JPH01268524A - Vacuum cleaner - Google Patents

Abstract

PURPOSE:To lower the natural vibration frequency of a vacuum cleaner and to shield noise due to a resonance sound by covering an electric blower by a sound shielding cylinder and providing a first and a second openings separately from an exhausting ventilation port for injecting an exhaust air flow. CONSTITUTION:Air sucked in a dust collecting chamber 3 from an inlet port 1a by an electric blower 5 passes a dust case 3a, and is filtered by a filter 3b. Only the air is sucked to the electric blower 5 from the suction port 14 of a fan case 7, exhausted to a sound shielding cylinder 8 from the exhaust port of a motor 6. The most of the air is jetted downward to a sound shielding space 34 from an exhausting ventilation port 8a disposed at the lower part of a back part covering cylinder 10, directed upward and externally exhausted to an external part through an exhaust port 32 from an upper communicating space 35, an exhaust space 33. A residual exhaust air flow reaches to the exhaust port 32 through the exhaust space 33 from first and second openings 15, 16, 18, 19 provided on the sound insulating cylinder 8. By providing the openings for reducing the natural frequency of a resonance sound, the propagation path of an oscillation from the sound shielding cylinder to a cleaner main body is changed to shift a resonance point.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a vacuum cleaner, and more specifically aims to reduce the noise generated by a vacuum cleaner.

(b) Conventional technology Conventional devices of this type include, for example: (1) Japanese Patent Publication No. 57
-29176, (2) Japanese Patent Publication No. 54-5629 and Japanese Utility Model Application Publication No. 49-73265 are known.

The former publication discloses that an electric blower is surrounded by a sound insulating case consisting of a front wall, a partition wall, and a top wall to form a nearly closed sound insulating space; forming a silencing space and an exhaust space in communication with the electric blower by bypassing an exhaust passage for the exhaust flow flowing out from the electric blower;
This reduces the noise generated by the exhaust flow.

In contrast, the latter two publications contain electric farewells.

It is shown that the machine is covered with a sound insulator to insulate the noise generated by the electric blower.

(c) Problems to be solved by the invention However, the former sound insulating case does not bypass the exhaust passage,
The electric blower is simply covered with a sound insulating case, and the latter's sound insulating case is also the same, and it is unclear whether these can actually insulate the noise caused by the exhaust flow originally generated from the electric blower. Power control, which is the mainstream of vacuum cleaners, allows the rotation speed of the electric blower to be approximately 150.
If you avoid reducing it to 0Orpm (250tIZ), tI
There is a risk that the sound emitted from the electric blower, which is more noticeable than the rotation speed band k, may be generated as a resonance sound from the entire vacuum cleaner due to the sound insulating case and the sound insulating space. Moreover, later on,
The side of the fan case, which makes the most noise in electric blowers, is supported on the side of the vacuum cleaner's case via a buffer.
Even if there is a buffer, vibration propagation to the main body case increases, making it difficult to reduce the noise generated from this vibration.

The present invention is capable of reducing the natural frequency of the resonance sound that occurs uniquely when the rotation speed of the electric blower is about 15,000 rpm (250 Hz) and insulating the soundproof cylinder that covers the electric blower.
Another object of the present invention is to provide a vacuum cleaner that can also reduce airflow noise through the inherent function of the soundproof tube.

(d) Means for Solving the Problems This invention includes a dust collection chamber, and further includes an electric blower storage chamber at the rear through a central opening communicating with the dust collection chamber. A vacuum cleaner main body having an exhaust port drilled on the rear surface or rear circumferential side, a lid body that closes the dust collection chamber with an open OT function and has an intake port, a fan,
An electric blower consisting of a fan case containing the fan and a motor, and arranged in the electric blower storage chamber;
A suction opening that communicates with the suction port of the fan case is provided on the central opening side, and an exhaust vent that blows out the exhaust flow generated by the fan is provided on the exhaust port side, and a cushion is provided in the electric blower storage chamber. A soundproof tube is provided to cover the electric blower through a means, and the soundproof tube has a front cover having the suction opening that covers the fan case, and the exhaust vent that covers the motor. The vacuum cleaner is configured to be able to be divided into a rear cover tube, and the rear cover tube has a first opening formed in its rear surface and a second opening formed in its peripheral side.

That is, the present invention provides an electric blower having a fan case and a motor disposed at the rear thereof, which is covered with a soundproof cylinder and housed in a vacuum cleaner body, and an exhaust vent that blows out an exhaust flow by easily covering the rear part of the soundproof cylinder. Separately, a first opening is provided on the rear surface, and a second opening is provided on the peripheral side of the second opening.This allows the soundproof cylinder to prevent resonance sound from being generated as noise from the entire vacuum cleaner, and to reduce its natural frequency. This is to reduce and insulate noise caused by resonance.

(e) Effect With the above configuration, when the electric blower operates, the outer periphery of the fan case vibrates, and the vibration is easily transmitted to the front cover of the soundproof tube. In addition, since first and second openings are provided on the rear and circumferential sides of the rear cover of the soundproof tube, separate from the exhaust vent, the noise caused by the resonance of the soundproof tube can be suppressed in at least two different directions. By changing the propagation path of vibration from the soundproof tube to the vacuum cleaner body, the resonance point between the soundproof tube and the rotational frequency of the electric blower can be shifted. It is possible to reduce the natural frequency of high resonance sound generated by resonating at a specific frequency in the electric blower, and also to reduce noise in all other rotational frequency bands of the electric blower. Furthermore, since the soundproof tube covers the electric blower, it can also insulate the noise generated by the exhaust flow.

(f) Example The present invention will be described in detail below based on embodiments shown in the figures.

Note that this invention is not limited by this.

In Figure 1, the main body of the vacuum cleaner is an upper case L and a lower case 2.
The neck part is provided with an intake port 1a and a dust collection chamber 3, and this dust collection chamber houses a dust case 3a that can be opened and closed with a lid (not shown). An electric blower storage chamber 4 is provided which communicates with the air blower through a filter 3b.

Reference numeral 5 denotes an electric blower, which consists of a fan case (fan cover) containing a motor 6 installed at the rear and a centrifugal fan (not shown) attached to the rotating shaft of the motor at the front.
It consists of 7.

8 is a soundproof tube that covers the electric blower 5, which includes a front cover tube 9 that covers the fan case 7 and a rear cover tube 10 that covers the motor 6.
The locking pawl 11, which has a locking hole 11a protruding from the divided opening surface of the front cover 9, is divided into the rear cover 10.
The locking protrusion I2 provided on the edge of the divided opening is connected by a simple assembly operation. The front bottom surface of the front cover tube 9 has an intake opening that communicates with the intake port I4 of the fan case 7! 3 is drilled in the lower part of the circumferential side of the rear cover tO,
An exhaust vent 8a is provided for blowing out the exhaust flow generated by the fan.

Reference numeral 17 denotes an annular synthetic rubber cushion inner with a rectangular cross-section, which is inserted between the inner surface of the front cover 9 and the outer periphery of the fan case 7 to cover the front cover 9. It is held in fan case 7.

Furthermore, the rear cover 10 has an axial center point 0 on the rear wall.
The opening shape is arcuate in each symmetrical position with respect to the second! In addition to openings 15 and 16, second openings 18 and I9 each having a substantially rectangular opening shape with curls at both ends are bored in symmetrical positions with respect to the axis on both sides of the circumferential wall. There is.

Here, the opening widths of the first openings I5 and 16 are set at the axial center point 0.
The central angle α is preferably 60 to 90°, and in this example, it is set to 90°, and the thickness D is preferably 5 to 20xx, and in this example, it is set to 5. On the other hand, the opening width W of the second openings 18 and 19 is preferably 20 to 50xx, and in this embodiment, if it is set to 20Zm, the thickness d
is 5-20! lI! is preferable, and in this example, it was set to 5u. The rear cover 1O has an inclined surface part 8b that slopes downward toward the rear at the upper part of the circumferential wall, and has a holding opening 20 in the center of the rear wall, while the rear cover 1O has an air vent for exhaust. A sound deadening material 44 made of open-cell polyurethane foam is fixed to the entire inner wall surface except for the opening 8a.

21 is a cushion rear made of synthetic rubber that covers the rear bearing 22 of the motor 6;
At the same time, insert the holding opening 20 in the rear cover.
It has a protrusion 24 that is fitted into and held in the opening 20 and protrudes rearward from the opening 20.

Reference numeral 25 denotes a cross-sectional annular synthetic rubber cushion front fitted into the outer surface of the front cover 9;
5a has a larger diameter than the inner peripheral surface 17a of the cushion inner 17. These cushion inner 17, cushion front 25, and cushion rear 21 constitute a cushion means.

Reference numeral 26 denotes a rear wall of the dust collection chamber 3, and a communication hole 27 for communicating the dust collection chamber 3 and the electric blower storage chamber 4 is bored therein.

Reference numeral 28 denotes a front partition wall constituting the front wall of the electric blower storage chamber 4, in which a support hole 29 facing the communication hole 27 is bored.

30 is a rear partition wall that supports the soundproof cylinder 8 from the rear side;
The base end is fixed and erected in the lower part of the lower case 2 via a pair of body ribs 2a, and has a recess 31 into which the protrusion 24 of the cushion rear 21 is fitted, and the entire rear wall of the rear cover 10 At the same time, the soundproof tube 8 is held on the vacuum cleaner body from the rear side.

Then, the cushion front 25 is inserted and supported into the support hole 29 of the front partition wall 28, and the rear wall 26 of the dust collection chamber 3
Abut the rear cover tube! Cushion rear 2 that sticks out from 0! By fitting and supporting the protrusion 24 into the recess 31, the electric blower 5 is covered with the soundproof cylinder 8, and the front partition wall 2
8 and the rear partition wall 30 to be stored in the storage chamber 4.

Reference numeral 32 designates an exhaust port bored through the exhaust space 33 at the rear of the rear partition wall 30 into the case rear 1b provided at the rear surface of the electric blower storage chamber.

Further, in the electric blower storage chamber 4, a shielding space 34 is provided between the front partition wall 28 and the rear partition wall 30.
A communication space 35 is formed above the soundproof cylinder 8 to communicate the exhaust space 33 and the exhaust space 33 .

Note that 36 is a central opening 36a that supports the filter 3a at its upper end and communicates with the intake opening 13 of the soundproof cylinder 8.
37 is a tool storage section for storing various tools 37a and 37b, 38 is a tool cover, 39 is a fitting claw for the lid body, 40 is a case cover, 4N is a handle;
2 and 43 are a face wheel and a rear wheel, respectively.

The air sucked into the dust collection chamber 3 through the intake port 1a by the operation of the electric blower 5 is then transferred to the dust case 3a.
is filtered by the filter 3b, and only the air is sucked into the electric blower 5 from the suction port 14 of the fan case 7, and is exhausted into the soundproof tube 8 from the exhaust port (not shown) of the motor 6. Most of the flow is from the rear cover 1.
A sound insulation space 34 is provided from the exhaust vent 8a provided at the bottom of the
The gas is ejected downward, further bent upward at the bottom wall, and discharged to the outside via the upper communication space 35 from the exhaust space 33 at the rear of the rear partition wall 30 through the exhaust port 32.

In addition, the remaining exhaust flow is directed to the soundproof tube 8 as shown in Fig. 2.
first and second openings 15.16 and 18.1 provided in
9 to the exhaust port 32 via the exhaust space 33. In other words, the rear cover tube! From the first vents 15 and 16 of 0, noise caused by the exhaust flow and the resonance of the soundproof cylinder 8 is ejected through the sound deadening material 44 toward the shielded space 34 on the rear partition wall 30 side, and further into the partition wall 30. (i) The one bent upward reaches the exhaust space 33 via the upper communication space 35, and (11) the one bent downward is bent upward at the bottom wall and eventually reaches the upper communication space 35. The exhaust space 33 is reached through the second opening! 8 and! 9, the noise caused by the exhaust flow and the resonance sound of the soundproof cylinder 8 is transmitted to the sound deadening material 44, respectively.
The gas is ejected laterally into the shielded space 34 through the air, and then bent upward at the side wall or bottom wall, reaches the exhaust space 33 through the upper communication space 35, and is discharged to the outside.

At this time, the outer periphery of the fan case 7 vibrates the most due to the operation of the electric blower 5, but even if the vibration is transmitted to the soundproof tube 8, the front cover tube 9 of the soundproof tube 8 is prevented by the cushioning means.
The vibration of the vacuum cleaner becomes very small, the vibration transmitted to the vacuum cleaner body is greatly reduced, and the noise generated by this vibration becomes very small.

Further, the soundproof tube 8 covers the electric blower 5, and the soundproof tube 8 covers the electric blower 5.
As described above, the exhaust flow from the shield space 34 reaches the exhaust space 33 via the communication space 35 and is discharged along a long path from the exhaust port 32, so that the noise caused by the exhaust flow is insulated.

On the other hand, the rear cover tube of soundproof tube 8! Openings 15.16 and 18.19 for reducing the natural frequency are provided on the rear and circumferential surfaces of the 0. From here, the noise caused by the resonance of the soundproof rR8 can be discharged in two different directions. It is possible to shift the resonance point between the soundproof tube 8 and the rotational frequency of the electric blower 5 while avoiding changes in the propagation path of vibrations to the main body. It is possible to prevent generation of high resonance sound due to resonance at the frequency (250Hz).

That is, FIG. 3 is a comparative measurement diagram showing the noise measurement results of the conventional example (before countermeasures) and this embodiment (after countermeasures) of the soundproof tube 8 when the electric blower 5 rotates at low speed (curtain notch). In this comparative measurement diagram, the vertical axis is the sound pressure level d
B, horizontal axis represents frequency Hz, right side A, B, C11
Each characteristic measured by an "indicating sound level meter" based on the JIS standard is shown, and in the figure, the solid line X indicates the characteristic value of this embodiment, and the dotted line Y indicates the conventional characteristic value. Conventionally, in the case of low speed rotation (approximately 1500 rpm), due to the influence of the high resonance sound that occurs specifically when the rotation speed of the electric blower 4 is approximately 1500 rpm (250 Hz), the noise at that frequency is lower than that at a frequency of 1. What also stood out was
In this example, it can be seen whether noise during low speed rotation can be reduced by suppressing the generation of high resonance sound.

This is an opening on the rear and side surfaces of the soundproof cylinder 8 that can reduce the natural frequency of the resonance sound in the soundproof cylinder 8! 5゜+6.18
．． 19, the vibration propagation path from the soundproof strip 8 to the vacuum cleaner body is changed, and the resonance point is shifted.

Moreover, as shown in Figure 4, when the electric blower rotates at high speed (
Comparing the conventional example and the present example, it can be seen that noise can be reduced even in the case of a non-contact type. In the figure, the solid line X shows the characteristics of this embodiment, and the dotted line Y shows the conventional characteristic values.

As described above, according to the present embodiment, two If! Since the opening for reducing the natural frequency of A is formed, it is possible to prevent generation of high resonance sound when the electric blower 5 rotates at low speed and high speed. Since the soundproof cylinder 8 was installed, the electric blower storage room 4
A sound insulating space and a sound deadening space can be naturally formed inside the cushion inner 17, reducing the noise caused by the exhaust flow.
, cushion rear 21. The cushion front 25 can also reduce noise caused by vibrations, thereby reducing the noise generated by the vacuum cleaner.

In this example, openings for reducing the natural frequency were provided on the rear and both sides of the soundproof cylinder to prevent high resonance noise during low-speed rotation, but the shape and location of the openings may vary. The present invention is not limited to this, as long as the opening is shaped to allow the noise caused by the resonance of the soundproof cylinder to be discharged in at least two different directions, thereby preventing the high resonance.

Further, in this embodiment, the exhaust port is provided on the rear surface of the electric blower storage chamber, but it may be provided on the peripheral side surface of the rear portion.

(G) Effects of the Invention According to this invention, the first and second vents are provided on the rear surface and the circumferential surface of the rear cover of the soundproof cylinder, respectively, in addition to the exhaust vents.
Because the opening is provided, the noise caused by the resonance of the soundproof tube can be discharged in at least two different directions, and by changing the propagation path of vibration from the soundproof tube to the vacuum cleaner body, resonance between the soundproof tube and the rotational frequency of the electric blower can be avoided. This allows the soundproof cylinder to reduce the natural frequency of the electric blower to reduce its natural frequency and insulate the sound from resonating at a specific frequency when the electric blower rotates at low speed. Noise can also be reduced in all other rotational frequency bands of the blower. Furthermore, since the soundproof tube covers the electric blower, it has the effect of insulating noise generated by the exhaust flow.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a soundproof tube showing an embodiment of the present invention, FIG. 2 is an explanatory diagram of the overall configuration showing an embodiment of the invention, and FIG.
．． FIG. 4 is a comparative measurement diagram showing the noise results of the conventional example and the present example when the electric blower rotates at low speed and at high speed, respectively. G...Top case, 2...Bottom case, 3.
...Dust collection room, 4...Electric blower storage room,
5...Electric blower, 6...Motor, 7
...Fan case, 8...Soundproof tube, 8
a...Exhaust vent, 9...Front cover, IO...Rear cover tube, 13...Intake opening, 14... ...Suction port, 15.16...
...First vent! 7...Cushion inner, 18.19...Second vent, 21...Cushion rear, 25...Cushion front, 26...
・Dust collection chamber rear wall, 27...Communication hole (center opening) 2
8...Front partition wall, 29...Support hole,
30... Rear partition wall, 3!・・・・・・Concavity,
32...exhaust port, 33...exhaust space,
34... Shield space, 35... Communication space.

Claims (1)

[Claims] 1. It has a dust collection chamber, and further has an electric blower storage chamber at the rear through a central opening communicating with the dust collection chamber,
A vacuum cleaner main body having an exhaust port drilled on the rear surface or rear circumferential side of the electric blower storage chamber, a lid body that releasably closes the dust collection chamber and has an intake port, a fan, and a vacuum cleaner body that has an air intake port formed on the rear surface or rear circumferential side of the electric blower storage chamber; It consists of a fan case and a motor, and has an electric blower disposed in the electric blower storage chamber, a suction opening communicating with the suction port of the fan case on the central opening side, and a suction opening communicating with the suction port of the fan case on the exhaust port side. and a soundproof tube that covers the electric blower through a cushion means in the electric blower storage chamber and has an exhaust vent that blows out an exhaust flow, and the soundproof tube has the above-mentioned suction opening that covers the fan case. a front cover tube having a cover and a motor;
The rear cover tube is configured to be divisible into the rear cover tube having the exhaust vent, and the rear cover tube further has a first opening drilled in the rear surface and a second opening drilled in the circumferential side thereof. Vacuum cleaner.