Sphygmomanometer pressure relief valve

• US 3,893,478 A
• Filed: 02/04/1974
• Issued: 07/08/1975
• Est. Priority Date: 12/26/1972
• Status: Expired due to Term

• Current Assignee: Rudolph W. Peters
• Original Assignee: Rudolph W. Peters
• Inventors: Peters, Rudolph W.
• Primary Examiner(s): Klinksiek, Henry T.
• Application Number:
  US05/439,400
• Time in Patent Office: 519 Days
• Field of Search: 251/205,207,209,145,343,345,351,346 137/525.1,625.3,614.2 128/25C,6
• US Class Current: 137/614.2
• CPC Class Codes: F16K 15/142 the closure elements being shaped as solids of revolution, e.g. toroidal or cylindrical rings
• CPC Class Codes: F16K 31/5286 comprising a sliding valve
• CPC Class Codes: Y10T 137/88054 Direct response normally closed valve limits direction of flow

Abstract

An infinitely variable pressure relief valve for sphygmomanometers or similar instruments for controlling the rate of flow of compressed air from a zero flow to gradual pressure relief to substantially complete and instantaneous full pressure relief. The valve comprises an axially and radially displaceable collar means having a passage therein and a pin radially extending into said passage. Disposed within said passage in said collar means is a stationary member having a tapered axial vent slot and a helical slot wherein is tracked said pin axially and radially displaceable in unison with said collar means. A sealing means is provided which is axially and radially displaceable in unison with said collar means and said pin from a first position on a first side of said tapered slot and spaced therefrom, through a plurality of intermediate positions immediately adjacent said tapered slot at a plurality of locations along the axial length of said slot, to a second position on a second side of said tapered slot and spaced therefrom.

Claims

1. A valve for controlling the rate of flow of a fluid from a zero flow through gradual pressure relief to substantially complete and instantaneous full pressure relief, comprising:

an axially and rotationally displaceable collar having an axial passage therein and a pin radially extending into said passage;

a stationary first member generally disposed within said passage in said collar and having a helical slot wherein is tracked said pin, said pin and said helical slot constituting means for axially moving said collar on said first member when said collar is rotated with respect to said first member, said first member having a through axial passage providing an inlet and an axially opposed outlet, and said first member further having an outwardly opening vent slot having its effective cross sectional area axially increasing in one direction and being in fluid communication with said first member axial passage;

sealing means axially displaceable in said one direction and rotationally displaceable in unison with said collar and said pin from a first position on a first axially side of said vent slot and axially spaced therefrom, through a plurality of intermediate positions immediately radially adjacent said vent slot at a plurality of locations along the axial length of said vent slot, to a second position on the axially opposite side of said vent slot and axially spaced therefrom for correspondingly sealing said vent slot with respect to the atmosphere in said first position, providing increasing pressure relief for said first member axial passage through said intermediate positions and completely venting the pressure from said first member axial passage in said second position.

2. The valve of claim 1 wherein said collar is generally tubular and of right circular cylindrical shape, and said passage therein extends generally parallel to the central cylindrical axis of said collar.

3. The valve of claim 1 wherein said stationary first member has a bore therein wherein is received a second member rotationally and radially displaceable in unison with said collar.

4. The valve of claim 3 wherein said sealing means is secured to said second member.

5. The valve of claim 1 further including an annular slot extending about the periphery of said first member and intersecting said vent slot at only one location along said periphery and at least partially providing the fluid communication between said vent slot and said first member axial passage.

6. The valve of claim 5, wherein said first member has a diametric borehole therein, said borehole intersecting said annular slot at two locations along the extent of said annular slot and intersecting said first member axial passage between said two locations.

7. The valve of claim 6 wherein said helical slot interseCts said annular slot at one of said locations of intersection of said diametric borehole with said annular slot.

8. The valve of claim 1, including a one way valve within said axial passage of said first member and including a flexible bladder having a slit therein.