Abstract: A fluid pump has a cylinder supporting a plunger and a pump housing formed with dissimilar metals. A pressing mechanism presses the cylinder and the pump housing relative to each other so that a pressurizing chamber is sealed through a pressing surface between the pump housing and the cylinder. The number of seal points can be reduce, and a reduction in reliability can be eliminated while realizing a reduction in weight of the pump housing and a reduction in cost due to increase in cutting capability, by using a soft material such as an aluminum alloy for the pump housing.

Abstract: A high pressure fuel pump for an internal combustion engine having a cylinder, a plunger slidably fitted in the cylinder and a seal mechanism for blocking fuel leakage from an end of a sliding portion between the cylinder and the plunger and also for preventing an lubricant for a driving mechanism of the plunger from entering into the cylinder from the end of the sliding portion of the cylinder and the plunger. A holder surrounding the end of the sliding portion of the cylinder and the plunger is provided. The seal mechanism comprises two mutually independent seal devices mounted with a specific spacing in a longitudinal direction from the end of the sliding portion of the cylinder and the plunger along a circumference of the plunger. The two seal devices are held on the circumference of the plunger by the holder surrounding the end of the sliding portion of the cylinder and the plunger while keeping the specific spacing.

Abstract: A simple structured high-pressure fuel pump. A fuel pump comprises a reciprocably-supported cylinder, a pressurizing chamber using part of the outer surface of the cylinder as the wall surface which move to change the internal volume, a fuel intake passage forming a fuel passage which introduces fuel to the pressurizing chamber, a fuel discharge passage for the compressed fuel coming out from the pressurizing chamber. A fuel intake valve is provided in fuel intake passage. A fuel discharge valve is provided in said fuel discharge passage. A connecting passage connects upstream side of the intake valve in the fuel intake passage and the downstream side of it. A check valve which flows fuel from the fuel discharge flow passage to the fuel intake passage is provided in the connecting passage.

Abstract: A high pressure fuel pump for an internal combustion engine having a cylinder, a plunger slidably fitted in the cylinder and a seal mechanism for blocking fuel leakage from an end of a sliding portion between the cylinder and the plunger and also for preventing an lubricant for a driving mechanism of the plunger from entering into the cylinder from the end of the sliding portion of the cylinder and the plunger. A holder surrounding the end of the sliding portion of the cylinder and the plunger is provided. The seal mechanism comprises two mutually independent seal devices mounted with a specific spacing in a longitudinal direction from the end of the sliding portion of the cylinder and the plunger along a circumference of the plunger. The two seal devices are held on the circumference of the plunger by the holder surrounding the end of the sliding portion of the cylinder and the plunger while keeping the specific spacing.

Abstract: Disclosed herein is a fuel pump for an inter-cylinder direct fuel injection apparatus, in which occurrence of corrosion and attrition caused by cavitation or erosion can be suppressed, their resistance against the environment can be improved, and an excellent lifetime can be achieved in the case of the use of an aluminum material even if the temperature reaches as high as 100° C. or higher and the pressure reaches as high as 7 to 12 MPa. In the fuel pump for an inter-cylinder direct fuel injection apparatus, made of aluminum or an aluminum alloy, a coating film plated with Ni—P or a Ni—P based material is formed by electroless plating.

Abstract: Disclosed herein is a fuel pump for an inter-cylinder direct fuel injection apparatus, in which occurrence of corrosion and attrition caused by cavitation or erosion can be suppressed, their resistance against the environment can be improved, and an excellent lifetime can be achieved in the case of the use of an aluminum material even if the temperature reaches as high as 100° C. or higher and the pressure reaches as high as 7 to 12 MPa. In the fuel pump for an inter-cylinder direct fuel injection apparatus, made of aluminum or an aluminum alloy, a coating film plated with Ni—P or a Ni—P based material is formed by electroless plating.

Abstract: A fuel pump, of which sliding mechanism parts in its fuel chamber have good wear resistance under a severe environment, and a direct fuel injection engine using the fuel pump are provided. In a fuel pump for pressurizing and delivering fuel to a fuel injector of a vehicle engine, at least one of sliding surfaces of a slant plate, a slipper and a plunger sliding in a lubricating oil and at least one of sliding surfaces of sliding members of a plunger and a cylinder contacting with and sliding on each other through the fuel are formed of a hardened layer composed of any one of a nitrided layer, a carburization quenched layer and a carbonitrided layer, or coated with a high corrosion resistant and hard metal compound layer over the hardened layer.

Abstract: A seal mechanism with improved pressure tightness is provided to eliminate a return piping to a fuel tank used for reducing pressure applied to the seal mechanism in a high pressure fuel pump. The seal mechanism includes a stress reduction mechanism for reducing the stress generated at the junction between its retaining member and flexible member.

Abstract: A high pressure fuel pump for an internal combustion engine having a cylinder, a plunger slidably fitted in the cylinder and a seal mechanism for blocking fuel leakage from an end of a sliding portion between the cylinder and the plunger and also for preventing an lubricant for a driving mechanism of the plunger from entering into the cylinder from the end of the sliding portion of the cylinder and the plunger. A holder surrounding the end of the sliding portion of the cylinder and the plunger is provided. The seal mechanism comprises two mutually independent seal devices mounted with a specific spacing in a longitudinal direction from the end of the sliding portion of the cylinder and the plunger along a circumference of the plunger. The two seal devices are held on the circumference of the plunger by the holder surrounding the end of the sliding portion of the cylinder and the plunger while keeping the specific spacing.

Abstract: A fluid pump, wherein a cylinder supporting a plunger and a pump housing are formed with dissimilar metals and a pressing mechanism to press the cylinder and the pump housing relatively to each other is provided so that a pressurizing chamber is sealed through a pressing surface between the pump housing and the cylinder, whereby the number of seal points can be reduced and a reduction in reliability can be eliminated while realizing a reduction in weight of the pump housing and a reduction in cost due to increase in cutting capability using a soft member such as aluminum alloy for the pump housing.

Abstract: Disclosed herein is a fuel pump for an inter-cylinder direct fuel injection apparatus, in which occurrence of corrosion and attrition caused by cavitation or erosion can be suppressed, their resistance against the environment can be improved, and an excellent lifetime can be achieved in the case of the use of an aluminum material even if the temperature reaches as high as 100° C. or higher and the pressure reaches as high as 7 to 12 MPa. In the fuel pump for an inter-cylinder direct fuel injection apparatus, made of aluminum or an aluminum alloy, a coating film plated with Ni—P or a Ni—P based material is formed by electroless plating.

Abstract: A simple structured high-pressure fuel pump.

Abstract: A fuel pump, of which sliding mechanism parts in its fuel chamber have good wear resistance under a severe environment, and a direct fuel injection engine using the fuel pump are provided.

Abstract: In a fuel pump pressurizing fuel and supplying the fuel to a fuel injection valve of a vehicle engine, a hardened layer of at least one selected from a nitride layer, a carburated and quenched layer and a carbonitrided layer, and a metal compound layer, on a surface of the hardened layer, higher in corrosion resistance than the hardened layer are formed on one of slide surfaces contacting each other and sliding in fuel.

Abstract: A high pressure fuel pump for an internal combustion engine having a cylinder, a plunger slidably fitted in the cylinder and a seal mechanism for blocking fuel leakage from an end of a sliding portion between the cylinder and the plunger and also for preventing an lubricant for a driving mechanism of the plunger from entering into the cylinder from the end of the sliding portion of the cylinder and the plunger. A holder surrounding the end of the sliding portion of the cylinder and the plunger is provided. The seal mechanism comprises two mutually independent seal devices mounted with a specific spacing in a longitudinal direction from the end of the sliding portion of the cylinder and the plunger along a circumference of the plunger. The two seal devices are held on the circumference of the plunger by the holder surrounding the end of the sliding portion of the cylinder and the plunger while keeping the specific spacing.

Abstract: A seal mechanism with improved pressure tightness is provided to eliminate a return piping to a fuel tank used for reducing pressure applied to the seal mechanism in a high pressure fuel pump. The seal mechanism includes a stress reduction mechanism for reducing the stress generated at the junction between its retaining member and flexible member.

Abstract: An axial plunger pump which does not need bellows by restricting fuel to a cylinder bore configuring a pump portion and by lubricating the other portion with oil. The high pressure fuel pump includes a plunger reciprocating according to a shaking movement of a swash plate, a cylinder block forming a pump chamber together with the plunger, and a sealing member provided between the plunger and a cylinder bore for sealing oil leaked from the pump chamber to a chamber surrounding the pump chamber, wherein oil in the oil chamber is supplied from the outside of the high pressure fuel pump.

Abstract: The present invention provides an axial plunger pump which does not need bellows by restricting fuel to a cylinder bore configuring a pump portion and by lubricating the other portion with oil. The high pressure fuel pump comprises a plunger reciprocating according to a shaking movement of a swash plate, a cylinder block forming a pump chamber together with the plunger, and a sealing member provided between the plunger and a cylinder bore for sealing oil leaked from the pump chamber to a chamber surrounding the pump chamber, wherein oil in the oil chamber is supplied from the outside of the high pressure fuel pump.

Abstract: The present invention provides an axial plunger pump which does not need bellows by restricting fuel to a cylinder bore configuring a pump portion and by lubricating the other portion with oil. The high pressure fuel pump comprises a plunger reciprocating according to a shaking movement of a swash plate, a cylinder block forming a pump chamber together with the plunger, and a sealing member provided between the plunger and a cylinder bore for sealing oil leaked from the pump chamber to a chamber surrounding the pump chamber, wherein oil in the oil chamber is supplied from the outside of the high pressure fuel pump.

Abstract: An axial plunger pump according to the present invention is constructed so as to comprise a shaft having a swash plate effecting swing motion and transmitting driving force from the outside, plungers each reciprocating by the swing motion of the swash plate, a cylinder block having cylinders formed so as to open on the side of the swash plate and inserting therein the plungers and having passages for supplying fuel to the cylinders, a body combined with the cylinder block to enclose the swash plate, and sealing members arranged between the plungers and the cylinders on the swash plate side of the passages formed in the cylinder block for sealing gaps between the plungers and the cylinders, respectively.