Abstract: The invention relates to a refrigeration machine, particularly a heat pump, comprising a closed circuit, which contains a coolant and in which an evaporator, a compressor, a condenser and an, in particular, electrically operated expansion valve are arranged one after the other. The refrigeration machine also comprises an overheating control unit for at least intermittently regulating the temperature of the coolant in the area of the compressor, particularly the compression final temperature. The invention also relates to a method for operating a refrigeration machine of the aforementioned type.

Abstract: The present invention relates to a method for the determination of the coefficient of performance of a refrigeration machine, in particular of a heat pump, which includes a closed circuit which has a refrigerant and in which an evaporator, a compressor, a condenser and an expansion valve are arranged. In the method, at least three temperatures of the refrigerant are determined using temperature sensors arranged in the circuit. Alternatively, at least two temperatures and at least one pressure of the refrigerant is determined using sensors arranged in the circuit. Enthalpies of the circuit are calculated from the determined refrigerant temperatures and refrigerant pressures and the heat output and the taken up electrical power of the refrigeration machine are calculated therefrom to determine the coefficient of performance of the refrigeration machine from the quotient of the calculated heat output and the calculated taken up electrical power.

Abstract: The invention relates to a control unit for a refrigeration or air conditioning device, comprising a main processor that is situated in a housing and that controls the temperature, fan and/or the defrosting process of a refrigeration or air conditioning device. Contact points for a co-processor, which is separate from the main processor and is suitable for controlling an electronic expansion valve, are located in said housing.

Abstract: The invention relates to a control unit for controlling the expansion valve of a refrigeration or air conditioning system, comprising a temperature sensor that is connected upstream of the expansion valve in the coolant circuit. If the control unit detects a decrease in temperature of the aforementioned temperature sensor, which is generally caused by the start of a defrosting process, it displaces the expansion valve into a static state, to protect said valve during the defrosting process.

Abstract: The invention relates to a refrigeration machine, particularly a heat pump, comprising a closed circuit, which contains a coolant and in which an evaporator, a compressor, a condenser and an, in particular, electrically operated expansion valve are arranged one after the other. The refrigeration machine also comprises an overheating control unit for at least intermittently regulating the temperature of the coolant in the area of the compressor, particularly the compression final temperature. The invention also relates to a method for operating a refrigeration machine of the aforementioned type.

Abstract: Valve arrangement, in particular as pulse width modulated expansion valve of a refrigeration system, comprising the following elements: a valve body (1) with a passage opening (5), an armature tube (2) which is inserted into one end of the passage opening (5), an armature (3) which can be moved back and forth in the armature tube (2), a stationary armature core (4) which is inserted into the outwardly lying end of the armature tube (2), a restoring element (22) which is active between the movable armature (3) and the stationary armature core (4), a closure element (18) which is carried by the movable armature (3) and which cooperates with a passage opening (17) for opening and closing the valve arrangement as well as comprising a magnetic coil for actuating the valve arrangement, with a ring space (19) being formed between the armature tube (2) and the movable armature (3), the opening cross-section of which is dimensioned in such a manner that the space (20) which is formed between the movable armature (3) a

Abstract: A valve arrangement is illustrated and described, in particular an electronic expansion valve arrangement, for pneumatic or hydraulic pressure media comprising a valve housing having a first medium connection and a second pressure medium connection, which are connected together by a throughflow space formed in a cavity of the housing, and a slider element which is arranged in the valve housing and cooperates with a valve seat, with the slider element being operationally connected to a positioning element of a drive and being displaceably guided parallel to the valve seat between a closed position, in which the one contact surface of the slider element closes a throughflow opening formed by the valve seat, and an open position, in which a throughflow passage formed in the slider element frees the throughflow opening.