Spring seal

• US 4,352,498 A
• Filed: 03/07/1980
• Issued: 10/05/1982
• Est. Priority Date: 07/02/1979
• Status: Expired due to Term

• Current Assignee: GREENE, TWEED OF DELAWARE, INC.
• Original Assignee: Greene Tweed & Company Incorporated
• Inventors: Burke, John A., Gross, James B.
• Primary Examiner(s): Smith, Robert I.
• Application Number:
  US06/128,063
• Time in Patent Office: 942 Days
• Field of Search: 277/1, 277/27, 277/188 R, 277/188 A, 277/177
• US Class Current: 277/311
• CPC Class Codes: F16D 2121/02 Fluid pressure
• CPC Class Codes: F16D 2127/02 Release mechanisms
• CPC Class Codes: F16D 65/18 adapted for drawing members together , e.g. for disc brakes
• CPC Class Codes: F16J 15/32 with elastic sealings, e.g. O-rings

Abstract

A sealing ring firmly grips a movable piston, performs the normal sealing function, and when pressure is released on the piston the sealing ring pulls back on the piston so as to retract the piston. The sealing ring is designed so as to fit in a conventional seal or "O" ring groove without any modification of the groove.

Claims

1. A method comprising the steps of providing an annual seal assembly including a sealing ring and a back-up ring with the assembly having a generally trianular opening between said rings on its inner periphery, placing said assembly in a stationary rectangular groove having an axial length greater than the axial length of the assembly so as to provide a space on the high pressure side of the groove, deforming the sealing ring radially outwardly by contact between the outer periphery of a piston and a surface on the sealing which tapers from the high pressure side to said triangular opening, decreasing the size of said opening by said deforming step, using a piston whose outer diameter is greater than the inner diameter of the sealing ring tapered surface in the relaxed state of the sealing ring, applying pressure to the piston and to said space so that said sealing ring deforms axially into and occupies said triangular opening and biases said back-up ring radially inwardly, releasing pressure on said piston and seal assembly, and using said sealing ring as a return spring for retracting the piston a predetermined amount as said sealing ring returns to its original cross-sectional shape as deformed by the outer periphery of said piston.

2. A method in accordance with claim 1 including using a back-up ring which has a radially disposed side face defining one side of said generally triangular opening, spacing the outermost surface of said back-up ring from the bottom of the groove by a portion of said sealing ring.

3. A method in accordance with claim 1 including retracting the piston by said sealing ring for a distance between about 0.010 and 0.022 inch.