Patent ID: 7469875

Claim:
A pinch valve for regulating fluid flow comprising: a valve body on which the following elements are installed; a sleeve having a first side portion and opposite second side portion and a central longitudinal access; a close mechanism comprising: a first push pull member located adjacent said first side portion of said sleeve and adapted for linear movement toward and away from said sleeve; a first link having a first end, an opposite second end, and a first closure surface, said first end of said first link pivotally connected to said first push pull member and said first closure surface facing said sleeve; a second link having a first end, an opposite second end, and a second closure surface, said first end of said second link pivotally connected to said first push pull member and said second closure surface facing said sleeve; a second push pull member disposed opposite said first push pull member located adjacent said second side portion of said sleeve and adapted for linear movement toward and away from said sleeve; a third link having a first end, an opposite second end, and a third closure surface, said first end of said third link pivotally connected to said second push pull member and said third closure surface facing said sleeve; a fourth link having a first end, an opposite second end, and a fourth closure surface, said first end of said fourth link pivotally connected to said second push pull member and said fourth closure surface; facing said sleeve an open mechanism comprising: a first open follower pivotally connected to said second end of said first link and to said second end of said third link; a second open follower pivotally connected to said second end of said second link and to said second end of said fourth link; said first open follower being located adjacent said sleeve at an upper portion thereof and adapted for linear movement toward and away from said sleeve and said second open follower being located adjacent sleeve at a lower portion thereof and adapted for linear movement toward and away from said sleeve; said first, second, third, and fourth links defining a four bar linkage encircling said sleeve; wherein said first and second push pull members may be moved together to a closed position wherein said first and second side portions of said sleeve are pinched together by said first and second closure surfaces and said third and fourth closure surfaces respectively; and, wherein said first and second push pull members may be moved apart to an open position wherein said first and second open followers push said sleeve toward said centerline to assist in opening said sleeve.