HOLDER, ROBOT, WELDING DEVICE AND ROBOT SYSTEM

Abstract

The present invention provides a holder comprising: a holder body (4) attached to a tool mounting surface (2a) of an arm member, with an insulating plate (9) arranged between them; insulating elements, which are holder fastening devices that secure the holder body (4) to the tool mounting surface (2a) from the inside and electrically insulate the holder body (4) from each other; and an insulating cover (10) having electrical insulating properties and arranged in the holder body (4). The holder body (4), the insulating plate (9), and the insulating cover (10) each have a hollow bore (41a, 9a, 10c) through which a supply element (A) is guided from the inside of the arm member into the interior of the holder body (4). The holder fastening devices include bolts (5) that are attached to threaded bores (2c) in the tool mounting surface (2a).The insulating cover (10) covers a gap between the hollow bore (41a) of the holder body (4) and the supply element (A) and is fastened to the holder body (4) by the bolts (5).

Description

{Technical field}

[0001] The present invention relates to a holder, a robot, a welding device and a robot system. {State of the art}

[0002] An industrial robot for applications such as welding is provided with an insulating structure that electrically insulates a tool and a robot body to prevent current from flowing from the tool into the robot body (see, for example, Patent Documents 1 to 3). In the case of Patent Document 1, an insulating member is interposed between a robot body and a tool. In the cases of Patent Documents 2 and 3, a disc-shaped insulating member is interposed between a reduction gear at a distal end portion of a robot body and a flange of the wrist, and insulating washers and insulating collars are interposed between the wrist flange and bolts that fix the wrist flange to the robot body.

[0003] Meanwhile, there are cases where a holder with a hollow structure is used to attach a tool to a tool attachment surface of a hollow arm member (see, for example, Patent Literatures 4 and 5). An opening is provided in the tool attachment surface of the hollow arm member to allow the supply member to be pulled out from the inside of the arm member. If a tool without a hollow body is directly attached to the tool attachment surface, the opening is closed by the tool, and the supply member cannot be pulled out. By using a holder with a hollow structure, the tool that does not have a hollow structure can be attached to the tool attachment surface.In particular, the tool, which does not have a hollow structure, is attached to the tool attachment surface separated therefrom by the holder, and the supply element is guided from the opening to the tool via the interior of the holder. {Reference list}{Patent specifications} {PTL 1] The Japanese Patent Application Laid-Open, Publication No. Sho 62-142083 {PTL 2] Japanese Laid-Open Patent Application Publication No. 2013-202697 {PTL 3] Japanese Laid-Open Patent Application, Publication No. Hei 11-114873 {PTL 4] Publication of Japanese Patent No. 5344315 {PTL 5] Japanese Laid-Open Patent Application, Publication No. Hei 08-047886 {Explanation of the invention}{Technical problem}

[0004] The holder is provided with a hollow hole that communicates with a hollow portion of the arm link and through which the supply element passes inside the holder. The hollow portion of the arm link is exposed to the interior of the holder via the hollow hole of the holder. In addition, there are cases where metallic components that attach the holder to the robot body, such as bolts, are arranged inside the holder.

[0005] The interior of the holder is open to the outside of the holder, allowing the supply element to be drawn out from inside the holder. Therefore, it is necessary to prevent the electrical insulation properties between the holder and the robot body from deteriorating when foreign matter with lower electrical insulation properties than air, such as splashes, enters the holder from the outside and adheres to components inside the holder and the hollow section of the arm link. {Solution to the task}

[0006] One aspect of the present disclosure is a holder comprising: a holder body having a hollow structure and being fixed to a tool mounting surface of a hollow arm member, with an insulating plate having electrical insulating properties interposed therebetween; insulating members that electrically insulate the holder fixing means that fix the holder body to the tool mounting surface from the inside of the holder body, and the holder body from each other; and an insulating cover having electrical insulating properties that is disposed in the holder body; wherein the holder body, the insulating plate, and the insulating cover each have a hollow bore through which a supply element is passed from the inside of the arm member into the interior of the holder body via an opening of the tool mounting surface;the holder fastening means comprise one or more bolts which are fastened to the threaded holes provided in the tool fastening surface by passing through the through holes in the holder body, the insulating plate and the insulating cover, and the insulating cover covers a gap between the hollow bore of the holder body and the supply element and is fastened to the holder body by fastening the bolts; {Brief description of the drawings} { Fig. 1] Fig. 1 is a diagram illustrating the overall configuration of a robot according to an embodiment of the present disclosure. { Fig. 2] Fig. 2 is a side view of a holder according to the embodiment of the present disclosure attached to a tool mounting surface of a robot body. { Fig. 3] Fig. 3 is a longitudinal cross-sectional view showing a bracket body of the bracket of Fig. 2 illustrates. { Fig. 4] Fig. 4 is a side cross-sectional view of the bracket along line II in Fig. 2. { Fig. 5] Fig. Figure 5 is a partial cross-sectional view of the bracket in the longitudinal direction along the line II-II in Fig. 4. { Fig. 6] Fig. 6 is a partial longitudinal cross-sectional view illustrating a modification of the bracket. { Fig. 7] Fig. Figure 7 is a partial longitudinal cross-sectional view illustrating a further modification of the bracket. { Fig. 8] Fig. Figure 8 is a partial longitudinal cross-sectional view illustrating another modification of the bracket. { Fig. 9] Fig. Figure 9 is a partial longitudinal cross-sectional view illustrating another modification of the bracket. { Fig. 10] Fig. Figure 10 is a partial longitudinal cross-sectional view illustrating another modification of the bracket. { Fig. 11] Fig. Figure 11 is a partial longitudinal cross-sectional view illustrating another modification of the bracket. { Fig. 12] Fig. Figure 12 is a partial longitudinal cross-sectional view illustrating another modification of the bracket. { Fig. 13] Fig. Figure 13 is a partial longitudinal cross-sectional view illustrating another modification of the bracket. { Fig. 14] Fig. 14 is a front view of a in the holder of Fig. 13 provided terminal. {Description of the embodiment}

[0007] A holder 1, a robot 20, a welding apparatus, and a robot system according to an embodiment of the present disclosure will be described below with reference to the drawings.

[0008] As in Fig. 1, the robot 20 is an industrial robot including a robot body 2 and the holder 1 having a hollow structure and adapted to be attached to a tool attachment surface 2a of the robot body 2.

[0009] The robot body 2 has at least one arm member. A distal end surface of an arm member 2b at the distal end of the robot body 2 serves as a tool mounting surface 2a to which a tool 3 or the holder 1 is mounted. The tool mounting surface 2a is provided with a plurality of threaded holes 2c (see Fig. 5) for bolts (holder fastening devices) 5 which fasten the tool 3 or the holder 1 to the tool fastening surface 2a.

[0010] The arm member 2b is hollow at the distal end, and a hollow section 2d (see Fig. 5) The arm link 2b is provided with an opening in the tool mounting surface 2a. For example, in the case where the robot body 2 is a 6-axis vertically articulated robot, the arm link 2b is a cylindrical element that rotates about a sixth axis. A supply element A, which supplies the tool 3 with power and signals, etc., is guided in the hollow section 2d, and the supply element A is pulled outward from the arm link 2b through the opening in the tool mounting surface 2a.

[0011] In the case where a tool 3 that does not have a hollow structure is directly attached to the tool mounting surface 2a, the opening of the hollow portion 2d is closed by the tool 3, and the umbilical A cannot be withdrawn from the hollow portion 2d. Therefore, a tool 3 that does not have a hollow structure cannot be directly attached to the tool mounting surface 2a. The holder 1 enables the attachment of a tool 3 that does not have a hollow structure to the tool mounting surface 2a. The holder 1 can be provided as part of the robot system including the robot 20 and the tool 3.

[0012] As in the Fig. 2 to 5, the holder 1 comprises: a holder body 4 fixed to the tool mounting surface 2a by the holder fixing means; insulating members; an insulating cover 10; and collars 11.

[0013] As in Fig. 3, the holder body 4 is a box-shaped member having a hollow structure and formed of a conductive metal material, and includes a flat, plate-shaped base end wall 41 and a flat, plate-shaped distal end wall 42 arranged parallel to each other with a space therebetween, and a cylindrical side wall 43 connecting the base end wall 41 and the distal end wall 42.

[0014] An outer surface of the base end wall 41 is provided with a robot attachment surface 4a, which is fixed to the tool attachment surface 2a of the arm link 2b, with an insulating plate 9 having electrical insulation properties interposed therebetween. Furthermore, an outer surface of the distal end wall 42, located on the side opposite the tool attachment surface 2a, is provided with a tool attachment surface 4b, to which the tool 3 is attached.

[0015] The base end wall 41 has a hollow bore 41a extending through the base end wall 41 in the thickness direction at a position opposite to the opening of the hollow portion 2d when the holder body 4 is attached to the tool mounting surface 2a of the arm member 2b. Furthermore, the base end wall 41 has a plurality of through holes 41b extending through the base end wall 41 in the thickness direction in a region surrounding the hollow bore 41a.

[0016] The respective through holes 41b are provided at positions corresponding to the threaded holes 2c of the tool mounting surface 2a when the holder body 4 is mounted to the tool mounting surface 2a of the arm member 2b. Each of the through holes 41b is provided with a counterbore 12 having a prescribed depth from an inner surface of the holder body 4.

[0017] The insulating plate 9 has an annular shape and is provided with a hollow hole 9a extending therethrough in the thickness direction at a central position opposite to the opening of the hollow portion 2d when the insulating plate 9 is arranged on the tool attachment surface 2a of the arm member 2b, as shown in Fig. 5. Furthermore, the insulating plate 9 includes, in a region surrounding the hollow bore 9a, a plurality of through holes 9b extending therethrough in the thickness direction. The through holes 9b are provided at positions corresponding to the threaded holes 2c when the insulating plate 9 is arranged on the tool mounting surface 2a of the arm member 2b.

[0018] Accordingly, when the holder body 4 is attached to the tool mounting surface 2a of the arm member 2b with the insulating plate 9 interposed therebetween, an interior of the holder body 4 and the hollow portion 2d of the arm member 2b communicate with each other via the hollow holes 9a and 41a. The supply element A is guided from the opening of the hollow portion 2d through the hollow holes 9a and 41a into the interior of the holder body 4. The insulating plate 9 can be provided as part of the robot body 2 or as part of the holder 1.

[0019] The distal end wall 42 may include a window 42a extending in the thickness direction through the distal end wall 42 and through which the umbilical member A can be passed, and threaded holes 42b for attaching the tool 3. In the case where the tool 3 has a hollow structure, the umbilical member A is connected to the tool 3 via the window 42a, which is attached to the tool attachment surface 4b.

[0020] The side wall 43 has at least one window 43a extending in the thickness direction through the side wall 43 and through which the supply element A can pass. If the tool 3 does not have a hollow structure, the supply element A is pulled outwardly from the holder 1 through the window 43a to be connected to the tool 3.

[0021] The holder fastening devices comprise a plurality of bolts 5 that are fastened to the threaded holes 2c of the tool mounting surface 2a. The holder fastening devices may, as needed, include metal washers 6 that are used together with the corresponding bolts 5. The bolts 5 and the metal washers 6 are formed from a high-strength material, for example, steel.

[0022] The insulating members are formed of a material having electrical insulating properties, e.g., a resin, and each comprise a cylindrical insulating sleeve 7 and an annular, plate-shaped insulating washer 8. The insulating sleeve 7 and the insulating washer 8 comprise internal holes through which the bolt 5 is passed.

[0023] The insulating sleeve 7 covers an outer peripheral surface of the bolt 5, which is arranged between the insulating washer 8 and the insulating plate 9. The insulating washer 8 has, for example, the same outer diameter and inner diameter dimensions as the metal washer 6.

[0024] The collars 11 are formed of a high-strength material, such as steel. The collars 11 each have an inner hole 11c through which the bolt 5 covered with the insulating sleeve 7 passes. They also have a small-diameter portion 11a with a specific outer diameter dimension and a large-diameter flange portion 11b projecting radially outward from the small-diameter portion 11a at one end in the radial direction of the small-diameter portion 11a. The flange portion 11b is formed with an outer diameter dimension equal to or larger than that of the insulating washer 8 and the metal washer 6.

[0025] The small-diameter portion 11a of the collar 11 is inserted into the counterbore 12 provided in the through hole 41b within the base end wall 41 (on the side opposite the tool mounting surface 2a), and a distal end of the small-diameter portion 11a is brought into close contact with a counterbore surface 12a. On one end surface on a flange portion 11b of the collar 11, the insulating washer 8 and the metal washer 6 are stacked in this order in the thickness direction.

[0026] Preferably, the insulating cover 10 is elastically deformable, and the insulating cover 10 is formed, for example, from a sponge. The insulating cover 10 includes an annular, plate-shaped flat portion 10a disposed on the inner side of the base end wall 41, and a cylindrical tubular portion 10b extending vertically from the flat portion 10a at the center of the flat portion 10a and inserted into the hollow bore 41a. A hollow bore 10c is formed in the tubular portion 10b, through which the supply element A extends in the axial direction.

[0027] Preferably, the tube portion 10b closes a cylindrical gap between an inner peripheral surface of the hollow bore 41a and an outer peripheral surface of the supply element A. For example, the tube portion 10b has an inner diameter smaller than an outer diameter of the supply element A and an outer diameter larger than an inner diameter of the hollow bore 41a, and is elastically contractible in the radial direction. In this case, an outer peripheral surface of the tube portion 10b comes into contact with the inner peripheral surface of the hollow bore 41a, and an inner peripheral surface of the tube portion 10b comes into contact with the outer peripheral surface of the supply element A, so that the gap described above is closed.

[0028] In addition, the insulating cover 10 includes a plurality of through holes 13 arranged at positions corresponding to the through holes 41b of the holder body 4 when the pipe section 10b is inserted into the hollow hole 41a from the inside of the holder body 4.

[0029] Each of the through holes 13 of the insulating cover 10 is configured to have a two-stage structure (stepped shape) including: a small-diameter hole 13a into which the small-diameter portion 11a of the collar 11 is inserted; and a large-diameter hole 13b into which the flange portion 11b of the collar 11 is inserted.

[0030] The large-diameter hole 13b of the through-hole 13 has an inner diameter slightly smaller than the outer diameter dimensions of the flange portion 11b of the collar 11 to be attached thereto, the insulating washer 8, and the metal washer 6. In addition, the axial direction length dimension of the small-diameter hole 13a of the insulating cover 10 is set slightly larger than a dimension by subtracting the depth dimension of the counterbore 12 of the holder body 4 from the length dimension of the small-diameter portion 11a of the collar 11. In addition, the axial direction length dimension of the large-diameter hole 13b of the insulating cover 10 is set to be a dimension by adding the thickness dimension of the large-diameter portion 11b of the collar 11, the thickness dimension of the insulating washer 8, and the thickness dimension of the metal washer 6.

[0031] The operation of the holder 1 thus formed and the robot 20 according to this embodiment will be described below.

[0032] To attach the holder 1 according to this embodiment to the robot 20, first, the supply element A extracted from the hollow portion 2d of the arm member 2b of the robot 20 is passed through the hollow hole 9a of the insulating plate 9. Then, the supply element A, which has been passed through the hollow hole 9a of the insulating plate 9, is passed through the hollow hole 41a provided in the base end wall 41 of the holder body 4 and brought into the interior of the holder body 4.

[0033] Furthermore, the insulating cover 10 is inserted into the interior of the holder body 4 from the window 43a of the side wall 43 of the holder body 4, and the supply element A led out into the interior of the holder body 4 is passed through the hollow hole 10c of the inserted insulating cover 10. Subsequently, the tubular portion 10b of the insulating cover 10 is inserted into the hollow hole 41a of the holder body 4. Accordingly, the flat portion 10a of the insulating cover 10 is arranged to cover the inner surface of the base end wall 41 of the holder body 4.

[0034] Furthermore, the tube portion 10b of the insulating cover 10 elastically deforms in the radial direction, the inner peripheral surface of the tube portion 10b comes into close contact with the outer peripheral surface of the supply element A, and the outer peripheral surface of the tube portion 10b comes into close contact with the hollow bore 41a. Accordingly, the gap between the supply element A and the hollow bore 41a of the holder body 4 is sealed by the insulating cover 10.

[0035] Furthermore, the collar 11, the insulating washer 8 and the metal washer 6 are inserted in this order into each of the through holes 13 of the insulating cover 10, the small diameter portion 11a of the collar 11 is inserted into the counterbore 12 provided in the through hole 41b of the holder body 4, and the distal end of the collar 11 abuts against the counterbore surface 12a. When the distal end of the base end wall 41 of the holder body 4 abuts against the counterbore surface 12a, the length dimension from the inner surface of the base end wall 41 of the collar 11 to the flange portion 11b of the collar 11 becomes slightly smaller than the length dimension of the hole 13a of the through hole 13 of the insulating cover 10. Accordingly, the insulating cover 10 is held by the inner surface of the base end wall 41 of the holder body 4 and the flange portion 11b of the collar 11.

[0036] In addition, when the collar 11 is inserted into the through hole 13 of the insulating cover 10, an outer peripheral surface of the flange portion 11b of the collar 11 is in close contact with an inner peripheral surface of the large diameter hole 13b of the through hole 13 due to the elasticity of the insulating cover 10. In addition, when the insulating washer 8 and the metal washer 6 are inserted into the through hole 13, the outer peripheral surfaces of the insulating washer 8 and the metal washer 6 are in close contact with the inner peripheral surface of the large diameter hole 13b of the through hole 13 due to the elasticity of the insulating cover 10.

[0037] In this state, the insulating plate 9 is arranged on the tool mounting surface 2a of the arm member 2b at the position where the hollow hole 9a of the opening of the hollow portion 2d and the through holes 9b face the threaded holes 2c. Subsequently, in a state where the bolts 5 are inserted into the inner holes of the insulating sleeves 7, they are inserted together with the insulating sleeves 7 into the inner holes of the metal discs 6, the insulating washers 8, and the collars 11, as well as into the through holes 41b, and are fixed to the threaded holes 2c provided in the tool mounting surface 2a.

[0038] Accordingly, the axial forces of the bolts 5 are transmitted to the base end wall 41 of the holder body 4 via the metal washers 6, the insulating washers 8 and the collars 11, and the base end wall 41 of the holder body 4 is fixed to the tool mounting surface 2a of the arm member 2b with the insulating plate 9 interposed therebetween.

[0039] The tool mounting surface 2a of the arm member 2b and the robot mounting surface 4a of the holder body 4 are electrically insulated from each other by interposing the insulating plate 9 therebetween.

[0040] Furthermore, because the bolts 5 are secured to the threaded holes 2c provided in the tool mounting surface 2a of the arm member 2b, the bolts 5, the metal discs 6, and the arm member 2b are electrically connected to each other. Furthermore, because the collars 11 are in close contact with the counterbore surfaces 12a of the counterbores 12 provided in the base end wall 41 of the holder body 4, the collars 11 are electrically connected to the holder body 4.

[0041] In contrast, the outer peripheral surfaces of the bolts 5 and the inner surfaces of the inner holes of the collars 11, as well as the outer peripheral surfaces and the inner surfaces of the through holes 41b of the holder body 4, are electrically insulated from each other by the insulating sleeves 7 and the metal washers 6, and the collars 11 are electrically insulated from each other by the insulating washers 8. Therefore, the bolts 5 and the metal washers 6 are electrically insulated from the holder body 4 and the collars 11, and thus the holder body 4 and the robot body 2 are electrically insulated from each other.

[0042] The tool 3 is attached to the tool attachment surface 4b of the holder body 4, which is attached to the tool attachment surface 2a. In the case where the tool 3 has a hollow structure, the umbilical A is drawn from the opening of the hollow portion 2d of the arm member 2b at the distal end into the interior of the holder body 4 and connected to the tool 3 via the window 42a of the distal end wall 42. In the case where the tool 3 does not have a hollow structure, the umbilical A is drawn from the interior of the holder body 4 to the outside of the holder body 4 via the window 43a of the side wall 43 and connected to the tool 3.

[0043] For example, when the tool 3 is used for welding, a current emitted by the tool 3 could flow into the holder body 4. Since the holder body 4 and the robot body 2 are insulated from each other in this embodiment, the current can be prevented from flowing from the holder body 4 into the robot body 2.

[0044] In addition, as in Fig. 4 and Fig. As illustrated in Fig. 5, in the state where the holder body 4 is attached to the tool mounting surface 2a, the inner surface of the base end wall 41 of the holder body 4, which has a hollow structure, is almost completely covered with the insulating cover 10, including the gap between the umbilical A and the hollow bore 41a. Only the heads 5a of the plurality of bolts 5 and the metal washers 6 are exposed without being covered with the insulating cover 10. When the tool 3 is used for welding, foreign matter such as welding spatter generated during welding may also become trapped inside the holder body 4.

[0045] In this case, the surfaces of the collars 11 electrically connected to the holder body 4 are not exposed because they are covered without gaps by the large-diameter holes 13b of the through-holes 13 of the insulating cover 10 and the insulating washers 8. Furthermore, in the embodiment of the holder 1 and the robot 20, the outer peripheral surfaces of the flange portions 11b of the collars 11 and the outer peripheral surfaces of the insulating washers 8 are mounted in close contact with the large-diameter holes 13b of the through-holes 13 of the insulating cover 10. Therefore, the electrical insulation properties in the areas B between the collars 11 and the bolts 5 and the metal washers 6 do not deteriorate even if foreign matter, such as splashes, adheres to the heads 5a of the bolts 5 and the metal washers 6 covered by the insulating cover 10.

[0046] Furthermore, the tubular portion 10b of the insulating cover 10 covering the hollow bore 41a prevents foreign matter from adhering to the inner peripheral surface of the hollow bore 41a and an inner peripheral surface of the hollow portion 2d. Accordingly, the inner peripheral surface of the hollow bore 41a can be prevented from being electrically connected to the inner peripheral surface of the hollow portion 2d in a region C.

[0047] Furthermore, in the case where the insulating cover 10 is elastically deformable, the close contact of the insulating cover 10 with the outer peripheral surface of the supply member A and the inner peripheral surface of the hollow bore 41a due to the elastic restoring force can more reliably prevent the intrusion of foreign matter such as splashes. This more reliably prevents deterioration of the electrical insulation properties between the holder body 4 and the robot body 2.

[0048] Particularly, in the case where the inner surface of the holder body 4 is uneven, for example, in the case where the inner surface is a cast surface, the deformation of the flat portion 10a according to an uneven shape of the inner surface of the base end wall 41 prevents the formation of a gap between the flat portion 10a and the inner surface of the base end wall 41. Accordingly, the insulating cover 10 can reliably cover locations through which foreign matter might penetrate into the areas B and C.

[0049] Furthermore, in this embodiment, due to the electrical insulation of the holder body 4 from the robot body 2, no electrical insulation is required between the holder body 4 and the tool 3. Therefore, an operator can attach and detach the tool 3 to the tool mounting surface 4b without having to perform additional work to ensure electrical insulation between the tool 3 and the robot body 2.

[0050] By providing an insulating member between the holder body 4 and the tool 3, current can also be prevented from flowing from the tool 3 into the robot body 2. However, in this case, the insulating member must also be attached and detached when attaching the tool 3 to the tool mounting surface 4b and when detaching the tool 3 from it, thereby increasing the number of components and work to be handled.

[0051] Furthermore, in this embodiment, the holder 1 itself is provided with an insulating structure that isolates the holder 1 from the robot body 2, and the holder 1 is fixed to the tool mounting surface 2a, separated from it only by the thin insulating plate 9. This makes it possible to suppress the offset from the tool mounting surface 2a to the tool mounting surface 4b, the total weight of the parts to be fixed to the tool mounting surface 2a, and the cost.

[0052] It is also possible to electrically insulate the holder 1 from the robot body 2 by placing an insulating member between the tool mounting surface 2a and the holder 1 and attaching the holder 1 to the insulating member instead of the tool mounting surface 2a. However, in this case, a thick insulating member is required, increasing the offset amount, overall weight, and cost.

[0053] As described above, by simply fastening the bolts 5 to the threaded holes 2c of the tool mounting surface 2a, the holder body 4 can be electrically insulated from the tool mounting surface 2a, and the insulating cover 10 can be attached to the holder body 4. Therefore, it is possible to perform the attachment of the holder 1 to the arm member 2b and the attachment of the insulating cover 10 to the holder body 4 in one step, which has the advantage of reducing the number of fasteners and the complexity of the attachment work.

[0054] It should be noted that although the insulating sleeves 7 and the insulating washers 8 are provided separately in this embodiment, the components can also be formed integrally. Furthermore, the insulating plate 9 can be provided as part of the robot body 2 or as part of the holder body 4. Furthermore, the insulating plate 9 can be formed integrally with the insulating sleeves 7.

[0055] Furthermore, by arranging the metal washers 6, which have the same outer diameter dimensions as the insulating washers 8, so that they rest on the insulating washers 8, the forces received from the heads 5a of the bolts 5 can be distributed by the metal washers 6 over the entire surface of the insulating washers 8, thereby preventing breakage of the insulating washers 8 due to stress concentration. Alternatively, the metal washers 6 can be omitted if the insulating washers 8 are formed of a material with sufficient strength.

[0056] Furthermore, in the above-described embodiment, a configuration may be adopted in which the collars 11 are attached to the counterbores 12 of the holder body 4, and the holder body 4 and the arm member 2b may be aligned by pins or the like.

[0057] Since in this case gaps are formed between the through holes 41b of the holder body 4 and the outer peripheral surfaces of the bolts 5 as well as between the inner holes 11c of the collars 11 and the outer peripheral surfaces, the insulating sleeves 7 can be omitted.

[0058] Moreover, although the insulating cover 10 in the above-described embodiment has the tube portion 10b covering the inner peripheral surface of the hollow hole 41a, in the case where it is possible to cover the hollow hole 41a only with the flat portion 10a, the insulating cover 10 may not necessarily have the tube portion 10b.

[0059] In particular, in the case where an inner peripheral surface of the flat portion 10a is in contact with the outer peripheral surface of the supply member A, and the gap between the inner peripheral surface of the hollow bore 41a and the outer peripheral surface of the supply member A is closed by the flat portion 10a, only the flat portion 10a can prevent foreign matter from entering the hollow bore 41a. Therefore, in such a case, the pipe portion 10b can be omitted.

[0060] Furthermore, the insulating cover 10 in the embodiment described above does not necessarily have to be elastically deformable. For example, the insulating cover 10 can be formed from a rigid material.

[0061] In the case where the insulating cover 10 is an elastically deformable member such as a sponge, even if the lengths of the small-diameter holes 13a of the through-holes 13 are not precisely determined, it is possible to achieve both the fixing of the insulating cover 10 and the fixing of the holder 1 to the arm member 2b due to the elastic deformation of the insulating cover 10.

[0062] Furthermore, if the insulating cover 10 is an elastically deformable member, such as a sponge, the insulating cover 10 can be easily inserted into the holder body 4 from the window 43a. On the other hand, if the insulating cover 10 is not elastically deformable, it may be difficult to pass the insulating cover 10 through the window 43a. In this case, the insulating cover 10 can be divided into a plurality of elements whose dimensions allow the elements to pass through the window 43a.

[0063] Furthermore, the one-piece insulating cover 10 in this embodiment has the through holes 13 with the two-stage structure including the small-diameter holes 13a and the large-diameter holes 13b. Alternatively, as shown in Fig. 6, the insulating cover 10 may be divided in two in the thickness direction, wherein large-diameter holes (second through-holes) 13b may be provided in an insulating cover (second cover) 10A, which is one of the divided insulating covers, and small-diameter holes (first through-holes) 13a may be provided in an insulating cover (first cover) 10B, which is the other divided insulating cover. Then, by combining the two insulating covers 10A and 10B in a stacked state, the through-holes 13 are formed with the two-stage structure shown in FIG. Fig. 5 formed.

[0064] In this case, the two insulating covers 10A and 10B can be secured together in a stacked state by adhesive or similar means. Accordingly, it is sufficient for each of the insulating covers 10A and 10B to have through holes with uniform diameter dimensions, with the diameter dimensions being different between the insulating covers 10A and 10B; therefore, their processing is simple.

[0065] Furthermore, in this embodiment, the flange portions 11b of the collars 11, the insulating washers 8, and the metal washers 6 are stacked into the large-diameter holes 13b of the through-holes 13 in the insulating cover 10. Alternatively, as shown in Fig. 7, the metal discs 6 are exposed outside the large-diameter holes 13b. In this way, the insulating washers 8 also make it possible to prevent deterioration of the electrical insulation properties between the metal discs 6 and the collars 11 due to the adhesion of splashes or the like.

[0066] In addition, in this case, as in Fig. 8, the metal discs 6 can be configured to hold down the surface of the insulating cover 10 by setting the outer diameter dimensions of the metal discs 6 sufficiently larger than the inner diameter dimensions of the through holes 13. Accordingly, the insulating cover 10 does not need to be held by the flange portions 11b of the collars 11; therefore, it is possible to facilitate the manufacture of the insulating cover 10 and the collars 11 by forming the collars 11 in a simple cylindrical shape and the through holes 13 as holes with a simple circular cross-section having a single inner diameter dimension.

[0067] Furthermore, instead of holding the insulating cover 10 by the metal washers 6, the insulating washers 8 may be configured to have outer diameter dimensions corresponding to those of the metal washers 6 and larger than the inner diameter dimensions of the through holes 13, as shown in Fig. 9. Accordingly, the insulating cover 10 can be held down by the insulating washers 8, and in this way, the shapes of the insulating cover 10 and the collars 11 can also be simplified.

[0068] In addition, instead of the bolts 5 and the metal discs 6, flanged bolts 14 can also be used as holder fastening devices, in which the heads 14a and the flanges 14b of the bolts are formed in one piece, as in Fig. 10. The flanges 14b of the flanged bolts 14 can hold down the insulating cover 10 and close the through holes 13.

[0069] Furthermore, in this embodiment, although the collars 11 are formed of a high-strength material, such as steel, collars 15 made of a material with electrical insulating properties may be used, provided sufficient strength is ensured. For example, as shown in Fig. 11 illustrates that by using collars 15 provided with flanges 15a, the insulating sleeves 8, the insulating sleeves 7 and the metal discs 6 are made superfluous, so that the shape of the through holes 13 of the insulating cover 10 can be simplified, which facilitates manufacture.

[0070] In addition, as in Fig. 12 illustrates that the collars 15, which are made of a material with electrical insulating properties, can also be formed in a simple cylindrical shape by combining them with the metal discs 6.

[0071] In addition, although the counterbores 12 into which the collars 11 or 15 are inserted are provided in the inner surface of the holder body 4, the counterbores 12 against which the distal ends of the collars 11 or 15 abut may be omitted alternately if the inner surface of the holder body 4 is formed as a machined seat.

[0072] Furthermore, in the above-described embodiment, as shown in Fig. 13, the holder 1 may additionally comprise an annular clamp 16 arranged in the hollow bore 41a and fixing the supply element A with respect to the tool fixing surface 2a.

[0073] Terminal 16 has, as shown in Fig. 14, two semi-arc-shaped components 16a and 16b, by which the supply element A is held in the radial direction. An elastic body 17 is wound around the outer peripheral surfaces of the supply element A, and the elastic body 17 is arranged between the supply element A and the clamp 16.

[0074] The two components 16a and 16b are fixed in close contact with the outer peripheral surface of the supply element A, from which they are separated by the elastic body 17. The components 16a and 16b are secured, for example, by screwing bolts 16c into the screw holes 16d of the components 16a and 16b. The clamp 16 is secured to the tool mounting surface 2a with bolts (not shown).

[0075] Since in Fig.13, a space between the inner peripheral surface of the hollow bore 41a and the outer peripheral surface of the supply member A is closed by the clamp 16 and the elastic body 17, a gap may be present between the hollow bore 10c of the insulating cover 10 and the outer peripheral surface of the supply member A, and the insulating cover 10 may not include the tubular portion 10b. The flat portion 10a extends further inward in the radial direction than the outer peripheral surface of the clamp 16 and completely covers the inside of the clamp 16.

[0076] In this configuration, movements of the supply element A in the holder body 4 can be suppressed by fixing the supply element A in the hollow bore 41a of the base end wall 41.

[0077] Furthermore, in the above-described embodiment, although the holder 1 is used to fix a hollow or solid tool 3 to the hollow arm member 2b, the holder 1 can be alternately used to fix a hollow tool 3 to a non-hollow arm member 2b. In this case, the holder 1 can be provided as part of the welding device. In other words, the welding device according to this embodiment comprises the holder 1 and the hollow welding tool 3.

[0078] The hollow welding tool 3 is fixed to the robot mounting surface 4a provided with the hollow bore 41a by the bolts 5 and the metal washers 6, and the tool 3 and the holder body 4 are electrically insulated from each other by the insulating sleeves 7, the insulating washers 8, and the insulating plate 9. At least one supply element A is guided via the hollow bore 41a between the hollow portion of the tool 3 and the interior of the holder body 4. The holder body 4 is fixed to the tool mounting surface 2a of the arm member 2b, which is not hollow at the tool mounting surface 4b. In this case, the distal end wall 42 need not have a window 42a and may also include through holes (not shown) instead of the threaded holes 42b.

[0079] Furthermore, in the embodiment described above, the holder 1 can be provided as part of the welding robot system. In other words, the robot system according to this embodiment comprises the robot 20 with the holder 1 and the robot body 2, as well as the welding device with the tool 3, e.g., a welding gun. The welding device is attached to the distal end of the robot body 2, from which it is separated by the holder 1. {Reference symbol list} 1 holder 2 robot bodies 2a Tool mounting surface 2b Arm limb at the distal end 2c threaded hole 2d hollow section 3 tools, welding tools 4 holder bodies 5 bolts (holder fastening device) 5a, 14a head 6 Metal disc (holder fastening device) 8 insulating washer (insulating element) 10, 10A, 10B Insulating cover (first cover, second cover) 11, 15 collar 11a Small diameter section 11b Flange section 13a Small diameter hole (first through hole) 13b Large diameter hole (second through hole) 14 flanged bolt (holder fastening device) 16 terminal 20 robots 41a Through hole 41b Through hole A Supply element attachment device QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 62-142083

[0003] JP 2013-202697

[0003] JP 11-114873

[0003] JP 5344315

[0003] JP 08-047886

[0003]

Claims

[1] Holder, comprising: a holder body having a hollow structure and fixed to a tool mounting surface of a hollow arm member with an insulating plate having electrical insulating properties interposed therebetween; Insulating members that electrically insulate the holder fastening devices that secure the holder body to the tool mounting surface from the inside of the holder body and the holder body from each other; and an insulating cover having electrical insulating properties and disposed within the holder body, wherein the holder body, the insulating plate and the insulating cover each have a hollow bore through which a supply element is passed from the inside of the arm member via an opening in the tool fastening surface into the interior of the holder body, the holder fastening means comprise one or more bolts which are fastened to the threaded holes provided in the tool fastening surface by passing them through the through holes in the holder body, in the insulating plate and in the insulating cover, and The insulating cover covers a gap between the hollow bore of the holder body and the supply element and is attached to the holder body by fastening the bolts. [2] A holder according to claim 1, further comprising cylindrical collars arranged in the through-holes of the insulating cover through which the respective bolts are passed, and held in an axial direction by the heads of the respective bolts and the holder body therebetween, wherein the insulating members comprise insulating washers which are held by the ends of the collars on one side thereof in the axial direction and the heads of the bolts and which are brought into close contact with the inner peripheral surfaces of the through holes of the insulating cover over an entire circumference of the through holes. [3] A holder according to claim 1, wherein the insulating members comprise cylindrical collars having electrical insulating properties which are arranged in the through-holes of the insulating cover through which the respective bolts are passed and which are held in the axial direction by the heads of the respective bolts and the holder body. [4] Holder according to one of claims 1 to 3, wherein the insulating cover is elastically deformable. [5] A holder according to any one of claims 1 to 4, further comprising an annular clamp disposed in the hollow bore and securing the supply element with respect to the tool mounting surface. [6] Holder according to claim 2, wherein: the collars comprise small-diameter sections and flange sections projecting radially outward from the end portions of the small-diameter sections on one side; and the through holes of the insulating cover have a stepped shape, wherein the outer peripheral surfaces of the small diameter portions of the collars and the outer peripheral surfaces of the flange portions of the collars are respectively inserted into the through holes. [7] The holder according to claim 6, wherein the insulating cover is formed by stacking a first cover having first through holes to which the outer peripheral surfaces of the small diameter portions of the collars are attached, and a second cover having second through holes to which the outer peripheral surfaces of the flange portions of the collars are attached. [8] Robots, including: a robot body having at least one arm member, the arm member being hollow at its distal end; and the holder according to one of claims 1 to 7. [9] Welding device comprising: the holder according to one of claims 1 to 7; and a hollow welding tool, where the welding tool is attached to an outer surface of the holder body, wherein the outer surface is provided with the hollow bore, and at least one supply element is guided between a hollow portion of the welding tool and the interior of the holder through the hollow bore. [10] Robot system comprising: the robot according to claim 8; and a tool attached to the distal end of the robot body and separated from it by the holder.

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