JPH1034587A - Industrial robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a cable from coming in contact with and winding around a rotating shaft by providing the rotating shaft of one driving device with the other driving device in a plurality of driving devices for driving a plurality of rotating members, and providing a support member for supporting a cable extended between these driving devices, rotatably at the rotating shaft. SOLUTION: One driving device 39 is composed of a motor fixing flange, a turning shaft motor 15, a reduction gear 17 and a turning shaft 18, and the other driving device 40 is composed of a rotating flange 21, a turning transmission member 22, and the like. A cable 47 to the driving device 40 is fixed to a cable clamp 48 provided at the lower face of the rotating flange 21, and then wound by one turn around the outside of a sleeve 45 and fixed to a cable clamp 49 provided at the upper face of a floating flange 42. The cable 47 is then passed on the outside of the floating flange 42 and fixed to a cable clamp 50 slightly shifted in position from the cable clamp 49 at the lower face of the floating flange 42, and then wound by one turn around the outside of the sleeve 44 and fixed to a cable clamp 51 provided at the upper face of a base part 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an industrial robot having a mechanism in which one driving device is rotated by another driving device.

[0002]

2. Description of the Related Art An industrial robot has a plurality of rotating members and a plurality of driving devices for driving the rotating members. One driving device is provided with another driving device on a rotating shaft. There is a device having a mechanism for rotating the other driving device by rotation of a rotating shaft driven by the one driving device. In such an industrial robot, for example, when a cable for driving the other drive device is extended to the one drive device side, an extra length is provided to allow relative rotation of these cables, and the extra length portion is provided. Is wound around the rotating shaft.

[0003]

When it is necessary to increase the rotation angle of the other driving device with respect to the one driving device, the cable must have a longer length, and interference with other members is required. To avoid this, the winding angle (number of turns) of the cable around the rotation axis must be increased. However, when the winding angle of the cable around the rotation axis is increased as described above, when the other driving device 101 is rotated with respect to the one driving device 100 as shown in FIG. The cable 102 may be worn by contact with the shaft 103, or the cable 102 may be wound around the rotating shaft 103 and an abnormal tensile force may be applied to the cable 102 to cause breakage.

[0004] Therefore, an object of the present invention is to prevent the possibility of the cable breaking or the like by preventing the cable from contacting or winding around the rotating shaft even when the winding angle of the cable around the rotating shaft is large. An object of the present invention is to provide an industrial robot which can be manufactured at a low cost and can improve reliability.

[0005]

In order to achieve the above object, an industrial robot according to a first aspect of the present invention includes a plurality of rotating members and a plurality of driving devices for driving the rotating members. And providing another driving device on a rotating shaft of one driving device, and rotating the other driving device by rotation of the rotating shaft by driving the one driving device, wherein the one driving device A support member for supporting a cable extending between the device side and the other drive device side is rotatably provided on the rotating shaft. Thereby, since the support member supports the intermediate portion between the one drive device side and the other drive device side of the cable, the cable length between the support positions can be shortened, and the distance between the support positions can be reduced. The winding angle of the cable can be reduced and the winding shape can be stabilized. Therefore, even if the winding angle of the cable around the rotating shaft is increased, contact or winding between the cable and the rotating shaft can be prevented.

An industrial robot according to a second aspect of the present invention relates to the industrial robot according to the first aspect, wherein the support member abuts on a part of the one drive unit side so as to contact the one drive unit. It is characterized in that a restricting portion for restricting the rotation angle range and restricting the rotation angle range with respect to the other drive device by contacting a part of the other drive device side is provided. Accordingly, the rotation angle range of the support member with respect to each drive device is regulated, so that contact or winding between the cable and the rotation shaft can be more reliably prevented.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an industrial robot according to the present invention will be described below with reference to FIGS. FIG. 1 shows the entire configuration of an industrial robot 11. The industrial robot 11 has a substantially disk-shaped installation flange 12 for installation and fixing.
A substantially cylindrical base 13 having a closed lower end is fixed at its upper end, and a disc-shaped motor fixing flange 14 is fixed to a lower portion inside the base 13. A rotating shaft motor 15 is attached to the lower side of the motor fixing flange 14 with its rotating shaft 16 protruding upward. The rotating shaft 16 of the rotating shaft motor 15 is mounted above the motor fixing flange 14. It is connected to the mounted speed reducer 17. The speed reducer 17 appropriately reduces the rotation of the rotation shaft 16 of the rotation shaft motor 15 and outputs the rotation to a rotation shaft (rotation shaft) 18 extending upward. A base 19 is fixed to the motor fixing flange 14 so as to cover the speed reducer 17, and the turning shaft 18 extends upward through the base 19.

A disc-shaped rotary flange 21 is coaxially fixed to the upper end of the rotary shaft 18, and a cylindrical rotary transmission member 22 is fixed above the rotary flange 21. Further, a disc-shaped motor fixing flange 23 is fixed above the turning transmission member 22. A substantially cylindrical connecting member 24 is fixed to the upper side of the motor fixing flange 23, and a substantially cylindrical hollow shaft 25 is fixed to the upper side of the connecting member 24. The pulley 26 is fixed.

Below the motor fixing flange 23,
A linear motion shaft motor 28 is mounted with its rotary shaft 29 protruding upward.
Eight rotary shafts 29 are connected to a speed reducer 30 mounted above the motor fixing flange 23. The reduction gear 30 appropriately reduces the rotation of the rotation shaft 29 of the linear motion shaft motor 28 and outputs the rotation to the drive shaft 31 extending upward.

The drive shaft 31 passes through the inside of the hollow shaft 25, and one end of a horizontally extending first arm (rotating member) 33 is fixed to the upper end thereof. At the other end of the first arm 33, one end of a second arm (rotating member) 34 extending horizontally is rotatably supported.
A wrist (rotating member) 35 is rotatably supported at the other end of the wrist. Here, the turning shaft motor 15 is
7, the rotation shaft 18 is rotated, the rotation flange 21 fixed to the rotation shaft 18 and the motor fixing flange 23 are rotated via the rotation transmission member 22, and the connecting member fixed to the motor fixing flange 23. The pulley 26 in the first arm 33 is rotated via the hollow shaft 24 and the hollow shaft 25.

The linear motion shaft motor 28 rotates the drive shaft 31 via the speed reducer 30 and rotates the first arm 33 fixed to the drive shaft 31. And, the rotating shaft motor 1
5 and the linear motion shaft motor 28 are simultaneously driven. As a result, the rotation angle of the first arm 33 with respect to the installation flange 12 is determined by the rotation angle of the rotation shaft motor 15 with respect to the motor fixing flange 14 (the rotation shaft rotation angle). )
The angle is obtained by adding the rotation angle (linear operation axis rotation angle) of the drive shaft 31 with respect to the motor fixing flange 14 by the linear operation shaft motor 28. Further, the angle difference between the rotation angle of the pulley 26 and the rotation axis, that is, the rotation angle of the linear motion axis, is determined by the transmission mechanism 36 in the first arm 33 and the transmission mechanism 37 in the second arm 34.
Through this, the central axis of the wrist 35 is linearly moved in the direction of the pivot 18, and the direction of the wrist 35 is always kept in the direction of the pivot, that is, the linear motion direction. Thus, the linear motion is performed in a state where the wrist 35 faces in a certain direction.

Here, the motor fixing flange 14, the turning shaft motor 15, the speed reducer 17, and the turning shaft 18 constitute one driving device (one driving device) 39, and the rotating flange 21 and the turning transmission member. The motor 22, the motor fixing flange 23, the linear motion shaft motor 28, the speed reducer 30 and the drive shaft 31 constitute one drive device (other drive device) 40. Then, the driving device 40 is rotated by the driving device 39.

As shown in FIGS. 2 and 3, in this embodiment, a disc-shaped rotating shaft 18 between a base 19 and a rotating flange 21 is provided in a state where movement in the axial direction is restricted. A floating flange (support member) 42 is provided rotatably with its central axis aligned. This floating flange 42
Is entirely covered with a low friction member such as a Teflon sheet (not shown). Further, the floating flange 42 and the base 19
, A sleeve 44 made of a low friction member such as Teflon is provided rotatably with the turning shaft 18 inside, and also between the floating flange 42 and the rotating flange 21.
A sleeve 45 made of a low-friction member such as Teflon is provided rotatably with the pivot 18 inside.

The drive unit 40 is provided with a single cable 47 which bundles a power supply line to the linear operation shaft motor 28 and a signal line of an encoder built in the linear operation shaft motor. Is a rotating flange 2
After being fixed to the cable clamp 48 fixed to the lower surface of the floating flange 42, it is fixed to the cable clamp 49 fixed to the upper surface of the floating flange 42 by wrapping the outside of the sleeve 45 once (or of course, plural times). Then, after passing through the outside of the floating flange 42 in the radial direction, it is fixed to the cable clamp 50 fixed to the lower surface of the floating flange 42 and below the cable clamp 49 while being slightly displaced therefrom. And then sleeve 4
The outer side of 4 is wound one turn (or a plurality of turns is also possible) in the same direction as above, and is fixed to a cable clamp 51 fixed to the upper surface of the base 19. Thus, the cable 4
7 extends from the drive device 40 side to the drive device 39 side.

Here, when the rotation angle of the floating flange 42 with respect to the rotating flange 21 is, for example, 200 degrees, when the relative angle of the floating flange 42 with respect to the rotating flange 21 is the maximum, the cable 47 is connected to the rotating shaft 18, that is, the sleeve. The cable 47 is wound most around the 45 side, and the winding angle of the cable 47 at that time is set to about 1.5 turns. In this way, when the relative angle is minimum (0 degree), the winding angle of the cable 47 is -20 degrees for one rotation. The extra length L required for the cable 47 is L = (D + d) × π × 2, where D is the outer diameter of the sleeve 45 and d is the outer diameter of the cable 47.
For example, if 1/2 of the extra length is made sufficiently smaller than the radius of the floating flange 42, the cable 47 hardly slides on the sleeve 45 and the floating flange 42, and 47 can be eliminated.

When the rotational operation angle of the floating flange 42 with respect to the base 19 is set to 200 degrees, the cable 47 from the floating flange 42 to the base 19 may be routed in the same manner as described above. Then, a rotational operation angle of 400 degrees can be obtained by combining these.

According to the industrial robot 11 having the above-described structure, the floating flange 42 supports the intermediate portion between the drive device 39 and the drive device 40 of the cable 47. Each can be shortened. That is, the cable 47 is divided between the cable clamp 48 of the rotating flange 21 and the cable clamp 49 of the floating flange 42 and between the cable clamp 50 of the floating flange 42 and the cable clamp 51 of the pedestal 19, so that the cable 47 between the supporting positions is provided. Is shortened. Thereby, the winding angle of the cable 47 between the support positions can be reduced and the winding shape can be stabilized. Therefore, contact or winding between these cables 47 and the sleeves 44 and 45 can be prevented. Therefore, the possibility of disconnection or the like of the cable 47 can be reduced, and the reliability can be improved. Therefore, the rotation angle of the driving device 40 with respect to the driving device 39 can be increased to 400 degrees as described above. Yes (conventionally less than 330 degrees)

It should be noted that the floating flange 42 can prevent the cable 47 from contacting or wrapping around the rotating shaft 18 without providing the sleeves 44 and 45 on the rotating shaft 18, thereby exhibiting a good effect. However, even if the cable 47 may slide on the turning shaft 18 side by providing the sleeves 44 and 45, the cable 47 slides on the Teflon surface of the sleeve 44 and 45 having a small friction coefficient. The resistance is kept low, so that the possibility of disconnection or the like of the cable 47 is further reduced, and the reliability is further improved.

Further, since the Teflon sheet is also attached to the floating flange 42, even if the cable 47 slides on the floating flange 42, the cable 47 will slide on the Teflon surface having a small friction coefficient. The resistance is kept low, and from this point, the cable 4
7, the possibility of disconnection or the like is further reduced, and the reliability is further improved. Here, since the base 19 is fixed to the installation flange 12 via the motor fixing flange 14 and the base 13, the portion of the cable 47 extending from the cable clamp 51 of the base 19 to the base 13 and the base 13 are separately provided. No excessive force is applied to the part extending to the installed control panel.

By the way, as described above, the rotational operation angle of the floating flange 42 with respect to the base 19 is 200 degrees, and the rotational operation angle of the floating flange 42 with respect to the rotational flange 21 is 200 degrees. When the rotation operation angle is given to the driving device 40 with respect to the driving device 39,
It is preferable to restrict the rotation of each of them beyond 200 degrees. The structure of the mechanical stopper for this purpose will be described below.

As shown in FIGS. 4 and 5, below the floating flange 42, one end is rotatably supported on a pivot shaft via a bearing 53, and the other end extends radially outward of the floating flange 42. An existing floating arm (regulator) 54 is provided. The floating flange 42 is fixed to the floating arm 54 and integrated therewith. On the upper surface of the motor fixing flange 14, two column members 56 and 57 are provided.
Are fixed to extend vertically upward. The upper portions of the column members 56 and 57 are located below the floating flange 42 so as not to interfere with the floating flange 42 and
4 and the floating flange 42
Are arranged at a position inside the outer end in the radial direction of.

The floating arms 54 of these column members 56 and 57
As shown in FIG. 6, impact absorbing members 58 and 59 for absorbing the impact at the time of collision are attached to the contact surfaces of the floating arm 54 and the column members 56 and 57, respectively. This reduces the maximum acceleration that occurs during a collision,
The column members 56 and 57 are prevented from being damaged (only the column member 56 side is shown in FIG. 6). Here, the positions of the column members 56 and 57 are arranged so as to limit the relative rotation angle of the floating arm 54 with respect to the motor fixing flange 14 to 200 degrees.

As shown in FIGS. 4 and 5, on the lower surface of the rotating flange 21, two column members 61 and 62 are fixed so as to extend vertically downward. These pillar members 6
The lower ends of the floating arms 54 can be in contact with the floating arm 54, and are located outside the radial outer end of the floating flange 54 so as not to interfere with the floating flange 54. As shown in FIG. 6, the contact surfaces of the column members 61 and 62 with the floating arm 54 and the contact surfaces of the floating arm 54 with the column members 61 and 62 absorb the impact at the time of collision. The sheet-like impact absorbing members 63 and 64 are attached, thereby reducing the maximum acceleration generated at the time of collision and preventing the column members 61 and 62 from being damaged (only the column member 61 side is shown in FIG. 6). ). Here, the positions of the column members 61 and 62 are arranged so as to limit the relative rotation angle of the floating arm 54 to 200 degrees.

Next, the floating arm 54 fixed to the floating flange 42, the column members 56, 57 and the column members 61, 62
Will be described. In addition, the rotation direction used below uses the direction in FIG. 7 for convenience. First, as shown in FIG. 7A, the column members 56 and 61
The position at which the floating arm 54 is sandwiched between and is defined as the operation start position of the motor fixing flange 14, the rotating flange 21, and the floating arm 54. In this state, the rotation of the floating arm 54 in the clockwise direction is restricted by the column member 56 fixed to the motor fixing flange 14, and therefore, the rotation of the floating arm 54 with the column member 61 abutting against the floating arm 54. Flange 21
Are in a state where they cannot rotate clockwise with respect to the motor fixing flange 14.

In this state, when the rotating shaft motor 15 is driven so that the rotating flange 21 rotates counterclockwise, as shown in FIG. 7B, no force is applied to the floating arm 54, and The rotating flange 21 rotates counterclockwise to an intermediate position where the column member 62 contacts the floating arm 54. The motor fixing flange 14 of the rotating flange 21 in the rotation from the operation start position to the operation intermediate position
And the rotation angle with respect to the floating flange 42 is 200 degrees.

Due to the rotation from the operation start position to the operation intermediate position, the cable 47 is moved so that the portion between the rotating flange 21 and the floating flange 42
Is wound around the sleeve 45 by the rotation angle of 200 degrees, that is, when the relative angle of the floating flange 42 with respect to the rotating flange 21 described above is the maximum. In addition,
During this rotation, the portion of the cable 47 between the base 19 and the floating flange 42 does not change its winding state because the floating flange 42 does not rotate with respect to the motor fixing flange 14, that is, the base 19.

Then, from the intermediate position, the rotating shaft motor 1 is rotated so that the rotating flange 21 further rotates counterclockwise.
7C, the floating flange 21 pushes the floating arm 54 with the column member 62 and the floating arm 54 comes into contact with the column member 57 integrally with the floating arm 54, that is, the floating flange 42, as shown in FIG. 7C. 7D, the column members 57 and 62 are rotated as shown in FIG.
Further rotation is restricted by the column member 57 in a state of being sandwiched between the first and second members. The positions of the motor fixing flange 14, the rotating flange 21 and the floating arm 54 at this time are the operation end positions. The rotation angle of the rotating flange 21 and the floating flange 42 with respect to the motor fixing flange 14 in the rotation from the operation intermediate position to the operation end position is 200 degrees,
The rotation angle of the rotating flange 21 is 400 degrees including the above.

By the rotation from the intermediate operation position to the operation end position, the cable 47 causes the portion between the base 19 and the floating flange 42 to move to the sleeve 44 by the rotation angle of the floating flange 42, that is, 200 degrees. The floating flange 42 is wound around and is in a state when the relative angle of the floating flange 42 to the base 19 is maximum. During this rotation, the winding state of the portion of the cable 47 between the rotating flange 21 and the floating flange 42 does not change because the floating flange 42 does not rotate with respect to the rotating flange 21.

As described above, the motor fixing flange 1
4, ie, the rotational operation angle of the floating flange 42 with respect to the driving device 39 is 200 degrees, and the rotational operation angle of the floating flange 42 with respect to the
The rotation angle is set to 00 degrees, and a rotation operation angle of 400 degrees is added to the driving device 40 in combination with the rotation angle to restrict the further rotation.

As described above, the rotation angle range of the floating flange 42 with respect to each of the driving devices 39 and 40 is regulated, so that the contact or winding between the cable 47 and the sleeves 44 and 45 can be more reliably prevented. . Therefore, the possibility of disconnection or the like of the cable 47 is further reduced, and the reliability is dramatically improved.

Therefore, even if the rotation angle of the driving device 40 with respect to the driving device 39 is increased to 400 degrees as described above, the contact or winding between the cable 47 and the sleeves 44 and 45 can be more reliably prevented. . Of course, by mechanically regulating the rotation angle of the driving device 40 with respect to the driving device 39 as described above,
It is possible to prevent runaway due to erroneous operation and the like, which is preferable also from the viewpoint of safety.

In the above embodiment, the two column members 56 and 57 are provided on the motor fixing flange 14 and the two column members 61 and 62 are provided on the rotating flange 21, respectively. As shown in FIG. 5, the floating arm 54 has two arm portions 54a, 54b extending in substantially opposite directions from the turning shaft 18, and the positions of the column members 56, 57 are shifted in the radial direction of the floating flange 42, The movement of the floating arm 54 in the clockwise direction in FIG. 8 is restricted by one arm portion 54a of the floating arm 54, and the other arm portion 54b does not interfere with the
7 so that the movement in the counterclockwise direction is regulated,
The rotating flange 21 side needs only one of the column members 61.

As a shock absorbing member of the floating arm 54, besides sticking a sheet-like member on the contact surface as described above, an O-ring 66 may be wound as shown in FIG. As described above, the through hole 67 may be formed in the floating arm 54, and the impact absorbing member 68 may be fitted into the through hole 67 with both ends protruding from the floating arm 54. Of course,
These configurations can also be applied to the column members 56, 57, 61, 62. Further, in the above description, the case where the number of the cables 47 is one is described as an example.
The present invention can be applied to a plurality of cables by appropriately increasing the number of cables 51 or using a cable capable of holding a plurality of cables.

[0034]

As described in detail above, claim 1 of the present invention
According to the industrial robot described, the support member supports the intermediate portion between one drive device side of the cable and the other drive device side, so that the cable length between the support positions can be reduced, The winding angle of the cable between the supporting positions can be reduced to stabilize the winding shape. Therefore,
Even if the winding angle of the cable around the rotating shaft is increased, contact or winding between the cable and the rotating shaft can be prevented. Therefore, the possibility of disconnection or the like of the cable can be reduced, and the reliability can be improved. Therefore, the rotation angle of the other drive device with respect to the one drive device can be increased.

According to the industrial robot according to the second aspect of the present invention, since the rotation angle range of the support member with respect to each drive device is regulated, the contact or winding between the cable and the rotating shaft is more reliably prevented. can do. Therefore, it is possible to further reduce the possibility of disconnection or the like of the cable, and to significantly improve the reliability. it can.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing one embodiment of an industrial robot of the present invention.

FIG. 2 is a side sectional view showing a main part of one embodiment of the industrial robot of the present invention, showing a cable routing structure.

FIG. 3 is a plan view showing a main part of one embodiment of the industrial robot of the present invention, showing a cable routing structure.

FIG. 4 is a side sectional view showing a main part of one embodiment of the industrial robot according to the present invention, showing a structure for restricting a rotation range.

FIG. 5 is a plan view showing a main part of an industrial robot according to one embodiment of the present invention, showing a structure for regulating a rotation range.

FIG. 6 is a side sectional view showing a main part of one embodiment of the industrial robot of the present invention, showing a structure for absorbing shock.

FIG. 7 is a plan view schematically showing a main part of an industrial robot according to one embodiment of the present invention, showing each state of rotation range regulation.

FIG. 8 is a side sectional view showing a main part of an industrial robot according to one embodiment of the present invention, showing another example of a structure for regulating a rotation range.

9A and 9B show another example of the shock absorbing member of the industrial robot according to one embodiment of the present invention, wherein FIG. 9A is a side view and FIG. 9B is a front view.

FIG. 10 shows still another example of the shock absorbing member of the industrial robot according to one embodiment of the present invention,
(A) is a side view, (b) is a front view.

FIG. 11 is a side sectional view showing a main part of one embodiment of a conventional industrial robot.

[Explanation of symbols]

 18 Revolving shaft (rotating shaft) 33 First arm (rotating member) 34 Second arm (rotating member) 35 Wrist (rotating member) 39 Driving device (one driving device) 40 Driving device (other driving device) ) 42 Floating flange 47 Cable 54 Floating arm (Regulator)

Claims (2)

[Claims] A plurality of driving members for driving the rotating members; a driving device provided on a rotating shaft of one of the driving devices; An industrial robot that rotates the other drive device by rotation of the drive device, wherein a support member that supports a cable extending between the one drive device side and the other drive device side includes the rotation shaft. An industrial robot characterized by being rotatably mounted on a robot. 2. The support member abuts on a part of the one drive device side to limit a rotation angle range with respect to the one drive device and abuts on a part of the other drive device side. 2. The industrial robot according to claim 1, further comprising a restricting portion for restricting a rotation angle range with respect to the other driving device.