JP3830488B2 - Wiring and piping processing equipment - Google Patents

Description

  The present invention relates to a wiring / piping apparatus applied to the periphery of a member having a first member and a second member that rotate relative to each other about a predetermined axis. The wiring / piping apparatus according to the present invention is typically used for electric wiring and fluid supply pipe piping at the wrist of an industrial robot. In the present specification, the expression “wiring / piping” is used as a term indicating “a linear body including at least one of wiring and piping”. Examples of this striated body include “a cable including a plurality of electrical wirings and a plurality of fluid pipings”, “a cable including a plurality of electrical wirings and one fluid piping”, and “a plurality of electrical wirings only”. Including cables "and" cables including only a plurality of fluid pipes ".

  For example, a wrist portion of an industrial robot (hereinafter simply referred to as a robot) has a structure having a first member and a second member that rotate relative to each other about a predetermined axis. Several prior arts are already known for such wiring and piping processing around the relative rotating portion, and typical examples thereof are shown in FIGS. 1 (first conventional example) to FIG. 3 (third conventional example). )Pointing out toungue.

  First, in the first conventional example shown in FIGS. 1A and 1B, a cable (wire) is formed by utilizing a cylindrical gap formed between an outer member A and an inner member B which are concentric and relatively rotate. It is laid so that W folds back in a U-shape. That is, one member (here, the outer member A) is provided with the fixed side fixing portion C, and the other member (here, the inner member B) is provided with the movable side fixing portion D, and the fixed side fixing portion C and the movable side fixing portion are fixed. The cable W is supported by the part D, and the cable W is stretched with a margin in length between them to form a U-shaped folded portion in the cylindrical gap.

  Sometimes cable tracks and conduits are used together. Further, as shown in FIG. 1A, the U-shaped folded portion is formed by folding in the circumferential direction in a plane perpendicular to the relative rotation axis, as shown in FIG. 1B. Thus, it may be formed along the cylindrical surface. This type of technology is described in, for example, Patent Document 1 and Patent Document 2 below.

  Next, in the second conventional example shown in FIG. 2, a cable W is laid in the longitudinal direction along the rotation axis of the outer member A and the inner member B that are concentrically and relatively rotated, and one member (here, the outer member A) is laid. ) Is provided with a fixed side fixing portion C, and a movable side fixing portion D is provided on the other member (in this case, the inner member B), and the cable W is supported by the fixed side fixing portion C and the movable side fixing portion D. In some cases, the cable W is bent into a two-letter shape, an S-shape or a Z-shape near one or both of the fixed-side fixed portion C and the movable-side fixed portion D. This type of technology is described in, for example, Patent Documents 3 to 5 listed below.

  Further, in the third conventional example shown in FIG. 3, a cable W is laid in a coil shape around the rotation shafts of the outer member A and the inner member B that are concentrically and relatively rotated, and one member (here, the outer member A). Is provided with a fixed side fixing portion C, and a movable side fixing portion D is provided on the other member (inner member B in this case). This type of technology is described in, for example, Patent Document 6 and Patent Document 7 below.

Japanese Patent No. 2647700 Utility Model Registration No. 2597287 JP 2001-353684 A Japanese Patent Application Laid-Open No. 08-197482 Utility Model Registration No. 2553843 Japanese Patent Application Laid-Open No. 08-1212796 Japanese Patent Laid-Open No. 05-116090

However, the conventional techniques have the following problems (1) to (3).
(1) In the U-shaped folding method (first conventional technology), a large space is required as a whole in order to form the U-shaped folded portion with a sufficiently small curvature. If it is intended to be applied when the gap between the inner and outer members A and B is narrow, the curvature of the U-shaped folded portion is increased, the cable W is forced, and the life of the cable W is shortened.

  (2) In the method of fixing both ends in the longitudinal direction along the rotation axis (second prior art), unless the distance for torsional absorption is sufficiently long, the life becomes extremely short. For example, if the robot arm has a certain size, it is easy to secure a long space for absorbing torsion, but at the robot's wrist tip, etc., take sufficient space with a linear length. Is difficult.

  (3) In the method using the coil processing (third prior art), if the number of coil turns is reduced, the coil diameter changes greatly, and a large space is required in the radial direction when the inner and outer members A and B are relatively rotated. It becomes. Moreover, when there are many winding numbers, a long wire is needed for that purpose. Further, when the number of wires included in the cable W (the number of cores) is large or when thick wiring or piping is included, there is a problem that it is difficult to process the cable W into a coil shape.

  Therefore, the object of the present invention is to solve the problems of the prior art as described above, and can be easily applied to a part having inner and outer members that rotate relative to each other, such as a joint part of a robot, particularly a wrist part, and saves space. Therefore, it is intended to enable wiring / pipe processing without any trouble even when a large movable range (for example, 360 degrees or more) is required for the inner and outer members.

  The present invention includes at least one of wiring and piping between a first member and a second member that rotate relative to each other about a predetermined axis, and one end is held by the first member and the other end is the second member. The present invention is applied to a wiring / pipe processing apparatus for attaching a plurality of filaments held by a member. Here, the first member and the second member are members that typically constitute a part of the robot body, and may be members used for the wrist portion of the robot.

  According to the basic feature of the present invention, the inner pipe member having a different diameter and the outer pipe member are partially connected to each other via the connecting member so that the inner and outer pipe members are fixed in a substantially concentric relative positional relationship. The double-structure pipe member is attached to the first member so that the center axis of the double-structure pipe member substantially coincides with the center axis of the relative rotation. Then, the plurality of filaments are divided into a first group and a second group, the filaments belonging to the first group are passed through the hollow portion of the inner pipe member, and the filaments belonging to the second group A body is disposed through a gap between the inner pipe member and the outer pipe member.

  In this way, the pipe through which the striate body passes has a double structure, the striate body is divided into the first group and the second group, and the first group is formed in the hollow portion of the inner pipe member in the pipe member of the same double structure. Through the passage of the second group through the gap between the inner pipe member and the outer pipe member, the striate body does not float more than necessary in the pipe. Along with this, early disconnection caused by the fact that the striate body that is weak against twisting approaches the center is avoided. In addition, abnormal wear due to rubbing between those having a large surface friction can be prevented.

In the present invention, the linear member belonging to the second group is not wound around the inner pipe member when the first member is in a predetermined relative rotational position with respect to the second member, When the first member is in a position rotated rightward from the predetermined relative rotational position when viewed from the second member side, the first member is wound clockwise along the outer surface of the inner pipe member, and left from the predetermined relative rotational position. when in the rotated position to wind around the left-handed along the outer surface of the inner pipe member.

  In addition, it is preferable that the linear body which belongs to the said 2nd group is wiring and piping with a smaller bending radius than the linear body which belongs to the said 1st group. Further, the inner surface and outer surface of the inner pipe material, and the inner surface of the outer pipe material, which are in contact with the linear body, are subjected to surface treatment for preventing wear, and the linear body is damaged by friction. And may prevent wear. Alternatively, for the same purpose, a collar made of a low friction material may be inserted along at least a part of the inner and outer surfaces of the inner pipe material and the inner surface of the outer pipe material.

  As described above, in the present invention, a plurality of striatums are classified into two groups and processed. In this classification, tubes having a large bending radius (that is, relatively hard and difficult to bend) are passed inside. It is possible to select a tube having a small bending radius (that is, relatively soft and easy to bend) through the outside. In addition, in the electrolytic wiring, it is possible to select such that a wire material resistant to twisting is passed inside and a wire material weakly twisted is passed outside.

  These groupings are preferably determined so as to have the longest lifetime depending on the configuration of the striatum. In general, a linear body such as a tube or a cable disposed on the outer side is bent by being partially wound around the inner pipe, so that a longer life can be achieved than a simple twisting operation.

  According to the present invention, for example, the wiring and piping in the periphery of two members that rotate relative to each other around a predetermined axis, such as a wrist portion of a robot, can be protected from fatigue due to bending or twisting, and the life can be increased. As a result, the user can use the wiring and piping without exchanging them for a long period of time, thereby reducing the cost of parts and maintenance.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. First, referring to FIGS. 4 and 5, FIG. 4 shows a cross-sectional view along the axis of the main structure of the wiring and piping apparatus according to the embodiment, and FIG. 5 uses a double pipe in the wiring and piping apparatus. The state of the wiring and piping processing that was performed is represented by a diagram viewed from the axial direction. The structure shown in FIG. 4 is used, for example, in the wrist portion of a robot. Reference numeral 2 denotes a member (second member) constituting the stationary housing, and reference numeral 3 denotes a member (second member) constituting the moving housing. 1 member).

  A pipe member 12 is attached to the moving housing 3 by a mounting portion 25 using screws, and the pipe member 12 is rotatably supported by the cylindrical fixed housing 2 via a bearing 4. . As a result, the pipe member 12 and the moving housing 3 are supported rotatably around the shaft 1 of the cylindrical fixed housing 2.

  As illustrated in FIG. 5, another pipe member 11 is provided on the inner side of the pipe member 12 so as to be substantially concentric with the pipe member 12. 13 are connected. In other words, the outer pipe member 12 and the inner pipe member 11 constitute a double-structured pipe member connected in a substantially concentric relationship. And the pipe member of the double structure which integrated this outer pipe material 12 and the inner pipe material 11 is rotatable around the rotating shaft 1 by the above-mentioned support structure.

The wiring / piping extends from a holding portion 23 provided on the fixed housing 2 to a holding portion 24 provided on the moving housing 3. As shown in FIG. 5, the wiring / pipe shown by reference numeral 21 is a group of linear bodies (first group; however, one piece passing through the hollow portion of the inner pipe member 11 of the pipe member having the double structure. This is also possible in the case of a striate body.
On the other hand, as shown in FIG. 5, the wiring / pipe indicated by reference numeral 22 is a space between the outer pipe member 12 and the inner pipe member 11 (thick cylindrical space; However, it represents a striate group (second group; however, there may be one striate) passing through the connecting member 13 portion).

These wires / pipes 21 and 22 are held by the holding housing 23 in the stationary housing 2 and held by the holding housing 24 in the moving housing 3. Here, as shown in FIGS. 8A and 8B, the holding portions 23 and 24 can be fixed by a binding band 27 or a fixing member 28 so that the wiring / pipe 26 does not move.
Further, as shown in FIG. 9, the holding member 29 is arranged so that the wiring / piping 26 can be slid in the arrangement direction, or can be rotated around the axis in the arrangement direction, and can be slid and rotated. It is good also as a structure which restrains.

The wires / pipes 21 and 22 are stretched so that each wire body has an appropriate slack (length margin) in preparation for the rotation of the moving housing 3 to be described next. The behavior of the wiring and piping during the rotation of the moving housing 3 is schematically shown in FIG.
In FIG. 6, the striatum belonging to the first group is represented by reference numeral 21, and the striatum belonging to the second group is represented by reference numeral 22. First, in the neutral state (rotation zero) shown in FIG. 6B, the inner first group of linear members 21 are substantially straight from the holding portion 23 on the stationary housing 2 to the inside of the inner pipe member 11. And is pulled out toward the holding portion 24 (not shown in FIG. 6) on the moving housing 3.

The outer second group of linear members 22 passes substantially linearly between the inner pipe member 11 and the outer pipe member 12 from the holding part 23 on the stationary housing 2, and the holding part 24 on the moving housing 3. It is drawn toward (not shown in FIG. 6).
However, as described above, the neutral wires / pipes 21 and 22 have moderate slack in preparation for the rotation of the moving housing 3.

  6 (a) and 6 (c), when the movable housing 3 is rotated clockwise as viewed from the right axial direction in FIG. It winds right-handed around the material 11 and turns left-handed when it rotates counterclockwise. As for the inner first group of striated bodies 21, the passing position slightly fluctuates with the movement of the holding portion 24 on the moving housing 3, but the amount is small. However, since the twist associated with the movement of the holding portion 24 is larger than that of the second group of line bodies 22, it is better that linear bodies weak against twisting belong to the second group.

  If moderate slack is ensured for each striate body, particularly the striate body 22 belonging to the second group, axial movement over a considerably large angle (for example, about plus or minus 360 degrees) can be achieved without difficulty. However, if the slack is increased in order to expand the rotation movable range, the filaments come into contact with the edge or outer surface of the inner pipe member 11, the inner surface of the outer pipe member 12, etc., and the operation is restricted. May cause trouble. In addition, even if the operation is possible, rapid wear occurs at the contact portion, which may shorten the life of the wiring / pipe.

  In order to avoid such a situation, for example, as shown in FIG. 7, a collar 14 made of a material having a low friction coefficient may be attached to the pipe material 12 or 11. Alternatively, the inner and outer surfaces of the inner pipe member 11 and the inner surface of the outer pipe member 12 may be subjected to surface treatment for preventing wear. There are various forms of these low friction coefficient materials or surface treatments for preventing wear, and since all are well known, details thereof will not be described here.

  In addition, it is preferable that the above-described grouping of wiring / piping (striate bodies) is selected so that the lifespan of each striate body is as long as possible. Generally speaking, it is preferable that the wire 22 belonging to the second group is a wiring or pipe having a smaller bending radius than the wire 21 belonging to the first group.

It is a figure explaining a 1st prior art example, (a) represents the mode of the folding of the circumferential direction in a plane, (b) represents the mode of the folding in a cylindrical surface. It is a figure explaining the 2nd prior art example. It is a figure explaining a 3rd prior art example. The principal part structure of the wiring and piping apparatus which concerns on embodiment of this invention is represented with sectional drawing along an axis | shaft. It is the figure which looked at the mode of wiring and piping using the double pipe in the wiring and piping apparatus shown in FIG. 4 from the axial direction. The state of the striate body in the wiring and piping in the embodiment of the present invention is shown for (a) when rotating clockwise, (b) when neutral (rotating zero), and (C) when rotating counterclockwise. It is sectional drawing explaining the example using the color of a low friction coefficient. It is a figure explaining the example of the holding method of wiring and piping, (a) represents a mode that it fixed with the binding band, (b) represents a mode fixed with the fixing member. It is a figure explaining the example at the time of using a holding member among the holding methods of wiring and piping.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Fixed side housing 3 Moving side housing 4 Bearing 11 Inner pipe material 12 Outer pipe material 13 Connection member 14 Color 21 Wiring and piping (inner striatum = first group)
22 inner striatum (outer striatum = second group)
23, 24 Holding part 25 Mounting part 26 Wiring / Piping (first group / second group)
27 Binding Band 28 Fixed Member 29 Holding Member A Outer Member B Inner Member C Fixed Side Fixed Part D Movable Side Fixed Part

Claims (5)

Between the first member and the second member that rotate relative to each other around a predetermined axis, at least one of wiring and piping is included, and one end is held by the first member and the other end is held by the second member. A wiring / pipe processing apparatus for attaching a plurality of wire bodies,
A pipe member having a double structure in which a part of the inner pipe member and the outer pipe member having different diameters are connected via a connecting member so that the inner and outer pipe members are fixed in a substantially concentric relative positional relationship; Attaching to the first member so that the central axis of the pipe member having a heavy structure and the central axis of the relative rotation substantially coincide with each other,
Dividing the plurality of striated bodies into a first group and a second group, passing the striated bodies belonging to the first group through the hollow portion of the inner pipe member, and striating the striated bodies belonging to the second group Arranged to pass through the gap between the inner pipe material and the outer pipe material , and
When the first member is in a predetermined relative rotational position with respect to the second member, the striatum belonging to the second group is not wound around the inner pipe material,
When the first member is in a position rotated rightward from the predetermined relative rotation position when viewed from the second member side, the first member is wound clockwise along the outer side of the inner pipe member, and from the predetermined relative rotation position. A wiring / pipe processing apparatus adapted to be wound in a left-handed manner along the outer surface of the inner pipe member when in a left-turned position . The umbilical member belonging to the second group, the Ru smaller wires and pipes der bend radii than the first umbilical member belonging to the group, the wiring and piping processing apparatus according to claim 1. Striatum contacts, inner and outer surfaces of said inner pipe member, and the surface treatment for wear protection in at least a portion of the inner surface of the outer pipe member is that they are applied, according to claim 1 or claim The wiring / pipe processing apparatus according to 2. A collar made of a low-friction material is inserted along at least part of the inner and outer surfaces of the inner pipe material and the inner surface of the outer pipe material with which the striate body contacts. The wiring / pipe processing apparatus according to claim 1. It said first member and said second member, Ru member der constituting a part of the robot machine body, of the claims 1 to 3, the wiring and piping processing apparatus according to any one.

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