JP2011162101A - Air conditioner for automobile and method of controlling operation of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner for an automobile in which the inside of a compressor is less damaged by monitoring the state of the outside air and a time for which the compressor is turned off so as to start, at low speed, the compression of a liquid refrigerant occurring when the compressor is turned off over a long period. <P>SOLUTION: When information from a temperature detection means 24 is Td°C or below and a time for which the compressor 11 is turned off is td sec. or longer, the compressor 11 is controlled so as not to be turned on until the result of the detection by a rotational speed detector 23 is equal to or less than Nd to gently start the compression of the liquid refrigerant accumulated in the compressor 11 for td sec. at a rotational speed of Nd or below. Consequently, the inside of the compressor is not damaged, and a high reliability can be provided to the air conditioner for an automobile. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an air conditioner for an automobile, and particularly relates to start-up control when liquid refrigerant is compressed in a compressor that may be generated while the vehicle is running.

  Conventionally, activation control at the time of compression of liquid refrigerant in a compressor in this type of automobile air conditioner relates to activation after the vehicle is stopped and left (see, for example, Patent Document 1).

  FIG. 4 shows a flowchart of the start-up control of the compressor of the conventional automobile air conditioner disclosed in Patent Document 1. This document makes various judgments about the start of the compressor after the engine is started, and finally discharges the liquid refrigerant accumulated in the compressor safely by starting the compressor at a predetermined reference speed or less. In addition, the liquid compression sound is prevented from being generated and the internal lock of the compressor is prevented by repeating the liquid compression start-up.

JP 2005-186785 A

  However, the conventional method can solve various problems in the compression of the liquid refrigerant that occurs immediately after the vehicle starts up, but it is compressed by normal air-conditioner control even when the vehicle is running, especially in low outdoor air such as in winter. The machine may turn off for a long time. In such a case, the liquid refrigerant may return to the compressor due to the temperature difference between the passenger compartment and the engine room and start up with the liquid refrigerant at the next startup. The machine has a problem that it may receive the same damage as the conventional example.

  The present invention solves the above-described conventional problems, and reduces damage to the compressor due to compression of the liquid refrigerant generated at the start of the compressor after being turned OFF for a long time, which may occur when the vehicle travels. It is an object of the present invention to provide a method for controlling an air conditioner for an automobile that does not affect the functions of internal parts of the machine.

  In order to solve the above-described conventional problems, an air conditioner for an automobile according to the present invention includes a compressor driven by rotational power of an engine, a condenser for condensing a high-temperature high-pressure refrigerant discharged from the compressor, and an expansion A refrigerating cycle system including a valve and an evaporator that evaporates the refrigerant expanded by the expansion valve, and a control unit that performs operation control of the refrigerating cycle system. The temperature, the number of revolutions of the engine, and the ON / OFF information of the compressor are input, and the control unit is in a case where the outside air temperature is equal to or lower than a predetermined temperature and the compressor is OFF for a predetermined period or more. In this case, control is performed so that the compressor is not started until the rotational speed of the engine becomes equal to or lower than a predetermined rotational speed.

  As a result, it is possible to suppress the compression of the liquid refrigerant generated by starting the compressor after the vehicle has been turned off for a long time during vehicle operation, and provide an air conditioner for an automobile that does not damage the compressor. It becomes possible to do.

  By these, it is possible to suppress the compression of the liquid refrigerant generated by starting the compressor after a long time OFF during vehicle operation, and provide an air conditioner for automobiles that does not damage the inside of the compressor It becomes possible to do.

  According to the configuration of the present invention, it becomes possible to suppress the compression of the liquid refrigerant generated by the start of the compressor after the vehicle has been turned off for a long time during operation of the vehicle, and does not damage the inside of the compressor. An apparatus can be provided.

The block diagram of the air conditioning apparatus which shows 1st embodiment of this invention. Control flow chart showing an embodiment of the present invention The block diagram of the air conditioning apparatus which shows 2nd embodiment of this invention Control flowchart showing a conventional embodiment

  1st invention evaporates the refrigerant | coolant expanded by the compressor driven by the rotational power of an engine, the condenser which condenses the high temperature / high pressure refrigerant | coolant discharged from the said compressor, the expansion valve, and the said expansion valve An automotive air conditioner comprising: a refrigeration cycle system including an evaporator; and a control unit that controls operation of the refrigeration cycle system, wherein the control unit includes an outside air temperature and the engine And the compressor ON / OFF information are input, and the control unit is configured to output the engine when the outside air temperature is equal to or lower than a predetermined temperature and the compressor is OFF for a predetermined period or longer. Control is performed so that the compressor is not started until the number of rotations becomes equal to or less than a predetermined number of rotations.

  As a result, it is possible to suppress the compression of the liquid refrigerant generated by starting the compressor after the vehicle has been turned off for a long time during vehicle operation, and provide an air conditioner for an automobile that does not damage the compressor. It becomes possible to do.

  In a second aspect based on the first aspect, the compressor ON / OFF information input to the control unit is based on a change amount per unit time of the temperature of the refrigerant discharged from the compressor. As a result, the compressor ON / OFF information can be obtained by a simple method.

  Further, the third invention is a compressor driven by the rotational power of the engine, a condenser for condensing the high-temperature and high-pressure refrigerant discharged from the compressor, an expansion valve, and a refrigerant expanded by the expansion valve. An operation control method for an automotive air conditioner comprising: an evaporator that evaporates; and a step of detecting an outside air temperature, and a step of detecting an OFF time of the compressor. Detecting the engine speed, and starting the compressor based on the outside air temperature, the OFF time of the compressor, and the engine speed. is there.

  As a result, it is possible to suppress the compression of the liquid refrigerant generated by starting the compressor after the vehicle has been turned off for a long time during vehicle operation, and provide an air conditioner for an automobile that does not damage the compressor. It becomes possible to do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 shows the overall configuration of an automotive air conditioner according to the present invention. The compressor 11 is driven by an engine 1 as a drive source through an electromagnetic clutch 11a by power transmission means including a pulley and a belt. The electromagnetic clutch 11a includes a pulley (not shown) driven by a belt, an armature (not shown) connected to the drive shaft of the compressor 11, and a magnet coil (not shown). The magnet coil is electrically connected to a control unit (control device 20). When the magnet coil is energized by an energization signal from the control device 20, the armature is attracted to the pulley and the output of the engine 1 is sent to the compressor 11. Transmitted and activated.

  Further, the rotation information of the engine 1 is electrically connected to the control device 20 by the rotation speed detecting means 23.

  Next, the condenser 12 is a heat exchanger that condenses the high-temperature and high-pressure refrigerant discharged from the compressor 11 by exchanging heat with the atmosphere using a condenser blower (not shown), and the refrigerant condensed by the condenser 12 is a receiver. The gas refrigerant is separated to store liquid refrigerant. The entire surface of the condenser is provided with temperature detecting means 24 for acquiring information on the current outside air temperature, and is electrically connected to the control device 20 for controlling the air conditioner.

  Finally, the expansion valve 14 is a valve that depressurizes the refrigerant that has flowed in by the receiver 13, and after the pressure is reduced, the refrigerant flows into the evaporator 15 to exchange heat with the air in the passenger compartment, thereby performing air conditioning in the vehicle.

  Next, the operation of the vehicle air conditioner configured as described above will be described with reference to FIG. In step 100, the information from the temperature detection means 24 is determined to determine whether the outside air state is low. Next, in step 110, the control device 20 determines whether or not the time during which the air conditioner is OFF is a predetermined period or more. Finally, in step 120, the engine speed immediately before the air conditioner returns is determined based on the information of the engine speed detector 23.

  Here, when the information of the temperature detection means 24 is Td ° C. or less and the OFF time is determined to be td seconds or more by a signal based on the activation information of the control device 20, the detection result of the rotation speed detection device 23 is Nd. Control is performed so that the compressor is not turned on until the following is reached. Note that when at least one of the signal from the temperature detection means 24 and the ON / OFF information of the compressor does not satisfy the above condition, the compressor 11 is restarted as usual.

  By configuring as described above, when the information of the temperature detection means 24 is Td ° C. or less and the OFF time is determined to be td seconds or more by a signal based on the activation information of the control device 20, the rotation speed is detected. Since the compressor is controlled not to be turned on until the detection result of the device 23 becomes Nd or less, the liquid refrigerant accumulated in the compressor 11 for td seconds starts gently at the rotation speed of Nd or less. Thus, it is possible to provide a highly reliable automobile air conditioner without damaging the inside of the compressor.

(Embodiment 2)
FIG. 3 is a block diagram of an air conditioner showing a second embodiment of the present invention. Although the configuration of each component is the same as that of the first embodiment shown in FIG. 1, a second temperature detection means 25 for detecting the temperature of refrigerant discharged from the compressor 11 is provided between the compressor 11 and the condenser 12. Is different. The second temperature detection means 25 is electrically connected to the control device 20.

By configuring as described above, the second temperature detection device 25 detects the temperature of the refrigerant discharged from the compressor 11. Therefore, if the information of the second temperature detection device 25 tends to increase per unit time. If the compressor 11 is in the ON state and has a downward tendency, it can be determined that the compressor 11 is in the OFF state. Therefore, the control device 20 can calculate the OFF time of the compressor 11 by determining the accumulated result. For this reason, the liquid refrigerant accumulated in the compressor 11 during the OFF time td seconds starts gently at a rotation speed of Nd or less, so that the compressor is not damaged and is highly reliable for automobiles. It becomes possible to provide the air conditioning apparatus.

  In order to determine the operation ON / OFF time of the compressor 11, the accumulated time of the OFF signal that the control device 20 outputs to the magnet coil may be detected.

  As described above, the automotive air conditioner according to the present invention reduces damage to the compressor due to the compression of the liquid refrigerant that occurs when the compressor is started after being turned off for a long time, which may occur when the vehicle travels. Therefore, the present invention can be applied to vehicles that are driven in various states.

DESCRIPTION OF SYMBOLS 11 Compressor 12 Condenser 13 Receiver 14 Expansion valve 15 Evaporator 20 Control apparatus 23 Rotational speed detection apparatus 24 Temperature detection apparatus

Claims (3)

A compressor driven by the rotational power of the engine, a condenser that condenses the high-temperature and high-pressure refrigerant discharged from the compressor, an expansion valve, and an evaporator that evaporates the refrigerant expanded by the expansion valve A refrigeration cycle system,
A control unit for controlling the operation of the refrigeration cycle system;
An air conditioner for automobiles comprising:
The control unit receives an outside air temperature, the engine speed, and ON / OFF information of the compressor.
When the outside air temperature is equal to or lower than a predetermined temperature and the compressor is OFF for a predetermined period or longer, the control unit controls the compressor until the engine speed becomes equal to or lower than a predetermined speed. An automotive air conditioner that is controlled so as not to start. The ON / OFF information of the compressor input to the control unit is obtained based on a change amount per unit time of the temperature of the refrigerant discharged from the compressor. Air conditioner for automobiles. A compressor driven by the rotational power of the engine, a condenser that condenses the high-temperature and high-pressure refrigerant discharged from the compressor, an expansion valve, and an evaporator that evaporates the refrigerant expanded by the expansion valve A refrigeration cycle system,
An operation control method for an automotive air conditioner comprising:
Detecting the outside air temperature;
Detecting an OFF time of the compressor;
Detecting the rotational speed of the engine;
Starting the compressor based on the outside air temperature, the OFF time of the compressor, and the engine speed;
Control method for an air conditioner for an automobile including

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