JPS6034580A - Valve device - Google Patents

Abstract

PURPOSE:To prevent a malfunction due to clogging by providing a throttle in a main valve and attaching a filter and the main valve together surrounding such throttle. CONSTITUTION:The surrounding of the valve shaft of a main valve 24 is covered by a filter 28 which is attached to cover a first throttle 25. When an actuation valve 34 is open, the water which has been filtered its foreign substance by the filter 28 flows from a pressed water passage 3 into a main valve back pressure chamber 27 via the first throttle 25, and flows out into a pressure-amplifying chamber 16 via a second throttle 33 and a pressure-amplifying chamber 37. At this time, a pressure capable of opening the main valve 24 is applied to a diaphragm 30. When the water delivery is increased to cause the actuation valve 34 to close the second throttle 33, the pressure to the diaphragm 30 is lost to cause the main valve 24 to be drawn toward the valve seat 23 to close.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a valve device, and particularly to a valve device having a relatively narrow fluid passage configured to prevent malfunction due to blockage.

In general, pilot-operated on-off valves that operate valves that receive relatively large pressures due to force changes such as relatively small pressure fluctuations usually have relatively narrow fluid passages and sliding parts. For this reason, foreign matter such as dust gets into the passageway, which tends to cause malfunctions and locks due to clogging, and a filter is used to prevent this. However, when the filter is incorporated into the valve device, a relatively large space is required for the filter, and the structure is complicated. Further, there is a drawback that the filter becomes inoperable due to clogging, and cleaning the filter takes time and effort.

SUMMARY OF THE INVENTION An object of the present invention is to provide a valve device configured to prevent foreign matter from entering a fluid passage and to prevent malfunctions due to clogging.

According to the present invention, the above object is achieved by a main valve that opens and closes a fluid flow passage, a throttle that communicates the flow passage with a pressure chamber whose pressure is lower than that of the flow passage, and a pressure difference between before and after the throttle. This is achieved by providing a throttle in the main valve and integrally attaching a filter to the main valve surrounding the throttle in a valve device equipped with a pressure-receiving pushing body that applies force to open and close the main valve.

Hereinafter, the present invention will be described in detail together with embodiments shown in the drawings.

FIG. 1 and the following illustrate one embodiment of the present invention. In this embodiment, a pump that is commonly used in a combination of a rotary pump and a jet pump, which is widely used for shallow wells, is illustrated. It is.

In Fig. 1, the reference numeral 1 indicates a turbine pump.
A discharge pipe 2 is provided at one end thereof, and is further connected to a jet pump 5 via a pressure waterway 3 and a discharge waterway 4. A suction pipe 7 is connected to one end of the jet pump 5 via a check valve 6, and the lower end of the suction pipe 7 is inserted into a water source 8. The jet pump 5 is constructed as shown in FIGS. 2 and 3.

That is, the jet pump 5 has a jet pump body 9
A suction passage 10 is formed on the check valve 6 side of the body 9, and a bent conduit 11 communicating with the pressure waterway 3 faces into this suction passage 10, and a nozzle is provided at the tip of the suction passage 10. 12 are provided. A first venturi 13 is fixed in the body 9 facing this nozzle 12, and this first venturi 13 is connected to the bypass water passage 14f:
, and a tubular check valve 15 is provided downstream thereof.

A second venturi 17 is arranged on the same axis with the first venturi 13 and the pressure increase chamber 16 in between. The second venturi 17 also includes a water passageway 18 and a tubular check valve 19.

Note that this second venturi 17 is provided integrally with a valve device 20, which will be described later, and which is inserted into the jet pump body 9.

The valve device 20 is watertightly attached to the jet pump body 9 through a packing 21 with bolts or the like, and has a water channel coaxial with the pressure water channel 3 and the discharge water channel 4; Above said second venturi 17
is located.

By the way, the valve device 20 has a partition wall 22 on the pressure waterway 3 side, a valve seat 23 is formed in the partition wall 22, and a main valve 24 faces the valve seat 23. The main valve 24 has a first throttle 25 formed in a part of its valve shaft,
This first restrictor 25 communicates with a main valve back pressure chamber 27 within a case 26 fixed to the upper end of the valve device 20 . The area around the valve shaft of the main valve 24 is the first throttle! It is covered by a filter 28 attached so as to cover 1l125. The upper end of the main valve 24 is supported by a diaphragm 30 whose periphery is held between the case 26 and the base 29, and the base 29 is connected to the valve device by a bolt 32 via a packing 31, as is clear from FIG. It is fixed to the body of 20.

A second throttle 33 is provided in the middle of the case 26, and the tip of the operating valve 34 faces the second throttle 33. The operation valve 34 is supported by a diaphragm 36 whose peripheral edge is held between the upper end of the case 26 and the cover 35, and the diaphragm 36 converts the space on the case 26 side into a pressure intensifying chamber 37, and The space on the side of the cover 35 is a venturi front pressure chamber 38. As is clear from FIG. 3, the pressure increase chamber 37 is communicated with the pressure increase chamber 16 of the jet pump 9 through a relief passage 39, so that the pressures therebetween are made equal. Further, the venturi prepressure chamber 38 is communicated with the suction passage IO through the communication pipe 40 and the check valve 6, so that the pressures therebetween are made equal.

As is clear from FIG. 3, the valve device 20 is fixed to the jet pump body 9 via the valve body 41 with bolts or the like via the packing 20.

Next, the operation of this embodiment configured as above will be explained.

If the pressure in the pressure increase chamber 16 when the main valve 24 facing the pressure waterway 3 is closed is tl - that when the PIC1 is open is Pa, then the relationship between the pumped water amount and the pressure is as shown in Figure 4. Become. The operation valve 34 adjusts the pressure pH on the suction passage 10 side in FIG.
Ps-Pea, which is the difference between

The receiving pressure F+ of the diaphragm 36 which is pushed by the pressure difference of pH-PIl and the receiving pressure F2 due to the pressure PM in the main valve back pressure chamber 27 which the operating valve 34 receives according to the opening area of the second throttle υ33. It operates based on the resultant force.

Now, when the main valve 24 is open, a jet flow is generated from the nozzle 12, so a force F expressed by the following equation is applied to the operating valve 34 in the direction of closing the second throttle 33.

F=Ft f+ fz = AI (Pst - Pg□) ft La...
(1) In equation (1), fl is the second throttle applied to the operation valve 34, 933f is the elastic force of the diamond slam 36 applied in the opening direction, and f2 is the amount due to the jet flow from the 20th teaching valve 33. The resulting drag, A1, is the effective pressure receiving surface of the diaphragm 36, and fdPghPH is the pressure before and after the nozzle 12 of the suction passage 25. In Fig. 4, the amount of pumped water Q is QA
When it is smaller than F, it is set so that it becomes 0.

When the operation valve 34 is open, the water from which foreign substances have been removed by the filter 28 flows from the pressure waterway 3 into the main valve back pressure chamber 27 via the first throttle sheath 25, and the water flows into the main valve back pressure chamber 27 through the second throttle sheath 33 and the It flows out to the pressure intensification chamber 16 through the pressure chamber 37 and the relief waterway 39. At this time, a pressure difference corresponding to the pressure drop caused by the first restrictor 25 is applied to the diaphragm 30, creating a receiving pressure capable of opening the main valve 24.

Then, as the pumped water amount Q increases and QA also becomes thicker, the value of F in equation (1) becomes positive, and the operation valve 34 becomes
Close the diaphragm 33. Then, since the amount of water flowing through the first restrictor 25 becomes zero or almost zero, the pressure received by the diaphragm 30 disappears, and the main valve 24 is drawn toward the valve seat 23 and closed. As a result, the combined pump performs the water pumping action instead of the work of the turbine pump 1 alone. At this time, the operating valve 34 closes in response to the force F expressed by the following equation, and Qa and J:p in FIG. 4 are also set so that F>0 with a large pumped water amount.

F”'Ft Fx ft = At (Pat Pac) F2 ft --(
2) Set the water pumping amount to Qs! :f) also becomes smaller,
F(O), and the operating valve 34 opens.

In this way, the main valve 24 opens and closes, but when the main valve is open, the jet pump performs a pressure increasing action, and when combined with the turbine pump, water is supplied at a relatively high discharge pressure. When the main valve 24 is closed, water is supplied at a relatively low discharge pressure by pressurizing only the turbine pump.

By the way, the conventional method having a jet pump with 11 venturis is a single venturi method, a method having two venturis in series, a two-stage venturi method, and a method in which the pressure waterway 3 is opened and closed using the main valve 24. Fig. 5 shows the characteristics of the efficiency η and the discharge pressure Hd with respect to the amount of pumped water Q in each method, and the noise dB
(A scale) and the relationship between power consumption and pumped water amount Q is shown in FIG.

In other words, in Fig. 5 2 and Fig. 6, the chain line (a) indicates the single venturi type, the line (b) indicates the two-stage venturi type, and the line (c) indicates the nozzle opening/closing type. are shown respectively.

In all methods! The m-pulsation pump is designed to have approximately equal Q-H characteristics, that is, equivalent pumping characteristics, within a relatively small range of water volumes. @Figures 5 and 6 show the experimental results when the suction height was 6 m.

In the conventional single venturi type, cavitation occurs in the venturi, and there is a point at which the pressure increase in the jet pump becomes impossible (pumped water amount Q = Qc in Figure 5), and if the water immersion exceeds this point, Not only is the efficiency significantly reduced, but also the noise is significantly increased due to cavitation that occurs near the pumped water mQc.

On the other hand, with the two-stage venturi type, the jet pump works effectively over the entire pumping area, improving efficiency and eliminating sudden increases in noise. Since the amount of pressure increase per venturi can be reduced, noise is reduced overall.

In addition, in the nozzle opening/closing type, the main valve is closed and the turbine pump performs the pumping action independently, so although the discharge pressure is slightly lower than that of the single-stage ventilly type, the efficiency is significantly increased because the consumed mineral power is reduced, and Jet pump nozzle 12
Since there is no water jetting into the tank, there is no collision between the water and the noise is significantly reduced.

It is clear that by combining the two-stage venturi type and the nozzle opening/closing type as described above, both efficiency and noise can be significantly improved.

In addition, at the point where the pumping amount Q is maximum, cavitation occurs on the suction side of the turbine pump, causing a sudden drop in the discharge pressure and a sudden increase in noise, but this occurs near the maximum pumping amount. This problem can be solved by using known means to limit the amount of pumped water, and no problem will occur.

As described above, the filter 28 of the valve device 20 applied to the combination pump is provided integrally with the main valve 24, so when the main valve 24 opens and closes, it moves as one and does not adhere to the filter 28. The foreign matter that is attached to the main valve 24 is easily peeled off by the 1M impact when the main valve 24 opens and closes, and does not cause clogging.

Furthermore, when the main valve 24 is open, a water flow is generated outside the filter 28 to prevent foreign matter from adhering to it.

The filter 28 and the first restrictor 25 are connected to the main valve 24.
Since it is provided integrally with the filter 28, it does not require a large installation space, and it can be
Since the main valve 24 can be attached and detached at the same time as the main valve 24 without requiring any additional parts to fix it, the structure of the entire valve device can be simplified and the ease of assembly is improved.

As is clear from the above description, according to the present invention, since the throttle and filter are provided integrally with the main valve, it is possible to obtain a valve device that does not cause clogging.

[Brief explanation of the drawing]

The figures are for explaining one embodiment of the present invention, in which figure g1 is a side view of a combination pump, figure 2 is a vertical side view of a jet pump, figure 3 is a partially cutaway front view of figure 2, Figure 4 is a diagram showing the relationship between the amount of water pumped and the pressure of the jet pump, Figure 5 is a diagram showing the relationship between the amount of water pumped, efficiency and total head, and Figure 6 is a diagram showing the relationship between the amount of water pumped and the jet pump pressure.
The figure is a diagram showing the relationship between pumped water amount, noise level, and power consumption.

Claims (1)

[Claims] 1. A main valve that opens and closes the fluid passage, and a main valve provided in the main valve,
A diaphragm that communicates the fluid passage with a low-pressure pressure chamber, a pressure-receiving pushing body that applies force to open and close the main valve based on the pressure difference before and after the diaphragm, and a pressure-receiving pushing body that surrounds the diaphragm and connects the main valve to the main valve. A valve device characterized by having an integrally mounted filter.