JP2564906B2 - Automotive air conditioners - Google Patents

Description

Description: [Industrial field of use] The present invention relates to a vehicle air conditioner for controlling the degree of cooling of a refrigerant evaporator.

[Prior Art] Conventionally, a refrigerant evaporator that cools passing air is provided in a ventilation duct for sending air toward a vehicle interior, and engine exhaust heat retained in engine cooling water is provided downstream of the refrigerant evaporator. BACKGROUND ART There is an air conditioner for a vehicle provided with a hot water heater that radiates heat.

In addition, an air mix damper that adjusts the amount of air that passes through the hot water heater and the amount of air that does not pass through is installed in the ventilation duct of this air conditioner.

Furthermore, the ventilation duct of the air conditioner is a window outlet that blows an airflow toward the window glass when the vehicle occupant selects the window blowing mode, and the upper half of the vehicle occupant when the vehicle occupant selects the upper body blowing mode. An upper body air outlet that blows an air flow toward the vehicle and a foot outlet that blows an air flow toward the foot of the vehicle occupant when the vehicle occupant selects the foot blowing mode.

Then, the air introduced into the ventilation duct is cooled when passing through the refrigerant evaporator, and at the same time, moisture in the air is removed (dehumidified). After that, a part or all of the air is heated to a predetermined temperature when passing through the hot water heater and blown out from the selected outlet.

Here, the dehumidification amount in the vehicle compartment and the cooling degree of the refrigerant evaporator have a correlation as shown in the graph shown in FIG. Conventionally, the degree of cooling of the refrigerant evaporator does not depend on the position of the outlet,
It has been controlled constantly.

[Problems to be Solved by the Invention] However, in the conventional air conditioner configured as described above, since the cooling degree of the refrigerant evaporator is kept constant irrespective of the required degree of dehumidifying amount, dehumidification is performed more than necessary, and it is not necessary for the user. There were issues such as giving a pleasant sensation and causing deterioration of fuel efficiency.

In general, the window blowing mode is used for dehumidification to secure visibility, the upper body blowing mode is used for blowing cold air during cooling operation, and the foot blowing mode is used for blowing hot air during heating operation. .

Therefore, in adjusting the dehumidification amount, it is desirable to control the dehumidification amount such that the former is higher in the order of the window blowing mode, the upper body blowing mode, and the foot blowing mode, that is, the cooling degree of the refrigerant evaporator is largely controlled.

An object of the present invention is to provide an automobile air conditioner capable of controlling the degree of cooling of a refrigerant evaporator according to the demand of each blowout mode.

[Means for Solving the Problems] The vehicle air conditioner of the present invention is a vehicle in which a window outlet that blows an air flow toward a window glass when selecting a window blowing mode or an upper body blowing mode is selected. It has an upper body outlet that blows airflow toward the upper body of the occupant and a foot outlet that blows airflow toward the feet of the vehicle occupant when the foot blowing mode is selected, and air is blown toward the passenger compartment. A refrigeration cycle comprising a ventilation duct for sending, a refrigerant evaporator disposed upstream of the window outlet of the ventilation duct, the upper body outlet and the foot outlet, and cooling the passing air, and the refrigerant. A configuration provided with a control means for controlling the degree of cooling of the evaporator so as to increase in the order of the window blowing mode, the upper body blowing mode, and the foot blowing mode in the order of the former is adopted.

[Operation] The automobile air conditioner of the present invention has the following operation due to the above configuration.

The air passing through the ventilation duct toward the passenger compartment is cooled by the refrigerant evaporator, and at the same time, the moisture in the air is removed (dehumidified).

At this time, the cooling degree of the refrigerant evaporator is the window blowing mode,
The upper body blowing mode and the foot blowing mode are controlled to increase in the order of the former. Therefore, when the window blowing mode is selected, the cooling degree of the refrigerant evaporator is controlled so that the cooling degree is very large and the dehumidifying amount is very high. Further, when the upper body blowing mode is selected, the cooling degree of the refrigerant evaporator is controlled so that the cooling degree is slightly large and the dehumidifying amount is slightly high.
Further, when the foot blowing mode is selected, air having a low degree of cooling and a low dehumidification amount can be obtained by controlling the degree of cooling of the refrigerant evaporator.

In this way, the air cooled and dehumidified by the refrigerant evaporator in response to the request of each blow mode is blown from the window outlet toward the window glass when the window blow mode is selected. Also, when the upper body blowing mode is selected,
The air is blown from the upper body outlet toward the upper body of the vehicle occupant, and is blown from the foot outlet toward the foot of the vehicle occupant when the foot blowing mode is selected.

[Advantages of the Invention] The automobile air conditioner of the present invention has the following advantages due to the above configuration and operation.

That is, since the cooling degree of the refrigerant evaporator is controlled according to the difference in the dehumidifying amount request in each blowout mode, the power consumption of the refrigeration cycle for supplying the refrigerant to the refrigerant evaporator is reduced in the blowout mode where the dehumidifying request is small. It becomes possible to reduce the power consumption to reduce the power consumption, and in the blowing mode where the dehumidification requirement is large, the dehumidification amount can be increased to effectively remove and prevent the fogging of the window glass.

[Embodiment] An automobile air conditioner of the present invention will be described based on an embodiment shown in the drawings.

FIG. 1 shows an air conditioner for an automobile which employs the present invention.

1 is an air conditioning system for automobiles (hereinafter abbreviated as air conditioning system)
Indicates.

The air conditioner 1 includes a ventilation duct 2 for sending air into a vehicle compartment (not shown), a blower 3 housed in the ventilation duct 2, a refrigeration cycle 4 in which a refrigerant circulates, and engine cooling water. Is provided with a hot water circuit 5 and a control device 6 which is a control means for controlling the cooling degree of the refrigerant evaporator.

The ventilation duct 2 has an inside air introduction port 22 or an outside air introduction port 23 that is switched by an inside / outside air switching damper 21 formed upstream, and a window outlet 24, an upper body outlet 25, and a foot outlet 26 formed downstream. Further, in the ventilation duct 2, the blower 3, the refrigerant evaporator 43 of the refrigeration cycle 4, the air mix damper 27, the hot water heater 51 of the hot water circuit 5, and the outlet mode switching dampers 28 and 29 are housed.

The blower 3 is provided with an inside air inlet 22 or an outside air inlet 23,
A fan 31 for introducing inside air or outside air to generate an air flow in the ventilation duct 2 toward the passenger compartment, and the fan 31
It has 31 driving motors 32.

The refrigeration cycle 4 includes a refrigerant compressor 41, a refrigerant condenser 42, a refrigerant evaporator 43, a liquid receiver 44, a temperature-operated expansion valve 45 that forms a refrigerant pressure reducing device, and a refrigerant pipe 46 that sequentially connects these in an annular shape. Composed.

The hot water circuit 5 is for supplying engine cooling water warmed in a cooling water jacket of the engine 10 through a cooling water pipe 52. The hot water circuit 5 includes a hot water heater 51 and a manual water valve 53.

This water valve 53 and air mix damper 27
The opening degree is changed according to the set position of the temperature adjusting lever 71 attached to the operation panel 7.

Here, the air mix damper 27 is interlocked with the manual water valve 53 of the hot water circuit 5, and the manual water valve 53 changes the amount of water flowing to the hot water heater 51 according to the opening degree of the air mix damper 27. Control. Therefore, at the time of maximum heating, the manual water valve 53 is fully opened and the air mix damper 27 is fully opened, and at the time of maximum cooling, the manual water valve 53 is fully closed and the air mix damper 27.
Is fully closed.

The control device 6 includes an air conditioner switch 61 that operates the refrigeration cycle 4, a blowout mode switching lever 62 that switches the blowout mode, a fan switch 63 that adjusts the rotation speed of the drive motor 32 of the fan 31 in three to four stages, and a cooling evaporator. A thermistor 64 for detecting the cooling temperature of 43 and a control circuit 65 are provided.

The blowout mode switching lever 62 connects a set resistance, and the set resistance is the resistance value which is set by the vehicle occupant in the window blowout mode, the upper body blowout mode, the bi-level (BI-LEVEL) blowout mode or the foot blowout mode. Control circuit 6
Send to

The fan switch 63 connects a set resistance, and the set resistance sends the rotation speed of the fan 31 set by the vehicle occupant or the air volume of the fan 31 to the control circuit 65 as a resistance value.

The thermistor 64 is provided downstream of the refrigerant evaporator 43 and a hot water heater.
It is mounted in the ventilation duct 2 between the upstream side of 51.
Alternatively, it is attached to the fins of the refrigerant evaporator 43.
The thermistor 64 is the temperature of the air passing through the refrigerant evaporator 43,
Alternatively, the temperature of the fin surface is detected as the degree of cooling of the refrigerant evaporator 43, converted into a resistance value signal, and sent to the control circuit 65.

The control circuit 65 inputs the above-mentioned signals to control the drive motor 32 of the electromagnetic clutch 11 and the fan 31.

This control circuit 65, when the window blowing mode, upper body blowing mode, bi-level blowing mode or foot blowing mode is selected by the blowing mode switching lever 62, the refrigerant circuit 43 of the refrigerant evaporator 43 corresponding to each blowing mode from the memory circuit 66. The target cooling temperature is read, the on / off of the electromagnetic clutch 11 is controlled according to the target cooling temperature and the cooling temperature detected by the thermistor 64, and the cooling temperature of the refrigerant evaporator 43 is controlled to the target cooling temperature.

As shown in the fourth graph, the target cooling temperature of the refrigerant evaporator 43 is such that the cooling temperature of the refrigerant evaporator 43 becomes higher in the order of window blowing mode, upper body blowing mode, bilevel blowing mode, and foot blowing mode in the latter order. Is set to. 67 indicates a battery for an automobile.

As shown in FIG. 2, the operation panel 7 includes an air conditioner switch 61, an outlet mode switching lever 62, a fan switch 63,
A temperature adjusting lever 71 and an inside / outside air switching lever 72 are attached.

The first is a method of controlling the cooling temperature of the refrigerant evaporator 43 of the present embodiment.
A description will be given with reference to FIGS.

FIG. 3 shows an operation flowchart of the method for controlling the cooling temperature of the refrigerant evaporator 43 of the control device 6 of this embodiment. The speed control of the fan 31 is omitted.

When the ignition switch (not shown) is turned on and the operation of the engine 10 is started, execution of the flowchart of FIG. 3 is started.

First, it is determined whether or not the fan switch 63 is turned on (step S1). When the fan switch 63 is not turned on (No), the drive motor 32 of the fan 31 is turned off or the drive motor 32 is maintained in the off state (step S
2).

Further, the electromagnetic clutch 11 that connects the engine 10 and the refrigerant compressor 41 is turned off, or the electromagnetic clutch 11 is maintained in the off state (step S3).
Repeat steps 1 to S3.

When the fan switch 63 is turned on in step S1 (Yes), the drive motor 32 of the fan 31 is turned on (step S4).

Next, it is determined whether or not the air conditioner switch 61 is turned on (step S5). When the air conditioner switch 61 is not turned on (No), the process proceeds to step S3.

When the air conditioner switch 61 is turned on (Yes) in step S5, the setting position of the blowing mode switching lever 62 is judged to judge whether or not the vehicle occupant selects the window blowing mode (step S6).

When the window blowing mode is selected (Yes), the memory circuit 66
The target cooling temperature Ta (hereinafter abbreviated as Ta) of the refrigerant evaporator 43 is read from the graph of FIG. 4 stored in (step 7). Then, the refrigerant evaporator detected by the thermistor 64
Read the cooling temperature te of 43 (hereinafter abbreviated as te) (step S
8).

 Next, it is determined whether or not te> Ta (step S9).

When te> Ta (Yes), in order to reduce te to Ta, the electromagnetic clutch 11 is turned on, the refrigerant compressor 41 is driven by the engine 10, and the refrigeration cycle 4 is operated (step S10).

When te> Ta is not satisfied (No), in order to raise te to Ta, the electromagnetic clutch 11 is turned off, the drive of the refrigerant compressor 41 is stopped, and the refrigeration cycle 4 is stopped (step S11).

When the window blowing mode is not selected in step S6 (No), the setting position of the blowing mode switching lever 62 is judged to judge whether or not the vehicle occupant selects the upper body blowing mode (step S12).

When the upper body blowout mode is selected (Yes), from the graph of FIG.
The target cooling temperature Tb of 43 (hereinafter abbreviated as Tb) is read (step S13). Then, the cooling temperature te of the refrigerant evaporator 43 detected by the thermistor 64 is read (step S14).

 Next, it is determined whether or not te> Tb (step S15).

When te> Tb (Yes), in order to reduce te to T, the electromagnetic clutch 11 is turned on and the refrigerant compressor 41 is driven by the engine 10 to operate the refrigeration cycle 4 (step S16).

When te> Tb is not satisfied (No), in order to raise te to Tb, the electromagnetic clutch 11 is turned off, the drive of the refrigerant compressor 41 is stopped, and the refrigeration cycle 4 is stopped (step S17).

When the upper body blowing mode is not selected in step S12 (No), the setting position of the blowing mode switching lever 62 is determined to determine whether or not the vehicle occupant is selecting the foot blowing mode (step S18).

When the foot blowing mode is not selected in step S18 (No), it is determined that the bi-level blowing mode is selected, and the target cooling of the refrigerant evaporator 43 is determined from the graph of FIG. 4 stored in the memory circuit 66. The temperature Tc (hereinafter abbreviated as Tc) is read (step S19). Then, the cooling temperature te of the refrigerant evaporator 43 detected by the thermistor 64 is read (step S2
0).

 Next, it is determined whether or not te> Tc (step S21).

When te> Tc (Yes), in order to reduce te to Tc, the electromagnetic clutch 11 is turned on and the refrigerant compressor 41 is driven by the engine 10 to operate the refrigeration cycle 4 (step S22).

When te> Tc is not satisfied (No), in order to raise te to Tc, the electromagnetic clutch 11 is turned off, the driving of the refrigerant compressor 41 is stopped, and the refrigeration cycle 4 is stopped (step S23).

Memory circuit 6 when the foot blowing mode is selected (Yes)
The target cooling temperature Td (hereinafter abbreviated as Td) of the refrigerant evaporator 43 is read from the graph of FIG. 4 stored in 6 (step S2
Four). Then, the refrigerant evaporator 4 detected by the thermistor 64
The cooling temperature te of 3 is read (step S25).

 Next, it is determined whether or not te> Td (step S26).

When te> Td (Yes), in order to reduce te to Td, the electromagnetic clutch 11 is turned on, and the refrigerant compressor 41 is driven by the engine 10 to operate the refrigeration cycle 4 (step S27).

When te> Td is not satisfied (No), in order to raise te to Td, the electromagnetic clutch 11 is turned off, the drive of the refrigerant compressor 41 is stopped, and the refrigeration cycle 4 is stopped (step S28).

After performing the control of steps S10, S11, S16, S17, S23, S24, S27, S28, step S1 and subsequent steps are repeated while the ignition switch is turned on.

That is, the cooling temperature of the refrigerant evaporator 43 is controlled to increase in the order of the window blowing mode, the upper body blowing mode, the bi-level blowing mode, and the foot blowing mode.

Therefore, when the vehicle occupant is selecting the window blowing mode with the blowing mode switching lever 62, the refrigerant evaporator 43
By controlling the cooling temperature of, the degree of cooling is very large, and air with a very high dehumidification amount can be obtained. In this way, the air cooled and dehumidified by the refrigerant evaporator 43 according to the request in the window blowing mode is blown from the window outlet 24 toward the window glass. Therefore, it is possible to prevent fogging of the window glass and always secure an optimum field of view.

Further, when the vehicle occupant selects the upper body blowing mode by the blowing mode switching lever 62, the cooling degree of the cooling temperature of the refrigerant evaporator 43 is controlled to obtain a slightly higher degree of cooling and a slightly higher dehumidifying amount of air. In this way, the air cooled and dehumidified by the refrigerant evaporator 43 according to the request for the upper body blowing mode is blown from the upper body outlet 25 toward the upper body of the vehicle occupant. Therefore, the upper body outlet 25
It is possible to blow cool cold air toward the upper body of the vehicle occupant.

Furthermore, the vehicle occupant uses the blowout mode switching lever 62 to
When the bi-level blowout mode is selected, the cooling degree is controlled to be a little small by controlling the cooling temperature of the refrigerant evaporator 43,
A slightly low amount of dehumidified air can be obtained. The air cooled and dehumidified by the refrigerant evaporator 43 in response to the request of the bi-level blow mode is adjusted by the air mix damper 27 or the like in the amount that passes through the hot water heater 51 thereafter, and the air volume of the vehicle occupant is discharged from the upper body outlet 25. The cool air is blown toward the upper half of the body and the warm air is blown from the foot outlet 26 toward the feet of the vehicle occupant.

Then, in response to the request for the foot blowing mode, the refrigerant evaporator 43
The air that has been cooled and dehumidified in the above manner has a low degree of cooling and a low dehumidification amount by controlling the cooling temperature of the refrigerant evaporator 43. In this way, the air cooled and dehumidified by the refrigerant evaporator 43 in accordance with the request for the foot blowing mode is blown from the foot outlet 26 toward the feet of the vehicle occupant. Therefore, hot air can be blown from the foot outlet 26 toward the feet of the vehicle occupant during the heating operation.

Therefore, without requiring an expensive humidity sensor or the like, by controlling the cooling degree of the refrigerant evaporator 43 in conjunction with the blowing mode, the refrigerant evaporator 43 can exhibit an appropriate dehumidifying action according to each blowing mode. Therefore, it is possible to prevent fogging of the window glass and quickly remove the window glass. In addition, when a large dehumidifying action is not exhibited, power saving operation can be performed.

[Other Embodiments] In this embodiment, the hot water type heater is arranged in the ventilation duct. However, the heater may be a ceramic heater or may not be arranged.

Although the refrigerant evaporator and the heater such as the hot water heater are arranged in series in the present embodiment, the refrigerant evaporator and the heater such as the hot water heater may be arranged in parallel. Further, a device such as a four-way valve that reverses the circulation direction of the refrigerant may be attached to the refrigeration cycle to form a refrigeration cycle of a heat pump type cooling and heating device.

In the present embodiment, the cooling degree of the refrigerant evaporator is controlled by the cooling temperature of the refrigerant evaporator, but the cooling degree of the refrigerant evaporator is controlled by the ratio of the ON time and the OFF time of the electromagnetic clutch (11). May be. In this case, the ON time of the electromagnetic clutch (11) is made longer in the order of the window blowing mode, the upper body blowing mode, and the foot blowing mode.

[Brief description of drawings]

FIG. 1 is a schematic view showing an automobile air conditioner / heater adopted in one embodiment of the present invention, and FIG. 2 is a front view showing an operation panel of the automobile air conditioner / heater adopted in one embodiment of the present invention. FIG. 3 is an operation flowchart of a control device for an air conditioning system for automobiles adopted in one embodiment of the present invention, and FIG. 4 is a refrigerant evaporator in each blowing mode of the air conditioning system for automobiles adopted in one embodiment of the present invention. 5 is a graph showing the target cooling temperature, and FIG. 5 is a graph showing the relationship between the dehumidifying amount and the cooling temperature of the refrigerant evaporator. In the figure, 1 ... Air conditioner for automobile, 2 ... Ventilation duct, 3 ...
Blower, 4 ... Refrigeration cycle, 5 ... Hot water circuit

Front page continuation (72) Inventor Naruzawa Naruzawa 1-1, Showa-cho, Kariya city, Aichi Nihon Denso Co., Ltd. (56) Reference JP-A-63-34218 (JP, A) SAIKAI Sho-59-109527 ( JP, U)

Claims (1)

(57) [Claims] (A) A window outlet that blows an airflow toward a window glass when the window blowing mode is selected, and an airflow is blown toward the upper body of a vehicle occupant when the upper body blowing mode is selected. An upper body air outlet and a foot outlet that blows an air flow toward the feet of the vehicle occupant when the foot outlet mode is selected, and a ventilation duct for sending air toward the passenger compartment, (b) A refrigerating cycle that is provided upstream of the window outlet, the upper body outlet, and the foot outlet of the ventilation duct, and includes a refrigerant evaporator that cools passing air; and (c) the degree of cooling of the refrigerant evaporator. The air conditioner for a vehicle, comprising: a control unit that controls the window blowing mode, the upper body blowing mode, and the foot blowing mode so as to increase in order of the former.