JPS6055935B2 - Fluid pressure drive device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid pressure drive device, and more particularly to a fluid pressure drive device that operates at high speed and reliably, and is suitable as a drive device for circuits and Nitta.

Conventional fluid pressure drive devices of this type employ complex structures in order to operate reliably in response to commands and to maintain stable operating conditions.

For this reason, there was a drawback that the operating speed was sacrificed. The present invention has been made in view of the above, and its purpose is to ensure reliable and high-speed operation, and to preferentially execute the operation for one of the two types of commands. The object of the present invention is to provide a fluid pressure drive device/device that does the following.

The present invention is characterized by a first pilot valve that operates in response to a first command, a timed operation valve that operates in response to a second command, and a main control controlled by the timed operation valve. valve and
a piston whose drive direction is controlled in the drive cylinder by the main control valve; and 2, which is switched depending on the piston position in the drive cylinder and controls the main control valve.
A time-limited operation valve of a fluid pressure drive device comprising a three-position position valve is connected to a second pilot valve in the form of a two-position three-boat switching valve that operates in response to a second command, and this second pilot valve. 2 position 3, operating on high pressure fluid from the valve, first supplying a portion of that high pressure fluid to said main control valve, and then operating to cease supplying said high pressure fluid to said main control valve;
The present invention consists of a boat valve-type time difference valve, and this time-limited operation valve is inserted between the fluid pressure source and the main control valve. The present invention will be explained in detail below using the embodiments shown in FIGS. 1 to 3.

FIG. 1 is a configuration diagram showing an embodiment of the fluid pressure drive device of the present invention, and the entire structure shows a drive cylinder 100 which is a driving force generating section.
, a main control valve 1 that controls the drive direction of the drive cylinder 100, a first pilot valve 50 that fluidly controls the main control valve 1 in response to a first command, and operates in response to a second command. and a main control, a time-controlled valve 20 that fluidly controls the valve 1.
0, a position valve 3 which is switched by the movement of the piston 101 of the drive cylinder 100 and fluidly controls the main control valve 1;
00, to provide a cushioning effect at the stroke end of the drive cylinder 100, and to provide a screw. It is comprised of check valves 301, 302 for quickly starting the tank 101, and an accumulator 303 for temporarily storing high-pressure fluid.

A piston 101 is slidably inserted into the cylinder body 102 of the drive cylinder 100, and it pops! Stone 101
A backing 105 for sealing is inserted between the fluid chambers 103 and 104 on both sides. Further, cushion shaft portions 106 and 107 are provided on both sides of the piston 101, and a piston rod 108 is connected to the cushion shaft portion 107.
10, 9, 110 are the piston 1 in the cylinder body 102
The fluid chamber is provided coaxially with the piston 101, and together with the cushion shaft portions 106 and 107, a cushioning effect is provided near the stroke end of the piston 101.

Note that the fluid chambers 103 and 109 and 104 and 110 are connected via check valves 301 and 302, respectively, so that the fluid flows freely from the fluid chambers 109 and 110 to the fluid chambers 103 and 104, and the flow in the opposite direction is It is designed to prevent it. The fluid chamber 110 is connected to a fluid pressure source including an accumulator 303 through a flow path 111.
is connected to the fluid chamber 7 of the main control valve 1 through a flow path 112.
Therefore, high-pressure fluid from a fluid pressure source is constantly acting on the rod side of the piston 101, trying to drive the piston 101 toward the opposite rod side.
The fluid pressure controlled by the main control valve 1 acts on the side opposite to the rod of 01, and when the fluid pressure in the fluid chambers 103 and 109 is high pressure, it acts against the fluid pressure in the fluid chambers 104 and 110. The piston 101 is driven toward the rod side, and when the pressure is low, the piston 101 is driven toward the opposite side from the rod. In addition,
113 is a backing for sealing. The main control valve 1 is a two-position, three-boat valve of the twin poppet type, and supplies or discharges high-pressure fluid to the fluid chamber 109 of the drive cylinder 100.

Figure 2 is a detailed structural diagram of the main control valve 1. 2 is the main valve spool, which has two poppets indicated by 3 and 4.
and the valve body 5, fluid chambers 6, 7, 8 and fluid chambers 9, 10, 11 that receive pilot fluid pressure are formed. The fluid chamber 6 is connected to the tank 304 through the flow path 12, the fluid chamber 7 is connected to the fluid chamber 109 of the drive cylinder 100 through the flow path 112, and the fluid chamber 8 is connected to the fluid pressure source through the flow paths 13 and 111. It's communicating. When the spool 2 is in the state shown in FIG. 2a, the fluid chambers 7 and 8 communicate with each other, supplying high pressure fluid to the fluid chamber 109 of the drive cylinder 100, and driving the piston 101 toward the rod. If the spool 2 is on the left side as shown in Figure 2b, contrary to Figure 2a, then
Fluid chambers 6 and 7 communicate with each other, and fluid chamber 109 is connected to tank 304.
The piston 101 is driven toward the opposite rod side because the pressure fluid is discharged. In this way, the drive cylinder 10 corresponds to the position of the spool 2 of the main control valve 1.
The driving direction of the piston 101 of No. 0 is controlled. The spool 2 is controlled by the four pressure receiving end surfaces 1 provided on the spool 2.
This is done based on the magnitude relationship of the fluid pressures acting on 4a, 3a, 4a, and 15a.

These pressure receiving end surfaces are fluid chambers 9, 10, 8, 1, respectively.
1, and these fluid chambers are connected to a first pilot valve 50, a timed operation valve 200, a fluid pressure source, and a position valve 300, respectively. In addition, fluid chambers 9, 10, 8, 1
When high pressure fluid is acting on 1, the pressure receiving end surfaces 14a, 3
The forces acting on a, 4a, 15a are Fl4, F3, F4, F
When l5, F3〈F4〈Fl4〈(F4+Fl5
)<(Fl4+F3), determine the width of each pressure receiving end surface. The first pilot valve 50 is a 2-position, 3-boat valve that normally supplies high-pressure fluid to the fluid chamber 9 through a flow path 51, and has a structure that discharges this high-pressure fluid when a first command is given. It is fine as long as it is from .

For example, as shown in FIG.
2 and a first valve body 54 connected via a shaft 53;
A second valve body 56 is connected to the first valve body 54 via a spool 55, a spring 57 that always presses the second valve body 56 to the left, and a valve body 58 is formed. The fluid chamber 59B is connected to the fluid chamber 9 of the main control valve via the flow path 51.
The fluid chamber 59C communicates with the tank 304 via a channel 60, and the fluid chamber 59A communicates with the fluid chamber 8 of the main control valve 1 via, for example, a channel 73. Normally, in the state shown in the figure, the supply fluid from the fluid chamber 8 is supplied to the fluid chamber 9 of the main control valve 1 through the fluid chambers 59A, 59B1 and the flow path 51 via the flow path 73, and the first When a command is given, the valve bodies 54 and 56 are moved to the right by the drive unit 52 via the shaft 53 and the spool 55 to open the fluid chambers 59B and 59C.
are in communication, and the high pressure fluid in the fluid chamber 9 of the main control valve 1 is connected to the flow path 51.
, the tank 30 via the fluid chambers 59B, 59C1 and the flow path 60.
The structure is such that it is discharged to 4. However, since the subject of the present invention is a fluid pressure drive device that requires high-speed operation,
It must have a structure that can operate at a certain level of high speed. In particular, when high speed is required, it is preferable to use a force motor driven pilot valve, for example. The time-operated valve 200 has a flow path 207 connected to a fluid pressure source.
and a flow path 258 connected to the fluid chamber 10 of the main control valve 1.
In between, it is sufficient to have the following functions:

That is, under normal conditions, the fluid chamber 10 of the main control valve 1 is at a low pressure, and when the second command is given, high pressure fluid is promptly supplied to the fluid chamber 10, and then the piston 101 of the drive cylinder 100 moves to the position valve. Any structure may be used as long as the high-pressure fluid in the fluid chamber 10 is discharged after switching 300 and the high-pressure fluid is not supplied to the fluid chamber 10 until the second command is once turned off and the command is given again. The detailed structure of the time-controlled valve 200 is as shown in FIG.
01 and a time difference valve 251 are combined.

The second pilot valve 201 and the time difference valve 251 cooperate to control the main control valve 1 and execute the above-described operations. The second pilot valve 201 is an on/off valve, and the time difference valve 251 is a two-position three-boat valve operated by pilot pressure. The second pilot valve 201 forms fluid chambers 204 and 205 with a valve body 202 and a spool 203, and the time difference valve 20
1. Communicates with a fluid pressure source. The spool 203 is normally pushed to the left by a spring 208, and the fluid chamber 204
205. The time difference valve 251 has fluid chambers 254 and 25 formed by a valve body 252 and a spool 253.
5,256 in the form of a two-position three-boat valve.

The fluid chambers 254, 255, 256 each have a flow path 257.
, 258, 259 through the second pilot valve 201,
It communicates with the fluid chamber 10 of the main control valve 1 and the tank 304. An edge 260 is provided at one end of the spool 253, and chambers 261 and 262 are formed on both sides of the edge 260. Chamber 261 is gap 2
63, and the chamber 262 communicates with the fluid chamber 254 of the second pilot valve 201 through the flow path 206 through the throttle resistance 264, and through the flow path 266 through the throttle resistance 265. Each is in communication with a tank 304. Spool 253 is normally pushed to the left by spring 267, and fluid chambers 254 and 255 are in communication. The time-limited operation valve 200 is a second pilot valve 201 having the above-described structure.
and a time difference valve 251, the high-pressure fluid is normally cut off by the second pilot valve J2Ol, and the fluid chamber 10 of the main control valve 1 is kept at a low pressure.

When a second command is given to the second pilot valve 201, the drive unit 220 pushes the spool 203 to the right via the shaft 209, communicates the fluid chambers 204 and 205, and directs the high pressure fluid through the flow path 206. It is supplied to the time difference valve 251 via the time difference valve 251. Channel 2
The high-pressure fluid supplied to the time difference valve 251 via 06, 257 is supplied to the fluid chamber 10 of the main control valve 1 via the fluid chambers 254, 255 and the flow path 258, and at the same time is supplied to the fluid chamber 261 via the gap 263. will also be supplied. On the other hand, the high-pressure fluid supplied to the fluid chamber 262 via the throttle resistor 264 provided in the middle of the flow path 206 is discharged from the flow path 266 to the tank 304 via the throttle resistor 265 . Fluid chamber 262 at this time
The pressure is determined by the relationship between throttle resistors 264 and 265. Therefore, the spool 253 is driven by the magnitude relationship between the fluid pressure acting on both sides of the edge 260 and the force of the spring 267. At this time, the pressure in the fluid chamber 262 can be set to drive the spool 253 to the right, and by appropriately setting the gap 263, the switching time of the spool 253 can be changed within a certain range. is also possible. Therefore, the sizes of the throttle resistances 264 and 265 and the gap 263 are appropriately set so that the time difference valve 251 switches slightly later than the switching of the second pilot valve 201. When the time difference valve 251 is switched as shown in FIG. 3b, the fluid chambers 255 and 256 communicate with each other, and the main control valve 1
The high pressure fluid in fluid chamber 10 is drained to tank 304, eliminating force F3. Moreover, the second pilot valve 201
While the command is being given, high pressure fluid is being supplied to the flow path 206, so the spool 253 of the time difference valve 251 also continues to be pushed to the right. Then, once the second pilot valve 2
When the command to 01 is released, the supply of high pressure fluid to the flow path 206 is stopped, and the spools 2 and 53 are pushed back to the left by the force of the spring 267, returning to the state shown in FIG. 3a. do. That is, if the time-limited operation valve 200 is configured as shown in FIG. 3, the above-described operation can be performed. position valve 30
0 is the piston of the drive cylinder 100. When it is detected that the piston 101 is near the stroke end on the opposite rod side, high pressure fluid is supplied to the fluid chamber 11 of the main control valve 1 through the flow path 16, and when the piston 101 is far from the stroke end. , the structure is such that the high pressure fluid in the fluid chamber 11 is discharged.

Since the fluid pressure drive device of the present invention is configured as in the above-described embodiment, it operates as follows.

In FIG. 1, a flow path 1 is controlled by a main control valve 1.
When the pressure of the fluid that has entered the fluid chambers 109, 103 through 12 becomes higher than the fluid pressure in the fluid chambers 110, 104 on the opposite rod side, the fluid pressure in the fluid chambers 103, 109 increases to the fluid pressure in the fluid chambers 104, 110. When the piston 101 is driven toward the rod side against the fluid pressure and is at the end of its stroke, the fluid chamber 10 of the main control valve 1 is cut off from high-pressure fluid by the second pilot valve 201; High-pressure fluid is supplied to the fluid chamber 11 when the piston 101 is near the stroke lock on the opposite rod side, and in the above state, the high-pressure fluid is exhausted, so the fluid chambers 10 and 11 have a low pressure. Further, the fluid chamber 9 is supplied with high pressure fluid via the flow path 51 by the first pilot valve 50, and the fluid chamber 8 is supplied with high pressure fluid from a fluid pressure source, so the fluid chambers 9 and 8 are High pressure will result. Therefore, the relationship between the force acting on the spool 2, that is, the force Fl4 acting on the pressure receiving end surface 14a of the fluid chamber 9 and the force F acting on the pressure receiving end surface 4a of the fluid chamber 8 is Fl4>F4.
As a result, the spool 2 is pushed to the right, resulting in the state shown in FIG. 2a. In this state, when the first command is given to the first pilot valve 50, the first pilot valve 50
0 has a structure that discharges the high pressure fluid in the fluid chamber 9 of the main control valve 1, so when the high pressure fluid in the fluid chamber 9 is discharged, only the force F4 acts on the spool 2. Therefore, the spool 2 is pushed to the left, resulting in the state shown in Figure 2b. In this state, the high pressure fluid in the fluid chambers 103, 109 of the drive cylinder 100 is discharged, and the piston 101 is driven toward the opposite side. When the piston reaches near the stroke end on the opposite rod side, this is detected and the position valve 300 is switched, high pressure fluid is supplied to the fluid chamber 11 of the main control valve 1 via the flow path 16, and the spool 2 is connected to the fluid chamber 8. The force F acting on the pressure receiving end surface 4a of
4 and the force Fl5 acting on the pressure receiving end surface 15a of the fluid chamber 11, that is, the force F4+Fl5 pushes the fluid chamber 11 to the left. Therefore, even if the command to the first pilot valve 50 is released after the piston 101 reaches the stroke end on the opposite rod side, and high pressure fluid acts on the fluid chamber 9 of the main control valve 1, the spool The force acting on 2 is Fl4〈(F4
+Fl5) and maintains the state of being pushed to the left. In this state, the second command is issued to the second time-limited valve 200.
, the drive unit 220 of the second pilot valve 201 pushes the spool 203 to the right against the spring 208 via the shaft 209 to open the fluid chamber 2.
04 and 205 are communicated, and the high pressure fluid from the flow path 207 is passed through the fluid chambers 205 and 20 and the flow path 206 to the time difference valve 25.
Supply to 1. When high pressure fluid is supplied to the time difference valve 251, the time difference valve 251 operates as described above. That is,
Initially, the flow path 206 communicating with the chamber 262 has a restricting resistance 2
64, the fluid chamber 2 flows through the flow path 257.
The high pressure fluid guided to the fluid chamber 255 and the flow path 258
The fluid is supplied to the fluid chamber 10 of the main control valve 1 via. As a result, the force acting on spool 2 is (Fl4+F3)>(F4
+Fl, ), the spool 2 is driven to the right, high pressure fluid is supplied to the fluid chambers 103 and 109 of the drive cylinder 100, and the piston 101 is driven toward the rod side. piston 1
01 is driven and the position valve 300 is switched, the high pressure fluid in the fluid chamber 11 of the main control valve 1 is discharged, and the force pushing the spool 2 to the left becomes only F4. After this, the spool 253 of the time difference valve 251 of the timed operation valve 200 is driven to the right, so the fluid chambers 255 and 256 are communicated with each other, and the fluid chamber 10 of the main control valve 1 is connected to the flow path 258, the fluid chambers 255, 25
6, and is discharged to the tank 304 via the flow path 259,
The force acting on the spool 2 becomes Fl4>F4, and the spool 2 remains pushed to the left. Further, the first command is sent to the first pilot valve 50, and the second command is sent to the timed operation valve 2.
00 at the same time, the first command is always executed with priority no matter what state the piston 101 is in.

That is, the first command discharges high pressure fluid from the fluid chamber 9 of the main control valve 1, and the second command supplies high pressure fluid to the fluid chamber 10. Therefore, regardless of whether high-pressure fluid is acting on the fluid chamber 11 or not, the force acting on the spool 2 is F3 minus F4 (+Fl5), and the spool 2 is always pushed to the left. This is the operation of the spool 2 corresponding to the first command. These operations can be summarized in the table below. In addition, in the above table, 4 and 0 indicate normal operation, and 8 indicates first operation.
O indicates the operation in response to the second command, and after the operation 8, the state is O, and after the action O, the state 4 is obtained.

Further, 1 to 0,4'' indicates the order of operation.The fluid pressure drive device according to the present invention is configured as in the above-described embodiment and operates as described above, so that the following effects can be achieved. be.

(1) It operates reliably in response to two types of commands, the first and the second, and executes the operation in response to the first command preferentially.

(2) When the first and second commands are given at the same time, the first
Even if the first command is canceled and the second command remains, the spool 2
The force acting on the spool 2 becomes Fl4<(F4+Fl5), and the spool 2 remains pushed to the left and continues in the state corresponding to the first command. Thereafter, the second command is once canceled, and then the second command is given again, and the operation corresponding to the second command is executed. As described above, according to the present invention, there is a remarkable effect that the operation can be performed reliably and at high speed, and that the operation for one of two types of commands can be executed preferentially.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing an embodiment of the fluid pressure drive device of the present invention, Fig. 2 is a detailed structural diagram of the main control valve shown in Fig. 1, and Fig. 3 is a detailed structural diagram of the time-controlled valve shown in Fig. 1. 4 are sectional views showing the structure of the first pilot valve. 1... Main control valve, 2... Spool, 3
, 4...Poppet, 5...Valve body,
6-11... Fluid chamber, 50... First pilot valve, 51... Channel, 100...
... Drive cylinder, 101 ... Zeston, 103
, 104, 109, 110...Fluid chamber, 112
...Flow path, 200...Timed operation valve, 2
01... Second pilot valve, 202...
... Valve body, 203 ... Spool, 251.
...Time difference valve, 252...Valve body, 25
3... Spool, 300... Position valve,
303...Accumulator, 304...
·tank.

Claims (1)

[Claims] 1. A drive cylinder, a piston that slides within the drive cylinder, and a main control valve that controls the drive direction of the piston in the drive cylinder using high-pressure fluid. A spool is located in the chamber, one poppet connected to and facing the spool is arranged in a fluid chamber connected to a fluid pressure source, and the other poppet is arranged in a fluid chamber connected to a fluid discharge tank, The poppets on both sides of the spool and the outermost end connected to each poppet each form a pressure receiving end surface located in a fluid chamber, and the outermost fluid chamber of the one poppet receives high pressure in response to the position of the piston. A position valve for supplying and discharging fluid is connected, and the outermost fluid chamber of the other poppet normally supplies high pressure fluid into the drive cylinder, and the first
A first pilot valve is connected to operate the main control valve to discharge high-pressure fluid in the drive cylinder to a tank when a command is given, and the fluid pressure source and the fluid chamber on the pressure-receiving end surface of the other poppet are connected. In between, a second pilot valve in the form of a 2-position, 3-port switching valve connected to a fluid pressure source is operated with high-pressure fluid from the second pilot valve, and at the same time, a portion of the high-pressure fluid is commanded to be directly connected to the fluid. 1. A fluid pressure drive device, characterized in that a time-limited valve is connected, which is a time difference valve that supplies fluid to a chamber and then stops the supply.