Compact operator for gas control valves

A compact linear operator adapted for operative combination with a gas control having a valve, the operation of said valve being directly controlled at least partly by linear displacement effected by said operator, the operator comprising:

• support means adapted to be fixedly connected with said gas control, said support means including a bore extending therethrough;
• a displacement transmitting member having a displacement-receiving portion, a displacement-transmitting portion for operative association with the valve, and including an intermediate shaft extending through said support means bore and being axially displaceable relative to the support means for imparting linear displacement from said displacement-receiving portion to said displacement-transmitting portion;
• a cantilevered bimetallic actuator mounted at one end to said support means and adapted to deflect in response to an applied temperature for providing a source of displacement for operative connection to said displacement-transmitting member;
• electrical heater means adapted to controllably apply a temperature to said bimetallic actuator;
• displacement amplifier means operatively interposed between said bimetallic actuator and said displacement-receiving portion of said displacement transmitting member for amplifying the displacement of said bimetallic actuator for transmission to said displacement-transmitting member.

A modular operator adapted for operative combination with a combination gas control having a main diaphragm valve operated by a bleed line which includes a servo pressure regulator diaphragm, a pressure regulating spring having one end in operative engagement with the servo diaphragm, the combination gas control being contained within a casing having a threaded opening through a wall thereof and in register with the pressure regulating spring, the modular operator comprising:

• support means adapted for threaded coupling engagement with the control casing at the threaded opening therein, said support means including a bore extending therethrough;
• variably positionable spring seat means for operatively engaging the other end of said pressure regulating spring, said spring seat means including a shaft extending through said support means bore and being axially displaceable relative to the support means for applying a variable reference force to the servo diaphragm by said pressure regulating spring;
• a cantilevered bimetallic actuator mounted at one end to said support means and adapted to deflect in response to an applied temperature;
• electrical heater means adapted to controllably apply a temperature to said bimetallic actuator;
• said bimetallic actuator being operatively coupled to the shaft of said variably positionable spring seat means, thereby to vary the displacement of the spring seat means and thus the reference force on said servo diaphragm by said pressure regulating spring in response to said applied temperature;
• and
• means for adjustably presetting a maximum pressure limit, said maximum pressure limit means comprising a rigid radial projection extending from said spring seat means shaft and an adjustable stop member mounted to said support means and being positioned to engage said projection to limit displacement of said spring seat means shaft in one direction.

A modular operator adapted for operative combination with a combination gas control having a main diaphragm valve operated by a bleed line which includes a servo pressure regulator diaphragm, a pressure regulating spring having one end in operative engagement with the servo diaphragm, the combination gas control being contained within a casing having a threaded opening through a wall thereof and in register with the pressure regulating spring, the modular operator comprising:

• support means adapted for threaded coupling engagement with the control casing at the threaded opening therein, said support means including a bore extending therethrough;
• variably positionable spring seat means for operatively engaging the other end of said pressure regulating spring, said spring seat means including a shaft extending through said support means bore and being axially displaceable relative to the support means for applying a variable reference force to the servo diaphragm by said pressure regulating spring;
• a cantilevered bimetallic actuator mounted at one end to said support means and adapted to deflect in response to an applied temperature;
• electrical heater means adapted to controllably apply a temperature to said bimetallic actuator;
• said bimetallic actuator being operatively coupled to the shaft of said variably positionable spring seat means, thereby to vary the displacement of the spring seat means and thus the reference force on said servo diaphragm by said pressure regulating spring in response to said applied temperature;
• and
• means for adjustably presetting a minimum pressure limit comprising a separate, externally-threaded insert stop member threaded into the threaded opening in said control casing and positioned to limit axially outward displacement of said spring.