06983867 is referenced by 34 patents and cites 127 patents.

A material dispensing pump includes a drip prevention system and method so as to avoid undesired dripping of the dispensed fluid. In one example, the fluid path is sealed. Positive pressure is applied to the fluid during a dispensing operation to present the fluid to the auger-style pump at a desired rate. Between dispensing operations, or when dispensing is completed, the fluid is placed in suspension, for example by applying a negative pressure, thereby preventing the fluid from being inadvertently released at the dispense tip. In addition, following a dispensing operation, the pump dispensing controller can be programmed to reverse the rotation of the feed screw, in order to draw the material in a reverse direction and to further suspend the fluid.

Title
Fluid dispense pump with drip prevention mechanism and method for controlling same
Application Number
10/424273
Publication Number
6983867 (B1)
Application Date
April 28, 2003
Publication Date
January 10, 2006
Inventor
Jeffrey P Fugere
Sandown
NH, US
Agent
Mills & Onello
Assignee
DL Technology
MA, US
IPC
G01F 11/20
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