Bearing lubrication system

Abstract

To dispense with piping for supplying lubricating oil in a circulating manner, and to simplify and miniaturize the structure.SOLUTION: A lubricating device 10 for a bearing 40 includes an oil tank 60 integrally rotating with a rotating shaft 30, and a through hole 55 provided in an insertion portion 29 of a pump casing 20. The oil tank 60 includes a bottom portion 62 disposed below the insertion portion 29 and attached to the rotating shaft 30, and an outer peripheral portion 69 protruding from an outer periphery of the bottom 62 to an upper side than the bearing 40 and surrounding the insertion portion 29. The through hole 55 is provided in the insertion portion 29 so as to be located at a position above the bearing 40 and below an upper end of the outer peripheral portion 69, and penetrates through the insertion portion 29 in a radial direction of the rotating shaft 30 so as to allow the flow of lubricating oil supplied from the inside of the oil tank 60. A straightening vane 56 for allowing the lubricating oil to flow from the outer side to the inner side within the oil tank 60 is provided in a lower end of the insertion portion 29.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a bearing lubrication device. [Background technology]

[0002] Patent Document 1 discloses a bearing lubrication device that supports a portion of a rotating shaft that protrudes from a pump casing to the outside. This lubrication device includes an oil receiver that surrounds the bearing, an oil chamber that surrounds the oil receiver, a discharge pipe that has one end located within the oil chamber and the other end located above the oil receiver, and an oil lifter that sends lubricating oil from the oil chamber to the discharge pipe, and circulates and supplies the lubricating oil from the oil chamber to the bearing. This lubrication device also includes an overflow pipe that returns excess lubricating oil supplied to the oil receiver through the discharge pipe to the oil chamber. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-46918 Summary of the Invention [Problem to be solved by the invention]

[0004] The lubrication device of Patent Document 1 requires piping and an oil lifter to circulate the lubricating oil to the bearings, and therefore has a complex and large structure. Therefore, there is room for improvement in simplifying the structure and reducing the size of the lubrication device of Patent Document 1.

[0005] An object of the present invention is to provide a bearing lubrication device that can circulate and supply lubricating oil without using piping, and that can be simplified in structure and made compact. [Means for solving the problem]

[0006] The present invention Bearing lubrication systemis a bearing lubrication device that is attached to a cylindrical insertion portion formed in a pump casing so as to surround a vertically extending rotating shaft and rotatably supports the rotating shaft, the device comprising: an oil tank that is disposed below the insertion portion and has a bottom portion attached to the rotating shaft; an outer periphery portion that protrudes from the outer periphery of the bottom portion to a position above the bearing and surrounds the insertion portion, the oil tank rotating integrally with the rotating shaft; and a through hole that is provided in the insertion portion so as to be located above the bearing and below an upper end of the outer periphery portion, passes through the insertion portion in the radial direction of the rotating shaft, and allows the flow of lubricating oil supplied from within the oil tank. A straightening vane that causes the lubricating oil to flow from the outside to the inside of the oil tank in the radial direction of the rotating shaft is provided at the lower end of the insertion portion. 。 The first aspect of the present invention further includes a vane provided on at least an outer surface of the bottom of the oil vat and configured to blow air from the inside to the outside in the radial direction of the rotating shaft, and a first cover attached to the pump casing and surrounding the vane and at least a part of the outer periphery of the oil vat. A bearing lubrication device is provided. In addition, a second aspect of the present invention provides a bearing lubrication device, wherein the outer circumferential portion of the oil tank further has a cylindrical window portion for checking the flow of the lubricating oil, a lower cylindrical portion below the window portion, an upper cylindrical portion above the window portion, and a connecting vane connecting the lower cylindrical portion and the upper cylindrical portion.

[0007] In this embodiment, when the oil tank rotates together with the rotating shaft by the operation of the pump, the lubricating oil also rotates together with the oil tank. At this time, since the flow speed (angular velocity) of the lubricating oil in the inner and outer parts of the oil tank in the radial direction of the rotating shaft is constant, the circumferential speed in the oil tank is faster on the outer side than on the inner side in the radial direction. At this time, the straightening vane provided at the lower end of the insertion part causes the lubricating oil on the radially outer side, which has a faster circumferential speed, to flow to the radially inner side, which has a slower circumferential speed. This causes the lubricating oil on the inner side to be pushed up and supplied to the bearing through the insertion part and the rotating shaft. Next, the lubricating oil that has passed through the bearing flows from the inside to the outside of the insertion part through a through hole provided on the upper side of the bearing, and then returns to the bottom side of the oil tank through the gap between the outer periphery of the oil tank and the insertion part.

[0008] In this manner, in this embodiment, an oil tank that rotates integrally with the rotating shaft is provided, and a through hole is provided in the insertion portion of the rotating shaft to return the lubricating oil that has passed through the bearing. Also, a flow straightening vane is provided to cause the lubricating oil to flow from the outside to the inside of the oil tank in the radial direction of the rotating shaft. This allows the lubricating oil to be circulated and supplied to the bearing without using piping or an oil lifter, which simplifies the structure of the lubrication device and makes it smaller. Effect of the Invention

[0009] In the present invention, the lubricating oil can be circulated and supplied without using piping, and the structure can be simplified and made compact. [Brief description of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view of a pump equipped with a bearing lubrication device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an enlarged cross-sectional view of part II in FIG. [Diagram 3] FIG. [Figure 4] Cross-sectional view of line III-III in Figure 2. [Diagram 5] Cross-sectional view taken along line IV-IV in Figure 2. [Figure 6] Cross-sectional view of line VV in Figure 2. [Figure 7] 5 is a cross-sectional view similar to FIG. 2, showing a bearing lubrication device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] (First embodiment) 1 shows a centrifugal pump 10 using a lubrication device 50 for a bearing 40 according to a first embodiment of the present invention. This centrifugal pump 10 is installed on an installation floor (not shown) of a pump facility, and sucks in water from a suction tank (not shown) and discharges it downstream.

[0013] First, the configuration of the centrifugal pump 10 will be described.

[0014] 1, the centrifugal pump 10 includes a pump casing 20, a rotating shaft 30 attached to the pump casing 20, and an impeller 35 attached to the rotating shaft 30. The centrifugal pump 10 also includes a ball bearing (bearing) 40 and a thrust bearing 45 on the upper side (outside) of the pump casing 20, which rotatably support the rotating shaft 30. The lubrication device 50 of this embodiment is attached to surround the ball bearing 40, and circulates and supplies lubricating oil to the ball bearing 40.

[0015] The pump casing 20 includes a suction bend 21 and a volute casing 22 attached to the upper side of the suction bend 21. The pump casing 20 also includes a base 24 attached to the upper side of the volute casing 22.

[0016] The suction bend 21 is a curved pipe that is curved so that pumped water flows from an inlet 21a at the lower end to an outlet 21b at the upper end from a horizontal direction upward in a vertical direction.

[0017] The volute casing 22 has a volute passage 23 that is shaped like a spiral and extends around the rotary shaft 30. An outlet section 22b including an outlet port is formed on the downstream side of the volute passage 23 in an outer wall 22a that defines the volute passage 23. A connection port 22c and an attachment port 22d are provided on the outer wall 22a. The connection port 22c spatially connects the connected suction bend 21 to the volute passage 23. The attachment port 22d is provided so as to be located directly above the connection port 22c and within the base 24, and allows the installation of an impeller 35 in the volute passage 23.

[0018] The base 24 includes a fixed seat 25, an outer peripheral wall 27, a cover wall 28, and an insertion portion 29, a ball bearing 40 is attached in the insertion portion 29, and a thrust bearing 45 is attached on the cover wall 28.

[0019] The fixed seat 25 is attached in a liquid-tight manner to the mounting opening 22d of the scroll casing 22. The fixed seat 25 is integrally provided with a protector 25a that supports the impeller 35. Referring to Fig. 2, the fixed seat 25 is formed with an insertion hole 25b through which the rotating shaft 30 is inserted. A mechanical seal 26 is attached between the insertion hole 25b and the rotating shaft 30 to prevent leakage of pumped water.

[0020] 2, the outer peripheral wall 27 includes a cylindrical lower portion 27a protruding upward from the outer periphery of the fixed seat 25, and a conical upper portion 27b attached to the upper end of the lower portion 27a. The upper portion 27b is provided with a plurality of radially penetrating openings 27c spaced apart in the circumferential direction.

[0021] The cover wall 28 is disk-shaped and is attached to the upper end of the upper portion 27b. An insertion hole 28a through which the rotating shaft 30 passes is formed in the cover wall 28. The diameter of the insertion hole 28a is larger than the diameter of the rotating shaft 30, and the gap therebetween is covered by a thrust bearing 45.

[0022] 2 and 3, the insertion portion 29 is cylindrical and extends vertically from the outer periphery of the insertion hole 28a toward the spiral casing 22, and surrounds a part of the rotating shaft 30. The insertion portion 29 has a flange portion 29a at its upper end for mounting to the cover wall 28. In this embodiment, the insertion portion 29 is cylindrical, but may be polygonal as long as it does not interfere with the flow of the lubricating oil described later.

[0023] 1, the rotating shaft 30 is disposed so as to pass through the insertion portion 29 and extend vertically relative to the pump casing 20. The rotating shaft 30 includes an inner portion 31 that passes through the fixed seat 25 and is disposed in the volute passage 23 (inside the pump casing 20), and an outer portion 32 that is disposed outside the pump casing 20. The upper end of the outer portion 32 passes through the base 24 and protrudes upward from the cover wall 28. A coupling 33 is attached to the upper end of the outer portion 32 for mechanically connecting an output shaft of an electric motor (drive portion) (not shown).

[0024] 1, the impeller 35 is attached to the lower end of the inner portion 31 (rotary shaft 30) and is disposed in the volute passage 23 through the attachment port 22d. When the rotary shaft 30 is rotated by the electric motor during operation of the centrifugal pump 10, the impeller 35 rotates integrally therewith. As a result, water in the suction sump is sucked in through the suction bend 21 and discharged from the discharge portion 22b through the volute passage 23.

[0025] The ball bearing 40 is a radial bearing (rolling bearing) and is attached in the insertion portion 29 of the base 24 (pump casing 20). However, a roller bearing may be used instead of the ball bearing 40, and the bearing in which the lubrication device 50 is disposed can be changed as necessary as long as it has a configuration capable of rotatably supporting the rotating shaft 30.

[0026] 2 and 4, the ball bearing 40 includes an inner ring 41 and an outer ring 42, both of which are circular, and a large number of spherical ball members 43. The inner ring 41 is attached to the rotating shaft 30 and rotates integrally with the rotating shaft 30 when the rotating shaft 30 rotates. The outer ring 42 is attached to the insertion portion 29 so as to face the inner ring 41 and does not rotate even when the rotating shaft 30 rotates. The ball members 43 are disposed between the inner ring 41 and the outer ring 42 so as to be able to roll freely. Between the outer peripheral surface of the inner ring 41 and the inner peripheral surface of the outer ring 42, there is a gap that is large enough to allow the flow of lubricating oil and prevent the ball members 43 from falling off.

[0027] Referring to FIG. 1, the thrust bearing 45 is attached on the cover wall 28 of the base 24, rotatably supports the upper end of the rotating shaft 30, and receives a force acting in the axial direction of the rotating shaft 30.

[0028] Next, the configuration of the lubricating device 50 will be specifically described.

[0029] 1, the lubrication device 50 is attached so as to surround the ball bearings 40, and circulates and supplies lubricating oil to the ball bearings 40 when the centrifugal pump 10 is in operation. Referring to Fig. 2, the lubrication device 50 includes the aforementioned insertion portion 29 provided in the pump casing 20, an oil tank 60 that surrounds the lower side of the insertion portion 29 from near the upper end thereof, and an air-cooling mechanism 70 for air-cooling the lubricating oil in the oil tank 60. Of these, the insertion portion 29 is a stationary member that does not rotate or move, and the oil tank 60 is a rotating member that rotates integrally with the rotating shaft 30.

[0030] 2, the insertion portion 29 is provided on the base 24 as described above, and the ball bearing 40 is attached below the center of the overall height. The insertion portion 29 is provided with a through hole 55 that allows the passage of lubricating oil and air, a flow straightening vane 56 that promotes the circulation of the lubricating oil, and a rib 58 that suppresses leakage of the lubricating oil.

[0031] 2 and 3, the through hole 55 is provided in the insertion portion 29, above the ball bearing 40 and below the upper end of the oil tank 60, and penetrates the insertion portion 29 in the radial direction. The through hole 55 is preferably provided in a middle region when the total height of the insertion portion 29 including the straightening vane 56 is divided into three equal parts, and is provided approximately in the center in this embodiment. Referring to FIG. 5, a plurality of through holes 55 (four in this embodiment) are provided at intervals in the circumferential direction of the insertion portion 29. The diameter of the through hole 55 is large enough to ensure a ventilation area for air without clogging with viscous lubricating oil.

[0032] 2 and 3, the flow straightening vane 56 is provided at the lower end of the insertion portion 29 via an annular end plate 57 extending in the radial direction of the rotary shaft 30. More specifically, the flow straightening vane 56 is provided integrally with the end plate 57, which is attached to the lower end of the insertion portion 29. Referring to Fig. 2, the inner diameter of the end plate 57 is larger than the outer diameter of the rotary shaft 30 and smaller than the inner diameter of the insertion portion 29. The outer diameter of the end plate 57 is larger than the outer diameter of the insertion portion 29 including the rib 58.

[0033] 6, the flow straightening vane 56 has an arc-shaped (semi-cylindrical) cross section that protrudes in the rotation direction R (counterclockwise) of the rotating shaft 30, and protrudes downward from an end plate 57 along the rotating shaft 30. In the radial direction of the rotating shaft 30, the flow straightening vane 56 causes the lubricating oil to flow from the outside to the inside of the oil tank 60.

[0034] 2 and 3, the rib 58 is a convex strip that protrudes radially outward from the outer surface of the insertion portion 29 and extends along the rotation shaft 30 from the end plate 57 to the same height as the upper end of the oil tank 60. Referring to Fig. 5, a plurality of ribs 58 (12 in this embodiment) are provided at intervals in the circumferential direction of the insertion portion 29 so as not to coincide with the angular position at which the through hole 55 is formed.

[0035] 2, the oil vat 60 is attached to the rotating shaft 30 and rotates integrally with the rotating shaft 30. The oil vat 60 includes a bottom 62 attached to the rotating shaft 30 and an outer peripheral portion 69 protruding upward from the outer periphery of the bottom 62. The upper end of the outer peripheral portion 69 is an opening that is open to the atmosphere. More specifically, as shown in FIGS. 2 and 3, the oil vat 60 is composed of a lower vat body 61 including the bottom 62, and an upper tubular member 64.

[0036] The vessel body 61 is made of a metal having good thermal conductivity (for example, copper or aluminum alloy), has a bottom 62 and a peripheral wall 63, and surrounds the end plate 57 and the flow straightening vanes 56.

[0037] The bottom portion 62 has an annular shape, is disposed below the lower end of the flow straightening vane 56 (insertion portion 29) with a gap therebetween, and covers and conceals the lower side of the insertion portion 29. A cylindrical mounting portion 62a is provided on the inner periphery of the bottom portion 62 for liquid-tight mounting to the rotating shaft 30. The outer diameter of the bottom portion 62 is larger than the outer diameter of the end plate 57.

[0038] The peripheral wall portion 63 is cylindrical, continues to the outer periphery of the bottom portion 62, and constitutes a part of the outer periphery 69. The peripheral wall portion 63 extends to the upper side of the end plate 57, and surrounds the end plate 57 including the lower end of the insertion portion 29 and the flow straightening vane 56. The inner diameter of the peripheral wall portion 63 is larger than the outer diameter of the end plate 57, and a gap is formed between the peripheral wall portion 63 and the end plate 57 that is large enough to allow the flow of lubricating oil and prevent interference between them.

[0039] 2, the inner surface of the tank body 61 facing the flow straightening vane 56 stores lubricating oil for lubricating the ball bearings 40. The outer surface of the tank body 61 opposite the flow straightening vane 56 is integrally provided with blades 71, which will be described later in detail.

[0040] The cylindrical member 64 is attached to the upper end of the tank body 61, and constitutes most of the outer circumferential portion 69. The cylindrical member 64 extends from near the lower end of the insertion portion 29 to above the through hole 55 (ball bearing 40), and surrounds the insertion portion 29. The inner diameter of the cylindrical member 64 is larger than the dimension from the axis of the rotating shaft 30 to the tip of the rib 58, and a gap is provided between the cylindrical member 64 and the insertion portion 29 to allow the flow of lubricating oil, and a gap is provided between the cylindrical member 64 and the rib 58 to prevent interference between them.

[0041] 2, the tubular member 64 of this embodiment includes a window portion 65 for checking the flow of lubricating oil, a lower tubular portion 66 below the window portion 65, and an upper tubular portion 67 above the window portion 65. The tubular member 64 also includes a connecting vane 68 for integrally forming the lower tubular portion 66 and the upper tubular portion 67. Of these, the portions other than the window portion 65 are made of a metal having good thermal conductivity (for example, copper or an aluminum alloy).

[0042] The window portion 65 is provided so as to be located radially outward of the rotating shaft 30 with respect to the through-hole 55. With reference to Figures 3 and 5, the window portion 65 is made of a transparent resin (e.g., acrylic resin) that allows the inside to be seen from the outside, and is formed into a cylindrical shape between the lower cylinder portion 66 and the upper cylinder portion 67 by outsert processing.

[0043] 2 and 3, the lower tube portion 66 extends from the window portion 65 to the upper end of the tank body 61. In other words, the lower tube portion 66 is cylindrical, has a flange portion 66a at its lower end for connecting to the upper end of the peripheral wall portion 63, and extends to the lower end of the through hole 55.

[0044] 2 and 3, the upper tube portion 67 extends upward from the window portion 65. More specifically, the upper tube portion 67 is cylindrical, and an upper end of the upper tube portion 67 is located below the flange portion 29a of the insertion portion 29 with a gap therebetween.

[0045] Of the tank body 61 and the tubular member 64 configured as above, the peripheral wall portion 63, the lower tubular portion 66, the window portion 65, and the upper tubular portion 67 form one outer circumferential portion 69.

[0046] 2 and 3, a labyrinth structure 67a is provided near the upper end of the outer circumferential portion 69 (upper cylindrical portion 67), i.e., above the through hole 55 of the oil tank 60. The labyrinth structure 67a is composed of a pair of annular grooves recessed radially outward from the inner circumferential surface of the upper cylindrical portion 67 in a semicircular cross section. This labyrinth structure 67a suppresses the upward flow (passage) of hydraulic oil by the surface tension of the attached hydraulic oil, and suppresses leakage of lubricating oil from the upper end of the upper cylindrical portion 67. On the other hand, the labyrinth structure 67a allows air that has flowed into the outer circumferential portion 69 from the upper end of the upper cylindrical portion 67 to pass toward the through hole 55.

[0047] Continuing to refer to FIGS. 2 and 3, the connecting vane 68 is provided by extending a specific guide vane 68a among a plurality of guide vanes 68a provided in the lower cylinder portion 66.

[0048] The guide vanes 68a protrude radially outward from the outer surface of the lower cylindrical portion 66, and extend along the rotation shaft 30 from the lower end to near the upper end of the lower cylindrical portion 66. With reference to Figures 3 and 4, a plurality of guide vanes 68a (24 in this embodiment) are provided at intervals in the circumferential direction of the lower cylindrical portion 66.

[0049] 3 and 5, the connecting vane 68 extends from the lower cylinder portion 66 across the window portion 65 to the upper cylinder portion 67, and protrudes radially outward from the outer surfaces of these portions. The protruding amount of the connecting vane 68 in the radial direction is smaller than the protruding amount of the guide vane 68a. In this embodiment, the connecting vane 68 protrudes integrally from the upper ends of four of the 24 equally spaced guide vanes 68a, which are positioned at 90 degree intervals. The connecting vane 68 including the guide vane 68a extends from the lower cylinder portion 66 to near the upper end of the upper cylinder portion 67.

[0050] It is not necessary to provide guide vanes 68a other than the specific guide vanes 68a that include the connecting vane 68. Also, the connecting vanes 68 and the guide vanes 68a may be provided separately. Also, if a plurality of windows 65 are provided intermittently at intervals in the circumferential direction and the lower cylindrical portion 66 and the upper cylindrical portion 67 are formed as an integral structure, it is not necessary to provide the connecting vane 68.

[0051] 2, the air-cooling mechanism 70 includes vanes 71 that rotate integrally with the rotation of the rotating shaft 30, and a vane cover 75 that surrounds the vanes 71 and the lower part of the outer periphery 69, and forcibly air-cools the lubricating oil in the oil tank 60. The vane cover 75 is attached to the base 24 (pump casing 20), and is a stationary member that neither rotates nor moves.

[0052] 2 and 3, a plurality of vanes 71 are provided radially on the outer surface of the tank body 61 (oil tank 60). When the centrifugal pump 10 is operated, the vanes 71 rotate integrally with the oil tank 60 and blow air from the inside to the outside in the radial direction of the rotating shaft 30.

[0053] Specifically, the blade 71 includes a first portion 72 provided on the bottom 62 of the oil vat 60, and a second portion 73 provided on the peripheral wall portion 63 (outer periphery 69). The first portion 72 protrudes downward from the bottom portion 62 and extends radially outward from the attachment portion 62a to the peripheral wall portion 63. The second portion 73 is continuous with the radial outer end of the first portion 72, and extends along the rotation shaft 30 to near the upper end of the peripheral wall portion 63.

[0054] 2 and 6, the blade cover 75 includes a first cover 76 that covers the outside of the blades 71, and a second cover 77 that further covers the outside of the first cover 76. In this embodiment, the first cover 76 and the second cover 77 are integrally provided via a plurality of connecting plates 78, and are attached to the base 24 via a bracket 79 protruding from the second cover 77. However, the first cover 76 and the second cover 77 may be provided separately and attached to the base 24 individually.

[0055] The first cover 76 includes a first bottom portion 76a disposed below the first portion 72 of the blade 71 with a gap therebetween, and a first outer peripheral portion 76b protruding upward from the outer periphery of the first bottom portion 76a.

[0056] The first bottom portion 76a is an annular plate that surrounds the rotating shaft 30. The inner diameter of the first bottom portion 76a is larger than the outer diameter of the rotating shaft 30, and a gap that allows air to pass therebetween is secured. The outer diameter of the first bottom portion 76a is larger than the dimension from the axis of the rotating shaft 30 to the radial outer end of the second portion 73 of the blade 71.

[0057] The first outer peripheral portion 76b is cylindrical and connected to the outer periphery of the first bottom portion 76a. The inner diameter of the first outer peripheral portion 76b is larger than the dimension from the axis of the rotating shaft 30 to the radial outer end of the second portion 73, and a gap that allows air to pass is secured between the first outer peripheral portion 76b and the peripheral wall portion 63. The upper end of the first outer peripheral portion 76b is disposed at a position equivalent to the upper end of the lower cylinder portion 66 of the oil vat 60 so that the window portion 65 can be seen from the outside of the base 24 through the opening 27c.

[0058] The second cover 77 has a second bottom portion 77a arranged at a distance below the first bottom portion 76a, and a second outer peripheral portion 77b protruding upward from the outer periphery of the second bottom portion 77a, and guides air outside the first cover 76 to the inner end side of the blades 71.

[0059] The second bottom portion 77a is an annular plate that surrounds the rotating shaft 30. The inner diameter of the second bottom portion 77a is larger than the outer diameter of the rotating shaft 30 and smaller than the inner diameter of the first bottom portion 76a. The outer diameter of the second bottom portion 77a is larger than the outer diameter of the first bottom portion 76a and smaller than the inner diameter of the lower portion 27a. A cylindrical insertion portion 77c that surrounds the rotating shaft 30 is provided on the inner periphery of the second bottom portion 77a.

[0060] The second outer peripheral portion 77b is cylindrical and connected to the outer periphery of the second bottom portion 77a. The inner diameter of the second outer peripheral portion 77b is larger than the outer diameter of the first outer peripheral portion 76b, and a gap is provided between them to allow air to pass through. The upper end of the second outer peripheral portion 77b is lower than the upper end of the first outer peripheral portion 76b, and is located at a height approximately half the total height of the first outer peripheral portion 76b.

[0061] The connecting plate 78 has an upper end connected to the first bottom portion 76a and a lower end connected to the second bottom portion 77a, and connects the first bottom portion 76a and the second bottom portion 77a. The connecting plates 78 extend in the radial direction of the rotating shaft 30 and are provided radially at intervals in the circumferential direction. When the centrifugal pump 10 is in operation, the connecting plate 78 functions as a straightening plate that straightens the air passing between the covers 76, 77 toward the inner ends of the blades 71.

[0062] The brackets 79 protrude radially outward from the second outer circumferential portion 77b, and a plurality of brackets 79 (six in this embodiment) are provided at intervals in the circumferential direction. The outer ends of the brackets 79 are mechanically connected to the lower portion 27a of the base 24. In this way, the entire blade cover 75 is attached to the base 24.

[0063] 2, an annular top plate 80 is provided on the upper end side of the insertion portion 29, against which the air blown out from the first cover 76 collides and is guided into the oil vat 60. The top plate 80 is attached to the underside of the flange portion 29a so as to be continuous with the insertion portion 29, and covers the opening at the upper end of the outer circumferential portion 69 with a gap therebetween that allows air to flow. The outer diameter of the top plate 80 is equal to the inner diameter of the first cover 76.

[0064] 2 and 3, a flange portion 29a of the insertion portion 29 located above the through hole 55 is provided with a plurality of (four in this embodiment) radially penetrating through holes 29b spaced apart in the circumferential direction. The diameter of the through holes 29b is large enough to allow air to pass through, and when the centrifugal pump 10 is in operation, the through holes 29b function as vent holes through which air that has passed between the oil tank 60 and the insertion portion 29 and through the through holes 55 flows out to the outside of the insertion portion 29. The diameter of the through holes 29b is large enough to allow an oil supply pipe 82 for refilling oil to be inserted, and when the centrifugal pump 10 is stopped, the through holes 29b function as an inlet for hydraulic oil.

[0065] Next, the flows of lubricating oil and air during operation of the centrifugal pump 10 will be described with reference to Fig. 2. In Fig. 2, the solid arrows indicate the flow of lubricating oil, and the dashed arrows indicate the flow of air.

[0066] First, when the centrifugal pump 10 is stopped, the lubricating oil is stored in the oil tank 60 up to the end plate 57. In addition, the inside of the base 24 in which the lubricating device 50 is arranged is in an atmospheric pressure state because it is connected to the outside through the opening 27c.

[0067] When the operation of the centrifugal pump 10 is started and the oil tank 60 rotates integrally with the rotating shaft 30, the lubricating oil also rotates in the same direction together with the oil tank 60. At this time, since the flow speed (angular velocity) of the lubricating oil in the inner and outer parts of the oil tank 60 in the radial direction of the rotating shaft 30 is constant, the circumferential speed in the oil tank 60 is faster on the outer side than on the inner side in the radial direction.

[0068] In this state, in the oil tank 60, the straightening vanes 56 cause the lubricating oil on the radially outer side, where the circumferential speed is high, to flow (be guided) toward the radially inner side, where the circumferential speed is low. As a result, the lubricating oil in the inner part of the oil tank 60 is pushed up and supplied to the ball bearing 40 through between the insertion part 29 and the rotating shaft 30. Next, the lubricating oil that has passed through the ball bearing 40 flows from the inside to the outside of the insertion part 29 through the through hole 55 provided on the upper side of the ball bearing 40.

[0069] Next, the lubricating oil that reaches between the outer periphery 69 of the oil tank 60 and the insertion part 29 returns to the bottom 62 of the oil tank 60 through the gap between them. At this time, the flow of the lubricating oil upward from the through hole 55 is prevented by air circulation, which will be described in detail later, and by the rib 58 provided on the insertion part 29, which suppresses the circumferential flow. Therefore, the lubricating oil flows toward the bottom 62 of the oil tank 60.

[0070] In this manner, the lubrication device 50 of the present embodiment can circulate and supply lubricating oil to the ball bearings 40 with a simple configuration, without using any special mechanisms such as piping or oil lifters.

[0071] On the other hand, when the oil vat 60 rotates due to the rotation of the rotating shaft 30, the vanes 71 rotate in the same direction. As a result, the air located on the rotating shaft 30 side is blown outward in the radial direction. The blown cooling air flows upward through a gap between the outer periphery 69 of the oil vat 60 and the first outer periphery 76b of the first cover 76. In addition, since the inner end side of the vanes 71 becomes negative pressure, the air inside the base 24 (outside the first cover 76) flows toward the rotating shaft 30 side through a gap between the first cover 76 and the second cover 77.

[0072] The cooling air passes between adjacent guide vanes 68a and connecting vanes 68, is discharged from the first cover 76, and collides with the top plate 80. Then, a portion of the air flows into the oil vat 60 from the upper end of the outer circumferential portion 69, and the remainder flows in a direction away from the oil vat 60.

[0073] The cooling air that has flowed into the oil tank 60 flows downward between the outer circumferential portion 69 and the insertion portion 29, and when it reaches the through hole 55, the circulating lubricating oil prevents it from flowing any further downward. As a result, it flows from the outside to the inside of the insertion portion 29 through the through hole 55, and since the lubricating oil also prevents it from flowing downward here, it flows upward between the insertion portion 29 and the rotating shaft 30. Then, when it reaches the upper end of the insertion portion 29, it flows out of the insertion portion 29 through the through hole 29b.

[0074] In this way, in the lubrication device 50 of this embodiment, the blades 71 rotating integrally with the rotating shaft 30 cause the cooling air to flow along the oil tank 60, thereby enabling the lubricating oil in the oil tank 60 to be forcibly air-cooled via the oil tank 60.

[0075] The lubricating device 50 configured in this manner has the following features.

[0076] An oil tank 60 that rotates integrally with the rotating shaft 30 is provided, and the insertion portion 29 of the rotating shaft 30 is provided with a through hole 55 for returning the lubricating oil that has passed through the ball bearing 40. Moreover, a straightening vane 56 for flowing the lubricating oil from the outside to the inside in the radial direction of the rotating shaft 30 within the oil tank 60 is provided at the lower end of the insertion portion 29. This allows the lubricating oil to be circulated and supplied to the ball bearing 40 without using piping or an oil lifter, so the structure of the lubrication device 50 can be simplified and made smaller.

[0077] A plurality of ribs 58 are provided on the outer periphery of the insertion portion 29. These ribs 58 can suppress the circumferential flow of the lubricating oil that has flowed through the through hole 55 to the outside of the insertion portion 29. As a result, the flow of the lubricating oil toward the upper end of the oil tank 60 can be suppressed, and therefore leakage of the lubricating oil from the upper end of the oil tank 60 can be suppressed.

[0078] Impellers 71 for blowing air are provided on the bottom 62 of the oil tank 60, and a first cover 76 surrounding the impellers 71 is attached to the pump casing 20. Therefore, the lubricating oil can be forcibly cooled through the oil tank 60 by the air flowing outside the oil tank 60. As a result, the lubricating oil can be maintained at a temperature lower than the allowable temperature, and therefore limitations on the operation time of the pump 10 can be substantially eliminated.

[0079] The blades 71 have a first portion 72 provided on the bottom portion 62 and a second portion 73 provided on the outer circumferential portion 69. This ensures a sufficient amount of airflow, thereby ensuring forced cooling of the lubricating oil.

[0080] A second cover 77 is attached to the pump casing 20 to guide the air outside the first cover 76 to the impeller 71. Therefore, the air is circulated to reliably forcibly cool the lubricating oil through the oil tank 60.

[0081] The first cover 76 has a first bottom 76a and a first outer circumferential portion 76b, and the second cover 77 has a second bottom 77a and a second outer circumferential portion 77b, and the first bottom 76a and the second bottom 77a are connected via a connecting plate 78. The air flowing toward the impellers 71 is rectified by the connecting plate 78, thereby promoting air circulation. In addition, the first cover 76 and the second cover 77 can be handled as a single unit, which improves workability during assembly or maintenance of the pump 10.

[0082] A top plate 80 is provided to guide the air blown out from the first cover 76 between the oil tank 60 and the insertion portion 29, and the insertion portion 29 is provided with a through hole (air vent) 29b through which the air that has passed through the through hole 55 flows out to the outside of the insertion portion 29. Therefore, the air circulating around the insertion portion 29 can suppress the upward flow of the lubricating oil that has passed through the through hole 55, so that leakage of the lubricating oil from the oil tank 60 can be effectively suppressed.

[0083] A labyrinth structure 67a that prevents the passage of lubricating oil while allowing air to pass through is provided above the through hole 55 of the oil tank 60. Therefore, even if the lubricating oil that has passed through the through hole 55 flows toward the upper end of the oil tank 60, leakage of the lubricating oil to the outside of the oil tank 60 can be prevented.

[0084] A window 65 is provided on the outer periphery 69 of the oil tank 60. This allows the circulation state of the lubricating oil in the oil tank 60 to be confirmed through the opening 27c and the window 65. If it is determined that the lubricating oil is insufficient, the lubricating oil can be replenished in the oil tank 60 by inserting an oil supply pipe 82 into a predetermined through hole 29b. As a result, it is possible to prevent the pump 10 from operating when the lubricating oil is insufficient.

[0085] In the oil tank 60, the window portion 65 is cylindrical, and a lower cylinder portion 66 below the window portion 65 and an upper cylinder portion 67 above the window portion 65 are connected by a connecting vane 68. Therefore, the circulation state of the lubricating oil in the rotating oil tank 60 during operation of the pump 10 can be easily confirmed through the cylindrical window portion 65. Moreover, the surface area of ​​the oil tank 60 is increased by the connecting vane 68, which improves the cooling efficiency of the lubricating oil.

[0086] A plurality of guide vanes 68a extending along the rotation shaft 30 are provided on the outer periphery 69 of the oil tank 60. The guide vanes 68a can increase the surface area of ​​the oil tank 60, thereby improving the cooling efficiency of the lubricating oil.

[0087] Other embodiments and various modifications of the present invention will be described below, but in these descriptions, points that are not particularly mentioned are the same as those in the first embodiment. In the drawings referred to below, the same elements as those in the first embodiment are given the same reference numerals.

[0088] Second embodiment 7 shows a lubrication device 50 according to a second embodiment. This lubrication device 50 differs from the lubrication device 50 according to the first embodiment in that a guide portion 80a that guides the cooling air blown by the blades 71 into the oil tank 60 is provided on the top plate 80.

[0089] The guide portion 80a is provided on the radially outer side of the top plate 80. The guide portion 80a is inclined downward from the radially inner side to the radially outer side. The outer periphery of the guide portion 80a is located radially outer than the first outer periphery 76b of the first cover 76.

[0090] The lubrication device 50 of the second embodiment configured in this manner can achieve the same actions and effects as those of the first embodiment. Moreover, most of the cooling air sent out from the first cover 76 can be guided into the oil vat 60 by the guide portion 80a. As a result, the amount of air that flows in and circulates between the outer periphery 69 of the oil vat 60 and the insertion portion 29 can be secured, so that leakage of the lubricating oil from the oil vat 60 can be reliably prevented.

[0091] The present invention is not limited to the configurations of the above-described embodiments, and various modifications are possible.

[0092] For example, the end plate 57 may not be provided, and the flow straightening vane 56 may be directly connected to the lower end of the insertion portion 29 .

[0093] The ribs 58 may not be provided on the outer periphery of the insertion portion 29. Alternatively, the air blown out by the blades 71 may not flow into the oil tank 60.

[0094] The blade 71 may be configured with only the first portion 72 protruding from the bottom portion 62 without providing the second portion 73 protruding from the peripheral wall portion 63 .

[0095] The blade cover 75 may be configured with only the first cover 76 without providing the second cover 77.

[0096] The oil tank 60 may not have the window portion 65. Also, the oil tank 60 may not have the labyrinth structure portion 67a.

[0097] The pump to which the lubrication device 50 for the bearing 40 is applied may be a vertical pump equipped with a straight lifting pipe, and the lubrication device 50 of the present invention can be applied to any pump equipped with a rotating shaft extending vertically and supported by a bearing, and similar actions and effects can be obtained. [Explanation of symbols]

[0098] 10. Centrifugal Pump 20 Pump casing 21 Suction bend 21a Inlet 21b Outlet 22 Spiral Casing 22a Outer wall 22b Discharge part 22c Connection port 22d Mounting port 23 Volute Passage 24 Pedestal 25 Fixed seat 25a Protector 25b Insertion hole 26 Mechanical seal 27 Outer wall 27a Lower part 27b Upper part 27c opening 28 Lid wall 28a Insertion hole 29 Insertion part 29a Flange 29b Through hole (vent hole) 30 Rotational Axis 31 Inner part 32 Outer part 33 Coupling 35 Impeller 40 Ball bearing (bearing) 41 Inner Circle 42 Outer ring 43 Ball component 45 Thrust bearing 50 Lubricating device 55 Through hole 56 Straightening vane 57 End plate 58 Ribs 60 Oil tank 61 Tank body 62 Bottom 62a Mounting part 63 Peripheral wall section 64 Cylinder Part 65 Window 66 Lower cylinder part 66a Flange part 67 Upper cylinder part 67a Labyrinth structure 68 Connecting vanes 68a Guide vane 69 Outer periphery 70 Air cooling mechanism 71 Feather 72 Part 1 73 Part 2 75 Feather Cover 76 1st Cover 76a 1st bottom 76b 1st outer periphery 77 2nd Cover 77a 2nd bottom 77b 2nd outer periphery 77c Insertion part 78 Connecting plate 79 Bracket 80 Tabletop 80a Guide part 82 Fuel Pipe

Claims

1. A bearing lubrication device that is attached to a cylindrical insertion portion formed in a pump casing so as to surround a rotating shaft extending in a vertical direction and rotatably supports the rotating shaft, comprising: an oil tank that is disposed below the insertion portion and has a bottom portion attached to the rotating shaft, and an outer periphery that protrudes from an outer periphery of the bottom portion to a position above the bearing and surrounds the insertion portion, and that rotates integrally with the rotating shaft; a through hole that is provided in the insertion portion so as to be located above the bearing and below an upper end of the outer circumferential portion of the oil tank, the through hole penetrating the insertion portion in the radial direction of the rotating shaft and allowing the flow of lubricating oil supplied from inside the oil tank; Equipped with A straightening vane is provided at a lower end of the insertion portion to cause the lubricating oil to flow from the outside to the inside of the oil tank in the radial direction of the rotating shaft, and further a blade provided on at least an outer surface of the bottom of the oil tank and configured to blow air from the inside to the outside in a radial direction of the rotating shaft; a first cover attached to the pump casing and surrounding the impeller and at least a portion of the outer periphery of the oil tank; A bearing lubrication device comprising:

2. 2. The bearing lubrication device according to claim 1, wherein a plurality of ribs extending along the rotation shaft are provided on an outer periphery of the insertion portion.

3. 3. The bearing lubrication device according to claim 1, wherein the vane has a first portion provided at the bottom of the oil tank and extending in the radial direction of the rotating shaft, and a second portion provided at the outer periphery of the oil tank and extending along the rotating shaft.

4. 4. The bearing lubrication device according to claim 1, further comprising a second cover attached to the pump casing for guiding air outside the first cover to the vanes.

5. the first cover has a first bottom portion disposed below the blade and a cylindrical first outer circumferential portion protruding upward from an outer periphery of the first bottom portion, the second cover has a second bottom portion disposed below the first bottom portion and a cylindrical second outer periphery portion protruding upward from an outer periphery of the second bottom portion, The first bottom portion and the second bottom portion are connected via a plurality of connecting plates extending in a radial direction of the rotating shaft.

5. A bearing lubricating device according to claim 4.

6. a top plate that is connected to the insertion portion, covers an upper end of the oil vat, and guides the air blown out from the first cover to a space between the oil vat and the insertion portion; an air vent provided in the insertion portion so as to be located above the through hole, through which the air that has passed through the through hole flows out to the outside of the insertion portion; A bearing lubrication device according to any one of claims 1 to 5, comprising:

7. 7. The bearing lubrication device according to claim 6, wherein a labyrinth structure portion that restricts passage of the lubricating oil while allowing passage of the air is provided in the oil tank above the through hole.

8. 8. The bearing lubrication device according to claim 1, wherein the outer periphery of the oil tank is provided with a window for checking the flow of the lubricating oil.

9. 9. The bearing lubrication device according to claim 8, wherein the outer circumferential portion of the oil tank has a cylindrical window portion, a lower cylindrical portion below the window portion, an upper cylindrical portion above the window portion, and a connecting vane connecting the lower cylindrical portion and the upper cylindrical portion.

10. A bearing lubrication device that is attached to a cylindrical insertion portion formed in a pump casing so as to surround a rotating shaft extending in a vertical direction and rotatably supports the rotating shaft, comprising: an oil tank that is disposed below the insertion portion and has a bottom portion attached to the rotating shaft, and an outer periphery that protrudes from an outer periphery of the bottom portion to a position above the bearing and surrounds the insertion portion, and that rotates integrally with the rotating shaft; a through hole that is provided in the insertion portion so as to be located above the bearing and below an upper end of the outer circumferential portion of the oil tank, the through hole penetrating the insertion portion in the radial direction of the rotating shaft and allowing the flow of lubricating oil supplied from inside the oil tank; Equipped with A straightening vane is provided at a lower end of the insertion portion to cause the lubricating oil to flow from the outside to the inside of the oil tank in the radial direction of the rotating shaft, and further A bearing lubrication device, wherein the outer periphery of the oil tank has a cylindrical window portion for checking the flow of the lubricating oil, a lower cylindrical portion below the window portion, an upper cylindrical portion above the window portion, and a connecting vane connecting the lower cylindrical portion and the upper cylindrical portion.

11. The bearing lubrication device according to claim 1 , wherein a plurality of plate-shaped guide vanes extending along the rotation shaft are provided on the outer periphery of the oil tank.

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