JPS609944B2 - Vehicle air conditioning duct - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air conditioning duct for a vehicle, and more particularly to an air conditioning duct for a vehicle equipped with a sound absorbing structure suitable for use in a railway vehicle equipped with a roof-mounted central air conditioner.

A conventional air conditioning duct for a vehicle generally has a structure as shown in FIGS. 1 and 2.

That is, an air conditioner 2 installed on the roof near the center of the vehicle 1 is connected to a cold air duct 4 installed in the ceiling of the vehicle 1 through a cold air outlet 3, and the cold air supplied by the air conditioner 2 is connected to the cold air duct 4 installed on the ceiling of the vehicle 1. is blown into the passenger compartment 6 through blow-off grilles 7a and 7b provided on the lower surface of the cold air duct 4.
More specifically, the air conditioner 2 takes in circulating air from the vehicle through the return grill 14 and the return port 15,
On the other hand, fresh air from outside is taken in through an outside air intake grill 10, cooled by heat exchange with a cooler 11, and then supplied to a cold air duct 4 through a cold air outlet 3 by a fan 12. . Looking at each outlet grill of the cold air duct 4 at this time, the center outlet grill 7a and the end outlet grill 7b
Since the former is closer to the cold air outlet 3, it will blow out more cold air, so we want to make the air volume of both the same as much as possible so that the temperature in the cabin is uniform throughout. A shielding plate 5 is provided in the cold air duct immediately below the cold air outlet 3 to prevent the cold air from the cold air outlet 3 from directly reaching the central outlet grille 7a. A problem with such vehicle air conditioners and air conditioning duct equipment is how to prevent the noise generated in the air conditioner 2 from propagating into the vehicle interior.

Figure 1: In the conventional air conditioning duct shown in Figure 2, sound-absorbing material is used inside the cold air duct 4 and on the shielding plate 5 to prevent the fluid noise generated by the fan 2 from being propagated together with the flow of cold air. However, in the conventional air conditioning duct, there is a gap between the shielding plate 5 and the cold air duct turtle, and the length of the shielding plate 5 is not sufficient, so the part directly under the air conditioner 2 Sufficient sound absorption effect cannot be obtained,
Therefore, as shown in FIG. 3, the distribution of the noise level inside the vehicle is disadvantageous in that the area directly below the air conditioner 2 has a high noise level. The purpose of the present invention is to overcome the above-mentioned drawbacks and
To provide an air conditioning duct for a vehicle having a function of reducing the noise level directly below an air conditioner. The present invention takes advantage of the property that the noise level decreases according to the distance from the sound source, and in order to reduce the noise level directly below the air conditioner, the cold air duct has a two-tier structure, and a partition is used to separate the upper and lower tiers. The length of the plate is approximately half or more of the total length of the vehicle.

A specific embodiment of the present invention will be explained with reference to FIG. 4 and FIG. It is connected to the cold air duct 24 which is located in the air, and is also connected to the passenger compartment 26 through a return port 35.

The cold air duct 24 is divided into an upper cold air duct 24a and a lower cold air duct 2 by a partition plate 25 provided over approximately half of the total length of the vehicle 21, centered on the vicinity directly below the air conditioner 22.
It is divided into 4b and 4b. And upper cold air duct 24a
Sound-absorbing materials 28 and 29 are attached to the duct wall 33 and partition plate 25 forming the lower cold air duct 24b, respectively. Next, regarding the air flow in this embodiment, the circulating air taken in through the IJ turn grill 34 and the return port 35 and the fresh air taken in through the outside air intake grill 30 are mixed into the cooler 31. It is cooled by exchanging heat with.

The cooled air is supplied by the fan 32 to the upper cold air duct 24a through the cold air outlet 23, flows in the front and back direction of the vehicle as shown by the arrow, reaches the cold air duct 241 without the partition plate 25, and a part of the air is The cold air flows to the guest room 2SI via the end outlet grille 27b, and the remaining cool air returns to the lower cold air duct 24b and flows to the guest room 26 via the center outlet grille 27a. According to this embodiment, the noise propagation distance from the cold air outlet 23 to the center outlet 27a and the noise propagation distance to the end outlet 27b are controlled by the cutting plate 25 installed over about half of the total length of the vehicle. Since the distances are approximately equal, the distribution of the noise level at each location in the car is as shown by the solid line in FIG.

A in FIG. 6 is the noise level in the upper cold air duct 24a immediately below the side air outlet 23, and D is the noise level inside the vehicle below the hypothetical central air outlet 27a.
In reality, the sound coming from the front end of the partition plate 25 and the sound coming from the rear end of the partition plate 25 overlap in the vicinity of the central outlet grille 27a, so the noise level in the center of the car is similar to point E. In other words, according to this embodiment, the noise level immediately below the central air conditioner is reduced by approximately B compared to the conventional system, and the distribution of the noise level inside the vehicle is made more uniform.

Furthermore, in this embodiment, an example was explained in which the length of the partition plate 25 is approximately half of the total length of the vehicle, but if the length of the partition plate is further increased, the noise level directly under the air conditioner will further decrease, so It is also possible to almost eliminate the difference in noise level from the end portion.

FIG. 7 shows another embodiment of the present invention in which the cold air duct has a double-tube structure instead of being partitioned into an upper stage and a lower stage. According to this embodiment, compared to the partition plate 25 of FIG. Inner cylinder duct wall 4
Since the circumferential length of the cross section is longer in No. 3, the area of the sound absorbing material 44 is larger than that of the sound absorbing material 29, which has the effect of increasing the sound absorbing ability accordingly. FIG. 8 shows still another embodiment of the present invention, in which the cold air duct is structured to be partitioned into an inside and an outside. According to this embodiment, an inner duct wall 47 connects a ceiling 49 and a duct wall 33. Because of this, the duct wall 3
This has the secondary effect of increasing the rigidity of duct wall 3 and preventing vibrations of the duct wall caused by air flow.

FIG. 9 shows an air conditioning duct structure in which air conditioners 22a and 22b are respectively installed on the roofs of both ends of a vehicle as a modification of the present invention; the basic idea is the same in this case as well. The length of the passenger room served by the air conditioning platform 22a from the cold air outlet 23 of one air conditioner 22a (in this example, two air conditioners are installed in one vehicle, so each vehicle is half the length of the vehicle) It will be in charge of air conditioning for the length of the guest rooms.

), it is sufficient to provide the partition plate 25 in the cold air duct over half the length or more.According to the present invention, the noise propagation distance from the air conditioner, which is the sound source, to the center of the car interior is Since the distance of noise propagation to the end of the vehicle can be made approximately equal, the noise level directly below the air conditioner can be reduced and the noise level inside the vehicle can be made uniform.

[Brief explanation of the drawings] Figure 1 is a side sectional view of a vehicle equipped with a conventional vehicle air conditioning duct, Figure 2 is a sectional view of a conventional vehicle air conditioning duct, and Figure 3 is a sectional view of a vehicle equipped with a conventional vehicle air conditioning duct.
Figure 4 is a distribution diagram of the noise level inside a vehicle installed with a conventional vehicle air conditioning duct, Figure 4 is a side sectional view of a vehicle installed with the vehicle air conditioning duct of the present invention, and Figure 5 is a vehicle noise level distribution diagram of a vehicle equipped with a conventional vehicle air conditioning duct. FIG. 6 is a cross-sectional view of one embodiment of an air conditioning duct, FIG. 6 is a distribution diagram of the noise level inside a vehicle installed with the vehicle air conditioning duct of the present invention, and FIGS. 7 and 8 are cross-sectional views of an embodiment of the vehicle air conditioning duct of the present invention. FIG. 9 is a side sectional view of a vehicle in which the vehicle air conditioning duct of the present invention is installed. 22... Air conditioner L 23... Side air outlet, 24... Cold air duct, 25... Partition plate, 26...
Guest room, 27a... Central outlet grill, 27b...
・Car end outlet grille ``28... Convex sound absorbing material, 29...
...Sound absorbing material, 33...Duct wall. Younger brother's figure 2 figure 3 Hair 4 figure S figure fist figure Younger brother 7 figure Praise figure younger brother's figure

Claims (1)

[Scope of Claims] 1. A duct wall that is connected to an air conditioner installed in the upper part of the vehicle via a cold air outlet and forms a cold air flow path, a cold air outlet grill for blowing the cold air into the passenger compartment, and A vehicle air-conditioning duct configured with sound-absorbing material affixed to a duct wall, characterized in that the air-conditioning duct is divided into an upper and a lower stage over at least half of the length of the vehicle by a partition plate to which sound-absorbing material is affixed. Air conditioning duct for vehicles. 2. A patent characterized in that the air conditioning duct is formed into a double duct structure of an inner tube and an outer tube, the inner tube duct is connected to a cold air outlet of an air conditioner, and the outer tube duct is provided with a cold air outlet grill. A vehicle air conditioning duct according to claim 1. 3 The ceiling of the vehicle and the duct wall are connected by two partition plates equipped with sound-absorbing material, the cold air intake port of the air conditioner is connected between the two partition plates, and a cold air outlet grill is provided on the outside of both partition plates. An air conditioning duct for a vehicle according to claim 1, characterized in that: