JPH07304325A - Air-conditioning system for vehicle - Google Patents

Abstract

PURPOSE:To increase reliability of the control of turning on/off of electricity even in the case where a switch means provided with mechanical contact is used as a switch means for turning on/off an electric heater. CONSTITUTION:An inverter 21 generates three-phase AC voltage of variable voltage and variable frequency by switching output of a battery mounted on a vehicle. A three-phase AC motor 16a for driving a refrigerant compressor for refrigerating cycle is driven by output of the inverter 21 in such a way that its speed is changed so that capacity of the refrigerant compressor can be adjusted. Three PTC heaters 15 heat air blown by a blower in the condition in which electricity is conducted. Relay switches 26R, 26S, 26T are switched into either of the condition in which output of the inverter 21 is supplied to the AC motor 16a and the condition in which electricity is conducted to the PTC heaters 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner which uses a motor as a drive source of a refrigerant compressor in a refrigeration cycle, and more particularly to a vehicle air conditioner suitable for an electric vehicle.

[0002]

2. Description of the Related Art Conventionally, an air conditioner for an electric vehicle is provided with a refrigerating cycle including a hermetic refrigerant compressor having an AC motor built therein, and an inverter device for converting the output of a vehicle battery into AC power. Is provided, and the motor is driven by the inverter device. According to such a configuration, since the refrigerant compressor motor can be driven at a variable speed by changing the output frequency of the inverter device, the refrigerant discharge amount from the refrigerant compressor, that is, the heat exchange capacity by the refrigeration cycle can be easily performed. There are advantages such as controllability.

In the case of such an electric vehicle air conditioner,
An electric heater, PTC, is used as the heating source during heating operation.
It is common to use heaters. That is, the refrigeration cycle is a cooling operation (a concept that includes dehumidification operation)
In the case of exclusive use, the PTC heater is installed as a main heating source during heating operation or dehumidifying heating operation, and the refrigeration cycle has a configuration capable of forming a heat pump cycle for heating operation. In this case, the PTC heater is installed as an auxiliary heating source.

[0004]

In the above-mentioned conventional air conditioner for an electric vehicle, it is usual that the power source of the PTC heater is directly obtained from the on-vehicle battery. A relay has been used as a switch means for this. In this case, when a relay having a mechanical contact is used because a relatively large amount of direct current is interrupted by the relay, damage to the contact due to the arc when the contact is opened and the contact welding accompanying this There is a situation in which serious problems such as the above are likely to be caused and the operation reliability related to the on / off control of the PTC heater is deteriorated. Therefore, conventionally, a so-called solid state relay has been used for controlling the on / off of the PTC heater, but the solid state relay is more expensive than the mechanical relay, so that the cost of the entire device is reduced. There was a problem of rising prices. Further, such a problem similarly occurs when an antifogging heater for heating the windshield of an automobile is provided.

In particular, when using a PTC heater,
Since a DC voltage is continuously applied to the PTC heater, the metal forming the electrode of the PTC heater is deposited on the ceramic semiconductor portion forming the PTC heater by a kind of electrolysis, and the impedance between the electrodes is increased. There is also a possibility that a phenomenon (so-called migration) that causes a decrease in power consumption and a short-circuit accident accompanying this may occur, resulting in poor operational reliability during long-term use.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a mechanical device as a switch means for turning on and off an electric heater used as a heating source for a predetermined portion of a vehicle. To provide a vehicle air conditioner that has the effect of increasing the reliability of the on / off control even when using a switch unit having a fixed contact, and reducing the overall cost. is there.

[0007]

In order to achieve the above-mentioned object, the present invention comprises a refrigeration cycle for air-conditioning operation, the power source of a motor for a refrigerant compressor in the refrigeration cycle and the output of an on-vehicle battery are exchanged. In a vehicle air conditioner obtained from an inverter device for converting to electric power, an electric heater provided as a heating source for a predetermined portion of the vehicle,
A switch means for selectively supplying the output of the inverter device to the electric heater is provided (Claim 1).

The electric heater can be a heater for heating operation for heating the atmosphere in the vehicle compartment (claim 2). In this case, the electric heater is the main heater for heating operation. After being provided as a heating source, the switch means may be configured to disconnect the refrigerant compressor motor from the inverter device when the output of the inverter device is switched to a state of supplying the electric heater to the electric heater (claim) Item 3).

Further, the refrigeration cycle has a structure capable of forming a heat pump cycle for heating operation, and the switch means outputs the output of the inverter device when the heating capacity of the refrigeration cycle is insufficient. The refrigerant compressor motor and the electric heater may both be supplied (claim 4).

The electric heater may be an antifogging heater for heating a window glass for a vehicle (claim 5).

Further, the inverter device is configured to generate a multi-phase AC output, and a plurality of electric heaters to which inter-phase voltages of the multi-phase AC output by the inverter device are applied, and the electric heaters. A plurality of switch means corresponding to the heater may be provided (claim 6).

[0012]

In the vehicle air conditioner according to the present invention, the output of the vehicle-mounted battery is converted into AC power by the inverter device, and the converted output drives the motor for the refrigerant compressor in the refrigeration cycle. Also, for an electric heater provided as a heating source for a predetermined part of the vehicle,
The converted output from the inverter device is selectively supplied through the switch means. In this case, since the switch means for connecting and disconnecting the electric heater interrupts the alternating current, even when the switch means is provided with a mechanical contact, the arc is generated when the contact is opened. Contact damage will be reduced compared to when intermittent DC current is applied. As a result, it is possible to use low-cost switch means provided with mechanical contacts.

In the vehicle air conditioner according to the second aspect, the conversion output of the inverter device is selectively supplied to the electric heater through the switch means during the heating operation to heat the atmosphere in the vehicle compartment. . A PTC heater is generally used as an electric heater for such a heating operation, but since an AC voltage is applied to the electric heater, a PTC heater is used as the electric heater.
Even when the TC heater is used, there is no risk of the migration phenomenon as in the conventional configuration, and the operation reliability during long-term use is improved.

In the vehicle air conditioner according to the third aspect, during the heating operation, the refrigerant compressor motor is disconnected from the inverter device by the switch means, and in this state, the output of the inverter device is provided as the main heating source. It will be given to the electric heater. Therefore, since the output change of the inverter device is directly linked to the output change of the electric heater, the heating capacity of the electric heater can be easily adjusted.

In the vehicle air conditioner of the fourth aspect, the heating operation is performed by the refrigeration cycle functioning as a heat pump cycle. When the heating capacity at this time is insufficient, the switch means outputs the output of the inverter device. In addition to the motor for the refrigerant compressor for the refrigeration cycle, the electric heater is also applied, and the heat generated by the electric heater is accompanied by the elimination or supplement of the insufficient heating capacity. In this case, the switch means may have a simple structure in which the electric heater is brought into contact with and separated from the output side of the inverter device, and further, the current flowing in the electric heater provided as an auxiliary heating source (that is, the electric heater is (Less current than when used as the main heating source)
Since it is only necessary to connect and disconnect the switch, the structure can be simplified and the contact capacitance can be reduced, the cost of the switch means can be further reduced, and the contact damage due to the arc can be reduced.

In a vehicle air conditioner according to a fifth aspect of the present invention, in the case of performing an anti-fogging operation for windshields (which is a concept that also includes a removal operation for removing already fogged fogging), an inverter device is provided for the electric heater. The converted output by the switch is selectively supplied through the switch means to heat the window glass, and thereby the anti-fog operation of the window glass is performed.

According to another aspect of the vehicle air conditioner of the present invention, the inverter device is adapted to generate a multi-phase AC output, and when a predetermined portion of the vehicle is heated, the inter-phase voltage of the multi-phase AC output is plural. It is applied to a plurality of electric heaters through the switch means. In this case, it is possible to reduce the amount of current flowing through each electric heater, so that it is possible to reduce the contact capacity of the switch means and to be less likely to be damaged by the arc.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment in which the present invention is applied to an air conditioner for an electric vehicle will be described below with reference to FIGS. FIG. 3 schematically shows a ventilation system of an air conditioner for an electric vehicle. In FIG. 3, the air duct 1
Has an inside air introduction port 3 and an outside air introduction port 4 that are opened and closed by an inside / outside air switching damper 2 at the uppermost stream, and each of the outlets (defroster outlets) opened in the vehicle compartment is located on the downstream side. 5, branch ducts 9 to 12 for guiding the conditioned air are respectively connected to the center face outlet 6, the pair of left and right side face outlets 7, and the foot outlet 8).

Of the respective branch ducts 9 to 12, the upstream openings of the branch ducts 9, 10 and 12 are means for adjusting the ratio of the amount of air flowing into the branch ducts 9, 10 and 12, for example. Plate-shaped outlet dampers 9a, 10a and 12a are provided. Further, on the most downstream side of the branch ducts 10 and 11, the corresponding center face outlet 6 is provided.
Further, for example, plate-shaped opening / closing dampers 10b and 11a, which are means for opening / closing the side face outlet 7, are provided.

In the air duct 1, a blower 13 which is a blowing means is provided at a position corresponding to the inside air introducing port 3 and the outside air introducing port 4, and a cooling means such as a refrigerating cycle evaporating device is provided on the downstream side thereof. The container 14 is arranged. Further, on the downstream side of the evaporator 14 in the air duct 1, for example, three PTC heaters 15 (corresponding to an electric heater in the present invention) are arranged. In this case, the PTC heater 15 is provided as a main heating source for heating the air blown by the blower 13 and thus the vehicle interior atmosphere during the heating operation. Although not shown, each PTC heater 15 is configured by sandwiching a ceramic semiconductor having a positive temperature resistance characteristic between a pair of electrodes, and has a large number for increasing the heat exchange capacity of the blower 13 with the blown air. The heat radiation fin is provided.

FIG. 4 shows a piping configuration of a refrigeration cycle for air conditioning operation including the evaporator 14 together with a part of a ventilation system related to the evaporator 14. In FIG. 4, the refrigerant compressor 16 is a three-phase AC motor 1
6a (corresponding to the motor for refrigerant compressor in the present invention) is built in a hermetically sealed type, and the refrigerant discharge amount changes as the AC motor 16a is operated at a variable speed by an inverter device described later. It is composed. In this case, the high-temperature and high-pressure vaporized refrigerant discharged from the refrigerant compressor 16 is the outdoor heat exchanger 17 provided with the heat dissipation fan device 17a.
Further, the heat is liquefied through the decompression device 18 (an example of a capillary tube is shown in the figure, but it may be an expansion valve or the like), and then it is supplied to the evaporator 14.
A cycle is formed in which the gas is vaporized in 4 and then returned to the compressor 16 via the accumulator 19. The outdoor heat exchanger 17 functions as a refrigerant condenser in the case of the present embodiment. Further, the refrigerant compressor 16 is housed in the unit case together with the accumulator 19,
It is configured as a compressor unit 20.

FIG. 2 schematically shows an electrical configuration of an air conditioner for an electric vehicle. In FIG. 2, the inverter device 21 receives the output of the vehicle-mounted battery 22 via the fuse 23 and the power switch 24 that also serves as a blower switch, for example. AC motor 16 for refrigerant compressor 16 with three-phase AC output of voltage and variable frequency
a is driven at a variable speed. The inverter device 21 may be of any type as long as it can drive the three-phase AC motor 16a at a variable speed, but here, for example, a three-phase PWM inverter is used and its output torque is controlled. Constant voltage / frequency control (so-called V /
This is performed by open loop control using f control).

The operation control of the inverter device 21 is performed by E
It is performed by a control device 25 configured by a CU (Electronic Control Unit), and the control device 25 includes a C for detecting an input current of the inverter device 21.
The detection output from the current sensor 26 formed of T or the like is given. In this case, the control device 25
Is configured to perform an overcurrent protection operation of, for example, forcibly stopping the operation of the inverter device 21 when the current detected by the current sensor 26 exceeds a preset upper limit level.

Here, in FIG. 2, the output of the inverter device 21 is shown to be supplied only to the AC motor 16a, but actually, as shown in FIG. 1, the output of the inverter device 21 is controlled. It can also be supplied to the three PTC heaters 15 via relay switches 26R, 26S, and 26T that are simultaneously switched and controlled by the device 25. In this case, the relay switches 26R, 26S, and 26T are provided with mechanical transfer contacts, and the state in which the three-phase AC output voltage from the inverter device 21 is applied to the AC motor 16a and the phase between the three-phase AC outputs are applied. The voltage is applied to the three PTC heaters 15 connected in a delta connection. Therefore, the PTC heater 15 is disconnected from the inverter device 21 in the energized state of the AC motor 16a (the operating state of the refrigerant compressor 16), and the AC motor 16 is in the energized state of the PTC heater 15.
a is to be separated from the inverter device 21.

Returning to FIG. 2, the control device 25 has an operation signal (temperature setting signal, blown air volume setting signal, operation mode switching signal, ventilation mode switching signal, internal air circulation / outside air introduction mode switching signal) from the control panel 27. Etc.), a refrigerant temperature detection signal from a discharge temperature thermistor 28 for detecting the temperature of the refrigerant discharged from the refrigerant compressor 16, an outside air temperature detection signal from an outdoor temperature thermistor 29 for detecting the temperature outside the vehicle compartment, For example, a pressure detection signal from the pressure sensor 30 for detecting the refrigerant pressure upstream of the decompression device 18 is given.

The control device 25 is designed to be operated with the power switch 24 turned on, and in that operating condition, the blower 13 is driven at a speed according to the blown air volume setting signal from the control panel 27. It is like this. Further, in the above operating state, the control device 25 controls the output of the inverter device 21, the operation control of the heat radiation fan device 17a, and the relays 26R, 26S, 26T of the PTC heater 15 based on the input signals as described above.
It is configured to perform on / off control through the power supply, the inside / outside air switching damper 2, the outlet dampers 9a, 10a and 12a, and the opening / closing dampers 10b and 11a for controlling the operation of the servo motor 31 group. There is.

The main control contents by the control device 25 as described above are as listed below. (1) Judgment which one of the cooling mode and the heating mode is selected based on the operation mode switching signal from the control panel 27, and when the cooling mode is selected, the relay switch relays 26R, 26S and 26T are switched to alternating current. By switching to the motor 16a side, the inverter device 21
Is supplied to the AC motor 16a. As a result, the refrigerant compressor 16 is driven and the liquefied refrigerant is supplied to the evaporator 14, so that the air blown by the blower 13 is cooled by the evaporator 14. still,
In this case, the output frequency of the inverter device 21 is controlled to be higher as the temperature value indicated by the temperature setting signal from the control panel 27 is lower (in this case, V / f control is performed. , Its output voltage will also rise). As a result, the lower the set temperature, the higher the rotational speed of the AC electric motor 16a, and the refrigerant compressor 1
Since the refrigerant discharge amount from 6 increases, the cooling capacity increases.

(2) When the heating mode is selected,
Relay switch relay 26R, 26S, 26T PTC
By switching to the heater 15 side, the inverter device 2
The output of 1 is supplied to the PTC heater 15. As a result, the PTC heater 15 generates heat, and the air blown by the blower 13 is heated by the PTC heater 15. In this case, the three-phase AC output voltage from the inverter device 21 is 2π with respect to the three PTC heaters 15.
It will be applied with a phase difference of / 3. In addition, the output voltage of the inverter device 21 is controlled by the control panel 27.
The output of the PTC heater 15 may be controlled by changing it according to the temperature value indicated by the temperature setting signal from.

(3) The inside / outside air switching damper 2 is controlled through the servo motor 31 so as to be in a position according to the inside air circulation / outside air introduction mode switching signal from the control panel 27, and the outlet dampers 9a, 10a and 12a are also provided.
Is controlled through the servo motor 31 so as to be in a position according to the blow mode switching signal from the control panel 27.

(4) When the discharge refrigerant temperature from the refrigerant compressor 16 indicated by the refrigerant temperature detection signal from the discharge temperature thermistor 28 exceeds a preset upper limit temperature,
By reducing the output frequency of the inverter device 21 in order to protect the AC motor 16a, an abnormal rise in the refrigerant temperature is suppressed.

(5) The outdoor temperature thermistor 29 switches the capacity of the heat radiation fan unit 17a based on the outdoor temperature indicated by the outdoor temperature detection signal. In particular,
In the state where the cooling mode is selected, when the outside temperature of the vehicle indicated by the outside air temperature detection signal rises to, for example, 25 ° C. or more, the air blowing amount of the heat radiating fan device 17a is increased to condense the outdoor heat exchanger 17. The differential control is performed so that when the outside temperature of the vehicle is lowered to, for example, 22 ° C. or lower, the amount of air blown by the heat radiation fan device 17a is reduced to reduce the condensation capacity of the outdoor heat exchanger 17. still,
When the configuration for performing the heating operation using the heat pump cycle is adopted, the vehicle outside temperature indicated by the outside air temperature detection signal from the outside temperature thermistor 29 is lowered to, for example, 12 ° C. or less during the heating operation. At times, the amount of air blown by the heat dissipation fan device 17a is increased to increase the condensation capacity of the outdoor heat exchanger 17 (that is, the heat absorption amount of the heat pump cycle), and the heat dissipation fan is raised when the outside temperature of the vehicle rises to, for example, 16 ° C or more. A configuration is adopted in which differential control is performed in which the amount of air blown by the device 17a is reduced to reduce the condensation capacity of the outdoor heat exchanger 17.

(6) The refrigerant pressure upstream of the pressure reducing device 18 indicated by the pressure detection signal from the pressure sensor 30 (which can be regarded as equivalent to the refrigerant pressure in the outdoor heat exchanger 17) is
When the preset upper limit pressure is exceeded, the output frequency of the inverter device 21 is reduced to suppress the abnormal increase in the refrigerant pressure.

According to the configuration of this embodiment described above, the AC output from the inverter device 21 is given to the PTC heater 15 during the heating operation. Therefore, in the PTC heater 15, there is no fear that a migration phenomenon due to the application of the DC voltage will occur, and the operation reliability during long-term use will be improved.

Further, since the relay switches 26R, 26S and 26T for connecting and disconnecting the PTC heater 15 are to interrupt the alternating current, when the contact damage due to the arc when the contact is opened interrupts the direct current. It will be reduced compared to. As a result, the relay switches 26R, 26R
Even if a low-cost switch means having mechanical contacts such as S and 26T is used, there is no problem and the overall cost can be reduced. In this case, since the three interphase voltages of the three-phase AC output from the inverter device 21 are applied to the three PTC heaters 15, the current flowing through each PTC heater 15 becomes small. As a result, the relay switches 26R, 26S, 26T can be made smaller in contact capacity, and the relay switches 26R, 26S, 26T are less likely to be damaged by the arc, so that the cost can be reduced and the reliability for long-term use can be improved. Become.

Moreover, during the heating operation, the AC motor 16a for the refrigerant compressor 16 is disconnected from the inverter device 21, and the output of the inverter device 21 is given to the PTC heater 15 in this state. The output change of the device 21 is directly linked to the output change of the PTC heater 15. Therefore, the heating capacity of the PTC heater 15 can be easily adjusted by changing the output voltage of the inverter.

In the first embodiment described above, three PTs are used.
Although the C heaters 15 are used in a delta connection, they may be used in a star connection (Y connection) with three PTC heaters 15 as shown in FIG. 5 showing the second embodiment of the present invention.

FIGS. 6 to 9 show a third embodiment of the present invention, and only the parts different from the first embodiment will be described below. That is, in the third embodiment, as the refrigeration cycle for the air conditioning operation, one capable of forming a heat pump cycle for the heating operation is used, and the PTC heater 15 is auxiliary heated when the heating capacity by the refrigeration cycle is insufficient. It is characterized in that it is used as a source.

Specifically, in the blower system of the electric vehicle air conditioner shown in FIG. 8, the PT in the air duct 1
Upstream position of the C heater 15 (downstream position of the evaporator 14)
An auxiliary heat exchanger 32, which functions as a refrigerant condenser during the formation of the heat pump cycle and is used as a heat generation source during the heating operation, is arranged in the.

Further, in the refrigeration cycle piping configuration shown in FIG. 9, the refrigerant compressor 16 is housed in the unit case together with the accumulator 19 and the four-way valve 33 constituting the flow path switching means, so that the compressor unit 20 '. Is configured as. The four-way valve 33 is used for the refrigerant compressor 16
The refrigerant discharged from the refrigerant is switched between a first state in which the refrigerant is discharged to the outdoor heat exchanger 17 via the check valve 34 and a second state in which the refrigerant is discharged to the auxiliary heat exchanger 32. . When the four-way valve 33 is switched to the first state, the branch point 19a upstream of the accumulator 19 is communicated with the auxiliary heat exchanger 32 via the four-way valve 33, and the four-way valve 33 is in the second state. When switched to, the branch point 19a is connected to the outdoor heat exchanger 17 via the check valve 34.

The auxiliary heat exchanger 32 has a refrigerant outlet port of the outdoor heat exchanger 17 via an auxiliary pressure reducing device 35 (an example of a capillary tube is shown in the figure, but an expansion valve or the like) and a check valve 36. It communicates with the refrigerant inlet.

The first electromagnetic valve 37 is configured as an on-off valve, and the refrigerant discharged from the outdoor heat exchanger 17 functioning as a refrigerant evaporator during the heating operation is used as a pressure reducing device 1.
8 and the evaporator 15 are bypassed and the accumulator 19
It is configured to return to the side. In addition, the second solenoid valve 38
Is also configured as an opening / closing valve, so that the refrigerant discharged from the auxiliary heat exchanger 32 functioning as a refrigerant condenser during the dehumidifying operation is allowed to bypass the auxiliary pressure reducing device 35 and flow into the outdoor heat exchanger 17. Is configured.

In the refrigerating cycle thus constructed, the four-way valve 33, the first solenoid valve 37 and the second solenoid valve 38.
The flow of the refrigerant is controlled as described below by appropriately switching the above, and the heating operation, the cooling operation, and the dehumidifying operation are realized.

Specifically, during cooling operation, the four-way valve 33
Is switched to the first state and the first solenoid valve 37 is switched to the closed state (the second solenoid valve 38 may be de-energized), so that the refrigerant compressor is indicated by the arrow C in the figure. Refrigerant discharged from the 16 is a four-way valve 33 → check valve 34
→ Outdoor heat exchanger 17 → Decompression device 18 → Evaporator 14 → Accumulator 19 → Refrigerant compressor 16 flow in this order.

As a result, since the liquefied refrigerant is supplied to the evaporator 14, the air blown by the blower 13 is cooled by the evaporator 14. In this case, the branch point 19a upstream of the accumulator 19 is connected to the auxiliary heat exchanger 32 via the four-way valve 33, but in this state, the check valve 36 opens the refrigerant passage based on the pressure difference. Since it is closed, the inflow of refrigerant into the auxiliary heat exchanger 32 is substantially blocked.

During the heating operation, the four-way valve 33 is switched to the second state, the first solenoid valve 37 is switched to the open state, and the second solenoid valve 38 is switched to the closed state, as shown by an arrow H in the figure. , The four-way valve 33 → the auxiliary heat exchanger 32 → the auxiliary decompression device 35
The check valve 36, the outdoor heat exchanger 17, the first solenoid valve 37, the accumulator 19, and the refrigerant compressor 16 flow in this order.

As a result, the high temperature vaporized refrigerant is supplied to the auxiliary heat exchanger 32 and the liquefied refrigerant is supplied to the outdoor heat exchanger 17. That is, since the auxiliary heat exchanger 32 functions as a refrigerant condenser and heat is exchanged between the blown air by the blower 13 and the auxiliary heat exchanger 32, the blown air is heated. Become. Further, the outdoor heat exchanger 17 functions as an evaporator that exchanges heat with the air blown from the fan device 17a. In this case, the branch point 19a upstream of the accumulator 19 is communicated with the outdoor heat exchanger 17 via the four-way valve 33. In this state, the check valve 34 opens the refrigerant passage based on the pressure difference. Since it is closed, the refrigerant flow into the outdoor heat exchanger 17 is substantially blocked.

During the dehumidifying operation, the four-way valve 33 is switched to the second state, and the first solenoid valve 37 is closed and the second solenoid valve 38 is opened so that the arrow D
As shown by, the refrigerant discharged from the refrigerant compressor 16 is
Four-way valve 33-> auxiliary heat exchanger 32-> second solenoid valve 38-> check valve 36-> outdoor heat exchanger 17-> pressure reducing device 18-> evaporator 14
→ Flow in the order of accumulator 19 → refrigerant compressor 16.
In this case, the heat dissipation fan device 17a is stopped.

As a result, the high temperature vaporized refrigerant is supplied to the auxiliary heat exchanger 32, and the liquefied refrigerant that has passed through the pressure reducing device 18 is supplied to the evaporator 14. Therefore, in this case, the air blown by the blower 13 is once cooled in the evaporator 14 and then heated by the auxiliary heat exchanger 32. Therefore, in accordance with the decrease in the saturated steam temperature when the blower air by the blower 13 exchanges heat with the evaporator 14, the moisture in the blower air is condensed and removed on the surface of the evaporator 14. After that, as the blown air is reheated by heat exchange with the auxiliary heat exchanger 32, the relative humidity of the blown air is significantly reduced.

The four-way valve 33 and the first solenoid valve 37 as described above
The control of the second solenoid valve 38 is performed by the control device 25, as shown in FIG. 7. The control function of the control device 25 is basically the same as that of the first embodiment, but particularly during heating operation, the refrigerant in the auxiliary heat exchanger 32 is based on the pressure detected by the pressure sensor 30, for example. The condensing temperature is calculated, and the inverter device 2 is calculated based on the calculation result.
By adjusting the output frequency of 1, the condensing temperature, that is, the heating temperature is controlled.

Further, as shown in FIG. 6, the output of the inverter device 21 is constantly supplied to the AC motor 16a and is relayed by the control device 25 through relay switches 39R, 39S and 39T. 3 P
The TC heater 15 can also be supplied. In this case, the relay switches 39R, 39S, 39T are provided with mechanical make contacts, and in the ON state,
It is configured to switch to a state in which the three-phase AC output of the inverter device 21 is applied to the three PTC heaters 15 that are delta-connected with a phase difference of 2π / 3. That is, according to the control of the relay switches 39R, 39S, 39T, it is possible to switch between a state in which only the AC motor 16a is energized and a state in which both the AC motor 16a and the PTC heater 15 are energized.

Therefore, in the present embodiment having the above-described structure, during the heating operation, the AC motor 16a for the refrigerant compressor 16 is energized, and the four-way valve 33, the first solenoid valve 37 and the second solenoid valve 38 are set to predetermined levels. By switching to the state, the refrigeration cycle comes to function as a heat pump cycle, and when the heating capacity at this time is insufficient, the relay switches 39R, 39S, 39T are turned on, and the output of the inverter device 21 is changed to the AC voltage. In addition to the motor 16a, the PTC heater 15 is supplied with the heat, and the heat generated by the PTC heater 15 is accompanied by the elimination or supplement of the above-mentioned insufficient heating capacity.

In this case, in this embodiment, the PTC heater 1
Since the configuration is such that the AC output from the inverter device 21 is given to the inverter 5, the same effect as that of the first embodiment is obtained. In particular, in the present embodiment, as the relay switches 39R, 39S, 39T, those having a simple make contact for simply connecting and disconnecting the PTC heater 15 to and from the output side of the inverter device 21 may be used. Since the current flowing through the PTC heater 15 provided as a general heating source (that is, a current smaller than that when the PTC heater 15 is used as the main heating source as in the first embodiment) is intermittent, the structure thereof is Since the simplification and the contact capacity can be reduced, the cost of the relay switches 39R, 39S, 39T can be reduced, and the contact damage due to the arc can be reduced.

In the above embodiment, the three PTC heaters 15 are connected by delta connection and used. However, like the second embodiment, the three PTC heaters 15 are star connected (Y connection). Needless to say, it may be configured to be used.

10 to 13 show a fourth embodiment of the present invention, and only the parts different from the first embodiment will be described below. That is, this embodiment is characterized in that the inverter winder is driven by the heated windshield which is a kind of anti-fogging heater for heating the windshield of the electric vehicle.

Specifically, as shown in FIG. 12, for example, a windshield 40 for the front, which is shown in an enlarged state in a part of its cross-sectional structure, is made of laminated glass. It has a three-layer structure in which an intermediate layer 43 mainly made of resin is sandwiched between. In this case, the inner surface of the outer glass 41 (contact surface with the intermediate layer 43)
Is a transparent conductive film 4 mainly composed of a deposited film of Ag alloy.
4 is provided. By providing electrodes for power supply (only the first electrode 45a is shown in FIG. 12) at the upper and lower ends of the transparent conductive film 44, a heated window capable of heating the entire window glass 40 is provided. The shield 46 (corresponding to the electric heater in the present invention) is configured.

Specifically, as shown in FIG. 13, the first electrode 45a formed in a shape covering almost the entire upper end of the transparent electrode film 44 and the lower end of the transparent electrode film 44 are separated from each other in the left and right directions. Second electrodes 45b each formed by a predetermined width dimension
And a third electrode 45c are provided, so that between each of the electrodes 45a to 45c, R in FIG.
Virtual resistance indicated by a, Rb, and Rc (equivalent to an electric heater)
Will exist in a delta connection. As shown in FIG. 12, the black ceramic films 41a, 4a, 4c are formed on the opposing surfaces of the outer glass 41 and the inner glass 42 so as to conceal the first electrode 45a to the third electrode 45c from the front and back.
2a is provided.

Therefore, as shown in FIG.
In the Ted windshield 46, the first electrode 45a, the second electrode 45b, and the third electrode 45c are connected to the phase output terminals of the inverter device 21 via relay switches 47R, 47S, and 47T, respectively. The relay switches 47R, 47S and 47T are provided with mechanical make contacts.

Further, as shown in FIG. 11, an HWS switch 48 for turning on and off the heated windshield 46 is provided at a position where the driver can operate it, and the control device 25 has the HWS switch 48. Relay switches 47R, 47S, 47 according to the on / off operation of
It is configured to turn on / off T. Therefore, with respect to the heated windshield 46, the inverter device 2
The output of No. 1 can be selectively supplied via the relay switches 47R, 47S, 47T. The HWS switch 48 may also be used as a defrost switch.

According to the configuration of this embodiment described above, the AC motor 16a alone is energized and the AC motor 16a is controlled according to the control of the relay switches 47R, 47S, 47T.
It is also possible to switch to a state in which both the heat shield and the heat shield windshield 46 are energized, which makes it possible to remove frost, ice, and cloudiness due to moisture adhering to the windshield 40 as required. In this case, the heat shield windshield 46 itself consumes relatively large power (about 1000 to 1500 W / m ² ),
The relay switches 47R, 47S, 47 for disconnecting the power
T is the relay switch 26R, 26 in the first embodiment.
As with S and 26T, since an alternating current is interrupted, the contact damage due to the arc when the contact is opened is reduced as compared to when interrupting a DC current, even though the configuration is such that a large current is interrupted. become. As a result, even if a low-cost switch means having mechanical contacts such as the relay switches 47R, 47S, and 47T is used, there is no problem and the overall cost can be reduced.

When the load to be controlled is the heat-shielded windshield 46 as described above, it is general that the energization is performed independently of the air conditioning operation. It is also possible to obtain it from an inverter device for driving the motor.

FIG. 14 shows a fifth embodiment of the present invention in which the circuit configuration is modified in addition to the above fourth embodiment, and only different parts will be described below. That is, this fifth embodiment is similar to the relay switch 47 of the fourth embodiment.
Instead of R, 47S, 47T, relay switches 49R, 49S, 49T having mechanical transfer contacts are provided, and these relay switches 49R, 49S, 49T are
It is configured to switch between a state in which the three-phase AC output voltage from the inverter device 21 is applied to the AC motor 16a and a state in which the interphase voltage of the three-phase AC output is applied to the heated windshield 46. is there.

According to such a configuration, the AC motor 16
Since a and the windshield 46 are not energized at the same time, the heatshield 4
The applied voltage to 6, that is, the amount of heat generation can be changed arbitrarily.

A sixth embodiment of the present invention is shown in FIGS. That is, in FIG. 16, the heated windshield 50 (corresponding to the electric heater in the present invention) in this embodiment has a shape that covers almost the entire upper and lower ends of the transparent electrode film 44 provided on the wind glass 40. The pair of electrodes 50a and 50b thus formed is provided, and a space between the electrodes 50a and 50b is shown in FIG.
There will be a virtual resistance indicated by Rz.

As shown in FIG. 15, the heated windshield 50 has a pair of relay switches 51 provided with mechanical transfer contacts from the inverter device 21.
It is connected so as to be energized via R and 51S. still,
In this case, the output mode of the inverter device 21 is changed so as to function as a two-phase or single-phase inverter in the state in which the heated windshield 50 is energized.

FIG. 17 shows a seventh embodiment of the present invention, which will be described below. That is, FIG. 17 schematically shows the arrangement of all the windshields of an electric vehicle. The windshields 51, the rear windshields 52, and the windshields 53 provided on the driver's side doors are each shown in FIG. Ted Windshield 51A,
52A and 53A (corresponding to the electric heater in the present invention)
In addition to these, the Heated Windshield 5
For example, 1A, 52A and 53A are star-connected, and the three-phase AC output voltage from the inverter device 21 is supplied to the relay switches 47R, 47S, 47T as in the fourth embodiment or the relay switch 49R as in the fifth embodiment. , 49
The configuration is such that it is supplied via S and 49T.

Besides, the present invention is not limited to the above-described embodiments, but the following modifications or expansions are possible. In each of the above embodiments, the invention is applied to a manual type air conditioner, but it is also applicable to an automatic type air conditioner, and is not limited to an electric vehicle, and a refrigerant compressor in an air conditioning operation refrigeration cycle can be driven by a motor. The present invention can be applied to general automobiles that employ a driving structure. As the electric heater, not only the PTC heater but also other types of heaters can be widely used, and the number of installed heaters is not limited to three as in the above-described embodiment. If it is not necessary to consider the cost, a non-contact type switching element (triac, anti-parallel connected thyristor, etc.) may be used as the switch means. Although the heated windshield is targeted as the anti-fogging heater, other types of anti-fogging heaters such as a hot wire heater may be targeted.

[0067]

As is apparent from the above description, according to the first aspect of the invention, the electric power source of the electric heater provided as the heating source for the predetermined portion of the vehicle is set to the motor for the refrigerant compressor in the refrigeration cycle. Since the configuration is obtained from the inverter device provided as the power source of the switch unit through the switch unit, even when the switch unit including the mechanical contact is used as the switch unit, the reliability of the on / off control can be improved. As a result, the overall cost can be reduced.

According to the invention of claim 2, since the electric heater is a heater for heating operation for heating the atmosphere in the vehicle compartment, the PTC heater most commonly used as an electric heater for heating is used. Even in such a case, there is no fear that a migration phenomenon will occur, and it is possible to improve the operation reliability during long-term use.

According to a third aspect of the present invention, the electric heater is provided as a main heating source during the heating operation, and when the output of the inverter device is supplied to the electric heater, the switch means is used for the refrigerant compressor. 5. The motor is configured to be separated from the inverter device, so that the output change of the inverter device is directly linked to the output change of the electric heater, so that the heating capacity by the electric heater can be easily adjusted. In the invention, the refrigeration cycle is configured to be able to form a heat pump cycle for heating operation, and when the heating capacity of the refrigeration cycle is insufficient, the output of the inverter device is switched by the switch means to the motor for the refrigerant compressor and Since it is configured to supply both to the electric heater, the structure of the switch means is simplified and the contact capacity is reduced. Turned so that, it is possible reduce the cost of the switch means, it becomes possible to suppress the contact damage arc.

According to the fifth aspect of the invention, since the electric heater is an anti-fogging heater for heating a window glass for a vehicle, the window glass can be surely operated in an anti-fogging manner and disconnected. Even when the switch means having a mechanical contact for electricity is used, the reliability of the on / off control can be improved and the overall cost can be reduced.

According to a sixth aspect of the present invention, the inverter device is configured to generate a multi-phase AC output, and
Since a plurality of electric heaters to which the interphase voltage of the multi-phase AC output is applied and a plurality of switch means corresponding to each electric heater are provided, it is possible to reduce the current flowing to each electric heater. As a result, the switch means can have a small contact capacity and can be less likely to be damaged by the arc.

[Brief description of drawings]

FIG. 1 is an electrical configuration diagram of a main part showing a first embodiment of the present invention.

FIG. 2 is an overall electrical configuration diagram

FIG. 3 is a schematic cross-sectional view of a blower system.

FIG. 4 is a piping configuration diagram of the refrigeration cycle

FIG. 5 is a view corresponding to FIG. 1 showing a second embodiment of the present invention.

FIG. 6 is a view corresponding to FIG. 1 showing a third embodiment of the present invention.

FIG. 7 is a view corresponding to FIG.

FIG. 8 is a view corresponding to FIG.

FIG. 9 is a view corresponding to FIG.

FIG. 10 is a view corresponding to FIG. 1 showing a fourth embodiment of the present invention.

FIG. 11 is a view corresponding to FIG.

FIG. 12 is a schematic vertical sectional view showing a partially expanded state of a heated windshield.

FIG. 13 is a schematic diagram showing a heated windshield.

FIG. 14 is a view corresponding to FIG. 1 showing a fifth embodiment of the present invention.

FIG. 15 is a view corresponding to FIG. 1 showing a sixth embodiment of the present invention.

16 is a view corresponding to FIG. 13.

FIG. 17 is a view corresponding to FIG. 13 showing a seventh embodiment of the present invention.

[Explanation of symbols]

In the drawings, 1 is an air duct, 13 is a blower, 14 is an evaporator, 15 is a PTC heater (electric heater), 16 is a refrigerant compressor, 16a is an AC motor (refrigerant compressor motor),
Reference numeral 17 is an outdoor heat exchanger, 21 is an inverter device, 22 is an on-vehicle battery, 25 is a control device, 26R, 26S, 26.
T, 39R, 39S, 39T, 47R, 47S, 47
T, 51R and 51S are relay switches (switch means), 40, 51, 52 and 53 are window glasses, 4
Reference numerals 6, 50, 51A, 52A, and 53A denote heated windshields (electrical heaters).

Claims (6)

[Claims] 1. A refrigeration cycle for air conditioning operation,
In a vehicle air conditioner in which the power source of the refrigerant compressor motor in the refrigeration cycle is obtained from an inverter device that converts the output of a vehicle-mounted battery into AC power, an electric system provided as a heating source for a predetermined portion of the vehicle An air conditioner for a vehicle, comprising: a heater; and a switch means for selectively supplying an output of the inverter device to the electric heater. 2. The vehicle air conditioner according to claim 1, wherein the electric heater is a heater for heating operation for heating an atmosphere in a vehicle compartment. 3. The electric heater is provided as a main heating source during heating operation, and the switch means is arranged to supply the output of the inverter device to the electric heater. The vehicle air conditioner according to claim 2, wherein the motor for a vehicle is configured to be separated from the inverter device. 4. The refrigeration cycle is configured to be capable of forming a heat pump cycle for heating operation, and the switch means outputs the output of the inverter device to the refrigerant compressor when the heating capacity of the refrigeration cycle is insufficient. The vehicle air conditioner according to claim 2, wherein the air conditioner is configured to be supplied to both the motor and the electric heater. 5. The vehicle air conditioner according to claim 1, wherein the electric heater is an antifogging heater for heating a window glass for a vehicle. 6. The inverter device is configured to generate a polyphase AC output, and a plurality of electric heaters to which interphase voltage of the polyphase AC output by the inverter device is applied, and each of the electric heaters. The vehicle air conditioner according to any one of claims 1 to 5, further comprising a plurality of corresponding switch means.