Abstract: An electromagnetic clutch (1) of an air conditioning compressor (2), in particular for a motor vehicle (11), transmits a torque to a drive shaft (3) of the compressor (2) depending on an electric current (I) being fed to clutch coils (4) of the electromagnetic clutch (1) to generate an electromagnetic clutch force. According to a control method (10), a slippage of the electromagnetic clutch (1) is determined by a difference between the rpms of the electromagnetic clutch (1) and of the drive shaft (3), and is monitored by a slippage sensor (5). The electric current (I) and the resulting clutch force are adjusted dependent on slippage by a pulse width modulation controller (6) of the compressor (2). The pulse width modulation controller (6) is electrically connected to the clutch coils (4) and modulates a pulse width of the electric current (I) fed to the clutch coils (4).

Abstract: A variable-capacity compressor control valve is configured for easily regulating the opening degree of an in-valve release passage, and thus can effectively reduce internal circulation of refrigerant within the compressor and effectively improve the operation efficiency of the compressor. An in-valve large-opening release passage with a relatively large opening degree, which is used during the compressor actuation time, and an in-valve small-opening release passage with a relatively small opening degree, which is used during both the compressor actuation time and the normal control time (i.e., Pd?Pc control time), are formed using different passages.

Abstract: A variable-capacity compressor control valve is configured for easily regulating the opening degree of an in-valve release passage, and thus can effectively reduce internal circulation of refrigerant within the compressor and effectively improve the operation efficiency of the compressor. An in-valve large-opening release passage with a relatively large opening degree, which is used during the compressor actuation time, and an in-valve small-opening release passage with a relatively small opening degree, which is used during both the compressor actuation time and the normal control time (i.e., Pd?Pc control time), are formed using different passages.

Abstract: Provided is A displacement control valve which includes a valve housing, a valve element constituting a main valve that contacts and separates from a main valve seat, for opening and closing communication between discharge ports and control ports by driving force of a solenoid, a pressure-sensitive valve that opens and closes according to ambient pressure, and a pressure-sensitive valve member constituting the pressure-sensitive valve together with a pressure-sensitive element. The valve element and the pressure-sensitive valve member are formed with an intermediate communicating passage which allows communication between the control ports and the suction ports by opening and closing of the pressure-sensitive valve.

Abstract: Provided is A displacement control valve which includes a valve housing, a valve element constituting a main valve that contacts and separates from a main valve seat, for opening and closing communication between discharge ports and control ports by driving force of a solenoid, a pressure-sensitive valve that opens and closes according to ambient pressure, and a pressure-sensitive valve member constituting the pressure-sensitive valve together with a pressure-sensitive element. The valve element and the pressure-sensitive valve member are formed with an intermediate communicating passage which allows communication between the control ports and the suction ports by opening and closing of the pressure-sensitive valve.

Abstract: The subject invention provides a compressor assembly for an air conditioning system for a vehicle. The compressor assembly is of the variable displacement angle wobble plate type, and includes a housing that defines a suction cavity, a discharge cavity, and a crankcase. An electronic control valve controls the flow of a fluid between the discharge cavity and the crankcase for pressurizing the crankcase to de-stroke the compressor assembly. The control valve includes a pressure sensing member, which is responsive to a suction pressure to open fluid communication between the discharge cavity and the crankcase when the suction pressure is below a pre-determined set-point. The control valve also includes an actuator port in fluid communication with the discharge cavity for urging the member into the activated position to open fluid communication between the discharge cavity and the crankcase when the suction pressure is above the pre-determined set-point.

Abstract: An integrated capacity control valve for a variable capacity refrigerant compressor includes an integral pressure sensor that is continuously coupled to a discharge port of the valve for measuring the refrigerant discharge pressure. A plunger of the control valve is disposed within a passage coupling the compressor crankcase to the discharge port, and is positioned by pneumatic and electric control elements to regulate the refrigerant suction pressure. The plunger has intersecting axial and lateral bores that define a continuous passage between the discharge port and a cavity in which the pressure sensor is retained so that the sensor is continuously exposed to the discharge pressure regardless of the plunger position, and refrigerant discharge pressure in the lateral bore produces a bias force on the plunger that compensates the pneumatic suction pressure setpoint for a pressure drop between the evaporator and the suction port of the valve.

Abstract: A capacity control system for a variable capacity refrigerant compressor includes an internal bleed passage coupling a crankcase chamber of the compressor to a suction port, an electrically-operated two-port control valve that selectively opens and closes a passage between the crankcase chamber and a discharge chamber, and pressure sensors for measuring the compressor discharge pressure and suction pressure. A plunger of the control valve is disposed within the passage coupling the crankcase chamber and the discharge chamber, and a solenoid armature linearly positions the plunger within the passage to open and close the passage. The plunger has an axial bore that forms a continuous passage between the discharge chamber and a cavity in which the discharge pressure sensor is retained so that the sensor is continuously exposed to the discharge pressure regardless of the plunger position.

Abstract: A non-linear control method for an air conditioning system utilizes fuzzy logic to regulate the activation of a displacement control valve for a variable displacement compressor for maintaining a system parameter, such as the evaporator outlet pressure or temperature, at a desired value. The control inputs include the system parameter to be controlled and a refrigerant pressure that reflects changes in the compressor displacement.

Abstract: A non-linear control method for an air conditioning system utilizes fuzzy logic to regulate the activation a displacement control valve for a variable displacement compressor for maintaining a system parameter, such as the evaporator outlet pressure or temperature, at a desired value. The control inputs include the system parameter to be controlled and a refrigerant pressure that reflects changes in the compressor displacement.

Abstract: A capacity control system for a variable capacity refrigerant compressor includes an internal bleed passage coupling a crankcase chamber of the compressor to a suction port, an electrically-operated two-port control valve that selectively opens and closes a passage between the crankcase chamber and a discharge chamber, and at least one pressure sensor within the control valve that is continuously coupled to the discharge chamber for measuring the compressor discharge pressure. A plunger of the control valve is disposed within the passage coupling the crankcase chamber and the discharge chamber, and a solenoid armature linearly positions the plunger within the passage to open and close the passage. The plunger has an axial bore that forms a continuous passage between the discharge chamber and a cavity in which the pressure sensor is retained so that the sensor is continuously exposed to the discharge pressure regardless of the plunger position.

Abstract: In a method for the temperature regulation of an air conditioning system having a condenser, an evaporator, an expansion device and a compressor, the stroke of which can be set via a valve, the temperature in the region of the air outlet of the evaporator is measured and a desired temperature is set by a controlling of the valve. The temperature regulation additionally takes place in dependence on the refrigerant pressure.

Abstract: An improved control method for an electronically controlled variable displacement refrigerant compressor, where the control has normal and high speed displacement control modes, with smooth transitions between such control modes. The displacement control mechanism is in the form of a solenoid valve, and the valve is pulse-width-modulated (PWM) at a variable duty cycle to regulate displacement of the compressor. When the compressor is operating in a normal speed range, a first control mode determines a normal PWM duty cycle to satisfy cooling demand; when the compressor is operating in a high speed range, a second control mode determines an alternate PWM duty cycle based on compressor speed. The solenoid valve is operated in accordance with the duty cycle corresponding to the lower displacement. A smooth transition from the normal control mode to the high speed control mode is achieved by scheduling the alternate duty cycle as a function of compressor speed.