Vertical articulated robot

Abstract

To provide a vertical articulated robot capable of improving operational performance. [Solution] The fifth arm 225 is positioned within the first opening 110 and includes a first bearing 350A having an outer ring 350A1 and an inner ring 350A2 that rotatably supports the first shaft portion 310, a holding portion 710 fixed to the first projection 620, and an elastic member 720 positioned between the holding portion 710 and the first bearing 350A, and a pressing portion 700 that presses the outer ring 350A1 from the outside along the pivot axis J5, and the operating portion 311 protrudes outward from the first projection 620 and the pressing portion 700.

Description

Technical Field

[0001] The present invention relates to a vertical articulated robot.

Background Art

[0002] Patent Document 1 discloses a configuration of a robot in which an input bevel gear is rotatably supported via a bearing, and the axial movement of the bearing is restricted by pressing the bearing with a bearing retainer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the configuration described in Patent Document 1, when the bearing retainer is deformed due to thermal expansion or the like, the bearing cannot be firmly fixed, or the bearing is excessively pressed, so that the backlash of the input bevel gear does not fall within the appropriate range and the tooth contact accuracy deteriorates.

Means for Solving the Problems

[0005] The vertical articulated robot comprises a root arm member having a motor, a first arm member provided on the root arm member and rotating around a first axis, and a second arm member provided on the first arm member and rotating around a second axis intersecting the first axis, wherein the first arm member has a housing having a first projection protruding along the first axis and an opening provided inside the first projection, a first axis portion extending along the first axis, and a step or The gear comprises an operating portion including a recess and a bevel gear having a bevel tooth portion provided at the other end of the first shaft portion, which is inserted into the opening; a first bearing disposed within the opening and having an outer ring and an inner ring that rotatably supports the first shaft portion; a holding portion fixed to the first protrusion; and an elastic member disposed between the holding portion and the first bearing, which presses the outer ring from the outside along the first shaft, wherein the operating portion protrudes outward from the first protrusion and the pressing portion. [Brief explanation of the drawing]

[0006] [Figure 1] A schematic diagram showing the configuration of a vertical articulated robot. [Figure 2] A cross-sectional view showing the configuration of the tip of a vertical articulated robot. [Figure 3] Figure 2 shows a magnified cross-sectional view of section A of the vertical articulated robot. [Figure 4] Figure 3 is a magnified perspective view showing part B of the vertical articulated robot. [Figure 5] Figure 3 is a magnified perspective view showing part B of the vertical articulated robot. [Figure 6] Figure 3 shows a magnified cross-sectional view of section B of the vertical articulated robot. [Figure 7A] A perspective view showing the configuration of the holding part that constitutes the pressing part. [Figure 7B] A perspective view showing the configuration of the elastic members that make up the pressing section. [Figure 7C] A perspective view showing the configuration of the spacers that make up the pressing section. [Figure 8] A plan view showing the configuration of the pressing section. [Figure 9] A cross-sectional diagram illustrating the method for adjusting backlash. [Figure 10A] A perspective view showing the configuration of the elastic member in a modified example. [Figure 10B] A perspective view showing the configuration of the elastic member in a modified example. [Figure 10C] A perspective view showing the configuration of the elastic member in a modified example. [Figure 11A] A perspective view showing the configuration of a modified spacer. [Figure 11B] A perspective view showing the configuration of a modified spacer. [Figure 12A] A plan view showing the configuration of the holding part in a modified example. [Figure 12B] A cross-sectional view of the retaining part along the CC line shown in Figure 12A. [Figure 13] A cross-sectional view showing the configuration of a modified vertical articulated robot. [Modes for carrying out the invention]

[0007] The configuration of the vertical articulated robot 1 will be explained below with reference to the drawings. In the following diagrams, the three mutually orthogonal axes will be referred to as the X-axis, Y-axis, and Z-axis. The direction along the X-axis will be called the "X direction," the direction along the Y-axis will be called the "Y direction," and the direction along the Z-axis will be called the "Z direction." The direction of the arrow is the + direction, and the direction opposite to the + direction is the - direction. Viewing from the +Z direction or -Z direction is also called a planar view or a planar perspective.

[0008] First, the configuration of the vertical articulated robot 1 will be explained with reference to Figure 1.

[0009] As shown in Figure 1, the vertical articulated robot 1 comprises a robot body 2 and a controller 10 that controls the driving of the robot body 2.

[0010] The vertical articulated robot 1 is, for example, a 6-axis robot having 6 drive axes. The vertical articulated robot 1 has a base 21 fixed to the floor and a robot arm 22 connected to the base 21.

[0011] The robot arm 22 has a first arm 221, a second arm 222, a third arm 223, a fourth arm 224 as a base arm member, a fifth arm 225 as a first arm member, and a sixth arm 226 as a second arm member.

[0012] The first arm 221 is connected to the base 21 and rotates around a rotation axis J1 with respect to the base 21. The second arm 222 is connected to the first arm 221 and rotates around a rotation axis J2 with respect to the first arm 221. The third arm 223 is connected to the second arm 222 and rotates around a rotation axis J3 with respect to the second arm 222. The fourth arm 224 is connected to the third arm 223 and rotates around a rotation axis J4 with respect to the third arm 223. The fifth arm 225 is connected to the fourth arm 224 and rotates around a rotation axis J5 as a first axis with respect to the fourth arm 224. The sixth arm 226 is connected to the fifth arm 225 and rotates around a rotation axis J6 as a second axis with respect to the fifth arm 225. An end effector 24 is connected to the tip of the sixth arm 226. Also, the base and the first arm 221, and between each arm are connected via joints. Each rotation axis is a virtual straight line.

[0013] The robot body 2 has a first drive mechanism 231, a second drive mechanism 232, a third drive mechanism 233, a fourth drive mechanism 234, a fifth drive mechanism 235, and a sixth drive mechanism 236.

[0014] The first drive mechanism 231 rotates the first arm 221 around the pivot axis J1 relative to the base 21. The second drive mechanism 232 rotates the second arm 222 around the pivot axis J2 relative to the first arm 221. The third drive mechanism 233 rotates the third arm 223 around the pivot axis J3 relative to the second arm 222. The fourth drive mechanism 234 rotates the fourth arm 224 around the pivot axis J4 relative to the third arm 223. The fifth drive mechanism 235 rotates the fifth arm 225 around the pivot axis J5 relative to the fourth arm 224. The sixth drive mechanism 236 rotates the sixth arm 226 around the pivot axis J6 relative to the fifth arm 225.

[0015] The controller 10 independently controls the drive mechanisms 231 to 236, causing the robot body 2 to perform predetermined tasks. The controller 10 is, for example, composed of a computer and includes a processor for processing information, a memory connected to the processor for communication, and an external interface. Various programs that can be executed by the processor are stored in the memory. The processor can read and execute various programs stored in the memory.

[0016] Next, with reference to Figures 2 and 3, the configuration of the tip arms, specifically the fourth arm 224 to the sixth arm 226, will be described.

[0017] As shown in Figures 2 and 3, the fourth arm 224 has a bifurcated tip, and the fifth arm 225 is supported from both sides of the pivot axis J5 between the two prongs. The sixth drive mechanism 236 is located at the upper tip 224a, and the fifth drive mechanism 235 is located at the lower tip 224b. By supporting the fifth arm 225 from both sides in this manner, the rotational accuracy of the fifth arm 225 is improved, and separate spaces can be secured for the fifth drive mechanism 235 and the sixth drive mechanism 236.

[0018] The fourth arm 224 includes a housing 31 and a cover 32 attached to the housing 31. The base end of the housing 31 is rotatably connected to the third arm 223. The tip end of the housing 31 is rotatably connected to the fifth arm 225.

[0019] The housing 31 is fixed to a motor 41 with a built-in encoder, a pulley 43 attached to the output shaft of the motor 41, and a power transmission belt 45 wrapped around the pulley. The housing 31 is also fixed to a motor 61 with a built-in encoder, a pulley 63 attached to the output shaft of the motor 61, and a power transmission belt 65 wrapped around the pulley 63.

[0020] As shown in Figure 3, the fifth arm 225 includes a housing 100, a first bevel gear 300 as a bevel gear, a first bearing 350, a second bearing 640, a second bevel gear 400, and a third bearing 450.

[0021] The housing 100 has a first opening 110 as an opening, and a second opening 120 located at a different position from the first opening 110. The first opening 110 and the second opening 120 are connected internally.

[0022] The first bevel gear 300 is inserted into the first opening 110. The first bevel gear 300 has a first shaft portion 310 extending along the pivot axis J5 which serves as the first shaft, an operating portion 311 including a step or recess provided at one end 310a of the first shaft portion 310, and a first bevel tooth portion 312 provided at the other end 310b of the first shaft portion 310.

[0023] The first shaft portion 310 has a stepped shape in which the diameter increases from the operating portion 311 toward the first bevel tooth portion 312. The first bearing 350 has a plurality of first bearings 350A, 350B arranged in accordance with the stepped shape.

[0024] The first bearing 350 rotatably supports the first shaft portion 310 with respect to the housing 100. The first bearing 350 includes a first bearing 350A located on one end 310a of the first shaft portion 310, and a first bearing 350B located on the other end 310b of the first shaft portion 310.

[0025] The second bevel gear 400 is inserted into the second opening 120. The second bevel gear 400 has a second shaft portion 410 extending along the pivot axis J6 which serves as the second shaft, a second bevel tooth portion 412 provided at one end 410a of the second shaft portion 410 which receives force by meshing with the first bevel tooth portion 312, and a connecting portion 411 provided at the other end 410b of the second shaft portion 410.

[0026] The second shaft portion 410 has a stepped shape in which the diameter increases from the connecting portion 411 toward the second bevel tooth portion 412. The third bearing 450 has a plurality of third bearings 450A, 450B arranged in accordance with the stepped shape.

[0027] The third bearing 450 rotatably supports the second shaft portion 410 with respect to the housing 100. The third bearing 450 includes a third bearing 450A positioned on one end 410a of the second shaft portion 410 and a third bearing 450B positioned on the other end 410b of the second shaft portion 410.

[0028] As described above, the first shaft portion 310 and the second shaft portion 410 have a stepped shape in which the diameter increases toward the center of the housing 100, making it possible to insert multiple bearings 350A, 350B, 450A, and 450B in sequence, thereby facilitating the assembly of the fifth arm 225.

[0029] The sixth arm 226 includes a flange 500, a reduction gear 510 connected to the flange 500 that amplifies the force received and drives the flange 500, and a fitting member 520 inserted into the reduction gear 510 and detachably fitted to the connection portion 411 of the second shaft portion 410.

[0030] A recess 520a is provided on a part of the fitting member 520, specifically on the side of the connecting portion 411 of the second bevel gear 400. A protrusion 411a is provided on a part of the connecting portion 411 of the second bevel gear 400. The second bevel gear 400 and the fitting member 520 are arranged with the recess 520a and the protrusion 411a fitted together.

[0031] In this way, the recess 520a and the protrusion 411a fit together, allowing the positions of the second bevel gear 400 and the fitting member 520, in other words, the fifth arm 225 and the reduction gear 510 to be determined. Specifically, since the second bevel gear 400 is supported by two third bearings 450A and 450B, even when the reduction gear 510 is attached to the second bevel gear 400, deflection of the second bevel gear 400 can be suppressed. In addition, since the length of the fitting member 520, which has a large outer diameter, can be shortened, material costs can be reduced.

[0032] The fitting member 520 is provided with a through hole 521. The end of the second bevel gear 400 on the connection portion 411 side is provided with a female thread portion 420. The fitting member 520 is supported by the interlocking of its recess 520a and protrusion 411a, and is fixed to the female thread portion 420 of the second bevel gear 400 by a fixing screw 530 that passes through the through hole 521.

[0033] In this way, the fitting member 520 and the second bevel gear 400 are fixed together, allowing the fifth arm 225 on which the second bevel gear 400 is positioned and the reduction gear 510 into which the fitting member 520 is inserted to be easily attached and detached.

[0034] The gear reducer 510 is, for example, a wave gear reducer having a wave generator. A fifth bearing 540 is positioned on the outer circumference of the fitting member 520 on the side of the sixth arm 226. In this way, the side of the gear reducer 510 to which the fitting member 520 is inserted, on the side of the fifth arm 225, is supported by the recess 520a of the fitting member 520 and the protrusion 411a of the second bevel gear 400 fitting together. On the other hand, the side of the gear reducer 510 to which the fitting member 520 is inserted, on the side of the sixth arm 226, is supported by the fifth bearing 540. In other words, the wave generator of the gear reducer 510 has a double-support structure, so that the gear reducer 510 does not become eccentric, and abnormal wear of the tooth surface due to eccentricity is suppressed.

[0035] Next, with reference to Figures 4 to 6, the configuration of the connection between the fourth arm 224 and the fifth arm 225 will be explained in detail.

[0036] As shown in Figure 4, the vertical articulated robot 1 has a fourth arm 224, a fifth arm 225, and a sixth arm 226.

[0037] As described above, the fourth arm 224 includes a motor 61 (see Figure 2), a pulley 63 (see Figure 2) attached to the output shaft of the motor 61, and a power transmission belt 65 wrapped around the pulley 63. As shown in Figure 5, the fourth arm 224 has a cylindrical second projection 610 that protrudes in the -Z direction along the pivot axis J5.

[0038] The fifth arm 225 has a substantially cylindrical first projection 620 that protrudes in the +Z direction along the pivot axis J5. The first projection 620 is part of the housing 100. Inside the first projection 620 is a first opening 110, which serves as an opening into which the first bevel gear 300, constituting the power transmission mechanism, is inserted. The second bearing 640 is supported on the outside of the first projection 620. The first bearing 350A is supported on the inside of the first projection 620.

[0039] A pressing portion 700 that supports the first bearing 350A is positioned at the tip of the first projection 620, that is, at the end on the +Z direction side. The first bearing 350A has an outer ring 350A1 and an inner ring 350A2. The pressing portion 700 is fixed to the first projection 620 by being pressed against the direction of the pivot axis J5, specifically in the -Z direction, by the holding portion 710.

[0040] The pressing portion 700 includes a retaining portion 710 fixed to the first protruding portion 620, a spacer 730 positioned on the first bearing 350A side, and an elastic member 720 positioned between the retaining portion 710 and the spacer 730. The pressing portion 700 presses the outer ring 350A1 of the first bearing 350A from the outside along the pivot axis J5.

[0041] As shown in Figure 6, the fourth arm 224 has a cylindrical second projection 610 that protrudes in the -Z direction along the pivot axis J5. The second projection 610 has a stepped portion 610a on its inner side. Specifically, the second projection 610 is provided such that its thickness increases as it extends in the +Z direction.

[0042] The second projection 610 has a shoulder portion 611 on a part of the stepped portion 610a. The shoulder portion 611 has a wall portion extending along a hypothetical straight line parallel to the pivot axis J5, and a bottom portion extending along a hypothetical first straight line intersecting, in particular perpendicular to, the pivot axis J5. Inside the shoulder portion 611 is a second bearing 640. The second bearing 640 is an annular member that rotatably supports the fifth arm 225 relative to the fourth arm 224, and has an inner ring 640A and an outer ring 640B positioned outside the inner ring 640A.

[0043] The second bearing 640 is fixed to the outer ring 640B by being sandwiched between the bottom of the shoulder portion 611 of the second projection 610 and the outer ring clamping portion 612. The outer ring clamping portion 612 extends along a hypothetical second straight line that intersects, and in particular orthogonal to, the pivot axis J5, and is fixed to the second projection 610 by being pressed against the direction of the pivot axis J5, specifically in the +Z direction, by fixing bolts 613. The first and second straight lines are parallel, that is, the bottom of the shoulder portion 611 and the outer ring clamping portion 612 are parallel, but the first and second straight lines do not have to be parallel.

[0044] The fifth arm 225 has a substantially cylindrical first projection 620 that protrudes in the +Z direction along the pivot axis J5. The first projection 620 is part of the housing 100 described above. The first projection 620 has stepped portions 620a on the inside and outside. Specifically, the first projection 620 is provided such that its thickness increases as it extends in the -Z direction.

[0045] Inside the first projection 620, as described above, there is a first opening 110 into which the first bevel gear 300, which constitutes the power transmission mechanism, is inserted. The inner ring 640A of the second bearing 640 is supported on the outside of the first projection 620. The outer ring 350A1 of the first bearing 350A is supported on the inside of the first projection 620.

[0046] In this way, the outer ring 640B of the second bearing 640 is fixed to the second projection 610 by the outer ring clamping portion 612, or in other words, the second bearing 640 is fixed to the fourth arm 224. Therefore, the fifth arm 225 can be made lighter compared to the case where the second projection 610 is located on the fifth arm 225. Thus, the operational performance of the fifth arm 225 can be improved.

[0047] As described above, the first bevel gear 300 is inserted into the first opening 110 of the first projection 620. The outer ring 350A1 of the first bearing 350A, which rotatably supports the first bevel gear 300, is positioned in a part 111 of the first opening 110.

[0048] A pressing portion 700 that supports the outer ring 350A1 of the first bearing 350A is positioned at the tip of the first projection 620, that is, at the end on the +Z direction side. As described above, the pressing portion 700 has a retaining portion 710 fixed to the first projection 620, a spacer 730 positioned on the first bearing 350A side, and an elastic member 720 positioned between the retaining portion 710 and the spacer 730. The retaining portion 710 is fixed to the first projection 620 by being pressed against the direction of the pivot axis J5, specifically in the -Z direction, by a fixing bolt 613.

[0049] In this way, since the first bearing 350A is fixed by the holding part 710, the elastic member 720, the spacer 730, that is, the pressing part 700 and the fixing bolt 613, it is possible to suppress fretting due to differences in thermal expansion, i.e., minute wear, and the generation of abnormal noise and vibration.

[0050] Furthermore, since the first bearing 350A is positioned in a part 111 of the first opening 110 of the first projection 620, and the second bearing 640 is positioned on the outside of the first projection 620, that is, the first projection 620 can support both bearings 350A and 640, the size of the first projection 620 can be made more compact, and the size of the fifth arm 225 can be reduced. Specifically, this can contribute to shortening the arm length of the fifth arm 225, reducing the inertia of the fifth arm 225, and improving the operating performance by reducing the moment of inertia.

[0051] Furthermore, the first projection 620 is shaped so that its thickness decreases towards the tip side, i.e., the side in the +Z direction. The second bearing 640 is positioned closer to the tip than the first bearing 350A. In this way, since the second bearing 640 is positioned on the tip side of the first projection 620 where the thickness decreases, it is possible to make the size of the first projection 620, including the second bearing 640, more compact, and thus the size of the fifth arm 225 can be reduced.

[0052] An operating portion 311, including a step or recess, is provided at one end 310a of the first shaft portion 310 of the first bevel gear 300. The presence of the step or recess allows the amount of play to be checked by rotating the operating portion 311 when adjusting the backlash between the first bevel gear 300 and the second bevel gear 400.

[0053] The operating part 311 is positioned to protrude outward from the first protrusion 620 and the pressing part 700, i.e., in the +Z direction (see Figure 9). In this way, since the operating part 311 protrudes outward from the surrounding first protrusion 620 and pressing part 700, there are no obstructing members, and tooth contact adjustment can be easily performed.

[0054] As described above, the pressing portion 700 for fixing the first bearing 350A has an elastic member 720, which makes it difficult for a gap to form between the pressing portion 700 and the first bearing 350A, and prevents excessive pressure from being applied to the first bearing 350A by compressing the elastic member 720, thereby maintaining the backlash between the first bevel gear 300 and the second bevel gear 400 within an appropriate range. Therefore, the tooth contact accuracy can be improved.

[0055] Furthermore, since the elastic member 720 is sandwiched between the holding part 710 and the spacer 730, if the elastic member is crushed, it is possible to prevent the elastic member from protruding in the direction of the first bearing. Therefore, it is possible to minimize the impact on the movement of the arm.

[0056] Furthermore, the outer ring clamping portion 612 fixes the outer ring 640B of the second bearing 640 to the second projection portion 610. In other words, the second bearing 640 and the outer ring clamping portion 612 can be fixed to the fifth arm 225. Therefore, compared to the case where the second bearing 640 and the outer ring clamping portion 612 are arranged on the sixth arm 226, for example, the fifth arm 225 can be made lighter. Thus, the operational performance of the fifth arm 225 can be improved.

[0057] Furthermore, since the second shaft portion 410 of the second bevel gear 400 is supported by the housing 100 via the third bearing 450, the second bevel gear 400 can be fixed to the housing 100 whether the reduction gear 510 is connected to the second bevel gear 400 or removed from the second bevel gear 400. Therefore, it becomes possible to adjust the backlash between the first bevel gear 300 and the second bevel gear 400, in other words, to adjust the tooth contact, thereby preventing the gap between the first bevel gear 300 and the second bevel gear 400 from becoming too large. This improves the operational performance of the fifth arm 225 and the sixth arm 226.

[0058] Next, the configuration of the pressing section 700 will be explained with reference to Figures 7A, 7B, 7C, and 8. Figure 8 is a plan view of the pressing section 700 as seen from the +Z direction, that is, a plan view showing the relative positions of the holding section 710, the elastic member 720, and the spacer 730 when they are stacked on top of each other.

[0059] As shown in Figures 7A to 8, the pressing portion 700 includes, as described above, a holding portion 710 fixed to the first protruding portion 620, a spacer 730 positioned on the first bearing 350A side, and an elastic member 720 positioned between the holding portion 710 and the spacer 730.

[0060] As shown in Figure 7A, the retaining portion 710 is configured in a circular shape having a through hole 711 as a first through hole. The first shaft portion 310 of the first bevel gear 300 is inserted into the through hole 711. Through holes 712 are provided around the through hole 711 into which fixing bolts 613 used for fixing to the first protrusion 620 are inserted. In this embodiment, for example, four through holes 712 are provided at equal intervals.

[0061] As shown in Figure 7B, the elastic member 720 is configured in a circular shape with a through hole 721 as the first through hole. The first shaft portion 310 of the first bevel gear 300 is inserted into the through hole 721.

[0062] As shown in Figure 7C, the spacer 730 is configured in a circular shape having a through hole 731 as a first through hole. The first shaft portion 310 of the first bevel gear 300 is inserted into the through hole 731. Around the through hole 731, there are through holes 732 as second through holes to absorb a portion of the elastic member 720 that moves when the elastic member 720 is crushed. In this embodiment, for example, four through holes 732 are provided at equal intervals. By providing the through holes 732, even if the elastic member 720 is crushed, it is possible to prevent a portion of the elastic member 720 from coming into contact with the first shaft portion 310 of the first bevel gear 300 which is located inside.

[0063] As shown in Figure 8, the pressing portion 700 includes a holding portion 710 positioned on the uppermost surface, an elastic member 720 positioned below the holding portion 710, and a spacer 730 positioned below the elastic member 720.

[0064] The inner diameter end 710a of the retaining portion 710 protrudes inward by a length L1, i.e., toward the first shaft portion 310, compared to the inner diameter end 720a of the elastic member 720. The inner diameter end 730a of the spacer 730 protrudes inward by a length L2, i.e., toward the first shaft portion 310, compared to the inner diameter end 720a of the elastic member 720. In other words, the inner diameter end 720a of the elastic member 720 is positioned further away from the first shaft portion 310 than the end 710a of the retaining portion 710 and the end 730a of the spacer 730.

[0065] In this way, the end 710a of the holding portion 710 protrudes inward more than the end 720a of the elastic member 720, and the end 730a of the spacer 730 protrudes inward more than the end 720a of the elastic member 720. Therefore, even if pressure is applied to the elastic member 720 when the pressing portion 700 is pressed and the elastic member 720 is crushed, it is possible to prevent contact with the first shaft portion 310 of the first bevel gear 300 which is positioned on the inside, thereby preventing it from affecting the operation of the fifth arm 225.

[0066] Furthermore, since the holding portion 710, i.e., the pressing portion 700, is fixed by a fixing bolt 613 as a fixing screw, it becomes possible to fix the first bearing 350A with a predetermined force, thereby suppressing looseness of the first bearing 350A. In Figure 8, the outer diameter of the holding portion 710 is shown as the end portion 710b, the outer diameter of the elastic member 720 is shown as the end portion 720b, and the outer diameter of the spacer 730 is shown as the end portion 730b.

[0067] As described above, the vertical articulated robot 1 comprises a fourth arm 224 having motors 41 and 61, a fifth arm 225 provided on the fourth arm 224 and rotating around a pivot axis J5, and a sixth arm 226 provided on the fifth arm 225 and rotating around a pivot axis J6 intersecting the pivot axis J5. The fifth arm 225 has a housing 100 having a first projection 620 protruding along the pivot axis J5 and a first opening 110 provided inside the first projection 620, a first shaft portion 310 extending along the pivot axis J5, and an operating portion 3 provided at one end 310a of the first shaft portion 310 and including a step or recess. The first bevel gear 300, which is inserted into the first opening 110, has a first bevel tooth portion 312 provided at the other end 310b of the first shaft portion 310, and a first bearing 350A, which is disposed inside the first opening 110 and has an outer ring 350A1 and an inner ring 350A2, and rotatably supports the first shaft portion 310, and a pressing portion 700, which has a holding portion 710 fixed to the first projection portion 620 and an elastic member 720 disposed between the holding portion 710 and the first bearing 350A, and presses the outer ring 350A1 from the outside along the pivot axis J5, and the operating portion 311 protrudes outward from the first projection portion 620 and the pressing portion 700.

[0068] With this configuration, the pressing portion 700 for fixing the first bearing 350A has an elastic member 720, which makes it difficult for a gap to form between the pressing portion 700 and the first bearing 350A, and prevents excessive pressure from being applied to the first bearing 350A by compressing the elastic member, thereby maintaining the backlash of the first bevel gear 300 within an appropriate range. Therefore, the tooth contact accuracy can be improved. In addition, since the operating portion 311 protrudes more than the surrounding first protrusion 620 and pressing portion 700, tooth contact adjustment can be easily performed.

[0069] Furthermore, by maintaining the backlash within an appropriate range, sliding irregularities of the first bearing 350A can be suppressed. This allows for stable torque during the drive of the first bevel gear 300.

[0070] Furthermore, in the vertical articulated robot 1 of this embodiment, it is preferable that the inner diameter end 710a of the holding portion 710 protrudes inward more than the inner diameter end 720a of the elastic member 720. With this configuration, since the end 710a of the holding portion 710 protrudes inward more than the end 720a of the elastic member 720, in other words, the end 720a of the elastic member 720 does not protrude inward, even if pressure is applied to the elastic member 720 when the pressing portion 700 is pressed and the elastic member 720 is crushed, it is possible to suppress contact with the first bevel gear 300 which is located on the inside, and thus suppress the effect on the operation of the fifth arm 225.

[0071] Furthermore, in the vertical articulated robot 1 of this embodiment, it is preferable that a spacer 730 is placed between the elastic member 720 and the first bearing 350A. With this configuration, the elastic member 720 is sandwiched between the holding part 710 and the spacer 730, so if the elastic member 720 is crushed, it is possible to prevent the elastic member 720 from protruding in the direction of the first bearing 350A. Therefore, it is possible to minimize the impact on the movement of the fifth arm 225.

[0072] Furthermore, in the vertical articulated robot 1 of this embodiment, it is preferable that the inner diameter end 730a of the spacer 730 protrudes further inward than the inner diameter end 720a of the elastic member 720. With this configuration, the end 730a of the spacer 730 protrudes further inward than the end 720a of the elastic member 720, in other words, the end 720a of the elastic member 720 does not protrude further inward. Therefore, even if pressure is applied to the elastic member 720 when the pressing part 700 is pressed and the elastic member 720 is crushed, it is possible to prevent contact with the first bevel gear 300 located on the inside, thereby preventing it from affecting the operation of the fifth arm 225.

[0073] Furthermore, in the vertical articulated robot 1 of this embodiment, it is preferable that the pressing portion 700 has a fixing bolt 613, and that a through hole 712 through which the fixing bolt 613 passes is provided on the outside of the holding portion 710. With this configuration, since the holding portion 710 is fixed by the fixing bolt 613, it becomes possible to fix the first bearing 350A with a predetermined force, and it is possible to suppress the first bearing 350A from wobbling in the axial direction of the pivot axis J5.

[0074] Furthermore, in the vertical articulated robot 1 of this embodiment, it is preferable that the fourth arm 224 has a cylindrical second projection 610 that protrudes along the rotation axis J5 and has a shoulder portion 611 on its inside, and an outer ring clamping portion 612 that, together with the shoulder portion 611, clamps the outer ring 640B of the second bearing 640 and is fixed to the second projection 610. With this configuration, the outer ring clamping portion 612 fixes the outer ring 640B of the second bearing 640 to the second projection 610, in other words, the second bearing 640 and the outer ring clamping portion 612 can be fixed to the fifth arm 225. Therefore, the fifth arm 225 can be made lighter compared to, for example, the case where the second bearing 640 and the outer ring clamping portion 612 are arranged on the sixth arm 226. Thus, the operational performance of the fifth arm 225 can be improved.

[0075] Furthermore, in the vertical articulated robot 1 of this embodiment, the fifth arm 225 has a second shaft portion 410 extending along the pivot axis J6, a second bevel gear portion 412 provided at one end 410a of the second shaft portion 410 and receiving force by meshing with the first bevel gear portion 312, and a connecting portion 411 provided at the other end 410b of the second shaft portion 410, and a second bevel gear 400 inserted into the second opening 120, and at least one third bearing 450 that rotatably supports the second shaft portion 410 with respect to the housing 100, and the sixth arm 226 preferably has a flange 500, a reduction gear 510 connected to the flange 500 and amplifying the received force to drive the flange 500, and a fitting member 520 inserted into the reduction gear 510 and detachably fitted to the connecting portion 411 of the second shaft portion 410.

[0076] With this configuration, since the second shaft portion 410 of the second bevel gear 400 is supported by the housing 100 via the third bearing 450, the second bevel gear 400 can be fixed to the housing 100 whether the reduction gear 510 is connected to the second bevel gear 400 or removed from the second bevel gear 400. Therefore, it becomes possible to adjust the backlash between the first bevel gear 300 and the second bevel gear 400, in other words, to adjust the tooth contact, and the gap between the first bevel gear 300 and the second bevel gear 400 can be prevented from becoming too large. This improves the operational performance of the fifth arm 225 and the sixth arm 226.

[0077] The following describes some variations of the embodiments described above.

[0078] As described above, the elastic member 720 is not limited to the configuration described above, but may also have the configurations shown in Figures 10A, 10B, and 10C.

[0079] As shown in Figure 10A, the modified elastic member 720A has four through holes 722A provided at equal intervals around the through hole 721A. The presence of the through holes 722A allows the elastic member 720 to absorb a portion of its movement when it is crushed.

[0080] As shown in Figure 10B, the modified elastic member 720B has four equally spaced notches around the through hole 721B that connect to the through hole 721B, in other words, radially recessed recesses 722B. The presence of the recesses 722B allows a portion of the moving elastic member 720 to be absorbed by the recesses 722B when the elastic member 720 is crushed.

[0081] As shown in Figure 10C, the modified elastic member 720C has four equally spaced notches connected to the outer circumference, or in other words, radially recessed recesses 722C, around the through hole 721C. The presence of the recesses 722C allows a portion of the moving elastic member 720 to be absorbed by the recesses 722C when the elastic member 720 is crushed.

[0082] As described above, the spacer 730 is not limited to the configuration described above, but may also be configured as shown in Figures 11A and 11B.

[0083] As shown in Figure 11A, the modified spacer 730A has four equally spaced notches around the through hole 731A that connect to the through hole 731A, in other words, radially recessed recesses 732A. The presence of the recesses 732A allows a portion of the moving elastic member 720 to be absorbed by the recesses 732A when the elastic member 720 is compressed.

[0084] As shown in Figure 11B, the modified spacer 730B has four equally spaced notches connected to the outer diameter, or in other words, radially recessed recesses 732B, around the through hole 731B. The presence of the recesses 732B allows a portion of the moving elastic member 720 to be absorbed by the recesses 732B when the elastic member 720 is compressed.

[0085] In addition, the retaining portion 710 may also be provided with through holes or recesses around the through hole 711, as in the modified example described above.

[0086] Thus, in the modified vertical articulated robot 1, through holes 721A, 721B, 721C, 731A, and 731B through which the first bevel gear 300 passes are provided at the center of the holding portion 710, the elastic member 720, and the spacer 730, and it is preferable that at least one of the holding portion 710, the elastic member 720, and the spacer 730 is provided with a through hole 722A or a radially recessed recess 722B, 722C, 732A, and 732B around the through holes 721A, 721B, 721C, 731A, and 731B. With this configuration, since through holes 722A and recesses 722B, 722C, 732A, and 732B are provided around the through holes 721A, 721B, 721C, 731A, and 731B through which the first bevel gear 300 passes, even if the elastic member 720 is crushed by pressing the pressing part 700, the crushed and moving part can be moved into the through holes 722A and recesses 722B, 722C, 732A, and 732B, thus preventing contact with the first bevel gear 300 located on the inside.

[0087] As described in the embodiments and modifications above, the holding portion 710, elastic member 720, and spacer 730 are not limited to having through holes 732, 722A or recesses 722B, 722C, 732A, 732B for absorbing a portion of the elastic member 720. For example, at least one of the holding portion 710, elastic member 720, and spacer 730 may have a thin portion around the through holes 711, 721, 731 that absorbs a portion of the elastic member 720. Also, the holding portion 710, elastic members 720A, 720B, 720C, and spacers 730A, 730B of the modifications may have a thin portion.

[0088] Thus, in the modified vertical articulated robot 1, through holes 721A, 721B, 721C, 731A, and 731B through which the first bevel gear 300 passes are provided at the center of the holding part 710, the elastic member 720, and the spacer 730, and it is preferable that at least one of the holding part 710, the elastic member 720, and the spacer 730 has a thin portion around the through holes 721A, 721B, 721C, 731A, and 731B through which the first bevel gear 300 passes. With this configuration, since a thin portion is provided around the through holes 721A, 721B, 721C, 731A, and 731B through which the first bevel gear 300 passes, even if the elastic member 720 is crushed by pressing the pressing part 700, the crushed portion can be moved to the thin portion, and contact with the first bevel gear 300 located on the inside can be suppressed.

[0089] As described above, the retaining portion 710 is not limited to being an annular shape with uniform thickness, but may also be configured as shown in Figures 12A and 12B. As shown in Figures 12A and 12B, in the modified retaining portion 710A, a flange 713A is provided at the inner diameter end 711A that is inclined toward the elastic member 720.

[0090] As described above, since the flange 713A is provided on the retaining portion 710A which is positioned on the elastic member 720, even if the elastic member 720 is crushed, it is possible to stop a portion of the crushed and moving elastic member 720, in other words, a portion of the protruding elastic member 720, with the flange 713A, thereby preventing it from coming into contact with the first bevel gear 300 which is positioned on the inside.

[0091] As described above, the spacer 730 is not limited to being an annular shape with uniform thickness, and may also be provided with a flange 713A that is inclined toward the elastic member 720, as in the retaining portion 710A of the modified example described above.

[0092] Thus, in the modified vertical articulated robot 1, it is preferable that the inner diameter end 711A of the holding portion 710 is provided with a flange 713A that is inclined toward the elastic member 720. With this configuration, since the flange 713A is provided on the holding portion 710A which is positioned on the elastic member 720, even if the elastic member 720 is crushed, it is possible to stop a part of the crushed and moving elastic member 720, in other words, a part of the protruding elastic member 720, with the flange 713A, thereby preventing contact with the first bevel gear 300 which is positioned on the inside.

[0093] Thus, in the modified vertical articulated robot 1, it is preferable that the inner diameter end 711A of the spacer 730 is provided with a flange 713A that is inclined toward the elastic member 720. With this configuration, since the flange 713A is provided on the spacer 730 which is positioned below the elastic member 720, even if the elastic member 720 is crushed, it is possible to stop a part of the crushed and moving elastic member 720, in other words, a part of the protruding elastic member 720, with the flange 713A, thereby preventing it from coming into contact with the first bevel gear 300 which is positioned on the inside.

[0094] As described above, the configuration of the first bevel gear 300, the second bevel gear 400, and the mating member 520 may be as shown in Figure 13.

[0095] Specifically, in the modified fifth arm 225A, the first bevel teeth 312A are provided at the tip of the first bevel gear 300A, i.e., in the +Z direction, and the fourth bearing 350C is positioned at the tip. The second bevel gear 400A has a hollow internal structure S. The second shaft portion 520A is provided with a through hole 521A, similar to the embodiment. That is, the internal structure S is hollow from the second shaft portion 520A to the second bevel gear 400A.

[0096] As described above, in the modified vertical articulated robot 1, the fifth arm 225A has a second bevel gear 400A having a second shaft portion 520A extending along the rotation axis J6 and a second bevel tooth portion 412A provided at one end of the second shaft portion 520A that receives force by meshing with the first bevel tooth portion 312A. The first bevel gear 300A has a fourth bearing 350C positioned at the tip of the first bevel tooth portion 312A, and the second bevel gear 400A preferably has a hollow structure. With this configuration, it is possible to reduce the weight of the fifth arm 225A and improve the operational performance of the fifth arm 225A and the sixth arm 226.

[0097] As described above, in addition to the fact that the pressing portion 700 is located on one end 310a of the first shaft portion 310 of the first bevel gear 300, the pressing portion 700A may also be located on the other end 410b of the second shaft portion 410 of the second bevel gear 400. That is, the pressing portion 700A is not limited to the input side of the first bevel gear 300, but is also located on the output side of the second bevel gear 400 (see Figures 3 and 9).

[0098] As described above, the outer ring clamping portion 612 that secures the outer ring 640B of the second bearing 640 is not limited to being arranged separately from the second projection 610, but may be provided integrally with the second projection 610. [Explanation of Symbols]

[0099] 1…Vertical articulated robot, 2…Robot body, 10…Controller, 21…Base, 22…Robot arm, 24…End effector, 31…Housing, 32…Cover, 41…Motor, 43…Pulley, 45…Power transmission belt, 61…Motor, 63…Pulley, 65…Power transmission belt, 100…Housing, 110…First opening as an opening, 111…Part, 120…Second opening, 221…First arm, 222…Second arm, 223…Third arm, 224…Fourth arm as a base arm member, 224a…Upper side Tip section, 224b...Lower tip section, 225, 225A...Fifth arm as first arm member, 226...Sixth arm as second arm member, 231...First drive mechanism, 232...Second drive mechanism, 233...Third drive mechanism, 234...Fourth drive mechanism, 235...Fifth drive mechanism, 236...Sixth drive mechanism, 300, 300A...First bevel gear as bevel gear, 310...First shaft section, 310a...One end, 310b...Other end, 311...Operating section, 312, 312A...First bevel tooth section, 350A1...Outer ring, 350A2...Inner ring, 400, 400A...Second bevel gear ,410...Second shaft portion, 410a...One end, 410b...Other end, 411...Connecting portion, 411a...Protrusion, 412,412A...Second bevel tooth portion, 420...Female thread portion, 500...Flange, 510...Reduction gear, 520...Fitting member, 520a...Recess, 520A...Second shaft portion, 521,521A...Through hole, 610...Second projection, 610a...Step portion, 611...Shoulder portion, 612...Outer ring clamping portion, 613...Fixing bolt as fixing screw, 620...First projection, 620a...Step portion, 640A...Inner ring, 640B...Outer ring, 700,700A...Pressing portion, 710...Holding Holding part, 710a...end part, 710A...retaining part, 710b...end part, 711, 721, 731...through hole as first through hole, 711A...end part, 712...through hole, 713A...flange, 720, 720A, 720B, 720C...elastic member, 720a, 720b...end part, 721A, 721B, 721C, 722A...through hole, 722B, 722C...recess, 730, 730A, 730B...spacer, 730a, 730b...end part, 731A...through hole, 731a...end part, 732...through hole as second through hole, 732A, 732B...recess.

Claims

1. A base arm member having a motor, A first arm member provided on the base arm member and rotating around the first axis, A second arm member is provided on the first arm member and rotates around a second axis that intersects the first axis, Equipped with, The first arm member is, A housing having a first projection that protrudes along the first axis and an opening provided inside the first projection, A bevel gear having a first shaft portion extending along the first axis, an operating portion provided at one end of the first shaft portion including a step or recess, and a first bevel tooth portion provided at the other end of the first shaft portion, which is inserted into the opening, A first bearing is provided, which is located within the opening and has an outer ring and an inner ring, and which rotatably supports the first shaft portion. The device comprises a retaining portion fixed to the first protrusion, an elastic member positioned between the retaining portion and the first bearing, and a pressing portion that presses the outer ring from the outside along the first axis, Equipped with, The operating section is a vertical articulated robot that protrudes outward from the first protruding section and the pressing section.

2. A vertical articulated robot according to claim 1, A vertical articulated robot in which the inner diameter end of the holding portion protrudes inward from the inner diameter end of the elastic member.

3. A vertical articulated robot according to claim 1, A vertical articulated robot is provided with a flange at the inner diameter end of the holding portion that is inclined toward the elastic member.

4. A vertical articulated robot according to claim 1, A vertical articulated robot in which a spacer is placed between the elastic member and the first bearing.

5. A vertical articulated robot according to claim 4, A vertical articulated robot in which the inner diameter end of the spacer protrudes further inward than the inner diameter end of the elastic member.

6. A vertical articulated robot according to claim 4, A vertical articulated robot is provided with a flange at the inner diameter end of the spacer that is inclined toward the elastic member.

7. A vertical articulated robot according to claim 1, The pressing portion has a fixing screw, A vertical articulated robot, wherein the outer surface of the holding part is provided with a hole through which the fixing screw passes.

8. A vertical articulated robot according to claim 4, The center of the holding portion, the elastic member, and the spacer is provided with a first through-hole through which the bevel gear passes. A vertical articulated robot in which at least one of the holding portion, the elastic member, and the spacer is provided with a second through hole or a radially recessed recess around the first through hole.

9. A vertical articulated robot according to claim 8, The first through-hole through which the bevel gear passes is provided in the center of the holding portion, the elastic member, and the spacer. A vertical articulated robot in which at least one of the holding portion, the elastic member, and the spacer has a thin portion around the first through hole.

10. A vertical articulated robot according to claim 1, The aforementioned base arm member is, A cylindrical second projection that protrudes along the first axis and has a shoulder on the inside, Together with the shoulder portion, the outer ring clamping portion sandwiches the outer ring of the second bearing and is fixed to the second protrusion, A vertical articulated robot.

11. A vertical articulated robot according to claim 1, The first arm member is, A second bevel gear having a second shaft portion extending along the second shaft, a second bevel tooth portion provided at one end of the second shaft portion and receiving force by meshing with the first bevel tooth portion, and a connecting portion provided at the other end of the second shaft portion, and inserted into the second opening, The housing includes at least one third bearing that rotatably supports the second shaft portion, The second arm member is, Flange and, A reduction gear connected to the flange, which amplifies the force it receives to drive the flange, A fitting member inserted into the reduction gear and detachably fitted to the connecting portion of the second shaft, A vertical articulated robot.

12. A vertical articulated robot according to claim 1, The first arm member is, A second bevel gear having a second shaft portion extending along the second shaft, and a second bevel tooth portion provided at one end of the second shaft portion, which receives force by meshing with the first bevel tooth portion, It has, The first bevel gear has a fourth bearing positioned at the tip of the first bevel tooth portion. The second bevel gear is a vertical articulated robot having a hollow structure.

Images