JPH08164096A - Electric vacuum cleaner - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the noise in a wide frequency range generated by electric blowers. [Structure] A plurality of cavities 130 inclined in the circumferential direction are formed by a vibration-proof rubber 117, a fan casing 110, and a partition plate 118, and the cavities 130 are formed in a casing by a large number of holes 401 provided in the fan casing 110. Communicate with. Since the tilted cavity 130 can be lengthened, low frequency noise can also be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum suction type vacuum cleaner for household or industrial use.

[0002]

2. Description of the Related Art A vacuum suction type vacuum cleaner is provided with a centrifugal blower as a ventilation drive source in order to generate a high-speed air flow at a suction port. Since this blower generates a large amount of noise during operation, the noise of the electric vacuum cleaner also becomes large. For this reason, various attempts have been made to reduce noise in the blower, which is the sound source, or in the vicinity thereof. For example, JP-A-62-70695
An electric blower for an electric vacuum cleaner disclosed in Japanese Patent Publication No.
As shown in FIG.
01 and an air guide 801 are provided, a plurality of holes 802 are provided in the fan casing 110 so as to face the recess 803 provided in the antivibration rubber 117 arranged outside the fan casing 110, and the recess 803 and the hole 802 are formed. By configuring the resonance-type silencer, the sound of the harmonic component (blade sound) whose fundamental order is the frequency of the product of the number of blades of the impeller 101 and the number of rotations is reduced. Further, the fan casing 110 is provided with a plurality of positioning holes, and the pins protruding from the rubber vibration isolator 117 are used to form the recesses 803 and the holes 8.
The position of 02 is decided.

[0003]

Although such an electric blower can reduce the blade noise, it is difficult to reduce the noise of other wide frequency components. Also,
In order to configure the resonance type silencer, the fan casing and the vibration isolator are positioned in the circumferential direction so that the holes 802 and the recesses 80 are formed.
3 had to be matched, and the assembly work was troublesome.

An object of the present invention is to provide an electric vacuum cleaner which can reduce noise of a wide range of frequency components and is easy to assemble.

Another object of the present invention is to provide an electric vacuum cleaner which can achieve the above object with a small number of components.

[0006]

To achieve this object, one of the objects of the present invention is to provide an electric vacuum cleaner, in which an electric blower is supported by a main body case via a vibration-proof rubber, in a casing of the electric blower. By providing a plurality of holes at a position outside the outer periphery of the vehicle, by forming a recessed portion that is partitioned by a plurality of partitions in the anti-vibration rubber to cover the outside of the casing including the holes, each of the recesses It is characterized in that a plurality of hollow portions connected to the plurality of holes are formed.

Another aspect of the present invention is an electric vacuum cleaner equipped with an electric blower having an impeller and a diffuser with blades on the outer peripheral side of the impeller, and a silencer adapter abutting against the diffuser of the electric blower between each blade of the front diffuser. A recess is formed by forming a plurality of holes and a plurality of partitions provided so as to be continuous with the holes and corresponding to the blades of the diffuser, and the fan-casting covers the outside of the sound deadening adapter. It is characterized by having been made into a part.

Another invention is characterized in that the cavity is filled with a sound absorbing material.

[0009]

The main sound source of the electric vacuum cleaner is an electric blower, and among them, the impeller and the diffuser entrance are the main sound sources. The generated noise is transmitted to the rear through the diffuser, but penetrates the cavity formed by the casing and the anti-vibration rubber through multiple holes, and the sound waves cause interference in this cavity. Disappear, and the sound transmitted to the downstream side becomes smaller. This effect becomes more effective when the sound absorbing material is inside.

Since the cavity can be elongated by tilting it in the circumferential direction of the casing, a high silencing effect can be obtained even for low-frequency noise with a long wavelength.

Further, since the hollow portion is communicated with the inside of the fan casing by a plurality of holes, alignment is unnecessary.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional side view showing an embodiment of an electric blower unit in an electric vacuum cleaner according to the present invention, FIG. 2 is an external perspective view showing the entire electric vacuum cleaner, and FIG. 3 is a vertical sectional side view of a main body of the electric vacuum cleaner. 4, FIG. 4 is a sectional view taken along the line AA in FIG. 1, FIG. 5 is a partially enlarged view of the fan casing, and FIG. 6 is an external view of the impeller and the diffuser in the electric blower as seen from the axial direction.

As shown in FIG. 2, the vacuum cleaner body 201.
A hose 204 is rotatably attached to this, and a suction port 202 is attached to the tip of this hose 204 via a hose hand portion 205 and an extension pipe 203. Hose part 2
Reference numeral 05 denotes the operation switch unit 206 and the infrared light emitting unit 20.
7,208 are provided.

As shown in FIG. 3, the vacuum cleaner body 201 includes a lower case 307, an upper case 302, and a dust collecting lid 301.
It is configured by combining. A suction port 312 is provided in the dust collection lid 301 that can be opened and closed, and a dust collection bag 305 is installed inside the suction port 312 so as to communicate with the suction port 312. The dust collecting lid 301 is configured to keep confidentiality with the lower case 307 in a closed state, and forms a dust collecting chamber 313 accommodating the dust collecting bag 305 therebetween. Dust collection chamber 3
An electric blower chamber 308 is formed in the rear of 13 by the lower case 307 and the upper case 302. Electric blower room 3
An electric blower 303 serving as a ventilation drive source is housed in 08. The intake side of the electric blower 303 communicates with the dust collecting chamber 313 via the filter 304. The exhaust air of the electric blower 303 is configured to be discharged from the exhaust chamber through the filter to the outside through the exhaust port 309.

The electric blower 303 inside the vacuum cleaner body 201 will be described with reference to FIG. The electric blower 303 includes a centrifugal impeller 101, a diffuser 102 with vanes, a return guide 103 with vanes, and an electric motor 112. A fan casing 110 having an intake port 105 is press-fitted into the end bracket 107 so as to abut the diffuser 102 in the blower unit. As shown in FIGS. 4 and 5, the fan casing 110 has a large number of holes 401 having a diameter smaller than the thickness of the blade of the diffuser 102 having a plurality of blades. The electric blower 303 is elastically supported by the main body case via the anti-vibration rubber 117. The anti-vibration rubber 117 has an annular recess in which a plurality of partition plates 118 are inclined and integrated in the circumferential direction, and the fan casing 110 and the anti-vibration rubber 117 are provided.
The partition plate 118 and the partition plate 118 form a plurality of cavity portions 130, which are independently inclined in the circumferential direction, outside the plurality of holes 401.

Partition plate 11 formed on the lower case 307
The annular ribs 119a and 119b protruding from 9 and the disc-shaped rib 119c formed on the upper case 302 are
The electric blower 303 is supported in a vibration-proof (elastic) state by holding it around the vibration-proof rubber 117.

The number of blades 601 of the impeller 101 is 6,
The number of blades 602 of the diffuser 102 is 17, and the number of partition plates 118 of the anti-vibration rubber 117 is 17. A large number of holes 401 are concentrically arranged in two rows, and the total area (aperture ratio) of the holes 401 in the arrangement region is 30%.

Next, the air flow in the vacuum cleaner body 201 will be described. The airflow sucked together with the dust from the suction port 312 is the dust bag 305 and the filter 3
By 04, even dust of about 1 μm is removed. The partition plate 119 located behind the filter 304 has a plurality of holes 116, and the air flow passes through these holes 116 and the intake port 1
It is guided to the impeller 101 from 05. The high-speed airflow boosted by the impeller 101 is decelerated by the diffuser 102 with blades and the return guide 103 with blades and the pressure is recovered. Then, this airflow cools the inside of the electric motor 112 and is then discharged to the electric blower chamber 308.

The air flow discharged into the electric blower chamber 308 is
It is discharged from the exhaust port 309 to the outside through the exhaust chamber and the filter.

In such a vacuum cleaner, the impeller 1
The wind velocity of the airflow at the outlet of 01 is high at 100 m / s or more, and most of the noise is generated at the outlet of the impeller 101. The generated noise is generated by a plurality of holes 40
1 into the cavity 130 formed by the anti-vibration rubber 117, the fan casing 110, and the partition plate 118, and is silenced there by the silencing action as an expansion type silencer. At this time, since the plurality of holes 401 have a large aperture ratio,
Since it acts as an expansion type silencer, not as a resonance type silencer, which can only provide a silencing effect at a specific frequency, so that a silencing effect in a wide frequency range can be obtained.

Further, since the partition plate 118 is tilted in the circumferential direction to increase the length in the direction in which the sound is transmitted in the cavity 130, it is possible to mute sound waves of longer wavelength, that is, lower frequency components. You can

Further, since the hole 401 is made up of a plurality of small holes, the turbulence of the air flow is suppressed to reduce the pressure loss and the frequency of the generated air flow sound is increased to absorb the noise in the body, as compared with the case of providing a large hole. By making the frequency easy to operate, the structure is advantageous for noise reduction.

Further, since it is realized by changing the shape of the anti-vibration rubber 117, the increase of the manufacturing cost is slight.

Between the opening 116 of the partition plate 119 and the intake port 105 of the electric blower 201, a distance necessary to prevent deterioration of the air flow state due to a sudden change of the air flow is provided. It is possible to effectively use and secure the anti-vibration rubber 117 that has been raised to form the portion 130, and to lower the height of the annular ribs 119a and 119b to optimize the distance, the entire It is possible to prevent the shape from becoming large.

Furthermore, since each of the cavities 130 is independent, sound interference occurs independently in each of the cavities 130, and the size of the hole 401 is made smaller than the thickness of the vanes of the diffuser 102. Since many holes are arranged, the silencing effect does not change regardless of the position of each hole 401 in the circumferential direction. Therefore, the anti-vibration rubber 117 and the fan casing 1
Relative positioning in the circumferential direction of 10 is unnecessary, and a positioning mechanism such as a pin is not necessary, resulting in very good assembly workability.

If an impermeable sound absorbing material such as maltoprene is placed in the cavity 130, the sound deadening effect is further improved.
Moreover, since no airflow is generated through the hole 401, it is possible to further suppress an increase in pressure loss.

FIG. 7 shows an example of the sound deadening effect of this embodiment. The horizontal axis represents frequency, and the vertical axis represents silence volume. This is the volume of noise when impermeable maltoprene is inserted into the cavity 130. In the state in which the partition plate 118 is not provided, the frequency at which a large silencing effect is obtained is in the region of 5 kHz or higher, but by dividing the cavity 130 by the partition plate 118 and making it elongated, the frequency is relatively high even in the frequency region of 1 kHz or lower. The muffling effect is obtained.

FIG. 9 shows a modified embodiment of the vibration-proof rubber in the electric vacuum cleaner according to the present invention, and is a sectional view taken from the same viewpoint as FIG. FIG. 9 shows that in the vibration-proof rubber 117 according to this embodiment, the number of partition plates 118 that partition the recess to form the cavity 130 is smaller than the number of diffuser blades 602. Other configurations are similar to those shown in FIG. Although not shown here, the fan casing 110, the anti-vibration rubber 117, and the partition plate 118.
A sound absorbing material is put in the cavity 130 formed by.

This embodiment is slightly inferior to the above-mentioned embodiment in the noise reduction effect, but has the advantage that the number of partition plates 118 provided on the vibration-proof rubber 117 is small, so that the weight can be reduced.

FIG. 10 is a partial sectional view of an electric blower, showing another embodiment of means for forming a cavity for noise reduction in an electric vacuum cleaner according to the present invention. The electric blower 303 includes a centrifugal impeller 101, a diffuser 102 with blades, a return guide 103 with blades, and an electric motor 112. A muffling adapter 1004 is provided in the blower unit so as to come into contact with the diffuser 102.

The muffling adapter 1004 is used for the diffuser 1
Partition disk 1 in which a plurality of holes 1005 (corresponding to the holes 401 in the above-described embodiment) are formed in the portion abutting 02.
001, a number of protruding ribs 1002 (corresponding to the partition plate 118) equal to the number of diffuser blades formed integrally with the partition disk 1001, and an annular rib 1003 formed on the inner peripheral side thereof. Prepare

The fan casing 110, which is press-fitted into the end bracket 107, presses the muffling adapter 1004 toward the diffuser side, and at the same time, the muffling adapter 1004.
4, the number of cavities 130 equal to the number of blades of the diffuser 102 is formed so as to cover the circumference of 4. The form of the cavity 130 is the same as that shown in FIG. The sound absorbing material 131 is filled in the cavity 130.

The electric blower 303 configured as described above
Since it is difficult to form a gap in the contact portion between the partition disk 1101 and the diffuser 102, airflow leakage on both sides of the blades of the diffuser 102 is reduced, and performance deterioration due to leakage can be reduced. Therefore, the average suction performance of the electric blower 303 can be increased.

Further, since the position of the muffling adapter 1005 is determined by the fan casing 110, the diffuser 102, the muffling adapter 1005, and the fan casing 110 are placed in this order on the end bracket 107, and the fan casing 110 is wrapped around them.
Since it can be assembled by press-fitting into the end bracket 107, the assembling work becomes very easy.

The effect of noise reduction can be obtained in the same manner as in the above-mentioned embodiments.

Further, the anti-vibration rubber 11 in each embodiment.
Similar effects can be obtained even if 7 is formed of a rubber material having a high foam density and the cavity 130 is filled with a rubber material having a foam density.

[0037]

As described above, according to the present invention, a casing is covered with a vibration-proof rubber having an annular recess sectioned by a plurality of partitions to form a sound deadening cavity communicating with the inside of the casing through a plurality of holes. Therefore, it is possible to reduce the noise of a wide range of frequency components, and it becomes unnecessary to align the holes with the individual holes, which facilitates the assembling work.

Further, an electric blower in which a sound deadening adapter, which is in contact with the sound deadening diffuser, is covered with fan casings to form a hollow portion for sound deadening has the same effect.

With such a structure, it is possible to obtain an excellent silencing effect with a small number of parts.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of an electric blower in an electric vacuum cleaner according to the present invention.

FIG. 2 is an external perspective view showing the entire electric vacuum cleaner according to the present invention.

FIG. 3 is a vertical sectional side view of the main body of the electric vacuum cleaner shown in FIG.

FIG. 4 is a cross-sectional view taken along the line AA of FIG.

FIG. 5 is a partially enlarged plan view of a fan casing.

FIG. 6 is an external view of the impeller and the diffuser of the electric blower as viewed in the axial direction.

FIG. 7 is a sound deadening characteristic diagram of the electric vacuum cleaner according to the present invention.

FIG. 8 is a cross-sectional side view of a portion of an electric blower and a vibration isolating rubber of a conventional example.

FIG. 9 is a partial cross-sectional view showing another embodiment of the electric vacuum cleaner according to the present invention.

FIG. 10 is a partial cross-sectional view of an electric blower showing still another embodiment of the electric vacuum cleaner according to the present invention.

[Explanation of symbols]

101 ... Impeller, 102 ... Diffuser, 103 ... Return guide, 110 ... Fan casing, 117 ... Anti-vibration rubber, 118 ... Partition plate, 130 ... Hollow part, 201 ... Vacuum cleaner book, 303 ... Electric blower, 401 ... Hole .

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Taiji Tajima, Taiji Tajima, 502 Jinritsu-cho, Tsuchiura-shi, Ibaraki Machinery Research Laboratories, Hiritsu Seisakusho Co., Ltd. (72) Inventor Takahiro Nakai, Electric Appliances Division, Hitachi, Ltd. (1-1) 1-1-1, Higashitaga-cho, Hitachi, Hitachi, Ibaraki Prefecture Incorporated, Hitachi, Ltd. Electric Appliances Division, Taga Headquarters (72) Inventor, Fumio Joraku Ibaraki 1-1 1-1 Higashitaga-cho, Hitachi, Ltd. Inside Taga Headquarters, Electric Equipment Division, Hitachi, Ltd.

Claims (10)

[Claims] 1. An electric vacuum cleaner for supporting an electric blower on a main body case via a vibration-proof rubber, wherein a plurality of holes are provided at a position outside an outer periphery of an impeller of a casing of the electric blower, and the vibration-proof rubber is provided. A plurality of cavities each of which is connected to the plurality of holes are formed by the recess by forming a recessed portion that is partitioned by a plurality of partitions to cover the outside of the casing including the hole. Vacuum cleaner. 2. The vacuum cleaner according to claim 1, wherein a sound absorbing material is filled in the concave portion of the vibration isolating rubber. 3. An electric cleaner having an impeller, a fan-equipped diffuser on the outer peripheral side of the impeller, and an electric vacuum cleaner having a vibration-proof rubber for supporting the electric blower, wherein each of the diffusers is provided in a casing of the electric blower. A plurality of holes are provided so as to be located between the blades of the diffuser, and an anti-vibration rubber having an annular concave portion divided by a plurality of partitions corresponding to the diffuser blades is formed to cover the outside of the casing including the holes and to form the concave portion. The vacuum cleaner is characterized in that a hollow portion is formed so as to respectively connect to the plurality of holes. 4. The vacuum cleaner according to claim 3, wherein a sound absorbing material is filled in the concave portion of the vibration isolating rubber. 5. The electric vacuum cleaner according to claim 1, wherein the plurality of holes formed in the casing are opened from the direction of the diffuser. 6. The electric vacuum cleaner according to claim 1, wherein the partition is formed so as to be inclined in the circumferential direction, and the cavity portion that is inclined in the circumferential direction is formed therebetween. 7. The electric cleaning system according to claim 1, wherein the vibration-proof rubber is formed of a rubber material having a high foam density and the cavity is filled with a rubber material having a low foam density. Machine. 8. An electric vacuum cleaner for supporting an electric blower on a main body case via a vibration-proof rubber, wherein a plurality of holes are provided at a position outside an outer periphery of an impeller of a casing of the electric blower, and the vibration-proof rubber is provided. By forming an annular concave portion partitioned by a plurality of partitions inclined in the circumferential direction to cover the outside of the casing including the hole, a plurality of inclined cavity portions each of which is connected to the plurality of holes by the concave portion An electric vacuum cleaner characterized by being formed. 9. An electric vacuum cleaner equipped with an electric blower having an impeller and a diffuser with blades on the outer peripheral side of the electric blower, wherein a plurality of silencer adapters abutting against the diffuser of the electric blower are provided between the respective blades of the front diffuser. And a concave portion separated by a plurality of partitions provided corresponding to the diffuser blades so as to be continuous with the hole, and the outer side of the sound deadening adapter is covered by fan casing to make the hollow portion into a sound deadening hollow portion. An electric vacuum cleaner characterized in that. 10. The electric vacuum cleaner according to claim 9, wherein a sound absorbing material is filled in the recess of the sound deadening adapter.