JP3058764B2 - Electric vacuum cleaner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum cleaner capable of reducing vibration and noise during operation.

[0002]

2. Description of the Related Art An electric blower built in a vacuum cleaner main body includes:
A fan is mounted on the rotating shaft of the motor, and the fan is covered with a fan cover. Further, both ends of the rotary shaft are supported by bearings, and one of the bearings is disposed in a bearing fitting protrusion formed at the center of the bottom wall of the motor case in which the stator and the rotor are housed. Are arranged at the fan-side opening of the motor case.

[0003] A bearing fitting projection of the electric blower is sandwiched between support ribs formed on the main body of the cleaner through an exhaust-side anti-vibration rubber fitted to the outside thereof, and a fan cover of the electric blower is provided. The electric blower is supported in the cleaner main body by bringing the suction-side anti-vibration rubber fitted on the outer side of the peripheral portion into contact with the partition wall formed in the cleaner main body from the thrust direction. The two rubbers are used to maintain the airtightness of the space between the support ribs and the partition walls and to suppress vibrations during operation of the electric blower from being transmitted to the cleaner body.

[0004] The air sucked by the blowing action caused by the rotation of the fan of the electric blower is filtered by a dust collecting filter, and the filtered air passes through the fan, passes through the inside of the motor case, and reaches the bottom of the case. The air is exhausted from the air outlet provided on the wall side.

[0005] Since the electric blower having such a blowing action is a source of noise, as a measure for reducing the operation noise of the vacuum cleaner, felt, foamed urethane having open cells, high-density paper, or the like is used. It is common practice to dispose a silencer formed in a cylindrical shape in the exhaust air passage and to allow the wind sent from the electric blower to pass through the silencer to reduce the operating noise. In addition, there is also known an exhaust air path from an electric blower to an exhaust port of a cleaner body having a muffler structure to reduce operating noise.

[0006]

However, since it is impossible to eliminate the imbalance in the rotation of the fan, the electric blower built into the main body of the cleaner with the support structure has its bearing fitting projection centered on the center. As a result, the fan side easily swings greatly, and generates vibration and sound based on the swing.

However, since means for suppressing the vibration has not been conventionally employed, the sound caused by the vibration is emitted around the cleaner body. This vibration sound is, for example, as shown in FIG.
In the frequency analysis diagram (the horizontal axis is a logarithmic scale) (frequency analysis diagram of the operation sound of a conventional vacuum cleaner equipped with an electric blower that rotates a fan having nine blades at 30,000 revolutions per minute),
This is a sound having a relatively large amplitude of 500 Hz, and a sound having a frequency twice as large (1 KHz) is also generated at a relatively large amplitude based on the vibration sound.

Further, in a conventional vacuum cleaner which silences only by using the above-mentioned silencer, in order to realize a more quiet operation, it is necessary to provide a number of silencers such as felts in the exhaust air passage. There is. However, silencers, such as felt, provide airflow resistance, and reduce the momentum of wind sent from the electric blower. Therefore, if many such mufflers are arranged, the airflow resistance will increase accordingly. Therefore, there is a problem that the suction performance of the vacuum cleaner is reduced.

Further, as shown by the sound power level in the frequency analysis diagram of FIG.
The amplitude of the sound at the frequency of KHz and about 9 KHz is particularly large. Among them, the sound of about 9 kHz is out of the frequency range (1 to 6 kHz) of the sound that can be easily heard by the human ear, so it does not matter much, but the sound of about 4.5 kHz (the driving sound level is 58.8 dB) is , Especially those that sound noisy.

[0010] The sound of this frequency is expressed as
rpm / 60 ) × the number of blades of the fan. In addition, a part of the sound of about 4.5 KHz passes through the members around the fan without getting into the exhaust and joins the exhaust outside the electric blower. However, in order to obtain a sufficient silencing effect with a silencing body such as the felt, it is necessary to increase the thickness of the silencing body. However, doing so narrows the air path, which limits its thickness. Therefore, the silencing effect for a sound having a high frequency such as the frequency given by the above equation is small.

[0011] Under the circumstances described above, the conventional vacuum cleaner has a problem that its vibration and operating noise are loud.
Further, in the conventional exhaust air path having a muffler structure, the exhaust air path needs to be formed long, and thus there is a problem that the size of the cleaner body is inevitably large.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electric vacuum cleaner capable of reducing the driving noise and vibration without increasing the size of the main body of the vacuum cleaner and without impairing the suction performance.

[0013]

According to the present invention, a rotating shaft of an electric motor is rotatably supported by two bearings, a fan is mounted on the rotating shaft, and a fan cover for covering the fan is provided. An electric blower whose cover is formed to have a larger diameter than a stator housing wall of a motor case having a wind outlet of the electric motor, and a built-in electric blower formed at a central portion of a bottom wall of the electric motor case, and One side has a built-in bearing fitting projection, and a support rib for supporting the exhaust-side anti-vibration rubber between the projection and the projection, and an intake-side anti-vibration rubber between the protrusion and the peripheral portion of the fan cover. A cleaner main body having a partition wall that supports the electric blower in the thrust direction with the vacuum cleaner interposed therebetween, and an air filter that filters air sucked from a dust suction port of the cleaner main body with a dust collection filter built in the cleaner main body. Is applied to the vacuum cleaner, in order to achieve the object, the portion located between the fan cover and the air outlet of the cleaner main body is provided with a motor support wall that surrounds the stator housing wall from the outside , This support wall
Is harder than rubber in contact with the stator housing wall
A supporting wall main body having a quality portion and supporting the rubber.
The motor support wall separates the fan side and the air outlet side of the electric blower and the electric blower.
An axially intermediate portion of the fan is supported in a radial direction .

In order to further reduce the operation noise, the motor support wall may include a sound deadening material, a first wall portion of the support wall main body overlapping the fan side of the sound deadening material, and the wind of the sound deadening material. A second wall portion of the support wall main body overlapping the outlet side, and a large number of small holes may be provided in one of the first and second wall portions.

[0015]

[Action] Oite to the first aspect, the axial direction of the electric blower
Partition walls at both ends through anti-vibration rubber on the intake and exhaust sides.
Not only supported by rubber and support ribs, but also
Motor support wall supports the axial middle part of the electric blower
In these three places, the electric power inside the vacuum cleaner body
The blower can be reliably supported in a vibration-proof manner. In particular, the motor support wall surrounding the stator housing wall portion of the electric blower from the outside on the upstream side of the air outlet supports the stator housing wall portion in the radial direction, suppresses the vibration of the fan side of the electric blower, and reduces vibration. Reduce the amplitude. The rigid support of this motor support wall
The rubber supported by the wall body prevents the vibration of the electric blower from being transmitted to the cleaner body via the motor support wall. Furthermore, since the motor support wall separates the fan side and the air outlet side of the electric blower, without passing through the inside of the motor,
The sound that propagates to the exhaust side outside the motor case is blocked and attenuated. Moreover, since the operating noise is reduced as described above, a long exhaust air path having a muffler structure is not required to reduce the operating noise, and the motor support wall is provided upstream of the air outlet. Therefore, the support wall does not hinder the flow of the exhausted wind.

In the structure of the second aspect, the motor supporting wall provides effective sound insulation by the three-layer structure of the sound deadening material and the two wall portions. The large number of small holes provided in one wall portion resonate sound having a frequency corresponding to the length of the hole, and attenuate energy of sound having a resonating frequency.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a cross-sectional view showing the structure of the rear part of the vacuum cleaner. In FIG. 1, reference numeral 1 denotes a cleaner main body formed by connecting vertically divided case members to each other, and 2 denotes a main body of the cleaner. The attached rear moving wheel 3 is a carrying handle provided on the upper surface side of the cleaner body 1 and rotatably pivotable about a pivot 4. A dust suction hose or the like is detachably connected to a front part (not shown) of the cleaner body 1 and a dust suction port is detachably connected thereto, and an exhaust port 5 is opened on a rear surface of the cleaner body 1.

At the rear of the cleaner body 1, an electric blower 6 is installed horizontally. As shown in FIG. 1, the electric blower 6 includes an electric motor 7 and a centrifugal fan 9 attached to a front end of a horizontal rotating shaft 8.

The motor 7 has a bottomed cylindrical motor case 1 having a front end opened and a rear end closed as a bottom wall.
0, a substantially rectangular frame-shaped stator 11 is accommodated therein, and a plurality of air passages 12 are formed between the stator 11 and the inner surface of the stator accommodating wall 10a of the motor case 10. Motor case 10
The case end plate 13 traversing the front end opening in the radial direction
The stator 1 is fixed by bearings 14 and 15 fixed to the end plate 13 and the bottom wall of the motor case 10, respectively.
A rotating shaft 8 of a rotor 17 with a commutator 16 arranged inside 1 is rotatably supported. Further, an air outlet 10 b is formed on the bottom wall side of the motor case 10, and a pair of brush devices 18 are attached.
The electric motor 7 is formed with the above configuration. In addition,
The number of revolutions of the electric motor 7 is controlled by a control device (not shown) according to cleaning conditions, and has a capability of rotating the fan 9 30,000 times per minute at its maximum output.

The front end of the rotating shaft 8 penetrates the front bearing 14, and a fan 9 is fixed to the penetrating end.
The number of blades of the fan 9 is, for example, nine. A rectifying plate 19 fixed to the end plate 13 and the motor case 10 is arranged between the fan 9 and the case end plate 13. Furthermore, the motor case 10 has an intake port 20 at the center.
a fan cover 20 having a cover a
Numeral 0 covers and covers the fan 9 and the current plate 19. The fan 9, the current plate 19, and the fan cover 20 have a larger diameter than the stator housing wall 10a.

When the electric blower 6 is operated, the fan 9 is rotated together with the rotor 17, so that air is sucked into the fan 9 from the intake port 20a. Fan cover 20 and current plate 1
9, the air blown through the air passage 12 from the opening between the opening edge of the motor case 10 and the side edge of the case end plate 13 and blown out around the motor case 10 from the air outlet 10a. The action is being carried out.

An annular intake-side anti-vibration rubber 21 is attached to the periphery of the fan cover 20 of the electric blower 6. An exhaust-side anti-vibration rubber 22 is attached outside the bearing fitting protrusion 10c formed at the center of the bottom wall of the motor case 10 and into which the bearing 15 is fitted. The support ribs 23, which are formed integrally with the cleaner body 1 and are vertically continuous,
The bearing fitting projection 10 c is sandwiched between the rubber members 24 via the vibration-proof rubber 22. Further, the fan cover 2 is provided on a support rib 25 and a support wall 26 formed integrally with the cleaner body 1.
Numeral 0 is supported via an anti-vibration rubber 21, and the front surface of the anti-vibration rubber 21 is formed integrally with the cleaner main body 1 and is in close contact with partition walls 27 and 28 that are vertically continuous.
In this way, the electric blower 6 is supported in the radial direction and the thrust direction, respectively, and is built in the cleaner body 1 in a horizontal state.

The space in front of the electric blower 6 installed as described above is a dust collecting chamber 29, in which a bag-shaped or other dust collecting filter (not shown) is stored.
With the blowing action of the electric blower 6, the air sucked from the dust suction port (not shown) of the cleaner main body 1 is filtered. In FIG. 1, reference numeral 30 denotes a filter support.

A pair of ribs is provided on the cleaner body 1 between the fan cover 20 of the electric blower 6 and the air outlet 10b, in other words, at a position facing the stator housing wall 10a of the motor case 10. The mounting portions 31 and 32 which are vertically continuous with each other are provided integrally with each other, and the motor supporting walls 33 which support the stator housing wall portion 10a from outside thereof are mounted on these mounting portions 31 and 32, respectively.

As shown in FIGS. 2 to 4, the motor support wall 33 has a first and second wall portions 34 and 35 which have a semicircular concave portion 36a and are arranged in parallel with each other. A wall main body 36, a sound deadening material 37 built in the main body 36, and a rubber 38 for vibration isolation provided by closing an opening of the support wall main body 36.
And is formed from

The support wall body 36 is harder than the rubber 38.
It is made of a synthetic resin, which is provided in the cleaner main body 1 so as to fit tightly inside the mounting portions 31 and 32. The first wall portion 34 overlaps the silencer 37 on the fan 9 side,
The wall 34 is provided with a number of small holes 39. Second
The wall portion 35 is a blind plate, and the air outlet 10b of the sound deadening material 37 is provided.
On the side. The sound deadening material 37 may be made of a gas-permeable material or a gas-impermeable material.
It is desirable to use a high density, high mass material suitable for attenuating high frequency sounds of Hz. The rubber 38 is provided so as to fit into the opening of the support wall main body 36.

As shown in FIG. 4, the rubbers 38 of the pair of motor support walls 33 are provided so as to be joined to each other, so that their central portions are connected in a ring shape, and this portion is formed on the outer surface of the stator housing wall 10a. Is closely related to Therefore, the electric motor support wall 33 having the above configuration is provided so as to partition the fan 9 side and the air outlet 10b side of the electric blower 6.

As shown in FIG. 1, a muffler cylinder 40 is provided in the cleaner body 1 so as to surround the exhaust side of the motor case 10 from the outside, and its front end is in contact with the second wall 35. And the rear ends are continuous support ribs 23, 2
4 is in contact with the front surface. The silencing tube 40 is made of foamed urethane having open cells. Alternatively, a silencing tube made of felt or high-density paper may be used.

As shown in FIG. 1, a through hole 41 is provided in a portion of the support rib 24 located outside the muffler cylinder 40, whereby the air outlet 10 b extends from the air outlet 10 b of the electric blower 6 to the exhaust port 5. An exhaust air passage 42 is formed.
In the middle of the exhaust air passage 42, a rear silence plate 43 is disposed so as to cross the air passage 42. This silencer 43 is also made of foamed urethane having open cells, but a rear silencer made of felt or high-density paper may be used instead. The exhaust port 5 is formed by a rear end opening of an exhaust port body 44 attached to the rear end of the cleaner body 1.
The muffler plate 43 is supported at the entrance of the housing 4. The exhaust port body 44 has an exhaust air guide 44a.

When the vacuum cleaner having the above configuration is operated,
By the above-described blowing action, the wind passes through the inside of the electric blower 6 and flows out of the air outlet 10b, and is then exhausted to the outside of the cleaner body 1 from the exhaust port 5 through the exhaust passage 42. The sound riding on the exhaust is subjected to a silencing effect by the silencing cylinder 40 in the exhaust air passage 42.

By the above operation, the electric blower 6 tends to swing around the bearing fitting projection 10c. However, the electric blower 6 has both ends in the axial direction protected on the intake side and the exhaust side.
Partition walls 27 and 28, support wall 26 via vibration rubbers 21 and 22
And not only supported by the support ribs 23 to 25
And has a rubber 38 at the tip, and this rubber 38 is
Axial middle by motor support wall 33 supported by body 36
The department is also supported. Such axial ends and intermediate part
In particular, the motor support wall 33
Supports the stator housing wall portion 10a of the motor case 10 in the radial direction, so that the fan cover 20 side of the electric blower 6 is prevented from swinging largely. Therefore, the amplitude of the vibration of the electric blower 6 can be reduced, and the intensity of the vibrating sound accompanying the vibration can be reduced.

The sound generated due to the rotation of the fan 7 (especially, the sound generated at a frequency of 4500 Hz due to the rotation of the electric motor 7 at 30,000 rpm and the number of blades of the fan 9 being nine) 9 wind noise)
The sound transmitted through the fan casing 20 and the fan casing side portion of the motor case 10 propagates to the outside of the motor case 10.

However, the transmitted sound that does not get on the exhaust is blocked by the motor support wall 33 that separates the fan 9 side and the air outlet 10b side of the electric blower 6, so that the transmitted sound is not exhausted by the electric blower 6. , And can be prevented from getting on the exhaust flow. Furthermore, the electric motor support wall 33 can attenuate the transmitted sound by the sound insulation of the first wall portion 34, the sound deadening material 37, and the second wall portion 35, respectively.

In addition, the first wall portion 34 of the motor support wall 33
Has a number of small holes 39 one end of which is closed by a sound deadening material 37.
Is provided, it is possible to attenuate high-frequency sounds among the transmitted sounds. That is, since a sound having a frequency corresponding to the length of the small hole 39 of the transmitted sound resonates in each small hole 39, the sound of the resonance frequency can be attenuated by energy loss consumed for the resonance. Thereby, the level of the entire driving sound can be reduced.

As described above, in combination with the fact that the amplitude of the vibration and the accompanying vibration sound can be reduced, the transmission of the transmitted sound that does not enter the exhaust can be blocked and attenuated.
Since the transmitted sound can be further attenuated by the resonance action at 9, the operation sound of the vacuum cleaner can be reduced.

Since the operation noise is reduced by providing the motor support wall 33 upstream of the air outlet 10b of the motor case 10 as described above, a long exhaust muffler structure is used to reduce the operation noise. There is no need for an air path, and the motor support wall 33 does not obstruct the flow of the exhausted air. Therefore, the operating noise can be reduced without increasing the size of the vacuum cleaner main body 1 and without reducing the suction performance of the vacuum cleaner.

FIG. 5 shows a second embodiment of the present invention.
This embodiment is different from the first embodiment in that a number of small holes 39 for attenuating sound due to resonance are provided in the second wall 35 of the motor support wall 33 and the first wall 34 is a blind plate. Is different from Since the configuration other than this point is the same as that of the first embodiment, including parts not shown in FIG. 5, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted. I do.

[0038] Also Oite to the second embodiment, the electric blower 6
The center part in the axial direction separately from the support at both ends in the axial direction.
By providing the motor support wall 33 as a partition wall for supporting in the radial direction, the intended object of the present invention can be achieved for the same reason as in the first embodiment.
Is provided on the second wall portion 35 on the exhaust side, of the sound on the exhaust, the sound of the frequency corresponding to the length of the small hole 39 can be attenuated by the resonance action. Can also reduce the driving noise.

FIG. 6 shows a third embodiment of the present invention.
In this embodiment, the electric motor supporting wall 33 is formed by a thick supporting wall main body 51 formed integrally with the upper and lower case members of the cleaner main body 1.
And a small hole formed in the support wall main body 51 and having a bottom opening on one side of the fan side thereof. 42 are provided. The small hole 42 may be open on the other side of the air outlet side of the support wall main body 51, or a small hole opened on one side of the fan side of the support wall main body 51, and this small hole is not communicated with the air outlet side. And a number of other small holes opened on the other side. Since the configuration other than the above is the same as that of the first embodiment, including the parts not shown in FIG. 6, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted. .

Also in the third embodiment , the electric blower 6
The center part in the axial direction separately from the support at both ends in the axial direction.
By providing the motor support wall 33 as a partition wall that supports in the dial direction, the intended object of the present invention can be achieved for the same reason as in the first embodiment. Moreover, since the small hole 42 can be formed long, for example, the length of the small hole 42 can be reduced.
When the distance is set to 19.25 mm, it is possible to reduce the amplitude of the sound at the frequency of 4.5 Hz due to the rotation of the fan 9, so that the operating noise can be further reduced. When the resonance frequency of the small hole 42 is fm, the sound speed is C, and an integer constant (1, 2, 3,...) Is N,
The length L of the small hole 42 is L = (2N−1) · C / (4f
m), and the conditions described in the first embodiment (rotational speed 30,000 rotations, power supply frequency 60H)
z, 9 blades of fan 9)
The length of the small hole 42 that resonates the sound of the frequency of 4.5 Hz is 1
It becomes 9.25 mm.

The present invention is not limited to the above embodiments. For example, in the configuration of the first embodiment or the second embodiment, the motor supporting wall 33 may be omitted from the silencer, and in each embodiment, the small hole 39 or the small hole 42 may be used.
May be omitted.

[0042]

As described above in detail, according to the electric vacuum cleaner according to the first aspect, the electric blower whose both ends in the axial direction are supported.
That supports the axial middle part of the
The motive support wall is provided on the upstream side of the air outlet of the electric motor case to suppress the vibration on the fan side of the electric blower , so that the amplitude of the vibration of the cleaner body can be reduced, and the vibration is reduced. Combined with the ability to reduce the vibration noise, the noise propagating to the exhaust side through the outside of the motor case can be blocked by the motor support wall, so that the operating noise can be reduced, and
Since there is no need for a long exhaust air path having a muffler structure or a large number of mufflers such as felt in order to reduce the driving noise, the above-described reduction of the driving noise is accompanied by an increase in the size of the cleaner body, or It can be realized without impairing the suction performance.

According to the second aspect of the present invention, the motor supporting wall formed in three layers by the sound deadening material and the two wall portions effectively shields the sound, and provides a large number of small vacuums. Since the energy of the high-frequency sound is attenuated by the resonance action in the hole, the driving sound can be further reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a rear part of a vacuum cleaner according to a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a configuration around a motor support wall according to the first embodiment.

FIG. 3 is a perspective view showing a support wall main body and rubber of the motor support wall according to the first embodiment.

FIG. 4 is a front view showing a state in which a pair of motor support walls according to the first embodiment are fitted.

FIG. 5 is a sectional view showing a configuration around a motor support wall of the vacuum cleaner according to a second embodiment of the present invention.

FIG. 6 is a sectional view showing a configuration around a motor support wall of a vacuum cleaner according to a third embodiment of the present invention.

FIG. 7 is a frequency analysis diagram of the operation sound of the vacuum cleaner.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vacuum cleaner main body, 5 ... Exhaust port, 6 ... Electric blower, 7 ... Electric motor, 8 ... Rotating shaft, 9 ... Fan, 10 ... Electric motor case,
10a: Stator storage wall, 10b: Wind outlet, 10c ...
Bearing fitting protrusions, 14, 15 ... bearings, 20 ... fan cover, 21 ... intake-side anti-vibration rubber, 22 ... exhaust-side anti-vibration rubber, 2
3, 24 ... support ribs, 27, 28 ... partition walls, 33 ... motor support wall, 34 ... first wall portion (hard portion of motor support wall) ,
35: second wall portion (hard portion of motor support wall) , 37: silencer, 38: rubber, 39: small hole.

Claims (2)

(57) [Claims] 1. A rotating shaft of an electric motor is rotatably supported by two bearings, a fan is mounted on the rotating shaft, and a fan cover for covering the fan is provided. The fan cover covers an air outlet of the electric motor. An electric blower formed with a diameter larger than the stator housing wall of the motor case, and a bearing fitting having the electric blower built therein and formed at the center of the bottom wall of the motor case and having one of the bearings built therein. The electric blower has a support rib for supporting the projection with the exhaust-side anti-vibration rubber interposed between the projection and the projection, and the electric blower is thrust with the intake-side anti-vibration rubber between the protruding portion and the periphery of the fan cover. A vacuum cleaner main body having a partition wall supporting the cleaner in a direction, wherein the air suctioned from a dust suction port of the cleaner main body is filtered by a dust collecting filter built in the cleaner main body. A motor support wall surrounding the stator housing wall from the outside thereof is provided at a portion of the remover body located between the fan cover and the air outlet, and the support wall is provided with the stator
It has rubber in contact with the storage wall and a part harder than this rubber
And a support wall body for supporting the rubber.
The fan side and the air outlet side of the electric blower are partitioned by the motor support wall,
An electric vacuum cleaner characterized in that an interval is supported from a radial direction . Wherein said motor supporting wall, the supporting wall body and silencing member, a first wall portion of the support wall body overlapping the fan side of the sound-deadening material, overlapping the wind outlet of the silencer material
The vacuum cleaner according to claim 1, further comprising a second wall portion, and a large number of small holes provided in one of the first and second wall portions.