Abstract: A peak load control apparatus with operating mode selection for an electric heating system having a plurality of electric heating units arranged in two or more groups in different rooms is disclosed. When the current carried by the feeder line exceeds a predetermined value a peak load trigger or flip-flop which receives a signal proportional to the feeder current from a detector delivers a peak load signal to a first control circuit or monostable which cuts power to a first selected group of heating units for a predetermined period, and to a second time control circuit or monostable which cuts power to a second selected group of heating substantially at the end of the period during which power is cut off to the first group of heating units. The heating units are provided with programmable thermostats connected to operating mode selector switches which are connected to the feeder line.

Abstract: A method and apparatus for adhesively bonding together in edge abutting relationship two sheets of woven, felted or other textile such as carpet using a joining tape which includes electrically conductive-metal foil or wires and an integral layer of heat softenable adhesive. Electric current is passed through the foil or wires to thereby heat and soften the adhesive. A control circuit senses the voltage and current in the foil or wires and controls the current in accordance with an adjustable predetermined value to heat the adhesive to a temperature at which the adhesive becomes tacky. The control circuit maintains the adhesive in the tacky state while the abutting edges which overlap the tape are adjusted as required to form the desired join. The control circult is then adjusted to increase the current in the foil or wires to increase the temperature thereof and melt the adhesive so that it flows into the material of the sheets.

Abstract: A power control arrangement for controlling the power output of a resistive heating element of the type having a fast thermal response time and a highly variable resistance with temperature. The power control arrangement includes a plurality of operator selectable power settings and an electronic switching system responsive to operator selection of these settings to rapidly couple and decouple a power supply to the element. The switching action is selected to permit rapid heat up of the element without causing an unacceptable current to flow and to prevent excessive cooling of the element after it reaches operating temperatures during steady state operation.

Abstract: A full sized, heavy-duty X-ray film processor operating on 20 amps. of 120 volt power supply. The processor posesses a heater for its developer, another for its fixer, and several for its drying section. The machine switches the power between the heater for the developer solution and one of the heaters for the drying section to limit its current demand. The heater for the fixer solution and another of the dryer's heaters may also not operate simultaneously to further control the processor's total current demand. By limiting the current required for its operation, the heavy-duty processor, which can develop about 175 films of size 14 inches by 17 inches per hour, operates on no more than 20 amps. of the usual 120-volt house current. The processor's circuit also includes a cycling motor which effectively turns off most of the processor's current-using components for a majority of the time. The insertion of a film into the processor, however, turns on the required components for proper film processing.

Abstract: A cooking unit comprises at least two electric cooking plates, for example four such plates. Each plate can have a pair of electrical heating resistances. Power is supplied to each cooking plate via a switching unit, comprising a thermostat. Each thermostat switches on and off and is so arranged that when part or all of the power to one cooking plate is switched off power is supplied to another cooking plate connected downstream thereof.

Abstract: A control for a self-contained refrigeration system air conditioner unit having a heating and cooling operation. The control provides for defrosting the evaporator and for supplying supplemental heat under selected temperature conditions. A lack of heating capacity by the air conditioner in the heating operation when the outdoor temperature is below a predetermined temperature is supplemented by a first and second heater in combination with the air conditioner refrigeration system heating operation.

Abstract: A cooking oven having both microwave and electrical resistance heating means and which fully utilize the capabilities of a limited-capability power source to achieve the shortest possible cooking time. The oven has a microwave energy generating system which requires less than all of the available current when operated at its full rated power level, and an electrical resistance heating element which requires substantially all of the available current when operated at its full rated power level. The oven also has a means for at least successively energizing the microwave energy generating system and the electrical resistance heating element at their respective full rated power levels. Additionally, there is a means for energizing the electrical resistance heating element from the power source at a reduced power level when the microwave energy generating system is energized at its full rated power level.

Abstract: A system having two heaters, such as a photographic processor with a solution heater and a dryer heater, has proportional controllers for each of the heaters. A priority control co-ordinates operation of the two controllers to give full priority to one of the two heaters during warm up, and a reduced percentage for running conditions. The other heater is allowed to share the remaining available input power.

Abstract: A power demand limiting circuit is disclosed comprising air temperature control apparatus coupled with a municipal source of electric current through a thermo-responsive switch, through a meter having means for measuring maximum power demand for any period in a succession of periods of preselected duration, and through a timer programmed to cycle a timer switch at least once during each of the periods, whereby the air temperature control apparatus is rendered incapable of demanding power continuously throughout any of the metered periods.

Abstract: A temperature control system controls operation of two heaters, such as the solution heater and dryer heater of a photographic processor. First and second temperature detectors sense temperature and provide first and second detector signals, which are compared with first and second reference ramp signals by first and second comparators. The comparators produce first and second inhibit signals, which prevent power from being supplied to the first and second heaters, respectively. A priority circuit prevents power from being supplied to the second heater if the first heater is receiving power.

Abstract: The control system permits limiting the electrical demand of a distribution network to a desired maximum value by regulating the temperature of one or more thermal loads with heating or cooling elements; this system includes: means for measuring the instantaneous demand of the network; means for measuring the instantaneous temperature of each of the thermal loads; means for comparing the demand of the network to the desired maximum value; means for comparing the measured temperature to the desired temperature for each of the thermal loads; and means for disconnecting or for connecting in response to the information obtained by the comparison, a fraction of the elements which is proportional to the difference between the measured temperature and the desired temperature.

Abstract: An energy demand controller adaptable for a house or building having a plurality of heating zones and appliances. The energy demand controller includes a temperature sensor for each zone, a central controller receptive of all the temperatures from each zone for comparing the sensed temperature to a predetermined value, and a switch panel having solid state switches responsive to commands from the central controller for selectively delivering power from a power source to the heaters and appliances. When the zones require heating because of a first predetermined temperature difference between the sensed temperature and the desired temperature, then the heaters for the various zones are sequentially activated for a short predetermined time interval. When a greater temperature difference exists between the desired level and the sensed level in a particular zone, the heaters for that zone are activated full time.

Abstract: A vendor for hot and cold beverages having a hot water tank for supplying hot water for hot beverages (e.g., coffee, tea, soup, chocolate), an electrical heater for heating water in the tank, a carbonator for supplying carbonated water for cold carbonated beverages, a water pump for pumping water to the carbonator or for cold non-carbonated beverages, a refrigeration system including a compressor providing refrigeration for cooling the water for vending cold beverages, and a system for reducing the current drawn by the heater when there is a demand for heating water in the tank and the compressor or the pump is in operation, so as to maintain the current drawn by the vendor below a maximum current rating.

Abstract: Simplicity is the height of invention.In order to conserve energy when the thermostat turns air conditioning apparatus on, in the present invention apparatus is employed to automatically reduce energy input to, and also heat output from, illuminating apparatus in the area being air conditioned. This is feasible because, in many instances, increased illumination from the sun, during daylight hours, renders the need much less for illumination from lamps or artificial luminares. In other instances, turning off a few lamps in each office can avoid blackouts, brownouts, overloading of generators, and burning out of air conditioning apparatus and other electrical appliances.

Abstract: A system for lowering electrical energy peak demand while minimizing service disruption allows instantaneous dropping of a plurality of interruptible thermal storage devices with predictable reserve capacity. At the time the loads are dropped, a central computer establishes a plurality of permissible off-times for corresponding mutually exclusive groups of loads in similar installations based on characteristic projected energy consumption profiles predicted from past statistical history for the groups. At the end of each off-time interval, a central transmitter transmits reconnect signals to which the devices in the corresponding group are responsive. The groups of units are thus reconnected sequentially avoiding the possibility of generating a secondary peak by indiscriminate, simultaneous reconnection. The reconnection sequence is determined according to changing priorities which take into account the customer's needs at the time of disconnection.

Abstract: A control system for controlling energization of electrically operated heat generating apparatus included in a multizone electrical heating system. Each of the zones has at least two parallel connected heat generating stages. The second stage heat generating apparatus in any of the zones is prevented from being energized irrespective of the temperature level in the zone when the number of the first stages already activated in each of the zones is greater than a preselected fraction of the total of the first stages.