A temperature controller for a sorption system having an evaporator to produce a gas, a sorber containing a sorption material to sorb the gas during a sorption phase, a flow channel extending between the evaporator and sorber to provide a gas pathway connecting them, a valve to control the rate of gas flow in the flow channel, and a temperature sensor positioned to measure the temperature of an evaporator surface or the air adjacent thereto indicative of an evaporator surface temperature, and generate a temperature signal. The controller includes an inflatable member having first and second inflation states, and a control unit configured to evaluate the temperature signal and in response control the state of inflation of the inflatable member and thereby the operation of the valve to control the rate of gas flow between the evaporator and sorber through the gas pathway.

Versatile temperature control systems adaptable to many different applications employ different states and proportions of a pressurized dual phase medium in direct contact with a thermal load. In one aspect of the invention, thermal energy generated by pressurization of a gaseous medium is stored at a selected temperature level so that it is later readily accessible. In addition, in accordance with the invention temperature control of a two-phase medium can be exercised across selectable dynamic ranges and with different resolutions. In accordance with such features, the control can be exerted by varying the input flow rate of a mixture applied to a thermal load, or by controlling the back pressure of the flow through the thermal load. In accordance with another feature of the invention, substantial energy conservation can be effected by employing an ambient temperature evaporator configuration between the thermal load and the input to the compressor. This variant also utilizes the two-phase characteristics of the medium. Moreover, the system can be configured compactly utilizing a thermal reservoir for retaining thermal energy for special purposes. In a food processing system for providing a frozen product, for example, the thermal reservoir can be accessed to utilize the refrigerant itself in different operating modes, such as rapid heating and system cleansing. In the food processing application, target temperatures can be set and maintained on a platen which is to receive food ingredients using energy flows at two different enthalpies, to enable rapid freezing or temperature elevation.

A heating system for heat recovery from a liquid with an above-ambient temperature, which separates the heating process into a plurality of preheat stages. The heat pump includes an evaporator coupled to a heat generating apparatus via a first pump to transfer heat and preheat fluid flowing through a first heat exchanger to 31° C.-33° C. A sub-cooler pre-heats the incoming fluid as the second stage to 40° C.-45° C. using residual heat after the condensing step. A condenser coupled to a second heat exchanger heats the preheat fluid discharged from the first heat exchanger to 40° C.-45° C. The condenser is coupled to a storage tank to heat the preheat fluid discharged from the second heat exchanger to 58° C. to 85° C. Heat is transferred through the heat pump from the heat generating apparatus to maintain temperature of the fluid flowing through the second heat exchanger and fluid in the storage tank.

A temperature controller for a sorption system having an evaporator to produce a gas, a sorber containing a sorption material to sorb the gas during a sorption phase, a flow channel extending between the evaporator and sorber to provide a gas pathway connecting them, a valve to control the rate of gas flow in the flow channel, and a temperature sensor positioned to measure the temperature of an evaporator surface or the air adjacent thereto indicative of an evaporator surface temperature, and generate a temperature signal. The controller includes an inflatable member having first and second inflation states, and a control unit configured to evaluate the temperature signal and in response control the state of inflation of the inflatable member and thereby the operation of the valve to control the rate of gas flow between the evaporator and sorber through the gas pathway.

A defrosting device includes a heating unit filled with a working fluid and including an active heating part heated to a first temperature that can evaporate the working fluid, and a passive heating part positioned at a rear side of the active heating part and heated to a lower temperature than the first temperature. The defrosting device also includes a heat pipe disposed adjacent to an evaporator to transfer heat to the evaporator while circulating working fluid heated by the active heating part, the heat pipe including an entrance portion configured to receive working fluid evaporated by the active heating part, and a return portion connected adjacent to the passive heating part and configured to receive working fluid that has condensed after circulating through the heat pipe. Condensed working fluid received at the heating unit first passes through the passive heating part before being reheated at the active heating part.

A hydrodynamic heater pump may include a housing and a stator fixed relative to the housing. A rotor may be coaxially aligned with and positioned adjacent the stator. The rotor and the stator define an interior region of a hydrodynamic chamber operable for heating a fluid present within the interior region of the hydrodynamic chamber. The rotor may be attached to a drive shaft for concurrent rotation therewith. The rotor may be moved axially along an axis of rotation of the drive shaft between a pumping mode position and a heating mode position. The rotor may be located a first distance from the stator when arranged in the heating mode position and a second distance from the stator when arranged in the pumping mode position. The second distance may be greater than the first distance.

A system for controlling a capacity of a compressor includes a motor of the compressor including a main winding connected at a connection point to an auxiliary winding and a drive configured to control a speed of the motor. The system includes a first switch configured to selectively connect the main winding to either a first line voltage or a first output of the drive, a second switch configured to selectively connect the connection point to either a second line voltage or a second output of the drive, and a third switch configured to selectively connect the auxiliary winding to either a capacitor or a third output of the drive. The system includes a solenoid valve configured to selectively either operate in a first capacity or a second capacity. The system includes a control module configured to control the drive, the first switch, the second switch, and the third switch.

In order to reduce the effect on a compressor caused by foaming in an oil tank, a control unit for controlling an oil pump starts the oil pump before a compressor is started (SA1), starts the compressor (SA4) when an oil supply differential pressure P satisfies a compressor startup condition during a reference time Tas from the starting of the oil pump (“Yes” in SA3), and extends the operation of the oil pump for a prescribed time without starting the compressor (Step SA5) when the compressor startup condition is not satisfied (“No” in SA3).

To provide a defrost system capable of preferable defrosting and prevention of generation of icicles on a casing without installing a brine circuit. A defrost system includes a thermosiphon defrost circuit that is provided by being branched from a circulation line, in which, at the time of defrosting, a CO.sub.2 refrigerant staying inside a fin-tube heat exchanger repeats a two-phase change of a gaseous form and reliquefaction, and which forms a CO.sub.2 circulation path together with the fin-tube heat exchanger; electromagnetic opening/closing valves and that are closed at the time of defrosting and set the CO.sub.2 circulation path to a closed circuit; and a first electric heater arranged above the thermosiphon defrost circuit so as to be adjacent to the thermosiphon defrost circuit, and naturally circulates the CO.sub.2 refrigerant in the closed circuit at the time of defrosting.

The motor-driven compressor includes an electric motor, a housing, a compression portion, and an inverter device. The inverter device includes an inverter circuit, a current sensor, a coordinate converter, a speed controller, a current controller, a PWM controller, and a rotation angle estimator. The speed controller generates a d-axis current command value and a q-axis current command value such that a necessary torque to drive the electric motor occurs. The inverter device includes a heat-generating current command section that increases a temperature of the electric motor by changing the d-axis current command value and the q-axis current command value. The heat-generating current command section changes the d-axis current command value and the q-axis current command value so as to shift them in a direction in which a d-axis current value increases along a constant torque curve in a d-q coordinate system.