Steam generator control

Claim 1

A controller unit comprising: first means for sensing temperature; a movable support arm, said first means including a second means for moving said movable support to a first position at a low reference temperature, to a second position at a predetermined second higher temperature, and to a third position at a predetermined third higher temperature; first pushbutton switch means for providing a first signal when positioned in said second position, said first switch means being mounted to said movable support arm; second pushbutton means for providing a second signal when moved to said third position; said second switch means being mounted to said movable support arm; a pressure-sensing element adapted to be mounted in a location to be monitored; third means adapted to move toward said first and second pushbutton switches in response to increases in pressure sensed by said pressure-sensing means; a first plunger resiliently mounted to said third means and aligned with the activating plunger of said first pushbutton switch; said first plunger including a restraining means for preventing said plunger from moving beyond the predetermined distance, whereby said first pushbutton switch is activated by a predetermined sensed temperature and a predetermined sensed pressure; a second plunger mounted in a line with the activating plunger of said second pushbutton switch; said third means being adapted to contact said second plunger and move it into contact with said activating plunger of said second pushbutton switch while said first plunger is restrained by said restraining means and said support means is in said first position, whereby the high value of pressure will activate the second pushbutton switch while said temperature sensing means senses a low temperature; said first and second pushbutton switches being adapted to provide first and second signals for monitoring purposes.