JP3302180B2 - Electric vehicle air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for an electric vehicle.

[0002]

2. Description of the Related Art In an air conditioner for an electric vehicle, when heating, a heat exchange medium of high temperature and high pressure by a compressor is circulated in the order of a heat exchanger inside the vehicle and a heat exchanger outside the vehicle to heat the inside of the vehicle. The air is blown into the vehicle while the air passing through the heat exchanger is radiated and warmed. If fogging occurs on the windshield, or if frost forms after parking for a long time in a cold place, the air blowing mode is switched to the DEF mode, and the heated air is blown on the windshield to prevent fogging and wear. I try to remove the frost.

[0003]

However, in the electric vehicle air conditioner, when the outside air temperature is low,
The heat exchange medium is also liquefied due to a decrease in temperature and is stored in the vehicle interior heat exchanger, the vehicle exterior heat exchanger, and these pipes. Therefore, even when the compressor is driven, the circulation of the heat exchange medium is immediate. Does not go smoothly. That is, by driving the compressor, first, the heat exchange medium on the vehicle side heat exchanger side is sucked into the compressor. However, as described above, since the heat exchange medium is liquefied, the suction amount is insufficient. Become. Therefore, as a result of a decrease in the flow rate of the heat exchange medium discharged to the in-vehicle heat exchanger, the flow rate in the in-vehicle heat exchanger also decreases. Can not warm up enough.

[0004] In this case, when the blower blow rate is increased from the beginning, the heat exchange medium passing through the heat exchanger inside the vehicle is more likely to be liquefied, so that the flow state of the heat exchange medium is improved. This causes a vicious cycle in which heat exchange in the heat exchanger inside the vehicle remains insufficient. In particular,
When fogging or frosting occurs on the windshield, the occupant increases the amount of air blow by increasing the rotation speed of the blower for the purpose of removing the windshield early, so that this problem becomes remarkable.

[0005] In view of the above problems, the present invention recovers the heat exchange performance of the heat exchanger inside the vehicle at the early stage of the heating operation and effectively removes fogging and frost on the windshield thereafter. It is an object of the present invention to provide an air conditioner for an electric vehicle that can be performed.

[0006]

In order to achieve the above object, according to the present invention, a heat exchange medium, which has been heated to a high temperature and a high pressure by a compressor, is circulated in the order of a heat exchanger inside the vehicle and a heat exchanger outside the vehicle. A heat pump cycle for operation, a compressor driving means for driving the compressor, a blower for blowing inside air or outside air to the inside of the vehicle through the inside heat exchanger, and a blower air volume setting means for setting the air volume of the blower An inside heat exchange temperature sensor disposed near the inside heat exchanger, a blow direction switching means for switching a blow direction into the vehicle by the blower, and a blow direction by the blow direction switching means. An air conditioner for an electric vehicle, comprising: a blowing direction setting unit configured to set a driving frequency of the compressor; If the DEF mode is set by direction setting means, the vehicle interior heat exchanger temperature detected temperature is a predetermined value of the sensor, i.e., 20 to 30 ° C., preferably 26
If the temperature is lower than 0 ° C., a signal for correcting the drive frequency of the compressor to be higher than the value set by the frequency setting means is output to the compressor driving means, and the amount of air blown by the blower is set by the blower air amount setting means. A signal for lowering the value below the value is output to the blower air volume control means. On the other hand, if the detected temperature is equal to or higher than a predetermined value, the signal for correcting the air flow by the blower above the set value of the blower air volume setting means. And an air conditioner control means for outputting the air pressure to the blower air volume control means.

[0007]

According to the structure of the present invention, when the DEF mode is set by the blowing direction setting means at the time of starting the heating operation, if the temperature detected by the heat exchange temperature sensor inside the vehicle is less than the predetermined value, The control means outputs a signal to the compressor control means and corrects the drive frequency of the compressor above the set value of the frequency setting means so that the pressure in the heat exchanger inside the vehicle increases, that is, The heat exchange medium is modified to flow in a vaporized state. At the same time, the air conditioner control means outputs a signal to the blower air flow rate control means and corrects the amount of air blown by the blower, thereby reducing the amount of air passing through the heat exchanger inside the vehicle and limiting the liquefaction of the heat exchange medium. I do. When the detected temperature is equal to or higher than a predetermined value, the amount of air blown by the blower is corrected by increasing the amount of air passing through the heat exchanger inside the vehicle, thereby increasing the amount of air blown to the windshield.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the air conditioner for an electric vehicle illustrated in FIG. 1, the cycle in which the heat exchange medium circulates is switched by the four-way valve 1 between a heating cycle and a cooling cycle. During these cycles, a compressor 2, an inboard heat exchanger 3, an outboard heat exchanger 4, and an accumulator 5 are provided outside the four-way valve 1.
Reference numeral 6 denotes a throttle valve that opens and closes the pipe a by driving the motor 6a.

The four-way valve 1 has a structure in which a rotary body having a pair of communication passages is accommodated in a valve body. The four-way valve 1 is switched as shown by a solid line at the time of heating and is switched at the time of cooling based on a control signal from a control device (not shown). It switches as shown by the dotted line.
The compressor 2 is driven by the power supplied from the compressor driving device 8 in accordance with the frequency set by the frequency setting device (temperature control lever) 7, and discharges the heat exchange medium sucked into the high temperature and high pressure state.

The inside heat exchanger 3 and the outside heat exchanger 4 have a structure in which flat tubes and corrugated fins are laminated and integrated. When the heat exchange medium flows meandering through the flat tubes,
It can exchange heat with the air passing through the fins.

The in-vehicle heat exchanger 3 is disposed in the unit 9 at the front of the vehicle, and radiates heat during heating to warm the passing air and cools it during cooling. On the other hand, the outside heat exchanger 4
Is mounted at the front of the vehicle and exchanges heat between a heat exchange medium flowing inside the vehicle and outside air passing outside. The accumulator 5 stores a heat exchange medium, separates gas and liquid, and supplies only gas to the compressor 2.

In the unit 9, in addition to the inside heat exchanger 3, a blower 10 located upstream of the inside heat exchanger 3 and a vehicle located near the outlet side of the inside heat exchanger 3. An internal heat exchange temperature sensor 11 is provided. The downstream portion of the unit 9 is a blow-out direction switching unit 12, in which a damper 13 is rotatably disposed so that the DEF blow-out port 12a can be opened and closed. It can be opened and closed.

The blower 10 includes a blower air volume setting device 1.
In accordance with the set value input in 4, the rotation is performed so that a desired air volume is obtained. Each of the dampers rotates in conjunction with each other, and opens and closes predetermined outlets (12a, 12b, etc.) according to an input signal from the blowout direction setting device 15. An input signal from the blower air volume setting device 14, an input signal from the blow direction setting device 15, and a temperature detected by the vehicle interior heat exchange temperature sensor 11 are input to an air conditioner control device 16, respectively.

The air conditioner control device 16 issues control signals to the compressor drive device 8 and the blower air volume control device 17 based on these input signals, whereby
Controls cooling / heating operation. Since the cooling operation is not directly related to the present invention, the heating operation will be described here with reference to the flowchart shown in FIG.

That is, first, in step S1, it is determined whether an ON signal has been input from a heating switch (not shown). When the ON signal is input, the heating operation is started in step S2. In this heating operation, an ON signal is output to the compressor driving device 8 so that the compressor 2
To circulate the heat exchange medium. In this heating operation, since the four-way valve 1 is switched as shown by the solid line, the heat exchange medium is supplied from the inside heat exchanger 3, the outside heat exchanger 4, the four-way valve 1 and the accumulator 5 to the compressor 2.
Circulate back to. Further, the blower amount set automatically or manually by the blower air amount setting device 14 is read, and the rotation of the blower 10 is started based on the set blower amount.

Subsequently, in step S3, it is determined whether or not the DEF mode has been selected. When the DEF mode has not been selected, it is determined that the normal heating operation state in which fogging or frosting has not occurred on the windshield, and the drive frequency of the compressor 2 is set to the set frequency in step S4. Then, in step S5, the vehicle interior heat exchange temperature sensor 11
Is a predetermined temperature (26 ° C. in this embodiment, but is preferably set within a range of 20 to 30 ° C.).
It is determined whether or not this is the case.

If the detected temperature t is less than 26 ° C., it is determined that the air passing through the heat exchanger 3 cannot be sufficiently heated, and the amount of air blown by the blower 10 is corrected downward in step S6. And wait until the temperature reaches 26 ° C. or higher. If the temperature is equal to or higher than 26 ° C., the flow rate of the blower 10 is returned to the flow rate set by the blower flow rate setting device 14 in step S7. Thereafter, the steps S3 to S7 are repeated until the heating switch is turned off in step S8 or the power supply is stopped by a key operation, that is, until a heating operation stop command is issued.

As described above, in the normal heating operation in which the mode other than the DEF mode is selected, if the temperature t detected by the in-vehicle internal heat exchange temperature sensor 11 does not exceed 26 ° C., the air flow rate by the blower 10 is corrected downward. As a result, the flow state of the heat exchange medium in the in-vehicle heat exchanger 3 can be recovered, and the heating operation can be reliably started. In addition, it is possible to prevent air that has not been sufficiently heated from being blown into the vehicle interior,
Discomfort experienced by the occupant can be minimized.

On the other hand, when the DEF mode is selected, the process proceeds to step S9, and the detected temperature t from the in-vehicle heat exchange temperature sensor 11 is a predetermined temperature (26 ° C. in this embodiment,
The temperature is preferably from 20 to 30C. ) It is determined whether or not it is above.

When the detected temperature t is less than 26 ° C., the flow of the heat exchange medium in the in-vehicle heat exchanger 3 does not proceed smoothly, and the heat exchange efficiency is reduced, as described in the background art. In step S11, the drive frequency of the compressor 2 is corrected upward, and then in step S11.
In step 2, the amount of air blown by the blower 10 is corrected downward, and the flow returns to step S9 to wait until the detected temperature t exceeds 26 ° C.

As described above, by increasing the driving frequency of the compressor 2, the flow of the heat exchange medium is promoted, the internal pressure of the heat exchanger 3 inside the vehicle is increased, and the amount of vaporization of the heat exchange medium is increased. Since the amount of air passing through the heat exchanger 3 inside the vehicle is reduced by reducing the amount of air blown by the blower 10 and the liquefaction of the heat exchange medium is suppressed, the heat exchanger inside the vehicle is improved. 3, the heat exchange performance can be recovered at an early stage.

When the detected temperature t is 26 ° C. or more, it is determined that no problem occurs even if the air flow by the blower 10 is increased, and the air flow by the blower 10 is corrected upward in step S10. I do. As a result, a large amount of air warmed by the vehicle interior heat exchanger 3 can be blown onto the windshield, and frost formation can be effectively removed.

Thereafter, similarly to the above, it is determined in step S8 whether the heating switch is turned off or the power is turned off by a key operation. If the power is turned off, the heating operation is terminated. If not, the process returns to step S3. .

As described above, when the DEF mode is selected, if the temperature detected by the inside heat exchange temperature sensor 11 does not exceed 26 ° C., the drive frequency of the compressor 2 is corrected upward and the blower 10 Is corrected downward, so that the heat exchange performance in the vehicle interior heat exchange 3 can be recovered at an early stage. Can maintain the flow of the heat exchange medium in a good state, and it is possible to blow a large amount of warmed air onto the windshield,
The generated fogging and frost can be effectively removed.

[0025]

As is clear from the above description, according to the present invention, when the DEF mode is selected at the time of starting the heating operation, if the temperature detected by the inside heat exchange temperature sensor is less than a predetermined value. Since the drive frequency of the compressor has been increased and the air flow rate of the blower has been corrected downward, the flow state of the heat exchange medium in the heat exchanger inside the vehicle is quickly restored to the state during normal heating operation. be able to. That is, when the flow state of the heat exchange medium is restored, the air flow rate by the blower is corrected upward. Therefore, even if the air flow rate is set to a relatively large value by an occupant or the like, the heat exchanger inside the vehicle may be used. As a result, the fogging and frost formation on the windshield can be removed early.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an air conditioner for an electric vehicle according to an embodiment.

FIG. 2 is a flowchart showing air conditioning control by the anti-fog control device of FIG.

[Explanation of symbols]

 2 Compressor 3 Inside heat exchanger 7 Frequency setting device 10 Blower 11 Inside heat exchange temperature sensor 14 Blow air volume setting device 15 Blowing direction setting device 16 Air conditioner control device 17 Blow air volume control device

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Toru Fujiwara 5658 Yoshikawa, Hachihonmatsucho, Higashihiroshima-shi, Hiroshima Japan Climate Systems Co., Ltd. (56) References JP-A-5-162535 (JP, A) JP JP-A-5-338433 (JP, A) JP-A-61-184117 (JP, A) JP-A-60-4409 (JP, A) JP-A-8-20215 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) B60H 1/22 B60H 1/00 B60H 1/32 F25B 1/00

Claims (1)

(57) [Claims] 1. A heat pump cycle for performing a heating operation by circulating a heat exchange medium heated to a high temperature and a high pressure by a compressor in the order of a heat exchanger inside a vehicle and a heat exchanger outside the vehicle, and compressor driving means for driving the compressor. A blower that blows inside air or outside air to the inside of the vehicle through the inside heat exchanger, a blower air volume setting unit that sets the amount of air to be blown by the blower, and a blower that is disposed near the inside heat exchanger. An air conditioner for an electric vehicle, comprising: a vehicle interior heat exchange temperature sensor; a blowing direction switching unit that switches a blowing direction into the vehicle by the blower; and a blowing direction setting unit that sets a blowing direction of the blowing direction switching unit. A frequency setting means for setting a driving frequency of the compressor; and a heating mode, wherein when the DEF mode is set by the blowing direction setting means, If the detected temperature is lower than a predetermined value in the car-side heat exchange temperature sensor, it outputs a signal for upward adjustment than the set value of the driving frequency of the compressor at the frequency setting means to said compressor drive means,
While outputting a signal for correcting the air flow rate by the blower to a value lower than a value set by the blower air volume setting means to the blower air volume control means, if the detected temperature is equal to or higher than a predetermined value,
An air conditioner for an electric vehicle, comprising: air conditioner control means for outputting to the blower air volume control means a signal for correcting the amount of air blown by the blower above a value set by the blower air volume setting means.