Rotating Table Device

Abstract

To provide a lubrication system instead of using grease.SOLUTION: A rotary table device comprises: a table body; a rotary table that can rotate around a central axis in a vertical direction; a bearing device that supports the rotary table to the table body in a vertical direction and a radial direction; a motor that rotates the rotary table; and a lubricating oil supply device that supplies lubricating oil to the bearing device. The bearing device comprises a first bearing member mounted on the table body, and a second bearing member mounted on the rotary table. As for the first bearing member and the second bearing member, an inner diameter side of the first bearing member is fitted in an annular groove formed on the outer circumference of the second bearing member, and an upper roller row, a lower roller row and a side roller row are arranged on an upper surface, a lower surface and a side surface that face the second bearing member of the first bearing member fitted in the second bearing member, respectively, and the lubricating oil supply device has a nozzle for supplying a predetermined amount of lubricating oil to the upper roller row.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a rotary table device for a machine tool. [Background technology]

[0002] The rotary table device of Patent Document 1 has a bearing between the table body and the spindle. In order to improve the runout accuracy, coaxiality, and rigidity of the table, a three-roller bearing may be used as the bearing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-161995 Summary of the Invention [Problem to be solved by the invention]

[0004] Grease is generally used as a lubricant in three-roller bearings. When using grease as a lubricant, the appropriate amount of grease is filled into the lubrication area. Grease maintenance, which is carried out about once a year, requires the old grease to be removed. However, the bearing area of ​​the center table of a machine tool is often surrounded by other parts, so removing the old grease and refilling it with new grease is a significant effort. Therefore, there is a demand for a lubrication method that is easy to maintain. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms.

[0006] (1) According to one aspect of the present disclosure, there is provided a rotary table device comprising: a table body; a rotary table rotatable about a vertical central axis; a bearing device supporting the rotary table relative to the table body in the up-down and radial directions; a motor for rotating the rotary table; and a lubricating oil supply device for supplying lubricating oil to the bearing device, the bearing device comprising a first bearing member attached to the table body and a second bearing member attached to the rotary table, the first bearing member and the second bearing member being configured such that the inner diameter side of the first bearing member is fitted into an annular groove formed in the outer periphery of the second bearing member, and the first bearing member fitted to the second bearing member has an upper roller row, a lower roller row, and a side roller row disposed on an upper surface, a lower surface, and a side surface facing the second bearing member, respectively; and the lubricating oil supply device having a nozzle for supplying a predetermined amount of lubricating oil to the upper roller row. The rotary table device is provided with a lubricating oil recovery groove below the bearing device and a drain hole for discharging the lubricating oil from the lubricating oil recovery groove to the outside of the rotary table device, and has a drain shape that separates the fall path along which the lubricating oil falls from the lower roller row from the exhaust path from the lubricating oil recovery groove to the motor. With this type of rotary table device, the lubricating oil supplied to the upper roller row by the nozzle flows in the order of the upper roller row, the side roller row, and the lower roller row, so that the lubricating oil can be supplied to all the roller rows. Also, since there is no need to eliminate gaps between the rotating parts and the stationary parts, sliding resistance does not increase. Also, this According to the rotary table device of the above embodiment, excess lubricating oil can be recovered. Furthermore, According to the rotary table device of the embodiment, the lubricating oil does not flow into the exhaust path from the lubricating oil recovery groove to the motor, so that the influence of the lubricating oil on the motor can be suppressed. 。 (2)In the above-described rotary table apparatus, the lubricating oil supply device may include a lubricating oil pump, a distributor disposed downstream of the lubricating oil pump and configured to supply a constant amount of lubricating oil to the nozzle, an air pump, a solenoid valve disposed downstream of the air pump and configured to turn on and off the air supply, an air supply pipe connecting the distributor, the nozzle, and the solenoid valve, and a control unit configured to operate the lubricating oil pump for a predetermined first period at predetermined intervals, and to temporarily turn on the solenoid valve after a predetermined second period has elapsed to supply the constant amount of lubricating oil from the nozzle to the upper roller array using the air pressure. According to this rotary table apparatus, the control unit can operate the lubricating oil pump for a predetermined first period at predetermined intervals, and then temporarily turn on the solenoid valve after a predetermined second period has elapsed to supply an appropriate constant amount of lubricating oil from the nozzle to the upper roller array using the air pressure. (3) According to another aspect of the present disclosure, there is provided a rotary table device comprising: a table body, a rotary table rotatable about a vertical central axis, a bearing device supporting the rotary table relative to the table body in vertical and radial directions, a motor for rotating the rotary table, and a lubricating oil supply device for supplying lubricating oil to the bearing device, the bearing device comprising a first bearing member attached to the table body and a second bearing member attached to the rotary table, the first bearing member and the second bearing member being arranged such that the second bearing member is positioned around the vertical central axis, the inner diameter side of the first bearing member is fitted into an annular groove formed in the outer periphery of the second bearing member, and upper, lower, and side surfaces of the first bearing member fitted to the second bearing member facing the second bearing member, with the axial direction of the central axis being the up-down direction, on which an upper roller row, a lower roller row, and a side roller row are arranged, respectively, and the lubricating oil supply device has a nozzle for supplying a predetermined amount of lubricating oil to the upper roller row. (4) In the above-described rotary table apparatus, the lubricating oil supply device may include a plurality of nozzles for supplying the lubricating oil to the upper roller row, a lubricating oil pump, a distributor disposed downstream of the lubricating oil pump for measuring and distributing a quantity of the lubricating oil from the lubricating oil pump into a plurality of pipes, a plurality of nozzle pipes connecting the distributor to the plurality of nozzles, an air pump, a solenoid valve disposed downstream of the air pump for turning on and off the air supply, an air supply pipe connecting the nozzle pipe to the air output side of the solenoid valve between the distributor and the nozzle, and a control unit that operates the lubricating oil pump for a predetermined first time at predetermined intervals to fill the nozzle pipe with a certain quantity of the lubricating oil from the distributor, stops the operation of the lubricating oil pump, and then temporarily turns on the solenoid valve after a predetermined second time has elapsed to use the air pressure to supply the certain quantity of the lubricating oil from the nozzle to the upper roller row. (5) The present disclosure can be realized in various forms other than a rotary table device, such as a processing device or a machining center. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is an explanatory diagram of a five-axis machining center equipped with a rotary table device. [Figure 2] FIG. 2 is an explanatory diagram showing the configuration of a rotary table device. [Figure 3] FIG. 3 is an explanatory diagram showing an enlarged view of region III in FIG. 2. [Figure 4] 4 is an explanatory diagram showing a cross section of region III different from that of FIG. 3. FIG. [Figure 5] FIG. 4 is an explanatory diagram showing a VV cross section of FIG. 3. [Figure 6] FIG. 2 is an explanatory diagram of a lubricating oil supply system. [Figure 7] FIG. 4 is an explanatory diagram showing the operation timing of a lubricating oil pump and an air pump. DETAILED DESCRIPTION OF THE INVENTION

[0008] First embodiment: 1 is an explanatory diagram of a five-axis machining center 10 equipped with a rotary table device 30. The five-axis machining center 10 is equipped with a bed 20, the rotary table device 30, a turning spindle 70 with a built-in chuck device, a column 80, and a saddle 90. The five-axis machining center 10 is a horizontal type, with the vertical direction defined as the y-axis direction and the horizontal directions intersecting with the y-axis direction defined as the x-axis direction and z-axis direction.

[0009] Bed 20 includes a pair of rails 21 extending along the z-axis and a work table 25 in the -z direction of rails 21. A pair of rails 26 extending along the x-axis are disposed on work table 25. A rotary table device 30 is disposed on rails 26. Rotary table device 30 can be moved along the x-axis on rails 26 by a servo motor (not shown).

[0010] The rotary table device 30 has a rotary table 31, which is rotatable around the B axis. A turning spindle 70 with a built-in chuck device is arranged on the rotary table 31. The turning spindle 70 is also called the turning main shaft. The turning spindle 70 grips the workpiece 100 and can rotate the workpiece 100 around the A axis using a motor (not shown). The force used to grip the workpiece 100 is provided by hydraulic pressure supplied via the rotary table device 30. The supply route will be described later.

[0011] A column 80 is disposed on the rail 21, and the column 80 can be moved along the z-axis on the rail 21 by a servo motor (not shown). A pair of rails 81 extending along the y-axis are disposed on the column 80. A saddle 90 is disposed on the rail 81. The saddle 90 can be moved along the y-axis on the rail 81 by a servo motor 82. A spindle 91 is provided on the saddle 90, and a tool for machining the workpiece is attached to the spindle 91. The spindle 91 is also called the main shaft. A motor (not shown) rotates the spindle 91, causing the tool to rotate and machine the workpiece 100. By using a skiving tool as the tool, linking the rotation of the tool with the rotation of the workpiece 100, and moving the tool axially relative to the workpiece 100, skiving can be performed on the tooth surface of the workpiece 100. Using a rotary table device 30 (described later) improves the machining accuracy of the tooth surface.

[0012] 2 is an explanatory diagram showing the configuration of the rotary table device 30. The rotary table device 30 includes rotating rotation system components and non-rotating fixed system components. The rotary table device 30 includes, as rotation system components, a rotary table 31 (see FIG. 1; not shown in FIG. 2), a center sleeve 40, a first rotor 51, a second rotor 52, a rotor magnet 54 of the built-in motor, a second bearing member 55 of the rolling bearing, a first connecting portion 56 connecting the center sleeve 40 and the second connecting portion 57, the second connecting portion 57, a water-shedding member 58, and a rotor portion 63a inside the encoder. The rotary table device 30 also includes, as fixed system components, a table main body 60, a center shaft 61, an encoder mounting portion 62 connecting the center shaft 61 and the casing 63b, the casing 63b on the outer diameter side of the encoder, a housing 64, a housing support portion 65, a stator coil 66 of the built-in motor, a first bearing member 67 of the rolling bearing, and a groove forming member 59.

[0013] The table main body 60 includes a disk portion 60b that forms the bottom surface of the rotary table device 30 and a cylindrical portion 60a that rises from the outer periphery of the disk portion 60b. Here, the disk portion 60b side is referred to as the "bottom" and the direction from which the cylindrical portion 60a rises is referred to as the "top." An opening 60c is formed in the center of the disk portion 60b. This opening 60c accommodates cables and other signal lines (not shown) that transmit output from the outer casing 63b of the encoder to an external control device (not shown). The B-axis OB, which is the center of the table main body 60, passes through the center of the opening 60c. Hereinafter, the B-axis OB will also be referred to as the "center axis OB." The center axis OB is the rotation axis of the rotary table 31. A cylindrical center shaft 61, centered on the center axis OB, is erected on the disk portion 60b. A flange-shaped fixing portion 61a is formed at the lower end of the center shaft 61, and the fixing portion 61a is fixed to the disk portion 60b of the table main body 60 with screws (not shown). In FIG. 2, the screws used to fix the various components are not shown. On the opposite side of the center shaft 61 from the disk portion 60b (the upper side in FIG. 2), an encoder mounting portion 62 is fixed to the center shaft 61 with screws. The encoder mounting portion 62 is cylindrical and has a flange 62a on the side opposite the center shaft 61. On the opposite side of the flange 62a from the center shaft 61, a central portion 62b is recessed, and an encoder outer diameter side casing 63b is fixed to this recessed central portion 62b with screws. The encoder outer diameter side casing 63b is cylindrical and, together with a rotor portion 63a that rotates together with the turntable 31, constitutes a rotary encoder 63 that detects the rotation angle of the turntable 31. In this embodiment, a magnetic or optical rotary encoder can be used as the rotary encoder.

[0014] A center sleeve 40, which is a rotating system member, is disposed around the center shaft 61 with a small gap therebetween. The center sleeve 40 has a cylindrical shape concentric with the central axis OB. A flange 40a is formed on the side of the center sleeve 40 opposite the table body 60. A cylindrical first rotor 51, concentric with the central axis OB, is disposed around the outer periphery of the flange 40a. A cylindrical second rotor 52, concentric with the central axis OB, is disposed around the outer periphery of the first rotor 51. A rotor magnet 54 is disposed on the table body 60 side of the second rotor 52. The rotor magnet 54, together with a stator coil 66, a fixed system component, constitutes a direct drive motor (hereinafter referred to as the "motor"). A second bearing member 55, which is a rolling bearing, is disposed around the outer periphery of the second rotor 52. The second bearing member 55, which is a rolling bearing, together with a first bearing member 67, a fixed system component, constitutes a three-way bearing that provides vertical and radial support. The bearing structure will be described later. A table support part 56 is fixed with screws to the side of the flange 40a opposite the table main body 60. The table support part 56 has a cylindrical part 56a concentric with the central axis OB, and a perforated disk part 56b with a hole 56c formed in the center of the cylindrical part 56a on the rotary table 31 side (upper side in Figure 2). A second connecting part 57 is fitted into and fixed in the hole 56c.

[0015] A water-squeezing member 58 and a groove-forming member 59 are disposed below the second rotor 52 and the second bearing member 55. The groove-forming member 59 is disposed on the outer periphery of the water-squeezing member 58. Together with the cylindrical portion 60a of the table body 60, it forms a lubricant oil recovery groove 59a that collects lubricant oil that has fallen from the second bearing member 55. Because the water-squeezing member 58 is a rotating component, and the groove-forming member 59 is a stationary component, an exhaust path 581 is formed between the water-squeezing member 58 and the groove-forming member 59. The exhaust path 581 is used to exhaust air from the lubricant oil recovery groove 59a and to create a gap between the water-squeezing member 58, which is a rotating component, and the groove-forming member 59, which is a stationary component. The water-squeezing member 58 has a water-squeezing shape 58a that protrudes toward the lubricant oil recovery groove 59a. The water-squeezing shape 58a prevents lubricant oil that has fallen from the second bearing member 55 from flowing toward the exhaust path 581.

[0016] The center sleeve 40 has an outer peripheral surface with a circular cross section, and the housing 64 is disposed on the outside of the outer peripheral surface with a small gap therebetween and is fixed to the table main body 60 with screws. In other words, the center sleeve 40 and the housing 64 are disposed at a distance from each other. The housing 64 has a cylindrical shape with a central axis OB as its center. A housing support portion 65 is disposed on the outer peripheral side of the housing 64 and is fixed to the table main body 60 with screws. The housing support portion 65 supports the housing 64 from the outer peripheral side.

[0017] A stator coil 66 is disposed inside the cylindrical portion 60a of the table main body 60. As described above, this stator coil 66, together with the rotor magnet 54, constitutes a direct drive motor, which is a built-in motor.

[0018] The housing 64 has an inner peripheral surface with a circular cross section over a predetermined range along the central axis OB. The inner peripheral surface is formed with a plurality of recesses 64a each having an annular groove shape. O-rings 68 are disposed between the inner peripheral surface of the housing 64 and the outer peripheral surface of the center sleeve 40, one above the other and one below the recess 64a along the central axis OB. The O-rings 68 are sandwiched between the inner peripheral surface of the housing 64 and the outer peripheral surface of the center sleeve 40 to prevent leakage of fluid supplied to the recess 64a. Because sliding resistance occurs when the center sleeve 40 rotates, it is preferable to have a small number of O-rings 68. Since the O-ring 68 between two adjacent recesses 64a can be shared, if the number of recesses 64a is n, then n+1 O-rings 68 are sufficient. A plurality of internal fluid flow paths 64b are formed within the housing 64, each of which communicates with the recesses 64a. The fluid flow path 64b is composed of a radial bus hole communicating with the recess 64a and a passage extending in the axial direction.

[0019] A plurality of in-housing fluid flow paths 60d are formed in the cylindrical portion 60a and the disk portion 60b of the table main body 60, and are respectively connected to a plurality of in-housing fluid flow paths 64b of the housing 64. Fluid supply pipes 69, which are respectively connected to the plurality of in-housing fluid flow paths 60d, are connected to the cylindrical portion 60a and the disk portion 60b.

[0020] The center sleeve 40 has a plurality of fluid flow passages 40c formed therein, each connected to a corresponding one of the recesses 64a. The fluid flow passages 40 are comprised of a radial passage hole communicating with the recesses 64a and a passage extending in the axial direction. The fluid flow passages 40c are connected to a fluid flow passage (not shown) in the rotary table 31 via a plurality of fluid flow passages 51a formed inside the first rotor 51. The fluid flow passage in the rotary table 31 is connected to a turning spindle 70 incorporating a chuck device via a tube (not shown). The housing 64 and the center sleeve 40 form a so-called distributor that distributes the fluid. The number of recesses 64a corresponds to the number of fluids distributed by the distributor.

[0021] Fig. 3 is an explanatory diagram showing an enlarged view of region III in Fig. 2. Fig. 4 is a cross-sectional view of region III cut at a different cross section from that in Fig. 3. Fig. 5 is an explanatory diagram showing a cross section cut at line VV in Fig. 3. In the explanations of Figs. 3 to 5, the structure of the bearing and the structure related to the flow of lubricating oil will be explained, and explanations of other structures will be omitted.

[0022] The first bearing member 67 has a perforated disk shape with a substantially rectangular cross section when cut along a plane including the central axis OB, and the second bearing member 55 surrounds the first bearing member 67 from the upper, lower, and central axis OB side. The second bearing member 55 is formed of two members, a first member 55a and a second member 55b, to sandwich the first bearing member 67. After sandwiching the first bearing member 67, the first member 55a and the second member 55b are fixed together with screws (not shown). That is, the second bearing member 55 has an annular groove on its outer periphery, and the inner diameter side of the first bearing member 67 is fitted into the annular groove. The annular groove of the second bearing member 55 is composed of a lower surface, a side surface, and an upper surface, which respectively form an upper inner ring rolling surface, a side inner ring rolling surface, and a lower inner ring rolling surface. It has three surfaces at a position corresponding to the annular groove of first bearing member 67, which respectively serve as an upper outer ring side rolling surface, a side outer ring rolling surface, and a lower outer ring rolling surface. Between the upper inner ring rolling surface and the upper outer ring rolling surface is arranged upper roller array 671 held by retainer 681 that rolls therebetween, and the upper inner ring rolling surface, upper outer ring rolling surface, and upper roller array 671 constitute an upper bearing. Between the lower inner ring rolling surface and lower outer ring rolling surface is arranged lower roller array 672 held by retainer 682 that rolls therebetween, and the lower inner ring rolling surface, lower outer ring rolling surface, and lower roller array 672 constitute a lower bearing. Between the side inner ring rolling surface and the side outer ring rolling surface, a side roller array 673 is arranged on the side of the first bearing member 67 that rolls on them, facing the second bearing member 55. The side inner ring rolling surface, the side outer ring rolling surface, and the side roller array 673 form a side bearing. The upper and lower bearings support the second bearing member 55 in the vertical direction relative to the first bearing member 67, and the side bearings support the second bearing member 55 in the radial direction relative to the first bearing member 67. The rollers that form the upper roller array 671, the lower roller array 672, and the side roller array 673 are all cylindrical. The use of cylindrical rollers increases the contact area between the rollers and the rolling surfaces, increasing the vertical and radial support load of the second bearing member 55 against the first bearing member 67. A nozzle 174 is arranged on the outer edge of the retainer 681 to spray lubricating oil toward the upper roller array 671 of the upper bearing. Since the upper bearing, side bearing, and lower bearing are arranged in this order from top to bottom in the annular groove, the lubricating oil supplied to the upper bearing flows through the side bearing and then the lower bearing.In this embodiment, the number of nozzles 174 is three, and they are arranged at approximately equal intervals around the circumference as shown in Fig. 5. The number of nozzles 174 is not limited to three, and may be two or more. If the turntable 31 rotates 360 degrees or more, the number of nozzles 174 may be one. Furthermore, at the start of work, the turntable 31 may be rotated by a required angle and lubricating oil may be supplied from the nozzles 174.

[0023] Between the second bearing member 55 below the lower roller array 672 and the cylindrical portion 60a, there is a gap 551. This gap 551 functions as a lubricant drop path and separates the second bearing member 55, which is a rotating member, from the cylindrical portion 60a, which is a stationary member. A groove-forming member 59 is disposed below the gap 551. As described above, the groove-forming member 59, together with the cylindrical portion 60a of the table body 60, forms a lubricant recovery groove 59a that collects the lubricant that has dropped from the second bearing member 55. A drain hole 59b is formed at the bottom of the lubricant recovery groove 59a to drain the lubricant that has accumulated in the lubricant recovery groove 59a. In this embodiment, there are two drain holes 59b, which are arranged at approximately equal intervals around the circumference of the lubricant recovery groove 59a, as shown in FIG. 5 . The number of drain holes 59b may be one or more. The drain hole 59b discharges the lubricating oil to the outside of the table main body 60 via a drain passage 60e formed in the cylindrical portion 60a. Lubricating oil has lower viscosity than grease, which improves the accuracy of phasing the rotary table 31. Furthermore, gravity causes the lubricating oil to flow smoothly in the order of the annular groove on the outer periphery of the second bearing member 55, the gap 551, the lubricating oil recovery groove 59a, the drain hole 59b, and the drain passage 60e.

[0024] Water-squeezing member 58 is disposed inside groove-forming member 59, with a small gap between it and exhaust path 581. Water-squeezing member 58 has water-squeezing shape 58a that protrudes downward toward lubricant recovery groove 59a. Water-squeezing shape 58a extends downward to a position lower than the height of exhaust path 581 on the lubricant recovery groove 59a side, and prevents lubricant that falls from lower roller row 672 through gap 551 into lubricant recovery groove 59a from reaching exhaust path 581.

[0025] 6 is an explanatory diagram showing the lubricating oil supplying device 200. The lubricating oil supplying device 200 includes a lubricating oil supply unit 210, a lubricating oil supply pipe 164, an air supply unit 165, an air piping 166, a solenoid valve 167, a check valve 168, an air supply pipe 169, a distributor 170, a lubricating oil supply pipe 171, a check valve 172, a nozzle piping 173, and a nozzle 174. A control unit 160 controls the operation of the rotary table device 30. A sequence circuit 161 is connected to the control unit 160 to operate each device of the rotary table device 30 according to instructions.

[0026] The lubricant supply unit 210 sends lubricant to the distributor 170 via the lubricant supply pipe 164. The lubricant supply unit 210 includes an oil tank 211, an oil level gauge 212, a filter 213, a lubricant pump 214, a motor 215, a relief valve 216, a lubricant supply pipe 217, a valve 218, a check valve 219, an oil pressure sensor 220, and an air filter 221. The oil tank 211 stores lubricant. The oil level gauge 212 measures the amount of lubricant in the oil tank 211. The lubricant pump 214 is driven by the motor 215 and draws up lubricant from the oil tank 211 and sends it to the valve 218 via the lubricant supply pipe 217. The filter 213 filters the drawn-up lubricant. The relief valve 216 is connected to the lubricating oil supply pipe 217 and is a safety valve that opens when the pressure of the lubricating oil in the lubricating oil supply pipe 217 becomes too high, releasing the lubricating oil into the oil tank 211 and reducing the pressure. The valve 218 opens in response to the pressure in the lubricating oil supply pipe 217 when the lubricating oil pump 214 sends lubricating oil. The check valve 219 is a check valve that maintains a constant oil pressure in the lubricating oil supply pipe 164 when the motor 215 is not operating. The oil pressure sensor 220 measures the pressure in the lubricating oil supply pipe 164 connected to the distributor 170. The air filter 221 prevents dust from entering the inside of the lubricating oil supply unit 210.

[0027] The distributor 170 measures the amount of lubricant delivered and distributes a fixed amount of lubricant to three lubricant supply pipes 171. A check valve 172 is provided downstream of each lubricant supply pipe 171, and nozzle pipes 173 connected to nozzles 174 are provided downstream of the check valves 172. When a predetermined amount of lubricant is distributed to the lubricant supply pipe 171, each nozzle pipe 173 downstream of the check valve 172 is filled with an amount of lubricant corresponding to the distributed amount.

[0028] The air supply device 165 includes an air pump 241, an air filter 242, an oil mist filter 243, and pressure gauges 244 and 245. The air supply device 165 passes dry air (hereinafter referred to as "air") supplied from the air pump 241 through the air filter 242 to remove dust contained in the air, and through the oil mist filter 243 to remove oil mist contained in the air, and supplies the air to the air piping 166. The pressure gauges 244 and 245 measure the pressure of the air after passing through the air filter 242 and the oil mist filter 243, respectively. The air piping 166 is provided with a solenoid valve 167 and a check valve 168. The solenoid valve 167 opens and closes in response to commands from the sequence circuit 161. An air supply pipe 169 is disposed downstream of the check valve 168. The air supply pipe 169 is connected to three nozzle pipes 173. The check valve 168 prevents the air containing the lubricating oil from flowing back from the air supply pipe 169 .

[0029] Next, the flow of lubricant will be described. Upon receiving a command from the control unit 160, the sequence circuit 161 temporarily drives the motor 215. The lubricant pump 214 driven by the motor 215 draws up lubricant from the oil tank 211 and sends it to the lubricant supply pipe 217. When the pressure in the lubricant supply pipe 217 increases, the valve 218 opens and the lubricant is sent to the distributor 170 via the lubricant supply pipe 164. A fixed amount of lubricant is measured by the distributor 170 and distributed to three lubricant supply pipes 171. The lubricant distributed to the three lubricant supply pipes 171 passes through a check valve 172 and fills the nozzle pipe 173.

[0030] At the timing when the lubricating oil moves to the nozzle pipe 173, the control unit 160 issues a command to the sequence circuit 161 to temporarily open the solenoid valve 167. The sequence circuit 161 temporarily opens the solenoid valve 167. The supply of air from the air pump 241 increases the pressure in the air pipe 166, and the air is supplied to the three nozzle pipes 173 via the air pipe 166 and the air supply pipe 169, increasing the pressure inside the nozzle pipes 173. This pushes the lubricating oil in the nozzle pipes 173 toward the nozzles 174. As a result, the lubricating oil is sprayed from the nozzles 174. Note that even if the pressure inside the nozzle pipe 173 increases, the lubricating oil does not flow back toward the lubricating oil supply pipe 171 because there is a check valve between the nozzle pipe 173 and the lubricating oil supply pipe 171.

[0031] 7 is an explanatory diagram showing the operation timing of the lubricating oil pump 214 and the air pump 241. The lubricating oil pump 214 operates every time tc to move the lubricating oil to the nozzle pipe 173. The time tc is, for example, about 10 to 20 minutes. The air pump 241 operates after a time td has elapsed since the lubricating oil pump 214 started operating. The time td is the time it takes for the lubricating oil to be sent to the nozzle pipe 173, and is about 5 to 10 seconds, although it depends on the length of the lubricating oil supply pipe 164.

[0032] As described above, according to this embodiment, the bearing device includes the first bearing member 67, which is a perforated disk having a substantially rectangular cross section when cut along a plane including the shaft; the second bearing member 55, which surrounds the first bearing member 67 on three sides (the upper side, the lower side, and the side of the central axis OB); and the upper roller array 671, the lower roller array 672, and the side roller array 673, which are respectively provided between the upper side, the lower side, the side of the central axis OB, and the second bearing member 55. The lubricant supplying device 200 includes a nozzle 174 that supplies lubricant to the upper roller array 671. As a result, the lubricant supplied to the upper roller array 671 by the nozzle 174 flows through the upper roller array 671, the side roller array 673, and the lower roller array 672 in this order, thereby supplying lubricant to all of the roller arrays. Furthermore, since there is no need to eliminate gaps between rotating components and non-rotating fixed components, an increase in sliding resistance can be prevented.

[0033] According to this embodiment, a lubricating oil recovery groove 59a is provided below the bearing device, and a drain hole 59b is provided for discharging the lubricating oil from the lubricating oil recovery groove 59a to the outside of the rotary table device 30. As a result, the lubricating oil can be recovered. Note that the drain hole 59b may not be provided.

[0034] According to this embodiment, there is provided a water-shedding shape 58a that separates the gap 551, which is the fall path for the lubricating oil to fall from the lower roller row 672, from the exhaust path 581 that runs from the lubricating oil recovery groove 59a to the motors 54, 66, making it difficult for the lubricating oil falling through the gap 551 to travel to the motors 54, 66 via the exhaust path 581.

[0035] According to this embodiment, the lubricant supplying device 200 includes a lubricant pump 214, a distributor 170 disposed downstream of the lubricant pump for supplying a constant amount of lubricant to the nozzle 174, an air pump 241, a solenoid valve 167 disposed downstream of the air pump 241 for turning on and off the air supply, an air supply pipe 169 connecting the distributor 170 and the nozzle 174 to the solenoid valve 167, and a control unit 160 that operates the lubricant pump 214 for a predetermined first time at predetermined time intervals and temporarily turns on the solenoid valve 167 after a predetermined second time has elapsed since the lubricant pump 214 was operated, thereby using air pressure to supply a constant amount of lubricant from the nozzle 174 to the upper roller array 671. As a result, an appropriate constant amount of lubricant can be supplied from the nozzle 174 to the upper roller array 671.

[0036] The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features of the embodiments corresponding to the technical features in each aspect described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted. [Explanation of symbols]

[0037] 10...5-axis machining center, 20...bed, 21...rail, 25...work table, 26...rail, 30...rotary table device, 31...rotary table, 40...center sleeve, 40a...flange, 40c...fluid flow path in sleeve, 51...first rotor, 51a...fluid flow path in rotor, 52...second rotor, 54...rotor magnet, 55...second bearing member, 55a...first member, 55b...second member, 56...first connecting portion, 56a...cylindrical portion, 56b...disk portion, 56c...hole, 57...second connecting portion, 58...water drain member, 58a...water Cut shape, 59...groove forming member, 59a...lubricant recovery groove, 59b...drain hole, 60...table body, 60a...cylindrical portion, 60b...disk portion, 60c...opening, 60d...fluid flow path inside housing, 60e...drain flow path, 61...center shaft, 61a...fixing portion, 62...encoder mounting portion, 62a...flange, 62b...center portion, 63...encoder, 63a...rotor portion, 63b...casing, 64...housing, 64a...recess, 64b...fluid flow path inside housing, 65...housing support portion, 66...stator coil, 67...second 1 bearing member, 68... O-ring, 69... fluid supply pipe, 70... turning spindle with built-in chuck device, 80... column, 81... rail, 90... saddle, 91... spindle, 100... work, 160... control unit, 161... sequence circuit, 164... lubricating oil supply pipe, 165... air supply device, 166... ​​air piping, 167... solenoid valve, 168... check valve, 169... air supply pipe, 170... distributor, 171... lubricating oil supply pipe, 172... check valve, 173... nozzle piping, 174... nozzle, 200... lubricating oil supply device, 21 0...Lubricant supply unit, 211...Oil tank, 212...Oil level gauge, 213...Filter, 214...Lubricant pump, 215...Motor, 216...Relief valve, 217...Lubricant supply pipe, 218...Valve, 219...Check valve, 220...Oil pressure sensor, 221...Air filter, 241...Air pump, 242...Air filter, 243...Oil mist filter, 244...Pressure gauge, 551...Gap, 581...Exhaust path, 671...Upper roller row, 672...Lower roller row, 673...Side roller row, 681...Retainer, 682...Retainer

Claims

1. A rotary table device, The table body and a rotary table that can rotate around a vertical central axis; a bearing device that supports the rotary table relative to the table body in vertical and radial directions; a motor that rotates the rotary table; a lubricant oil supply device that supplies lubricant oil to the bearing device; Equipped with The bearing device is a first bearing member attached to the table body and a second bearing member attached to the rotary table, wherein the first bearing member and the second bearing member are fitted with an inner diameter side of the first bearing member in an annular groove formed on an outer periphery of the second bearing member; an upper roller row, a lower roller row, and a side roller row are arranged on an upper surface, a lower surface, and a side surface of the first bearing member that face the second bearing member when fitted into the second bearing member, respectively; The lubricating oil supply device is a nozzle for supplying a predetermined amount of the lubricating oil to the upper roller row; a lubricating oil recovery groove below the bearing device; and a drain hole for discharging the lubricating oil from the lubricating oil recovery groove to the outside of the rotary table device, a drainer shape that separates a drop path through which the lubricating oil drops from the lower roller row from an exhaust path from the lubricating oil recovery groove to the motor; Rotating table device.

2. 2. The rotary table device according to claim 1, The lubricating oil supply device is A lubricating oil pump; a distributor disposed downstream of the lubricating oil pump and configured to supply a constant amount of the lubricating oil to the nozzle; An air pump and an electromagnetic valve provided downstream of the air pump for turning on and off the supply of air; an air supply pipe connecting the distributor and the nozzle to the solenoid valve; a control unit that operates the lubricating oil pump for a predetermined first time at predetermined time intervals, and temporarily turns on the solenoid valve after a predetermined second time has elapsed since the lubricating oil pump was operated, thereby using the air pressure to supply the constant amount of lubricating oil from the nozzle to the upper roller row; A rotary table device comprising:

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