JPH0384283A - Flow rate regulating valve with closing function - Google Patents

Abstract

PURPOSE:To control a secondary pressure with high precision without being influenced by heat generation of the coil of a drive part by a method wherein a pressure sensor to detect a fluid pressure is located on the secondary pressure side, and a valve opening and thus a secondary pressure is controlled by a valve drive part so that a pressure valve is adjusted to a target value. CONSTITUTION:With a valve drive part 50 charged with a current, a first plunger 2 is magnetized and lifted up. Through the action of the magnetic force of a valve drive part, a second plunger 6 is attracted to the first plunger 2. Therefore, a proportional valve 7 and a valve 9 are opened, the valve drive part 50 is controlled so that a secondary pressure P2 detected by a pressure sensor 19 is adjusted to a value equal to a secondary pressure being a target. When a feed current is stopped, the first and second plungers 2 and 6 are lowered in a sliding state within sleeves 1 and 4 and valves 7 and 9 secured to the plungers 2 and 6 are seated to valve seats 8 and 10, respectively, to shut off a flow passage. Since a cushion 5 of a non-magnetic substance, e.g., rubber, is mounted to the upper part of the second plunger 6, even when a foreign matter is located to the first plunger 2, the valve 9 is operated to prevent leakage of fluid.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a flow rate regulating valve with a closing function used in water heaters, instantaneous water heaters for baths, etc., and gas appliances such as gas fan heaters.

[Prior Art] Conventional flow rate regulating valves typically include a proportional valve having a fluid pressure regulating function and two independent solenoid valves having a closing function, arranged in series. The proportional valve referred to here is one that controls the fluid pressure at the outlet of the flow rate regulating valve.

In a proportional valve, since the valve and the valve seat are made of a rigid body, the airtightness during closing is insufficient and a sufficient closing function cannot be obtained. Therefore, in conventional flow rate regulating valves, in addition to the above-mentioned proportional valve, an elastic member (valve) and a rigid member (
Use a solenoid valve combined with a valve seat). Moreover, if foreign matter gets into the sliding part between the plunger and the sleeve of the electromagnetic valve, the valve's closing function will deteriorate. In order to prevent a decrease in the closing function, it is necessary to provide two solenoid valves so that even if one of the valves decreases in function, the other one compensates for the decrease in function.

FIG. 3 shows a conventional example. In Figure 3, fluid population 31
A fluid flow path is formed between the flow path and the fluid outlet 32, and in this fluid flow path, as shown in FIG.
1 and a solenoid valve B2 are provided.

Normally, the same solenoid valves B, , B are used.

In the proportional valve A, a sleeve 34 is attached to the opening of the plate 33.
An adjustment guide 35 fitted therein is attached, and an adjustment spring 37 that biases the plunger 36 slidable within the sleeve 34 toward the closed position is attached to the spring guide 39 via an adjustment screw 38 screwed into the adjustment guide 35. is in contact with. provided coaxially with the plunger 36 and the plunger 3
A pan 41 is brought into contact with the bushing guide 40 which is brought into contact with the bottom of the valve 6, and the bread 41 is supported within the flow path of the main body 43 of the flow rate regulating valve via a diaphragm 42. In addition, a diaphragm 42 is installed in the case 44 that covers the flow rate regulating valve body 43.
A boat 45 is provided that communicates the back or upper space of the vehicle with the outside air.

A proportional valve 47 made of a rigid material and having a valve shaft 46 is arranged coaxially with the pan 41 below the pan 41, and the effective area of the proportional valve 47 is approximately equal to the effective area of the diaphragm 42. It is formed. Reference numeral 50, which presses the proportional valve 47 from below against the proportional valve seat 49 made of a rigid material by means of the proportional valve spring 48, is a proportional valve driving section made of an electromagnetic coil or the like.

In the solenoid valves B and B2, 51 is a plate, 52 is an inner yoke, 53 is a cushion, 54 is a sleeve, and 55
56 is a valve made of an elastic material; 57 is a valve seat; 58 is a valve spring that urges the valve seat; 59 is a cover plate; and 60 is a solenoid valve drive unit. show. In addition, P,,P, is the flow rate adjustment valve body 4
The primary pressure and secondary pressure of the fluid in 3 are shown, respectively.

When the fluid is city gas, the primary pressure P1 of the gas is, for example, -
Although the secondary pressure P2 varies depending on the time of day, the secondary pressure P2 of the gas must be approximately constant considering the gas appliances and the like to be used. That is, the purpose of the proportional valve is to always keep the secondary pressure constant regardless of changes in the primary pressure.

Fluid pressure (primary pressure) from the fluid supply source as shown in Figure 3
When Pl is applied, the upward force and downward force applied to the proportional valve 47 cancel each other out because the effective areas of the diaphragm 42 and the proportional valve 47 are formed to be the same. Therefore, the proportional valve 47
By operating (pressing down) the fluid pressure at the outlet through the proportional valve part toward the outlet 32 is throttled to 2 abdominal pressure Pt, and if the above effective area is A, the proportional valve 47 has (Pg The pressing force of the XA10 proportional spring 48 acts upward on the proportional valve 47. The proportional valve drive unit, that is, the electromagnetic coil 50 is energized to pull down the plunger 36, thereby pushing down the proportional valve 47 and leaking intra-abdominal pressure P. From the above-mentioned balance relationship, P2 pressure is the current supplied to the electromagnetic coil 50. It is kept constant at a set value which is proportional to the pulling force of the plunger 36 which is proportional to the value.

[Problems to be Solved by the Invention] As mentioned above, in consideration of fluid leakage, the conventional flow rate regulating valve has two electromagnetic valves arranged in series in addition to the proportional valve, and the load adjustment of the proportional valve is This was performed using a driving method such as a plunger type, a moving coil type, or a repulsion between a permanent magnet and an electromagnet, and the two abdominal pressure P2 was controlled by the driving current value, which had the following drawbacks.

B. Since the secondary pressure is controlled by the current value supplied to the drive section, the current value may change due to heat generation in the coil of the drive section, etc.

Therefore, the control accuracy of the secondary pressure is not good.

Due to hysteresis caused by contact resistance of the sliding portion of the opening and the drive unit, the precision of the secondary pressure to be controlled is poor.

C. It is necessary to provide a special abnormality detector to detect abnormalities such as leakage of the electromagnetic valve and failure of the proportional valve.

Second, since it is composed of a plurality of electromagnetic valves and one proportional valve, the fluid flow path is complicated, and therefore the passage resistance is large. Furthermore, since there are many parts, the cost is high and a large space is required.

[Means to solve the problem]

The above problem is solved by a first plunger that is slidably disposed within a first sleeve that is secured within a valve drive, and that is adjustable and pushed through the first plunger via a first valve spring. A lowering adjusting screw and a second sleeve fixed to the lower part of the first plunger, and a balance diaphragm fixed to the artificial side flow path of the flow rate regulating valve and a valve at the lower part of the second sleeve. a ring-shaped proportional valve made of an elastic material fixed through a guide;
The effective areas of the balance diaphragm and the proportional valve are approximately equal, and a disc-shaped valve made of an elastic material is disposed inside the annular proportional valve via a flexible portion. The disc-shaped valve is the second valve mentioned above.
A proportional valve seat and a proportional valve seat corresponding to the annular proportional valve and disc-shaped valve are provided in the lower part of the second plunge slidably provided in the sleeve of the flow rate regulating valve. A pressure sensor is provided which is connected to the valve seat and the valve driving section via a control circuit, and the space between the annular proportional valve and the disc-shaped valve is connected to the back space of the balance diaphragm via a communication passage. This is solved by a flow HJ regulating valve with a closing function that is connected to the valve.

〔Example〕

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Components having the same functions as those in FIG. 3 are designated with the same reference numerals.

In FIG. 1, a first sleeve l having a vertically adjustable spring guide 39 and a cylindrical first plunger 2 is fixed to the upper part of the inside of the valve drive unit, that is, the electromagnetic coil 50. The upper part of the first sleeve is a plate 33
This adjustment guide 3 is covered by an adjustment guide 35 attached to the
An adjustment screw 38 at the upper part of the spring guide 39 is screwed into the screw hole provided at 5. A first valve spring 3 is provided between the spring guide 39 and the first plunger 2 in the first sleeve l. A second sleeve 4 that can slide inside the first sleeve 1 is fixed to the lower part of the first plunger 2, and a non-magnetic material made of an elastic material such as rubber is attached to the upper part of the second sleeve 4. A cylindrical second plunger 6 having a cushion 5 is slidably disposed.

An annular proportional valve 7 made of an elastic material is formed at the lower part of the second plunger 6 so as to face a proportional valve seat 8, and an annular proportional valve 7 is formed concentrically and integrally with the proportional valve 7 inside the proportional valve 7. A closing valve 9 made of a disc-shaped elastic material is formed to face a valve seat 10 communicating with the outlet 32. To explain in more detail, the lower part of the second sleeve 4 includes a stopper 11 fitted onto the second sleeve 4, a balance diaphragm 12 fixed to the flow valve main body 43, and a valve guide 13 fixed to the proportional valve 7. The members 11, 12, and 13 are integrated by bushing nuts 14 which are superimposed one above the other and are spring-fitted into the second sleeve 4. Further, the above-mentioned valve 9 is integrally formed with the proportional valve 7 together with the flexible portion 15, and a second valve spring 16 is provided between the valve guide 13 and the valve 9 to push the valve 9 downward toward the valve seat 10.
is provided. The effective area of the balance diaphragm 12 is formed to be equal to the effective area of the proportional valve seat 8.

The back space 17 of the balance diaphragm communicates with the space between the proportional valve 7 and the valve 9 via a communication passage 18 provided in the flow control valve body 43. A pressure sensor 19 is provided at an appropriate position of the outlet 32, and is connected to a valve drive unit 50 via a control circuit 20'.

In the initial state, the adjusted first valve spring 3 and the second valve spring 3 are adjusted.
The proportional valve 7 and the valve 9 are pressed against their respective valve seats 8 and 10 in an airtight manner by a valve spring 16.

One abdominal pressure P1 of the fluid acts in the direction of closing the proportional valve 7, but since the effective areas of the balance diaphragm 12 and the proportional valve 7 are set to be the same, the upward force acting on the proportional valve 7 is reduced to the downward force. balance with power. When a current is applied to the valve drive section 50 as shown in the characteristic diagram shown in FIG. Since it is attracted by the plunger 2, the proportional valve 7 and the valve 9 are opened, and the valve drive unit 50 is controlled so that the 2-abdominal pressure P2 detected by the pressure sensor 19 is equal to the target secondary pressure. Moreover, when the supply current is stopped, the first plunger 2 and the second plunger 6 slide down inside the respective sleeves 1 and 4, and the respective plungers 2
．． Valves 7 and 9 fixed to valve 6 are seated on respective valve seats 8 and 10 to block the flow path. Since the cushion 5 made of non-magnetic material such as rubber is provided on the upper part of the second plunger 6, even if the first plunger 2 is stuck to the first sleeve 1 due to the presence of foreign matter or the residual magnetism of the electromagnetic coil 50, the second plunger The plunger 6 and therefore the valve 9 operate unaffected by them to prevent fluid leakage.

〔Effect of the invention〕

A pressure sensor that detects the fluid pressure is installed in the secondary pressure, and the valve opening and therefore the secondary pressure are controlled with high precision by the valve drive unit so that the target pressure value is achieved, so that changes in current value due to coil heat generation in the valve drive unit are prevented. It is not affected by hysteresis, etc., and can detect abnormal conditions such as valve leakage using a pressure sensor. Also, the structure allows one valve drive unit to open and close two valves and adjust the flow rate of the proportional valve. It has many advantages, such as a reduced number of parts and therefore lower manufacturing costs, as well as a simpler and more compact flow path.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a characteristic diagram of a valve driving section of the present invention, and FIG. 3 is a sectional view showing a conventional technique. ■...First sleeve, 2...First plunger, 3...First valve spring, 4...Second sleeve, 6...Second plunger, 7... Proportional valve, 8... Proportional valve seat, 9
...Valve, 10...Valve seat, 12...
Balance diaphragm, 13... Valve guide 15... Flexible part, 16... Second valve spring, 17... Back space, 18... Communication path, 19... Pressure sensor, 20... ...control circuit, 38.
...No adjustment, 50... Valve drive section. Cross-sectional view of an embodiment of the present invention

Claims (1)

[Claims] 1. A first sleeve (
1) a first plunger (2) slidably disposed within the first plunger (2);
an adjustment screw (38) that adjustably pushes down the first plunger via the first valve spring (3); and a second sleeve (4) fixed to the lower part of the first plunger. A balance diaphragm (12) is fixed to the inlet side flow path of the flow rate regulating valve, and a ring-shaped proportional valve (7) made of an elastic material is fixed to the lower part of the second sleeve via a valve guide (13). ), and the effective areas of the balance diaphragm and the proportional valve are approximately equal, and the annular proportional valve has a flexible portion (15) and a disc integrally formed inside. A disk-shaped valve (9) is provided at the bottom of the second plunger (6) slidably provided in the second sleeve, and the disk-shaped valve is provided on the outlet side of the flow rate regulating valve. The flow path includes a proportional valve seat (8) and a valve seat (10) corresponding to the annular proportional valve and disc-shaped valve, and a control circuit (20).
A pressure sensor (19) is provided which is connected to the valve driving section through a pressure sensor (19), and the space between the annular proportional valve and the disc-shaped valve is connected to the back space (17) of the balance diaphragm and a communication passage (18). A flow rate adjustment valve with a closing function that is communicated through.