×

Ball valve

  • US 4,932,436 A
  • Filed: 09/20/1989
  • Issued: 06/12/1990
  • Est. Priority Date: 04/28/1989
  • Status: Expired due to Fees
First Claim
Patent Images

1. A ball valve comprising:

  • a valve casing having an upstream passageway and a downstream passageway for a fluid, accommodating therein an upstream ball seat and a downstream ball seat, and defining a cavity between said upstream ball seat and said downstream ball seat;

    a ball provided with a through hole, accommodated in said cavity, and brought into sealing contact with said upstream ball seat and said downstream ball seat at the outer periphery thereof;

    a valve stem having one end thereof fixed to said ball;

    a valve handle fixed to the other end of said valve stem;

    said ball being rotated by a rotating operation of said valve handle for opening and closing said ball valve;

    a check valve accommodated in said through hole of said ball and biased toward said upstream passageway of said valve casing;

    a path formed on said ball and, when said ball valve is closed, causing said downstream passageway and said cavity to communicate with each other; and

    a connection port formed on said valve casing so as to communicate with said cavity, and having a free end thereof connected to one end of a nipple having the other end thereof covered with a cap.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×