Pinch valve formed from a wire helix

Claim 2

In a valve of the type which includes a length of flexible tubing, the opposite sides of the wall of the tubing being pinched together to control the flow of fluid therethrough, the improvement which comprises a resilient wire helix having spacing between adjacent turns which is variable between a first pair of adjacent turns and a second pair of adjacent turns such that the opposite walls of said tubing, when engaged between said first pair of turns, will be pinched to stop the flow of fluid, and, when engaged between said second pair of turns, will be substantially undistorted to allow substantially free flow of fluid, and means to mount said wire helix on said tubing for movement between said first and second pair of turns.

Claim 3

The invention defined in claim 1, wherein said first pair of adjacent turns are connected with a plurality of helically wound, closely spaced turns of wire of uniform diameter.

Claim 4

The invention defined in claim 2, wherein said second pair of adjacent turns are connected with a plurality of helically wound, widely spaced turns of wire.

Claim 5

The invention defined in claim 1, wherein said means to mount said helix comprises a plurality of turns of wire of said helix having an inside diameter sufficient to freely, slideably and rotatably received said tubing therein.

Claim 6

The invention defined in claim 1, wherein said means to mount said helix also includes stop means projecting from said helix to hold said helix when said tubing is moved between said first and second pair of turns.

Claim 7

The invention defined in claim 5, wherein said helix includes a plurality of turns of uniform diameter and said stop means comprising at least one turn of said helix disposed to project outwardly of the helix.

Claim 8

The invention defined in claim 1, wherein said helix includes two sections of helically wound turns of wire having inside diameter sufficient to freely receive said tubing therein, said two sections being joined to each other by a plurality of other turns of said helix which are disposed entirely exteriorly of said tubing.

Claim 9

The invention defined in claim 7, wherein at least some of said other turns of wire are closely spaced and are joined with each of said respective first two sections by at least one widely spaced turn of wire.

Claim 10

The invention defined in claim 7, wherein said two sections of helically wound turns of wire are also connected by a rigid handle.

Claim 11

The invention defined in claim 9, wherein said two sections of helically wound turns of wire are disposed at an angle with respect to each other and said handle is a straight element connected with the extremities of said two sections.

Claim 12

Method of forming a valve of the type which includes a flexible tubing and a pinch-valving element for use with the tubing for compressing the opposite sides of the wall thereof to stop the flow of fluid, comprising the steps of: a. applying axially directed force in tension to a pair of adjacent turns of a resilient multi-turn wire helix the normal spacing between adjacent turns of said helix being such that said tubing will be pinched closed when positioned therebetween, said axially directed force being sufficient to deform said adjacent turns beyond the elastic limit of said wire such that when said tension is released the distance between said pair of turns will be sufficient to permit said tubing to pass therebetween without being pinched to any substantial degree; b. releasing said tension; c. bending at least one turn of wire of said helix angularly with respect to the rest of the helix to form a stop means.

Claim 13

Method of forming a valve of the type which includes a flexible tubing and a pinch-valving element for use with the tubing for compressing the opposite sides of the wall thereof to stop the flow of fluid, comprising the steps of: a. applying axially directed force in tension to a pair of adjacent turns of a resilient multi-turn wire helix the normal spacing between adjacent turns of said helix being such that said tubing will be pinched closed when positioned therebetween, said axially directed force being sufficient to deform said adjacent turns beyond the elastic limit of said wire such that when said tension is released the distance between said pair of turns will be sufficient to permit said tubing to pass therebetween without being pinched to any substantial degree; b. releasing said tension; c. bending at least one turn of wire of said helix angularly with respect to the rest of the helix to form a stop means.

Claim 14

The method defined in claim 11, wherein the diameter of said helix is uniform along the length thereof and adjacent turns are normally in abutting relationship to each other.

Claim 15

The method defined in claim 11, which includes the additional steps of: d. inserting said tubing axially into said undeformed helix, and; e. leading one end of the tubing from the interior of the tubing to the exterior thereof through the space between said pair of turns.

Claim 16

The method of claim 11, which includes the additional steps of: d. inserting said tubing coaxially into said undeformed helix, and; e. leading one end of the tubing out of the helix between said pair of deformed turns.

Claim 17

The method of claim 11, which includes the additional steps of: d. applying said axially directed force in tension to a pair of adjacent turns located medially of the length of said helix; e. applying said axially directed force in tension to deform another pair of adjacent turns located medially of the length of said helix and spaced from said first mentioned pair of turns, and; f. releasing said force in tension against both of said pairs of adjacent turns.

Claim 18

The method of claim 14, which includes the additional steps of: g. bending another turn of wire angularly with respect to the rest of the helix to form stop means at both extremities of the helix, and; h. connecting a rigid handle between said two stop means.

Claim 19

The method of claim 15, which includes the additional steps of: i. inserting one end of a length of said tubing coaxially into one extremity of said helix and advancing said one end to one pair of said deformed adjacent turns; j. further advancing said tubing and withdrawing said one end from the helix through the space between said deformed pair of turns; k. further advancing said tubing and reinserting said one end into the interior of the helix through the space between said another pair of deformed turns of wire, and; l. further advancing said tubing and withdrawing said one end outwardly from the other extremity of the helix.