Abstract: A refrigerated appliance that dispenses items includes a power source and a cooling system. Power control circuitry is electrically coupled between a power source (e.g., power cord coupled to a wall outlet) and components (for example, a compressor and one or more circulating fans of the cooling system) of the appliance. A controller, which is operably coupled to the power control circuitry, is adapted to manage the supply of electrical power to such components by intelligently transitioning between a normal-operation mode and at least one power-conserving mode. To achieve efficient power conservation, the controller automatically transitions between the at least one power-conserving mode and the normal-operation mode based upon at least one temperature signal, at least one dispensing event signal, and possibly other data signals supplied to the controller.

Abstract: An apparatus for (and method of) power-management control monitors operational characteristics (such as current, compressor relay control signals, internal temperature) of an appliance during an extended period of operation, and analyzes such operational characteristics to derive a characteristic cycle time of the cooling system of the appliance. The power input port of the appliance is automatically decoupled from a power source in response to control signals provided by sensor(s) and possibly in response to additional control signals. When a predetermined set of conditions are satisfied, the power input port of the appliance is automatically coupled to the power source after expiration of a shutdown time period, which is automatically adjusted by the power management control system based upon the characteristic cycle time of the cooling system and possibly other control signals (such as an ambient temperature level provided by a temperature sensor).

Abstract: A refrigerated soda vending machine includes sensors for monitoring various parameters such as temperature within its refrigerated chamber and for monitoring occupancy in the chamber vicinity. Sensor data is used to determine when to switch between normal and power-conservation modes of operation. In either mode, a cooling system is regulated so that a compressor goes on when an upper internal temperature threshold is reached and off when a lower internal temperature threshold is reached. In normal mode, fans circulate air to maintain a relatively uniform temperature throughout the chamber. During power-conservation mode, the fans are mostly off when the compressor is off. In the absence of circulation, the temperature within the refrigerated chamber stratifies so that a lower cool zone and an upper warm zone can be differentiated. Soda cans are held in vertical stacks so that the lowest cans are located in the cool zone.

Abstract: A refrigerated soda vending machine includes sensors for monitoring various parameters such as temperature within its refrigerated chamber and for monitoring occupancy in the chamber vicinity. Sensor data is used to determine when to switch between normal and power-conservation modes of operation. In either mode, a cooling system is regulated so that a compressor goes on when an upper internal temperature threshold is reached and off when a lower internal temperature threshold is reached. In normal mode, fans circulate air to maintain a relatively uniform temperature throughout the chamber. During power-conservation mode, the fans are mostly off when the compressor is off. In the absence of circulation, the temperature within the refrigerated chamber stratifies so that a lower cool zone and an upper warm zone can be differentiated. Soda cans are held in vertical stacks so that the lowest cans are located in the cool zone.

Abstract: A refrigerated soda vending machine includes sensors for monitoring various parameters such as temperature within its refrigerated chamber and for monitoring occupancy in the vicinity of the chamber. The sensor data is used to determine when to switch between a normal mode of operation and a power-conservation mode of operation. In either mode of operation, a cooling system is regulated so that a compressor goes on when an upper internal temperature threshold is reached and off when a lower internal temperature threshold is reached. In the normal mode of operating, fans circulate air within the chamber to maintain a relatively uniform temperature throughout the chamber. During power-conservation mode, the fans are off most of the time the compressor is off. In the absence of circulation, the temperature within the refrigerated chamber stratifies so that a lower cool zone and an upper warm zone can be differentiated. Soda cans are held in vertical stacks so that the lowest cans are located in the cool zone.

Abstract: An external power-management device controls the supply of electric power from a wall outlet to a refrigerated vending machine. The system includes a switch that couples power in an ON condition and decouples in an OFF condition. The switch is controlled by a controller based on data received from a current sensor, an occupancy sensor, a temperature sensor, and a time-of-year circuit. Upon startup, the current is monitored to determine maxima and minima for the vending machine. The system supplies power to the appliance during business hours as indicated by the time-of-year circuit and while the vicinity is occupied as determined by the occupancy sensor irrespective of the values for current and temperature. Absent the current sensor, the power would be decoupled after a predetermined duration of non-occupancy during nonbusiness hours.

Abstract: A power conservation system (PCS) includes a data handler, a controller and a power switch. The data handler is located between a host network and a network printer, while the power switch is between an AC power source and the printer's power input. The PCS can thus shut down the printer during periods when no data is being sent to the printer. The PCS monitors data to and from the printer, allowing it to track the printer's state and to capture its network identification. State tracking permits the PCS to emulate the printer when it is down and when it is booting. Additionally, the information stored in a state memory of the data handler can permit the printer's last ready state to be reconstructed after it turns on and boots to a ready state. In some cases, the data handler can answer network requests without turning on the printer. Thus, the PCS provides for effective power conservation while remaining invisible to a user.

Abstract: A phase-controlled power modulation system switches modes in response to circuit-threatening conditions to avert the necessity of a shutdown. Normal operation is in reverse phase control (RPC) mode. When an inductive load sensor detects the presence an inductive load, the system switches to a forward phase control (FPC) mode (FPC) to minimize voltage spikes that would otherwise result from the load's opposition to voltage transitions. When an overcurrent sensor detects an overcurrent, the system switches into an asymmetric hybrid mode (AHPC) to maximize delivered power while remaining within switch current handling capacity. In AHPC mode, an RPC component of a half-cycle waveform is cut off at the current limit, while an FPC component of the same half-cycle waveform is triggered after the source voltage drops to a confidence threshold below the current limit to ensure that current limiting is not triggered again during the same half-cycle.

Abstract: A method and circuit for reverse phase control of alternating current being delivered to a load are disclosed wherein voltage-controlled semiconductor switches, such as MOSFET's and IGBT's, are used as electronic switches to conduct voltage during the leading edge of the AC voltage cycle and conduction is terminated when the desired phase angle of the current flow has been reached. The disclosed method and circuit eliminate the need for zero crossing detection of the AC waveform and ensure that the voltage-controlled switches are always turned on before the zero crossing thereby minimizing radiated interference and incandescent lamp hum. The method used is primarily digital in nature making mechanical input or electronic input for the power control equally efficient to implement.