Actuator control system

Claim 2

A control system for controlling the operation of a valve, comprising: a. a double-acting valve actuator having first and second portions for receiving operating fluid and being movable between a first position and a second position in response to fluid in said first and second portions, respectively; b. a first fluid line connected to said first portion of said valve actuator for conveying fluid thereto; c. a second fluid line connected to said second portion of said valve actuator for conveying fluid thereto; d. single conduit means for supplying fluid under pressure to operate said valve actuator and also provide a control signal at a point thereof; e. reserve fluid means connected to said single conduit means for accumulating fluid under pressure from said single conduit means; f. control valve means having an opening position and a closing position, comprising:

Claim 3

an inlet port and an outlet port conveying fluid under pressure from said single conduit means to said first fluid line when said control valve means is in the opening position; 2. an inlet port and an outlet port conveying fluid under pressure from said reserve fluid means to said second fluid line when said control valve means is in the closing position; and 3. pressure operator means responsive to the control signal to move said control valve means from the opening position to the closing position; g. check valve means in said single conduit means interposed between said control signal point and said reserve fluid means; and h. said reserve fluid means being of a sufficient fluid capacity to provide for a plurality of successive movements of said actuator means between said first and second positions thereof without the addition of fluid thereto from said single conduit means.

Claim 4

an inlet port and an outlet port conveying fluid under pressure from said single conduit means to said first fluid line when said control valve means is in the opening position; 2. an inlet port and an outlet port conveying fluid under pressure from said reserve fluid means to said second fluid line when said control valve means is in the closing position; and 3. pressure operator means responsive to the control signal to move said control valve means from the opening position to the closing position; g. check valve means in said single conduit means interposed between said control signal point and said reserve fluid means; and h. said reserve fluid means being of a sufficient fluid capacity to provide for a plurality of successive movements of said actuator means between said first and second positions thereof without the addition of fluid thereto from said single conduit means.

Claim 5

The structure set forth in claim 1, wherein said control valve means includes: a. means for connecting said first fluid line with the atmosphere in response to the control signal for expelling fluid through said first fluid line from said first portion of said actuator; and b. means for connecting said second fluid line with the atmosphere in the absence of the control signal for expelling fluid from said second portion through said second fluid line.

Claim 6

The structure set forth in claim 2 further including test valve means for simulating the control signal from said conduit means whereby the operation of said control system may be tested.