Flapper check valve

Claim 2

A check valve comprising a valve body formed in two parts, a downstream part of said valve body defining a generally bell-shaped flow chamber and an outlet from said flow chamber, and an upstream part of said valve body including an inlet and a shaft mounted transversely with respect to said inlet, said shaft carrying a pair of half-discs mounted for movement from a generally coplanar closed position with said half-discs in contact with a valve seat formed in said upstream valve part to a fully open position with said half-discs resting against stop means within said downstream part of the valve body and wherein said stop means comprise a pair of projections integrally formed with the downstream part of the valve body and said half-discs have recesses located to mate with said projection, and including means allowing said half-discs to move into back-to-back contact when the valve is in fully open condition.

Claim 3

The valve of claim 1 wherein said shaft mounted transversely with respect to said inlet is mounted at its ends in a pair of ears extending from said upstream body part into said flow chamber.

Claim 4

The valve of claim 1 wherein each half-disc is generally flat and has a downstream face with an arcuate outer edge and said recesses are located at said arcuate outer edge.

Claim 5

The valve of claim 3 wherein there are two of said recesses in each half-disc.

Claim 6

The valve of claim 3 wherein said downstream face as a slanted portion extending to a straight inner edge and a pair of spaced hinge ears project from said slanted portion, one of said hinge ears being located near one end of said straight inner edge and the other of said hinge ears being spaced from an opposite end of said straight inner edge by a distance at least as great as the width of said one of said hinge ears.

Claim 7

A flapper check valve comprising a generally bell-shaped downstream valve body enclosing a flow chamber, said downstream body portion having a cylindrical end defining an outlet from said flow chamber said cylindrical end being formed with an external circumferential groove and a wall widening from said cylindrical end to terminate in an annular peripheral flange, an upstream valve body portion having a flange opposed to and secured to the flange of said downstream body portion, said upstream body portion having a cylindrical end formed with an external circumferential groove and defining an inlet to said flow chamber, an axial opening through said upstream valve body portion and a transverse rib extending across said opening, a pair of ears extending into said flow chamber from said upstream body portion and a shaft mounted in said ears and extending parallel to said transverse rib, a pair of identical half-discs pivotally mounted on said shaft for movement from a generally coplanar closed position in contact with a valve seat area of said upstream part to a back-to-back fully open position, stop means integrally formed within said downstream body portion and recesses in downstream faces of said half-discs positioned to mate with said stop means in said fully open position, and a coiled spring on said shaft for closing said valve.

Claim 8

A flapper check valve comprising a generally bell-shaped downstream valve body enclosing a flow chamber, said downstream body portion having a cylindrical end defining an outlet from said flow chamber said cylindrical end being formed with an external circumferential groove and a wall widening from said cylindrical end to terminate in an annular peripheral flange, an upstream valve body portion having a flange opposed to and secured to the flange of said downstream body portion, said upstream body portion having a cylindrical end formed with an external circumferential groove and defining an inlet to said flow chamber, an axial opening through said upstream valve body portion and a transverse rib extending across said opening, a pair of ears extending into said flow chamber from said upstream body portion and a shaft mounted in said ears and extending parallel to said transverse rib, a pair of identical half-discs pivotally mounted on said shaft for movement from a generally coplanar closed position in contact with a valve seat area of said upstream part to a back-to-back fully open position, stop means integrally formed within said downstream body portion and recesses in downstream faces of said half-discs positioned to mate with said stop means in said fully open position, and a coiled spring on said shaft for closing said valve.

Claim 9

The valve of claim 6 wherein ends of said spring extend radially outward therefrom to permit said half-discs to assume said back-to-back position.

Claim 10

The valve of claim 7 wherein said ends of the spring are received in grooves in said downstream faces.

Claim 11

The valve of claim 6 wherein said flanges are secured together by bolts and including an O-ring seal between said flanges.

Claim 12

A flapper check valve having a two part valve body, one part of said valve body defining an inlet and a flow passage and carrying a pair of pivotally mounted half-discs and including a seat for said half-discs when the valve is in closed condition, the other part of said valve body enclosing a generally bell-shaped flow chamber and having means defining an outlet from said flow chamber said other part having two integrally formed projections serving as stops for said half-discs when the valve is in fully open condition with said flow passage in communication with said flow chamber, said half-discs being mounted to pivot about a shaft from a generally coplanar closed position through an angle of about 90° to a back-to-back open position, said half-discs having recesses for mating with said stops when said half-discs are back-to-back in said open position.

Claim 13

A flapper check valve having a two part valve body, one part of said valve body defining an inlet and a flow passage and carrying a pair of pivotally mounted half-discs and including a seat for said half-discs when the valve is in closed condition, the other part of said valve body enclosing a generally bell-shaped flow chamber and having means defining an outlet from said flow chamber said other part having two integrally formed projections serving as stops for said half-discs when the valve is in fully open condition with said flow passage in communication with said flow chamber, said half-discs being mounted to pivot about a shaft from a generally coplanar closed position through an angle of about 90° to a back-to-back open position, said half-discs having recesses for mating with said stops when said half-discs are back-to-back in said open position.

Claim 14

The valve of claim 10 wherein each of said valve body parts as a cylindrical end formed with an external circumferential groove for attachment of said valve to other piping elements.

Claim 15

The valve of claim 10 wherein said half-discs are generally flat each half-disc has a downstream face with an arcuate outer edge, said recesses being a pair of spaced recesses in said downstream face at said arcuate outer edge, and including a coiled spring on said shaft for closing said valve, ends of said spring being received in grooves in said downstream faces of the half-discs.