Butterfly valve
Patent 3990675 Issued on November 9, 1976. Estimated Expiration Date: 
November 9, 1993. 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 9, 1993. 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 2726103 2867238 3192945 3360283 3453006 3589678 3667726 3750698 3782684 3825030 InventorAssigneeApplicationNo. 531345 filed on 12/10/1974US Classes:251/148, Pipe coupling or union137/375, Jacketed251/306Head and/or seat packingExaminersPrimary: Cline, William R.Attorney, Agent or FirmForeign Application Priority Data1973-12-11 FRAbstractA butterfly valve for pipes having smooth ends comprising a body constituted by a metal casing of generally tubular shape with two dimensional bosses provided with coaxial passages. A layer of elastomer material externally and internally envelops the totality of the metal casing. Two shafts are rotatably mounted in the coaxial passages and support a butterfly within the body. The body includes at one of the extremities thereof an end portion which permits connection of the valve to a pipe by interfitting thereof. The other end of the body can be connected in various ways with the other pipe either as a male or a female fitting with associated annular lips. | |
