JP2765213B2 - Vehicle air conditioner - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a vehicle air conditioner capable of guiding cool air that cannot be heated from a passage bypassing a heater core to a vent outlet.

B. Prior Art Conventionally, a vehicle air conditioner as shown in FIG. 7 is known (for example, Nissan Motor Co., Ltd.
R10-1 issued in June 1990).

In FIG. 7, a blower fan 2, an evaporator 3, a heater core 4, and an air mix door 5 are provided in an air conditioning duct 1 as is well known, and a fresh vent passage (bypass passage) 6 that bypasses the heater core 4 is provided.
Is also provided. A vent outlet 7 having a center vent outlet 7C and left and right side vent outlets 7L and 7R is connected to the air-conditioning duct 1, and a foot outlet 11
Is provided. The vent outlet 7 blows air to the upper body of the occupant, and the underfoot outlet 11 blows air to the occupant's feet. The blowing from the vent outlet 7 is controlled by opening and closing control of the vent door 8, and the blowing from the foot outlet 11 is controlled by opening and closing control of the foot door 12.

The fresh vent passage 6 is provided so as to guide air downstream of the evaporator to a passage 9 between the vent outlet 7 and the vent door 8, and the fresh vent passage 6 has a fresh vent door (bypass door) for adjusting a flow rate thereof. ) 10 are provided. The openings of the air mix door 5, the vent door 8, and the fresh vent door 10 are respectively controlled by actuators (not shown).

In such an air conditioner, when the bi-level blowing mode is selected, the air that has passed through the air mixing door 5 (mixed air of the air A heated by the heater core 4 and the air B not heated) is blown out from the foot outlet. And the air that has passed through the air mixing door 5 and the fresh vent passage 6 (mixed air of the air A, B and the air C that has passed through the fresh vent passage 6) is blown out from the vent outlet 7, so that the effect of head cold foot heat is obtained. Is being planned.

C. Problems to be Solved by the Invention However, since the mixed air blown out from the vent outlet 7 includes the cooling air C in the bilevel mode as described above, the air mix door opening is set to be different from that in other modes. Similarly, if the control is performed, the vehicle may be overcooled, and the effect of head and foot fever may be remarkably manifested, which may cause discomfort to the occupant.

An object of the present invention is to provide an air conditioner for a vehicle in which an air temperature from a vent outlet in a bilevel mode is not overcooled.

D. Means for Solving the Problems To be described with reference to FIG. 1 which is a diagram corresponding to claims, the present invention is provided with a heater core 101 for heating cooling air, and a heater core 101 provided to be openable and closable with respect to the heater core 101. An air mix door 102 configured to increase the amount of air passing through the heater core as the size increases, and an air mix door 102
Air mix control means 103 for controlling the opening of the heater core 101, a bypass passage 104 for bypassing the heater core 101, and air passing through the bypass passage 104 such that the larger the opening, the larger the amount of air passing through the bypass passage 104. A bypass door 105 for adjusting the amount of air, a bypass door opening control means 108 for controlling the opening of the bypass door 105, and a mixture of air passing through the air mixing door 102 and cooling air passing through the bypass passage 104. A vent outlet 106 for blowing into the room,
A vent mode for blowing out the air passing through the air mix door 102 into the passenger compartment; a vent mode in which air is blown only from the vent port; and a vent mode for blowing air from both the vent port 106 and the foot port 107 The present invention is applied to a vehicle air conditioner in which a bi-level mode can be set. The above problem is solved by configuring the bypass door opening control means 108 and the air mix door opening control means 103 as follows.

The bypass door opening control means 108 controls the bypass door opening in the vent mode so as not to exceed the bypass door opening in the bi-level mode regardless of the opening of the air mix door. 103 is
In the bi-level mode, the opening of the air mix door is made larger under the same conditions as in the vent mode.

E. Operation The bypass door opening in the vent mode is controlled so as not to exceed the bypass door opening in the bi-level mode regardless of the opening of the air mix door. In the bi-level mode, the opening of the air mix door is larger under the same conditions than in the vent mode.

F. Embodiment -First Embodiment- A first embodiment of the present invention will be described with reference to FIGS. The configuration around the duct of the air conditioner is the same as that shown in FIG.

FIG. 2 shows an example of the control unit 40 of the vehicle air conditioner according to the present invention. A control circuit 41 (hereinafter, simply referred to as a CPU 41) including a CPU, a ROM, a RAM, etc., is connected via an input circuit 42 to an outside air temperature sensor 43 for detecting an outside air temperature Tamb, and an indoor temperature sensor 44 for detecting a vehicle interior temperature Tinc. , A solar radiation sensor 45 for detecting the amount of solar radiation Qsun, a suction temperature sensor 46 for detecting an air temperature (hereinafter referred to as a suction temperature) Tint downstream of the evaporator 4, and an air mixing door opening sensor for detecting the opening X of the air mixing door 11. 47 is connected, and various temperature information and heat amount information are input to the CPU 41 from these sensors 43 to 47.

Further, the CPU 41 has an intake actuator 50, an air mixed door actuator 51,
Vent door actuator 52V, foot door actuator 52F, defroster door actuator 52D, fresh vent door actuator 53 and blower fan control circuit
The blower fan control circuit 54 is connected to the blower fan motor 2M. The intake door actuator 50 controls the position of an intake door (not shown) that switches between suction of outside air and suction of vehicle interior air by the blower fan motor 2M.

The CPU 41 drives and controls various actuators such as the air mix door actuator 51 and the fresh vent door actuator 53 based on various information input from each of the sensors 43 to 47 to control the blowing temperature and the amount of air passing through the fresh vent passage 6. Control. In addition, the blower fan motor
Drive the 2M to control the air volume of the blower fan appropriately.

 Next, the operation of the embodiment will be described.

<Basic Flowchart> FIG. 3 is a flowchart showing the basic control of the air conditioning control device executed by the CPU 41.

In step S10, initial settings are made. In the normal auto air conditioner mode, for example, the set temperature Tptc is initially set to 25 ° C. In step S20, various information from each sensor is input.

The data information of each of these sensors will be specifically described. The set temperature Tptc is obtained from a control panel (not shown), the vehicle interior temperature Tinc is obtained from the indoor temperature sensor 44, and the outside air temperature is obtained.
Tamb is given from the outside temperature sensor 43, suction temperature Tint is given from the suction temperature sensor 46, and solar radiation amount Qsun is given from the solar radiation sensor 45. These vehicle interior temperature Tinc, outside air temperature Tamb, and solar radiation amount Qsun correspond to the vehicle heat load.

Next, in step S30, the outside air temperature Tamb obtained from the outside air temperature sensor 43 is processed to a value Tam corresponding to the actual outside air temperature, excluding the influence from other heat sources. Then step S
At 40, the solar radiation amount information as the amount of light from the solar radiation sensor 45 is processed into a value Q'sun as a heat amount suitable for subsequent conversion.
In step S50, the set temperature Tptc set on the control panel is processed to a value T'ptc corrected according to the outside air temperature. In step S60, as described later in detail, T′ptc, T
While calculating the target outlet temperature To from inc, Tam, Q'sun,
The opening of the air mix door 11 is controlled according to the deviation between the target outlet temperature To and the suction temperature Tint. Also this step
In S60, an opening correction according to the fresh vent door opening is also performed.

In step S70, on / off of a compressor (not shown) for pumping the refrigerant to the evaporator 3 is controlled. In step S80, each outlet is controlled. That is, in this type of air conditioner, a vent mode in which air is blown out from the vent outlet 7, a foot mode in which air is blown out from the foot outlet 11, and a differential mode in which air is blown out from a defroster air outlet (not shown) are set as the air outlet mode. As possible,
A bi-level mode (hereinafter, B / L mode) in which air is blown out from both the vent outlet 7 and the foot outlet 11 can be set. The setting of these outlet modes is based on the vent, foot, defroster door actuator 52V,
The operation is performed by driving the vent door 8, the foot door 12, and the defroster door (not shown) by 52F and 52D.

Next, in step S90, selection switching between the suction ports, that is, the outside air introduction port 7a and the inside air introduction port 7b is controlled. Step S100
Then, by controlling the blower fan 9, the air volume from the outlet is controlled. Thereafter, the process returns to step S20.

<Air Mix Door Control> FIG. 4 is a flowchart showing details of the air mix door control (step S60) of FIG. 3 described above.

In FIG. 4, first, constants A to G are initialized in step S601, and then the current air mix door opening X is input by the signal of the air mix opening sensor 47 in step S602. In step S603, it is determined whether or not the B / L mode is set. If not, in step S613, the fresh vent door 10 is fully closed by the fresh vent door actuator 53, and then step S6
Go to 08. In step S613, S = (A + D) T'ptc + B.Tam + C.Q'sun-D
・ Tinc + E− (FX + G) (82−Tint) −Tint Based on the target outlet temperature To and the actual outlet temperature (calculated from the air mix door opening X and the inlet temperature Tint).
Is determined. Where (A + D) T′ptc + B · Tam + C · Q′sun−D · Tin
c + E corresponds to the target outlet temperature To.

Then, in step S609, the deviation S is compared with a predetermined value So. If S <-So, in step S610, the air mixing door opening is set to the cold side, that is, the closing side so that the flow rate of air passing through the heater unit 10 is reduced. S
If> + So, in step S611, the air mixing door opening is set to the hot side, that is, the opening side so that the air flow rate passing through the heater unit 10 is increased. | S | ≦ + So,
In step S612, the current opening is maintained as it is.

On the other hand, if it is determined in step S603 that the B / L mode has been set, the process proceeds to step S604. Step S604
Then, the air mix door opening X obtained in step S602
Based on the characteristics shown in the figure, the opening of the fresh vent door
Xf is determined, and the fresh vent door 10 is controlled so as to have the opening Xf determined by the fresh vent door actuator 53. Here, the above characteristics are such that when the doors 5 and 10 are fully closed, the opening degrees X and Xf are zero, and when the doors 5 and 10 are fully open, 100
It is what it was. According to this characteristic, X and Xf are in a proportional relationship.

Next, in step S605, the value of the variable β is calculated from the illustrated characteristics based on the obtained fresh vent door opening Xf. In step S606, X ′ = X−β / 100 X ′ is obtained by the following. Next, in step S607, this X 'is set to X, and the flow advances to step S608.

According to the above procedure, the fresh vent door 10 is fully closed except during the bi-level mode (B / L mode),
The air blown out from the outlet is only the mixed air of A and B shown in FIG. At this time, the air mixing is performed based on the deviation S between the target outlet temperature To (calculated based on the vehicle thermal load) and the outlet temperature (calculated from the detected air mix door opening X and suction temperature Tint). The opening of the door is controlled.

On the other hand, in the B / L mode, as shown in the characteristic of step S604, based on the output of the air mixing door opening sensor 47, the opening of the fresh vent door 10 increases as the opening of the air mixing door 5 increases. . At this time, a value obtained by subtracting a value corresponding to the fresh vent door opening Xf from the detected air mix door opening X (detected X
Is smaller than X), and a deviation S is obtained using this X. The deviation S is larger than in the modes other than the B / L mode described above, and as a result, the controlled air mix door opening is more open than the above. As a result, the amount of air passing through the heater core 4 increases, and the temperature of the air blown out from the vent outlet 7 increases.

FIG. 5 shows the outlet temperatures from the vent outlet 7 and the foot outlet 11 in the B / L mode according to the air mix door opening X, and lv1 and lf1 indicate the vent outlet according to the present embodiment. Temperature characteristics and foot outlet temperature characteristics are shown, and lv2 and lf2 indicate conventional ones. According to this, it is understood that the temperature of the air blown out from the vent outlet 7 is higher than in the past.

In the configuration of the above embodiment, the CPU 41 and the air mix door actuator 51
103, the fresh vent passage 6 forms the bypass passage 104,
The fresh vent door 10 constitutes the bypass door 105, and the CPU 41 and the fresh vent door actuator 53 constitute the bypass door opening control means 108, respectively.

-Second Embodiment-In the first embodiment described above, when the B / L mode is set, the fresh vent door opening Xf according to the air mix door opening X as shown in the characteristic of step S4 in FIG. In this embodiment, an example is shown in which the fresh vent door 10 is fully opened regardless of the air mix door opening degree X.

FIG. 6 shows a flowchart of the air mix door control in this embodiment. Steps similar to those in FIG. 4 are denoted by the same step numbers.

In FIG. 6, when the B / L mode is determined in step S603, the process proceeds to step S621, and the fresh vent door 10 is fully opened. Next, in step S622, step
Using the air mix door opening X obtained in S602, X 'is calculated by X' = X-0.13, and in step S623, X = X 'is set, and the flow advances to step S608.

According to the above procedure, in the B / L mode, the fresh vent door 10 is fully opened, and at this time, a value obtained by subtracting 0.13 from the detected air mix door opening X (becoming smaller than the detected X) is used. X is newly set, and the deviation S is obtained using this X. Also in this case, the deviation S is calculated as B /
Since it becomes larger than in the modes other than the L mode, the controlled air mix door opening is on the opening side as described above. Therefore, as described above, the amount of air passing through the heater core 4 increases, and the temperature of the air blown out from the vent outlet 7 becomes higher by a predetermined value than in the B / L mode.

In the bilevel mode, air may be blown out from the defroster outlet.

G. Effects of the Invention According to the present invention, since the bypass door opening in the vent mode does not exceed the bypass door opening in the bi-level mode regardless of the opening of the air mix door,
In the vent mode, the amount of cool air passing through the bypass passage is suppressed, and sufficiently warm air can be blown out of the vent outlet when the vent mode is set during heating. In the bi-level mode, the opening of the air mix door is made larger under the same conditions as in the vent mode, so that the temperature of the air blown out of the vent outlet in the bi-level mode does not drop too much, and Head and foot heat effect is obtained.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims. 2 to 5 show a first embodiment of the present invention, FIG. 2 is a block diagram showing a control system of a vehicle air conditioner according to the present invention, FIG. 3 is a main flowchart, FIG. FIG. 5 is a flowchart showing the air mix door opening control, FIG. 5 is a diagram showing the blowing temperature in the bi-level mode, FIG. 6 is a flowchart of the air mix door opening control showing the second embodiment of the present invention, FIG. FIG. 7 is a diagram showing the overall configuration of the air conditioner. 4,101: Heater core 5,102: Air mix door 6: Fresh vent passage 7,106: Vent outlet, 8: Vent door 10: Fresh vent door 11,107: Underfoot outlet, 12: Foot door 41: CPU 47: Air mix door opening sensor 51: Air Mixed door actuator 52V: Vent door actuator 52F: Foot door actuator 53: Fresh vent door actuator 103: Air mix opening control means 104: Bypass passage, 105: Bypass door 108: Bypass door opening control means

Claims (1)

(57) [Claims] 1. A heater core for heating cooling air, an air mixing door provided to be openable and closable with respect to the heater core, wherein the air opening amount is larger as the opening degree is larger, the air mixing door is configured to: Air mix opening control means for controlling the opening of the mix door; a bypass passage for bypassing the heater core; and a larger amount of air flowing through the bypass passage so that the larger the opening, the larger the amount of air passing through the bypass passage. A bypass door to be adjusted; bypass door opening control means for controlling the opening of the bypass door; and a vent for blowing a mixture of air passing through the air mixing door and cooling air passing through the bypass passage into the vehicle interior. An outlet, and a foot outlet that blows air that has passed through the air mix door into the vehicle interior, from the vent outlet A vent mode for blowing only air and a bi-level mode for blowing air from both the vent outlet and the underfoot outlet, wherein the bypass door opening control means is configured to be in the vent mode. The bypass door opening is controlled so as not to exceed the bypass door opening in the bi-level mode regardless of the opening of the air mix door, and the air mix opening control means controls the air mix door in the bi-level mode. An air conditioner for a vehicle, wherein the opening degree of the air mix door is made larger under the same conditions as in the vent mode.