Gear pump

About: Gear pump is a(n) research topic. Over the lifetime, 7490 publication(s) have been published within this topic receiving 38837 citation(s). The topic is also known as: Gear pump.

Rotary hydraulic pump actuated multi-stroke surgical instrument

Abstract: A surgical instrument (e.g., endocutter, grasper, cutter, staplers, clip applier, access device, drug/gene therapy delivery device, and energy device using ultrasound, RF, laser, etc.) may benefit from having a plurality of hydraulically actuated subsystems (e.g., severing, stapling, articulation, locking/unlocking, lockout enabling/disabling, grasping, etc.) supplied with hydraulic power from a trigger actuated rotary pump (e.g., lobe pump, rotary gear pump, internal rotating gear pump, flexible vane rotor pump, rotary vane pump). Thereby, an available amount of mechanical advantage available at a firing trigger may be optimally distributed to various end effector components, perhaps sequenced by an electroactive polymer or piezoelelectrically actuated function switch block.

Surgical stapling instruments structured for delivery of medical agents

Abstract: A medical agent dispensing system can be provided that may be structured for use with a surgical severing/stapling instrument that is designed for severing and stapling tissue. The dispensing system may include at least one storage reservoir structured for storing at least a component of a medical agent; a gear pump casing in communication with the storage reservoir; a screw pump auger positioned within the gear pump casing capable of rotational manipulation to move the medical agent through the gear pump casing; and, at least one agent tube in communication with the gear pump casing. The agent tube may be structured for communication with a least one agent port formed in a staple cartridge of the surgical instrument for dispensing the medical agent therethrough.

Hydraulic hybrid vehicle

Abstract: An automotive powertrain includes a hydraulic drive circuit including at least one of: a hydraulic pump/motor (12) having a shaft fixed to for rotation with the crankshaft of an internal combustion engine (11); and a pair of pump/motors (21, 22) coaxially arranged to share a common shaft on which is mounted a gear of a gear set for transmitting output to the vehicle drive wheels (20). Hydraulic control logics are provided for control of the various pump/motors of the hybrid powertrain.

Hydraulic control systems

Abstract: Preface. Introduction. I. FUNDAMENTALS. 1 Fluid Properties. 1.1 Introduction. 1.2 Fluid Mass Density. 1.3 Fluid Bulk Modulus. 1.4 Thermal Fluid Properties. 1.5 Fluid Viscosity. 1.6 Vapor Pressure. 1.7 Chemical Properties. 1.8 Fluid Types and Selection. 1.9 Conclusion. 1.10 References. 1.11 Homework Problems. 2 Fluid Mechanics. 2.1 Introduction. 2.2 Governing Equations. 2.3 Fluid Flow. 2.4 Pressure Losses. 2.5 Pressure Transients. 2.6 Hydraulic Energy and Power. 2.7 Lubrication Theory. 2.8 Conclusion. 2.9 References. 2.10 Homework Problems. 3 Dynamic Systems and Controls. 3.1 Introduction. 3.2 Modeling. 3.3 Linearization. 3.4 Dynamic Behavior. 3.5 State-Space Analysis. 3.6 Block Diagrams and the Laplace Transform. 3.7 Stability. 3.8 Compensation. 3.9 Conclusion. 3.10 References. 3.11 Homework Problems. II HYDRAULIC COMPONENTS. 4 Hydraulic Control Valves. 4.1 Introduction. 4.2 Valve Flow Coefficients. 4.3 Two-Way Spool Valves. 4.4 Three-Way Spool Valves. 4.5 Four-Way Spool Valves. 4.6 Poppet Valves. 4.7 Flapper Nozzle Valves. 4.8 Conclusion. 4.9 References. 4.10 Homework Problems. 5 Hydraulic Pumps. 5.1 Introduction. 5.2 Pump Efficiency. 5.3 Gear Pumps. 5.4 Axial-Piston Swash-Plate Pumps. 5.5 Conclusion. 5.6 References. 5.7 Homework Problems. 6 Hydraulic Actuators. 6.1 Introduction. 6.2 Actuator Types. 6.3 Linear Actuators. 6.4 Rotary Actuators. 6.5 Conclusion. 6.6 References. 6.7 Homework Problems. III HYDRAULIC CONTROL SYSTEMS. 7 Valve-Controlled Hydraulic Systems. 7.1 Introduction. 7.2 Four-Way Valve Control of a Linear Actuator. 7.3 Three-Way Valve Control of a Linear Actuator. 7.4 Four-Way Valve Control of a Rotary Actuator. 7.5 Conclusion. 7.6 References. 7.7 Homework Problems. 8 Pump-Controlled Hydraulic Systems. 8.1 Introduction. 8.2 Fixed-Displacement Pump Control of a Linear Actuator. 8.3 Variable-Displacement Pump Control of a Rotary Actuator. 8.4 Conclusion. 8.5 References. 8.6 Homework Problems. INDEX.

The Theoretical Flow Ripple of an External Gear Pump

Abstract: In this paper, the theoretical flow ripple of an external gear pump is studied for pumps of similar size using different numbers of teeth on the driving and driven gears. In this work, the flow ripple equation is derived based upon the flow of incompressible fluid across the changing boundaries of a control volume. From this method, it is shown that the instantaneous length of action within the gear mesh determines the instantaneous flow ripple. A numerical and a closed-form approximation are presented for the instantaneous length of action and it is shown that the difference between these two solutions is negligible. Fast Fourier transform analysis is employed for identifying the harmonic frequencies and amplitudes of the flow pulse and these results are compared for 16 different pump designs. In summary, the results of this study show that the driving gear dictates the flow ripple characteristics of the pump while the driven gear dictates the pump size. As a result, it may be advantageous to design an external gear pump with a large number of teeth on the driving gear and a fewer number of teeth on the driven gear This design configuration will tend to reduce both the physical pump size (without reducing the volumetric displacement of the pump) and the amplitude of the flow pulsation, while increasing the natural harmonic frequencies of the machine.