초록 ▼

A control system for operating a radiant furnace for curing ceramic products, the furnace having a furnace chamber, heating elements for applying radiant energy to the chamber, and movable platform means for supporting the ceramic product to be cured in the chamber. The control system generates a se

A control system for operating a radiant furnace for curing ceramic products, the furnace having a furnace chamber, heating elements for applying radiant energy to the chamber, and movable platform means for supporting the ceramic product to be cured in the chamber. The control system generates a sensor signal responsive to the furnace temperature which is algebraically added to an idle temperature signal, a maximum temperature signal and a ramp signal. The algebraic sum produces an error signal which is applied to a polarity detector for controlling the heating elements in response to a predetermined polarity. The polarity detector is strobed when the sensor signal reaches the maximum temperature signal. Prior to reaching idle temperature the energy to the heating elements is applied in controlled graduated incremental levels. The idle temperature condition is a variable independent of the maximum temperature setting. The control system is fully automatic with the movable platform and ramp signal being responsive to the idle temperature condition. The ramp output is enabled upon reaching the idle temperature level and upon detection of the movable platform at its top position.

대표청구항 ▼

A control system for operating a radiant furnace having a furnace chamber, heating elements for applying radiant energy to said chamber and movable platform means for supporting porcelain ceramic material to be cured at a controlled temperature level within said chamber; said control system comprisi

A control system for operating a radiant furnace having a furnace chamber, heating elements for applying radiant energy to said chamber and movable platform means for supporting porcelain ceramic material to be cured at a controlled temperature level within said chamber; said control system comprising: first presettable means for generating a low temperature control signal representative of a preselected low temperature setting; second presettable means for generating a high temperature control signal representative of a preselected high temperature setting; means for generating a sensor signal responsive to the furnace temperature in said chamber; ramp signal generating means for generating a linearly varying ramp output singal of predetermined slope; means responsive to said low temperature control signal and to the furnace temperature in said chamber for disabling said ramp signal generating means until the furnace temperature in said chamber is equal to said preselected low temperature setting; summing means for algebraically summing said low temperature control signal, said ramp output signal and said sensor signal to produce an error signal; polarity detector means responsive to said error signal for generating a heat control signal having a first logical level when said error signal is of a first polarity and having a second logical level when said error signal is of a second polarity opposite said first polarity; power supply circuit means responsive to said heat control signal for applying electrical energy to said heating elements when said heat control signal is at said first logical level; and means responsive to said high temperature control signal and said sensor signal for applying a strobe signal to said polarity detector means when said sensor signal reaches said high temperature setting so as to cause the logical level of said heat control signal to revert to said second logical level independent of said error signal.