Abstract: A duty cycle controller for an air conditioning system. Solid state switches are connected in series with the heating and cooling switches of a thermostat in circuits for energizing the cooling and heating subsystems, respectively, of an air conditioner. A switch control circuit, when enabled, causes the solid state switches to be conductive when set and nonconductive when reset. Timing signals from a counter applied to the switch control circuit determine the state of the switch control circuit and thus the duty cycles for the heating and cooling subsystem. The controller is provided with a safety circuit which disables the switch control circuit to render the solid state switches nonconductive for a predetermined period of time after a power interruption or after a cooling or heating switch of the thermostat opens. The controller assures that each heating and cooling duty cycle begins with a full energization period. The length of the heating and cooling duty cycles can be readily varied.

Abstract: A method of regulating startup operation of a vapor compression refrigeration system to prevent oil pump cavitation during startup of the refrigeration system is disclosed. The method comprises monitoring the rate of decrease in evaporator pressure or temperature or monitoring compressor suction line pressure and then comparing this monitored rate to a rate of pressure or temperature decrease which is predetermined to prevent oil pump cavitation. If the monitored rate exceeds the predetermined rate control action is taken to adjust the capacity of the compressor to provide a desired rate of pressure drop which prevents oil pump cavitation. A microprocessor control system and a mechanical control system are disclosed for carrying out the disclosed method.

Abstract: A method and apparatus for controlling principle power consuming components such as compressors and fans for a refrigeration or air conditioning system so it will operate automatically with minimal energy consumption despite changing environmental and system conditions. The apparatus comprises a series of sensors to provide input data including the temperature from selected conditioned zones, valves for controlling coolant and refrigerant flow; switching devices for on-off control of the power components; and computing elements for receiving input data and constantly recomputing operating instructions for the power components that control their operation.

Abstract: A method for air conditioning for vehicles comprising a step of detecting a temperature of a passenger compartment of a vehicle, an atmospheric temperature and a preset temperature in the initial period of air conditioning, a step of judging the results of comparisons between said temperatures and a step of switching between air conditioning by the circulation of inside air and air conditioning by the introduction of outside air.

Abstract: A high speed freezing apparatus in use for a refrigerator. In the freezing apparatus, evaporators for the cold and freezing chambers are coupled in a series relation with respect to a compressor. An electromagnetic valve is provided in parallel with the evaporator for the cold chamber. When a high speed freezing start signal is produced from an operating section mounted on a front panel of a door for the freezing chamber, a timer circuit provided in a control section is operated. An operating condition of the compressor is detected by a detecting transformer and a given signal is produced from a start-failure preventing circuit. The start signal is transferred through a gate circuit to a relay portion only during the time that the given signal is transmitted to a gate circuit. Through the relay portion, the compressor and the electromagnetic valve are driven, so that the refrigerant is supplied to only the evaporator for the freezing chamber to start the high speed freezing operation.

Abstract: A programmable thermostat for use with air conditioners or heat pumps.Two (2) programmable timer-counters determine the respective amounts of time that the compressor will and will not operate. Both timers are consumer controlled. The "on" timer initiates compressor operation at the beginning of its cycle, and activates the "off" timer at the end of its cycle. The "off" timer stops compressor operation at the beginning of its cycle and activates the "on" timer at the end of its cycle.Operation of the "off" timer can be overridden by a "satisfied/not satisfied" means which re-starts the "on" timer at the end of its cycle if certain monitored conditions have not attained a preselected threshhold value.Filtering means are also provided so that the "on" timer responds only to genuine calls for service from the thermostat.

Abstract: A method and control system for operating a vapor compression refrigeration system to prevent oil pump cavitation during startup of the refrigeration system is disclosed. The control system includes a temperature or pressure sensor located in the evaporator of the refrigeration system, a microprocessor, and an inlet guide vane control mechanism. During startup, the pressure of the gaseous refrigerant or the temperature of the liquid refrigerant in the evaporator of the refrigeration system, or compressor suction line pressure, is measured and an electrical signal corresponding to the measured pressure or temperature is processed by the microprocessor to determine the actual rate of pulldown of refrigerant pressure in the evaporator. The microprocessor compares the actual pulldown rate to a pulldown rate which has been predetermined to prevent compressor oil pump cavitation.

Abstract: A refrigerator including a freezer compartment with a quick-chilling chamber having a first container section with a door for access to the interior of the container section from outside the freezer compartment and a second air-duct section. There is airflow communication between the first container section and freezer compartment, airflow communication between the second air-duct section and freezer compartment and airflow communication between the first and second sections near the top thereof. There is also provided means for moving air from the freezer compartment in a path through one section and the other section of the quick-chilling chamber and back into the freezer compartment for a selectable period of time. Thermal insulation is provided between the quick-chilling chamber and the freezer compartment.

Abstract: What is disclosed is a water heating system characterized by a remote hot water storage tank having water interconnections with a heat pump unit and a remote, timed water circulating pump and water circuit incorporating temperature sensor and thermostat. The heat pump unit is adapted to be employed at a location near a kitchen or laundry room and includes conventional constituents such as compressor, condenser, expansion device, and evaporator connected in a closed refrigerant circuit; blower for circulating air from conditioned space across the evaporator; and pump for circulating water past the hot refrigerant gas in the condenser. The condenser comprises a double-walled heat exchanger for preventing contamination between the respective fluids. The heat pump unit comprises a cabinet housing the same and having a warm air inlet adjacent its bottom and cool air outlet adjacent its top.

Abstract: An electric refrigerator with an automatic ice-making unit which comprises in combination a cooling unit including a compressor, a condenser and an evaporator with a refrigerating chamber and an auger type automatic ice-making unit with an ice-storing chamber.

Abstract: The process for freezing cell suspensions by locating the suspension in a freezing chamber and simultaneously monitoring the temperature of the suspended cells and of the chamber. The cooling of the chamber is regulated at predetermined rates in response to give temperature levels of the sample. The cooling chamber includes a fan, a heater, and a source of refrigerant. The process includes the steps of selectively decreasing and increasing the temperature of the freezing chamber responsive to predetermined temperature points on the freezing curve of the cell sample.

Abstract: A multistage timer control setback thermostat control system maintaining a normal temperature in a space and during selected time periods a reduced temperature wherein a first stage is a refrigeration heat pump, the operation of which is affected by outdoor temperature, and a second stage is an auxiliary electrical heating source. An outdoor temperature responsive means is connected in the control system to maintain the heat pump energized during the space temperature setback period if the outdoor temperature is below some predetermined value. Additionally, the indoor thermostat has a high limit temperature responsive means for terminating the operation of the heat pump should the space temperature exceed some predetermined value during the space temperature setback period.

Abstract: The present application discloses a control device for an ice making machine to make ice by circulating ice-making water to an ice making member having a refrigerating system, said control device comprising a timer circuit to be operated simultaneously with or with a delay after the start of an ice making operation and adapted to control a period of time during which an ice making operation is performed, a temperature sensing element whose impedance varies with the variations of the ambient temperature around the refrigerating system, so that an input voltage applied to the timer circuit may vary with the variations of an impedance of the temperature sensing element, thereby to automatically control the period of time during which an ice making operation is performed, whereby the thickness of ice made when one cycle of an ice making operation is completed, may be maintained constant at all times.

Abstract: An energy-saving device is disclosed which is particularly designed to control the temperature of the refrigerant in an air conditioning or refrigeration unit by evaporating a sprayed liquid on the refrigerant-containing vessels. The device may alternatively be utilized to introduce sprayed liquid into the heated air stream of a hot air furnace plenum to provide humidification. The device includes a temperature probe (24) which preferably comprises a thermistor that is positioned adjacent a control area where the temperature is desired to be monitored. A spray nozzle (38) causes a liquid to impinge upon the refrigerant-containing vessels, or to be evaporated in the hot air stream, to effect pre-cooling of the refrigerant prior to entering the condensing coil, or to effect evaporation of the water in the hot air stream to provide humidification.

Abstract: Method and apparatus are disclosed for controlling and selectively setting back the comfort condition, such as temperature, within a conditioned zone utilizing a system which includes both preferred and back-up conditioning means, the former exhibiting more favorable energy consumption characteristics than the latter. The system is operable in both a normal mode, and in an economy mode during which the comfort condition is permitted to degrade toward an economy level during a setback period of predetermined duration. Selective operation of the preferred and back-up conditioning means is effected in order to minimize energy consumption during both modes and especially during the time that the comfort condition is restored to the normal level from the economy level. In a preferred embodiment, the preferred conditioning means comprise an electrically operated heat pump of the vapor compression type and the back-up conditioning means comprise electrical resistance-type heating means.

Abstract: A control circuit for an ice making machine having an ice forming mold and a refrigeration system for controlling the operation of the refrigeration system so as to cause water to freeze in the mold during a freezing cycle and to effect release of ice from the mold during a harvest cycle, including a timing circuit that is adapted to vary the time period of the freeze cycle in accordance with the temperatures of the ambient air and/or inlet water and to vary the time period of the harvest cycle in accordance with the temperature of the ambient air. In addition, the control circuit is further adapted to control the operation of the condenser fan during the harvest cycle in accordance with the temperature of the condensing unit.

Abstract: A system wherein the pulses from a pulse source or the pulses divided or doubled in frequency are selected depending upon environmental conditions, and the number of selected pulses is counted so that an electronic counter generates the defrosting instruction.

Abstract: An automatic defrost system in which the actual defrost time of an evaporator coil, for example, is the controlling parameter for establishing a defrost cycle. The system automatically adjusts itself so that a predetermined amount of frost builds up in the frost accumulating period.

Abstract: A room air conditioner unit having juxtaposed main function switch means and auxiliary function switch means operative in a control circuit with an electric timer located in the unit's control area. The main function switch means has interlocked switches to operate a fan motor at low fan speed only, low fan speed cooling or high fan speed cooling while the auxiliary function switch means provides a plurality of manually actuable interlocked power-saver and timer switches such that a minimum of twelve different combinations of functions are achieved by the control circuit.

Abstract: A device for controlling a single variable capacity compressor, or multiple variable capacity compressors in either parallel flow or series flow chilling systems, senses temperature and load conditions and uses feedback in conjunction with synchronously and asynchronously timed logic circuitry to automatically control loading, unloading and sequencing of the compressor or compressors in the system in selected increments, thereby yielding a significant reduction in energy consumption as well as increased precision in maintaining a desired chill temperature. Additional circuitry provides for remote manual control as well as safety shut-off and failure indication. Alternative embodiments using solid state logic, including a microprocessor embodiment, are also disclosed.

Abstract: A snap-action camming means for use in controlling a double throw electrical switch. The switch may be biased to a first condition and substantially instantaneously thrown to a second operating condition by a spring associated with the cam. A single cam and cam follower are utilized to provide substantially positive throwing of the switch in both directions so as to avoid a dead break condition wherein the switch is maintained in an intermediate position between the two operating conditions. In one embodiment, the spring is formed integrally with the cam. The spring may be arranged to position the cam follower suitably to be maintained by subsequent engagement thereby with a portion of the cam.

Abstract: A control means for regulating the operation of a system for controlling the temperature within an enclosure so that a desired temperature within the enclosure is attained at a predetermined time wherein the switch on time of a thermal conditioning apparatus for the enclosure is increasingly delayed as the temperature outside the enclosure changes towards the desired temperature, so as to avoid the thermal conditioning apparatus being switched on earlier than necessary before said predetermined time.

Abstract: When the ambient temperature is high, proper temperature control is assisted within the poultry house using a spray means that sprays water onto a filter pad that is positioned in front of the fresh air inlet. The water spray and pad act to cool air being taken into the building through the inlet without objectionably raising the humidity.