A screw compressor of the present invention comprises: a housing having a compression chamber; male and female rotors provided in the compression chamber; a driving shaft for rotating the male and female rotors; and a seal cover across which the driving shaft is provided, and further includes: an oil chamber provided at the seal cover, and returning, to the compression chamber, oil having leaked into the driving shaft; and a breather for injecting external air into the oil chamber. Therefore, the breather is provided at the upper part of the oil chamber and an oil recovery line is provided at the lower part thereof so as to cause a pressure difference between the upper and lower parts of the oil chamber, such that the flow of the oil having leaked into the driving shaft is smoothly recovered in the oil recovery line.

An electric pump provided with a pump unit configured to discharge working oil by being rotationally driven by an electric motor includes: a drive shaft configured to transmit rotational driving force from the electric motor to a rotor of the pump unit; a rotation-detection shaft provided coaxially with the drive shaft, the rotation-detection shaft being configured to be rotated together with the rotor; and a rotation detector unit configured to detect rotation of the rotation-detection shaft. The rotation-detection shaft has: an engagement portion configured to engage with the rotor; and a detection-target portion facing the rotation detector unit, and an outer diameter of the detection-target portion is set so as to be larger than an outer diameter of the engagement portion.

An electric pump provided with a pump unit configured to discharge working oil by being rotationally driven by an electric motor includes: a drive shaft configured to transmit rotational driving force from the electric motor to a rotor of the pump unit; a rotation-detection shaft provided coaxially with the drive shaft, the rotation-detection shaft being configured to be rotated together with the rotor; and a rotation detector unit configured to detect rotation of the rotation-detection shaft. The rotation-detection shaft has: an engagement portion configured to engage with the rotor; and a detection-target portion facing the rotation detector unit, and an outer diameter of the detection-target portion is set so as to be larger than an outer diameter of the engagement portion.

A gear pump having a drive shaft and at least two gear wheel pairs which each include a drive gear wheel and a driven gear wheel. The two gear wheels of a gear wheel pair are in meshing engagement with one another, and the drive gear wheels are arranged on the drive shaft and in torque-transmissive engagement with the drive shaft. The gear pump has a freely rotatably mounted shaft on which the driven gear wheels of the gear wheel pair are arranged in torque-transmissive engagement, wherein the driven gear wheels are mounted on the freely rotatably mounted shaft by means of a clearance fit.

The invention relates to a screw pump (1), in particular a double screw pump, s comprising a multiple-piece housing (2, 7, 15, 21) and at least two coupled rotors (3, 3a) which form chambers with in each case at least one thread-shaped profile (4, 4a) which is configured at least in regions with helical channels (5, 5a) and with dividing walls (6, 6a) which delimit the channels (5, 5a), wherein the rotors (3, 3a) perform an opposed rotor rotation, and the dividing walls (6, 6a) engage into one another in a gearwheel-like manner, a running housing part (7), wherein the running housing part (7) encloses the rotors (3, 3a) without contact, wherein the rotors (3, 3a) form, with the running housing part (7), at least one conveying chamber (8, 8a) for the fluid to be conveyed, wherein the conveying chamber (8, 8a) migrates axially along the rotor axis (10, 10a) and conveys the fluid from a suction chamber (11) into a pressure chamber (12), a suction-side connector element (13) which is connected fluidically to the suction chamber (11), and a pressure-side connector element (14) which is connected fluidically to the pressure chamber (12), wherein the suction-side connector element (13) and the pressure-side connector element (14) are arranged on a connector housing part (15) of the multiple-piece housing (2, 7, 15, 21), wherein the housing (2, 7, 15, 21) has a planar dividing plane (16) which runs parallel to the rotor axes (10, 10a) between the running housing part (7) and the connector housing part (15).

A board surface of a control board is disposed on an outward side of a motor in a radial direction in a posture along an axial direction. A rotation angle sensor is disposed on a rear side of a control board in the axial direction. A power supply input portion on the control board is disposed in an end portion on the rear side in the axial direction. A main body of a motor includes the control board and a wiring assembly electrically connecting a connector and the rotation angle sensor to each other. The wiring assembly includes a power supply input wiring, a sensor wiring, and a wiring holder holding the power supply input wiring and the sensor wiring.

A pump for applying fluid, the pump including: a pump housing, including: a fluid inlet on a low-pressure side; an fluid outlet on a high-pressure side; a circumferential wall surrounding the pump delivery chamber; and an end-facing wall featuring an outer end-facing surface facing axially away from the delivery chamber and at which the outlet emerges; a delivery member, moveable in the delivery chamber, for delivering the fluid from the low-pressure side to the high-pressure side; a gasket including a gasket loop which surrounds the outlet to seal it off on the outer end-facing surface of the end-facing wall; a female joining element featuring an axially extending hollow space; and a male joining element protruding through or from the pump housing or the gasket. The male joining element is in a joining engagement, which can be subjected to axial tensile stress, with the female joining element in the hollow space.

An eccentric screw pump with a rotor (2) and with a rotationally fixed stator (6; 6′) surrounding the rotor (2). The rotationally fixed stator includes at least one elastomeric portion, wherein a pressure chamber (16) is arranged on this elastomeric portion of the stator (6; 6′) at a side facing away from the rotor (2). The pressure chamber (16) is connected to a pressure region of the eccentric screw pump such that the at least one elastomeric portion of the stator (6; 6′) is subjected to a pressure produced by the eccentric screw pump.

An eccentric screw pump with a rotor (2) and with a rotationally fixed stator (6; 6′) surrounding the rotor (2). The rotationally fixed stator includes at least one elastomeric portion, wherein a pressure chamber (16) is arranged on this elastomeric portion of the stator (6; 6′) at a side facing away from the rotor (2). The pressure chamber (16) is connected to a pressure region of the eccentric screw pump such that the at least one elastomeric portion of the stator (6; 6′) is subjected to a pressure produced by the eccentric screw pump.

A crosslinked fluororesin-coated pump rotor manufacturing method is a method for manufacturing a pump rotor having flat rotor side surfaces and provided with a coating layer of a crosslinked fluororesin on each rotor side surface, the method including: screen-printing a dispersion liquid obtained by dispersing particles of a fluororesin in a solvent, on the rotor side surface by using a screen plate having an opening having a shape in which the opening does not protrude from an outer peripheral edge of the rotor side surface; then heating the pump rotor to a temperature equal to or higher than a melting point of the fluororesin to bake the fluororesin on the rotor side surface; and then irradiating the fluororesin with radiation to crosslink the fluororesin.