CN118401353A - Joint robot - Google Patents

Abstract

The joint robot includes: a robot arm having a plurality of arms and a joint section rotatably connecting the plurality of arms; a housing portion provided inside the joint portion, having an opening in a side surface of the joint portion, and housing a motor as a driving source of the robot arm; and a cover body closing the opening of the accommodating portion. The cover has an engaging portion, the housing portion has an engaged portion, and the cover is attached to the housing portion so as to close the opening based on the engaging portion being engaged with the engaged portion. The engaging portion has an engaging claw which engages with the engaged portion and which cannot be disengaged from the engaged portion.

Description

Joint robot

Technical Field

The present invention relates to an articulated robot including a robot arm having an articulated portion for rotatably connecting a plurality of arms.

Background

The mechanical arm having the joint portion has the following structure: the motor and the decelerator as a power source of the mechanical arm are accommodated in an accommodating portion provided in the joint portion. In consideration of the assembling workability of the mechanical arm, an opening is provided in the housing portion, and the power source is assembled through the opening. In order to avoid the power source from being exposed after assembly, a cover is mounted on the joint portion to close the opening. Patent document 1 discloses a robot arm in which a cover is attached to a joint portion by screw fixation.

The cover is not expected to be removed except for maintenance of the power source, etc. However, when the cover is attached to the joint portion by simple screw locking, the cover may be unnecessarily removed by a user. It is conceivable to take measures for fixing the cover to the joint portion or for attaching a seal sticker by using a special screw which is difficult to be attached and detached by a common tool, but these cannot be said to be perfect measures.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open publication No. 2019-63940

Disclosure of Invention

The invention aims to provide an articulated robot capable of inhibiting unnecessary removal of a cover body mounted on an articulated part of a mechanical arm.

An articulated robot according to an aspect of the present invention includes: a robot arm having a plurality of arm members and a joint portion rotatably connecting the plurality of arm members; a housing portion provided inside the joint portion, having an opening in a side surface of the joint portion, and housing a motor as a driving source of the robot arm; and a cover body closing the opening of the accommodating portion. The cover has an engaging portion, the housing portion has an engaged portion, and the cover is attached to the housing portion so as to close the opening based on the engaging portion being engaged with the engaged portion. The engaging portion has an engaging claw which engages by being fitted into the engaged portion, but which cannot be disengaged from the engaged portion.

Drawings

Fig. 1 is a perspective view of an articulated robot according to an embodiment of the present invention.

Fig. 2 (a) is a front view of one joint portion of the vertical multi-joint 7-axis robot, and fig. 2 (B) is an exploded view with a cover removed from the joint portion.

Fig. 3 is a cross-sectional view of the joint.

Fig. 4 is an exploded perspective view of one joint and a cover.

Fig. 5 (a) is a top view of the cover, fig. 5 (B) is a perspective view of the cover, and fig. 5 (C) is an enlarged perspective view of the vicinity of the engagement claw of the cover.

Fig. 6 is a cross-sectional view of the fitting portion of the cover to which the seal structure is added.

Fig. 7 is an enlarged cross-sectional view of the location of the engaged portion.

Fig. 8 (a) to (E) are side views showing various embodiments of the engagement claw of the cover.

Fig. 9 (a) is a top view of a cover according to a modification, and fig. 9 (B) is a perspective view thereof.

Fig. 10 (a) is a plan view of a cover according to another modification, and fig. 10 (B) is a perspective view thereof.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The articulated robot according to the present invention includes a robot arm having at least 2 arm members and an articulated portion rotatably connecting the arm members. The concept of the arm member is to include a body portion which rotates about a vertical axis with respect to a base, a wrist unit at a distal end of a robot arm, and the like, in addition to a usual arm portion. The joint is a joint that allows one arm member to rotate in a swinging manner with respect to the other arm member. The joint is typically a joint connecting the proximal end of the downstream arm to the distal end of the upstream arm, and is used to swing the downstream arm up and down. In the present embodiment, a multi-joint robot including a plurality of arm members and a plurality of joints is exemplified.

[ Integral robot Structure ]

Fig. 1 is a perspective view of an articulated robot 1 according to an embodiment. Here, a vertical multi-joint 7-axis robot is exemplified as the multi-joint robot 1. The articulated robot 1 includes a robot arm 10 having 7 rotation axes, i.e., a 1 st axis 2A, a 2 nd axis 2B, a 3 rd axis 2C, a 4 th axis 2D, a 5 th axis 2E, a 6 th axis 2F, and a 7 th axis 2G. The robot arm 10 includes a base 11, a body 12 (arm 1 member), an arm 1 (arm 2 member), an arm 2 (arm 3 member), an arm 3 (arm 15), and a head 16.

The base 11 is a frame fixed to the ground, a base, or the like. The body 12 is connected to the upper side surface of the base 11 via a1 st rotation joint 21. The body 12 is rotatable in both forward and reverse directions about the axial center of the 1 st shaft 2A extending in the plumb direction based on the 1 st rotation joint portion 21. The 1 st arm 13 has a predetermined length, and its base end portion is connected to the body portion 12 via the 1 st swing joint portion 22 (1 st joint portion). The 1 st arm 13 is swingable around the axial center of the 2 nd shaft 2B extending in the horizontal direction based on the 1 st swing joint 22. The 1 st arm 13 includes a2 nd revolute joint portion 23 at its center. The distal end side member of the 1 st arm 13 is rotatable about the axial center of the 3 rd shaft 2C extending in the arm shaft direction based on the 2 nd rotational joint portion 23.

The 2 nd arm 14 is an arm connected downstream of the 1 st arm 13, and its base end portion is connected to the distal end portion of the 1 st arm 13 via a2 nd swing joint portion 24 (2 nd joint portion). The 2 nd arm 14 is swingable around the axial center of the 4 th shaft 2D extending in the horizontal direction based on the 2 nd swing joint 24. The 2 nd arm 14 includes a3 rd revolute joint portion 25 at its center. The distal end side member of the 2 nd arm 14 is rotatable about the axial center of the 5 th shaft 2E extending in the arm shaft direction based on the 3 rd rotational joint portion 25.

The 3 rd arm 15 is an arm connected downstream of the 2 nd arm 14, and its base end portion is connected to the distal end portion of the 2 nd arm 14 via the 3 rd swing joint portion 26. The 3 rd arm 15 is swingable around the axial center of the 6 th shaft 2F extending in the horizontal direction based on the 3 rd swing joint portion 26. The head 16 is rotatably mounted on the distal end side of the 3 rd arm 15 about the axial center of the 7 th shaft 2G extending in the vertical direction.

The cover 3 is attached to the side surfaces of the 3 joint parts that swing the arm member, that is, the 1 st, 2 nd, and 3 rd swing joint parts 22, 24, and 26, respectively. Specifically, the 1 st lid 3A is attached to both side surfaces of the 1 st swing joint portion 22 having a substantially cylindrical case shape, and the 2 nd lid 3B is attached to both side surfaces of the 2 nd swing joint portion 24. A 3 rd lid 3C is attached to one side surface of the 3 rd swing joint portion 26. In this embodiment, a scheme satisfying the following functions is adopted: at least one of the covers 3A, 3B, 3C can be attached to each joint without tools, and cannot be detached while maintaining the original shape.

[ Detailed Structure of Joint ]

Fig. 2 (a) is a front view of the 1 st swing joint 22 shown in fig. 1, and fig. 2 (B) is a view showing a state in which the 1 st lid 3A is removed from the 1 st swing joint 22. Fig. 3 is a sectional view of the 1 st swing joint 22. Fig. 4 is an exploded perspective view of the 1 st swing joint portion 22 and the 1 st cover 3A. Referring to fig. 1 and 4, the 2 nd swing joint 24 and the 2 nd lid 3B, and the 3 rd swing joint 26 and the 3 rd lid 3C also have substantially the same structure as the 1 st swing joint 22 and the 1 st lid 3A. Hereinafter, the 1 st swing joint 22 will be simply referred to as a joint 22, and the 1 st lid 3A will be simply referred to as a lid 3.

The joint 22 is provided with a housing 4 (1 st housing) for housing the drive mechanism of the robot arm 10. The joint 22 is configured such that an upper end portion of the housing of the body 12 and a lower end portion of the housing of the base end side member 131 of the 1 st arm 13 are aligned in the horizontal direction, and has a substantially cylindrical shape as described above. The housing portion 4 is a substantially cylindrical housing space provided inside the substantially cylindrical joint portion 22.

Fig. 3 shows a driving mechanism accommodated in the accommodating portion 4. Here, the motor 51 (motor 1), the speed reducer 52, the brake 53, the torque sensor 54, and the controller board 55 are exemplified as the driving mechanism. The 2 nd swing joint portion 24 and the 3 rd swing joint portion 26 are also provided with the same or similar housing portions 4 (2 nd housing portion and 3 rd housing portion), and drive mechanisms including motors 51 (2 nd motor and 3 rd motor) are housed in the respective housing portions 4. Note that, the description of the housing portion 4 provided in the 2 nd swing joint portion 24 and the 3 rd swing joint portion 26 can be referred to as the housing portion 4 provided in the 1 st swing joint portion 22, and therefore, the description thereof will be omitted.

The motor 51 is a drive source for rotating the 1 st arm 13 about the 2 nd axis 2B, and includes a motor shaft 51S for generating a rotational force. The motor 51 may also have a function of decelerating and stopping the rotational movement of the motor shaft 51S. The speed reducer 52 reduces the rotation speed of the motor shaft 51S at a predetermined reduction ratio, and transmits the reduced rotation speed to the rotation mechanism. The brake 53 has a function of suppressing the rotation of the 1 st arm 13 due to its own weight when the motor 51 is not energized (a holding brake function). The torque sensor 54 detects the torque applied to the 1 st arm 13 by the motor 51. The controller board 55 controls the operation of the motor 51 based on a command from an off-board control device and a detection result of the torque sensor 54.

The housing portion 4 has openings 4H on both side surfaces of the joint portion 22. The opening 4H is an opening for facilitating the assembly work of the motor 51 and the like to the housing portion 4 at the time of manufacturing the robot arm 10 or the work of taking out and re-housing the motor 51 from the housing portion 4 at the time of maintenance and the like. The cover 3 is a member for closing the opening 4H of the housing 4. By mounting the cover 3, the motor 51 with heat, the speed reducer 52 including a gear, the controller board 55 on which electronic components are mounted, and the like are not exposed to the outside.

The cover 3 has engagement claws 31 (engagement portions) extending in the depth direction of the housing portion 4. The depth direction is the direction of arrow F1 in the case of the cover 3 on the left side and the direction of arrow F2 in the case of the cover 3 on the right side shown in fig. 2 (B). The engaging claw 31 is an engaging portion mechanically engaged with the housing portion 4, and in the present embodiment, as shown in fig. 4, is provided protruding at 3 at 120-degree intervals on the annular outer peripheral edge of the lid body 3. The engaged portion 41 is provided on the inner peripheral wall of the housing portion 4 in the vicinity of the opening 4H in correspondence with the arrangement of the engaging claws 31. The cover 3 is attached to the housing 4 so as to close the opening 4H by the engagement of the engagement claw 31 with the engagement portion 41.

[ Details of the cover and the engaged portion ]

Next, the detailed structure of the cover 3 having the engagement claws 31 and the engaged portion 41 will be described. Fig. 5 (a) is a plan view of the cover 3, fig. 5 (B) is a perspective view of the cover 3, and fig. 5 (C) is an enlarged perspective view of the vicinity of the engagement claw 31. The lid 3 includes a lid body 30, a fitting body 302, and an engagement claw 31. The cover 3 includes the engagement claws 31 made of a resin material. On the other hand, the housing of the robot arm 10 that partitions the space of the housing portion 4 includes the engaged portion 41 made of a metal material.

The cover main body 30 has a circular shape in plan view, and has a size to close the opening 4H of the housing portion 4. The cover body 30 has a curved surface shape protruding in a direction opposite to the depth direction F1 of the housing portion 4. The fitting body 302 is a cylindrical portion extending in the depth direction F1 from the vicinity of the peripheral edge 301 of the cover main body 30. As shown in fig. 3, the fitting body 302 of the left cover 3 is fitted into the opening 4H so as to be in contact with the inner wall 121 in the vicinity of the opening 4H of the body 12. The peripheral edge 301 has a slightly larger diameter than the fitting body 302 and is flush with the outer surface of the housing of the body 12.

The following is also envisioned: the articulated robot 1 is not capable of sufficiently preventing foreign matter such as dust from entering the housing 4 from the outside even though the cover 3 is attached. Therefore, it is preferable to provide a sealing structure between the inner wall 121 of the opening 4H and the fitting trunk 302. Fig. 6 is a cross-sectional view of the fitting portion of the lid 3 to which the seal structure is added, and is a cross-sectional view showing the fitting portion corresponding to the vicinity of the upper portion of the lid 3 on the left side in fig. 3. An annular groove 122 extending in the circumferential direction of the opening 4H is provided in the inner wall 121 at a position overlapping the fitting body portion 302 in the fitted state. A sealing material 123 such as an O-ring or a lip seal is accommodated in the annular groove 122. The annular groove 122 and the sealing material 123 may be provided on the fitting body 302 side.

The engagement claw 31 includes an extension portion 32 and a protruding portion 33. The extension 32 is a flat plate-like portion extending parallel to the depth direction F1 from the peripheral edge 301 of the cover main body 30. The root portion 321 of the extension portion 32 is connected to the peripheral portion 301. The protruding portion 33 is provided at the distal end portion 322 of the extension portion 32, and protrudes radially outward from the distal end portion 322 of the cap body 30. The protruding portion 33 of the present embodiment has a substantially right triangle shape in side view. Slits 303 are provided on both side portions of the engaging claw 31, and are formed by cutting away portions of the fitting trunk 302. The other two engagement claws 31 are not shown in the drawings, but they are similar. The slit 303 is provided so that the engaging claw 31 has a length in the depth direction F1 that can exhibit a required elastic deformation amount.

The extension 32 has a1 st contact surface 34 extending in the depth direction F1 from the peripheral edge 301 of the cover main body 30. The 1 st contact surface 34 is a plane on the radially outer side of the cover body 30 in the flat extension 32. The protruding portion 33 has a2 nd contact surface 35 protruding from a side of the 1 st contact surface 34 radially outward, and a tapered surface 331 extending obliquely rearward from the distal end portion 322. The 2 nd contact surface 35 is a surface directed to the opposite side of the protrusion 33 from the depth direction F1, and is a surface that exhibits an engagement effect with respect to the engaged portion 41. The tapered surface 331 is a surface for facilitating the engagement of the engagement claw 31 with the engaged portion 41.

Fig. 7 is an enlarged cross-sectional view of the location of the engaged portion 41 in fig. 3. Fig. 7 shows a state in which the cover 3 is fitted into the opening 4H and the engagement claw 31 is engaged with the engaged portion 41. The engaged portion 41 is a small projection extending in the depth direction F1 from an opening edge 124 of the opening 4H of the housing portion 4 in the case of the body portion 12. The engaged portion 41 includes a 1 st receiving surface 42 that makes surface contact with the 1 st contact surface 34 of the engaging claw 31 and a2 nd receiving surface 43 that makes surface contact with the 2 nd contact surface 35. The 1 st receiving surface 42 is a plane directed toward the radial center of the engaged portion 41, and the 2 nd receiving surface 43 is a plane directed toward the depth direction F1.

The engagement claw 31 is a claw that engages by fitting into the engaged portion 41 as shown in fig. 7, but cannot disengage from the engaged portion 41. The phrase "not to disengage from the engagement" means that the engagement of the engaged portion 41 by the engagement claw 31 is substantially impossible to disengage without deforming or breaking the engagement claw 31. When the cover 3 is fitted into the opening 4H, the engaging claw 31 is elastically deformed radially inward with respect to the base end 321 by the guide tapered surface 331 of the introduction portion of the 1 st receiving surface 42. The engaging claw 31 moves in the depth direction F1 when the protruding portion 33 slides against the 1 st receiving surface 42.

After passing the distal end of the 1 st receiving surface 42, the elastic deformation is released, and the 2 nd abutment surface 35 is fitted into the 2 nd receiving surface 43. Thereby, the engagement claw 31 is engaged with the engaged portion 41, and the lid 3 is mounted on the opening 4H. The length of the extended portion 32 of the engagement claw 31 in the depth direction F1 is set to a length that allows the elastic deformation of the protruding portion 33 when sliding against the 1 st receiving surface 42.

On the other hand, a mechanism for disengaging the engagement from the engaged portion 41 is not applied to the engagement claw 31. In the conventional snap fitting, a spring mechanism for releasing the engagement of the engagement claw and the like engaged with the engaged portion is provided. In contrast, the engagement claw 31 is formed to extend from the peripheral edge 301 of the cover main body 30 simply in the depth direction F1, and is not provided with a design or a mechanism for removing the protruding portion 33 temporarily engaged with the engaged portion 41 from the engaged portion 41. Therefore, when the lid 3 is forcibly removed from the opening 4H, if a force equal to or greater than a predetermined force is applied to the lid 3 on the opposite side in the depth direction F1, the engagement claws 31 are plastically deformed or broken. Mainly the root end 321 where stress is easily concentrated is easily damaged.

When the cover 3 is fitted into the opening 4H, the 3 engagement claws 31 are guided by the tapered surfaces 331 and elastically deformed substantially uniformly radially inward. Therefore, after the 3 engagement claws 31 travel a predetermined length in the depth direction F1, they can be engaged with the engaged portions 41, respectively. On the other hand, when the cover 3 is removed from the opening 4H, it is substantially impossible to elastically deform the 3 engagement claws 31 substantially uniformly radially inward as described above. Therefore, only one engagement claw 31 is greatly deformed in order to achieve the removal. If a deformation force exceeding the elastically deformable region is applied to one engagement claw 31, the engagement claw 31 is broken, so that the lid 3 cannot function as a lid for closing the opening 4H. This has the suppressing effect of making the user hesitate to detach the cover 3 unnecessarily.

[ Various embodiments of engagement claw ]

Next, various embodiments of the engagement claw 31 will be described with reference to fig. 8 (a) to (E). Fig. 8 (a) is an enlarged view of the engagement claw 31 and the engaged portion 41 according to embodiment 1, which have been illustrated in fig. 2 to 5 and 7. The angle θ1 between the 1 st contact surface 34 and the 2 nd contact surface 35 of the extension 32 of the engagement claw 31 is 90 degrees. According to the engaging claw 31, the angle formed by the 1 st receiving surface 42 and the 2 nd receiving surface 43 of the engaged portion 41 is also 90 degrees. In a state where the engagement claw 31 is engaged with the engaged portion 41, the 1 st contact surface 34 is in surface contact with the 1 st receiving surface 42, and the 2 nd contact surface 35 is in surface contact with the 2 nd receiving surface 43.

In the engaging portion where the engaging claw 31 having θ1=90 degrees (or 90 degrees or less) engages with the engaged portion 41, the engagement between the 2 nd contact surface 35 and the 2 nd receiving surface 43 cannot be easily released. Therefore, if an external force is applied to remove the cover 3, the engagement claw 31 is easily broken. That is, the engaging claw 3 of the present embodiment does not include a spring mechanism that releases the engagement between the 2 nd contact surface 35 and the 2 nd receiving surface 43 by being retracted upward relative to each other as in the case of the snap fit. Therefore, when the engagement of the two is released, only an external force is applied to break the root end 321 of the engagement claw 31 or to cause the protruding portion 33 to fall off, thereby damaging the original shape of the engagement claw 31. As described above, according to the engagement claw 31 shown in fig. 8 (a), the engagement claw 31 which cannot be disengaged can be realized by a simple claw shape.

Fig. 8 (B) is a diagram showing the engaging claw 31A and the engaged portion 41A according to embodiment 2. The engagement claw 31A includes an extension portion 32A and a protruding portion 33A as in embodiment 1, the extension portion 32A having a1 st contact surface 34A, and the protruding portion 33A having a2 nd contact surface 35A. The difference from embodiment 1 is that the protruding portion 33A has a shape of a so-called "barb". The angle θ2 between the 1 st abutment surface 34A and the 2 nd abutment surface 35A is smaller than 90 degrees due to the shape of the "barb". Here, an example in which θ2=60 degrees is shown.

The engaged portion 41A also has a pointed shape in order to be tightly engaged with the engagement claw 31A. That is, the angle between the 1 st receiving surface 42A and the 2 nd receiving surface 43A of the engaged portion 41A is also set to about 60 degrees. In a state where the engagement claw 31A is engaged with the engaged portion 41A, the 1 st contact surface 34A is in surface contact with the 1 st receiving surface 42A, and the 2 nd contact surface 35A is in surface contact with the 2 nd receiving surface 43A. According to the engaging claw 31A of embodiment 2, since θ2 is set to be smaller than 90 degrees, it is possible to realize the engaging claw 31A which is more difficult to disengage from the engaged portion 41A.

Fig. 8 (C) is a diagram showing the engaging claw 31B and the engaged portion 41B according to embodiment 3. The engagement claw 31B includes an extension portion 32B and a protruding portion 33B similar to embodiment 1, the extension portion 32B having a 1 st contact surface 34B, and the protruding portion 33B having a 2 nd contact surface 35B. The embodiment 1 is similar to the embodiment 1 in that the angle between the 1 st contact surface 34B and the 2 nd contact surface 35B is 90 degrees. According to the engaging claw 31B, the angle formed by the 1 st receiving surface 42B and the 2 nd receiving surface 43B of the engaged portion 41B is also 90 degrees.

The difference from embodiment 1 is that the 2 nd abutment surface 35B has a convex portion 36 having a partial protrusion of its surface and the 2 nd receiving surface 43B has a concave portion 44 having a partial depression of its surface. The convex portion 36 and the concave portion 44 have shapes that can be fitted to each other in a state where the cover 3 is attached to the housing portion 4, that is, in a state where the engagement claw 31B is engaged with the engaged portion 41B. The convex portion 36 and the concave portion 44 may be tightly fitted, or may be fitted with a predetermined play. According to embodiment 3, the protrusion 36 fits in the recess 44, so that the relative sliding movement between the 2 nd contact surface 35B and the 2 nd receiving surface 43B is restricted. Therefore, the locking portion that cannot be disengaged can be easily realized.

Fig. 8 (D) is a diagram showing the engagement claw 31C and the engaged portion 41C according to embodiment 4. Embodiment 4 is a modification of embodiment 3, and is an example in which the fitting of the irregularities is reversed. The engagement claw 31C includes an extension portion 32C and a protruding portion 33C, the extension portion 32C having a 1 st contact surface 34C, and the protruding portion 33C having a 2 nd contact surface 35C. The engaged portion 41C includes a 1 st receiving surface 42C and a 2 nd receiving surface 43C in accordance with the engaging claw 31C.

The 2 nd contact surface 35C has a recess 37 partially recessed in the surface thereof, and the 2 nd receiving surface 43C has a projection 45 partially protruding in the surface thereof. The concave portion 37 and the convex portion 45 have shapes that can be fitted to each other in a state where the cover 3 is attached to the housing portion 4, that is, in a state where the engagement claw 31C is engaged with the engaged portion 41C. According to embodiment 4, the protrusion 45 is fitted in the recess 37, so that the relative sliding movement between the 2 nd contact surface 35C and the 2 nd receiving surface 43C can be restricted.

Fig. 8 (E) is a diagram showing the engaging claw 31D and the engaged portion 41D according to embodiment 5. The engaging claw 31D includes an extension portion 32D and two protruding portions, that is, a 1 st protruding portion 33D1 and a2 nd protruding portion 33D2. The 1 st protruding portion 33D1 and the 2 nd protruding portion 33D2 are provided protruding from the extension portion 32D so as to be aligned in the depth direction F1 of the housing portion 4. The extension portion 32D has a 1 st contact surface 34D, and the 1 st projection 33D1 and the 2 nd projection 33D2 have 2 nd contact surfaces 35D1, 35D2, respectively. The engaged portion 41D includes a 1 st receiving surface 42D and two 2 nd receiving surfaces 43D1, 43D2 according to the engaging claw 31D.

In a state where the engagement claw 31D is engaged with the engaged portion 41D, the 2 nd contact surface 35D1 of the 1 st protruding portion 33D1 on the front side is engaged with the 2 nd receiving surface 43D1 which is the distal end surface of the engaged portion 41D, and the 2 nd contact surface 35D2 of the 2 nd protruding portion 33D2 on the rear side is engaged with the 2 nd receiving surface 43D2 on the rear side. The rear 2 nd receiving surface 43D2 is a receiving surface generated by forming a groove 46 capable of accommodating the 2 nd protruding portion 33D2 in a part of the 1 st receiving surface 42D. According to embodiment 5, the 1 st protruding portion 33D1 and the 2 nd protruding portion 33D2 arranged in the depth direction F1 are engaged with the engaged portion 41D, respectively. Therefore, in order to remove the cover 3, it is necessary to release the engagement between the 1 st and 2 nd protruding portions 33D1, 33D2, and the engagement-disabled locking claw can be easily realized.

According to the articulated robot according to the present embodiment described above, the driving mechanism of the robot arm 10 including the motor 51 is accommodated in the accommodation portion 4 having the opening 4H provided in the swing joint portions 22, 24, 26. Therefore, the operator can easily assemble the motor 51 to the housing portion 4 or maintain the motor 51 at the time of manufacturing the robot arm 10 through the opening 4H.

Further, the lid 3 closing the opening 4H can be engaged by the engagement claw 31 being fitted into the engaged portion 41, and therefore can be easily attached to the housing portion 4 without a tool. On the other hand, the engagement claw 31 cannot be disengaged from the engaged portion 41 after being engaged with the engaged portion 41. Therefore, only the engaging claw 31 is broken in order to remove the cover 3 from the housing portion 4. That is, the action of exposing the opening 4H in order to remove the cover 3 is accompanied by breakage of the engaging claw 31. Since the cover 3 is substantially disabled due to breakage of the engagement claws 31, the user can hesitate to detach the cover 3 unnecessarily.

Modified embodiment

The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments, and can be modified as follows.

(1) As described above, no mechanism is provided to positively release the engagement of the engaged portion 41 by the engagement claw 31 as in the snap fit. Therefore, in order to remove the lid body 3, an operator having a proper authority such as a maintenance worker must perform a work of inserting a detaching tool into a gap between the peripheral edge 301 of the lid body 30 and the edge of the opening 4H and prying the lid body 3. In this operation, it is preferable that the detaching tool is inserted in the vicinity of the engaging claw 31 and an external force is applied to the lid body 3 by the principle of a lever, but the position of the engaging claw 31 cannot be recognized from the outside.

Fig. 9 (a) is a plan view of the cover 3D according to the modification, and fig. 9 (B) is a perspective view thereof. The cover 3D has a mark 38 indicating the position of use of the cover 3D in a state where the detaching tool is attached to the housing 4. The mark portion 38 is a small projection protruding from a surface of the cover main body 30 near the peripheral edge 301 of the cover main body 30 near the position where the one engagement claw 31 is disposed. The operator can insert a removal tool such as a straight screwdriver with reference to the position of the mark portion 38. The logo 38 may be a pit, printed text or indicia, or the like. Further, since the engagement claws 31 are damaged when the cover 3 is removed, an operator installs a new cover 3 in the opening 4H after performing maintenance.

Fig. 10 (a) is a plan view of a lid 3E according to another modification, and fig. 10 (B) is a perspective view thereof. As a place of the above-described marker portion 38, the cover 3E is provided with a cutout portion 39 into which the distal end portion of the in-line screwdriver can be inserted. The notch 39 is a portion cut out by partially conforming the peripheral edge 301 to the distal end shape of the in-line screwdriver in the vicinity of the arrangement position of one engagement claw 31. The cutout 39 may be provided on the housing side of the housing 4. According to these modifications, the cover 3 of a maintenance worker or the like can be removed with good workability.

(2) The engaging claw 31 of the cover 3 may have a pressing function for pressing the start button of the articulated robot 1 or the arm 10. For example, an actuation button pressed by the distal end portion 322 of the engagement claw 31 is arranged in advance on the inner wall of the housing portion 4. Of course, if the engaging claw 31 is deformed or separated, the start button is not pressed, and the articulated robot 1 does not operate. For example, when the user who does not have the right to detach the cover 3 removes the cover 3, the articulated robot 1 cannot operate, and thus an effect of suppressing unnecessary detachment of the cover 3 can be expected.

(3) In the above embodiment, an example in which the cover 3 includes the engaging claw 31 made of a resin material and the housing of the mechanical arm 10 includes the engaged portion 41 made of a metal material is shown. Instead of this, both the engaging claw 31 and the engaged portion 41 may be made of a resin material or a metal material. However, as in the above embodiment, if the engaging claw 31 is made of a resin material having a relatively low strength and the engaged portion 41 is made of a metal material having a relatively high strength, the deformation or detachment of the engaging claw 31 can be easily caused when a force for removing the lid 3 is applied based on the difference in strength between the two.

[ Invention included in the above embodiment ]

An articulated robot according to an aspect of the present invention includes: a robot arm having a plurality of arm members and a joint portion rotatably connecting the plurality of arm members; a housing portion provided inside the joint portion, having an opening in a side surface of the joint portion, and housing a motor as a driving source of the robot arm; and a cover body closing the opening of the accommodating portion; the cover body is provided with an engaging portion, the accommodating portion is provided with an engaged portion, the cover body is mounted on the accommodating portion in a manner of closing the opening based on the engaging portion being engaged with the engaged portion, and the engaging portion is provided with an engaging claw which engages with the engaged portion by being embedded therein and cannot be disengaged from the engaged portion.

According to the robot described above, since the motor is accommodated in the accommodating portion having the opening, the assembly of the motor to the accommodating portion and the maintenance of the motor at the time of manufacturing the robot arm can be easily performed through the opening. Further, the lid body closing the opening can be engaged by the engagement claw being fitted into the engaged portion, and therefore can be easily attached to the housing portion without a tool. On the other hand, after the engaged portion of the housing portion is engaged, the engagement claw cannot be disengaged from the engaged portion. Therefore, only the engaging claw is broken in order to remove the cover from the housing portion. Such breakage causes the cover to substantially lose function, and thus can make the user hesitate to detach the cover unnecessarily.

In the above-described articulated robot, it may be that: the robot arm is a multi-joint robot arm including a1 st joint portion connecting a1 st arm member and a 2 nd joint portion connecting a 2 nd arm member and a 3 rd arm member, and includes, as the housing portions, a1 st housing portion housing a1 st motor inside the 1 st joint portion and a 2 nd housing portion housing a 2 nd motor inside the 2 nd joint portion, and the cover having the engagement claw is attached to at least one of the 1 st housing portion and the 2 nd housing portion.

According to this robot, the cover having the above-described advantages can be used for the joint portion of the multi-joint mechanical arm having 3 or more arm members and 2 or more joint portions.

In the above-described articulated robot, it is preferable that: the engagement claw includes an extension portion having a 1 st contact surface extending in a depth direction of the housing portion from a peripheral edge portion of the cover body, and a protruding portion having a 2 nd contact surface protruding laterally from the 1 st contact surface, and the engaged portion includes a 1 st receiving surface with which the 1 st contact surface is brought into contact and a 2 nd receiving surface with which the 2 nd contact surface is brought into contact, and an angle formed by the 1 st contact surface and the 2 nd contact surface is 90 degrees or less.

According to this robot, the engaging claw protrudes from the peripheral edge of the cover in the depth direction of the housing portion. The cover is engaged with the housing portion by an engaging claw having an angle of 90 degrees or less formed by the 1 st contact surface and the 2 nd contact surface, and an engaged portion having the 1 st receiving surface and the 2 nd receiving surface with which the contact surfaces are brought into contact. In such an engagement mode, if an external force is applied to release the surface contact state in order to remove the cover, breakage is likely to occur at the root end portion of the engagement claw. Therefore, the engagement claw which cannot be disengaged can be realized by the simple claw shape.

In the above-described articulated robot, the following configuration may be adopted: the engaging claw includes a1 st protruding portion and a 2 nd protruding portion arranged in a depth direction of the accommodating portion as the protruding portion, and the engaged portion includes two 2 nd receiving surfaces that are brought into surface contact with 2 nd contact surfaces of the 1 st protruding portion and the 2 nd protruding portion.

According to this robot, the 1st protruding portion and the 2 nd protruding portion arranged in the depth direction of the housing portion are engaged with the engaged portions, respectively. Therefore, in order to remove the cover, the engagement between the 1st and 2 nd protruding portions must be released, and the engagement-disabled locking claw can be easily realized.

In the above-described articulated robot, it may be that: the 2 nd contact surface has a convex portion partially protruding from a surface thereof, the 2 nd receiving surface has a concave portion partially recessed from a surface thereof, and the convex portion has a shape capable of fitting into the concave portion in a state in which the cover is attached to the housing portion. Or may be: the 2 nd contact surface has a partially recessed recess on a surface thereof, and the 2 nd receiving surface has a partially protruding protrusion on a surface thereof, and the recess has a shape capable of receiving the protrusion in a state in which the cover is mounted to the housing portion.

According to this robot, the relative sliding movement between the 2 nd contact surface and the 2 nd receiving surface is restricted by the fitting of the concave portion and the convex portion. Therefore, the locking claw which cannot be disengaged from the engagement can be easily realized.

In the above-described articulated robot, it is preferable that: the engaging portion is made of a resin material, and the engaged portion is made of a metal material.

According to the robot, the engaging portion is made of a resin material having relatively low strength, and the engaged portion is made of a metal material having relatively high strength. The difference in strength makes it more difficult to remove the cover body with the engagement claws maintained.

In the above-described articulated robot, it is preferable that: the cover has a mark portion indicating a use position of the cover removing tool in a state of being attached to the housing portion. The marking part may be a cut-out part into which a distal end part of the straight screwdriver can be inserted.

According to this robot, the workability of a person who has the right to remove the cover, such as a maintenance worker, can be improved.

Claims (9)

1. An articulated robot, comprising:

a robot arm having a plurality of arm members and a joint portion rotatably connecting the plurality of arm members;

a housing portion provided inside the joint portion, having an opening in a side surface of the joint portion, and housing a motor as a driving source of the robot arm; and

A cover body closing the opening of the accommodating portion; wherein,

The cover body has an engaging portion, the housing portion has an engaged portion, the cover body is mounted to the housing portion so as to close the opening based on the engaging portion being engaged with the engaged portion,

The engaging portion has an engaging claw which engages by being fitted into the engaged portion, but which cannot be disengaged from the engaged portion.

2. The articulated robot of claim 1, wherein the articulated robot comprises,

The robot arm is a multi-joint robot arm including a1 st joint portion connecting a1 st arm member and a2 nd joint portion connecting the 2 nd arm member and a 3 rd arm member,

The housing part includes a1 st housing part for housing the 1 st motor in the 1 st joint part and a2 nd housing part for housing the 2 nd motor in the 2 nd joint part,

The cover having the engaging claw is attached to at least one of the 1 st housing portion and the 2 nd housing portion.

3. The articulated robot according to claim 1 or 2, wherein,

The engagement claw includes an extension portion having a 1 st contact surface extending in a depth direction of the housing portion from a peripheral edge portion of the cover body, and a protruding portion having a2 nd contact surface protruding laterally from the 1 st contact surface,

The engaged portion includes a1 st receiving surface that makes the 1 st contact surface contact and a 2 nd receiving surface that makes the 2 nd contact surface contact,

The angle formed by the 1 st contact surface and the 2nd contact surface is less than 90 degrees.

4. The articulated robot of claim 3, wherein,

The engaging claw includes a1 st protruding portion and a2 nd protruding portion arranged in a depth direction of the receiving portion as the protruding portion,

The engaged portion includes two 2 nd receiving surfaces that are in surface contact with the 2 nd contact surfaces of the 1 st projecting portion and the 2 nd projecting portion.

5. The articulated robot of claim 3 or 4, wherein,

The 2 nd abutment surface has a locally protruding boss of its surface,

The 2 nd bearing surface has a partially concave recess of its surface,

The protruding portion has a shape capable of fitting with the recessed portion in a state where the cover is attached to the housing portion.

6. The articulated robot of claim 3 or 4, wherein,

The 2 nd abutment surface has a partially concave recess of its surface,

The 2 nd bearing surface has a convex part of its surface which partially protrudes,

The concave portion has a shape capable of receiving the convex portion in a state where the cover is attached to the housing portion.

7. The articulated robot according to any one of claim 1 to 6, wherein,

The engaging portion is made of a resin material, and the engaged portion is made of a metal material.

8. The articulated robot of any of claims 1 to 7,

The cover has a mark portion indicating a use position of the cover removing tool in a state of being attached to the housing portion.

9. The articulated robot of claim 8, wherein the articulated robot comprises,

The mark part is a notch part into which the distal end part of the straight screwdriver can be inserted.