JP3328831B2 - Clamping device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp device for clamping a work such as a plate material in order to hold the work in a fixed position when performing a process such as welding.

[0002]

2. Description of the Related Art Conventionally, when a metal thin plate used in an automobile or the like is assembled by welding or the like, a pneumatic cylinder is used as a clamping device for positioning and clamping using a hole provided in the thin plate. Those shown in FIG. 4 are used.

In this conventional clamp device, a positioning pin 3 is projected from a clamp body 2 integral with a cover 1a of a pneumatic cylinder 1, and a pair of clamp arms 4 (only one is shown) having a hook-like tip and an air pressure A pin 6 is used to connect the piston rod 5 of the cylinder 1 with a pin 6, and a bent guide groove 7 is provided in each clamp arm 4, and a guide pin 8 provided in the clamp body 2 is fitted into the guide groove 7. .
Then, while the pneumatic cylinder 1 is fixed at a fixed position, the positioning pin 3 is inserted into the hole 10 provided in the work 9 which is a thin plate to determine the position.
Of the work 9 is inserted into and removed from the hole 10 of the work 9, and the pair of clamp arms 4 are swung by an appropriate amount by the reciprocation of the piston rod 5, so that the work 9 Was able to be clamped and released.

[0004]

However, when the clamp 9 is released and the work 9 is separated from the clamp body 2, the edge of the hole 10 changes from the state where the work 9 is in contact with the distal end surface of the clamp body 2 to the positioning pin 3. Since the work 9 and the positioning pin 3 are separated while sliding on the peripheral surface of the work, the work 9 which is a thin plate may be deformed.

It is an object of the present invention to prevent such deformation when the clamp is released and the work is separated from the clamp body.

[0006]

In the clamping device according to the present invention, the pneumatic cylinder is mounted on the guide frame so as to be movable in the axial direction, and is urged in the extension direction of the piston rod by a spring, so that the piston of the pneumatic cylinder is moved. In addition, a stopper rod which protrudes to the opposite side of the piston rod and regulates the position of the piston with respect to the guide frame is provided in a protruding manner. And, in the clamp state where the clamper clamps the work, the piston and the piston rod of the pneumatic cylinder retreat while the pneumatic cylinder is held at a predetermined position by a spring,
In the unclamped state where the clamper releases the clamp, the piston is propelled to the point where it is regulated by the stopper rod and the piston rod advances, and when the air pressure is further applied to the piston from the unclamped state, the piston is moved by the guide frame with the stopper rod. The pneumatic cylinder retracts against the guide frame together with the clamp body against the spring while the movement with respect to is restricted.

[0007] With this configuration, after the clamp body is in the unclamped state, the clamp body together with the positioning pin can be retracted from the work and separated from the work.

When the stopper rod is provided with a stopper capable of adjusting the regulating position of the piston, the above-described operation after the release of the clamp can be adjusted.

When the cover of the pneumatic cylinder is slidably fitted on the guide rod of the guide frame, the pneumatic cylinder can be moved in a stable state with respect to the guide frame.

When a collar for determining the position of the pneumatic cylinder held by the spring is fitted to the guide rod, the positions of the pneumatic cylinder and the clamp body during clamping can be determined by the collar.

[0011]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 1, a clamp device according to the present invention comprises a pair of clamps having positioning pins 3 projecting from a clamp body 2 integral with a rod-side cover 1a of a pneumatic cylinder 1 and having a hook-shaped tip. The arm 4 (only one is shown) and the piston rod 5 of the pneumatic cylinder 1 are connected by a pin 6, and each clamp arm 4 is provided with a bent guide groove 7, which is provided in the clamp body 2. The fact that the guide pins 8 are fitted is the same as the conventional example shown in FIG. 4, but the following configuration is added.

That is, in order to make the pneumatic cylinder 1 itself movable, a guide frame 11 for mounting the pneumatic cylinder 1 is provided, and a stopper rod 13 protrudes from the piston 12 of the pneumatic cylinder 1 on the side opposite to the piston rod 5. The stopper rod 13 projects outward from the head-side cover 1b opposite to the rod-side cover 1a.

The guide frame 11 is formed by connecting guide plates 14 and 15 on both sides with a plurality of guide rods (tie rods) 16. The connection is effected by screwing the tip screw portion 16a of each guide rod 16 into the screw hole 14a of one guide plate 14, and tightening the nut 17 on the other guide plate 15 side.

The pneumatic cylinder 1 has covers 1 on both sides thereof.
A guide rod 16 is slidably penetrated through a guide hole 1c provided in a.1b, and is mounted on the guide frame 11 so as to be movable in the axial direction along the guide rod 16. The clamp body 2 slidably penetrates a bush 18 fitted in a hole of the guide plate 14, and the stopper rod 13 slidably penetrates a guide hole 15 a of the guide plate 15.

A collar 19 serving as a stopper is fitted on each guide rod 16 on the guide plate 14 side. On the other hand, on the guide plate 15 side, a spring 20 is disposed between the guide plate 15 and the head-side cover 1b of the pneumatic cylinder 1, and the rod-side cover 1a of the pneumatic cylinder 1 is urged by the spring 20. The collar 19 is held at a predetermined position in contact with the collar 19. Spring 2
Reference numeral 0 denotes a coil spring that allows the stopper rod 13 to penetrate.

At the tip of the stopper rod 13 penetrating the guide hole 15a of the guide plate 15, a disc-shaped stopper 21 is provided.
However, the screw portion 21a is screwed into the screw hole 1 of the stopper rod 13.
3a.

In the above configuration, as shown in FIG. 1, the positioning pin 3 is inserted through the hole 10 of the work 9, the rod side cover 1a of the pneumatic cylinder 1 contacts the collar 19, and the pneumatic cylinder 1 is When the piston 12 is retracted while being held at a predetermined position by the spring 20, the clamp arm 4 rotates slightly clockwise while being pulled by the piston rod 5, and its tip hook 4a.
However, the work 9 is clamped by pressing the work 9 against the distal end surface of the clamp body 2. At this time, the stopper 21 of the stopper rod 13 is separated from the guide plate 15.

Next, when the piston 12 is advanced from the state shown in FIG. 1 to advance the piston rod 5, as shown in FIG. 2, the pneumatic cylinder 1 is held at the same position as in FIG. Is rotated slightly counterclockwise while being pushed by the piston rod 5, and the tip hook portion 4a is separated from the work 9 to be in the unclamped state. When the stopper 21 of the stopper rod 13 comes into contact with the guide plate 15, the advance of the piston 12 is restricted. This restriction position can be adjusted by the stopper 21.

When the pneumatic pressure is further applied to the piston 12 from the state of FIG. 2 in which the advance of the piston 12 is restricted, the piston 12 cannot advance, so that the pneumatic cylinder 1 itself moves along the guide rod 16 as shown in FIG. fall back. As a result, the clamp body 2 is also guided by the bush 18 and retreats, so that the distal end surface of the clamp body 2 separates from the work 9 and the positioning pin 3 is pulled out halfway into the hole 10 of the work 9.

Accordingly, when the clamp 9 is released and the work 9 is separated from the clamp body 2, sliding contact between the work 9 and the positioning pins 3 and the distal end surface of the clamp body 2 can be avoided, and the work 9 may be deformed. Disappears.

In the above embodiment, the arm is used as the clamper for clamping the work. However, the clamp is not limited to the arm, but may be any as long as it can be clamped and released by moving the piston rod forward and backward.

[0023]

As described above, according to the present invention, after releasing the clamp, the pneumatic cylinder itself can be retracted, and the clamp body can be retracted with the positioning pin with respect to the work to be separated from the work. ,
The situation that deforms the work is eliminated.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, showing a state where a work is clamped.

FIG. 2 is a cross-sectional view in a state where a clamp is released.

FIG. 3 is a cross-sectional view showing a state in which the pneumatic cylinder itself is retracted after the clamp is released.

FIG. 4 is a sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pneumatic cylinder 1a Rod side cover 1b Head side cover 1c Guide hole 2 Clamp body 3 Positioning pin 4 Clamp arm (clamper) 4c Tip hook 5 Piston rod 6 Pin 7 Guide groove 8 Guide pin 9 Work 10 Work hole 11 Guide frame DESCRIPTION OF SYMBOLS 12 Piston 13 Stopper rod 13a Screw hole 14.15 Guide plate 14a Screw hole 15a Guide hole 16 Guide rod 16a Tip screw part 17 Nut 18 Bush 19 Collar 20 Spring 21 Stopper

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B23Q 3/06 304

Claims (4)

(57) [Claims] The present invention has a clamper connected to the tip of a piston rod of a pneumatic cylinder, and a positioning pin projecting from a clamp body integral with a cover of the pneumatic cylinder. In a clamp device that clamps the work with the clamper by retracting the piston rod and releases the clamp by advancement of the piston rod, the pneumatic cylinder is mounted on the guide frame so as to be movable in the axial direction, and the spring is attached to the spring. To urge the piston rod in the advance direction,
A stopper rod is provided on the piston of the pneumatic cylinder to protrude in a direction opposite to the piston rod and regulates the position of the piston with respect to the guide frame. In the unclamped state in which the piston and piston rod of the pneumatic cylinder are retracted while being held at the predetermined position and the clamper releases the clamp, the piston is propelled to the point regulated by the stopper rod and the piston rod advances, When air pressure is further applied to the piston from the unclamped state, the pneumatic cylinder is retracted against the guide frame together with the clamp body against the spring while the piston is restricted from moving with respect to the guide frame by the stopper rod. A clamping device, characterized in that: 2. The stopper rod according to claim 1, wherein the stopper rod is provided with a stopper capable of adjusting a regulating position of the piston.
The clamp device according to claim 1. 3. The system according to claim 1, wherein the cover of the pneumatic cylinder is slidably fitted on the guide rod of the guide frame.
Or the clamp device according to 2. 4. The clamping device according to claim 3, wherein a collar for determining a position of the pneumatic cylinder held by a spring is fitted to the guide rod.