Abstract: A mechanism for reducing pressure pulsation includes a pair of metal dampers formed by joining two disk-shaped metal diaphragms over an entire circumference and forming a hermetically sealed space inside a joined portion. Gas is sealed in the aforementioned hermetically sealed space of the damper, and a pair of pressing members give pressing forces to both outer surfaces of the aforementioned metal dampers at a position at an inner diameter side from the joined portion. The mechanism is unitized, with the pair of pressing members being connected in a state in which they sandwich the metal damper.

Abstract: Provided is a high-pressure fuel pump in which responsiveness of closing a suction valve can be maintained even when the high-pressure fuel pump is increased in pressure or capacity of the high-pressure fuel pump is increased, thereby ensuring discharge efficiency. Therefore, the high-pressure fuel pump includes the rod that urges the suction valve in the valve opening direction, the mover that drives the rod in the valve closing direction, and the solenoid that generates a magnetic attraction force for moving the mover in the valve closing direction. After the suction valve starts moving from the suction valve closing position in the valve opening direction, the rod reaches the suction valve closing position and further moves in the valve opening direction.

Abstract: A high-pressure fuel pump capable of reducing the number of components and decreasing the manufacturing cost by processing of a pump body is provided. The high-pressure fuel pump includes a metal damper, a pump body in which a damper housing that houses the metal damper is formed, a damper cover attached to the pump body, covering the damper housing, and holding the metal damper between the pump body and the damper cover, and a holding member fixed to the damper cover and holding the metal damper from a side opposite to the damper cover. The holding member is provided with an elastic portion that urges the pump body so that the metal damper is urged toward the damper cover.

Abstract: Responsiveness of an electromagnetic flow-rate control valve provided for closing a suction valve is improved and a discharge flow rate is controlled to a desired value. A flow-rate control valve includes a fixed core arranged on an inner circumferential side of a coil, a yoke arranged on an outer circumferential side of the coil, and a cover portion opposed to the coil in an axial direction, in which the fixed core has an enlarged portion in contact with the cover portion in the axial direction and enlarging toward the coil, and the cover portion is regulated in the axial direction only by a contact portion with the fixed core.

Abstract: Provide is a high-pressure fuel pump capable of improving the degree of freedom of layout of members to be attached to a pump body and a producing method thereof. Therefore, the high-pressure fuel pump includes the suction joint that sucks fuel, the pump body formed with the pressurizing chamber that pressurizes the fuel sucked from the suction joint, and the discharge joint that discharges the fuel pressurized in the pressurizing chamber. The pump body is formed so that at least a part of the side surface portion thereof becomes a cylindrical portion or a polygonal shape portion. At least one of the discharge joint and the suction joint may be fixed on the inner peripheral side with respect to the outermost peripheral portion of the cylindrical portion or the polygonal shape portion of the side surface portion.

Abstract: An object of the present invention is to obtain a high pressure fuel supply pump capable of reducing pressure pulsation that occurs in a low pressure pipe, preventing damage to the low pressure pipe, or reducing noise due to vibrations of the low pressure pipe.

Abstract: A mechanism for reducing pressure pulsation includes a pair of metal dampers formed by joining two disk-shaped metal diaphragms over an entire circumference and forming a hermetically sealed space inside a joined portion. Gas is sealed in the aforementioned hermetically sealed space of the damper, and a pair of pressing members give pressing forces to both outer surfaces of the aforementioned metal dampers at a position at an inner diameter side from the joined portion. The mechanism is unitized, with the pair of pressing members being connected in a state in which they sandwich the metal damper.

Abstract: A high-pressure fuel pump includes a pump body, a plunger, a retainer, a spring that is configured to energize the plunger in a direction opposite to a direction of the pressurizing chamber, and a tappet covering the retainer from a side of an end portion of the retainer and the plunger. The retainer is provided with a projection portion protruding to a side of the tappet. The projection portion is separated from the tappet by a predetermined distance along an axial direction of the plunger.

Abstract: A high pressure fuel supply pump includes: an electromagnetic suction valve that adjusts an amount of fuel sucked into a pressuring chamber; a discharge valve that discharges the fuel from the pressuring chamber; and a plunger that makes a reciprocating motion in the pressuring chamber. The electromagnetic suction valve includes an electromagnetic coil, a suction valve, and a movable portion that is able to close the suction valve by a magnetic force when the electromagnetic coil is energized. The movable portion includes an anchor that is driven to close the suction valve by the magnetic force and stops at a fixed member, and a rod that is driven with the anchor and is able to move even after the anchor stops. The electromagnetic suction valve includes a first and second springs that bias the suction valve in closed and open direction, respectively, and a third spring in the rod.

Abstract: A mechanism for reducing pressure pulsation includes a pair of metal dampers formed by joining two disk-shaped metal diaphragms over an entire circumference and forming a hermetically sealed space inside a joined portion. Gas is sealed in the aforementioned hermetically sealed space of the damper, and a pair of pressing members give pressing forces to both outer surfaces of the aforementioned metal dampers at a position at an inner diameter side from the joined portion. The mechanism is unitized, with the pair of pressing members being connected in a state in which they sandwich the metal damper.

Abstract: A high-pressure fuel pump includes a pump body, a plunger, a retainer, a spring that is configured to energize the plunger in a direction opposite to a direction of the pressurizing chamber, and a tappet covering the retainer from a side of an end portion of the retainer and the plunger. The retainer is provided with a projection portion protruding to a side of the tappet. The projection portion is separated from the tappet by a predetermined distance along an axial direction of the plunger.

Abstract: A mechanism for reducing pressure pulsation includes a pair of metal dampers formed by joining two disk-shaped metal diaphragms over an entire circumference and forming a hermetically sealed space inside a joined portion. Gas is sealed in the aforementioned hermetically sealed space of the damper, and a pair of pressing members give pressing forces to both outer surfaces of the aforementioned metal dampers at a position at an inner diameter side from the joined portion. The mechanism is unitized, with the pair of pressing members being connected in a state in which they sandwich the metal damper.

Abstract: A high-pressure fuel supply pump having a normally-closed type electromagnetically-driven inlet valve mechanism supporting a large capacity and causing least sound is provided. A valve member having a seat surface that comes into abutment with an inlet valve seat; and a plunger rod positioned on the seat surface side of the valve member and configured to operate the valve member by a magnetic attraction force are provided, and a protector configured to face a surface of the valve member on the surface opposite to the seat surface with a gap therebetween when the plunger rod makes a full stroke in the valve-open direction of the valve member and an anchor for driving the plunger rod comes into contact with a stopper is provided.

Abstract: A mechanism for reducing pressure pulsation includes a pair of metal dampers formed by joining two disk-shaped metal diaphragms over an entire circumference and forming a hermetically sealed space inside a joined portion. Gas is sealed in the aforementioned hermetically sealed space of the damper, and a pair of pressing members give pressing forces to both outer surfaces of the aforementioned metal dampers at a position at an inner diameter side from the joined portion. The mechanism is unitized, with the pair of pressing members being connected in a state in which they sandwich the metal damper.

Abstract: A mechanism for reducing pressure pulsation includes a pair of metal dampers formed by joining two disk-shaped metal diaphragms over an entire circumference and forming a hermetically sealed space inside a joined portion, with gas being sealed in the aforementioned hermetically sealed space of the damper, has a pair of pressing members which give pressing forces to both outer surfaces of the aforementioned metal dampers at a position at an inner diameter side from the joined portion, and is unitized with the pair of pressing members being connected in a state in which they sandwich the metal damper.

Abstract: A high-pressure fuel pump is comprises of: a plunger which slidably fits to a cylinder and reciprocates for pressurizing and discharging a fuel taken in a pressurizing chamber; an inlet valve device for taking in a fuel into the pressurizing chamber; an outlet valve device for discharging the pressurized fuel from the pressurizing chamber; and a communicating pass which comprises a hole or a groove formed in the cylinder, and communicates between a pressurized fuel area and a gap between the cylinder and the plunger.

Abstract: In a conventional high-pressure fuel pump, the interference fit part between a plunger and a retainer comes loose with time due to environmental factors and this reduces the clearance between the retainer and a tappet more than necessity, resulting in increase in the contact face pressure between the plunger and a cylinder when a side force acts on the plunger, which causes seizure between the plunger and the cylinder. In this invention, a protrusion protruding toward the tappet is provided around the through-hole for press-fitting the plunger, the through-hole provided in the center portion of the retainer. Since the clearance between the retainer and the tappet can sufficiently be kept even if the joint between the retainer and the plunger comes loose, the seizure between the plunger and the cylinder and the breakage of the plunger are less likely to occur even if the side force acts on the retainer.

Abstract: A mechanism for reducing pressure pulsation includes a pair of metal dampers formed by joining two disk-shaped metal diaphragms over an entire circumference and forming a hermetically sealed space inside a joined portion, with gas being sealed in the aforementioned hermetically sealed space of the damper, has a pair of pressing members which give pressing forces to both outer surfaces of the aforementioned metal dampers at a position at an inner diameter side from the joined portion, and is unitized with the pair of pressing members being connected in a state in which they sandwich the metal damper.

Abstract: To obtain a small and high performance damper mechanism which reduces pressure pulsation in low pressure-side fuel in the high pressure fuel pump in a high pressure fuel supply system or a high pressure fuel pump provided with the small and high performance damper mechanism. Two metal diaphragms are welded together over the entire circumference to obtain a metal diaphragm assembly (also referred to as “double metal diaphragm damper”). The whole or part of the portion of the metal diaphragm assembly other than the weld (for example, the portion inside the weld) is clamped by a pressing member and thereby the assembly is secured in a housing enclosure. The housing enclosure may be formed integrally with the body of a high pressure pump.

Abstract: A high-pressure fuel supply pump having a fuel relief path for connecting a high-pressure fuel path downstream of a discharge valve for discharging fuel pressurized in a pressurizing chamber to a low-pressure fuel path upstream of an inlet valve or the pressurizing chamber, a check valve being provided in the fuel relief path as a relief valve for allowing the fuel to flow only to the low-pressure fuel path or the pressurizing chamber, wherein an energy attenuating mechanism is provided in a discharge path on a side facing the discharge valve upstream of the relief valve in the fuel relief path so as to prevent an instantaneous pressure rise caused in the discharge path from propagating to the relief valve.