CN218440838U

CN218440838U - Overflow valve is opened to second grade

Info

Publication number: CN218440838U
Application number: CN202222402717.1U
Authority: CN
Inventors: 奚阳; 于建锋; 解芳; 潘慧; 于春朝; 高展
Original assignee: Junfeng Electronic Control Technology Dalian Co ltd
Current assignee: Junfeng Electronic Control Technology Dalian Co ltd
Priority date: 2022-09-09
Filing date: 2022-09-09
Publication date: 2023-02-03
Anticipated expiration: 2032-09-09

Abstract

The invention relates to the technical field of fuel feed pumps of fuel injection systems for diesel engines, and discloses an overflow valve with a two-stage opening function. The spring and the valve core are pressed in the valve body by the sealing steel ball, the conical surface of the valve core is abutted against the conical surface of the valve body, so that the inner cavity of the valve core is sealed, when the oil pressure in the oil duct reaches a certain degree, the overflow valve is opened in two stages one by one, the oil pressure in the oil pump is stable, the problem that the overflow valve cannot be opened when an oil return port is blocked is avoided, and the overall safety of the oil pump is ensured.

Description

Overflow valve is opened to second grade

Technical Field

The application relates to the technical field of fuel feed pumps of fuel injection systems for diesel engines, in particular to a secondary opening overflow valve.

Background

In diesel engine fuel injection system's oil feeding system, need provide stable high-pressure fuel through the fuel feed pump, must have stable low pressure fuel supply at low pressure oil feed end, also need maintain the oil pressure stable in the whole return circuit to guarantee in heavy, extra-heavy engine, the fuel feed pump can stably provide great fuel delivery, and the problem of existence is: in the prior art, an overflow valve adopted by the oil supply pump is a single-stage opening overflow valve, when a valve core opens for oil drainage, the valve core needs to move a large distance to obtain a large oil drainage amount, so that the oil pressure is easy to be unstable, and when an oil return port is closed, the overflow valve cannot be opened due to pressure balance at two ends of the valve core, so that the oil pressure is kept stable.

Disclosure of Invention

To the problem that prior art exists, the purpose of this application embodiment is to provide a overflow valve is opened to second grade.

According to the first aspect of the embodiment of the application, the two-stage opening overflow valve is applied to the fuel supply pump of the fuel injection system for the diesel engine and comprises a valve body, a valve core, a spring and a sealing steel ball;

the valve body is internally provided with an axial through hole, the axial through hole forms a sealing section, a spring cavity and an oil inlet section with the diameters being reduced in sequence from left to right, the tail end of the oil inlet section is provided with one valve body primary oil passage hole, the primary oil passage hole is connected with an oil pump cavity through an oil duct when being opened, the oil inlet section is close to the position of the spring cavity, a plurality of valve body secondary oil passage holes are arranged and uniformly distributed along the radial direction, the secondary oil passage hole is connected with an oil inlet end of an oil supply pump through the oil duct when being opened, and a valve body conical surface is arranged at the joint of the spring cavity and the oil inlet section and used for carrying out conical surface sealing with the valve core;

the valve core is of a thin cylindrical structure, a valve core conical surface matched with the valve body conical surface is arranged on the inner side of the large end of the valve core, the outer diameter of the small end of the valve core is matched with the oil inlet section forming hole shaft, the inner cavity of the valve core is communicated with the small end, a spring seat is arranged on the outer side of the large end of the valve core, a plurality of valve core oil passage holes which are uniformly distributed along the diameter direction are formed in the middle of the valve core, and the valve core oil passage holes are communicated with the valve body secondary oil passage holes when the secondary valve is opened;

the sealing steel ball is arranged in the sealing section and is in interference fit with the inner wall of the sealing section; one end of the spring is sleeved on the spring seat, and the other end of the spring is in contact with the sealing steel ball.

Further, the outer diameter of the spring cavity is provided with mounting threads.

Further, a tightening plane is arranged on the outer diameter of the sealing section.

The technical scheme provided by the embodiment of the application can have the following beneficial effects:

according to the embodiment, the overflow valve can still work when the oil return port is blocked, and the oil pressure is kept stable; part of the fuel is directly discharged back to the oil inlet end of the fuel feed pump, so that the oil quantity is supplemented, and the problem of oil pressure protrusion at the oil inlet end is solved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and together with the description, serve to explain the principles of the application.

FIG. 1 is an exploded view of a two-stage open spill valve according to an exemplary embodiment.

FIG. 2 is a schematic diagram illustrating an unopened state of a two-stage open excess flow valve in accordance with an exemplary embodiment.

FIG. 3 is a schematic diagram illustrating a one-stage opening state of a two-stage opening excess flow valve according to an exemplary embodiment.

FIG. 4 is a schematic diagram illustrating a two-stage open state of a two-stage open spill valve, according to an exemplary embodiment.

Reference numerals are as follows:

1. a valve body; 2. a valve core; 3. sealing the steel ball; 4. a spring; 5. a first-stage oil passage hole of the valve body; 6. a valve core oil passage hole; 7. a secondary oil passage hole of the valve body; 8. the inner cavity of the valve core; 9. a valve body conical surface; 10. a conical surface of the valve core; 11. tightening the plane; 12. a spring seat.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings in which the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present application. The word "if" as used herein may be interpreted as "at" \8230; "or" when 8230; \8230; "or" in response to a determination ", depending on the context.

Fig. 1 is an exploded view showing a two-stage opening relief valve according to an exemplary embodiment, as shown in fig. 1, which is applied to a fuel supply pump of a fuel injection system for a diesel engine and may include a valve body 1, a valve element 2, a spring 4, and a sealing steel ball 3; the valve body 1 is internally provided with an axial through hole, the axial through hole forms a sealing section, a spring cavity and an oil inlet section with the diameters sequentially reduced from left to right, the tail end of the oil inlet section is provided with one valve body primary oil passage hole 5, the primary oil passage hole is connected with an oil pump cavity through an oil passage when the primary oil passage is opened, the oil inlet section is close to the position of the spring cavity, a plurality of valve body secondary oil passage holes 7 are arranged and uniformly distributed along the radial direction, the secondary oil passage hole is connected with the oil inlet end of an oil supply pump when the secondary oil passage is opened, and the joint of the spring cavity and the oil inlet section is provided with a valve body conical surface 9 for carrying out conical surface sealing with the valve core 2; the valve core 2 is of a thin cylindrical structure, a valve core conical surface 10 matched with the valve body conical surface 9 is arranged on the inner side of the large end of the valve core 2, the outer diameter of the small end of the valve core is matched with the oil inlet section forming hole shaft, the inner cavity of the valve core 2 is communicated with the small end, a spring seat 12 is arranged on the outer side of the large end of the valve core 2, a plurality of valve core oil passage holes 6 uniformly distributed along the diameter direction are formed in the middle of the valve core 2, and the valve core oil passage holes are communicated with the valve body secondary oil passage holes 7 when the valve core is opened for the second time; the sealing steel ball 3 is arranged in the sealing section and is in interference fit with the inner wall of the sealing section; one end of the spring 4 is sleeved on the spring seat 12, and the other end of the spring 4 is in contact with the sealing steel ball 3.

Specifically, the outer diameter of the spring cavity is provided with mounting threads for mounting a secondary opening overflow valve; and a screwing plane 11 is arranged on the outer diameter of the sealing section, so that a tool can be conveniently screwed.

In one embodiment, the secondary opening overflow valve comprises a valve body 1, a valve core 2, a spring 4 and a sealing steel ball 3; an axial through hole is formed in the valve body 1, and a sealing section, a spring cavity and an oil inlet section are sequentially formed in the axial through hole from left to right; the diameter of the oil inlet section is smaller than that of the spring cavity, the diameter of the spring cavity is smaller than that of the sealing section, and the oil inlet section and the spring cavity are transited through the conical surface of the valve body; mounting threads are arranged at the outer diameter position of a spring cavity of the valve body 1 and used for mounting overflow valve parts; a screwing plane 11 is arranged at the outer diameter position of the sealing section of the valve body 1, so that a tool can be conveniently used for screwing; the tail end of the oil inlet section of the valve body 1 is provided with one first-stage oil passage hole of the valve body, and the first-stage oil passage hole is connected with the pump cavity of the oil supply pump through an oil passage when being opened at the first stage; the oil inlet section of the valve body 1 is close to the spring cavity, four secondary oil passage holes of the valve body are arranged and uniformly distributed along the radial direction, and the secondary oil passage holes are connected with the oil inlet end of the oil supply pump through an oil passage when the secondary oil passage is opened; the valve core 2 is of a thin cylindrical structure, the outer side of the large end is provided with a boss spring seat 12 structure, the inner side of the large end is provided with a valve core conical surface, and the slope conforms to the valve body conical surface; the inner cavity is communicated with the small end and is not communicated with the big end of the valve core 2; two valve core oil passage holes 6 are uniformly distributed in the middle of the valve core 2 along the diameter direction, and are connected with a valve body secondary oil passage hole 7 when the secondary valve is opened and are connected with the oil inlet end of an oil transfer pump.

As shown in fig. 2, the sealing steel ball 3 is arranged in the sealing section of the valve body 1, and the sealing steel ball 3 is in interference fit with the inner wall of the sealing section; the outer diameter of the small end of the valve element 2 is matched with the oil inlet section of the valve body 1 in a hole-shaft mode, the right end of the spring 4 is sleeved on the spring seat 12 at the large end of the valve element 2, the left end of the spring 4 is in contact with the sealing steel ball 3, the reset spring 4 can tightly support the upper conical surface of the large end of the valve element 2 on the conical surface 9 of the valve body, the first-stage oil passage hole 5 of the valve body, the valve element oil passage hole 6 and the second-stage oil passage hole 7 of the valve body are all blocked and closed by the outer wall of the valve element 2 at the moment, and an oil drainage oil path is blocked at the moment.

The application provides a theory of operation that overflow valve was opened to second grade is: fuel enters a valve core inner cavity 8 from the valve core 2, when the oil pressure reaches a first-stage opening pressure, the fuel pushes the valve core 2 to move along an oil inlet section of the valve body 1, the spring 4 is compressed, and a valve body conical surface 9 is separated from a valve core conical surface 10; when the valve core 2 runs to enable the primary oil channel hole 5 of the valve body to be communicated, part of fuel oil enters an oil channel along the primary oil channel hole 5 of the valve body, and the fuel oil returns to an oil tank, as shown in fig. 3; when the oil pressure reaches the secondary opening pressure, the valve core 2 continues to move, when the secondary oil passage hole of the valve core 2 is communicated with the secondary oil passage hole 7 of the valve body, part of the fuel oil returns to the oil inlet end of the oil supply pump along the oil passage to maintain the oil supply quantity and the oil pressure of the oil supply end, and when the valve core oil passage 6 is completely communicated with the secondary oil passage hole 7 of the valve body, the overflow quantity reaches the maximum value, so that the function of maintaining the oil pressure in the oil supply pump is achieved, as shown in fig. 4; when an oil return port of the oil supply pump is blocked, the primary oil passage hole 5 of the valve body cannot discharge oil, the oil pressure is continuously increased, the valve core 2 continuously moves, and when the secondary opening pressure is reached, the valve core penetrates through the secondary oil passage hole 7 of the valve body to discharge fuel oil back to the oil inlet end of the oil supply pump, so that the stability of the oil pressure is ensured.

Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains.

It will be understood that the present application is not limited to the precise arrangements that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof.

Claims

1. A two-stage opening overflow valve is characterized in that the overflow valve is applied to an oil supply pump of a fuel injection system for a diesel engine and comprises a valve body (1), a valve core (2), a spring (4) and a sealing steel ball (3);

the valve body (1) is internally provided with an axial through hole, the axial through hole forms a sealing section, a spring cavity and an oil inlet section with the diameters sequentially reduced from left to right, the tail end of the oil inlet section is provided with one valve body primary oil passage hole (5), the primary oil passage hole is connected with an oil pump cavity through an oil passage when being opened, the oil inlet section is close to the position of the spring cavity, a plurality of valve body secondary oil passage holes (7) are arranged and uniformly distributed along the radial direction, the secondary oil passage hole is connected with the oil inlet end of an oil supply pump during being opened, and a valve body conical surface (9) is arranged at the joint of the spring cavity and the oil inlet section and is used for carrying out conical surface sealing with the valve core (2);

the valve core (2) is of a thin cylindrical structure, a valve core conical surface (10) matched with the valve body conical surface (9) is arranged on the inner side of the large end of the valve core (2), the outer diameter of the small end is matched with the oil inlet section forming hole shaft, the inner cavity of the valve core (2) is communicated with the small end, a spring seat (12) is arranged on the outer side of the large end of the valve core (2), a plurality of valve core oil channel holes (6) uniformly distributed along the diameter direction are formed in the middle of the valve core (2), and the valve core oil channel holes are communicated with the valve body secondary oil channel holes (7) when the secondary valve is opened;

the sealing steel ball (3) is arranged in the sealing section and is in interference fit with the inner wall of the sealing section; one end of the spring (4) is sleeved on the spring seat (12), and the other end of the spring (4) is in contact with the sealing steel ball (3).

2. The two-stage opening overflow valve of claim 1, wherein the spring cavity is provided with mounting threads on an outer diameter.

3. The two-stage opening overflow valve of claim 1, wherein the sealing section is provided with a tightening plane (11) on its outer diameter.