JPH0124403Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an air cylinder having a reciprocating motion control device, and more specifically, to an air cylinder having a structure in which a control valve, a limit valve, etc. for controlling reciprocating motion are integrally provided in the cylinder.

First, a conventional example of a reciprocating motion control device for controlling the reciprocating motion of an air cylinder will be explained, and its problems will also be mentioned.

FIG. 1 is a circuit diagram showing a conventional example of a reciprocating motion control device.

The reciprocating motion control device includes a switch valve 1, limit valves 2 and 3, and a control valve 4, and controls the reciprocating motion of a single air cylinder 6.

A pressure source is connected to the input of switch valve 1 by line 100, the out port of switch valve 1 is connected to the input of limit valve 2 by lines 101 and 103, and the input of control valve 4 by lines 101 and 102, The out port of the control valve 4 is connected to the import port of the limit valve 3 by lines 104 and 105, and the pilot port of the control valve 4 by lines 104 and 106, and the two out ports of the control valve 4 are connected to the line 107 and 108.
are connected to the rod side and head side ports of the air cylinder 6, respectively.

When the switch valve 1 is turned on, air pressure from the pressure source is supplied to the input of the control valve 4 and the input of the limit valve 2. The air pressure supplied to the control valve 4 is supplied to the rod side of the air cylinder 6,
The piston 61 is moved to the head side, the air pressure in the head side space is exhausted through the control valve 4, and the limit valve 2 is switched by a cam provided at the tip of the piston rod 62.

When limit valve 2 is switched, limit valve 2
The air pressure being supplied to the control valve 4 is supplied to the pilot port of the control valve 4 to switch the control valve 4. When the control valve 4 is switched, the air pressure supplied to the control valve 4 is supplied to the head side of the air cylinder 6, moving the piston 61 toward the rod side, and the air pressure in the rod side space is exhausted through the control valve 4. At the same time, the limit valve 3 is switched by a cam provided at the tip of the piston rod 62. At this time, the limit valve 2 is returned by the spring.

When the limit valve 3 is switched, the air pressure in the pilot port of the control valve 4 is exhausted through the limit valve 3, so that the control valve 4 is returned by the spring.

Such a reciprocating motion control device has the following problems.

First, the conventional reciprocating motion control device has a switch valve 1,
Since the limit valves 2, 3 and the control valve 4 are separately connected to a single air cylinder 6, parts for attaching each of the valves and piping for connecting each of the valves to each other are required. For this reason, installation and piping work are costly and time consuming, and the overall structure of the device becomes large, which in turn results in a loss of air pressure.

Also, when the piston 61 in the air cylinder 6 reaches the end of the cushion stroke on the head and rod sides, the air pressure remaining in the air spaces on the head and rod sides causes the limit valves 2 and 3 to slowly loosen at a low speed. As a result, switching of the control valve 4 becomes uncertain, and the control valve 4 stops in a neutral state, causing the cylinder 6 to stop operating and reciprocating motion control to be impossible.

Furthermore, when the switch valve 1 is turned off, the air pressure at the pilot port of the control valve 4 is increased to the line 106.
As a result, when the switch valve 1 is turned on during startup, the control valve 4 may malfunction or the piston rod 6 may
There was an inconvenience that 2 would pop out.

The purpose of the present invention is to provide the first and second limit valves and control valves constituting the reciprocating motion control device integrally in an air cylinder to reduce the size of the air cylinder, and to provide an exhaust groove in the cushion ring of the piston rod to control the cushion stroke. It has a reciprocating motion control device that ensures the switching operation of the first and second limit valves at the terminal end, and further provides a check valve on the control valve to ensure that the control valve returns at the end of the operation. Our purpose is to provide air cylinders.

To achieve the above object, the air cylinder having a reciprocating motion control device according to the present invention has a reciprocating motion control device that controls reciprocating motion with a reciprocating motion control device connected to a switch valve that selects a pressure source and the atmosphere. In the air cylinder, the reciprocating motion control device includes a first limit valve, a second limit valve whose out port is open to the atmosphere, a control valve consisting of a switching valve having one spring-biased pilot port, and a check valve. The out port of the switch valve is connected to the in port of the first limit valve, the in port of the control valve, and the out port of the check valve, and the out port of the first limit valve is connected to the out port of the second limit valve. is connected to the input port of the control valve, the pilot port of the control valve, and the import port of the check valve, and the two outports of the control valve are connected to the head side port and rod side port of the cylinder, respectively, and the cylinder is connected to the cylinder tube port. , a head cap, a rod cap, a piston, a piston rod, a head-side cushion ring, and a rod-side cushion ring, and both ends of the cylinder tube are sealed with the head cap and the rod cap,
A head-side cushion ring and a rod-side cushion ring are provided on both sides of the piston rod of the piston inserted into the cylinder tube, and the head cap is provided with the control valve, the check valve, and the first limit valve. is,
The rod cap is provided with the second limit valve, and the head side and rod side cushion rings are provided with a limit valve for exhausting the residual air pressure in the cylinder when the piston reaches the end of the cushion stroke on the head side and rod side. Provide an exhaust groove to
When the piston moves to the head side by switching the control valve, after passing through the cushion stroke, the first limit valve is operated while exhausting the residual air in the head side space using the exhaust groove of the cushion ring on the head side. The piston is opened and the control valve is switched by the first limit valve, the piston is moved to the rod side, and after a cushion stroke, the remaining air in the rod side space is exhausted through the exhaust groove of the cushion ring on the rod side. When the second limit valve is opened and the switch valve is closed, residual air pressure in the pilot port of the control valve is exhausted by the check valve, and the control valve is reset.

According to the above structure, the object of the present invention can be completely achieved.

Hereinafter, the present invention will be explained in more detail with reference to the drawings and the like.

FIG. 2 is a circuit diagram showing an embodiment of an air cylinder having a reciprocating motion control device according to the present invention, and FIG. 3 is a configuration diagram showing an embodiment of an air cylinder having a reciprocating motion control device according to the present invention. Note that parts having the same functions as those in the conventional example described above are given the same reference numerals.

In FIG. 2, 1 is a switch valve, 2 and 3 are limit valves, 4 is a control valve, 5 is a check valve, and 6 is an air cylinder. The part surrounded by the chain line is the part included in the air cylinder according to the present invention.

A pressure source is connected to the input port of the switch valve 1 by a line 100, and the out port of the switch valve 1 is connected to the import port of the limit valve 2 by lines 101, 103,
102a imports control valve 4, line 1
02,109 to the out port of the check valve 5. The out port of limit valve 2 is connected to the limit valve 3 through lines 104 and 105, and the control valve 4 is connected through lines 104 and 106.
The pilot port of the check valve 5 is connected by lines 104 and 110 to the input of the check valve 5.
The two out ports of control valve 4 are connected to line 107,
It is connected to the rod side port and the head side port of the air cylinder 6 by 108, respectively. The pilot shafts 21, 31 of the limit valves 2, 3 are switched when the piston 61 reaches its end on the head side and the end on the rod side.

In Fig. 3, 61 is the piston rod, 62
is a piston, 63 is a head cap, 64 is a rod cap, 65 and 66 are cushion rings, 6
7 and 68 are cushion packings, and 69 is a cylinder tube. The head cap 63 is integrally provided with a limit valve 2, a control valve 4, and a check valve 5, and the rod cap 64 is provided with a limit valve 3.

The head cap 63 is provided with an import IN for the air cylinder 6, and passages 101, 10
2 to the air space of the main shaft 40 of the control valve 4. The control valve 4 includes main shafts 40, 45, poppet valves 41, 42, 46, 47, and springs 43, 4.
8. Pilot ends 40a, 45 of main shafts 40, 45
It is composed of a. The air space of the main shaft 40 is connected to the air cylinder 6 through a passage 107a, a bypass pipe 71, and a passage 107b of the rod cap 64.
It is connected to the rod side space.

On the other hand, the import IN is connected to the import of the limit valve 2 by a passage 103 branched from the passage 101. Limit valve 2 is pilot shaft 2
1, a poppet 22, and a spring 23. Out port of limit valve 2 is passage 1
04, bypass pipe 72, rod cap 64
is connected to the inlet of the limit valve 3 via a passage 105. The limit valve 3 is composed of a pilot shaft 31, a poppet 32, and a spring 33. The out port of the limit valve 3 is connected to the atmosphere by a passage 112.

In addition, import IN is aisle 101, 102,
It is connected to the out port of the check valve 5 by a passage 109, and the in port of the check valve 5 is connected to the pilot port of the control valve 4 by a passage 110. The check valve 5 has a ball 51 and a spring 52.
It is composed of. The head side space of the air cylinder 6 is connected to the air space of the main shaft 45 of the control valve 4 through a passage 108, and the air space of the main shaft 45 is connected to the exhaust port EXH of the air cylinder 6 through a passage 113.
connected to the atmosphere. Speed controllers 75 and 76 are provided at the exhaust port EXH.

Cushion rings 65 and 66 are provided at both ends of the piston 62 of the piston rod 61.
These cushion rings 65 and 66 have exhaust grooves 65.
a, 66a are provided. The exhaust groove 65a is for bypassing the residual air pressure in the head side space and exhausting it to the passage 108 side when the piston rod 61 reaches the end of the head side cushion stroke. Similarly, the exhaust groove 66a is for bypassing the residual air pressure in the rod side space and exhausting it to the passage 107b side when the piston rod 61 reaches the end of the rod side cushion stroke.

Next, the operation of the air cylinder having the reciprocating motion control device according to the present invention will be explained.

When the switch valve 1 is turned on, air pressure is supplied from the import IN of the air cylinder 6, and the passage 10
1, 102 to the air space of the main shaft 41 of the control valve 4, a passage 103 to the inlet of the limit valve 2, and a passage 109 to the outport of the check valve 5.

Since the main shaft 40 of the control valve 4 is moved to the right by the spring 43, the valve 41 is closed and the valve 42 is open. Therefore, the air pressure is in the passage 107a,
The air is supplied from the bypass pipe 71 and the passage 107b to the rod side space of the air cylinder 6, and the piston 62
Move it to the head side.

The piston 62 moves to the head side, and the tip of the cushion ring 65 touches the cushion ring gasket 6.
When the cylinder reaches position 7 and enters the so-called cushioning stroke, the air pressure remaining in the head side space passes through the passage 114 and is released into the passage 10 via the cushion needle 74.
8, the moving speed of the piston rod 61 becomes slow. Further, the piston rod 61 moves, and the tip of the exhaust groove 65a provided in the cushion ring 65 moves to the cushion ring gasket 67.
The residual air pressure in the head side space is at passage 10.
Temporarily exhausted to the 8 side. At this time, the piston 62 speeds up slightly at the end of the cushion stroke, the head side of the piston 62 pushes the pilot shaft 21 of the limit valve 2, and resists the biasing force of the spring 23 to surely open the poppet 22.

When the poppet 22 opens, the air pressure being supplied to the limit valve 2 is supplied from the out port through the passage 104, the bypass pipe 72, and the passage 105 to the input of the limit valve 3, and
6 to the pilot port of the control valve 4, and the pilot ends 40a, 45 of the main shafts 40, 45.
Press a and move the main shafts 40, 45 to the springs 43, 48.
switch against the urging force of.

When the main shaft 45 of the control valve 4 is switched, the valve 47 closes and the valve 46 opens, so the air cylinder 6 is not imported.
Air pressure from IN is supplied to the head side space of the air cylinder 6 through the passage 108.

The piston 62 moves to the rod side, and the tip of the cushion ring 66 touches the cushion ring gasket 6.
When the rod reaches the position 8 and enters the so-called cushioning stroke, the air pressure remaining in the rod side space passes through the passage 115 and enters the passage 10 via the cushion needle 73.
7b, the moving speed of the piston rod 61 becomes slow. Furthermore, the piston rod 61
moves, and the tip of the exhaust groove 66a provided in the cushion ring 66 touches the cushion ring gasket 6.
When exiting from 8, the residual air pressure in the rod side space is in passage 1.
It is temporarily exhausted to the 07b side. At this time, the piston 62 speeds up slightly at the end of the cushion stroke, and the rod side of the piston 62 pushes the pilot shaft 31 of the limit valve 3, resisting the biasing force of the spring 33 and opening the poppet 32 reliably.

When the poppet 32 opens, the air pressure being supplied to the limit valve 3 is exhausted from the out port through the passage 112. When the limit valve 3 is opened, the air pressure in the passage 105, bypass pipe 72, passage 104, and passage 106 is exhausted, so that no air pressure is supplied to the pilot port of the control valve 4, and the main shafts 40, 45 are connected to the spring 43, It returns by the urging force of 48. At this time, the air pressure in the rod side space is
The air is exhausted through the air space of the main shaft 40 through the air space 07a, through the passage 113, and from the exhaust port EXH.

Thereafter, this operation is repeated and the air cylinder 6 is controlled to reciprocate. When stopping the reciprocating movement of the air cylinder 6, the switch valve 1 is turned off. When the switch valve 1 is turned off, the passage 104,
The air pressure in 105, 110 passes through the check valve 5, passages 109, 102, 101, and the switch valve 1.
is exhausted from the exhaust port.

FIGS. 4 and 5 are diagrams showing more specifically an embodiment of the reciprocating motion control device according to the present invention. Fourth
The figure mainly shows the limit valve 2, the limit valve 3, and the exhaust grooves 65a, 66a of the cushion rings 65, 66 provided on the piston rod 61. The reference numerals of other parts are the parts having the same functions as the parts with the same reference numerals in the configuration diagram of FIG. Fifth
The figure shows details of the check valve 5 within the control valve 4.

As explained in detail above, according to the present invention,
Since the first and second limit valves and control valves constituting the reciprocating motion control device are integrally provided in the air cylinder, the overall size is reduced.

Further, since an exhaust groove is provided in the cushion ring of the piston rod to exhaust the residual air pressure in the cylinder at the end of the cushion stroke, the switching operation of the first and second limit valves becomes reliable.

Furthermore, the control valve is provided with a check valve. This allows the pilot pressure to be completely released via the check valve 5 when the switch valve 1 is turned off. As a result, the control valve is reliably returned to its original position at the end of operation, which eliminates malfunctions during startup, and eliminates piston rod popping out.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing a conventional example of a reciprocating motion control device. FIG. 2 is a circuit diagram showing an embodiment of an air cylinder having a reciprocating motion control device according to the present invention, and FIG. 3 is a configuration diagram showing an embodiment of an air cylinder having a reciprocating motion control device according to the present invention. Fourth
FIG. 5 is a diagram showing more specifically an embodiment of the reciprocating motion control device according to the present invention. 1...Switch valve, 2, 3...Limit valve, 2
1, 31... Pilot shaft, 22, 32... Poppet, 23, 33... Spring, 4... Control valve, 40, 45... Main shaft, 40a, 45a... Pilot end, 41, 42, 46, 47 ... Poppet valve, 43, 48 ... Spring, 5 ... Check valve, 6 ... Air cylinder, 61 ... Piston rod, 62 ... Piston, 63 ... Head cap, 64 ... Rod cap, 65 ... Head side shoe. Shion ring, 66... Rod side cushion ring, 65a, 66a... Exhaust groove, 67, 68
...Cushion ring patchkin.

Claims (1)

[Scope of utility model registration request] In an air cylinder having a reciprocating motion control device that controls reciprocating motion with a reciprocating motion control device connected to a switch valve that selects a pressure source and the atmosphere, the reciprocating motion control device has a first limit valve, and an out port is connected to the atmosphere. a second limit valve that is open to the first limit valve, a control valve consisting of a switching valve having one spring-biased pilot port, and a check valve, the out port of the switch valve being open to the input of the first limit valve; an inlet of a valve, an outport of the first limit valve is connected to an inlet of the second limit valve, a pilot port of the control valve, an inlet of the check valve; Control valve 2
two out ports are respectively connected to a head side port and a rod side port of the cylinder, and the cylinder includes a cylinder tube, a head cap, a rod cap, a piston, a piston rod, a head side cushion ring, and a rod side cushion ring, Both ends of the cylinder tube are sealed with the head cap and the rod cap, and a head side cushion ring and a rod side cushion ring are provided on both sides of the piston rod of the piston inserted into the cylinder tube, and the head cap is provided with a head side cushion ring and a rod side cushion ring. A control valve, the check valve, and the first limit valve are provided, the rod cap is provided with the second limit valve, and the cushion rings on the head side and the rod side are provided with the piston on the head side and the rod side. An exhaust groove is provided to exhaust the residual air pressure in the cylinder when the end of the cushion stroke on the side is reached, and when the piston moves to the head side by switching the control valve, the shoe on the head side is While exhausting the residual air in the head side space through the exhaust groove of the cushion ring, the first limit valve is opened and the control valve is switched by the first limit valve to move the piston toward the rod side, thereby starting the cushion stroke. After that, the second limit valve is opened while exhausting the remaining air in the rod-side space through the exhaust groove of the rod-side cushion ring, and when the switch valve is closed, the control valve is opened by the check valve. 1. An air cylinder having a reciprocating motion control device, characterized in that the control valve is reset by exhausting residual air pressure in a pilot port.