Flexible tubular members and valves incorporating such members

Claim 2

A flexible tubular member of circular cross section over an axial region between the ends thereof and having opposing shoulders at said region which divide the tube section at the shoulders into a first portion and a second portion which includes the shoulders, the circumferential internal length of the first portion being equal to the circumferential internal length of the second portion so that the tube can be pinched closed by a wrapping of the first portion into the second portion and over the shoulders, while the flexible tubular member is held in a rigid tube neatly matching the outside diameter of the flexible tubular member, said shoulders tapering away to nothing in the axial directions away from the center of the region, and wherein the tubular member in cross section is of constant thickness to one side of the shoulders defining a thick tube portion, and of constant thickness to the other side of the shoulders defining a thin tube portion and said thick and thin portions may each extend circumferentially over approximately half of the wall sectional length.

Claim 3

A tube assembly comprising a flexible tubular member of circular cross section having radially outward projecting flange formations at its ends, said tubular member having opposing shoulders over an axial region between said ends, which divide the tubular member section at its shoulders into a first portion and a second portion which includes the shoulders, the circumferential internal length of the first portion being equal to the circumferential length of the second portion so that the tubular member can be pinched closed by a wrapping of the first portion into the second portion and over the shoulders, while the flexible tubular member is held in a rigid tube neatly matching the outside diameter of the flexible tubular member, said shoulders tapering away to nothing in the axial directions away from the centre of the region, and a fabric reinforcing sleeve which extends between the said end flange formations, said sleeve having its own end formations adapted to be held securely (within) with the flange formations of said flexible tubular member in a pinch valve, said sleeve surrounding the outside of the tubular member, which is nonadhesively separable from the tubular member, and which is constructed to reinforce the tubular member against rupture as a result of high internal pressure, and to flex when pinched.

Claim 4

A tube assembly comprising a flexible tubular member of circular cross section having radially outward projecting flange formations at its ends, said tubular member having opposing shoulders over an axial region between said ends, which divide the tubular member section at its shoulders into a first portion and a second portion which includes the shoulders, the circumferential internal length of the first portion being equal to the circumferential length of the second portion so that the tubular member can be pinched closed by a wrapping of the first portion into the second portion and over the shoulders, while the flexible tubular member is held in a rigid tube neatly matching the outside diameter of the flexible tubular member, said shoulders tapering away to nothing in the axial directions away from the centre of the region, and a fabric reinforcing sleeve which extends between the said end flange formations, said sleeve having its own end formations adapted to be held securely (within) with the flange formations of said flexible tubular member in a pinch valve, said sleeve surrounding the outside of the tubular member, which is nonadhesively separable from the tubular member, and which is constructed to reinforce the tubular member against rupture as a result of high internal pressure, and to flex when pinched.

Claim 5

A tube assembly according to claim 2, wherein the section of the tubular member at said shoulders defines two opposite segments which contain the shoulders and two further opposite segments, each of which is of constant, equal thickness.

Claim 6

A tube assembly according to claim 3, wherein the tube assembly is straight, and apart from the shoulders is of constant circular section.

Claim 7

A pinch valve including a valve casing defining a circular bore, a tube assembly neatly matched to and located in said bore, said tube assembly comprising an internal flexible tubular member having radially outwardly projecting flange formations at its ends and surrounded by a sleeve of fabric which is non-adhesively separable from the tubular member and which extends between said end flange formations, said sleeve having its own end formations adapted to be held securely by the flange formations of said flexible tubular member, said sleeve serving to reinforce the tubular member against rupture as a result of high internal pressure, and which flexes when pinched, said tubular member being of circular cross section over an axial region between the ends thereof, and having opposing shoulders at said region which divide the tube section at said shoulders into a first portion and a second portion which includes the shoulders, the circumferential internal length of the first portion being equal to the circumferential internal length of the second portion, said shoulders tapering away to nothing in the axial directions away from the centre of the region, and the valve including pinching means for pinching the assembly by a wrapping of the first portion into the second portion and over the shoulders while the tube assembly is supported in the bore of the casing.

Claim 8

A pinch valve including a valve casing defining a circular bore, a tube assembly neatly matched to and located in said bore, said tube assembly comprising an internal flexible tubular member having radially outwardly projecting flange formations at its ends and surrounded by a sleeve of fabric which is non-adhesively separable from the tubular member and which extends between said end flange formations, said sleeve having its own end formations adapted to be held securely by the flange formations of said flexible tubular member, said sleeve serving to reinforce the tubular member against rupture as a result of high internal pressure, and which flexes when pinched, said tubular member being of circular cross section over an axial region between the ends thereof, and having opposing shoulders at said region which divide the tube section at said shoulders into a first portion and a second portion which includes the shoulders, the circumferential internal length of the first portion being equal to the circumferential internal length of the second portion, said shoulders tapering away to nothing in the axial directions away from the centre of the region, and the valve including pinching means for pinching the assembly by a wrapping of the first portion into the second portion and over the shoulders while the tube assembly is supported in the bore of the casing.