Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
244 words
A valve system for use in a liquid feeding system in which in operation liquid is fed by an electric pump to a delivery means, said valve system comprising: a main outlet, a check valve, and an inlet connectable via a said valve to said main outlet, a bypass valve and a bypass outlet connectable to said inlet via said bypass valve which opens in response to a sudden increase in pressure at said main outlet, a first pressure switch in communication with said main outlet and settable to either a first condition or to a second condition when the pressure applied to said first pressure switch is less than or exceeds a predetermined threshold value respectively, a second pressure switch in communication with said inlet and settable to either a first condition or to a second condition when the pressure applied to said second switch is less than or exceeds a predetermined threshold value respectively, said first and second pressure switches being connected together in such a manner than when the pressure switches are both in said first condition or are both in said second condition a switch on path for said pump is closed enabling operation of the pump, the arrangement further being such that when said bypass valve is opened by said sudden pressure increase said second pressure switch is switched from its second condition to its first condition for switching off said pump by opening the associated switch on path.
Claim 2
Dependent Claim
244 words
A valve system for use in a liquid feeding system in which in operation liquid is fed by an electric pump to a delivery means, said valve system comprising: a main outlet, a check valve, and an inlet connectable via a said valve to said main outlet, a bypass valve and a bypass outlet connectable to said inlet via said bypass valve which opens in response to a sudden increase in pressure at said main outlet, a first pressure switch in communication with said main outlet and settable to either a first condition or to a second condition when the pressure applied to said first pressure switch is less than or exceeds a predetermined threshold value respectively, a second pressure switch in communication with said inlet and settable to either a first condition or to a second condition when the pressure applied to said second switch is less than or exceeds a predetermined threshold value respectively, said first and second pressure switches being connected together in such a manner than when the pressure switches are both in said first condition or are both in said second condition a switch on path for said pump is closed enabling operation of the pump, the arrangement further being such that when said bypass valve is opened by said sudden pressure increase said second pressure switch is switched from its second condition to its first condition for switching off said pump by opening the associated switch on path.
Claim 3
Dependent Claim
39 words
Apparatus according to claim 1, wherein the two pressure switches are in such a serial connection in the pump switch-on path that the latter is closed whenever the two pressure switches are both in an on-position or an off-position.
Claim 4
Dependent Claim
28 words
Apparatus according to claim 1 or 2, wherein the bypass valve and the check valve are arranged in a common valve chamber also incorporating the two pressure switches.
Claim 5
Dependent Claim
39 words
Apparatus according to claim 3 wherein the first pressure switch is connected to a liquid control path which begins at the output side behind the check valve and which leads to an opening control means for the bypass valve.
Claim 6
Dependent Claim
19 words
Apparatus according to claim 4, characterized in that the opening control means for the bypass valve is adjustably biased.
Claim 7
Dependent Claim
20 words
Apparatus according to claim 3 wherein the second pressure switch is connected to a valve chamber of the shunt valve.
Claim 8
Dependent Claim
28 words
Apparatus according to claim 1 or 2 wherein the second pressure switch is arranged to close in its pressure applied condition an energizing circuit for a heating source.
Claim 9
Dependent Claim
22 words
Apparatus according to claim 1 or 2, characterized that the pressure switches are screwed into threaded holes provided in the valve body.
Claim 10
Dependent Claim
21 words
Apparatus according to claim 1 or 2 wherein the pressure switches are secured to means being formed at the valve body.