Chamber valve

• US 6,036,166 A
• Filed: 09/25/1998
• Issued: 03/14/2000
• Est. Priority Date: 09/25/1997
• Status: Expired due to Fees

• Current Assignee: IMI Cornelius Incorporated (Berkshire Hathaway Incorporated)
• Original Assignee: IMI Cornelius Incorporated (Berkshire Hathaway Incorporated)
• Inventors: Olson, David L.
• Primary Examiner(s): Douglas, Steven O.
• Assistant Examiner(s): NGUYEN, TUAN N
• Application Number:
  US09/160,390
• Time in Patent Office: 536 Days
• Field of Search: 251/7, 239/119, 239/124, 222/109, 222/207, 222/214, 141/115, 141/116, 141/117
• US Class Current: 251/7
• CPC Class Codes: F16K 7/06 by means of a screw-spindle, cam, or other mechanical means F16K7/045 takes precedence

Abstract

A valve having a linear actuator operating a tube compression rod. The rod is held in a common axial orientation with a section of flexible tubing that runs through the valve and is rigidly held therein between the compression rod and a tube platen. The flexible tube section is fluidly connected on one end thereof to a pump that delivers a viscous material thereto from a source thereof. The opposite end of the flexible tube section is fluidly connected to a dispense point. In operation, the linear actuator is operable between an extended position wherein the compression rod moves to partially occlude or compress the flexible tube section against the tube platen, and a retracted position wherein the flexible tube section is not compressed. Dispensing of the viscous substance is commenced by actuation of a switch operating the pump. During operation of the pump, the chamber valve is in its extended position wherein the flexible tube section is partially occluded. When sufficient viscous substance has been dispensed, the pump is turned off. At the same time the chamber valve is operated to move to its retracted position. Such movement results in the flexible tube section moving to its non-occluded position whereby a suction force is applied to the viscous substance at the dispense point. As a result, a small volume of the viscous material is moved away from the dispense point in the reverse direction of its normal flow for preventing dripping thereof from the dispense point.

Claims

1. A chamber valve for use in a system for dispensing a viscous substance, the viscous substance being moved by a pump from a source thereof to a dispense point, the chamber valve, comprising:

a rigid housing,

a linear actuator secured to the housing,

a length of flexible tubing having opposite terminal ends secured to the housing between a rigid platen and a compressing member, one terminal end of the flexible tube for fluid connection to the pump and an opposite terminal end of the flexible tube for fluid connection to the dispense point, and the compressing member operable by the linear actuator to an extended position for partially compressing the tube against the platen while the pump is operating to pump the viscous substance through the flexible tube to the dispense point and a retracted position when dispensing is stopped so that a portion of the viscous substance is withdrawn from the dispense point into the tube.

2. A method of dispensing a viscous substance, comprising the steps of:

pumping the viscous substance from a source thereof through a flexible tube having one terminal end for fluid connection to a pump and an opposite terminal end for fluid connection to a dispense point, partially compressing the tube to a reduced internal diameter while the pump is pumping the viscous substance through the tube and the reduced internal diameter to the dispense point, stopping the pumping of the viscous substance and substantially simultaneously removing the compressing of the tube so that it rebounds to a full internal diameter.