Claims:We Claim

1. A fuel injector (10), said fuel injector (10) comprising:
an housing (12) of said fuel injector (10), said housing (12) of said fuel injector (10) comprising at least one vertical groove (14) defined on a wall of said housing (12) of said fuel injector (10);
an injector needle (16) inserted within said housing (12) of said fuel injector (10), said injector needle (16) comprising at least one vertical groove (18) defined on an outer periphery of said injector needle (16), wherein the at least one vertical groove (18) defined on the outer periphery of said injector needle (16) is aligned with the at least one vertical groove (14) defined on the wall of said housing (12) of said fuel injector (10) to facilitate allowing fuel to flow out of said fuel injector (10) via said at least one vertical groove (18) of said injector needle (16).

2. The fuel injector (10) in accordance with Claim 1 wherein the at least one vertical groove (18) defined on the outer periphery of said injector needle (16) comprises a first vertical groove (20) that extends from a neck portion of said injector needle (16) partially along a length of said injector needle (16), and a second vertical groove (22) that is spaced apart from the first vertical groove (20) and extends along the length of said injector needle towards a base portion of said injector needle (16).

3. The fuel injector (10) in accordance with Claim 2 further comprising at least one horizontal groove (18) defined about a circumference of said injector needle (16) and defined between the first vertical groove (20) and the second vertical groove (22), said at least one horizontal groove (18) adapted to retain fuel that flows through a clearance that is defined between said injector needle (16) and said housing (12) of said fuel injector (10).

4. The fuel injector (10) in accordance with Claim 2 further comprising an actuator (24) inserted within said injector needle (16), said actuator (24) adapted to rotate said injector needle (16) to facilitate aligning the first vertical groove (20) of said injector needle (16) with the at least one vertical groove (14) that is defined on the wall of said housing (12) of said fuel injector (10) to deliver pressurized fuel from the fuel injector (10) when the fuel injector (10) is in operation, said actuator (24) further adapted to rotate said injector needle (16) to facilitate misaligning the first vertical groove (20) of said injector needle (16) with the at least one vertical groove (14) that is defined on the wall of said injector housing (12) to cut off a supply of pressurized fuel from the fuel injector (10) when the fuel injector (10) is deactivated.

5. The fuel injector (10) in accordance with Claim 4 wherein said actuator (24) may be one of an electromagnetic actuator, a mechanical actuator, and an electrical actuator.

6. The fuel injector (10) in accordance with Claim 1 wherein a width and a depth of said at least one vertical groove (14) is user defined.

7. The fuel injector (10) in accordance with Claim 1 wherein a number of said at least one vertical groove (14) that are defined around a periphery of said injector needle (16) is equal to a number of spray holes that are defined around a periphery of said injector housing (12).
, 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 fuel injector, and more specifically to a fuel injector comprising a rotating needle that is integrated therein.

Background of the invention
[0002] US 2002092929 A describes a fuel injection nozzle that is provided for a diesel engine. The fuel injection nozzle includes a nozzle body having a tip end portion, a top end portion having an opening edge, and a fuel inlet passage, a needle valve inserted in the nozzle body, and a bag-shaped rotary valve fitted with the tip end portion of the needle valve. The nozzle body has a first protrusion protruding from an inner peripheral surface toward a center axis of the nozzle body. The needle valve has a first guide groove being engaged with the first protrusion and a second guide groove. The rotary valve has a second protrusion protruding toward the center axis and being engaged with the second guide groove. This fuel injection nozzle may realize good combustion performance and good exhaust emission performance. Also the fuel injection nozzle may have a simple structure without increasing the size of the injector assembly.

Brief description of the accompanying drawing
[0003] Figure 1 illustrates a fuel injector that comprises a rotating needle that is integrated within the fuel injector.
[0004] Figure 2 illustrates a profile view of the fuel injector depicting the first vertical groove and the second vertical groove.

Detailed description of the embodiments
[0005] Figure 1 illustrates a fuel injector 10 that comprises a rotating needle 16 that is integrated within the fuel injector 10. The fuel injector 10 comprises a housing 12 of a fuel injector 10, the housing 12 of the fuel injector 10 comprising at least one vertical groove 14 defined on a wall of the housing 12 of the fuel injector 10. An injector needle 16 is inserted within the housing 12 of the fuel injector 10, the injector needle 16 comprising at least one vertical groove 18 defined on an outer periphery of the injector needle 16. The at least one vertical groove 18 defined on the outer periphery of the injector needle 16 is aligned with the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10 to facilitate allowing fuel to flow out of the fuel injector 10 via the at least one vertical groove 18 of the injector needle 16.

[0006] The fuel injector 10 comprises an injector housing 12. The housing 12 of the fuel injector 10 has a vertical groove 14 that is circumferentially defined around the internal wall of the housing 12 of the fuel injector 10. The vertical groove 14 that is circumferentially defined around the internal wall of the housing 12 of the fuel injector 10 is in flow communication with the spray holes of the fuel injector 10 and is adapted to channel fuel that flows into the fuel injector 10 through the spray holes of the fuel injector 10 into an engine. In the exemplary embodiment, the groove that is circumferentially defined around the internal wall of the housing 12 of the fuel injector 10 extends vertically from a first portion 11 of the housing 12 of the fuel injector 10 to a second portion 13 of the housing 12 of the fuel injector 10 and is adapted to channel fuel from the first portion 11 of the injector housing 12 to the second portion 13 of the housing 12 of the fuel injector 10 as fuel is continuously supplied to the fuel injector 10.

[0007] ] Figure 2 illustrates a profile view of the fuel injector depicting the first vertical groove and the second vertical groove. In the exemplary embodiment, an injector needle 16 is integrated within the fuel injector 10. More specifically, the injector needle 16 is inserted within the housing 12 of the fuel injector 10 and is adapted to regulate a flow of fuel from the fuel injector 10 to an engine. The injector needle 16 comprises at least one vertical groove 20 that is defined on an outer periphery of the injector needle 16. The at least one vertical groove 20 that is defined on the outer periphery of the injector needle 16 extends vertically from a neck portion of the fuel injector 10 partially along a length of the fuel injector 10. The at least one vertical groove 20 that is defined on the outer periphery of the injector needle 16 is aligned with the at least one vertical groove 14 that is defined on the wall of the injector housing 12. The alignment of the at least one vertical groove 20 that is defined on the outer periphery of the injector needle 16 with the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10 facilitates allowing fuel to flow out of the fuel injector 10 via the at least one vertical groove 18 of the injector needle 16.

[0008] In an exemplary embodiment, a second vertical groove 22 is spaced apart from the first vertical groove 18 and extends along the length of the injector needle 16 towards a base portion of the injector needle 16. The second vertical groove 22 is defined on the outer periphery of the injector needle 16. The second vertical groove 22 that is defined on the outer periphery of the injector needle 16 extends vertically from the spaced apart portion of the first vertical groove 20 and extends partially along a length of the fuel injector 10. A top portion of the second vertical groove 22 is aligned with the at least one vertical groove 14 that is defined on the wall of the injector housing 12. Therefore, the fuel that flows through the at least one vertical groove 14 that is defined on the wall of the injector housing 12 from the first vertical groove 20 of the injector needle 16 is channeled through the second vertical groove 22 towards the base portion of the injector needle 16.

[0009] The second vertical groove 22 that is defined on the injector needle 16 is in flow communication with the spray holes of the fuel injector 10. Therefore, the fuel that is channeled through the second vertical groove 22 from the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10 is channeled to the spray holes of the fuel injector 10 that is defined on the housing 12 of the fuel injector 10 and injected into the engine cylinder. More specifically, a bottom portion of the second vertical groove 22 that is proximate with the base portion of the injector needle 16 is aligned with the spray holes of the fuel injector 10 and is adapted to deliver pressurized fuel through the spray holes of the fuel injector 10.

[0010] In an exemplary embodiment, at least one horizontal groove 18 is defined about a circumference of the injector needle 16. The at least one horizontal groove 18 is defined between the first vertical groove 20 and the second vertical groove 22. More specifically, the at least one horizontal groove 18 that is defined between the first vertical groove 20 and the second vertical groove 22 may comprise two or more horizontal grooves 18 that are spaced apart from one another to constitute a series of vertically spaced horizontal grooves 18 that are each defined about the outer periphery of the injector needle 16. Each of the horizontal grooves 18 that are defined between the first vertical groove 20 and the second vertical groove 22 are adapted to retain fuel. More specifically, the fuel that flows through the clearance that is defined between the injector needle 16 and the housing 12 of the fuel injector 10 is arrested and retained within each of the horizontal grooves 18. Therefore, when the fuel injector 10 is not in operation and fuel is not required to be injected from the fuel injector 10, the pressurized fuel that flows through the clearance that is defined between the injector needle 16 and the housing 12 of the fuel injector 10 is retained within each of the horizontal grooves 18 and is not channeled out of the fuel injector 10 via the spray holes that are defined on the injector housing 12. Once the fuel injector 10 is in operation and is required to inject fuel as will be explained in detail below, the fuel that is retained within each of the horizontal grooves 18 are channeled out of the fuel injector 10 via the second vertical groove 22 and delivered to the engine.

[0011] In an exemplary embodiment, the fuel injector 10 further comprises an actuator 24 that is inserted within a portion of the injector needle 16 and electrically actuated by means of an engine control unit. More specifically, the actuator 24 that is inserted within the portion of the injector needle 16 is adapted to rotate the injector needle 16 to facilitate aligning the first vertical groove 20 of the injector needle 16 with the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10. Therefore, the engine control unit is adapted to rotate the injector needle 16 to facilitate aligning the first vertical groove 20 of the injector needle 16 with the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10.

[0012] When the injector needle 16 is rotated to align the first vertical groove 20 of the injector needle 16 with the at least one vertical groove 14 that is defined on the wall of the injector housing 12, the pressurized fuel that flows through the first vertical groove 20 of the injector needle 16 is channeled into the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10. Therefore, the pressurized fuel that is channeled through the vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10 is delivered out of the fuel injector 10 to an engine cylinder when the fuel injector 10 is in operation. More specifically, the fuel that is channeled through the vertical groove 14 that is defined on the wall of the injector housing 12 is channeled through the second vertical groove 22 that is defined in the injector needle before being delivered out of the fuel injector 10 via the plurality of spray holes that are defined on the wall of the injector housing 12 and in flow communication with the second vertical groove 22 that is defined in the injector needle 16.

[0013] When fuel injection is complete and the fuel injector 10 is not required to be operated, the actuator 24 is adapted to rotate the injector needle 16 to facilitate misaligning the first vertical groove 20 of the injector needle 16 with the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10 to cut off a supply of pressurized fuel from the fuel injector 10 when the fuel injector 10 is deactivated. More specifically, when the fuel injector 10 is required to be deactivated, the engine control unit transmits a signal to the actuator 24 thereby inducing the actuator 24 to rotate the injector needle 16. The rotation of the injector needle 16 facilitates misaligning the first vertical groove 20 of the injector needle 16 with the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10 to cut off a supply of pressurized fuel from the fuel injector 10 to the engine.

[0014] In an exemplary embodiment, the actuator 24 may be one of an electromagnetic actuator, a mechanical actuator, and an electrical actuator. In an alternate exemplary embodiment, the actuator 24 may be any type of actuator that is known in the art that facilitates rotating the injector needle 16 to deliver pressurized fuel from the first vertical groove 20 that is defined in the injector needle 16 and out of the fuel injector 10 to the engine cylinder via the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10 and the second vertical groove 22 that is defined in the injector needle 16. Moreover, in the exemplary embodiment, a width and a depth of the first vertical groove 20 that is defined in the injector needle 16, a width and a depth of the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10, and a width and a depth of the second vertical groove 22 that is defined in the injector needle 16 is user defined and may be varied by a user depending on the application.

[0015] In an exemplary embodiment, a number of the second vertical grooves 22 that are defined around a periphery of the injector needle 16 is equal to a number of spray holes that are defined around a periphery of the housing 12 of the fuel injector 10. Therefore, the fuel that is channeled through each of the second vertical grooves 22 that are defined around the periphery of the injector needle 16 is injected through each of the spray holes that are defined around the periphery of the housing 12 if the fuel injector 10. With an increase in the number of spray holes that are defined around the periphery of the housing 12 of the fuel injector 10, the number of second vertical grooves 22 that are defined around the periphery of the housing 12 of the fuel injector 10 correspondingly increases to be equal to the number of spray holes that are defined around the periphery of the housing 12 of the fuel injector 10.

[0016] A working of the fuel injector 10 comprising the rotating needle 16 is described as an example. When the actuator 10 that is secured to the injector needle 16 is adapted to rotate the injector needle 16, the first vertical groove 20 of the injector needle 16 is aligned with the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10. Therein the fuel that flows through the fuel injector 10 is allowed to flow through the first vertical groove 20 of the injector needle 16. Therein, the fuel that flows through the first vertical groove 20 of the injector needle 16 is allowed to flow through the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10 is channeled through the second vertical groove 22 of the injector needle 16. The fuel that flows through the second vertical groove 22 of the injector needle 16 ultimately flows out of the fuel injector 10 via the plurality of spray holes that are defined on the wall of the housing 12 of the fuel injector 10. When fuel injection is complete, the actuator 10 rotates the injector needle 16 such that the first vertical groove 20 of the injector needle 16 is misaligned with the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10.

[0017] Therefore, due to the misalignment of the first vertical groove 20 of the injector needle 16 with the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10, the fuel that is channeled through the first vertical groove 20 of the injector needle 16 is not allowed to flow through the at least one vertical groove 14 that is defined on the wall of the housing 12 of the fuel injector 10, and is therefore retained within the first vertical groove 20 of the injector needle 16. As a consequence, fuel is not injected from the fuel injector 10 into the engine. However, the pressurized fuel that is channeled within the fuel injector 10 is channeled through the clearance between the first vertical groove 20 and the wall of the housing 12 of the fuel injector 10. The fuel that is channeled through the clearance between the first vertical groove 20 and the wall of the housing 12 of the fuel injector 10 is retained within each of the horizontal grooves 18 that are defined between the first vertical groove 20 and the second vertical groove 22. More specifically, the fuel that flows through the clearance that is defined between the injector needle 16 and the housing 12 of the fuel injector 10 is arrested and retained within each of the horizontal grooves 18.

[0018] Therefore, when the fuel injector 10 is not in operation and fuel is not required to be injected from the fuel injector 10, the pressurized fuel that flows through the clearance that is defined between the injector needle 16 and the housing 12 of the fuel injector 10 is retained within each of the horizontal grooves 18. The pressurized fuel is therefore not channeled out of the fuel injector 10 via the spray holes that are defined on the housing 12 of the fuel injector 10. Once the fuel injector 10 is in operation and is required to inject fuel, the fuel that is retained within each of the horizontal grooves 18 are channeled out of the fuel injector 10 via the second vertical groove 22 and delivered to the engine.

[0019] 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 with regard to 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.