JPH03288100A - Pressure control valve - Google Patents

Abstract

PURPOSE:To minimize gas leak and utilize gas effectively when the gas quantity is limited by providing a switching part, a diaphragm and a pressure sensor, and changing/controlling the pressure of a pressure chamber electrically on the basis of the detection signal of the pressure sensor. CONSTITUTION:There are provided a switching part 16 for switching a passage 13 of high or low pressure gas, a diaphragm 21 for switching the switching part 16 according to the pressure fluctuation of a pressure chamber 23a, a pressure sensor 32 for detecting the pressure of the pressure chamber 23a, and control means 28, 31 for changing/controlling the pressure of the pressure chamber 23a electrically on the basis of the detection signal of the sensor 32. The pressure of the pressure chamber 23a is thus detected by the pressure sensor 32, and on the basis of its detection signal, the pressure of the pressure chamber 23a is electrically changed/controlled to switch the switching part 16 by the operation of the diaphragm 21. The pressure control of high pressure supplied gas or low pressure sucked gas can be thereby performed with the minimum gas leak.

Description

DETAILED DESCRIPTION OF THE INVENTION: Industrial Application Field The present invention relates to a pressure control valve used to control the pressure of high-pressure supply gas or low-pressure suction gas.

2. Prior Art; As conventional pressure control valves of this type, proportional electromagnetic control valves and electropneumatic regulator control valves are known.

[Problems to be Solved by the Invention] However, in the electro-pneumatic regulator described above, the spool is slid to open and close while causing gas leakage.
Further, in the proportional electromagnetic control valve, gas is constantly ejected from the nozzle to the flapper, so there is a problem in that a large amount of gas leaks. Particularly in pressure control of high-pressure supply gas, when the pressure supply source is a cylinder, the amount of gas is limited, so preventing leakage of this gas is important.

The present invention has been made by focusing on the problems existing in the prior art, and its purpose is to minimize gas leakage, and in particular, to minimize gas leakage. To provide a pressure control valve that is effective in pressure control when the pressure supply source is a cylinder and the amount of gas is limited.

[Means for Solving the Problems] In order to achieve the above object, the pressure control valve of the present invention has an opening/closing part that opens and closes a flow path of high pressure or low pressure gas, and a pressure chamber that opens and closes according to pressure fluctuations. A diaphragm for opening and closing the pressure chamber, a pressure sensor for detecting the pressure in the pressure chamber, and a control means for electrically changing and controlling the pressure in the pressure chamber based on a detection signal from the sensor.

[Production use] In the pressure control valve configured as described above.

The pressure in the pressure chamber is detected by a pressure sensor, and the pressure in the pressure chamber is electrically changed and controlled based on the detection signal, and the opening/closing section is opened and closed by the operation of the diaphragm. Therefore,
The pressure of high-pressure supply gas or low-pressure suction gas can be controlled while minimizing gas leakage.

[Example 7] Hereinafter, a first example of the present invention will be described in detail based on FIGS. 1 to 5.

First, the outline of the dispenser device shown in FIG. 2 will be described. A tank 1 contains therein a pressurized liquid 2 such as juice, and is cooled by a cooling device (not shown).

The cylinder 3 contains carbon dioxide (hereinafter simply referred to as gas).
Pressure is supplied into the tank 1 via the pressure control valve 5 and check valve 6, and when the on-off valve 7 is opened, the pressurized fluid 2 is transferred from the tank 1 through the on-off valve 7 to a container such as a pot. 8
be pumped to.

The pressure control valve 5 is controlled to open and close by a control device 9 including a CPU (central processing unit) and memory via a D/A converter 10 and a pressure control circuit 8311, and controls the flow of gas to the pressurized liquid 2 in the tank 1. Set the amount of pressure applied. Further, the on-off valve 7 is controlled to open and close by the control device 9, and supplies the pressurized liquid 2 to the container 8.

Therefore, the configuration of the pressure control valve 5 will be described in detail based on FIG. 1. The high pressure gas flow path 13 is formed in the vertebra 12,
An air supply boat 14 and an output boat 15 are provided at both ends thereof. Flow F! ! Opening/closing part 1 for opening/closing 113
6 is connected to the valve seat 17 and the valve body 18, and is always connected to the spring 1.
It is closed due to one reason.

The cover plate 20 and the diaphragm 21 are attached to the upper surface of the vertebra 12 by a plurality of bolts 22. An upper pressure chamber 23a is formed between the cover plate 20 and the tire flamm 21, and a lower pressure chamber 23a is formed below the diaphragm 21. A chamber 23b is formed. The valve stem 24 is connected to the tire flamm 21 by a nut 25.
When the internal pressure of the upper pressure chamber 23a increases and the diaphragm 21 is moved downward, the valve body 18 of the opening/closing portion 16 is opened via the valve rod 24.

The air supply passage 26 is formed in the vertebrae 12 and the lid plate 20 so as to connect the air supply bow 14rpJ of the flow passage 13 and the upper pressure chamber 23a, and an orifice 27 for throttling is provided in the middle thereof.
is provided. The communication passage 24a is formed in the vertical direction along the center of the valve rod 24 so as to connect the output boat 15 side of the flow passage 13 and the lower pressure chamber 23b. The air supply side valve 28, which is a magnetic valve, is provided on the cover plate 20 to control the opening and closing of the air supply path 26, and opens and closes the upper pressure chamber 2 as needed.
High pressure gas is introduced into 3a to increase its internal pressure. Then, due to the increase in the internal pressure of the upper pressure chamber 23a, the valve rod 24 is lowered and the opening/closing portion 16 is opened.

The exhaust passage 29 is formed in the cover plate 20 so as to communicate the upper pressure chamber 23a with the outside, and an orifice 30 for throttling is provided in the middle of the exhaust passage 29. Exhaust side valve 31 consisting of a solenoid valve
is provided on the cover plate 20 to control the opening and closing of the exhaust W@29, and discharges the gas in the upper pressure chamber 23a to the outside to lower the internal pressure as necessary. Then, the valve stem 24 is raised due to the decrease in the internal pressure of the upper pressure chamber 23a, and the valve #-18 is raised by the spring 19, and the opening/closing part 1
6 is closed.

The pressure sensor 32 is provided on the cover plate 20, detects the internal pressure E of the upper pressure chamber 23a through the communication hole 33, and outputs a detection signal. The cover 34 is mounted on the accumulator plate 20,
It covers the air supply opening valve 28, the exhaust side valve 31, and the pressure sensor 32.

A gas exhaust path 35 is formed in the vertebra 12 so as to communicate with the output port 15 side of the flow path 13, and an exhaust boat 36 is provided at the end thereof. The opening/closing part 37 for opening and closing the discharge passage 35 is composed of a valve seat 38 and a valve body 39,
It is normally closed by a spring 40. And flow path 1
When the gas pressure on the output port 15 side of 3 becomes high, the valve body 39 of the opening/closing part 37 is opened against the spring 40, and the gas pressure in the flow path 13 is discharged from the exhaust boat 36.

Note that the diaphragm 21 is urged upward by a spring 40A.

Next, the pressure control circuit for controlling the opening and closing of the pressure control valve 5 will be described in detail based on FIG. It consists of a keyboard, etc. for manually setting the liquid supply speed, etc.
External data such as the temperature data of the liquid 2 to be pressurized and the amount of liquid to be pumped are input to the control device 9 . The control device 9 selects output ports 15 necessary for pressurizing the liquid 2 to be pressurized based on the input data.
The pressure is set as a target value and output to the D/A converter 10. The D/A converter 10 converts a signal corresponding to the input target value into an analog signal, and outputs it to the preamplifier 42 as a set voltage signal.

The preamplifier 42 subjects the set voltage signal to zero point and span adjustment, and outputs it to the deviation amplifier 43 as a reference input signal.

The deviation amplifier 43 is connected to the pressure sensor 3 in the pressure control valve 5.
2 through the amplifier 44 and the reference input signal from the previous stage amplifier 42,
As shown in Fig. 4.5, the deviation is amplified and a control deviation signal is output. Comparators 45 and 46 as comparison means compare the control deviation signal from the deviation amplifier 43 with a reference signal such as a triangular wave or sawtooth wave of approximately 50 Hz to 200 Hz output from the reference signal generator 47, and turn on the control deviation signal. - Outputs an OFF control operation signal to the air supply side valve 28 or the exhaust side valve 31 of the pressure control valve 5 via the drive circuits 48 and 49. The intake side valve 28 and the exhaust side valve 31 are controlled to open and close at a duty ratio according to the on/off period of the control operation signal.

In this case, as shown in FIGS. 4 and 5, the exhaust side valve 3
A control deviation signal that is inverted with respect to the control deviation signal input to the comparator 45 for the 28th measurement of the intake valve is input to the comparator 46 for the 1st measurement.

Now, FIG. 1 shows a state in which the valves 28 and 31 on the air supply side and exhaust side are closed, and the pressures in the upper pressure chamber 23a and the lower pressure chamber 23b are balanced in a low pressure state, and in this state, the valves 28 and 31 are closed. !
24 is in the neutral position and the upper and lower opening/closing parts 37.16 are closed. Further, at this time, the on-off valve 7 shown in FIG. 2 is also closed.

In this state, when pouring liquid into the container 8, the control device 9 opens the on-off valve 7 based on the operation of a switch on the input device 41, etc. At the same time, the control device 9 sets and outputs a target value corresponding to the optimum pressure b of the output port 15 based on data such as the pressure in the cylinder 3, the gas temperature, and the temperature of the liquid to be pressurized. This output is the D/A shown in Figure 3.
The signal is input to the deviation amplifier 43 as a reference input signal via the converter 10 and the preamplifier 42.

On the other hand, a signal at a level corresponding to the pressure value in the upper pressure chamber 23a detected by the pressure sensor 32 is fed back to the deviation amplifier 43.

The deviation amplifier 43 compares the reference input signal with the feedback signal and outputs a control deviation signal corresponding to the difference between the pressure in the upper pressure chamber 23a and its target value. This control deviation signal is input to a comparator 46 via a comparator 45 and an inversion circuit 51, respectively. In this case, for example, if the pressure in the upper pressure chamber 23a is lower than the target value, the fourth
As shown in FIG. As a deviation,
The comparator 46 on the exhaust side valve 31 side is inputted as a deviation on the closing side.

Therefore, the comparator 45 outputs a control operation signal corresponding to the deviation based on the reference signal from the reference signal generator 47, but the comparator 46 outputs no or almost no control operation signal. The opposite is true if the pressure in the boat 15 is greater than the target value. Therefore, output boat 1
The air supply side valve 28 and the exhaust side valve 31 are controlled to open and close so that the pressure of 5 is optimal, an appropriate amount of gas pressure is applied in the tank 1, and the liquid is poured into the container 8 in an appropriate state.

Then, when the switch is operated to stop the supply,
The on-off valve 7 is closed and the liquid supply is stopped.

When the air supply side valve 28 and the exhaust side valve 31 open and close, depending on various factors such as gas pressure and liquid temperature,
Alternatively, in order to prevent problems such as water hammer from occurring, the control device 9 sets an optimal target value, and both valves 28, 31
Since the data on the controlled variable is fed back and controlled to match the target value, an optimal liquid supply state can be obtained.

Furthermore, when the liquid supply is not being performed, the exhaust side valve 31 is closed to prevent gas leakage, and the gas is released to the outside only when the pressure-fed liquid supply is stopped. Since it is only the reduction of the chamber 23a, the amount of discharge is extremely small. In particular, like dispenser devices used in drinking water vending machines,
When the pressure supply source is a cylinder and the amount of gas is limited, the gas can be used effectively.

[Another Embodiment] Next, a second embodiment of the present invention will be described based on FIGS. 6 to 9. Note that the same or similar configurations as in the first embodiment are designated by the same reference numerals as in the first embodiment.
Their detailed explanation will be omitted.

Now, the pressure control valve 5 of this embodiment is embodied in the control of vacuum pressure when, for example, suction and release operations of articles are performed using vacuum pressure, and are shown in FIGS. 6 to 8. As shown in the figure, the output boat 15 of the flow path 13 is connected to a set pressure port connected to a negative pressure device such as a tank, the air supply boat 14 is connected to a vacuum pressure port connected to the suction bong 1, and the exhaust boat 36 is connected to the atmosphere. It is an atmospheric pressure port for taking in air. Air supply path 2
Reference numeral 6 is provided to communicate the lower pressure chamber 23b below the diaphragm 21 with the atmosphere.
An air supply side valve 28 for controlling the opening and closing of the valve 6 is interposed. The two exhaust passages are provided to communicate the vacuum pressure port 14 of the flow passage 13 and the lower pressure chamber 23b, and an exhaust side valve 31 for controlling the opening and closing of the exhaust passage 29 is interposed in the middle thereof. .

The pressure sensor 32 is connected to the set pressure port 15 through the communication hole 33, and is configured to detect the set pressure and output a detection signal. Further, the upper pressure chamber 23a above the diaphragm 2.1 is connected to the set pressure port 1 through the communication passage 24a at the center of the valve stem 24 and between the valve element 18 of the opening/closing part 16 and the valve stem 24.
5, and the set pressure is guided to the upper pressure chamber 23a.

As shown in FIG. 9, in this embodiment,
Almost the same as the circuit configuration of the first embodiment, the detection signal of the set pressure outputted from the pressure sensor 32 and the input signal are compared in the deviation amplifier 43 to perform deviation amplification, and this deviation signal and the reference signal generation circuit The reference signal from 47 is compared and added in the signal comparison circuit 46 via the signal comparison circuit 45 and the inversion circuit 51, and the on/off signal is sent to the air supply opening valve 28 and the exhaust side valve 31 via the drive circuit 48.49. is input.

In this way, the duty ratios of the on/off signals of the intake side valve 28 and the exhaust side valve 310 are controlled, and when a deviation exists, both valves 28 and 31 are driven to reduce the pressure in the lower pressure chamber 23b. or adjusted.

That is, a command signal from the outside is used as an input signal to control the amount F! Input to @11. The difference amplifier 43 in the control circuit 11 compares the signal detected by the sensor 32 of the pressure on the set pressure side with the input signal, and performs deviation amplification.

This deviation signal is sent to the comparator 45 and also to the inverting circuit 51.
The comparator 46 compares and adds the signal from the reference signal generation circuit 47 via the on/off signal to the drive circuit 48.
．． 49.

In this way, the duty ratio of the on/off signal of the valve 28.31 is controlled. When a deviation exists, the valve 28.31 is actuated to move the diaphragm chamber 23a in the direction of decreasing deviation;
The pressure at 23b is adjusted.

Then, the vacuum pressure is guided to the secondary side of the exhaust side valve 31 from the vacuum pressure port 14, and the operating pressure due to the on/off operation of the air supply side valve 28 and the exhaust side valve 31 is passed through the air supply path 26 and into the pilot chamber lower part 23b. Set pressure.

The primary side of the air supply side valve 28 is open to the atmosphere, and from the above, the operating pressure can range from vacuum to atmospheric pressure.

Further, the air in the set pressure boat 15 is guided to the pilot chamber upper part 23a through an orifice between the valve stem 24 and the valve body and a communication passage 24a of the valve stem 24.

When the input signal to the control circuit 11 changes and the pressure in the pilot chamber lower part 23b increases, the valve body 39 is pushed up,
Air flows from the atmospheric pressure port 36 to the set pressure port 15 .

When the input signal changes in the direction of pressure reduction from the pressure equilibrium state, the pressure in the pilot chamber lower part 23b is reduced and becomes closer to vacuum. As a result, the diaphragm 21 is pushed down, the valve body 18 is also lowered together with the valve rod 24, and air flows to the vacuum pressure port 14.

Then, when the pressures in the upper and lower pilot chambers 23a and 23b become equal, an equilibrium state is reached.

Therefore, in this second example as well, the vacuum pressure can be controlled while minimizing air leakage.

Next, a third embodiment of the present invention will be described based on FIGS. 10 to 13. Note that structures that are the same as or similar to those of the first and second actual tumor examples are given the same reference numerals as in both embodiments, and detailed explanation thereof will be omitted.

Now, similarly to the second embodiment described above, the pressure control valve 5 of this embodiment is also designed to control the vacuum pressure when vacuum pressure is used to adsorb and release an article. As shown in FIGS. 10 to 12, the set pressure port 15 of the flow path 13 is a set pressure port connected to a negative pressure device such as a tank, and the vacuum pressure port 14 is a vacuum port connected to a suction pump. A supply pressure port 36 serves as a supply pressure port for supplying a predetermined pressure of about several hf/- to the pressure port.

The switching valve 52 is provided on the roofing board 20 and has a supply pressure port 361.
1! The pressure of I is led to the switching valve 52 via the air supply path 26, the air supply side valve 28, and the output side flow path 53, and is transferred from the flow path 54 to the upper pressure chamber 23a depending on the switching state of the switching valve 52. , or supplied to the lower pressure chamber 23b via the flow path 55. The exhaust port 56.57 is provided in the switching valve 52, and depending on the switching state of the switching valve 52, the pressure in the upper pressure chamber 23a or the lower pressure chamber 23b is discharged from the exhaust port 56.57.

The exhaust side valve 31 is connected to the output side flow path 53 of the air supply side valve 28, and the output side pressure is applied to the exhaust path 2 when the exhaust side valve 31 is opened.
It is discharged through 9. The first pressure sensor 32 is connected to the communication hole 3
3 to the set pressure port 15 to detect the set pressure and output a detection signal. The second pressure sensor 58 is connected to the output side flow N53 of the intake side valve 28, detects the output side pressure, and outputs a detection signal.

As shown in FIG. 13, in this embodiment, the detection signal of the set pressure outputted from the first pressure sensor 32 and the input signal are compared in the deviation amplifier 43 to perform deviation amplification. The signal and the reference signal are compared by a comparator 59, and the switching valve 52 is switched via a drive circuit 60. Further, the deviation signal from the deviation amplifier 43 and the second
The detection signal from the pressure sensor 58 is compared and amplified by the deviation amplifier 61, and similarly to the circuit configuration of the second embodiment described above, the deviation signal and the reference signal from the reference signal generation circuit 47 are converted into a signal. The signal comparator 46 compares and adds the one on/off signal via the comparator 45 and the reversing port 8 @ 51, and the on/off signal is sent to the intake side valve 28 and the exhaust side valve 3 via the drive circuit 48 and 49.
1 is input.

In this way, if the input signal is larger than the detection signal of the first pressure sensor 32, the switching valve 52 can pressurize the lower pressure chamber 23b, and the input signal is larger than the detection signal of the first pressure sensor 32. If it is smaller, the switching valve 52 will switch to the upper pressure chamber 2.
3a is switched to a state where it can pressurize, and in this state, the duty ratios of the on/off signals of the intake side valve 28 and the exhaust side valve 31 are controlled, and when a deviation exists, both valves 28.3
1, the pressure in the upper or lower pressure chambers 23a, 23b is adjusted in a direction that reduces the deviation.

That is, a pressure of 5 to 6 bf/- is supplied to the supply pressure port 36, and this is exclusively used as an input to the air supply side valve 28. The output of the air supply side valve 28 is guided to the exhaust side valve 31, and at the same time, the output is sent to the pilot chambers 23a, 2 via the switching valve 52 as operating pressure.
Which brings us to 3b.

This operating pressure is input to the control circuit by the second pressure sensor 58, the air supply side valve 28 and the exhaust side valve 31 are turned on and off, and the pressure in the pilot chambers 23a, 23b is controlled. Further, the deviation between the first pressure sensor 32 and the input signal is determined, and the switching valve 52 is operated. If the input signal is larger than the signal from the first pressure sensor 32, the pilot chamber lower part 23b can be pressurized, and if it is smaller, the pilot chamber upper part 23b can be pressurized.
Switch so that a can be pressurized. This allows the operating pressure to be controlled using the minimum amount of air required.

When the input signal changes to lower the set pressure, the switching valve 52 is switched to pressurize the pilot chamber upper part 23a based on the deviation between the input signal and the signal from the first pressure sensor 32 of the set pressure port 15. At this time, the lower part 23b of the pilot chamber becomes atmospheric pressure.

A first pressure sensor 32 connected to the previous deviation signal and operating pressure
The deviation is taken again with the signal, and the intake valve 28 and the exhaust valve 31 are turned on and off so that this deviation becomes smaller. In other words, the operating pressure corresponding to the previous deviation signal is sent to the diaphragm chamber upper part 23a.

At this time, the diaphragm 21 is pushed down and the lower opening/closing part 16 opens and the air in the set pressure port 15 flows to the vacuum pressure port 14.

When the pressure at the set pressure port 15 decreases, the deviation between the input signal and the first pressure sensor 32 decreases, and the operating pressure approaches atmospheric pressure, so the opening degree of the opening/closing portion 16 decreases. , when the deviation is zero, the equilibrium state shown in Figure 10.11 is reached.

Then, when the input signal changes to increase the set pressure,
Similarly to the above, the switching valve 52 operates to pressurize the pilot chamber lower part 23b based on the deviation between the first pressure sensor 32 and the input signal (at this time, the pilot chamber upper part 23a becomes atmospheric pressure).

A second pressure sensor 58 connected to this deviation signal and the operating pressure
The deviation is taken again with the signal, and the intake side valve 28 and the exhaust side valve 31 are turned on and off in a manner that follows the previous deviation signal, and the operating pressure is sent to the pilot chamber lower part 23b. Therefore, the diaphragm 21 is pushed up and the upper opening/closing part 37
opens and air in the supply pressure port 36 flows to the set pressure port 15.

Then, as the pressure at the set pressure port 15, that is, the signal from the first pressure sensor 32 approaches the input signal (as the deviation signal becomes smaller), the operating pressure approaches atmospheric pressure. Therefore, the opening degree of the opening/closing part 37 becomes smaller, and when the deviation is O, an equilibrium state is reached.

In the above operation, the supply pressure port 36 is
Since a pressure of 6 kgf/di is supplied, vacuum breaking can be performed with a faster reaction.

Further, if a deviation occurs, a faster response can be expected if the pilot chambers 23a and 23b, which are at atmospheric pressure, are guided to the vacuum side.

Note that the present invention is not limited to the configuration of each of the embodiments described above. For example, in the third embodiment described above, a pressure port other than the supply pressure port 36 is provided, and the pressure chamber 23a is supplied from this pressure port. , 23b so that the operating pressure is supplied to further improve responsiveness, etc. It is also possible to arbitrarily change the configuration of each part without departing from the spirit of the invention. .

[Effect of the invention] Since this invention is configured as explained above,
It is possible to minimize gas leakage, and to make effective use of gas, especially in pressure control of high-pressure supply gas, when the pressure supply source is a cylinder or the amount of gas is limited. It has the excellent effect of being able to

[Brief explanation of the drawing]

Fig. 1 is a front sectional view showing a first embodiment of a pressure control valve embodying the present invention, Fig. 2 is a piping diagram showing an overview of the dispenser device, and Fig. 3 is a block diagram showing the circuit configuration of the liquid supply device. 4 and 5 are explanatory diagrams explaining the operation of generating drive signals for the exhaust side and intake side valves in the control valve, and FIG. 6 is a second practical example of the pressure control valve of the present invention. 7 is a side sectional view of the pressure control valve, FIG. 8 is a schematic diagram of the control device including the pressure control valve, FIG. 9 is a block diagram showing the circuit configuration of the control device, and FIG. 11 is a side sectional view of the pressure control valve, FIG. 12 is a schematic diagram of a control device including the pressure control valve, and FIG. 13 is a front sectional view showing a third embodiment of the pressure control valve of the present invention. FIG. 2 is a block diagram showing a circuit configuration of a control device. 5...Pressure control valve, 13...Gas flow path-16...
・Opening/closing part, 21...Diaphragm, 23a, 23b・
...Pressure chamber, 28...Air supply side valve constituting the control means,
31... Exhaust side valve constituting the control means.

Claims (1)

[Claims] 1. An opening/closing part (16) that opens and closes the high-pressure or low-pressure gas flow path (13);
), a diaphragm (21) that opens and closes the pressure chamber (
a pressure sensor (32) for detecting the pressure in the pressure chamber (23a); and a pressure sensor (32) for detecting the pressure in the pressure chamber (23a).
3a) control means (28,
31) A pressure control valve characterized by comprising: