JP4236999B2 - Industrial robot - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an industrial robot, and more particularly to an installation structure of a wiring cable in a wrist mechanism and an arm of an industrial robot.
[0002]
[Prior art]
As a conventional industrial robot wrist drive structure, a drive motor is disposed behind an arm that supports the wrist, and the wrist is driven via a hollow speed reducer and a hollow drive shaft provided in the arm and the wrist. (For example, refer to Patent Document 1). In this structure, a plurality of hollow speed reducers and hollow drive shafts are combined to drive several shafts of the wrist, the drive system in the wrist is complicated, and the number of parts is large.
Further, since the wiring and piping for the end effector at the tip of the wrist are inserted from the rear of the arm and led to the tip of the wrist through the inside of the arm and the wrist, the path becomes long according to the shape of the arm and the wrist.
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-113490
Similarly, another structure in which wiring and piping for an end effector are installed through the inside of an arm and a wrist is also known (see, for example, Patent Document 2).
In this structure, only the tip of the wrist is a hollow drive system, and a space region is provided in front of the drive system. After the wiring and piping are passed through the inside of the arm and a part of the wrist, the wiring and the piping are once taken out from the wrist to this space region, and are again connected to the end effector through the hollow portion of the most advanced drive system. This conventional example has a simpler structure than the combination of the hollow reducer and the drive shaft described above, but it must provide wiring and piping paths separately from the drive system, except for the most advanced wrist part. In addition, the route becomes longer.
[Patent Document 2]
JP 2002-283275 A [0004]
[Problems to be solved by the invention]
An object of the present invention is to provide an industrial robot that has a simple structure, can shorten the path of wiring and piping for an end effector as much as possible, and can easily maintain and inspect these wiring and piping.
[0005]
[Means for Solving the Problems]
The industrial robot of the present invention has a wrist mechanism having three axis units, and a robot arm that supports the wrist mechanism. The industrial robot, each axis unit of the wrist mechanism, to drive reduction gear hybrid motor incorporating together a reduction mechanism, a speed reducer hybrid motor of the first shaft unit of the robot arm, the first shaft A reduction gear integrated motor of a third axis unit arranged perpendicular to the axis of the reduction gear integrated motor of the second axis unit disposed perpendicular to the axis of the reduction gear integrated motor of the unit ; A hollow path is provided on each axis, and wiring and piping for an end effector to be attached to the tip of the wrist are bypassed through the second axis unit and passed through the hollow path.
According to this configuration, since the wiring and piping are routed directly from the first axis unit to the third axis unit and the end effector , bypassing the second axis unit, the wiring and piping can be installed at the shortest distance. Wiring and piping can be easily maintained and inspected. In addition, since a reduction gear integrated motor is used for the drive system of each axis unit, it is not necessary to provide other intermediate transmission means and the like, the wrist mechanism and the arm structure are simplified and compact, and the operation reliability is high. Wiring / piping hollow paths can be provided through these integrated motors, eliminating the need for an extra structure for wiring / piping , and minimizing the effects of rotation of each axis unit. .
[0006]
It is preferable that the robot arm has a path through which the wiring and piping are passed in the arm, and an opening for introducing the wiring and piping on a side surface of the arm.
By doing so, it is possible to minimize the wiring and piping of the arm portion as compared with the structure in which wiring and piping are passed from the rear portion of the arm. Furthermore, it becomes possible to house devices that relay wiring and piping and peripheral devices for end effectors inside the arm.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIG.
In FIGS. 1a and b, the industrial robot has an arm 8 and a wrist mechanism 10 attached to the arm. The wrist mechanism 10 includes three movable parts of a first shaft unit 11, a second shaft unit 12, and a third shaft unit 13 from the arm 8 side toward the hand. FIG. 1 shows an example in which the wiring / piping 1 is introduced from the side of the arm and guided to the end effector attached to the tip of the wrist through the axis of the first axis unit 11 and the third axis unit 13 of the wrist mechanism. is there.
[0008]
The first to third shaft units 11, 12, and 13 of the wrist mechanism 10 have speed reducer integrated motors 7, 4, and 2 each integrally incorporating a speed reduction mechanism, and are connected via brackets 6, 5, and 3. It is connected.
On the other hand, the arm 8 has an opening on the side surface, and the end effector wiring / pipe 1 pulled up from the base side of the robot is guided into the arm through the opening. A path through which the wiring / piping 1 is passed is provided in the arm 8 along the longitudinal axis of the arm. A motor 7 of the first shaft unit 11 of the wrist mechanism is attached to the tip of this arm.
[0009]
In the motor 7, the fixed side portion of the motor is bolted to the tip of the arm so that the rotation axis is aligned with the longitudinal axis of the arm 8. Further, the motor 7 has a reduction mechanism output shaft bolted to one end of the bracket 5 in the bracket 6.
The speed reducer-integrated motor 4 of the second shaft unit 12 has an orientation in which the rotation axis is orthogonal to the rotation axis of the motor 7 of the first shaft unit, and the fixed side portion of the motor 4 is bolted to the other end of the bracket 5. Yes. The bracket 5 is substantially L-shaped, and the motor 4 attached to the other end of the bracket is arranged offset from the rotation axis of the motor 7 of the first shaft unit as seen in FIG.
[0010]
Further, the motor 4 of the second shaft unit has its speed reduction mechanism output shaft bolted to the bracket 3. The other end of the bracket 3 is bolted to the fixed side portion of the speed reducer integrated motor 2 of the third shaft unit 13. The motor 2 is arranged so that the rotation axis is orthogonal to the rotation axis of the motor 4. The output shaft of the speed reduction mechanism of the motor 2 faces the hand, and an end effector is attached here.
[0011]
The motor 7 of the first axis unit and the motor 2 of the third axis unit are provided with through holes on their axes. The bracket 5 is also provided with a through hole in accordance with the through hole of the motor 7. The through hole of the motor 7 and the through hole of the bracket 5 are connected to each other to form a hollow path 20 through which the end effector wiring / piping 1 is passed.
The wiring / piping 1 passing through the motor 7 and the bracket 5 then passes through the hollow path 21 formed by the through hole of the motor 2 of the third axis unit without passing through the second axis unit 12. Thus, the end effector wiring / piping 1 passes through the arm 8, the first shaft unit 11, and the third shaft unit 13 and is guided linearly to the hand at the shortest distance.
[0012]
Here, with reference to FIG. 2, the structural example of the reduction gear integrated motor used for this invention is demonstrated. The example shown in FIG. 2 includes a motor unit 61, a harmonic drive speed reduction mechanism 62, and a cylindrical case 68 with a flange.
The motor unit 61 has the same configuration as that of a conventional AC motor, and is disposed in a case 68 serving as a stationary or stationary side portion of the motor together with a speed reduction mechanism 62 arranged coaxially with the motor unit.
[0013]
The speed reduction mechanism 62 includes a wave generator 64 connected to the output shaft of the motor unit 61, an output shaft 69 that is rotatably supported by a bearing 63 adjacent thereto, and a circular spline 65 formed on the inner peripheral wall of the case 68. The output shaft 69 has a flex spline 66 that enters between the wave generator 64 and the circular spline 65, and is driven by the motor unit 61 through these meshing.
[0014]
The through hole 60 of the motor is formed on the rotation axis through the case 68, the rotation shaft of the motor unit 61 and the wave generator 64. A sleeve 67 is provided in the through hole 60. The sleeve 67 has one end fixed to the output shaft 69 of the speed reduction mechanism, and rotates at a low speed together with the output shaft 69.
During the operation of the robot, the motors 2 and 7 rotate in the wrist mechanism 10 of FIG. 1, but the end effector piping / wiring 1 is covered with the sleeve 67 and is protected from rubbing associated with the rotation. .
[0015]
As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited only to these specific forms, A various change can be added to embodiment mentioned above, or it can be set as another embodiment.
As an example, the speed reducer-integrated motor may use other speed reducing means such as an RV speed reducer, a cyclo speed reducer, or a planetary gear speed reducer instead of the above-described harmonic drive speed reducer. Further, the end effector wiring / piping 1 may be configured to be relayed within the arm 8. In the arm 8, peripheral devices for an end effector such as a valve may be mounted as necessary.
[0016]
【The invention's effect】
The present invention uses a reduction gear integrated motor for shaft drive of the wrist mechanism, and the structure of the drive system and the rotary shaft is simple and compact. In addition, since the path of the end effector wiring / pipe is provided through these motors, the wiring / pipe can be installed without requiring an extra structure. In addition, these wires and pipes can be installed in a straight line at the shortest distance, ensuring the end effector operation and easy maintenance and inspection. By adopting such a configuration, the present invention is advantageous in that it is possible to provide an inexpensive industrial robot that is small, highly versatile, and reliable in operation.
[Brief description of the drawings]
FIG. 1 shows a main part of an industrial robot according to an embodiment of the present invention, in which (a) is a schematic top view and (b) is a side view .
FIG. 2 is a schematic sectional view showing an example of a reduction gear integrated motor used in the industrial robot of the present invention.

Claims (1)

In an industrial robot having a wrist mechanism (10) having three axis units (11, 12, 13) and a robot arm (8) for supporting the wrist mechanism, each axis unit of the wrist mechanism is provided with a speed reduction mechanism. (62) is driven by a reduction gear integrated motor (7, 4, 2) integrally incorporated, and the reduction gear integrated motor (7) of the first axis unit on the robot arm side and the reduction of the first axis unit Reducer-integrated motor of the third axis unit (2) disposed perpendicular to the axis of the reducer-integrated motor (4) of the second axis unit that is disposed perpendicularly to the axis of the motor-integrated motor The hollow path (20, 21) is provided on the axis of each, and the end effector wiring and pipe (1) attached to the tip of the wrist are routed through the hollow path, bypassing the second axis unit (11). It is characterized by Industrial robots.

Images