Relief valve

• US 3,179,040 A
• Filed: 11/06/1961
• Issued: 04/20/1965
• Est. Priority Date: 11/06/1961
• Status: Expired due to Term

• Current Assignee: Robert E. Seltzer
• Original Assignee: Robert E. Seltzer
• Inventors: Seltzer, Robert E.
• Application Number:
  US04/150,353
• Time in Patent Office: 1,261 Days
• US Class Current: 100/43
• CPC Class Codes: B30B 9/3025 Extrusion chambers with adjustable outlet opening
• CPC Class Codes: Y10T 137/2607 With pressure reducing inlet valve
• CPC Class Codes: Y10T 137/7768 Pilot controls supply to pressure chamber
• CPC Class Codes: Y10T 137/7796 Senses inlet pressure

Claims

1. A HYDRAULIC VALVE COMPRISING A CHAMBER HAVING AN INLET PASSAGE, AN OUTLET PASSAGE, A PRESSURE FEEDBACK PASSAGE IN COMMUNICATION EXTERNALLY OF SAID CHAMBER WITH SAID OUTLET PASSAGE, AND A PRESSURE RELIEF PASSAGE, MOVABLE VALVE MEANS IN SAID CHAMBER FOR CONTROLLING COMMUNICATION BETWEEN SAID INLET AND SAID OUTLET PASSAGES AND BETWEEN SAID INLET AND SAID OUTLET PRESSURE RELIEF PASSAGE, SAID VALVE MEANS BEING SPRING-BIASED TO A POSITION PERMITTING COMMUNICATION BETWEEN SAID INLET PASSAGE AND SAID OUTLET PASSAGE AND BIASED BY PRESSURE IN SID OUTLET PASSAGE COMMUNICATED THROUGH SAID PRESSURE FEEDBACK PASSAGE TO A POSITION TENDING TO REDUCE COMMUNICATION BETWEEN SAID INLET PASSAGE AND SAID OUTLET PASSAGE, AND HYDRAULICALLY ACTUATED MEANS INCLUDING AN ELEMENT MOVABLE IN RESPONSE TO A PREDETERMINED PRESSURE IN SAID INLET PASSAGE AND OPERATIVELY CONNECTED TO SAID MOVABLE VALVE MEANS FOR TENDING TO MOVE SAID VALVE MEANS TO A POSITION PERMITTING COMMUNICATING BETWEEN SAID OUTLET PASSAGE AND SAID RELIEF PASSAGE WHEN THE PRESSURE IN SAID INLET PASSAGE EXCEEDS SAID PREDETERMINED PRESSURE.