Suction pressure relieving system for a rotary vane compressor

Claim 2

In a rotary vane gas compressor system including an inlet suction control valve, a rotary vane compressor having inlet and discharge manifolds, and a compressed gas receiver, the improvements comprising: valve means interposed between the compressed gas receiver and the compressor discharge manifold for preventing flow of compressed gas in the receiver back into the rotary compressor; and auxiliary chamber means connected to the rotary compressor inlet manifold and having a preselected minimum volume for reducing the static shutdown pressure across the rotary compressor to a value not greater than a maximum startup inlet pressure limit.

Claim 3

The improvements of claim 1 further including: a oil demister tank connected to the compressed gas receiver upstream in the direction of normal gas flow from the receiver and downstream with respect to the valve means.

Claim 4

The improvements of claim 1 further including: an oil reservoir interposed between the valve means and the compressed gas receiver; an oil feed conduit connecting the oil reservoir with the rotary compressor; and an oil flow regulating valve interposed in the oil feed conduit for regulating the flow of oil from the reservoir to the rotary compressor.

Claim 5

The improvements of claim 3 still further including: an oil filter located in the oil feed conduit between the reservoir and the oil flow regulating valve.

Claim 6

An automatic inlet pressure relieving apparatus for a rotary pneumatic compressor, said compressor having an inlet, a discharge manifold and a high-pressure gas discharge conduit connecting said discharge manifold to a high-pressure gas receiver, said pressure-relieving apparatus comprising: suction control throttle valve means connected upstream of the gas inlet of the rotary compressor; check valve means connected in the high-pressure gas discharge conduit between the high-pressure gas receiver and the compressor discharge manifold for checking flow from the receiver back to the compressor; and an auxiliary suction pressure tank connected to the gas inlet downstream of the throttle valve means in the direction of gas flow through the throttle valve, the tank having an internal gas volume contiguous with the internal volumes of the throttle valve means, the gas inlet, the rotary compressor and the gas discharge path between the compressor and check valve means, said tank providing a static shutdown pressure at the gas inlet no greater than a preselected maximum pressure.

Claim 7

An automatic inlet pressure relieving apparatus for a rotary pneumatic compressor, said compressor having an inlet, a discharge manifold and a high-pressure gas discharge conduit connecting said discharge manifold to a high-pressure gas receiver, said pressure-relieving apparatus comprising: suction control throttle valve means connected upstream of the gas inlet of the rotary compressor; check valve means connected in the high-pressure gas discharge conduit between the high-pressure gas receiver and the compressor discharge manifold for checking flow from the receiver back to the compressor; and an auxiliary suction pressure tank connected to the gas inlet downstream of the throttle valve means in the direction of gas flow through the throttle valve, the tank having an internal gas volume contiguous with the internal volumes of the throttle valve means, the gas inlet, the rotary compressor and the gas discharge path between the compressor and check valve means, said tank providing a static shutdown pressure at the gas inlet no greater than a preselected maximum pressure.

Claim 8

The pressure-relieving apparatus of claim 5 further including: a pressure-bleeding conduit connected at one end to the high-pressure gas discharge between the rotary compressor and the check valve means and at the opposite end to the gas inlet of the compressor; and a shutoff valve positioned in the pressure-bleeding conduit between the ends of the conduit whereby the bleeding of the higher pressure discharge gas through the conduit to the compressor inlet can be shutoff.

Claim 9

A suction control inlet for a rotary air compressor having an inlet and discharge manifold means including a valve for inhibiting reversed flow of the compressed air comprising: an inlet conduit defining a passage for admitting a flow of ambient air; inlet check valve means located in the inlet conduit and oriented to transmit the airflow toward the rotary compressor and prEvent reverse flow through the inlet conduit; suction control means connected with the check valve means and responsive to the load on the compressor for regulating the inlet air pressure at the rotary compressor; auxiliary chamber means operatively connected between the suction control means and the rotary compressor, the chamber means having a chamber volume commensurate with the remaining air volume between the inlet check valve means and the flow inhibiting valve in the discharge manifold means whereby the volume of compressed air in the compressor and discharge manifold at shutdown will be expanded into the auxiliary chamber means volume and remaining volume at a pressure no greater than a prescribed maximum compressor-starting inlet pressure.

Claim 10

A suction control inlet for a rotary air compressor having an inlet and discharge manifold means including a valve for inhibiting reversed flow of the compressed air comprising: an inlet conduit defining a passage for admitting a flow of ambient air; inlet check valve means located in the inlet conduit and oriented to transmit the airflow toward the rotary compressor and prEvent reverse flow through the inlet conduit; suction control means connected with the check valve means and responsive to the load on the compressor for regulating the inlet air pressure at the rotary compressor; auxiliary chamber means operatively connected between the suction control means and the rotary compressor, the chamber means having a chamber volume commensurate with the remaining air volume between the inlet check valve means and the flow inhibiting valve in the discharge manifold means whereby the volume of compressed air in the compressor and discharge manifold at shutdown will be expanded into the auxiliary chamber means volume and remaining volume at a pressure no greater than a prescribed maximum compressor-starting inlet pressure.

Claim 11

The apparatus of claim 7 further including: an air filter positioned in the inlet conduit at a location upstream in the direction of inlet air flow from the inlet check valve means whereby the check valve means prevents back washing of the air filter.

Claim 12

The apparatus of claim 7 wherein: the auxiliary chamber means includes at least one tank connected to the compressor inlet downstream of the suction control means and having an internal volume calibrated for expansion of the volume of compressed air below the maximum compressor-starting inlet pressure.