JPH10297251A - Heater unit of air conditioner for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the air-flow resistance, and to provide the opening with the almost linear relationship with a temperature, by installing a heater core almost in parallel with the air flow line of an inflow passage, mounting a guide plate for flowing the air branched by a mix door almost straightly to the heater core, and mounting a center of the rotation of the mix door on the point edge of the guide plate. SOLUTION: An air inflow face of a heater core 23 is mounted almost in parallel with the air current flowed in the inflow passage 22. Further a pair of guide plates 30 are mounted at both edge parts of the heater core 23. These guide plates 30 guide the air passed therebetween, to be flowed almost straightly to the air inflow face of the heater core 23. The shafts of the mix doors 24 are mounted on the point edges of the guide plates 30. The height size B of the guide plate 30 is determined so that the air quantity flowed into the heater core 23 side and that flowed in the bypass passage 25 are equal to each other when the opening of the mix doors 24 is almost half. Whereby the opening of the mix doors 24 and the temperature of the conditioned air at each supply opening can be closed to the linear relationship.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heater unit for an air conditioner for a vehicle, in which air flows into a heater core at substantially right angles to the heater core and heat radiation efficiency is improved.

[0002]

2. Description of the Related Art As shown in FIGS. 4 and 5, a conventional heater unit of an air conditioner for a vehicle passes through a not-shown evaporator in a substantially rectangular parallelepiped unit case 1 and cooled air flows therethrough. An inflow passage 2 is formed, and a heater core 3 and a mixing door 4 are provided downstream of the inflow passage 2.
Is provided. By appropriately selecting the position of the mix door 4, that is, the degree of opening, the cool air from the inflow path 2 branches off and flows to the heater core 3 side and the bypass passage 5 side that bypasses the heater core 3, and is heated by the heater core 3. The mixed hot air and the cool air flowing down the bypass passage 5 are mixed in a mixing zone 6 to produce conditioned air at a predetermined temperature.

[0003] The evaporator is a heat exchanger that constitutes a part of a well-known cooling cycle, in which a low-temperature and low-pressure refrigerant flows. It is cooled by heat exchange. The heater core is a heat exchanger in which high-temperature engine cooling water flows, and the air flowing through the heater core exchanges heat with the high-temperature engine cooling water and is heated.

Therefore, when the opening degree of the mix door 4 is appropriately selected, the amount of air flowing to the heater core 3 and the amount of air flowing to the bypass passage 5 have a predetermined ratio. When cool air is obtained and these are mixed, conditioned air of a predetermined temperature can be obtained.

As shown in FIG. 5, the conditioned air enters a vehicle cabin through a defrost air outlet 7 and a vent air outlet 8 formed on the upper surface of the unit case 1 and a foot air outlet 9 formed on the bottom surface of the unit case 1. It is being blown out.

[0006] The above-described mixed door 4 includes a heater core 3
Can be set to a full cool position in which the bypass core 5 is fully opened and the bypass passage 5 is fully opened, a full hot position in which the heater core 3 is fully opened and the bypass passage 5 is fully closed, or an intermediate position between them. The operation is performed in accordance with the temperature set by a control lever (not shown) provided in the apparatus. In this case, the temperature set by the occupant by operating the control lever, that is, the opening of the mix door 4,
It is preferable that the temperature of the conditioned air blown out from each of the outlets 7, 8, 9 has a linear relationship as shown by a two-dot chain line in FIG.

For this reason, when the desired relationship cannot be obtained, the bypass passage 5 is provided with a temperature control rib 10 for restricting the flow of air in the bypass passage 5 to increase the ventilation resistance of the bypass passage 5, The air volume is adjusted so that the opening of the mix door 6 and the temperature of the conditioned air have a desired relationship, preferably a linear relationship (see Japanese Utility Model Laid-Open No. 5-32024).

However, when the temperature control rib 10 is provided in the bypass passage 5 as described above, on the other hand, the ventilation resistance when a large amount of cool air flows is increased. Therefore, a mac school door 11 is provided adjacent to the temperature control rib 10, and by opening this, the amount of cold air can be increased.
For example, in the bi-level mode of head cold foot temperature, if the tendency for the amount of cold air on the head side to decrease appears, the Mac school door 1
1, the ventilation resistance is reduced, and the amount of cold air flowing from the vent outlet 8 toward the upper body of the occupant is increased. Also, when the air volume becomes insufficient during the full cool, the Mac school door 11 is opened to increase the amount of cold air.
Further, in response to the linear movement of the temperature setting lever for setting the desired temperature by the occupant, the opening of the mix door 6 is controlled using a complicated link so that the outlet temperature changes linearly.

[0009]

However, in the heater unit shown in FIGS. 4 and 5, the opening degree of the mixing door 6 and the temperature of the conditioned air have a linear relationship, and the air flow resistance has to be reduced. In order to achieve the reduction, the temperature control rib 1
Although the 0 and Mac school doors 11 are provided, on the other hand, by providing them, the structure of the heater unit becomes complicated and the manufacturing cost increases.

As shown in FIG. 4 (plan view), since the heater core 3 is provided to be inclined with respect to the streamline of air, the air flowing into the heater core 3
Flows obliquely, and as a result, as shown in FIG.
As shown in FIG. 4, the smaller the angle at which air flows into the heater core 3, that is, the smaller the inclination angle, the greater the rate of decrease in the amount of heat radiation from the heater core. In the heater unit as shown in FIG. There is a possibility that the performance cannot be sufficiently exhibited.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and aims at reducing the ventilation resistance and changing the opening degree of the mixing door as linearly as possible with the temperature of the conditioned air at each outlet. It is an object of the present invention to provide a heater unit of an air conditioner for a vehicle, which is close to and can sufficiently exhibit heater performance.

[0012]

According to the first aspect of the present invention, there is provided an inflow passage through which air cooled by an evaporator flows in a unit case, and a downstream of the inflow passage. Is provided with a heater core and a mix door, and the degree of opening of the mix door causes cold air from the inflow passage to branch and flow to a heater core side and a bypass passage side that bypasses the heater core, and hot air heated by the heater core. In the heater unit of the air conditioner for an automobile, the cool air flowing down the bypass passage is mixed in the mixing zone to produce conditioned air of a predetermined temperature and blown out into the passenger compartment through each outlet. The heater core is disposed substantially parallel to the stream line of the flowing air flow, and is branched to the heater core side by opening and closing the mix door to flow. Air and provided a guide for guiding plate so as to flow substantially perpendicular to the heater core, and wherein the attaching the center of rotation of the mix door to the tip of the guide plate.

As described above, if the air that has passed through the mixed door flows into the heater core substantially orthogonally, the rate of reduction in the amount of heat radiation from the heater core can be reduced, and the heater performance can be sufficiently exhibited.

Further, since it is not necessary to provide a temperature control rib on the bypass passage side as in the related art, a sufficient air flow rate in the bypass passage can be ensured, and the ventilation resistance of the entire heater unit can be reduced.

Further, by adjusting the height of the guide plate, the ratio of the air flowing through the warm air passage on the heater core side to the bypass passage on the bypass side can be easily adjusted.

In the invention described in claim 2, the height of the guide plate is set so that the amount of cold air and the amount of hot air are equal when the opening of the mix door is substantially half. Features.

With this configuration, by adjusting the height of the guide plate, when the opening of the mix door is substantially half,
Since the amount of cold air and the amount of warm air can be set equal, the degree of opening of the mix door can be made closer to a linear relationship with the temperature control temperature of each outlet. Moreover, the control can be performed by a simple link mechanism that operates in response to the linear movement of the temperature setting lever for setting the desired temperature by the occupant.

Further, in the invention according to claim 3, when the mix door is fully closed on the heater core side, a closed space is formed by the mix door and the guide plate in front of the air inflow surface of the heater core. It is characterized by.

According to this configuration, the heat of the heater core is not easily transmitted to the bypass passage due to the formed closed space,
Temperature control efficiency can be improved.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a horizontal sectional view of a heater unit of an air conditioner for a vehicle according to an embodiment of the present invention,
FIG. 2 is a sectional view taken along line 2-2 of FIG.

As shown in FIGS. 1 and 2, an inflow passage 22 through which the cooled air flows is formed in the unit case 21 having a substantially rectangular parallelepiped shape.
Downstream of the inflow passage 22, a heater core 23 and a mix door 24 are provided. And mix door 24
Of the inflow passage 2 depending on the position of the
2 is supplied to the heater core 23 and the heater core 2
Branch to the side of the bypass passage 25 that bypasses 3
The warm air heated by the heater core 23 and the cool air flowing down the bypass passage 25 as they are are mixed in a mix zone 26 to produce conditioned air at a predetermined temperature.

The conditioned air is supplied to a defrost outlet 27 formed on the upper surface of the unit case 21 shown in FIG.
Alternatively, the air is blown into the vehicle cabin from the vent outlet 28 and the foot outlet 29 formed on the bottom surface of the unit case 21. The outlets 27, 28, 29 are provided with doors 27a, 28a, 29a which can be opened and closed, respectively.

In this embodiment, the air inflow surface of the heater core 23 is arranged substantially parallel to the airflow flowing through the inflow passage 22. Further, a pair of guide plates 3 are provided at both ends of the heater core 23, that is, at the start end and the end in the air flow direction.
0 is provided. The guide plates 30 guide the air passing therethrough so as to flow substantially orthogonally to the air inflow surface of the heater core 23. Therefore, it is preferable that the guide plate 30 is disposed substantially orthogonal to the airflow in the inflow passage 22. The guide plate 30
The shaft 31 of the mix door 24 is attached to the tip of the.

The height B of the guide plate 30 affects the ratio of the amount of air flowing to the heater core 23 and the amount of air flowing to the bypass passage 25. 24 is about half (1/2,
That is, when the heater core 2 rotates about 45 degrees),
It is preferable to set the amount of air flowing to the third side and the amount of air flowing to the bypass passage 25 to be equal (FIG. 3).
(B)).

That is, the height B of the guide plate 30 is
When the opening degree of the mix door 24 is substantially half, the ventilation resistance formed by the passage area on the heater core 23 side and the ventilation resistance formed by the passage area of the bypass passage 25 in consideration of the ventilation resistance of the heater core 23. Are set to be equal.

In this way, as shown in FIG. 3A, the opening degree of the mix door 24 and the temperature of the conditioned air at each outlet are linearly related to the theoretical line indicated by the two-dot chain line. It can be as close as possible.

Further, since the temperature control rib 10 (FIG. 4) conventionally required for the bypass passage 25 is eliminated and the air flow rate in the bypass passage 25 can be sufficiently secured, as shown in FIG. The ventilation resistance at the outlet 27 can be significantly reduced as compared with the conventional one (broken line), and the ventilation resistance of the entire heater unit can be reduced.

Further, since the air distributed to the heater core 23 side by the mix door 24 flows into the heater core 23 almost perpendicularly, as shown in FIG. , And the heater performance can be improved by 5 to 10% as compared with the related art.

Further, the mixing door 24 is connected to the heater core 2
When fully closed so that air does not flow into the third side, a closed space S where air does not move can be formed in front of the air inflow surface of the heater core 23 by the mix door 24 and the guide plate 30. In this case, since the air in the closed space S exhibits a heat insulating function, the heat of the heater core 23 is less likely to be transmitted to the bypass passage 25. As a result, the cool air flowing through the bypass passage 25 can flow down without being affected by the heat radiated from the heater core 23 to the surroundings, thereby improving the temperature control efficiency during cooling.

Further, since the temperature control rib 10 (FIG. 4) can be eliminated, a troublesome inspection of heat distribution and the like required for installing the temperature control rib 10 becomes unnecessary, and the unit design becomes easier as compared with the related art. Not only can it be improved.

Next, the operation of each air conditioning mode will be described. << Bi-level mode >> The bi-level mode is a head cold foot heat mode, in which the vent door 28a and the foot door 29a are opened, the cool air from the vent outlet 28 is blown toward the upper body of the occupant, and the warm air from the foot outlet 29 is used for the occupant. It blows out toward your feet.

In this mode, the mix door 24
Is set at a position between the fully closed state and the fully opened state, and cool air flowing down the inflow passage 22 from the evaporator 20 is supplied to the heater core 2.
The flow is performed at a predetermined ratio between the third side and the bypass passage 25 side.

In this case, the air flows through the guide plate 30 toward the mix door 24, but is guided by the guide plate 30 and flows substantially orthogonally to the air inflow surface of the heater core 23. Therefore, the rate of decrease in the amount of heat radiation of the heater core 23 can be reduced, and the heater performance can be sufficiently exhibited.

Further, for example, when the opening of the mix door 24 is halved, the ventilation resistance due to the passage area on the heater core 23 side is taken into consideration while considering the ventilation resistance of the heater core 23.
Since the ventilation resistance is equalized by the passage area of the bypass passage 25, an equal amount of air flow flows on the heater core 23 side and the bypass passage 25 side, respectively, and the mix zone 2
The cold air is blown out from the vent outlet 28 and the warm air is blown out from the foot outlet 29 without being mixed at 6, so that a temperature difference between the upper and lower sides without a sense of discomfort is obtained.

<< Vent Mode >> The vent mode is a cooling mode in which only the vent door 28a is opened, and cool air from the vent outlet 28 is blown toward the upper body of the occupant.

In this case, when the mix door 24 is in a full cool position, that is, in a fully closed state so that air does not flow into the heater core 23 side, the mix door 24 and the guide plate 30 cause the front surface of the air inflow surface of the heater core 23 to move. A closed space S in which air does not move is formed, and the effect of heat radiated from the heater core 23 to the periphery is prevented by the closed space S, and the cool air flowing through the bypass passage 25 is efficiently blown out from the vent outlet 28. .

When the mixing door 24 is set at the intermediate position, an equal amount of air flows on the side of the heater core 23 and the side of the bypass passage 25, and these are mixed in the mixing zone 26. ) And full cool (2
The air becomes air at an intermediate temperature (25 ° C.) of 0 ° C.) and is blown out from the vent outlet 28 to perform cooling.

<< Foot Mode >> The foot mode is a mode in which heating is performed. The vent door 28a is closed, the foot door 29a is opened, and hot air is blown out from the foot outlet 29 toward the feet of the occupant. Foot door 29
The defrost door 27a is also opened together with a, and warm air is blown not only from the foot outlet 29 but also from the defrost outlet 27 toward the windshield to clear the fogging of the window.

In this mode, the mix door 24
Is appropriately selected from a full hot position (a position where the bypass passage 25 is fully opened) to a position rotated by a predetermined angle.
In any case, the air flow is guided by the guide plate 30 and flows substantially perpendicularly to the air inflow surface of the heater core 23. Therefore, the rate of reduction of the heat radiation amount of the heater core 23 can be reduced, and the heater performance can be sufficiently improved. Can be demonstrated.

The hot air thus obtained is mixed with the cool air flowing through the bypass passage 25 in the mixing zone 26 and reaches a predetermined temperature, and is blown out from the foot outlet 29 or the defrost outlet 27.

<< Defrost Mode >> The defrost mode is a mode in which hot air is mainly blown toward the inner surface of the windshield or side glass to remove the fogging of the glass.
Only the differential door 27a is opened, the mix door 24 is half-opened, and warm air is blown to the defrost outlet 7.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified within the scope described in the claims.

[0043]

As described above, according to the first aspect of the present invention, since the air passing through the mix door flows into the heater core substantially orthogonally, the heater performance can be sufficiently exhibited. Further, since the conventional temperature control rib on the bypass passage side is eliminated, the ventilation resistance of the entire heater unit can be reduced. Further, by adjusting the height of the guide plate, the ratio of the air flowing to the heater core side and the air flowing to the bypass passage side can be easily adjusted.

According to the second aspect of the present invention, the height of the guide plate can be adjusted so that when the opening of the mix door is substantially half, the amount of cold air and the amount of hot air can be set equal. Therefore, the opening degree of the mix door and the temperature of the conditioned air from each outlet can be made closer to a linear relationship. Moreover, the control can be performed by a simple link mechanism that operates in response to the linear movement of the temperature setting lever for setting the desired temperature by the occupant.

Further, according to the third aspect of the present invention,
The closed space formed by the mixed door and the guide plate makes it difficult for the heat of the heater core to be transmitted to the bypass passage, thereby improving the temperature control efficiency.

[Brief description of the drawings]

FIG. 1 is a plan sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIGS. 3A to 3D are graphs showing characteristics of the heater unit according to the present embodiment.

FIG. 4 is a plan sectional view of a conventional heater unit.

FIG. 5 is a sectional view taken along line 5-5 in FIG. 4;

[Explanation of symbols]

 21 Unit case, 22 Inflow path, 23 Heater core, 24 Mix door, 25 Bypass path, 26 Mix zone, 27 Vent outlet, 28 Defrost outlet, 29 Foot outlet, 30 Guide Plate, 31 ... shaft (center of rotation).

Claims (3)

[Claims] An evaporator (2) is provided in a unit case (21).
0), an inflow passage (22) through which the air cooled flows is formed, a heater core (23) and a mixing door (24) are provided downstream of the inflow passage (22), and the mixing door (24) is opened. Depending on the degree, the cool air from the inflow path (22) branches off and flows to the heater core (23) side and the bypass passage (25) side that bypasses the heater core (23), and the hot air heated by the heater core (23) In the mixing zone (26), the cool air flowing down the bypass passage (25) is mixed in the mixing zone (26) to produce conditioned air at a predetermined temperature, and the conditioned air is blown into the vehicle cabin through the outlets (27, 28, 29). In the heater unit of the air conditioner for a vehicle, the heater core (23) is arranged substantially parallel to a streamline of an air flow flowing through the inflow path (22), and the heater core ( The air branched off to the 23) side is guided so as to flow into the heater core (23) substantially orthogonally. That the guide plate (30) is provided, the heater unit of the guide plate (30) air-conditioner for vehicle, wherein said rotational center (31) of the mixing door (24) that is attached to the tip of the. 2. The height (B) of the guide plate (30) is set such that the amount of cold air and the amount of hot air are equal when the opening of the mix door (24) is substantially half. The heater unit for an air conditioner for a vehicle according to claim 1, wherein: 3. The heater core according to claim 2, wherein
When the (23) side is fully closed, the mixing door (24) and the guide plate (30) form a closed space (S) in front of the air inflow surface of the heater core (23). The heater unit for an air conditioner for a vehicle according to claim 1 or 2, wherein