JPH042392B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a hand structure for an assembly robot capable of performing a variety of tasks by attaching a plurality of grips to a turret-type rotating head.

(Prior art) In assembly robots, there is a device in which a plurality of hands are attached to a turret-type rotary head to enable the delivery and reception of a wide variety of workpieces with different shapes and processing details.A typical example is shown in Fig. 4. In the example shown in FIG. 4, the hand mounting portion 4' has a hexagonal cross section perpendicular to the rotation axis and has a grip shaft 6 in a direction perpendicular to the rotation axis. The hands H, H are installed in a radial manner with equal distribution, and the rotating shaft is rotated at an integral multiple of 60°, and a compressed air supply port _P1 for band opening/closing operation and a compressed air supply port P for holding the hand gripping operation are installed. By supplying compressed air through _{No. 2} , opening and closing operations related to workpiece processing can be performed at the vertically downward position, and gripping operations in preparation for transferring and receiving workpieces can be performed at other positions. In the example shown in the figure, a truncated quadrangular pyramid-shaped hand attachment part 4'' with four slopes that intersect at 45 degrees with respect to the rotation axis that is inclined at 45 degrees to the horizontal direction is attached. After fixing four hands H, H each having a grip part in a direction of 45 degrees with respect to the rotation axis on the slope, the rotation axis is rotated at a rotation angle that is an integral multiple of 90 degrees, and each hand H, It has a structure that allows the gripping and release operations of H to be performed.

In both of the above examples, the shape of the hand attachment parts 4', 4'' has a limit and cannot be made too large, and therefore each hand H cannot be attached with a heavy weight type, so it is difficult to grip small parts. There is a problem that is limited to

If the target parts to be gripped, transported, and assembled by each of the above robots are light, small parts such as electronic parts, and the assembly is not transported, a robot for small parts can be used. In some cases, the weight of the target workpiece is often large, so the robots in both of the above examples cannot handle heavy workpieces, and they cannot handle the transportation of assembled products, so they cannot handle heavy workpieces. There is a drawback that it is necessary to prepare a large hand for use.

Furthermore, when assembling parts, it is not possible to perform attitude control to arbitrarily change the rotation angle with respect to the gripping shaft, and rotation control cannot be performed when screwing, so there is the inconvenience that a variety of tasks cannot be handled.

(Object of the Invention) The present invention has been made in an attempt to eliminate the drawbacks of the conventional devices as described above. An object of the present invention is to realize a multi-purpose composite hand that can be adapted to various tasks, especially assembly tasks, by making the main hand of the hand a heavy-duty gripping type. .

(Structure of the Invention) The present invention provides a turret-type composite hand in which the main hand and the rotation drive device are horizontally and coaxially connected via a connecting member, and the cross-sectional shape perpendicular to the axis of the main hand is polygonal, at least 1
forming a hand attachment part on the connecting member, which allows a plurality of hands including two suction grips to be attached radially around the axis of the main hand;
It has a surface adjacent to the hand attachment part that slides in airtight contact with the outer peripheral surface of the connecting member, and allows air pressure and vacuum pressure to be passed through the connecting member without being interfered with by the rotation of the connecting member. A main hand, a rotary fluid coupling that can supply fluid to multiple hands, and a main hand,
The plurality of hands, rotational drive device, and connecting member are integrally rotatable around an axis perpendicular to the axis of the main hand, and the axis of the main hand is provided with a two-position swing mechanism horizontally and vertically. It is possible to grip even heavy workpieces with the main hand pointing vertically downward, and if you rotate it around the gripping axis while gripping it, it will hold the main hand vertically downward until it becomes horizontal.
Posture control is possible by swinging 90 degrees, and multiple hands can be used to handle workpieces of various shapes during assembly. can be achieved.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to the drawings.

1 to 3 show the structure of the main parts of an assembly robot according to an embodiment of the present invention, 11 is a main hand, 2 is a rotational drive device, and this main hand 1 and the rotational drive The main hand 1 and the connecting member 3 are connected to the axis of the main hand 1 by connecting the main hand 1 and the connecting member 3 to the main hand 1 in a horizontal coaxial manner and rotating the rotation drive device 2 with the connecting member 3 interposed in the middle. It is possible to rotate around it.

The main hand 1 has three gears 2 that are meshed and arranged in tandem.
1, 21, and 21 are rotatably supported and are connected to the tip of a main hand opening/closing air cylinder (hereinafter abbreviated as air cylinder) 20, which serves as the base of the hand. The structure is such that the gripping pieces 19, 19, in which the gears 21 on the base side are engaged with the racks of the rod with a rack of the air cylinder 20, can be moved in parallel, and by advancing the rod with a rack, the Move the gripping pieces 19, 19 to the open side,
Conversely, by retracting it, it is moved toward the grasping side.

Note that compressed air is supplied to the air cylinder 20 through a connection port 22 provided on the tip side of the connection member 3,
This is done by connecting the air cylinder 23 and the connection port of the air cylinder 20 with a hose.

On the other hand, the rotation drive device 2 is a DC servo motor 9
, a reducer 10 that reduces the rotation of the motor 9 at a predetermined ratio, and an encoder 11 that measures the rotation speed of the servo motor 9 and generates an electric signal proportional to the rotation angle of the output shaft of the reducer 10 are coaxially connected. This frame is fixed to a frame 8 as a cylindrical fixed member, and the output shaft of the reducer 10 is fitted into a shaft hole provided at the center of the base side of the connecting member 3. Make it stick.

Next, the connection member 3 will be explained.
The member 3 serves as a power transmission member for transmitting the rotational power of the rotary drive device 2 to the main body of the air cylinder 20, which is the base of the main hand 1.
and a member that functions as a fluid coupling for supplying compressed air to each hand 6A, 6b to be described later,
The tip part is formed into a prismatic body, for example, a square prism, with a polygonal cross-sectional shape perpendicular to the axis of the main hand 1, and this part serves as the hand attachment part 4, and the rear part of the hand attachment part 4 is made into a cylinder. The rear end portion thereof is rotatably fitted concentrically to the frame 8 via a bearing 24, while a rotary fluid coupling 5, which will be described later, is provided in the intermediate portion adjacent to the hand attachment portion 4.
are engaged.

Thus, the hand attachment portion 4 has four peripheral plane portions each serving as a hand attachment surface, and four hands 6A including at least one suction grip 6A.
-6D are fixed such that their gripping axes are perpendicular to the axis of the main hand 1.

The hand attachment part 4 has a flat end face perpendicular to the axis of the main hand, and is designed to be a mating face and come into sliding contact with the flat end face of the rotary fluid coupling 5 disposed adjacent thereto, and also Fluid passages 33 extending from the attachment center on each of the four planes to the flat end surface are provided rotationally symmetrically with respect to one axis of the main hand.

This fluid passage 33 is communicated with the suction passage of the suction pad by attaching the suction grip 6A to the hand attachment part 4, and when a hand other than the suction grip 6A is attached, it is connected by a blind plate. Make sure to close the opening on the mounting surface.

On the other hand, the rotary fluid joint 5 has a hand attachment portion 4.
The hand mounting portion 4 has a cylindrical body having a surface that serves as an airtight mating surface and slides into contact with the flat end surface of the connecting member 3 and the circular outer circumferential surface at the intermediate portion of the connecting member 3.
Each hand 6A to 6D and main hand 1 attached to
It has ports 25, 26 and a vacuum pressure supply port 12 for supplying compressed air to the pneumatic actuator. The ports 25 and 26 communicate with ring grooves 27 and 28 cut on the outer periphery of corresponding portions of the connecting member 3, respectively, and are sealed with O-rings 29 and 29 to maintain airtight communication. Groove 2
The connecting ports 22 and 23 are connected to the connecting ports 22 and 23 through fluid passages provided in the connecting member 3 in communication with the connecting ports 7 and 28, respectively.

On the other hand, the vacuum pressure supply port 12 is connected to the connecting member 3
so that it can communicate with the fluid passage 33 when it rotates and the fluid passage 33 is located at the vertical lowest position,
It communicates with a fluid passage 33 that opens at a predetermined location on the flat end face of the rotary fluid coupling 5.

In FIG. 3, reference numeral 30 denotes a disc spring interposed between the end of the frame 8 and the opposite end of the rotary fluid coupling 5, which connects the rotary fluid coupling 5 to the hand mounting portion 4.
By pressing to the side, the end surfaces perpendicular to the axis of the main hand are kept airtight and brought into contact with each other.

Further, 31 indicates a pin for positioning the rotary fluid coupling 5 with respect to the frame 8, and 32 indicates a sensor for detecting the origin of the rotation angle of the hand attachment portion 4.

The composite hand thus constructed has a shaft 1 extending perpendicularly to the axis of the main hand 1 on the outer periphery of the frame 8.
5 and connect the frame 8 to the robot arm 17.
The rod of the pneumatic cylinder 14 attached to the support member 18 is rotatably attached to the support member 18 fixed to the tip of the support member 18 via the shaft 15, and a link member 16 is fixed to the shaft 15. and the link member 16 are rotatably connected.

By setting the stroke of the pneumatic cylinder 14, the effective length of the link member 16, and the distance between the shaft 15 and the attachment point of the pneumatic cylinder 14 to have a constant relationship, the pneumatic cylinder 1
If you do 4 rods forward and backward, main hand 1,
Each of the hands 6A to 6D, the rotary drive device 2, and the connecting member 3 can be integrally rotated back and forth at a rotation angle of 90 degrees, and the main hand 1 can be fixed in two positions, horizontal and vertical. , link member 1
6 and the pneumatic cylinder 14 form a two-position swing mechanism 7.

The composite hand having the above-mentioned configuration is constructed by rotating the rotary drive device 2 by a predetermined rotation angle (90° in the illustrated example) in the state shown in the first figure in which the main hand 1 has its axis horizontally, thereby attaching the suction grip 6A. Alternatively, by indexing any of the other hands 6B to 6D vertically downward, it is possible to handle small and light weight workpieces.

At this time, since the suction grip 6A is indexed vertically downward, it automatically communicates with the vacuum pressure supply port 12, thereby ensuring reliable suction by maintaining the vacuum pressure.

Further, by moving the suction grip 6A away from the vertically downward position, the vacuum pressure supply line can be automatically disconnected, so that the operation of attaching and detaching the grip for replacement can be performed easily and quickly.

Furthermore, the main hand 1 can be used to perform horizontal handling in the state shown in the first figure with the axis of the main hand 1 horizontal.

On the other hand, when the two-position swing mechanism 7 is operated so that the axis of the main hand 1 is vertical, it is possible to handle a heavy weight with the main hand 1,
Furthermore, since the rotary drive device 2 can be operated to change the posture by rotating around the gripping axis, it is also possible to handle assembly work such as fitting or screwing together workpieces having irregular cross sections.

(Effects of the Invention) The connecting member 3, which integrally has the hand attachment portion 4 for attaching the plurality of hands 6A, 6B radially around the axis of the main hand 1, interferes with rotation due to the rotary fluid coupling 5. Since it has a fluid passageway that can stably supply air pressure and vacuum pressure to the main hand 1 and the hands 6A and 6B without being connected to the main hand 1 and the square hands 6A and 6B, The piping can be made as short as possible, the problem of piping being routed around the hands is solved, and each hand can be replaced quickly and easily.

The main hand 1 can be made of a heavy weight type, and there is an advantage that a single hand can handle a wide variety of workpieces, regardless of whether they are heavy or light.

Furthermore, since the main hand 1 is rotatable around its own axis, it is possible to change the posture of the workpiece, and while the conventional turret-type compound hand could only handle workpieces, such as fitting and screwing. Assembling operations such as the above are also possible, and a multi-purpose composite hand can be provided.

In addition, the main hand 1 and each hand 6A, 6B can be moved vertically and horizontally by the two-position swing mechanism 7.
Since the direction can be changed, the work scope is expanded, and especially when used as a hand for a horizontally articulated or orthogonal coordinate type robot, it is easy to handle the workpiece in the horizontal direction, and the workpiece can be easily handled horizontally. Compared to conventional devices that require a separate hand, the improvements in terms of cost and control are significant.

[Brief explanation of drawings]

1 and 2 are a schematic front view and a left side view of a robot hand according to an embodiment of the present invention, and a third
The first figure is a cross-sectional front view of the main part of the hand shown in the first figure;
FIG. 5 is a schematic side view and a schematic front view of each example of a conventional robot hand. 1... Main hand, 2... Rotation drive device, 3...
Connection member, 4...Hand mounting portion, 5...Rotary fluid coupling, 6A, 6B...Hand, 7...2 position swing mechanism, 12...Vacuum pressure supply port, 13...Fluid passage.

Claims (1)

[Scope of Claims] 1. A main hand 1 and a rotary drive device 2 are horizontally and coaxially connected via a connecting member 3, and the main hand 1 is
A plurality of hands 6 each having a polygonal cross-sectional shape perpendicular to the axis thereof and including at least one suction grip 6A.
A, 6B can be attached radially around the axis of the main hand 1. A hand attachment part 4 is formed on the connecting member 3, and a hand attachment part 4 is formed on the outer peripheral surface of the connecting member 3 adjacent to the hand attachment part 4. It has a surface that slides into airtight contact, and supplies air pressure and vacuum pressure to the main hand 1 and each hand 6A, 6B through the connecting member 3 without being interfered with the rotation of the connecting member 3. The main hand 1, the plurality of hands 6A, 6B, the rotary drive device 2, and the connecting member 3 are rotatable as a unit around an axis perpendicular to the axis of the main hand 1, and A composite hand characterized by being provided with a two-position swing mechanism 7 that can fix the axis of the main hand 1 in two positions, horizontal and vertical. 2. The rotary fluid joint 5 has an end surface of the hand attachment section 4 that elastically slides into contact with the end surface perpendicular to the axis of the main hand 1, and a fluid passage 13 that opens to the end surface and communicates with the vacuum pressure supply port 12. having
The vacuum pressure supply port 12 is connected to the suction grip 6A only when the suction grip 6A is in the vertically downward position.
The composite hand according to claim 1, which is capable of communicating with A.