Spring loaded split nut

• US 4,023,431 A
• Filed: 05/05/1975
• Issued: 05/17/1977
• Est. Priority Date: 05/05/1975
• Status: Expired due to Term

• Current Assignee: Bettis Corporation (Emerson Electric Company)
• Original Assignee: Bettis Corporation (Emerson Electric Company)
• Inventors: Pavlas, Garnet L.
• Primary Examiner(s): Scott, Samuel
• Assistant Examiner(s): Ratliff, Jr., Wesley S.
• Application Number:
  US05/574,619
• Time in Patent Office: 743 Days
• Field of Search: 74/424.8 A
• US Class Current: 74/424.94
• CPC Class Codes: F16K 31/143 the fluid acting on a piston
• CPC Class Codes: F16K 31/502 actuating pivotable valve members
• CPC Class Codes: Y10T 74/19805 Less than 360 degrees of contact between nut and screw

Abstract

Spring loaded member for automatically biasing a split nut toward engagement with a threaded rod, and rotatable cam member for effecting disengagement.

Claims

1. In an actuator having power driven linearly movable piston means for rotating a valve stem, and back-up means for rotating such valve stem, wherein such back-up means includes a rotatable threaded screw, means for coupling said piston means to said valve stem, and means for releasably engaging said screw with said coupling means, the improvement comprising:

means for biasing said engaging means toward a position resulting in screw engagement, said coupling means includes a retainer fixed to said piston means for movement therewith and having an unthreaded passageway therethrough for slidably receiving said screw, said engaging means includes a split nut having a threaded portion engageable with said screw, and said biasing means includes at least one spring.

2. The device of claim 1 wherein each of said retainer and said split nut includes a spring seat, said spring being positioned between said seats.

3. In an actuator having power driven linearly movable piston means for rotating a valve stem, and back-up means for rotating such valve stem, wherein such back-up means includes a rotatable threaded screw, means for coupling such piston means to said valve stem and means for releasably engaging said screw with said coupling means, the improvement comprising:

means for biasing said engaging means toward a position resulting in screw disengagement, said coupling means includes a retainer fixed to said piston means for movement therewith and having an unthreaded passageway therethrough for slidably receiving said screw, said engaging means includes a split nut having a threaded portion engageable with said screw, and said biasing means includes at least one spring.

4. The device of claim 3 wherein each of said retainer and said split nut includes a spring seat, said spring being positioned between said seats.