Pinch valve construction

• US 3,882,899 A
• Filed: 07/26/1973
• Issued: 05/13/1975
• Est. Priority Date: 07/26/1973
• Status: Expired due to Term

• Current Assignee: Guenter Ginsberg, Ronald Olin Simpson, Thomas John Godin
• Original Assignee: Guenter Ginsberg, Ronald Olin Simpson, Thomas John Godin
• Inventors: Ginsberg, Guenter, Godin, Thomas John, Simpson, Ronald Olin
• Primary Examiner(s): Nilson, Robert G.
• Application Number:
  US05/382,741
• Time in Patent Office: 656 Days
• Field of Search: 137/627.5 251/4,5,7
• US Class Current: 137/627.5
• CPC Class Codes: F04B 7/02 the valving being fluid-actuated
• CPC Class Codes: F04B 7/0275 and being deformable, e.g. membranes
• CPC Class Codes: F04B 9/12 the fluid being elastic, e.g. steam or air
• CPC Class Codes: F04B 9/1222 the return stroke being obtained by an elastic fluid under pressure
• CPC Class Codes: F16K 11/027 the fluid flowing through a constrictable tubular diaphragm
• CPC Class Codes: F16K 7/06 by means of a screw-spindle, cam, or other mechanical means F16K7/045 takes precedence
• CPC Class Codes: G01F 11/021 of the piston type G01F11/04 takes precedence
• CPC Class Codes: G01F 15/005 Valves valves in general F16K
• CPC Class Codes: Y10T 137/86919 Sequentially closing and opening alternately seating flow controllers

Abstract

A pneumatically controlled liquid transfer system for delivering a liquid from a source to a delivery location, said liquid source being provided with a pneumatic cylinder for driving the liquid from said source, a pneumatically operated pinch valve of the make-before-break type and flexible conduit paths leading through the valve to the delivery location. The make-before-break pinch valve comprises a valve shell having two pistons movable laterally therein. The shell has a window. One piston has a yoke, each arm thereof having a passageway, one aligned with the other. A stop extends between the arms of the yoke. One of the flexible conduits is arranged through the window between the first piston and the yoke and the other flexible conduit is arranged also through the window but within the aligned passageways and between the piston and post. The second piston is spring biased to bear against the second conduit to place same in a normally closed condition. The first conduit is normally open. The first piston is acted upon by an external force such as air pressure to move same to a first condition wherein the piston pinches the first flexible conduit against the yoke, closing said conduit without overcoming the bias of the second piston to open the second conduit. Continued force exercised upon said first piston causes the same to move laterally within the housing to a second condition overcoming the spring bias of the second piston, to open the second conduit while the first conduit is retained in closed position. The second piston by virtue of its spring bias, will force the yoke back into its first position once the pressure on the first piston is relaxed. A manual override is provided operative upon the second piston to lock the same in open condition so that both conduits are open. This last mentioned position is utilized during down time of the apparatus concerned.

Claims

1. A pinch valve of the make-before-break type operable upon at least a pair of flexible conduits each capable of carrying a liquid, said pinch valve comprising:

a valve shell having side and end walls, first and second pistons linearly movable sequentially therein and a stop member on said shell interposed between said first and second pistons, said shell having window means in opposite side walls thereof and said flexible conduits being threaded through said window means bEtween said pistons, actuating means coupled to said first piston for moving same in a first direction and biasing means coupled to said second piston for urging the second piston in a direction opposed to said first direction, said first piston being linearly drivable toward said second piston, first to change the condition of one of said flexible conduits while maintaining the condition of the other of said flexible conduits, thereafter continuing linear movement in the first direction to overcome the biasing means and changing the condition of the other of said flexible conduits.

2. The pinch valve as claimed in claim 1 in which yoke means is provided secured to said second piston, said stop member in traversing relation therewith, said other conduit being threaded through said yoke means and between said second piston and said stop member.

3. The pinch valve as claimed in claim 2 in which said yoke means includes a rib formation adapted to engage said one conduit upon actuation of said first piston.

4. The pinch valve as claimed in claim 2 in which each piston has a plunger extending from the housing and pressure exerting means are arranged to operate upon the plunger of said first piston.

5. The pinch valve as claimed in claim 4 in which means are provided operable upon said second piston for maintaining said second piston independent of the operation of said first piston, and said last-mentioned means comprise cam means carrying the free end of the plunger of said second piston and operable upon the shell end adjacent thereto.

6. The pinch valve as claimed in claim 5 in which said cam means comprise a cylindrical member having an eccentrically mounted shaft, said plunger end coupled to said shaft and said member being rotatable to move said plunger laterally to place said second piston in a location where the changed condition of said other flexible conduit is maintained and stop means on said member for retaining same temporarily in its rotated condition.

7. The pinch valve as claimed in claim 1 in which means are provided operable upon said second piston for maintaining said second piston independent of the operation of said first piston.

8. A pinch valve of the make-before-break type capable of operating upon at least a pair of flexible conduits capable of carrying a liquid, said valve comprising:

a valve shell having opposite side and end walls, first and second pistons linearly movable within said shell and a stop member on said shell interposed between said first and second pistons, each of said pistons having a plunger extending outward from opposite end walls of said shell, said shell having window means in opposite side walls thereof and said flexible conduits being threaded through said window means between said pistons, actuating means for driving the first piston linearly in a first direction toward the second piston and biasing means coupled to the second piston for urging the second piston in a direction opposed to the first direction, said first piston being linearly movable toward the second piston first to change the condition of one of said flexible conduits while maintaining the condition of the other of said flexible conduits unchanged, thereafter said first piston being further movable in said first direction to overcome the said biasing means and changing the condition of the other of said flexible conduits, and eccentric wheel means operatively coupled to the plunger of said second piston to overcome said biasing means prior to actuation of said first piston.

9. A pinch valve of the make-before-break type operable upon at least a pair of flexible conduits each capable of carrying a liquid, said pinch valve comprising:

a valve shell having opposite side and end walls, first and second pistons arranged within the shell for linear movement along a path within said shell, window means formed in the opposite side walls of said shell, yoke means carried by said second piston and located between said first and Second pistons, stop means on the shell extending inwardly through said yoke means and across the path of movement of said first and second pistons, actuating means coupled to said first piston to drive said first piston in a first direction and means for biasing said second piston in a second direction opposed to said first direction, the flexible conduits being threadable through said window means into said shell and across the path of movement of said pistons, the first flexible conduit arranged to pass between said first piston and said yoke, and the second flexible conduit arranged to pass through said yoke between said stop means and said second piston, said actuating means arranged to drive said first piston in said first direction against said yoke means changing the condition of said first conduit while maintaining the condition of said second conduit and thereafter to move further in said first direction maintaining the changed condition of said first conduit but overcoming the biasing means and changing the condition of said second conduit.