The present invention relates to a rotary barrel pump where the pivot connection between barrel (6) and casing (15) is provided by the distinct guide and centering means.

A valve piston pump body device of water flosser includes a front bracket shell equipped with a back bracket shell. A pump body is installed at the middle-upper end of the cavity between the front bracket shell and the back bracket shell. A motor is installed at the middle-lower end of the cavity between the front bracket shell and the back bracket shell. The rotating shaft at the upper end of the motor is equipped with motor teeth. A first metal shaft is arranged in the hole of the cavity between the front bracket shell and the back bracket shell. A driving gear is installed on the first metal shaft and the driving gear and the motor teeth are mutually engaged. A one-way valve piston device is used.

A swash-plate type piston pump includes a cylinder block configured to be rotated with rotation of a driving shaft, a plurality of pistons accommodated in a plurality of cylinders provided in the cylinder block, a swash plate configured to reciprocate the piston so that a volume chamber of the cylinder is expanded/contracted with the rotation of the cylinder block, an biasing mechanism configured to bias the swash plate in a direction where a tilting angle is made larger, a control pin configured to drive the swash plate in a direction where the tilting angle is made smaller in accordance with a rise in a load pressure of a pressure chamber, and a discharge channel configured to discharge the load pressure of the pressure chamber.

An engine fuel control system includes a main pump which receives fuel from a low pressure source and delivers the fuel at a first high pressure, and a variable displacement augmenter pump which receives fuel from the low pressure source and delivers the fuel at a second high pressure. The augmenter pump has a servo-controller to vary its pump flow rate. The system includes an augmentation valve which is actuatable by an electrically operated control valve to open a flow path therethrough which diverts fuel delivered by the augmenter pump or to shut the flow path. The system includes a pressure drop control valve which senses a pressure differential between the second high pressure and a reference pressure, and controls the servo-controller to vary the pump flow rate of the augmenter pump. The pressure drop control valve spills some of the fuel delivered by the augmenter pump.

A hydraulic transaxle comprises an axial piston hydraulic pump having a variable displacement, and a transaxle casing incorporating the hydraulic pump. The hydraulic pump includes a movable swash plate and a pair of trunnion shafts. The transaxle casing includes a pair of side walls, and includes a pair of casing holes each of which penetrates each of the side walls between an inside and an outside of the transaxle casing. The pair of trunnion shafts are passed through the respective casing holes. The swash plate is formed with a pair of swash plate holes in the respective side portions facing the respective side walls in the inside of the transaxle casing. Proximal end portions of the respective trunnion shafts are inserted into the respective swash plate holes. A distal end portion of one of the trunnion shafts projects from the corresponding casing hole to the outside of the transaxle casing.

A swash plate type variable displacement compressor includes, a housing, a swash plate disposed in the housing and having therethrough an insertion hole, a rotary shaft inserted through the insertion hole of the swash plate, a plurality of pistons engaged with the swash plate, and a connecting member disposed between the rotary shaft and the swash plate and connecting the rotary shaft and the swash plate so as to change inclination angle of the swash plate relative to the rotary shaft. A pair of projections are provided in the insertion hole so as to extend toward the rotary shaft and restrict the movement of the swash plate relative to the rotary shaft. The paired projections are spaced away from each other so as not to be in contact with the rotary shaft simultaneously.

A swash-plate type piston pump includes a cylinder block configured to be rotated with rotation of a driving shaft, a plurality of pistons accommodated in a plurality of cylinders provided in the cylinder block, a swash plate configured to reciprocate the piston so that a volume chamber of the cylinder is expanded/contracted with the rotation of the cylinder block, an biasing mechanism configured to bias the swash plate in a direction where a tilting angle is made larger, a control pin configured to drive the swash plate in a direction where the tilting angle is made smaller in accordance with a rise in a load pressure of a pressure chamber, and a discharge channel configured to discharge the load pressure of the pressure chamber.

Control systems and feedback assemblies for hydraulic axial displacement machines, such as pumps and motors. The control systems and feedback assemblies can reduce friction on the charging spools and provide for a more reliable return of the swashplate to a neutral position. Aspects of the control systems and feedback assemblies can be modularized for, e.g., easy maintenance and to reduce the overall size of the system.

An electro-hydraulic piston pump system comprising an electric motor (16), first and second hydraulic piston pumps (30,60), a first hydraulic actuator (90) having a first port (93) connected directly to a first port (48) of the first pump and a second port (94) connected directly to a second port (49) of the first pump, a second hydraulic actuator (100) having a third port (103) connected directly to a third port (78) of the second pump and a fourth port (104) connected directly to a fourth port (79) of the second piston pump, wherein an external force applied to the first hydraulic actuator (90) that provides a negative pressure differential to the first pump applies an assistive torque to a common motor shaft (18) driving both the first pump (30) and the second pump (60), and an external force applied to the first and second actuators (90,100) that provides a summed negative pressure differential to the first and second pumps (30,60) recharges a power supply for the motor (16).

A swash-plate type piston pump includes a cylinder block configured to be rotated with rotation of a driving shaft, a plurality of pistons accommodated in a plurality of cylinders provided in the cylinder block, a swash plate configured to reciprocate the piston so that a volume chamber of the cylinder is expanded/contracted with the rotation of the cylinder block, an biasing mechanism configured to bias the swash plate in a direction where a tilting angle is made larger, a control pin configured to drive the swash plate in a direction where the tilting angle is made smaller in accordance with a rise in a load pressure of a pressure chamber, and a discharge channel configured to discharge the load pressure of the pressure chamber.