JP2545725B2 - Shock absorber for robot for forging work - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a related art of a robot for forging work which is applicable not only to die forging such as hammer forging but also to press forging. A shock absorber for a forging robot that performs a shock absorbing function by vertically and horizontally displaceably holding a grip portion that grips a work against an impact force during forging by the action of two sets of parallel links arranged at the front and rear. It is about.

[0002]

2. Description of the Related Art In the case of forging work, especially hammer-type forging, manual work has conventionally been the main work, and there has been no effective handling robot.

[Problems to be Solved by the Invention]

By the way, in the forging work, especially in the hammer die forging, when the automation of handling is considered, it is required to grip and punch the end of the work, but in this case, the work is momentarily caused by the impact force during the forging. It is conceivable that the gripper may be displaced in the vertical direction and the gripper may extend in the horizontal direction. Therefore, the gripper for gripping the work requires a shock absorber in the vertical and horizontal directions.

Further, in many cases, the hammer is installed on a suspension foundation, and the hammer itself causes the hammer itself to largely move up and down by hitting the hammer. This vertical movement may reach 20 to 30 mm, and when the grip portion is directly attached to the robot arm, an excessive bending force is applied to the robot arm, which may cause damage to the robot.

It is impossible to completely buffer the impact at the time of hitting, the deformation of the work, and the ups and downs of the hammer only with the grip portion, and some kind of buffering device for protecting the robot is required.

The present invention has been made in view of the above-mentioned problems and was devised to solve the problems. The object of the present invention is to dispose the robot arm and the grip part in front and back. By the function of two sets of parallel links and the cylinder mechanism that holds them, the grip part that holds the workpiece against the impact force during forging is held displaceably in the vertical and horizontal directions to fulfill the cushioning function, and the initial position To provide a shock absorbing device for a forging robot capable of returning to a normal state.

[0007]

In order to achieve the above object, the present invention is pivotally supported between a robot arm and a grip portion of a forging robot so as to be vertically rotatable.
In addition, parallel links in which the links are arranged side by side are arranged in the front and back, and each fluid pressure cylinder mechanism that holds each parallel link rotatably in the vertical direction is provided. And a structure for holding it so as to be displaceable in the horizontal direction.

Here, the two fluid pressure cylinder mechanisms for holding the parallel links are of an intermediate stop type capable of neutral return, and the fluid pressure is applied to the fluid pressure cylinder mechanisms so that the parallel links are always held in a fixed posture. Only when an impact force is applied, the fluid pressure cylinder mechanism and the parallel link can be displaced to absorb and relax the impact, and then automatically return to the original position.

[0009]

The present invention having the above-described structure operates as follows. That is, when a vertical impact force is applied to a work during forging, a cylinder mechanism that holds the parallel link through a parallel link pivotally supported between the grip portion and the robot arm in a vertically rotatable manner. The impact force acts on the two parallel links by changing their relative angles and displacing the parallel links downward in parallel with the central axis of the original robot arm to alleviate the impact force.

Similarly, when a horizontal impact force is applied to the work, the impact force acts on the cylinder mechanism in the same manner as described above, changing the relative angle of each of the two sets of parallel links, and the original robot. It displaces in the horizontal direction parallel to the arm center axis, and acts to mitigate the impact force.

Further, similarly, when a vertical and horizontal impact force is applied to the work, the above-described action simultaneously performs vertical and horizontal displacements parallel to the original robot arm center axis to alleviate the impact force. Act as you do.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described more concretely with reference to the embodiments shown in the drawings. Here, FIG. 1 is an overall side view, FIG. 2 is an overall plan view, FIG. 3 is an overall operation view, and FIG.
(C) is operation explanatory drawing of a principal part, FIG. 5 is a side view of a principal part of another embodiment, and FIG. 6 is a sectional view of a cylinder mechanism.

In the figure, a robot arm 2 is movably attached to a robot body 1 of a robot for forging work, and a shock absorber 4 is attached between the robot arm 2 and the grip portion 3. A work gripping portion 3a for directly gripping the work W is attached to the tip of the grip portion 3.

The shock absorber 4 is a device for preventing an impact force acting on the grip portion 3 holding the work W during forging from being transmitted to the robot arm 2, and includes two sets of parallel links 5 and 6 connected to the front and rear, and It is mainly composed of cylinder mechanisms 7 and 8 for holding the parallel links 5 and 6.

Each of the parallel links 5 and 6 has an upper link piece 5
a, the lower link piece 5b, the upper link piece 6a, and the lower link piece 6b are arranged in parallel vertically. Both ends of each of the link pieces 5a, 5b, 6a, 6b are adjacent to the grip portion 3, the central coupling link 9 and the robot arm 2.
, The connection pins 10 and 1 are respectively rotatable in the vertical direction.
1, 12 are connected and supported.

Of these, the front end side of each of the link pieces 5a and 5b of the front parallel link 5 is at the rear end of the grip portion 3,
Further, the rear end side is connected to the coupling link 9, and the connecting pins 10 and 1 are respectively provided.
1 is connected so as to be vertically rotatable. Each of the link pieces 6a and 6b of the rear parallel link 6 has its front end side connected to the connecting link 9 and its rear end side to the tip end of the robot arm 2 by connecting pins 11 and 12 so as to be vertically rotatable. There is.

Link pieces 5a, 5b of the front parallel link 5
The rear end side and the link pieces 6a, 6b of the rear parallel link 6
The front end side of the cross section intersects with the coupling link 9 and is rotatably coupled vertically by the same coupling pin 11. In this case, the front parallel link 5 is inclined obliquely upward at the rear end side, and the rear parallel link 6 is inclined obliquely upward at the front end side so as to intersect on the connecting link 9 and turn up and down with the same connecting pin 11. It is rotatably connected. Front parallel link 5
The rear parallel link 6 and the rear parallel link 6 are connected to each other by a connecting pin 11.

The front and rear cylinder mechanisms 7, 8 are devices for holding the parallel links 5, 6 rotatably in the vertical direction. The cylinder mechanisms 7, 8 are fluid pressured to the cylinder mechanisms 7, 8 as shown in FIG. 6, for example. The pistons 7a, 7b, 8a, 8b for advancing and retracting are built in respectively, and the front ends of the pistons 7a, 8a project from the front parts of the cylinder mechanisms 7, 8.

Fluid pressure is constantly supplied to the pistons 7a and 8a on the rod side and to the pistons 7b and 8b on the head side, and the pistons 7a and 8a are normally held at the neutral position in the center of the stroke. When a pulling force acts on the pistons 7a and 8a, the pistons 7a and 8a are pulled out and the fluid on the rod side is pushed out and absorbed by the accumulator 19. On the contrary, when the pushing force acts on the pistons 7a and 8a, the pistons 7a and 8a are pushed in, the fluid on the head side of the pistons 7b and 8b is pushed out, and flows into the pistons 7a and 8a side, and at the same time, excess fluid is stored in the accumulator 19 Is absorbed by.

Of these, the front cylinder mechanism 7 holds the front parallel link 5, and the rear cylinder mechanism 8 holds the rear parallel link 6. Although not shown here, the pressure of each cylinder mechanism 7 and 8 is adjusted so that the work W is gripped by the grip portion 3 and is balanced with the weight thereof.

The front cylinder mechanism 7 is attached downward to the upper part of the inverted L-shaped coupling link 9 which projects forward. The front cylinder mechanism 7 is connected and supported by a support pin 13 so as to be vertically rotatable. The piston 7a of the front cylinder mechanism 7 is directed downward, and the tip of the piston 7a is located below and the piston pin 1 is attached to the upper link piece 5a inclined obliquely downward toward the front.
It is connected by 4 so as to be rotatable in the vertical direction.

The rear cylinder mechanism 8 is horizontally attached to the upper end of the robot arm 2 toward the front.
The rear cylinder mechanism 8 is connected and supported by a support pin 15 so as to be vertically rotatable. The piston 8a of the rear cylinder mechanism 8 is directed forward, and the tip of the piston 8a is vertically rotatable by a piston pin 16 on an upper link piece 6a located forward and inclined obliquely upward toward the front. It is connected.

The operation based on the configuration of the above embodiment will be described below. When the forging work is performed here, the work W at the tip is fitted into the mold and is displaced downward at the same time, and at the same time, the work W extends horizontally toward the work gripping portion 3a.

Although not shown, the grip portion 3 is provided with vertical and horizontal displacement buffers to absorb most of the vertical and horizontal displacements, but the displacement that cannot be completely absorbed is gripped. It acts on the shock absorber 4 mounted at the rear end of the part 3.

In the shock absorber 4, the front parallel link 5 and the rear parallel link 6 rotate up and down with the connecting pins 10, 11 and 12 as pivotal fulcrums, and the upper link pieces 5a and 6a receive the piston pins 14 and 6, respectively. The pistons 7a and 8a of the cylinder mechanisms 7 and 8 whose tips are connected at 16 are displaced to displace the grip portion 3 in parallel with the central axis of the robot arm 2.
It will dampen vertical and horizontal displacement.

For example, as shown in FIG. 4 (A), when the displacement of the grip portion 3 acts downward, the pistons 7a and 8a of the cylinder mechanisms 7 and 8 extend and the front parallel link 5 The inclination angle of each link piece 5a, 5b becomes large, the inclination angle of each link piece 6a, 6b of the rear parallel link 6 becomes small, and the grip portion 3 does not move back and forth,
Displace only downward while maintaining horizontal. Therefore,
The shock absorber 4 absorbs and absorbs the downwardly acting displacement to prevent the displacement from acting on the robot arm 2.

Further, as shown in FIG. 4B, when the displacement of the grip portion 3 acts in the horizontal contraction direction, the piston 7a of the front cylinder mechanism 7 extends and the rear cylinder mechanism 8 moves. Piston 8a moves backward, the inclination angle of each link piece 5a, 5b of the front parallel link 5 increases,
Further, the inclination angle of each link piece 6a, 6b of the rear parallel link 6 also becomes large, so that the grip portion 3 does not move up and down, but is displaced only rearward while keeping horizontal. Therefore, the shock absorber 4 absorbs and buffers the displacement acting in the horizontal contraction direction to prevent the displacement from acting on the robot arm 2. In this case, when the intervals between the connecting pins 10 and 11 and the connecting pins 11 and 12 are the same, the inclination angles of the front parallel link 5 and the rear parallel link 6 are the same.

Furthermore, as shown in FIG. 4 (C),
When the displacement of the grip portion 3 acts upward, the pistons 7a and 8a of the cylinder mechanisms 7 and 8 retreat, the inclination angles of the link pieces 5a and 5b of the front parallel link 5 decrease, and the rear parallel The inclination angle of each of the link pieces 6a and 6b of the link 6 becomes large, the grip portion 3 does not move forward and backward, and is displaced only upward while keeping horizontal. Therefore, the cushioning device 4 absorbs and cushions the displacement acting upward, and prevents the displacement from acting on the robot arm 2.

As shown in FIG. 3, when the grip portion 3 is pressed obliquely from the front upper side, only the piston 7a of the front cylinder mechanism 7 extends, and the grip portion 3 is displaced obliquely rearward and downward to cause the robot to move. The displacement of the arm 2 is prevented.

When the external force acting on the grip portion 3 disappears, the cylinder mechanisms 7, 8 that have just been displaced return to their neutral positions, and the front parallel links 5 and the rear parallel links 6 will return to their initial positions.

The present invention is not limited to the above embodiments, and it goes without saying that various modifications can be made without departing from the spirit of the invention. For example, in the above embodiment, the rear end side of the front parallel link 5 and the rear parallel link 6 are connected.
Although the description has been given of the case where the front end sides of are crossed and connected by the same connecting pin 11, the invention is not limited to this.
As shown in FIG. 5, separate connecting pins 17 and 18 may be connected so as to be vertically rotatable.

Further, the front cylinder mechanism 7 is connected to the coupling link 9
Although the case where the grips 3 are connected and supported has been described above, the present invention is not limited to this and may be connected and supported on the rear end side of the grip portion 3. Similarly, the case where the rear cylinder mechanism 8 is connected and supported to the upper portion on the tip side of the robot arm 2 has been described, but the present invention is not limited to this, and the rear cylinder mechanism 8 may be connected and supported on the coupling link 9.

[0033]

As is apparent from the above description, according to the shock absorbing device for a forging robot according to the present invention, two sets of parallel links arranged in the front and rear are provided between the robot arm and the grip portion. By the function of the cylinder mechanism that holds the work piece, the grip part that holds the workpiece against the impact force during forging is held displaceably in the vertical and horizontal directions to perform a cushioning function and prevent the displacement from acting on the robot arm. be able to. The vertical and horizontal displacement of the tip grip part is always parallel to the robot arm axis, and it is also possible to respond to shock displacement, and it is possible to return to the initial position, improving the safety of the robot body. It is possible to bring about an extremely new and beneficial effect.

[Brief description of drawings]

FIG. 1 is an overall side view showing an embodiment of the present invention.

FIG. 2 is an overall plan view showing an embodiment of the present invention.

FIG. 3 is an overall operation diagram showing an embodiment of the present invention.

4 (A) to 4 (C) are operation explanatory views of the main part of the embodiment of the present invention.

FIG. 5 is a side view of a main portion of another embodiment of the present invention.

FIG. 6 is a sectional view of a cylinder mechanism used in an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Robot main body 2 ... Robot arm 3 ... Grip part 3a ... Work holding part 4 ... Buffer device 5 ... Front parallel link 5a ... Upper link piece 5b ... Lower link piece 6 ... Rear parallel link 6a ... Upper link piece 6b ... Lower link piece 7 ... Front cylinder mechanism 7a, 7b ... Piston 8 ... Rear cylinder mechanism 8a, 8b. ..Piston 9 ... Coupling link 10, 11, 12, 17, 18, ... Connecting pin 13, 15 ... Support pin 14, 16 ... Piston pin 19 ... Accumulator

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-293794 (JP, A) JP-A-1-264785 (JP, A) Practical application Sho-48-53063 (JP, U)

Claims (2)

(57) [Claims] 1. A parallel link, which is pivotally supported in a vertically rotatable manner and in which the links are vertically arranged, is arranged between the robot arm and the grip portion of the forging work robot, and the parallel links are arranged in front and back. A buffer for a forging robot characterized in that each fluid pressure cylinder mechanism that holds the parallel link rotatably up and down is provided, and the grip part is held so as to be vertically and horizontally displaceable with respect to the robot arm. apparatus. 2. The two fluid pressure cylinder mechanisms for holding the parallel links are of an intermediate stop type capable of returning to a neutral state, and the fluid pressure is applied to the fluid pressure cylinder mechanisms so that the parallel links are always held in a fixed posture and impact is exerted. The buffer for a forging robot according to claim 1, wherein the fluid pressure cylinder mechanism and the parallel link are displaced only when a force is applied to absorb and relieve the shock, and then automatically return to the original position. apparatus.