Centrifugal barrel polishing machine

Abstract

To maintain smooth rotation motion of a rotation shaft.SOLUTION: A centrifugal barrel polishing machine 10 comprises: a turret 11 that rotates about a sun shaft 12; a barrel tank 13 provided at an eccentric position of the turret 11 so as to be relatively rotatable and planetary-rotated; a cylindrical support member 15 fixed to the turret 11 and surrounding a rotation shaft 14 integrally rotated with the barrel tank 13; a first bearing 21 and a second bearing 22 arranged in the cylindrical support member 15 so as to support the rotation shaft 14; a first inlet 35 and a second inlet 47 arranged on an outer peripheral surface of the cylindrical support member 15 so as to inject lubricants into the first bearing 21 and the second bearing 22; and a first outlet 42 and a second outlet 52 arranged on the outer peripheral surface of the cylindrical support member 15 so as to discharge the lubricants in the cylindrical support member 15. The first outlet 42 and the second outlet 52 are arranged in a region closer to an outer peripheral edge 11E of the turret 11 than an axial center 14A of the rotation shaft 14.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a centrifugal barrel finishing machine. [Background technology]

[0002] Patent Document 1 discloses a centrifugal barrel finishing machine that performs polishing by planetary rotation of a barrel tub around a vertical sun axis and a rotation axis. The centrifugal barrel finishing machine has a revolutionary turret that rotates around the sun axis and a barrel tub that rotates integrally with the rotation axis at an eccentric position of the revolutionary turret. In this type of centrifugal barrel finishing machine, the rotation axis is supported by a rolling bearing. The rolling bearing has an inner ring that rotates integrally with the rotation axis, an outer ring that is fixed relative to the revolutionary turret, multiple rolling elements disposed between the inner ring and the outer ring, and a ring-shaped cage that supports the multiple rolling elements. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-239892 Summary of the Invention [Problem to be solved by the invention]

[0004] In rolling bearings, the rolling elements come into rolling contact with the inner and outer rings, so the frictional resistance between the components that make up the rolling bearing and the wear of each component are less than in sliding bearings, but a lubricant is still supplied to rolling bearings to maintain smooth rotation of the rotating shaft.However, as the components wear out with the rotation of the rotating shaft, the amount of wear powder mixed into the lubricant increases, and the lubricating function of the lubricant deteriorates.

[0005] The present invention was completed in view of the above circumstances, and an object of the present invention is to maintain smooth rotation of the rotation shaft. [Means for solving the problem]

[0006] The present disclosure provides: a turret that rotates around the sun axis; a barrel tank that is provided at an eccentric position of the turret so as to be rotatable relative to the turret and rotates in a planetary fashion; a cylindrical support member fixed to the turret and surrounding a rotation shaft that rotates integrally with the barrel tank; a bearing disposed inside the cylindrical support member and supporting the rotation shaft so that the rotation shaft can rotate relative to the cylindrical support member; an injection port disposed on an outer peripheral surface of the cylindrical support member for injecting a lubricant into the bearing; a discharge port disposed on the outer circumferential surface of the cylindrical support member for discharging the lubricant inside the cylindrical support member, The discharge port is disposed in a region closer to the outer periphery of the turret than to the axis of the rotation shaft. [Effects of the Invention]

[0007] According to the present disclosure, smooth rotation of the rotation axis can be maintained. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view of the centrifugal barrel finishing machine of Example 1, with the barrel tanks omitted. [Figure 2] FIG. 2 is a cross-sectional view showing a bearing structure of a centrifugal barrel finishing machine. DETAILED DESCRIPTION OF THE INVENTION

[0009] First, embodiments of the present disclosure will be listed and described. Any combination of the following multiple embodiments within a range that does not cause contradictions is also included in the description of the present invention. The centrifugal barrel finishing machine of the present disclosure comprises: (1) A device comprising: a turret that rotates around the sun axis; a barrel tank that is rotatable relative to the turret at an eccentric position and rotates in a planetary manner; a cylindrical support member that is fixed to the turret and surrounds a rotation axis that rotates integrally with the barrel tank; a bearing that is disposed inside the cylindrical support member and supports the rotation axis so that it can rotate relative to the cylindrical support member; an inlet that is disposed on the outer surface of the cylindrical support member and is used to inject lubricant into the bearing; and an outlet that is disposed on the outer surface of the cylindrical support member and is used to discharge the lubricant from inside the cylindrical support member, wherein the outlet is disposed in an area closer to the outer periphery of the turret than to the axis of the rotation axis.

[0010] The cylindrical support member fixed to the turret revolves integrally with the turret around the sun axis. Wear debris generated by the components of the rolling bearing and mixed into the lubricant is concentrated in a region inside the cylindrical support member near the outer periphery of the turret due to centrifugal force centered on the sun axis. Focusing on this point, the present disclosure positions the discharge port in a region of the outer periphery of the cylindrical support member closer to the outer periphery of the turret than the axis of the rotation axis, i.e., in the same region as the region where wear debris concentrates in the circumferential direction. Therefore, according to the present disclosure, the portion of the lubricant containing a large amount of wear debris can be efficiently discharged to the outside of the bearing.

[0011] (2) The inlet is preferably located in a region closer to the sun axis than the axis of the rotation shaft. According to this configuration, the inlet and outlet are located on opposite sides of the axis of the rotation shaft in the direction of the centrifugal force lines. This arrangement allows the direction in which new lubricant pushes old lubricant in a plan view to be the overall direction from the inlet to the outlet, thereby reducing the amount of remaining old lubricant. This prevents the lubricating function of the lubricant from deteriorating, maintaining smooth rotation of the rotation shaft.

[0012] (3) In (1) or (2), it is preferable that the inlet and the outlet are arranged at different positions on either side of the bearing in the axial direction of the rotation shaft. With this configuration, the direction in which the new lubricant pushes the old lubricant is the direction from the inlet to the outlet, so that the amount of remaining old lubricant can be reduced.

[0013] (4) In (3), it is preferable that the sun shaft and the rotation shaft are arranged with their axes oriented vertically, and the inlet is arranged above the outlet. With this configuration, lubricant containing a large amount of wear powder can be efficiently discharged.

[0014] (5) In (1) or (2), the sun shaft and the rotation shaft are arranged with their axes oriented vertically, the plurality of bearings are arranged at intervals in the axial direction of the rotation shaft, an oil seal is arranged below the lowest bearing to seal the gap between the rotation shaft and the cylindrical support member, and a closure plate is arranged above the oil seal to liquid-tightly close the gap between the lowest bearing and the oil seal. With this configuration, the oil seal can prevent foreign matter from entering the cylindrical support member from the outside. The closure plate can prevent lubricant that lubricates the lowest bearing from leaking toward the oil seal.

[0015] (6) In (1) or (2), the bearing preferably comprises an outer ring, an inner ring, a plurality of rolling elements arranged to be able to roll between the outer ring and the inner ring, and a cage that holds the plurality of rolling elements in a state in which they are positioned circumferentially, the outer ring, the inner ring, and the rolling elements being made of metal, and the cage being made of synthetic resin. This configuration makes it possible to suppress the generation of wear powder.

[0016] Example 1 A first embodiment of the present disclosure will be described below with reference to Figures 1 and 2. In the following description, the up and down directions are defined as those shown in Figure 2. The up and down directions and the vertical direction are used synonymously. Figure 1 is a cross-sectional view taken at the height of line XX in Figure 2.

[0017] The centrifugal barrel finishing machine 10 of the present embodiment 1 has a turret 11 and a plurality of (four in the present embodiment 1) barrel tanks 13, and is an apparatus for polishing workpieces (not shown) in the barrel tanks 13 by planetary rotation of the barrel tanks 13.

[0018] The turret 11 rotates integrally with a sun shaft 12, whose axis is oriented vertically (up and down). The sun shaft 12 is rotationally driven by a revolution motor (not shown). In a plan view of the centrifugal barrel finishing machine 10 seen from above, the multiple barrel tanks 13 are arranged at eccentric positions on the turret 11 (positions radially outwardly shifted from the sun shaft 12). The multiple barrel tanks 13 are arranged at equal angular intervals in the circumferential direction on the circumference of a virtual circle concentric with the sun shaft 12. The barrel tanks 13 are integral with a rotation shaft 14, whose axis is oriented vertically (parallel to the sun shaft 12), and are rotatable relative to the turret 11. The barrel tanks 13 revolve integrally with the turret 11 and rotate relative to the turret 11 (spinning on their own axes), thereby performing planetary rotation.

[0019] Next, the support structure for the rotation shafts 14 will be described. Cylindrical support members 15 that individually support each rotation shaft 14 are fixed to the turret 11. The cylindrical support member 15 is a member made up of an assembly of multiple parts, and has a cylindrical shape with its axis oriented vertically as a whole. The upper end of the cylindrical support member 15 is fixed in a state where it is fitted into a through-hole 16 of the turret 11. The portion of the cylindrical support member 15 other than the upper end protrudes downward from the underside of the turret 11.

[0020] The barrel tank 13 is located above the turret 11 and the cylindrical support member 15. The rotation shaft 14 is fixed to the barrel tank 13 with its upper end surface in surface contact with the bottom surface of the barrel tank 13. The rotation shaft 14 protrudes downward from the barrel tank 13 and is coaxially housed in the cylindrical support member 15. The lower end of the rotation shaft 14 protrudes downward from the lower end surface of the cylindrical support member 15. A pulley 17 is attached to the lower end of the rotation shaft 14 so that they can rotate integrally. A belt (not shown) is stretched between the pulley 17 and a rotation motor (not shown), and the rotation shaft 14 and the barrel tank 13 are rotated by the rotation motor.

[0021] The rotation shaft 14 is supported so as to pass through the turret 11. The rotation shaft 14 is rotatably supported by two first bearings 21 and one second bearing 22 provided in a cylindrical support member 15. The first bearing 21 and the second bearing 22 are members of the same structure, and are configured to include a metal outer ring 23, a metal inner ring 24, a plurality of metal rolling elements 25, and a cage 26 made of synthetic resin.

[0022] The outer ring 23 is annular and fixed to the cylindrical support member 15. The inner ring 24 is annular and can rotate integrally with the rotation shaft 14. The rolling elements 25 are cylindrical and housed in the gap between the outer ring 23 and the inner ring 24. The cage 26 is annular and holds the rolling elements 25 so that they are spaced apart in the circumferential direction. When the rotation shaft 14 rotates, the inner ring 24 rotates relative to the outer ring 23, and the rolling elements 25 roll while in contact with the inner circumferential surface of the outer ring 23 and the outer circumferential surface of the inner ring 24. A lubricant (not shown) is injected into the cylindrical support member 15. By filling the first bearing 21 and the second bearing 22 with lubricant, frictional resistance between the outer ring 23 and the rolling elements 25 and frictional resistance between the inner ring 24 and the rolling elements 25 are reduced.

[0023] The two first bearings 21 are arranged adjacent to each other in the vertical direction at the upper end of the cylindrical support member 15. The area excluding the lower end of the upper first bearing 21 and the lower end of the lower first bearing 21 is located within the thickness of the turret 11 in the vertical direction. The second bearing 22 is arranged at the lower end of the cylindrical support member 15.

[0024] A first oil seal 28 is disposed above the upper first bearing 21. The first oil seal 28 functions to prevent foreign matter from entering the cylindrical support member 15 from above the gap between the outer circumferential surface of the rotation shaft 14 and the inner circumferential surface of the cylindrical support member 15. A cylindrical spacer 29 is disposed between the lower surface of the lower first bearing 21 and the upper surface of the second bearing 22. The spacer 29 rotates integrally with the rotation shaft 14. A ring-shaped leakage prevention member 30 is disposed between the outer circumferential surface of the spacer 29 and the inner circumferential surface of the cylindrical support member 15. The leakage prevention member 30 prevents the lubricant filled in the first bearing 21 from leaking downward.

[0025] Two second oil seals 31 are arranged adjacent to each other above and below below the second bearing 22. The second oil seals 31 are arranged between the outer peripheral surface of the rotation shaft 14 and the inner peripheral surface of the cylindrical support member 15 and are components that provide a liquid-tight seal between the interior and exterior of the cylindrical support member 15. The second oil seals 31 prevent foreign matter from entering the cylindrical support member 15 from below the gap between the outer peripheral surface of the rotation shaft 14 and the inner peripheral surface of the cylindrical support member 15. A metal closure plate 32 is arranged above the second oil seals 31 to provide a liquid-tight seal between the second bearing 22 and the second oil seals 31. The closure plate 32 is a component that prevents lubricant from flowing between the second bearing 22 side and the second oil seals 31 side within the cylindrical support member 15.

[0026] The cylindrical support member 15 is provided with a first injection path 33 for supplying lubricant to the first bearing 21, and a first discharge path 40 for discharging the lubricant filled in the first bearing 21. The first injection path 33 has one first annular injection space 34, one first injection inlet 35, and one first injection hole 36. The first annular injection space 34 is an annular space secured above the upper first bearing 21 between the outer circumferential surface of the rotation shaft 14 and the inner circumferential surface of the cylindrical support member 15. The first injection inlet 35 opens to the outer circumferential surface of the cylindrical support member 15.

[0027] In a plan view, two intersection points 38, 39 are set on the outer peripheral surface of the cylindrical support member 15, where an imaginary line L passing through the axis 12A of the sun axis 12 and the axis 14A of the rotation axis 14 intersects. The imaginary line L is a line along the force line of the centrifugal force generated on the rotation axis 14 by the revolution around the sun axis 12. Of the two intersection points, the one on the side closer to the sun axis 12 than the axis 14A of the rotation axis 14 is defined as the inner intersection point 38. Of the two intersection points 38, 39, the one on the side closer to the outer peripheral edge 11E of the turret 11 (the side farther from the sun axis 12) than the axis 14A of the rotation axis 14 is defined as the outer intersection point 39.

[0028] In plan view, first injection port 35 opens to a region including inner intersection 38. First injection hole 36 is a passage that linearly connects first annular injection space 34 and first injection port 35. In plan view, first injection hole 36 extends radially from axis 14A of rotation shaft 14 to first injection port 35. First injection port 35 and first annular injection space 34 are located at the same height in the vertical direction, and first injection hole 36 extends horizontally.

[0029] The first discharge path 40 has one first annular discharge space 41, one first discharge port 42, and one first discharge hole 43. The first annular discharge space 41 is an annular space secured between the outer peripheral surface of the spacer 29 and the inner peripheral surface of the cylindrical support member 15, at a height below the lower first bearing 21 and above the leakage prevention member 30.

[0030] The first discharge port 42 opens to the outer peripheral surface of the cylindrical support member 15. In plan view, the first discharge port 42 opens to a region including the outer intersection point 39 on the outer peripheral surface of the cylindrical support member 15. The first discharge hole 43 is a passage that linearly connects the first annular discharge space 41 and the first discharge port 42. In plan view, the first discharge hole 43 extends radially along an imaginary line L that passes through the axis 12A of the sun shaft 12 and the axis 14A of the rotation shaft 14. The first discharge port 42 and the first annular discharge space 41 are located at the same height in the vertical direction, and the first discharge hole 43 extends horizontally.

[0031] A second injection path 45 for supplying lubricant to the second bearing 22 and a second discharge path 50 for discharging the lubricant filled in the second bearing 22 are provided within the cylindrical support member 15. The second injection path 45 has one second annular injection space 46, one second injection port 47, and one second injection hole 48. The second annular injection space 46 is disposed above the second bearing 22 and at a height below the leakage prevention member 30 (same height as the lower end of the spacer 29). The second annular injection space 46 is disposed between the rotation shaft 14 and the cylindrical support member 15 in the radial direction centered on the rotation shaft 14, and is an annular space secured between the outer peripheral surface of the spacer 29 and the inner peripheral surface of the cylindrical support member 15. The second injection port 47 opens to the outer peripheral surface of the cylindrical support member 15.

[0032] Similar to first injection port 35, second injection port 47 opens to a region including inner intersection 38 in plan view. Second injection hole 48 is a passage that linearly connects second annular injection space 46 and second injection port 47. In plan view, second injection hole 48 extends radially from axis 14A of rotation shaft 14 to second injection port 47. Second injection port 47 and second annular injection space 46 are located at the same height in the vertical direction, and second injection hole 48 extends horizontally.

[0033] The second discharge path 50 has one second annular discharge space 51, one second discharge port 52, and one second discharge hole 53. The second annular discharge space 51 is an annular space secured below the second bearing 22 between the lower end of the outer circumferential surface of the second bearing 22 and the inner circumferential surface of the cylindrical support member 15.

[0034] The second discharge port 52 opens to the outer peripheral surface of the cylindrical support member 15. Like the first discharge port 42, the second discharge port 52 opens to a region including the outer intersection 39 in a plan view. The second discharge hole 53 is a passage that linearly connects the second annular discharge space 51 and the second discharge port 52. In a plan view, the second discharge hole 53 extends radially along an imaginary line L that passes through the axis 12A of the sun shaft 12 and the axis 14A of the rotation shaft 14. The second discharge port 52 and the second annular discharge space 51 are located at the same height in the vertical direction, and the first discharge hole 43 extends horizontally.

[0035] When barrel polishing is performed using the centrifugal barrel polishing machine 10 of the present embodiment 1, the workpieces to be polished and polishing stones (not shown) for polishing the workpieces are placed in the barrel tank 13. In the polishing process, the mass (workpieces and polishing stones) flows within the planetary rotating barrel tank 13, whereby the workpieces are polished by the polishing stones.

[0036] When the barrel tub 13 is in planetary rotation, the rotating shaft 14 and the inner ring 24 rotate integrally relative to the cylindrical support member 15 and the outer ring 23, and the rolling elements 25 rotate while contacting the inner ring 24 and the outer ring 23. While the rotating shaft 14 is rotating, the outer ring 23, the inner ring 24, and the rolling elements 25 constituting the first bearing 21 and the second bearing 22 come into contact with each other, generating wear powder from these metal members 23, 24, and 25. This wear powder is mixed into the lubricant.

[0037] The outer ring 23 and cylindrical support member 15 revolve around the sun axis 12, but do not rotate (spin) relative to the turret 11. Therefore, as the polishing process progresses, wear debris generated from the outer ring 23, inner ring 24, and rolling elements 25 and mixed into the lubricant is caused by the centrifugal force generated by the revolution to collect in an area of ​​the outer ring 23 and cylindrical support member 15 closer to the outer peripheral edge 11E of the turret 11 than the axis 14A of the rotation axis 14 (an area on the opposite side from the sun axis 12 in plan view). Furthermore, because the wear debris is made of metal, which has a higher specific gravity than the synthetic oil lubricant, it is collected downward by gravity.

[0038] The amount of wear debris generated from the first bearing 21 and the second bearing 22 increases as the polishing time increases, and as the amount of wear debris mixed into the lubricant increases, the lubricating function of the lubricant decreases. Therefore, to maintain the lubricating function, the lubricant in the cylindrical support member 15 is replaced. The lubricant is replaced by injecting new pressurized lubricant into the cylindrical support member 15 from the first inlet 35 and the second inlet 47 through the first injection path 33 and the second injection path 45, and then discharging the old lubricant through the first discharge path 40 and the second discharge path 50 and the first discharge port 42 and the second discharge port 52.

[0039] More specifically, new lubricant injected through the first injection port 35 flows into the first annular injection space 34 through the first injection hole 36, and fills the upper first bearing 21, the lower first bearing 21, the first annular discharge space 41, and the first discharge hole 43. During this time, the old lubricant in the first injection hole 36, the first annular injection space 34, the upper first bearing 21, the lower first bearing 21, the first annular discharge space 41, and the first discharge hole 43 is pushed by the new lubricant and discharged from the first discharge port 42.

[0040] Furthermore, new lubricant injected through the second injection port 47 flows into the second annular injection space 46 through the second injection hole 48, and fills the second bearing 22, the second annular discharge space 51, and the second discharge hole 53. During this time, the old lubricant in the second injection hole 48, the second annular injection space 46, the second bearing 22, the second annular discharge space 51, and the second discharge hole 53 is pushed by the new lubricant and discharged from the second discharge port 52.

[0041] In the replacement process, the direction in which the new lubricant and the old lubricant move from the first inlet 35 to the first outlet 42 and the direction in which they move from the second inlet 47 to the second outlet 52 are, in plan view, directions from the sun axis 12 toward the outer peripheral edge 11E of the turret 11 (direction in which centrifugal force due to revolution acts). These movement directions are directions toward regions of the outer ring 23 and the cylindrical support member 15 where a large amount of wear debris accumulates due to centrifugal force (regions close to the outer peripheral edge 11E of the turret 11).

[0042] In the vertical direction, the direction in which the new lubricant and the old lubricant move from the first inlet 35 toward the first outlet 42 and the direction in which they move from the second inlet 47 toward the second outlet 52 during replacement are the same direction as gravity, that is, toward the area where a large amount of wear powder accumulates due to gravity. Therefore, the old lubricant can be efficiently discharged. Even if the replacement rate of the old lubricant and the new lubricant is not 100% and some of the old lubricant remains in the cylindrical support member 15, at least the lubricant with a large amount of wear powder can be reliably discharged.

[0043] Furthermore, during polishing, centrifugal force acts on the barrel tank 13 about the rotation shaft 14 due to the flow of mass, causing vibrations in the barrel tank 13 and the rotation shaft 14 that tilt the axis of the rotation shaft 14. A cylindrical support member 15 that supports the rotation shaft 14 is fixed at its upper end to the turret 11. The portion of the cylindrical support member 15 below the turret 11 extends in a cantilevered manner, and the lower end of the cylindrical support member 15 is a free end. Therefore, the barrel tank 13 and the rotation shaft 14 vibrate so as to tilt around a fixed portion 15F of the cylindrical support member 15 that is fitted into the through-hole 16 of the turret 11 as a fulcrum.

[0044] As the rotation shaft 14 tilts, the portion of the cylindrical support member 15 on the free end side (the portion below the turret 11) deforms in accordance with the tilt of the rotation shaft 14. Therefore, the second bearing 22, which is disposed in the region on the free end side of the cylindrical support member 15, is subjected to a small radial load caused by the tilt of the rotation shaft 14. In other words, the frictional resistance between the rolling element 25 and the outer ring 23 and between the rolling element 25 and the inner ring 24 is small.

[0045] In contrast, the fixed portion 15F of the cylindrical support member 15 to the turret 11 is fitted to the turret 11 and therefore does not deform, or even if it does, the amount of deformation is smaller than that of the free end side. Therefore, the radial load caused by the tilt of the rotation axis 14 is larger in the first bearing 21 than in the second bearing 22, raising concerns about increased frictional resistance between the rolling element 25 and the outer ring 23 and between the rolling element 25 and the inner ring 24. As a countermeasure, two first bearings 21 are arranged adjacent to each other in the axial direction and are disposed vertically within the region of the fixed portion 15F of the cylindrical support member 15 (the portion that fits to the turret 11). This reduces the load acting on each first bearing 21, thereby reducing the frictional resistance between the rolling element 25 and the outer ring 23 and between the rolling element 25 and the inner ring 24, and ultimately reducing the amount of wear debris generated by the first bearing 21.

[0046] The centrifugal barrel finishing machine 10 of the present disclosure includes a turret 11 that rotates around a sun axis 12, a barrel tub 13, and a cylindrical support member 15. The barrel tub 13 is rotatably mounted at an eccentric position on the turret 11 and rotates in a planetary fashion. The cylindrical support member 15 is fixed to the turret 11 and surrounds a rotation shaft 14 that rotates integrally with the barrel tub 13. A first bearing 21 and a second bearing 22 are disposed inside the cylindrical support member 15 to support the rotation shaft 14 so that it can rotate relative to the cylindrical support member 15. A first inlet 35 and a second inlet 47 are disposed on the outer circumferential surface of the cylindrical support member 15 for injecting lubricant into the first bearing 21 and the second bearing 22. A first outlet 42 and a second outlet 52 are disposed on the outer circumferential surface of the cylindrical support member 15 for discharging the lubricant from the cylindrical support member 15. The first discharge port 42 and the second discharge port 52 are arranged in an area closer to the outer circumferential edge 11E of the turret 11 than to the axis 14A of the rotation shaft 14.

[0047] The cylindrical support member 15 and the outer rings 23 of the first bearing 21 and second bearing 22, which are fixed to the turret 11, revolve integrally with the turret 11 around the sun shaft 12. The cylindrical support member 15 does not rotate (spin) relative to the turret 11. Wear powder generated from the components of the first bearing 21 and the second bearing 22 (the outer ring 23, inner ring 24, and rolling elements 25) and mixed into the lubricant is collected by centrifugal force centered on the sun shaft 12 in a region inside the cylindrical support member 15 (the first bearing 21 and the second bearing 22) close to the outer peripheral edge 11E of the turret 11. The region where the wear powder collects is a region on the opposite side of the center of the cylindrical support member 15 and the axis 14A1 of the rotation shaft 14 from the sun shaft 12 in a plan view.

[0048] In light of this, in the first embodiment, the first discharge port 42 and the second discharge port 52 are located in a region of the outer circumferential surface of the cylindrical support member 15 that is closer to the outer circumferential edge 11E of the turret 11 than the axis 14A of the rotation shaft 14, i.e., in the same region where wear debris concentrates in the circumferential direction. Therefore, with the centrifugal barrel finishing machine 10 of the first embodiment, during maintenance, portions of the lubricant containing a large amount of wear debris can be efficiently discharged to the outside of the first bearing 21 and the second bearing 22. This prevents a decrease in the lubricating function of the lubricant and maintains smooth rotation of the rotation shaft 14. If the amount of wear debris remaining in the cylindrical support member 15 after maintenance is small, smooth rotation of the rotation shaft can be maintained for a long period of time.

[0049] The first inlet 35 and the second inlet 47 are arranged in a region closer to the sun axis 12 than the axis 14A of the rotation shaft 14. With this configuration, the first inlet 35 and the first outlet 42 are arranged in regions opposite each other across the axis 14A of the rotation shaft 14 in the direction of the lines of centrifugal force. The second inlet 47 and the second outlet 52 are also arranged in regions opposite each other across the axis 14A of the rotation shaft 14 in the direction of the lines of centrifugal force. In other words, the first outlet 42 and the second outlet 52 are arranged in a region of the lubricant where a large amount of wear debris is mixed in, and the first inlet 35 and the second inlet 47 are arranged in a region of the lubricant where a small amount of wear debris is mixed in. With this arrangement, in a plan view, the direction in which the new lubricant pushes the old lubricant is generally from the first inlet 35 to the first outlet 42 and from the second inlet 47 to the second outlet 52, thereby reducing the amount of remaining old lubricant.

[0050] The first inlet 35 and the first outlet 42 are arranged at different positions in the axial direction of the rotation shaft 14, sandwiching the first bearing 21 therebetween. The second inlet 47 and the second outlet 52 are arranged at different positions in the axial direction of the rotation shaft 14, sandwiching the second bearing 22 therebetween. With this configuration, the new lubricant pushes the old lubricant in the overall direction from the first inlet 35 to the first outlet 42 and from the second inlet 47 to the second outlet 52, making it possible to reduce the amount of remaining old lubricant.

[0051] The sun shaft 12 and the rotation shaft 14 are arranged with their axes oriented vertically. The first inlet 35 is arranged above the first outlet 42, and the second inlet 47 is arranged above the second outlet 52. With this configuration, lubricant containing a large amount of wear powder can be efficiently discharged.

[0052] The sun shaft 12 and the rotation shaft 14 are arranged with their axes oriented vertically. Multiple bearings (two first bearings 21 and one second bearing 22) are arranged at intervals in the axial direction (up and down direction) of the rotation shaft 14. Two second oil seals 31 that seal between the rotation shaft 14 and the cylindrical support member 15 are arranged below the lowest second bearing 22. The second oil seals 31 prevent the lubricant filled inside the cylindrical support member 15 from leaking downward within the cylindrical support member 15 and also prevent foreign matter from entering the cylindrical support member 15 from below the gap between the outer circumferential surface of the rotation shaft 14 and the inner circumferential surface of the cylindrical support member 15. A metal closure plate 32 is arranged above the upper second oil seal 31 to liquid-tightly seal the gap between the second bearing 22 (the lowest bearing) and the second oil seal 31. The blocking plate 32 prevents the lubricant from leaking from the second bearing 22 to the second oil seal 31 when the pressure of the lubricant inside the cylindrical support member 15 increases when the lubricant is injected, or when centrifugal force acts on the lubricant during centrifugal barrel polishing operation.

[0053] The first bearing 21 and the second bearing 22 each have an outer ring 23, an inner ring 24, a plurality of rolling elements 25 arranged to be able to roll between the outer ring 23 and the inner ring 24, and a cage 26. The cage 26 holds the plurality of rolling elements 25 in a circumferentially positioned state. The outer ring 23, the inner ring 24, and the rolling elements 25 are made of metal, and the cage 26 is made of synthetic resin. This configuration makes it possible to suppress the generation of wear powder.

[0054] The sun axis 12 and the rotation axis 14 are oriented vertically, and the barrel tank 13 is disposed above the turret 11. The rotation axis 14 extends downward from the bottom surface of the barrel tank 13 and penetrates the turret 11. The cylindrical support member 15 protrudes below the turret 11, with the upper end of the cylindrical support member 15 fixed to the turret 11. The bearings supporting the rotation axis 14 include a first bearing 21 and a second bearing 22. A plurality of first bearings 21 (two in this Example 1) are arranged adjacent to each other in the vertical direction. At least a portion of the plurality of first bearings 21 in the vertical direction is disposed within the thickness range of the turret 11. The second bearing 22 is disposed below the first bearing 21 and the turret 11. The number of first bearings 21 is greater than the number of second bearings 22.

[0055] A large centrifugal force acts on the barrel tub 13 that rotates in a planetary motion with a mass (workpieces or grinding stones) placed inside, causing the rotation shaft 14 to tilt. At this time, the fulcrum of the rotation shaft 14 is the first bearing 21, so the load acting on the first bearing 21 is greater than that acting on the second bearing 22. To address this, the number of first bearings 21 is made greater than the number of second bearings 22. As a result, the pressing force from the rotation shaft 14 is distributed to multiple first bearings 21, reducing the frictional resistance in each first bearing 21 and suppressing the amount of wear powder generated in the first bearing 21.

[0056] Sun shaft 12 and rotation axis 14 are oriented vertically. Below first bearing 21, a leakage prevention member 30 is arranged to prevent the lubricant in first bearing 21 from leaking downward due to gravity. With this configuration, by preventing leakage of the lubricant, deterioration of the lubricating function of the lubricant is suppressed, and the proper bearing function of first bearing 21 is maintained.

[0057] <Other Examples> The present invention is not limited to the embodiments described above and illustrated in the drawings, and the following embodiments are also included within the technical scope of the present invention. In the first embodiment, rolling bearings with rolling elements were used as the first and second bearings, but the first and second bearings may also be plain bearings without rolling elements. In this case, the plain bearing is fixed to a cylindrical support member, and the rotation shaft is in sliding contact with the inner circumferential surface of the plain bearing. In the above Example 1, the first injection port and the second injection port are arranged in an area closer to the solar axis than the axis of the rotation axis, but the first injection port and the second injection port may also be arranged in an area farther from the solar axis than the axis of the rotation axis (an area closer to the outer edge of the turret). In the above-mentioned Example 1, the first inlet is placed at a higher position than the first outlet, but the first inlet may be placed at a lower position than the first outlet, or may be placed at the same height as the first outlet. In the above Example 1, the second inlet is positioned higher than the second outlet, but the second inlet may be positioned lower than the second outlet or at the same height as the second outlet. In the above Example 1, the first injection port was positioned higher than the first bearing, but the first injection port may be positioned at the same height as the first bearing or at a height corresponding to the upper end of the first bearing. In the above Example 1, the second injection port was positioned at a higher position than the second bearing, but the second injection port may be positioned at the same height as the second bearing or at a height corresponding to the upper end of the second bearing. In the above-mentioned Example 1, the first discharge port was positioned at a position lower than the first bearing, but the first discharge port may be positioned at the same height as the first bearing or at a height corresponding to the lower end of the first bearing. In the above Example 1, the second discharge port was positioned lower than the second bearing, but the second discharge port may be positioned at the same height as the second bearing or at a height corresponding to the lower end of the second bearing. In the first embodiment, the number of first bearings is greater than the number of second bearings, but the number of first bearings may be the same as or less than the number of second bearings. In the first embodiment, the first injection port is disposed on an imaginary line passing through the axis of the sun axis and the axis of the rotation axis, but the position of the first injection port may be disposed at a position deviated from the imaginary line. In the first embodiment, the first outlet is disposed on an imaginary line passing through the axis of the sun axis and the axis of the rotation axis, but the first outlet may be disposed at a position deviated from the imaginary line. In the above-described first embodiment, the second injection port is disposed on an imaginary line passing through the axis of the sun axis and the axis of the rotation axis, but the second injection port may be disposed at a position deviated from the imaginary line. In the first embodiment, the second outlet is disposed on an imaginary line passing through the axis of the sun axis and the axis of the rotation axis, but the second outlet may be disposed at a position deviated from the imaginary line. In the above-described first embodiment, the centrifugal barrel finishing machine is described in which the axes of the sun shaft and the rotation shaft are oriented vertically. However, the axes of the sun shaft and the rotation shaft may be oriented horizontally or obliquely relative to both the vertical and horizontal directions. In the first embodiment, the cages of the first and second bearings are made of synthetic resin, but the cages may also be made of metal. [Explanation of symbols]

[0058] 10...Centrifugal barrel polishing machine 11...Turret 11E...Outer edge of turret 12…Sun axis 13...Barrel tank 14...Rotation axis 14A...Axis of rotation axis 15...Cylindrical support member 21...First bearing 22...Second bearing 23...Outer ring 24...Inner circle 25...Rolling element 26...Cage 31...Second oil seal (oil seal) 32...occlusion plate 35...1st injection port (injection port) 42...1st discharge port (discharge port) 47…Second injection port (injection port) 52…Second discharge port (discharge port)

Claims

1. a turret that rotates around the sun axis; a barrel tank that is provided at an eccentric position of the turret so as to be rotatable relative to the turret and rotates in a planetary fashion; a cylindrical support member fixed to the turret and surrounding a rotation shaft that rotates integrally with the barrel tank; a bearing disposed inside the cylindrical support member and supporting the rotation shaft so that the rotation shaft can rotate relative to the cylindrical support member; an injection port disposed on an outer peripheral surface of the cylindrical support member for injecting a lubricant into the bearing; a discharge port disposed on the outer circumferential surface of the cylindrical support member for discharging the lubricant inside the cylindrical support member, The centrifugal barrel finishing machine, wherein the discharge port is disposed in a region closer to the outer periphery of the turret than to the axis of the rotation shaft.

2. 2. The centrifugal barrel finishing machine according to claim 1, wherein the injection port is disposed in a region closer to the sun axis than to the axis of the rotation shaft.

3. 3. The centrifugal barrel finishing machine according to claim 1, wherein the inlet and the outlet are disposed at different positions on either side of the bearing in the axial direction of the rotation shaft.

4. The sun axis and the rotation axis are arranged with their axes oriented vertically, 4. The centrifugal barrel finishing machine according to claim 3, wherein the inlet is disposed above the outlet.

5. The sun axis and the rotation axis are arranged with their axes oriented vertically, The plurality of bearings are arranged at intervals in the axial direction of the rotation shaft, an oil seal that seals between the rotation shaft and the cylindrical support member is disposed below the lowest bearing; 3. The centrifugal barrel finishing machine according to claim 1, further comprising a closing plate disposed above the oil seal for liquid-tightly closing the gap between the lowermost bearing and the oil seal.

6. The bearing is The outer ring and With inner circle, a plurality of rolling elements rollably disposed between the outer ring and the inner ring; a cage that holds the plurality of rolling elements in a circumferentially positioned state, the outer ring, the inner ring, and the rolling elements are made of metal, 3. The centrifugal barrel finishing machine according to claim 1, wherein the cage is made of synthetic resin.

Images