JPH0527682Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a pressure intensifier circuit that increases the pressure of low-pressure air and outputs it, and more specifically relates to a pressure intensifier circuit suitable for driving a fluid pressure actuator. It is something.

[Prior art] Recently, there has been a tendency to lower the set pressure of compressors in order to save energy, but lowering the set pressure of compressors causes distortion at the line air terminals such as insufficient output and longer takt times. Occur.

Therefore, a pressure increase device that increases the pressure of low-pressure air and outputs it was proposed in Japanese Utility Model Application Publication No. 144203/1983 and others.
The actuator is driven by high-pressure air boosted by this pressure booster.

Conventionally, when an actuator is driven by high-pressure air pressurized by a pressure booster, as shown in FIG. A pressure intensifier circuit connected by

In addition, when the actuator 2 works only in the drive stroke and does not work in the return stroke, low-pressure air can be supplied from the solenoid valve 3 to the return side of the actuator 2, as shown in FIG. 4B. is possible. Note that reference numeral 5 in FIGS. 4A and 4B is a speed controller that controls the speed of the actuator 2 by meter-out.

The pressure booster circuits shown in FIGS. 4A and 4B can drive the actuator 2 with the high pressure air boosted by the pressure booster 1 without causing a lack of output, etc. However, these pressure booster circuits Since the high-pressure air boosted by the pressure booster 1 passes through the solenoid valve 3, the solenoid valve needs to be robust enough to withstand high pressure, which causes the problem that the circuit becomes expensive.

In addition, a pressure booster circuit equipped with a solenoid valve that switches between low pressure air and high pressure air boosted by a pressure booster and outputs the output by energizing and releasing a solenoid was proposed in Japanese Utility Model Application Publication No. 189801/1983. ing.

In this previously proposed pressure booster circuit, when high-pressure air is supplied, the high-pressure air boosted by the pressure booster does not pass through the cylinder drive circuit (usually an electromagnetic switching valve), but when high-pressure air is discharged, the above-mentioned drive circuit In order to pass through
Since this drive circuit needs to be able to withstand the high air pressure that is discharged, it cannot be made sufficiently strong and inexpensive to withstand the low air pressure.

In addition, switching between high and low pressure air is performed using a solenoid valve, which increases costs due to the solenoid.
Since another means for linking the switching of the cylinder drive circuit and the switching of the electromagnetic valve is required, it is not possible to expect a reduction in the cost of the pressure booster circuit.

[Problem to be solved by the invention] The problem to be solved by the invention is to provide a pressure booster circuit that can be made inexpensive.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a pressure booster circuit including a supply port communicating with a low pressure air source, two output ports, and a discharge port communicating with outside air, a solenoid valve that switches the output port to a position communicating with the supply port or the discharge port; an input port communicating with the low-pressure air source; an output port for pressurized air;
It is equipped with a pressure boosting chamber and a drive chamber that communicate with the input and output ports via an inlet check valve and an outlet check valve, and a piston is driven by supplying and discharging low-pressure air to the drive chamber using a switching valve. a pressure booster that increases the pressure of the supplied low-pressure air in a pressure booster chamber and outputs it from an output port; a first input port that communicates with the output port of the pressure booster; and a first input port that communicates with one of the output ports of the solenoid valve. It has two input ports and an output opening, and is driven by fluid pressure supplied and discharged from the solenoid valve to a pressure chamber communicating with the second input port, and the output opening is located at a position communicating with the first input port and the aperture. It is characterized by comprising a select valve that switches to a position that communicates with the second input port when the input port is in the state of communication with the second input port.

[Function] When the solenoid valve is in the switching position where one of the output ports communicates with the discharge port, and the other of the supply port and the output port communicate with each other, the select valve
Because it communicates with the outside air through the input port and solenoid valve,
The output aperture communicates with outside air through the second input port which is in a throttled state and the first input port is blocked.

When the solenoid valve is switched to a position where one of the supply port and the output port communicates with the other output port and the discharge port, low pressure air is supplied to the pressure chamber of the select valve, and the select valve connects the first input port and the output port. Since the opening is switched to a position where it is communicated and the second input port is blocked, high-pressure air increased by the pressure increasing device is outputted from the output opening.

When the solenoid valve is switched to its original position, the pressure chamber communicates with the outside air via the solenoid valve, the select valve returns to its original switching position, and the output opening communicates with the throttled second input port. , the exhaust gas is depressurized and discharged from the solenoid valve.

Therefore, the solenoid valve can be made durable and inexpensive enough to withstand low air pressure.

In addition, since the select valve is automatically switched when the solenoid valve supplies and discharges low-pressure air to the pressure chamber, there is no need to provide separate means to operate these valves in conjunction with each other. In combination with the fact that the voltage can be made more comfortable and that no solenoid is used, the pressure increase circuit can be made inexpensive.

[Embodiment] FIGS. 1 to 3A and 3B show an embodiment of the present invention, and this pressure increase circuit includes a solenoid valve 11, a pressure increase device 1
2, and a select valve 13.

As schematically shown in FIG. 1, the solenoid valve 11 includes a supply port P that communicates with a low-pressure fluid source, two output ports A and B, and two discharge ports EA and EB. It is composed of a well-known 5-port valve in which ports P and A and B and EB communicate with each other, and when the solenoid is de-energized, the valve is switched to a position where ports P and B and A and EA communicate with each other.

As schematically shown in FIG. 3A, the pressure booster 12 includes a main body block 17 having an input port 15 communicating with a low-pressure air source and an output port 16 communicating with a select valve, and a pair of cylinders 18 sandwiching the main body block 17. Pistons 19, 19 sliding inside 18 are connected to the main body block 1.
7 are connected by a rod 20 which is passed through airtightly,
The pressure increasing chambers 21, 21 inside the pistons 19, 19 are connected to the inlet check valves 22, 22 and the outlet check valve 2.
3, 23 to the input port and output port 15, 1
6, and is constructed as a double-acting type in which low pressure air is alternately supplied and discharged to and from drive chambers 24, 24 on the outside of the pistons 19, 19 by means of a switching valve 25 which is interlocked with the drive of the pistons.

However, the pressure booster 12 is not limited to the double-acting type, and as schematically shown in FIG. The cylinder 18
It is also possible to adopt a single-acting type in which a is divided into a pressure increasing chamber 21 and a driving chamber 24.

The select valve 13, whose details are shown in FIG. and an output opening 33 are opened, and the sleeve 34 inserted into the axial hole communicating these openings has these openings 3.
1, 32, and 33 have separate openings that communicate with each other.

A pressure chamber 37 is defined at one end of the hole by a pilot piston 36 slidably inserted into the hole, and the pressure chamber 37 is connected to the second input port 32 by a pilot passage 38. is connected to. Furthermore, the spool 39 sliding inside the sleeve 34 moves the output opening 33 to the input port depending on the magnitude of the fluid pressure in the pressure chamber 37 and the biasing force of the return spring 40 contracted on the opposite side of the pressure chamber 37. 31 or 32
Switch to a position that communicates with

The valve body 30 is provided with a cylindrical member 42 that opens into the pressure chamber 37 in the axial direction of the spool 39, and a needle 43 slidably inserted into the member 42 projects outside the member 42. A handle 44 fixed to the bent end is screwed onto the member 42, and can be moved forward and backward relative to the member 42 by rotating the handle 44. Therefore, by moving the needle 43 back and forth to adjust the sliding distance of the spool 39, the opening degree of the second input port 32 by the land 39a can be adjusted.

Reference numeral 50 in FIG. 1 indicates an actuator, a drive chamber 50a of the actuator 50 communicates with the output opening 33 of the select valve 12, and a return chamber 50b.
It communicates with the output port B of the solenoid valve 11 via the speed controller 51.

Next, with reference to FIG. 1, a case will be described in which the actuator is driven by the above embodiment.

In FIG. 1, when the solenoid 11a is de-energized, ports P and B and A and EA of the solenoid valve 11 communicate with each other, and fluid pressure is supplied to the return chamber 50b, while the pressure chamber 37 of the select valve 13 is Since it communicates with the outside air via the input port 32 and the solenoid valve 11,
The output opening 33 of the spool 39 communicates with the second input port 32 in a constricted state due to the biasing force of the return spring 40, and the fluid in the drive chamber 50a is discharged to the outside. Furthermore, since the first input port 31 of the select valve 13 is blocked, the supply of high-pressure air by the pressure booster 12 is stopped.

In this state, when the solenoid 11a is excited and the solenoid valve 11 is switched to a position where ports P and A and B and EB communicate with each other, low pressure air is supplied to the pressure chamber 37 through the second input port 32 of the select valve 13. As a result, the spool 39 is switched to a position where the output opening 33 and the first input port 31 are communicated with each other, and the second input port 32 is blocked.

Therefore, the high pressure air increased by the pressure increaser 12 is supplied to the drive chamber 50a of the actuator through the select valve 13, while the return chamber 50b is communicated with the outside air by the solenoid valve 11, so that the actuator It is driven by meter-out control by the speed controller 51.

When the solenoid 11a is de-energized, the low pressure air in the pressure chamber 37 is discharged to the outside air via the solenoid valve 11, so the spool 39 is connected to the output opening 33 and the second
The input port 32 communicates with the first input port 3 in a constricted state.
1 is switched to the position where it is cut off. Therefore, the actuator 50 passes through the solenoid valve 11 to the return chamber 5.
It returns with the low-pressure fluid supplied to 1b, and the return speed is meter-out controlled by the throttle formed by the land 39a of the spool 39. In this case, needle 4
Of course, the aperture opening degree can be adjusted as appropriate by moving 3 forward and backward.

In addition, by providing branch pipes 52a, 52b, .
High-pressure air can be supplied to a plurality of select valves using a single pressure booster 11.

[Effects of the invention] The pressure booster circuit of the present invention outputs high-pressure air that has been boosted by the pressure booster, so even when the supply fluid pressure is low, problems such as insufficient output and long takt time can be prevented. be able to.

In addition, by setting the pressure booster and the solenoid valve in parallel between the low pressure air and the input side of the select valve, the high pressure air increased by the pressure booster does not pass through the solenoid valve, so the solenoid valve can be set to low pressure. Not only can the solenoid be made durable and inexpensive, but also the solenoid can be made small and inexpensive.

Furthermore, by using a select valve driven by the fluid pressure supplied and discharged from the solenoid valve to the pressure chamber as the valve for supplying and discharging high-pressure air, another means for linking the switching of the solenoid valve and the switching of the select valve is provided. Since there is no need to provide a pressure booster circuit that can use a sophisticated solenoid valve, it is possible to make the pressure booster circuit even cheaper.

[Brief explanation of the drawing]

1 to 3 A and B show embodiments of the present invention, FIG. 1 is a symbol diagram showing the operating state, and FIG.
The figure is a longitudinal front view of the select valve, Figures 3A and B are schematic explanatory diagrams of the pressure booster, Figure 4A is a symbol diagram of a conventional pressure booster circuit, and Figure 4B works only in the drive stroke. FIG. 3 is a symbol diagram of a pressure booster circuit. 11... Solenoid valve, 12... Pressure booster, 13...
Select valve, 15...input port, 16...output port,
19, 19a... Piston, 21... Pressure boosting chamber, 2
2...Inlet check valve, 23...Outlet check valve, 24...Drive chamber, 25...Switching valve, 31...
1st input port, 32...2nd input port, 33...outlet opening, 37...pressure chamber, P...supply port, A,
B...Output port, EA, EB...Exhaust port.

Claims (1)

[Claims for Utility Model Registration] A supply port communicating with a low-pressure air source, two output ports, and an exhaust port communicating with outside air,
A solenoid valve that switches the output port to a position communicating with the supply port or the discharge port, an input port communicating with the low pressure air source, an output port for boosted air, an inlet check valve, and an outlet check valve, It is equipped with a pressure boosting chamber communicating with the output port and a drive chamber, and the piston is driven by supplying and discharging low pressure air to the drive chamber using a switching valve, and the pressure of the low pressure air supplied from the input port is increased in the pressure boosting chamber. a pressure booster outputting from an output port; a first input port communicating with the output port of the pressure booster;
a second input port communicating with one of the output ports of the solenoid valve, and an output opening communicating with one of the output ports of the solenoid valve;
a select valve that is driven by fluid pressure supplied to and discharged from a pressure chamber communicating with the input port to switch the output opening between a position communicating with the first input port and a position communicating with the second input port in a throttled state; A booster circuit characterized by comprising: