Hitachi Automotive Systems, Ltd.

Hitachi, Ltd.

Hitachi Astemo Ltd.

Hitachi Car Engineering Co., Ltd.

Satoshi Usui

Hiroyuki Yamada

Kenichiro Tokuo

Masayuki Suganami

Shingo Tamura

Minoru Hashida

Atsuji Saito

Katsumi Miyazaki

Tatsuo Kawano

Masami Abe

Masahiko Hayatani

Atsushi Hohkita

Masamichi Yagai

Toru Onose

Yuta Saso

Shunsuke Aritomi

Hiroshi Odakura

Kazuaki Tokumaru

Sunao Takahashi

Moritsugu Akiyama

Kenichirou Tokuo

Ryo Kusakabe

Hideki Machimura

Shigehiko Omata

Akihiro Munakata

Masashi Nemoto

Masahiro Toyohara

Osamu Mukaihara

Kiyotaka Ogura

Masayoshi Kotaki

Syunsuke Aritomi

Junichi Shimada

Eiichi Kubota

Atsushi Takaoku

Daisuke Kitajima

Shigenori Tahara

Takefumi Yamamura

Arata Kagiyama

Tohru Himoto

Masaru Kawai

Hiroshi Horie

Masami Hitachi Car Eng Co Ltd Abe

The present invention provides a fuel pump capable of discharging fuel at high pressure and suppressing sticking between a plunger and a cylinder. A high-pressure fuel supply pump includes a plunger that reciprocates, a cylinder in which a guide hole for guiding a reciprocating motion of the plunger extends in an axial direction, and a pump body including a third room (cylinder insertion hole) into which the cylinder is press-fitted, and a pressurizing chamber that communicates with the third room and has a volume increased or decreased by the reciprocating motion of the plunger. The pressure of a fixed gap generated between the cylinder and the pump body is set to be equal to or higher than pressure of a sliding gap generated between the plunger and the cylinder.

Fuel pump

The present invention provides a fuel pump capable of preventing the occurrence of cavitation near a seat member in a valve mechanism. The fuel pump includes a plunger adapted to reciprocate, a pressurizing chamber adapted to increase and decrease its volumetric capacity through the reciprocation of the plunger, and a relief valve mechanism adapted to return a fuel to the pressurizing chamber. The relief valve mechanism includes a relief valve, and a seat member having a valve contact portion for seating the relief valve thereon. The relief valve is disposed closer to the plunger than the seat member. The seat member has an annular groove portion which forms a space communicating with the pressurizing chamber, between the annular groove portion and a second chamber (a fixing portion) surrounding the outer peripheral surface of the seat member. The space is provided at a position farther from the plunger than the valve contact portion.

A fuel pump includes a damper, a suction valve chamber, a pressurization chamber, a relief valve chamber, a relief valve mechanism, and a shock wave absorber. The shock wave absorber is provided in the relief valve chamber, and is disposed to face the relief valve holder on the downstream side in the direction in which the relief valve holder moves when the relief valve mechanism is released.

A coil component of an electromagnetic valve is made compact to achieve both low cost and improvement in sound vibration performance. Therefore, a high-pressure fuel pump of the present invention includes: a coil; a magnetic corethat is arranged on a side opposite to a pressurizing chamberwith respect to a movable coreand attracts the movable corewhen the coilis energized; a yokearranged on a radially outer side of the coil; a cover portionthat covers the coilfrom an axially outer side; and a molded portionthat covers a radially outer side of the yokeand an axially outer side of the cover portion

The present invention provides a fuel pump capable of suppressing sticking of a plunger. The fuel pump of the present invention includes a plungerthat reciprocates, a cylinderin which a guide holethat guides the reciprocating motion of the plungerextends in the axial direction, and a pump bodythat holds the cylinder. The pump bodyincludes a cylinder insertion holeinto which the cylinderis inserted, and a pressurizing chamberthat communicates with the cylinder insertion holeand has a volume increased or decreased by the reciprocating motion of the plunger. The cylinderincludes a press-fitting portionpress-fitted into the inner peripheral surface of the cylinder insertion hole, and a grooveformed at a position corresponding to the press-fitting portionon the inner peripheral surface of the guide hole

An object of the present invention is to prevent generation of wear at a rod collision portion in an electromagnetic intake valve of a high-pressure fuel supply pump by reducing inclinations of the intake valve and a rod. A structure of the electromagnetic intake valve of the high-pressure fuel supply pump is configured as follows. A seat portion of an intake valve and a guide portion of a rod are configured as an integral part, and further, a rod guide is made to have a sufficiently long length so that it is possible to perform guide at one portion. Further, the intake valve seat portion and a surface where the rod collides with the intake valve are formed on the same plane.

High-pressure fuel supply pump provided with electromagnetic intake valve

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.

High-pressure fuel pump

Provided is a high-pressure fuel supply pump capable of reducing a manufacturing cost of a part for holding a metal damper. The high-pressure fuel supply pump includes a pump bodyhaving a pressurizing chambertherein, a damper coverforming a damper chambertogether with the pump bodyon the upstream side of the pressurizing chamber, a metal damperthat is disposed in the damper coverand formed by laminating two metal diaphragms, and a first holding memberthat is disposed in the damper chamberand presses and holds the metal damperfrom one side. The first holding memberincludes a first regulation portion that regulates the radial movement of the metal damper, and a second regulation portion that regulates the radial movement of the first holding memberin the damper chamber. At a position of the second regulation portion, a flow path is formed which allows the fuel in the damper chamberto circulate to both surfaces of the metal damper

High-pressure fuel supply pump

A high pressure fuel pump includes a pump housing, pressure and damper chambers, a metal diaphragm, a press-fitted portion, and a weld portion. The pressure chamber is provided in the pump housing. The damper chamber is formed by the pump housing and a damper cover. The metal diaphragm damper is arranged in the damper chamber. At the press-fitted portion, an annular surface of the damper cover is press fitted to an annular surface of the pump housing. The weld portion fixes the damper cover to the pump housing at an entire circumference of the press-fitted portion.

Mechanism for restraining fuel pressure pulsation and high pressure fuel supply pump of internal combustion engine with such mechanism

An object of the present invention is to supply a high-pressure fuel supply pump capable of holding a spring holding member while reducing the height of the pump body. A high-pressure fuel supply pump is provided with a pump body for forming a pressurizing chamber at an inner wall portion, and a flange portion for fixing the pump body to a high-pressure fuel supply pump mounting portion. The high-pressure fuel supply pump is provided with a cylinder and a spring holding member. The cylinder is inserted into a hole portion of the pump body from a lower side and in which the pressurizing chamber is formed further above an uppermost end surface. The spring holding member has an outer peripheral portion press-fitted and fixed to the pump body and a holding portion holding a spring portion for biasing the pump body between the outer peripheral portion and the inner peripheral portion. A spring-side lowest end portion of the holding surface of the spring holding member is disposed above the lowermost end portion of the flange portion.

To increase a valve-opening pressure at which a pressure relief valve is opened in order to deal with a higher pressure of the fuel, a large pressure relief valve is installed in a high-pressure fuel supply pump. This upsizes the high-pressure fuel supply pump. A pressure relief valve is installed in a discharge joint. This can provide a high-pressure fuel supply pump that is not large too much and sufficiently performs a relief function by efficiently using the excessive space in the pump even when the fuel pressure is increased.

Provided is a high-pressure fuel pump which can fix a cylinder to a pump body using a simple structure, and can reduce a displacement amount inward in a radial direction of the cylinder. A high-pressure fuel pump includes a pump body which is formed with a pressing chamber and a cylinder which is inserted in a hole formed in the pump body. The cylinder is swaged to the hole by pressing a convex portion on an outside in a radial direction to fit into the hole on an opposite side to the pressing chamber, by screwing a formed screw thread into the hole, or by being swaged with the opposite side to the pressing chamber. The cylinder is formed with a clearance in the radial direction with respect to the hole of the pump body all over a region from a bonding portion to an upper end.

A pump for supplying high-pressure includes a plunger, a cylinder, a body, and a holder. The uppermost end surface of the cylinder is an end of the cylinder that is closest to the pressurizing chamber. A first gap formed between the outer periphery of the cylinder and the body in the radial direction is smaller than a second gap formed in the radial direction between the inner diameter of the pressurizing chamber and the outer diameter of the plunger. A radial gap is formed in an entire area of the cylinder in an axial direction thereof.

Pump for supplying high-pressure fuel

It is an object of the present invention to provide a high-pressure fuel supply pump having a pump body capable of improving corrosion resistance and weldability and being manufacturable by forging. Therefore, in the high-pressure fuel supply pump having a metal pump body forming a pressurizing chamber, the pump body is made of a steel material containing 12% to 18% of Cr and 3% to 7% of Ni, and the pump body has a forging surface on a part of the outer peripheral surface.

A fuel pump includes an intake valve unit which is provided between a low-pressure chamber and a pressurizing chamber. The intake valve unit includes an intake valve configured to move in an axial direction of the intake valve unit and a valve stopper arranged between the intake valve and the pressurizing chamber. A plurality of fuel passages configured to allow fuel to communicate between the low-pressure chamber and the pressurizing chamber are formed on a radially outward of an outer peripheral surface of the valve stopper.

Growing community of inventors

Hitachinaka, Japan

Satoshi Usui