Abstract: A printed circuit board mounted rotary electrical switch has a rotatable electrical contact carrier mounted for rotation within a cup-shaped housing and carrying indexing and rotation limiting devices cooperating with the housing. An electrical contact strip is carried by the rotatable carrier for selectively providing a direct electrically conductive bridge between pairs of a plurality of projecting electrical contacts attached to the circuit board and to corresponding printed wiring on the circuit board. The housing is attached to the circuit board by screws threaded into the circuit board through perforated ears projecting from respective sides of the housing. The carrier and the housing are made of an electrically non-conductive material to protect the strip and the contacts from extraneous electrical paths.

Abstract: Disclosed is a fuel gas control for controlling the delivery of fuel gas. The present gas control comprises an inlet chamber having an inlet for receiving a supply of gas and an outlet chamber having an outlet for providing a supply of gas. The inlet and outlet chambers are connected by a valve opening. A valve is operatively associated with the opening. The valve has a closed position for preventing the flow of gas through the opening and an open position for permitting the flow of gas through the opening. The present control further comprises control chamber means for moving the valve between its open and closed positions in response to pressure variations within the control chamber means. The present control further comprises apparatus for directly connecting the control chamber means to a pressure signal from a power combustion air blower so that the valve is positioned in response to the pressure signal from the combustion air blower.

Abstract: A gas valve assembly has a safety valve and two controlled valves connected in series. A first of the controlled valves is electromatic and a second is a conventional pressure controlled valve. A control knob provides for manual control of the safety valve and for locking the first electromagnetically controlled valve in an off position. The manual control knob, when in the off and pilot positions, causes a stop member to be moved against the movable core member of the electromagnetic operator to hold the electromagnetic controlled valve in an off position.

Abstract: An electromagnetic relay having a dual acting armature has a U-shaped armature with two divergent legs. The armature is pivoted on one of the legs with the pivoted leg being arranged adjacent to an electromagnetic field producing structure including an electrically energizable coil. A first movable electrical contact carrying means is arranged to cooperate with a first one of the legs of the armature to produce a motion of a first electrical contact between a first and a second position in response to an energized and a non-energized state of the coil, respectively. Concurrently, a second movable electrical contact carrying means is arranged to cooperate with the other or second leg of the armature to produce a motion of a second electrical contact between a first and a second position in response to an energized and deenergized state of the coil, respectively. The coil is located in the bight of the U-shaped armature with the pivoted first leg being urged by a spring away from the coil.

Abstract: A differential temperature control uses a first temperature expansion element for driving a first pivoted lever supporting a selectively operable switch and a second temperature expansion element for driving a second pivoted lever for operating the switch. The position of the switch operating lever with respect to the switch is achieved by either the first or second temperature expansion element which move the first lever and the second lever, respectively, in direct proportion to a change in the corresponding sensed temperatures. In the case of a movement produced by the temperature expansion element controlling the position of the switch, a similar temperature change sensed by the second temperature element would be needed to "chase" the switch to restore a switch actuation relationship to produce a differential temperature control. A selective adjustment of the spacing of the second lever with respect to the switch is used to change the differential temperature that will produce a switch actuation.