rotary table

Abstract

A rotary table has a base body, a movable wheel rotatably arranged on the base body, a fixed wheel arranged on an inner peripheral side of the movable wheel and fixed to the base body, and a plurality of rolling bodies. The rotary table includes a sensor fixed to the base body and a sensing fitting fixed to the movable wheel. The movable wheel has a scale extending along at least a portion of an outer peripheral side surface and a groove-shaped recess formed so as to be recessed inward from an outer periphery at a position corresponding to the scale in the outer periphery of the movable wheel. The sensing fitting has a foot portion fitted to the recess and a detected portion protruding outward from the foot portion and capable of being detected by the sensor. The foot portion is capable of being fixed to the movable wheel at any position of the recess.

Description

Technical Field

[0001] This invention relates to a rotary table. This application claims priority to Japanese Patent Application No. 2021-089430, filed on May 27, 2021, and invokes the entire contents of the aforementioned Japanese patent application. Background Technology

[0002] Regarding rotary tables, there are known techniques for controlling the rotation of a worktable by using sensing accessories fixed to the rotary table and sensors mounted on a base (for example, see Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 3-144151 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] Preferably, the rotation angle can be easily set and changed / adjusted within the rotary table. Therefore, one objective is to provide a rotary table that allows for easy setting and adjustment of the rotation angle.

[0008] means for solving problems

[0009] The rotary table of the present invention comprises: a base body having a planar retaining surface; a movable wheel rotatably disposed on the base body about an axis; a fixed wheel disposed on the inner circumferential side of the movable wheel and fixed to the base body; and a plurality of rolling elements configured to roll on the inner circumferential surface of the movable wheel and the outer circumferential surface of the fixed wheel. The rotary table includes: a sensor fixed to the base body; and a sensing accessory fixed to the movable wheel. The movable wheel has: a scale extending along at least a portion of its outer circumferential side; and a groove-shaped recess formed at a position corresponding to the scale on the outer circumference of the movable wheel, recessed from the outer periphery inwards. The sensing accessory has: a foot engaging with the recess; and a detection portion protruding outwards from the foot, detectable by the sensor. The foot can be fixed relative to the movable wheel at any position within the recess.

[0010] The effects of the invention

[0011] Based on the aforementioned rotary table, the rotation angle can be easily set and changed or adjusted. Attached Figure Description

[0012] Figure 1 This is a perspective view showing the structure of the rotary table according to the first embodiment.

[0013] Figure 2 This is a top view showing the structure of the rotary table according to the first embodiment.

[0014] Figure 3 This is a top view showing the structure of the rotary table according to the first embodiment.

[0015] Figure 4 This is a top view showing the structure of the base.

[0016] Figure 5 This is a cross-sectional view showing the structure of the rotary table according to the first embodiment.

[0017] Figure 6 It is an enlarged representation Figure 5 A partial sectional view.

[0018] Figure 7 This is a cross-sectional view showing the structure of the rotary table according to the first embodiment.

[0019] Figure 8 This is a cross-sectional view showing the structure of the rotary table according to the first embodiment.

[0020] Figure 9 This is a three-dimensional cross-sectional view showing the structure of the rotary table according to the first embodiment.

[0021] Figure 10 This is a top view showing the structure of the rotary table of the first embodiment after removing a portion of it.

[0022] Figure 11 This is a side view showing the structure of the worm gear unit.

[0023] Figure 12 This is a schematic three-dimensional diagram showing the structure of the worm gear housing.

[0024] Figure 13 This is a cross-sectional view showing the structure of the rotary table according to the first embodiment.

[0025] Figure 14 It is an exploded perspective view showing the worktable and sensing components of the rotary table.

[0026] Figure 15 This is a perspective cross-sectional view showing an enlarged portion of the structure of the rotary table according to the first embodiment.

[0027] Figure 16 This is an enlarged cross-sectional view showing a portion of the structure of the rotary table according to the first embodiment. Detailed Implementation

[0028] [Summary of Implementation Methods]

[0029] First, embodiments of the present invention will be listed and described. The rotary table of the present invention includes: a base body having a planar retaining surface; a movable wheel rotatably disposed on the base body about an axis; a fixed wheel disposed on the inner circumferential side of the movable wheel and fixed to the base body; and a plurality of rolling elements configured to roll on the inner circumferential surface of the movable wheel and the outer circumferential surface of the fixed wheel. The rotary table includes: a sensor fixed to the base body; and a sensing accessory fixed to the movable wheel. The movable wheel has: a scale extending along at least a portion of its outer circumferential side; and a groove-shaped recess formed at a position corresponding to the scale on the outer circumference of the movable wheel, recessed from the outer periphery inwards. The sensing accessory has: a foot engaging with the recess; and a detection portion protruding outwards from the foot, detectable by the sensor. The foot can be fixed relative to the movable wheel at any position within the recess.

[0030] A preferred rotary table is one that allows for easy setting, changing, and adjustment of the rotation angle. As is well known, conventional rotary tables control the rotation by using sensing components fixed to the rotary table and sensors fixed to a base. Changing the rotation angle requires altering the position of the sensor or the sensing component. However, sensors used in rotary tables are often supplied with dedicated brackets. Therefore, the installation position and orientation of the sensors are limited. Furthermore, space for the mounting bracket is often difficult to secure. In view of this, a sensor mounting structure is desired that can be used in small rotary tables, and one that allows for easy and reliable repositioning of the sensing component.

[0031] The inventors of this invention conducted repeated research on this problem and discovered that the rotary table of this invention can solve it. Specifically, the rotary table of this invention has graduations on the outer circumferential side of the movable wheel, and a recess is provided at a position corresponding to the graduations on the outer circumferential side of the movable wheel, where the sensing component is movably fixed. This structure makes it easy to confirm the installation position of the sensing component. Therefore, even when the user adjusts the rotation angle, the graduations can be observed and the rotation angle adjustment can be easily performed.

[0032] In the rotary table, the recess of the movable wheel is formed along the entire circumference of the outer peripheral side, and the foot of the sensing accessory can be a flat annular shape. According to this structure, the shape of the movable wheel is uniform throughout its circumference. Therefore, the stability of the rotary table's control and its durability for long-term use are further improved. Additionally, the sensing accessory can be secured more reliably.

[0033] In the rotary table, the movable wheel can be configured to include an outer wheel and a worktable, with the recess formed by combining the outer wheel and the worktable. The outer wheel includes the track surface of the rolling element, and the worktable is fixed to the upper surface of the outer wheel. According to this structure, existing rotary table outer wheel designs can be utilized to construct a movable wheel with graduations and a recess on its outer peripheral side. Thus, a rotary table with stable quality can be achieved at a reasonable cost.

[0034] In the rotary table, the sensing element can be configured to be a plurality of sensing elements, each of which can be independently fixed at any position relative to the movable wheel. According to this structure, the range of rotation angle settings becomes flexible, and furthermore, by combining it with an origin sensor, a rotary table applicable to a wide range of uses can be obtained.

[0035] In the rotary table, the outer wheel can be a worm gear with a first gear formed on its outer circumference. Additionally, the rotary table includes a worm unit fixed to the retaining surface. The worm unit may include: a worm, rotatable about an axis and having a second gear meshing with the first gear; and a worm housing surrounding and holding the worm, fixed in contact with the retaining surface on a planar contact surface. According to this structure, a rotary table driven by a so-called worm gear mechanism can be obtained, which can stably control rotation even under heavy loads and is particularly suitable for applications requiring small rotation angles.

[0036] In the rotary table, a scale can be formed on the upper surface of the worm housing, following the shape of the outer circumference of the movable wheel. According to this structure, the scale serving as a reference is easier to visually identify when adjusting the sensing accessory, and the sensing accessory is also easier to adjust.

[0037] In the rotary table, a cylindrical pin protruding from one of the holding surface and the contact surface is disposed therein, and a first recess is formed on the other of the holding surface and the contact surface. The first recess accommodates the pin and has a width corresponding to the pin, and the first recess extends radially along the worm gear. According to this structure, the tooth backlash of the worm gear device can be easily adjusted. By combining it with the above structure, a rotary table that is easier to use and has excellent operational stability can be obtained.

[0038] In the rotary table, the sensor can be configured such that it is held and fixed by a retaining member comprising a first plate member and a second plate member. The first plate member is fixed to the base body and is composed of a bent metal plate, while the second plate member is fixed to the first plate member and is also composed of a bent metal plate. According to this structure, even in situations where the sensor mounting space is limited, a simple structural member can be used to hold the sensor. By providing a sensor mounting member made of a metal plate, the range of sensor mounting positions and orientations is expanded, allowing the sensor to be mounted in the desired position and orientation.

[0039] [Specific examples of implementation methods]

[0040] Next, an example of a specific embodiment of the rotary table of the present invention will be described with reference to the accompanying drawings. In the following drawings, the same or corresponding parts are given the same reference numerals and will not be described again.

[0041] (First Implementation)

[0042] Figure 1 This is a perspective view showing the structure of the rotary table according to the first embodiment. Figure 1 In this context, the Z-axis direction is the direction (axial) extending along the rotation axis R of the worm gear. Figure 2 This is a top view showing the structure of the rotary table. Figure 3 From and Figure 2 A top view of the rotating platform viewed from the opposite perspective. Figure 4 Extract and represent the base that constitutes the rotary table. Figure 5 It means to Figure 2 A cross-sectional view of the state after the rotary table has been cut open by AA. Figure 6 It is an enlarged representation Figure 5 A cross-sectional view of the middle region α. Figure 7 It means to Figure 2 A cross-sectional view of the state after the rotary table is cut open in BB. Figure 8 It means to Figure 2 A cross-sectional view of the state after the rotary table is cut open by CC.

[0043] refer to Figures 1-3 The rotary table 1 of the first embodiment includes a base body 10, a rolling bearing unit 20, and a worm gear unit 30.

[0044] The base body 10 will now be described.

[0045] refer to Figure 1 The base body 10 is plate-shaped. (Reference) Figure 1 and Figure 4 The base body 10 has a first surface 101, a second surface 102 serving as a holding surface for the worm gear unit 30, and a third surface 103. (See reference) Figure 1 The thickness of the region corresponding to the first surface 101 is greater than the thickness of the region corresponding to the second surface 102. That is, in the Z-axis direction, the height of the second surface 102 is lower than the height of the first surface 101. The first surface 101 and the second surface 102 are connected by a third surface 103. (Reference) Figure 4 The first surface 101 is planar. Four through holes 105 extending along the thickness direction are formed at the corners of the first surface 101. An annular recess 101B is formed on the first surface 101, surrounding the through holes 107. A through hole 107 extending along the thickness direction is formed at the center of the recess 101B. Viewed from above along the Z-axis, the through hole 107 is circular in shape centered on the rotation axis R. An annular recess 101A is formed surrounding the recess 101B. (Reference) Figure 7 The thickness of the region of the first surface 101 corresponding to the recess 101A is greater than the thickness of the region of the first surface 101 corresponding to the recess 101B. (Reference) Figure 4 The shapes of the recesses 101A and 101B correspond to the worm gear 21 and inner gear 22 described later, respectively. Figure 5 On the recess 101B, a plurality of threaded holes 106 are formed at equal intervals along the circumference (eight in this embodiment). On the first surface 101, a plurality of threaded holes 104 are formed on the outer peripheral side of the recess 101A (four in this embodiment).

[0046] refer to Figure 4 In the Y-axis direction, the length L3 of the second surface 102 is shorter than the length L4 of the first surface 101. The second surface 102 is planar. Four through holes 108A, 108B, 108C, and 108D are formed on the second surface 102, extending along the thickness direction. The inner diameter of the through holes 108A, 108B, 108C, and 108D is larger than that of the screw 53 described later. Figure 3 The outer diameter of the threaded portion. On the second surface 102, a first recess 11 is formed between the through hole 108B and the through hole 108D. Viewed from above in the Z-axis direction, the first recess 11 is formed in the X-axis direction in a region closer to the long side opposite to the first surface 101 than the center of the second surface 102. (Reference) Figure 4 and Figure 6 A first threaded hole 12 communicating with the first recess 11 is formed on the base body 10. The first threaded hole 12 extends along the X-axis direction.

[0047] The rolling bearing unit 20 will now be described.

[0048] refer to Figure 7 and Figure 8The rolling bearing unit 20 includes: a worm gear 21 as an outer wheel; a worktable 61; an inner wheel 22 as a fixed wheel; and a plurality of first rollers 23 and a plurality of second rollers 24 as multiple rolling elements. The worm gear 21 is fixed to the worktable 61 to form a movable wheel 26. The worm gear 21 is disposed on the first surface 101 of the base body 10. The worm gear 21 is configured to correspond to the position of the recess 101A formed on the first surface 101. The worm gear 21 is disposed in a manner that aligns with the direction of the rotation axis R of the worm gear 21 and the direction perpendicular to the first surface 101 (Z-axis direction). The worm gear 21 is annular in shape.

[0049] The worm gear 21 includes: an inner circumferential surface 21A; an outer circumferential surface 21B; an axial end face 21D; and an axial end face 21E opposite to the end face 21D. A first gear 215 is formed along the entire circumferential direction of the outer circumferential surface 21B. The inner circumferential surface 21A includes a first region 211 and a second region 212. The first region 211 is located axially closer to the end face 21D than the center of the inner circumferential surface 21A. The second region 212 is located axially closer to the end face 21E than the center of the inner circumferential surface 21A. In the Z-axis direction, an annular recessed space 21C is formed between the first region 211 and the second region 212. The space 21C is surrounded by an annular first rolling surface 213 and an annular second rolling surface 214. The first rolling surface 213 and the second rolling surface 214 intersect (orthogonalize) each other. The space 21C is formed along the rolling path of a plurality of first rollers 23 and a plurality of second rollers 24.

[0050] The worktable 61 is fixed to the worm gear 21. The worktable 61 and the worm gear 21 constitute a movable wheel 26. The worktable 61 is annular. The worktable 61 includes: an outer peripheral surface 61A; an inner peripheral surface 61B; an axial end face 61D; and an axial end face 61E opposite to the end face 61D. The upper surface of the rotary table 1, i.e., the end face 61D of the worktable 61, is planar. The outer peripheral surface 61A includes a first part 611 and a second part 612. The diameter of the second part 612 is smaller than the diameter of the first part 611. Scales are provided on the entire circumference of the first part 611. Figure 1The first part 611 and the second part 612 are connected by an end face 613. The end face 613 is a surface parallel to the end face 21D of the worm gear 21. The diameter of the second part 612 is smaller than the diameter of the outer peripheral surface 21B of the outer wheel. By combining the worm gear 21 and the worktable 61, a recess 650 is formed, surrounded by the end face 613, the second part 612 of the outer peripheral surface, and the end face 21D of the worm gear 21. The recess 650 is a groove-shaped recess formed in a way that recesses inward from the outer periphery of the movable wheel 26. The recess 650 is formed on the entire circumference of the movable wheel 26. The diameter of the inner peripheral surface 61B of the worktable 61 is approximately equal to the diameter of the inner peripheral surface 22B of the inner wheel 22. On the worktable 61, a plurality of threaded holes 216 (eight in this embodiment) are formed at equal intervals along the circumference. Figure 1 The location where the threaded hole 216 is formed is the same as the location where eight threaded holes 226 are formed in the worm gear 21. Figure 10 The positions are matched. Four of the eight threaded holes 216 and 226 are used to secure the worktable 61 and the worm gear 21. Screw 256 ( Figure 15 Screw it into the threaded hole 216 of the worktable 61 and the threaded hole 226 of the worm gear 21. In this way, the worktable 61 is fixed on the worm gear 21.

[0051] The inner wheel 22 is annular. The inner wheel 22 is disposed on the inner circumferential side of the worm gear 21. The inner wheel 22 is configured to form a recess 101B in the first surface 101 of the base body 10. Figure 4 The inner wheel 22 corresponds to the positions of the first rollers 22A and the second rollers 22B. The inner roller 22 includes an outer peripheral surface 22A, an inner peripheral surface 22B, an axial end face 22D, and an axial end face 22E opposite to the end face 22D. The outer peripheral surface 22A includes a third region 221 and a fourth region 222. The third region 221 is positioned axially closer to the end face 22D than the center of the outer peripheral surface 22A. The fourth region 222 is positioned axially closer to the end face 22E than the center of the outer peripheral surface 22A. In the Z-axis direction, a circularly recessed space 22C is formed between the third region 221 and the fourth region 222. The space 22C is surrounded by a circularly shaped third rolling surface 223 and a circularly shaped fourth rolling surface 224. The third rolling surface 223 and the fourth rolling surface 224 intersect (orthogonalize) each other. The space 22C is formed along the rolling paths of the plurality of first rollers 23 and the plurality of second rollers 24. The first rolling surface 213 and the fourth rolling surface 224 face each other. In this embodiment, in a cross-section including the rotation axis R, the first rolling surface 213 and the fourth rolling surface 224 are arranged parallel to each other. The second rolling surface 214 and the third rolling surface 223 face each other. In this embodiment, in a cross-section including the rotation axis R, the second rolling surface 214 and the third rolling surface 223 are arranged parallel to each other.

[0052] On the inner wheel 22, a plurality of threaded holes 236 are formed at equal intervals along the circumference. Figure 16The location of the threaded hole 236 is the same as the location of the threaded hole 106 on the base body 10. Figure 3 The position matches, thread 52 ( Figure 3 Screw it into the threaded hole 106 of the base body 10 and the threaded hole 236 of the inner wheel 22. In this way, the inner wheel 22 is fixed on the base body 10.

[0053] refer to Figure 7 and Figure 8 The first roller 23 and the second roller 24 are cylindrical. The first roller 23 and the second roller 24 are alternately arranged circumferentially. The first roller 23 is configured to contact and roll on its outer peripheral surface 23A with the second rolling surface 214 and the third rolling surface 223. The second roller 24 is configured to contact and roll on its outer peripheral surface 24A with the first rolling surface 213 and the fourth rolling surface 224. The central axis of the first roller 23 intersects (or is orthogonal to) the central axis of the second roller 24. Here, the state in which the central axis of the first roller 23 intersects the central axis of the second roller 24 means that when the worm gear 21 rotates, if the centers of gravity of the first roller 23 and the second roller 24 pass through a predetermined point, then the central axis of the first roller 23 intersects (or is orthogonal to) the central axis of the second roller 24. Thus, the worm gear 21 can rotate relative to the base body 10 about the rotation axis R.

[0054] The worm gear unit 30 will now be described.

[0055] Figure 10 This is a top view showing the rotary table 1 after removing several structures including the worktable 61 and the worm housing 32. Figure 11 This is a side view of the extracted and represented worm gear unit 30. Figure 12 It is a three-dimensional view of the extracted worm housing 32. Figure 13 It is an enlarged cross-sectional view showing the area around the contact between the first gear 215 and the second gear 31A.

[0056] refer to Figure 1 The worm gear unit 30 is disposed on the second surface 102 of the base body 10. (Reference) Figure 10 and Figure 11The worm gear unit 30 includes: a worm 31; a worm housing 32; a pin 33; a motor 34; a coupling 35; a first support bearing 37; and a second support bearing 38. The worm 31 is cylindrical. A second gear 31A is formed on the outer circumferential surface of the worm 31. The second gear 31A meshes with a first gear 215. One end of the worm 31 is fixed to the inner wheel of the first support bearing 37. The outer wheel of the first support bearing 37 is fixed to the worm housing 32. The worm 31 is supported by the first support bearing 37 and is rotatable relative to the worm housing 32. A coupling 35 is disposed at the other end of the worm 31. The motor 34 is fixed by a motor accessory 34A and mounted on a motor bracket 35A. For example, a stepper motor or an AC (alternating current) servo motor can be used as the motor 34 in this embodiment. The worm 31 is supported by the second support bearing 38 and is rotatable relative to the coupling 35. The worm 31 is connected to the motor 34 via the coupling 35. Motor 34 is electrically connected to an external power source (not shown).

[0057] refer to Figure 12 The worm housing 32 is a cuboid with an internal space S. The worm housing 32 includes a first outer wall surface 32A, a second outer wall surface 32B (serving as a contact surface, bottom surface), a third outer wall surface 32C, a fourth outer wall surface 32D, a fifth outer wall surface 32E, and a sixth outer wall surface 32F. The first outer wall surface 32A, second outer wall surface 32B, third outer wall surface 32C, fourth outer wall surface 32D, and sixth outer wall surface 32F are planar. The first outer wall surface 32A and second outer wall surface 32B are arranged side-by-side in the Z-axis direction. The first outer wall surface 32A and second outer wall surface 32B are arranged in parallel. The third outer wall surface 32C and fourth outer wall surface 32D are arranged side-by-side in the X-axis direction. The third outer wall surface 32C and fourth outer wall surface 32D are arranged in parallel. The fifth outer wall surface 32E and sixth outer wall surface 32F are arranged in the Y-axis direction. A scale 98 is provided on the upper surface of the first outer wall 32A along the outer periphery of the movable wheel 26.

[0058] refer to Figure 6 and Figure 12 A recess 321 is formed on the second outer wall surface 32B, which serves as the bottom surface of the worm housing 32. An opening 324A communicating with the internal space S is formed on the third outer wall surface 32C. Four threaded holes 327 are formed around the opening 324A. The fifth outer wall surface 32E has a curved (arc-shaped) facing surface 322 that is recessed in the X-axis direction. A first through hole 323 communicating with the internal space S is formed on the facing surface 322. The worm housing 32 includes a flange portion 325 that protrudes from the facing surface 322 in the X-axis direction. The protruding end portion 325A of the flange portion 325 is curved (arc-shaped). The end portion 325A forms part of the fifth outer wall surface 32E.

[0059] refer to Figure 11 , Figure 12 A grease supply hole 326 is formed on the worm housing 32, extending from the fourth outer wall surface 32D to the opposing surface 322. The grease supply hole 326 has a first opening 326A on the opposing surface 322 and a second opening on the fourth outer wall surface 32D. The first opening 326A is formed at a distance from the first through hole 323 in the Y-axis direction. A grease nipple 328 is installed to close the second opening. By installing the grease nipple 328, the adjustment of the grease supply becomes easy.

[0060] refer to Figure 6 A cylindrical pin 33 is arranged to protrude from the second outer wall surface 32B. The pin 33 is embedded in the recess 321 of the second outer wall surface 32B. In this embodiment, the outer diameter of the pin 33 is slightly smaller than the width L5 of the first recess 11 of the base body 10 in the X-axis direction. Figure 4 ).

[0061] refer to Figure 11 and Figure 13 The worm housing 32 surrounds the worm 31. The worm 31 is housed within the internal space S formed by the worm housing 32. The second gear 31A of the worm 31 protrudes from the first through hole 323 of the worm housing. (Reference) Figure 6 The second outer wall surface 32B of the worm housing 32, which serves as the bottom surface, contacts the second surface 102 of the base body 10. The opposing surface 322 of the worm housing 32 faces the outer peripheral surface 21B of the worm wheel 21. (Reference) Figure 13 The second gear 31A exposed from the first through hole 323 of the facing surface 322 meshes with the first gear 215 of the worm gear 21.

[0062] refer to Figure 6 The pin 33 is inserted into the elongated first recess 11 of the base body 10. The rotary table 1 also has an internal hexagonal headstock retainer screw 40, which serves as a first screw screwed into the first threaded hole 12 of the base body 10. The end portion 40A of the internal hexagonal headstock retainer screw 40 contacts the outer peripheral surface 33A of the pin 33. (See reference) Figure 3 and Figure 4 The base body 10 is configured such that the positions of the through holes 108A, 108B, 108C, and 108D are matched with the positions of the threaded holes formed on the second outer wall surface 32B, which serves as the bottom surface of the worm housing 32, and screws 53 are screwed in. In this way, the worm housing 32 is fixed to the base body 10.

[0063] The method for fixing the worm gear unit 30 on the base body 10 will be described below.

[0064] First, prepare a structure on which the rolling bearing unit 20 is mounted on the base body 10. Then, as follows... Figure 2 As shown, a worm gear unit 30 is mounted on the base body 10. At this time, refer to... Figure 6The pin 33, which is pressed into the recess 321 of the worm housing 32, is inserted into the first recess 11 of the base body 10. Then, refer to Figure 2 , Figure 3 , Figure 4 By inserting screws 53 into the through holes 108A, 108B, 108C, and 108D, the worm housing 32 can be temporarily fixed to the base body 10. Next, refer to... Figure 2 This involves bringing the worm gear unit radially close to the first gear 215, applying appropriate force to bring the first gear 215 into contact with the second gear 31A. Next, refer to... Figure 6 The 40mm hex socket head cap screw is screwed into the first threaded hole 12. Then, refer to... Figure 2 , Figure 3 By tightening screw 53, the worm housing 32 can be fixed to the base body 10.

[0065] In this embodiment, the rotary table 1 has a width corresponding to the pin 33 (slightly larger than the outer diameter of the pin 33) and is shaped to extend radially along the worm gear 21. By inserting the pin 33 into the first recess 11, the movement of the worm housing 32 in the tangential direction of the worm gear 21 can be restricted, and the worm housing 32 can be moved radially. Furthermore, the worm housing 32 can be rotated relative to the base body 10 with the pin 33 as a fulcrum. By bringing the worm unit 30 closer to the first gear 215 along the radial direction of the worm gear, and applying appropriate force to bring the first gear 215 into contact with the second gear 31A, the tooth backlash between the first gear 215 and the second gear 31A can be appropriately adjusted by utilizing the radial movement of the worm housing 32 and the rotation with the pin 33 as a fulcrum. Therefore, adjusting the tooth backlash between the first gear 215 and the second gear 31A becomes easy. Thus, according to the rotary table 1 of this embodiment, the tooth backlash between the first gear 215 and the second gear 31A can be easily adjusted.

[0066] In the above embodiment, a first threaded hole 12 is formed, which communicates with the first recess 11 and has an opening facing the outer peripheral surface of the pin 33. The rotary table 1 is equipped with an internal hexagonal retaining screw 40, which is screwed into the first threaded hole 12 and has an end portion 40A that contacts the outer peripheral surface 33A of the pin 33. After adjusting the facing position of the worm housing 32 relative to the base body 10, the internal hexagonal retaining screw 40 is screwed into the first threaded hole 12. In this way, the relative movement of the worm housing 32 relative to the base body 10 can be restricted. Therefore, the change in tooth backlash between the first gear 215 and the second gear 31A over time can be suppressed.

[0067] In the above embodiment, the worm housing 32 has a facing surface 322 that faces the outer peripheral surface 21B of the worm wheel 21. The worm housing 32 includes a flange 325 that protrudes from the facing surface 322 and covers the side surface 215A of the first gear 215 facing the facing surface 322. By adopting such a structure, it is possible to reduce the entry of foreign objects into the area where the first gear 215 contacts the second gear 31A, and to reduce the scattering of grease to the outside of the rotary table 1.

[0068] In the above embodiments, reference Figure 5 , Figure 7 , Figure 8 The imaginary plane U includes the trajectory of the midpoint of the central axis of the first roller 23 and the trajectory of the midpoint of the central axis of the second roller 24. In this embodiment, the imaginary plane U includes the area where the first gear 215 contacts the second gear 31A. In the Z-axis direction, the height of the track center of the rolling bearing unit 20 is consistent with the tooth contact height between the first gear 215 and the second gear 31A in the worm unit 30. Because the rolling bearing unit 20 and the worm unit 30 are configured in this way, force is efficiently transmitted from the second gear 31A to the first gear 215, making it easy to optimize the tooth contact between the first gear 215 and the second gear 31A.

[0069] The following section describes the sensors and sensing components of the rotary table.

[0070] refer to Figure 1 The rotary table 1 has sensors 71, 72, and 73, which are fixed to the base body 10. Sensors 71, 72, and 73 are, for example, proximity sensors. Sensors 71 and 72 function as limit sensors. Sensor 73 functions as an origin sensor. Sensors 71 and 72 are mounted on the base body 10 via a retaining member, i.e., a retainer 91. Sensor 73 is mounted on the base body 10 via the retainer 93.

[0071] The rotary table 1 has sensing accessories 81, 82, and 83 fixed on movable wheels 26. Sensing accessories 81 and 82 are installed in the Z-axis direction at positions corresponding to sensors 71 and 72. Sensing accessory 83 is installed in the Z-axis direction at a position corresponding to sensor 73.

[0072] The installation structure of sensing components 81, 82, and 83 is described below. (Reference) Figure 1 , Figure 10 The sensing element 83, serving as the origin sensing element, is mounted on the outer peripheral side of the worm gear 21. The sensing element 83 is a component that protrudes outward from the outer peripheral side of the worm gear 21. The sensing element 83 is threadedly fixed in a threaded hole provided on the outer peripheral side of the worm gear 21.

[0073] refer to Figure 9 , Figure 14 , Figure 16 The sensing components 81 and 82 are composed of identical components. Each of the sensing components 81 and 82 has a flat, annular foot 811 or 821 and a detection portion 812 or 822 protruding outward from the foot. The detection portions 812 and 822 have a portion extending along the Z-axis direction. This shape facilitates detection by the sensors 71 and 72. The sensing components 81 and 82 are clamped in a recess 650 formed by the worktable 61 and the worm gear 21. A threaded hole 631 is formed on the worktable 61. The threaded hole 631 extends from the upper surface of the worktable 61, i.e., end face 61D, towards end face 613. Figure 7 A through hole is provided. By inserting and tightening the screw into the threaded hole 631, the sensing accessories 81 and 82 can be pressed and fixed. Furthermore, if the screw is loosened, the sensing accessories 81 and 82 can rotate circumferentially along the movable wheel 26 while held in the recess 650. That is, by loosening the screw, rotating the sensing accessories 81 and 82 to the desired position, and then tightening the screw again, the sensing accessories 81 and 82 can be fixed in any desired position. The sensing accessories 81 and 82 can move independently.

[0074] refer to Figure 15 , Figure 16 The worktable 61 and the worm gear 21 are fixed to each other by screws 256 inserted into threaded holes 216 and 226. On the other hand, the sensing components 81 and 82 can be fixed to the movable wheel 26 by screws inserted into threaded holes 631. With this structure, the positions of the sensing components 81 and 82 can be changed without removing the fixing between the worktable 61 and the worm gear 21. Furthermore, to determine the position of the sensing components, the scale formed on the outer peripheral surface 61A of the worktable 61 can be referenced. Therefore, positioning is easy. And, by utilizing the scale 98 (… Figure 12 It can be used for positioning, and the position of the sensing accessory can be easily set and changed on the user side.

[0075] refer to Figure 9 , Figure 10 The holding member, i.e., the holding body 91, for sensors 71 and 72 includes: a base portion 911 serving as a first plate member; and holding portions 912A and 912B serving as a second plate member. Figure 9For ease of understanding, sensors 71 and 72 are omitted. The base 911 is constructed from a bent metal plate. The base 911 is fixed to the base body 10 using screws 941 and 942. The base 911 contacts the upper surface 101 of the base body 10 and has: a first portion extending circumferentially corresponding to the outer periphery of the worm gear 21; and a second portion rising from the first portion along the Z-axis. Retaining portions 912A and 912B are fixed to the second portion of the base 911. Retaining portions 912A and 912B are constructed from a bent metal plate. Sensor 71 is clamped between the base 911 and the retaining portion 912A. Sensor 72 is clamped between the base 911 and the retaining portion 912B. By configuring the sensor retaining member with this structure, the sensor can be held using a retaining member formed from simple components. With such a retaining member, multiple sensors can be easily installed even in a small rotary table where the space for sensor installation is limited.

[0076] The retaining member, or retaining body 93, of sensor 73 includes: a base portion 931 serving as a first plate member; and a retaining portion 932 serving as a second plate member. Both the base portion 931 and the retaining portion 932 are constructed from a single bent metal plate. The base portion 931 is fixed to the upper surface, or first surface 101, of the base body 10 by screws. The retaining portion 932 is fixed relative to the base portion 931 by screws. Sensor 73 is held between the base portion 931 and the retaining portion 932. Although the orientations of sensors 71, 72, and 73 are different, the retaining bodies 91 and 93, composed of two plate members, can hold the sensor in any orientation.

[0077] (Modified Example)

[0078] The structure of fixing the sensing element to the movable wheel is not limited to the embodiments described above. For example, the sensing element may be integrally formed with the worktable and rotate relative to the worm gear while being fixed at any position. Alternatively, the sensing element may be integrally formed with the worm gear and rotate relative to the worktable while being fixed at any position. Furthermore, the number of sensing elements can be changed according to the target rotational movement. Alternatively, two sensing elements fixed relative to the outer wheel may be provided, and one movable sensing element movably held relative to the outer wheel may be provided.

[0079] The graduations and recesses provided on the outer circumference of the movable wheel are not limited to being provided on the entire circumference of the movable wheel. Alternatively, the graduations and recesses may be formed only on a portion of the outer circumference of the movable wheel, allowing the sensing accessory to move within the range of the recesses extending circumferentially.

[0080] It should be understood that all embodiments disclosed herein are exemplary and not limited to any particular embodiment. The scope of the invention is not limited by the foregoing description but is defined by the claims, which are intended to include all modifications within the meaning and scope of the claims.

[0081] Explanation of reference numerals in the attached figures

[0082] 1 Rotary worktable

[0083] 10 base bodies

[0084] 11First recess

[0085] Side walls of 11A, 11B, 11C, and 11D

[0086] 11E bottom wall surface

[0087] 12 First threaded hole

[0088] 13 Second threaded hole

[0089] Unit 20

[0090] 21 worm gear

[0091] 21A, 22B Inner circumferential surfaces

[0092] 21B, 22A, 23A, 24A, 33A, 412 outer peripheral surfaces

[0093] 21C and 22C spaces

[0094] 21D, 21E, 22D, 22E end faces

[0095] 22 inner wheel

[0096] 23 First Roller

[0097] 24 Second Roller

[0098] 25 cover components

[0099] 26 movable wheels

[0100] 30 worm gear unit

[0101] 31 worm gear

[0102] 31A Second Gear

[0103] 32 worm gear housing

[0104] 32A First Outer Wall

[0105] 32B Second Outer Wall

[0106] 32C Third Outer Wall

[0107] 32D Fourth Outer Wall

[0108] 32E Fifth Outer Wall

[0109] 32F Sixth Outer Wall

[0110] 33 sales

[0111] 34 motors

[0112] 34A ring

[0113] 35 coupling

[0114] 35A motor bracket

[0115] 37 First Support Bearing

[0116] 38 Second Support Bearing

[0117] 40mm internal hex bolt

[0118] 40A, 325A end section

[0119] 52, 53, Screws

[0120] 101 First Page

[0121] 101A, 101B, 321 concave part

[0122] 102 Second page

[0123] Page 103, third page

[0124] 104, 106, 216, 226, 236, 251, 327 threaded holes

[0125] Through holes 105, 107, 108A, 108B, 108C, 108D, 109

[0126] 211 First District

[0127] 212 Second Area

[0128] 213 First Rolling Surface

[0129] 214 Second Rolling Surface

[0130] 215 First Gear

[0131] 215A and 325A side views

[0132] 221 Third District

[0133] 222 Fourth District

[0134] 223 Third Rolling Surface

[0135] 224 Fourth Rolling Surface

[0136] 322 facing plane

[0137] 323 First Through Hole

[0138] 324A, 324B openings

[0139] 325 flange portion

[0140] 325B wall

[0141] 326 grease supply port

[0142] 326A First Opening

[0143] 326B Second Opening

[0144] 328 grease nipple

[0145] 412A, 412B, 412C, 412D outer wall surfaces

[0146] 61 workbench

[0147] Parts 611 and 612

[0148] 613 end face

[0149] 61A outer periphery

[0150] 61B inner circumferential surface

[0151] 61D and 61E end faces

[0152] 631 threaded hole

[0153] 650 recess

[0154] Sensors 71, 72, and 73

[0155] 81, 82, 83 Sensor Accessories

[0156] 811 feet

[0157] 812 tested department

[0158] 91, 92 Maintain body

[0159] 911, 931 Basic Department

[0160] 912A, 912B, 932 retaining section

[0161] 98 scale

Claims

1. A rotary table, wherein, have: The base has a planar retaining surface; A movable wheel is rotatably mounted on the base body about an axis; A fixed wheel is disposed on the inner circumference of the movable wheel and fixed to the base body; as well as Multiple rolling elements are configured to roll on the inner circumferential surface of the movable wheel and the outer circumferential surface of the fixed wheel. The rotary table includes: The sensor is fixed to the base body; and The sensing component is fixed to the movable wheel. The movable wheel has: The scale extends along at least a portion of the outer peripheral side; and The groove-shaped recess is formed at a position on the outer periphery of the movable wheel corresponding to the scale, and is recessed from the outer periphery inward. The sensing accessory has: The foot, which fits into the recess; and The part to be detected protrudes outward from the foot and can be detected by the sensor. The foot can be fixed relative to the movable wheel at any position in the recess.

2. The rotary table according to claim 1, wherein, The recess is formed around the entire circumference of the outer peripheral side of the movable wheel. The foot of the sensing accessory is in the shape of a flat ring.

3. The rotary table according to claim 1 or 2, wherein, The movable wheel includes: The outer wheel includes the track surface of the rolling element; and The worktable is fixed to the upper surface of the outer wheel. The recess is formed by combining the outer wheel with the worktable.

4. The rotary table according to claim 1 or 2, wherein, The sensing accessory comprises multiple sensing accessories, each of which can be independently fixed at any position relative to the movable wheel.

5. The rotary table according to claim 3, wherein, The outer wheel is a worm gear having a first gear formed on its outer circumferential surface along its entire circumference. The rotary table also includes a worm gear unit fixed to the retaining surface. The worm gear unit includes: A worm gear, rotatable about an axis, and having a second gear meshing with the first gear; and A worm housing surrounds and holds the worm, and is fixed in such a way that it contacts the holding surface on a planar contact surface.

6. The rotary table according to claim 5, wherein, On the upper surface of the worm housing, a scale is formed in a shape that follows the circumference of the outer wheel.

7. The rotary table according to claim 5, wherein, A cylindrical pin protruding from one of the retaining surface and the contact surface is disposed thereon. A first recess for receiving the pin is formed on the other side of the retaining surface and the contact surface. The first recess has a width corresponding to the pin and extends radially along the worm gear.

8. The rotary table according to claim 1, wherein, The sensor is held and fixed by a retaining member. The retaining member includes: The first plate component, fixed to the base body, is composed of a bent metal plate; The second plate component, fixed to the first plate component, is composed of a bent metal plate.

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