JPH0245219Y2 - - Google Patents

Description

[Detailed description of the invention] "Industrial application field" This invention, when stopping and positioning a moving workpiece, moves the part that collides with the workpiece within its range of motion, and stops the workpiece while cushioning it. This invention relates to a cylinder device for a stopper with a shock absorber used for this purpose.

"Prior Art" Conventionally, as this type of cylinder device, the one shown in FIG. 5 is known. In this cylinder device, a main piston 3 having a piston rod 2 projecting thereon is fitted in a cylinder body 1 so as to be slidable up and down, and a return spring 4 is arranged to bias the main piston 3 upward. A shock absorber chamber 5 is formed in the piston rod 2, and a shock absorber 6 is installed in the shock absorber chamber 5 using the piston rod 2 as a shock absorber body as follows.

That is, a buffer piston 7 is fitted in the shock absorber chamber 5 so as to be vertically slidable, and a buffer piston return spring 8 is provided to bias the buffer piston 7 upward. A check valve body 10 is fitted into the valve chamber 9 so as to be slidable up and down, and a valve return spring 12 is provided to press the valve body 10 into contact with a valve seat 11 on the top surface of the valve chamber 9. In addition, the shock absorber chamber 5 is provided with a shock absorber chamber 5 at the upper end, which is threaded through the piston 3 and threaded through the rod guide 13 that closes the upper end opening of the shock absorber chamber 5. The needle 16 is fixed with a cap nut 17. The buffer piston 7 has an upper chamber 5a on its upper side.
A passage 18 is provided which communicates the lower chamber 5b with the lower chamber 5b, and the lower end opening of this passage 18 forms a valve port 19 in the valve seat 11.

An adjustment knob 21 for rotating the adjustment rod 15 is attached to the end cover 20 fitted to the lower end of the cylinder body 1, and a stop lever 23 is attached to the pin 24 of the lever holder 22 fixed to the upper end of the piston rod 2. It is rotatably pivoted by. This stop lever 23 is biased by a torsion spring 25 so as to come into pressure contact with the buffer rod 14. A workpiece receiving roller 26 is rotatably supported at the free end of the stop lever 23 .

The conventional cylinder device configured in this way is
For example, it is installed below the roller 27 of a roller conveyor and is used to cushion and stop the pallet 28 being conveyed thereon, and its operation is as follows.

In the state shown in FIG. 5, when the pallet 28 collides with the workpiece receiving roller 26 and the stop lever 23 is rotated, the stop lever 23 pushes down the buffer rod 14, and accordingly the buffer piston 7
The buffer piston moves downward against the return spring 8, and the oil in the lower chamber 5b flows into the upper chamber 5a through the passage 18 while being throttled by the chuck valve body 10, thereby providing a buffering effect. As a result, the pallet 28 is stopped at a predetermined position while being buffered. When the main piston 3 is lowered by feeding pressure fluid through a port 29 provided in the cylinder body 1, the piston rod 2 is also lowered and the stop lever 23 is moved to a retracted position below the roller 27. At this time, the stop lever 23 is separated from the pallet 28, the buffer piston 7 is returned upwardly by the buffer piston return spring 8, and the stop lever 23 is moved away from the pallet 28.
3 is rotated back while being pushed up by the buffer rod 14.

"Problems to be Solved by the Invention" However, in this conventional cylinder device, the stop lever 23 is rotated back to push the pallet 28 which has been stopped due to the return force of the shock absorber 6, so that the pallet 28 is If the stop position shifts, for example, if a workpiece is placed on top of the stop position, the machining position shifts and the machining position must be corrected.

The purpose of the present invention is to easily solve these problems.

``Means for Solving the Problems'' The present invention includes a lever lock mechanism that locks the stop lever when it is rotated in the direction of the stop action and releases the lock when the piston rod is moved to a predetermined position in the retraction direction. It is characterized by being attached to the piston rod.

``Function'' Therefore, the lever lock mechanism once suppresses the return circuit of the stop lever after the shock absorber acts, and the suppressed state is released when the piston rod moves to a predetermined position in the retracting direction.

"Embodiment" An embodiment of the present invention will be described below in detail based on FIGS. 1 to 4.

In FIG. 1, a main piston 32 is provided with a piston rod 31 integrally projecting inside the cylinder body 30.
is fitted so that it can slide up and down. A port 33a is provided on the mounting collar 33 on the outer peripheral surface of the cylinder body 30. Both the piston rod 31 and the main piston 32 are hollow, and the piston rod 31
The main piston 32 has a shock absorber mounting hole 34 eccentric from its centerline, and the main piston 32 has an opening 35 communicating with the shock absorber mounting hole 34. The piston rod 31 and the main piston 32 are urged upward by a return spring 37 via a spring receiver 36 fitted in the hollow portion thereof. Both outer surfaces 31a of the piston rod 31 are flat surfaces perpendicular to the cylinder body 30 so as not to rotate, and a guide piece 38 is provided on the upper end surface of the cylinder body 30 for slidingly guiding the flat outer surface 31a. attached.
A proximity switch 40 that reacts with the spring receiver 36 is attached to an end cover 39 that closes the lower end opening of the cylinder body 30, and detects that the piston 33 has descended to a predetermined position. A shock absorber 41 is removably inserted into the shock absorber mounting hole 34.

This shock absorber 41 has all its components built into a dedicated shock absorber body 42, and as shown in FIGS.
It has an independent structure.

That is, an inner cylinder 43 is rotatably fitted into the shock absorber body 42, a buffer piston 44 is fitted into the inner cylinder 43 so as to be vertically slidable, and the buffer piston 44 is moved upwardly by a return spring 45. It is biased towards. The upper end 43a of the inner cylinder 43 projects outward from the upper end of the shock absorber main body 42, and a rod cover 46 is fitted within the upper end 43a. The buffer piston 44 has a spring guide rod 47 projecting from its lower side and a buffer piston rod 48 projecting from its upper side. This buffer piston rod 4
8 slidably passes through the rod cover 46 and has an upper end 48a protruding outward from the inner cylinder 43. A communication hole 49 and a plurality of orifices 50 are bored in the peripheral wall of the inner cylinder 43 . Further, the outer circumferential surface of the inner cylinder 43 is provided with upper and lower recesses that form upper and lower gap passages 51 and 52 between it and the inner circumferential surface of the shock absorber body 42. Both gap passages 5
1 and 52 are communicated with each other by a groove (not shown) formed on the outer peripheral surface of the inner cylinder 43,
Further, the upper gap passage 51 communicates with the communication hole 49,
The lower gap passage 52 communicates with an accumulation chamber 53, which is a recess formed in the outer peripheral surface of the inner cylinder 43. This storage chamber 53 is filled with an expansion/contraction material 54 . On the other hand, the shock absorber body 4
A throttle adjustment groove 55 that coincides with the orifice 50 is formed on the inner circumferential surface of No. 2 . This aperture adjustment groove 55
extends in the circumferential direction of the shock absorber main body 42 while gradually becoming narrower in width, and
It's getting shallower.

Therefore, when a load is applied to the buffer piston rod 48 from the outside and it slides against the return spring 45, the oil under the buffer piston 44 is squeezed through the orifice 50 and the throttle adjustment groove 55 and flows through the gap passage 52. flows into the storage chamber 53 through the gap passage 5 and acts on the expansion/contraction material 54.
1 and the communication hole 49 into the chamber above the buffer piston 44, and the buffering action of the buffer piston 44 is performed. The operation of the buffer piston 44 can be adjusted by rotating the inner cylinder 43 with respect to the shock absorber body 42 and changing the alignment of the orifice 50 and the throttle adjustment groove 55 in the circumferential direction. In order to make the adjustment, an operating pin 56 is provided protruding from the outer peripheral surface of the upper end 43a of the inner cylinder 43, and an operating pin 56 is provided on the shock absorber body 42 to restrict the rotation of the inner cylinder 43 after the adjustment. A lock screw 57 is screwed into the screw hole.

Shock absorber 41 configured in this way
As shown in FIG. After insertion, a lock screw 60 screwed into the screw hole 59 of the piston rod 31 restricts extraction and rotation. In this inserted state,
The screw 57 of the shock absorber body 42 matches the operation hole 61 bored in the piston rod 31,
The operating pin 56 is located outside the shock absorber mounting hole 34.

In addition, when installing the shock absorber body 42,
It is also possible to form a male thread on the outer circumferential surface and a female thread on the inner circumferential surface of the shock absorber mounting hole 34, and screw these male and female threads together.

On the other hand, as shown in FIGS. 1 and 2, a shock absorber 41 is provided at the upper end of the piston rod 31.
A stop lever 62 is pivotally mounted, and a lever lock mechanism for locking the stop lever 62 is mounted.

That is, the stop lever 62 is rotatably supported by a pin 63 between a pair of bearing protrusions 31b integrally provided on the upper end surface of the piston rod 31. This stop lever 62 is biased counterclockwise in FIG. 1 by a torsion spring 64.
The lower end surface is brought into pressure contact with the upper end of the buffer piston rod 48. A workpiece receiving roller 65 is rotatably supported on the upper free end of the stop lever 62, and a lock pin 66 is implanted on one side of the lower free end. A bracket 67 is attached to the vertical and flat outer surface 31a of the piston rod 31 by a bolt 68 and a spring-loaded screw 69, and a lock lever 70 having a dogleg shape on the side is attached to the bracket 67 by a pin 71. It is pivoted in the middle so that it can rotate freely. The upper free end of the lock lever 70, which is U-shaped in plan, is a pin abutting part 70a that comes into contact with the lock pin 66, and the lower side thereof is a hook part 70b that engages the lock pin 66. Lock lever 70 is torsion spring 7
2 in the clockwise direction in FIG.
It is in pressure contact with. When the piston rod 31 is lowered to a predetermined position, the lower free end 70c of the lock lever 70 comes into contact with the guide piece 38 on the cylinder body 30, and is rotated counterclockwise in FIG.

The cylinder device thus constructed is installed, for example, below the roller 73 of a roller conveyor in FIG. 1, and is normally in the state shown in the figure. When the pallet 74 conveyed on the roller 73 of the roller conveyor collides with the workpiece receiving roller 65, the stop lever 62 is rotated counterclockwise in FIG.
8 is pushed down and the damping effect is performed as described above. At this time, the lock pin 66 of the stop lever 62 rotates the lock lever 70 slightly and engages with its hook 70b, and the stop lever 62 is locked, that is, its rotation in the clockwise direction in FIG. 1 is restricted.
This state is maintained even after the shock absorber 41 finishes its damping action. Therefore, the pallet 74 will not be moved backward after stopping due to the return rotation of the stop lever 62 accompanying the return movement of the shock absorber 41.

When pressure fluid is introduced into the cylinder body 30 through the port 33a and the main piston 32 and piston rod 31 are lowered, the stop lever 62 is moved below the roller 73. When the piston rod 31 has been lowered to a predetermined position, the lower free end 70c of the lock lever 70 collides with the guide piece 38 and is rotated counterclockwise in FIG. 62 is automatically unlocked. When the pressure fluid is discharged from port 33a, piston 32 and piston rod 31 are raised by return spring 37 and return to the state shown in FIG.

``Effect of the invention'' As described above, according to the cylinder device of the present invention, the lever lock mechanism once suppresses the return rotation of the stop lever after the shock absorber acts, and the piston rod moves to a predetermined position in the retracting direction. Since the suppressed state can be canceled at the same time, there is no problem that the position of the workpiece (object to be stopped) shifts after it is stopped due to the return rotation of the stop lever.

[Brief explanation of the drawing]

Figures 1 to 4 show an embodiment of the present invention, with Figure 1 being an overall partially cutaway side view, Figure 2 being an exploded perspective view,
FIG. 3 is a side view of the shock absorber, FIG. 4 is a plan view thereof, and FIG. 5 is a sectional view of a conventional example. 30... Cylinder body, 32... Main piston,
31... Piston rod, 62... Stopping lever,
41...Shock absorber, 70...Lock lever.

Claims (1)

[Scope of utility model registration request] A main piston is slidably fitted into the cylinder body, and a stop lever is rotatably pivoted to the tip of a piston rod protruding from the main piston. can be displaced between a restraining position and a retracting position,
In addition, in a stopper cylinder device with a shock absorber built into the piston rod, which buffers the rotation of the stop lever in the direction of braking action, the stop lever is locked when it is rotated in the direction of braking action, and the piston rod is locked. A cylinder device for a stopper with a shock absorber, characterized in that a lever lock mechanism is attached to the piston rod to release the lock when the piston rod is moved to a predetermined position in the retracting direction.