Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
208 words
A device for controlling a flow of liquid from a pressure source, the device comprising a control valve having an inlet from the pressure source, an outlet, a valve chamber connecting the inlet and the outlet, and a control member movable between positions in which the outlet is open and closed with respect to the inlet, wherein the device further comprises a resilient annular diaphragm; a disc, which constitutes the aforesaid control member, supported centrally of the said diaphragm; an annular valve surface formed on the outlet of the valve chamber against which the control member abuts when in the closed position; a sub chamber partitioned from the valve chamber by the diaphragm and the control member; a bleeder connecting the sub chamber with the inlet; a pilot valve adapted to control the liquid pressure in the sub chamber whereby to control the position of the control member, and a perforate flow restrictor supported on the control member centrally of the annular valve surface and axially movably with respect to the control member, the flow restrictor being adapted to contact the valve surface as the control member approaches the closed position thereby to reduce the flow through the outlet before the latter is closed by the control member.
Claim 2
Independent Claim
208 words
A device for controlling a flow of liquid from a pressure source, the device comprising a control valve having an inlet from the pressure source, an outlet, a valve chamber connecting the inlet and the outlet, and a control member movable between positions in which the outlet is open and closed with respect to the inlet, wherein the device further comprises a resilient annular diaphragm; a disc, which constitutes the aforesaid control member, supported centrally of the said diaphragm; an annular valve surface formed on the outlet of the valve chamber against which the control member abuts when in the closed position; a sub chamber partitioned from the valve chamber by the diaphragm and the control member; a bleeder connecting the sub chamber with the inlet; a pilot valve adapted to control the liquid pressure in the sub chamber whereby to control the position of the control member, and a perforate flow restrictor supported on the control member centrally of the annular valve surface and axially movably with respect to the control member, the flow restrictor being adapted to contact the valve surface as the control member approaches the closed position thereby to reduce the flow through the outlet before the latter is closed by the control member.
Claim 3
Dependent Claim
52 words
A device in accordance with claim 1, wherein the control member has an aperture and a pin extends through said aperture so as to define the dimensions of an annular passageway which constitutes the said bleeder and to ensure that said passageway cannot become obstructed by solid particulate material in the liquid.
Claim 4
Dependent Claim
32 words
A device in accordance with claim 2, wherein the pin is of tapered form and is arranged to reduce the dimensions of the bleeder as the control member approaches the closed position.
Claim 5
Dependent Claim
47 words
A device in accordance with claim 3, wherein the perforate flow restrictor is of hollow conical form, is supported on the control member with its annular base adjacent the latter and is adapted to be received within the outlet as the control member approaches the closed position.