A vane oil pump includes a rotor including a plurality of slits, a housing having an inner circumferential cam surface such that a first pump unit and a second pump unit taking in and discharging oil in accordance with rotation of the rotor are separately disposed in a rotational direction of the rotor, a plurality of vanes respectively fitted in the slits of the rotor, and a pressure adjusting device configured to adjust a second discharge pressure of the second pump unit to a lower pressure than a first discharge pressure of the first pump unit. A back pressure groove is disposed on the housing and is provided to supply back pressure oil to a bottom portion of each slit.

A gear pump that is used to pump fluid, such as oil, in a vehicle. The gear pump comprises a gear assembly having a drive shaft including a drive shaft key; a set of drive gears mounted on the drive shaft, with a drive gear of the set of drive gears being keyed with the drive shaft key; a driven shaft including a driven shaft key; a set of driven gears mounted on the driven shaft, with a driven gear of the driven gear set being keyed with the driven shaft key; and a torque drive feature associated with the drive shaft or the driven shaft, wherein the torque drive feature is configured to check keying with the driven shaft key.

Mobile means of transport (100) with a pump apparatus (1) and mobile pump apparatus (1) for use in mobile means of transport (100) such as semitrailers, tank trailers, tank semitrailers (101), tank trucks and trucks (102), comprising a drive motor (40) and a rotary piston pump (2). The drive motor (40) comprises a motor shaft (41) for driving the rotary piston pump (2). The rotary piston pump (2) comprises a housing (3) and two pump openings (4, 5) configured thereon, one of which serves as a pump inlet (4) and the other, as a pump outlet (5).

The rotary piston pump (2) comprises at least two rotor units (10, 20) rotatably accommodated in the housing (3) in a pump chamber (6) for conveying a fluid from the pump inlet (4) to the pump outlet (5). The two rotor units (10, 20) are accommodated on rotatably mounted rotor shafts (11, 21), each rotor shaft (11, 21) being equipped with a rotor gear wheel (12, 22) arranged outside the pump chamber (6). A drive pinion (32) of a drive shaft (31) of the rotary piston pump (2) is coupled to one of the rotor gear wheels (12). The motor shaft (41) of the drive motor (40) has a recess (81) at its front end (41a), where the drive shaft (31) of the rotary piston pump (2) is accommodated and coupled to the drive shaft (31).

A water pump for a marine engine includes a cap covering an internal cavity of the pump's housing when the pump is operating. The cap functions as a tool to remove a damaged or worn impeller from inside the internal cavity. A threaded hub of the cap engages internal threads of the impeller to assist a user in removing the impeller for replacement. A cap lock ring threaded onto the pump housing retains the cap over the internal cavity. A rotatable drive shaft has splines which mate with a splined portion of the impeller to rotate the impeller. The cap lock ring is disengaged from the housing and the cap removed to enable a person to use the threaded hub of the cap to remove the impeller.

The present disclosure provides a device for power transmission and signal transfer between the stator and the rotor of a screw drilling tool. The present disclosure can replace the wireless communication technique between the rotary steering tool and the integrated MWD/LWD, omit the upper mud generator above the rotary steering tool, and thereby realize power transmission and signal transfer between the stator and the rotor of the screw drilling tool.

A compressor includes: a driving unit including a stator, a rotor, and a rotary shaft provided in the rotor, having an oil guide path formed at an inner side in a radius direction; a compression unit coupled to the rotary shaft, having a cylinder and a piston reciprocating in the cylinder by a driving force of the driving unit; and an oil supply unit coupled to a lower end of the rotary shaft, supplying oil toward the compression unit. The oil supply unit includes a rotary portion for supplying oil toward the oil guide path while being rotated together with the rotary shaft and a fixed portion having an inner space partitioned to accommodate at least a portion of the rotary portion, and the oil guide path is formed to pass through the rotary shaft along a length direction.

A pump-motor combination includes a motor (30) and a pump (20). The pump has a first rotor (21) and a first housing 300). The motor is an electric motor (30) having a second rotor (31), a stator (33) and a second housing (32). The first (pump) rotor (21) is at least partially coupled, and the second (motor) rotor (31) is completely coupled, to a common rotating shaft (40) in order to enable transmission of rotation of the second (motor) rotor (31) to the first (pump) rotor (21). The pump-motor combination can be installed with the gearbox (G) or transmission of a motor vehicle, to assure supply of lubricant (360) when a primary lubricant pump (350) has not been operating, for example, upon start-up. Use of the common shaft (40) minimizes frictional losses during operation and reduces the cost of manufacture, since fewer bearings are needed.

A method for fixing rotary pistons in a rotary piston pump and a method for dismantling rotary pistons of a rotary piston pump, where the rotary piston pump has two counter-rotating rotary arranged in a pump space on drive shafts. The rotary pistons each include a seating for the drive shafts. The respective drive shaft is arranged and fixed with an end region in the seating of the respective rotary piston. A diameter of the drive shafts in the end region can be widened elastically. In an operational state, in which the rotary pistons are arranged on the respective drive shafts, a frictional connection is formed between the respective seating of the rotary piston and the end region of the respective drive shaft.

The present disclosure provides a device for power transmission and signal transfer between the stator and the rotor of a screw drilling tool. The present disclosure can replace the wireless communication technique between the rotary steering tool and the integrated MWD/LWD, omit the upper mud generator above the rotary steering tool, and thereby realize power transmission and signal transfer between the stator and the rotor of the screw drilling tool.

A mounting hub operable to connect a flexible impeller to a drive shaft. The mounting hub is detachable from the impeller, and is adapted to permit the impeller to be decoupled rotationally from the impeller drive shaft during installation, and then recoupled rotationally once the flexible impeller is in position.