A rotary pump is presented for use in a medicament delivery device, where the pump has a back plate having an inner surface and a rotor housing is positioned adjacent to the back plate having a peripheral wall. A front plate support is connected to the back plate and a flexible front plate is positioned between the front plate support and the rotor housing. The pump is rotated using a planetary gear transmission, where an eccentric shaft is operatively connected to the planetary gear mechanism. A rotor is rotationally fixed to the eccentric shaft and movably positioned within the rotor housing. The rotor has three lobes, where each lobe has two peripheral curved surfaces sharing a common apex, where a first portion of each peripheral surface adjacent to the apex defines a non-smooth curve.

A rotary pump is presented for use in a medicament delivery device, where the pump has a back plate having an inner surface and a rotor housing is positioned adjacent to the back plate having a peripheral wall. A front plate support is connected to the back plate and a flexible front plate is positioned between the front plate support and the rotor housing. The pump is rotated using a planetary gear transmission, where an eccentric shaft is operatively connected to the planetary gear mechanism. A rotor is rotationally fixed to the eccentric shaft and movably positioned within the rotor housing. The rotor has three lobes, where each lobe has two peripheral curved surfaces sharing a common apex, where a first portion of each peripheral surface adjacent to the apex defines a non-smooth curve.

A pump housing of an oil pump includes a suction port that supplies oil to a pump room, a discharge port that discharges oil from the pump room, and a seal portion that suppresses leakage of oil from the pump room to outside of the pump room. A shaft of the oil pump includes a small diameter portion and a large diameter portion having different diameters, the small diameter portion is connected to the inner rotor, and the shaft and the inner rotor integrally rotate. The seal portion is in contact with a side surface of the inner rotor extending in a diameter direction of the shaft, and also extends to a region in the diameter direction on an inner side smaller than the large diameter portion in the diameter direction.

A pump housing of an oil pump includes a suction port that supplies oil to a pump room, a discharge port that discharges oil from the pump room, and a seal portion that suppresses leakage of oil from the pump room to outside of the pump room. A shaft of the oil pump includes a small diameter portion and a large diameter portion having different diameters, the small diameter portion is connected to the inner rotor, and the shaft and the inner rotor integrally rotate. The seal portion is in contact with a side surface of the inner rotor extending in a diameter direction of the shaft, and also extends to a region in the diameter direction on an inner side smaller than the large diameter portion in the diameter direction.

Rotary positive displacement machines based on trochoidal geometry, that comprise a helical rotor that undergoes planetary motion within a helical stator are described. The rotor can have a hypotrochoidal cross-section, with the corresponding stator cavity profile being the outer envelope of the rotor as it undergoes planetary motion, or the stator cavity can have an epitrochoidal cross-section with the corresponding rotor profile being the inner envelope of the trochoid as it undergoes planetary motion. In some embodiments, the geometry is offset in a manner that provides structural and/or operational advantages in the rotary machine.

Rotary positive displacement machines based on trochoidal geometry, that comprise a helical rotor that undergoes planetary motion within a helical stator are described. The rotor can have a hypotrochoidal cross-section, with the corresponding stator cavity profile being the outer envelope of the rotor as it undergoes planetary motion, or the stator cavity can have an epitrochoidal cross-section with the corresponding rotor profile being the inner envelope of the trochoid as it undergoes planetary motion. In some embodiments, the geometry is offset in a manner that provides structural and/or operational advantages in the rotary machine.

The present disclosure describes a rotary pulsation generator having a simple structure capable of transferring fluid while implementing low noise and low vibration and having high flow of fluid and high pressure suction and discharge functions. According to the present disclosure, fluid is transferred by adjusting a width and interval of pulsation while reducing vibration caused by eccentric rotation of a rotor.

A pump body assembly, fluid machinery, and a heat exchange device. The pump body assembly includes: at least two structure members; a cylinder disposed between the two structure members; and a piston assembly disposed in the cylinder. The piston assembly includes a piston sleeve and a piston slidably disposed in the piston sleeve; an upper end surface of the piston sleeve fits and is limited by a lower end surface of one structure member disposed above the piston sleeve, to prevent the piston sleeve from displacing along a radial direction relative to the one structure member, and effectively solving a problem in prior art that working efficiency of the pump body assembly is affected because the piston sleeve of the pump body assembly is prone to eccentrically rotate.

A pump body assembly, fluid machinery, and a heat exchange device. The pump body assembly includes: at least two structure members; a cylinder disposed between the two structure members; and a piston assembly disposed in the cylinder. The piston assembly includes a piston sleeve and a piston slidably disposed in the piston sleeve; an upper end surface of the piston sleeve fits and is limited by a lower end surface of one structure member disposed above the piston sleeve, to prevent the piston sleeve from displacing along a radial direction relative to the one structure member, and effectively solving a problem in prior art that working efficiency of the pump body assembly is affected because the piston sleeve of the pump body assembly is prone to eccentrically rotate.

A device providing a dosed supply of a liquid includes: a pump configured to deliver the liquid and having a pump housing with an inlet and an outlet; an eccentric on the pump housing; and a deformable diaphragm between the pump housing and the eccentric, the deformable diaphragm and the pump housing delimiting a delivery path from the inlet to the outlet and forming a seal of the delivery path. The seal is displaceable along the delivery path, by a movement of the eccentric, in a delivery direction from the inlet to the outlet to deliver the liquid. The pump is configured such that within the pump a friction torque that must be overcome for the eccentric to move is greater than a maximum pressure torque that can be generated by pressurized liquid in the delivery path, so as to prevent movement of the eccentric counter to the delivery direction.