Gear pump

About: Gear pump is a research topic. Over the lifetime, 7490 publications have been published within this topic receiving 38837 citations. The topic is also known as: Gear pump.

Direct grease injection for large open gearing

Abstract: A drive gear includes a plurality of internal radial channels extending between the axial bore and the periphery of the gear, and an axial bore includes a lubricant distribution structure therein to provide lubrication where the teeth of the drive gear mesh with the teeth of a gear driven by the drive gear.

Limited slip differential having thermal compensating valve for regulating torque bias

Abstract: A limited slip differential for an automotive vehicle includes a torque input differential pinion carrier, two differential side gears and a pair of torque output axle half shafts. The differential also includes at least one friction clutch assembly having first friction clutch plates connected driveably to the differential pinion carrier and second friction clutch plates connected driveably to one of the side gears. An annular pressure chamber is defined in the carrier. An annular piston is movably supported within the pressure chamber and adjacent the friction plates of the friction clutch assembly. The limited slip differential further includes a positive displacement gear pump having pumping elements defining high pressure and low pressure ports whereby pressure in the pressure chamber creates a force on the piston that engages a clutch assembly to effect a friction torque bias in the differential through the friction clutch assembly. The piston includes at least one flow control orifice through which fluid may flow from the high pressure port of the positive displacement gear pump via the annular pressure chamber and a thermal compensating valve that is mounted on the piston and is operable to decrease the flow area of the flow control orifice upon increasing temperature. Furthermore, the thermal compensating valve is also operable to increase the flow area of the flow control orifice upon decreasing temperature.

A New Type of Hydraulic Actuator Using Electrorheological Fluids

Abstract: Electrorheological Fluids (ERF) are usually used in semi active damping elements, e.g. shock absorbers or engine mounts because of their continuously controllable shear stress. A totally new field of application may be achieved, if an ERF is used as a hydraulic fluid and not only as a control medium. In this case a fundamental need is the capability to produce a volume flow by using normal hydraulic pumps, e.g. gear pumps. The ERF and the hydraulic components both must have a long lifetime without unusual wear. Bayer AG has developed an ERF based on soft crosslinked PU-particles dispersed in silicone oil. These ERF are characterised by a low basic viscosity, a high ER-effect and a moderate conductivity. Compared with previous ERF where hard inorganic particles were used, the new fluid is not abrasive. It is foremostly this characteristic which gives the possibility of using the ERF in hydraulic systems with high shear rates and high shear stresses. The usage of ERF as hydraulic fluid allows the construction of proportional valves without mechanically driven parts. The control of the pressure drop over the valves is realised directly by an electrical signal. It is possible to realise actuators with very fast response times since the reaction time of ERF is within milliseconds. For demonstration purpose Bayer AG has built an actuator which is controlled by an electrorheological valve-block. The calculation of the dimension of this actuator and the valves will be shown and the realised response time will be demonstrated.