Lubricant supply unit, bearing device, and mechanical device

Abstract

A lubricant supply unit (104) capable of extending bearing lubrication life comprises: a tank (125) in which lubricant (126) is accommodated; a pump (130); and a supply path member (140) which fluidically communicates with the pump (130). The pump (130) supplies the lubricant (126) from the tank (125) to the supply path member (140). The supply path member (140) is located at the lowermost part of the lubricant supply unit (104). The supply path member (140) includes: an inflow port (144) that is connected to the pump (130); a discharge port (145) that faces the interior of a bearing (102) to which the lubricant supply unit (104) is attached and that discharges the lubricant (126) to the interior of the bearing (102); and a discharge path (146) that is connected to the discharge port (145) and that extends upward.

Description

Lubricating oil supply unit, bearing device and mechanical device

[0001] The present disclosure relates to a lubricating oil supply unit, a bearing device, and a mechanical device.

[0002] Japanese Patent No. 6495700 (Patent Document 1) discloses a bearing device including a bearing and a lubricating oil supply unit connected to the bearing. The lubricating oil supply unit includes a holding part that holds lubricating oil, a supply part that supplies lubricating oil from the holding part to the inside of the bearing, and a power generation part that generates electricity.

[0003] Patent No. 6495700

[0004] However, the bearing device described in Patent Document 1 has room for extending the lubrication life of the bearing. The present disclosure has been made in consideration of the above-mentioned problems, and its purpose is to provide a lubricating oil supply unit, a bearing device, and a mechanical device that can extend the lubrication life of the bearing.

[0005] An object of the present invention is to provide a bearing device and a machine device that can smoothly supply lubricating oil to the rolling contact parts without increasing the size of the equipment.

[0006] An object of the present invention is to provide a bearing device and a mechanical device that can efficiently consume lubricating oil sealed in a tank while suppressing temperature rise in a high-speed rotation bearing without increasing the size of the equipment.

[0007] The lubricant supply unit of the present disclosure includes a tank that stores lubricant, a pump, and a supply path member that is fluidly connected to the pump. The pump supplies lubricant from the tank to the supply path member. The supply path member is disposed at the bottom of the lubricant supply unit. The supply path member includes an inlet connected to the pump, a discharge port that faces the interior of a bearing to which the lubricant supply unit is attached and discharges lubricant into the interior of the bearing, and a discharge path that is connected to the discharge port and extends upward.

[0008] The bearing device of the present disclosure includes the lubricant supply unit of the present disclosure and a bearing to which the lubricant supply unit is attached.

[0009] The machine device of the present disclosure includes a lubricant supply unit of the present disclosure, a bearing to which the lubricant supply unit is attached, a shaft, a motor that rotates the shaft, and a machine controller that controls the motor. After the controller stops operation of the pump, the machine controller operates the motor to rotate the shaft.

[0010] A bearing device according to one embodiment of the present disclosure includes a bearing and a lubricant supply unit that supplies lubricant to the bearing. The bearing includes a plurality of rolling elements and a cage. The plurality of rolling elements are arranged side by side on an annular raceway. The cage holds the plurality of rolling elements. The cage has a cage inner diameter surface formed on the inner diameter side in the radial direction. The lubricant supply unit includes a holding portion and a nozzle member. The holding portion holds lubricant to be supplied to the inside of the bearing. The nozzle member supplies lubricant from the holding portion to the inside of the bearing. The nozzle member has a tip surface. The tip surface is a flat surface that allows the lubricant to form oil droplets toward the cage inner diameter surface.

[0011] A mechanical device according to one embodiment of the present disclosure includes a rotating shaft, a housing, and the bearing device. The housing is disposed on the outer periphery of the rotating shaft. The bearing device rotatably supports the rotating shaft relative to the housing.

[0012] A bearing device according to one embodiment of the present disclosure includes a bearing and a lubricant supply unit that supplies lubricant to the bearing. The bearing includes an outer ring and an inner ring. The outer ring has an outer ring rolling surface on its inner circumferential surface. The inner ring has an inner ring rolling surface on its outer circumferential surface and is disposed inside the outer ring so that the inner ring rolling surface faces the outer ring rolling surface. The lubricant supply unit includes a holding portion, a Peltier element, a first heat conductor, a second heat conductor, and a power source. The holding portion holds the lubricant to be supplied to the interior of the bearing. The first heat conductor and the second heat conductor sandwich the Peltier element. The power source is capable of supplying power to the Peltier element. Driving the Peltier element by the power source enables heat to be transferred from the first heat conductor to the second heat conductor.

[0013] A mechanical device according to one embodiment of the present disclosure includes a rotating shaft, a housing, and the bearing device. The housing is disposed on the outer periphery of the rotating shaft. The bearing device rotatably supports the rotating shaft relative to the housing.

[0014] According to the lubricating oil supply unit, bearing device, and mechanical device of the present disclosure, the lubrication life of the bearing can be extended.

[0015] According to the above, it is possible to provide a bearing device and a mechanical device that can smoothly supply lubricating oil to the rolling contact portion without increasing the size of the equipment.

[0016] According to the above, it is possible to provide a bearing device and a mechanical device that can efficiently consume the lubricating oil sealed in the tank while suppressing a rise in the temperature of the bearing even when rotating at high speeds, without increasing the size of the equipment.

[0017] 1 is a schematic cross-sectional view of a bearing device according to a first embodiment. FIG. 2 is a schematic cross-sectional view of the bearing device according to the first embodiment, taken along the section line II-II shown in FIG. 1 . FIG. 3 is a schematic enlarged partial cross-sectional view of a region III shown in FIG. 1 of the bearing device according to the first embodiment. FIG. 4 is a circuit block diagram showing the configuration of an electric circuit of a main part of a lubricating oil supply unit according to the first embodiment. FIG. 5 is a schematic enlarged partial cross-sectional view of a power generation unit included in the lubricating oil supply unit according to the first embodiment. FIG. 6 is a schematic perspective view of a nozzle member included in the lubricating oil supply unit according to the first embodiment. FIG. 7 is a schematic cross-sectional view of a mechanical device according to the first embodiment. FIG. 8 is a circuit block diagram showing the configuration of an electric circuit of a main part of a mechanical device according to the first embodiment. FIG. 9 is a timing chart showing the operation of a pump, etc. FIG. 10 is a schematic enlarged partial cross-sectional view of the bearing device according to the first embodiment, showing how lubricating oil is supplied to the inside of a bearing. FIG. 11 is a schematic enlarged partial cross-sectional view of the bearing device according to the first embodiment, showing how lubricating oil is supplied to the inside of a bearing. 26 is a circuit block diagram showing the configuration of an electric circuit of a main part of a lubricating oil supply unit according to a modified example of the first embodiment. FIG. 27 is a circuit block diagram showing the configuration of an electric circuit of a main part of a mechanical device according to a modified example of the first embodiment. FIG. 28 is a schematic cross-sectional view of a bearing device according to a second embodiment. FIG. 29 is a schematic partially enlarged cross-sectional view of the bearing device according to the second embodiment, showing the region XIX shown in FIG. 18 . FIG. 29 is a schematic cross-sectional view of a lubricating oil supply unit according to a third embodiment. FIG. 30 is a schematic cross-sectional view of the lubricating oil supply unit according to the third embodiment, showing the lubricating oil supply unit according to the third embodiment when the lubricating oil in the tank has decreased. FIG. 31 is a schematic cross-sectional view of the lubricating oil supply unit according to the fourth embodiment. FIG. 32 is a schematic cross-sectional view of the lubricating oil supply unit according to the fourth embodiment, taken along the cross-sectional line XXIII-XXIII shown in FIG. 22 . FIG. 33 is a schematic cross-sectional view of the lubricating oil supply unit according to the fourth embodiment, taken along the cross-sectional line XXIV-XXIV shown in FIG. 22 . FIG. 34 is a schematic side view of a bearing device according to the fifth embodiment. FIG. 35 is a schematic cross-sectional view of a portion along the line A-A in FIG. 25 in a fifth embodiment. FIG. 36 is an enlarged schematic cross-sectional view of the region XXVII surrounded by a dotted line in FIG. 37. FIG. 38 is a schematic perspective view of a circular ring-shaped nozzle member according to the fifth embodiment.34 is an enlarged schematic perspective view of a first example of region B surrounded by a dotted line in FIG. 28 . 35 is a schematic perspective view of the region on the arrow side of line XXX-XXX in FIG. 29 , further enlarged from FIG. 29 . 36 is an enlarged schematic perspective view of a second example of region B surrounded by a dotted line in FIG. 28 . 37 is an enlarged schematic perspective view of a third example of region B surrounded by a dotted line in FIG. 28 . 38 is an enlarged schematic perspective view of a fourth example of region B surrounded by a dotted line in FIG. 28 . 39 is a schematic cross-sectional view of a portion along line A-A in FIG. 25 in embodiment 6. 39 is an enlarged schematic cross-sectional view of region XXXV surrounded by a dotted line in FIG. 34 . 39 is a schematic perspective view of a circular ring-shaped nozzle member in embodiment 6. 39 is an enlarged schematic perspective view of a first example of region C surrounded by a dotted line in FIG. 36 . 39 is a schematic perspective view of the region on the arrow side of line XXXVIII-XXXVIII in FIG. 37 , further enlarged from FIG. 37 . 49 is an enlarged schematic perspective view of a second example of an area C surrounded by a dotted line in FIG. 36. It is an enlarged schematic cross-sectional view showing a state in which there is a possibility of interference between the nozzle member and the inner diameter surface of the cage, as a comparative example to FIG. 35. It is a schematic cross-sectional view of a mechanical device to which the bearing device shown in FIG. 25 is applied. It is a schematic cross-sectional view of the mechanical device shown in FIG. 41. It is a schematic side view of a bearing device according to embodiment 8. It is a schematic cross-sectional view of a portion taken along line XLIV-XLIV in FIG. 43 in embodiment 8. It is a schematic cross-sectional view of a basic form of a portion taken along line A-A in FIG. 43. It is a schematic cross-sectional view of a first modified example of a portion taken along line A-A in FIG. 43. It is a schematic cross-sectional view of a second modified example of a portion taken along line A-A in FIG. 43. It is a schematic side view of a bearing device according to embodiment 9. It is a schematic perspective view showing the initial state of a first example of the lubricating oil tank shown in FIG. 48, which is illustrated in a simplified form compared to FIG. 48. It is a schematic cross-sectional view of a portion taken along line L-L in FIG. 49. 51. is a schematic perspective view showing a state in which the bimetal has been deformed relative to that of FIG. 49. is a schematic cross-sectional view of a portion taken along line LII-LII of FIG. 51. is a schematic perspective view showing an initial state of a second example of the lubricating oil tank shown in FIG. 48, which is illustrated in a simplified form compared to FIG. 48. is a schematic cross-sectional view of a portion taken along line LIV-LIV of FIG. 53. is a schematic perspective view showing a state in which the bimetal has been deformed relative to that of FIG. 53. is a schematic cross-sectional view of a portion taken along line LVI-LVI of FIG. 55. is a schematic side view of a bearing device according to embodiment 10. is a schematic perspective view showing the initial state of the lubricating oil tank in embodiment 10, similar to FIG. 49.68 is a schematic perspective view showing a state in which the bimetal has been deformed compared to FIG. 58. FIG. 69 is a schematic side view of a bearing device according to embodiment 11. FIG. 69 is a schematic side view of a bearing device according to embodiment 12. FIG. 70 is a graph showing a first example of the voltage of another power storage circuit over time. FIG. 71 is a graph showing a second example of the voltage of another power storage circuit over time. FIG. 72 is a graph showing a third example of the voltage of another power storage circuit over time. FIG. 73 is a graph showing a fourth example of the voltage of another power storage circuit over time. FIG. 74 is a schematic side view of a bearing device according to a first example of embodiment 13. FIG. 75 is a schematic side view of a bearing device according to a second example of embodiment 13. FIG. 76 is a schematic cross-sectional view of a mechanical device to which the bearing device shown in FIG. 43 is applied. FIG. 77 is a schematic cross-sectional view of the mechanical device shown in FIG.

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.

[0019] 1 to 6, a bearing device 101 according to a first embodiment will be described. The bearing device 101 includes a bearing 102, a spacer 103, and a lubricating oil supply unit 104.

[0020] Referring to Fig. 1, the bearing 102 is, for example, an angular contact ball bearing. The bearing 102 mainly includes an inner ring 110, an outer ring 114, a plurality of rolling elements 117, a cage 118, and a seal member 119. The bearing 102 includes an end face 102a and an end face 102b opposite the end face 102a. The end faces 102a and 102b are both end faces of the bearing 102 in the direction of the axis O (hereinafter referred to as the "axial direction"). Of the end faces 102a and 102b, the end face 102a is the end face of the bearing 102 on the side where the lubricating oil supply unit 104 or the spacer 103 is arranged. The end face 102a includes an end face 110a of the inner ring 110 and an end face 114a of the outer ring 114. The end face 102b includes an end face 110b of the inner ring 110 and an end face 114b of the outer ring 114. In this embodiment, the inner ring 110 is a rotating ring that rotates around the axis O of the bearing 102, and the outer ring 114 is a fixed ring. The axis O of the bearing 102 is the rotation axis of the rotating ring (e.g., the inner ring 110) of the bearing 102.

[0021] The inner ring 110 includes an end face 110a, an end face 110b opposite to the end face 110a, and an outer peripheral surface 111. The end faces 110a and 110b are both end faces of the inner ring 110 in the axial direction of the bearing 102. Of the end faces 110a and 110b, the end face 110a is the end face of the inner ring 110 on the side where the lubricating oil supply unit 104 or the spacer 103 is arranged. The outer peripheral surface 111 is connected to the end faces 110a and 110b.

[0022] The outer peripheral surface 111 includes an inner ring raceway surface 112 on which a plurality of rolling elements 117 roll, and an inclined portion 113. The inclined portion 113 is connected to the inner ring raceway surface 112. In the present embodiment, the inclined portion 113 is an inclined surface. The inclined portion 113 is inclined with respect to the axis O of the bearing 102 (the axis of the lubricant supply unit 104) so ​​as to approach the outer ring 114 as it moves from the end face 102a of the bearing 102 (the end face 110a of the inner ring 110) toward the inner ring raceway surface 112. The inclination angle θ of the inclined portion 113 with respect to the axial direction of the bearing 102 is, for example, 1° or more and 45° or less. Therefore, gravity acting on the lubricant 126 supplied to the inclined portion 113 can cause the lubricant 126 to flow along the inclined portion 113 toward the rolling elements 117. Furthermore, centrifugal force generated by the rotation of the rotating ring (e.g., inner ring 110) of the bearing 102 can promote the flow of the lubricating oil 126 toward the rolling elements 117. The lower limit of the inclination angle θ may be 2°. The upper limit of the inclination angle θ may be 40° or 30°.

[0023] The outer ring 114 includes an end face 114a, an end face 114b opposite to the end face 114a, and an inner circumferential surface 115. The end faces 114a, 114b are both end faces of the outer ring 114 in the axial direction of the bearing 102. Of the end faces 114a, 114b, the end face 114a is the end face of the outer ring 114 on which the lubricant supply unit 104 or the spacer 103 is arranged. The inner circumferential surface 115 is connected to the end faces 114a and 114b. The inner circumferential surface 115 includes an outer ring raceway surface 116 on which a plurality of rolling elements 117 roll. The outer ring raceway surface 116 faces the inner ring raceway surface 112 in the radial direction of the bearing 102. Grease (not shown) is sealed in the bearing space between the inner ring 110 and the outer ring 114.

[0024] A plurality of rolling elements 117 are interposed between inner ring 110 and outer ring 114. The plurality of rolling elements 117 roll on inner ring raceway surface 112 and outer ring raceway surface 116. The plurality of rolling elements 117 are in contact with inner ring raceway surface 112 and outer ring raceway surface 116 via at least one of grease and lubricating oil 126.

[0025] The cage 118 holds the plurality of rolling elements 117 at regular intervals. The seal member 119 is disposed on the end face 102b of the bearing 102. The seal member 119 seals in the grease or lubricating oil 126.

[0026] 1 , the spacer 103 abuts against the end face 102a of the end faces 102a and 102b of the bearing 102. Specifically, the spacer 103 includes an inner ring spacer 121 and an outer ring spacer 122. The inner ring spacer 121 abuts against the end face 110a of the inner ring 110. The outer ring spacer 122 abuts against the end face 114a of the outer ring 114.

[0027] 1 to 6 , the lubricant supply unit 104 is attached to the bearing 102. For example, the lubricant supply unit 104 is attached to the bearing 102 via a spacer 103. The lubricant supply unit 104 is disposed between an inner ring spacer 121 and an outer ring spacer 122. The lubricant supply unit 104 has a ring shape centered on the axis O of the bearing 102 (the axis of the lubricant supply unit 104). The lubricant supply unit 104 mainly includes a tank 125, a tube 128, a pump 130, a supply path member 140, a power supply unit 132, a voltage sensor 135, a controller 136, and a housing 137.

[0028] The tank 125 contains the same type of lubricating oil 126 as the base oil of the grease sealed in the bearing 102. The tank 125 is formed, for example, from a material having a thermal conductivity of 0.10 W / (m·K) or more. The tank 125 is formed from a material that is resistant to the lubricating oil 126. The tank 125 is preferably formed from a material that can withstand a heat temperature of 80°C or more. The tank 125 is formed from a resin material such as polycarbonate, polyethylene, polyamide, polyether ether ketone (PEEK), polypropylene, or polyethylene terephthalate (PET). The tank 125 may be arranged in an arc shape along the annular housing body 138. The tank 125 may also be formed from a transparent resin so that the interior of the tank 125 can be seen from the outside of the tank 125.

[0029] The tank 125 may be detachable from the pump 130 and the housing 137. Therefore, when the lubricating oil 126 in the tank 125 in use runs out, the used tank 125 can be removed and replaced with a spare tank 125 (a tank 125 filled with the lubricating oil 126), thereby allowing the lubricating oil 126 to be replenished in a short time.

[0030] The tube 128 is connected to the tank 125 and the pump 130. The tube 128 may be integrally formed with the tank 125. The tube 128 may be detachable from the pump 130. Therefore, when the lubricating oil 126 in the tank 125 runs out, the tube 128 can be detached from the pump 130 and the lubricating oil 126 can be replenished into the tank 125 from the tube 128.

[0031] The pump 130 supplies the lubricating oil 126 from the tank 125 to the supply path member 140. Specifically, when the pump 130 is operating, the pump 130 sucks the lubricating oil 126 in the tank 125 through the tube 128 and sends the lubricating oil 126 to the supply path member 140. The pump 130 is, for example, a micropump.

[0032] 2 , 4 and 5 , the power supply unit 132 generates electric power and supplies the electric power to the controller 136. The power supply unit 132 is connected to the controller 136. Specifically, the power supply unit 132 includes a power generation unit 133 and a charging unit 134. The power generation unit 133 is connected to the charging unit 134. The charging unit 134 is connected to the controller 136.

[0033] The power generating unit 133 may be one that generates electricity by, for example, the Seebeck effect. Specifically, as shown in FIG. 5 , the power generating unit 133 includes a thermal conductor 133a, a thermal conductor 133b, and a thermoelectric element 133c. The thermal conductor 133a penetrates the outer peripheral surface of the housing 137 and is connected to the outer ring spacer 122. The thermal conductor 133b penetrates the outer peripheral surface of the housing 137 and is disposed opposite the inner ring spacer 121. The thermal conductor 133b is spaced apart from the inner ring spacer 121. The thermal conductors 133a and 133b are formed of a material with high thermal conductivity, such as a metal or a metal alloy. The thermal conductors 133a and 133b are formed of, for example, silver (Ag), copper (Cu), gold (Au), a copper alloy containing copper as a main component, or a sintered alloy containing copper as a main component. The thermoelectric element 133c is disposed between the thermal conductors 133a and 133b and is fixed in close contact with the thermal conductors 133a and 133b. The thermoelectric element 133c is, for example, an element that utilizes the Seebeck effect of a Peltier element. A thermally conductive adhesive or thermal grease may be provided between the inner peripheral surface of the outer ring spacer 122 and the thermal conductor 133a, between the thermal conductor 133a and the thermoelectric element 133c, and between the thermoelectric element 133c and the thermal conductor 133b.

[0034] The temperatures of the inner ring 110 and the outer ring 114 rise due to frictional heat between the inner ring 110 and the rolling elements 117 and frictional heat between the outer ring 114 and the rolling elements 117. Because the outer ring 114 is typically incorporated into a housing of an apparatus (e.g., the inner housing 152 of the mechanical device 150 in FIG. 7 ), heat from the outer ring 114 dissipates into the housing. Therefore, the temperature of the outer ring 114 is lower than that of the inner ring 110, creating a temperature difference between the inner ring 110 and the outer ring 114. The temperature of the outer ring 114 is transferred to the outer ring spacer 122, and the temperature of the inner ring 110 is transferred to the inner ring spacer 121. A temperature difference occurs between both end surfaces of the thermoelectric element 133c, which is disposed between the thermal conductors 133a and 133b. Therefore, the thermoelectric element 133c generates electricity through the Seebeck effect. By using the power generation unit 133, it is not necessary to supply power to the lubricant supply unit 104 from outside the lubricant supply unit 104. An electric wire for supplying power to the controller 136 from outside the lubricant supply unit 104 can be omitted.

[0035] The power generated by the power generation unit 133 is charged into the charging unit 134. Specifically, the charging unit 134 includes a capacitor (not shown) such as an electric double layer capacitor. The power generated by the power generation unit 133 is charged into the capacitor. The voltage sensor 135 detects the voltage of the charging unit 134. The voltage sensor 135 can detect the amount of charge in the charging unit 134.

[0036] The controller 136 is, for example, a microcomputer including a processor, a random access memory (RAM), and a storage device such as a read-only memory (ROM). The processor may be, for example, a central processing unit (CPU). The RAM functions as a working memory that temporarily stores data processed by the processor. The storage device stores, for example, programs to be executed by the processor. In this embodiment, the controller 136 controls the operation of the pump 130 by having the processor execute the programs stored in the storage device. Therefore, the timing of supplying the lubricating oil 126 to the bearing 102 (for example, the start time of supplying the lubricating oil 126 and the supply interval of the lubricating oil 126) and the amount of the lubricating oil 126 supplied to the bearing 102 can be appropriately set.

[0037] For example, when the rotation of the shaft 151 (see FIG. 7 ) rotatably supported by the bearing 102 is stopped, or when the bearing 102 is being used with a dn value of 200,000 or less, the controller 136 operates the pump 130 to supply the lubricating oil 126 from the tank 125 to the supply path member 140. The dn value of the bearing 102 is given by the product of the inner diameter d of the inner ring 110 of the bearing 102, expressed in mm, and the rotation speed of the inner ring 110 of the bearing 102, expressed in rpm. The controller 136 controls the operation of the pump 130 so that droplets 126d (see FIG. 11 ) of the lubricating oil 126 formed at the discharge port 145 adhere to the inside of the bearing 102.

[0038] 1, 2, and 5, the housing 137 has an annular shape centered on the axis O of the bearing 102 (the axis of the lubricant supply unit 104). The housing 137 accommodates the tank 125, the tube 128, the pump 130, the tube 141, the power supply unit 132, and the controller 136. The tank 125, the tube 128, the pump 130, the power supply unit 132, and the controller 136 are arranged in the circumferential direction of the bearing 102 (the circumferential direction of the lubricant supply unit 104) centered on the axis O of the bearing 102 (the axis of the lubricant supply unit 104). The housing 137 is formed of a resin such as a thermoplastic resin (such as polyphenylene sulfide (PPS)). Alternatively, the housing 137 may be formed of a transparent resin so that the interior of the housing 137 can be seen from the outside of the housing 137.

[0039] The housing 137 includes a housing body 138 and a lid 139. The housing body 138 and the lid 139 may be formed of the same material or different materials. At least two of the tank 125, the housing body 138, and the lid 139 may be integrally formed.

[0040] As shown in FIG. 1 , the housing body 138 has a cup shape with an open surface on the side opposite the bearing 102. An opening is provided on the side of the housing body 138 opposite the bearing 102. The outer peripheral surface of the housing body 138 may be fixed to the inner peripheral surface of the outer ring spacer 122. The outer peripheral surface of the housing body 138 may be bonded to the inner peripheral surface of the outer ring spacer 122 with an adhesive such as an epoxy adhesive. The housing body 138 may be fixed to a fixed ring (e.g., the outer ring 114) of the bearing 102. The housing body 138 is spaced from the inner ring spacer 121.

[0041] The lid 139 closes the opening of the housing body 138. The lid 139 may be detachable from the housing body 138. The lid 139 may be fixed to the housing body 138 using a detachable fixing member (not shown) such as a screw. The lid 139 can be removed from the housing body 138 by removing the fixing member. Therefore, the tank 125 housed in the housing body 138 can be replenished with the lubricating oil 126 without removing the entire lubricating oil supply unit 104 from the bearing device 101. A faulty controller 136 can be replaced with a new controller 136, and a faulty power supply unit 132 can be replaced with a new power supply unit 132, without removing the entire lubricating oil supply unit 104 from the bearing device 101.

[0042] 1 and 2 , in a vertically installed state in which the axis O of the bearing 102 is positioned horizontally, the supply path member 140 is disposed at the lowest part of the lubricant supply unit 104. In this specification, the supply path member 140 being disposed at the lowest part of the lubricant supply unit 104 means that when the bearing device 101 is incorporated into equipment (for example, the mechanical device 150 in FIG. 7 ), the supply path member 140 is disposed at the lowest part of the lubricant supply unit 104 in the vertical direction. The supply path member 140 is fluidly connected to the pump 130.

[0043] The supply path member 140 includes an inlet 144, an outlet 145, and a discharge path 146. The inlet 144 is a first end of the supply path member 140 and is connected to the pump 130. The outlet 145 is a second end of the supply path member 140 opposite the inlet 144 and faces the interior (e.g., the inclined portion 113) of the bearing 102 to which the lubricating oil supply unit 104 is attached. The lubricating oil 126 is discharged from the outlet 145 to the interior of the bearing 102. The discharge path 146 is connected to the outlet 145 and extends upward. In this specification, the term "upwardly extending discharge path 146" means that when the bearing device 101 is incorporated into equipment (e.g., the mechanical device 150 in FIG. 7), the discharge port 145 is positioned vertically above the inlet 147 of the discharge path 146. The supply path member 140 includes a tube 141 and a nozzle member 142 .

[0044] The tube 141 is connected to the pump 130 and the nozzle member 142. One end of the tube 141 is connected to the pump 130 and is an inlet 144 of the supply path member 140. The other end of the tube 141 is connected to an inlet 147 of the discharge path 146. The tube 141 is in fluid communication with the discharge path 146.

[0045] As shown in FIGS. 1 and 6 , the nozzle member 142 has an annular shape centered on the axis O of the bearing 102 (the axis of the lubricating oil supply unit 104). A discharge passage 146 is provided in the nozzle member 142. A discharge port 145 is provided on the inner peripheral surface of the nozzle member 142. The nozzle member 142 is fixed to the housing 137. For example, the nozzle member 142 is detachably fixed to the surface of the housing main body 138 facing the bearing 102 using a fixing member (not shown) such as a screw. An inlet 147 of the discharge passage 146 is provided on the surface of the nozzle member 142 connected to the housing main body 138. A sealing groove surrounding the inlet 147 of the discharge passage 146 is provided on the surface of the nozzle member 142 connected to the housing main body 138. A sealing member 148 such as an O-ring is disposed in the sealing groove. The seal member 148 prevents the lubricating oil 126 supplied from the tube 141 to the discharge passage 146 from leaking from the connection between the nozzle member 142 and the housing main body 138 .

[0046] The nozzle member 142 includes a surface portion 142a that faces the interior of the bearing 102. The discharge port 145 of the supply path member 140 is an opening formed in the surface portion 142a, and faces the interior of the bearing 102. The interior of the bearing 102 that the discharge port 145 of the supply path member 140 faces and to which the lubricating oil 126 is supplied is, for example, the inclined portion 113 of the inner ring 110. The surface portion 142a of the nozzle member 142 that faces the interior of the bearing 102 may extend from the end face 110a of the inner ring 110 to a position adjacent to the inner ring raceway surface 112 (for example, a position closer to the inner ring raceway surface 112 than the end of the cage 118 in the axial direction of the bearing 102).

[0047] The inner diameter of the discharge passage 146 can be appropriately set based on the surface tension of the lubricating oil 126 due to the viscosity of the lubricating oil 126 and the discharge amount of the lubricating oil 126. The distance D between the discharge port 145 of the supply passage member 140 and the interior of the bearing 102 (e.g., the inclined portion 113 of the inner ring 110) to which the lubricating oil 126 is supplied is set to satisfy the following two conditions. The first condition is that droplets 126d of the lubricating oil 126 generated at the discharge port 145 (see FIG. 11 ) can adhere to the interior of the bearing 102. The second condition is that the lubricating oil 126 can easily flow toward the rolling elements 117 through the gap between the surface portion 142a of the nozzle member 142 and the inclined portion 113 of the inner ring 110 due to capillary action. The distance D can be, for example, 0.1 mm or more and 3.0 mm or less. The lower limit of the distance D may be 0.2 mm. The upper limit of the distance D may be 2.5 mm or 2.0 mm. In this specification, distance D is defined as the distance between the center of the discharge port 145 and the intersection of a line extending the centerline of the discharge passage 146 at the discharge port 145 with the interior of the bearing 102 (e.g., the inclined portion 113).

[0048] 7 and 8 , a mechanical device 150 according to this embodiment, which is one application example of the bearing device 101, will be described. The mechanical device 150 is, for example, a machine tool. The mechanical device 150 mainly includes a shaft 151, an inner housing 152, an outer housing 153, a spacer 154, the bearing device 101, a motor 157, a rotation sensor 158, and a machine controller 159.

[0049] The shaft 151 is, for example, the main shaft of a machine tool. A tool or the like is attached to the shaft 151. The inner housing 152 is disposed around the shaft 151. The outer housing 153 is disposed outside the inner housing 152. The bearing device 101 supports the shaft 151 rotatably relative to the inner housing 152. Two bearing devices 101 are disposed around the shaft 151. The inner ring 110 of the bearing 102 is fitted and fixed to the side surface of the shaft 151. The inner ring spacer 121 is fitted and fixed to the side surface of the shaft 151. The inner ring spacer 121 is disposed between the inner ring 110 and the inner ring spacer 155, and abuts against the inner ring 110 and the inner ring spacer 155. The outer ring 114 of the bearing 102 is fitted and fixed to the inner peripheral surface of the inner housing 152. The outer ring spacer 122 is fitted and fixed to the inner peripheral surface of the inner housing 152. The outer ring spacer 122 is disposed between the outer ring 114 and the outer ring spacer 156, and abuts against the outer ring 114 and the outer ring spacer 156.

[0050] The spacer 154 is disposed between the two spacers 103 and abuts against the two spacers 103. The spacer 154 includes an inner ring spacer 155 and an outer ring spacer 156. The inner ring spacer 155 is fitted and fixed to the side surface of the shaft 151 and abuts against the inner ring spacer 121. The outer ring spacer 156 is fitted and fixed to the inner peripheral surface of the inner housing 152 and abuts against the outer ring spacer 122. The spacers 103 and 154 position the bearing 102 in the axial direction of the bearing 102.

[0051] The motor 157 rotates the shaft 151. When the shaft 151 rotates, a tool (not shown) or the like attached to the shaft 151 rotates. The rotation sensor 158 detects the number of rotations of the shaft 151.

[0052] The machine controller 159 is, for example, a microcomputer including a processor, a RAM, and a storage device such as a ROM. For example, a CPU may be used as the processor. The RAM functions as a working memory that temporarily stores data to be processed by the processor. The storage device stores, for example, programs to be executed by the processor. In this embodiment, the machine controller 159 controls the operation of the machine device 150 by having the processor execute the programs stored in the storage device. For example, the machine controller 159 controls the motor 157. For example, after the controller 136 stops the operation of the pump 130, the machine controller 159 operates the motor 157 to rotate the shaft 151.

[0053] The operation of the lubricating oil supply unit 104 will be described with reference to Figure 9. While the rotation of the shaft 151 is stopped (i.e., while the rotation speed of the shaft 151 is zero), the controller 136 operates the pump 130 to supply the lubricating oil 126 to the inside of the bearing 102 (e.g., the inclined portion 113). Specifically, the pump 130 sucks the lubricating oil 126 from the tank 125 and sends it to the supply path member 140. The lubricating oil 126 is supplied from the tank 125 through the supply path member 140 and from the discharge port 145 to the inside of the bearing 102 (e.g., the inclined portion 113).

[0054] More specifically, as shown in FIGS. 10 to 12 , the controller 136 controls the operation of the pump 130 so that droplets 126d of the lubricant 126 formed at the discharge port 145 adhere to the inside of the bearing 102. When the pump 130 operates, the lubricant 126 is supplied to the discharge path 146, as shown in FIG. 10 . As the pump 130 continues to operate, droplets 126d of the lubricant 126 are formed at the discharge port 145. The droplets 126d of the lubricant 126 gradually grow larger, and as shown in FIG. 11 , the droplets 126d of the lubricant 126 come into contact with the inside of the bearing 102 (e.g., the inclined portion 113). When the controller 136 stops the pump 130, the supply of the lubricant 126 from the discharge port 145 stops. As shown in FIG. 12 , the lubricant 126 that has come into contact with the inside of the bearing 102 remains inside the bearing 102 (e.g., the inclined portion 113). In this way, the lubricating oil 126 is supplied to the interior (e.g., inclined portion 113) of the bearing 102. When the interior of the bearing 102 to which the lubricating oil 126 is supplied is the inclined portion 113, gravity acting on the lubricating oil 126 causes the lubricating oil 126 to flow on the inclined portion 113 toward the rolling elements 117. Furthermore, capillary action acting on the gap between the surface portion 142a of the nozzle member 142 and the interior of the bearing 102 (e.g., inclined portion 113) causes the lubricating oil 126 to flow on the inclined portion 113 toward the rolling elements 117.

[0055] 9, machine controller 159 controls motor 157 to rotate shaft 151. For example, controller 136 sends a signal to machine controller 159 indicating that pump 130 has changed from an operating state (on state) to a stopped state (off state). After receiving the signal, machine controller 159 operates motor 157 to rotate shaft 151.

[0056] When the shaft 151 rotates, the rotating ring (e.g., the inner ring 110) of the bearing 102 fixed to the shaft 151 also rotates. The centrifugal force caused by the rotation of the inner ring 110 promotes the flow of lubricating oil 126 toward the inner ring rolling surface 112. The lubricating oil 126 is supplied between the inner ring rolling surface 112 and the rolling elements 117. As the rolling elements 117 roll on the inner ring rolling surface 112 and the outer ring rolling surface 116, the lubricating oil 126 is also supplied between the rolling elements 117 and the outer ring 114. In this way, the lubricating oil 126 can contribute to lubrication between the rolling elements 117 and the inner ring 110 and between the rolling elements 117 and the outer ring 114.

[0057] Thus, in this embodiment, while the rotation of the shaft 151 is stopped, the controller 136 operates the pump 130 to supply the lubricating oil 126 to the inside (for example, the inclined portion 113) of the bearing 102. Then, while the shaft 151 is rotating, the controller 136 stops the pump 130 to stop the supply of the lubricating oil 126 to the inside of the bearing 102.

[0058] As shown in FIG. 9 , the power generated by the power generation unit 133 is charged into the charging unit 134, and the voltage of the charging unit 134 reaches the target voltage V required to operate the pump 130. ｔ When the supply interval time ΔT ｉ It is desirable to operate the pump 130 every time the time elapses.

[0059] For example, the target voltage V required to operate the pump 130 ｔ If the charging time until the voltage of the charging unit 134 reaches the target voltage V is earlier than the timing of supplying the lubricating oil 126, the voltage of the charging unit 134 will ｔ After a predetermined time has elapsed since the voltage of the charging unit 134 reaches the target voltage V, the pump 130 is driven by the power stored in the charging unit 134. ｔ The supply interval time ΔT of the lubricating oil 126 is ｉSince the lubricating oil 126 can be supplied to the bearing 102 for a longer period of time, the lubrication life of the bearing 102 can be extended.

[0060] (Modifications) As shown in Fig. 13, the nozzle member 142 may have the shape of an arc that is part of an annulus centered on the axis O of the bearing 102 (the axis of the lubricant oil supply unit 104). As shown in Fig. 14, the circumferential end of the nozzle member 142 may have a tapered or streamlined shape. As shown in Fig. 15, the discharge port 145 may be provided in a flat surface of the nozzle member 142.

[0061] 16 and 17 , the lubricant supply unit 104, rather than the mechanical device 150, may include a rotation sensor 158 that detects the rotation speed of the shaft 151. The rotation sensor 158 is connected to the controller 136. The controller 136 controls the operation of the pump 130 based on the rotation speed of the shaft 151 output from the rotation sensor 158. For example, as shown in FIG. 9 , while the rotation of the shaft 151 is stopped (i.e., while the rotation speed of the shaft 151 is zero), the controller 136 operates the pump 130 to supply the lubricant 126 to the interior (e.g., the inclined portion 113) of the bearing 102. While the shaft 151 is rotating, the controller 136 stops the pump 130 to stop the supply of the lubricant 126 to the interior (e.g., the inclined portion 113) of the bearing 102.

[0062] The controller 136 may operate the pump 130 while the bearing 102 is in use at a dn value of 200,000 or less, and may stop the pump 130 while the bearing 102 is in use at a dn value greater than 200,000.

[0063] In this embodiment, the bearing 102 is an inner-ring rotating type bearing (a bearing in which the inner ring 110 is a rotating ring and the outer ring 114 is a fixed ring), but it may also be an outer-ring rotating type bearing (a bearing in which the outer ring 114 is a rotating ring and the inner ring 110 is a fixed ring). In this embodiment, the axial direction of the bearing 102 extends laterally (horizontally), but the axial direction of the bearing 102 may also extend vertically (vertically). The bearing 102 may be, for example, a deep groove ball bearing, a cylindrical roller bearing, a tapered roller bearing, or a self-aligning roller bearing. Capillary action acting in the gap between the surface portion 142a of the nozzle member 142 and the inclined portion 113 of the inner ring 110 does not have to be used to flow the lubricating oil 126 toward the rolling elements 117.

[0064] The effects of the lubricating oil supply unit 104, the bearing device 101, and the mechanical device 150 of this embodiment will be described.

[0065] The lubricating oil supply unit 104 of this embodiment includes a tank 125 that stores lubricating oil 126, a pump 130, and a supply path member 140 that is fluidly connected to the pump 130. The pump 130 supplies the lubricating oil 126 from the tank 125 to the supply path member 140. The supply path member 140 is disposed at the bottom of the lubricating oil supply unit 104. The supply path member 140 includes an inlet 144 connected to the pump 130, a discharge port 145 that faces the interior of the bearing 102 to which the lubricating oil supply unit 104 is attached and discharges the lubricating oil 126 into the interior of the bearing 102, and a discharge path 146 that is connected to the discharge port 145 and extends upward.

[0066] Because the supply path member 140 is disposed at the bottom of the lubricating oil supply unit 104, the lubricating oil 126 can move toward the pump 130 under its own weight. The amount of lubricating oil 126 remaining in the tank 125 that has not been used up decreases or disappears. More of the lubricating oil 126 in the tank 125 can be used up. According to the lubricating oil supply unit 104 of this embodiment, the lubrication life of the bearings 102 can be extended. Furthermore, because the amount of lubricating oil 126 remaining in the tank 125 that has not been used up decreases or disappears, the tank 125 can be made smaller. The lubricating oil supply unit 104 can be made smaller.

[0067] In the lubricant oil supply unit 104 of this embodiment, the tank 125 is formed of a material having a thermal conductivity of 0.10 W / (m·K) or more.

[0068] Therefore, the heat generated in the bearing 102 to which the lubricating oil supply unit 104 is attached warms the lubricating oil 126 in the tank 125. The fluidity of the lubricating oil 126 in the tank 125 improves, and the amount of lubricating oil 126 remaining in the tank 125 that cannot be used up is reduced or eliminated. More of the lubricating oil 126 in the tank 125 can be used up. The lubricating oil supply unit 104 of this embodiment can extend the lubrication life of the bearing 102.

[0069] In the lubricant oil supply unit 104 of this embodiment, the material forming the tank 125 is resin.

[0070] If the tank 125 is made of metal, metal burrs and metal powder may be generated inside the tank 125. Metal burrs and metal powder are hard. Therefore, if metal burrs and metal powder are supplied to the inside of the bearing 102 together with the lubricating oil 126, the bearing 102 will be damaged. In contrast, if the tank 125 is made of resin, metal burrs and metal powder will not be generated inside the tank 125. Even if resin burrs and resin powder are generated inside the tank 125, the resin burrs and resin powder are softer than metal burrs and metal powder. Therefore, even if resin burrs and resin are supplied to the inside of the bearing 102 together with the lubricating oil 126, damage to the bearing 102 can be prevented. The life of the bearing 102 can be extended.

[0071] Furthermore, since resin generally has a lower thermal conductivity than metal, the heat generated in the bearing 102 to which the lubricating oil supply unit 104 is attached warms the lubricating oil 126 in the tank 125 for a longer period of time. The fluidity of the lubricating oil 126 in the tank 125 is improved for a longer period of time, and the amount of lubricating oil 126 remaining in the tank 125 without being used up is reduced or eliminated. More of the lubricating oil 126 in the tank 125 can be used up. The lubricating oil supply unit 104 of this embodiment can extend the lubrication life of the bearing 102.

[0072] A plastic tank 125 is easier to mold and machine than a metal tank, which reduces the cost of the bearing 102.

[0073] In the lubricant oil supply unit 104 of this embodiment, the resin material forming the tank 125 is polycarbonate resin.

[0074] Polycarbonate resin has high resistance to the lubricating oil 126 and is heat resistant, so the lubricating oil 126 can be stored in the tank 125 for a long period of time, thereby extending the lubrication life of the bearing 102.

[0075] In the lubricant supply unit 104 of this embodiment, the supply path member 140 includes a nozzle member 142. The nozzle member 142 includes a discharge port 145 and a discharge path 146.

[0076] Because the supply path member 140 is disposed at the bottom of the lubricating oil supply unit 104, the lubricating oil 126 can move toward the pump 130 under its own weight. The lubricating oil 126 remaining in the tank 125 without being used up decreases or disappears. More of the lubricating oil 126 in the tank 125 can be used up. The lubricating oil supply unit 104 of this embodiment can extend the lubrication life of the bearings 102.

[0077] In the lubricant oil supply unit 104 of this embodiment, the nozzle member 142 has an arc shape that is part of a ring centered on the axis O of the bearing 102 .

[0078] Therefore, when churning occurs in the grease inside the bearing 102, the grease can escape from the gap between the inner ring 110 and the outer ring 114 where the nozzle member 142 is not disposed. This can mitigate the agitation heat of the grease that occurs when churning occurs and the re-entrapment of the grease. This can extend the lubrication life of the bearing 102.

[0079] In the lubricating oil supply unit 104 of this embodiment, the end of the nozzle member 142 in the circumferential direction of the bearing 102 has a tapered or streamlined shape.

[0080] This reduces the resistance of the air and grease flowing in the circumferential direction of the bearing 102. This extends the lubrication life of the bearing 102.

[0081] In the lubricant oil supply unit 104 of this embodiment, the discharge port 145 is provided on the flat surface of the nozzle member 142 .

[0082] Therefore, droplets 126d (see FIG. 11) of the lubricating oil 126 can be more stably formed at the discharge port 145. The lubricating oil 126 can be stably supplied to the bearing 102. The lubrication life of the bearing 102 can be extended.

[0083] The lubricant supply unit 104 of this embodiment further includes a controller 136 that controls the operation of the pump 130 .

[0084] The controller 136 can appropriately set the timing and amount of lubricating oil 126 supplied from the pump 130. This can extend the lubrication life of the bearings 102.

[0085] In the lubricant supply unit 104 of this embodiment, the controller 136 controls the operation of the pump 130 so that the droplets 126 d of the lubricant 126 formed at the discharge port 145 adhere to the inside of the bearing 102 .

[0086] Therefore, compared to when the lubricating oil 126 is injected into the inside of the bearing 102, the amount of lubricating oil 126 supplied each time can be reduced and the number of times the lubricating oil 126 is supplied can be increased. This can extend the lubrication life of the bearing 102. Furthermore, since the amount of lubricating oil 126 supplied each time can be reduced, the pump 130 can be made smaller. The lubricating oil supply unit 104 can be made smaller.

[0087] In the lubricating oil supply unit 104 of this embodiment, when the rotation of the shaft 151 rotatably supported by the bearing 102 is stopped, or when the bearing 102 is being used with a dn value of 200,000 or less, the controller 136 operates the pump 130 to supply the lubricating oil 126 from the tank 125 to the inside of the bearing 102.

[0088] Therefore, when the rotating ring of the bearing 102 (e.g., the inner ring 110) rotates together with the shaft 151, the swirling air flow (air curtain) generated by the rotation of the rotating ring of the bearing 102 may hinder the smooth supply of the lubricating oil 126 into the interior of the bearing 102. In contrast, in this embodiment, when the rotation of the shaft 151 is stopped or when the bearing 102 is being used with a dn value of 200,000 or less, the lubricating oil 126 is supplied from the tank 125 to the interior of the bearing 102. Therefore, while the lubricating oil 126 is being supplied to the interior of the bearing 102, the swirling air flow (air curtain) generated by the rotation of the rotating ring of the bearing 102 is absent or weak. This allows the lubricating oil 126 to be smoothly supplied into the interior of the bearing 102. This extends the lubrication life of the bearing 102.

[0089] The lubricant oil supply unit 104 of this embodiment further includes a rotation sensor 158 that detects the rotation of the shaft 151. The controller 136 controls the operation of the pump 130 based on the output from the rotation sensor 158.

[0090] Therefore, it is possible to appropriately set the timing of supplying the lubricating oil 126 in relation to the rotation state of the shaft 151. As a result, it is possible to extend the lubrication life of the bearing 102.

[0091] The bearing device 101 of this embodiment includes the lubricating oil supply unit 104 of this embodiment and a bearing 102 to which the lubricating oil supply unit 104 is attached.

[0092] This makes it possible to extend the lubrication life of bearing 102 included in bearing device 101. In bearing device 101 of the present embodiment, bearing 102 includes outer ring 114 including outer ring raceway surface 116 on its inner circumferential surface 115, inner ring 110 including inner ring raceway surface 112 on its outer circumferential surface 111 and arranged inside outer ring 114 so that inner ring raceway surface 112 faces outer ring raceway surface 116, and a plurality of rolling elements 117 that roll on outer ring raceway surface 116 and inner ring raceway surface 112. Outer circumferential surface 111 of inner ring 110 extends from an end face of inner ring 110 in the axial direction of bearing 102 to inner ring raceway surface 112, and includes an inclined portion 113 that approaches outer ring 114 as it moves from the end face of inner ring 110 toward inner ring raceway surface 112. The inside of the bearing 102 that faces the discharge port 145 of the supply passage member 140 of the lubricant supply unit 104 is an inclined portion 113 .

[0093] Therefore, gravity acting on the lubricating oil 126 can cause the lubricating oil 126 to flow up the inclined portion 113 toward the rolling elements 117. Furthermore, centrifugal force caused by the rotation of the rotating ring (e.g., the inner ring 110) of the bearing 102 can promote the flow of the lubricating oil 126 toward the rolling elements 117. The lubricating oil 126 can contribute to lubrication between the rolling elements 117 and the inner ring 110 and between the rolling elements 117 and the outer ring 114. The lubrication life of the bearing 102 can be extended.

[0094] In the bearing device 101 of this embodiment, the inclination angle θ of the inclined portion 113 with respect to the axial direction of the bearing 102 is equal to or greater than 1° and equal to or less than 45°.

[0095] Therefore, gravity acting on the lubricating oil 126 can cause the lubricating oil 126 to flow up the inclined portion 113 toward the rolling elements 117. Furthermore, centrifugal force caused by the rotation of the rotating ring (e.g., the inner ring 110) of the bearing 102 can promote the flow of the lubricating oil 126 toward the rolling elements 117. The lubricating oil 126 can contribute to lubrication between the rolling elements 117 and the inner ring 110 and between the rolling elements 117 and the outer ring 114. The lubrication life of the bearing 102 can be extended.

[0096] The machine device 150 of this embodiment includes the lubricant supply unit 104 of this embodiment, the bearing 102 to which the lubricant supply unit 104 is attached, a shaft 151 rotatably supported by the bearing 102, a motor 157 that rotates the shaft 151, and a machine controller 159 that controls the motor 157. While the controller 136 stops the operation of the pump 130, the machine controller 159 operates the motor 157 to rotate the shaft 151.

[0097] This prevents the smooth supply of lubricating oil 126 into the inside of bearing 102 from being hindered by the swirling air flow (air curtain) generated by the rotation of the rotating ring (e.g., inner ring 110) of bearing 102. Also, the centrifugal force caused by the rotation of the rotating ring (e.g., inner ring 110) of bearing 102 can promote the flow of lubricating oil 126 toward rolling elements 117. This can extend the lubrication life of bearing 102. This can allow mechanical device 150 to operate stably for a long period of time.

[0098] 18 and 19, a bearing device 101 according to a second embodiment will be described. The bearing device 101 according to the present embodiment has a similar configuration to the bearing device 101 according to the first embodiment, but differs mainly in the following respects.

[0099] In the present embodiment, a recess 113r is provided in inclined portion 113. Recess 113r is a circumferential groove extending in the circumferential direction of bearing 102. Recess 113r is arranged at a position facing discharge port 145 of supply path member 140. Recess 113r may be arranged at a position adjacent to inner ring raceway surface 112 (for example, at a position closer to inner ring raceway surface 112 than the end of cage 118 in the axial direction of bearing 102).

[0100] The lubricating oil 126 supplied to the interior of the bearing 102 through the discharge passage 146 is temporarily stored in the recess 113r. Gravity acting on the lubricating oil 126 causes the lubricating oil 126 stored in the recess 113r to flow up the inclined portion 113 toward the rolling elements 117. Furthermore, capillary action acting in the gap between the surface portion 142a of the nozzle member 142 and the interior of the bearing 102 (e.g., the inclined portion 113) causes the lubricating oil 126 stored in the recess 113r to flow up the inclined portion 113 toward the rolling elements 117. Then, the rotating ring (e.g., the inner ring 110) of the bearing 102 rotates together with the shaft 151. The centrifugal force caused by the rotation of the inner ring 110 (and capillary action acting in the gap between the surface portion 142a of the nozzle member 142 and the inclined portion 113) can promote the flow of the lubricating oil 126 toward the rolling elements 117. Lubricating oil 126 is supplied between inner ring raceway surface 112 and rolling elements 117. As rolling elements 117 roll on inner ring raceway surface 112 and outer ring raceway surface 116, lubricating oil 126 is also supplied between rolling elements 117 and outer ring 114.

[0101] Furthermore, because lubricating oil 126 can be stored in recess 113r, even if lubricating oil 126 is supplied intermittently from nozzle member 142 as shown in Figure 9, lubricating oil 126 can continue to be supplied from recess 113r to rolling elements 117 and inner ring rolling surface 112. In other words, even while lubricating oil 126 is not being supplied from nozzle member 142, lubricating oil 126 can continue to be supplied from recess 113r to rolling elements 117 and inner ring rolling surface 112.

[0102] Depth D of recess 113r ｒ The depth D of the recess 113r is, for example, 0.1 mm or more and 2 mm or less. Therefore, the lubricating oil 126 can be reliably stored in the recess 113r. ｒ The lower limit of the depth of the recess 113r may be 0.2 mm or 0.3 mm. The upper limit of the depth of the recess 113r may be 1.8 mm, 1.5 mm, or 1.0 mm. ｒis defined as the distance between the intersection of a line extending from the center line of the discharge path 146 at the discharge port 145 with the recess 113r and the intersection of the line with an imaginary plane connecting the inclined surfaces (inclined portions 113) on both sides of the recess 113r. The shape of the recess 113r in a cross section taken along the axial direction of the bearing 102 is not particularly limited, and may be semicircular or V-shaped. The shape of the recess 113r in the cross section may include curves or straight lines.

[0103] The mechanical device of this embodiment has a configuration similar to that of the mechanical device 150 of embodiment 1 (see Figures 7 and 8), but instead of the bearing device 101 of embodiment 1, it has the bearing device 101 of this embodiment.

[0104] In addition to the effects of the lubricating oil supply unit 104, the bearing device 101, and the mechanical device 150 of the first embodiment, the bearing device 101 and the mechanical device of the present embodiment have the following effects.

[0105] In the bearing device 101 and the mechanical device of this embodiment, the inclined portion 113 is provided with a recess 113r that stores the lubricating oil 126. The discharge port 145 faces the recess 113r.

[0106] The lubricating oil 126 can be stored in the recess 113r. Therefore, even if the lubricating oil 126 is intermittently supplied to the interior of the bearing 102 (for example, the inclined portion 113), the lubricating oil 126 can be continuously supplied from the recess 113r to the rolling elements 117 and the inner ring rolling surface 112. This can extend the lubrication life of the bearing device 101 and the bearing 102 included in the mechanical device 150.

[0107] 20 and 21, a lubricant oil supply unit 104 according to a third embodiment will be described. The lubricant oil supply unit 104 according to the present embodiment has a similar configuration to the lubricant oil supply unit 104 according to the first embodiment, but differs mainly in the following respects.

[0108] The lubricant supply unit 104 of this embodiment further includes a float 160. The float 160 is disposed within the tank 125 and is capable of floating relative to the lubricant 126. The float 160 is formed of, for example, a resin such as polycarbonate or rubber, or a metal such as iron or copper. The float 160 presses the lubricant 126 toward the tube 128 and the pump 130 by its own weight. As shown in FIG. 21 , as the lubricant 126 in the tank 125 decreases, the float 160 moves downward, following the liquid level of the lubricant 126. As long as the float 160 can move smoothly within the tank 125, the external shape of the float 160 is not particularly limited and may be, for example, a rectangular parallelepiped, a cylinder, a portion of a sphere, or a ring. The float 160 may also be a hollow member.

[0109] The bearing device and mechanical device of this embodiment have the same configuration as the bearing device 101 (see Figures 1 and 2) and mechanical device 150 (see Figures 7 and 8) of embodiment 1, but instead of the lubricating oil supply unit 104 of embodiment 1, they are equipped with the lubricating oil supply unit 104 of this embodiment.

[0110] The lubricant oil supply unit 104 of this embodiment has the following advantages in addition to the advantages of the lubricant oil supply unit 104 of the first embodiment.

[0111] The lubricant supply unit 104 of this embodiment is disposed in the tank 125 and further includes a float 160 that can float relative to the lubricant 126 .

[0112] The float 160 presses the lubricating oil 126 toward the pump 130 due to its own weight. The lubricating oil 126 remaining in the tank 125 without being used up decreases or disappears. More of the lubricating oil 126 in the tank 125 can be used up. The lubricating oil supply unit 104 of this embodiment can extend the lubrication life of the bearing 102.

[0113] 22 to 24, a lubricant oil supplying unit 104 according to a fourth embodiment will be described. The lubricant oil supplying unit 104 according to the present embodiment has a similar configuration to the lubricant oil supplying unit 104 according to the third embodiment, but differs mainly in the following respects.

[0114] The lubricant supply unit 104 of this embodiment further includes a float 160b. The float 160b may be made of the same material as the float 160.

[0115] The tank 125 includes a stopper 62. The stopper 62 protrudes into the tank 125 and regulates the positions of the floats 160, 160b. The stopper 62 is disposed at the top of the tank 125. In this specification, the stopper 62 being disposed at the top of the tank 125 means that when the bearing device 101 is incorporated into a device (for example, the mechanical device 150 in FIG. 7 ), the stopper 62 is disposed at the top of the lubricating oil supply unit 104 in the vertical direction.

[0116] The tank 125 includes a first tank portion 125a and a second tank portion 125b. In a plan view from the axial direction of the bearing 102 (the axial direction of the lubricating oil supply unit 104), the first tank portion 125a extends counterclockwise from the stopper 62. In a plan view from the axial direction of the bearing 102 (the axial direction of the lubricating oil supply unit 104), the second tank portion 125b extends clockwise from the stopper 62. The lubricating oil 126 is contained in the first tank portion 125a and the second tank portion 125b.

[0117] As shown in FIG. 23 , in the lubricating oil supply unit 104 of the present embodiment, the power supply unit 132 and the tank 125 (second tank portion 125b) are arranged side by side in the axial direction of the bearing 102. Therefore, the tank 125 (second tank portion 125b) can be arranged behind the power supply unit 132. As shown in FIG. 24 , the controller 136 and the tank 125 (second tank portion 125b) are arranged side by side in the axial direction of the bearing 102. Therefore, the tank 125 (second tank portion 125b) can be arranged behind the controller 136. Therefore, the capacity of the tank 125 of the present embodiment can be increased compared to the capacity of the tank 125 of the first embodiment.

[0118] The tube 128 is connected to the first tank portion 125a and the pump 130. The tube 128 may be integrally formed with the first tank portion 125a. The tube 128 may be detachable from the pump 130. The lubricating oil supply unit 104 of the present embodiment further includes a tube 128b. The tube 128b is connected to the second tank portion 125b and the pump 130. The tube 128b may be integrally formed with the second tank portion 125b. The tube 128b may be detachable from the pump 130. When the lubricating oil 126 in the tank 125 runs out, the tube 128 or the tube 128b can be detached from the pump 130 to replenish the lubricating oil 126 in the tank 125 from the tube 128 or the tube 128b.

[0119] When the pump 130 is operating, the pump 130 sucks the lubricating oil 126 in the tank 125 through the tubes 128 and 128b, and delivers the lubricating oil 126 to the supply path member 140. In this way, the lubricating oil 126 is supplied to the inside of the bearing 102.

[0120] The lubricant supply unit 104 of this embodiment further includes a housing 137b. The housing 137b houses the power supply unit 132 and the controller 136. The housing 137b has a similar configuration to the housing 137. The housing 137b includes a housing main body 138b and a lid 139b. The housing main body 138b and the lid 139b may be formed of the same material or different materials.

[0121] The housing body 138b has a cup shape. An opening is provided in the housing body 138b. The outer peripheral surface of the housing body 138b may be fixed to the inner peripheral surface of the outer ring spacer 122. The outer peripheral surface of the housing body 138b may be bonded to the inner peripheral surface of the outer ring spacer 122 with an adhesive such as an epoxy adhesive. The housing body 138b may be fixed to a fixed ring (e.g., the outer ring 114) of the bearing 102. The housing body 138b is spaced from the inner ring spacer 121.

[0122] The lid 139b closes the opening of the housing main body 138b. The lid 139b may be detachable from the housing main body 138b. The lid 139b may be fixed to the housing main body 138b using a detachable fixing member (not shown) such as a screw. The lid 139b can be removed from the housing main body 138b by removing the fixing member. Therefore, a faulty controller 136 can be replaced with a new controller 136, and a faulty power supply unit 132 can be replaced with a new power supply unit 132, without removing the entire lubricant supply unit 104 from the bearing device 101.

[0123] 23 and 24 , the outer ring spacer 122 includes a protrusion 123. The protrusion 123 protrudes from the inner circumferential surface of the outer ring spacer 122 toward the inner ring spacer 121. The protrusion 123 is spaced apart from the inner ring spacer 121. The protrusion 123 is disposed between the housing 137 and the housing 137b in the axial direction of the bearing 102 (the axial direction of the lubricating oil supply unit 104).

[0124] The bearing device and mechanical device of this embodiment have the same configuration as the bearing device 101 (see Figures 1 and 2) and mechanical device 150 (see Figures 7 and 8) of embodiment 1, but instead of the lubricating oil supply unit 104 of embodiment 1, they are equipped with the lubricating oil supply unit 104 of this embodiment.

[0125] The lubricant oil supply unit 104 of this embodiment has the following advantages in addition to the advantages of the lubricant oil supply unit 104 of the first embodiment.

[0126] In the lubricant oil supply unit 104 of this embodiment, the controller 136 and the tank 125 (second tank portion 125 b ) are arranged side by side in the axial direction of the bearing 102 .

[0127] Since the tank 125 can be disposed on the rear surface of the controller 136, the capacity of the tank 125 is increased. The lubricating oil 126 can be supplied to the inside of the bearing 102 for a longer period of time. The lubrication life of the bearing 102 can be further extended.

[0128] The lubricating oil supply unit 104 of the present embodiment further includes a power supply unit 132 that generates electricity and supplies the electricity to the controller 136. The power supply unit 132 and the tank 125 (second tank portion 125b) are arranged side by side in the axial direction of the bearing 102.

[0129] Since the tank 125 can be disposed on the rear side of the power supply unit 132, the capacity of the tank 125 is increased. The lubricating oil 126 can be supplied to the inside of the bearing 102 for a longer period of time. The lubrication life of the bearing 102 can be further extended.

[0130] (Embodiment 5) <Configuration of Bearing Device> Fig. 25 is a schematic side view of a bearing device according to this embodiment. Fig. 26 is a schematic cross-sectional view of a portion along line A-A in Fig. 25 in embodiment 5. With reference to Figs. 25 and 26, bearing device 10 according to this embodiment is a rolling bearing device. Bearing device 10 includes bearing 11, which is a rolling bearing, and lubricant supply unit 20 (lubricant supply mechanism). Lubricant supply unit 20 supplies lubricant to bearing 11. A center line L0 passing through the center of bearing 11, which has an annular shape, extends in the left-right direction in Fig. 26, i.e., in the axial direction. The lubricant supply units 20 are arranged adjacent to each other in the axial direction of bearing 11, i.e., in the direction in which center line L0 extends.

[0131] The lubricating oil supply unit 20 is incorporated between an outer ring spacer 33 and an inner ring spacer 34 that are abutted against one axial end of the bearing 11. In this sense, the outer ring spacer 33 and the inner ring spacer 34 are not included in the lubricating oil supply unit 20. However, the lubricating oil supply unit 20 may also be considered to include the outer ring spacer 33 and the inner ring spacer 34. For example, the lubricating oil supply unit 20, the outer ring spacer 33, and the inner ring spacer 34 may be integrated together.

[0132] The bearing device 10, which includes the bearing 11 and the lubricating oil supply unit 20, is used by being installed in a mechanical device, for example, between a rotating shaft and a spindle housing. When the bearing device 10 is installed in a mechanical device, for example, another spacer may be abutted against the other end of the bearing 11. In this case, the bearing 11 can be positioned in the axial direction by the outer ring spacer 33, inner ring spacer 34, and other spacers.

[0133] The bearing 11 mainly comprises an outer ring 13, an inner ring 14, multiple rolling elements 15, a cage 16, and a sealing member. The outer ring 13 is, for example, a fixed raceway. However, the outer ring 13 may also be a rotating raceway. The inner ring 14 is, for example, a rotating raceway. However, the inner ring 14 may also be a fixed raceway. The multiple rolling elements 15 are interposed between the inner ring 14 and the outer ring 13. The multiple rolling elements 15 are arranged on an annular track with spacing between them in the circumferential direction. The circumferential direction is the direction in which the circumference of the annular shape of the inner ring 14 extends. The cage 16 holds the multiple rolling elements 15 at regular intervals. The sealing member is located on the outer periphery of the cage 16. The bearing 11 may be, for example, an angular contact ball bearing, a deep groove ball bearing, or a cylindrical roller bearing. The bearing 11 is pre-filled with a desired grease. The sealing member is disposed at the end opposite to the side where the outer ring spacer 33 and the like are disposed.

[0134] The outer ring 13 of the bearing 11 has an outer ring rolling surface formed on its inner peripheral surface with which the rolling elements 15 come into contact. The inner ring 14 of the bearing 11 has an inner ring rolling surface formed on its outer peripheral surface with which the rolling elements 15 come into contact. The inner ring rolling surface faces the outer ring rolling surface. Therefore, the inner ring 14 is disposed radially inside the outer ring 13. The outer peripheral surface also includes an inclined portion 14a that continues to the inner ring rolling surface. The inclined portion 14a is inclined with respect to the axial direction so as to approach the outer ring 13 from the axial end of the inner ring 14 toward the inner ring rolling surface.

[0135] The cage 16 of the bearing 11 has a cage inner diameter surface 16b. The cage inner diameter surface 16b is a surface formed on the inner diameter side in the radial direction of the surface of the cage 16. The radial direction refers to a direction extending radially from the center of the annular nozzle member 37 toward the periphery to form a diameter (radius).

[0136] The cage inner diameter surface 16b extends from the end portion in the axial direction of the bearing 11 toward the center. In the cross section along the axial direction of the bearing 11 shown in Figure 26, the shape of the cage inner diameter surface 16b may be linear. For example, in Figure 26, the cage inner diameter surface 16b is linear extending along the axial direction. As shown in the cross section of Figure 26, the cage inner diameter surface 16b may have a linear taper at both axial ends such that the diameter increases axially outward. Note that the cage inner diameter surface 16b may also be curved and concave toward the outer periphery of the bearing 11.

[0137] The spacer is made up of an outer ring spacer 33 and an inner ring spacer 34. In the axial direction, one end of the outer ring 13 contacts and is connected to the outer ring spacer 33. In the axial direction, one end of the inner ring 14 contacts and is connected to the inner ring spacer 34. Here, one end of the outer ring 13 (inner ring 14) means the end located on the left side of the bearing 11 in the axial direction. In addition, in the axial direction, a part of the outer circumference of the housing main body 21 that constitutes the lubricating oil supply unit 20 faces the outer ring 13. In this way, the lubricating oil supply unit 20 is connected to the bearing 11.

[0138] The lubricant oil supply unit 20 mainly includes a housing, and a power generation unit 25, a power supply circuit 26, a control circuit 27, a drive circuit 28, a pump 29, and a lubricant oil tank 30, which are arranged circumferentially within the housing. The housing is annular. The housing is composed of a housing main body 21 and a lid 22. In the cross section shown in FIG. 26 , the housing main body 21 is cup-shaped with an opening on the surface opposite the bearing 11. The lid 22 is detachable from the housing main body 21 and closes the opening of the housing main body 21.

[0139] The power supply circuit 26 may include a charging unit. The lubricating oil tank 30 (retention unit) stores (holds) the same type of lubricating oil as the base oil of the grease pre-sealed in the bearing 11. "Pre-sealed in the bearing 11" here means that the lubricating oil is stored (held) in the bearing 11 before being supplied by the lubricating oil tank 30. The power generation unit 25, power supply circuit 26, control circuit 27, drive circuit 28, pump 29, and lubricating oil tank 30 are arranged circumferentially inside the housing main body 21. The power generation unit 25 is connected to the power supply circuit 26. The power supply circuit 26 is connected to the control circuit 27. The control circuit 27 is connected to the drive circuit 28. The drive circuit 28 is a circuit for operating a pump 29, such as a micropump. The pump 29, connected to the drive circuit 28, is connected to a suction tube 31 connected to the bag of the lubricating oil tank 30 and a discharge tube 32 for supplying lubricating oil from the pump 29 to the inside of the bearing 11.

[0140] 26, a nozzle member 37 is connected to the tip of the discharge tube 32. The tip of the discharge tube 32 is the end of the discharge tube 32 opposite the base portion connected to the pump 29. A nozzle hole 37a (hole portion) connected to the discharge tube 32 is formed inside the nozzle member 37.

[0141] The nozzle member 37 is connected to the annular housing of the lubricating oil supply unit 20. The nozzle member 37 is connected to the surface of the housing main body 21 that faces the bearing 11. As a result, the nozzle member 37 may be disposed, for example, entirely inside the bearing 11, i.e., in the space between the outer ring 13 and the inner ring 14. Within this space in the bearing 11, the entire nozzle member 37 is accommodated in a position axially adjacent to the rolling elements 15. However, the nozzle member 37 is not limited to this configuration.

[0142] Furthermore, a ring-shaped sealing groove 41 is formed in the surface of the nozzle member 37 that is connected to the housing main body 21 so as to surround the nozzle hole 37a. A sealing member 42 is disposed inside the sealing groove 41. The sealing member 42 is provided to prevent the lubricating oil supplied from the discharge tube 32 to the nozzle hole 37a from leaking to the outside from the joint surface between the nozzle member 37 and the housing main body 21.

[0143] The power generating unit 25 of the lubricating oil supply unit 20 may be, for example, one that generates power by the Seebeck effect. Specifically, the power generating unit 25 has a first thermal conductor 23a, a second thermal conductor 23b, and a thermoelectric element 24. The first thermal conductor 23a is connected to the outer ring spacer 33. The second thermal conductor 23b is disposed closer to the inner ring spacer 34 (inward in the radial direction) than the first thermal conductor 23a. The thermoelectric element 24 is disposed so as to connect between the first thermal conductor 23a and the second thermal conductor 23b. The thermoelectric element 24 is fixed in close contact with the first thermal conductor 23a and the second thermal conductor 23b. The thermoelectric element 24 is an element that utilizes the Seebeck effect of a Peltier element.

[0144] During use, the temperatures of the inner ring 14 and the outer ring 13 rise due to frictional heat with the rolling elements 15. Since the outer ring 13 is typically incorporated into the housing of the device, heat is dissipated by thermal conduction. This results in a temperature difference between the inner ring 14 and the outer ring 13. The temperature of the inner ring 14 is higher than that of the outer ring 13. The temperature of the outer ring 13 is conducted to the first thermal conductor 23a, and the temperature of the inner ring 14 is conducted to the second thermal conductor 23b. The first thermal conductor 23a and the second thermal conductor 23b are arranged to penetrate the inner and outer circumferential surfaces of the housing main body 21, respectively. This results in a temperature difference between the first thermal conductor 23a and the second thermal conductor 23b. This results in a temperature difference between both end faces of the thermoelectric element 24, which is arranged between the first thermal conductor 23a and the second thermal conductor 23b. This allows the thermoelectric element 24 to generate electricity through the Seebeck effect.

[0145] The inner peripheral surface of the outer ring spacer 33 and the outer peripheral surface of the first heat conductor 23a are in close contact with each other. On the other hand, the inner peripheral surface of the second heat conductor 23b on the inner ring side (the surface facing the inner ring spacer 34) is not in contact with the inner ring spacer 34. A gap 36 may be formed between the housing body 21 and the inner ring spacer 34.

[0146] The electric charge generated (or generated) by the power generation unit 25 is stored in the power supply circuit 26. Specifically, the electric charge is stored in a storage unit such as a storage battery or a capacitor included in the power supply circuit 26 (also called a storage circuit). It is preferable to use an electric double layer capacitor (capacitor) as the capacitor.

[0147] The control circuit 27 is a control unit for controlling the operation of the pump 29 via the drive circuit 28. The control circuit 27 includes a program storage unit that stores a control program and a calculation unit (microcomputer) that is connected to the program storage unit and executes the control program. The control circuit 27 can be used to preset the start time of lubricating oil supply to the bearing 11, the supply timing (interval), the drive time of the pump 29 for supplying lubricating oil, the amount of lubricating oil to be supplied, and other settings. By maintaining an appropriate lubricating oil supply state in this manner, the lubrication life of the bearing device can be extended.

[0148] Additionally, the control circuit 27 acquires data relating to the supply status of lubricating oil in the lubricating oil supply unit 20. The control circuit 27 is also capable of outputting the data to the outside of the control circuit 27 (for example, to an output board 56 (see FIG. 42) as a receiving unit).

[0149] The drive circuit 28 may include, for example, any sensors (bearing temperature sensor, bearing rotation sensor, lubricant remaining amount sensor, lubricant temperature sensor, etc.) Signals from these sensors may be input to a calculation unit (microcomputer) of the drive circuit 28, which may automatically control the pump 29 according to the temperature of the bearing 11 and its rotation status, thereby adjusting the amount of lubricant supplied.

[0150] The pump 29 is controlled by the control circuit 27 via the drive circuit 28. The pump 29 sucks the lubricating oil from the lubricating oil tank 30 through the suction tube 31, and supplies the sucked lubricating oil to the inside of the bearing 11 through the discharge tube 32 and the nozzle hole 37a (nozzle member 37).

[0151] The housing cover 22 may be fixed to the housing main body 21 by screws, which are an example of fixing members. The cover 22 can be removed by removing the screws, which serve as fixing members, from the tapped holes 35 to which the screws are fixed. In this way, the lubricating oil tank 30 housed in the housing main body 21 can be refilled with lubricating oil without removing the entire lubricating oil supply unit 20 from the bearing device 10.

[0152] Next, the lubricating oil tank 30 housed in the housing main body 21 may be configured as a flexible resin bag. The lubricating oil tank 30 may be arranged in an arc shape along the annular housing main body 21.

[0153] The resin bag constituting the lubricating oil tank 30 may be formed by, for example, stacking resin sheets and heat-welding the outer periphery. The outer periphery of the lubricating oil tank 30 may be the heat-welded portion.

[0154] The bag of the lubricating oil tank 30 is provided with a suction tube 31 that connects to the pump 29. When the bag of the lubricating oil tank 30 is formed by heat welding, the suction tube 31 is sandwiched between the overlapping resin sheets to form the bag, and heat-welded. In this way, the suction tube 31 can be integrated with the bag.

[0155] Figure 27 is an enlarged schematic cross-sectional view of region XXVII surrounded by a dotted line in Figure 26. That is, Figure 27 is a schematic cross-sectional view showing the positional relationship between the nozzle member in embodiment 5, the lubricating oil supplied therefrom, and the cage that the nozzle member faces. Referring to Figure 27 in addition to Figures 25 and 26, nozzle member 37 supplies lubricating oil (grease base oil) from lubricating oil tank 30 to the inside of bearing 11. To this end, nozzle member 37 has a nozzle hole 37a therein and a land portion 37b as its tip surface.

[0156] The nozzle hole 37a is a flow path through the nozzle member 37 for lubricating oil that has flowed from the lubricating oil tank 30 to the discharge tube 32 to be supplied to the inside of the bearing 11. One nozzle hole 37a is provided in the nozzle member 37. In this embodiment, as shown in Figure 27, the nozzle member 37 is installed so that lubricating oil is discharged vertically upward from one nozzle hole 37a. To achieve this, the discharge tube 32 and the nozzle hole 37a are positioned vertically above the center line L0.

[0157] The land portion 37b is a surface that constitutes the most downstream position of the lubricating oil passing through the nozzle hole 37a in the nozzle member 37. The lubricating oil is discharged from the most downstream portion of the nozzle hole 37a formed in the land portion 37b. In other words, the nozzle hole 37a is formed to reach the land portion 37b.

[0158] The land portion 37b is a flat surface on which the lubricating oil forms oil droplets. That is, as shown in FIG. 27 , after flowing through the nozzle hole 37a, the lubricating oil is discharged from the land portion 37b to the outside of the nozzle member 37. The land portion 37b is the surface at the boundary between the inside of the nozzle member 37 and the outside of the nozzle member 37. The outside of the nozzle member 37 is the space within the bearing 11, particularly the space sandwiched between the outer ring 13 and the inner ring 14. The lubricating oil can form oil droplets 38 toward the land portion 37b and the cage inner diameter surface 16b. The oil droplets 38 are, for example, hemispherical. The land portion 37b has such conditions, such as shape, material, and position.

[0159] The land portion 37b in this embodiment is defined. The land portion 37b is a plane of the nozzle member 37 that faces the cage inner diameter surface 16b and where the discharge port of the nozzle hole 37a is formed. The land portion 37b is a plane where the center line L1 and the line L2 intersect in a cross section along the center line L0. The discharge port of the nozzle hole 37a is an outlet from the nozzle member 37 for the lubricating oil that has flowed through the nozzle hole 37a. In other words, the discharge port is the most downstream portion of the nozzle hole 37a in the nozzle member 37. Therefore, the land portion 37b may be considered to include the discharge port of the nozzle hole 37a. The center line L1 is a line that passes through the center of a cross section of the discharge port of the nozzle hole 37a that is perpendicular to the extension direction of the nozzle hole 37a. Therefore, if the cross section of the nozzle hole 37a is circular, the center line L1 is the center of the circle at the discharge port. The line L2 corresponds to a tangent extending along the cage inner diameter surface 16b. In FIG. 27, the line L2 is axially aligned. That is, in the cross section along the axial direction as shown in FIG. 27, the straight line L2 represents the cage inner diameter surface 16b.

[0160] It is preferable that the plane of the land portion 37b be substantially uncurved in the vertical direction (direction perpendicular to the main surface) that forms the unevenness, and that the cross section of the land portion 37b be a straight line. Note that in the cross section of the present embodiment, at least a portion of the land portion 37b extends parallel to the cage inner diameter surface 16b in the cross section shown in Figure 26.

[0161] The land portion 37b facing the cage inner diameter surface 16b is disposed so that a portion of the land portion 37b overlaps with the portion of the cage inner diameter surface 16b that expands (extends) in the axial direction when viewed from the radial direction. In Fig. 27, the entire axially extending land portion 37b may face the cage inner diameter surface 16b so as to be parallel to the cage inner diameter surface 16b. However, a portion of the land portion 37b may face, for example, the tapered portions at both axial ends of the cage inner diameter surface 16b in the radial direction.

[0162] In the cross section (along the axial direction) of Figure 26, the straight line of the land portion 37b and the straight line L2 extending along the cage inner diameter surface 16b do not extend in opposite directions. For example, in the cross section of Figure 26, the land portion 37b does not extend from the upper right to the lower left, and the cage inner diameter surface 16b does not extend from the lower right to the upper left. This makes it possible for oil droplets 38 to easily form between the land portion 37b and the cage inner diameter surface 16b.

[0163] The angle θ1 is defined as the angle at which the center line L1 of the nozzle hole 37a intersects with the cage inner diameter surface 16b on the lubricant supply unit 20 side in the axial direction (left side in FIGS. 26 and 27). The angle θ1 is greater than 0° and equal to or less than 90°. The angle θ1 is an acute angle formed at the intersection P between the center line L1 and the straight line L2 on the lubricant supply unit 20 side in the axial direction (left side in FIG. 27), as shown in FIG. 27. However, the angle θ1 is not limited to this, and may be formed on the opposite side from the lubricant supply unit 20 (right side in FIG. 27).

[0164] The intersection point between the land portion 37b and the center line L1 is designated as Q. The intersection point Q is the point where the center line L1 intersects with the discharge port of the nozzle hole 37a of the land portion 37b in particular. The distance in the radial direction (the vertical direction in FIG. 27 ) between the intersection point Q and the above-mentioned intersection point P is designated as the distance h. In FIG. 27 , the distance h is the distance between the land portion 37b and the cage inner diameter surface 16b. In the cross-sectional view of FIG. 27 , the distance h between the straight line of the land portion 37b and the straight line of the cage inner diameter surface 16b is preferably 0.1 mm or more and 5 mm or less.

[0165] Fig. 28 is a schematic perspective view of a circular ring-shaped nozzle member in embodiment 5. Referring to Fig. 28, nozzle member 37 may be circular ring-shaped. In this case, nozzle member 37 is entirely contained within bearing 11 in the space sandwiched between outer ring 13 and inner ring 14 (on the axial side of lubricating oil supply unit 20).

[0166] Figure 29 is an enlarged perspective schematic diagram of a first example of region B surrounded by a dotted line in Figure 28. Referring to Figure 29, the nozzle member 37 may be a block-shaped member obtained by cutting out a portion of the annular member shown in Figure 28. The block-shaped nozzle member 37 is cut out along the circumferential direction. In other words, the nozzle member 37 shown in Figure 29 is cut out only partially in the circumferential direction, so that the entire nozzle member remains without being cut out in the radial and axial directions. Therefore, the block-shaped nozzle member 37B1 shown in Figure 29 is cut so that end faces TR at both circumferential ends are perpendicular to the outermost radial surface.

[0167] 28 and 29, the nozzle member 37 of this embodiment is formed from a resin material. The nozzle member 37 is more preferably formed from PTFE (polytetrafluoroethylene). In particular, it is preferable that at least the land portion 37b of the nozzle member 37 is formed from the resin material (PTFE).

[0168] Figure 30 is a perspective schematic diagram further enlarging the area on the arrow side of line segment XXX-XXX in Figure 29 compared to Figure 29. The annular nozzle member 37 in Figure 28 and the block-shaped nozzle member 37B1 in Figures 29 and 30, in which a portion of the nozzle member 37 is cut away, have the shapes shown in Figures 29 and 30. With particular reference to Figures 29 and 30, the nozzle members 37 and 37B1 have an outermost shaft surface 37OS on the axially outer side (outermost portion), i.e., on the side facing the lubricant supply unit 20. The nozzle members 37 and 37B1 have two innermost shaft surfaces 37IS1 and 37IS2 on the axially inner side (innermost portion), i.e., on the side opposite the lubricant supply unit 20 (rolling element 15 side).

[0169] At least a portion of the shaft outermost surface 37OS is in contact with the housing main body 21. Alternatively, a portion of the shaft outermost surface 37OS can come into contact with the housing main body 21. The shaft outermost surface 37OS has a shape that is curved like an arc when viewed in a plan view from the radial direction, for example. Therefore, the shaft outermost surface 37OS can come into contact with the outer surface of the housing main body 21 so that the contact portion of the shaft outermost surface 37OS is on a straight line extending in the radial direction. Therefore, the shaft outermost surface 37OS extends and spreads generally along the radial direction.

[0170] The innermost shaft surface 37IS1 is formed on the radially outer side (upper side in FIG. 26 ) of the surface facing the rolling elements 15 in the axial direction (facing the rolling elements 15). The innermost shaft surface 37IS2 is formed on the radially inner side (lower side in FIG. 26 ) of the surface facing the rolling elements 15. Both the innermost shaft surfaces 37IS1 and 37IS2 have arc-shaped curves when viewed radially from above. The innermost shaft surface 37IS1 may be inclined so that the axial distance from the outermost shaft surface 37OS gradually increases from the outer side to the inner side in the radial direction. However, although not shown, the axial distance from the innermost shaft surface 37IS1 to the outermost shaft surface 37OS may be substantially constant (the same) from the outer side to the inner side in the radial direction. In this case, in FIG. 26 , the innermost shaft surface 37IS1 is substantially parallel to the outermost shaft surface 37OS.

[0171] The axial distance of the innermost axial surface 37IS2 from the outermost axial surface 37OS is substantially constant (the same) from the radial outside to the radial inside. However, similar to the innermost axial surface 37IS1, the innermost axial surface 37IS2 may also be inclined so that the axial distance from the outermost axial surface 37OS gradually increases from the radial outside to the radial inside.

[0172] The radially innermost side of the innermost axial surface 37IS1 and the radially outermost side of the innermost axial surface 37IS2 have approximately the same radial coordinate. A surface facing radially outward is formed between the innermost axial surface 37IS1 and the innermost axial surface 37IS2, connecting them. This surface is the land portion forming surface 37bb. Of the land portion forming surface 37bb, the flat portion on which the nozzle hole 37a is formed is the land portion 37b. It is preferable that the land portion 37b protrudes upward relative to the land portion forming surface 37bb. If the land portion 37b protrudes upward, a radial step may be formed between the land portion 37b and the land portion forming surface 37bb, and the land portion 37b may be independent from the land portion forming surface 37bb.

[0173] In the first example shown in FIGS. 29 and 30 , the planar shape of the land portion 37b is rectangular. However, referring to FIG. 31 , the planar shape of the land portion 37b may be circular. Alternatively, referring to FIG. 32 , the planar shape of the land portion 37b may be triangular. Furthermore, referring to FIG. 33 , the planar shape of the land portion 37b may be polygonal with four or more vertices. Specifically, the land portion 37b may be hexagonal as shown in FIG. 33 . Alternatively, the planar shape of the land portion 37b may be pentagonal or rhombic. In either case, in FIG. 33 , the planar shape of the land portion 37b is a polygon with four or more vertices and all interior angles less than 180°. FIG. 31 is an enlarged perspective schematic diagram of a second example of the region B surrounded by the dotted line in FIG. 28 . FIG. 32 is an enlarged perspective schematic diagram of a third example of the region B surrounded by the dotted line in FIG. 28 . Fig. 33 is an enlarged perspective schematic view of a fourth example of an area B surrounded by a dotted line in Fig. 28. Figs. 31, 32 and 33 are similar to the first example of Fig. 29 except for the planar shape of land portion 37b, and therefore description thereof will not be repeated here.

[0174] If the radially innermost axially innermost surface 37IS1 and the radially outermost axially innermost surface 37IS2 have the same radial coordinate, the land portion 37b in FIG. 26 is parallel to the center line L0. In particular, when the cage inner diameter surface 16b extends along the axial direction, the land portion 37b is preferably substantially parallel to (along) the center line L0. However, when the cage inner diameter surface 16b is inclined with respect to the axial direction, the cage inner diameter surface 16b may have an inclination angle with respect to the center line L0. This allows the center line L1 (see FIG. 27) of the nozzle hole 37a at the land portion 37b to intersect with the cross section (tangent) of the cage inner diameter surface 16b. Alternatively, this allows the land portion 37b to face the cage inner diameter surface 16b in a parallel relationship. The land portion forming surface 37bb is curved in an arc shape when viewed from the radially outer side. This is because the block-shaped nozzle member 37B1 is part of the annular nozzle member 37. The land portion forming surface 37bb of the nozzle member 37 has an annular shape.

[0175] As shown on land portion 37b in Fig. 29 and in cross section CR in Fig. 30, nozzle hole 37a enters the nozzle member from outermost shaft surface 37OS and bends, for example, at an angle close to a right angle within the nozzle member. From the bent portion, nozzle hole 37a extends to reach land portion 37b.

[0176] The nozzle member 37, 37B1 has a radially outermost surface 37OF on the radially outer side (outermost portion). The nozzle member 37, 37B1 has a radially innermost surface 37IF on the radially inner side (innermost portion), i.e., on the opposite side from the radially outermost surface 37OF. The radially outermost surface 37OF extends in the axial direction to connect the axially outermost surface 37OS to the axially innermost surface 37IS1. The radially innermost surface 37IF extends in the axial direction to connect the axially outermost surface 37OS to the axially innermost surface 37IS2. The radially outermost surface 37OF and the radially innermost surface 37IF may be curved in an arc shape when viewed in a radial plan view. When viewed in a radial plan view, the radially innermost surface 37IF overlaps both the radially outermost surface 37OF and the land portion forming surface 37bb. Therefore, the area of ​​the radially innermost surface 37IF is approximately equal to the sum of the areas of the radially outermost surface 37OF and the land portion forming surface 37bb. In other words, the area of ​​the radially innermost surface 37IF is larger than that of the radially outermost surface 37OF.

[0177] <Operation of Bearing Device> In the bearing device 10 including the bearing 11 and the lubricating oil supply unit 20, the operation of the pump 29 is controlled by the control circuit 27. This allows lubricating oil to be supplied from the lubricating oil tank 30 to the bearing 11.

[0178] The lubricating oil supplied to the inside of the bearing 11 through the nozzle holes 37a is temporarily stored in the area between the cage inner diameter surface 16b and the land portion 37b. The lubricating oil then flows from this area toward the rolling elements 15 due to centrifugal force caused by the rotation of the inner ring 14 and capillary action. In this way, the lubricating oil supplied to the inside of the bearing 11 is supplied to the contact areas between the rolling elements 15 and the inner ring 14 and outer ring 13. As a result, the lubricating performance of the bearing 11 can be maintained for a long period of time.

[0179] Pump 29 is driven when the power generated by power generation unit 25 is stored in a power storage unit (e.g., a capacitor) in power supply circuit 26 and the voltage of the power storage unit reaches a certain voltage. In other words, pump 29 is driven by the power stored in power supply circuit 26 being supplied to control circuit 27. This is because power supply circuit 26, control circuit 27, drive circuit 28, and pump 29 are all connected in series.

[0180] <Operations and Effects> Next, operations and effects of the present embodiment will be described, while appropriately touching upon the background art, etc. Note that the description in this section may partially overlap with the description in the section on the configuration of the bearing device described above.

[0181] The bearing device of this embodiment includes a bearing 11 and a lubricant supply unit 20 that supplies lubricant to the bearing 11. The bearing 11 includes a plurality of rolling elements 15 and a cage 16. The rolling elements 15 are arranged in a circular track. The cage 16 holds the rolling elements 15. The cage 16 has a cage inner diameter surface 16b formed on the inner diameter side in the radial direction. The lubricant supply unit 20 includes a holding portion (lubricant tank 30) and nozzle members 37, 37B1. The lubricant tank 30 holds lubricant to be supplied to the interior of the bearing 11. The nozzle members 37, 37B1 supply lubricant from the lubricant tank 30 to the interior of the bearing 11. The nozzle members 37, 37B1 have a tip surface (land portion 37b). The land portion 37b is a flat surface that allows the lubricant to form oil droplets 38 toward the cage inner diameter surface 16b.

[0182] When the lubricating oil supply unit 20 is activated, the lubricating oil passes through the inside of the nozzle member and forms oil droplets 38 at the discharge port. The expanded oil droplets 38 come into contact with the cage inner diameter surface 16b. In other words, the lubricating oil discharged from the nozzle member becomes the oil droplets 38 shown in FIG. 27 on the cage inner diameter surface 16b. In this way, the oil droplets 38 spread over the surface of the cage 16 due to capillary action. Then, as the rotating ring (e.g., inner ring 14) of the bearing 11 rotates, the lubricating oil reaches the rolling elements 15 from the pocket surfaces of the cage 16. The lubricating oil then reaches the raceway surfaces of the outer ring 13 and inner ring 14 from the rolling elements 15.

[0183] Oil is supplied from the lubricating oil tank 30 so that oil droplets 38 are formed between the land portion 37b and the cage inner diameter surface 16b. By supplying an optimal amount of oil droplets 38, which is smaller than the large amount of air oil that is discharged, lubricating oil is smoothly supplied to the entire interior of the bearing 11. This improves the lubrication durability of the bearing 11. In other words, according to this embodiment, the oil droplets 38 can efficiently replenish oil that is insufficient in the rolling contact portion. This allows the capacity of the lubricating oil tank 30 of the lubricating oil supply unit 20 to be made compact. Furthermore, in this embodiment, the lubricating durability of the bearing 11 can be improved by supplying a small amount of lubricating oil with high efficiency.

[0184] When the bearing device 10 rotates at high speeds, heat generated by the bearing 11 accelerates the deterioration of the lubricating oil. This can cause a problem in that the lubrication durability of the bearing 11 cannot be ensured even at rotational speeds lower than the maximum rotational speed at which the bearing 11 can be used. On the other hand, there is a demand in the market for even higher rotational speeds, that is, for improving the lubrication durability of the bearing 11 under high-speed rotation. According to this embodiment, the lubrication durability of the bearing 11 can be improved even when the bearing 11 rotates at high speeds.

[0185] Compressed air is used to supply air-oil to the desired area. That is, the lubricating oil is sent using the pressure of the compressed air. However, there are situations where using air-oil is not desirable, such as when miniaturizing the equipment. In such situations, compressed air is not used, and instead, oil droplets 38 are formed as in this embodiment, and the surface tension of the oil droplets 38 is used to partially adhere to the mating surface, i.e., the cage inner diameter surface 16b. This draws the lubricating oil toward the cage 16. This eliminates the need for a large housing and tank for air-oil, and eliminates the need to enlarge the equipment. As described above, this embodiment allows for smooth supply of lubricating oil to the rolling contact parts without enlarging the equipment.

[0186] In the bearing device 10, the nozzle members 37, 37B1 may be formed from a resin material. Resin materials have excellent oil repellency. Therefore, if the nozzle member 37 is made of a resin material, the lubricating oil discharged from the nozzle holes 37a at the land portions 37b can be formed into droplets as shown in FIG. 27. In particular, if the nozzle member 37 is made of PTFE, its high oil repellency can more reliably form the lubricating oil into droplets.

[0187] The oil droplets 38 supplied from the nozzle member 37 to the cage inner diameter surface 16b are required to be deposited on the cage inner diameter surface 16b due to surface tension. From the viewpoint of facilitating the deposition of lubricating oil on the cage inner diameter surface 16b, a shorter distance h between the land portion 37b and the cage inner diameter surface 16b shown in FIG. 27 is preferable. However, shortening the distance h may result in a problem in which the land portion 37b and the cage inner diameter surface 16b interfere with (collide with) each other. On the other hand, increasing the distance h creates a trade-off problem in that it becomes more difficult for the lubricating oil (oil droplets 38) to reach the cage 16 side from the nozzle member 37. Therefore, by increasing the oil repellency of the nozzle member 37 as described above, the high surface tension of the oil droplets 38 makes it easier for the oil droplets 38 to deposit on the cage inner diameter surface 16b even if the distance h is long. From this viewpoint, the distance h is preferably set to be 0.1 mm or more and 5 mm or less.

[0188] Furthermore, the nozzle member 37 is made of a resin material, which makes it easier to form the nozzle holes 37a than when the nozzle member 37 is made of a metal that is harder than a resin material.

[0189] In the bearing device 10, the nozzle member may be either annular (nozzle member 37) or block-shaped (nozzle member 37B1) with a circumferentially cut-away portion of the annular shape. In other words, the nozzle member 37 is annular rather than elongated. In this way, the swirling flow and the flow of adhering grease around the discharge port of the nozzle hole 37a can be controlled. By controlling these flows, the formation of oil droplets 38 at the discharge port can be prevented from being hindered.

[0190] If the nozzle member 37B1 is block-shaped, it will have the same effects as the annular nozzle member 37, and also have the following effect. Referring to Figure 29, the nozzle member 37B1, in which only a portion of the circumferential area of ​​the nozzle member 37 is cut away, allows the lubricating oil 38A to easily flow from the inside to the outside of the nozzle member 37B1, as shown by the arrows in the figure. Therefore, it is possible to prevent the lubricating oil from unintentionally accumulating inside the inner ring 14 (around the rotating shaft).

[0191] It is preferable that the nozzle member body is not located in any other area except for the land portion 37b, which contributes to the discharge of lubricating oil. The nozzle member body located in any other area would obstruct the flow of lubricating oil 38A shown in FIG. 29. There is also the possibility that the body may unintentionally interfere with other components. Therefore, the nozzle member 37B1 is made block-shaped, with its volume smaller than that of the nozzle member 37. This reduces the possibility of the nozzle member 37B1 unintentionally interfering with other components.

[0192] In the bearing device 10, the nozzle member 37, 37B1 is formed with a hole (nozzle hole 37a) that reaches the tip end surface (land portion 37b). The nozzle hole 37a circulates and discharges lubricating oil to be supplied to the inside of the bearing 11. In a cross section along the axial direction, the center line L1 of the nozzle hole 37a intersects with the cage inner diameter surface 16b (straight line L2). The angle θ1 at which the center line L1 of the nozzle hole 37a on the lubricating oil supply unit 20 side in the axial direction intersects with the cage inner diameter surface 16b (straight line L2) is greater than 0° and equal to or less than 90°.

[0193] The shorter the path from the lubricating oil supply unit 20 to the discharge port of the nozzle member, the smaller the pressure loss in the nozzle hole 37a. Therefore, the shorter the path, the smoother the lubricating oil is delivered to the discharge port. From this perspective, it is preferable that the angle θ1 formed by the intersection of the center line L1 and the straight line L2 in Figure 27 is greater than 0° and less than 90°.

[0194] In the bearing device 10, the planar shape of the land portion 37b is either a circle or a triangle. In the bearing device 10, the planar shape of the land portion 37b is a polygon with four or more vertices. In this way, the nozzle member 37 has the land portion 37b that extends as a flat surface. Therefore, the oil droplets 38 discharged from the land portion 37b have a height h sufficient to easily reach the cage inner diameter surface 16b.

[0195] The land portion 37b protrudes upward (radially outward) relative to the land portion forming surface 37bb. This prevents the flat surface of the land portion 37b from being significantly larger than the size of the oil droplet 38. In other words, the land portion 37b has a boundary with the land portion forming surface 37bb at a position slightly away from the outer edge of the nozzle hole 37a. If the land portion 37b were significantly larger than the nozzle hole 37a, the oil droplet 38 would not rise in the direction of height h and would instead spread along the large flat surface of the land portion 37b. This prevents the oil droplet 38 from smoothly reaching the cage 16. However, in this embodiment, the land portion 37b has a relatively small flat surface. This allows the oil droplet 38 to smoothly reach the cage 16 from the land portion 37b.

[0196] In the above-described bearing device 10, the bearing 11 is pre-filled with lubricating oil. The lubricating oil is grease. This allows for applications where air-oil lubrication is undesirable. For example, grease lubrication is increasingly being used instead of air-oil lubrication for machine tool spindle bearings. This is intended to reduce environmental impact and costs. Grease lubrication eliminates the need for the lubricating oil tank and lubricating oil supply device used in air-oil lubrication. The lubricating oil tank used in air-oil lubrication is large, and the lubricating oil supply device is a complex device with a pump that has a forced discharge function. Therefore, grease lubrication allows for a more compact facility compared to air-oil lubrication. Furthermore, grease lubrication uses less lubricating oil than air-oil lubrication. Therefore, grease lubrication is environmentally friendly and reduces initial and running costs.

[0197] In the case of a grease-lubricated bearing, application of this embodiment facilitates the separation of grease adhering to the cage bore surface 16b. In other words, capillary action actively acts on the liquid lubricating oil adhering to the cage bore surface 16b. This allows the liquid lubricating oil to sufficiently reach the rolling surfaces inside the bearing 11 when the grease is depleted, i.e., when there is little grease.

[0198] Sixth Embodiment In a sixth embodiment, the same configurations, features, materials, etc. as those in the fifth embodiment will not be described repeatedly unless it is preferable to do so again.

[0199] <Configuration of Bearing Device> Figure 34 is a schematic cross-sectional view of a portion of embodiment 6 taken along line A-A in Figure 25. Figure 35 is an enlarged schematic cross-sectional view of region XXXV enclosed by a dotted line in Figure 34. With reference to Figures 25, 34, and 35, in this embodiment, the lubricating oil is installed so that it is discharged vertically downward from one nozzle hole 37a. To achieve this, the discharge tube 32 and the nozzle hole 37a are positioned vertically below the center line L0. Note that in embodiment 5, the same arrangement as in this embodiment (nozzle hole 37a may be arranged vertically below the center line L0) may also be used.

[0200] In this embodiment, the land portion 37b in FIG. 35 is the right-hand surface of the nozzle member 37 in FIG. 34, where the discharge port of the nozzle hole 37a is formed. In FIG. 35, as in FIGS. 26 and 27, the angle θ1 between the center line L1 and the straight line L2 is greater than 0° and less than 90°. As an example, the angle θ1 in FIG. 35 is approximately 30°. Furthermore, the following holds true in FIG. 35: θ2 is the angle formed by the land portion 37b of the nozzle member 37 and the side surface 37c of the nozzle member 37 adjacent to the lubricating oil supply unit 20 side of the land portion 37b in a cross section along the axial direction. In this case, the angle θ2 is greater than 0° and less than (θ1 + 90)°. Furthermore, it is preferable that the side surface 37c has an inclination angle greater than 0° with respect to the straight line L2 (i.e., it is not parallel to the straight line L2).

[0201] 35, the side surface 37c faces the cage inner diameter surface 16b (facing vertically downward). However, the discharge port of the nozzle hole 37a is not formed on the side surface 37c. Therefore, the side surface 37c is not a land portion.

[0202] In Figure 35 as well, the intersection of center line L1 and straight line L2 is designated as P. Also in Figure 35, the intersection of land portion 37b (the outlet of nozzle hole 37a) and center line L1 is designated as Q. In this case, the interval h, which is the distance between intersection point P and intersection point Q in the radial direction (the up-and-down direction in Figure 35), is preferably 0.1 mm or more and 5 mm or less.

[0203] Fig. 36 is a schematic perspective view of a circular ring-shaped nozzle member in embodiment 6. Referring to Fig. 36, nozzle member 37 in embodiment 6 may also be circular, as in embodiment 5. Fig. 37 is an enlarged schematic perspective view of area C surrounded by a dotted line in Fig. 36. Referring to Fig. 37, nozzle member 37B2 may be a block-shaped nozzle member obtained by cutting out a portion of the circular ring-shaped nozzle member in Fig. 36.

[0204] Figure 38 is a perspective schematic diagram further enlarging the area on the arrow side of line segment XXXVIII-XXXVIII in Figure 37 compared to Figure 37. The annular nozzle member 37 in Figure 36 and the block-shaped nozzle member 37B2 in Figures 37 and 38, in which a portion of the nozzle member 37 is cut away, have the shapes shown in Figures 37 and 38. With particular reference to Figures 37 and 38, the nozzle members 37 and 37B2 have an outermost shaft surface 37OS on the axially outer side (outermost portion), i.e., on the side facing the lubricant supply unit 20. The nozzle members 37 and 37B2 have an innermost shaft surface 37IS on the axially inner side (innermost portion), i.e., on the axially opposite side from the lubricant supply unit 20 (toward the rolling elements 15).

[0205] At least a portion of outermost shaft surface 37OS of the present embodiment contacts housing main body 21 in a manner similar to that of outermost shaft surface 37OS of embodiment 5. Since the manner of contact is the same as that of embodiment 5, the description thereof will not be repeated.

[0206] The innermost shaft surface 37IS is formed radially outward (lower in FIG. 38 ) of the radially innermost surface 37IF (described later) on the surface facing the rolling elements 15 in the axial direction (facing the rolling elements 15). The innermost shaft surface 37IS is formed radially outward (lower in FIG. 38 ) of the land portion forming surface 37bb on the surface facing the rolling elements 15. For example, when viewed from a plane in the radial direction, the innermost shaft surface 37IS has a curved arc-like shape. The innermost shaft surface 37IS may be inclined so that the axial distance from the outermost shaft surface 37OS gradually increases from the outermost radial surface to the innermost radial surface. However, although not shown, the axial distance from the innermost shaft surface 37IS to the outermost shaft surface 37OS may be substantially constant from the outermost radial surface to the innermost radial surface. In this case, in FIG. 38 , the innermost shaft surface 37IS is substantially parallel to the outermost shaft surface 37OS.

[0207] In the cross section CR of FIG. 38 , a thin groove-like surface 37d and a side surface 37c are continuous from the radially innermost portion (the top in FIG. 38 ) of the innermost surface 37IS of the shaft. On the opposite side of each of these surfaces from the innermost surface 37IS, a surface is formed that faces radially outward while being slightly inclined toward the axially inner side (the rolling element 15 side). This surface is the land portion-forming surface 37bb. The land portion-forming surface 37bb is continuous and adjacent to the side surface 37c. Alternatively, the thin groove-like surface 37d may be absent, and the side surface 37c may be continuous directly from the radially innermost portion of the innermost surface 37IS of the shaft, and the land portion-forming surface 37bb may be continuous directly from the side surface 37c. The inclination angles of the surface 37d and the side surface 37c relative to the axial direction in the cross section CR may be arbitrary as long as the land portion 37b satisfies the requirements for a land portion. The surface 37d and the side surface 37c are bent toward each other in the cross section CR as shown in FIG. 38 . In this embodiment, as long as the center line L1 and the straight line L2 of the cage inner diameter surface 16b intersect, the land portion 37b does not have to be parallel to the cage inner diameter surface 16b. Normally, the land portion 37b is inclined with respect to the cage inner diameter surface 16b. As shown in Figure 35, the land portion 37b may be disposed vertically above the cage inner diameter surface 16b.

[0208] As shown on land portion 37b in Fig. 37 and in cross section CR in Fig. 38, nozzle hole 37a enters the nozzle member from outermost shaft surface 37OS and bends, for example, at an angle close to a right angle within the nozzle member. From the bent portion, nozzle hole 37a extends to reach land portion 37b.

[0209] The nozzle member 37, 37B2 has a radially outermost surface 37OF on the radially outer side (outermost portion). The nozzle member 37, 37B2 has a radially innermost surface 37IF on the radially inner side (innermost portion), i.e., on the radially opposite side of the radially outermost surface 37OF. The radially outermost surface 37OF extends in the axial direction to connect the axially outermost surface 37OS to the axially innermost surface 37IS. The radially innermost surface 37IF extends in the axial direction to connect the axially outermost surface 37OS to the land portion forming surface 37bb. The radially outermost surface 37OF and the radially innermost surface 37IF may be curved in an arc shape when viewed in a radial plan view. When viewed in a radial plan view, the radially innermost surface 37IF overlaps both the radially outermost surface 37OF and the land portion forming surface 37bb. Furthermore, the radially innermost surface 37IF overlaps with the side surface 37c in a plan view from the radial direction. The radially innermost surface 37IF has an area larger than that of the radially outermost surface 37OF and the land portion forming surface 37bb.

[0210] As shown in Figures 37 and 38, the planar shape of land portion 37b may be circular. Alternatively, referring to Figure 39, the planar shape of land portion 37b may be triangular. Alternatively, in this embodiment, similarly to Figure 33, the planar shape of land portion 37b may be a polygon with four or more vertices, such as a hexagon. Figure 39 is an enlarged perspective schematic diagram of a second example of region C surrounded by a dotted line in Figure 36. Figure 39 is similar to the first example in Figure 37 except for the planar shape of land portion 37b, and therefore its description will not be repeated here.

[0211] The shapes of the nozzle members 37, 37B1, and 37B2 in each embodiment may be changed as appropriate depending on the operating conditions, specifically, the rotational speed of the bearing device 10, the temperature during operation, and the vibration during operation.

[0212] <Operation and Effect> The bearing device 10 of this embodiment has the configuration shown in Figures 34 and 35. That is, the angle θ2 formed by the tip end surface (land portion 37b) of the nozzle member 37, 37B2 and the side surface 37c of the surface of the nozzle member 37, 37B2 adjacent to the lubricating oil supply unit 20 side of the land portion 37b in the axial cross section is greater than 0° and not more than (θ1 + 90)°.

[0213] For example, as shown in Figures 34 and 35, the nozzle member 37 is positioned vertically below the center line L0, and lubricating oil is discharged vertically downward from the nozzle hole 37a. Therefore, oil droplets 38 formed at the discharge port naturally fall due to gravity. Therefore, compared to the case where lubricating oil is discharged vertically downward from the nozzle hole 37a as shown in Figure 27, the supply of lubricating oil to the cage inner diameter surface 16b is easier. If the angle θ2 satisfies the above requirements, the oil droplets 38 are more likely to leave the land portion 37b. If the above requirements are satisfied, the angle between the side surface 37c and the cage inner diameter surface 16b widens the gap between them. Furthermore, the inclination due to the angle between the side surface 37c and the cage inner diameter surface 16b makes it easier for the oil droplets 38 to move downward (toward the cage inner diameter surface 16b). Therefore, this embodiment further enhances the effects of embodiment 5.

[0214] However, it is difficult to satisfy the above-mentioned condition for angle θ2 for a nozzle member 37 of any shape. Figure 40 is an enlarged schematic cross-sectional view showing a situation in which the nozzle member and the cage inner diameter surface may interfere with each other, as a comparative example to Figure 35. Referring to Figure 40, this example satisfies the above-mentioned condition for angle θ2, but there is a possibility that the nozzle member 37 may interfere with (collide with) the cage inner diameter surface 16b in the lower right part of the figure. Therefore, from the perspective of avoiding such problems, it is preferable to use nozzle members 37, 37B2 having the shape characteristics shown in Figures 37 and 38, for example.

[0215] Seventh Embodiment <Configuration of Mechanical Device> With reference to FIGS. 41 and 42, the configuration of a spindle for a machine tool, which is an example of a mechanical device to which the bearing devices according to the fifth and sixth embodiments are applied, will be described.

[0216] FIG. 41 is a schematic cross-sectional view of a mechanical device to which the bearing device shown in FIG. 25 is applied. FIG. 42 is a schematic cross-sectional view of the mechanical device shown in FIG. 41. FIG. 41 includes a schematic cross-sectional view of a portion taken along line XLI-XLI in FIG. 42. Referring to FIGS. 41 and 42, a machine tool spindle 50 serving as a mechanical device according to this embodiment mainly includes a rotating shaft 51, a spindle housing 52, an outer peripheral housing 53, and a bearing device 10 (see FIG. 25). The spindle housing 52 (housing) is disposed on the outer peripheral side of the rotating shaft 51 so as to surround the periphery of the rotating shaft 51. The outer peripheral housing 53 is disposed on the outer periphery of the spindle housing 52. The bearing device 10 rotatably supports the rotating shaft 51 relative to the spindle housing 52.

[0217] Two bearing devices are disposed on the outer periphery of the rotating shaft 51. The inner ring 14 and inner ring spacer 34 of the bearing device are fitted and fixed to the side surface of the rotating shaft 51. The outer ring 13 and outer ring spacer 33 of the bearing are fitted and fixed to the inner circumferential surface of the spindle housing 52. The bearing including the inner ring 14, outer ring 13, and rolling elements 15 (balls) disposed between the inner ring 14 and outer ring 13 is an angular contact ball bearing. A lubricating oil supply unit 20 is disposed between the inner ring spacer 34 and outer ring spacer 33, which are disposed adjacent to the bearings. Another spacer is fitted and fixed to the rotating shaft 51 and spindle housing 52 between the two bearings (on the side opposite to the side where the lubricating oil supply unit is disposed), and abuts against the inner ring 14 and outer ring 13.

[0218] In the region facing the control circuit 27 of the lubricating oil supply unit, a through hole is formed through the housing main body 21 (see FIG. 26 ), the outer ring spacer 33, the spindle housing 52, and the outer housing 53. A flat portion is provided on the surface of the outer housing 53 at the outer peripheral end of the through hole, and a pedestal 57 is disposed on the flat portion. An output board 56 is disposed on the pedestal 57. The output board 56 and the control circuit 27 of the lubricating oil supply unit 20 are electrically connected, for example, by a contact probe 54. The contact probe 54 is disposed inside the through hole. One end of the contact probe 54 contacts an electrode pad (not shown) of the control circuit 27, and the other end of the contact probe 54 is connected to the output board 56 by a conductive wire 55. The contact probe 54 may be connected and fixed to the output board 56 side. Furthermore, the output board 56 and the control circuit 27 may be connected by wire as described above, but may also be connected using other connection means (for example, optical communication means using a light-emitting element and a light-receiving element).

[0219] A cover member 58 is fixed to the base 57 so as to cover the output board 56 arranged on the base 57. A battery, which is a power source for driving the circuit of the output board 56, and a storage unit are arranged on the output board 56. The battery may be, for example, a coin battery or a button battery. A lithium battery is preferably used as the battery. A holder for securing such a battery is arranged on the surface of the output board 56. The storage unit may also include a holding unit (slot) for connecting and securing an external storage medium, for example, a card-type external storage medium, and the external storage medium removably secured to the holding unit. Any conventionally known storage medium, such as a memory card, may be used as the external storage medium.

[0220] The cover member 58 has a U-shaped elongated hole (a hole for arranging a fixing bolt) formed therein so that the cover member 58 can be removed from the base 57 simply by loosening the fixing bolt 59 that connects the cover member 58 to the base 57. The battery and external storage medium can be replaced with the cover member 58 removed from the base 57.

[0221] The output board 56, sealed by the base 57 and cover member 58, constitutes the main part of the voltage monitoring unit. The base 57 and cover member 58 can be provided with any waterproof structure to prevent the intrusion of coolant used during machining using the machine spindle. Examples of waterproof structures that can be used include packing, O-rings, caulking, and resin molding.

[0222] The machine tool spindle 50 described above includes a unit main body and a lubricating oil supply unit. The unit main body is connected to the bearing 11 (see FIG. 26) including the inner ring 14, outer ring 13, and rolling elements 15 as described above, and includes a control unit having a control circuit 27 (see FIG. 25). The lubricating oil supply unit includes an external output unit 70, which is a voltage monitoring unit connected to the control unit by a connection line (contact probe 54).

[0223] The unit main body includes a control unit, a power supply unit, a lubricant supply unit, and a lubricant storage unit (lubricant tank 30). The control unit includes a control circuit 27. The power supply unit includes a power generation unit 25 (see FIG. 25) and a power supply circuit 26 (see FIG. 25). The lubricant supply unit includes the power supply circuit 26, a drive circuit 28, and a pump 29. The control unit is connected to the power supply unit and the lubricant supply unit. The control unit controls the lubricant supply state in the lubricant supply unit and acquires data related to the lubricant supply state. Examples of this data include the timing of lubricant supply, the interval between lubricant supply, and data on the voltage (storage voltage) in the power supply circuit (specifically, the power storage unit) when the pump 29 is operated.

[0224] Any configuration can be adopted as the connection between the control circuit 27 of the control unit and the output board 56 of the external output unit 70. However, for example, the calculation unit (microcomputer) installed in the control circuit 27 and the calculation unit of the output board 56 may be connected by a connection wire. The calculation unit of the control circuit 27 is connected to a power source and a ground by wiring or the like. Furthermore, on the output board 56, the calculation unit is connected to a battery and a memory unit. A signal (a signal transmitted from the control circuit 27) indicating data such as voltage can be transmitted from the calculation unit to the memory unit.

[0225] With the above configuration, data related to the lubricant supply status transmitted from the control circuit 27 is stored in the memory unit of the output board 56. The timing for transmitting the data from the control circuit 27 to the output board 56 can be any timing. However, for example, the data may be transferred from the control circuit 27 to the output board 56 when the memory unit of the control circuit 27 (such as a memory element included in the calculation unit or a memory element provided in the control circuit 27 independently of the calculation unit) becomes full with the data. If the data includes data on the time change in the stored voltage of the power supply unit, the data can be saved in an external storage medium via the memory unit of the output board 56 and then imported into an external computer or the like using the external storage medium. In this way, the status of the lubricant supply unit (such as the power generation status and the operating status of the pump 29) can be checked on the external computer.

[0226] <Operation of Mechanical Device> A machine tool spindle 50, which is an example of a mechanical device shown in Figures 41 and 42, has a rotating shaft 51 connected to a predetermined drive shaft and rotatable relative to a spindle housing 52. In a bearing device that supports the rotating shaft 51, a lubricating oil supply unit periodically supplies lubricating oil to bearings 11 (see Figure 26). This improves the reliability and durability of the machine tool spindle 50.

[0227] The timing of oil supply to the bearing 11 by the lubricating oil supply unit 20 in the bearing device 10 is arbitrary. However, when the rotating shaft 51 rotates at high speed, a swirling air flow occurs around the rolling elements 15 as the bearing 11 rotates. This can cause the lubricating oil to spread, which can hinder smooth delivery of the lubricating oil. Therefore, from the perspective of avoiding such problems, it is preferable to oil the bearing 11 while the bearing 11 is stopped or when the bearing 11 is rotating at a rotational speed with a dn value of 200,000 or less.

[0228] <Operation and Effect> The mechanical device (machine tool spindle 50) according to the fifth and sixth embodiments includes a rotating shaft 51, a housing (spindle housing 52) disposed on the outer periphery of the rotating shaft 51, and the bearing device 10 that rotatably supports the rotating shaft 51 relative to the housing. This allows the bearing device 10 to operate stably for a long period of time, which in turn allows the mechanical device to operate stably for a long period of time.

[0229] Eighth Embodiment <Configuration of Bearing Device> Fig. 43 is a schematic side view of a bearing device according to this embodiment. Fig. 44 is a schematic cross-sectional view of a portion along line XLIV-XLIV in Fig. 43 in Embodiment 8. With reference to Figs. 43 and 44, bearing device 10 according to this embodiment is a rolling bearing device. Bearing device 10 includes bearing 11, which is a rolling bearing, and lubricant supply unit 20 (lubricant supply mechanism). Lubricant supply unit 20 supplies lubricant to bearing 11. A center line L0 passing through the center of bearing 11, which has an annular shape, extends in the left-right direction in Fig. 44, i.e., in the axial direction. Lubricant supply units 20 are arranged adjacent to each other in the axial direction of bearing 11, i.e., in the direction in which center line L0 extends.

[0230] An outer ring spacer 33 and an inner ring spacer 34 abut against one axial end of the bearing 11. The outer ring spacer 33 has an outer ring spacer outer ring 33A that is radially outer and an inner ring spacer inner ring 33B that is radially inner. The radial direction refers to the direction extending radially from the center of the annular bearing 11 toward the periphery, forming a diameter (radius). The lubricating oil supply unit 20 is incorporated inside the outer ring spacer 33, more specifically, between the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B. In this sense, the outer ring spacer 33 and the inner ring spacer 34 are not included in the lubricating oil supply unit 20. However, the lubricating oil supply unit 20 may also be considered to include the outer ring spacer 33 and the inner ring spacer 34. For example, the lubricating oil supply unit 20, the outer ring spacer 33, and the inner ring spacer 34 may be integrated into one unit.

[0231] The bearing device 10, which includes the bearing 11 and the lubricating oil supply unit 20, is used by being installed in a mechanical device, for example, between a rotating shaft and a spindle housing. When the bearing device 10 is installed in a mechanical device, for example, another spacer may be abutted against the other end of the bearing 11. In this case, the bearing 11 can be positioned in the axial direction by the outer ring spacer 33, inner ring spacer 34, and other spacers.

[0232] The bearing 11 mainly comprises an outer ring 13, an inner ring 14, multiple rolling elements 15, a cage 16, and a sealing member. The outer ring 13 is, for example, a fixed raceway. However, the outer ring 13 may also be a rotating raceway. The inner ring 14 is, for example, a rotating raceway. However, the inner ring 14 may also be a fixed raceway. The multiple rolling elements 15 are interposed between the inner ring 14 and the outer ring 13. The multiple rolling elements 15 are arranged on an annular track with spacing between them in the circumferential direction. The circumferential direction is the direction in which the circumference of the annular shape of the inner ring 14 extends. The cage 16 holds the multiple rolling elements 15 at regular intervals. The sealing member is located on the outer periphery of the cage 16. The bearing 11 may be, for example, an angular contact ball bearing, a deep groove ball bearing, or a cylindrical roller bearing. The bearing 11 is pre-filled with a desired grease. The sealing member is disposed at the end opposite to the side where the outer ring spacer 33 and the like are disposed.

[0233] The outer ring 13 of the bearing 11 has an outer ring rolling surface formed on its inner peripheral surface with which the rolling elements 15 come into contact. The inner ring 14 of the bearing 11 has an inner ring rolling surface formed on its outer peripheral surface with which the rolling elements 15 come into contact. The inner ring rolling surface faces the outer ring rolling surface. Therefore, the inner ring 14 is disposed radially inside the outer ring 13. The outer peripheral surface also includes an inclined portion 14a that continues to the inner ring rolling surface. The inclined portion 14a is inclined with respect to the axial direction so as to approach the outer ring 13 from the axial end of the inner ring 14 toward the inner ring rolling surface.

[0234] The cage 16 of the bearing 11 has a cage inner diameter surface 16b. The cage inner diameter surface 16b is the surface of the cage 16 that faces radially inward. The cage inner diameter surface 16b has a cross-sectional shape that increases in diameter from the end portion of the bearing 11 in the axial direction toward the center. The cage inner diameter surface 16b may be linear extending along the axial direction. In this way, in the cross section of the bearing 11 taken along the axial direction shown in Figure 44, the shape of the cage inner diameter surface 16b may be linear. However, the cage inner diameter surface 16b may also be curved and recessed toward the outer periphery of the bearing 11.

[0235] The spacer is made up of an outer ring spacer 33 and an inner ring spacer 34. In the axial direction, one end of the outer ring 13 contacts and is connected to the outer ring spacer 33. In the axial direction, one end of the inner ring 14 contacts and is connected to the inner ring spacer 34. Here, one end of the outer ring 13 (inner ring 14) means the end located on the left side of the bearing 11 in the axial direction. This brings the spacer into contact with the bearing 11. In addition, in the radial direction, a lubricating oil supply unit 20 is disposed between the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B. A discharge tube 32 extends from the lubricating oil supply unit 20 toward the bearing 11.

[0236] The outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B that make up the outer ring spacer 33 may both be formed from a metal material (iron). In this case, the interior of the outer ring spacer 33 may be partially hollowed out, with the lubricant supply unit 20 housed therein. In this case, too, the lubricant supply unit 20 is sandwiched (encased) between the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B, as shown in FIG. 44 . However, the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B may be made of different materials. For example, the outer ring spacer outer ring 33A may be made of iron, and the outer ring spacer inner ring 33B may be made of resin. There is a radial gap between the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B at least in the range shown in FIG. 44 , and the lubricant supply unit 20 is interposed in this gap. Regardless of whether the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B are made of the same material or not, the lubricant supply unit 20 may be disposed so as to be sandwiched radially between them as shown in Figure 44. Regardless of whether the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B are made of the same material or not, the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B are connected by an interposition portion 33C between them. This results in the outer ring spacer 33 being an integrated member made up of the outer ring spacer outer ring 33A, the outer ring spacer inner ring 33B, and the interposition portion 33C.

[0237] The outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B may be formed by turning, or the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B may be formed by pressing.

[0238] The lubricating oil supply unit 20 mainly includes a heat absorption / radiation section 25, a first power supply circuit 26A (power supply), a control circuit 27, a drive circuit 28, a pump 29, and a lubricating oil tank 30. These are arranged circumferentially on the radially inner side of the housing. Here, the housing refers to the outer diameter portion of the outer ring spacer 33, and more specifically, the outer ring spacer outer ring 33A. The first power supply circuit 26A (power supply), the control circuit 27, and the drive circuit 28 may be protected by a casing or a resin mold.

[0239] The first power supply circuit 26A may include a charging unit. The lubricating oil tank 30 (retention unit) stores (holds) the same type of lubricating oil as the base oil of the grease already sealed in the bearing 11. "Pre-sealed in the bearing 11" here means that the lubricating oil is already stored (held) in the bearing 11 before being supplied by the lubricating oil tank 30. The heat absorption and radiation unit 25, the first power supply circuit 26A, the control circuit 27, the drive circuit 28, the pump 29, and the lubricating oil tank 30 are arranged in a circumferential direction. The heat absorption and radiation unit 25 is connected to the first power supply circuit 26A. The first power supply circuit 26A is connected to the control circuit 27. The control circuit 27 is connected to the drive circuit 28. The drive circuit 28 is a circuit for operating a pump 29, such as a micropump. The drive circuit 28 is connected to the pump 29. These are electrically connected by wiring 35. The pump 29 is connected to a suction tube 31 connected to, for example, a bag body of a lubricating oil tank 30, and a discharge tube 32 (see Figure 44) for supplying lubricating oil from the pump 29 to the inside of the bearing 11.

[0240] 44, a nozzle 32a is connected to the tip of the discharge tube 32. The tip of the discharge tube 32 is the end of the discharge tube 32 opposite the base portion connected to the pump 29. A nozzle hole is formed inside the nozzle 32a.

[0241] The nozzle 32a is arranged to extend from the interior of the lubricant supply unit 20 inside the housing to the exterior of the lubricant supply unit 20. The tip of the nozzle 32a extends to the interior of the bearing 11. For example, the tip of the nozzle 32a may be arranged in the region between the cage inner diameter surface 16b and the inner ring rolling surface.

[0242] The heat absorption and radiation section 25 of the lubricating oil supply unit 20 may be, for example, a section that absorbs and releases heat using the Peltier effect. Specifically, the heat absorption and radiation section 25 includes a first thermal conductor 23a, a second thermal conductor 23b, and a Peltier element 24. The first thermal conductor 23a is connected to the outer ring 33A of the outer ring spacer. The second thermal conductor 23b is connected to the inner ring 33B of the outer ring spacer. The Peltier element 24 is disposed to connect the first thermal conductor 23a and the second thermal conductor 23b. In other words, the Peltier element 24 is disposed so as to be sandwiched between the first thermal conductor 23a and the second thermal conductor 23b. The Peltier element 24 is tightly fixed to the first thermal conductor 23a and the second thermal conductor 23b. The Peltier element 24 is a thermoelectric element that utilizes the Peltier effect.

[0243] The outer ring spacer inner ring 33B and the inner ring spacer 34 are not in contact with each other. A gap 36 may be formed between the outer ring spacer inner ring 33B and the inner ring spacer 34. Therefore, the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B are arranged to sandwich the entire heat absorption and radiation portion 25 in the radial direction.

[0244] The Peltier element 24 and the first power supply circuit 26A are electrically connected. Therefore, the first power supply circuit 26A (power supply) can supply power to the Peltier element 24. The first power supply circuit 26A may be an external power supply or a power storage circuit. In this case, power is stored in a power storage unit such as a battery or capacitor included in the first power supply circuit 26A. Alternatively, the first power supply circuit 26A may be composed of a generator and a power storage unit. In this case, the generator may be an electromagnetic induction generator, and the type is not important. The stored power can be supplied to the Peltier element 24. The first power supply circuit 26A may also be a battery. Furthermore, the first power supply circuit 26A may be a mechanism that supplies power to the Peltier element 24 via a wired or wireless connection from outside the rotating shaft of a machine tool spindle, as described below.

[0245] When the bearing device 10 is in use, power is supplied from the first power supply circuit 26A to the Peltier element 24. This drives the Peltier element 24. This enables heat to transfer from the first thermal conductor 23a, which is tightly secured to the Peltier element 24, to the second thermal conductor 23b. Specifically, when the Peltier element 24 is driven, heat is absorbed from the radially outer end face of the Peltier element 24 and dissipated to the radially inner end face of the Peltier element 24. As a result, the first thermal conductor 23a, which is tightly secured to the radially outer end face of the Peltier element 24, absorbs heat and cools. The second thermal conductor 23b, which is tightly secured to the radially inner end face of the Peltier element 24, dissipates heat and heats up.

[0246] Furthermore, by driving the Peltier element 24, the first thermal conductor 23a can absorb heat from the spacer (outer ring spacer 33), and the second thermal conductor 23b can radiate heat to the lubricating oil tank 30. To make this possible, a first thermal conductive member 23aa is connected to the first thermal conductor 23a, and a second thermal conductive member 23bb is connected to the second thermal conductor 23b.

[0247] The first heat conducting member 23aa and the second heat conducting member 23bb are made of a highly thermally conductive material, primarily composed of either copper or aluminum, and are formed into a long, thin plate shape. The first heat conducting member 23aa extends from the first heat conductor 23a in the circumferential direction along the inner circumferential surface of the outer ring spacer outer ring 33A.

[0248] The first heat conducting member 23aa contacts the spacer. The first heat conducting member 23aa may be connected to the first heat conductor 23a and extend in an arc from there to contact the inner circumferential surface of the outer ring spacer outer ring 33A. This positions the first heat conducting member 23aa radially outward from the lubricating oil tank 30. It is preferable that the first heat conducting member 23aa does not contact the outer circumferential surface of the lubricating oil tank 30 in the radial direction.

[0249] In Figures 43 to 47, the second heat conduction member 23bb contacts the lubricant oil tank 30. This includes cases where the second heat conduction member 23bb contacts a partial area of ​​the lubricant oil tank 30. The second heat conduction member 23bb may be connected to the second heat conductor 23b and extend in an arc from there so as to contact the inner outer wall of the lubricant oil tank 30 in the radial direction. The second heat conduction member 23bb may extend in an arc from the connection portion with the second heat conductor 23b so as to contact the outer peripheral surface of the outer ring spacer inner ring 33B. As a result, the second heat conduction member 23bb is disposed radially inward of the lubricant oil tank 30 (inner than the first heat conduction member 23aa). The lubricant oil tank 30 is disposed radially inward relative to the first power supply circuit 26A, the control circuit 27, and the drive circuit 28. The first power supply circuit 26A, the control circuit 27, and the drive circuit 28 are disposed radially outward relative to the lubricant oil tank 30. Therefore, the first power supply circuit 26A, the control circuit 27, and the drive circuit 28 may be in contact with the first heat conductive member 23aa or the inner circumferential surface of the outer ring spacer outer ring 33A.

[0250] As shown in Figure 43, the first heat conducting member 23aa may extend so as to contact only a portion of the circumferential surface of the outer ring spacer outer ring 33A. For example, the first heat conducting member 23aa may not contact the region radially outward of the drive circuit 28. In other words, the first heat conducting member 23aa may contact only the region in the circumferential direction other than the portion where the drive circuit 28 is located. However, the first heat conducting member 23aa may extend so as to contact the entire circumferential surface of the outer ring spacer outer ring 33A. Also, as shown in Figure 43, the second heat conducting member 23bb may be located only partially in the circumferential direction, that is, only in the region where the lubricating oil tank 30 is located (including the region adjacent to that).

[0251] As described above, the Peltier element 24, the first heat conductor 23a, the second heat conductor 23b, and the first power supply circuit 26A are all installed in the outer ring spacer 33. Specifically, they are installed in the area sandwiched between the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B. Usually, they are installed in a spacer connected to the fixed ring.

[0252] For example, in the case of a bearing device 10 for a machine tool, the rotating shaft that performs machining is on the inner ring side, so the inner ring is the rotating ring and the outer ring is the fixed ring. However, in a bearing device 10 used for other applications (for example, an automobile), the inner ring may be the fixed ring and the outer ring the rotating ring. In this case, the Peltier element 24, the first heat conductor 23a, the second heat conductor 23b, and the first power supply circuit 26A may all be installed in the inner ring spacer 34. In this case, the inner ring spacer 34 may include an inner ring spacer outer ring and an inner ring spacer inner ring, similar to the outer ring spacer 33 described above.

[0253] By placing the Peltier element 24 on a spacer connected to the fixed ring, it can be installed stably. However, it is also possible to install the Peltier element 24, the first thermal conductor 23a, the second thermal conductor 23b, and the first power supply circuit 26A on a spacer connected to the rotating ring. Specific application examples include when the rotation speed is low or when the rotating member rotates on a pivot.

[0254] The control circuit 27 is a control unit for controlling the operation of the pump 29 via the drive circuit 28. The control circuit 27 includes a program storage unit that stores a control program and a calculation unit (microcomputer) that is connected to the program storage unit and executes the control program. The control circuit 27 can be used to preset the start time of lubricating oil supply to the bearing 11, the supply timing (interval), the drive time of the pump 29 for supplying lubricating oil, the amount of lubricating oil to be supplied, and other settings. By maintaining an appropriate lubricating oil supply state in this manner, the lubrication life of the bearing device can be extended.

[0255] In addition, the control circuit 27 acquires data relating to the supply status of lubricating oil in the lubricating oil supply unit 20. The control circuit 27 is also capable of outputting the data to the outside of the control circuit 27 (for example, to an output board 56 (see FIG. 69) serving as a receiving unit). The control circuit 27 also controls the operation of the Peltier element 24.

[0256] The drive circuit 28 may include, for example, any sensors (bearing temperature sensor, bearing rotation sensor, lubricant remaining amount sensor, lubricant temperature sensor, etc.) Signals from these sensors may be input to a calculation unit (microcomputer) of the drive circuit 28, which may automatically control the pump 29 according to the temperature of the bearing 11 and its rotation status, thereby adjusting the amount of lubricant supplied.

[0257] The pump 29 is controlled by the control circuit 27 via a drive circuit 28. The pump 29 sucks the lubricating oil from a lubricating oil tank 30 through a suction tube 31, and supplies the sucked lubricating oil to the inside of the bearing 11 through a discharge tube 32 and a nozzle 32 a.

[0258] Next, FIG. 45 is a schematic cross-sectional view of the basic form of the portion taken along line A-A in FIG. 43 . FIG. 46 is a schematic cross-sectional view of a first modified example of the portion taken along line A-A in FIG. 43 . Referring to FIG. 45 , the lubricant tank 30 may be entirely composed of an outer frame 30a. In this case, the outer frame 30a may be made of a metal material or a resin material. The lubricant tank 30 may be arranged in an arc shape along an annular housing (outer ring spacer outer ring 33A). The lubricant 38 may be stored in the outer frame 30a. However, referring to FIG. 46 , the lubricant tank 30 may include an outer frame 30a and a bag body 30b. In this case, the lubricant 38 is stored in the bag body 30b.

[0259] The bag body 30b may be formed by stacking resin sheets and heat-welding the outer periphery thereof. The bag body 30b may be the portion to which the outer periphery of the lubricating oil tank 30 is heat-welded.

[0260] The bag body 30b is provided with a suction tube 31 that connects to the pump 29. When the bag body 30b of the lubricating oil tank 30 is formed by heat welding, the suction tube 31 is sandwiched between the resin sheets that are stacked to form the bag body 30b and heat-welded. In this way, the suction tube 31 can be integrated with the bag body 30b.

[0261] The bag 30b may be made of a resin material. Specifically, the bag 30b may be made of nylon, polyethylene, polyester, polypropylene, or the like. The bag 30b is made of any material that is flexible and can be deformed by a small external force, and is durable against the lubricating oil 38. The bag 30b can prevent the lubricating oil 38 from leaking from the outer frame 30a of the lubricating oil tank 30.

[0262] As shown in FIG. 45 , the second heat conducting member 23bb may be provided so as to contact the outer surface of the lubricating oil tank 30 on the radially inner side. Alternatively, as shown in FIG. 46 , a portion (a radially inner region) of the outer frame 30a of the lubricating oil tank 30 may be missing, and the second heat conducting member 23bb may be disposed in the missing portion. That is, in FIG. 46 , the second heat conducting member 23bb constitutes a portion of the outer frame 30a of the lubricating oil tank 30. As in FIG. 43 , the second heat conducting member 23bb also contacts the outer frame 30a of the lubricating oil tank 30 (the portion of the outer frame 30a other than the second heat conducting member 23bb). The second heat conducting member 23bb in FIG. 46 is integrated (integrated) with the outer frame 30a (the portion other than the second heat conducting member 23bb).

[0263] Figure 47 is a cross-sectional schematic diagram of a second modified example taken along line A-A in Figure 43. Referring to Figure 47, the second heat conducting member 23bb may be formed to constitute the entire outer frame 30a of the lubricating oil tank 30. In other words, the entire portion of the outer frame 30a of the lubricating oil tank 30 that surrounds and houses the lubricating oil 38 as shown in Figure 45 is formed by the second heat conducting member 23bb. The second heat conducting member 23bb in Figure 47 is integrated (integrated) with the second heat conducting member 23bb in Figure 43. The second heat conducting member 23bb is arranged as part of the outer frame 30a of the entire lubricating oil tank 30. As shown in Figure 47, a bag 30b may be housed within the outer frame 30a of the lubricating oil tank 30.

[0264] Although the cross section of the outer frame 30a of the lubricating oil tank 30 shown in Figures 45 to 47 is rectangular, the cross-sectional shape of the lubricating oil tank 30 is not limited to this.

[0265] <Operation of Bearing Device> In the bearing device 10 including the bearing 11 and the lubricating oil supply unit 20, the operation of the pump 29 is controlled by the control circuit 27. This allows lubricating oil to be supplied from the lubricating oil tank 30 to the bearing 11.

[0266] The lubricating oil supplied to the interior of the bearing 11 through the nozzle 32a is temporarily stored in the region between the cage inner diameter surface 16b and the inner ring rolling surface. The lubricating oil then flows from this region toward the rolling elements 15 due to centrifugal force caused by the rotation of the inner ring 14 and capillary action. In this way, the lubricating oil supplied to the interior of the bearing 11 is supplied to the contact areas between the rolling elements 15 and the inner ring 14 and outer ring 13. As a result, the lubricating performance of the bearing 11 can be maintained for a long period of time.

[0267] The pump 29 may be driven when the power generated by the heat absorption and radiation unit 25 is stored in a power storage unit (e.g., a capacitor) in the first power supply circuit 26A and the voltage of the power storage unit reaches a certain voltage. In this case, the pump 29 is driven by the power stored in the first power supply circuit 26A. Strictly speaking, the pump 29 is driven by the power stored in the first power supply circuit 26A being supplied to the control circuit 27. This is because the first power supply circuit 26A, the control circuit 27, the drive circuit 28, and the pump 29 are all connected in series. However, the pump 29 may also be driven by a power source other than the above, not shown.

[0268] <Operations and Effects> Next, operations and effects of the present embodiment will be described, while appropriately touching upon the background art, etc. Note that the description in this section may partially overlap with the description in the section on the configuration of the bearing device described above.

[0269] The bearing device of this embodiment includes a bearing 11 and a lubricant supply unit 20 that supplies lubricant to the bearing 11. The bearing 11 includes an outer ring 13 and an inner ring 14. The outer ring 13 has an outer ring rolling surface on its inner circumferential surface. The inner ring 14 has an inner ring rolling surface on its outer circumferential surface and is disposed inside the outer ring 13 so that the inner ring rolling surface faces the outer ring rolling surface. The lubricant supply unit 20 includes a holding portion (lubricant tank 30), a Peltier element 24, a first thermal conductor 23a, a second thermal conductor 23b, and a power source (first power supply circuit 26A). The lubricant tank 30 holds lubricant to be supplied to the interior of the bearing 11. The first thermal conductor 23a and the second thermal conductor 23b sandwich the Peltier element 24. The first power supply circuit 26A is capable of supplying power to the Peltier element 24. Driving the Peltier element 24 by the first power supply circuit 26A enables heat to be transferred from the first thermal conductor 23a to the second thermal conductor 23b.

[0270] The first power supply circuit 26A supplies power to the Peltier element 24 to drive it. The Peltier effect of the Peltier element 24 allows the first thermal conductor 23a, which is radially sandwiching the Peltier element 24, to function as a cool heat absorption member, and the second thermal conductor 23b to function as a hot heat dissipation member. Utilizing this, desired components within the bearing device 10 can be cooled and other desired components can be heated. Therefore, the desired cooling and heating can be achieved solely through the heat absorption and dissipation of the heat dissipation unit 25 by the first power supply circuit 26A, without unnecessary driving of the device for cooling or heating.

[0271] An example of a component within the bearing device 10 that needs to be cooled is the bearing 11. An example of a component within the bearing device 10 that needs to be heated is the lubricating oil tank 30. According to this embodiment, the lubricating oil 38 sealed in the lubricating oil tank 30 can be efficiently consumed while suppressing a temperature rise in the high-speed rotation bearing 11. The lubricating oil 38 can be efficiently consumed because the viscosity of the lubricating oil 38 sealed in the lubricating oil tank 30 decreases as the temperature rises, increasing its fluidity and making it easier to supply to the pump 29. Efficient consumption of the lubricating oil 38 means that a sufficient amount of lubricating oil 38 can be supplied to the desired position. This improves the lubrication durability of the bearing 11.

[0272] When the bearing device 10 rotates at high speeds, heat generated by the bearing 11 accelerates the deterioration of the lubricating oil. This can lead to a problem in which the lubrication durability of the bearing 11 cannot be ensured even at rotational speeds lower than the maximum usable rotational speed of the bearing 11. Meanwhile, the market demands even higher rotational speeds, that is, demands for improving the lubrication durability of the bearing 11 by supplying sufficient lubricating oil to the bearing 11 under high-speed rotation. According to this embodiment, heat transfer from the first thermal conductor 23a to the second thermal conductor 23b can prevent temperature rise in areas where heat generation is not desired. As a result, the lubrication durability of the bearing 11 can be improved even when the bearing 11 rotates at high speeds.

[0273] Air-oil lubrication is suitable for high-speed rotation. However, air-oil lubrication equipment is large and consumes a large amount of air-oil. For this reason, there are situations where using air-oil is not desirable, such as when it is desired to downsize the equipment. In such situations, the bearing device 10 of this embodiment is suitable. The bearing device 10 is compact and can easily supply a small amount of lubricating oil to the bearing 11 even under high-speed rotation, without using air-oil. Therefore, by consuming a small amount of lubricating oil highly efficiently, the lubrication durability of the bearing 11 can be maintained at a high level.

[0274] The bearing device 10 includes spacers (outer ring spacer 33, inner ring spacer 34) arranged to sandwich the lubricating oil supply unit 20. The outer ring spacer 33 (or inner ring spacer 34) contacts the bearing 11. When the Peltier element 24 is driven, the first heat conductor 23a can absorb heat from the outer ring spacer 33 (or inner ring spacer 34). When the Peltier element 24 is driven, the second heat conductor 23b can radiate heat to the lubricating oil tank 30.

[0275] The first thermal conductor 23a absorbs heat from the spacer, allowing the first thermal conductor 23a to absorb heat from the bearing 11. This is because the spacer is in contact with the bearing 11. This makes it possible to suppress heat generation in the bearing 11 and the associated early depletion of lubricating oil in the bearing 11. As a result, damage to the bearing 11 can be suppressed. The control circuit 27 may also be installed adjacent to the cool first thermal conductor 23a. In this way, it is possible to suppress the heat generated by the bearing 11 due to driving from being transmitted to the control circuit 27. This prevents the board that constitutes the control circuit 27 from being affected by heat.

[0276] The second heat conductor 23b heats the lubricating oil tank 30. That is, as shown in Figures 45 and 46, heat H is supplied from the second heat conductive member 23bb to the lubricating oil 38 inside the lubricating oil tank 30. This heats the lubricating oil 38, improving the fluidity of the lubricating oil 38 and making it easier to discharge the lubricating oil from the nozzle. This allows the lubricating oil to be sufficiently supplied into the bearing 11. In other words, malfunctions of the bearing 11 caused by an insufficient supply of lubricating oil to the bearing 11 can be suppressed.

[0277] In the above-described bearing device 10, a first heat conducting member 23aa is connected to the first heat conductor 23a, and a second heat conducting member 23bb is connected to the second heat conductor 23b. It is more preferable that the first heat conducting member 23aa contacts the outer ring spacer 33 (inner ring spacer 34), and the second heat conducting member 23bb contacts the lubricating oil tank 30.

[0278] The first heat conductor 23a can absorb heat from the spacer through the first heat conduction member 23aa connected thereto. For example, if the first heat conduction member 23aa contacts the inner circumferential surface of the outer ring spacer outer ring 33A, the outer ring spacer outer ring 33A is actively cooled. This suppresses temperature rise due to heat generated by the bearing 11 in contact with the spacer. If the control circuit 27 or the first heat conduction member 23aa comes into contact with the outer ring spacer outer ring 33A or the first heat conduction member 23aa, the control circuit 27 and other components can be protected from heat. The second heat conductor 23b can dissipate heat to the lubricating oil tank 30 through the second heat conduction member 23bb connected thereto (see heat H in Figures 45 and 46). For example, if the second heat conduction member 23bb extends in an arc shape so as to contact the lubricating oil tank 30, the lubricating oil tank 30 and the lubricating oil therein can be warmed. The second heat conducting member 23bb may come into contact with the outer peripheral surface of the outer ring spacer inner ring 33B, thereby actively heating the outer ring spacer inner ring 33B.

[0279] The first heat conducting member 23aa actively cools the outer ring spacer outer ring 33A, and the second heat conducting member 23bb actively heats the outer ring spacer inner ring 33B. This effect is achieved by using either copper or aluminum as the main component of the first heat conducting member 23aa and the second heat conducting member 23bb. This is because copper and aluminum have high thermal conductivity.

[0280] The outer ring spacer outer ring 33A, which is actively cooled, and the outer ring spacer inner ring 33B, which is actively heated, are the same component (outer ring spacer 33). In other words, the outer ring 33A and inner ring 33B of the outer ring spacer are integral. The outer ring 33A and inner ring 33B may be made of the same material. For this reason, by cooling and heating as described above, the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B may become approximately the same temperature. However, even if this occurs, there is no particular problem as long as the bearing 11 is not excessively heated and the lubricating oil 38 has a viscosity that allows it to flow sufficiently, and the object of this embodiment can be achieved.

[0281] In the above-described bearing device 10, the bearing 11 is pre-filled with lubricating oil. The lubricating oil is grease. This allows for applications where air-oil lubrication is undesirable. For example, grease lubrication is increasingly being used instead of air-oil lubrication for machine tool spindle bearings. This is intended to reduce environmental impact and costs. Grease lubrication eliminates the need for the lubricating oil tank and lubricating oil supply device used in air-oil lubrication. The lubricating oil tank used in air-oil lubrication is large, and the lubricating oil supply device is a complex device with a pump that has a forced discharge function. Therefore, grease lubrication allows for a more compact facility compared to air-oil lubrication. Furthermore, grease lubrication uses less lubricating oil than air-oil lubrication. Therefore, grease lubrication is environmentally friendly and reduces initial and running costs.

[0282] In the case of a grease-lubricated bearing, application of this embodiment facilitates the separation of grease adhering to the cage bore surface 16b. In other words, capillary action actively acts on the liquid lubricating oil adhering to the cage bore surface 16b. This allows the liquid lubricating oil to sufficiently reach the rolling surfaces inside the bearing 11 when the grease is depleted, i.e., when there is little grease.

[0283] Ninth Embodiment In the following embodiments, the same configurations, features, materials, etc. as those in the eighth embodiment will not be described repeatedly unless it is preferable to do so again.

[0284] <Configuration of bearing device> Fig. 48 is a schematic side view of a bearing device according to embodiment 9. Referring to Fig. 48, in bearing device 10 according to this embodiment, movable piece 23cc is connected to either second heat conductor 23b or second heat conduction member 23bb. Movable piece 23cc is formed in the shape of an elongated plate, similar to first heat conduction member 23aa and second heat conduction member 23bb. In this respect, embodiment 9 differs from embodiment 8.

[0285] In Figure 48, similar to Figure 46, the second heat conducting member 23bb forms part of the outer frame 30a of the lubricating oil tank 30 and is integrated with the lubricating oil tank 30. In other words, the second heat conducting member 23bb contacts the lubricating oil tank 30 (portions other than the second heat conducting member 23bb). However, in this embodiment as well, the entire outer frame 30a may be made of a single member, as shown in Figure 45, with the second heat conducting member 23bb provided on its outside. The movable piece 23cc is connected to either the second heat conductor 23b or the second heat conducting member 23bb. When the movable piece 23cc is included, the lubricating oil tank 30 has a bag body 30b as shown in Figure 46.

[0286] The movable piece 23cc is made of a bimetal. In particular, the movable piece 23cc is preferably formed by bonding two types of metal materials, a low-expansion material and a high-expansion material. The low-expansion material is, for example, a Ni-Fe alloy. The high-expansion material is, for example, any one selected from the group consisting of copper, nickel, a Ni-Cu alloy, a Cu-Zn alloy, a Ni-Mn-Fe alloy, a Ni-Cr-Fe alloy, a Ni-Cu-Mn alloy, and a Ni-Mo-Fe alloy.

[0287] The movable piece 23cc is in contact with a partial area of ​​the lubricating oil tank 30. In Fig. 48, one end of the movable piece 23cc (the end opposite to the side connected to the second thermal conductor 23b) is in contact with a wall surface inside the lubricating oil tank 30. The movable piece 23cc preferably contacts a radially outer wall surface of the bag body 30b of the lubricating oil tank 30. The movable piece 23cc is connected to at least one (one or both) of the heat absorption and radiation portion 25 and the portion where the second heat conduction member 23bb is in contact with the heat absorption and radiation portion 25.

[0288] Figure 49 is a schematic perspective view showing the initial state of a first example of the lubricating oil tank shown in Figure 48 in a simplified form compared to Figure 48. Figure 50 is a schematic cross-sectional view of a portion taken along line L-L in Figure 49. Figure 51 is a schematic perspective view showing a state in which the bimetal has deformed compared to Figure 49. Figure 52 is a schematic cross-sectional view of a portion taken along line LII-LII in Figure 51. Figures 50 and 52 not only show the portion cut along line L-L, etc., but also the cross-sectional state of the portion behind that portion that is not actually visible because the lubricating oil tank 30 is curved.

[0289] 49 , the movable piece 23cc is usually installed inside the outer frame 30a of the lubricating oil tank 30. When the lubricating oil tank 30 has a bag body 30b, the movable piece 23cc is arranged outside the bag body 30b. However, the movable piece 23cc may also be arranged inside the bag body 30b. Whether the movable piece 23cc is arranged outside or inside the bag body 30b, the movable piece 23cc can come into contact with (is in contact with) the wall surface of the bag body 30b.

[0290] In the first example, in the initial state, the movable piece 23cc is connected to a region of the second heat conducting member 23bb adjacent to the portion that connects to the second heat conductor 23b. A gap is formed between the movable piece 23cc and the second heat conducting member 23bb in the radial direction. The bag 30b is disposed in this gap. Referring to Figure 50, in this state, the liquid level of the lubricating oil 38 stored inside the bag 30b is relatively low.

[0291] Referring to FIG. 51 , consider a state in which the movable piece 23cc has deformed and contracted relative to the initial state shown in FIG. 49 . The deformation of the movable piece 23cc is caused by the temperature rise of the lubricating oil tank 30 due to the second thermal conductor 23b and the second thermal conductive member 23bb, as shown in the eighth embodiment. Because the movable piece 23cc is in contact with the lubricating oil tank 30, the temperature rise of the lubricating oil tank 30 also causes the movable piece 23cc to heat up and deform. Referring to FIG. 52 , the movable piece 23cc moves in the direction indicated by arrow M. That is, the movable piece 23cc deforms so that the diameter of the arc-shaped extending portion becomes smaller. In this way, in accordance with the displacement of the movable piece 23cc indicated by arrow M, the movable piece 23cc presses against the bag body 30b, thereby deforming so that the volume of the bag body 30b becomes smaller. As a result, the liquid level of the lubricating oil 38 is higher in FIG. 52 than in FIG. 50 .

[0292] Figure 53 is a schematic perspective view showing the initial state of a second example of the lubricating oil tank shown in Figure 48, which is simplified from Figure 48. Figure 54 is a schematic cross-sectional view of a portion taken along line LIV-LIV in Figure 53. Figure 55 is a schematic perspective view showing a state in which the bimetal has deformed compared to Figure 53. Figure 56 is a schematic cross-sectional view of a portion taken along line LVI-LVI in Figure 55. As with Figures 50 and 52, Figures 54 and 56 not only show the portion cut along line LIV-LIV, etc., but also show the cross-sectional view of the portion behind that portion that is not actually visible because the lubricating oil tank 30 is curved.

[0293] Referring to FIG. 53 , the initial state of the second example is generally similar to that of the first example. However, FIG. 53 differs from FIG. 49 in the following respects. In FIG. 53 , the lubricating oil tank 30 is positioned such that the radially outer side is positioned vertically higher than the inner side. That is, in FIG. 53 , if the two are at the same horizontal coordinate position, the movable piece 23cc is positioned vertically higher than the second heat conduction member 23bb. Therefore, the lubricating oil tank 30 is tilted overall so that the movable piece 23cc is positioned higher than the second heat conduction member 23bb. This is shown in FIG. 53 as the movable piece 23cc extending radially outward from the portion connecting with the second heat conduction member 23bb, and then, when it reaches the inner circumferential surface of the lubricating oil tank 30, it is bent in an arc shape extending along the inner circumferential surface. The movable piece 23cc is positioned inside the outer frame 30a (not clearly shown in FIG. 53 ) of the lubricating oil tank 30. Movable piece 23cc is in contact with bag body 30b. In this respect, the configuration of Figure 53 differs from that of Figure 49, in which movable piece 23cc is not inclined upward in the vertical direction relative to second heat conduction member 23bb.

[0294] However, Figures 54 to 56 are similar to Figures 50 to 52. In the second example, too, rising temperature causes the movable piece 23cc to deform so that the diameter of the arc-shaped extending portion, as indicated by arrow M, becomes smaller. In response to this displacement of the movable piece 23cc, the bag body 30b is pressed and deformed, raising the liquid level of the lubricating oil 38. In the second example, the cross-sectional shape of the bag body 30b in the cross-sectional views of Figures 54 and 56 is tilted compared to Figures 50 and 52. Specifically, the lower right side of the figure, where the suction tube 31 is located, is tilted further downward. This tilt allows for a higher liquid level relative to the suction tube 31, as shown in Figure 56, even with an even smaller amount of lubricating oil 38 than in the first example.

[0295] <Operation and Effect> In the bearing device 10 of this embodiment, the retaining portion (lubricating oil tank 30) includes a resin bag body 30b. A movable piece 23cc is connected to either the second heat conductor 23b or the second heat conduction member 23bb. The movable piece 23cc is formed of a bimetal. The movable piece 23cc is in contact with the lubricating oil tank 30, and is able to press against the bag body 30b in accordance with the displacement of the movable piece 23cc, thereby changing the volume of the bag body 30b.

[0296] As shown in Figures 52 and 56, the reduction in the volume of the bag body 30b causes the liquid level of the lubricating oil 38 inside it to rise and become higher than the suction tube 31. In this way, even if the amount of lubricating oil 38 is small, the lubricating oil in the lubricating oil tank 30 can be sucked through the suction tube 31 and supplied to the inside of the bearing 11. Even when the amount of lubricating oil 38 is so small that it does not reach the suction tube 31, as shown in Figures 50 and 54, the liquid level reaches the height of the suction tube 31, as shown in Figures 52 and 56. This improves the fluidity of the lubricating oil 38 even with a small amount of lubricating oil 38. As a result, the lubricating oil 38 can be efficiently supplied from the suction tube 31 to the bearing 11 via the nozzle 32a (see Figure 44). This ensures the lubrication durability of the bearing 11 and allows the lubricating oil 38 to be consumed efficiently. Furthermore, the movable piece 23cc applies pressure to the bag body 30b from the outside, thereby increasing the discharge pressure of the lubricating oil 38 from the pump 29 (see Figure 48).

[0297] The same effect can be achieved whether the embodiment shown in FIG. 52 or the embodiment shown in FIG. 56 is used. In other words, the same effect can be achieved regardless of the shape of the component that stores the lubricating oil 38, such as the bag 30b. For this reason, as a third example (not shown), an example is conceivable in which the bag 30b is not provided, and the main body of the lubricating oil tank 30 (corresponding to the outer frame 30a) is formed of a flexible resin material, as shown in FIG. 45 . In this case, the movable piece 23cc may be installed on the outside of the main body of the lubricating oil tank 30 (corresponding to the outer frame 30a). In the third example, as in the first and second examples, the movable piece 23cc formed from a bimetal is connected to either the second thermal conductor 23b or the second thermal conduction member 23bb. This movable piece 23cc contacts the outside of the resin lubricating oil tank 30, and its displacement can change the volume of the resin lubricating oil tank 30. This also achieves the same effect as described above. However, the third example differs from the second example in that the lubricating oil tank 30 does not have two layers of a bag body and an outer frame thereof, but has only one layer of a bag body made of a resin material.

[0298] Tenth Embodiment <Configuration of Bearing Device> FIG. 57 is a schematic side view of a bearing device according to a tenth embodiment. Referring to FIG. 57 , in this embodiment, the first thermal conductor 23a is connected to the outer ring spacer inner ring 33B. In this embodiment, the second thermal conductor 23b is connected to the outer ring spacer outer ring 33A. That is, in this embodiment, the positions of the first thermal conductor 23a and the second thermal conductor 23b in FIG. 43 are reversed. Note that in this embodiment, the first thermal conductor 23a is connected to the first thermal conductor 23a, and the second thermal conductor 23bb is connected to the second thermal conductor 23b. Therefore, in this embodiment, the positions of the first thermal conductor 23aa and the second thermal conductor 23bb in FIG. 43 are reversed. In this embodiment, the second thermal conductor 23bb extends in an arc shape so as to contact the inner circumferential surface of the outer ring spacer outer ring 33A. The first heat conducting member 23aa extends in an arc shape so as to contact the outer peripheral surface of the inner ring of the outer ring spacer 33B, whereby the second heat conducting member 23bb is disposed radially outward of the lubricating oil tank 30 (outward of the first heat conducting member 23aa).

[0299] The lubricating oil tank 30 is disposed radially outward of the first power supply circuit 26A, the control circuit 27, and the drive circuit 28. The first power supply circuit 26A, the control circuit 27, and the drive circuit 28 are disposed radially inward of the lubricating oil tank 30. Therefore, the first power supply circuit 26A, the control circuit 27, and the drive circuit 28 may be in contact with the first heat conduction member 23aa or with the outer peripheral surface of the outer ring spacer inner ring 33B.

[0300] In Figure 57, movable piece 23cc is installed as shown in the following Figures 58 and 59, but movable piece 23cc is omitted in Figure 57. Figure 58 is a schematic perspective view showing the initial state of the lubricating oil tank in embodiment 10, similar to Figure 49. Figure 59 is a schematic perspective view showing a state in which the bimetal has deformed compared to Figure 58. Referring to Figures 58 and 59, in this embodiment as well, second heat conduction member 23bb is part of outer frame 30a of lubricating oil tank 30 and is integrated with lubricating oil tank 30. Second heat conduction member 23bb contacts lubricating oil tank 30 (portions other than second heat conduction member 23bb).

[0301] In this embodiment as well, movable piece 23cc is connected to either second thermal conductor 23b or second thermal conduction member 23bb. Therefore, in Figures 58 and 59, movable piece 23cc is in contact with the part of second thermal conduction member 23bb at the bottom of the figure, and extends from there toward the top of the figure.

[0302] It is preferable that the movable piece 23cc contacts the radially outer wall surface of the bag 30b of the lubricating oil tank 30. In this embodiment, the second heat conductor 23b and the second heat conduction member 23bb, which are heated, are arranged radially outward of the first heat conductor 23a and the first heat conduction member 23aa, which are heat absorbed. This allows the bag 30b to be smoothly pressed by the displacement of the movable piece 23cc. This is because the movable piece 23cc is arranged on the same radial side of the lubricating oil tank 30 as the second heat conduction member 23bb.

[0303] Although not shown in the figure, as another example, the movable piece 23cc connected to the second heat conduction member 23bb that contacts the outer ring spacer inner ring 33B, as in embodiment 8, may contact the radially inner wall surface of the bag body 30b of the lubricating oil tank 30.

[0304] As yet another example (not shown), the bearing device 10 of Fig. 57 may be configured without the heat absorption and dissipation section 25, but with a movable piece 23cc that comes into contact with the radially outer or inner wall surface of the bag body 30b of the lubricating oil tank 30. In this case as well, if the volume of the bag body 30b changes due to the displacement of the movable piece 23cc, an effect such as raising the liquid level of the lubricating oil 38 stored therein can be obtained.

[0305] (Embodiment 11) <Configuration of bearing device> Fig. 60 is a schematic side view of a bearing device according to embodiment 11. Referring to Fig. 60, in the bearing device 10 according to this embodiment, the lubricating oil supply unit 20 includes a storage circuit capable of storing electricity. Specifically, the first power supply circuit 26A has a first storage circuit 17A. The first storage circuit 17A has the following features. For this reason, the first storage circuit 17A of this embodiment is separate from the storage circuit and storage unit of the first power supply circuit 26A described in embodiment 8.

[0306] In the bearing device 10 of this embodiment, the operation of the Peltier element 24 changes depending on the state. That is, while the bearing device 10 is being driven, the Peltier element 24 can be in two states: a first state and a second state. Specifically, in the first state, the Peltier element 24 operates as a generator, and the power generated by the Peltier element 24 is stored in the first power storage circuit 17A.

[0307] During use, the temperatures of the inner ring 14 and the outer ring 13 rise due to frictional heat with the rolling elements 15. The outer ring 13 is usually incorporated into a spindle housing of a device, etc. Therefore, the outer ring 13 dissipates heat through thermal conduction. This causes a temperature difference between the inner ring 14 and the outer ring 13. The temperature of the inner ring 14 is higher than that of the outer ring 13. The temperature of the outer ring 13 is conducted to the first thermal conductor 23a, and the temperature of the inner ring 14 is conducted to the second thermal conductor 23b. This causes a temperature difference between the first and second thermal conductors 23a and 23b. As a result, in the first state, a temperature difference occurs between the two end faces of the Peltier element 24, which is disposed between the first and second thermal conductors 23a and 23b. This allows the Peltier element 24 to generate electricity through the Seebeck effect. In this embodiment, similarly to the eighth embodiment, the first heat conductor 23a is connected to the outer ring spacer 33A, and the second heat conductor 23b is connected to the outer ring spacer 33B. The outer ring spacer 33A absorbs heat, and the outer ring spacer 33B dissipates heat.

[0308] In this embodiment, the second thermal conductor 23b is also installed on the outer ring spacer 33, just like the first thermal conductor 23a. However, the second thermal conductor 23b is located radially inward of the first thermal conductor, i.e., closer to the inner ring 14. For this reason, the temperature of the second thermal conductor 23b is higher than that of the first thermal conductor 23a.

[0309] In the first state, the bearing device 10 rotates at a medium or low speed. In the first state, the electric power stored in the first power storage circuit 17A is used, for example, to drive the pump 29. The electric power may also be used to drive the control circuit 27 and the drive circuit 28.

[0310] In the second state, the bearing device 10 rotates at a higher speed than in the first state. In the second state, the power stored in the first power storage circuit 17A is supplied to the Peltier element 24. This causes heat to be transferred from the first thermal conductor 23a to the second thermal conductor 23b. In the second state, the Peltier element 24 and the heat absorption and dissipation unit 25 including it operate by the Peltier effect in the same manner as in the eighth embodiment, and therefore the description thereof will not be repeated.

[0311] The control circuit 27 switches the operation of the Peltier element 24 between a first state in which the rotating wheel is at a low or medium speed and a second state in which the rotating wheel is at a high speed when the detected value of the temperature sensor or bearing rotation sensor of the drive circuit 28 exceeds or falls below an arbitrarily set threshold value.

[0312] <Operation and Effect> In the bearing device 10 of this embodiment, the lubricating oil supply unit 20 further includes a storage circuit (first storage circuit 17A) that can store electricity. The Peltier element 24 is switchable between a first state and a second state. In the first state, the Peltier element 24 operates as a generator, and electricity is stored in the first storage circuit 17A. In the second state, the electricity stored in the first storage circuit 17A is supplied to the Peltier element 24A, and heat is transferred from the first thermal conductor 23a to the second thermal conductor 23b.

[0313] Damage caused by heat generated by bearing 11 is a concern primarily when bearing device 10 rotates at high speeds. This is because the amount of heat generated during high-speed rotation is large. For this reason, when a rotating shaft for a machine tool, for example, attached to bearing device 10 rotates at medium or lower speeds, Peltier element 24 operates as a generator in the first state, storing electricity in first power storage circuit 17A. Then, in the second state when the rotating shaft switches to high-speed rotation, the power stored in first power storage circuit 17A in the first state is used by heat absorption and radiation unit 25, including Peltier element 24, to absorb and dissipate heat. This configuration achieves the same effects as embodiment 8 and the like, while further improving the power consumption efficiency of bearing device 10.

[0314] (Embodiment 12) <Configuration of bearing device> Fig. 61 is a schematic side view of a bearing device according to embodiment 12. Referring to Fig. 61, in bearing device 10 according to the present embodiment, lubricating oil supply unit 20 has two Peltier elements. The two Peltier elements are Peltier element 24a and another Peltier element 24b.

[0315] The lubricant supply unit 20 includes a heat absorption / radiation section 25A and a power generation section 25B. The heat absorption / radiation section 25A has a first thermal conductor 23a1, a second thermal conductor 23b1, and a Peltier element 24a. The power generation section 25B has a first thermal conductor 23a2, a second thermal conductor 23b2, and another Peltier element 24b. The first thermal conductor 23a1 and the first thermal conductor 23a2 are connected to an outer ring 33A of an outer ring spacer. The second thermal conductor 23b1 and the second thermal conductor 23b2 are connected to an inner ring 33B of an outer ring spacer. The Peltier element 24a is sandwiched between the first thermal conductor 23a1 and the second thermal conductor 23b1 and fixed in close contact therewith. The other Peltier element 24b is sandwiched between the first thermal conductor 23a2 and the second thermal conductor 23b2 and fixed in close contact therewith.

[0316] The lubricant supply unit 20 includes a first power supply circuit 26A. The first power supply circuit 26A has a first storage circuit 17A. The control circuit 27 has a first control circuit 27A and a second control circuit 27B. The first control circuit 27A and the second control circuit 27B may be integrated, but do not have to be integrated. The second storage circuit 17B (another storage circuit) may be included in the second power supply circuit 26B.

[0317] As shown in FIG. 61 , the heat absorption and dissipation unit 25A, first power supply circuit 26A (first power storage circuit 17A), first control circuit 27A, second control circuit 27B, drive circuit 28, power generation unit 25B, second power storage circuit 17B (second power supply circuit 26B), pump 29, and lubricating oil tank 30 are arranged in this order circumferentially on the radially inner side of the housing. The heat absorption and dissipation unit 25A is connected to the first power supply circuit 26A. The first power supply circuit 26A is connected to the first control circuit 27A. The first control circuit 27A is connected to the drive circuit 28. These are connected to each other by first wiring 35A. Meanwhile, the second control circuit 27B is connected to the power generation unit 25B. The power generation unit 25B is connected to the second power storage circuit 17B. The second power storage circuit 17B is connected to the pump 29. These are connected to each other by second wiring 35B. The arrangement of the suction tube 31 and discharge tube 32 from the pump 29 is similar to that of the other embodiments.

[0318] The operation of the heat absorption and dissipation unit 25A and the first power supply circuit 26A is the same as in the eighth embodiment. That is, the first power supply circuit 26A (first power storage circuit 17A) supplies power to the Peltier element 24a, thereby driving the Peltier element 24a. This allows heat to be transferred from the first thermal conductor 23a1, which is tightly secured to the Peltier element 24a, to the second thermal conductor 23b1. The Peltier element 24a absorbs and dissipates heat due to the Peltier effect. As a result, the first thermal conduction member 23aa absorbs heat, and the second thermal conduction member 23bb dissipates heat.

[0319] Meanwhile, the operation of the power generation unit 25B and the second power storage circuit 17B is as follows. During operation, a temperature difference between the inner ring 14 and the outer ring 13 causes a temperature difference between the first thermal conductor 23a2 on the outer ring side of the adjacent lubricating oil supply unit 20 and the second thermal conductor 23b2 on the inner ring side. This causes a temperature difference between the two end faces of the other Peltier element 24b disposed between them. The other Peltier element 24b can utilize this temperature difference to generate electricity through the Seebeck effect. The power obtained by the power generation by the other Peltier element 24b is supplied to the second power supply circuit 26B connected thereto. As a result, power is supplied to and stored in the second power storage circuit 17B. The power stored in the second power storage circuit 17B is used to drive the pump 29.

[0320] The pump 29 is driven after a preset time has elapsed from the point in time when the voltage of the second power storage circuit 17B reaches the drive voltage of the pump 29. Next, drive control of the pump 29 will be described with reference to Figs. 62 to 65.

[0321] FIG. 62 is a graph showing a first example of the voltage of another storage circuit over time. The horizontal axis of the graph represents elapsed time, and the vertical axis represents the voltage of the second storage circuit 17B. This also applies to the following FIGS. 63 to 65. Referring to FIG. 62, the initial voltage of the second storage circuit 17B before charging (time T=0) is V0. The voltage when the second storage circuit 17B is fully charged is V1. The voltage V1 is the voltage for driving the pump 29. This voltage increases from V0 to V1 over time t1 as the second storage circuit 17B is charged. As shown in FIG. 62, even after the fully charged voltage V1 is reached, a predetermined period of time is designated as the charging time (delay time). In other words, from time t1 to time t2, the voltage of the second storage circuit 17B is maintained at the pump driving voltage V1. After the charging time has elapsed, the second storage circuit 17B is discharged at time t2, and the voltage drops to V0. Thereafter, the cycle of increasing the voltage (i.e., charging), maintaining the voltage, and decreasing the voltage (i.e., discharging) is repeated at a constant cycle t2. At each timing when the voltage decreases from V1 to V0, such as at times t2 and 3t2, the pump 29 is driven to supply lubricating oil to the bearing 11. The drive of the pump may be controlled in this manner.

[0322] Fig. 63 is a graph showing a second example of the voltage of another storage circuit over time. Referring to Fig. 63, second storage circuit 17B is charged from time T=0, and at time t3 when its voltage first rises to drive voltage V1 of pump 29, only discharging is performed, causing the drive voltage to drop to V0. At this point, pump 29 is not driven, and lubricating oil is not supplied to bearing 11. However, the rise in voltage, i.e., charging, and the fall in voltage, i.e., discharging, are repeated. For example, at time 4t3 when the fourth discharge occurs, pump 29 is driven for the first time, and lubricating oil is supplied to bearing 11. The drive of the pump may be controlled in this manner.

[0323] Fig. 64 is a graph showing a third example of the voltage of another storage circuit over time. Referring to Fig. 64, in the third example, as in the second example, the second storage circuit 17B is charged from time T = 0, and then charging and discharging are repeated. However, in the third example, the time for which the second storage circuit 17B is charged is t4, which is longer than t3 in the second example. For example, at time 3t4, when the third discharge occurs, the pump 29 is driven for the first time, and lubricating oil is supplied to the bearing 11 side. Control may be performed in this manner.

[0324] FIG. 65 is a graph showing a fourth example of the voltage of another storage circuit over time. Referring to FIG. 65, in the fourth example, similar to the first example, charging, maintaining the voltage, and discharging are performed for the second storage circuit 17B. Charging is performed over a period of time t5 from time T=0, and the first discharge occurs at time t6. However, the time (t6-t5) during which the voltage is maintained, which is the storage time (delay time) after the first charge, is longer than the corresponding time (t2-t1) in the first example. At time t6, which is the first discharge, the pump 29 is driven, and lubricating oil is supplied to the bearing 11. The period from charge to discharge thereafter may be shorter than the first time. For example, the third discharge occurs at time t7 (t7<3t6).

[0325] <Operation and Effect> In the bearing device 10 of this embodiment, the lubricating oil supply unit 20 further includes another Peltier element 24b, another storage circuit (second storage circuit 17B) capable of storing electricity, and a pump 29. The pump 29 supplies lubricating oil 38 from a holding portion (lubricating oil tank 30) to the inside of the bearing 11. The other Peltier element 24b generates electricity in accordance with the temperature difference between the outer ring 13 side (first thermal conductor 23a2 side) and the inner ring 14 side (second thermal conductor 23b2 side) of the lubricating oil supply unit 20 in the radial direction, and supplies the electricity to the second storage circuit 17B. After a preset time has elapsed since the voltage of the second storage circuit 17B reaches the drive voltage of the pump 29, the pump 29 is driven, and the second storage circuit 17B repeatedly charges and discharges, thereby enabling drive control of the pump 29.

[0326] For example, as in embodiment 8, if there is only one Peltier element 24, the single Peltier element 24 may have two functions: power generation through the Seebeck effect and heat generation due to a thermal gradient through the Peltier effect. In this case, however, in order to increase the heat absorption and dissipation effect using the Peltier effect, the temperature difference around the Peltier element 24 becomes excessively large. The thermal stress caused by this temperature difference increases the pressure on the surfaces of the rolling elements 15 of the bearing 11. If this high pressure is applied to the lubricating oil, the film of lubricating oil supplied to the bearing 11 side may be broken, and there is a concern that the lubricating effect of the lubricating oil on the bearing 11 may be reduced.

[0327] However, according to the present embodiment, as described above, the Peltier element 24a is used for the Peltier effect (to generate heat) and the other Peltier element 24b is used for the Seebeck effect (to generate electromotive force). In other words, by dividing the roles of each element into the Peltier element 24a for generating heat and the other Peltier element 24b for generating electromotive force, the other Peltier element 24b can generate electromotive force without absorbing or dissipating heat. This allows the second power storage circuit 17B to be repeatedly charged and discharged regardless of the operation of the first power storage circuit 17A. This allows the pump 29 to be driven after a preset time has elapsed since the drive voltage of the pump 29 is reached, thereby appropriately controlling the timing of supplying lubricating oil to the bearing 11. For example, consider a case where the temperature difference between the first thermal conductor 23a2 and the second thermal conductor 23b2 is large, resulting in insufficient lubrication of the bearing 11. In this case, the charge / discharge cycle (time interval) can be shortened, thereby increasing the number of times lubricating oil is discharged to the bearing 11 per unit time. This makes it possible to suppress a decrease in lubricating effect caused by a break in the oil film.

[0328] The power generating unit 25B generates electricity from the temperature difference between the outer ring 13 and inner ring 14 of the bearing 11. However, in this case, the power generating unit 25B particularly uses the temperature difference between the outer ring spacer outer ring 33A and the outer ring spacer inner ring 33B. Therefore, when the temperature difference is large, the amount of electricity generated increases. In this case, it is preferable to shorten the charging time and shorten the interval between lubricating oil supplies, as shown in Figure 63, for example. Conversely, when the temperature difference is small, it is preferable to lengthen the charging time and lengthen the interval between lubricating oil supplies, as shown in Figure 64, for example.

[0329] Additionally, it is also possible to control the second storage circuit 17B as shown in these figures, depending on the amount of power generated by the power generation unit 25B. For example, if the time when the voltage required to drive the pump 29 is reached through charging is before the required timing for supplying lubricating oil, the second storage circuit 17B is controlled as shown in Figure 62. In other words, even after the fully charged voltage is reached, a predetermined storage time (delay time) is added, and management is performed so that the time for supplying lubricating oil is delayed.

[0330] Furthermore, in the case of a grease-sealed rolling bearing 11, sufficient lubrication can be ensured by the grease sealed in the bearing 11 at the beginning of operation. For this reason, as shown in Figure 65, the initial supply of lubricating oil may be started after the lubrication life of the grease sealed in the bearing 11 has expired. In this way, delaying the initial supply of lubricating oil extends the life of the bearing 11, and the time until maintenance can be extended.

[0331] The control circuit 27 changes the drive of the second storage circuit 17B in accordance with the amount of power generated by the power generation unit 25B, for example, when the detection value of the temperature sensor or bearing rotation sensor of the drive circuit 28 exceeds or falls below an arbitrarily set threshold value.

[0332] (Embodiment 13) <Configuration of Bearing Device> Fig. 66 is a schematic side view of a bearing device according to a first example of Embodiment 13. Referring to Fig. 66, in bearing device 10 according to this embodiment, first heat conduction member 23aa extends in an arc shape so as to contact the outer peripheral surface of outer ring spacer outer ring 33A connected to first heat conductor 23a. In this respect, this embodiment differs in configuration from Embodiment 8 (Fig. 43), in which first heat conduction member 23aa is connected to first heat conductor 23a and extends in an arc shape from there so as to contact the inner peripheral surface of outer ring spacer outer ring 33A. As shown in Fig. 66, first heat conduction member 23aa may extend so as to contact the entire circumferential surface of outer ring spacer outer ring 33A.

[0333] Although not shown in FIG. 66, a first thermal conductive member 23aa may also be connected to first thermal conductor 23a in this embodiment.

[0334] Fig. 67 is a schematic side view of a bearing device according to a second example of Embodiment 13. Referring to Fig. 67, first heat conduction member 23aa may extend so as to contact only a portion of outer ring spacer outer ring 33A in the circumferential direction. For example, first heat conduction member 23aa may not contact an area radially outward of drive circuit 28. In other words, first heat conduction member 23aa may contact only an area in the circumferential direction other than the area where drive circuit 28 is disposed.

[0335] <Effects> The examples of Figures 66 and 67 can also achieve effects similar to those of the example of Figure 43. Heat is absorbed by the first thermal conductor 23a, and then by the outer ring spacer outer ring 33A in contact therewith. Heat is also absorbed by the first thermal conduction member 23aa. Because copper or aluminum forming the first thermal conduction member 23aa has high thermal conductivity, heat is absorbed entirely in a short time. This further cools the outer ring spacer outer ring 33A in contact with the first thermal conduction member 23aa. As long as the first thermal conduction member 23aa can be rapidly cooled, the first thermal conduction member 23aa may be disposed radially outward of the outer ring spacer outer ring 33A.

[0336] Fourteenth Embodiment <Configuration of Mechanical Device> With reference to FIGS. 68 and 69, the configuration of a spindle for a machine tool, which is an example of a mechanical device to which the bearing devices according to the eighth to thirteenth embodiments are applied, will be described.

[0337] FIG. 68 is a schematic cross-sectional view of a mechanical device to which the bearing device shown in FIG. 43 is applied. FIG. 69 is a schematic cross-sectional view of the mechanical device shown in FIG. 68. FIG. 68 includes a schematic cross-sectional view of a portion taken along line LXVIII-LXVIII in FIG. 69. Referring to FIGS. 68 and 69, a machine tool spindle 50 serving as a mechanical device according to this embodiment mainly includes a rotating shaft 51, a spindle housing 52, an outer peripheral housing 53, and a bearing device 10 (see FIG. 43). The spindle housing 52 (housing) is disposed on the outer peripheral side of the rotating shaft 51 so as to surround the periphery of the rotating shaft 51. The outer peripheral housing 53 is disposed on the outer periphery of the spindle housing 52. The bearing device 10 rotatably supports the rotating shaft 51 relative to the spindle housing 52.

[0338] Two bearing devices are disposed on the outer periphery of the rotating shaft 51. The inner ring 14 and inner ring spacer 34 of the bearing device are fitted and fixed to the side surface of the rotating shaft 51. The outer ring 13 and outer ring spacer outer ring 33A of the bearing are fitted and fixed to the inner circumferential surface of the spindle housing 52. The bearing including the inner ring 14, outer ring 13, and rolling elements 15 (balls) disposed between the inner ring 14 and outer ring 13 is an angular contact ball bearing. A lubricating oil supply unit 20 is disposed between the outer ring spacer outer ring 33A and outer ring spacer inner ring 33B, which are disposed adjacent to the bearings. Another spacer is fitted and fixed to the rotating shaft 51 and spindle housing 52 between the two bearings (on the side opposite to the side where the lubricating oil supply unit is disposed) and abuts against the inner ring 14 and outer ring 13.

[0339] A through-hole is formed in an area facing the control circuit 27 of the lubricating oil supply unit, penetrating the outer ring spacer outer ring 33A, the spindle housing 52, and the outer housing 53. A flat portion is provided on the surface of the outer housing 53 at the outer peripheral end of the through-hole, and a pedestal 57 is disposed on the flat portion. An output board 56 is disposed on the pedestal 57. The output board 56 and the control circuit 27 of the lubricating oil supply unit 20 are electrically connected, for example, by a contact probe 54. The contact probe 54 is disposed inside the through-hole. One end of the contact probe 54 contacts an electrode pad (not shown) of the control circuit 27, and the other end of the contact probe 54 is connected to the output board 56 by a conductive wire 55. The contact probe 54 may be fixedly connected to the output board 56. The output board 56 and the control circuit 27 may be connected by wire as described above, or may be connected by other connection means (for example, optical communication means using a light-emitting element and a light-receiving element).

[0340] A cover member 58 is fixed to the base 57 so as to cover the output board 56 arranged on the base 57. A battery, which is a power source for driving the circuit of the output board 56, and a storage unit are arranged on the output board 56. The battery may be, for example, a coin battery or a button battery. A lithium battery is preferably used as the battery. A holder for securing such a battery is arranged on the surface of the output board 56. The storage unit may also include a holding unit (slot) for connecting and securing an external storage medium, for example, a card-type external storage medium, and the external storage medium removably secured to the holding unit. Any conventionally known storage medium, such as a memory card, may be used as the external storage medium.

[0341] The cover member 58 has a U-shaped elongated hole (a hole for arranging a fixing bolt) formed therein so that the cover member 58 can be removed from the base 57 simply by loosening the fixing bolt 59 that connects the cover member 58 to the base 57. The battery and external storage medium can be replaced with the cover member 58 removed from the base 57.

[0342] The output board 56, sealed by the base 57 and cover member 58, constitutes the main part of the voltage monitoring unit. The base 57 and cover member 58 can be provided with any waterproof structure to prevent the intrusion of coolant used during machining using the machine spindle. Examples of waterproof structures that can be used include packing, O-rings, caulking, and resin molding.

[0343] The machine tool spindle 50 described above also includes a unit main body and a lubricating oil supply unit. The unit main body is connected to the bearing 11 (see FIG. 44) including the inner ring 14, outer ring 13, and rolling elements 15 as described above, and includes a control unit having a control circuit 27 (see FIG. 43). The lubricating oil supply unit includes an external output unit 70, which is a voltage monitoring unit connected to the control unit by a connection line (contact probe 54).

[0344] The unit main body includes a control unit, a power supply unit, a lubricant supply unit, and a lubricant storage unit (lubricant tank 30). The control unit includes a control circuit 27. The power supply unit includes a heat absorption / radiation unit 25 (see FIG. 43) and a power supply circuit 26 (see FIG. 43). The lubricant supply unit includes the power supply circuit 26, a drive circuit 28, and a pump 29. The control unit is connected to the power supply unit and the lubricant supply unit. The control unit controls the lubricant supply state in the lubricant supply unit and acquires data related to the lubricant supply state. Examples of this data include the timing of lubricant supply, the interval between lubricant supply, and data on the voltage (storage voltage) in the power supply circuit (specifically, the power storage unit) when the pump 29 is operated.

[0345] Any configuration can be adopted as the connection between the control circuit 27 of the control unit and the output board 56 of the external output unit 70. However, for example, the calculation unit (microcomputer) installed in the control circuit 27 and the calculation unit of the output board 56 may be connected by a connection wire. The calculation unit of the control circuit 27 is connected to a power source and a ground by wiring or the like. Furthermore, on the output board 56, the calculation unit is connected to a battery and a memory unit. A signal (a signal transmitted from the control circuit 27) indicating data such as voltage can be transmitted from the calculation unit to the memory unit.

[0346] With the above configuration, data related to the lubricant supply status transmitted from the control circuit 27 is stored in the memory unit of the output board 56. The timing for transmitting the data from the control circuit 27 to the output board 56 can be any timing. However, for example, the data may be transferred from the control circuit 27 to the output board 56 when the memory unit of the control circuit 27 (such as a memory element included in the calculation unit or a memory element provided in the control circuit 27 independently of the calculation unit) becomes full with the data. If the data includes data on the time change in the stored voltage of the power supply unit, the data can be saved in an external storage medium via the memory unit of the output board 56 and then imported into an external computer or the like using the external storage medium. In this way, the status of the lubricant supply unit (such as the power generation status and the operating status of the pump 29) can be checked on the external computer.

[0347] <Operation of Mechanical Device> In a machine tool spindle 50, which is an example of a mechanical device shown in Figures 68 and 69, a rotating shaft 51 is connected to a predetermined drive shaft and is rotatable relative to a spindle housing 52. In a bearing device that supports the rotating shaft 51, a lubricating oil supply unit periodically supplies lubricating oil to bearings 11 (see Figure 44). This improves the reliability and durability of the machine tool spindle 50.

[0348] The timing of oil supply to the bearing 11 by the lubricating oil supply unit 20 in the bearing device 10 is arbitrary. However, when the rotating shaft 51 rotates at high speed, a swirling air flow occurs around the rolling elements 15 as the bearing 11 rotates. This can cause the lubricating oil to spread, which can hinder smooth delivery of the lubricating oil. Therefore, from the perspective of avoiding such problems, it is preferable to oil the bearing 11 while the bearing 11 is stopped or when the bearing 11 is rotating at a rotational speed with a dn value of 200,000 or less.

[0349] <Operation and Effect> The mechanical device (machine tool spindle 50) according to this embodiment includes a rotating shaft 51, a housing (spindle housing 52) disposed on the outer periphery of the rotating shaft 51, and the bearing device 10 that rotatably supports the rotating shaft 51 relative to the housing. This allows the bearing device 10 to operate stably for a long period of time, which in turn allows the mechanical device to operate stably for a long period of time.

[0350] The presently disclosed embodiments 1 to 14 should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0351] The various aspects of the present disclosure (with some exceptions) are described below as appendices. (Appendix 101) A bearing device comprising: a bearing; and a lubricant oil supply unit that supplies lubricant oil to the bearing, wherein the bearing includes a plurality of rolling elements arranged on an annular track, and a cage that holds the plurality of rolling elements, the cage having a cage inner diameter surface formed on its inner diameter side in the radial direction, the lubricant oil supply unit including: a holder that holds lubricant oil to be supplied to the inside of the bearing, and a nozzle member that supplies the lubricant oil from the holder to the inside of the bearing, the nozzle member having a tip surface that is a flat surface for forming oil droplets of the lubricant oil toward the cage inner diameter surface.

[0352] (Appendix 102) The bearing device according to appendix 101, wherein the nozzle member is made of a resin material.

[0353] (Supplementary Note 103) The bearing device according to Supplementary Note 101 or 102, wherein the nozzle member is either annular or block-shaped with a circumferentially cut-out portion of the annular shape.

[0354] (Appendix 104) A bearing device according to any one of Appendices 101 to 103, wherein the nozzle member is formed with a hole portion that reaches the tip end surface, the hole portion circulates and discharges the lubricating oil to be supplied to the inside of the bearing, a center line of the hole portion intersects with the inner diameter surface of the retainer in a cross section along the axial direction, and an angle θ1 formed by the center line of the hole portion on the lubricating oil supply unit side in the axial direction intersecting with the inner diameter surface of the retainer is greater than 0° and not greater than 90°.

[0355] (Appendix 105) A bearing device as described in Appendix 104, wherein the angle θ2 formed by the tip surface of the nozzle member and the side of the surface of the nozzle member adjacent to the tip surface on the lubricating oil supply unit side in a cross section along the axial direction is greater than 0° and not more than (θ1 + 90)°.

[0356] (Appendix 106) The bearing device according to any one of appendices 101 to 105, wherein the planar shape of the tip end surface is either circular or triangular.

[0357] (Supplementary Note 107) The bearing device according to any one of Supplementary Notes 101 to 105, wherein the planar shape of the tip end surface is a polygon having four or more vertices.

[0358] (Appendix 108) The bearing device according to any one of appendices 101 to 107, wherein the lubricating oil is sealed in the bearing in advance, and the sealed lubricating oil is grease.

[0359] (Supplementary Note 109) A mechanical device comprising: a rotating shaft; a housing arranged on the outer periphery of the rotating shaft; and the bearing device according to any one of Supplementary Notes 101 to 108, which rotatably supports the rotating shaft relative to the housing.

[0360] (Appendix 201) A bearing device comprising: a bearing; and a lubricating oil supply unit that supplies lubricating oil to the bearing, wherein the bearing includes an outer ring having an outer ring rolling surface on its inner circumferential surface, and an inner ring having an inner ring rolling surface on its outer circumferential surface and arranged inside the outer ring so that the inner ring rolling surface faces the outer ring rolling surface, and the lubricating oil supply unit includes: a retaining portion that retains lubricating oil to be supplied to the inside of the bearing, a Peltier element, a first thermal conductor and a second thermal conductor that sandwich the Peltier element, and a power source that can supply power to the Peltier element, wherein heat can be transferred from the first thermal conductor to the second thermal conductor by driving the Peltier element with the power source.

[0361] (Appendix 202) A bearing device as described in Appendix 201, including a spacer arranged to sandwich the lubricating oil supply unit, the spacer contacting the bearing, the first heat conductor being able to absorb heat from the spacer when the Peltier element is driven, and the second heat conductor being able to radiate heat to the retaining portion when the Peltier element is driven.

[0362] (Supplementary Note 203) The bearing device according to Supplementary Note 202, wherein the Peltier element, the first thermal conductor, the second thermal conductor, and the power source are installed in the spacer connected to a fixed ring that is one of the outer ring and the inner ring.

[0363] (Supplementary Note 204) The bearing device according to Supplementary Note 202 or 203, wherein a first heat conducting member is connected to the first heat conductor, and a second heat conducting member is connected to the second heat conductor.

[0364] (Supplementary Note 205) The bearing device according to Supplementary Note 204, wherein the first heat conducting member and the second heat conducting member are primarily composed of either copper or aluminum.

[0365] (Supplementary Note 206) The bearing device according to Supplementary Note 204 or 205, wherein the first heat conducting member is in contact with the spacer, and the second heat conducting member is in contact with the retaining portion.

[0366] (Appendix 207) A bearing device described in any one of Appendices 204 to 206, wherein the holding portion includes a resin bag body, a movable piece is connected to either the second heat conductor or the second heat conduction member, the movable piece is formed from a bimetal, the movable piece is in contact with the holding portion, and is capable of pressing the bag body in accordance with the displacement of the movable piece to change the volume of the bag body.

[0367] (Appendix 208) The bearing device according to any one of appendices 201 to 207, wherein the lubricating oil supply unit further includes a storage circuit capable of storing electricity, and the Peltier element operates as a generator and is switchable between a first state in which electricity is stored in the storage circuit and a second state in which the electricity stored in the storage circuit is supplied to the Peltier element and heat is transferred from the first thermal conductor to the second thermal conductor.

[0368] (Appendix 209) The bearing device according to any one of Appendices 201 to 208, wherein the lubricating oil supply unit further includes another Peltier element, another power storage circuit capable of storing electricity, and a pump that supplies the lubricating oil from the holding portion to the inside of the bearing, wherein the other Peltier element generates electricity according to a temperature difference in the radial direction between the outer ring side and the inner ring side of the lubricating oil supply unit, and supplies power to the other power storage circuit, and wherein the pump is driven after a preset time has elapsed from the time when the voltage of the other power storage circuit reaches a drive voltage of the pump, and the other power storage circuit is capable of repeatedly charging and discharging, thereby controlling the drive of the pump.

[0369] (Appendix 210) The bearing device according to any one of appendices 201 to 209, wherein the lubricating oil is sealed in the bearing in advance, and the sealed lubricating oil is grease.

[0370] (Appendix 211) A mechanical device comprising: a rotating shaft; a housing arranged on the outer periphery of the rotating shaft; and the bearing device according to any one of Appendices 201 to 210, which rotatably supports the rotating shaft relative to the housing.

[0371] 10 Bearing device, 11 Bearing, 13 Outer ring, 14 Inner ring, 14a Inclined portion, 15 Rolling element, 16 Cage, 16b Cage inner diameter surface, 17A First power storage circuit, 17B Second power storage circuit, 20 Lubricating oil supply unit, 21 Housing body, 22 Cover body, 23a, 23a1, 23a2 First heat conductor, 23aa First heat conduction member, 23b, 23b1, 23b2 Second heat conductor, 23bb Second heat conduction member, 23cc Movable piece, 24 Peltier element (thermoelectric element), 24a Peltier element, 24b Other Peltier elements, 25 Power generation unit (heat absorption and heat dissipation unit), 25A Heat absorption and heat dissipation unit, 25B Power generation unit, 26 Power supply circuit, 26A First power supply circuit, 26B Second power supply circuit, 27 Control circuit, 27A First control circuit, 27B Second control circuit, 28 Drive circuit, 29 Pump, 30 Lubricating oil tank, 30a Outer frame, 30b Bag body, 31 Suction tube, 32 Discharge tube, 32a Nozzle, 33 Outer ring spacer, 33A Outer ring spacer outer ring, 33B Outer ring spacer inner ring, 33C Interposition portion, 34 Inner ring spacer, 35 Wiring, 35A First wiring, 35B Second wiring, 36 Gap, 37, 37B1, 37B2 Nozzle member, 37a Nozzle hole, 37b Land portion, 37bb Land portion forming surface, 37c Side surface, 37d Surface, 37IF Radial innermost surface, 37IS, 37IS1, 37IS2 Shaft innermost surface, 37OF Radial outermost surface, 37OS Shaft outermost surface, 38 Oil droplet (lubricating oil), 38A Lubricating oil, 41 sealing groove, 42 sealing member, 50 machine tool spindle, 51 rotating shaft, 52 spindle housing, 53 outer peripheral housing, 54 contact probe, 55 conductive wire, 56 output board, 57 base, 58 cover member, 59 fixing bolt, 70 external output unit, 101 bearing device, 102 bearing, 102a, 102b end face, 103 spacer, 104 lubricating oil supply unit, 110 inner ring, 110a, 110b end face, 111 outer peripheral surface, 112 inner ring rolling surface, 113 inclined portion, 113r recess, 114 outer ring, 114a, 114b end face, 115 inner peripheral surface, 116 outer ring rolling surface, 117 rolling element, 118 cage, 119, 148 Seal member, 121, 155 Inner ring spacer, 122, 156 Outer ring spacer, 123 Protrusion, 125 Tank, 125a First tank portion, 125b Second tank portion, 126 Lubricating oil, 126d Drop, 128,128b Tube, 130 Pump, 132 Power supply unit, 133 Power generation unit, 133a, 133b Heat conductor, 133c Thermoelectric element, 134 Charging unit, 135 Voltage sensor, 136 Controller, 137, 137b Housing, 138, 138b Housing body, 139, 139b Lid, 140 Supply path member, 141 Tube, 142 Nozzle member, 142a Surface portion, 144 Inlet, 145 Outlet, 146 Outlet path, 147 Inlet, 150 Mechanical device, 151 Shaft, 152 Inner housing, 153 Outer housing, 154 Spacer, 157 Motor, 158 Rotation sensor, 159 Mechanical controller, 160, 160b Float, CR Cross section, L0, L1 Center line, L2 Straight line, TR end face. ,

Claims

1. A lubricating oil supply unit comprising: a tank for storing lubricating oil; a pump; and a supply path member fluidly communicating with the pump, wherein the pump supplies the lubricating oil from the tank to the supply path member, the supply path member being arranged at the bottom of the lubricating oil supply unit and including an inlet connected to the pump, a discharge port facing the interior of a bearing to which the lubricating oil supply unit is attached and for discharging the lubricating oil into the interior of the bearing, and a discharge path connected to the discharge port and extending upward.

2. The lubricating oil supply unit according to claim 1, wherein the tank is made of a material having a thermal conductivity of 0.10 W / (m·K) or more, and the material is polycarbonate resin.

3. A lubricating oil supply unit as described in claim 1, wherein the supply path member includes a nozzle member including the discharge port and the discharge path, the nozzle member has an arc shape that is part of a ring centered on the axis of the bearing, and the end of the nozzle member in the circumferential direction of the bearing has a tapered shape or a streamlined shape.

4. The lubricating oil supply unit according to claim 1, wherein the supply path member includes a nozzle member including the discharge port and the discharge path, and the discharge port is provided on a flat surface of the nozzle member.

5. The lubricant supply unit of claim 1, further comprising a float disposed within said tank and capable of floating relative to said lubricant.

6. The lubricating oil supply unit according to claim 1, further comprising a controller that controls the operation of the pump, wherein the controller controls the operation of the pump so that the droplets of lubricating oil formed at the discharge port adhere to the inside of the bearing.

7. A lubricating oil supply unit as described in claim 1, further comprising: a controller for controlling the operation of the pump; and a rotation sensor for detecting rotation of a shaft rotatably supported by the bearing, wherein the controller controls the operation of the pump based on an output from the rotation sensor, and when the rotation of the shaft is stopped or when the bearing is being used with a dn value of 200,000 or less, the controller operates the pump to supply the lubricating oil from the tank to the interior of the bearing.

8. A lubricating oil supply unit according to claim 6 or claim 7, further comprising a power supply unit that generates electric power and supplies the electric power to the controller, wherein the controller and the tank are arranged side by side in the axial direction of the bearing, and the power supply unit and the tank are arranged side by side in the axial direction of the bearing.

9. A bearing device comprising: the lubricating oil supply unit according to any one of claims 1 to 7; and the bearing to which the lubricating oil supply unit is attached, wherein the bearing comprises an outer ring including an outer ring rolling surface on its inner circumferential surface, an inner ring including an inner ring rolling surface on its outer circumferential surface and arranged inside the outer ring so that the inner ring rolling surface faces the outer ring rolling surface, and a plurality of rolling elements that roll on the outer ring rolling surface and the inner ring rolling surface, wherein the outer circumferential surface of the inner ring includes an inclined portion that extends from an end face of the inner ring in the axial direction of the bearing to the inner ring rolling surface and approaches the outer ring as it moves from the end face of the inner ring to the inner ring rolling surface, wherein the interior of the bearing is the inclined portion, and the inclination angle of the inclined portion relative to the axial direction of the bearing is between 1° and 45°, and wherein the inclined portion is provided with a recess for storing the lubricating oil, and the discharge port faces the recess.

10. A mechanical device comprising: the lubricating oil supply unit according to claim 7; the bearing to which the lubricating oil supply unit is attached; the shaft rotatably supported by the bearing; a motor that rotates the shaft; and a machine controller that controls the motor, wherein the machine controller operates the motor to rotate the shaft while the controller stops the operation of the pump.

11. A bearing device comprising: a bearing; and a lubricating oil supply unit that supplies lubricating oil to the bearing, wherein the bearing includes a plurality of rolling elements arranged in a row on a circular track; and a retainer that holds the plurality of rolling elements, the retainer having a retainer inner diameter surface formed on its inner diameter side in the radial direction, and the lubricating oil supply unit including a retaining portion that holds lubricating oil to be supplied to the inside of the bearing; and a nozzle member that supplies the lubricating oil from the retaining portion to the inside of the bearing, the nozzle member having a tip surface that is a flat surface that causes the lubricating oil to form oil droplets toward the retainer inner diameter surface.

12. The bearing device according to claim 11, wherein the nozzle member is made of a resin material.

13. A bearing device according to claim 11 or 12, wherein the nozzle member is either annular or block-shaped with a circumferentially cut-away portion of the annular shape.

14. A bearing device as described in claim 11 or 12, wherein the nozzle member is formed with a hole portion that reaches the tip surface, the hole portion circulates and discharges the lubricating oil to be supplied to the inside of the bearing, the center line of the hole portion intersects with the inner diameter surface of the retainer in a cross section along the axial direction, and the angle θ1 at which the center line of the hole portion on the lubricating oil supply unit side in the axial direction intersects with the inner diameter surface of the retainer is greater than 0° and not greater than 90°.

15. A bearing device as described in claim 14, wherein the angle θ2 formed by the tip surface of the nozzle member and the side surface of the nozzle member adjacent to the tip surface on the lubricating oil supply unit side in a cross section along the axial direction is greater than 0° and not more than (θ1 + 90)°.

16. A bearing device according to claim 11 or 12, wherein the planar shape of the tip surface is either circular or triangular.

17. A bearing device according to claim 11 or 12, wherein the planar shape of the tip surface is a polygon having four or more vertices.

18. A bearing device according to claim 11 or 12, wherein the lubricating oil is sealed in the bearing beforehand, and the sealed lubricating oil is grease.

19. A mechanical device comprising: a rotating shaft; a housing arranged on the outer periphery of said rotating shaft; and a bearing device according to claim 11 or 12 that rotatably supports said rotating shaft relative to said housing.

20. A bearing device comprising: a bearing; and a lubricating oil supply unit that supplies lubricating oil to the bearing, wherein the bearing includes an outer ring having an outer ring rolling surface on its inner circumferential surface, and an inner ring having an inner ring rolling surface on its outer circumferential surface and arranged inside the outer ring so that the inner ring rolling surface faces the outer ring rolling surface, and the lubricating oil supply unit includes: a retaining portion that retains lubricating oil to be supplied to the inside of the bearing, a Peltier element, first and second thermal conductors that sandwich the Peltier element, and a power supply that can supply power to the Peltier element, wherein heat can be transferred from the first thermal conductor to the second thermal conductor by driving the Peltier element with the power supply.

21. A bearing device as described in claim 20, further comprising a spacer arranged to sandwich the lubricating oil supply unit, the spacer being in contact with the bearing, the first heat conductor being able to absorb heat from the spacer when the Peltier element is driven, and the second heat conductor being able to radiate heat to the retaining portion when the Peltier element is driven.

22. A bearing device according to claim 21, wherein the Peltier element, the first heat conductor, the second heat conductor and the power source are installed in the spacer connected to a fixed ring which is either the outer ring or the inner ring.

23. A bearing assembly according to claim 21, wherein a first heat conducting member is connected to the first heat conducting body, and a second heat conducting member is connected to the second heat conducting body.

24. The bearing device according to claim 23, wherein the first heat conducting member and the second heat conducting member are primarily made of either copper or aluminum.

25. The bearing device according to claim 23, wherein the first heat conducting member contacts the spacer and the second heat conducting member contacts the retainer.

26. A bearing device as described in claim 23, wherein the retaining portion includes a resin bag, a movable piece is connected to either the second heat conductor or the second heat conducting member, the movable piece is formed from a bimetal, the movable piece is in contact with the retaining portion, and the volume of the bag can be changed by pressing the bag in accordance with the displacement of the movable piece.

27. A bearing device according to claim 20 or 21, wherein the lubricating oil supply unit further includes a storage circuit capable of storing electricity, and the Peltier element operates as a generator and is switchable between a first state in which electricity is stored in the storage circuit and a second state in which the electricity stored in the storage circuit is supplied to the Peltier element, causing heat to be transferred from the first thermal conductor to the second thermal conductor.

28. A bearing device according to claim 20 or 21, wherein the lubricating oil supply unit further includes another Peltier element, another storage circuit capable of storing electricity, and a pump that supplies the lubricating oil from the retaining portion to the inside of the bearing, wherein the other Peltier element generates electricity in accordance with the temperature difference in the radial direction between the outer ring side and the inner ring side of the lubricating oil supply unit and supplies power to the other storage circuit, and wherein the pump is driven after a preset time has elapsed from the point at which the voltage of the other storage circuit reaches the drive voltage of the pump, and the other storage circuit is capable of repeatedly charging and discharging, thereby controlling the drive of the pump.

29. A bearing device according to claim 20 or 21, wherein the lubricating oil is sealed in the bearing beforehand, and the sealed lubricating oil is grease.

30. A mechanical device comprising: a rotating shaft; a housing arranged on the outer periphery of said rotating shaft; and a bearing device according to claim 20 or 21 that rotatably supports said rotating shaft relative to said housing.

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