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.

Extrusion of polymers

Abstract: Processes and apparatus for melt extrusion of polymeric compositions, particularly conductive polymers, in which a gear pump (3) delivers molten polymeric composition to an extrusion orifice (41). Overfeeding of the composition due to pressure variations is avoided by means of a polymer relief means (5), preferably a second, smaller gear pump (5), which removes a portion of the molten composition when the pressure exceeds a selected level.

Gear pump bearings

Abstract: Variations in pump capacity of gear pumps due to varying leakage paths occurring in otherwise identical pumps as a result of the manufacturing operation are minimized without unduly hindering the fitting of the bearings through the pump housing by maintaining the distance "TBD" between the center of the bearing journal and the bearing flat closely within tolerances and by providing a relief in the bearing periphery diametrically opposite of the flat.

Variable displacement gear pump

Abstract: PROBLEM TO BE SOLVED: To provide a gear pump wherein the discharge capacity is made variable according to a load. SOLUTION: In a casing, a driving gear and two driven gears biting each other to the driving gear are accommodated, and a main body 10 (double gear pump) of gear pump which actuates as the first pump 21 and the 2nd pump 24 in the 2 pipe lines are formed. The discharge port 23 and suction port of the second gear pump 24 are connected by an unloading passage 28, and in the unloading passage 29, an on-off solenoid valve 29 is provided. In the case of closing an on-off solenoid valve 29, the 1st and the 2nd pump 21 and 24 become the parallel running, and discharge capacity becomes large. In the case of opening the solenoid valve 29, the discharge capacity becomes small, since the 2nd pump 24 is unloaded.

Mechatronic micro devices

Abstract: Nowadays, novel trends can be observed in micro system technology: Micro systems more and more develop into stand-alone devices for multi-purpose applications, and they do not only comprise detector elements but really interact mechanically by micro actuators with their surroundings. A modular concept especially for high performance actuators which proved to be a main prerequisite for these developments is illustrated in the contribution. With dimensions of a few millimeters, piezo-driven valves and membrane pumps overcome fluid pressures of 1,000 hPa. Electromagnetic motors generate torques of 7 to 100 /spl mu/Nm which are multiplied by adapted micro gears. Gear motors serve as a key unit for high force micro positioning systems or micro gear pumps which are first examples for the device level. With the integration of electronics and optics the actuator performance can considerably be increased by establishing a feedback control and the systems become really micro mechatronic devices. Additionally, interface components like electrical and fiber-optical connectors with pitches as small as 250 /spl mu/m, special gears and miniaturized clamping structures enable the implementation of complex optical fiber networks, micro robots or chemical micro reactors from these mechatronic devices in a construction kit. A wide range of 3D-micro fabrication techniques, from design and simulation, micro spark erosion (/spl mu/-EDM) for the prototypes to mass technologies like LIGA including injection molding, allows a fast commercialization into "micro product lines" and will round the circle of the considerations on the mechatronic micro devices.