Claims:CLAIMS

We Claim

1. A high-pressure fuel pump (10), said high-pressure fuel pump (10) comprising:
a housing (12);
a barrel (14) positioned within said housing (12);
a plunger (16) positioned in an element chamber (18) defined within said barrel (14), said plunger (16) adapted to reciprocate within the element chamber (18) to facilitate delivering pressurized fuel from the element chamber (18) to a fuel injector;
a body (20) of a delivery valve positioned above the element chamber (18), the body (20) of the delivery valve comprising a fuel passageway (22) that extends there-through and in flow communication with the element chamber (18) at its first end and in flow communication with a spring chamber (24) at its opposite second end; and
a T-shaped valve (26) inserted within the fuel passageway (22) that extends through the body (20) of the delivery valve from its top portion (50) to facilitate sealing the fuel passageway (22) such that pressurized fuel from the element chamber (18) is prevented from flowing from the element chamber (18) into the spring chamber (24) via the fuel passageway (22).

2. The high-pressure fuel pump (10) in accordance with Claim 1, wherein the T-shaped valve (26) comprises a shank portion (28) and a T-shaped flanged portion (30) that extends from the shank portion (28) at its one end, the shank portion (28) of the T-shaped valve (26) is inserted within the fuel passageway (22) that extends through the body (20) of the delivery valve.

3. The high-pressure fuel pump (10) in accordance with Claim 2, wherein the T-shaped flanged portion (30) comprises a conically shaped bottom edge (32) that extends from the shank portion (28) at its one end, the conically shaped bottom edge (32) that extends from the shank portion (28) at its one end abuts against the top portion (50) of the body (20) of the delivery valve to facilitate sealing the fuel passageway (22) and preventing fuel from flowing from the element chamber (18) into the spring chamber (24) via the fuel passageway (22).

4. The high-pressure fuel pump (10) in accordance with Claim 3, wherein a top of the T-shaped flanged portion (30) comprises a bore (34) that is defined there-through and extends partially through a body of the T-shaped flanged portion (30).

5. The high-pressure fuel pump (10) in accordance with Claim 4, wherein the spring chamber (24) is adapted to receive a spring member (36) therein, wherein a first end (38) of the spring member (36) is inserted within the bore (34) that extends through the body of the T-shaped flanged portion (30), and wherein the opposite second end (40) of the spring member (36) is positioned against an opposite end of the spring chamber (24) such that a tensile force exerted by the first end (38) of the spring member (36) on the top portion of the T-shaped flanged portion (30) that is defined within the bore (34) causes the conically shaped bottom edge (32) that extends from the shank portion (28) at its one end to compress against the top portion (50) of the body (20) of said delivery valve to facilitate sealing the fuel passageway (22) and preventing fuel from flowing from the element chamber (18) into the spring chamber (24) via the fuel passageway (22).

6. The high-pressure fuel pump (10) in accordance with Claim 5, wherein when the pressure of the fuel in the element chamber (18) exceeds the tensile force exerted by the first end of the spring member (36) on the top portion of the T-shaped flanged portion (30) that is defined within the bore (34), the T-shaped valve (26) is lifted upwardly against a resistive force of the spring member (36), thereby opening the fuel passageway (22) and allowing pressurized fuel from flowing from the element chamber (18) into the spring chamber (24) via the fuel passageway (22).
, Description:Complete Specification:

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of the invention
[0001] This invention relates to a T-shaped valve that is positioned at an outlet of a high-pressure fuel pump, and more specifically to a T-shaped valve for a delivery valve body of the high-pressure fuel pump.

Background of the invention
[0002] RU 2052653 C1 describes a double-acting delivery valve for a high-pressure fuel pump of a diesel engine. The delivery valve has composed housing, of which is provided with a seat with conical sealing surface and inlet passageway, and composed straight valving member having flowing passageway. Part 8 of the member is provided with an outer conical sealing surface which is spring member-loaded to a seat by a spring member to permit the conical sealing surfaces to be mated. The flowing passageway of the other part of the valving member is step to define a seat with conical sealing surface mated with the check valving member made up as a ball at the site transient from the narrowed part of the passageway of less diameter to its widened part of greater diameter. The ball is received in the widened part of the flowing passageway with a minimum spaced relation to its walls for permitting movement along the axis of the valve and overlapping step passageway. The ball bears on the supporting member mounted inside the widened part of the passageway with a spaced relation to its surface. The space allows the balls to move in the direction of the longitudinal axis of the valve. The supporting member is spring member-loaded in the direction of the seat by the spring member. Longitudinal grooves are made in the surface of the widened part of the flowing passageway at the same distance from each other over periphery. Face edges of longitudinal grooves are at a distance from the seat defined by the position of the diametrically opposite plane of the ball. There is a space between the ball and the seat when the additional valve is open.

Brief description of the accompanying drawing
[0003] Figure 1 illustrates a high-pressure fuel pump, and more specifically to a T-shaped valve for a delivery valve body of the high-pressure fuel pump.

Detailed description of the embodiments
[0004] A high-pressure fuel pump 10 is described. The high-pressure fuel pump 10 comprises a housing 12, and a barrel 14 positioned within the housing 12. A plunger 16 is positioned in an element chamber 18 defined within the barrel 14. The plunger 16 is adapted to reciprocate within the element chamber 18 to facilitate delivering pressurized fuel from the element chamber 18 to a fuel injector. A body 20 of a delivery valve is positioned above the element chamber 18. The body 20 of the delivery valve comprises a fuel passageway 22 that extends there-through and in flow communication with the element chamber 18 at its first end and in flow communication with a spring chamber 24 at its opposite second end. A T-shaped valve 26 is inserted within the fuel passageway 22 that extends through the body 20 of the delivery valve from its top portion 50 to facilitate sealing the fuel passageway 22 such that pressurized fuel from the element chamber 18 is prevented from flowing from the element chamber 18 into the spring chamber 24 via the fuel passageway 22.

[0005] Figure 1 illustrates a high-pressure fuel pump 10, and more specifically to a T-shaped valve 26 for a body 20 of the delivery valve of the high-pressure fuel pump 10. The high-pressure fuel pump 10 comprises a housing 12. A barrel 14 is positioned within the housing 12 and is thereby secured to the housing 12. In an exemplary embodiment, the barrel 14 comprises an element chamber 18 that is defined within a body of the barrel 14, and is adapted to house a plunger 16 therein. A fuel inlet port 60 is defined along a sidewall of the barrel 14 and is adapted to extend from the element chamber 18 to a fuel gallery 62 that is defined proximate to an outer sidewall of the barrel 14. The plunger 16 is adapted to reciprocate within the element chamber 18 from a bottom dead center position to a top dead center position and vice versa to facilitate delivering pressurized fuel from the element chamber 18 of the high-pressure fuel pump 10 to a fuel injector.

[0006] In an exemplary embodiment, a body 20 of a delivery valve is positioned above the element chamber 18, and is in flow communication with the element chamber 18. More specifically, the body 20 of the delivery valve is positioned above the barrel 14 and comprises a body 20 of the delivery valve and a fuel passageway 22 that extends there-through. The fuel passageway 22 that extends through the body 20 of the delivery valve is in flow communication with the element chamber 18 at its first end. Therefore, pressurized fuel from the element chamber 18 flows into the fuel passageway 22 that extends through the body 20 of the delivery valve and is thereby delivered to a fuel injector. The fuel passageway 22 that extends through the body 20 of the delivery valve is in flow communication with a spring chamber 24 at its opposite second end. In an exemplary embodiment, a T-shaped valve 26 is inserted within the fuel passageway 22 that extends through the body 20 of the delivery valve. More specifically, the T-shaped valve 26 is inserted within the fuel passageway 22 and through the body 20 of the delivery valve from its top end portion such that the T-shaped valve 26 extends through the body 20 of the delivery valve to facilitate sealing the fuel passageway 22. When the T-shaped valve 26 is completely inserted within the fuel passageway 22 that is defined within the body 20 of the delivery valve from its top portion, the fuel passageway 22 is completely sealed by the T-shaped valve 26. Therefore, pressurized fuel from the element chamber 18 is prevented from flowing into the spring chamber 24 via the fuel passageway 22 that is sealed by the T-shaped valve 26.

[0007] In an exemplary embodiment, the T-shaped valve 26 comprises a shank portion 28 that is inserted within the fuel passageway 22 that is defined within the body 20 of the delivery valve from its top portion. A T-shaped flanged portion 30 extends outwardly from the shank portion 28 at its one end. More specifically, the shank portion 28 of the T-shaped valve 26 is inserted within the fuel passageway 22 and extends through the body 20 of the delivery valve, while the T-shaped flanged portion 30 of the T-shaped valve 26 is flush against the outlet of the fuel passageway 22 that is defined in the body 20 of the delivery valve. In an exemplary embodiment, the T-shaped flanged portion 30 of the T-shaped valve 26 comprises a conically shaped bottom edge 32 that extends outwardly from the shank portion 28 at its one end. The conically shaped bottom edge 32 that extends from the shank portion 28 at its one end abuts against the top portion 50 of the body 20 of the delivery valve when fuel is being compressed within the element chamber 18 of the high-pressure fuel pump 10. More specifically, the conically shaped bottom edge 32 that extends from the shank portion 28 at its one end abuts against the top portion 50 of the body 20 of the delivery valve to facilitate sealing the fuel passageway 22. Due to the conically shaped bottom edge 32 abutting against the top portion 50 of the body 20 of the delivery valve, the fuel passageway 22 is completely sealed, thereby preventing fuel from flowing from the element chamber 18 into the spring chamber 24 via the fuel passageway 22 and past the conically shaped bottom edge 32 of the T-shaped flanged portion 30 of the T-shaped valve 26.

[0008] In an exemplary embodiment, a top of the T-shaped flanged portion 30 comprises a bore 34 that is defined there-through. More specifically, the bore 34 that is defined through the top of the T-shaped flanged portion 30 extends partially through a body of the T-shaped flanged portion 30. The bore 34 that is defined through the top of the T-shaped flanged portion 30 is adapted to receive a spring member 36 therein as will be explained in more detail hereinafter.

[0009] In the exemplary embodiment, the spring chamber 24 is adapted to receive a spring member 36 therein. More specifically, a first end of the spring member 36 is inserted within the bore 34 that extends through the body of the T-shaped flanged portion 30. An opposite second end of the spring member 36 is positioned against an opposite end of the spring chamber 24. Therefore, the spring member 36 is positioned between one end of the spring chamber 24 and the bore 34 that extends through the body of the T-shaped flanged portion 30. A tensile force exerted by the first end of the spring member 36 on the top portion of the T-shaped flanged portion 30 that is defined within the bore 34 causes the conically shaped bottom edge 32 of the T-shaped flanged portion 30 to compress against the top portion 50 of the body 20 of the delivery valve. The compression of the conically shaped bottom edge 32 of the T-shaped flanged portion 30 against the top portion 50 of the body 20 of the delivery valve facilitates sealing the fuel passageway 22 that is defined within the body 20 of the delivery valve. Therefore, fuel is prevented from flowing from the element chamber 18 into the spring chamber 24 via the fuel passageway 22 that is defined within the body 20 of the delivery valve.

[0010] In an exemplary embodiment, when the pressure of the fuel in the element chamber 18 exceeds the tensile force exerted by the first end of the spring member 36 on the top portion of the T-shaped flanged portion 30 that is defined within the bore 34, the T-shaped valve 26 is lifted upwardly against a resistive force of the spring member 36. Due to the T-shaped valve 26 being lifted upwardly against the resistive force of the spring member 36, the fuel passageway 22 that is defined within the body 20 of the delivery valve is opened. The opening of the fuel passageway 22 that is defined within the body 20 of the delivery valve facilitates allowing pressurized fuel from flowing from the element chamber 18 into the spring chamber 24 via the fuel passageway 22. The fuel that flows into the spring chamber 24 from the element chamber 18 of the high-pressure fuel pump 10 is channeled from an outlet of the spring chamber 24 to a fuel injector and thereby delivered to the fuel injector.

[0011] A working of the high-pressure fuel pump 10 is described as an example. In its equilibrium position, the conically shaped bottom edge 32 of the T-shaped flanged portion 30 that extends from the shank portion 28 of the T-shaped valve 26 at its one end abuts against the top portion of the body 20 of the delivery valve. The abutment of the T-shaped flanged portion 30 against the top portion of the body 20 of the delivery valve facilitates sealing the fuel passageway 22 and preventing fuel from flowing from the element chamber 18 and into the spring chamber 24 via the fuel passageway 22 that is defined in the body 20 of the delivery valve. When the plunger 16 of the high-pressure fuel pump 10 translates towards its top dead center position within the element chamber 18, the fuel within the element chamber 18 gets pressurized. When the pressure of the fuel within the element chamber 18 exceeds the spring force that is exerted by the spring member 36 on the top portion of the T-shaped flanged portion 30 that extends from the shank portion 28 of the T-shaped valve 26 at its one end, the T-shaped valve 26 is lifted upwardly within the fuel passageway 22 that is defined in the body 20 of the delivery valve. Pressurized fuel flows from the element chamber 18 of the high-pressure fuel pump 10 and into the spring chamber 24 via the fuel passageway 22 that is defined in the body 20 of the delivery valve. The pressurized fuel flows through the spring chamber 24 and is therein delivered to a fuel injector for fuel injection into a cylinder of an engine.

[0012] When the working stroke of the plunger 16 of the high-pressure fuel pump 10 is complete, the pressure of the fuel within the element chamber 18 of the high-pressure fuel pump 10 decreases below the spring force of the spring member 36. The spring member 36 therein exerts a tensile force on the top portion of the T-shaped flanged portion 30 of the T-shaped valve 26. The tensile force exerted on the T-shaped flanged portion 30 of the T-shaped valve 26 by the spring member 36 causes the shank portion 28 of the T-shaped valve 26 to seal the fuel passageway 22 that is defined within the body 20 of the delivery valve. More specifically, the fuel passageway 22 that is defined within the body 20 of the delivery valve is sealed by the abutment of the conically shaped bottom edge- 32 of the T-shaped flanged portion that extends from the shank portion 28 of the T-shaped valve 26 at its one end against the top portion 50 of the body 20 of the delivery valve. The sealing of the fuel passageway 22 by the T-shaped valve 26 facilitates preventing a reverse flow of fuel from the fuel injector back into the element chamber 18 via the fuel passageway 22 that is defined in the body 20 of the delivery valve.

[0013] It must be understood that the embodiments explained above are only illustrative and do not limit the scope of the disclosure. Many modifications in the embodiments regarding dimensions of various components are envisaged and form a part of this invention. The scope of the invention is only limited by the scope of the claims.