Claims:We Claim

1. A high pressure fuel pump (10), said high pressure fuel pump (10) comprising:
a housing (12);
a bore (14) defined within said housing (12) and in flow communication with a pumping chamber of said high pressure fuel pump (10);
a ball valve (16) positioned against a valve seat (18) defined in the bore (14), said ball valve (16) prevents fuel from escaping out of the bore (14) of said high pressure fuel pump (10);
a grub screw (20) positioned against said ball valve (16), said grub screw (20) adapted to compress said ball valve (16) against said valve seat (18) to prevent fuel from escaping out of the bore (14) of said high pressure fuel pump (10); characterized in that
a socket cap (22) positioned against said grub screw (20), said socket cap (22) prevents water from flowing through the gap between said grub screw (20) and said housing (12), and corroding said ball valve (16).

2. The high pressure fuel pump (10) in accordance with Claim 1 wherein said socket cap (22) comprises a shank portion (24) that is inserted between said grub screw (20) and said housing (12), and a flanged portion (26) that is integrally formed with said shank portion (24).

3. The high pressure fuel pump (10) in accordance with Claim 2 wherein said shank portion (24) comprises at least one ridge (28) that is defined on said shank portion (24), said at least one ridge (28) facilitates securing said socket cap (22) between said grub screw (20) and said housing (12).
4. The high pressure fuel pump (10) in accordance with Claim 2 wherein a base of said flanged portion (26) of said socket cap (22) is flush against said pump housing (12) to facilitate sealing said socket cap (22) against said pump 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 high pressure fuel pump, and more specifically to a socket cap for preventing water seepage into the high pressure fuel pump.

Background of the invention
[0002] CN 202188939 U describes a mould water pressure testing device. The utility model provides a mould water pressure testing device which is characterized by comprising a water storage tank, wherein a water pipe is connected with a high pressure pump, the high pressure pump pumps water out of the water storage tank through the water pipe, the high pressure pump is connected with a water outlet pipe which extends into a mould, the water outlet pipe is provided with a pressure indicating gauge and connected with a pressure relief water pipe, the water enters the water storage tank from the water outlet pipe, and the pressure relief water pipe or the water outlet pipe is provided with a pressure relief valve. The mould water pressure testing device has the advantages of being capable of quickly testing whether water seepage exists in multiple sets of moulds simultaneously, so as to save the testing time, being compact and light in weight (the weight can be controlled within 10 kilograms), capable of being erected on a trolley or portable, and being large in water pressure adjusting span, easy to adjust, and capable of running with a common direct-current (DC) power supply.

Brief description of the accompanying drawing
[0003] Figure 1 illustrates a schematic diagram of a high pressure fuel pump illustrating a socket cap for preventing water seepage into the high pressure fuel pump in one embodiment of the invention.
[0004] Figure 2 illustrates the socket cap for preventing water seepage into the high pressure fuel pump in one embodiment of the invention.

Detailed description of the embodiments
[0005] Figure 1 illustrates a schematic diagram of a high pressure fuel pump 10 illustrating the socket cap for preventing water seepage into the high pressure fuel pump 10 in one embodiment of the invention. The high pressure fuel pump 10 comprises a housing 12 and a bore 14 defined within the housing 12 and in flow communication with a pumping chamber of the high pressure fuel pump 10. A ball valve 16 is positioned against a valve seat 18 defined in the bore 14, the ball valve 16 prevents fuel from escaping out of the bore 14 of the high pressure fuel pump 10. A grub screw 20 is positioned against the ball valve 16, the grub screw 20 adapted to compress the ball valve 16 against the valve seat 18 to prevent fuel from escaping out of the bore 14 of the high pressure fuel pump 10. A socket cap 22 is positioned against the grub screw 20, the socket cap 22 prevents water from flowing through the gap between the grub screw 20 and the housing 12, and corroding the ball valve 16.

[0006] In the exemplary embodiment, the high pressure fuel pump 10 comprises a housing 12. A bore 14 is defined within the housing 12 of the high pressure fuel pump 10, and in flow communication with a pumping chamber of the high pressure fuel pump 10. A ball valve 16 is positioned against a valve seat 18 that is defined in the bore 14. More specifically, the ball valve 16 that is positioned against the valve seat 18 that is defined in the bore 14 prevents fuel from escaping from the bore 14, and out of the high pressure fuel pump 10. In the exemplary embodiment, a grub screw 20 is positioned against the ball valve 16. The grub screw 20 is adapted to compress the ball valve 16 against the valve seat 18 to prevent fuel from escaping out of the bore 14 of the high pressure fuel pump 10.

[0007] A socket cap 22 is positioned against the grub screw 20 and secured thereto. In the exemplary embodiment, the socket cap 22 prevents water from flowing through the gap between the grub screw 20 and the housing 12, and corroding the ball valve 16.

[0008] Figure 2 illustrates the socket cap for preventing water seepage into the high pressure fuel pump in one embodiment of the invention. The socket cap 22 comprises a shank portion 24 that is inserted between the grub screw 20 and the housing 12. A flanged portion 26 is integrally formed with the shank portion 24, and extends from the shank portion 24. In an alternate exemplary embodiment, the flanged portion 26 is an independent component and is secured to the shank portion 24 of the socket cap 22 by means of an adhesive. The shank portion 24 comprises at least one ridge 28 that is defined on the shank portion 24. Once the shank portion 24 of the socket cap 22 is inserted between the grub screw 20 and the housing 12, the at least one ridge 28 that is defined on the shank portion 24 of the socket cap 22 facilitates securing the socket cap 22 between the grub screw 20 and the housing 12. Therefore, the at least one ridge 28 that is defined on the shank portion 24 of the socket cap 22 facilitates gripping the shank portion 24 of the socket cap 26 to the housing 12, thereby sealing the space between the grub screw 20 and the housing 12 by means of an interference fit between the socket cap 26 and the housing 12. The base of the flanged portion 26 of the socket cap 22 is flush against the pump housing 12 to facilitate sealing the socket cap 22 against the pump housing 12. Therefore, once water from the external environment falls on the socket cap 22, the water will be unable to flow past the interface of the socket cap 22 and the pump housing 12, and enter through the clearance defined between the grub screw 20 and the housing 12. Therefore, the water will not be permitted to flow and reach the steel ball valve 16, thereby preventing it from getting corroded. Hence the longevity of the steel ball valve 16 is extended and needs to be replaced at a much later point in time, than if it were corroded due to water flowing through the clearance between the grub screw 20 and the housing 12 in the absence of the socket cap 22. In addition, the surface of the socket cap 22 is coated with a hydrophobic material to deflect a flow of water on the socket cap, and preventing water from entering into the space between the socket cap and the housing, and corroding the ball valve 16 over a period of time.

[0009] 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.