Abstract: A pump device includes: a rotor unit that exerts a pumping action on fluid; a housing for defining a suction port, a discharge port, and a storage chamber that stores the rotor unit; and a rotary shaft that is combined with the rotor unit and protrudes outside the housing and that rotates about a predetermined axis line. The housing includes: a bottomed cylindrical housing body integrally having a joint wall that is joined to an application object, an outer peripheral wall that defines the storage chamber in cooperation with the joint wall, and a spigot joint part that protrudes from the joint wall in the axis line direction and that is fitted to the application object; and a plate-like housing cover that is combined with the housing body in order to close the storage chamber.

Abstract: The disclosure provides a pump device capable of suppressing hydraulic amplitude and reducing noise or vibration associated with hydraulic amplitude while simplifying the structure. The pump device includes: a housing which defines a suction port, a discharge port, and an accommodation chamber; and a pump unit which is arranged in the accommodation chamber and which defines a pump chamber that expands and contracts to exert a pumping action including a suction stroke and a pressurization and discharge stroke on a fluid. The housing includes an air introduction hole that is opened to introduce air into the pump chamber at a predetermined opening timing immediately before the suction stroke is completed.

Abstract: The disclosure provides a pump device capable of suppressing hydraulic amplitude and reducing noise or vibration associated with hydraulic amplitude while simplifying the structure. The pump device includes: a housing which defines a suction port, a discharge port, and an accommodation chamber; and a pump unit which is arranged in the accommodation chamber and which defines a pump chamber that expands and contracts to exert a pumping action including a suction stroke and a pressurization and discharge stroke on a fluid. The housing includes an air introduction hole that is opened to introduce air into the pump chamber at a predetermined opening timing immediately before the suction stroke is completed.

Abstract: Provided are an impeller and a centrifugal pump that can be simplified in structure and reduced in weight and cost, and that can be integrally molded by a mold or the like. In a centrifugal pump including a housing having an inlet, an outlet and an impeller chamber, an impeller is disposed in the impeller chamber and is rotationally driven by a driving shaft. The impeller includes: a shaft part connected to the driving shaft to rotate about an axis line extending toward the inlet; blades protruding radially outward from an outer periphery of the shaft part; and an annular shroud plate continuous with the blades so as to cover a tip side area of the blades in order to be disposed adjacent to an inner wall of the housing on the inlet side.

Abstract: A check valve for opening/closing intake-side communication passages through which fuel passes, includes a pump body including a partition wall with the communication passages formed therein, a valve body supported by the partition wall, made of a flexible material, and formed into a plate shape, and a valve seat provided around opening portions of the communication passages on the partition wall and including a seat surface to abut against the valve body when the valve is closed, the seat surface including a groove having an opening-portion-side wall surface lying on an upstream side and an outer-side wall surface lying on a downstream side, the upstream and downstream sides being sides in a direction in which fluid passes between the valve body and the seat surface when the valve is opened, the outer-side wall surface having a gentler slope than a slope of the opening-portion-side wall surface.

Abstract: Provided are an impeller and a centrifugal pump that can be simplified in structure and reduced in weight and cost, and that can be integrally molded by a mold or the like. In a centrifugal pump including a housing having an inlet, an outlet and an impeller chamber, an impeller is disposed in the impeller chamber and is rotationally driven by a driving shaft. The impeller includes: a shaft part connected to the driving shaft to rotate about an axis line extending toward the inlet; blades protruding radially outward from an outer periphery of the shaft part; and an annular shroud plate continuous with the blades so as to cover a tip side area of the blades in order to be disposed adjacent to an inner wall of the housing on the inlet side.

Abstract: A check valve for opening/closing intake-side communication passages through which fuel passes, includes a pump body including a partition wall with the communication passages formed therein, a valve body supported by the partition wall, made of a flexible material, and formed into a plate shape, and a valve seat provided around opening portions of the communication passages on the partition wall and including a seat surface to abut against the valve body when the valve is closed, the seat surface including a groove having an opening-portion-side wall surface lying on an upstream side and an outer-side wall surface lying on a downstream side, the upstream and downstream sides being sides in a direction in which fluid passes between the valve body and the seat surface when the valve is opened, the outer-side wall surface having a gentler slope than a slope of the opening-portion-side wall surface.

Abstract: Provided is a hydraulic circuit for transmissions with which, while suppressing the hydraulic circuit from becoming complicated, it is possible to suppress an operational failure and a drop in the oil pressure of the hydraulic circuit, and to stabilize an oil pressure in the hydraulic circuit. The CVT 1 includes a part to be lubricated and a hydraulic control part for controlling transmission. The hydraulic circuit for transmissions includes a hydraulic oil pathway 3 for supplying oil from the pump apparatus 8 to the hydraulic control part 2, and a lubricating oil pathway 5 for supplying oil containing an air bubble to the part to be lubricated 4. The pump apparatus 8 includes a multi-stage trochoid pump 9 and has an air bubble-containing oil discharging part 11 for discharging the oil containing an air bubble to the first stage trochoid pump part 6. The air bubble-containing oil discharging part 11 is connected to the lubricating oil pathway 5.

Abstract: The CVT 1 includes a part to be lubricated and a hydraulic control part for controlling transmission. The hydraulic circuit for transmissions includes a first hydraulic oil pathway for supplying oil from the pump apparatus to the hydraulic control part, and a second lubricating oil pathway for supplying oil containing an air bubble to the part to be lubricated. The pump apparatus includes a multi-stage trochoid pump and has an air bubble-containing oil discharging part for discharging the oil containing an air bubble to the first stage trochoid pump part. The air bubble-containing oil discharging part is connected to the second lubricating oil pathway. The second stage trochoid pump part increases pressure of the oil discharged from the first stage trochoid pump part, and discharges it from the high-pressure oil discharging part. The first hydraulic oil pathway is connected to the high-pressure oil discharging part.

Abstract: A valve apparatus is small, and regulates a fuel amount by restricting a lift amount of a valve. A columnar portion is formed on a pump body. The columnar portion is inserted into a check valve and a washer formed with a protruding portion which protrudes outward from a flange portion, and the check valve and washer are attached or fixed to the pump body by subjecting a tip end of the columnar portion to thermal caulking or the like. An outer diameter of the protruding portion is set to be relatively smaller than an outer diameter of the flange portion such that when the check valve is sandwiched between the protruding portion and pump body, the check valve contacts an outer peripheral edge of the flange portion when the check valve opens. As a result, a lift amount of the valve can be restricted, and a flow rate of fuel passing through a passage can be maintained at a constant level.

Abstract: The present invention provides a valve apparatus which is small and reasonably priced, and with which a fuel amount can be regulated by restricting the lift amount of a valve. A columnar portion 60 is formed in a body 16, the columnar portion 60 is inserted into a valve 44, 46 and a washer 62 formed with a protruding portion 72 which protrudes outward from a flange portion 64, and the check valve 44, 46 and washer 62 are attached or fixed to the pump body 16 by subjecting the tip end of the columnar portion 60 to thermal caulking or the like. The outer diameter of the protruding portion 72 is set to be relatively smaller than the outer diameter of the flange portion 64 such that when the check valve 44, 46 is sandwiched between the protruding portion 72 and pump body 16, the check valve 44, 46 contacts an outer peripheral edge 70 of the flange portion 64 when the check valve 44, 46 opens.

Abstract: A fuel cell system in which water can be accurately supplied in accordance with the flow rate of fuel gas supplied to the reformer to allow efficient reforming without using a flow meter measuring the flow rate of water. In the fuel cell system in which fuel gas is supplied to a reformer where steam reforming is carried out to convert the fuel gas to hydrogen rich gas, and the hydrogen rich gas is supplied to a fuel cell unit to generate electricity, the pump that supplies water to the reformer is a plunger pump in which the rate of discharge of water is proportional to the rate of rotation of the motor that drives the pump. Also the fuel cell system includes a gas flow rate sensor to measure the flow rate of fuel gas supplied to the reformer, and a controller that controls the rate of rotation of the motor in accordance with the value of flow rate measured by the gas flow rate sensor.

Abstract: There are provided a plunger pump and method of controlling discharge of the pump capable of obtaining a desired compression rate, changing a discharge amount with ease without changing a stroke of the plunger and/or the inner diameter of a sliding hole of the plunger, and discharging a constant amount of fluid with accuracy while preventing the fluid from leaking.

Abstract: A water pump includes an engage mechanism 25 which is disposed between a pump body 21 and the end portion of a pump shaft 23 opposite to the side where an impeller 22 is attached, while engaging the pump shaft to the pump body against the urging force of the urging member which urges a mechanical seal 24. The engage mechanism includes an annular member 26 which is rotatably fitted to the pump shaft 23 while contacting the pump body 21, and a cylindrical engage pin 27 which pierces the pump shaft 23 in the diameter direction while sandwiching the annular member 26 with the pump body 21.

Abstract: The object is to provide a water pump which machining accuracy and assembling accuracy can be easily improved.

Abstract: A lubricating oil supplying device allows for the oil discharge amount to be more finely controlled by provision of many outlet ports, and by reducing the influence of vibration. Therefore, a spool valve unit and a pump are separately formed. The spool valve unit includes an open-close spool valve and a solenoid for controlling operation of this spool valve. Plural inlet passages and an outlet passage are formed in the spool valve. The spool valve opens or closes the inlet passages, and oil from the pump is introduced into these inlet passages. One side of the outlet passage communicates with the inlet passages, and the other side communicates with an engine. A passage for introducing the oil from an oil tank to a pump chamber is formed in the solenoid. When the solenoid is turned “OFF”, communication between the return passage and the inlet passages is interrupted by the spool valve, and the oil is discharged from the pump to the plural inlet passages.

Abstract: A fuel pump which has excellent heat resistance and salt resistance, is low in cost and light in weight, and which is free from fuel leakage. The fuel pump has a bottom body formed of a thermosetting resin such as bakelite material which has heat resistance and strength, and a top body and a cover formed of a thermoplastic resin. The top body and the cover 16 are assembled with a seal member such as a gasket held between the top body and the cover, and the top body and the bottom body 12 are fixed together by a fixing element. Thereby, the main body portions of the fuel pump are constituted of resin.