Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
52 words
A gas sampler comprising a pump (12) and a valve (14), the pump (12) being controlled in dependence on the pressure across the valve (14) via an integrator (20), characterised in that the pump (12) is a rotary pump and that the valve (14) receives directly the output of the pump (12).
Claim 2
Dependent Claim
52 words
A gas sampler comprising a pump (12) and a valve (14), the pump (12) being controlled in dependence on the pressure across the valve (14) via an integrator (20), characterised in that the pump (12) is a rotary pump and that the valve (14) receives directly the output of the pump (12).
Claim 3
Dependent Claim
37 words
A gas sampler-according to claim 1, wherein the pressure across the valve (14) is detected by a pressure actuated switch (18), the position of which is detected so as to provide an input to the integrator (20).
Claim 4
Dependent Claim
24 words
A gas sampler according to claim 2 wherein the pressure actuated switch (18) senses the pressure between the pump (12) and the valve (14).
Claim 5
Dependent Claim
20 words
A gas sampler according to any one of the preceding claims wherein the integrator includes at least one logic element.
Claim 6
Dependent Claim
79 words
A gas sampler according to any one of claims 1 to 4 which further includes a detector (36) which detects when the pressure across the valve (14) is less than a predetermined value for less than a predetermined time, and a counter (34) which counts the time the pump (12) is running, the detector being adapted to stop the counter (34) when said predetermined time has elapsed until the pressure across the valve (14) has risen to said predetermined-value.
Claim 7
Dependent Claim
76 words
A gas sampler comprising a pump (12), a valve (14), characterised by: a detector (36) which detects when the pressure across the valve (14) is less than a predetermined value for less than a predetermined time, and a counter (34) which counts the-time the pump (12) is running, the detector being adapted to stop the counter (34) when said predetermined time has elapsed until the pressure across the valve (14) has risen to said predetermined value.
Claim 8
Dependent Claim
76 words
A gas sampler comprising a pump (12), a valve (14), characterised by: a detector (36) which detects when the pressure across the valve (14) is less than a predetermined value for less than a predetermined time, and a counter (34) which counts the-time the pump (12) is running, the detector being adapted to stop the counter (34) when said predetermined time has elapsed until the pressure across the valve (14) has risen to said predetermined value.
Claim 9
Dependent Claim
23 words
A gas sampler according to claim 6 further including a no-control circuit adapted to indicate aurally and/or visually when the counter is stopped.
Claim 10
Dependent Claim
23 words
A gas sampler according to claim 6 or claim 7 wherein the counter is fed from an oscillator, the oscillator having CMOS circuitry.
Claim 11
Dependent Claim
25 words
A gas sampler according to any one of the preceding claims wherein the pump is powered by a low inertia skew wound ironless D.C. motor.
Claim 12
Dependent Claim
22 words
A gas sampler according to any one of the preceding claims further including means for preventing excess current in the sampler circuitry.