CN202811398U - Integrated control valve for constant jetting height and check valve - Google Patents

Integrated control valve for constant jetting height and check valve Download PDF

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Publication number
CN202811398U
CN202811398U CN 201220511850 CN201220511850U CN202811398U CN 202811398 U CN202811398 U CN 202811398U CN 201220511850 CN201220511850 CN 201220511850 CN 201220511850 U CN201220511850 U CN 201220511850U CN 202811398 U CN202811398 U CN 202811398U
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China
Prior art keywords
valve
pressure
connection mouth
way valve
port
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Withdrawn - After Issue
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CN 201220511850
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Chinese (zh)
Inventor
郑全
郑建伟
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SANYE SCIENCE AND TECHNOLOGY Co Ltd GUANGZHOU
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SANYE SCIENCE AND TECHNOLOGY Co Ltd GUANGZHOU
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Abstract

The utility model discloses an integrated control valve for a constant jetting height and a check valve. The integrated control valve for the constant jetting height and the check valve is in an integrated structure and comprises four connectors externally connected with pipes. The integrated control valve comprises a first needle valve (2), a first one-way valve (3), a guide valve (4), a second one-way valve (5) and a second needle valve (6). The guide valve (4) comprises a three-way valve, a first pressure testing cabinet and a second pressure testing cabinet. The three-way valve is controlled by the coordination of pressure tested by the first pressure testing cabinet and pressure tested by the second pressure testing cabinet. According to the integrated control valve for the constant jetting height and the check valve, a pressure testing cabinet is added to test pressure of a water inlet of a water pump, and a guide valve film is moved by water pressure from two directions to generate differential motion instead of being moved by water from one direction to generate the differential motion. The influence, caused by the change of a net suction head of the water pump, on outlet flow of the water pump is overcome, and therefore the pressure of the water outlet is exactly equal to a jetting height. The integrated control valve for the constant jetting height and the check valve is compact in structure and simple and the using reliability is largely enhanced.

Description

The integrated control valve of permanent hoisting height/check valve
Technical field
The present invention relates to the hydraulic control valve gate technique, more specifically the integrated control valve of the special-purpose permanent hoisting height/check valve of a kind of water pump.
Background technique
Water supply system is safely the modern focus that ensures water supply system and fire supply system; and the fluctuating widely of ductwork pressure (device lift); make water pump substantial deviation declared working condition point, will directly cause like this water pump to be shut down because of overload, thereby cause systemic breakdown.
The patent No. is that the utility model patent of ZL200620056901.3 discloses permanent hoisting height/check water pump dedicated valve, and the patent of invention of ZL201020104297.3 discloses a kind of multi-functional control valve of water pump.These two kinds of valves all can adapt to fluctuating widely of ductwork pressure, automatic regulating valve door aperture, and stabilize water delivery side of pump pressure makes water pump can not depart from the declared working condition point, thus water pump can not shut down because of overload and made systemic breakdown.
But these two kinds of valves all have the use narrow limitation, and this is because the outlet pressure of water pump only when equalling zero, just is equal to the lift of water pump at unit fixed on water pump suction pressure (clean suction head).Larger as working as inlet pressure, the outlet pressure of water pump and lift differ larger! That is to say that valve can not permanent lift, and is permanent exit of pump pressure! The outlet pressure of water pump is larger with lift phase difference, will make that to cause water pump to depart from declared working condition point far away, and overload is just more serious! System is just more dangerous!
Unit fixed on water pump suction pressure is universal phenomenon greater than zero operating mode, when many large-scale fire-fighting systems adopt the standing vessel retaining, tend to cause water tank when high water level, seriously to transship, the declared working condition that only can just get back to water pump when the water of water tank is finished is brought great puzzlement with regard to the feed water pump design selection like this.Because water pump departs from the declared working condition point, the pump working flow could make the calculating water storage capacity not reach the flame extinction time of design greater than the design rated flow more seriously! Have a strong impact on the usefulness of fire extinguishing operation.
The stable problem of unit fixed on water pump suction pressure variable effect pump operating point is the unsolved difficult problem of industry always, and the invention of the integrated control valve of this permanent hoisting height/check valve solves an above difficult problem up hill and dale.
Summary of the invention
The object of the invention is to for the deficiencies in the prior art, a kind of integrated control valve of permanent hoisting height/check valve is provided.
Technological scheme of the present invention is as follows:
The integrated control valve of permanent hoisting height/check valve, it is an overall structure, the connection mouth that comprises four external pipes, be respectively the first connection mouth, the second connection mouth, the 3rd connection mouth and the 4th connection mouth, described integrated control valve comprises the first needle-valve, the first one-way valve, pilot valve, the second one-way valve and the second needle-valve, described pilot valve comprises three-way valve, the first pressure measuring chamber and the second pressure measuring chamber, three-way valve is subjected to the first pressure measuring chamber and the second pressure measuring chamber institute measuring pressure Collaborative Control, the first pressure measuring chamber is communicated with the second connection mouth, the second pressure measuring chamber is communicated with the first connection mouth, the first connection mouth also is communicated with an end of the second needle-valve, the other end of the second needle-valve is communicated with the entrance of the second one-way valve, the outlet of the second one-way valve is communicated with the first port of three-way valve, one end of the first needle-valve is communicated with the 3rd connection mouth, the other end of the first needle-valve is communicated with the entrance of the first one-way valve, the outlet of the first one-way valve is communicated with the 4th connection mouth, the 4th connection mouth is communicated with the second port of three-way valve, and the 3rd connection mouth is communicated with the 3rd port of three-way valve.
Further, the first port of three-way valve is communicated with the second port, when the difference of the hydrodynamic pressure of the hydrodynamic pressure of the second pressure measuring chamber and the first pressure measuring chamber does not reach the threshold value of setting, the 3rd port closed, when the difference of the hydrodynamic pressure of the hydrodynamic pressure of the second pressure measuring chamber and the first pressure measuring chamber reached the threshold value of setting, the first port of three-way valve, the second port were communicated with the 3rd port.
Further, pilot valve comprises main valve stem protecting cover, main valve stem, spring capping, main spring, spring pad, diaphragm, upper valve core, sealing gasket, middle spool, lower valve core, the lower valve core spring that links to each other successively, the first pressure measuring chamber is arranged at the top of diaphragm, the second pressure measuring chamber is arranged at the below of diaphragm, controls the first port of three-way valve and break-make and the aperture between the 3rd port by sealing gasket.
The present invention overturns traditional control structure and the connecting means of hydraulic control valve, and traditional connecting means as shown in Figure 2.The present invention is called a kind of Chinese invention patent (patent No.: 201010103041.5) on the basis of disclosed pilot valve of control valve of water pump in name, it only has a pressure measuring chamber to measure the water pump water outlet mouth pressure, the present invention increases the water intake pressure that another pressure measuring chamber is measured water pump, it is mobile to make the pilot valve diaphragm produced by hydraulic pressure by original one direction, becomes that two-way produced by hydraulic pressure differential.Change and produce impact on the exit of pump flow thereby overcome the clean suction head of water pump, make outlet pressure really equal lift, permanent hoisting height/check valve is just really qualified.
The present invention is also with the integrated as a whole control valve of numerous auxiliary valves, pipe element and pilot valve.Integrated control valve compact structure, brief, operational safety improves greatly.Because integrated control valve can be connected with water pump, the corresponding position of hydraulic control valve with flexible nonmetallic tubing, thereby has saved a large amount of installing spaces, manpower and cost of material, and greatly improves the reliability that connects, and greatly reduces system failure rate.
Description of drawings
Fig. 1 is the application schematic representation of integrated control valve of the present invention;
Fig. 2 is the connection diagram of traditional control valve of water pump;
Fig. 3 is a kind of structural representation of integrated control valve of the present invention;
Fig. 4 is water pump H-Q plotted curve.
Embodiment
Below in conjunction with accompanying drawing the present invention is described in detail.
As shown in Figure 1, the integrated control valve 1 of permanent hoisting height/check valve of the present invention is an overall structure, comprising the first needle-valve 2, the first one-way valve 3, pilot valve 4, the second one-way valve 5, the second needle-valve 6.Integrated control valve 1 has the connection mouth of four external pipes, and the first connection mouth A, the second connection mouth B, the 3rd connection mouth C, the 4th connection mouth D are arranged respectively.The first connection mouth A is communicated with an end of the second needle-valve 6, and the other end of the second needle-valve 6 connects the entrance of the second one-way valve 5, and the outlet of the second one-way valve 5 connects the first port c of the three-way valve of pilot valve 4; The first connection mouth A also is communicated with the second pressure measuring chamber b of pilot valve 4.The second connection mouth B connects the first pressure measuring chamber a of pilot valve 4, usually is connected to the water outlet in pond (or water tank, water pot etc.) 14.The 3rd connection mouth C connects an end of the first needle-valve 2, and the other end of the first needle-valve 2 connects the entrance of the first one-way valve 3, and the outlet of the first one-way valve 3 connects the second port d of the three-way valve of pilot valve 4, and is communicated with the 4th connection mouth D; The 3rd connection mouth C also is communicated with the 3rd port e of the three-way valve of pilot valve 4.When using integrated control valve 1 of the present invention, the first connection mouth A is connected with the outlet (upstream cavity 10 of permanent hoisting height/check valve 8) of water pump 12, the second connection mouth B connects the entrance (this mouthful can unsettledly not connect when the water feeding of water pump mouth pressure was zero) of water pump 12, downstream cavity 9, the four connection mouth D that the 3rd connection mouth C connects permanent hoisting height/check valve 8 connect the control chamber 7 of permanent hoisting height/check valve 8.Usually, during application, be respectively equipped with the first pressure gauge 13 and the second pressure gauge 11 in entrance and the outlet of water pump 12.
Fig. 2 is and the connection diagram of control valve of water pump of the immediate prior art of invention, and the present invention compares with it, and pilot valve 4 has increased by the second pressure measuring chamber, thus real realization permanent lift.
Fig. 3 is a kind of embodiment of integrated control valve 1, and a among Fig. 3, b, c, d, e correspond to respectively a, b, c, d, e port among Fig. 1.As shown in Figure 3, integrated control valve 1 comprises: main valve stem protecting cover 401, O shape circle 402, main valve stem 403, spring capping 404, gland pin 405, spring shield 406, main spring 407, hexagon nut 408, spring washer 409, spring pad 410, hex head bolt 411, plain washer 412, diaphragm 413, upper valve core 414, upper valve body 415, O shape circle 416, O shape circle 417, O shape circle 418, sealing gasket 419, middle spool 420, needle-valve 2, lower valve core 421, sealing gasket 301, one-way valve 3, spring 302, O shape circle 422, middle valve body 423, O shape circle 424, lower valve core spring 425, lower valve body 426, O shape circle 427, inipple 428, honeycomb duct 429, needle-valve 6, sealing gasket 501, one-way valve 5, spring 502.
Control principle of the present invention:
From shown in Figure 4, during common pump selection, suppose that the water pump suction pressure is at 0 o'clock, the declared working condition point of water pump is A 1, its rated head is H 1, its rated flow is Q 1
But when the water pump suction pressure is P 1=h 2-h 1The time, because sucking energy, water pump increases, the H-Q curve of water pump is along the H P that axially gone up translation 1The operating point of water pump is A 2, its lift is P 2, its flow is Q 1
The patent No. is that the working principle that patent of invention that the utility model patent of ZL200620056901.3 discloses permanent hoisting height/check water pump dedicated valve and ZL201020104297.3 discloses a kind of multi-functional control valve of water pump is constant water delivery side of pump pressure, that is to say H 1Invariable.So actual operating point is A 3, its lift is H 1, its flow is Q 2Working flow has at this time exceeded Q 1Many, prime mover is seriously transshipped!
More than the permanent lift operating mode described of these two patents be could realize under given conditions, namely be P 2=H 1-P 1=H 1-(h 2-h 1), work as P 1=h 2-h 1Could set up P at=0 o'clock 2=H 1As long as P 1Be not equal to zero, translation all can occur in the H-Q curve, that is to say P 2≠ H 1But water pump is that its suction pressure is P often in the behaviour in service of reality 1All be not equal to zero, that is to say that permanent hoisting height/check water pump great majority are operated in constant pressure (exit of pump pressure H 1) operating mode, rather than be operated in permanent lift (H 1=P 2-P 1) operating mode.
As seen from Figure 4, really obtain permanent lift (H 1=P 2-P 1) operating mode, just must overcome P 1On the make progress impact of translation of curve, that is to say and to revise along H 1The operating point A of horizontal translation 3, again return operating point A 1Namely be that valve should be adjusted the minimizing aperture automatically, increase corresponding resistance, offset the pressure P that unit fixed on water pump suction increases 1, namely be with R 3Be adjusted into R 1, make operating point A 3Along H 1Horizontal adjustemt is to A 1Integrated control valve of the present invention detects respectively entrance and the outlet pressure of water pump 12 by two pressure measuring chambers are set at pilot valve 4, thereby makes operating mode can be stabilized in A 1, really realize permanent lift.
Basic functional principle of the present invention
⑴ (P 1=0) time:
1. hold the pressure operating mode
At first set to hold and press the operating point Parameter H 1, regulate main valve stem 403 spring capping 404 is moved up and down, adjust the pressure of main spring 407, make plain washer 412 promote diaphragm 413, interlock upper valve core 414 and sealing gasket 419 are closed the 3rd port e of the three-way valve of pilot valve 4.
After water pump 12 was opened, current divided two-way to enter from the first connection mouth A.The first via is by passing through interior hole path to the second needle-valve 6, the other end of the second needle-valve 6 connects the entrance of the second one-way valve 5 by interior hole path, the outlet of the second one-way valve 5 connects the first port c of the three-way valve of pilot valve 4 by interior hole path, then enter into the control chamber 7 of permanent hoisting height/check valve 8 by the 4th connection mouth D, permanent hoisting height/check valve 8 cuts out.The second the tunnel enters the second pressure measuring chamber b, the thrust that water generates is made progress to diaphragm 413 by interior hole path.As reaching Parameter H when water pump 12 outlet lifts 1The time, the thrust that diaphragm 413 makes progress overcomes the pressure of main spring 407, make upper valve core 414 interlock sealing gaskets 419 upwards, make the second port d and the 3rd port e conducting of three-way valve, water from the 3rd port e by the downstream cavity 9 of interior hole path from the 3rd connection mouth C to permanent hoisting height/check valve 8, thereby permanent hoisting height/check valve 8 is opened.
2. permanent lift operating mode
Because permanent hoisting height/check valve 8 has been opened, when the increase of system water amount, the pressure drop of permanent hoisting height/check valve 8 downstream cavity 9 descends the pressure of the upstream cavity 10 of permanent hoisting height/check valve 8 thereupon.At this moment the hydraulic pressure of the second pressure measuring chamber b descends, the thrust that diaphragm 413 makes progress descends, upper valve core 414 interlock sealing gaskets 419 are moved down, the first port c that flows through flows out to the discharge reduction of the 3rd port e again, make at last the discharge reduction by the downstream cavity 9 of interior hole path from the 3rd connection mouth C to permanent hoisting height/check valve 8 from the 3rd port e, it is large that the water capacity of the control chamber 7 of permanent hoisting height/check valve 8 becomes, the aperture of permanent hoisting height/check valve 8 diminishes, the pressure of permanent hoisting height/check valve 8 upstream cavity 9 is raise, thereby keep former setting lift H 1
When the minimizing of system water amount, the pressure rise of permanent hoisting height/check valve 8 downstream cavity 9 rises the pressure of the upstream cavity 10 of permanent hoisting height/check valve 8 thereupon.At this moment the rising water pressure of the second pressure measuring chamber b, the thrust that diaphragm 413 makes progress rises, upper valve core 414 interlock sealing gaskets 419 are moved up, make the first port c that flows through, the water yield that flows out to again the 3rd port e increases, making at last from the 3rd port e increases by the water yield of the downstream cavity 9 of interior hole path from the 3rd connection mouth C to permanent hoisting height/check valve 8, the water capacity of the control chamber 7 of permanent hoisting height/check valve 8 diminishes, it is large that the aperture of permanent hoisting height/check valve 8 becomes, make the pressure drop of permanent hoisting height/check valve 8 upstream cavity 10, thereby keep former setting lift H 1
In sum, when water pump 12 suction pressures equal zero, behind the water of the first connection mouth A inflow by water pump 12 outlet end of integrated control valve 1, be diverted to the second pressure measuring chamber b, press water makes diaphragm 413 produce upwards thrust, contend with main spring 407 downward forces, interlock upper valve core 414 moves up and down, and regulates the water flow that is flowed into by the D port, thereby regulates hydraulic control valve 8 control chambers 7 water yields, final aperture of regulating hydraulic control valve, thereby the pressure H of constant water force control valve 8 upstream cavity 10 1
3. non-return operating mode
When water pump 12 cuts out, the outlet pressure rapid drawdown of water pump 12, at this moment the hydraulic pressure of the second pressure measuring chamber b descends rapidly, and the thrust that diaphragm 413 makes progress descends rapidly, makes upper valve core 414 interlock sealing gaskets 419 mobile rapidly downwards, and the 3rd port e is cut off.The water of permanent hoisting height/check valve 8 downstream cavity 9 flows to the first needle-valve 2 through the 3rd connection mouth C by interior hole path, the other end of the first needle-valve 2 connects the entrance of the first one-way valve 3 by interior hole path, and the outlet of the first one-way valve 3 connects the control chamber 7 that the 4th connection mouth D enters into permanent hoisting height/check valve 8 by interior hole path.Permanent hoisting height/check valve 8 cuts out rapidly.
⑵ (P 1≠ 0) time:
When being not equal to zero when water pump 12 suction pressures, the present invention creatively connects the entrance of water pump 12 at the second connection mouth B, and the second connection mouth B is with the pressure P of the entrance of water pump 12 1Be incorporated into the top of diaphragm 413, make the pressure P of water pump 12 entrances 1With with main spring 407 common force actions in diaphragm 413, this pressure P with the first connection mouth A of making a concerted effort 2Contend with, interlock upper valve core 414 moves up and down, and just can produce (P 2-P 1) differential generation upper valve core 414 moves variable, thereby revise the outlet pressure variable that water pump 12 produces because of the pressure change of entrance.Therefore, in the continuous situation about changing of the pressure of water pump 12 entrances, make the outlet pressure P of water pump 2Be modified to lift (H 1=P 2-P 1), namely realize permanent lift operating mode.
In like manner, hold the pressure of pressing operating mode also can revise water pump 12 entrances and change, under setting lift parameter, work.

Claims (3)

1. the integrated control valve of permanent hoisting height/check valve, it is characterized in that it is an overall structure, the connection mouth that comprises four external pipes, be respectively the first connection mouth, the second connection mouth, the 3rd connection mouth and the 4th connection mouth, described integrated control valve comprises the first needle-valve (2), the first one-way valve (3), pilot valve (4), the second one-way valve (5) and the second needle-valve (6), described pilot valve (4) comprises three-way valve, the first pressure measuring chamber and the second pressure measuring chamber, three-way valve is subjected to the first pressure measuring chamber and the second pressure measuring chamber institute measuring pressure Collaborative Control, the first pressure measuring chamber is communicated with the second connection mouth, the second pressure measuring chamber is communicated with the first connection mouth, the first connection mouth also is communicated with an end of the second needle-valve (6), the other end of the second needle-valve (6) is communicated with the entrance of the second one-way valve (5), the outlet of the second one-way valve (5) is communicated with the first port of three-way valve, one end of the first needle-valve (2) is communicated with the 3rd connection mouth, the other end of the first needle-valve (2) is communicated with the entrance of the first one-way valve (3), the outlet of the first one-way valve (3) is communicated with the 4th connection mouth, the 4th connection mouth is communicated with the second port of three-way valve, and the 3rd connection mouth is communicated with the 3rd port of three-way valve.
2. the integrated control valve of permanent hoisting height/check valve according to claim 1, the first port that it is characterized in that three-way valve is communicated with the second port, when the difference of the hydrodynamic pressure of the hydrodynamic pressure of the second pressure measuring chamber and the first pressure measuring chamber does not reach the threshold value of setting, the 3rd port closed, when the difference of the hydrodynamic pressure of the hydrodynamic pressure of the second pressure measuring chamber and the first pressure measuring chamber reached the threshold value of setting, the first port of three-way valve, the second port were communicated with the 3rd port.
3. the integrated control valve of permanent hoisting height/check valve according to claim 2, it is characterized in that pilot valve (4) comprises the main valve stem protecting cover (401) that links to each other successively, main valve stem (403), spring capping (404), main spring (407), spring pad (410), diaphragm (413), upper valve core (414), sealing gasket (419), middle spool (420), lower valve core (421), lower valve core spring (425), the first pressure measuring chamber is arranged at the top of diaphragm (413), the second pressure measuring chamber is arranged at the below of diaphragm (413), controls the first port of three-way valve and break-make and the aperture between the 3rd port by sealing gasket (419).
CN 201220511850 2012-09-29 2012-09-29 Integrated control valve for constant jetting height and check valve Withdrawn - After Issue CN202811398U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN 201220511850 CN202811398U (en) 2012-09-29 2012-09-29 Integrated control valve for constant jetting height and check valve

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Application Number Priority Date Filing Date Title
CN 201220511850 CN202811398U (en) 2012-09-29 2012-09-29 Integrated control valve for constant jetting height and check valve

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CN202811398U true CN202811398U (en) 2013-03-20

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CN 201220511850 Withdrawn - After Issue CN202811398U (en) 2012-09-29 2012-09-29 Integrated control valve for constant jetting height and check valve

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102889217A (en) * 2012-09-29 2013-01-23 广州三业科技有限公司 Integrated control valve of constant-head/check valves

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102889217A (en) * 2012-09-29 2013-01-23 广州三业科技有限公司 Integrated control valve of constant-head/check valves

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GR01 Patent grant
AV01 Patent right actively abandoned

Granted publication date: 20130320

Effective date of abandoning: 20150128

RGAV Abandon patent right to avoid regrant