A rotary positive displacement pump for fluids, in particular for the lubrication oil of a motor vehicle engine (60), has a displacement that can be regulated by means of the rotation of a stator ring (12) having an eccentric cavity (13) in which the rotor (15) of the pump (1) rotates. The stator ring (12) is configured as a multistage rotary piston for displacement regulation and is arranged to be directly driven by a fluid under pressure, in particular oil taken from a delivery side (19) of the pump or from a point of the lubrication circuit located downstream the oil filter (62). The invention also concerns a method of regulating the displacement of the pump (1) and a lubrication system for a motor vehicle engine in which the pump (1) is used.

A pendulum pump includes a housing, a cover positioned on the housing and forming a cavity therebetween, an inner rotor and an outer rotor positioned within the cavity, wherein the inner rotor is connected via a plurality of pendulums to the outer rotor, and the pendulums are mounted to the outer rotor in an articulated manner such that a rotational eccentricity can be imparted between the inner rotor and the outer rotor to control a flow rate of the pendulum pump, and a protective plate positioned within the cavity and against a surface of one of the housing and the cover.

A vane pump for providing a pressurized lubricant includes a static pump housing defining an inlet and an outlet, a shiftable control ring with at least one slide support surface, a pump rotor with rotor vanes which rotate within the control ring, and metal slide support pad(s). The control ring shifts with respect to the pump rotor to vary an eccentricity and to thereby control a volumetric pump performance. The pump housing comprises a static control ring housing body which radially surrounds and supports the control ring, and two static pump housing lids which axially support the control ring housing body and the control ring. The control ring housing body is made of plastic. The metal slide support pad(s) is fixed to the static control ring housing body and, together with the at least one slide support surface, provides a friction bearing for the control ring.

An automotive liquid pendulum vane pump includes a pump housing, a rotor ring with circular undercut recesses, a rotor hub with vane slots, and pendulum vanes which connect the rotor ring and the rotor hub. Each vane slot has a substantially plane contact wall slot with a tangential contact nose in an opening region and a diving recess. Each pendulum vane has a circular pendulum head which defines a pendulum hinge which corresponds to a circular undercut recess, a circular pendulum foot which is radially shiftable and pivotable in a vane slot, a vane leg which connects the circular pendulum head and the circular pendulum foot, and a contact path with a contact path surface which contacts the tangential contact nose in a rotational contact sector. A radial inner end of the contact path surface defines an inner tangential projection which temporarily dives into the diving recess.

This disclosure generally relates to an automatic bicycle, particularly to a hydraulic automatic transmission bicycle which can automatically and adaptively change gear ratios. More particularly, this disclosure relates to those hydraulic automatic transmission bicycles which use fluid pressure to change such gear ratios, and which include various hydraulic automatic transmissions which may be provided in various configurations and may operate in various methods and sequences to provide automatic and infinitely variable gear ratios.

A pendulum pump includes a housing, a cover positioned on the housing and forming a cavity therebetween, an inner rotor and an outer rotor positioned within the cavity, wherein the inner rotor is connected via a plurality of pendulums to the outer rotor, and the pendulums are mounted to the outer rotor in an articulated manner such that a rotational eccentricity can be imparted between the inner rotor and the outer rotor to control a flow rate of the pendulum pump, and a protective plate positioned within the cavity and against a surface of one of the housing and the cover.

Variable displacement pump has first control hydraulic chamber 21 giving force to cam ring 5 in direction that decreases volume variation of each pump chamber 13 by internal pressure, second control hydraulic chamber 22 giving force to cam ring in direction that increases volume variation of each pump chamber by internal pressure, first seal surface 44 formed on both end surfaces of cam ring, which are in sliding-contact with both opposing inside surfaces of pump body 1 and cover member 2, and sealing gap between each pump chamber and first control hydraulic chamber, and second seal surface 45 sealing gap between each pump chamber and second control hydraulic chamber at outlet section side. Radial direction width W2 of second seal surface is greater than that W1 of first seal surface. Increase in weight of the pump can be suppressed while suppressing increase in pump control pressure against intention of control.

Provided is a variable capacity pump where ease of control can be improved. A variable capacity pump includes a control chamber and a control mechanism. The control chamber is disposed between a pump accommodating chamber and a movable member, and the volume of the control chamber is variable with the movement of the movable member. Working oil discharged from a discharge portion is introduced into the control chamber. The control mechanism includes a spool, a biasing member, and a solenoid. The spool is provided in a passage, and is configured to control introduction of working oil into the control chamber by moving in a cylindrical portion. The spool is biased to one side in an axial direction by a pressure of working oil introduced into the cylindrical portion from the discharge portion. The biasing member biases the spool to an opposite side in the axial direction. The solenoid is configured to generate an electromagnetic force for biasing the spool in the axial direction, and to change a magnitude of the electromagnetic force according to a value of an electric current supplied.

A cam ring is capable of moving while rolling on a cam support surface. The cam ring is provided such that within a range in which the cam ring can move on the cam support surface, an eccentricity amount increasing-side angle is always greater than an eccentricity amount decreasing-side angle. On a plane perpendicular to the rotation axis of a driving shaft, the eccentricity amount increasing-side angle is an angle, in a direction opposite to a rotation direction of the driving shaft, from a first reference line, which connects a tangent point between the cam ring and the cam support surface to a rolling center of the cam ring, to a starting end of a first discharge port. The eccentricity amount decreasing-side angle is an angle, in the rotation direction of the drive shaft, from the first reference line to a terminal end of the first discharge port.

A pendulum pump includes a housing, a cover positioned on the housing and forming a cavity therebetween, an inner rotor and an outer rotor positioned within the cavity, wherein the inner rotor is connected via a plurality of pendulums to the outer rotor, and the pendulums are mounted to the outer rotor in an articulated manner such that a rotational eccentricity can be imparted between the inner rotor and the outer rotor to control a flow rate of the pendulum pump, and a protective plate positioned within the cavity and against a surface of one of the housing and the cover.