Systems and methods for providing a dynamically adjustable reciprocating fluid dispenser

Inventors

Peeler, Scott C. • Guest, Brian W.

Assignees

Zaxis Inc

Abstract

Systems and methods for providing a dynamically adjustable, synchronously and/or asynchronously reciprocating fluid dispenser. A pump drive motor is coupled to the reciprocating fluid pump to actuate a pump shaft within a pump cylinder, wherein the pump shaft includes a duct that allows fluid to selectively pass thereby within the pump cylinder. As the pump shaft rotates within the pump cylinder, fluid is allowed to enter into a pump bore defined by a portion of the pump cylinder through a pump ingress port. As the pump shaft rotates, it blocks the pump ingress port. Further rotation allows the duct to allow the fluid in the pump bore to be dispensed through a pump egress port. An adjustment motor is coupled to an adjustment mechanism, which selectively adjusts the volume of the pump bore. A controller is coupled to the adjustment motor to dynamically control the adjustment motor, to cause the adjustment mechanism to be precisely and repeatably modified, and/or to control the particular waveform. As such, the volume of fluid dispensed is extremely accurate, repeatable, and dynamic.

Core Innovation

The invention describes a dynamically adjustable valveless reciprocating fluid dispensing system configured to selectively dispense a precise and repeatable volume of fluid. The system uses a reciprocating fluid pump having a pump shaft and a pump cylinder, and a pump drive motor coupled to the pump to selectively actuate the pump shaft within the pump cylinder. A pump-shaft duct with pump ingress and pump egress ports meters fluid volume between a fluid source and a dispense target.

The system includes an electrical adjustment mechanism coupled to the reciprocating fluid pump to precisely and repeatably adjust the stroke of the pump shaft. The electrical adjustment mechanism dynamically and repeatably changes the pump bore or pump stroke under controller control, enabling selectable/specified waveform control such as synchronous and/or asynchronous operation. Mechanical embodiments described include changing shaft angle with gear systems, linear actuator and screw arrangements, and pivot or hinge-block arrangements coupled to a cam follower.

The patent further describes mechanical structures configured to address clearance and repeatability, including embodiments using compensation spring bias to compensate for clearance and backlash between components such as a cam follower bearing surface and a hinge-block race. Additional embodiments include gear-based synchronous reciprocation, micro-stepping motor adjustment, non-captive and captive screw arrangements, and multi-piston phase offset to reduce pulsing. Example arrangements are implemented with controller control and may include sensors such as linear travel sensors.

Overall, the core innovation is the combination of a precisely metered reciprocating valveless dispenser path using pump ingress and egress ports, with a controller-driven electrical adjustment mechanism that precisely and repeatably modifies the pump shaft stroke and enables selectable waveform dispensing.

Claims Coverage

The provided independent claims are clm-00001 and clm-00011. Both claims cover a reciprocating fluid dispensing system that selectively dispenses a precise and repeatable fluid volume by combining a motor-driven reciprocating pump with an electrical adjustment mechanism that precisely and repeatably adjusts the pump shaft stroke, using a linear actuator, screw, slide, cam follower, and a hinge block with a race.

In the claim scope provided, both independent claims concentrate on precise and repeatable dispensing of a fluid volume using a reciprocating pump whose stroke is precisely and repeatably adjusted by an electrical adjustment mechanism. The main structural inventive features relate to the specific coupling of a linear actuator and screw to a slide with a sleeve element, a cam follower, and a hinge block race to support repeatable stroke adjustment.

Stated Advantages

Documented Applications