JPH02303778A - Arm driving mechanism for robot - Google Patents

Abstract

PURPOSE:To prolong the life of a cable by arranging a transmission shaft at a position in separation and in parallel to a turning center axis inside a turning arm and permitting a power feeding cable to be wired in close contact with the arm and avoiding distortion. CONSTITUTION:The turning power generated by a turning driving means 12 is transmitted to a turning shaft 39, and a turning arm 5 is turned by an arbitrary angle around the center axis of the arm, by the turning power. Further, the turning power generated by a top edge arm driving means 13 is transmitted to a top edge arm 6 through a transmission shaft 42 and an output shaft 17 which are internally installed onto the turning arm, in separation and in parallel to the input shaft and the center axis of the turning arm, and the top edge arm turns by an arbitrary angle similarly. A cable 50 for supplying the power into a working member installed at the top edge by these arms can be arranged along the arm, passing through the vicinity of the center axis of the turning arm 5, and the distortion of the cable is not generated, and wiring can be carried out by closely attaching the cable onto the arm.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to an arm drive mechanism that drives a distal arm disposed at the distal end of a pivot arm that pivots around a central axis of the arm. .Relates to an arm drive mechanism for a robot that is capable of wiring a cable, etc. for feeding power to a processing tool, etc. disposed at the tip end of the arm, so as not to cause twisting due to the pivoting action of the pivoting arm.

(Prior art) Generally, due to recent advances in automation technology, in various manufacturing factories, various welding operations such as spot welding are sometimes performed automatically using L] bobbins. Conventionally, robots that perform such welding work require complicated movements, so for example,
A so-called articulated robot as shown in the figure can be used.

The robot, which is not shown in the figure, is a so-called B-axis robot that has eight rotating parts as shown by the arrows in the figure.
A horizontally pivoting body 2 is removed, and this body 2 has link arms 3, 4 which each rotate independently.
is rotatably removed. Each of these link arms 3.4 is equipped with a swing arm 5 that pivots around the central axis of the arm, and this swing arm 5 is rotated by the link arm 3.4. It can be moved backward and tilted at any angle, and the arm connected to the tip of the swing arm 5 can be freely moved. Further, the rotating arm 5 further includes a first arm 6 that rotates in an arbitrary angle with respect to the central axis of the rotating arm 5.
and a second arm 7 are connected, and the tip of the second arm 7 has a hand 8 that rotates in a direction perpendicular to the rotation direction of the second arm 7, and a hand 8 that rotates in a direction perpendicular to the rotation direction of the second arm 7. A spot welding gun (hereinafter referred to as gun) 9 which rotates in a perpendicular direction is also installed.

The body 2 is driven by a body drive motor (not shown), which is disposed on the stand 1, and link arms 2.3.
are arranged in the body 2 and are driven by respective drive motors 10 and 11. Also, the rotating arm 5,
The first arm 6 and the second arm 7 are driven by a swing motor 12 and an arm drive motor 13 provided in the swing arm 5, and roughly, the hand 8 and the gun 9 are driven by a swing motor 12 and an arm drive motor 13, respectively. Hand motor 14 and gun are driven overnight 15
It is designed to be driven by. These motors are controlled by an external control device (not shown), and by driving each arm, the gun 9 is moved to an arbitrary position relative to the object to be welded, and each part of the object to be welded is moved to the slots 1 to 1.
It can be welded.

Furthermore, in the illustrated robot, the second arm 7 responds to the movement of the first arm 6 in order to reduce the movement of the tip of the swing arm 5 and to improve the movement speed of the arm. The arms are designed to move at the same time, and the arm drive mechanism
The arm drive mechanism for driving each of the first arm 6 and the second arm 7 by the lever 13 has a groove structure as shown in FIG.

As shown in the same figure, inside the swing arm 5, a gear arm drive unit 13 is connected.
A transmission 1N 116 is provided to transmit the rotational force of J3.
The rotational force of the arm drive motor 13 can be transmitted to the output shaft 17.
The first arm 6 is connected to the input shaft 20 of the reducer 19 connected to the output shaft via the timing pulley 23 and the timing belt 24, and the rotational force of the arm drive [-13] is transmitted to this @speed reducer 19. The first arm 6 is configured to rotate according to the reduction ratio of the reduction gear 19.

Further, the output shaft 20 is connected to the input $11122 of the reducer 21 connected to the second arm 7 or the output shaft via the timing pulley 25 and timing bells 1 to 26, so that the rotation of the arm drive motor 13 is controlled. The force is also transmitted to this reduction gear 21, and the second arm 7G, t rotates in the same manner as the first arm 6 according to the reduction ratio of this reduction gear 21.

Then, when the arm drive [-13] is driven by the control device that controls the robots 1 to 1, this arm is driven and
The rotational force of No. 3 is generated by the transmission shaft 16, the paddle gear 18, and the output shaft 17.
, is transmitted to the input shaft 20 via the timing pulley 23 and the timing belt 24 to drive the first arm 6, and at the same time, from the input shaft 20 to the timing pulley 25 and the timing bell 1 via 26 to the input shaft 22. is transmitted and drives the second arm 7.

In this way, in the past, it was possible to simultaneously drive multiple arms with one arm 9, and to drive the arms without having to install a heavy motor in the arm to be driven. There is an arm drive mechanism that allows the arm to move at 13 speeds.

(Problem to be Solved by the Invention) However, even with such a conventional arm drive mechanism, for example, one motor of the motor that drives the arm attached to the tip of the swing arm cannot be connected to the back of the swing arm. This is because in order to drive all the parts of the J, the arm drive would become complicated, and there is a risk that the speed of the arm would increase. As a result, couples for supplying power to the motors that drive those arms, and couples for supplying power to processing tools such as Spora 1 to welding guns, etc., are wired along people's arms. As a result, there was a risk that these couples would be twisted due to the pivoting action of the pivot arm, and a load would be applied to them, resulting in a significant decrease in durability.

Also, if such a pull is placed too far from the arm, it may interfere with surrounding equipment, so it is desirable to cover the wiring as close to the arm as possible. In addition, the wiring must be routed with enough room to accommodate the movement of the swivel arm, making it difficult to route the wiring closely to the arm.
In some cases, there was a risk that the cables would interfere with surrounding equipment.

The present invention has been made to solve these conventional problems, and the cable that drives the arm at the tip and is connected overnight is not twisted due to the pivoting action of the pivoting arm. It is an object of the present invention to provide a arm drive mechanism for a robot that can be wired in close contact with the arm without causing any damage.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a rotating arm J, which rotates around the central axis of the arm of a robot in which a plurality of arms are connected. an arm drive mechanism that transmits a driving force to the tip arm, the support supporting the pivot arm having a hollow pivot shaft mounted on the central axis of the pivot arm and causing the pivot arm to pivot; A swing drive f stage that is rotatably attached to the member, is connected to the pivot shaft, and rotates the pivot arm, is attached to the support member, and a tip arm driving means for driving the tip arm is attached to the support member, The input shaft, which is connected to the tip arm drive means and inputs the driving force of the tip arm drive means, is rotated βJ so that it has the same center axis as the rotation center axis of the pivot shaft and independently of the pivot shaft. a transmission shaft that is attached to the rotation shaft, is connected to the input shaft, and transmits the driving force of the tip arm drive@r stage, and the center axis of the transmission shaft is spaced apart from the center axis of the rotation arm. An output shaft which is rotatably mounted inside the bending swing arm in parallel and connected to the transmission shaft C and which outputs the driving force from the four stages of drive of the end arm to the end arm is attached to the turning pull arm. It is characterized by a single digit.

(Function) The present invention configured as described above functions as follows.

The rotational force generated by the rotation drive means is transmitted to the rotation shaft, and the rotation arm responds to this rotational force by rotating at any angle around the central axis of the arm, and the rotational force generated by the four-stage tip arm drive is transmitted to the rotation shaft. The rotational force is transmitted to the tip arm via the input shaft, the transmission shaft and output shaft built into the swing arm, which are spaced apart from and parallel to the center axis of the swing arm. IsJ rotates. Cables that supply power to the processing members and drive members that are taken out from the tips of these arms can pass near the center axis of the swing arms and be routed along the no arms. In addition, it is possible to wire the wiring in close contact with the ) arm without twisting due to the pivoting movement of the pivot arm.

(Example) Below, the arm drive mechanism for the robot 1 according to the present invention will be explained in detail based on the drawings.

FIG. 1 is a schematic diagram of the arm drive mechanism of the robot according to the present invention. The arm drive mechanism is such that the cable that drives the arm at the tip and feeds power to processing tools, etc. can be wired in close contact with the arm without twisting due to the swinging action of the swinging arm. It is shown. The illustrated articulated robot is the same as the robot explained in the conventional technique, and the same members as those explained in the conventional technique are given the same reference numerals. The explanation of the members other than the pulled swing arm 5 will be omitted.

As shown in the figure 1. The rotating arm 5 rotates around the central axis of the i-arm, and is supported by a holder 30 that can move forward, backward, and tilt at any angle by means of the link arm 3.4.

This holder 30 is formed with an insertion hole 31 through which the swing arm 5 is inserted. It has become. Further, at the other end of the holder 30, a mounting hole 35 is formed for attaching a reducer 34 whose output shaft 33 is connected to the swing arm 5.
5, a reducer 34 is installed so that the axis of the output shaft 33 coincides with the central axis of the swing arm 5. The through hole 31 and the attachment hole 35 allow the swing arm 5 to be supported by the boulder 30 so as to be able to swing around the central axis.

Further, the deceleration mechanism 34 is equipped with brackets I to 36, and the bracket 36 is equipped with a swing motor 12 that drives the swing arm 5 and an arm drive motor that drives the first arm 6. 13 is installed. still,
These terminals are connected to an external control device (not shown) as in the conventional case, and are driven and controlled by this control device (42).

The output shaft of the swing motor 12 is connected to three hollow pano shafts of a reduction gear 34 via a timing pulley 37 and a timing belt 38. In other words, the turn is -91
The rotational force outputted from the drive unit 2 is increased in rotation speed by a speed reducer 34 and transmitted to the swing arm 5. 33, it is designed to rotate around the central axis of the rotating arm 5.

Further, the output shaft of the tip arm drive motor 13 is connected to the reducer 3 via a timing pulley 40 and a timing belt 41.
It is connected to one end of a transmission input shaft 42 which is inserted into the center of the input shaft 39 of No. 4 and taken out. This transmission input shaft 4
2 is inserted through the center of the hollow-shaped input@39, and is rotatably supported by a bearing 43 so as to be coaxial with the input@39, and the other end of the transmission input 1N142 (
The transmission input shaft 42 is rotatably supported via a bearing 45 by a shaft 44 mounted on the output shaft 33 of the reducer 34, and rotates independently of the input shaft 39. It is now possible.

This transmission input 1N142 transmits the rotational force of the arm drive 13 to the transmission shaft 16G: transmission drive #? A transmission driven gear 47 that meshes with this transmission drive #746 is attached to one end of the transmission shaft 16. This transmission shaft 16 is connected to an output shaft 17 disposed at the tip of the swing arm 5, as in the conventional case.
The transmission shaft 16 is a transmission shaft formed in the swing arm 5 so that the axis is spaced from and parallel to the central axis, which is the center of rotation of the swing arm 5. It is rotatably supported in the bearing hole 4B via a bearing 49, and the rotational force of the arm drive sweater 13 is transmitted from the transmission input shaft 42 by the transmission drive gear 4G and the transmission driven gear 47.

The other end of the transmission shaft 16 is provided with bevel teeth as in the past.
Since i18 is removed, the transmission @l116 can transmit the rotational force of the arm drive sweater 13 to the output shaft 17 via this bevel gear 18.

Furthermore, this output shaft 17 is connected to the man-horn shaft 20 of the reducer 19, to which the first arm 6 is connected to the output shaft, via a timing pulley 23 and a timing belt 24, as in the conventional case. , rear arm drive (13 rotations)] is transmitted to this one reduction gear, and the first arm 6 is configured to rotate according to the reduction ratio of this reduction gear 19.

In general, as described above, the swing arm 5 is equipped with a cable 50 for supplying power to the motor that drives the other arm at the distal end and the processing tools 5 disposed at the distal end of the arm.
An insertion hole 51 for passing the cable 50 into the inside of the swing arm 5 is formed at the lower part of the transmission shaft 16.
is wired along the arm from the machine and the processing tool, passing through the insertion hole 51 near the center axis of rotation inside the rotating arm 5, and being wired to the rear of the rotating arm 5 to the outside. It is designed to be connected to a control device. In other words,
By arranging the transmission @1 (3) apart from and in parallel with the rotation center axis of the rotation arm 5, the cable 50 can be routed through the vicinity of the rotation center axis of the rotation arm 5 as shown in FIG. It looks like this.

The arm drive mechanism configured in this manner drives the swing arm b and the first arm 6 as follows.

First, when the swing motor 12 is driven by an external control device, the rotational force generated in the swing motor 12 is transferred from the output shaft of the swing motor 12 to the timing pulley 3.
7 and the timing belt 38 to the input fiII 139 of the reducer 34, and the rotation speed is reduced by the reducer 34 and output to the output shaft 33, so that the rotation arm 5 connected to the output shaft 33 rotates around the axis of the output shaft 33.

Similarly, the arm drive motor 13 is controlled by an external control device.
When the arm drive motor 13 is driven, the rotational force generated by the arm drive motor 13 is transmitted from the output shaft of this motor to the timing pulley 40 and timing bell 1 via 41 to the transmission input shaft 42. The rotational force transmitted to the transmission shaft 16 is further transmitted to the transmission shaft 16 via the transmission drive gear 46 and the transmission driven gear 47. , output shaft 17, timing pulley 23, and timing belt 2
The rotational force is transmitted to the input shaft 20 of the reducer 19 via the reducer 4, and the rotational speed is reduced by the reducer 19, and the rotational force is transmitted to the first arm 6 connected to the output shaft of the reducer 19. rotates according to the reduction ratio of this reduction gear 19.

When the swing arm 5 and the 17th to 86th move in this way, the other arms at the tip 81S are driven [--in order to supply power to the processing tools disposed at the tip and the tip end.
The cables 50 that pass from the rear of the swing arm 5 to the vicinity of the center axis of the swing inside the swing arm 5 and through the insertion hole 51, and are wired to the shutters and processing tools thereof, pass near the center axis of the swing. Since the wires are wired in such a manner, twisting due to the turning operation of the turning 2-me 5 does not occur.

Therefore, the transmission 116 that transmits the rotational force to the first arm G connected to the distal end of the swing arm 5 is arranged inside the swing arm 5 so as to be spaced apart from and parallel to the swing center axis. 2, the cable 50 can be routed in the vicinity of the pivot axis of the pivot arm 5, so that even when the pivot arm 5 pivots, the cable 50 will not be twisted.

In this embodiment, an 8-axis multi-joint robot similar to the robots 1 to 1 described in the prior art section was used as an example.
The present invention is not limited to this, but it is only necessary to have a rotating arm that makes one turn about the central axis of the arm, and to drive an arm connected to the tip of the rotating arm.

(Effects of the Invention) As is clear from the above description, the present invention has the following effects.

The transmission shaft is located inside the swing arm, and the swing center Itli
By arranging position numbers spaced apart and parallel to I [J, cables that supply power to workpieces, etc. that are cut at the tips of multiple arms can be passed near the center axis of the swing arm and connected to the arm. This cable is free from twisting due to the swinging action of the swinging arm, and can be wired in close contact with the arm. J: The load on the arm does not come off, the life of the cable can be reduced with respect to the movement of the arm, and maintenance time caused by cable breakage can be saved, so productivity can be significantly improved.

In addition, since the cable passes inside the rotating arm and is routed in close contact with the arm, there is no risk of the cable interfering with surrounding containers.For example, the arm can be moved at higher speeds. Not only is it possible to
In so-called eyeing work, consideration of such interference can be reduced, and work efficiency is improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a robot arm drive mechanism according to the present invention, FIG. 2 is a view taken along the arrow in FIG. 1, and FIGS. 3 and 4 are explanatory diagrams of a conventional arm drive mechanism. 5...Swivel arm, 6...First arm (tip arm), 12...Swivel motor (swivel drive means), 13...
・Arm drive-9 (tip arm drive means), 16...
- Transmission shaft, 17... Output shaft, 30... Holder (supporting member), 39... Input shaft (swivel axis), 42... Transmission input shaft (input shaft).

Claims (1)

[Claims] An arm drive mechanism that transmits driving force to a distal end arm from a pivoting arm that pivots about the central axis of the arm, among the arms of a robot in which a plurality of arms are connected, A hollow-shaped pivot shaft attached to the pivot shaft for pivoting the pivot arm is rotatably attached to a support member that supports the pivot arm, and a pivot driving means connected to the pivot shaft for pivoting the pivot arm is supported by the pivot shaft. A distal arm driving means that is attached to a member and drives the distal arm is attached to the support member, and an input shaft that is connected to the distal arm driving means and inputs the driving force of the distal arm driving means is connected to the rotation axis of the pivot shaft. a transmission shaft that is attached to the rotation shaft so as to be coaxial with the central axis and rotatable independently of the rotation shaft, is connected to the input shaft, and transmits the driving force of the tip arm driving means; The transmission shaft is rotatably mounted inside the swing arm with the center axis of the transmission shaft spaced from and parallel to the center axis of the swing arm,
An arm drive mechanism for a robot, wherein an output shaft is connected to the transmission shaft and outputs a driving force from the tip arm driving means to the tip arm, and is attached to the swing arm.