JPH08225014A - Centrifugal type blower for automobile - Google Patents

Abstract

PURPOSE: To provide a centrifugal type air blower for vehicle which can reduce the noise of a low sound less than a specific Hz value, without making the structure complicated and of a high cost, by only converting the form of the existing blower unit minutely. CONSTITUTION: By paying the attension to provide a space (an atmosphere communicating housing part 11) to a suction passage wall surface 10, a specific capacity of atmosphere communicating housing part 11 communicating in the atmosphere is formed integrally to a blower unit 2, to the suction passage wall surface part 10 opposing to an inner air suction port 5 of the blower unit 2, and a sound absorbing material 14 is housed in the atmosphere communicating housing part 11, as well as a through hole 13 communicating the atmosphere communicating housing part 11 and a suction passage 9 is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal blower for an automobile using a sirocco fan or the like, and more particularly to a centrifugal blower for an automobile capable of reducing noises caused by blowing operation.

[0002]

2. Description of the Related Art In a conventional centrifugal blower for an automobile such as a sirocco fan, noises caused by air blow operation are caused by turbulent flow and wind noise at the bellmouth at the inside air intake port and the outside air intake port or the intake passage. There are the wind noise of the inside / outside air switching door, the noise of passing through the suction passage, the wind noise of the outlet end (discharge port), and the noise of the impeller.

In recent years, the inside / outside air switching door, which has conventionally been one, has been replaced with an inside air intake door and an outside air intake door.
By reducing the suction resistance by increasing the number of sheets, it is possible to increase the air volume by making the cross-sectional area of the passage large and at the same time, the noise is also released by releasing the noise to both the inside air intake port and the outside air intake port. However, there is a problem that the cost increases due to the increase in the number of parts due to the double door structure.

As a known technique, Japanese Patent Laid-Open No. 61-22
In No. 0911 and JP-A-62-198515, a sound absorbing material is lined on the inner wall of the duct. JP-A-2-157
499, JP-A-2-227599, JP-A-3-12
In No. 1298, a porous material is used for the suction side casing and the like. Japanese Unexamined Patent Publication No. 5-172100 employs a double structure of a porous body and an air layer. JP-A-6-
In No. 10891, a sound absorbing material is attached to the discharge port of the housing.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems. For example, in a structure having one inside / outside air switching door, it is possible to reduce particularly low noise of 1 KHz or less. An object is to provide a centrifugal blower for an automobile.

It is another object of the present invention to provide a centrifugal blower for an automobile, which has a simple structure and is low in noise, not a complicated and costly structure.

Another object of the present invention is to provide a centrifugal blower for an automobile, which requires only a slight modification of the existing blower unit.

[0008]

That is, the present invention focuses on providing a space portion (atmosphere communicating storage portion, bag-shaped storage portion, bag-shaped muffler portion) of a predetermined volume in the wall surface of the suction passage. One aspect of the invention is to provide a blower unit in which an inside air intake port and an outside air intake port and discharge ports communicating with the inside air intake port and the outside air intake port through an intake passage are formed, and by rotating in the blower unit. A centrifugal blower for an automobile, comprising: an impeller for sucking air from the inside air suction port or the outside air suction port and discharging the air from the discharge port through the suction passage, the blower unit comprising: On the suction passage wall surface portion facing the inside air suction port,
An air communication storage portion having a predetermined capacity that communicates with the atmosphere is integrally formed with the blower unit to form a through hole that connects the air communication storage portion and the suction passage, and at the same time, a sound absorbing material is provided in the air communication storage portion. It is a centrifugal blower for an automobile, which is characterized by containing.

The second aspect of the present invention focuses on forming a bag-shaped storage portion instead of the atmosphere communication storage portion of the first aspect of the present invention, and the inside air suction port and the outside air suction port are connected through the suction passage. A blower unit having an opening formed with a discharge port communicating with the inside air intake port and the outside air intake port, and by rotating in the blower unit, air is sucked from the inside air intake port or the outside air intake port and through the suction passage. A centrifugal blower for an automobile having an impeller for discharging the air from the discharge port, wherein a bag-shaped storage part having a predetermined capacity is provided on a wall surface of the suction passage facing the inside air suction port of the blower unit. Is integrally formed with the blower unit to form a through hole which connects the bag-shaped storage portion and the suction passage with each other, and the bag-shaped storage part is formed. An automobile for a centrifugal blower, characterized in that housing the sound absorbing material to the part.

A third aspect of the present invention focuses on forming a bag-shaped muffler portion in place of the air communication storage portion of the first invention and the bag-shaped storage portion of the second invention. A blower unit having an opening formed with a suction port and a discharge port communicating with the inside air suction port and the outside air suction port through a suction passage, and the inside air suction port or the outside air suction port by rotating in the blower unit. A centrifugal blower for an automobile, comprising: an impeller for sucking air and discharging the air from the discharge port through the suction passage, the suction passage wall surface facing the inside air suction port of the blower unit. In the blower unit, a bag-shaped muffler portion having a predetermined capacity is formed integrally with the blower unit. An automobile for a centrifugal blower, characterized in that the formation of the through-hole that communicates and.

[0011]

In the centrifugal blower for an automobile according to the present invention, a space portion (atmosphere communication storage portion, bag-shaped storage portion, bag-shaped muffler portion) having a predetermined volume is provided on the wall surface of the suction passage facing the inside air inlet. Therefore, due to the diffusion of sound waves in this space, especially in the low-pitched part (frequency is 1 KHz or less)
It is possible to realize low noise, and there is an advantage that the blower unit can be easily additionally processed with a simple structure.

In particular, according to the first aspect of the invention, since the space is the atmosphere communicating / accommodating portion, a part of the noise in the suction passage can be efficiently diffused into the atmosphere from the inside air suction port, and at the same time, the atmosphere can be diffused. The sound absorbing material housed in the communication housing can efficiently absorb sound energy.

In particular, according to the second aspect of the invention, since the space portion is a bag-shaped storage portion, sound waves can be diffused in the bag-shaped storage portion, and the sound absorbing material stored in the bag-shaped storage portion improves efficiency. Sound energy can be absorbed.

In particular, according to the third aspect of the invention, since the space is the bag-shaped muffler, the sound absorbing material is not used.
Noise reduction can be achieved by a simple configuration in which only sound waves are diffused in the bag-shaped muffler portion.

[0015]

[Embodiment] Next, a first embodiment of the present invention (first invention)
The centrifugal blower 1 for an automobile according to FIG. 1 will be described with reference to FIGS. FIG. 1 is a perspective view of an entire main part of the automobile centrifugal blower 1, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 3 is a side view showing a mounted state of the automobile centrifugal blower 1. The automotive centrifugal blower 1 includes a blower unit 2, an inside / outside air switching door 3, and an impeller 4.

The blower unit 2 is made of synthetic resin, for example, and is constituted by an inside / outside air switching box 2A and a scroll portion 2B at the bottom of the inside / outside air switching box 2A. The inside / outside air switching box 2A is formed with an inside air suction port 5 and an outside air suction port 6 adjacent to each other, and a discharge port 7 is formed in the scroll portion 2B.

The inside / outside air switching door 3 is provided with a switching shaft 8
One of the inside air intake port 5 and the outside air intake port 6 is opened and closed by rotating around.

The discharge port 7 communicates with the inside air suction port 5 and the outside air suction port 6 through a suction passage 9.

The impeller 4 rotates in the scroll portion 2B at the bottom of the blower unit 2 to suck air from the inside air intake port 5 or the outside air intake port 6 and to discharge the air from the discharge port 7 through the intake passage 9. Discharge.

In particular, as shown in FIG. 2, the inside air intake port 5
To the suction passage wall surface portion 10 facing the
1 is formed integrally with the inside / outside air switching box 2A of the blower unit 2. The atmosphere communication storage unit 11 communicates with the atmosphere through the atmosphere opening 12 and has a predetermined capacity. The atmosphere communication storage unit 11 and the suction passage 9 are connected to each other.
A through hole 13 that communicates with and is formed.

As shown in FIG. 1, the lateral length of the atmosphere communicating / accommodating portion 11 is equal to or longer than the widthwise size of the inside / outside air switching door 3 of the inside air inlet 5. Further, the width H of the atmosphere communication storage portion 11 (see FIG. 2)
Is preferably large so as to move away from the suction passage 9.

The sound absorbing material 14 is housed in the atmosphere communication housing portion 11, and the upper portion of the sound absorbing material 14 is fixed by the fixing ribs 15. As the sound absorbing material, a foam material or other porous material can be adopted, and for example, urethane sponge or the like can be used, and the sound absorbing material can be used as a sealing material at a predetermined density in the atmosphere communication storage portion 11. Can also be stored.

The sound absorbing material 14 may be projected slightly outward (upward) from the atmosphere opening 12, and the gap L between the upper edge of the through hole 13 and the upper end of the sound absorbing material 14 (from the through hole 13). It is desirable that the distance to the atmosphere) be as small as possible in consideration of sealing properties.

As shown in FIGS. 2 and 3, it is desirable that the atmosphere opening 12 be oriented toward the partition wall 18 between the vehicle compartment 16 and the engine compartment 17. That is,
Since the rubber material 19, the sound absorbing material 20, and the iron plate 21 are provided in multiple layers in the partition wall 18 from the inside, it is possible to absorb the noise diffused to the outside from the atmosphere opening 12.

In the centrifugal blower 1 for an automobile having such a structure, the impeller 4 is driven to take in air from the inside air intake port 5 or the outside air intake port 6, passes through the intake passage 9, and is centrifugally discharged from the impeller 4 to the discharge port 7. Is ejected.

In particular, as shown in FIG. 2, since the atmosphere communication storage portion 11 and the sound absorbing material 14 are provided in the portion (intake passage wall surface portion 10) facing the inside air suction port 5 facing the passenger compartment 16, the atmosphere is stored. The sound wave diffuses in the communication storage unit 11. Further, the sound wave escapes into the atmosphere, and the sound absorbing material 14
The sound waves are absorbed by.

Therefore, it is possible to reduce the noise generated in the suction passage 9 portion from the inside air suction port 5 to the suction passage wall surface portion 10 and to reach the suction passage wall surface portion 10, and particularly, from the inside air suction port 5 to the passenger compartment 16 side. The noise transmitted to the can be attenuated.

Further, FIG. 4 is a graph showing the relationship of the noise level with respect to the frequency of the sound wave, and it can be seen that particularly low frequencies of 1 KHz or less are reduced as compared with the conventional case.

FIG. 5 is a sectional view of an essential part of a centrifugal blower 30 for an automobile according to a second embodiment (second invention) of the present invention, which is a blower unit 2 (inside / outside air switching box 2).
A bag-shaped storage portion 31 is formed on the suction passage wall surface portion 10 of A) in place of the atmosphere communication storage portion 11, and is communicated with the suction passage 9 through the through hole 13.

The sound absorbing material 14 is stored in the bag-shaped storage portion 31. The blower unit 2 shown in FIG. 1 as a whole has a structure in which the bag unit 2 is divided into two parts.
The sound absorbing material 14 can be stored in the unit 1.

A centrifugal blower 30 for an automobile having such a structure
Also in the above, the sound wave is diffused in the bag-shaped storage portion 31 and is absorbed by the sound absorbing material 14, so that the blowing capacity is not lowered as compared with the centrifugal blower 1 for an automobile (FIGS. 1 to 3). It is possible to realize noise reduction.

FIG. 6 is a sectional view of an essential part of a centrifugal blower 40 for an automobile according to a third embodiment (third invention) of the present invention, which shows a blower unit 2 (inside / outside air switching box 2).
A bag-shaped muffler portion 41 is formed on the suction passage wall surface portion 10 of A) in place of the atmosphere communication storage portion 11 or the bag-shaped storage portion 31, and is communicated with the suction passage 9 through a through hole 42 corresponding to the through hole 13. .

The through hole 42 has a smaller diameter than the through hole 13 to enhance the muffler effect. However, the sound absorbing material 14 is not housed in the bag-shaped muffler portion 41.

A centrifugal blower 40 for an automobile having such a structure
Also in the above, noise can be reduced by the sound wave diffusing action in the bag-shaped muffler portion 41, and the cost is reduced because the sound absorbing material 14 is not used.

The present invention can realize low noise while suppressing the cost by applying the inside / outside air switching door 3 to a single blower, but if there is no cost problem, a double door blower is provided. It can also be applied to.

[0036]

As described above, according to the present invention, a space portion such as an atmosphere communication storage portion, a bag-shaped storage portion or a bag-shaped muffler portion is formed especially on the wall surface of the suction passage facing the inside air inlet. The sound wave can be effectively diffused and the sound wave absorbing function can be exhibited by providing a sound absorbing material in this space. Further, the structure can be simplified and the noise reduction can be realized at low cost as compared with the conventional noise reduction shape.

[0037]

[Brief description of drawings]

FIG. 1 is an overall perspective view of a main part of an automobile centrifugal blower 1 according to a first embodiment (first invention) of the present invention.

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

FIG. 3 is a side view showing a mounted state of the automobile centrifugal blower 1.

FIG. 4 is a graph showing the relationship between the frequency of a sound wave and the noise level.

FIG. 5 is a cross-sectional view of essential parts of a centrifugal blower for an automobile 30 according to a second embodiment (second invention) of the present invention.

FIG. 6 is a cross-sectional view of essential parts of a centrifugal fan 40 for an automobile according to a third embodiment (third invention) of the present invention.

[Explanation of symbols]

1 Automotive Centrifugal Blower 2 Blower Unit 2A Inside / Outside Air Switching Box of Blower Unit 2 2B Scroll of Blower Unit 2 Inside / Outside Air Switching Door 4 Impeller 5 Inside Air Suction Port 6 Outside Air Suction Port 7 Discharge Port 8 Switching Axis 9 Suction Passage 10 Walls of Suction Passage 11 Atmosphere Communication Storage 12 Atmosphere Opening 13 Through Hole 14 Sound Absorbing Material 15 Fixing Rib 16 Car Room 17 Engine Room 18 Partition Wall 19 Rubber Material 20 Sound Absorbing Material 21 Iron Plate 30 Centrifugal Blower for Car 31 Bag-shaped Storage Part 40 Centrifugal blower for automobile 41 Bag-shaped muffler part 42 Through hole L Distance between upper end edge of through hole 13 and upper end of sound absorbing material 14 (distance from through hole 13 to the atmosphere) H Atmosphere communication storage part 11 width

Claims (3)

[Claims] 1. An inside air intake port and an outside air intake port,
A blower unit having an opening formed with a discharge port communicating with the inside air suction port and the outside air suction port through a suction passage, and by sucking air from the inside air suction port or the outside air suction port by rotating in the blower unit. An impeller for discharging this air from the discharge port through the suction passage, and a centrifugal blower for an automobile, comprising: a suction passage wall surface portion of the blower unit, the suction passage wall surface portion facing the inside air suction port; An air communication storage portion having a predetermined capacity is formed integrally with the blower unit so as to communicate therewith, a through hole is formed to connect the air communication storage portion and the suction passage, and a sound absorbing material is provided in the air communication storage portion. A centrifugal blower for automobiles, which is characterized by being stored. 2. An inside air intake port and an outside air intake port,
A blower unit having an opening formed with a discharge port communicating with the inside air suction port and the outside air suction port through a suction passage, and by sucking air from the inside air suction port or the outside air suction port by rotating in the blower unit. An impeller for discharging the air from the discharge port through the suction passage, and a centrifugal blower for an automobile, comprising: a suction passage wall surface portion facing the inside air suction port of the blower unit; A bag-shaped storage portion having a capacity is formed integrally with the blower unit, a through hole that connects the bag-shaped storage portion and the suction passage is formed, and a sound absorbing material is stored in the bag-shaped storage portion. A centrifugal blower for automobiles. 3. An inside air intake port and an outside air intake port,
A blower unit having an opening formed with a discharge port communicating with the inside air suction port and the outside air suction port through a suction passage, and by sucking air from the inside air suction port or the outside air suction port by rotating in the blower unit. An impeller for discharging the air from the discharge port through the suction passage, and a centrifugal blower for an automobile, comprising: a suction passage wall surface portion facing the inside air suction port of the blower unit; A centrifugal blower for an automobile, characterized in that a bag-shaped muffler portion having a capacity is formed integrally with the blower unit, and a through hole that connects the bag-shaped muffler portion and the suction passage is formed.