JP2588161Y2 - Actuator - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a fluid pressure actuator. The actuator of the present invention is used in various industrial equipment such as production equipment.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 9, an actuator for supplying a fluid pressure into a cylinder tube 1 to reciprocate a piston 2 and a rod 3 connected to the piston 2 is known. Piston 2 and rod 3
Are fixed to each other by a screw-in type tightening member 4 and a spacer 5, so that they are configured to always move together.

This actuator is used, for example, to transfer a work by attaching a suction pad or a chuck cylinder to the tip (left end in the figure) of the rod 3, or to insert or press-fit the work into a predetermined location. Can be

[0004] Then, in the actuator of this is,
Since the piston 2 and the rod 3 are integrally connected, the thrust of the actuator may directly act on the work as an impact. That is, when a suction pad is attached to the tip of the rod 3, the rod 3 is moved forward together with the piston 2, and the suction pad is brought into contact with the work to adsorb the work, the moment the suction pad comes into contact with the work, the actuator is turned off. The thrust acts directly on the work as an impact, and the work may be broken by the impact. In addition, when a case where a work is inserted or press-fitted into a predetermined position is considered, this inconvenience appears as a failure of insertion or press-fitting.

In Japanese Utility Model Publication No. 48-25472,
Absorbs and reduces external impact acting on the rod
The piston 3 slidably fitted into the cylinder 1
A fitting hole 4 is formed in the fitting hole 4, and the end of the rod 5 is inserted into the fitting hole 4.
Slidably fit and remove the piston 3 from the end of the rod 5
To lock the nut 6 and the stopper 8 for preventing
5, a stopper 7 is provided.
A disc spring 10 which is an elastic body is interposed between the end face and the end face.
A rendering device is described.

[0006]

[Problems to be solved by the invention] In this prior art
"If used as a lift arm cylinder,
In this case, the impact force generated on the bucket is
To the bottom 5 and push it to the bottom (to the right in the figure).
The oil on the bottom side is pressurized and the piston 3 is moved to the head side.
Press For this purpose, the piston 3 compresses the disc spring 10
This compression is applied to the end face 3a of the piston 3 when the piston 3 stops.
Continue until it collides with par 7. (8th page, right column, page 1)
~ Line 14), but ultimately a rod
At the bottom side (right side in the figure) is provided with a disc spring 10
Directly collides with the stroke limiter.

[0007] Oil is supplied to the bottom side of the cylinder.
The pressure of the oil acts on the piston 3 and the piston 3
The head side together with the rod 5 while compressing the disc spring 10
(Leftward in the figure) and the stopper 7 limits the stroke
(Not shown) and the piston 3
Continue until it contacts the topper 7.

Therefore, when the rod 5 moves during its movement,
When the plate is in contact with the
A buffer effect can be obtained between the piston 5 and the piston 3.
However, when the piston 3 comes into contact with the stopper 7,
The elasticity of the rod 10 does not work, and the rod
If you stop in contact with it, sooner or later
A situation occurs that is transmitted, and this is the desired buffer effect
Cannot be said to have been realized. Especially at the end of the stroke
Thrust acting on the piston in the
Is transmitted to the work through the head.

[0009]

This invention SUMMARY OF THE INVENTION In view of the above points, which has been devised to solve the problems found in the prior art, in order to achieve this object, a fluid therein
Cylinder tube to which is supplied, and the cylinder tube
The shaft is reciprocated by the supplied fluid
And the axis of the cylinder tube
Provided at each end in the direction
A stroke limiter for defining a stroke amount;
To the same direction as the ton
Protruding axially outward through the other stroke limiter
And a piston provided between the piston and the rod.
An elastic member for elastically biasing the person away from the user.
Piston touches at least one stroke limiter
In this state, the piston and the rod are axially
An actuator is provided which is movably connected to the actuator.

[0010]

In the actuator of the present invention having the above structure, when the piston and the rod move in one direction (the direction in which the rod projects from the cylinder tube), the piston first comes into contact with a stroke limiting portion such as a rod cover. Stops by reaching the forward end of the stroke
I do. When an external force acts on the rod in this state, the piston
While the rod is stopped, only the rod pushes the elastic member
Retreat.

When the rod abuts on the workpiece during its advance and stops, the piston continues to advance independently while pressing and contracting the elastic member . If the rod abuts on the stroke limiter during the independent advance, it no longer acts on the piston. The resulting thrust is not transmitted to the rod and is not transmitted to the work. Therefore, when the work is at a position within a certain range, the buffer effect by the elastic member can be reliably realized.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

As shown in FIG. 1, a through hole 6
The rod 3 is inserted into the through hole 6 slidably in the axial direction with its rear end (right end in the drawing), and a step 7 is formed on the peripheral surface of the rod 3. A coiled spring 10 which is an elastic member is mounted in a compressed state between a spring receiver 8 engaged with the spring 7 and a spring receiver 9 backed up by the piston 2, and this rod is attached to the rear end of the rod 3. A stopper 11 is provided to prevent 3 from falling out of piston 2.

The piston 2 and the rod 3
The spring receiver 8, from the position where
The members 9 are relatively movable in the axial direction up to the position where they contact each other. Reference numeral 12 denotes a packing, 13 denotes a bearing, 1 denotes a cylinder tube, 14 denotes a head cover which is a stroke restricting portion in a retreating direction (right direction in the figure), and 15 denotes a stroke in a forward direction (left direction in the figure). The rod covers 16 and 17 which are the restriction portions are pressure supply ports.

When a fluid pressure such as air pressure is supplied from the state shown in FIG. 1 to the pressure supply port 16 on the right side in the figure, the piston 2 and the rod 3 simultaneously advance to the left (FIG. 2). When the distal end of the rod 3 comes into contact with, for example, a workpiece, the rod 3 and the piston 2 start to move relative to each other, and the rod 2 is stopped, and
When the advancing is continued independently while compressing and contracting, and the rod abuts on the rod cover 15 during the advancing alone, the thrust acting on the piston 2 is no longer transmitted to the rod 3 and is not transmitted to the work. Further, when an external force acts on the rod 3 in a state where both the piston 2 and the rod 3 have reached the forward end, the piston 2 remains stopped, and only the rod 3 retracts while compressing the spring 10 (FIG. 3). Therefore, in any case, the spring 10 is contracted to generate a buffering action, thereby preventing the work from being broken as in the related art.

Next, a case where the actuator has a stroke adjusting mechanism will be described.

As shown in FIG. 4, a stopper 18 having both a rod-preventing function and a spring receiving function is fixed to the rear end of the rod 3 by screwing, and an elastic member is provided between the stopper 18 and the piston 2. Is mounted in a compressed state. The stopper 18, the rod 3, and the piston 2 are assembled by an outer cover 19, which is a part of the piston 2, which is fixed to the piston 2 by screwing. The outer cover 19 is provided with a vent hole 20. The rod 3 is slidable in the axial direction with respect to the outer cover 19.

Reference numeral 21 denotes a stroke adjusting mechanism for adjusting the forward / stop positions of the piston 2 and the rod 3;
A rod member 22 fixed to the piston 2 by screwing;
A stopper member 23 screwed to the rod member 22 and a lock nut 24 are provided. When the stopper member 23 contacts the head cover 14 during forward movement, the forward stop position of the piston 2 and the rod 3 is specified. It is supposed to. The adjustment is performed by changing the mounting position of the stopper member 23 with respect to the rod member 22. Reference numeral 12 is packing, 13 is a bearing,
1 is a cylinder tube, 15 is a rod cover, and 16 and 17 are pressure supply ports.

When a fluid pressure such as air pressure is supplied from the state of FIG. 4 to the pressure supply port 16 on the right side in the figure, the piston 2, the rod 3, and the stroke adjusting mechanism 21 simultaneously advance leftward (FIG. 5). When the distal end of the rod 3 comes into contact with, for example, the workpiece during the forward movement, the rod 3 and the piston 2 start to move relative to each other, and when the rod 3 is stopped, the piston 2 and the stroke adjusting mechanism 21
0 while pushing forward, the piston 2 abuts on the rod cover 15 during this forward movement.
Is not transmitted to the rod 3 and is not transmitted to the work. When an external force acts on the rod 3 in a state where the piston 2, the rod 3, and the stroke adjusting mechanism 21 have all reached the forward end, the piston 2 and the stroke adjusting mechanism 21 remain stopped, and only the rod 3 To retract while compressing (FIG. 6). Therefore, in any case in the actuator, the buffering action is generated by the contraction of the spring 10, and it is possible to prevent the work from being broken as in the related art.

If the vent hole 20 is omitted from the actuator shown in FIGS. 4 to 6, a hollow material can be used for one or both of the rod 3 and the rod member 22, as shown in FIG. . The buffer structure shown in FIG. 4 can be used for a single rod actuator as shown in FIG.

[0021]

[Effects of the Invention] The present invention has the following effects.

[0022] In the actuator Sunawa Chi present invention, the piston and rod are unidirectional (rod cylinder
(To project from the tube)
The stone contacts the stroke limiting part such as the rod cover
To reach the forward end of the stroke and stop
You. In this state, apply the rod or rod end
When an external force acts on the workpiece, the piston remains stopped.
Only the rod retracts while compressing the elastic member. did
As a result, the elastic member is compressed and compressed,
Work occurs and the workpiece is broken by external force as in the prior art.
It can be prevented from being lost.

When the rod abuts on the workpiece during its forward movement and stops, the piston continues to advance independently while compressing and compressing the elastic member. The resulting thrust is not transmitted to the rod and is not transmitted to the work. Therefore, when the work is at a position within a certain range, the buffering effect of the elastic member can be reliably realized, thereby preventing the work from being broken.

[Brief description of the drawings]

FIG. 1 is a sectional view of an actuator according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing the operation of the actuator.

FIG. 3 is a sectional view showing the operation of the actuator.

FIG. 4 is a sectional view of an actuator according to a second embodiment of the present invention;

FIG. 5 is a sectional view showing the operation of the actuator.

FIG. 6 is a sectional view showing the operation of the actuator.

FIG. 7 is a cross-sectional view of an actuator according to a third embodiment of the present invention.

FIG. 8 is a sectional view of an actuator according to a fourth embodiment of the present invention.

FIG. 9 is a sectional view of an actuator according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder tube 2 Piston 3 Rod 4 Tightening member 5 Spacer 6 Through hole 7 Step 8, 9 Spring receiver 10 Spring (elastic member) 11, 18 Stopper 12 Packing 13 Bearing 14 Head cover (Stroke limiting part) 15 Rod cover (Stroke limiting) 16, 17 Pressure supply port 19 External cover 20 Vent hole 21 Stroke adjusting mechanism 22 Rod member 23 Stopper member 24 Lock nut

Claims (1)

(57) [Scope of request for utility model registration] 1. A cylinder tube to which a fluid is supplied.
(1) and housed in the cylinder tube (1),
Reciprocally move in the axial direction by the supplied fluid
Piston (2) and axial direction of the cylinder tube (1)
And the piston (2) is in contact with
A stroke limiter (14,
15) and the same as the piston (2) reciprocates.
To at least one of the stroke limiters (1
Rods (3) projecting axially outwardly through 4, 15)
And provided between the piston (2) and the rod (3).
And an elastic member (1
0), wherein said piston (2) has at least one stroke limit
In contact with the parts (14, 15), the piston
(2) and the rod (3) are relatively movable in the axial direction.
An actuator, wherein the actuator is connected .