Tesma International Inc. Patent applications |
Patent application number | Title | Published |
20130089446 | Variable Capacity Vane Pump with Dual Control Chambers - A variable capacity vane includes a pump control ring which is moveable to alter the capacity of the pump and the pump can be operated at either of at least two selected equilibrium pressures. The pump ring is moved by at least first and second control chambers, the control chambers abutting the control ring such that pressurized fluid supplied to them acts on the pump control ring to move the pump control ring to reduce the volumetric capacity of the pump. When pressurized fluid is supplied to only one control chamber, the pump operates at a first equilibrium pressure and when pressurized fluid is also supplied to the second chamber, the pump operates at a second equilibrium pressure. Pressurized fluid can also be supplied only to the second control chamber to operate the pump at a third equilibrium pressure and/or additional control chambers can be provided if required. | 04-11-2013 |
20080247894 | Vane Pump Using Line Pressure to Directly Regulate Displacement - A variable displacement vane pump includes at least two regulation chambers to provide a regulating force to the cam ring, to counter the force applied to the cam ring by a regulating spring, to reduce pulsation in the output working fluid from the pump. A first one of the chambers is part of the pump outlet and is in fluid communication with the outlet port of the pump via a passage which allows the pump to be fabricated from a diecast process oath like. A second regulation chamber is connected to the first chamber via an orifice which reduces the pressure of working fluid supplied from the first chamber to the second. The configuration and design of pumps in accordance with the present invention allows for flexible packaging for the pump, as the outlet need not overlie the pump outlet. Further, a pump with an inlet port with a relatively large initial cross-sectional flow area is taught to inhibit cavitation of the working fluid when the pump is operated at higher operating speeds. | 10-09-2008 |