Electric vacuum cleaner

Abstract

Provided is an electric vacuum cleaner capable of reducing noise. This electric vacuum cleaner comprises: a cylindrical housing having an intake port and an exhaust port; a ventilation passage through which air from the intake port flows to the exhaust port; an electric suction machine provided in the ventilation passage; and a sound reduction part provided in the ventilation passage on the downstream side in the air flow direction from the electric suction machine, the sound reduction part reducing noise, including the driving sound of the electric suction machine, at the sound reduction part. The sound reduction part is provided with a sound reduction pipe having an air-permeable structure on at least a portion of the peripheral surface thereof.

Description

vacuum cleaner

[0001] The present invention relates to an electric vacuum cleaner. This application claims priority to Japanese Patent Application No. 2023-124394 filed in Japan on July 31, 2023, Japanese Patent Application No. 2023-124398 filed in Japan on July 31, 2023, and Japanese Patent Application No. 2023-124402 filed in Japan on July 31, 2023, the contents of which are incorporated herein by reference.

[0002] There is a constant demand for electric vacuum cleaners to further reduce noise generated during operation (mainly noise from the electric suction unit). The electric centrifugal blower described in Patent Document 1 is a blower that pressurizes a fluid by centrifugal force generated by the rotation of an impeller. The discharge fluid, air, is passed axially through a flow path formed on the outside of the motor housing, and then passed through a discharge flow path formed by narrowing the outer frame and discharged outside the machine from a discharge port, thereby reducing noise generated by the motor and impeller. Furthermore, sound-absorbing material is installed inside the electric centrifugal blower to improve noise reduction effect.

[0003] Japanese Patent Application Publication No. 8-93683

[0004] The electric centrifugal blower described in Patent Document 1 reduces noise to a certain extent, but when this electric centrifugal blower is applied to an electric vacuum cleaner, it is desirable to make it even quieter so that, for example, noise generated when the vacuum cleaner is operated at night does not cause a nuisance to nearby residents.

[0005] An object of one aspect of the present invention is to provide a vacuum cleaner made in consideration of the above circumstances.

[0006] One aspect of the present invention provides an electric vacuum cleaner comprising a cylindrical housing having an air intake port and an exhaust port, a ventilation duct that directs air from the air intake port to the exhaust port, an electric suction machine provided in the ventilation duct, and a sound-reducing section that is provided in the ventilation duct downstream of the electric suction machine in the airflow direction and that reduces noise, including the driving sound of the electric suction machine, with the sound-reducing section comprising a sound-reducing tube that has a ventilating structure on at least a portion of its surrounding surface.

[0007] According to the electric vacuum cleaner according to one aspect of the present invention, noise can be reduced.

[0008] 1 is a perspective view showing a first embodiment of the electric vacuum cleaner according to the present invention. FIG. 1 is a longitudinal sectional view of the electric vacuum cleaner of the first embodiment. FIG. 2 is a longitudinal sectional view of the vacuum cleaner body of the electric vacuum cleaner of the first embodiment. FIG. 3 is a longitudinal sectional view of the suction side sound reducing section of the vacuum cleaner body of FIG. 3. FIG. 3 is a longitudinal sectional view of the exhaust side sound reducing section of the vacuum cleaner body of FIG. 3. FIG. 1 is a longitudinal sectional view of the vacuum cleaner body of a first modified example of the first embodiment. FIG. 2 is a longitudinal sectional view of the suction side sound reducing section of the vacuum cleaner body of a second embodiment. FIG. 3 is a longitudinal sectional view of the suction side sound reducing section of the vacuum cleaner body of a third embodiment. FIG. 1 is a cross-sectional view taken along the line II of FIG. 8. FIG. 1 is a longitudinal sectional view of the exhaust side sound reducing section of the vacuum cleaner body of a fourth embodiment. FIG. 2 is a longitudinal sectional view of the exhaust side sound reducing section of the vacuum cleaner body of a fifth embodiment. FIG. 3 is a longitudinal sectional view of a first modified example of the fifth embodiment. FIG. 4 is a longitudinal sectional view of the exhaust side sound reducing section of the vacuum cleaner body of a sixth embodiment. FIG. 4 is a longitudinal sectional view of a first modified example of the sixth embodiment. FIG. 5 is a longitudinal sectional view of a second modified example of the sixth embodiment. FIG. 6 is a longitudinal sectional view of a third modified example of the sixth embodiment. FIG. 7 is a longitudinal sectional view of the exhaust side sound reducing section of the seventh embodiment. FIG. 8 is a longitudinal sectional view of the exhaust side sound reducing section of the eighth embodiment. 20 is a longitudinal sectional view showing an exhaust-side sound reducing portion of a ninth embodiment; FIG. 21 is a longitudinal sectional view showing an exhaust-side sound reducing portion of a tenth embodiment; FIG. 22 is a longitudinal sectional view showing a part of FIG.

[0009] The present invention will be described in more detail below with reference to the accompanying drawings. Note that the following description is illustrative in all respects and should not be construed as limiting the present invention.

[0010] (First Embodiment) Fig. 1 is a perspective view showing a first embodiment of a vacuum cleaner 1 according to the present invention. This vacuum cleaner 1 is a stick-type vacuum cleaner including a vacuum cleaner main body 2 and a suction port body 3 detachably connected to the vacuum cleaner main body 2. The housing 5 of the vacuum cleaner main body 2 has a cylindrical body 6, a cylindrical tapered portion 7 connected to the body 6, a cylindrical first thin housing portion 8 connected to the tapered portion 7, a cylindrical bent portion 9 connected to the first thin housing portion 8, and a cylindrical second thin housing portion 10 connected to the bent portion 9. In this embodiment, the housing 5 is entirely cylindrical, but is not limited to being cylindrical, and may be partially or entirely rectangular, or may be a cylinder with a polygonal cross section.

[0011] The suction port body 3 comprises a suction port body 11 placed on the floor surface F, a joint portion 12 connected to the suction port body 11, and a connecting pipe portion 13 connected to the joint portion 12. By connecting the connecting pipe portion 13 to the suction port body 11 via the joint portion 12, the connecting pipe portion 13 can rotate in the front-rear and left-right directions relative to the suction port body 11. In this description, the direction in which the suction port body 3 moves forward will be referred to as the front, the opposite side will be referred to as the rear, and the right side as you face the front will be referred to as the right side, and the opposite side will be referred to as the left side.

[0012] 2 is a vertical cross-sectional view of the electric vacuum cleaner 1 of the first embodiment. In the housing 5 of the vacuum cleaner main body 2, of the body 6, the first thin housing part 8, and the second thin housing part 10, the body 6 has the largest inner and outer diameters, the first thin housing part 8 has the next largest inner and outer diameters, and the second thin housing part 10 has the smallest inner and outer diameters. Inside the housing 5, a partition wall 21 is provided at the boundary between the first thin housing part 8 and the second thin housing part 10, separating the internal space of the first thin housing part 8 from the internal space of the second thin housing part 10, and the internal space of the first thin housing part 8 and the internal space of the second thin housing part 10 do not communicate with each other.

[0013] 2 shows the state of the vacuum cleaner 1 when cleaning a floor F, in which, when the user holds the second thin housing portion 10, the suction mouth body 3 of the vacuum cleaner 1 is positioned at the frontmost position, the second thin housing portion 10 is positioned at the rearmost position, and the vacuum cleaner body 2 is tilted backward from the bottom end 14 to the top end 15. The second thin housing portion 10 is formed thinner than the first thin housing portion 8 to make it easier for the user to grip, and functions as a handle, and is tilted further toward the floor F relative to the first thin housing portion 8 to make it easier for the user to grip. In the following description, the bottom end 14 of the vacuum cleaner body 2 shown in FIG. 2 may be referred to as one end 14, and the top end 15 may be referred to as the other end 15.

[0014] 3 is a longitudinal cross-sectional view showing the vacuum cleaner body 2 of the electric vacuum cleaner 1 of the first embodiment. The housing 5 of the vacuum cleaner body 2 has an air intake 31 on an end surface of one end 14 of the body 6 and an air exhaust 32 around the periphery of the body 6. Inside the housing 5, there are provided an air passage 33 through which air from the air intake 31 flows to the air exhaust 32, an electric suction device 34 provided in the air passage 33, a dust collection unit 35 provided in the air passage 33 upstream of the electric suction device 34 in the airflow direction, an air intake-side sound-reducing unit 36 ​​provided in the air passage 33 between the dust collection unit 35 and the electric suction device 34 and constituting a part of the air passage 33, and an air exhaust-side sound-reducing unit 37 provided in the air passage 33 between the electric suction device 34 and the air exhaust 32 and constituting a part of the air passage 33. Furthermore, in this embodiment, the suction port body 3 is provided with an air intake-side sound-reducing unit 22 (see FIG. 2 ).

[0015] 3, the second thin housing 10 is provided at a position away from the electric suction device 34 and has a hollow interior, which may house a battery as a power source for driving the electric suction device 34 or an electric cord with a plug that can be connected to a commercial power source. The connection portion 13a (see FIG. 2) of the connection pipe portion 13 of the suction port body 3 can be inserted into and connected to the air intake 31 of the housing 5 of the vacuum cleaner main body 2.

[0016] In the vacuum cleaner main body 2, a dust collection unit 35, an intake-side sound reduction unit 36, and an electric suction device 34 are provided within the trunk 6, in this order from the intake port 31 side. The dust collection unit 35 has an inlet 35a at one end through which dust-containing air flows in from the intake port 31, and an outlet 35b at the other end through which dust-free air is discharged to the intake-side sound reduction unit 36. A dust collection bag or a dust collector is housed in the internal space of the dust collection unit 35. In the case of a dust collection bag, a so-called paper bag is used, which collects dust inside a breathable pack body. In the case of a dust collector, if the dust collection device includes a container body and a filter, it is possible to configure the dust captured by the filter to be stored in the container body, and the dust-free air to be exhausted from the exhaust port of the dust collection device. Alternatively, a cyclone-type dust collector may be provided with a cyclone section including a centrifugal separator (inner cylinder) and a container body. The cyclone section separates dust, stores the separated dust in the container body, and exhausts the dust-free air from the cyclone section's exhaust port. A retractable lid (not shown) forming part of the housing 5 is provided near the dust collector 35. The lid can be opened to remove the dust collection pack or dust collector (dust collection container) from the dust collector 35 and discard the dust. The lid has a double structure in which a portion of the outer wall (housing 5) and a portion of the wall forming the dust collector 35 are integrated. The dust collection pack is removed by opening the lid. The double-structure lid also reduces noise during operation. To more effectively reduce wind noise (intake), a filter-type dust collector or dust collection pack is preferably used rather than a cyclone-type dust collector. This is because in cyclone-type dust collectors, the wind speed increases in the cyclone section, increasing wind noise. Filter-type dust collectors and dust collection packs do not have a cyclone section, so they can reduce wind noise (intake) more than cyclone-type dust collectors.

[0017] Figure 4 is a vertical cross-sectional view showing the suction-side sound-reducing section 36 of the vacuum cleaner body of Figure 3. The suction-side sound-reducing section 36 includes a sound-reducing pipe 41 having an opening at one end 36a connected to the discharge port 35b of the dust collecting section 35 and an opening at the other end 36b connected to the suction port 34a of the electric suction device 34. The suction-side sound-reducing section 36 is configured to reduce noise, including the ventilation noise of air flowing from the dust collecting section 35 to the suction-side sound-reducing section 36 and the driving noise of the electric suction device 34 flowing from the electric suction device 34 to the suction-side sound-reducing section 36; the detailed configuration and sound-reducing effect of the suction-side sound-reducing section 36 will be described in detail below.

[0018] Cylindrical sound-reducing covers 38, 39 are provided around the sound-reducing pipe 41 and the electric suction device 34. The intake-side sound-reducing section 36 includes the sound-reducing cover 38 around the sound-reducing pipe 41. A gap is provided between the housing 5 and the sound-reducing covers 38, 39, and this gap forms part of the ventilation passage 33. The housing 5 is provided with a large number of through-hole-shaped exhaust ports 32 in a section that extends from near the discharge port 35b of the dust collecting section 35 to the electric suction device 34 and that becomes the underside during cleaning.

[0019] 3 , the exhaust-side sound-reducing section 37 includes a sound-reducing tube 51. The sound-reducing tube 51 has a first end opening 37a connected to the sound-reducing cover 39 and a second end opening 37b located near the partition wall 21 inside the first thin housing 8 (see FIG. 5 ). The second end opening 37b of the sound-reducing tube 51 opens toward the partition wall 21 at the other end of the first thin housing 8. The exhaust-side sound-reducing section 37 is configured to reduce noise including ventilation noise of air flowing downstream in the airflow direction from the electric suction machine 34 and driving noise of the electric suction machine 34 flowing downstream in the airflow direction from the electric suction machine 34; the detailed configuration and sound-reducing action of the exhaust-side sound-reducing section 37 will be described in detail below. In the vacuum cleaner main body 2, the dust collection section 35, the intake side sound reduction section 36, the electric suction machine 34 and the exhaust side sound reduction section 37, which are arranged in order from upstream to downstream in the airflow direction of the ventilation passage 33, are aligned on the same central axis 40.

[0020] 3, the ventilation path 33 includes a first exhaust path 33A extending from the electric suction machine 34 to the inside of the first thin housing 8 and a second exhaust path 33B that turns back at the partition wall 21 inside the first thin housing 8 and extends to the exhaust port 32. The first exhaust path 33A is an exhaust path formed by the sound attenuation tube 51 of the exhaust-side sound attenuation section 37, and the second exhaust path 33B is an exhaust path formed by the outer periphery of the sound attenuation tube 51 and the first thin housing 8. Furthermore, the ventilation path 33 includes a first expansion section 33C at the turning point between the first exhaust path 33A and the second exhaust path 33B, and a second expansion section 33D midway along the second exhaust path 33B. Therefore, when the electric suction device 34 is driven, the air in the ventilation path 33 passes from the intake port 31 through the dust collection section 35, the intake-side sound reduction section 36, the electric suction device 34, and the first exhaust path 33A, enters the first expansion section 33C, turns back, flows into the second exhaust path 33B, passes through the second expansion section 33D midway along the second exhaust path 33B, and is discharged to the outside through the exhaust port 32. Note that a sound-absorbing material may be attached to the partition wall 21. The intake air passes through multiple parts that have a sound-reducing effect before being exhausted from the exhaust port 32, such as sound reduction by the suction port body-side sound-reducing section 22 described below, sound reduction by the intake-side sound-reducing section 36, sound reduction by the exhaust-side sound-reducing section 37, sound reduction by the second exhaust path 33B that forms a long exhaust path by having a folded-back portion between the first exhaust path 33A and the second exhaust path 33B between the exhaust-side sound-reducing section 37 and the exhaust port 32, and sound reduction by the first expansion section 33C provided at the folded-back portion between the first exhaust path 33A and the second exhaust path 33B and the second expansion section 33D provided midway along the second exhaust path 33B. Therefore, compared to a case in which multiple parts with a sound-reducing effect, including sound-reducing sections, are not provided, the sound reduction effect is improved, and an electric vacuum cleaner with quieter operation can be realized. In this case, since the dust collection section 35, the intake side sound reduction section 36, the electric suction machine 34 and the exhaust side sound reduction section 37 are aligned on the same central axis 40 within the housing 5, exhaust loss can be kept low and suction performance can be maintained.

[0021] <Intake-Side Sound Attenuator> Returning to FIG. 4 , the intake-side sound attenuator 36 includes a ventilated sound attenuator tube 41. The sound attenuator tube 41 includes a straight tube section 41a having a constant inner and outer diameter and extending straight, and a tapered section 41b whose opening widens toward the upstream side (one end) in the airflow direction. Hereinafter, the tapered section 41b of the sound attenuator tube 41 of the intake-side sound attenuator 36 may be referred to as the first tapered section 41b. The first tapered section 41b is located on the upstream side (one end) of the sound attenuator tube 41 in the airflow direction, and the one-end opening 36a, which is the largest opening of the first tapered section 41b, is connected to the exhaust port 35b of the dust collector 35. The other end (the end on the other end side), which is the smallest opening of the first tapered section 41b, is connected to one end (the end on the one end side) of the straight tube section 41a. The straight pipe section 41a may have a shape that does not have a tapered section 41b on one end side. If the straight pipe section 41a does not have a tapered section, the dust collection section 35 can be expanded to include the tapered section, thereby increasing the capacity of the dust collection section 35. Alternatively, the noise reduction effect can be improved by extending the straight pipe section 41a to include the tapered section and providing a through-hole 42 (described later) at the extended section. Furthermore, a curved pipe, a pipe bent like a crank, or the like may be used instead of the straight pipe section 41a of the sound-reducing pipe 41.

[0022] The sound attenuation tube 41 has a ventilation structure on at least a portion of its peripheral surface. In this embodiment, the ventilation structure of the sound attenuation tube 41 is a plurality of through-holes 42 that penetrate the inner and outer surfaces of the straight tube portion 41a. The plurality of through-holes 42 are provided around the entire circumference of the straight tube portion 41a, extending from one end of the straight tube portion 41a to the vicinity of the other end opening 36b. The plurality of through-holes 42 allow air inside the straight tube portion 41a to ventilate into an expansion chamber 43, which is the internal space between the straight tube portion 41a and the sound attenuation cover 38. The expansion chamber 43 is an annular space centered on the central axis 40 of the vacuum cleaner body 2. In this embodiment, the through-holes 42 are circular, but the shape of the through-holes 42 is not particularly limited and may be elliptical, oblong, polygonal (including a lattice shape) such as a triangle or a rectangle, or an irregular shape. Furthermore, in the present embodiment, the through holes 42 penetrate the straight pipe portion 41a in a direction perpendicular to the central axis 40, but the through holes 42 may penetrate the straight pipe portion 41a in a direction oblique to the central axis 40. Furthermore, the range in which the multiple through holes 42 are provided may not be the entire longitudinal circumference of the straight pipe portion 41a, but may be a part of the circumference, or may be a range extending from the vicinity of one end of the straight pipe portion 41a to the vicinity of the other end opening 36b, or a range extending from the end of one end of the straight pipe portion 41a to the other end opening 36b. Alternatively, the through holes 42 may not be provided in the middle of the straight pipe portion 41a, but may be provided in a predetermined range toward the end of one end and a predetermined range toward the other end opening 36b.

[0023] 4, an annular sealing member (not shown) is provided around the vicinity of the suction port 34a of the electric suction machine 34, and the other end opening 36b of the sound attenuation tube 41 is in close contact with this sealing member. The inner diameter of the other end opening 36b of the sound attenuation tube 41 is slightly larger than the inner diameter of the suction port 34a of the electric suction machine 34, and the other end opening 36b completely surrounds the suction port 34a.

[0024] In this embodiment, a connecting tubular portion 44 is provided on the other end side of the sound attenuation tube 41. The connecting tubular portion 44 has an inner diameter and an outer diameter larger than the inner diameter and outer diameter of the other-end opening 36b of the sound attenuation tube 41, and the other-end opening 44a of the connecting tubular portion 44 is connected to the one-end opening 39a of the sound attenuation cover 39. Furthermore, a step portion 44b is provided on the connecting tubular portion 44 on the one-end side of the other-end opening 44a, and the other-end opening 38a of the sound attenuation cover 38 is fitted into and connected to the outer peripheral surface of the step portion 44b. The one-end opening 38b of the sound attenuation cover 38 abuts against the outer surface of the first tapered portion 41b of the sound attenuation tube 41 with almost no gap between them.

[0025] According to this embodiment, during cleaning, the intake-side sound-reducing unit 36 ​​can suppress noise leakage to the outside of the housing 5, including airflow noise generated when air flows in and out of the dust collecting unit 35 and drive noise generated by the electric suction device 34, in the following manner: Noise generated on the dust collecting unit 35 side and the electric suction device 34 side is transmitted inside the sound-reducing tube 41. The noise (sound waves) is introduced into the expansion chamber 43 through the multiple through-holes 42 of the sound-reducing tube 41, and a portion of the noise is reduced by sound wave interference within the expansion chamber 43. This reduces the level of noise leaking to the outside of the housing 5. Furthermore, a sound-reducing cover 38 is provided on the outside of the other end of the straight tube portion 41a and the first tapered portion 41b of the sound-reducing tube 41 as an inner cylindrical wall of the inner space (expansion chamber 43), and the housing 5 is provided on the outside of the sound-reducing cover 38 as an outer cylindrical wall of the outer space (part of the second exhaust passage 33B). In this way, the intake-side sound-reducing section 36 has a configuration in which, from the inside of the sound-reducing pipe 41 to the outside, a wall (sound-reducing pipe 41), a space (expansion chamber 43), a wall (sound-reducing cover 38), a space (part of the second exhaust path 33B), and a wall (housing 5) are arranged, so this structure also contributes to noise reduction. Furthermore, the sound-reducing cover 39 around the electric suction machine 34 also contributes to noise reduction.

[0026] <Exhaust-Side Sound Attenuating Section> Figure 5 is a longitudinal cross-sectional view showing the exhaust-side sound attenuating section 37 of the vacuum cleaner body 2 of Figure 3. As shown in Figure 5, the first exhaust passage 33A has a ventilated sound attenuating pipe 51. The sound attenuating pipe 51 has a straight pipe section 51a and a tapered section 51b whose opening widens toward the upstream side (one end) in the airflow direction. Hereinafter, the tapered section 51b of the sound attenuating pipe 51 of the exhaust-side sound attenuating section 37 may be referred to as the second tapered section 51b. The second tapered section 51b is provided on the upstream side (one end) of the sound attenuating pipe 51 in the airflow direction, and the one-end opening 37a, which is the largest opening of the second tapered section 51b, is connected to the other-end opening of the sound attenuating cover 39. The other end, which is the smallest opening of the second tapered section 51b, is connected to one end of the straight pipe section 51a. High-frequency sound from the electric suction device 34 is attenuated while being reflected off the tapered inner surface of the second tapered portion 51b, whose cross-sectional area decreases toward the downstream side in the air flow direction. The length from one end to the other of the second tapered portion 51b is longer than the longitudinal length of the electric suction device 34. By lengthening the length of the second tapered portion in this way, the taper angle of the second tapered portion 51b can also be made gentler, thereby improving the attenuation effect of high-frequency sound.

[0027] The sound attenuation tube 51 has a ventilation structure on at least a portion of its peripheral surface. In this embodiment, the ventilation structure of the sound attenuation tube 51 is a plurality of through holes 53 that penetrate the inner and outer surfaces of the straight pipe portion 51a. The range in which the plurality of through holes 53 are provided is the entire circumference of the straight pipe portion 51a, extending from near one end of the straight pipe portion 51a to near the middle portion. A sound attenuation cover 56 that covers the plurality of through holes 53 is provided in the range in which the plurality of through holes 53 are provided in the straight pipe portion 51a. The plurality of through holes 53 allow air inside the straight pipe portion 51a to ventilate into an expansion chamber 57, which is the internal space between the straight pipe portion 51a and the sound attenuation cover 56. The expansion chamber 57 is an annular space centered on the central axis 40 of the vacuum cleaner body 2. In the present embodiment, the through holes 53 are circular; however, the shape of the through holes 53 is not particularly limited and may be elliptical, oval, polygonal (including lattice-shaped) such as triangular or rectangular, or irregular. The second exhaust passage 33B is an annular space surrounding the sound-reducing tube 51. The range in which the multiple through holes 53 are provided may be a range extending over the entire longitudinal circumference of the straight pipe section 51a, a range extending from near one end of the straight pipe section 51a to near the other end opening 36b, or a range extending from the end of the straight pipe section 51a to the other end opening 37b. Alternatively, the through holes 53 may not be provided in the middle of the straight pipe section 51a, but may be provided in a predetermined range near the one end and a predetermined range near the other end opening 37b. In the present embodiment, the through holes 53 penetrate the straight pipe section 51a perpendicular to the central axis 40; however, the through holes 53 may penetrate the straight pipe section 51a obliquely relative to the central axis 40.

[0028] During cleaning, noise generated by the electric suction device 34 is transmitted inside the sound-reducing tube 51. The noise (sound waves) is introduced into the expansion chamber 57 through the multiple through-holes 53 of the sound-reducing tube 51, where a portion of the noise is attenuated by sound wave interference within the expansion chamber 57. This reduces the level of noise leaking outside the housing 5. A sound-absorbing material may be provided to cover at least a portion of the outer surface or inner surface of the sound-reducing tube 51, or a sound-absorbing material may be provided to cover at least a portion of the outer surface or inner surface of the sound-reducing cover 39. The electric suction device 34 is preferably attached to the sound-reducing cover 39 or the tapered portion 51b of the sound-reducing tube 51 via an elastic member such as rubber. This reduces the transmission of vibrations from the electric suction device 34 to the sound-reducing cover 39 or the tapered portion 51b. The sound-reducing cover 39 or the sound-reducing tube 51 is preferably attached to the inner surface of the housing 5 via an elastic member such as rubber. This reduces the transmission of vibrations from the electric suction device 34 to the housing 5. Furthermore, rubber (e.g., butyl rubber) may be attached to the electric suction machine 34, the sound-reducing cover 39, the sound-reducing tube 51, etc. This reduces transmission of vibrations from the electric suction machine 34 to the housing 5. The second expansion section 33D around the exhaust-side sound-reducing section 37 is formed by making the angle that the tapered section 7 of the housing 5 forms with respect to the central axis 40 gentler than the angle that the tapered section 51b of the sound-reducing tube 51 of the exhaust-side sound-reducing section 37 forms with respect to the central axis 40, and by positioning the end of the tapered section 7 on the first thin housing section 8 side closer to the second thin housing section 10 (the other end side) than the end of the tapered section 51b on the straight tube section 51a side (see FIG. 5 ).

[0029] <Regarding the Suction Port Body-Side Sound Attenuating Section> As shown in FIG. 2 , the suction port body-side sound attenuating section 22 is provided inside the connecting pipe 13 of the suction port body 3. The suction port body-side sound attenuating section 22 has a sound attenuating tube 22b with multiple through-holes 22a formed around its entire circumference. An expansion chamber 23 is provided between the housing of the connecting pipe 13 and the sound attenuating tube 22b, surrounding the sound attenuating tube 22b. During cleaning, noise generated on the vacuum cleaner body 2 side is transmitted inside the suction port body-side sound attenuating section 22. The sound waves are introduced into the expansion chamber 23 through the through-holes 22a, and a portion of the noise is attenuated by sound wave interference within the expansion chamber 23. This reduces the level of noise leaking to the outside. The suction port body 3 may have multiple through-holes in the upper wall of a rotary brush housing section that houses the rotary brush 24, and an expansion chamber may be provided above the upper wall of the rotary brush housing section, thereby providing a separate suction port body-side sound attenuating section. This separate suction port body side sound reduction section can reduce noise including the driving noise of the rotary brush 24 and airflow noise.

[0030] As described above, in the first embodiment (see FIG. 2 ), the rotary brush 24, dust collection unit 35, and electric suction unit 34, which are noise generating components, are concentrated upstream of the airflow direction of the vacuum cleaner 1, with no noise generating sources located downstream. Furthermore, the second thin housing 10, which functions as a handle and is thinner than the first thin housing 8 to facilitate a user's grip, is located at the opposite end farthest from the suction port body 3. This structure positions noise generating sources farther from the user using the vacuum cleaner 1, while providing a sound-reducing structure closer to the user, reducing the transmission of noise to the user. In this embodiment, the vacuum cleaner body 2 is constructed using cylindrical components, such as the dust collection unit 35, the straight pipe portion 41a of the sound-reducing pipe 41, the sound-reducing covers 38 and 39, and the straight pipe portion 51a of the sound-reducing pipe 51. However, the components are not limited to being cylindrical and may be partially or entirely rectangular or have a polygonal cross section.

[0031] (Variation 1 of the First Embodiment) FIG. 6 is a longitudinal cross-sectional view showing a vacuum cleaner main body according to Variation 1 of the first embodiment. In FIG. 6, elements similar to those in FIG. 3 are denoted by the same reference numerals. In the vacuum cleaner main body 2X according to Variation 1, the positions of the multiple exhaust ports 32 are closer to one end of the housing 5 than the electric suction device 34. That is, while the exhaust ports 32 are provided in a portion overlapping with the electric suction device 34 in the first embodiment (see FIG. 3), the exhaust ports 32 are not provided in a portion overlapping with the electric suction device 34 in Variation 1. For example, the exhaust ports 32 may be provided in a portion that is on the underside during cleaning, extending from near the discharge port 35b of the dust collection unit 35 to in front of the electric suction device 34. This eliminates the exhaust ports 32 facing and close to the sound-reducing cover 39 that covers the electric suction device 34, thereby reducing noise leakage to the outside compared to when there are exhaust ports 32 facing and close to the sound-reducing cover 39 (see FIG. 3).

[0032] (Second Modification of First Embodiment) In the intake-side sound-attenuating section 36 of the first embodiment shown in FIG. 4 , a plurality of through holes 42 are provided on the peripheral surface of the sound-attenuation tube 41 as a ventilated structure. However, the ventilated structure provided on the peripheral surface of the sound-attenuation tube 41 is not limited to a plurality of through holes 42. For example, a ventilated porous sound-absorbing material may be provided on the peripheral surface (inner surface) of the sound-attenuation tube 41 that does not have through holes. In this case, the sound-attenuation cover 38 may be omitted from the sound-attenuation tube 41. Alternatively, a portion of the sound-attenuation tube 41 that does not have through holes may be made of a ventilated porous sound-absorbing material. In this case, noise (sound waves) pass through the sound-absorbing material and enter the expansion chamber 43, where they are reduced.

[0033] Second Embodiment Figure 7 is a vertical cross-sectional view showing the suction-side sound-reducing section 61 of the vacuum cleaner body 2 of a second embodiment. In Figure 7, elements that are the same as those in Figure 4 are given the same reference numerals. The second embodiment differs from the first embodiment only in the configuration of the suction-side sound-reducing section 61; the other configurations of the second embodiment are the same as those of the first embodiment. Below, the differences between the second embodiment and the first embodiment will be mainly described.

[0034] 7, in the second embodiment, the intake-side sound-reducing section 61 includes a sound-reducing pipe 41 similar to that of the first embodiment, which has a straight pipe portion 41a and a tapered portion 41b, and a sound-absorbing material 62 that covers the entire outer surface of the straight pipe portion 41a of the sound-reducing pipe 41. The sound-absorbing material 62 may be, for example, a thin sheet of urethane foam. By providing the sound-absorbing material 62, sound waves attempting to enter the expansion chamber 43 are absorbed by the sound-absorbing material 62, further improving sound insulation performance (noise reduction performance).

[0035] 7 illustrates an example in which a thin sheet-like sound-absorbing material 62 is wrapped around the outer surface of the sound attenuation tube 41, but the sound-absorbing material 62 may be large enough to cover almost the entire interior of the expansion chamber 43 (large enough to fill almost the entire interior of the expansion chamber 43). Also, the sound-absorbing material 62 may cover only a portion of the outer surface of the sound attenuation tube 41, or may cover at least a portion of the inner surface of the sound attenuation tube 41, or may cover at least a portion of both the outer and inner surfaces of the sound attenuation tube 41.

[0036] Referring to FIG. 5 , the exhaust-side sound-reducing section of the second embodiment will be described. The exhaust-side sound-reducing section includes a sound-reducing pipe 51 similar to that of the first embodiment, having a straight pipe portion 51a and a tapered portion 51b, and a thin sheet-like sound-absorbing material (not shown) covering the entire outer surface of the straight pipe portion 51a of the sound-reducing pipe 51. For example, urethane foam can be used as the sound-absorbing material. By providing the sound-absorbing material, sound waves attempting to enter the expansion chamber 57 are absorbed by the sound-absorbing material, thereby further improving sound insulation performance. While the example shows a case in which the thin sheet-like sound-absorbing material is wrapped around the outer surface of the sound-reducing pipe 51, the sound-absorbing material may be large enough to cover almost the entire interior of the expansion chamber 57 (i.e., large enough to fill almost the entire interior of the expansion chamber). Furthermore, the sound-absorbing material may cover only a portion of the outer surface of the sound-reducing pipe 51, or may cover at least a portion of the inner surface of the sound-reducing pipe 51, or may cover at least a portion of both the outer and inner surfaces of the sound-reducing pipe 51.

[0037] Explaining the second embodiment further with reference to FIG. 5 , a sound-absorbing material (e.g., urethane foam) (not shown) may be installed in the second exhaust path 33B. More specifically, the annular space around the sound-reducing pipe 51, which is the second exhaust path 33B, may be filled with sound-absorbing material. The sound-absorbing material used should be breathable and allow exhaust air to pass through. While this may make exhaust somewhat more difficult, sound waves are absorbed by the sound-absorbing material, improving the sound-reducing effect. The first expansion section 33C, located at the turnback between the first exhaust path 33A and the second exhaust path 33B, and the second expansion section 33D, located midway along the second exhaust path 33B, may also be filled with similar sound-absorbing material.

[0038] (Third embodiment) Figure 8 is a vertical cross-sectional view showing the intake-side sound-reducing section 71 of the vacuum cleaner body 2 of the third embodiment. Figure 9 is a cross-sectional view taken along the line I-I in Figure 8. In Figure 8, elements that are the same as those in Figure 4 are given the same reference numerals. The only difference between the third embodiment and the first embodiment is the configuration of the intake-side sound-reducing section 71; the other configurations of the third embodiment are the same as those of the first embodiment. Below, the differences between the third embodiment and the first embodiment will be mainly described.

[0039] 8 and 9 , in the third embodiment, the intake-side sound-reducing section 71 is provided between the tapers of the first tapered section 41b and further includes a circular reflector 72 that reflects drive noise from the electric suction device 34. The reflector 72 has a plurality of legs 73 that are fixed to the inner surface of the first tapered section 41b. The reflector 72 has a planar area larger than the area of ​​the smallest opening 74 of the first tapered section 41b and is positioned so as to overlap the smallest opening 74 of the first tapered section 41b when viewed in the direction of the rotation axis of the electric suction device 34 (the direction of the central axis 40). The reflector 72 is made of resin, metal, a composite material thereof, or the like.

[0040] A gap is provided between the reflecting plate 72 and the inner surface of the first tapered portion 41b, allowing air and noise from the dust collecting unit 35 to pass through. By providing the reflecting plate 72 in the intake-side sound-reducing unit 71 of the third embodiment, when sound waves (driving noise) from the electric suction machine 34 pass through the straight pipe portion 41a of the sound-reducing pipe 41, the sound waves are reflected by the reflecting plate 72, thereby reducing the likelihood of sound waves emitted from the opening 74 heading directly toward the dust collecting unit 35. The reflecting plate may also be positioned so that sound waves reflected by the reflecting plate 72 and returning to the straight pipe portion 41a and sound waves heading from the electric suction machine 34 toward the straight pipe portion 41a collide with and cancel each other out. Therefore, according to the intake-side sound-reducing unit 71 of the third embodiment, in addition to reducing noise (sound waves) that pass through the multiple through holes 42 of the straight pipe portion 41a of the sound-reducing pipe 41 in the expansion chamber 43, as in the first embodiment, the noise-reducing effect of the reflecting plate 72 can be obtained. If the sound-reducing tube 41 does not have a tapered section 41b whose opening widens toward the upstream side (one end) in the airflow direction, the opening 74 can be connected to a hole in the other end wall of the dust collecting section 35 that faces the upstream opening 74 of the straight tube section 41a, a lattice plate can be provided a short distance from the other end wall within the dust collecting section 35, and a reflector 72 can be placed on the lattice plate at a position overlapping the opening 74. In this manner, if a dust collecting bag is housed in the internal space of the dust collecting section 35, the dust collecting bag can be prevented from adhering to the opening 74 and blocking it. If a dust collecting device is housed in the internal space of the dust collecting section 35, and the dust collecting device has a filter, the reflector 72 can be placed between the filter and the opening 74. In the case of a cyclone-type dust collecting device, the reflector 72 can be placed between the exhaust port of the cyclone section and the opening 74.

[0041] (Variation of the Third Embodiment) The intake side sound-reducing section 71 of the third embodiment shown in Figure 8 may further include a sound-absorbing material that covers at least a portion of at least one of the outer surface and the inner surface of the straight pipe section 41a of the sound-reducing pipe 41.

[0042] (Fourth Embodiment) Figure 10 is a longitudinal cross-sectional view showing an exhaust-side sound-reducing section 37X of a vacuum cleaner body according to a fourth embodiment. In Figure 10, elements similar to those in Figure 5 are designated by the same reference numerals. In the fourth embodiment, the exhaust-side sound-reducing section 37X includes the same sound-reducing tube 51 as in the first embodiment and a sound-absorbing material 58 provided in the expansion chamber 57 so as to externally cover the multiple through-holes 53 of the sound-reducing tube 51. In the fourth embodiment, sound-absorbing materials 59 and 60 are also provided in the first expansion section 33C and the second expansion section 33D. The sound-absorbing material 59 is disc-shaped and is attached to the partition wall 21 within the first expansion section 33C. The sound-absorbing material 60 is attached along the inner surface of the tapered portion 7 of the housing 5 within the second expansion section 33D. Other configurations of the fourth embodiment are similar to those of the first embodiment.

[0043] The sound absorbing material 58 may be provided without gaps in the expansion chamber 57. The sound absorbing material 59 may be formed in a cup shape with the partition wall 21 side as its bottom and the first thin housing portion 8 side as its periphery. The sound absorbing material 59 may be provided without gaps in the first expansion portion 33C, although this will result in a slight decrease in breathability. The sound absorbing material 60 may be provided without gaps in the second expansion portion 33D, although this will result in a slight decrease in breathability. Note that only one of the three sound absorbing materials 58, 59, and 60 may be provided, or any two of them may be provided in combination.

[0044] Fifth Embodiment Fig. 11 is a vertical cross-sectional view showing an exhaust-side sound-reducing section 61 of a vacuum cleaner body according to a fifth embodiment. In Fig. 11, elements that are the same as those in Fig. 5 are given the same reference numerals. The fifth embodiment differs from the first embodiment only in the configuration of the exhaust-side sound-reducing section 61; the other configurations of the fifth embodiment are the same as those of the first embodiment. Below, the differences between the fifth embodiment and the first embodiment will be mainly described.

[0045] As shown in FIG. 11 , in the fifth embodiment, the exhaust-side sound attenuation section 61 includes a sound attenuation pipe 62 having a bellows tube section 62a and a tapered section 51b. The bellows tube section 62a of the sound attenuation pipe 62 has a plurality of expansion spaces 62b, the internal space of which expands in a direction perpendicular to the central axis 40 of the sound attenuation pipe 62, spaced at predetermined intervals along the central axis 40. The sound attenuation pipe 62 is not flexible. In this embodiment, the expansion spaces 62b are formed in an annular shape in the circumferential direction of the bellows tube section 62a, and two expansion spaces 62b are provided along the central axis 40, spaced at a predetermined interval L1. In this embodiment, the interval L1 is approximately equal to the width L2 of the expansion spaces 62b along the central axis 40. However, the interval L1 may be shorter than the width L2, thereby increasing the number of expansion spaces 62b to three or more. Alternatively, the expansion spaces 62b may not be annular but may be spiral, arc-shaped, or the like, and the number of expansion spaces 62b may be one.

[0046] Regarding the spacing between the bellows pipe portion 62a and the first thin housing portion 8, the spacing a between the expansion space portion 62b of the bellows pipe portion 62a and the first thin housing portion 8 is narrow, and the spacing b between the portion where the expansion space portion 62b of the bellows pipe portion 62a does not exist and the first thin housing portion 8 is wide. As an example, the width a can be approximately half the width b. The first exhaust path 33A inside the bellows pipe portion 62a partially has the expansion space portion 62b, which can attenuate sound waves (noise) passing through the first exhaust path 33A compared to when the expansion space portion 62b does not exist. Furthermore, the second exhaust path 33B also has a portion with a narrow spacing a and a portion with a wide spacing b in the direction of the central axis 40, which can attenuate sound waves (noise) passing through the second exhaust path 33B compared to when the width of the second exhaust path 33B is constant (when the width is uniform to either the spacing a or the spacing b). In this embodiment, one expansion section 33E having a wide gap b is provided in the second exhaust passage 33B between the bellows tube 62a and the first thin housing section 8. Therefore, in addition to the first expansion section 33C and the second expansion section 33D, the expansion section 33E serves as a third expansion section.

[0047] (Modification of Fifth Embodiment) FIG. 12 is a longitudinal cross-sectional view showing a first modification of the fifth embodiment. In FIG. 12, elements similar to those in FIG. 11 are denoted by the same reference numerals. The exhaust-side sound-attenuating section 71 of this modification of the fifth embodiment includes the same sound-attenuation tube 62 as in the fifth embodiment and a sound-absorbing material 72 covering the inner surface of the expansion space 62b of the sound-attenuation tube 62. In this modification, the annular sound-absorbing material 72 is provided on the entire inner surface of the annular expansion space 62b. However, the sound-absorbing material 72 may be provided on only a portion of the inner surface of the expansion space 62b. In this modification, the thickness of the sound-absorbing material 72 is approximately half the depth c of the expansion space 62b (the depth in a direction perpendicular to the central axis 40), but may be equal to the depth c of the expansion space 62b. By disposing the sound-absorbing material 72 in the expansion space 62b, sound waves (noise) passing through the first exhaust passage 33A can be absorbed by the sound-absorbing material 72, further improving sound-attenuation performance. The sound-absorbing material may be provided so as to cover at least a portion of at least one of the inner and outer surfaces of the sound-attenuation tube 62. For example, the sound-absorbing material may be provided on the outer surface of the sound-attenuation tube 62 of the expansion section 33E. Furthermore, as in the example shown in FIG. 10 , the sound-absorbing material may also be provided on the first expansion section 33C and the second expansion section 33D.

[0048] (Sixth embodiment) Fig. 13 is a vertical cross-sectional view showing an exhaust-side sound-reducing section 81 of a vacuum cleaner body according to a sixth embodiment. In Fig. 13, elements that are the same as those in Fig. 5 are given the same reference numerals. The sixth embodiment differs from the first embodiment only in the configuration of the exhaust-side sound-reducing section 81; the other configurations of the sixth embodiment are the same as those of the first embodiment. Below, the differences between the sixth embodiment and the first embodiment will be mainly described.

[0049] As shown in FIG. 13 , in the sixth embodiment, an exhaust-side sound attenuation unit 81 includes a sound attenuation tube 82 having two tapered portions 51b and 82a. In the sound attenuation tube 82, the tapered portion 51b at one end is the second tapered portion 51b similar to that in the first embodiment, and the tapered portion 82a at the other end (hereinafter sometimes referred to as the third tapered portion 82a) is connected to the other end of the second tapered portion 51b. In this embodiment, the inclination of the tapered inner surface of the third tapered portion 82a with respect to the central axis 40 is gentler than that of the second tapered portion 51b, and the length of the third tapered portion 82a in the direction of the central axis 40 is longer than that of the second tapered portion 51b. By providing the sound attenuation tube 82 with a long third tapered portion 82a, sound waves (noise) passing through the third tapered portion 82a are attenuated as they reflect off the inner surface of the third tapered portion 82a. The third tapered portion 82a is located between the first expanding portion 33C and the second expanding portion 33D, and this configuration is also the same in Modifications 1 to 4 of the sixth embodiment, which will be described later.

[0050] (Variation 1 of Sixth Embodiment) FIG. 14 is a longitudinal cross-sectional view showing Variation 1 of the sixth embodiment. In FIG. 14, elements similar to those in FIG. 13 are assigned the same reference numerals. The exhaust-side sound-reducing section 91 of Variation 1 of the sixth embodiment includes the same sound-reducing tube 82 as in the sixth embodiment and a sound-absorbing material 92 covering the inner surface of the third tapered section 82a of the sound-reducing tube 82. In Variation 1, the inner surface of the third tapered section 82a is covered with a cylindrical sound-absorbing material 92. However, for example, it may be covered with a semi-cylindrical sound-absorbing material 92, or it may be covered in parts with multiple sound-absorbing materials 92. In Variation 1, the inner surface of the other end of the third tapered section 82a is not covered with the sound-absorbing material 92, but it may be covered. In Variation 1, by disposing the sound-absorbing material 92 on the inner surface of the third tapered section 82a, sound waves (noise) passing through the first exhaust passage 33A can be absorbed by the sound-absorbing material 92, thereby further improving sound reduction performance. Note that a sound-absorbing material may be provided on at least a portion of at least one of the inner and outer surfaces of the third tapered portion 82a. For example, a sound-absorbing material may be provided on the outer surface of the third tapered portion 82a. In this case, by providing a plurality of annular sound-absorbing materials having a certain thickness (for example, a thickness approximately half the distance between the third tapered portion 82a and the first thin housing portion 8) on the outer surface of the third tapered portion 82a at intervals in the direction of the central axis 40, one or more expansion portions can be formed between the two sound-absorbing materials in the second exhaust path 33B. This makes it possible to easily provide one or more expansion portions in the second exhaust path 33B outside the tapered portion 82a without processing the third tapered portion 82a into a shape such as a bellows pipe.

[0051] (Variation 2 of the Sixth Embodiment) FIG. 15 is a longitudinal cross-sectional view showing Variation 2 of the sixth embodiment. In FIG. 15, elements similar to those in FIG. 13 are designated by the same reference numerals. In this Variation 2, the sound attenuation tube 102 of the exhaust-side sound attenuation unit 101 includes the second tapered portion 51b similar to that of the sixth embodiment and a third tapered portion 102a having a plurality of through holes 102b penetrating the inner and outer surfaces. In this Variation 2, noise generated on the electric suction machine 34 side is transmitted inside the sound attenuation tube 102 and introduced into the second exhaust path 33B through the plurality of through holes 102b of the sound attenuation tube 102. A portion of the noise is eliminated by acoustic interference within the second exhaust path 33B, thereby reducing the noise level. Although not shown, a sound attenuation cover such as the sound attenuation cover 56 of FIG. 5 may be provided on the outer surface of the third tapered portion 102a to cover the plurality of through holes 102b from the outside.

[0052] (Variation 3 of Sixth Embodiment) Figure 16 is a longitudinal cross-sectional view showing Variation 3 of the sixth embodiment. In Figure 16, elements similar to those in Figure 15 are assigned the same reference numerals. In this Variation 3, the sound attenuation tube 102 of the exhaust-side sound attenuation section 103 is configured in the same manner as in Variation 2 of the sixth embodiment. This exhaust-side sound attenuation section 103 further includes a sound-absorbing material 104 covering the outer surface of the third tapered section 102a of the sound attenuation tube 102. The multiple through-holes 102b of the third tapered section 102a are externally covered by the sound-absorbing material 104. In this Variation 3, noise generated on the electric suction machine 34 side is transmitted to the inside of the sound attenuation tube 102 of the exhaust-side sound attenuation section 101 and is absorbed by the sound-absorbing material 104 through the multiple through-holes 102b of the sound attenuation tube 102, thereby reducing the noise level. Although not shown, a sound-absorbing cover similar to the sound-absorbing cover 56 shown in Fig. 5 may be provided on the outer surface of the sound-absorbing pipe 102 so as to cover the sound-absorbing material 104 from the outside. Alternatively, the thickness of the sound-absorbing material 104 may be partially changed to form recesses and protrusions on the surface of the sound-absorbing material 104, so that an expanded portion is formed in the second exhaust path 33B of the recess. Alternatively, the sound-absorbing material 104 may be provided so as to cover at least a portion of at least one of the inner and outer surfaces of the sound-absorbing pipe 102.

[0053] (Variation 4 of Sixth Embodiment) In order to reduce the exhaust pressure loss in the sound attenuation pipe 82 of the sixth embodiment (see FIG. 13), a plurality of through holes may be provided on the other end side of the third tapered portion 82a. The same applies to Variations 1-3 of the sixth embodiment (see FIGS. 14 to 16).

[0054] Seventh Embodiment Fig. 17 is a vertical cross-sectional view of an exhaust-side sound-reducing section 105 of a seventh embodiment. In Fig. 17, elements that are the same as elements in Fig. 5 are given the same reference numerals. The seventh embodiment differs from the first embodiment only in the configuration of the exhaust-side sound-reducing section 105, and the other configurations of the seventh embodiment are the same as those of the first embodiment. Below, the differences between the fourth embodiment and the first embodiment will be mainly described.

[0055] As shown in FIG. 17 , in the seventh embodiment, the exhaust-side sound attenuation section 105 includes a sound attenuation pipe 106. The sound attenuation pipe 106 includes a straight pipe section 106a with constant inner and outer diameters, a tapered section 51b connected to one end of the straight pipe section 106a, and an inverse tapered section 106b connected to the other end of the straight pipe section 106a. The straight pipe section 106a does not have multiple through holes. The inverse tapered section 106b has a cross section perpendicular to the central axis 40 of the sound attenuation pipe 106 that increases in size at a constant rate toward the downstream side (the other end) in the airflow direction. In the fourth embodiment, wind noise generated at the other end of the sound attenuation pipe 106 can be reduced by providing the other end of the sound attenuation pipe 106 with the inverse tapered section 106b, thereby lowering the noise level. The inverse tapered portion 106b is located between the first expanding portion 33C and the second expanding portion 33D, and this configuration is also the same in Modifications 1 and 2 of the seventh embodiment, which will be described later.

[0056] 17, the opening of the inverse tapered portion 106b of the sound attenuation tube 106 in a cross section perpendicular to the central axis 40 increases at a constant rate toward the other end, but the opening of the inverse tapered portion 106b may also increase exponentially toward the other end. For example, the inverse tapered portion 106b may be formed in a bell shape like the opening of a trumpet.

[0057] (Variation 2 of Seventh Embodiment) In the seventh embodiment, a sound-absorbing material may be provided on at least a portion of the inner surface of the sound attenuation tube 106, or a plurality of through-holes may be provided that penetrate the inner and outer surfaces of the sound attenuation tube 106. Furthermore, a sound-absorbing material may be provided on the portion of the outer surface of the sound attenuation tube 106 that has the through-hole. When a through-hole is provided, a sound-absorbing cover similar to the sound-attenuation cover 56 shown in FIG. 5 may be provided on the outer surface of the sound attenuation tube 106 so as to cover the through-hole from the outside. Furthermore, when a sound-absorbing material is provided on the outer surface of the straight tube portion 106a of the sound attenuation tube 106, a plurality of annular sound-absorbing materials having a certain thickness (for example, a thickness of about half the distance between the straight tube portion 106a and the first thin housing portion 8) may be provided at intervals in the direction of the central axis 40, thereby forming an expansion portion between the two sound-absorbing materials of the second exhaust path 33B. Alternatively, a sound absorbing material having recesses and protrusions on its surface may be provided on substantially the entire outer surface of the straight pipe portion 106a, and an expansion portion may be formed in the recessed second exhaust passage 33B.

[0058] Japanese Patent Application Laid-Open Publication No. 2001-218706 discloses a conventional vacuum cleaner comprising a vacuum cleaner main body and a suction tool connected to one end (front) of the vacuum cleaner main body. The vacuum cleaner main body includes an electric blower chamber containing a small electric blower, a dust collection chamber provided at one end of the electric blower chamber so as to communicate with the electric blower chamber, and a power supply component storage chamber provided at the other end (rear) of the electric blower chamber so as to communicate with the electric blower chamber. This vacuum cleaner is said to be able to reduce noise during operation by providing multiple recesses and protrusions inside the power supply component storage chamber.

[0059] In the case of the electric vacuum cleaner disclosed in JP 2001-218706 A, the outer diameter of the vacuum cleaner body is small, and the vacuum cleaner body itself serves as the handle, making it compact and easy to use, but the ventilation passage that circulates air inside the vacuum cleaner body cannot be made long. As a result, the ventilation passage inside the power supply component storage chamber, which is provided with multiple recesses and projections, is short, and the sound-deadening effect of the multiple recesses and projections cannot be fully achieved.

[0060] The electric vacuum cleaners according to the first to seventh embodiments described above are also electric vacuum cleaners that have been made in consideration of the above circumstances.

[0061] According to the electric vacuum cleaners according to the first to seventh embodiments described above, noise can also be reduced.

[0062] Eighth Embodiment Figure 18 is a longitudinal cross-sectional view showing an exhaust-side sound-reducing section 37 of an eighth embodiment. In Figure 18, elements similar to those in Figure 5 are assigned the same reference numerals. The eighth embodiment includes an exhaust-side sound-reducing section 37 structurally identical to that of the first embodiment, and the length L11 of the exhaust-side sound-reducing section 37 in the direction of the central axis 40 is set to be at least twice the length L12 of the first expansion section 33C, which is the folded-back section of the ventilation passage 33, in the direction of the central axis 40. The remaining configuration of the eighth embodiment is similar to that of the first embodiment.

[0063] In this embodiment, the relationship between the length L11 of the straight pipe portion 51a of the sound attenuation tube 51 in the direction of the central axis 40 and the length L12 of the first expansion portion 33C in the direction of the central axis 40 is as follows: If the length L11 of the straight pipe portion 51a in the direction of the central axis 40 is too short relative to the length L12 of the first expansion portion 33C, the air discharged from the other end opening 37b of the straight pipe portion 51a is likely to turn back (take a shortcut) without hitting the partition wall 21 of the first thin housing portion 8, which effectively shortens the overall length of the ventilation passage 33 and reduces the noise reduction effect. Also, if the length L11 is too long relative to the length L12, the other end opening 37b of the straight pipe portion 51a is too close to the partition wall 21, which reduces the spatial volume of the first expansion portion 33C and reduces the noise reduction effect of the first expansion portion 33C. Therefore, the relationship between the length L11 and the length L12 may be 2 × (L12) ≦ L11 ≦ 3 × (L12). Furthermore, when the length of the first thin housing 8 is length b, L12 may be "one-third or less" of length b. In this case, the straight pipe portion 51a is inserted into the first thin housing 8 to "two-thirds or more" of the length b of the first thin housing 8. Even in this configuration, air discharged from the other end opening 37b of the straight pipe portion 51a is less likely to fold back (take a shortcut) without hitting the partition wall 21 of the first thin housing 8. This prevents the spatial volume of the first expansion portion 33C from becoming too small, thereby achieving a noise reduction effect in the first expansion portion 33C.

[0064] Ninth Embodiment Figure 19 is a longitudinal cross-sectional view of an exhaust-side sound-reducing section 1101 of the ninth embodiment. In Figure 19, elements similar to those in Figure 5 are assigned the same reference numerals. The exhaust-side sound-reducing section 1101 of the fifth embodiment includes a sound-reducing pipe 51 structurally identical to those of the first embodiment, and a sound-absorbing material 1102. Furthermore, in this embodiment, sound-absorbing materials 1103 and 1104 are also provided in the first expansion section 33C and the second expansion section 33D. The other configurations of the ninth embodiment are generally similar to those of the first embodiment.

[0065] The sound-absorbing material 1102 is provided inside the sound-reducing cover 56 and is wrapped around the outer surface of the straight tube portion 51a of the sound-reducing tube 51. The sound-absorbing material 1103 provided inside the first expansion portion 33C is attached to the partition wall 21 so as to face the other-end opening 37b of the sound-reducing tube 51. The sound-absorbing material 1104 provided inside the second expansion portion 33D is attached in the circumferential direction along the inner surface of the tapered portion 7 of the housing 5. With this configuration, the sound-reducing effect of the multiple sound-absorbing materials 1102, 1103, and 1104 is added to the sound-reducing effect of the first embodiment, thereby further reducing noise. Note that at least one of the multiple sound-absorbing materials 1102, 1103, and 1104 may be provided.

[0066] Tenth Embodiment FIG. 20 is a longitudinal cross-sectional view showing an exhaust-side sound-reducing unit of a tenth embodiment. FIG. 21 is a longitudinal cross-sectional view partially enlarged from FIG. 20 . In FIGS. 20 and 21 , elements similar to those in FIG. 3 are designated by the same reference numerals. In the case of the vacuum cleaner main body 120 of the tenth embodiment, as shown in FIG. 20 , the internal space of the first thin housing 8 is connected to the internal space of the second thin housing 10, which is narrower than the internal space of the first thin housing 8, and the central axis 121 of the second thin housing 10 is inclined at an angle α with respect to the central axis 40 of the first thin housing 8. The angle α is not particularly limited, but it is appropriate to set it at an angle (e.g., approximately 10° to 25°) that allows the user to easily grip the second thin housing 10 during cleaning. By making the second thin housing 10 thinner and more inclined than the first thin housing 8, the operability of the vacuum cleaner main body 120 is improved. This also applies to the first to third, eighth, and ninth embodiments.

[0067] In the tenth embodiment, the exhaust-side sound attenuation section 111 includes a sound attenuation tube 115 having a first pipe section 112 within the first thin housing section 8, a second pipe section 113 that is thinner than the first pipe section 112 and that is provided from the inside of the other end side of the first thin housing section 8 to near the middle in the longitudinal direction of the second thin housing section 10, and a tapered section 114 that is provided between the first pipe section 112 and the second pipe section 113 and that becomes thinner toward the downstream side (the other end side) in the airflow direction. As in the first embodiment, the sound attenuation tube 115 has a plurality of through holes 53 provided in a range from the middle to one end side in the direction of the central axis 40 of the first pipe section 112, and a tapered section 51b connected to an end portion on the one end side of the first pipe section 112 (see FIG. 20 ).

[0068] 21 , the second tube section 113 of the sound attenuation tube 115 has a straight tube section 113a provided on the central axis 40, and an inclined tube section 113b arranged on a central axis 121 inclined at an angle α with respect to the central axis 40 and connected to the end section on the other end side of the straight tube section 113a. The other end of the inclined tube section 113b forms the other-end opening 116 of the sound attenuation tube 115. Furthermore, the internal space of the second thin casing section 10 on the other end side of the other-end opening 116 forms a first expansion section 133C serving as a folded section, and the internal space between the first thin casing section 8 and the tapered section 114 of the sound attenuation tube 115 forms a third expansion section 122.

[0069] 21 , the straight tube portion 113a of the second tube portion 113 of the sound attenuation tube 115 extends from the other end side of the first thin casing portion 8, past the bent portion 9, to one end side of the second thin casing portion 10. The inclined tube portion 113b of the second tube portion 113 extends from one end side of the second thin casing portion 10 to near the middle portion in the direction of the central axis 121 of the second thin casing portion 10. The length in the direction of the central axis 121 of the second thin casing portion 10 is approximately equal to the sum of the length L3 of the inclined tube portion 113b in the direction of the central axis 121 of the second thin casing portion 10 and the length L4 of the first expansion portion 133C in the direction of the central axis 121 of the second thin casing portion 10. In FIG. 13 , the length L3 of the inclined tube portion 113b is more than half the sum of L3 and L4.

[0070] If the length L3 of the inclined pipe portion 113b is too short relative to the length L4 of the first expansion portion 133C, the air discharged from the other end opening 116 of the inclined pipe portion 113b is likely to turn back (take a shortcut) without hitting the end wall 10a of the second thin housing portion 10, which effectively shortens the overall length of the ventilation passage 33 and reduces the noise reduction effect. Also, if the length L3 is too long relative to the length L4, the other end opening 116 of the inclined pipe portion 113b is too close to the end wall 10a of the second thin housing portion 10, which reduces the spatial volume of the first expansion portion 133C and reduces the noise reduction effect of the first expansion portion 133C. Therefore, the relationship between the lengths L3 and L4 may be L4≦L3≦2×(L4).

[0071] In the tenth embodiment, the spatial volume of the first expansion section 133C set in this manner is equal to or greater than the spatial volume of the first expansion section 33C (see FIG. 3) in the first embodiment. This is because the diameter of the first expansion section 133C in the tenth embodiment is smaller than the diameter of the first expansion section 33C in the first embodiment, and the length L4 is made longer than the length L2 to increase the space of the folded-back section. In the tenth embodiment, the air folded back by the first expansion section 133C in the second thin housing 10 flows through the annular ventilation path between the second pipe section 113 and the second thin housing 10 and enters the third expansion section 122 in the first thin housing 8, thereby reducing noise in the third expansion section 122. Furthermore, when the overall length of the housing 123 in the direction of the central axis 40 is constant, by inclining the central axis 121 of the second thin housing 10 with respect to the central axis 40 of the first thin housing 8, rather than extending the second thin housing 10 straight along the central axis 40, the overall length of the ventilation passage 33 can be increased, and the noise reduction effect can be more easily improved. This also applies to the first to third, eighth and ninth embodiments.

[0072] Japanese Patent Application Laid-Open Publication No. 2001-218706 discloses a conventional vacuum cleaner comprising a vacuum cleaner main body and a suction tool connected to one end (front) of the vacuum cleaner main body. The vacuum cleaner main body includes an electric blower chamber containing a small electric blower, a dust collection chamber provided at one end of the electric blower chamber so as to communicate with the electric blower chamber, and a power supply component storage chamber provided at the other end (rear) of the electric blower chamber so as to communicate with the electric blower chamber. This vacuum cleaner is said to be able to reduce noise during operation by providing multiple recesses and protrusions inside the power supply component storage chamber.

[0073] In the case of the electric vacuum cleaner disclosed in JP 2001-218706 A, the outer diameter of the vacuum cleaner body is small, and the vacuum cleaner body itself serves as the handle, making it compact and easy to use, but the ventilation passage that circulates air inside the vacuum cleaner body cannot be made long. As a result, the ventilation passage inside the power supply component storage chamber, which is provided with multiple recesses and projections, is short, and the sound-deadening effect of the multiple recesses and projections cannot be fully achieved.

[0074] The vacuum cleaners according to the first to third embodiments and the eighth to tenth embodiments described above are vacuum cleaners that have been made in consideration of the above circumstances.

[0075] According to the electric vacuum cleaners of the first to third embodiments and the eighth to tenth embodiments described above, noise can also be reduced effectively.

[0076] An electric vacuum cleaner according to one aspect of the present invention includes, for example, the following electric vacuum cleaners. Note that the electric vacuum cleaner according to one aspect of the present invention also includes, to the extent not contradictory, a combination of any one of the electric vacuum cleaners according to any one of items 1 to 12 of the following first aspect, any one of the electric vacuum cleaners according to any one of items 1 to 9 of the following second aspect, and any one of items 1 to 16 of the following third aspect.

[0077] The electric vacuum cleaner according to the first aspect of the present invention comprises a cylindrical housing having an intake port and an exhaust port, a ventilation passage for directing air from the intake port to the exhaust port, an electric suction machine provided in the ventilation passage, and a sound-reducing section provided in the ventilation passage downstream of the electric suction machine in the airflow direction to reduce noise including the driving sound of the electric suction machine, the sound-reducing section comprising a sound-reducing tube having a ventilating structure on at least a portion of its surrounding surface.

[0078] In the electric vacuum cleaner according to the second aspect of the first aspect, in the first aspect of the first aspect, the ventilation structure is a plurality of through holes that penetrate the inner and outer surfaces of the sound reduction tube.

[0079] The vacuum cleaner according to the third aspect of the first aspect is based on the second aspect of the first aspect, wherein the sound reduction section further includes a sound absorbing material that covers at least a part of at least one of an outer surface and an inner surface of the sound reduction tube.

[0080] In the electric vacuum cleaner according to the fourth aspect of the first aspect, in any one of the first to third aspects of the first aspect, the sound reduction tube has a tapered portion whose opening narrows toward the downstream side in the airflow direction.

[0081] In the electric vacuum cleaner according to the fifth aspect of the first aspect, in the fourth aspect of the first aspect, the sound reduction section further has a sound absorbing material that covers at least a part of at least one of the outer surface and the inner surface of the tapered section of the sound reduction tube.

[0082] In the electric vacuum cleaner according to a sixth aspect of the first aspect, in addition to the fifth aspect of the first aspect, the sound reduction tube has a plurality of through holes that penetrate the inner and outer surfaces of the tapered portion.

[0083] In the electric vacuum cleaner according to the seventh aspect of the first aspect, in the first aspect of the first aspect, the sound reduction tube has one or more expansion space portions spaced apart in the central axis direction, in which the internal space expands in a direction perpendicular to the central axis of the sound reduction tube.

[0084] An eighth aspect of the first aspect of the electric vacuum cleaner is related to the seventh aspect of the first aspect, wherein the sound reduction section further includes a sound absorbing material that covers the inner surface of the expansion space section of the sound reduction tube.

[0085] In the electric vacuum cleaner according to paragraph 9 of the first aspect, in any one of paragraphs 1 to 3 of the first aspect, the sound reduction tube has an inverted tapered portion whose opening becomes larger toward the downstream side in the airflow direction.

[0086] In the electric vacuum cleaner according to item 10 of the first aspect, in any one of items 1 to 3 of the first aspect, the housing has a body portion in which the electric suction device is provided, and a thin housing portion that is located at a position away from the electric suction device and is thinner than the body portion, and the thin housing portion has a first thin housing portion connected to the body portion and a second thin housing portion that is thinner than the first thin housing portion and is connected to the end of the first thin housing portion opposite the body portion, and a partition wall is provided at the boundary between the first thin housing portion and the second thin housing portion to separate the internal space of the first thin housing portion from the internal space of the second thin housing portion, and an end wall is provided at the end of the second thin housing portion opposite the partition wall to seal the internal space of the second thin housing.

[0087] An electric vacuum cleaner according to item 11 of the first aspect comprises a vacuum cleaner body including a housing having an air intake port and an exhaust port, a ventilation passage through which air from the air intake port flows to the exhaust port, an electric suction machine provided in the ventilation passage, a dust collecting unit provided in the ventilation passage upstream of the electric suction machine in the airflow direction, an intake-side sound reducing unit provided in the ventilation passage between the dust collecting unit and the electric suction machine, and an exhaust-side sound reducing unit provided in the ventilation passage between the electric suction machine and the exhaust port, wherein the housing has a trunk portion in which the electric suction machine is provided, and a thin housing portion which is provided at a position away from the electric suction machine and is thinner than the trunk portion, The exhaust port is provided near the electric suction device in the housing, and the ventilation path has a first exhaust path extending from the electric suction device to inside the thin housing portion and a second exhaust path that turns around inside the thin housing portion and extends to the exhaust port, has a first expansion section at the turning point between the first exhaust path and the second exhaust path and has a second expansion section midway along the second exhaust path, the exhaust-side sound-reducing section has a tapered section at the end of the first exhaust path on the upstream side in the airflow direction that widens its opening toward the upstream side in the airflow direction, and the thin housing portion has a first thin housing portion connected to the body portion and a second thin housing portion connected to the first thin housing portion.

[0088] The electric vacuum cleaner according to item 12 of the first aspect comprises a housing having an intake port and an exhaust port, a ventilation duct that directs air from the intake port to the exhaust port, an electric suction machine provided in the ventilation duct, a dust collection unit provided in the ventilation duct upstream of the electric suction machine in the airflow direction, an intake-side sound reduction unit provided between the dust collection unit in the ventilation duct and the electric suction machine, and an exhaust-side sound reduction unit provided in the ventilation duct between the electric suction machine and the exhaust port, and a suction port body connectable to the intake port of the vacuum cleaner body, and the housing comprises a body portion in which the electric suction machine is provided, and a dust collection unit provided at a position distant from the electric suction machine and further upstream than the body. the exhaust port is provided in the housing near the electric suction device; the ventilation path has a first exhaust path extending from the electric suction device to inside the thin housing and a second exhaust path that turns around inside the thin housing and extends to the exhaust port; the ventilation path has a first expansion part at the turning point between the first exhaust path and the second exhaust path and a second expansion part midway along the second exhaust path; the exhaust-side sound-reducing part has a tapered part whose opening widens toward the upstream side in the airflow direction at the end of the first exhaust path on the upstream side in the airflow direction; and the suction port body has a connecting pipe part that can be connected to the suction port of the vacuum cleaner body, and a suction port body-side sound-reducing part.

[0089] The electric vacuum cleaner according to the first aspect of the second aspect comprises a housing having an intake port and an exhaust port, an air passage through which air from the intake port flows to the exhaust port, an electric suction device provided in the air passage, and a sound-reducing section that forms part of the air passage downstream of the electric suction device in the airflow direction and reduces noise including the driving sound of the electric suction device, the sound-reducing section comprising a sound-reducing tube having a breathable structure on at least part of its peripheral surface, the intake port being provided at one end side in the direction of the central axis of the housing, and the sound-reducing tube having an other-end opening side in the direction of the central axis of the housing, the air passage comprising a first exhaust path between the electric suction device and the other-end opening and a second exhaust path between the sound-reducing tube and the housing, the second exhaust path having a folding portion that folding back air flowing out from the other-end opening, and the folding portion having a first expansion portion that diffuses the air flowing out from the other-end opening.

[0090] In the electric vacuum cleaner according to the second aspect of the second specification, in the first aspect of the second specification, the second exhaust passage has a second expansion section that is provided on one end side of the first expansion section and diffuses the air flowing through the second exhaust passage.

[0091] In the electric vacuum cleaner according to the third aspect of the second aspect, in the second aspect of the second aspect, the second expansion section is provided closer to the other end than the electric suction device.

[0092] The electric vacuum cleaner according to the fourth aspect of the second aspect is based on the third aspect of the second aspect, and the exhaust port is provided in a part of the housing closer to one end than the electric suction device.

[0093] In the electric vacuum cleaner according to the fifth aspect of the second aspect, in the fourth aspect of the second aspect, the ventilation structure is a plurality of through holes that penetrate the inner and outer surfaces of the sound reduction tube.

[0094] The vacuum cleaner according to a sixth aspect of the second aspect is the electric vacuum cleaner according to the fifth aspect of the second aspect, further comprising a sound absorbing material that covers at least a part of at least one of an outer surface and an inner surface of the sound reduction tube.

[0095] The vacuum cleaner according to item 7 of the second aspect is any one of items 2 to 6 of the second aspect, further comprising a sound-absorbing material provided in at least one of the first expansion section and the second expansion section.

[0096] The electric vacuum cleaner according to item 8 of the second aspect comprises a vacuum cleaner body including a housing having an air intake port and an exhaust port, a ventilation passage for directing air from the air intake port to the exhaust port, an electric suction machine provided in the ventilation passage, a dust collecting unit provided in the ventilation passage upstream of the electric suction machine in the airflow direction, an intake-side sound reducing unit provided in the ventilation passage between the dust collecting unit and the electric suction machine, and an exhaust-side sound reducing unit provided in the ventilation passage between the electric suction machine and the exhaust port, the housing having a body part in which the electric suction machine is provided and a thin housing part located at a position away from the electric suction machine and thinner than the body part, the exhaust port being provided in the housing The air passage has a first exhaust passage extending from the electric suction device to inside the thin housing portion and a second exhaust passage that turns around inside the thin housing portion and extends to the exhaust port, a first expansion section at the turning point between the first exhaust passage and the second exhaust passage and a second expansion section midway along the second exhaust passage, the exhaust-side sound-reducing section has a tapered section at the end of the first exhaust passage on the upstream side in the airflow direction, the tapered section having an opening that widens toward the upstream side in the airflow direction, and the thin housing portion has a first thin housing portion connected to the trunk portion and a second thin housing portion connected to the first thin housing portion and thinner than the first thin housing portion.

[0097] The electric vacuum cleaner according to the ninth aspect of the second aspect comprises a vacuum cleaner body including a housing having an air intake port and an exhaust port, a ventilation passage through which air from the air intake port flows to the exhaust port, an electric suction machine provided in the ventilation passage, a dust collecting unit provided in the ventilation passage upstream of the electric suction machine in the airflow direction, an intake-side sound reducing unit provided in the ventilation passage between the dust collecting unit and the electric suction machine, and an exhaust-side sound reducing unit provided in the ventilation passage between the electric suction machine and the exhaust port, and a suction port body connectable to the air intake port of the vacuum cleaner body, and the housing has a body portion in which the electric suction machine is provided and a thin housing portion provided at a position away from the electric suction machine and thinner than the body portion. The exhaust port is provided near the electric suction device in the housing, the ventilation path has a first exhaust path extending from the electric suction device to inside the narrow housing part and a second exhaust path that turns around inside the narrow housing part and extends to the exhaust port, has a first expansion section at the turning point between the first exhaust path and the second exhaust path and has a second expansion section midway along the second exhaust path, the exhaust side sound reduction section has a tapered section at the end of the first exhaust path on the upstream side in the airflow direction whose opening widens toward the upstream side in the airflow direction, and the suction port body has a rotating brush, a drive motor for the rotating brush, a connecting pipe section that can be connected to the intake port of the vacuum cleaner main body, and a suction port body side sound reduction section.

[0098] The electric vacuum cleaner according to the first aspect of the third aspect comprises a housing having an intake port and an exhaust port, a ventilation passage through which air from the intake port flows to the exhaust port, an electric suction machine provided in the ventilation passage, and a sound-reducing section that forms part of the ventilation passage downstream of the electric suction machine in the airflow direction and reduces noise including the driving sound of the electric suction machine, the sound-reducing section comprising a sound-reducing tube having a breathable structure on at least part of its surrounding surface, the intake port being provided at one end side in the direction of the central axis of the housing, the sound-reducing tube having an other-end opening side in the direction of the central axis of the housing, and the ventilation passage having a folding section that folds back the air flowing out from the other-end opening and guides it into the gap between the other-end opening and the housing.

[0099] In the electric vacuum cleaner according to the second aspect of the third aspect, in the first aspect of the third aspect, the ventilation structure is a plurality of through holes that penetrate the inner and outer surfaces of the sound reduction tube.

[0100] The vacuum cleaner according to the third aspect of the present invention is the electric vacuum cleaner according to the second aspect of the present invention, further comprising a sound absorbing material that covers at least a part of at least one of the outer surface and the inner surface of the sound reduction tube.

[0101] In the electric vacuum cleaner according to the fourth item of the third aspect, in the third item of the third aspect, the housing has a body portion in which the electric suction machine is provided, and a thin housing portion that is located away from the electric suction machine and is thinner than the body portion, and the other end opening and the folded portion of the ventilation passage are provided within the thin housing portion.

[0102] In the electric vacuum cleaner according to the fifth aspect of the third aspect, in the fourth aspect of the third aspect, the thin housing portion has a first thin housing portion connected to the body portion and a second thin housing portion that is thinner than the first thin housing portion and is connected to the end of the first thin housing portion opposite the body portion, and the other end opening and the folded portion of the ventilation passage are provided within the first thin housing portion or the second thin housing portion.

[0103] In the electric vacuum cleaner according to the sixth aspect of the third aspect, in the fifth aspect of the third aspect, the internal space of the second thin housing portion is formed narrower than the internal space of the first thin housing portion, and the sound-reducing tube has a first tube portion in the first thin housing portion and a second tube portion narrower than the first tube portion in the second thin housing portion.

[0104] In the electric vacuum cleaner according to the seventh aspect of the third aspect, in the sixth aspect of the third aspect, the length of the second tube portion in the direction of the central axis of the second thin housing portion is equal to or greater than the length of the folded portion in the direction of the central axis of the second thin housing portion.

[0105] In the vacuum cleaner according to the eighth aspect of the third aspect, in any one of the fifth to seventh aspects of the third aspect, the central axis of the second thin casing part is inclined with respect to the central axis of the first thin casing part.

[0106] In the electric vacuum cleaner according to the ninth aspect of the third aspect, in any one of the first to seventh aspects of the third aspect, the length of the sound reduction tube in the direction of the central axis is at least twice the length of the folded portion of the ventilation passage in the direction of the central axis.

[0107] In the electric vacuum cleaner according to item 10 of the third aspect, in items 6 or 7 of the third aspect, there is a tapered section between the first pipe section and the second pipe section that narrows toward the downstream side in the airflow direction, and the ventilation passage in the gap between the other end opening and the housing has an expansion section near the gap between the first narrow housing section and the tapered section.

[0108] The vacuum cleaner according to an eleventh aspect of the third aspect is the electric vacuum cleaner according to any one of the first to seventh aspects of the third aspect, further comprising a sound absorbing material provided at the folded portion.

[0109] A twelfth aspect of the third aspect is the electric vacuum cleaner according to any one of the first to seventh aspects of the third aspect, wherein the exhaust port is provided in the housing near the electric suction device.

[0110] In the electric vacuum cleaner according to item 13 of the third aspect, in items 1 or 2 of the third aspect, the housing has a body portion in which the electric suction machine is provided, and a thin housing portion that is located away from the electric suction machine and is thinner than the body portion, and the other end opening and the folded portion of the ventilation passage are provided within the thin housing portion.

[0111] In the electric vacuum cleaner according to item 14 of the third aspect, in any one of items 1 to 3 of the third aspect, the housing has a body portion in which the electric suction machine is provided, and a thin housing portion that is located at a position away from the electric suction machine and is thinner than the body portion, and the thin housing portion has a first thin housing portion connected to the body portion and a second thin housing portion that is thinner than the first thin housing portion and is connected to the end of the first thin housing portion opposite the body portion, and the other end opening and the folded portion of the ventilation passage are provided within the second thin housing portion.

[0112] The electric vacuum cleaner according to item 15 of the third aspect comprises a vacuum cleaner body including a housing having an air intake port and an exhaust port, a ventilation passage for directing air from the air intake port to the exhaust port, an electric suction machine provided in the ventilation passage, a dust collecting unit provided in the ventilation passage upstream of the electric suction machine in the airflow direction, an intake-side sound reducing unit provided in the ventilation passage between the dust collecting unit and the electric suction machine, and an exhaust-side sound reducing unit provided in the ventilation passage between the electric suction machine and the exhaust port, the housing having a body part in which the electric suction machine is provided and a thin housing part located at a position away from the electric suction machine and thinner than the body part, and the exhaust port The exhaust-side sound-reducing section has a tapered section whose opening widens toward the upstream side in the airflow direction at the end of the first exhaust path on the upstream side in the airflow direction, and the narrow housing section has a first narrow housing section connected to the body section and a second narrow housing section connected to the first narrow housing section via a bent section.

[0113] The electric vacuum cleaner according to item 16 of the third aspect comprises a vacuum cleaner body including a housing having an intake port and an exhaust port, a ventilation passage through which air from the intake port flows to the exhaust port, an electric suction machine provided in the ventilation passage, a dust collecting unit provided in the ventilation passage upstream of the electric suction machine in the airflow direction, an intake-side sound reducing unit provided in the ventilation passage between the dust collecting unit and the electric suction machine, and an exhaust-side sound reducing unit provided in the ventilation passage between the electric suction machine and the exhaust port, and a suction port body connectable to the intake port of the vacuum cleaner body, and the housing includes a body portion in which the electric suction machine is provided, and a suction port body which is provided at a position away from the electric suction machine and is thinner than the body The vacuum cleaner has a thin casing portion, and the exhaust port is provided at a position in the casing near the electric suction device. The ventilation path has a first exhaust path extending from the electric suction device to inside the thin casing portion and a second exhaust path that turns around inside the thin casing portion and extends to the exhaust port. The ventilation path has a first expansion portion at the turning point between the first exhaust path and the second exhaust path and a second expansion portion midway along the second exhaust path. The exhaust-side sound-reducing portion has a tapered portion at the end of the first exhaust path on the upstream side in the airflow direction, the opening of which widens toward the upstream side in the airflow direction. The suction port body has a rotating brush, a connecting pipe portion connectable to the suction port of the vacuum cleaner main body, and a suction port body-side sound-reducing portion.

[0114] Preferred aspects of the present invention also include combinations of any of the above-described aspects. In addition to the above-described embodiments, various modifications of the present invention are possible. These modifications should not be interpreted as not falling within the scope of the present invention. The present invention should include all modifications within the scope of the claims and their equivalents.

Claims

1. An electric vacuum cleaner comprising a cylindrical housing having an intake port and an exhaust port, a ventilation passage through which air from the intake port flows to the exhaust port, an electric suction machine provided in the ventilation passage, and a sound-reduction section provided in the ventilation passage downstream of the electric suction machine in the airflow direction for reducing noise including the driving sound of the electric suction machine, wherein the sound-reduction section is provided with a sound-reduction tube having a structure that allows ventilation on at least a portion of the surrounding surface.

2. The vacuum cleaner according to claim 1, wherein the breathable structure is a plurality of through holes penetrating the inner and outer surfaces of the sound-reducing tube.

3. The vacuum cleaner according to claim 2, wherein the sound reduction section further comprises a sound absorbing material covering at least a part of at least one of the outer surface and the inner surface of the sound reduction tube.

4. The vacuum cleaner according to any one of claims 1 to 3, wherein the sound reduction tube has a tapered section whose opening narrows toward the downstream side in the air flow direction.

5. The vacuum cleaner according to claim 4, wherein the sound-reducing portion further comprises a sound-absorbing material covering at least a portion of at least one of the outer surface and the inner surface of the tapered portion of the sound-reducing tube.

6. A vacuum cleaner as claimed in any one of claims 1 to 5, wherein the sound-reduction section forms part of the ventilation passage, the air intake is provided at one end side in the direction of the central axis of the housing, and the sound-reduction tube has an other-end opening at the other end side in the direction of the central axis of the housing, the ventilation passage has a first exhaust passage between the electric suction device and the other-end opening, and a second exhaust passage between the sound-reduction tube and the housing, the second exhaust passage has a folding section that folds back the air flowing out from the other-end opening, and the folding section has a first expansion section that diffuses the air flowing out from the other-end opening.

7. The vacuum cleaner according to claim 6, wherein the second exhaust passage has a second expansion portion that is provided on one end side of the first expansion portion and that diffuses the air flowing through the second exhaust passage.

8. The vacuum cleaner according to claim 7, wherein the second expansion section is provided on the other end side than the electric suction device.

9. The vacuum cleaner according to claim 8, wherein the exhaust port is provided in a part of the housing on one end side of the electric suction device.

10. The vacuum cleaner according to claim 7, further comprising a sound absorbing material provided on at least one of the first expansion section and the second expansion section.

11. A vacuum cleaner as claimed in any one of claims 1 to 5, wherein the sound reduction section forms part of the ventilation passage, the air intake is provided at one end side in the direction of the central axis of the housing, the sound reduction tube has an other end opening at the other end side in the direction of the central axis of the housing, and the ventilation passage has a folding section that turns back the air flowing out from the other end opening and guides it into the gap between the other end opening and the housing.

12. The vacuum cleaner according to claim 11, wherein the housing has a body portion in which the electric suction device is provided and a thin housing portion which is located away from the electric suction device and is thinner than the body portion, and the other end opening and the folded-back portion of the ventilation passage are provided within the thin housing portion.

13. The vacuum cleaner according to claim 11, wherein the length of the sound reduction tube in the direction of the central axis is at least twice the length of the folded portion of the ventilation passage in the direction of the central axis.

14. The vacuum cleaner according to claim 11, further comprising a sound absorbing material provided in the folded portion.

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