Translational displacement pump and bulk fluid re-supply system

Abstract

A novel method of designing a pump by utilizing a cylinder with pistons inserted from each end. The cylinder contains two ports along the top for connection of a prime fluid chamber, a bulk fluid supply chamber and a fluid reservoir. These ports and corresponding connection details are arranged in a fashion that is perpendicular to the axis of the cylinder that comprises the pump chamber. Directly below at a different relative position also perpendicular to the axis of the pump chamber is an exit port for extrusion of fluid. The pump contains no valves or ancillary passages to direct flow between the different machine states of prime, refill, translate and dispense. The states are activated by relative position of the pistons with respect to each port. Fluid moves by translation within the pump by filling the chamber volume between the two pistons with a liquid and synchronizing the advance of the left piston with the retreat of the right piston. Both pistons can be directed toward one another or one piston can remain stationary while the other advances toward it to dispense a liquid. Exceptionally accurate volumes of fluid can be deposited because of the absence of compliant members in the wetted path.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application is entitled to the benefit of Provisional Patent Application Ser. No. 60 / 860,172 filed Nov. 20, 2006.FEDERALLY FUNDED RESEARCH[0002]Not ApplicableSEQUENCE LISTING OR PROGRAM[0003]Not ApplicableBACKGROUND OF INVENTION[0004]1. Field of the Invention[0005]This invention pertains to the field of liquid dispensing equipment. More particularly, it pertains to design of a pump that employs a novel method of pumping or extruding a fluid. The pump design is capable of accomplishing this task without the use of valves or redirection of fluid through ancillary pathways. Both pistons occupy a circular cavity or tube; each piston is inserted from opposite ends, a reservoir and a prime chamber are installed on the topside of the tube. The exit port is directly below and provides for connection of a nozzle or other passage for extrusion of the fluid.[0006]2. Description of the Prior Art[0007]At present there are four general types of pu...

AI Technical Summary

Benefits of technology

[0028]15.) To provide a pump design that has the capacity to support formulation of a compressibility offset for fluids like sealants and silicones that have a high degree of elasticity and move sluggishly until compressed slightly.

[0029]The invention is a novel method of designing such a pump for delivering a measured quantity of viscous liquid or other liquids through a nozzle for deposit or connection to another passage for extrusion of the fluid. Fluid forced through the exit port of the pump enters a nozzle that directs it for deposit. A translational displacement pump comprises:

[0030]A hollow cylindrical chamber with a series of ports through the wall perpendicular to the longitudinal axis, enabling connection of a prime chamber, reservoir, a bulk supply of fluid and a nozzle. Two smaller diameter cylindrical bodies are inserted from each end of the hollow cylindrical chamber; they are slightly smaller than the inside diameter, of the hollow cylindrical chamber. A thin ring of compliant material at the end of each smaller diameter cylindrical body seals against the high pressure created from extrusion of fluid out the exit port, through the nozzle onto the work.

[0031]The conical shape of the interior of the thin ring of compliant material contains a concave cone made to an angle more obtuse than the angle of the cone and conjoined stem. Tensile force applied to the stem connected to the acutely angled cone that resides in the conical shape of the interior of the thin ring of compliant material energizes the compliant material, forcing the forward edge of the thin ring of compliant material outward, creating a surface capable of holding back high pressure. In operation, when pre

Problems solved by technology

Constrictive nozzle designs, a long fluid path combined with high viscosity liquids cause high pressures, when this occurs the pump leaks fluid from around the rotary seal of the stopcock.

Lack of a linear encoder means all measures of cylinder position are estimated and are not an absolute measure of position.

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