JP3134091B2 - Double-arm telescopic robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to the bending of a pair of arms,
The present invention relates to a dual-arm telescopic robot in which a holding portion of a work or a tool moves linearly by a telescopic operation, and in particular to a handling robot for transporting a heavy object or a processing work robot for holding a tool such as a grinding wheel and deburring a cast and forged product.

[0002]

2. Description of the Related Art Conventionally, as a robot for performing this kind of handling and processing work, a robot coordinate system in which the tip of a robot arm linearly reciprocates along a plurality of guide portions, and a plurality of shaft portions are articulated at shaft ends. The multi-joint type, which performs the required operation on the operating part attached to the tip shaft by the relative rotation and bending motion of each shaft, and other combinations of rotation and expansion and contraction of the cylindrical body and the rotation and rotation joints ahead A cylindrical coordinate type is known.

[0003]

The above-mentioned types of robots have advantages and disadvantages, respectively, and have a limited application or range. For example, the rectangular coordinate type requires a fixed guide unit and tends to be large in size, so that it is not suitable for a place where only a small space is available as an installation place. Although the multi-joint type can move the subtle motion of the shaft end, the drive motors of the respective axes cannot be controlled independently, and all motors need to be coordinated. Further, depending on the position, the problem of a singular point arises, so that the stroke is also limited. Further, the rigidity changes significantly depending on the position of each part, and the load capacity is largely fluctuated. Further, since the general cylindrical coordinate type has one arm, the rigidity around the axis of the cylindrical body, that is, the rigidity against the moment around the Z axis is low due to its structure. It is not suitable for transporting objects.

Accordingly, the present invention has high rigidity, high precision, and can have a large operating range, and can be used in a narrow space by being compactly housed in a C-shaped frame of an airframe. An object of the present invention is to provide a double-arm telescopic robot useful for edge deburring work of various structural parts.

[0005]

According to the present invention, there is provided a pair of arms provided with a bendable elbow in the middle thereof, and rotatable about a lifting and lowering and a base, and provided at the tips of the pair of arms. A pair of driven gears connected to the bases of the pair of arms, a pair of intermediate gears connecting the driven gears, and one of the pair of driven gears. A driving motor for driving, and a sprag supporting the bases of the pair of arms.
The center axes of the in- shaft portions are shifted from each other (not concentric), and the elbow portions of the pair of arms can be bent in opposite directions, and the holding device moves linearly by bending of the pair of arms. The holding device ,
Bifurcations extending inward from each other from the tips of the pair of arms
An axle pivotally supported by the arm and a tip of the pair of arms
The ends are rotatably connected to each other, and the pivot
Fixed concentrically to the lower end of the
There is provided a dual-arm telescopic robot having a mounting flange portion for holding a tool , wherein both arms are in a parallel state when the pair of arms are in a maximum extension state.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a top view of a double-arm telescopic robot according to an embodiment of the present invention, and FIG. 2 is a side view of the robot shown in FIG. 3 is an enlarged side sectional view taken along the line AA of FIG. 1, and FIG. 4 is an enlarged side sectional view taken along the line BB of FIG. Referring to these figures, a C-shaped frame (C
Upper and lower end plates 2 and 3 are rotatably supported on upper and lower portions of the frame 1 via short shafts 4 and 5, respectively. In the lower part of the C-shaped frame 1, a motor 6 with a reduction gear for overall turning is provided.
The output shaft of the motor 6 and the shaft end of the lower short shaft 5 holding the lower end plate 3 are connected via a timing belt 7. The upper and lower end plates 2 and 3 are connected by two front rotatable spline shafts 8 and 9 and one rear fixed ball screw shaft 10, so that the forward rotation of the motor 6
By the reverse rotation drive, the upper and lower end plates 2 and 3 rotate in both forward and reverse directions about the axis of the short shafts 4 and 5. A cover plate 42 is provided on the rear side of the ball screw shaft 10 to connect the two end plates 2 and 3 to each other. Needless to say, the motor 6 with a speed reducer may have a separate structure from the speed reducer and the motor.

A U-shaped elevating frame 11 is disposed between the upper and lower end plates 2 and 3. The two spline shafts 8 and 9 are inserted through the elevating frame 11. A hollow shaft 12 is spline-engaged with each of the spline shafts 8 and 9 so as to be supported between the upper and lower portions. The bases of arms 14 and 15 extending horizontally are fixed to each hollow shaft 12 at two locations with a vertical interval.

Referring to FIG. 3, the upper short shaft 4 is formed hollow, and the lower short shaft 5 is aligned with the lower short shaft 5 on the upper portion of the C-shaped frame 1 via the rolling bearing 18. It is pivoted. The upper end plate 2 is fixed to the lower end of the upper hollow short shaft 4. An arm turning motor 16 and a reducer 39 connected to the motor 16 are arranged coaxially with the short shaft 4 in the upper hollow short shaft 4. The lower surface of the speed reducer 39 is mounted and fixed on the upper surface of the upper end plate 2. The output shaft 17 of the speed reducer 39 penetrates through the upper end plate 2 and protrudes downward.
The output shaft gear 19 fixed to the speed reducer output shaft 17 has one spline shaft via an intermediate transmission gear 20 which is supported on (the back side of) the upper end plate 2 by an intermediate shaft 47 (FIG. 4). 8 meshes with the spline shaft gear 21 fixed to the shaft 8. As shown in FIG. 6, interlocking gears 22 and 23 are fixed to the upper ends of the spline shafts 8 and 9 on the upper surface side of the upper end plate 2, and these interlocking gears 22 and 23
25 are engaged with each other.

Interlocking gears 22, 23 of spline shafts 8, 9
And the number of teeth of the intermediate interlocking gears 24 and 25 are the same. Therefore, when the one spline shaft 8 rotates via the output shaft gear 19 and the spline shaft gear 21 by the driving of the arm turning motor 16, the upper end The other spline shaft 9 is opposite to the one spline shaft 8 via an interlocking gear 22 of one spline shaft 8, a pair of intermediate interlocking gears 24 and 25, and an interlocking gear 23 of the other spline shaft 9 on the plate upper surface side. Are driven in the same direction and by the same amount. Due to the rotation of the spline shafts 8, 9, the pair of arms 14, 15 spline-engaged with the spline shafts 8, 9 via the hollow shaft 12 rotate by the same amount in opposite directions.

[0010] As clearly shown in FIG.
Is mounted with an elevating motor 26. The lifting frame 11 has a ball nut 27 screwed to the ball screw shaft 10 at its rear side so as to be axially immovable and rotatable with respect to the frame 11. The output shaft of the lifting / lowering motor 26 and the ball nut 27 are connected via a timing belt 28, so that the motor 26 drives the lifting / lowering frame by the screw action of the fixed-side ball screw shaft 10 and the rotating-side ball nut 27. 11 moves up and down between the upper and lower end plates 2 and 3 together with the hollow shaft 12. In this case, the pair of spline shafts 8 and 9 penetrating the lifting frame 11 functions as a guide for the vertical movement of the lifting frame 11. The vertical movement of the lifting frame 11 causes the pair of arms 14 and 15 to move up and down via the hollow shaft 12 in a horizontal state.

A pair of air cylinder devices 30 are mounted between the upper end of the frame 11 and the lower end plate 3 at both side positions of the lifting frame 11. In the illustrated embodiment, the lower end of the cylinder body 31 is fixed to the lower end plate 3, the upper end of the cylinder body 31 is loosely inserted into the lower part of the elevating frame 11, and the tip of the cylinder rod 32 is connected to the lower surface of the upper part of the frame 11. Through a spherical seat 33 and a spherical receiver 34 at the tip of the rod,
It is in contact with the upper lower surface of the lifting frame 11. The air cylinder device 30 reinforces the operation of the elevating motor 26, thereby making it possible to reduce the capacity of the elevating motor 26, and is effective in quickly performing acceleration and deceleration during frame elevating driving. The overall turning motor 6, the arm turning motor 16, and the elevating motor 26 are each constituted by a servomotor.

Referring to FIGS. 1 and 2, a pair of arms 1
The intermediate portions of the elbows 4 and 15 each have an elbow joint structure so that they can be bent in opposite directions, that is, outwardly. Specifically, the base side arm members 14a, 15
a and the distal arm members 14b and 15b are connected by a shaft 46. In the present embodiment, the distal ends of the distal end side arm members 14b, 15b are formed with bifurcated portions 35, 36 which are vertically separated from perforated holes extending inward. As shown in FIG. 7, the forked portion 35 of one of the distal arm members 14b is provided.
Is wider than that of the other, and each fork 35, 3
The other fork 36 enters the space between the two forks 35 so that the holes 6 are aligned, and the tip spindle 37 is inserted into the hole via a rolling bearing 38 (FIG. 8). . At the lower end, a mounting flange 41 for a workpiece or a processing tool is fixed. When the robot of the present embodiment is used for deburring an edge of a cast and forged product , a grinding wheel (not shown) is attached to the flange 41.

As described above, the pair of arms 14 and 15 are moved from the extended state (solid line position) in FIG. 1 by the urging of the arm turning motor 16 held on the upper part of the C-shaped frame 1 and the spline shafts 8 and 9. When the arms are rotated outward by the same amount in opposite directions around the center, the arms 14 and 15 are connected such that the elbows 45 project outward as shown by broken lines in FIG. And the tip of the arm moves linearly toward the C-shaped frame. Arm 14,
When the arm 15 rotates in the opposite direction to the above, the elbow 45 extends straight, and the mounting flange 41 held on the main shaft 37 at the end of the arm eventually moves between the maximum extension position and the maximum bending position of the arm 14, 15 at the end. In between (R-axis stroke, FIG. 1), reciprocating horizontal movement is performed linearly.

When the lifting motor 26 mounted on the lifting frame 11 is energized, the driving force rotates the ball nut 27 on the lifting frame 11 via the timing belt 28, as described above. By the screw action with the screw shaft 10, the lifting frame 11 and the pair of arms 14, 15 held by the frame 11 move up and down using the pair of spline shafts 8, 9 as guides (Z-axis stroke,
(Fig. 2).

When the entire arm is turned in a horizontal plane, the lower arm 5 and the lower arm 5 are fixed via the timing belt 7 by the driving of the motor 6 for turning in the lower part of the C-shaped frame 1. The lower end plate 3 rotates. Lower end plate 3
Torque is transmitted to the upper end plate 2 via the cover plate 42, the pair of spline shafts 8 and 9, and the ball screw shaft 10, and the upper hollow short shaft 4 that supports the upper end plate 2 on the upper portion of the C-shaped frame 1. The upper end plate 2 also rotates integrally with the arm turning motor 16, whereby the entire arm turns together with the elevating frame 11 about the axes of the upper and lower short axes 4 and 5. Since torque transmission from the lower end plate 3 to the upper end plate 2 is mainly received by the cover plate 42, a large torque is not applied to the ball screw shaft 10 and the spline shafts 8 and 9.

In the above embodiment, a pair of spline shafts 8,
9 is driven and the gear is transmitted to the other spline shaft 9. However, each of the two spline shafts may be independently driven to rotate by a servomotor. In this case, the R axis of the arm is used. A similar arm operating range can be realized with two motors having a driving capacity of about １ ／.

[0017]

As described above, according to the present invention, since the arm has a double arm structure and the entire mechanism is supported by the C-shaped frame, high rigidity is ensured, and in particular, heavy-duty conveyance is achieved. The rigidity with respect to the horizontal load generated during acceleration / deceleration or grinder work is increased, so that the arm length and the expansion / contraction stroke can be increased accordingly, and the operating range can be expanded. In addition, each base of the double arm is supported on the lifting frame at two locations at large intervals vertically, and the lifting frame is guided by two spline shafts and one ball screw shaft. High rigidity can be obtained even with respect to a vertical load applied to the substrate. Since the turning mechanism is supported by the short axis having a large outer diameter at the upper and lower portions of the C-shaped body frame, the turning accuracy can be increased in addition to the high rigidity. As described above, the present invention has the effects of securing high rigidity while maintaining high accuracy, extending the operating range of the arm, and realizing a compact industrial robot by housing the mechanism in a C-shaped frame.

[Brief description of the drawings]

FIG. 1 is a top view of a double-arm telescopic robot according to an embodiment of the present invention.

FIG. 2 is a side view of the robot shown in FIG.

FIG. 3 is an enlarged side sectional view taken along line AA of FIG. 1;

FIG. 4 is an enlarged side sectional view taken along the line BB of FIG. 1;

FIG. 5 is a transverse sectional view taken along the line CC of FIG. 3;

FIG. 6 is a transverse sectional view taken along line DD of FIG. 3;

FIG. 7 is a front view of the holding device as viewed from the direction of arrow F in FIG. 1;

FIG. 8 is an enlarged side sectional view of the holding device shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 C-shaped frame 2 Upper end plate 3 Lower end plate 4 Upper hollow short shaft 5 Lower short shaft 6 Motor with reduction gear for whole rotation 8,9 Spline shaft 10 Ball screw shaft 11 Lifting frame 12 Hollow shaft 14,15 Arm 16 Arm rotation Motor 27 Ball nut 28 Timing belt 30 Air cylinder device 35, 36 Bifurcation 37 Tip spindle 41 Mounting flange

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B25J 17/00 B25J 9/06

Claims (2)

(57) [Claims] 1. A pair of arms provided with a bendable elbow in the middle thereof and rotatable about a vertical movement and a base, and a holding device for a work or a processing tool provided at the tips of the pair of arms. And a pair of driven gears respectively connected to the bases of the pair of arms and a pair of intermediate gears connecting the driven gears, and a drive motor for rotating one of the pair of driven gears, The spline shaft portions that support the bases of the pair of arms are offset (not concentric) from each other in the axis, and the pair of arms have the elbows that can be bent in opposite directions. The holding device is configured to move linearly, and the holding devices move inwardly from the distal ends of the pair of arms.
A pivot that is pivotally supported by a bifurcated portion that extends
Connect the ends of the pair of arms so that they can rotate relatively
And is fixed concentrically to the lower end of the pivot, and
A dual-arm telescopic robot having a mounting flange for holding a workpiece or a working tool , and wherein the two arms are in a parallel state when the pair of arms are in a maximum extended state. 2. An upper and lower end plate rotatably supported by upper and lower portions of a C-shaped body frame, a screw shaft and a pair of spline shafts connecting the upper and lower end plates, and a nut screwed to the screw shaft. An elevating frame that holds and moves up and down while being guided by the pair of spline shafts, an elevating motor mounted on the elevating frame, and operatively connected to the nut, and disposed on a fixed side of the machine body. And, a general turning motor for rotating the upper and lower end plates, and an arm turning motor arranged on the fixed side of the body and rotating the pair of spline shafts in opposite directions to each other, 2. The dual-arm telescopic robot according to claim 1, wherein each base of the pair of arms is supported by the spline shaft via the lifting frame so as to be vertically movable. 3.