GAUGE RECORDING MAXIMUM PRESSURE

• US 3,779,080 A
• Filed: 07/26/1971
• Issued: 12/18/1973
• Est. Priority Date: 07/26/1971
• Status: Expired due to Term

• Current Assignee: TP Industrial Incorporated
• Original Assignee: Charles Harry Smith
• Inventors: Smith, Charles Harry
• Primary Examiner(s): Queisser, Richard C.
• Assistant Examiner(s): Yasich, Daniel M.
• Application Number:
  US05/166,016
• Time in Patent Office: 876 Days
• Field of Search: 73/396 116/70
• US Class Current: 73/709
• CPC Class Codes: G01L 19/10 mechanical
• CPC Class Codes: G01L 7/086 with optical transmitting or indicating means

Abstract

Device for visual indication of a maximum fluid pressure condition reached during a given interval of time. Useful for the in-flight recording of fluid pressure condition e.g., in the reduction gear box of a jet engine where excessive pressures are indicative of incipient failures, the device comprises a body having a cavity in fluid pressure communication with system fluid, an indicator movable relative to the body cavity in response to changes in system fluid pressure, and locking means limiting indicator travel to a single direction indicative of a relatively higher pressure condition in the system.

Claims

1. Device for indicating highest fluid pressure experienced over time in a system experiencing varying pressure conditions, comprising a pressure resistant body defining a body cavity and having a rod passing in the top wall portion of the device and communicating with said cavity and a boss on said top wall eccentric to said opening and port means communicating said cavity continuously with system fluid pressure, a piston mounted and sealed within the body cavity between said opening and said port means for fluid pressure responsive movement, an indicator rod carried by the piston for varying extension through said rod passing opening responsive to piston movement;

and locking means limiting said indicator rod travel to one way movement responsive to a higher experienced pressure in the system comprising a locking member having a ring portion encircling the indicator rod, said boss defining a pivot shoulder to operatively coact with the locking member so that the member ring portion binds the indicator rod against return movement if the pressure drops below the highest experienced pressure in the system.

2. Fluid pressure indicating device according to claim 1 including also spring means resiliently biasing said member ring portion into engagement with said boss.

3. Fluid pressure indicating device according to claim 1 including also a piston support, said piston support comprising a diaphragm fluid tightly secured to the body cavity wall and extending transversely of the cavity, said diaphragm being centrally flexible for movably supporting the piston within said cavity.

4. Fluid pressure indicating device according to claim 3 in which said indicator rod is carried by the piston face remote to said cavity port and for longitudinal axial movement into and out of said cavity to variously project through said rod passing opening beyond the body.

5. Fluid pressure indicating device according to claim 4 including also indicator rod travel guide means comprising structure slidably engaging the cavity wall and adapted to move with the rod in guiding relation.

6. Fluid pressure indicating device accordng to claim 1 in which said rod is rectangular in cross section and has sharply defined longitudinally extended corners and flats therebetween.

7. Fluid pressure device according to claim 7 including also a finger engageable tab projecting from the ring portion of the locking member for pivoting said member about said boss to release the member ring portion from engagement with said rod.