robot

Abstract

To provide a robot which can inhibit lubricant leaking from a rotation transmission mechanism from further leaking to the outside.SOLUTION: A robot 100 includes an annular lubricant storage part 80 which is disposed between a first seal member 71 and a second seal member 74 in a rotation axis CL direction of a rotary part 42 and stores lubricant leaking from a rotation transmission mechanism 40 so as to delay the lubricant reaching the second seal member 74.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] This disclosure relates to robots. [Background technology]

[0002] Conventionally, robots equipped with a rotation transmission mechanism disposed at a joint of a robot arm have been known. For example, Patent Document 1 discloses a robot equipped with a rotation transmission mechanism disposed at a joint of a robot arm, the rotation transmission mechanism including an annular first seal member that seals a lubricant therein, and an annular second seal member disposed outside the rotation transmission mechanism and outside the first seal member in the radial direction of a rotating part of the rotation transmission mechanism. In the robot described in Patent Document 1, when the rotation axis direction of the rotating part is horizontal, one end and the other end of the lubricant that passes through the first seal member are likely to immediately reach the second seal member via spaces adjacent to the first seal member and the second seal member, respectively. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-254787 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the robot described in Patent Document 1, the lubricant that has passed through the first seal member easily reaches the second seal member via the spaces adjacent to the first seal member and the second seal member at one end and the other end, respectively, so the lubricant that has leaked from the rotation transmission mechanism easily leaks further outward from the second seal member. For this reason, there is a demand for a robot that can prevent the lubricant that has leaked from the rotation transmission mechanism from leaking further outward.

[0005] This disclosure has been made to solve the above-mentioned problems, and one objective of this disclosure is to provide a robot that can prevent lubricant that has leaked from a rotation transmission mechanism from leaking further outward. [Means for solving the problem]

[0006] In order to achieve the above object, a robot according to one aspect of the present disclosure includes: a robot arm including a plurality of arm portions and joint portions connecting the arm portions; a rotation transmission mechanism disposed at the joint portion and including a fixed portion, a rotating portion that rotates relative to the fixed portion, and an annular first sealing member disposed between the fixed portion and the rotating portion and sealing a lubricant therein; an annular second sealing member disposed outside the rotation transmission mechanism and on one side of the first sealing member in the rotational axis direction of the rotating portion; and an annular lubricant storage portion disposed between the first sealing member and the second sealing member in the rotational axis direction of the rotating portion and storing lubricant so as to delay the lubricant leaking from the rotation transmission mechanism from reaching the second sealing member.

[0007] As described above, the robot according to one aspect of this disclosure includes an annular lubricant reservoir disposed between the first seal member and the second seal member in the rotation axis direction of the rotating unit, and configured to store lubricant so as to delay the lubricant leaking from the rotation transmission mechanism from reaching the second seal member. This allows the lubricant reservoir to store the lubricant leaking from the rotation transmission mechanism and delay its arrival at the second seal member. As a result, the lubricant leaking from the rotation transmission mechanism can be prevented from further leaking outward. [Effects of the Invention]

[0008] According to the present disclosure, as described above, it is possible to provide a robot that can prevent lubricant that has leaked from the rotation transmission mechanism from further leaking outward. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view illustrating a robot according to an embodiment of the present disclosure. [Figure 2]FIG. 1 is a cross-sectional view showing a joint portion of a robot according to an embodiment of the present disclosure. [Figure 3] FIG. 3 is an enlarged view of a portion III in FIG. 2. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments embodying the present disclosure will be described with reference to the drawings.

[0011] The configuration of a robot 100 according to an embodiment of the present disclosure will be described with reference to FIGS. 1 to 3.

[0012] (Overall robot configuration) As shown in Fig. 1, the robot 100 is a vertical articulated robot. The robot 100 includes a robot arm 10 and a base 20 that supports the robot arm 10. The robot arm 10 includes a plurality of arm sections 11 and joint sections 12 that connect the arm sections 11 to each other. An end effector is attached to the tip of the robot arm 10.

[0013] As shown in Fig. 2, the robot 100 includes a motor 30 and a rotation transmission mechanism 40 connected to an output shaft 31 of the motor 30. The rotation transmission mechanism 40 is disposed in the joint unit 12. Note that A, A1, A2, R, R1, and R2 in the figure respectively indicate the direction of a rotation axis CL of a rotating unit 42 (described later), one side in the direction of the rotation axis CL, the other side in the direction of the rotation axis CL, the radial direction of the rotating unit 42, the inner side in the radial direction of the rotating unit 42, and the outer side in the radial direction of the rotating unit 42. Note that Fig. 2 shows a state in which the robot arm 10 is disposed so that the direction of the rotation axis CL of the rotating unit 42 is horizontal.

[0014] (Configuration of motor and rotation transmission mechanism) As shown in FIG. 2 , the motor 30 and the rotation transmission mechanism 40 are provided to rotate a first arm 11A, which is one of two arm units 11 adjacent to each other via a joint 12 and is located at the base end of the robot arm 10, relative to a second arm unit 11B, which is one of two arm units 11 adjacent to each other via a joint 12 and is located at the tip end of the robot arm 10. Specifically, the rotation transmission mechanism 40 includes a shaft 41, a gear unit (not shown), a rotating unit 42, and a fixed unit 43. One end of the rotating unit 42 of the shaft 41 in the direction of the rotation axis CL is fixed to the output shaft 31 of the motor 30. The other end of the rotating unit 42 of the shaft 41 in the direction of the rotation axis CL is connected to the gear unit. The gear unit is connected to the rotating unit 42. The rotational driving force of the motor 30 is transmitted to the rotating unit 42 via the output shaft 31, the shaft 41, and the gear unit of the motor 30. The rotating unit 42 rotates relative to the fixed unit 43. Rotating portion 42 is fixed to second arm portion 11B and a rotating member 62 (described later) by fastening members 51. Fixed portion 43 is fixed to first arm portion 11A and a housing member 61 (described later) by fastening members 52. Note that rotation transmission mechanism 40 is a reducer.

[0015] The rotation transmission mechanism 40 is disposed on the other side of the rotating unit 42 in the direction of the rotation axis CL relative to the motor 30. The shaft 41 is disposed coaxially with the output shaft 31 of the motor 30. The rotating unit 42 is disposed radially outward of the rotating unit 42 relative to the shaft 41. The fixed unit 43 is disposed radially outward of the rotating unit 42 relative to the rotating unit 42. An end 11Ba of the second arm unit 11B on the first arm unit 11A side is disposed between the rotation transmission mechanism 40 and the motor 30.

[0016] The robot 100 includes an annular rotating member 62 disposed between the end 11Ba of the second arm unit 11B on the first arm unit 11A side and the rotating unit 42 of the rotation transmission mechanism 40 in the direction of the rotation axis CL of the rotating unit 42, and with its inner peripheral surface facing the outer peripheral surface of the shaft 41. As described above, the rotating member 62 is fixed to the second arm unit 11B and the rotating unit 42 of the rotation transmission mechanism 40. Therefore, the rotating member 62 rotates together with the second arm unit 11B relative to the first arm unit 11A.

[0017] (Structure for sealing lubricant) 2, a lubricant for lubricating the meshing of the gears in the gear portion is filled inside the rotation transmission mechanism 40. The robot 100 includes a structure for sealing in the lubricant, which includes an annular first seal member 71, an annular first arm portion O-ring 72, and a rotating member seal member 73.

[0018] The first seal member 71 is disposed between the fixed portion 43 and the rotating portion 42. The first seal member 71 prevents the lubricant inside the rotation transmission mechanism 40 from leaking from between the fixed portion 43 and the rotating portion 42 to the outside of the rotation transmission mechanism 40. The first seal member 71 includes a lip portion formed on the inside of the first seal member 71 in the radial direction of the rotating portion 42.

[0019] The first arm portion O-ring 72 is disposed between the end of the first arm portion 11A on the second arm portion 11B side and the fixed portion 43 of the rotation transmission mechanism 40. The first arm portion O-ring 72 prevents the lubricant inside the rotation transmission mechanism 40 from leaking out of the joint portion 12 from between the end of the first arm portion 11A on the second arm portion 11B side and the fixed portion 43 of the rotation transmission mechanism 40.

[0020] The rotating member sealing member 73 is disposed between the outer circumferential surface of one end of the rotating portion 42 of the shaft 41 in the direction of the rotation axis CL and the inner circumferential surface of an opening formed in the end 11Ba of the second arm portion 11B on the first arm portion 11A side. The rotating member sealing member 73 prevents the lubricant inside the rotation transmission mechanism 40 from leaking from between the outer circumferential surface of the one end of the rotating portion 42 of the shaft 41 in the direction of the rotation axis CL and the inner circumferential surface of the opening formed in the end 11Ba of the second arm portion 11B on the first arm portion 11A side into the space in which the motor 30 of the joint portion 12 is disposed. The rotating member sealing member 73 includes a lip portion disposed radially inward of the rotating portion 42 of the rotating member sealing member 73.

[0021] As shown in FIG. 3 , the robot 100 includes a structure for preventing lubricant leaking from the rotation-transmitting mechanism 40 through the portion between the fixed portion 43 and the rotating portion 42 where the first seal member 71 is disposed, i.e., a structure for sealing off the leakage of lubricant to the outside of the joint portion 12. The structure includes an annular housing member 61, the above-described annular rotating member 62, an annular second seal member 74, and an annular housing member O-ring 75. The housing member 61, the rotating member 62, the second seal member 74, and the housing member O-ring 75 are disposed outside the rotation-transmitting mechanism 40. The housing member 61 is disposed outside the rotation-transmitting mechanism 40 to form a lubricant reservoir 80 (described later). The first seal member 71 includes a lip portion formed on the first seal member 71 radially inward of the rotating portion 42.

[0022] A portion of the housing member 61 on the other side in the direction of the rotation axis CL of the rotating portion 42 is disposed radially outward of the rotating portion 42 with respect to the fixed portion 43 of the rotation transmission mechanism 40. A portion of the housing member 61 on one side in the direction of the rotation axis CL of the rotating portion 42 faces, in the radial direction of the rotating portion 42, one end of the rotating portion 42 of the rotation transmission mechanism 40 on one side in the direction of the rotation axis CL of the rotating portion 42, and the rotating member 62. The second seal member 74 is disposed on one side of the first seal member 71 in the direction of the rotation axis CL of the rotating portion 42. The second seal member 74 includes a lip portion formed on the inner side of the rotating portion 42 in the radial direction of the rotating portion 42. The second seal member 74 is disposed radially of the rotating portion 42 between the rotating member 62 and the end of the rotating portion 42 of the housing member 61 on one side in the direction of the rotation axis CL of the rotating portion 42. The rotating member 62 has an outer peripheral surface 62a that contacts an inner peripheral surface 74a of the second seal member 74. One end of the housing member 61 in the direction of the rotation axis CL of the rotating portion 42 has an inner circumferential surface that comes into contact with the outer circumferential surface of the second seal member 74.

[0023] The lubricant reservoir 80 is an annular space that stores lubricant leaked from the rotation transmission mechanism 40 through a portion between the fixed part 43 and the rotating part 42 where the first seal member 71 is disposed, and is configured by an end of the fixed part 43 of the rotation transmission mechanism 40 on one side in the direction of the rotation axis CL of the rotating part 42, a portion of the housing member 61 on one side in the direction of the rotation axis CL of the rotating part 42, the second seal member 74, the rotating member 62, and an end of the rotating part 42 of the rotation transmission mechanism 40 on one side in the direction of the rotation axis CL of the rotating part 42. That is, the robot 100 includes the annular lubricant reservoir 80 that is disposed between the first seal member 71 and the second seal member 74 in the direction of the rotation axis CL of the rotating part 42 and stores lubricant leaked from the rotation transmission mechanism 40 through a portion between the fixed part 43 and the rotating part 42 where the first seal member 71 is disposed.

[0024] The housing member O-ring 75 is disposed between one end of the rotating part 42 of the rotation transmission mechanism 40 in the direction of the rotation axis CL of the rotating part 42 and a portion of the housing member 61 on the other side in the direction of the rotation axis CL of the rotating part 42. The housing member O-ring 75 prevents the lubricant stored in the lubricant reservoir 80 from leaking out of the joint portion 12 from between the one end of the rotating part 42 of the rotation transmission mechanism 40 in the direction of the rotation axis CL of the rotating part 42 and the portion of the housing member 61 on the other side in the direction of the rotation axis CL of the rotating part 42.

[0025] (Configuration of lubricant reservoir) 3, the second seal member 74 includes a lip portion formed on the inner side of the rotating portion 42 of the second seal member 74 in the radial direction. The lubricant reservoir 80 is connected to the lubricant reservoir 80 and includes a lubricant discharge hole 61a that is normally closed and is opened when the lubricant stored in the lubricant reservoir 80 is to be discharged from the lubricant reservoir 80. The lubricant discharge hole 61a is normally closed by a sealing plug 76, and when the lubricant stored in the lubricant reservoir 80 is to be discharged from the lubricant reservoir 80, the sealing plug 76 is removed from the lubricant discharge hole 61a. The lubricant discharge hole 61a is formed in the housing member 61.

[0026] The lubricant discharge hole 61a is disposed at a position that corresponds to the lower end 80a of the annular lubricant reservoir 80 when the direction of the rotation axis CL of the rotating part 42 is horizontal. Specifically, the lubricant discharge hole 61a is formed in a portion of the outer surface 80b of the lubricant reservoir 80 in the radial direction of the rotating part 42, which corresponds to the bottom surface of the lubricant reservoir 80 when the direction of the rotation axis CL of the rotating part 42 is horizontal. Note that a plurality of the lubricant discharge holes 61a are disposed at equal intervals in the radial direction of the rotating part 42. In other words, the lubricant discharge holes 61a are also formed in a portion of the outer surface 80b of the lubricant reservoir 80 in the radial direction of the rotating part 42, other than the portion that corresponds to the bottom surface of the lubricant reservoir 80 when the direction of the rotation axis CL of the rotating part 42 is horizontal.

[0027] <Structure for delaying the arrival of lubricant leaking from the rotation transmission mechanism at the second seal member> The lubricant reservoir 80 stores the lubricant so as to delay the lubricant leaking from the rotation transmission mechanism 40 from reaching the second seal member 74.

[0028] As a first structure for delaying the arrival of lubricant leaking from the rotation transmission mechanism 40 at the second seal member 74, the lubricant reservoir 80 includes an annular partition wall 80d that protrudes to cover a portion 74b of the second seal member 74 on the first seal member 71 side. Specifically, an annular partition wall 80d that protrudes from the outside toward the inside in the radial direction of the rotating portion 42 is formed on an outer surface 80b of the lubricant reservoir 80 in the radial direction of the rotating portion 42 so as to cover an inner portion of the second seal member 74 in the direction of the rotation axis CL of the rotating portion 42. The partition wall 80d protrudes from the outside toward the inside in the radial direction of the rotating portion 42 from the outer surface 80b of the lubricant reservoir 80 in the radial direction of the rotating portion 42 so as to cover, for example, half of an inner portion of the second seal member 74 in the radial direction of the rotating portion 42.

[0029] As a second structure for delaying the arrival of lubricant leaking from the rotation transmission mechanism 40 at the second seal member 74, a surface 80c that serves as the bottom surface of the lubricant storage portion 80 when the direction of the rotation axis CL of the rotating portion 42 of the lubricant storage portion 80 is horizontal is inclined from the side of surface 80c that serves as the bottom surface of the lubricant storage portion 80 to the opposite side from surface 80c that serves as the bottom surface of the lubricant storage portion 80, as it moves from the first seal member 71 side to the second seal member 74 side in the direction of the rotation axis CL of the rotating portion 42. Specifically, a surface 80b that is on the outer side in the radial direction of the rotating portion 42 of the lubricant storage portion 80 is inclined from the outer side to the inner side in the radial direction of the rotating portion 42, as it moves from the first seal member 71 side to the second seal member 74 side in the direction of the rotation axis CL of the rotating portion 42. When the direction of the rotation axis CL of the rotating part 42 of the lubricant storage part 80 is horizontal, the outer surface 80b of the lubricant storage part 80 in the radial direction of the rotating part 42 is inclined from bottom to top in the vertical direction as it moves from the first seal member 71 side to the second seal member 74 side. Note that the lubricant discharge hole 61a is formed at a position closer to the first seal member 71 than the second seal member 74 on a surface 80c that serves as the bottom surface of the lubricant storage part 80 when the direction of the rotation axis CL of the rotating part 42 of the lubricant storage part 80 is horizontal.

[0030] (Size of the second seal member relative to the first seal member) In the direction of the rotation axis CL of the rotating part 42, the width W2 of the second seal member 74 is smaller than the width W1 of the first seal member 71. In other words, the area where the inner circumferential surface 74a of the second seal member 74 contacts the outer circumferential surface 62a of the rotating member 62 is smaller than the area where the inner circumferential surface of the first seal member 71 contacts the rotating part 42 of the rotation transmission mechanism 40.

[0031] An inner diameter r2 of the second seal member 74 is smaller than an inner diameter r1 of the first seal member 71. That is, in the radial direction of the rotating part 42, the position where the inner circumferential surface 74a of the second seal member 74 contacts the outer circumferential surface 62a of the rotating member 62 is inside of the position where the inner circumferential surface of the first seal member 71 contacts the rotating part 42 of the rotation transmission mechanism 40. Note that in the radial direction of the rotating part 42, the position of the outer circumferential surface of the second seal member 74 is outside the position of the inner circumferential surface of the first seal member 71.

[0032] (Effects of this embodiment) In this embodiment, the following effects can be obtained.

[0033] In this embodiment, the robot 100 includes an annular lubricant reservoir 80 that is disposed between the first seal member 71 and the second seal member 74 in the direction of the rotation axis CL of the rotating part 42 and that stores the lubricant so as to delay the lubricant leaking from the rotation transmission mechanism 40 from reaching the second seal member 74. This allows the lubricant reservoir 80 to store the lubricant leaking from the rotation transmission mechanism 40 and delay its arrival at the second seal member 74. As a result, the lubricant leaking from the rotation transmission mechanism 40 can be prevented from leaking further outward.

[0034] Furthermore, in this embodiment, the lubricant reservoir 80 includes an annular partition wall 80d that protrudes so as to cover a portion 74b of the second seal member 74 on the first seal member 71 side. This allows the annular partition wall 80d to prevent the lubricant stored in the lubricant reservoir 80 from reaching the second seal member 74. As a result, it is possible to easily configure the annular lubricant reservoir 80 that stores the lubricant so as to delay the lubricant leaking from the rotation transmission mechanism 40 from reaching the second seal member 74.

[0035] Furthermore, in the present embodiment, the surface 80c of the lubricant reservoir 80, which serves as the bottom surface of the lubricant reservoir 80 when the direction of the rotation axis CL of the rotating part 42 is horizontal, is inclined toward the rotation axis CL as it moves from the first seal member 71 side toward the second seal member 74 side in the direction of the rotation axis CL of the rotating part 42. As a result, when the direction of the rotation axis CL of the rotating part 42 is horizontal, the inclination of the surface 80c, which serves as the bottom surface of the annular lubricant reservoir 80, can prevent the lubricant stored in the lubricant reservoir 80 from reaching the second seal member 74. As a result, it is possible to easily configure the annular lubricant reservoir 80, which stores the lubricant so as to delay the lubricant leaking from the rotation transmission mechanism 40 from reaching the second seal member 74.

[0036] Furthermore, in this embodiment, the robot 100 is provided with a lubricant discharge hole 61a that is connected to the lubricant storage unit 80, is normally closed, and is opened when the lubricant stored in the lubricant storage unit 80 is to be discharged from the lubricant storage unit 80. Thus, by opening the lubricant discharge hole 61a, the lubricant stored in the lubricant storage unit 80 can be discharged from the lubricant storage unit 80.

[0037] Furthermore, in this embodiment, the robot 100 includes an annular housing member 61 that is disposed outside the rotation transmission mechanism 40 to form the lubricant reservoir 80 and that has the lubricant discharge hole 61a formed therein. As a result, the housing member 61 functions to form the lubricant reservoir 80 and also functions as the member in which the lubricant discharge hole 61a is formed. Therefore, the number of parts in the robot 100 can be reduced compared to when the robot 100 is provided with separate members that form the lubricant reservoir 80 and members in which the lubricant discharge hole 61a is formed.

[0038] Furthermore, in this embodiment, when the direction of the rotation axis CL of the rotating part 42 is horizontal, the lubricant discharge hole 61a is disposed at a position that corresponds to the lower end of the annular lubricant reservoir 80. As a result, when the direction of the rotation axis CL of the rotating part 42 is horizontal, the lubricant stored in the lubricant reservoir 80 can be discharged from the lubricant reservoir 80 by opening the lubricant discharge hole 61a.

[0039] Furthermore, in the present embodiment, when the direction of the rotation axis CL of the rotating part 42 of the lubricant storage part 80 is horizontal, the surface 80c that serves as the bottom surface of the lubricant storage part 80 is inclined toward the rotation axis CL as it moves from the first seal member 71 side toward the second seal member 74 side. The lubricant discharge hole 61a is formed at a position on the surface 80c that serves as the bottom surface of the lubricant storage part 80 when the direction of the rotation axis CL of the rotating part 42 of the lubricant storage part 80 is horizontal, closer to the first seal member 71 than to the second seal member 74. This allows the lubricant discharge hole 61a to be positioned in a lower portion of the surface 80c that serves as the bottom surface of the lubricant storage part 80 in the vertical direction when the direction of the rotation axis CL of the rotating part 42 is horizontal. As a result, when the direction of the rotation axis CL of the rotating part 42 is horizontal, even if the amount of lubricant stored in the lubricant storage part 80 is relatively small, the lubricant stored in the lubricant storage part 80 can be discharged from the lubricant storage part 80 by opening the lubricant discharge hole 61a.

[0040] In this embodiment, the robot 100 includes a rotating member 62 that is fixed to the rotating unit 42 and has an outer circumferential surface 62a that contacts an inner circumferential surface 74a of the second seal member 74. The width W2 of the second seal member 74 in the direction of the rotation axis CL of the rotating unit 42 is smaller than the width W1 of the first seal member 71. This relatively reduces the contact area between the inner circumferential surface 74a of the second seal member 74 and the outer circumferential surface 62a of the rotating member 62. This reduces frictional resistance that occurs between the outer circumferential surface 62a of the rotating member 62 and the inner circumferential surface 74a of the second seal member 74 when the rotating member 62 rotates relative to the second seal member 74. As a result, the loss of energy required to rotate the rotating unit 42 relative to the fixed unit 43 in the rotation transmission mechanism 40 can be reduced.

[0041] In this embodiment, the robot 100 includes an annular rotating member 62 that is fixed to the rotating unit 42 and has an outer peripheral surface 62a that contacts the inner peripheral surface 74a of the second seal member 74. The inner diameter r2 of the second seal member 74 is smaller than the inner diameter r1 of the first seal member 71. This reduces the moment acting on the portion of the outer peripheral surface 62a of the rotating member 62 that contacts the inner peripheral surface 74a of the second seal member 74, thereby reducing the frictional resistance that occurs between the outer peripheral surface 62a of the rotating member 62 and the inner peripheral surface 74a of the second seal member 74 when the rotating member 62 rotates relative to the second seal member 74. As a result, the loss of energy required to rotate the rotating unit 42 relative to the fixed unit 43 in the rotation transmission mechanism 40 can be reduced.

[0042] Furthermore, in this embodiment, the second seal member 74 seals off the leakage of lubricant to the outside of the joint portion 12. This allows the lubricant reservoir 80 to delay the lubricant leaking from the rotation transmission mechanism 40 from reaching the second seal member 74, which stores the lubricant and seals off the leakage of the lubricant to the outside of the joint portion 12. As a result, it is possible to prevent the lubricant leaking from the rotation transmission mechanism 40 from leaking to the outside of the joint portion 12.

[0043] In this embodiment, the rotation transmission mechanism 40 is a reducer. This allows the lubricant reservoir 80 to store lubricant that has leaked from the reducer serving as the rotation transmission mechanism 40, and delay its arrival at the second seal member 74. As a result, it is possible to prevent the lubricant that has leaked from the reducer serving as the rotation transmission mechanism 40 from further leaking outward.

[0044] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the claims, not by the description of the above embodiments, and further includes all modifications (variations) within the meaning and scope equivalent to the claims.

[0045] For example, in the above embodiment, an example was shown in which the lubricant reservoir 80 includes the annular partition wall portion 80d that protrudes to cover the portion 74b of the second seal member 74 that faces the first seal member 71, but the present disclosure is not limited to this. In the present disclosure, the lubricant reservoir does not have to include the annular partition wall portion that protrudes to cover the portion of the second seal member that faces the first seal member.

[0046] In the above embodiment, the surface 80c that serves as the bottom surface of the lubricant storage portion 80 when the rotation axis CL of the rotating portion 42 of the lubricant storage portion 80 is horizontally inclined toward the rotation axis CL as it moves from the first seal member 71 toward the second seal member 74. However, the present disclosure is not limited to this. In the present disclosure, the surface that serves as the bottom surface of the lubricant storage portion when the rotation axis of the rotating portion of the lubricant storage portion is horizontally inclined does not have to be inclined from the first seal member toward the second seal member, or may be inclined toward the side opposite the rotation axis. Furthermore, the surface that serves as the bottom surface of the lubricant storage portion when the rotation axis of the rotating portion of the lubricant storage portion is horizontally inclined may be stepped.

[0047] Furthermore, in the above embodiment, an example has been described in which the robot 100 is connected to the lubricant reservoir 80, is normally closed, and is provided with the lubricant discharge hole 61a that is opened when the lubricant stored in the lubricant reservoir 80 is discharged from the lubricant reservoir 80, but the present disclosure is not limited to this. In the present disclosure, the robot may be connected to the lubricant reservoir, is always open, and is provided with a lubricant discharge hole that discharges the lubricant stored in the lubricant reservoir from the lubricant reservoir. Furthermore, the robot does not have to be connected to the lubricant reservoir and is provided with a lubricant discharge hole that discharges the lubricant stored in the lubricant reservoir from the lubricant reservoir.

[0048] In the above embodiment, the robot 100 is disposed outside the rotation transmission mechanism 40 to form the lubricant reservoir 80, and includes the annular housing member 61 in which the lubricant discharge hole 61a is formed. However, the present disclosure is not limited to this. In the present disclosure, the robot may separately include a member that forms the lubricant reservoir and a member in which the lubricant discharge hole is formed.

[0049] In addition, in the above embodiment, an example has been shown in which the lubricant discharge hole 61a is arranged at a position that corresponds to the lower end of the annular lubricant reservoir 80 when the direction of the rotation axis CL of the rotating part 42 is horizontal, but the present disclosure is not limited to this. In the present disclosure, the lubricant discharge hole does not have to be arranged at a position that corresponds to the lower end of the annular lubricant reservoir when the direction of the rotation axis of the rotating part is horizontal.

[0050] In addition, in the above embodiment, an example is shown in which the surface 80c that becomes the bottom surface of the lubricant storage section 80 when the direction of the rotation axis CL of the rotating part 42 of the lubricant storage section 80 is horizontally inclined toward the rotation axis CL as it moves from the first seal member 71 side toward the second seal member 74 side, and the lubricant discharge hole 61a is formed at a position closer to the first seal member 71 than the second seal member 74 on the surface 80c that becomes the bottom surface of the lubricant storage section 80 when the direction of the rotation axis CL of the rotating part 42 of the lubricant storage section 80 is horizontally inclined. However, the present disclosure is not limited to this. In the present disclosure, when the rotation axis direction of the rotating part of the lubricant storage portion is along the horizontal direction, the surface that becomes the bottom of the lubricant storage portion is inclined toward the rotation axis side as it moves from the first seal member side to the second seal member side, and the lubricant discharge hole may be formed in the center between the first seal member and the second seal member, or at a position closer to the second seal member than the first seal member, on the surface that becomes the bottom of the lubricant storage portion when the rotation axis direction of the rotating part of the lubricant storage portion is along the horizontal direction.

[0051] In addition, in the above embodiment, an example was shown in which the width W2 of the second seal member 74 is smaller than the width W1 of the first seal member 71 in the direction of the rotation axis CL of the rotating part 42, but the present disclosure is not limited to this. In the present disclosure, the width of the second seal member in the direction of the rotation axis CL of the rotating part may be equal to the width of the first seal member or may be larger than the width of the first seal member.

[0052] In addition, in the above embodiment, an example was shown in which the inner diameter r2 of the second seal member 74 is smaller than the inner diameter r1 of the first seal member 71, but the present disclosure is not limited to this. In the present disclosure, the inner diameter of the second seal member may be equal to or larger than the inner diameter of the first seal member.

[0053] In addition, in the above embodiment, an example has been shown in which the second seal member 74 prevents leakage of lubricant to the outside of the joint portion 12, but the present disclosure is not limited to this. In the present disclosure, the second seal member may also prevent leakage of lubricant from the inner portion to the outer portion inside the joint portion.

[0054] In addition, in the above embodiment, an example was shown in which the rotation transmission mechanism 40 was a speed reducer, but the present disclosure is not limited to this. In the present disclosure, the rotation transmission mechanism may be a speed increaser or a transmission.

[0055] In addition, in the above embodiment, an example has been shown in which the outer peripheral surface of the second seal member 74 is located outside the inner peripheral surface of the first seal member 71 in the radial direction of the rotating part 42, but the present disclosure is not limited to this. In the present disclosure, the outer peripheral surface of the second seal member may be located inside the inner peripheral surface of the first seal member in the radial direction of the rotating part.

[0056] Furthermore, in the above embodiment, an example has been shown in which a plurality of lubricant discharge holes 61a are arranged at equal intervals from one another in the radial direction of the rotating part 42, but the present disclosure is not limited to this. In the present disclosure, a plurality of lubricant discharge holes may be arranged at unequal intervals from one another in the radial direction of the rotating part, or a plurality of lubricant discharge holes may not be arranged.

[0057] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, special-purpose processors, integrated circuits, application-specific integrated circuits (ASICs), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuitry. In this disclosure, a circuit, unit, or means is hardware that performs the recited functions or hardware that is programmed to perform the recited functions. The hardware may be hardware disclosed herein or other known hardware that is programmed or configured to perform the recited functions. Where the hardware is a processor, which is considered a type of circuit, the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or processor.

[0058] [Aspect] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0059] (Aspect 1) a robot arm including a plurality of arm portions and joint portions connecting the arm portions; a rotation transmission mechanism that is disposed at the joint portion and includes a fixed portion, a rotating portion that rotates around a rotation axis relative to the fixed portion, and a first annular seal member that is disposed between the fixed portion and the rotating portion and seals a lubricant therein; a second annular seal member disposed outside the rotation transmission mechanism and on one side of the first seal member in the direction of the rotation axis of the rotating part; a ring-shaped lubricant reservoir disposed between the first seal member and the second seal member in the direction of the rotation axis of the rotating part, the ring-shaped lubricant reservoir configured to store the lubricant so as to delay the lubricant leaking from the rotation transmission mechanism from reaching the second seal member.

[0060] (Aspect 2) 2. The robot according to claim 1, wherein the lubricant reservoir includes an annular partition wall that protrudes to cover a portion of the second seal member on the first seal member side.

[0061] (Aspect 3) A robot described in aspect 1 or aspect 2, wherein when the rotation axis direction of the rotating part of the lubricant storage section is along the horizontal direction, the surface that becomes the bottom surface of the lubricant storage section is inclined toward the rotation axis side as it moves from the first seal member side to the second seal member side.

[0062] (Aspect 4) The robot of aspect 1 further comprises a lubricant discharge hole connected to the lubricant reservoir, which is normally closed and which is opened when the lubricant stored in the lubricant reservoir is to be discharged from the lubricant reservoir.

[0063] (Aspect 5) A robot according to aspect 4, comprising an annular housing member arranged outside the rotation transmission mechanism to form the lubricant reservoir, and having the lubricant discharge hole formed therein.

[0064] (Aspect 6) A robot described in aspect 4 or aspect 5, wherein the lubricant discharge hole is located at the lower end of the annular lubricant storage portion when the rotation axis direction of the rotating portion is along the horizontal direction.

[0065] (Aspect 7) a surface of the lubricant reservoir that serves as a bottom surface of the lubricant reservoir when the rotation axis direction of the rotating part is along a horizontal direction is inclined toward the rotation axis side from the first seal member side toward the second seal member side, A robot as described in aspect 6, wherein the lubricant discharge hole is formed at a position closer to the first seal member than the second seal member on a surface of the lubricant storage portion that becomes the bottom surface of the lubricant storage portion when the rotation axis direction of the rotating portion is along a horizontal direction.

[0066] (Aspect 8) a rotating member fixed to the rotating portion and having an outer circumferential surface in contact with an inner circumferential surface of the second seal member; Aspect 8. The robot according to any one of aspects 1 to 7, wherein the width of the second seal member in the direction of the rotation axis of the rotating part is smaller than the width of the first seal member.

[0067] (Aspect 9) an annular rotating member fixed to the rotating portion and having an outer circumferential surface in contact with an inner circumferential surface of the second seal member; Aspect 1. The robot according to any one of aspects 1 to 8, wherein the inner diameter of the second seal member is smaller than the inner diameter of the first seal member.

[0068] (Aspect 10) The robot according to any one of aspects 1 to 9, wherein the second seal member seals off leakage of the lubricant to the outside of the joint portion.

[0069] (Aspect 11) The robot according to any one of aspects 1 to 10, wherein the rotation transmission mechanism is a reducer. [Explanation of symbols]

[0070] 10 Robotic Arm 11 Arm section 12 Joints 40 Rotation transmission mechanism 42 Rotating part 43 Fixed part 61 Housing member 61a Lubricant discharge hole 62 Rotating member 62a (rotating member) outer surface 71 first seal member 74 Second seal member 74a (of the second seal member) inner peripheral surface 74b (part of the second seal member on the first seal member side) 80 Lubricant reservoir 80a Lower end (of lubricant reservoir) Surface 80c (which becomes the bottom surface of the lubricant reservoir when the rotation axis direction of the rotating part of the lubricant reservoir is along the horizontal direction) 80d Bulkhead 100 robots CL (rotating part) rotation axis r1 (first seal member) inner diameter r2 (second seal member) inner diameter W1 (width of the first seal member in the direction of the rotation axis of the rotating part) W2 (width of the second seal member in the direction of the rotation axis of the rotating part)

Claims

1. a robot arm including a plurality of arm portions and joint portions connecting the arm portions; a rotation transmission mechanism that is disposed at the joint portion and includes a fixed portion, a rotating portion that rotates around a rotation axis relative to the fixed portion, and a first annular seal member that is disposed between the fixed portion and the rotating portion and seals a lubricant therein; a second annular seal member disposed outside the rotation transmission mechanism and on one side of the first seal member in the direction of the rotation axis of the rotating part; a ring-shaped lubricant reservoir disposed between the first seal member and the second seal member in the direction of the rotation axis of the rotating part, the ring-shaped lubricant reservoir configured to store the lubricant so as to delay the lubricant leaking from the rotation transmission mechanism from reaching the second seal member.

2. The robot according to claim 1 , wherein the lubricant reservoir includes an annular partition wall portion that protrudes so as to cover a portion of the second seal member that faces the first seal member.

3. 2. The robot according to claim 1, wherein a surface of the lubricant storage portion that becomes a bottom surface of the lubricant storage portion when the rotation axis direction of the rotating part of the lubricant storage portion is a surface that is inclined toward the rotation axis side as it moves from the first seal member side to the second seal member side.

4. 2. The robot according to claim 1, further comprising a lubricant discharge hole connected to the lubricant reservoir, which is normally closed and which is opened when the lubricant stored in the lubricant reservoir is to be discharged from the lubricant reservoir.

5. The robot according to claim 4 , further comprising an annular housing member that is disposed outside the rotation transmission mechanism to form the lubricant reservoir, and in which the lubricant discharge hole is formed.

6. The robot according to claim 4 , wherein the lubricant discharge hole is disposed at a lower end of the annular lubricant reservoir when the rotation axis direction of the rotating part is a horizontal direction.

7. a surface of the lubricant reservoir that serves as a bottom surface of the lubricant reservoir when the rotation axis direction of the rotating part is a direction along a horizontal direction is inclined toward the rotation axis side from the first seal member side toward the second seal member side, 7. The robot according to claim 6, wherein the lubricant discharge hole is formed at a position closer to the first seal member than to the second seal member on a surface of the lubricant storage portion that becomes the bottom surface of the lubricant storage portion when the rotation axis direction of the rotating portion is along a horizontal direction.

8. a rotating member fixed to the rotating portion and having an outer circumferential surface in contact with an inner circumferential surface of the second seal member; The robot according to claim 1 , wherein a width of the second seal member in the direction of the rotation axis of the rotating part is smaller than a width of the first seal member.

9. an annular rotating member fixed to the rotating portion and having an outer circumferential surface in contact with an inner circumferential surface of the second seal member; The robot according to claim 1 , wherein an inner diameter of the second seal member is smaller than an inner diameter of the first seal member.

10. The robot according to claim 1 , wherein the second seal member seals the lubricant from leaking out of the joint portion.

11. The robot according to claim 1 , wherein the rotation transmission mechanism is a reducer.

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