JPH04138908A - Air-conditioner for vehicle - Google Patents

Abstract

PURPOSE:To achieve appropriate effect to keep 'the head cool and the feet warm' by increasing the opening of an air-mix door in other mode than the bi-level mode under the same condition when the opening condition of a bypass door is detected in the bi-level mode, thereby preventing super cooling. CONSTITUTION:There is provided an air-mix door 102 so that the air-mix door may be capable of opening/closing a heater core 101 to heat cooled air and may increase the air volume passing through the heater core 101 the more when the opening becomes the larger. And the opening of the air-mix door 102 is controlled by means of an air-mix opening control means 103. On the other hand, the air volume passing through a bypass passage 104 of the heater core 101 is adjusted by means of a bypass door 105. In this case, the opening condition of the bypass door 102 is detected by a detecting means 108. In the air-mix opening control means 103, the opening of the air-mix door 102 is increased when the opened condition of the bypass door 105 is detected in the bi-level mode than in other mode than the bi-level mode under the same condition.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a vehicle air conditioner that can guide unwarmed cold air to a vent outlet from a passage that bypasses a heater core.

B. Conventional technology A vehicle air conditioner as shown in Fig. 7 has been known for some time (for example, Nissan Motor Co., Ltd. New Vehicle Manual R
IO-1 issued June 1990).

In FIG. 7, the air conditioning duct 1 includes a well-known rib blower fan 2. An evaporator 3, a heater core 4, and an air mix door 5 are provided, and a fresh vent passage (bypass passage) 6 that bypasses the heater core 4 is also provided. Further, the air conditioning duct 1 is connected with a vent blowout lower having a center vent blowout lower C and left and right side vent blowoff lowers L, 7R, and is provided with a foot blowout outlet 11. The vent blowout lower blows air to the occupant's upper body, and the foot blowout outlet 11 blows air to the occupant's feet. The air from the vent blow-out lower is controlled to open and close by the vent door 8, and the air blows from the foot air outlet 1.
1 is controlled by the opening/closing control of the foot door 12.

The fresh vent passage 6 is provided to guide the air downstream of the evaporator to the passage 9 between the vent blow-off lower and the vent door 8, and the fresh vent passage 6 is provided with a fresh vent door (bypass door) for adjusting the flow rate through which the fresh vent passage 6 passes. 10 are provided. Air mix door5. Vent door8. The opening degree of each fresh vent door 10 is controlled by an actuator (not shown).

In such an air conditioner, when the pie level blowout mode is selected, the air that has passed through the air mix door 5 (
Air A heated by heater core 4 and air B that is not heated
The mixed air) is blown out from the foot outlet, and the air that has passed through the air mix door 5 and the fresh vent passage 6 (the mixed air of the above air A, B and the air C passing through the fresh vent passage 6) is blown out from the vent outlet lower. By blowing out air, the effect is to cool the head and warm the feet.

C6 Problem to be Solved by the Invention However, since the mixed air blown out from the vent blowout lower includes the cooling air C in the bilevel mode, the opening degree of the air mix door cannot be adjusted in the same way as when setting other modes. If controlled, overcooling may occur, and the effect of cooling the head and heating the feet may become too pronounced and may even cause discomfort to the occupants.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle air conditioner that prevents the temperature of air from a vent outlet from becoming excessively cool during bilevel mode.

Means for Solving the Problems 00 To explain with reference to FIG. 1, which is a diagram corresponding to the claims, the present invention includes a heater core 101 that heats cooling air, and a heater core 101 that is provided so as to be openable and closable, and whose opening degree is large. an air mix door 102 configured to increase the amount of air passing through the heater core 101; an air mix opening control means 103 that controls the opening of the air mix door 102; a bypass passage 104 that bypasses the heater core 101; A bypass door 105 that adjusts the amount of air passing through the bypass passage 104, and a vent outlet 1 that blows out a mixture of air that has passed through the air mix door 102 and cooling air that has passed through the bypass passage 104 into the vehicle interior.
06 and a foot outlet 107 that blows out the air that has passed through the air mix door 102 into the vehicle interior, and can set a bilevel mode in which air is blown out from both the vent outlet 106 and the foot outlet 107 at least. Applicable to air conditioners.

The above problem is solved by providing a detection means 108 for detecting the open state of the bypass door 102 and configuring the air mix opening degree control means 103 as follows.

That is, when the open state of the bypass door 105 is checked in the bilevel mode, the air mix opening degree control means 103 changes the opening degree of the air mix door 102 under the same conditions more than when in the bilevel mode. Make it bigger.

81 action When the open state of the bypass door 105 is detected during the bilevel mode, the opening degree of the air mix door 102 becomes larger under the same conditions than when the air mix door 102 is not in the bilevel mode.

The amount of air passing through the heater core 101 increases as the air mix door opening degree increases. therefore,
By appropriately determining the increase in the amount of reheating by the heater core 101, overcooling of the mixed air blown out from the vent outlet 106 can be prevented.

F. Embodiment 1 First Embodiment A first embodiment of the present invention will be described with reference to FIGS. 2 to 5. Note that the configuration around the duct of the air conditioner is similar to that shown in FIG. 7.

FIG. 2 shows an example of the control section 40 of the vehicle air conditioner according to the present invention. A control circuit 41 (hereinafter simply referred to as CPU 41) consisting of a CPU, ROM, RAM, etc. has an input circuit 4.
an outside air temperature sensor 43.2 that detects the outside air temperature Tamb; An indoor temperature sensor 442 that detects the vehicle interior temperature T inc; a solar radiation sensor 45 that detects the amount of solar radiation Qsun; Air temperature downstream of evaporator 4 (hereinafter referred to as suction temperature)
Suction temperature sensor 46 for detecting Tint. An air mix door opening sensor 47 that detects the opening X of the air mix door 11 is connected, and various temperature information and heat amount information are input to the CPU 41 from these sensors 43 to 47.

Furthermore, the CPU 41 is connected to an intake actuator 50 . Air mix door actuator 51. Vent door actuator 52■, foot door actuator 52F.

A defroster door actuator 52D, a fresh vent door actuator 53, and a pro-a fan control circuit 54 are connected, and the pro-a fan control circuit 54 is connected to a pro-a fan motor 2M. Note that the intake door actuator 50 controls the position of an intake door (not shown) that switches between sucking in outside air or inhaling interior air by the proa fan motor 2M.

The CPU 41 controls the air mix door actuator 51 based on various information input from each sensor 43 to 47.
The blowout temperature and the amount of air passing through the fresh vent passage 6 are controlled by driving and controlling various actuators such as the fresh vent door actuator 53 and the fresh vent door actuator 53. Furthermore, the air volume control signal drives and controls the pro fan motor 2M via the pro fan control circuit 54 to appropriately control the air volume of the pro fan.

Next, the operation of the embodiment will be explained.

<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 performed, and in the normal automatic air conditioner mode, for example, the set temperature Tptc is set to 2.
Initial setting is 5℃. In step S20, various information from each sensor is input.

To specifically explain the data information of each of these sensors,
The set temperature T ptc is obtained from a control panel (not shown), the vehicle interior temperature T inc is obtained from the interior temperature sensor 44,
The outside air temperature Tamb is determined from the outside air temperature sensor 43 by the suction temperature T.
int is the amount of solar radiation Q sun from the suction temperature sensor 46
are respectively given from the solar radiation sensor 45. These vehicle interior temperatures Tinc.

The outside air temperature Taw+b and the amount of solar radiation Q sun correspond to the vehicle heat load.

Next, in step S30, the outside air temperature T amb obtained from the outside air temperature sensor 43 is processed to a value Tam corresponding to the actual outside air temperature by removing the influence from other heat sources. Next, in step S40, the solar radiation amount information as the light amount from the solar radiation sensor 45 is converted into a value Q as the heat amount suitable for subsequent conversion.
'Process to sun.

In step S50, a value T'ρ is obtained by correcting the set temperature Tptc set on the control panel according to the outside temperature.
Process to tc. In step S60, T'ptc, Tinc, Tam, as will be described in detail later.

The target blowout temperature To is calculated from Q'sun, and the opening degree of the air mix door 11 is controlled according to the deviation between the target blowout temperature TO and the suction temperature T int. Further, in this step S60, the opening degree is corrected according to the fresh vent door opening degree.

In step S70, a compressor (not shown) that pumps refrigerant to the evaporator 3 is controlled to be turned on or off. In step S80, each outlet is controlled. In other words, this type of air conditioner can be set to a vent mode in which air is blown out from the lower vent outlet, a foot mode in which air is blown out from the foot outlet 11, and a defroster mode in which air is blown out from a defroster outlet (not shown). Along with being said to be.

A bilevel mode (hereinafter referred to as B/L mode) in which air is blown out from both the lower vent outlet and the foot outlet 11 can also be set. These air outlet modes are set by the vent door 8. by the vent, foot, and defroster door actuators 52V, 52F, and 52D. This is done by driving the foot door 12 and defroster door (not shown).

Next, in step S90, the suction port, that is, the outside air introduction lower a
and controls selection switching of inside air introduction lower b. In step 5100, the flow rate from the air outlet is controlled by controlling the proa fan 9.

After that, the process returns to step S20.

<Air Mix Door Control> FIG. 4 is a flowchart showing details of the air mix door control (step 560) in FIG. 3 described above.

In FIG. 4, constants A-G are first initialized in step 5601, and then, in step 5602, the current air mix door opening degree X is input based on the signal from the air mix opening degree sensor 47. In step 5603, it is determined whether or not the B/L mode is set. If negative, in step 5613, the fresh vent door actuator 53 fully closes the fresh vent door 10, and then the process proceeds to step 8608. Step 561
In step 3, the deviation S between the target blowout temperature TO and the actual blowout temperature (calculated from the air mix door opening degree X and the suction temperature T int) is determined based on the following. Here, (A+D)T'ptc+B-Tam+C-Q'5un-
D-Tinc+E corresponds to the target blowout temperature TO.

Then, in step 5609, this deviation S is set to a predetermined value S.
Compare with o. If S<-8o, in step 5610, the air mix door opening degree is set to the cold side, that is, to the closed side so that the flow rate of air passing through the heater unit IO is reduced. In the case of S>+SO, in step 5611, the air mix door opening degree is set to the hot side, that is, to the open side so that the air flow rate passing through the heater unit 1o is increased.

If S1≦+SO, the current opening degree is maintained at step 5612.

On the other hand, if it is determined in step 8603 that the B/L mode is set, the process proceeds to step 5604. In addition to determining the opening degree Xf of the vent door, the opening degree X determined by the fresh vent door actuator 53
The fresh vent door 10 is controlled so that f.

Here, the above characteristics are such that the opening degrees X and Xf are 0 when each door 5 and 10 is fully open, and 100 when each door is fully open. According to this characteristic, X and Xf are in a proportional relationship.

Next, in step 5605, the value of the variable β is determined from the illustrated characteristics based on the fresh vent door opening degree Xf determined above, and in step 8606, using the above X and β, x' = x - β/100 Find X″. Next, in step 5607,
' is set to X and the process proceeds to step 8608.

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

On the other hand, in the B/L mode, as shown in the characteristics of step 5604, the opening degree of the fresh vent door 10 is increased as the opening degree of the air mix door 5 is larger, based on the output of the air mix door opening degree sensor 47. . Also, at this time, the value obtained by subtracting the value corresponding to the fresh vent door opening Xf from the detected air mix door opening Xf (which will be smaller than the detected X) is set as a new value X, and using this X, Find the deviation S. This deviation S is larger than when the mode is other than the above-mentioned B/L mode, and as a result, the controlled air mix door opening degree becomes more open than described above. This increases the amount of air passing through the heater core 4 and increases the temperature of the air blown out from the vent blowout lower.

FIG. 5 shows the temperature of the air outlet from the lower vent outlet and the foot outlet 11 in the B/L mode according to the air mix door opening degree X, where Qvl and Qfl are the vent outlet temperatures according to this embodiment. The characteristics and foot bath temperature characteristics are shown, and Qv2゜ρf2 shows the conventional one. According to this, it can be seen that the temperature of the air blown out from the vent blowing lower is higher than before.

In the configuration of the above embodiment, the CPU 41 and the air mix door actuator 51 control the air mix opening control means 103, the fresh vent passage 6 controls the bypass passage 104, and the fresh vent door 1o controls the bypass door 1.
05 and the CPU 41 constitute the detection means 108, respectively.

-Second Embodiment- In the first embodiment described above, when the B/L mote setting is specified, the fresh vent door opening is determined according to the air mix door opening X as shown in the characteristics of step S4 in FIG. Although the case where Xf is determined has been shown, this embodiment shows an example 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 air mix door control in this embodiment. Note that steps similar to those in FIG. 4 are given the same step numbers.

In FIG. 6, if it is determined in step 5603 that the mode is B/L mode, the process proceeds to step 5621, and the fresh vent door 10 is fully opened. Then step 5622
Then, using the air mix door opening degree X obtained in step 5602, X' is calculated as follows:

According to the above procedure, the fresh vent door 10 is fully opened in the B/L mode, and at this time, the value obtained by subtracting 0.13 from the checked air mix door opening degree
(which is smaller than the detected X) is set as a new X, and the deviation S is determined using this X. In this case as well, the deviation S is larger than in the case other than the above-mentioned B/L mode, so the controlled air mix door opening degree is on the more open side than 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 blowout lower becomes B.
/L mode is higher than that in other modes by a predetermined value.

Note that air may also be blown out from the defroster outlet during the bi-level mode.

G0 Effects of the Invention According to the present invention, when the open state of the bypass door is detected in the bilevel mode, the opening degree of the air mix door is made larger under the same conditions than when the bypass door is in the bilevel mode. As a result, the air blown out from the vent outlet during the bi-level mode is at a higher temperature than before, preventing proper cooling, and providing an appropriate effect of cooling the head and heating the feet, thereby eliminating discomfort to the occupants.

[Brief explanation of drawings]

FIG. 1 is a complaint correspondence diagram. 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, and FIG. 4 5 is a flowchart showing the air mix door opening degree control, FIG. 5 is a diagram showing the blowout temperature in the bilevel mode, FIG. 6 is a flowchart showing the air mix door opening degree control showing the second embodiment of the present invention, and 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: Foot outlet 12: Foot door 4
1: CPU 47: Air mix door opening sensor 109° 51: Air mix 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:
Detection means 201: Bypass opening control means Patent applicant: Nissan Motor Co., Ltd. Patent attorney Noriyuki Nagai Figure 1 Figure 3 Figure 4

Claims (1)

[Scope of Claims] A heater core that heats cooling air; an air mix door that is provided to be openable and closable with respect to the heater core and configured such that the larger the degree of opening of the air mix door, the greater the amount of air that passes through the heater core; an air mix opening control means for controlling the opening of the air mix door; a bypass passage for bypassing the heater core; a bypass door for adjusting the amount of air passing through the bypass passage; and an air mix opening control means for controlling the opening of the air mix door; A vent outlet that blows out mixed air of the cooling air that has passed through the bypass passage into the vehicle interior, and a foot outlet that blows out the air that has passed through the air mix door into the vehicle interior, at least the vent outlet and the foot outlet. A vehicle air conditioner capable of setting a bilevel mode in which air is blown out from the air outlet at the same time, further comprising a detection means for detecting an open state of the bypass door, and the air mix opening degree control means is configured to control the opening state of the bypass door in the bilevel mode. A vehicle air conditioner characterized in that, when an open state of a bypass door is detected, the opening degree of the air mix door is made larger under the same conditions than when the air mix door is not in a bilevel mode.