JPS61179121A - Electric cleaner - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a vacuum cleaner, and particularly to a vacuum cleaner with low noise.

[Background of the invention]

Conventional vacuum cleaners have an exhaust chamber adjacent to the electric blower chamber, connect these two chambers with a short flow path, and use sound-absorbing material in the exhaust chamber to muffle the noise generated by the electric blower. The area was not large enough, making it difficult to effectively muffle exhaust noise.

The present invention attempts to muffle noise by providing a long exhaust flow path connecting the electric blower chamber and the exhaust chamber at the bottom of the vacuum cleaner. As described in Japanese Patent No. 49-73263, there is a device in which the exhaust gas is once guided to the bottom and then exhausted from part of the bumpers on both sides of the main body case, aiming at an air cushion effect due to the exhaust flow.

However, in such known examples, no consideration was given to effectively utilizing the bottom exhaust flow path as a muffler. In addition, since the exhaust is discharged to the side, there is a drawback that the exhaust tends to blow onto the user, causing discomfort.

[Purpose of the invention]

A particular object of the present invention is to provide a vacuum cleaner with low noise.

[Summary of the invention]

The configuration of the vacuum cleaner according to the present invention is such that a dust collection chamber, an electric blower chamber containing a built-in electric blower, and an exhaust chamber are arranged in the main body case, and the exhaust air of the electric blower is In a device in which an exhaust flow path is formed so as to lead to the bottom of the main body case and connect to the exhaust chamber, the exhaust air of the electric blower is guided to the bottom of the main body case, and once guided forward, the exhaust flow is directed backward. Instead, an exhaust flow path is formed to lead to an exhaust chamber located at the rear of the main body case.

Further details are as follows.

The present invention introduces the exhaust air from an electric blower to the bottom of the main body case of a vacuum cleaner, and after the exhaust air is once guided forward, the exhaust flow is directed backward and guided into an exhaust chamber provided at the rear of the main body case. In addition, a guide lip is formed at the U-turn portion that changes the direction of the exhaust flow path to divide the flow path along the flow.

This makes it possible to lengthen the exhaust flow path that connects the electric blower room and the exhaust chamber, and by using sound-absorbing material in this exhaust flow path, the sound-absorbing area can be expanded and high sound-damping performance can be ensured. This is what I did.

Further, by forming the guide lip, it is possible to suppress the noise generated by the fluid due to non-uniform flow velocity distribution and flow turbulence.

As a result, the exhaust noise is lowered, making it possible to reduce the noise of the vacuum cleaner.Furthermore, since the exhaust is backwardly exhausted, the user does not feel the discomfort of being blown by the exhaust.

[Embodiments of the invention]

Embodiments of the vacuum cleaner according to the present invention will be described with reference to the drawings.

FIG. 1 is a vertical cross-sectional view of a vacuum cleaner according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the vacuum cleaner seen from below, and Figures 3 and 4 are a conventional vacuum cleaner. A partially opened plan view, a vertical sectional view thereof, and FIGS. 5 and 6 are explanatory diagrams representing model-like flow conditions depending on the presence or absence of guide ribs in the exhaust flow path, and the seventh inner diagram is, Figure 8 is a characteristic diagram showing the velocity distribution of the exhaust flow with and without guide ribs. Figure 8 is a characteristic diagram representing the results of 1/3 octave band frequency analysis of the fluid-generated sound in each case of the same aspect. Figure 9 is , characteristic diagrams showing the results of 1/3 octave band frequency analysis of the exhaust sound in the conventional example and the one according to the present embodiment, Figures 10, 11, 12, and 13 respectively correspond to the other embodiments of the present invention. FIG. 2 is a cross-sectional view of the vacuum cleaner seen from below.

First, in Figures 1 and 2, the main body case 1 of the vacuum cleaner has a dust collection chamber 2 at the front, an electric blower chamber 3 communicating with the dust collection chamber 2 at the rear, and an exhaust chamber 4 at the rear. Furthermore, an exhaust flow path 5'ff is formed at the bottom of the main body case 1 to connect the electric blower chamber 3 and the exhaust chamber 4.

The dust collection chamber 2 has an opening 6 on its upper surface, and a top lid 7 that can be opened and closed is attached above the opening 6.

An inner lid 8 is fixed to the upper lid 7 on the back side of the upper lid 7, that is, at a position facing the opening 6 of the dust collection chamber 2. The rear end of the upper lid 7 is rotatably supported by a shaft (not shown) provided on the central upper surface of the main body case 1, while the front end is supported by a spring 9 at the front end of the main body case 1. The clamp 10 is held in place by a clamp 10 which is biased rearward by the clamp 10.

Inside the dust collection chamber 2, there is a dust collection container 11 which is open at the top and whose other surfaces are covered with a breathable material, and whose top surface faces the inner lid 8 and is detachable. is installed on. An elastic annular packing 12 is fitted on the outer periphery of the upper surface of the dust collecting container 11, and is sandwiched between the dust collecting chamber 2 and the inner lid 8 to maintain airtightness.

The upper lid 7 also has a suction port 13 which has one end opened to the outside and the other end opened to the dust collection container 11 of the dust collection chamber 2 in order to take in dust from a hose (not shown).

Furthermore, the dust collection chamber 2 and the electric blower chamber 3 are separated and communicated by a partition plate 15 having a slit-shaped hole 14tl.

Inside the electric blower room 3, there is an electric blower 17 covered with a cylindrical breathable sound-absorbing cover 16, with a vibration-proof rubber dog 18 at the front end and a small vibration-proof rubber dog 19 at the rear end. It is held horizontally.

On the other hand, the electric blower chamber 3 opens to the exhaust flow path 5 through a communication hole 21 in the bottom surface. This exhaust flow path 5 has an L-shaped rib 20 that divides the flow path in the middle and extends laterally at the rear.
An upstream passage 5a facing forward from the communication hole 21, a downstream passage 5b facing rearward from the front and connected to the exhaust chamber 4 at the rear of the main body case 1, and an upstream passage 5a and a downstream passage 5b. A long exhaust flow path is formed by connecting the U-turn portion 5C.

Further, this U-turn portion 5C is provided with a substantially arc-shaped guide rib 22 that divides the flow path along the flow in order to reduce drifting of the flow due to the U-turn and stall disturbance. A sound absorbing material 23 for sound deadening is attached to the bottom surface of the exhaust flow path 5.

Further, the exhaust chamber 4 communicating with the downstream passage 5b has a sufficiently large internal volume to reduce the flow rate of the inflowing exhaust gas,
An exhaust port 24 opening to the outside is formed in the rear wall, and an exhaust filter 25 for rectifying the exhaust gas is attached.

Next, the operation of the device configured as described above will be explained.

That is, in the above configuration, the dust sucked in from the suction port 13 is collected in the dust collecting container 11, and the air filtered by the filter medium is sucked into the electric blower 17, and the air is sucked into the electric blower room 3.
It enters the exhaust flow path 5 from the communication hole 21 drilled in the bottom of the
The sound is muffled by a sound absorbing material 23 through a long flow path, and is exhausted from the exhaust chamber 4 to the outside.

In general, the amount of sound deadening N in a sound deadening structure using a sound absorbing material is the length tL of the pipe, assuming that the sound deadening structure is a pipe with a uniform cross section.
, the cross-sectional area of the sound-absorbing structure is metal S, the inner circumference length of the cross section is P, and K
As a coefficient determined by the sound absorption coefficient of the sound absorbing material, NR=KXPX
It can be expressed as L÷S. It can be seen that by increasing the length L and decreasing the cross-sectional area S, the amount of silencing can be increased.

Here, for comparison, a conventional example will be explained as follows.

That is, in the conventional vacuum cleaner, as shown in FIGS. 3 and 4, an electric blower chamber 1 is provided at the rear of the main body case 100.
01, the exhaust chamber 102, the cord reel chamber 103, and the exhaust flow path 104 are arranged in a plane, so there is not enough space for noise reduction, and the sound absorbing material 105 attached to the exhaust chamber 102 is not sufficient. Since the sound was being muffled by using the air conditioner, it was not possible to create a large sound-absorbing area, and the sound could not be sufficiently muffled.

In contrast, in the case of the present embodiment shown in FIGS. 1 and 2, there is an upstream passage 5a at the bottom of the main body case 1 that once guides the exhaust gas forward, and a U-turn section that changes the direction of the flow from the front to the rear. 5c, furthermore, since the exhaust flow path 5 having a long flow path and a small cross-sectional area can be formed by the downstream path 5b connected to the exhaust chamber 4, the length and area of the sound absorbing material 23 pasted on the bottom surface can be increased; Since the sound-absorbing cross-sectional area is also smaller, the sound-dampening performance can be significantly improved compared to conventional ones.

However, in the above embodiment, if the U-turn portion 5C of the exhaust flow path 5 does not have the guide rib 22,
As shown in Figure 5, because the flow changes direction rapidly,
It accelerates as it drifts toward the outside O, and stalls due to peeling off at the tip B of the inside L-shaped rib 20, resulting in a significantly slow speed and turbulence.

Note that a in the figure shows the velocity distribution between B and 0.

In this way, the velocity distribution a becomes non-uniform, and the fluid generated noise becomes louder due to the accelerated flow and turbulence.

On the other hand, when the guide rib 22 is provided in the U-turn section 5c, as shown in FIG. As shown in the figure, the velocity distribution C becomes uniform throughout, and the peeling d at B described above becomes small.

As a result, the maximum value of the velocity distribution is low and the turbulence is also small, so the noise generated by the fluid is reduced. −
Figure 8 shows the flow velocity distribution in sections C and D-E.
The results of 1/3 octave band frequency analysis of the fluid-generated sound in each case of the same embodiment are shown.

In the figure, A shows the case where there is no guide rib, and the mouth shows the case where there is the guide rib.

As described above, the guide ribs 22 can reduce the noise generated by the fluid at the U-turn portion 5C.

At the same time, the flow disturbance at the U-turn portion 5C is caused by the guide rib 2.
2, fluid loss is reduced and suction performance is improved.

FIG. 9 also shows the exhaust noise of the conventional vacuum cleaner shown in FIGS. 3 and 4 and the vacuum cleaner according to the present embodiment explained in FIGS. 1 and 2. /3 octave band frequency analysis results.

In the same figure, C is the conventional example, and 2 is the present example, which shows that the present example can significantly reduce exhaust noise.

As explained above, in this embodiment, an upstream passage 5a for once guiding the flow forward is provided at the bottom of the main body case 1 of the vacuum cleaner.
, a long exhaust flow path 5 consisting of a U-turn portion 5C1 that changes the flow direction backward, and a downstream path 5b leading to the exhaust chamber 4 further rearward.
By forming the vacuum cleaner and pasting the sound absorbing material 23 thereon, the sound absorbing area can be increased compared to conventional vacuum cleaners, and the sound deadening performance can be greatly improved.

Furthermore, since the exhaust is from the rear, there is no blowing of exhaust air toward the operator.

Further, a U-turn portion 5 that changes the flow direction of the exhaust flow path 5
Since guide ribs 22 that divide the flow path along the flow are formed in c, the large-scale biased flow is divided into small-scale biased flow, and the flow velocity along the outside is increased and the flow along the inside is separated. Stall and turbulence are alleviated, resulting in a uniform velocity distribution, resulting in lower fluid-generated noise.

In addition to these, the above also reduces fluid loss.
This improves suction performance.

Other embodiments of the present invention will be explained with reference to FIGS. 10 to 13.

In the previous embodiment, the guide ribs 22 were formed at equal intervals, but since the outer portions of the guide ribs 22 are gently curved, the first
In the embodiment shown in Figure 0, the outer spacing is wide.

This greatly reduces fluid loss and facilitates molding when producing plastic products.

In addition, in the previous embodiment, the guide rib 22 is arranged 1 center around B.
Although the guide ribs 22 are formed over a range of 80°, the flow tends to be biased on the downstream side of the U-turn portion 5c, so in the embodiment shown in FIG. 11, guide ribs 22 are partially provided mainly on the downstream side. The legs are also 20a with a wider L-shaped rib.
In addition, the tip facing the U-turn portion 5c is also arcuate to reduce the flow <fI&.

Furthermore, in the embodiment shown in FIG. 12, the centers of the substantially arcuate guide ribs 22 are shifted to reduce the flow toward the downstream channel 5b relative to the upstream channel 5a, thereby reducing flow turbulence. It is something.

Next, in the embodiment shown in FIG. 13, the L-shaped rib 2
0 is provided at an angle of 7 with respect to the center line of the main body case 1, and as it advances from the upstream passage 5a to the downstream passage 5b, the flow passage becomes pinched and becomes an accelerated flow, and in the accelerated flow, separation occurs. This is less likely to occur, and the noise generated by the fluid is also lower.

However, the above-mentioned other embodiments are different from the previous first embodiment.
It goes without saying that in addition to equally producing the effects described in Figures , 2, and 2, each of them also produces its own unique effects as described above.

〔Effect of the invention〕

The present invention can provide a vacuum cleaner with low noise, and can be said to be an invention with excellent practical effects.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a vacuum cleaner according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the vacuum cleaner seen from below, and FIGS. 3 and 4 are a conventional vacuum cleaner. A partially opened plan view, a vertical sectional view thereof, and FIGS. 5 and 6 are explanatory diagrams representing model-like flow conditions depending on the presence or absence of guide ribs in the exhaust flow path, and FIG. FIG. 8 is a characteristic diagram showing the velocity distribution in the exhaust flow path depending on the presence or absence of ribs. FIG. Characteristic diagrams showing the results of 1/3 octave band frequency analysis of the exhaust sounds of the conventional example and the one according to this embodiment, Figure 10゜11.12.13 are as follows:
FIG. 7 is a cross-sectional view from below of a vacuum cleaner according to another embodiment of the present invention. ■... Main body case, 2... Dust collection chamber, 3... Electric blower room, 4... Exhaust chamber, 5... Exhaust flow path, 5a...
・Upstream path, 5b...downstream path, 5C...U-turn part,
17...Electric blower, 20, 20 a---L-shaped rib, 21-...Communication hole, 22 people 2 figures 3 figures and a half r5 figures 1,000 80 circumference skin & [l-4xl hook 9 figure If' 1 comparison [H7] also 10 days 11 figures

Claims (1)

[Claims] 1. A dust collection chamber, an electric blower chamber containing a built-in electric blower, and an exhaust chamber are arranged in the main body case, and the exhaust air of the electric blower is directed to the main body case. In the device in which an exhaust flow path is formed so as to be guided to the bottom and connected to the exhaust chamber, the exhaust from the electric blower is guided to the bottom of the main body case, once guided forward, and then turned backward, A vacuum cleaner characterized in that an exhaust flow path is formed to lead to an exhaust chamber located at the rear of a main body case. 2. A vacuum cleaner according to claim 1, wherein a guide rib is formed in the part of the exhaust flow path where the direction changes from the front to the rear to divide the flow path along the flow.