Patent · US Expired

Tank truck safety valve

US3999567A · kind A · utility

4Cited by
2References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 7, 1975
Grant dateDec 28, 1976
Priority date
Expiry dateJul 7, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/86919
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

The valve includes an upper or inner portion housing, a first spring which acts on the top of a valve member and normally urges it into sealing engagement with a seat, and a lower or outlet portion carrying an actuator pin having an inner end which disengageably abuts the underside of the valve member and is actuated to lift the valve member against the biasing force of the first spring. The valve actuator pin has a vent passage extending from its inner end to atmosphere. When the actuator pin is actuated to open the valve, the valve member covers the inlet of the vent passage. When the valve is closed, a smaller second spring, carried on the inner end portion of the valve actuator pin, urges the inner end of the actuator pin away from the valve member, thereby opening the vent passage inlet so that the portion of the valve body below the valve member is vented to atmosphere. This permits the discharge conduit connected to the valve to be gravity drained after the valve is closed. In the event the valve outlet portion and/or components connected thereto are struck with a hard force, such as during a collision, a groove in the discharge portion just below the valve seat breaks. This…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.