Pressure regulating valve for maintaining differential pressure between two fuels

Abstract

The present invention provides a pressure regulating valve for maintaining a pressure deviation of two fuels, comprising a housing; a control piston capable of sliding along the inner wall of the housing so that a first fuel chamber and a second fuel chamber are formed on both sides of the control piston in the housing, the first fuel chamber can flow through the first fuel chamber, and the second fuel chamber can flow through the second fuel chamber; an electric control stop valve, arranged at one end of the housing close to the first fuel chamber, and the first fuel is introduced into the first fuel chamber through the active opening of the electric control stop valve; and a multi-stage adjustment part, arranged between the electric control stop valve and the control piston, capable of cooperating with the control piston to perform multiple elastic actions in the first fuel chamber to balance the pressure difference between the first fuel chamber and the second fuel chamber. The present application actively cuts off the first fuel inlet, cooperates with multi-stage pressure regulation, and has a faster response, a larger adjustment range, and a more stable adjustment.

Description

Technical Field

[0001] The invention relates to an engine accessory, in particular to a pressure regulating valve for maintaining a pressure deviation between two fuels. Background Art

[0002] At present, diesel is still the main fuel for engines of heavy-duty vehicles, ships, and non-road engineering vehicles on the Chinese market. With the upgrading of my country's emission standards, natural gas, as one of the alternative fuels, has developed rapidly in the transportation field due to its good cleanliness and economy, so the sales of gas vehicles have increased year by year.

[0003] Existing natural gas engines mainly use low-pressure manifold injection technology, but their calorific value efficiency is low and the exhaust temperature is high.

[0004] To solve the above problems, HPDI technology uses dual fuel injectors to directly inject diesel and natural gas into the combustion chamber at a high pressure of 300 bar. A small amount of diesel is injected to ignite the engine, and then 95% of natural gas is injected as the main fuel to burn and do work.

[0005] In the HPDI system, the diesel and natural gas pressures must be precisely controlled. Although the electronic control technology for diesel pressure is very mature, the electronic control technology for natural gas pressure is not yet mature. Therefore, a pressure regulating valve component is added to use diesel pressure to control natural gas pressure to improve calorific value efficiency.

[0006] Since there is no mature dual-fuel pressure control valve product yet, especially when the pressure of the first fuel is too high, relying on a single mechanical structure to cut off the input of the first fuel will cause delays, slow response speed, low efficiency, risk of cut-off jamming, and insufficient stability. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention provides a pressure regulating valve for maintaining the pressure deviation of two fuels, which can realize the active control of the on-off of the first fuel, perform multi-stage adaptive adjustment according to the pressure fluctuation, realize pressure relief buffering, reduce the pressure relief frequency, and make the whole adjustment process more stable. The technical solution adopted by the present invention is:

[0008] A pressure regulating valve for maintaining a pressure difference between two fuels, comprising

[0009] case;

[0010] The control piston is capable of sliding along the inner wall of the housing, so that a first fuel cavity and a second fuel cavity are formed on both sides of the control piston in the housing, the first fuel cavity can flow through the first fuel cavity, and the second fuel cavity can flow through the second fuel cavity;

[0011] An electrically controlled stop valve is disposed at one end of the housing close to the first fuel chamber; and

[0012] The multi-stage regulating part is arranged between the electric control stop valve and the control piston, and can cooperate with the control piston to perform multiple elastic movements in the first fuel cavity to balance the pressure difference between the first fuel cavity and the second fuel cavity.

[0013] Furthermore, a first fuel conducting portion is provided at the outlet end of the electrically controlled stop valve, and the multi-stage regulating portion extends into the first fuel conducting portion.

[0014] Furthermore, the multi-stage adjustment part includes a first adjustment part and a second adjustment part;

[0015] The first regulating part is elastically connected to the second regulating part through a second elastic member; the first regulating part is arranged between the first fuel conducting part and the first fuel cavity, and is used for conducting the first fuel from the first fuel conducting part to the first fuel cavity with a variable cross section and for preliminary adjustment of the pressure difference between the first fuel cavity and the second fuel cavity;

[0016] The second regulating part is arranged in the first fuel cavity to further regulate the pressure difference between the first fuel cavity and the second fuel cavity.

[0017] Furthermore, the first regulating part includes a first regulating valve stem and a first elastic member;

[0018] The first regulating valve stem is disposed between the first fuel conducting portion and the first fuel cavity, and the first regulating valve stem can change the size of the conducting cross section between the first fuel conducting portion and the first fuel cavity by moving;

[0019] One end of the first elastic member abuts against one end of the first fuel conducting portion, and the other end abuts against the first regulating valve stem.

[0020] Furthermore, the second regulating part includes a second regulating valve stem, a second elastic member and a third elastic member;

[0021] One end of the second regulating valve stem is elastically connected to the first regulating valve stem through a second elastic member, and the first fuel can pass through the second regulating valve stem and enter the first fuel outlet;

[0022] The third elastic member abuts between the second regulating valve stem and the control piston.

[0023] Furthermore, the second regulating valve stem comprises a limiting sleeve and a valve core, the limiting sleeve is fixed in the first fuel chamber, and the valve core passes through the limiting sleeve;

[0024] The second elastic member abuts between the valve core and the first regulating valve stem.

[0025] Furthermore, a tapered transition portion is provided in the middle of the first regulating valve stem so that a conducting cross section from the first fuel conducting portion to the first fuel cavity has a variable conducting cross section.

[0026] Furthermore, a sealing block is arranged at one end of the second regulating valve stem close to the control piston.

[0027] Furthermore, the housing is provided with

[0028] a first fuel outlet, communicating with the first fuel chamber;

[0029] The first fuel pressure relief port can be connected to the first fuel chamber by controlling the movement of the piston; and

[0030] a second fuel inlet, communicating with the second fuel chamber;

[0031] A piston cavity is provided at one end of the control piston close to the first fuel cavity.

[0032] Furthermore, a sealing ring is provided on the side of the control piston and abuts against the inner wall of the housing;

[0033] The shell is provided with an end cover at one end of the second fuel cavity.

[0034] Advantages of the present invention:

[0035] An electrically controlled stop valve is provided at the inlet of the first fuel, so that the first fuel is actively cut off when the pressure of the first fuel is too high, thereby reducing the response time of the first fuel on and off and avoiding the stuck phenomenon caused by pure mechanical response;

[0036] The multi-stage adjustment part is used to perform multi-stage adjustment between the first fuel chamber and the second fuel chamber. With the variable cross-section flow mode of the first fuel, adaptive adjustment can be performed according to pressure fluctuations. The pressure adjustment range is wider and more stable. When the inlet pressure of the first fuel changes, the pressure difference between the two fuel chambers can still be maintained.

[0037] At the same time, buffering is achieved during the pressure relief process to avoid frequent pressure relief caused by pressure fluctuations and improve the efficiency of the entire pressure regulating valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the closed state of the electric control stop valve of the present invention.

[0039] Figure 2 for Figure 1 A partial enlarged view of point A in the middle.

[0040] Figure 3 This is a schematic diagram of the open state of the electronically controlled stop valve of the present invention.

[0041] In the figure: 1-housing, 2-control piston, 3-electrically controlled stop valve, 4-first regulating valve stem, 5-first elastic member, 6-limit sleeve, 7-valve core, 8-second elastic member, 9-third elastic member, 10-sealing ring, 11-end cover, 12-tightening cap, 13-sealing block, 101-first fuel chamber, 102-second fuel chamber, 103-first fuel outlet, 104-first fuel pressure relief port, 105-second fuel inlet, 106-second fuel pressure relief port, 107-closing port, 201-piston chamber, 301-first fuel conduction part, 302-first fuel inlet, 401-right-angle channel, 402, 601-accommodation space. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0043] Please see attached Figure 1-3 The present invention provides a pressure regulating valve for maintaining a pressure deviation between two fuels, comprising:

[0044] Housing 1, control piston 2, electric control stop valve 3 and multi-stage adjustment part;

[0045] The control piston 2 can slide along the inner wall of the housing 1, so that a first fuel chamber 101 and a second fuel chamber 102 are formed on both sides of the control piston 2 in the housing 1, and the first fuel can flow in the first fuel chamber 101, and the second fuel can flow in the second fuel chamber 102; the electric control stop valve 3 is arranged at one end of the housing 1 close to the first fuel chamber 101, and the first fuel is introduced into the first fuel chamber 101 through the active opening of the electric control stop valve 3; the multi-stage adjustment part is arranged between the electric control stop valve 3 and the control piston 2, and can cooperate with the control piston 2 to perform multiple stages of elastic movements in the first fuel chamber 101 to balance the pressure difference between the first fuel chamber 101 and the second fuel chamber 102;

[0046] The electrically controlled stop valve 3 is screwed and connected to the housing 1 through a tightening cap 12, so that it is convenient for disassembly and assembly.

[0047] The present application controls the movement of the second fuel pressure control piston 2 to change the pressure in the first fuel chamber 101 and the second fuel chamber 102 in the housing 1 to adjust the pressure difference between the first fuel chamber 101 and the second fuel chamber 102, so that the first fuel pressure is lower than the second fuel pressure and maintains a fixed deviation. When the pressure in the first fuel chamber 101 is too high, the electronically controlled shut-off valve 3 is actively controlled to close, instantly cutting off the supply of the first fuel, thereby achieving a rapid response in pressure regulation, saving time, and improving usage efficiency.

[0048] The housing 1 is provided with

[0049] A first fuel outlet 103 communicates with the first fuel chamber 101;

[0050] The first fuel pressure relief port 104 can be connected to the first fuel chamber 101 by controlling the movement of the piston 2;

[0051] A second fuel inlet 105 communicates with the second fuel chamber 102; and

[0052] A second fuel pressure relief port 106;

[0053] The control piston 2 has a piston cavity 201 at one end close to the first fuel cavity 101; the piston cavity 201 is used to connect the first fuel pressure relief port 104 and the first fuel cavity 101;

[0054] The first fuel and the second fuel are two different fuels, which may be gas fuel or liquid fuel, and are suitable for situations where the pressure difference between the two fuels needs to be controlled; preferably, the first fuel is gas fuel and the second fuel is liquid fuel;

[0055] Taking the first fuel as natural gas and the second fuel as diesel as an example, the first fuel outlet 103 is connected to the external gas rail, the first fuel pressure relief port 104 is connected to the external recovery device or the first fuel tank, the second fuel inlet 105 is connected to the external oil rail, and the second fuel pressure relief port 106 is connected to the external second fuel tank. The high-pressure fuel leaking into the shell 1 at the second fuel inlet 105 can also be discharged through the second fuel pressure relief port 106.

[0056] In order to save the overall occupied space, realize the flow section change of the first fuel and multi-stage pressure difference adjustment, a first fuel conducting part 301 is provided at the outlet end of the electric control stop valve 3, and the multi-stage adjustment part extends into the first fuel conducting part 301.

[0057] The multi-stage adjustment part includes a first adjustment part and a second adjustment part;

[0058] The first adjusting portion and the second adjusting portion are elastically connected via a second elastic member 8;

[0059] The first regulating part is disposed between the first fuel conducting part 301 and the first fuel chamber 101, and is used for variable cross-section conduction of the first fuel from the first fuel conducting part 301 to the first fuel chamber 101 and preliminary regulation of the pressure difference between the first fuel chamber 101 and the second fuel chamber 102;

[0060] The second regulating portion is disposed in the first fuel chamber 101 to further regulate the pressure difference between the first fuel chamber 101 and the second fuel chamber 102 .

[0061] Wherein, the first regulating part includes a first regulating valve stem 4 and a first elastic member 5;

[0062] The first regulating valve stem 4 is disposed between the first fuel conducting portion 301 and the first fuel cavity 101. The movement of the first regulating valve stem 4 can change the size of the conducting cross section between the first fuel conducting portion 301 and the first fuel cavity 101.

[0063] One end of the first elastic member 5 abuts against one end of the first fuel conducting portion 301 , and the other end abuts against the first regulating valve stem 4 ; the first elastic member 5 provides elastic force for the movement of the first regulating valve stem 4 , playing the role of buffering and returning.

[0064] In order to achieve variable cross-section conduction between the first fuel conducting portion 301 and the first fuel cavity 101, a conical transition portion is provided in the middle of the first regulating valve stem 4, so that the first fuel conducting portion 301 to the first fuel cavity 101 has a variable conduction cross-section;

[0065] As an embodiment of the present application, one end of the first fuel cavity 101 close to the first fuel conducting portion 301 is provided with a closing opening 107 matching the transition portion; the conical transition portion is used to realize a rapid reduction in the conducting cross section and then gradually reduce the conducting cross section, thereby achieving a buffering effect;

[0066] In addition, a right-angle channel 401 for the flow of the first fuel is provided on the first regulating valve stem 4. When the transition portion on the first regulating valve stem 4 completely supports the closing opening 107, the conduction cross-section is zero. When the first regulating valve stem 4 moves to a point where the conduction cross-section is not zero, the first fuel can enter the closing opening 107 through the right-angle channel 401.

[0067] Wherein, the second regulating part comprises a second regulating valve stem, a second elastic member 8 and a third elastic member 9;

[0068] One end of the second regulating valve stem is elastically connected to the first regulating valve stem 4 through the second elastic member 8, and the first fuel can pass through the second regulating valve stem and enter the first fuel outlet 103; when the second regulating valve stem contacts the control piston 2, the two can move simultaneously to change the relative space between the first fuel cavity 101 and the second fuel cavity 102;

[0069] The third elastic member 9 abuts between the second regulating valve stem and the control piston 2; the second elastic member 8 and the third elastic member 9 both play a role of buffering and returning;

[0070] Wherein, accommodation spaces 402 and 601 for hiding the second elastic member 8 are provided on the corresponding surfaces between the first regulating valve stem 4 and the second regulating valve stem, so as to reduce the occupied space of the entire multi-stage regulating part;

[0071] In the present application, the first elastic member 5, the second elastic member 8 and the third elastic member 9 are all cylindrical springs; or, in a usage environment with a smaller space, a conical spring may be used.

[0072] As an embodiment of the present application, the second regulating valve stem includes a limiting sleeve 6 and a valve core 7, the limiting sleeve 6 is fixed in the first fuel chamber 101, and the valve core 7 passes through the limiting sleeve 6; the second elastic member 8 abuts between the valve core 7 and the first regulating valve stem 4; the valve core 7 performs a linear reciprocating motion under the restriction of the limiting sleeve 6, thereby improving the motion stability of the entire regulating process;

[0073] As another embodiment of the present application, the second regulating valve stem is an integrated structure, and its side surface is in contact with the inner wall of the first fuel chamber 101 , and can also realize its linear reciprocating motion in the first fuel chamber 101 .

[0074] In order to reduce the impact between the valve core 7 and the control piston 2 and block the flow of the first fuel to the first fuel pressure relief port 104, a sealing block 13 is configured at one end of the second regulating valve stem close to the control piston 2; the sealing block 13 is a plastic block or a rubber block, which is screwed or plugged into the valve core 7.

[0075] In order to make the first fuel flow smoothly through the second regulating valve stem, at least one fuel gap hole is axially arranged on the second regulating valve stem; or, a plurality of fuel grooves for the first fuel to flow are arranged on the side of the second regulating valve stem.

[0076] In order to reduce the movement deviation during the entire adjustment process and improve the movement stability, the first regulating valve stem 4, the first elastic member 5, the limit sleeve 6, the valve core 7, the second elastic member 8 and the third elastic member 9 are all coaxially arranged with the housing 1.

[0077] In order to reduce the probability of mixing and leakage of the two fuels, a sealing ring 10 abutting against the inner wall of the housing 1 is provided on the side of the control piston 2; there may be three sealing rings 10, the first one is installed between the second fuel inlet 105 and the second fuel pressure relief port 106, the second one is installed between the second fuel pressure relief port 106 and the first fuel pressure relief port 104, and the third one is installed between the first fuel pressure relief port 104 and the first fuel cavity 101, to separate the various interfaces; or, the sealing ring 10 is an integral sealing sleeve to increase the contact area and improve the anti-leakage effect.

[0078] In order to facilitate the assembly and replacement of the internal parts of the housing 1, the housing 1 is provided with an end cover 11 at one end of the second fuel cavity 102, so that the second fuel inlet 105 can be opened on the end cover 11;

[0079] In order to further facilitate the disassembly and assembly of the end cover 11 , the end cover 11 and the housing 1 are connected by screw connection.

[0080] Working process:

[0081] like Figure 2 As shown, when the high-pressure fuel is not introduced into the second fuel inlet 105, the electric control stop valve 3 is not energized and is in a closed state, the control piston 2 contacts the end cover 11 under the action of the third elastic member 9, the valve core 7 abuts against the limit sleeve 6 under the action of the second elastic member 8, and the first regulating valve stem 4 abuts against the closing opening 107 on the housing 1 under the action of the first elastic member 5;

[0082] When high-pressure fuel is introduced into the second fuel inlet 105, the high-pressure fuel enters the second fuel chamber 102, and the control piston 2 overcomes the elastic force of the third elastic member 9 and moves under the action of the hydraulic pressure, until the control piston 2 contacts the sealing block 13 on the valve core 7, and then pushes the valve core 7 to overcome the second elastic member 8 to move, and after the valve core 7 moves to contact one end of the first regulating valve stem 4, it pushes the first regulating valve stem 4 to overcome the first elastic member 5 to move, until the other end of the first regulating valve stem 4 contacts the valve seat of the electric control stop valve 3;

[0083] The electrically controlled stop valve 3 is energized and opened, and the high-pressure first fuel enters the first fuel cavity 101 through the first fuel inlet 105, the first fuel conducting portion 301, the right-angle channel 401 on the first regulating valve stem 4, and the closing opening 107 on the shell, and enters the gas rail from the first fuel outlet 103 after passing through the limiting sleeve 6. The first elastic member 5, the second elastic member 8 and the third elastic member 9 rebound a certain distance under the action of the first fuel liquid pressure. When the pressure difference between the second fuel cavity 102 and the first fuel cavity 101 reaches the set value, the control piston 2, the first regulating valve stem 4 and the valve core 7 are stabilized in a certain open position.

[0084] When the pressure difference between the second fuel chamber 102 and the first fuel chamber 101 is less than the set value, the electric control stop valve 3 is powered off and closed, and the force balance of the control piston 2 is broken, so that the control piston 2, the first regulating valve stem 4 and the valve core 7 move toward the second fuel chamber 102, and the cross section of the transition portion on the first regulating valve stem 4 and the closing opening 107 on the housing 1 is reduced, and the pressure in the first fuel chamber 101 is reduced until the pressure difference between the second fuel chamber 102 and the first fuel chamber 101 reaches the set value again;

[0085] If the pressure difference cannot reach the set value even if the flow area of ​​the first fuel is reduced, the control piston 2, the first regulating valve stem 4 and the valve core 7 move in the direction of the second fuel chamber 102 and stop when the regulating valve stem 4 abuts against the closing end 107 on the shell. The first fuel inlet channel is completely closed, and the control piston 2 and the valve core 7 continue to move and stop when the valve core 7 abuts against the limit sleeve 6. The control piston 2 continues to move until the piston chamber 201 on the control piston 2 connects the first fuel chamber 101 and the first fuel pressure relief port 104, and the first fuel chamber 101 releases pressure through the first fuel pressure relief port 104, and the pressure in the first fuel chamber 101 drops until the pressure difference between the second fuel chamber 102 and the first fuel chamber 101 reaches the set value again.

[0086] When the pressure difference between the second fuel chamber 102 and the first fuel chamber 101 is greater than the set value, the solenoid valve is energized and opened, and the control piston 2, the first regulating valve stem 4 and the valve core 7 move toward the direction of the electrically controlled stop valve 3. The cross-section of the transition portion on the first regulating valve stem 4 and the closing end 107 on the shell 1 increases, and the flow area of ​​the first fuel increases. The first fuel enters the first fuel chamber 101 from the first fuel inlet 302, and the pressure in the first fuel chamber 101 rises until the pressure difference between the second fuel chamber 102 and the first fuel chamber 101 reaches the set value again.

[0087] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A pressure regulating valve for maintaining a pressure deviation between two fuels, characterized in that: include Housing (1); The control piston (2) is capable of sliding along the inner wall of the housing (1), so that a first fuel chamber (101) and a second fuel chamber (102) are formed on both sides of the control piston (2) in the housing (1); An electrically controlled stop valve (3) is arranged at one end of the housing (1) close to the first fuel chamber (101), and the first fuel is introduced into the first fuel chamber (101) by actively opening the electrically controlled stop valve (3); and A multi-stage regulating portion is provided between the electrically controlled stop valve (3) and the control piston (2), and can cooperate with the control piston (2) to perform multiple elastic movements in the first fuel chamber (101) to balance the pressure difference between the first fuel chamber (101) and the second fuel chamber (102); a first fuel conducting portion (301) is provided at the outlet end of the electrically controlled stop valve (3), and the multi-stage regulating portion extends into the first fuel conducting portion (301); Wherein, the multi-stage adjustment part includes a first adjustment part and a second adjustment part; The first regulating part and the second regulating part are elastically connected via a second elastic member (8); the first regulating part is arranged between the first fuel conducting part (301) and the first fuel chamber (101), and is used for variable cross-section conduction of the first fuel from the first fuel conducting part (301) to the first fuel chamber (101) and for preliminary regulation of the pressure difference between the first fuel chamber (101) and the second fuel chamber (102); The second regulating part is arranged in the first fuel chamber (101) to achieve further regulation of the pressure difference between the first fuel chamber (101) and the second fuel chamber (102).

2. The pressure regulating valve for maintaining a pressure difference between two fuels according to claim 1, characterized in that: The first regulating part comprises a first regulating valve stem (4) and a first elastic member (5); The first regulating valve stem (4) is disposed between the first fuel conducting portion (301) and the first fuel chamber (101), and the first regulating valve stem (4) can change the size of the conducting cross section between the first fuel conducting portion (301) and the first fuel chamber (101) by moving; One end of the first elastic member (5) abuts against one end of the first fuel conducting portion (301), and the other end abuts against the first regulating valve stem (4).

3. The pressure regulating valve for maintaining a pressure difference between two fuels according to claim 2, characterized in that: The second regulating part comprises a second regulating valve stem, a second elastic member (8) and a third elastic member (9); One end of the second regulating valve stem is elastically connected to the first regulating valve stem (4) via a second elastic member (8), and the first fuel can pass through the second regulating valve stem and enter a first fuel outlet (103) provided on the housing (1) and communicating with the first fuel chamber (101); The third elastic member (9) abuts between the second regulating valve stem and the control piston (2).

4. The pressure regulating valve for maintaining a pressure difference between two fuels according to claim 3, characterized in that: The second regulating valve stem comprises a limiting sleeve (6) and a valve core (7), the limiting sleeve (6) being fixed in the first fuel chamber (101), and the valve core (7) passing through the limiting sleeve (6); The second elastic member (8) abuts between the valve core (7) and the first regulating valve stem (4).

5. The pressure regulating valve for maintaining a pressure difference between two fuels according to any one of claims 2 to 4, characterized in that: A conical transition portion is provided in the middle of the first regulating valve stem (4), so that a conduction cross section from the first fuel conduction portion (301) to the first fuel chamber (101) has a variable conduction cross section.

6. The pressure regulating valve for maintaining a pressure difference between two fuels according to claim 3, characterized in that: A sealing block (13) is provided at one end of the second regulating valve stem close to the control piston (2).

7. The pressure regulating valve for maintaining a pressure difference between two fuels according to claim 1, characterized in that: The housing (1) is also provided with The first fuel pressure relief port (104) can be connected to the first fuel chamber (101) by controlling the movement of the piston (2); and A second fuel inlet (105) communicates with the second fuel chamber (102); A piston chamber (201) is provided at one end of the control piston (2) close to the first fuel chamber (101).

8. The pressure regulating valve for maintaining a pressure difference between two fuels according to claim 1, characterized in that: A sealing ring (10) is provided on the side of the control piston (2) and abuts against the inner wall of the housing (1); An end cover (11) is provided at one end of the shell (1) located in the second fuel chamber (102).

Images