×

Air trap for shutting off flexible plastic tubing

  • US 4,925,152 A
  • Filed: 01/19/1989
  • Issued: 05/15/1990
  • Est. Priority Date: 01/21/1988
  • Status: Expired due to Fees
First Claim
Patent Images

1. An air trap for shutting off flexible plastic tubing, comprisinga body having a hollow interior and provided with an inlet port,a diaphragm disposed in said hollow interior and defining in said hollow interior a pressure chamber, which communicates with said inlet port,a guide stem, which is secured to said diaphragm on that side thereof that is opposite to said pressure chamber,a flat head coupled to said guide stem,valve means, which are connected to said inlet port and are operable to selectively pressurize and pressure-relieve said pressure chamber through said inlet port,a receptacle defining outside said body a passage for receiving a flexible tubing,squeezing means, which are operatively connected to and operable by said guide stem to release said tubing in said passage in response to gas pressure in said pressure chamber, andspring means biasing said flat head and guide stem to operate said squeezing means by said guide stem to squeeze said tubing in said passage in response to a pressure relief of said pressure chamber, whereinsaid spring means comprise two concentric compression springs, which are arranged one in the other and engage said flat head and urge it toward said pressure chamber,said valve means are electrically energizable to pressurize said pressure chamber and electrically deenergizable to pressure-relieve said pressure chamber,a control circuit for energizing and deenergizing said valve means is connected to said valve means, andsaid two compression springs are electrically connected in series in said control circuit.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×