JP2002316533A - Air conditioner for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner for a vehicle capable of changing the expansion of the air supply while suppressing the increase in the parts number and the cost at low values. SOLUTION: A projecting part 39 of a substantially semi-circular section is provided on an opening part 37a of a side bent duct 37 in a projecting manner inside the duct. When the conditioned air speed is low, the conditioned air flows along the surface of the projecting part 39 to form diffused air over the entire opening part 37a. On the other hand, if the conditioned air speed is high, the conditioned air flows separate from the surface of the projecting part 39 to form the air concentrated in the vicinity of the center of the opening part 37a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner.

[0002]

2. Description of the Related Art In a conventional automobile air conditioner, for example,
As in the device disclosed in JP-A-5-155246, a partition plate such as a louver is provided at an air-conditioned air outlet,
The direction and volume of air are changed by changing the direction of the partition.
The direction of the louver can be changed automatically by an actuator via a link or the like, or can be changed manually.

[0003]

However, in the above-described conventional apparatus, when the spread angle of the blown air is adjusted according to the airflow, the airflow is changed by changing the rotation speed of the blower fan and the like. The louver needed to be turned. In addition, a drive mechanism and an actuator for moving the louver and a controller for controlling them are required, which causes an increase in the number of parts and an increase in cost. On the other hand, manually changing the angle of the louver to change the spread of the blowing air was a very complicated operation and was cumbersome.

An object of the present invention is to provide an air conditioner for a vehicle which can change the spread angle of the blow-out air while suppressing an increase in the number of parts and an increase in cost.

[0005]

An embodiment of the present invention will be described with reference to FIGS. 1, 3 and 10. FIG. (1) When described in association with FIG. 1 and FIG. 3, the invention of claim 1 is a blower means 13, 14, 19, 2 that can blow at least two types of conditioned air at a low speed and a high speed.
2, 25-31 and blowing means 13, 14, 19, 22,
The present invention is applied to a vehicle air conditioner having a blower duct 37 that blows out the conditioned air blown by 25 to 31 into the vehicle interior, and protrudes inside the duct of the blower duct 37 and has a substantially semicircular cross section in the blower direction. The above-mentioned object is achieved by forming at least a part of the duct inner peripheral surface of the blowout opening 37a of the blower duct 37. (2) The invention of claim 2 is the vehicle air conditioner according to claim 1, wherein when the wind speed is low, the Reynolds number of the conditioned air is about 10 ³ or more and about 10 ⁵ or less, and the wind speed is high. In this case, the curvature radius L and the wind speed of the convex portion 39 are set so that the Reynolds number is about 10 ³ or less. (3) Explaining with reference to FIG. 10, the invention of claim 3 is the vehicle air conditioner according to claim 1 or 2, wherein the cross-sectional area of the blow-out opening 45 a is changed from the protrusion 39 to the opening 45 b. It gets larger as it approaches.

In the section of the means for solving the above problems, the drawings of the embodiments of the present invention are used to make the present invention easier to understand, but the present invention is not limited to the embodiments of the present invention. Not something.

[0007]

(1) According to the first aspect of the present invention, by providing the convex portion at the outlet opening of the duct, when the conditioned air is at a low speed, the diffused air spreading over the entire opening is blown out, and the air conditioning is performed. When the wind is high speed, concentrated wind blows out at the center of the opening. As a result, when the air volume is large at the beginning of the cool-down period, intensive air conditioning air is automatically blown out to provide a comfortable cooling feeling. Since it is applied to a wide range, the feeling during air conditioning can be improved. (2) By setting the radius of curvature and the wind speed of the convex portion as in the second aspect of the invention, a diffused wind and a concentrated wind can be reliably obtained according to the low speed and high speed of the conditioned air. (3) According to the third aspect of the invention, the difference between the diffused wind and the concentrated wind becomes larger, and a sharp air-conditioned wind is obtained.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment of a vehicle air conditioner according to the present invention, and is an overall configuration diagram of the air conditioner. Reference numerals 11 and 12 designate an outside air intake port and an inside air intake port provided on the upstream side of the vehicle air conditioner 1, and the ratio of the outside air to the inside air to be taken is determined by the intake door 13
Will be adjusted by The air sucked in from both inlets 11 and 12 is blown to the downstream side (left side in the figure) of the air conditioner 1 by the blower fan 14, heat exchange is performed by the evaporator 15, and becomes cool air. The blower fan 14 is driven to rotate by a fan motor 26.

On the downstream side of the evaporator 15, the flow path of the cool air is divided into a flow path 17 passing through the heater core 16 and a flow path 18 bypassing the heater core, and merges again downstream of the heater core 16. The cool air passing through the flow path 17 is supplied to the heater core 1.
6, heat exchange is performed to generate warm air, and the warm air and the cool air that has passed through the flow path 18 merge to form conditioned air having a predetermined temperature. An air mix door 19 is provided at a branch point between the flow path 17 and the flow path 18. By changing the position of the air mix door 19, the proportion of air passing through the flow paths 17 and 18 is adjusted.

Reference numeral 20 denotes a differential duct, and reference numeral 21 denotes a vent / foot duct. By changing the opening / closing position of the differential door 22, the differential duct 20 and the vent / foot duct 2 are opened.
The air flow of the air-conditioning air to be distributed to 1 is adjusted. Differential duct 2
0 guides the conditioned air to a defrost air outlet (not shown) arranged near the window shield glass of the instrument panel. The vent / foot duct 21 is branched at its downstream into a vent duct 23 and a foot duct 24, and 25 is a V / F for adjusting the flow rate of the conditioned air distributed to the vent duct 23 and the foot duct 24.
The door.

The intake door 13, the air mix door 19, the differential door 22, and the V / F door 25 are opened and closed by door actuators 27, 28, 29, and 30, respectively. The fan motor 26 and the door actuators 27 to 30 are controlled by the controller 31. By changing the rotation speed of the blower fan 14, the wind speed of the air flowing through each duct can be changed. The wind speed can also be changed by changing the opening of each of the doors 13, 18, 22, and 25 to change the air volume in each duct.

FIG. 2 is a perspective view showing the driver's seat 35 and a part of the instrument panel 36. The vent duct 23 of FIG. 1 branches into two systems of ducts downstream of the vent duct 23. One of the ducts guides the conditioned air to a center vent outlet 32 arranged near the center of the instrument panel 36, and the other one. Guides the conditioned air to the side vent outlets 33 provided on both the left and right sides. The foot duct 24 in FIG. 1 guides the conditioned air to a foot outlet (not shown) provided near the feet of the driver's seat and the passenger's seat. The center vent outlet 32 and the side vent outlet 33 are provided with louvers 34, respectively.

FIG. 3 is a view showing a side vent duct 37 for guiding conditioned air to the side vent outlet 33 of FIG.
(A) is a perspective view of the side vent duct 37, (b) is a transverse cross-sectional view, and (c) is an enlarged view of a portion indicated by reference numeral A in (b). The cross-sectional view of FIG. 3B is a cross-section along the two-dot chain line 38 of FIG. 3A, and the conditioned air flows from the left side to the right side in the drawing. In the opening 37 a of the side vent duct 37, a convex portion 39 protruding inside the duct 37 is formed so as to go around the side vent duct 37. FIG.
As shown in the enlarged view of (c), the cross-sectional shape of the projection 39 is a semicircle, and the radius of curvature of the projection 39 is L.

Next, the relationship between the convex portion 39 and the form of blowing the conditioned air will be described. The condition of the conditioned air flowing near the convex portion 39 of the side vent duct 37 is shown in FIG.
(C) As shown in FIG.
Is almost the same as the flow around the columnar object 40 when. The state of the flow around the cylindrical object 40 changes depending on the Reynolds number Re. The kinematic viscosity coefficient of the fluid is ν, the flow velocity of the fluid is u, and the representative length is the radius L of the cylindrical body 40.
Then, the Reynolds number Re is expressed by the following equation (1).

## EQU1 ## Re = u · L / ν (1)

Generally, when the flow velocity is small and the Reynolds number R
When e is small, as shown in FIG.
Tends to flow along the cylindrical object 40 due to viscosity.
When the flow velocity increases and the Reynolds number Re increases,
As shown in FIG. 4B, the fluid 41 is easily separated from the cylindrical object 40. When the Reynolds number Re further increases, as shown in FIG. 4 (c), it becomes easier to flow along the cylindrical object 40 again, but it becomes a turbulent flow region.

FIG. 5 shows the Reynolds number Re and the cylindrical object 40.
Is a graph showing the relationship between the resistance coefficient C _D of. From the relationship of FIG. 5, when the Reynolds number Re is approximately Re <10 ³ , the flow is as shown in FIG. Also, 10 ³ ≦ Re ≦
In the case of 10 ^5, the flow is as shown in FIG.
In the case of> 10 ^5, the flow is as shown in FIG.

In this embodiment, the convex portion 39 corresponding to the cylindrical object 40 is formed in the side vent duct 37, and the conditioned air is blown into the duct opening by utilizing the difference in the flow of the fluid depending on the magnitude of the Reynolds number Re. The diffused wind spreads throughout, or the concentrated wind concentrated in the center of the duct. Specifically, the Reynolds number Re is "Re <10 ³ ".
By adjusting the wind speed of the conditioned air to a low speed so as to provide the diffused wind blown out from the entire opening of the side vent duct 37 as shown in FIG. FIG. 6 shows only the upper half of the side vent 27. On the other hand, by adjusting the conditioned air at high speed so that the Reynolds number Re becomes “10 ³ ≦ Re ≦ 10 ⁵ ”, FIG.
As shown in (1), concentrated wind is supplied near the center of the duct opening.

As described above, the air velocity u in the duct of the conditioned air
Can be changed by changing the rotation speed of the blower fan 14. In the following, the wind speed u in the duct is changed from 2 (m / s) to 8
(M / s) can be changed, and the diffused wind is supplied when the wind speed umin = 2 (m / s), and the concentrated wind is supplied when the wind speed umax = 8 (m / s). 39 settings (curvature radius L)
think about.

Assuming that the temperature of the conditioned air is about 0 to 20 ° C.,
The kinematic viscosity coefficient ν of air in this temperature range is ν = 0.1
It becomes 5 × 10 ^-4 . At this time, when umin = 2 (m / s), the curvature radius L that satisfies the condition Re ≦ 10 ³ of the diffusing wind is R
Since e = u × L / ν, “L ≦ 7.5 (mm)”. On the other hand, when umax = 8 (m / s), the condition of concentrated wind is 10 ³ ≦ R
The radius of curvature L satisfying e ≦ 10 ⁵ is “1.875 (m
m) ≦ L ≦ 187.5 (mm) ”. Therefore, the value of the radius of curvature L satisfying both conditions is “1.875 (m
m) ≦ L ≦ 7.5 (mm) ”.

That is, if the radius of curvature L of the convex portion 39 is set to a value within this range, the concentration as shown in FIG. The air is supplied from the outlet, and the cooling air can be intensively applied to the occupants. On the other hand, when the wind speed is switched to a low speed (umin) after a certain degree of cooling feeling is obtained, FIG.
The diffused wind as shown in FIG. 3A is supplied, and the cooling wind hits the whole body. As a result, optimal air blowing is realized, and the feeling during air conditioning can be improved. Further, when changing the spread of the conditioned air, it is not necessary to add a driving mechanism, a motor, a controller thereof, and the like unlike a louver, so that an increase in cost can be suppressed as much as possible.

FIG. 7 shows that the louver 34 is a side vent duct 3.
7 shows the conditioned air when provided in the opening 37a of FIG. 7, wherein (a) shows the case of the wind speed umin and (b) shows the case of the wind speed umax. In FIG. 7, the wind direction is obliquely upward because the louver 34 is obliquely upward, but the diffusion state and the concentration state of the conditioned air have not changed.

In the above-described embodiment, the side surfaces of the side vent ducts 37 are parallel as shown in FIG. 3B. However, even if they are not parallel as shown in FIGS. By changing the angle, a diffused wind and a concentrated wind can be formed. However, the one with the duct side parallel is most effective. The side vent duct 43 shown in FIG.
Has a duct shape that expands in the direction of the opening 43a, while the side vent duct 44 in FIG. 8B has a duct shape that narrows in the direction of the opening 44a.

The projection 39 shown in FIG. 3C protrudes in an arc shape inside the duct, and is formed so that the position of the center O of the arc substantially coincides with the side surface of the side vent duct 37. . However, the center O of the arc does not necessarily have to coincide with the side surface of the duct. For example, as shown in FIG. 9A, the center O is located outside the side surface of the duct, or as shown in FIG. It may be located inside the side. Also in this case, the effect is best exhibited when the center O coincides with the side surface of the duct as shown in FIG.

As can be seen from FIGS. 6 and 7, the spread of the conditioned air blown out when the diffused air is formed is as follows.
It depends to some extent on the shape of the duct located downstream of the projection 39. For example, when it is desired to increase the spread of the conditioned air, as shown in FIG. 10, the opening 45a may be formed such that the cross-sectional area of the opening 45a of the side vent duct 45 becomes larger as approaching the blowout opening 45b. .
In this way, in the case of the diffused air, the conditioned air having a width of about the cross-sectional area D1 of the opening 45b is blown out as shown in FIG. On the other hand, in the case of concentrated wind, FIG.
As shown in (b), the air is blown out with a duct cross-sectional area D2 at the portion of the convex portion 39. As a result, in the case of concentrated wind, the degree of concentration is more marked than in the case of diffused wind, and intensive cooling can be performed more effectively.

In the above embodiment, the side vent duct 37 has been described as an example, but the present invention can be similarly applied to other ducts.

In the correspondence between the embodiment described above and the elements of the claims, the intake door 13, the blower fan 14, the air mix door 19, the differential door 22,
The V / F door 25, the fan motor 26, the door actuators 27 to 30, and the controller 31 serve as a blowing means, such as a differential duct 20, a vent / foot duct 21, and a vent duct 2.
3, foot duct 24, side vent duct 37, 43
Reference numerals 45 to 45 denote ventilation ducts, and openings 37a and 43a to 45a.
Each constitute a blowout opening.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a vehicle air conditioner according to the present invention, and is an overall configuration diagram of the air conditioner.

2 is a perspective view showing a driver's seat 35 and a part of an instrument panel 36. FIG.

FIG. 3 is a diagram illustrating a side vent duct 37;
(A) is a perspective view of the side vent duct 37, (b) is a transverse cross-sectional view, and (c) is an enlarged view of a portion indicated by reference numeral A in (b).

4A and 4B are diagrams qualitatively illustrating a flow around a cylindrical object 40 when a cylindrical object 40 having a radius L is disposed in a fluid 41. FIG. 4A illustrates a Reynolds number Re of Re <10 ³ . In the case, (b) is 10 ³ ≦ Re ≦ 10 ⁵ , and (c) is Re.
> 10 ⁵ .

FIG. 5 shows Reynolds number Re and resistance coefficient C of cylindrical object 40.
It is a figure showing the relation with _D.

FIG. 6 is a diagram qualitatively showing the flow of the conditioned air in the side vent duct 37. FIG.
(B) shows the case of concentrated wind.

FIG. 7 is a diagram showing conditioned air when a louver is provided in an opening 37a of a side vent duct 37;
(A) shows the case of the wind speed umin, and (b) shows the case of the wind speed umax.

FIG. 8 is a view showing a modification of the side vent duct;
(A) shows a case where the duct has a shape extending toward the opening 43a, and (b) shows a case where the duct has a shape narrowing toward the opening 44a.

9A and 9B are diagrams showing a positional relationship between the center O of the convex portion and the side surface of the duct, wherein FIG. 9A shows a case where the center O is located outside the side surface of the duct, and FIG. Also shows the case where it is located inside.

FIGS. 10A and 10B are diagrams showing conditioned air when the cross-sectional area of the opening 45a of the side vent duct 45 is increased as approaching the opening 45b, where FIG. Is shown.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle air conditioner 13 Intake door 14 Blower fan 15 Evaporator 16 Heater core 19 Air mix door 20 Differential duct 21 Vent / foot duct 22 Differential door 23 Vent duct 24 Foot duct 25 V / F door 26 Fan motor 27-30 Door actuator 31 Controller 32 Center vent outlet 33 Side vent outlet 34 Louver 37, 43 to 45 Side vent duct 37a, 43a to 45a Opening 39 Convex portion 45b Outlet opening

Claims (3)

[Claims] 1. An air conditioner for a vehicle, comprising: a blowing unit capable of blowing conditioned air having at least two speeds of low speed and high speed; and a blowing duct for blowing the conditioned air blown by the blowing unit into a vehicle interior. An air conditioner for a vehicle, wherein a protrusion protruding inside the duct and having a substantially semicircular cross-section in the blowing direction is formed on at least a part of a duct inner peripheral surface of a blowing opening of the blowing duct. . 2. The vehicle air conditioner according to claim 1, wherein the Reynolds number of the conditioned air is about 1 when the wind speed is the low speed.
0 ³ or more and about 10 ⁵ or less, and when the wind speed is the high speed, the curvature radius and the wind speed of the projection are set so that the Reynolds number is about 10 ³ or less. . 3. The air conditioner for a vehicle according to claim 1, wherein a cross-sectional area of the blow-out opening is increased from the convex portion toward the opening.