JP3335465B2 - 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 which can effectively remove fogging of a windshield.

[0002]

2. Description of the Related Art Conventionally, as an air conditioner for an electric vehicle capable of removing fogging of a windshield, for example, Japanese Unexamined Patent Publication No. 4-31 is disclosed.
There is a heating device for an electric vehicle described in Japanese Patent No. 7840.
That is, an in-vehicle battery, an interior air circulation type vehicle interior heating means, an electrothermal windshield formed by depositing a transparent thin-film resistor on a windshield that separates the interior of the vehicle from the outside, and a windshield temperature higher than the vehicle temperature. The heating device for an electric vehicle is provided with a heating device for heating the vehicle interior and a current supplying device for supplying electricity to the electrothermal windshield so that the height of the electric vehicle is increased.

[0003]

However, in the above-described heating apparatus for an electric vehicle, a transparent thin film resistor must be deposited on the windshield only to prevent fogging of the windshield. Cost and high production cost. Further, since the electric windshield is energized only to prevent fogging of the windshield, there is a problem that power consumption cannot be effectively used for air conditioning.

SUMMARY OF THE INVENTION In view of the above problems, the present invention has a simple structure for preventing fogging of a windshield, has a low production cost, and uses not only electric power to remove the fogging of the windshield, but also to reduce the fog. It is another object of the present invention to provide an electric vehicle air conditioner that can be effectively used for air conditioning.

[0005]

Means for Solving the Problems In order to achieve the above object, the present inventors have set the temperature of the inner surface of the windshield to be higher than the dew point or to remove the fog of the windshield. Focusing on the fact that the humidity of the air near the surface should be lowered to lower the dew point, the present invention was completed.

[0006] That is, an electric vehicle air conditioner according to the present invention includes an air conditioner unit,
Forming a heat pump cycle that circulates heat medium to perform cooling and heating, and an inside heat exchanger disposed in the air conditioning unit, an auxiliary heater disposed downstream of the inside heat exchanger, and a windshield DEF that blows air to the inside surface
DEF mode command means for instructing the air conditioning unit to perform a mode operation, and when a command signal of the DEF mode command means is input, when the operation mode of the heat pump cycle is the heating mode, the auxiliary heater is operated while performing the heating operation. When driving, when the operation mode of the heat pump cycle is off or in the cooling mode, while performing cooling operation in the heat pump cycle, by driving an auxiliary heater, air is blown out to the inner surface of the windshield to remove fogging. And a control device for controlling the air conditioning unit. Further, the operation mode may be selected based on an outside air temperature.

[0007]

Therefore, according to the present invention, at least one of the heat pump cycle and the auxiliary heater is driven to remove the fogging of the windshield.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will now be described with reference to FIGS. The heat pump cycle 1 is used in the electric vehicle air conditioner of the present embodiment. As shown in FIG. 1, the heat pump cycle 1 includes an outside heat exchanger 2 disposed in a front part of a vehicle body, an inside heat exchanger 3 disposed in an air conditioning unit 10 in a front part inside the vehicle, and a compressor 4. , A four-way valve 5, a capillary tube 6, and an accumulator 7.

When the interior of the vehicle is heated by the heat pump cycle 1, the heat exchange medium is circulated in the heating cycle. That is, the control device 30 described later switches the four-way valve 5 as shown by the solid line in FIG. 1 and drives the compressor 4 via the inverter 31 to make the heat exchange medium a high temperature and a high pressure. According to the indicated arrow, heat is radiated by the inside heat exchanger 3 through the four-way valve 5, then decompressed by the capillary tube 6, heat is absorbed from the outside air by the outside heat exchanger 2, and the accumulator 7 is again discharged from the four-way valve 5. And returned to the compressor 4 for circulation. As a result, the air sucked into the air conditioning unit 10 is heated by the in-vehicle heat exchanger 3 and is sent out as warm air into the vehicle.

When the interior of the vehicle is cooled by the heat pump cycle 1, the heat exchange medium is circulated in the cooling cycle. That is, the control device 30 switches the four-way valve 5 as shown by a dotted line in FIG. 1, drives the compressor 4 to set the heat exchange medium to high temperature and high pressure as described above, and follows the arrow shown by the dotted line in FIG. After the heat is radiated by the outside heat exchanger 2 through the four-way valve 5, the pressure is reduced by the capillary tube 6, the heat is absorbed from the air passing through the air conditioning unit 10 in the inside heat exchanger 3, and the accumulator 7 And circulates back to the compressor 4 via. Thereby, the air sucked into the air conditioning unit 10 is cooled by the heat exchanger 3 on the inside of the vehicle, and is sent out as cold air into the vehicle.

On the other hand, in the air conditioning unit 10 incorporating the heat exchanger 3 inside the heat pump cycle 1, an intake damper 11 for switching between inside and outside air is provided on the upstream side in the air conditioning unit 10, and the outside air 12a or the inside air 12b is air-conditioned. The suction is selectively performed in the unit 10. The suction of air into the air conditioning unit 10 is performed by rotating a blower 13 provided downstream of the intake damper 11 by a motor 14 connected to a control device 30.

On the downstream side of the blower 13, an in-vehicle heat exchanger 3 constituting the heat pump cycle 1 is arranged. The temperature near the heat exchanger 3 inside the vehicle is detected by a temperature sensor 15a provided near the downstream side, and a detection signal is input to the control device 30.

An air mix damper 17 for splitting and forming two flow paths 16a and 16b is provided downstream of the in-vehicle heat exchanger 3, and a PTC heater 20 as an auxiliary heater is provided in one flow path 16b. Is provided. This PTC
The heater 20 is a constant-temperature heating element whose resistance rapidly increases from a certain temperature and keeps the temperature constant by a current limiting action in a rapid change region of the resistance.

Further, at the outlet of the flow passage 16b, an adjusting damper 18 for adjusting the amount of air blown again by the PTC heater 20 is provided. When the air mix damper 17 rotates based on a control signal from the control device 30, the adjusting damper 18 rotates in accordance with the rotation based on the control signal.

A temperature sensor 15b is provided downstream of the flow paths 16a and 16b, and a DEF damper 1 rotated by an actuator (not shown) is provided downstream of the temperature sensor 15b.
9a, a VENT damper 19b, and a HEAT damper 19c are provided, and air is blown into the vehicle from respective outlets. In particular, the DEF
From the outlet to which the damper 19a is attached, air is blown to the inner surfaces of the front and rear windows (not shown).

The PTC heater 20 is connected to the relay 2
1 is connected to the control device 30 and the control device 3
On / off control is performed by 0.

The control unit 30 performs calculations based on various conditions input from an outside air sensor 32, an inside air sensor (not shown), and temperature sensors 15a and 15b, which are arranged in the vicinity of the heat exchanger 2 outside the vehicle. The air temperature and the air volume are controlled so that the occupant feels comfortable, and the dampers 19a, 19b, and 19c are turned according to the desired blowing mode selected by the DEF mode switch 33 or another mode switch. To open and close the desired air outlet.

Next, in order to remove the fogging of the windshield,
A control method when the DEF mode command switch 33 is turned on will be described based on a flowchart shown in FIG. First, in step S1, the occupant discovers fogging on the windshield and turns on the DEF command switch 33.
If the air conditioning unit 10 is set to the DEF operation mode in step 2, it is determined in step S3 whether the heat pump cycle 1 is a heating cycle. Then, when it is determined that the heat pump cycle 1 is a heating cycle, that is, HEAT
When warm air is being blown into the vehicle from the outlet opened by the rotation of the damper 19a, the PTC heater, which is an auxiliary heater, is turned on in step S4, and further warmed air is blown to the inner surface of the windshield. By raising the temperature of the inner surface above the dew point, fog on the windshield is removed. Then, in step S5, it is determined whether or not the DEF command switch is off. If it is determined that the DEF command switch is off, the occupant determines that the fogging of the windshield has been removed and the DEF command switch has been turned off. If it is determined that the switch is not turned off, the process returns to step S3.

On the other hand, when it is determined in step S3 that the heat pump cycle 1 is not a heating cycle, the heat pump cycle 1 is set to a cooling cycle in step S6.
Dehumidify and cool to reduce the humidity of the air. Further, step S
7, the PTC heater is turned on, the air whose temperature has been reduced by the dehumidifying cooling by the heat pump cycle is heated to a predetermined temperature, and then the heated dry air is blown onto the windshield, and the humidity of the air near the inner surface thereof is increased. Lowering the dew point to remove fogging on the windshield.
Then, in step S5, it is determined whether or not the DEF command switch is off. If it is determined that the DEF command switch is off, the occupant determines that the fogging of the windshield has been removed and the DEF command switch has been turned off. If it is determined that the switch is not turned off, the process returns to step S3.

According to this embodiment, since the PTC heater is turned on in the cooling / heating cycle, there is an advantage that the windshield can be removed from fogging without unnecessarily lowering the temperature in the vehicle interior.

In the above-described embodiment, the method of driving the heat pump cycle and the PTC heater to remove the fog when the heat pump cycle is the heating cycle has been described. However, the present invention is not limited to this. Depending on external conditions such as the temperature and the humidity in the vehicle, the heat pump cycle alone may be driven to remove the fogging.
Further, in the above-described embodiment, when the heat pump cycle is the cooling cycle, the heat pump cycle and P
Although the method of driving the TC heater to remove the fogging has been described, the present invention is not limited to this, and the outside air temperature, the inside air temperature,
Depending on external conditions such as the humidity inside the vehicle, the heat pump cycle alone may be driven to remove the fogging. Further, in the above-described embodiment, the case where the process is determined by first determining whether or not the heating cycle is performed has been described.
It goes without saying that the process may be performed by first determining whether or not it is the cooling cycle.

[0022]

As is apparent from the above description, according to the air conditioner for an electric vehicle according to the present invention, the fogging of the windshield can be removed at the same time as the air conditioning in the passenger compartment, so that the electric power can be used effectively. In particular, since the auxiliary heater is used while performing the cooling operation in the heat pump cycle, it is possible to remove the fogging of the windshield without unnecessarily lowering the temperature in the vehicle interior. Further, since the fogging of the windshield can be removed by the heat pump cycle and the auxiliary heater, there is no need to deposit a transparent thin film resistor on the windshield as in the conventional example. For this reason, there is an effect that the structure of the entire device is simplified, the production is not troublesome, and the production cost is reduced.

[Brief description of the drawings]

FIG. 1 is a schematic view of an electric vehicle air conditioner according to the present invention.

FIG. 2 is a flowchart showing a control method of the electric vehicle air conditioner shown in FIG.

[Explanation of symbols]

1: heat pump cycle, 3: heat exchanger inside the car, 10
... Air-conditioning unit, 20 ... PTC heater, 30 ... Control device, 32 ... Outside air sensor, 33 ... DEF command switch.

────────────────────────────────────────────────── ─── Continuation of the front page Examiner: Sano Shun (56) References JP-A-4-151318 (JP, A) JP-A 5-229334 (JP, A) JP-A 4-254212 (JP, A) JP-A-5-4511 (JP, A) JP-A-58-174017 (JP, A) JP-A-58-174018 (JP, A) JP-A-5-91925 (JP, U) JP-A-4-3812 (JP, A) JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60H 1/03 B60H 1/32 623 B60H 1/22 B60H 1/32 624 B60H 3/00 B60H 1/22 611 B60H 1 / 00 101 B60H 1/00 103 B60H 1/00

Claims (2)

(57) [Claims] 1. An air conditioning unit, a heat pump cycle for circulating a heating medium to perform cooling and heating, and an inside heat exchanger disposed in the air conditioning unit and a downstream side of the inside heat exchanger. An auxiliary heater disposed therein, DEF mode instruction means for instructing the air conditioning unit to perform a DEF mode operation for blowing air to the inner surface of the windshield, and
When the command signal of the F-mode command means is input, when the operation mode of the heat pump cycle is the heating mode, the auxiliary heater is driven while performing the heating operation, and when the operation mode of the heat pump cycle is off or in the cooling mode. And a control device for controlling the air conditioning unit so as to blow out air to the inner surface of the windshield and remove fogging by driving an auxiliary heater while performing cooling operation in the heat pump cycle. Air conditioner for electric vehicles. 2. The air conditioner for an electric vehicle according to claim 1, wherein the operation mode is selected based on an outside air temperature.