Abstract: To suppress the possibility that a body-side holding member comes into contact with a joint portion 92 of a damper mechanism 9. damper cover that is arranged on an upstream side of a pressurizing chamber and is attached to a body to form a damper chamber, a damper mechanism that is arranged in the damper chamber, and a body-side holding member that holds the damper mechanism from the body side are provided. The body-side holding member includes a bottom surface in contact with the body and a flexible portion formed along an urging direction by being urged downward from the damper cover toward the body.

Abstract: Provided is a high-pressure fuel pump that ensures oil tightness even at high fuel pressure and has a small and lightweight inexpensive discharge valve structure. Therefore, a high-pressure fuel pump according to the present invention includes: a discharge valve arranged on a discharge side of a pressurizing chamber; a discharge valve seat on which the discharge valve is seated; and a facing member configured independently as a separate member from the discharge valve seat and located on an opposite side of the discharge valve seat with the discharge valve interposed therebetween, in which a stroke direction regulating portion that regulates displacement of the discharge valve in a stroke direction is formed on a tapered surface of the facing member.

Abstract: To suppress the possibility that a body-side holding member comes into contact with a joint portion 92 of a damper mechanism 9. damper cover that is arranged on an upstream side of a pressurizing chamber and is attached to a body to form a damper chamber, a damper mechanism that is arranged in the damper chamber, and a body-side holding member that holds the damper mechanism from the body side are provided. The body-side holding member includes a bottom surface in contact with the body and a flexible portion formed along an urging direction by being urged downward from the damper cover toward the body.

Abstract: There is provided a discharge valve mechanism provided at an outlet of a pressurizing chamber of a high-pressure fuel supply pump that aims to reduce a backflow amount of fuel from a discharge valve and to prevent cavitation erosion. There are provided a discharge valve disposed on a discharge side of a pressurizing chamber, a discharge valve seat that closes a discharge side flow passage of the pressurizing chamber by seating the discharge valve, and a discharge valve spring that presses the discharge valve toward the discharge valve seat. It is configured such that, in a case where a minimum seat diameter of a seat portion in which the discharge valve is seated on the discharge valve seat is set to D and a spring force of the discharge valve spring at a time of setting is set to F, a coefficient K obtained by dividing the spring force F by the minimum seat diameter D is set to be 0.2 or more.

Abstract: There is provided a discharge valve mechanism provided at an outlet of a pressurizing chamber of a high-pressure fuel supply pump that aims to reduce a backflow amount of fuel from a discharge valve and to prevent cavitation erosion. There are provided a discharge valve disposed on a discharge side of a pressurizing chamber, a discharge valve seat that closes a discharge side flow passage of the pressurizing chamber by seating the discharge valve, and a discharge valve spring that presses the discharge valve toward the discharge valve seat. It is configured such that, in a case where a minimum seat diameter of a seat portion in which the discharge valve is seated on the discharge valve seat is set to D and a spring force of the discharge valve spring at a time of setting is set to F, a coefficient K obtained by dividing the spring force F by the minimum seat diameter D is set to be 0.2 or more.

Abstract: A fuel pump includes an electromagnetically driven intake valve mechanism, a pump housing, a discharge valve, an opening, a seal member, and a first relief passage. The relief valve mechanism has a relief valve, a relief valve seat contacting the relief valve when the relief valve is closed and a relief spring biasing the relief valve against the relief valve seat. A second relief passage, communicating the first relief passage and a hole formed in the relief seat, is formed between the seal member and the relief valve seat. The relief valve seat, the relief valve, and the relief spring are arranged in this order beginning from the open end side.

Abstract: Provided is a high-pressure fuel pump that ensures oil tightness even at high fuel pressure and has a small and lightweight inexpensive discharge valve structure. Therefore, a high-pressure fuel pump according to the present invention includes: a discharge valve arranged on a discharge side of a pressurizing chamber; a discharge valve seat on which the discharge valve is seated; and a facing member configured independently as a separate member from the discharge valve seat and located on an opposite side of the discharge valve seat with the discharge valve interposed therebetween, in which a stroke direction regulating portion that regulates displacement of the discharge valve in a stroke direction is formed on a tapered surface of the facing member.

Abstract: A fuel pump includes an electromagnetically driven intake valve mechanism, a pump housing, a discharge valve, an opening, a seal member, and a first relief passage. The relief valve mechanism has a relief valve, a relief valve seat contacting the relief valve when the relief valve is closed and a relief spring biasing the relief valve against the relief valve seat. A second relief passage, communicating the first relief passage and a hole formed in the relief seat, is formed between the seal member and the relief valve seat. The relief valve seat, the relief valve, and the relief spring are arranged in this order beginning from the open end side.

Abstract: A high-pressure fuel supply pump in which a relief valve mechanism is not detached by a force generated by a differential pressure between an inlet side and an output side of a relief valve mechanism is obtained. According to the present invention, in order to obtain the high-pressure fuel supply pump, the relief valve mechanism of the high-pressure fuel supply pump is oriented from a downstream side of a discharge valve to an upstream side of the discharge valve, and the output side of the relief valve mechanism is inserted from the upstream side of the discharge valve into the pump housing, and the relief valve mechanism is fixed with press fitting. Therefore, a force exerted by the differential pressure between the inlet side pressure and the output side pressure of the relief valve mechanism is exerted in a direction in which the relief valve mechanism is inserted, so that the relief valve mechanism can be prevented from being detached.

Abstract: An object is to suppress cavitation generated at a distal end portion of a seat face when a valve body and a seat portion collide with each other. In a relief valve of a fuel pump, an intersection between the seat face and a flow channel hole is formed at a position more distant than the seat portion formed of the valve body in a valve closing state and the seat face in order to suppress generation of cavitation bubbles when the valve body improves and releases high-pressure fuel.

Abstract: An object is to suppress cavitation generated at a distal end portion of a seat face when a valve body and a seat portion collide with each other. In a relief valve of a fuel pump, an intersection between the seat face and a flow channel hole is formed at a position more distant than the seat portion formed of the valve body in a valve closing state and the seat face in order to suppress generation of cavitation bubbles when the valve body improves and releases high-pressure fuel.

Abstract: Provided is a solution to a problem on a discharge valve mechanism disposed at an exit of a pressurizing chamber of a high-pressure fuel supply pump, that is, an occurrence of a backward flow of the fuel concentrates on a limited fuel passage, leading to a higher fuel flow rate, and this easily induces the occurrence of cavitation, and collapse of the generated cavitation might damage a seat surface, making it difficult to maintain valve functions. The present invention provides a valve mechanism including a seat member having a seat section, a valve body configured to attach to or detached from the seat section, and a housing member arranged on an outer peripheral side of the seat member. A first fluid flow-path is formed to connect an inner peripheral side and an outer peripheral side of the seat section in a case where the valve is detached from the seat section.

Abstract: A high-pressure fuel supply pump in which a relief valve mechanism is not detached by a force generated by a differential pressure between an inlet side and an output side of a relief valve mechanism is obtained. According to the present invention, in order to obtain the high-pressure fuel supply pump, the relief valve mechanism of the high-pressure fuel supply pump is oriented from a downstream side of a discharge valve to an upstream side of the discharge valve, and the output side of the relief valve mechanism is inserted from the upstream side of the discharge valve into the pump housing, and the relief valve mechanism is fixed with press fitting. Therefore, a force exerted by the differential pressure between the inlet side pressure and the output side pressure of the relief valve mechanism is exerted in a direction in which the relief valve mechanism is inserted, so that the relief valve mechanism can be prevented from being detached.