Vane pump for pumping hydraulic fluid
AssigneeMathers Hudraulics Pty. Ltd.
InventorNorman Ian Mathers
Life of this patent
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Abstract
A vane pump of the intravane type for pumping hydraulic fluid, wherein each vane of the pump has two intravanes and that pressurized oil is provided to one or both intravane regions when the vane is in a rise region of the pump. The pump is operated such that the pressurized oil is provided to both undervane regions when the pump is running at low speed but the pressurized oil is provided to only one of the undervane regions when of the pump is running at high speed.
Claims12
A vane pump for pumping hydraulic fluid comprising:
- a body having a chamber;
- and a rotor rotatable within the chamber, the chamber and the rotor being shaped to define one or more rise, fall and dwell regions between walls of the chamber and the rotor, the rotor having a plurality of slots, a plurality of vanes, with each slot of the rotor having a vane of the plurality of vanes located therein, each vane being moveable between a retracted position and an extended position˜ with each vane having two intravanes disposed therein, wherein in the retracted position the vanes do not work the hydraulic fluid and in the extended position the vanes work the hydraulic fluid, wherein the chamber defines one or more inlets for introducing relatively low pressure hydraulic fluid, at an inlet pressure, into the one or more rise regions, and wherein the chamber defines one or more outlets for discharging relatively high pressure hydraulic fluid, at an outlet pressure, from the one or more fall regions, wherein the rotor defines an under vane passage extending beneath each vane with the vane resisting fluid flow between the under vane passage and the chamber through the vane, and a plurality of flow passages, each to communicate pressurized hydraulic fluid to a portion of an under vane passage, wherein each vane has disposed therein at least two intravanes located below an upper surface of the vane, and the rotor defines respective flow passages of the plurality of flow passages, each in fluid communication with a respective under vane passage to communicate pressurized hydraulic fluid to the intravanes, wherein in a first mode of operation pressurized hydraulic fluid is delivered to both intravanes regions of a vane when the pump is operating at a relatively low pump speed, and in a second mode of operation pressurized hydraulic fluid is delivered to one intravane of the vane when the pump is operating at a relatively high pump speed.
A vane pump for pumping hydraulic fluid comprising a body having a chamber and a rotor rotatable within the chamber, the chamber and the rotor being shaped to define one or more rise, fall and dwell regions between walls of the chamber and the rotor, the rotor having a plurality of slots, each slot of the rotor having a vane located therein, each vane being moveable between a retracted position and an extended position wherein in the retracted position the vanes do not work the hydraulic fluid and in the extended position the vanes work the hydraulic fluid, one or more inlets for introducing relatively low pressure hydraulic fluid into the one or more rise regions and one or more outlets for discharging relatively high pressure hydraulic fluid from the one or more fall regions, an under vane passage extending beneath each vane, at least one flow passage for supplying pressurized hydraulic fluid to the under vane passages, each vane having at least two regions located below an upper surface of the vane, and flow passages for delivering pressurized hydraulic fluid to one or more of the at least two regions, wherein pressurized hydraulic fluid is delivered to both regions of a vane when the pump is operating at relatively low pump speeds, but delivered to only one region of a vane when the pump is operating at relatively high pump speeds, the pump including a control valve that is directly responsive to pump speed to control a flow of hydraulic fluid, wherein the pump is provided with a speed sensor and the speed sensor is configured to send a signal to the control valve and the control valve is configured to be controlled by a control algorithm to switch the valve from allowing flow to both regions of a vane to allowing flow to one region of the vane when the speed sensor detects that the pump speed has passed a predetermined threshold value.
A method for operating a vane pump of the intravane type for pumping hydraulic fluid, wherein each vane has two intravanes, each intravane positioned in a respective intravane region on respective sides of the pump, which method comprises:
- providing pressurized hydraulic fluid to both of the two intravanes at low pump speeds;
- and providing pressurized hydraulic fluid to only one intravanes of the two intravanes at high pump speeds, wherein for each vane of the pump, hydraulic fluid is restricted from flowing between an under vane region and a chamber of the pump through the vane.
A system, comprising:
- a pump housing;
- a vane pump rotating group rotatably disposed in the pump housing, the vane pump rotating group including:
- a block;
- and a plurality of vanes, with each of the vanes including two intravanes, one on a first side of the pump, and a second on a second side of the pump, wherein the block defines respective passages extending to a bottom of each intravanes, with a first set of passages on the first side in fluid communication with one another, and a second set of passages on the second side in fluid communication with one another;
- and a valve to, in a first mode of operation, place the first set of passages in fluid communication with a hydraulic signal to raise intravanes on the first side of the pump, and to, in a second mode of operation, place the second set of passages in fluid communication with the hydraulic signal to raise intravanes on both sides of the pump.
Dependencies are inferred from the claim text.