CN112112978A

CN112112978A - Pilot-operated type in-pipe pressure control valve

Info

Publication number: CN112112978A
Application number: CN202011093456.9A
Authority: CN
Inventors: 李胜强; 易方; 李涛; 孟浩龙; 王强; 郭冬磊; 武建军; 董芮寒; 曾庆丰; 陈德亮
Original assignee: Beijing Aeronautical Engineering Technology Research Center
Current assignee: Beijing Aeronautical Engineering Technology Research Center
Priority date: 2020-10-13
Filing date: 2020-10-13
Publication date: 2020-12-22

Abstract

The invention discloses a pilot-operated type pressure control valve in a pipe, which comprises an automatic control valve, a pressure control pilot valve and a venturi throttling pipe. When the oil is not added, the valve core of the automatic control valve and the main sealing ring seal the oil outlet channel of the automatic control valve; when oil is added, the valve core is jacked from the main sealing ring through the pressure of oil in the oil pipeline, oil is added into the aircraft oil tank, when the oil added into the aircraft oil tank reaches control pressure, a pressure control signal is fed back to the pressure control pilot valve through the Venturi throttle pipe, and the pressure control pilot valve and the inner part of the valve body of the automatic control valve are matched to close the valve automatically; the invention uses the oil material conveyed by the oil filling pipeline as a control power medium, simplifies the design and installation, enlarges the application range, can be used for airplane oil filling operation, is also suitable for filling oil into various oil storage (transportation) containers, is safe, reliable and convenient to use, and can effectively avoid the occurrence of oil container damage accidents caused by overpressure.

Description

Pilot-operated type in-pipe pressure control valve

Technical Field

The invention relates to a pressure control device for refueling operation, in particular to a pilot-operated type pressure control device in a pipe, which is used for pressure refueling of an aircraft fuel tank and a container.

Background

The safety requirement of airplane refueling is very strict, and the refueling pressure is an important index for ensuring the safety of airplane refueling operation. Along with the continuous increase of the oil carrying capacity and the endurance mileage of the modern large aircraft, the aircraft is required to have larger oil filling capacity, meanwhile, the ground oil filling operation time is required to be shorter, the oil filling flow is improved, the large-flow aircraft oil filling is implemented, accurate and effective oil filling pressure control measures are taken, and the method is an effective means for ensuring the rapid and safe oil supply of the aircraft.

The currently used in-pipe pressure control valves generally adopt a diaphragm type pneumatic control mode, and the mode adopts a direct control type structure of a spring plus a diaphragm or a piston. However, the inventors of the present application found that the above-mentioned techniques have at least the following problems: firstly, the service life of the diaphragm is short, the service life of the diaphragm directly influences the service life of the valve, and once the diaphragm is damaged in the refueling process, the refueling safety risk is caused; secondly, the pressure setting is finished together with observing a pressure gauge, so that the pressure setting is not intuitive and the feedback is not timely; thirdly, the method has very high requirement on the pressure control precision of the air source and cannot be used on equipment without the air source.

Disclosure of Invention

In view of the above, the present invention provides a pilot-operated type in-pipe pressure control valve, which adopts a spool pilot control mode, and automatically controls the opening and closing degree of the valve by the front and rear pressure differences of a sliding spool, thereby realizing accurate pressure control. In addition, when the sealing ring of the inner sleeve of the valve is damaged, the valve can be automatically closed, and the zero error of the control of the pressure in the pipe is ensured. When the valve is closed, if the pressure of the oil filling pipe section in the valve is abnormally increased, the overpressure oil sealed from the valve to the oil filling gun pipe section can overflow to the oil tank through the pressure control pilot valve, so that the safety of an oil filling pipeline and oil receiving equipment is protected to the maximum extent.

The invention provides a pilot-operated type pressure control valve in a pipe, which comprises an automatic control valve, a pressure control pilot valve and a venturi throttling pipe;

wherein the automatic control valve includes: the valve body, the inside first accommodation space that has of valve body, the valve body has: an oil inlet end surface to which an oil filling pipe is connected, fluid flowing from the oil filling pipe into the oil inlet end surface; the oil outlet end surface is connected with a flow stabilizing pipe, and fluid flows out of the oil outlet end surface and flows into the flow stabilizing pipe; the end face of the control oil port is connected with a pressure control pilot valve; the valve core can slide in the first accommodating space along the axial direction; the valve body is provided with a first accommodating space, the valve body is provided with a valve core, the valve core is arranged in the first accommodating space, and the valve core is provided with a first end and a second end;

the pressure control pilot valve with automatic control valve is in control hydraulic fluid port terminal surface department is connected, the pressure control pilot valve includes: the guide valve body is internally provided with a second accommodating space; the guide valve core is arranged in the second accommodating space; the pilot valve spring is arranged in the second accommodating space, one end of the pilot valve spring is fixedly connected to the pilot valve body, and the other end of the pilot valve spring is fixedly connected to the pilot valve core; the adjusting handle is used for adjusting the spring force of the pilot valve spring and setting a pressure limiting value;

a venturi restriction, comprising: a venturi throttle body having: the first end surface is connected with the flow stabilizing pipe, and fluid flows into the first end surface from the flow stabilizing pipe; a second end face connected to the filler tube, fluid flowing out of the second end face and into the filler tube; the communicating pipe is connected between the guide valve core and the Venturi throttle pipe, pressure is taken from the Venturi throttle pipe and is transmitted to the guide valve core through the communicating pipe, and the pressure value transmitted to the guide valve core through the communicating pipe is influenced by the speed change of fluid; the contraction pipe is connected between the flow stabilizing pipe and the Venturi throttle pipe body; a diffuser connected between the filler tube and the venturi throttle body; the minimum hole diameter of the end, close to each other, of the contraction pipe and the diffusion pipe forms a throat diameter, and fluid flows in from the contraction pipe and flows out from the diffusion pipe;

the pilot valve core slides axially in the second accommodating space under the combined action of the spring force of the pilot valve spring and the pressure of the communicating pipe, the flow direction of fluid at the end face of the control oil port is controlled by the axial sliding direction of the pilot valve core, so that the fluid pressure of the fluid in the first accommodating space to the valve core is controlled, and the valve core slides axially in the first accommodating space under the combined action of the spring force of the return spring and the fluid pressure to control the opening degree of a fluid channel from the end face of the oil outlet to the flow stabilizing pipe.

As a further improvement of the embodiment of the present invention, the valve body further includes: a housing; the inner container is arranged in the shell and is connected with the shell into a whole; the guide sleeve is fixed inside the valve body and is tightly connected with the inner container of the valve body to form a valve inner sleeve; the valve core slides in the valve inner sleeve; the guide sleeve is provided with a sleeve central hole, and one end of the valve core can slide through the sleeve central hole.

As a further improvement of the embodiment of the invention, a front cavity is formed between one end of the outer shell close to the oil inlet end face and the valve inner sleeve; a middle cavity is formed between the valve core and the inner container, the front cavity is communicated with the pressure control pilot valve at the end face of the control oil port, and the middle cavity is communicated with the pressure control pilot valve at the end face of the control oil port; a first control fluid passage is provided from the front cavity to the middle cavity, and the path is the front cavity → the control oil port end face → the pressure control pilot valve → the control oil port end face → the middle cavity; a second control fluid passage is arranged from the middle cavity to the pressure control pilot valve, and the path is the middle cavity → the control oil port end face → the pressure control pilot valve;

the guide valve core slides along the axial direction to control the opening and closing degree of the first control fluid passage and the second control fluid passage; a rear cavity is formed between one end of the outer shell, close to the flow stabilizing pipe, and the valve inner sleeve, and a one-way main fluid passage is formed from the front cavity to the rear cavity; an acting force cavity is formed between the valve core and the guide sleeve, a drainage hole is formed in the guide sleeve, and the front cavity fluid enters the acting force cavity through the drainage hole; the fluid pressure in the middle cavity and the acting cavity acts on the valve core to control the axial sliding direction of the valve core, and further control the opening degree of the one-way main fluid passage.

As a further improvement of the embodiment of the present invention, the manner in which the pilot spool slides in the axial direction to control the opening degree of the first control fluid passage and the second control fluid passage is: when the pressure in the pipe exceeds the pressure limiting value, the guide valve core slides axially towards a first direction to control the first control fluid passage to be opened to be fully opened, meanwhile, the second control fluid passage is closed to be closed, the fluid in the middle cavity is increased, and the valve core is pushed to slide axially to be closed until the one-way main fluid passage is closed; when the pressure in the pipe is smaller than the pressure limiting value, the guide valve core slides axially towards a second direction to control the first control fluid passage to be closed until the first control fluid passage is closed, meanwhile, the second control fluid passage is opened to be fully opened, the fluid in the middle cavity is reduced, and the reset spring pulls the valve core to slide axially to be opened until the one-way main fluid passage is fully opened; the first direction is opposite to the second direction.

As a further improvement of the embodiment of the present invention, the pilot valve body has an oil inlet and an oil outlet, and the automatic control valve has a front oil hole and a middle oil hole; the oil inlet is communicated with the front oil hole on the end face of the control oil port, and the oil inlet and the oil outlet are communicated with the middle oil hole on the end face of the control oil port; when the guide valve core slides along the axial direction to open the first control fluid passage, the fluid in the front cavity flows into the pressure control pilot valve through the front oil hole and the oil inlet, and then enters the middle cavity through the oil inlet and the oil outlet and the middle oil hole; when the guide valve core slides to open a bidirectional control fluid passage from the middle cavity to the pressure control pilot valve, the fluid in the middle cavity flows into the pressure control pilot valve through the middle oil hole and the oil inlet and outlet.

As a further improvement of the embodiment of the present invention, the pressure control pilot valve further includes a push rod, the push rod is disposed at one end of the pilot valve body close to the adjusting handle, and the push rod can move axially inside the pilot valve body by rotating the adjusting handle.

As a further improvement of the embodiment of the present invention, a limit stopper is attached to an adjustment handle of the pressure control pilot valve to limit a set rotation angle range of the adjustment handle.

As a further improvement of the embodiment of the invention, a valve inner sleeve sealing ring is arranged at the joint of the guide sleeve and the inner container.

The embodiment of the invention automatically controls the opening and closing degree of the valve by the axial sliding caused by the front and back pressure difference applied to the valve core of the pressure control pilot valve, thereby realizing accurate pressure control.

The foregoing description is only an overview of the technical solutions of the present invention, and the following detailed description of the present invention is provided to enable the technical means of the present invention to be more clearly understood, and to enable the above and other objects, features, and advantages of the present invention to be more clearly understood.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

FIG. 1 is a schematic diagram of a pilot-operated in-line pressure control valve according to an embodiment of the present invention;

FIG. 2 is one of the components of a pilot-operated in-line pressure control valve provided by an embodiment of the present invention: the pressure control pilot valve is structurally schematic.

Fig. 3 is a top view of a pilot-operated in-line pressure control valve according to an embodiment of the present invention.

FIG. 4 is one of the components of a pilot-operated in-line pressure control valve provided by embodiments of the present invention: the structure schematic diagram of the pilot valve core of the pressure control pilot valve.

FIG. 5 is one of the components of a pilot-operated in-line pressure control valve provided in an embodiment of the present invention: the cross-section of the pilot valve core of the pressure control pilot valve is schematic.

FIG. 6 is one of the components of a pilot-operated in-line pressure control valve provided by embodiments of the present invention: a top view of the venturi restriction.

Fig. 7 is a pressure-rated fueling state diagram for a pilot-operated in-line pressure control valve according to an embodiment of the present invention.

Fig. 8 is a diagram illustrating an automatic closing state of a top-up valve of a pilot-operated in-line pressure control valve according to an embodiment of the present invention.

Fig. 9 is a diagram illustrating a state in which a pilot operated in-line pressure control valve according to an embodiment of the present invention is further opened when an expansion pressure is generated.

In the figure:

i, automatically controlling a valve; II, controlling a pilot valve by pressure; III a venturi restriction; a P force chamber; p1 anterior chamber; a P2 lumen; p3 posterior chamber; p4 throat pressure; p5 fueling pressure; 1, a valve body; 1a oil inlet end surface; 1b oil outlet end face; 1c controlling the end face of the oil port; 1d of a shell; 1e, an inner container; 1f central hole of the liner; 1g shell center hole; 1i front oil port; 1j middle oil port; 2, a return spring; 3, a guide sleeve; 3a, sleeving a first central hole; 3b, sleeving a second central hole; 3c, a first drainage hole; 4, a valve core; 4a, a core column surface I; 4b sealing the end face; 4c core hole end face; 4d, the end surface of a core cylindrical surface II and a core ring 4 e; 5, pressing a ring; 6, a main sealing ring; 7O-shaped rubber sealing rings; 8, a flange; 9, sealing rings; 10 a fastener; 11a pilot valve body; 11a screw hole; 11b an overflow port; 11c a central hole; 11d, forming a first annular groove; 11e, an inner ring groove II; 11f, an inner ring groove III; 11g of an inner ring groove IV; 11h left end face of the body; 11i, the end face of the counter bore of the body; 11j end holes; an 11k oil inlet; an oil inlet and an oil outlet of 11 m; 12a pilot valve core; 12a cylindrical surface; 12b an outer ring groove I; 12c an outer ring groove II; 12d, an outer ring groove III; 12e outer ring groove four; 12f a channel; 12g of a drainage hole; balancing holes for 12 h; 12i core flange; 12j wedge-shaped front throttle notch; a 12k wedge-shaped rear throttling notch; a drainage hole II of 12 m; 12n pressure sensing ends; 13 a pilot valve spring; 14, a mandril; 14a rod groove; 14b a rod end face; 14c a left end face of the rod; 15 adjusting the stud; 15a rectangular external thread; 15b post center hole; 15c a terminating end; 15d column flange; 16 limiting stops; 16a stop center hole; 17 adjusting the handle; 17a rectangular internal thread; 17b, the bottom end of the hole; 17c a pressure scale zone; 18 connecting a nut; 18a nut holes; 19a pipe joint; 19a pressure sensing chamber; 20 flow stabilizing tubes; 20a end face I; a 21 venturi throttle body; 21a internal thread; 21b a central ring groove; 21c a connector screw hole; 21d trench through holes; 22a shrink tube; 22a throat diameter; 22b throat gap; 23 a diffuser tube; 24 communicating pipes; 25, an overflow pipe; 26 oil tanks; 27a filler tube; 27a end face II; 28 a fuel fill fitting; 29 gauge.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

The invention provides a pilot-operated type pipe internal pressure control valve, which realizes accurate and automatic control of pipe internal pressure in a pilot control mode of a slide valve and realizes a fault self-protection function.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram illustrating a pilot-operated type internal pipe pressure control valve according to an embodiment of the present invention.

Fig. 3 illustrates a top view of a pilot-operated in-line pressure control valve provided by an embodiment of the present invention.

As shown in fig. 1 and 3, the main components of the present invention include: an automatic control valve I, a pressure control pilot valve II and a Venturi throttle pipe III;

1. automatic control valve I

The automatic control valve I comprises a valve body 1, a return spring 2, a guide sleeve 3, a valve core 4, a pressure ring 5, a main sealing ring 6, a flange 8 and a sealing ring 9.

An oil inlet end face 1a of the valve body 1 is connected to one end of a pipeline, an oil outlet end face 1b is connected to one end of a flow stabilizing pipe 20, and a control oil port end face 1c is connected to one end of a pressure control pilot valve II.

The valve body 1 comprises a shell 1d and an inner container 1e, wherein the inner container 1e is arranged inside the shell 1d and connected with the shell 1 into a whole, and is close to the end face 1a of the oil inlet. The guide sleeve 3 is arranged at the end of a sealing oil port 6a of the shell 1d and is mutually matched with the liner 1e in a sealing way in a liner central hole 1f and a shell central hole 1g, and the guide sleeve 3 is provided with a sleeve central hole two 3b which can enable a sealing end 4b of the valve core 4 to pass through at the end of the sealing oil port 6 a; the valve core 4 is sleeved in a sleeve center hole I3 a and a sleeve center hole II 3b of the guide sleeve 3, and the valve core 4 comprises a sealing end 4b with a sealing oil port 6a, a core column surface I4 a and a core column surface II 4d which are tightly contacted with the guide sleeve 3 and can relatively slide in the guide sleeve 3; the flange 8 is fixed on the outer shell 1d of the valve body 1 at the end of the sealed oil port 6a, and the guide sleeve 3 is tightly pressed on the inner container 1e by the flange 8 and forms a valve inner sleeve together with the inner container 1 e;

a front cavity P1 is formed between the outer shell 1d of the valve body 1 and the valve inner sleeve, a middle cavity P2 is formed between the inner part of the valve core 4 and the valve inner sleeve, and a rear cavity P3 is formed between the sealing end surface 4b of the valve core 4 and one side connected with the flow stabilizing pipe 20. The front cavity P1 is connected with the control port end face 1c through a front oil hole 1f, the middle cavity P2 is connected with the control port end face 1c through a middle oil hole 1i, a main sealing ring 6 is arranged at the oil outlet 6a of the valve body, and the main sealing ring 6 is matched with the sealing end face 4b of the valve core 4 to control the opening degree of the front cavity P1 and the rear cavity P3. The middle cavity P2 is provided with a return spring 2, one end of the return spring 2 is abutted against the spring seat hole 1h of the inner container 1e, and the other end is abutted against the core hole end face 4c of the valve core 4 abutted against the sealing end face 4 b.

A flange 8 is fixed on a housing 1d of the valve body 1 at the end of the sealing oil port 6a, a compression ring 5 is compressed between the flange 8 and the guide sleeve 3, a main sealing ring 6 is compressed between the compression ring 5 and the flange 8, an O-shaped rubber sealing ring 7 for preventing the automatic control valve from oil leakage is arranged at the contact part of the compression ring 5, the valve body 1 and the flange 8, and the O-shaped rubber sealing ring 7 is arranged to better prevent the automatic control valve from oil leakage, so that the pressure control valve in the pilot-operated pipe is safer and more stable.

The joint of the guide sleeve 3 and the inner container 1e is provided with a valve inner sleeve sealing ring 9. The front cavity P1 and the middle cavity P2 can be better isolated by arranging the valve inner sleeve sealing ring 9, so that the automatic control valve I is more stable and reliable.

2. Pressure control pilot valve II

Fig. 2 shows a schematic of the structure of the pressure controlled pilot valve II.

Fig. 4 and 5 show a structural view of the pilot valve spool 12 of the pressure control pilot valve II.

As can be seen from fig. 2, 4 and 5, the pressure control pilot valve II includes a pilot valve body 11, a pilot valve core 12, a pilot valve spring 13, a push rod 14, an adjusting stud 15, a limit stop 16, an adjusting handle 17, and a connecting nut 18. The pilot valve core 12 is provided with a pressure sensing end 12n, and an adjusting handle 17 is connected with the pilot valve body 11 to adjust the spring force of the pilot valve spring 13; the pilot valve body 12 slides inside the pilot valve body 11 under the influence of the pressure of the pilot valve spring 13 and the pressure sensing end 12 n.

The nipple 11a of the pilot valve body 11 is connected to the pipe joint 19, and the overflow nipple 11b is connected to the overflow pipe 25. The pilot valve body 11 is provided with an inner annular groove 11d, an inner annular groove 11e, an inner annular groove three 11f, and an inner annular groove four 11g in the center hole 11c, respectively. The pilot valve body 11 is provided with an oil inlet 11k and an oil outlet 11m, the oil inlet 11k is communicated with the second inner annular groove 11e, and the oil outlet 11m is connected with the third inner annular groove 11 f. The cylindrical surface 12a of the guide valve core 12 is respectively provided with an outer ring groove I12 b, an outer ring groove II 12c, an outer ring groove III 12d and an outer ring groove IV 12e, and the boundary area between the two sides of the outer ring groove III 12d and the cylindrical surface 12a is respectively provided with a wedge-shaped front throttling notch 12j and a wedge-shaped rear throttling notch 12 k. The guide valve core 12 is provided with a drainage hole 12m and communicated with a drainage hole 12g in the outer groove III 12 d. The pilot valve core 12 is provided with a balance hole 12h, and the balance hole 12h and the end face 12i of the core flange. The pressure sensing end 12n of the pilot spool 12 faces the pressure sensing chamber 19 a.

When the adjusting bolt is installed, the adjusting bolt 15 is installed in a nut hole 18a of a connecting nut 18 in a sliding mode, the end of a rectangular thread 15a of the adjusting bolt 15 is screwed into a rectangular threaded hole 17a of an adjusting handle 17 which is firstly provided with a limiting stop 16, the adjusting bolt 15 and the adjusting handle 17 are continuously screwed until the small end of the limiting stop 16 is extruded into a central hole 15b of a column of the adjusting bolt 15, an ejector rod 14 is installed in the central hole 15b of the column of the adjusting bolt 15 and the central hole 16a of the limiting stop 16 in a sliding mode, the limiting stop 16 limits the range of the set rotation angle of the adjusting handle 17 to be not more than one circle, and a pressure scale area 17c is arranged on the; the pilot valve spring 13 is arranged in a central hole 15b of the column of the adjusting stud 15, one end of the pilot valve spring 13 abuts against the end face 14b of the post rod 14, the other end abuts against a core flange 12i of the pilot valve core 12, a spigot end 15c of the adjusting stud 15 is slidably arranged in an end hole 11j of the pilot valve body 11, a connecting nut 18 presses a left end face 11h of a column flange 15d of the adjusting stud 15 against the pilot valve body 11, and the end face of the core flange 12i is attached to a counter bore end face 11i under the action of the spring force on the core flange 12 i; the left end surface 14c of the ejector rod 14 abuts against the bottom end 17b of the hole of the adjusting handle 17 and correspondingly moves along the axial direction along with the rotation and adjustment of the adjusting handle 17; the fastener 10 tightly connects the pressure control pilot valve II with the automatic control valve I at the control end face 1 c.

The push rod 14 is provided with an annular groove 14a, and the end faces of the annular groove 14a, which are contacted with the end face of the valve guide body 11, are provided with O-shaped rubber sealing rings 7 for preventing oil leakage. The O-shaped rubber sealing ring 7 can be arranged to better prevent the pressure control pilot valve II from leaking oil, so that the pressure control pilot valve II is safer and more stable.

3. Venturi throttle pipe III

Figure 6 shows a top view of the venturi restriction III.

As shown in fig. 1 and 6, the venturi restriction III includes a venturi restriction body 21, a contraction tube 22, and a diffuser 23. The venturi throttle body 21 has a central threaded bore 21a, a central annular groove 21b and a radial threaded bore 21c of the attached nipple 19, the central annular groove 21b communicating with the radial threaded bore 21c through a fluted through bore 21 d. The contraction pipe 22 is screwed into the central threaded hole 21a of the venturi throttle body 21 on the side close to the end surface 20a, and the diffuser pipe 23 is screwed into the central threaded hole 21a of the venturi throttle body 21 on the side close to the end surface 27 a. The diameter of the minimum hole at the end close to the contraction pipe 22 and the diffusion pipe 23 forms a throat diameter 22a, a small gap is arranged at the end close to the contraction pipe 22 and the diffusion pipe 23 to form a throat gap 22b, and the throat gap 22b is communicated with the central annular groove 21 b.

A communicating pipe 24 is arranged between the pipe joint 19 of the Venturi throttle pipe III and the pipe joint 19 of the pressure control pilot valve II, the communicating pipe 24 transmits a Venturi throttle pipe III throat pressure P4 signal to a pressure sensing cavity 19a of the pilot valve core 12, and a pressure gauge 29 displays the throat pressure P4. The throat pressure P4 simulates the pressure P5 at the filler neck 28 at the end of the filler tube 27, and the throat pressure P4 can be matched to the filler pressure P5 by sizing the throat diameter 22 a.

The venturi throttling pipe III is connected with the flow stabilizing pipe 20 and the oil filling pipe 27 through fasteners 10, and an O-shaped sealing ring for preventing oil leakage is arranged between two end faces I20 a and II 27a of the venturi throttling pipe III. The O-shaped rubber sealing ring 7 can better prevent oil leakage at the joint of the Venturi throttle pipe III, so that the Venturi throttle pipe III is safer and more stable.

4. Connection relation among automatic control valve I, pressure control pilot valve II and Venturi throttle pipe III

The front oil port 1I on the valve body 1 of the automatic control valve I is positioned in a front cavity P1 and is tightly connected with the oil inlet 11k on the valve body 11 of the pressure control pilot valve II, the oil inlet 11k is communicated with the inner annular groove II 11e, the inner annular groove II 11e is communicated with the wedge-shaped front throttling notch 12j of the guide valve core 12, the wedge-shaped front throttling notch 12j is communicated with the oil inlet and outlet 11m on the valve body 11, the oil inlet and outlet 11m is communicated with the middle oil port 1j on the valve body 1 of the automatic control valve I, and the middle oil port 1j is positioned in a middle cavity P1 of the. When the pilot valve spool 12 slides inside the pilot valve body 11 so that the wedge-shaped front throttling notch 12j is closed, the fluid passage from the front chamber P1 of the automatic control valve I to the middle chamber P2 is closed.

The middle oil port 1j on the valve body 1 of the automatic control valve I is positioned in the front cavity P2 and is tightly connected with the oil inlet and outlet port 11m on the valve body 11 of the pressure control pilot valve II, the oil inlet and outlet port 11m is communicated with the inner annular groove III 11f, the inner annular groove III 11f is communicated with the wedge-shaped rear throttling notch 12k of the guide valve core 12, the wedge-shaped rear throttling notch 12k is communicated with the drainage hole II 12m on the guide valve core 12, the drainage hole II 12m is communicated with the drainage hole 12g in the outer groove III 12d, and the drainage hole 12g is communicated with the pipe joint 19. When the pilot valve spool 12 slides inside the pilot valve body 11 so that the wedge shaped back throttle notch 12k is closed, the fluid passage from the middle chamber P2 of the automatic control valve I to the venturi orifice III is closed.

Form power chamber P between core face of cylinder 4a of case 4 and the uide bushing 3, power chamber P and antechamber P1 pass through drainage hole 3c intercommunication on the uide bushing 3, when the fluid pressure in antechamber P1 increases, the fluid that gets into power chamber P through drainage hole 3 increases gradually, the effort that produces reset spring 2 to case 4 is resisted to the effort that case 4 produced, crowd the fluid in lumen P2 to pressure control pilot valve II, case 4 deviates from the sealed hydraulic fluid port 6a end of shell 1d and slides simultaneously, antechamber P1 increases to the flow channel of back chamber P3.

And a fastening piece 10 is arranged between the automatic control valve I and the pressure control pilot valve II for connection, and O-shaped rubber sealing rings 7 for preventing oil leakage are arranged at the end face 1b of the oil outlet and the end face 1c of the control oil port. The O-shaped rubber sealing ring 7 can better prevent oil leakage at the joint of the automatic control valve I and the pressure control pilot valve II, so that the pilot type in-pipe pressure control valve is safer and more stable.

The working states of the pilot-operated type pressure control valve in the pipe provided by the embodiment of the invention comprise 5 types: the sealing ring 9 in the inner sleeve of the valve is damaged in the initial state, the valve is opened, the oil filling valve is automatically closed, the oil filling pipe section expands oil in the valve closing state and the valve opening state. These 5 operating states are described in detail below.

1. Initial state

Before oiling, an adjusting handle 17 of the pressure control pilot valve II is provided with an in-pipe pressure limiting value.

At this time, the front cavity P1 of the automatic control valve I has no oil filling pressure, the valve core 4 of the automatic control valve I contacts with the main seal ring 6 under the thrust of the return spring 2 to seal the oil outlet 6a, and the automatic control valve I is in a closed state. The pilot valve core 12 of the pressure control pilot valve II slides in the pilot valve body hole to the pipe joint 19 side of the pressure control pilot valve II under the thrust of the pilot valve spring 13, at this time, the fluid passage of the front chamber P1 of the automatic control valve I into the middle chamber P2 is closed, and the fluid passage of the middle chamber P2 to the downstream line is opened. The fluid passage of the downstream pipeline means that fluid passes through an intermediate oil port 1I of the automatic control valve I, an oil inlet and outlet 11m of the pilot valve body 11, a wedge-shaped rear throttling notch 12k of the pilot valve core 12, a second drainage hole 12m, a pipe joint 19, a communicating pipe 24 and is extruded into the oil filling pipe 27 until a throat end gap 22b at the throat diameter 22a of the Venturi throttle pipe III.

2. Valve opening

When oil is added, pressurized fluid enters a front cavity P1 of the automatic control valve I, the pressure of the pressurized fluid in the front cavity P1 is introduced into a force cavity P at the right end of the valve core 4 through a first drainage hole 3c on the guide sleeve 3, the fluid thrust acting on the end face 4e of the core ring at the middle section of the valve core 4 overcomes the spring force of a return spring 2 which is propped against the end face 4c of the core hole of the valve core 4, so that the fluid in the middle cavity P2 of the automatic control valve I is extruded into the oil adding pipe 27 through an intermediate oil port 1j of the valve body 1, an oil inlet and outlet port 11m of the pilot valve body 11, a wedge-shaped rear throttling notch 12k of the pilot valve core 12, a second drainage hole 12m, a pipe joint 19, a communicating pipe 24 and a throat end gap 22b at the throat diameter 22a of the Venturi throttle pipe III.

3. Automatic closing of oil filling valve

Fig. 8 is a diagram illustrating an automatic closing state of a top-up valve of a pilot-operated in-pipe pressure control valve according to an embodiment of the present invention.

When the pressure at the pipe end, namely the throat pressure of the venturi throttling pipe III, is lower than the set pressure of the pressure control pilot valve II, the acting force of the pressure sensing end 12n of the pilot valve core 12 is lower than the spring force set on the flange 12i of the left end core of the pilot valve core 12 by the adjusting handle 17, and the pilot valve core 12 still keeps left biased, namely: the opening of the automatic control valve I is maintained. Along with the oil tank is gradually filled, the oil filling pressure at the oil filling joint gradually rises, the throat pressure of the Venturi throttle pipe III also rises, the acting force of the pressure sensing end 12n of the guide valve core 12 also increases, and the guide valve core 12 moves to the left, namely: the pilot valve core 12 gradually opens the large wedge-shaped front throttling notch 12j and closes the small wedge-shaped rear throttling notch 12k, so that the fluid in the front cavity P1 is increased to enter the fluid volume in the middle cavity P2, meanwhile, the elimination amount of the fluid passage of the middle cavity P2 to a downstream pipeline is reduced, the valve core 4 of the automatic control valve I is moved to the right, the oil outlet 6a is closed, and the oil filling pressure overpressure is avoided; if the oil tank is full, the flow rate of the fluid is zero, at this time, when the pressure at the rear end of the automatic control valve I rises to the spring force set on the flange 12I of the left end core of the pilot valve core 12 on the adjusting handle 17 of the pressure control pilot valve II, the pilot valve core 12 immediately deflects left, the wedge-shaped front throttling notch 12j is opened, and the wedge-shaped rear throttling notch 12k is closed, namely: the fluid in the front cavity P1 rapidly enters the middle cavity P2 of the automatic control valve I, and as the pilot valve core 12 closes the wedge-shaped rear throttling notch 12k, the valve core 4 closes the oil outlet 6a under the combined action of the fluid pressure and the spring force of the return spring 2, so that the automatic control of the pressure in the pipe at the rear end of the pilot-operated type pipe internal pressure control valve is realized.

4. Oil filling pipe section expansion oil in valve closing state

When the valve is in a closed state after the oil filling function is finished, the pressure of the oil filling pipe section is abnormally increased due to some reason, and in order to protect the safety of an oil filling pipeline, overpressure oil sealed between the valve and the oil filling joint section can pass through the drain hole 12g of the guide valve core 12, the overflow port 11b of the guide valve body 11 and the overflow pipe 25 to reach the oil tank 26.

5. Damage to the valve inner sleeve sealing ring 9 in the open state

When the sealing ring 9 of the valve inner sleeve is damaged, the valve can be automatically closed, and the zero error of the pressure control in the pipe is ensured.

When the valve inner sleeve sealing ring 9 (a vulnerable part) is damaged, namely: the front valve cavity P1 and the middle cavity P2 are isolated and sealed to fail, pressurized oil in the front valve cavity P1 directly enters the middle valve cavity P2, the oil inlet amount far exceeds the oil outlet amount of the pressure control pilot valve II, at the moment, the valve core 4 of the automatic control valve I contacts with the main sealing ring 6 under the thrust action of the return spring 2 to seal the oil outlet 6a, and the automatic control valve I is closed.

In addition, the main sealing ring 6 of the pilot-operated type pipe internal pressure control valve can be made of nylon or Teflon (PTFE) or other materials with high strength which can be suitable for being made into the sealing ring, and other sealing rings on the pilot-operated type pipe internal pressure control valve can be made of rubber materials.

In the description provided herein, numerous specific details are set forth. It is understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the invention and aiding in the understanding of one or more of the various inventive aspects. However, the disclosed method should not be interpreted as reflecting an intention that: that the invention as claimed requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments may be used in any combination.

Claims

1. A pilot-operated in-pipe pressure control valve, comprising:

an automatic control valve comprising:

the valve body, the inside first accommodation space that has of valve body, the valve body has: an oil inlet end surface to which an oil filling pipe is connected, fluid flowing from the oil filling pipe into the oil inlet end surface; the oil outlet end surface is connected with a flow stabilizing pipe, and fluid flows out of the oil outlet end surface and flows into the flow stabilizing pipe; the end face of the control oil port is connected with a pressure control pilot valve;

the valve core can slide in the first accommodating space along the axial direction;

the reset spring is arranged in the first accommodating space, one end of the reset spring is fixedly connected to the valve body, and the other end of the reset spring is fixedly connected to the valve core;

the pressure control pilot valve with the automatic control valve is in control hydraulic fluid port terminal surface department is connected, the pressure control pilot valve includes:

the guide valve body is internally provided with a second accommodating space;

the guide valve core is arranged in the second accommodating space;

the pilot valve spring is arranged in the second accommodating space, one end of the pilot valve spring is fixedly connected to the pilot valve body, and the other end of the pilot valve spring is fixedly connected to the pilot valve core;

the adjusting handle is used for adjusting the spring force of the pilot valve spring and setting a pressure limiting value; a venturi restriction, comprising:

a venturi throttle body having: the first end surface is connected with the flow stabilizing pipe, and fluid flows into the first end surface from the flow stabilizing pipe; a second end face connected to the filler tube, fluid flowing out of the second end face and into the filler tube;

the communicating pipe is connected between the guide valve core and the Venturi throttle pipe, pressure is taken from the Venturi throttle pipe and is transmitted to the guide valve core through the communicating pipe, and the pressure value transmitted to the guide valve core through the communicating pipe is influenced by the speed change of fluid;

the contraction pipe is connected between the flow stabilizing pipe and the Venturi throttle pipe body;

a diffuser connected between the filler tube and the venturi throttle body;

the minimum hole diameter of the end, close to each other, of the contraction pipe and the diffusion pipe forms a throat diameter, and fluid flows in from the contraction pipe and flows out from the diffusion pipe;

2. A pilot operated in-line pressure control valve as defined in claim 1, wherein:

the valve body further includes:

a housing;

the inner container is arranged in the shell and is connected with the shell into a whole;

the guide sleeve is fixed inside the valve body and is tightly connected with the inner container of the valve body to form a valve inner sleeve; the valve core slides in the valve inner sleeve; the guide sleeve is provided with a sleeve central hole, and one end of the valve core can slide through the sleeve central hole.

3. A pilot operated in-line pressure control valve as defined in claim 2, wherein:

a front cavity is formed between one end of the outer shell, which is close to the oil inlet end face, and the valve inner sleeve; a middle cavity is formed between the valve core and the inner container, the front cavity is communicated with the pressure control pilot valve at the end face of the control oil port, and the middle cavity is communicated with the pressure control pilot valve at the end face of the control oil port;

a first control fluid passage is provided from the front cavity to the middle cavity, and the path is the front cavity → the control oil port end face → the pressure control pilot valve → the control oil port end face → the middle cavity;

a second control fluid passage is arranged from the middle cavity to the pressure control pilot valve, and the path is the middle cavity → the control oil port end face → the pressure control pilot valve;

the guide valve core slides along the axial direction to control the opening and closing degree of the first control fluid passage and the second control fluid passage;

a rear cavity is formed between one end of the outer shell, close to the flow stabilizing pipe, and the valve inner sleeve, and a one-way main fluid passage is formed from the front cavity to the rear cavity;

a force cavity is formed between the valve core and the guide sleeve,

the guide sleeve is provided with drainage holes, the front cavity fluid enters the acting cavity through the drainage holes,

the fluid pressure in the middle cavity and the acting cavity acts on the valve core to control the axial sliding direction of the valve core, and further control the opening degree of the one-way main fluid passage.

4. A pilot operated in-line pressure control valve as defined in claim 3, wherein: the mode of the guide valve core sliding along the axial direction to control the opening degree of the first control fluid passage and the second control fluid passage is as follows: when the pressure in the pipe exceeds the pressure limiting value, the guide valve core slides axially towards a first direction to control the first control fluid passage to be opened to be fully opened, meanwhile, the second control fluid passage is closed to be closed, the fluid in the middle cavity is increased, and the valve core is pushed to slide axially to be closed until the one-way main fluid passage is closed; when the pressure in the pipe is smaller than the pressure limiting value, the guide valve core slides axially towards a second direction to control the first control fluid passage to be closed until the first control fluid passage is closed, meanwhile, the second control fluid passage is opened to be fully opened, the fluid in the middle cavity is reduced, and the reset spring pulls the valve core to slide axially to be opened until the one-way main fluid passage is fully opened; the first direction is opposite to the second direction.

5. A pilot operated in-line pressure control valve as defined in claim 4, wherein: the automatic control valve is provided with a front oil hole and a middle oil hole; the oil inlet is communicated with the front oil hole on the end face of the control oil port, and the oil inlet and the oil outlet are communicated with the middle oil hole on the end face of the control oil port; when the guide valve core slides along the axial direction to open the first control fluid passage, the fluid in the front cavity flows into the pressure control pilot valve through the front oil hole and the oil inlet, and then enters the middle cavity through the oil inlet and the oil outlet and the middle oil hole; when the guide valve core slides to open a bidirectional control fluid passage from the middle cavity to the pressure control pilot valve, the fluid in the middle cavity flows into the pressure control pilot valve through the middle oil hole and the oil inlet and outlet.

6. A pilot operated in-line pressure control valve as defined in claim 2, wherein: the pressure control pilot valve also comprises a mandril which is arranged at one end of the pilot valve body close to the adjusting handle, and the mandril can move axially in the pilot valve body by rotating the adjusting handle.

7. A pilot operated in-line pressure control valve as defined in claim 6, wherein: and a limiting stopper is arranged on an adjusting handle of the pressure control pilot valve and used for limiting the set rotation angle range of the adjusting handle.

8. A pilot operated in-pipe pressure control valve according to any one of claims 2 to 7, wherein: and a sealing ring of the valve inner sleeve is arranged at the joint of the guide sleeve and the inner container.