A mechanical lubricant pump includes a control ring which shifts between a maximum and a minimum eccentricity position, the control ring having a circumference with anti-spring and pro-spring hydraulic surfaces, a pump rotor having slidable vanes which rotate in the control ring, a preload spring which pushes the control ring into the maximum eccentricity position, a hydraulic pilot chamber which pushes the control ring into the minimum eccentricity position, a hydraulic pressure control circuit which controls a gallery pressure by regulating a pilot chamber pressure, and a hydraulic outlet chamber which surrounds a part of the circumference. The hydraulic pilot chamber is charged with a pump outlet pressure or with the gallery pressure of an engine. The hydraulic outlet chamber is charged with the pump outlet pressure and is connected to the pump outlet for a pressurized lubricant. The anti-spring hydraulic surface is larger than the counter-acting pro-spring hydraulic surface.

A vane pump has a housing defining a closed conduit fluidly coupling a discharge port and a planar surface, and an inner rotor eccentrically supported within a cam. The rotor has an outer perimeter defined by wall sections separated by axial slots. The rotor defines another closed conduit extending from one of the wall sections to a rotor end face that is configured to overlap with the closed conduit

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.

Provided is a variable capacity pump where ease of control can be improved. A variable capacity pump includes a control chamber and a control valve. 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 valve is provided in a passage and, with the movement of a valve element, the control valve varies the cross-sectional area of a flow passage, through which working oil in the control chamber is drained to a low pressure portion, while making the discharge portion and the control chamber communicate with each other.

A variable displacement oil pump includes an adjustable member that is configured to shift according to changes in pressure inside a control oil chamber. The adjustable member has a long hole. A guide pin is disposed inside the long hole. The guide pin is fixed to either a housing or a cover of the variable displacement oil pump. The width of the long hole is larger at a part of the long hole farther away from a fixed end of the guide pin in its lengthwise direction than at a part thereof closer to the fixed end.

A hydraulic conveying device for an internal combustion engine may include a pendulum slide pump including an inner rotor drivingly connected to an outer rotor via a plurality of pendulum slides. A hydraulic actuation device may change an eccentricity between the inner rotor and the outer rotor via an actuation member. The actuation member may be prestressed by a spring device. The actuation device may further include a first pressure-setting chamber and a second pressure-setting chamber for adjusting the actuation member. At least one of the first pressure-setting chamber and the second pressure-setting chamber may be connected via a control valve to a pressure side of the pendulum slide pump. A hydraulic line may connect the pendulum slide cell pump downstream to a hydraulic medium filter. The control valve may be connected to the hydraulic line upstream of the hydraulic medium filter.

A two-stage variable-displacement oil pump includes a casing having a suction port for suctioning oil stored in an oil tank and a discharge port for discharging, to a main gallery; an outer cam ring rotatably installed with respect to a pivot shaft provided inside the casing and having a rotary chamber therein; a rotor installed to be eccentric relative to the outer cam ring, rotating in concert with a rotation of a driving shaft, and including a plurality of vanes radially and slidably installed on an outer circumferential surface of the rotor; a support spring having one end contacting a spring support part formed on an outer side surface of the cam ring and the other end contacting an inner side surface of the casing; and a regulating chamber provided between the outer cam ring and the casing.

A variable lubricant vane pump which provides a pressurized lubricant for an engine includes a pump housing comprising a pump chamber. The pump chamber comprises pump compartments which rotate from a charge zone to a discharge zone. The pressurized lubricant is discharged from the pump compartments into an outlet cavity. A control ring envelopes the pump chamber and shifts between high and a low pumping volume position. A pump rotor comprises radially slidable vanes which rotate in the control ring. A pressure control chamber pushes the control ring into the high pumping volume direction. A control valve connects or disconnects the pressure control chamber to a lubricant tank. A pilot chamber pushes the control ring into the low pumping volume direction. A pilot chamber channel connects the outlet cavity with the pilot chamber. A control chamber channel connects the outlet cavity with the pressure control chamber.

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 vane fluid pump for a vehicle component has an inner rotor supported within a cam ring. A series of vanes is positioned within a series of slots in an inner rotor to define and separate a series of non-uniformly sized segmented pumping chambers to disrupt harmonics during operation to reduce pressure ripples and associated tonal noise. One chamber has a first sector angle being within a first predetermined range of a nominal value. A portion of the chambers each has a sector angle greater than the first sector angle, with an average sector angle greater than the nominal value by a second predetermined range. A remaining portion of the chambers each has a sector angle less than the first sector angle, with an average sector angle less than the nominal value by the second predetermined range.