Apparatus for adjusting and indicating the operating curve of a weather-responsive heating regulator

Claim 1

A heat regulating unit for controlling the supply rate of a boiler fluid having a predetermined temperature in accordance with the outdoor temperature to in effect maintain a selected predetermined ratio between said temperatures, comprising, a casing, a coordinate system marked on said casing which represents the relationship between said outdoor temperature and said boiler fluid temperature, a pointer for said coordinate system which represents the characteristic operating curve for said relationship, electric bridge circuit means mounted partially in said casing having two branches for receiving temperature responsive variable resistance resistors for sensing the outdoor temperature and the boiler fluid temperature, first and second potentiometers for the other two branches of said bridge mounted in said casing, first and second slide members mounted for sliding movement in said casing, said pointer being pivotally mounted on said first slide member for translatory movement therewith and pivotal movement relative thereto, said first and second potentiometers having control means operably attached to said slide members with said first potentiometer being controlled in accordance with the indicated level of said pointer and said second potentiometer being controlled in accordance with the slope of said pointer, and means for adjustably positioning said slide members to move said pointer to a desired position which results in imparting desired settings to said potentiometers.