Safety valve
Patent 5170818 Issued on December 15, 1992. Estimated Expiration Date: 
November 25, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
November 25, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2964310 2987071 3747635 Pressure relief valve Patent #: 4930553 InventorAssigneeApplicationNo. 797618 filed on 11/25/1991US Classes:137/469, Pop valves137/516.27, Sequential137/538, Piston-type valves137/539.5With followerExaminersPrimary: Nilson, Robert G.Attorney, Agent or FirmForeign Patent References
International ClassF16K 015/04AbstractA safety valve including a brass valve body having a through bore provided with a circular sharp-edged valve seat and another sharp edge. A valve stem carrying a ball valve and a biasing spring disposed in the through bore. A cap member screwed through onto the brass valve body and causing the ball valve to be seated on the sharp-edged valve seat and causing the ball valve to be positioned in close proximity to the other sharp edge. A plurality of radially vent holes formed in the brass valve body for venting fluid pressure to atmosphere when the ball valve becomes unseated from the sharp-edged valve seat. A lock nut for locking the cap member in position and a spring pin carried by the valve stem to permit the ball valve to be manually opened. | |
