Robot and linear-shaped-item treating structure thereof

A robot includes at least one cover member disposed on outside in a direction of an axis of a second wrist unit that rotatably supports a tip-most first wrist unit, to which a tool is fixed, around a predetermined axis. The cover member includes a recessed part obtained by recessing at least a part of an outer peripheral edge around the axis in the direction of the axis. A fastener is provided to fix a plate that holds a linear-shaped item in a direction along the axis between the recessed part and the fastener.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority to Japanese Patent Application No. 2017-248088, filed on Dec. 25, 2017, the entire content of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a robot and a linear-shaped-item treating structure thereof.

BACKGROUND OF THE INVENTION

In order to supply power or fluid to a tool such as a hand mounted on a wrist tip of a robot, a linear-shaped item such as a cable and a tube is laid on an outer surface of the robot to be outfitted up to the wrist tip of the robot (for example, refer to Japanese Unexamined Patent Application, Publication No. 2015-24473). Generally, the linear-shaped item is fixed to an outer peripheral surface of the robot at a wrist of the robot by a sheet metal for a clamp or the like so as not to get entangled or not to wildly move by motion of the robot.

SUMMARY OF THE INVENTION

An aspect of the present invention is directed to a robot including: at least one cover member disposed on outside in a direction of an axis of a second wrist unit that rotatably supports a tip-most first wrist unit, to which a tool is fixed, around a predetermined axis, wherein the cover member includes a recessed part obtained by recessing at least a part of an outer peripheral edge around the axis in the direction of the axis, and a fastener provided to fix a plate that holds a linear-shaped item in a direction along the axis between the recessed part and the fastener.

Another aspect of the present invention is directed to a linear-shaped-item treating structure of a robot including: a plate disposed so as to hold the linear-shaped item between the plate and the recessed part of the above robot; and a fastening member that fixes the plate by using the fastener of the cover member.

DESCRIPTION OF EMBODIMENT(S) OF THE INVENTION

A robot and a linear-shaped-item treating structure10according to an embodiment of the present invention will be hereinafter described with reference to the drawings.

The robot according to this embodiment may be a robot having an arbitrary axis constitution. The robot includes, for example, a wrist1three-dimensionally movable with respect to a base fixed to a floor surface by three joint axes, in a case of a six-axis articulated type.

As illustrated inFIG. 1, the wrist1of the robot includes a tip-most first wrist unit3that rotates a tip member2, to which a tool T is fixed, around a first axis A, a second wrist unit4that rotates the first wrist unit3around a second axis (axis) B orthogonal to the first axis (axis) A, and a third wrist unit (not illustrated) that rotates the second wrist unit4around a third axis orthogonal to the second axis B. Consequently, the tool T fixed to the tip member2can be set to an arbitrary attitude.

As illustrated inFIG. 1, the robot according to this embodiment includes a cover member8including recessed parts6and taps (fastener)7on an outer surface on both ends in the second axis B direction of a housing5constituting the second wrist unit4.

The second wrist unit4includes a motor and a reducer (not illustrated) housed in the housing5.

The recessed parts6each are a portion obtained by partially recessing a central part in the width direction of a tip edge (outer peripheral edge) of the housing5, in the second axis B direction. In the example illustrated inFIG. 1, each recessed part6is configured by an inclined surface tapered toward the tip.

The taps7are machined in two bearing surfaces provided at two portions on both sides in the width direction of each recessed part6. In the example illustrated inFIG. 1, the taps7are formed on a base end side with respect to each recessed part6.

As illustrated inFIG. 2, the linear-shaped-item treating structure10according to this embodiment includes the robot ofFIG. 1, a plate11, and bolts (fastening members)12fastened to the taps7. A cable13is disposed between the plate11and the recessed part6, the bolts12are fastened to the taps7, so that the plate11is fixed to the cover member8, and the cable13is supported.

As illustrated inFIG. 2, the plate11is, for example, a metal plate member pressed in a U-shape, and includes two through holes11athat penetrate the bolts12.

As illustrated inFIG. 3, the bolts12are fastened to the taps7, so that the plate11is fixed to the bearing surfaces of the robot, and is disposed so as to block a part of the recessed part6. In a portion where the recessed part6is blocked, the cable (linear-shaped item)13is radially held between the plate11and the recessed part6. Additionally, the cable13is outfitted so as to extend to the outside and the inside of the recessed part6through a portion where the plate11is not blocked.

According to the robot and the linear-shaped-item treating structure10thereof thus configured according to this embodiment, as illustrated inFIG. 3, the cable13that is outfitted so as to be laid on the outside of the robot, and extends from the base end side along an outer surface of the cover member8can be fixed so as to pass through the recessed part6provided on the tip edge of the cover member8. Consequently, even when the second wrist unit4is activated, and the tool T mounted on the tip member2of the first wrist unit3is moved, the cable13connected to the tool T can be supported so as not to get entangled or so as not to wildly move.

When the cable13is fixed, the cable13is disposed so as to pass through the recessed part6, the plate11is disposed such that the cable13is held between the recessed part6and the plate11, and the plate11is fixed to the housing5by fastening the bolts12to the taps7.

The recessed part6is partially recessed at a center in the width direction of the tip edge, and therefore the cable13can be temporarily fixed so as not to fall from the recessed parts6in the width direction even before the plate11is fixed.

The robot and the linear-shaped-item treating structure10thereof according to this embodiment, the dimension D1in the direction along the second axis B of the second wrist unit4after the cable13is outfitted is the dimension obtained by addition of the diameter of the cable13to the dimension of the housing5, as illustrated inFIG. 4.

On the contrary, in a conventional method of fixing the cable13to the plate11fixed to the housing5by a nylon band20or the like, as illustrated inFIG. 5, the dimension D2in the direction along the second axis B of the second wrist unit4after the cable13is outfitted is a total of the height dimension of the bearing surface, the thickness dimension of the plate11fixed to the bearing surface, the diameter dimension of the cable13, and the thickness dimension of the nylon band20. As a result, according to the robot and the linear-shaped-item treating structure10according to this embodiment, the dimension in the direction along the second axis B of the second wrist unit4including the cable13can be largely reduced compared to the conventional method.

That is, even in a case where the tool T fixed to a tip surface of the wrist1is inserted into a narrow space along with the wrist1, this dimension has an advantage that a possibility of interference of the wrist1and the cable13with a peripheral device can be remarkably reduced.

In this embodiment, the bolts12that fix the plate11are disposed on the base end side with respect to the portion that suppresses the cable13. Consequently, as illustrated by broken lines inFIG. 4, head parts of the bolts12fastened to the taps7can be each disposed at a position lower than the cable13. As a result, it is possible to prevent increase by the head parts of the bolts12of the dimension in the direction along the second axis B of the second wrist unit4to which the cable13is fixed.

In this embodiment, the plate11is fixed such that the cable13disposed in the recessed part6is held between the recessed part6and the plate11. However, in this case, as illustrated inFIG. 4, an elastic member14such as a sponge is compressed between the plate11and the cable13, so that it is possible to more simply fix the cable13.

In this embodiment, the recessed part6is partially provided only at the center in the width direction of the housing5. However, in place of this, as illustrated inFIG. 6, an inclined surface15may be disposed on an overall tip edge of the housing5. Consequently, it is also possible to reduce the dimension D3in the direction along the second axis B of the second wrist unit4including the cable13.

The positions of the taps7are provided on the base end side with respect to the recessed part6. However, the taps7may be disposed at such positions as to hold the recessed part6therebetween in the width direction of the housing5. Consequently, the shape of the plate11that suppresses the cable13can be a simple band plate shape. Consequently, there is an advantage that the cable13can be more reliably supported.

In this embodiment, the cable13is exemplified as the linear-shaped item. However, in place of this, the linear-shaped item may be used in order to fix a linear-shaped item such as a tube which supplies liquid, a wire, or the like to the tool T.

As the plate11, a metal plate member is exemplified. However, in place of this, as illustrated inFIG. 7, a member having a shape curved along an inclined surface of the recessed part6may be employed. Consequently, it is possible to further suppress a projection amount in the second axis B direction in the vicinity of the tip of the wrist1, and further reduce a possibility of interference with a peripheral device.

In this embodiment, the recessed part6is provided in the tip edge of the housing5. However, as illustrated inFIG. 8, the recessed part6may be provided in an edge in the width direction of the housing5.

The number and the position of the taps7may be an arbitrary number and an arbitrary position.

The fasteners are constituted by the taps7. However, in place of this, the fasteners provided in the cover member8is constituted by stud bolts, and nuts may be employed as the fastening members.

As a result, the above-described embodiment leads to the following aspects.

An aspect of the present invention is directed to a robot including: at least one cover member disposed on outside in a direction of an axis of a second wrist unit that rotatably supports a tip-most first wrist unit, to which a tool is fixed, around a predetermined axis, wherein the cover member includes a recessed part obtained by recessing at least a part of an outer peripheral edge around the axis in the direction of the axis, and a fastener provided to fix a plate that holds a linear-shaped item in a direction along the axis between the recessed part and the fastener.

According to this aspect, the linear-shaped item that is wired so as to be laid on the outer surface of the robot passes in the vicinity of the axis of the second wrist unit of the robot, and thereafter is disposed so as to pass through the recessed part provided in at least the part of the cover member at the outer peripheral edge around the axis, the plate is disposed so as to hold the linear-shaped item between the recessed part and the plate, and the plate is fixed to the cover member by using the fastener provided in the cover member, so that the tip side of the linear-shaped item is outfitted so as to extend in the radial direction with respect to the axis of the second wrist unit. Consequently, even when the tip-most first wrist unit, to which the tool connected to the tip of the linear-shaped item is fixed, is rotated around the axis by the second wrist unit, the linear-shaped item can be supported so as not to get entangled or so as not to wildly move.

In this case, in the vicinity of the axis of the second wrist unit, the linear-shaped item projects to the outside in the direction of the axis with respect to the outer surface of the second wrist unit by the thickness of the second wrist unit. However, in the outer peripheral edge of the second wrist unit, the projection amount is reduced by passing of the linear-shaped item through the recessed part of the cover member. Consequently, it is possible to suppress increase of a contour shape of the wrist part by mounting of the linear-shaped item, and reduce a possibility of interference of the wrist part with a peripheral device.

In the above aspect, the recessed part may be provided by partially recessing a part of an outer peripheral edge in a circumferential direction around the axis of the cover member over a predetermined width dimension W.

Thus, on both ends in the circumferential direction of the recessed part obtained by partially recessing the outer peripheral edge, side walls are disposed at such positions as to radially hold the linear-shaped item housed in the recessed part, and therefore the linear-shaped item held between the plate and the recessed part can be simply prevented from being radially deviated.

Another aspect of the present invention is directed to a linear-shaped-item treating structure of a robot including: a plate disposed so as to hold the linear-shaped item between the plate and the recessed part of the above robot; and a fastening member that fixes the plate by using the fastener of the cover member.

According to the present invention, an effect capable of suppressing increase of a contour shape of a wrist part by mounting of a linear-shaped item, and reducing a possibility of interference of the wrist part with a peripheral device is produced.