JP5280960B2 - Electric vacuum cleaner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum cleaner capable of reducing exhaust noise in response to the variation of an exhaust pressure without increasing exhaust loss. <P>SOLUTION: In the vacuum cleaner, when the exhaust pressure from an electric blower 27 does not reach a prescribed exhaust pressure, respective openings 94 are closed by a valve 95 and respective resonance spaces 91 do not communicate with a second exhaust air path 92. While making the respective resonance spaces 91 function as resonators, exhaust from the electric blower 27 is exhausted through a first exhaust air path 83 to an electric blower chamber. When the exhaust pressure from the electric blower 27 reaches the prescribed exhaust pressure, the respective openings 94 are opened by the valve 95 to make the respective resonance spaces 91 communicate with the second exhaust air path 92. While making the respective resonance spaces 91 and the second exhaust air path 92 function as an extension chamber, a part of the exhaust of the electric blower 27 is exhausted through the respective resonance spaces 91 and the second exhaust air path 92. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a vacuum cleaner that reduces exhaust noise from an electric blower.

  Conventionally, in this type of vacuum cleaner, a dust collection chamber and an electric blower chamber communicating with the dust collection chamber are partitioned before and after the hollow main body case. An electric blower is accommodated in the electric blower chamber. The outer peripheral side of the electric blower is covered with a case body, and an exhaust air passage for guiding the exhaust from the electric blower to the exhaust hole of the main body case is defined in the case body. And the exhaust noise is reduced by extending the length that the exhaust from the electric blower flows to the exhaust hole of the main body case by this exhaust air passage (see, for example, Patent Document 1).

Japanese Patent No. 3012729 (page 5-7, Fig. 4-5)

  However, the above-described electric vacuum cleaner has a problem that the exhaust loss increases due to the length of the exhaust air passage, and the suction force by the electric blower decreases.

  The present invention has been made in view of these points, and an object of the present invention is to provide a vacuum cleaner that can reduce exhaust noise in response to fluctuations in exhaust pressure without increasing exhaust loss.

  The present invention includes an electric blower chamber that houses an electric blower, a first exhaust air passage that guides exhaust from the electric blower to the electric blower chamber, and a resonance space that is formed in communication with the first exhaust air passage. A second exhaust air passage that communicates the resonance space with the electric blower chamber side, an opening that communicates the resonance space and the second exhaust air passage, and the opening that is disposed in the opening and reaches a predetermined exhaust pressure. And a communication device for communicating the resonance space with the second exhaust air passage.

  According to the present invention, when the exhaust pressure from the electric blower does not reach a predetermined exhaust pressure, the resonance space and the second exhaust air passage are not communicated by the communication device, and the electric blower is operated while the resonance space acts as a resonator. Is exhausted to the electric blower chamber via the first exhaust air passage, so that it is possible to reduce peak noise that is likely to occur when the exhaust pressure is relatively low, and the exhaust pressure from the electric blower is a predetermined exhaust pressure. When the frequency reaches the resonance space, the resonance device and the second exhaust air passage communicate with each other by the communication device, and the resonance space and the second exhaust air passage function as an expansion chamber, and a part of the exhaust of the electric blower is passed through the resonance space and the second exhaust air passage. Since the exhaust air is exhausted through the exhaust air passage, wideband noise such as wind noise that is likely to occur when the exhaust pressure is relatively high can be reduced. In response to fluctuations in exhaust pressure it becomes possible to reduce the exhaust noise.

It is a perspective view showing a low exhaust pressure state of the vacuum cleaner of one embodiment of the present invention with a part cut away. It is a perspective view which partially cuts out the high exhaust pressure state of a vacuum cleaner same as the above. It is a longitudinal cross-sectional view which shows a part of vacuum cleaner same as the above. It is a perspective view which expands and shows the communication apparatus of a vacuum cleaner same as the above. It is a longitudinal cross-sectional view which shows a vacuum cleaner same as the above. It is a perspective view which shows a vacuum cleaner same as the above.

  The configuration of an embodiment of the present invention will be described below with reference to FIGS.

  In FIG. 6, reference numeral 11 denotes a so-called canister-type vacuum cleaner, and the vacuum cleaner 11 has a pipe portion 12 and a cleaner body 13 to which the pipe portion 12 is detachably connected.

  The pipe part 12 is provided on the distal end side of the hose body 16, the connecting pipe part 15 connected to the cleaner body 13, the flexible hose body 16 communicating with the distal end side of the connecting pipe part 15. The hand operating section 17, the extension pipe 18 detachably connected to the distal end side of the hand operating section 17, and the floor brush 19 as a suction port body detachably connected to the distal end side of the extension pipe 18. It has.

  On the hand operating portion 17, a gripping portion 21 protrudes toward the hose body 16, and the gripping portion 21 is provided with a plurality of setting buttons 22 for operation.

  Further, as shown in FIGS. 5 and 6, the cleaner main body 13 includes a main body case 25 formed in a hollow shape with synthetic resin or the like, and on the rear side of the partition wall 26 formed inside the main body case 25. An electric blower 27 and an electric blower chamber 28 that houses a main body control unit (not shown) as a control means for controlling the operation of the electric blower 27, and a power supply unit (not shown) for supplying electric power to the electric blower 27 and the like are housed. A power supply chamber (not shown) is partitioned, and a main dust collection chamber 33 communicating with the suction side of the electric blower 27 is defined on the front side of the partition wall 26 through a communication port 31 provided in the partition wall 26. In the main body dust collecting chamber 33, for example, a dust collecting section 34 such as a dust collecting bag, a filter, or a dust collecting cup as a dust collecting device is disposed.

  The main body case 25 is provided with a main body suction port 35 communicating with the upstream side of the main body dust collecting chamber 33 and connected to the connecting pipe portion 15 at the front portion. Further, the main body case 25 includes a main body lid 36 capable of opening and closing the main body dust collecting chamber 33 at the upper part on the front side. Further, a plurality of exhaust holes 37 communicating with the electric blower chamber 28 are formed in the rear part of the main body case 25. Further, traveling wheels 38 (only one of which is shown) for allowing the cleaner main body 13 to travel on the floor surface or the like are rotatably attached to both side portions on the rear side of the main body case 25. A turning wheel 39 for turning the main body case 25 during traveling is attached to the lower portion on the front side of the main body case 25 so as to be turnable.

  As shown in FIGS. 1 and 2, the electric blower 27 includes a case body 41 as an electric blower main body, and a fan cover 42 attached to the front end side which is one end side of the case body 41. An electric motor unit 43 as a motor unit is accommodated in the body 41, and a rectifying plate (diffuser) (not shown) and a centrifugal fan 45 are accommodated between the case body 41 and the fan cover. The electric blower 27 has a cover body 46 attached around it. Although not shown, the cover body 46 is elastically supported with respect to the main body case 25 via an elastic member or the like.

  The case body 41 includes, for example, a case main body 48 formed in a substantially bottomed cylindrical shape with metal, synthetic resin, or the like, and a case plate portion (not shown) attached to a front end portion which is one end portion of the case main body 48. ing.

  A cylindrical motor head portion for rotatably supporting the rear end side of the electric motor portion 43 at the center position of the other end portion, that is, the rear end portion (bottom portion) opposite to the fan cover 42 of the case body 48. 51 is formed so as to protrude rearward coaxially. In addition, a plurality of, for example, four exhaust ports 52 are formed in the outer peripheral surface of the case body 48, and are electrically connected to the power feeding unit and the motor unit 43 at positions different from the exhaust ports 52. A brush device 53 is attached. Furthermore, one end of the case main body 48 protrudes over the entire circumference in a flange shape in the radial direction.

  The exhaust ports 52 are spaced apart from each other in the circumferential direction. In the present embodiment, for example, two exhaust ports 52 are arranged on the upper and lower sides on both sides in the left-right width direction.

  The case plate portion is disposed at one end of the case body 48 along the diameter of the case body 48. Further, the case plate portion is formed with a shaft support portion for rotatably supporting the front end side of the electric motor portion 43 inside, and a rectifying plate is fixed to the outside of the shaft support portion.

  The fan cover 42 is formed in a substantially covered cylindrical shape with metal or the like, and the rear end side is fixed to the flange-shaped front end portion of the case main body 48, so that it is integrated with the case body 41. Further, the fan cover 42 is formed with a circular suction port 55 serving as an intake port of the electric blower 27 at the center position on the front end side.

  The electric motor unit 43 includes a long rotating shaft 57. The rotating shaft 57 is rotated by bearings (not shown) accommodated in the motor head portion 51 of the case body 48 and the shaft support portion of the case plate portion, respectively. It is held freely. Since the electric motor unit 43 is an inner rotor type, a detailed description of the configuration is omitted.

  The rectifying plate rectifies the air blown to the outer peripheral side by the rotation of the centrifugal fan 45 and guides it into the case main body 48 of the case body 41. The front end side of the rotating shaft 57 is inserted through the central portion of the current plate.

  The centrifugal fan 45 is fixed to the front end side of the rotating shaft 57 and can rotate integrally with the rotating shaft 57. A circular intake opening 62 that is airtightly connected to the suction port 55 of the fan cover 42 is formed in the center of the front end side of the centrifugal fan 45.

  On the other hand, as shown in FIGS. 1 to 4, the cover body 46 is formed in a substantially cylindrical shape with, for example, a synthetic resin and covers the entire outside of the electric blower 27. The cover body 46 is formed in a substantially double cylinder shape by an outer cylinder portion 65 that defines the outer side and an inner cylinder portion 66 that defines the inner side. The cover body 46 is divided into a plurality of parts at arbitrary locations, and is configured by combining these divided parts together.

  The outer cylinder portion 65 includes a front surface portion 71 that is a circular plane upstream surface portion that forms the front surface (upstream surface) of the cover body 46, and a circular flat surface downstream surface portion that forms the rear surface (downstream surface) of the cover body 46. A certain rear surface portion 72 and a cylindrical outer peripheral surface portion 73 that air-tightly connects the front surface portion 71 and the rear surface portion 72 are integrally provided.

  A circular opening 75 is formed in the center of the front surface 71 so as to be airtightly connected to the communication port 31 (FIG. 5) via an inducer 74 that is a rectifier. The opening 75 serves as an air inlet of the cover body 46, is arranged coaxially with the air inlet 55 of the electric blower 27, and is connected to the air inlet 55 in an airtight manner.

  A circular first exhaust opening 77 having a slightly smaller diameter than the suction port 55 is formed at the center of the rear surface portion 72. The first exhaust opening 77 serves as a main exhaust port of the cover body 46 and communicates with the inside of the inner cylinder portion 66. Further, a plurality of circular second exhaust openings 78 are formed around the first exhaust openings 77 of the rear surface portion 72. These second exhaust openings 78 serve as auxiliary exhaust openings of the cover body 46, have substantially the same diameter as the first exhaust openings 77, and are substantially equally spaced in the circumferential direction of the first exhaust openings 77. They are spaced apart.

  On the other hand, the inner cylindrical portion 66 is a cylindrical inner peripheral surface portion 81 continuous to the rear side of the front surface portion 71 of the outer cylindrical portion 65, and a downstream side surface integrally connected to the rear end portion of the inner peripheral surface portion 81. A certain inner cylinder rear surface portion 82 is integrally provided. A first exhaust air passage 83 is formed around the electric blower 27 in the inner cylinder portion 66.

  The inner peripheral surface portion 81 is spaced apart and opposed to the inner peripheral side of the outer peripheral surface portion 73. Further, on the outer peripheral surface of the inner peripheral surface portion 81, a peripheral wall portion 84 as a first partition wall portion protruding in a flange shape over the entire circumference in the circumferential direction between the inner peripheral side of the outer peripheral surface portion 73, and A plurality of, for example, four side wall portions 85 (FIG. 4) are formed as second linear partition wall portions extending in the axial direction from the peripheral wall portion 84 to the front surface portion 71.

  Further, a circular communication opening 87 is formed at the center of the inner cylinder rear surface portion 82, and the communication opening 87 and the first exhaust opening 77 of the rear surface portion 72 serve as a rear portion of the inner cylinder rear surface portion 82. Are connected in an airtight manner through a cylindrical communication portion 88 formed so as to protrude from the bottom.

  Therefore, between the outer cylindrical portion 65 and the inner cylindrical portion 66, a resonance space 91 is defined between the outer peripheral surface portion 73, the inner peripheral surface portion 81, the peripheral wall portion 84, and the side wall portions 85 and 85, respectively, and A second exhaust air passage 92 is defined between the surface portion 73, the inner peripheral surface portion 81, the peripheral wall portion 84, the inner cylinder rear surface portion 82, the communication portion 88 and the rear surface portion 72.

  On the inner peripheral surface of the inner peripheral surface portion 81, the peripheral edge portion of the fan cover 42 of the electric blower 27 is held via a support rubber 93 as a seal member. The support rubber 93 is formed in a cylindrical shape by a member having elasticity, elastically supports the electric blower 27 with respect to the cover body 46, and includes the opening 75 of the outer cylinder portion 65 and the electric blower 27. The suction port 55 is configured to be airtightly connected.

  The peripheral wall portion 84 is disposed at a position closer to the rear end of the inner cylinder portion 66, that is, on the rear side than the center position of the cover body 46 in the front-rear direction (axial direction). In addition, a plurality of, for example, six circular openings 94 are formed in the peripheral wall portion 84 so as to be spaced from each other at substantially equal intervals in the circumferential direction, and an opening / closing valve 95 as a communication device is provided in each of the openings 94. It is attached.

  The opening 94 communicates each resonance space 91 and the second exhaust air passage 92, and has a lattice-shaped (cross-shaped) rib portion 94a (FIG. 3) formed therein. An open / close valve 95 is attached to the rib portion 94a.

  The on-off valve 95 is located on the rear side of the peripheral wall portion 84, that is, on the second exhaust air passage 92 side, and has a circular plate-like opening / closing portion 95a that opens and closes the opening 94, and an axial shape forward from the center of the opening / closing portion 95a An insertion portion 95b that protrudes in the center of the rib portion 94a and a circular plate-like retaining portion 95c that is formed at the front end portion of the insertion portion 95b and that prevents the on-off valve 95 from coming off are integrated. I have. A coil spring 97 is attached between the retaining portion 95c and the rib portion 94a as an urging means for urging the opening / closing valve 95 forward, that is, in a direction to close the opening 94 by the opening / closing portion 95a. Yes.

  The coil spring 97 has an air pressure difference between each resonance space 91 and the second exhaust air passage 92 (the electric blower chamber 28 (FIG. 5)) or more, that is, the exhaust pressure from the electric blower 27 (FIG. 1). When the exhaust pressure reaches a predetermined exhaust pressure, the opening / closing valve 95 is operated to open the opening 94, and the elasticity is set so that the resonance spaces 91 and the second exhaust air passage 92 are communicated with each other through the opening 94.

  Further, as shown in FIG. 4, the side wall portions 85 are respectively formed on both the left and right width direction upper sides of the inner cylinder portion 66 and on the both sides of the lower side of the inner cylinder portion 66 in the left and right width direction. Therefore, the resonance space 91 is located on the upper side and the lower side with respect to the electric blower 27 and spreads left and right, and the second resonance space 91b located on the left and right sides of the electric blower 27 and spreads up and down. The first resonance space 91a and the second resonance space 91b have different volumes. That is, the volume of the second resonance space 91b is set to be larger than that of the first resonance space 91a. In the present embodiment, for example, the second resonance space 91b has a volume about twice that of the first resonance space 91a. Have.

  Here, as shown in FIGS. 1 and 2, the communication opening 87, together with the communication portion 88, communicates the first exhaust air passage 83 with the electric blower chamber 28 (FIG. 5).

  Further, the resonance spaces 91 communicate with the first exhaust air passages 83 via circular communication openings 99 formed in the inner peripheral surface portion 81 of the inner cylinder portion 66, respectively. The resonance space 91 is formed to have a wide cross-sectional area with respect to the communication opening 99. Here, the cross-sectional area of the resonance space 91 refers to a cross-sectional area in a direction orthogonal to the opening direction of the communication opening 99. Note that the silencing performance in the resonance space 91 is set by the ratio (expansion ratio) between the opening area of the communication opening 99 and the cross-sectional area of the resonance space 91, and the silencing performance increases as this ratio increases. Yes. Further, the frequency of noise that is silenced in the resonance space 91 is set according to the length of the resonance space 91 (the distance from the communication opening 99 to the inner peripheral surface of the outer peripheral surface portion 73).

  The first resonance spaces 91a can communicate with the second exhaust air passage 92 through one opening 94, and the second resonance spaces 91b can communicate with the second exhaust air passage 92 through two openings 94, respectively. It is possible to communicate with. For this reason, the on-off valve 95 is configured to open the opening 94 by reaching different exhaust pressures in the first resonance space 91a and the second resonance space 91b. That is, the on-off valve 95 located in the opening 94 that communicates the first resonance space 91a and the second exhaust air passage 92 has, for example, the first resonance space 91a and the second exhaust air passage 92 (the electric blower chamber 28 (FIG. 5)). ) (The exhaust pressure of the electric blower 27) reaches a predetermined first threshold value TH1, and the on-off valve 95 located at the opening 94 communicating the second resonance space 91b and the second exhaust air passage 92 is For example, a predetermined second threshold TH2 in which the pressure difference (exhaust pressure of the electric blower 27) between the second resonance space 91b and the second exhaust air passage 92 (the electric blower chamber 28 (FIG. 5)) is larger than the first threshold TH1. It is configured to open when it reaches.

  The communication openings 99 are spaced apart from each other at substantially equal intervals in the circumferential direction, and are formed to face the outer peripheral surface of the case body 41 of the electric blower 27 closer to the front side of the case body 48. Therefore, these communication openings 99 are arranged at positions that do not directly face the exhaust port 52 of the electric blower 27, respectively. In other words, the resonance space 91 communicates with the first exhaust air passage 83 at a position that does not face the exhaust port 52 of the electric blower 27.

  The second exhaust air passage 92 communicates in common with all of the resonance spaces 91, and the inner cylinder rear surface portion of the inner cylinder portion 66 from a position closer to the rear side of the outer cylinder portion 65 and the inner cylinder portion 66. It is formed to be bent in an L shape in a cross-sectional view toward the 82 side, and communicates with the electric blower chamber 28 (FIG. 5) via each second exhaust opening 78. Further, the second exhaust air passage 92 is formed to have a wide cross-sectional area with respect to each opening 94. Here, the cross-sectional area of the second exhaust air passage 92 means a cross-sectional area in a direction intersecting (orthogonal) with the passage direction of the exhaust air. In the present embodiment, the sectional area of the second exhaust air passage 92 refers to an area defined by the outer peripheral surface portion 73, the inner peripheral surface portion 81, and the side wall portions 85 and 85 (FIG. 3). In addition, the silencing performance in the second exhaust air passage 92 is set by the ratio (expansion ratio) between the opening area of the opening 94 and the cross-sectional area of the second exhaust air passage 92. The performance is increasing. Further, the frequency of noise that is silenced in the second exhaust air passage 92 is set according to the length of the second exhaust air passage 92.

  Next, the operation of the above embodiment will be described.

  First, as shown in FIG. 5, with the dust collecting part 34 attached in the main body dust collecting chamber 33 of the vacuum cleaner main body 13, as shown in FIG. 6, with respect to the main body suction port 35 of the vacuum cleaner main body 13. After connecting the connecting pipe part 15 of the pipe part 12 and connecting the hose body 16, the extension pipe 18 and the floor brush 19 in order, the floor brush 19 is placed on the floor surface and the gripping part 21 is gripped. By operating the desired setting button 22, the main body control unit causes the electric blower 27 to operate in a desired operation mode such as a weak mode, a medium mode, or a strong mode. Then, the operator causes the floor brush 19 to travel back and forth on the floor surface via the extension pipe 18 by the grip portion 21.

  The negative pressure generated by the driving of the electric blower 27 is the intake opening 62, the suction port 55, the opening 75 shown in FIG. 1, the communication port 31, the dust collecting unit 34, the main body suction port 35 shown in FIG. 5, and the hose shown in FIG. It acts on the floor brush 19 via the body 16 and the extension pipe 18 and sucks dust on the floor surface together with air.

  The sucked air becomes intake air and is sucked into the dust collecting part 34 shown in FIG. 5 from the floor brush 19 through the extension pipe 18, the hose body 16 and the main body suction port 35 together with dust. At 34, dust is collected.

  The intake air that has passed through the dust collecting section 34 is exhausted to the downstream side (outside) of the dust collecting section 34, and is passed through the communication port 31, the inducer 74, and the opening 75 to the suction port 55 of the electric blower 27. The air is sucked in, passes through the case body 41 of the electric blower 27 while cooling the electric motor portion 43 and the like to become exhaust air, and is exhausted from each exhaust port 52 to the outside of the electric blower 27.

  At this time, the operation mode of the electric blower 27 is the weak mode or the middle mode, the input of the electric blower 27 is small (the rotational speed of the centrifugal fan 45 is small), and the exhaust pressure from the electric blower 27 is relatively low ( When the exhaust pressure is less than the first threshold TH1), each opening / closing valve 95 is maintained in a state in which each opening 94 is closed by the biasing force of the coil spring 97 that biases each opening / closing valve 95. Does not communicate with the second exhaust air passage 92. For this reason, the exhaust air from the electric blower 27 passes through the first exhaust air passage 83 as shown by an arrow A1 in FIG. 1, and the electric blower passes through the communication opening 87, the communication portion 88, and the first exhaust opening 77. The air is exhausted to the chamber 28 (FIG. 5) and exhausted from the exhaust hole 37 (FIG. 5) of the main body case 25 to the outside of the cleaner body 13. At this time, each resonance space 91 acts as a resonator of a resonance type (interference type) silencer using Helmholtz resonance, and has a specific frequency peak that is likely to occur when the exhaust pressure from the electric blower 27 is relatively low. Reduce sound.

  On the other hand, when the exhaust pressure from the electric blower 27 is relatively high (the exhaust pressure is equal to or higher than the first threshold TH1), each resonance space 91 and the second exhaust air passage 92 (the electric blower chamber 28 (FIG. 5)) Is increased, and the coil spring 97 that biases each open / close valve 95 contracts against the bias, whereby each open / close valve 95 opens each opening 94. At this time, when the exhaust pressure from the electric blower 27 is not less than the first threshold TH1 and less than the second threshold TH2, only the opening 94 of the first resonance space 91a is opened, and the exhaust pressure from the electric blower 27 is further increased. When the exhaust pressure is high (the exhaust pressure is equal to or higher than the second threshold value TH2), the openings 94 of the second resonance space 91b are also opened. As a result, the exhaust air from the electric blower 27 partially passes through the resonance space 91 and the second exhaust air passage 92 and passes through the second exhaust openings 78 as indicated by arrows A2 and A3 in FIG. The electric blower chamber 28 (FIG. 5) is exhausted, and the remaining other portion passes through the first exhaust air passage 83 and passes through the communication opening 87, the communication portion 88, and the first exhaust opening 77. It is exhausted to FIG. At this time, each resonance space 91 and the second exhaust air passage 92 function as an expansion chamber of an expansion type (expansion type) silencer, and wind noise that is likely to be generated when the exhaust pressure from the electric blower 27 is relatively high. Reduce broadband noise such as.

  The exhaust air exhausted into the electric blower chamber 28 is exhausted from the exhaust hole 37 (FIG. 5) of the main body case 25 to the outside of the cleaner main body 13.

  When cleaning is completed, the operator operates the setting button 22 shown in FIG. 6 to stop the electric blower 27.

  As described above, according to the above-described embodiment, when the exhaust pressure from the electric blower 27 does not reach the predetermined exhaust pressure, each opening 94 is closed by the on-off valve 95, and each resonance space 91 and the second exhaust are closed. Since the air passage 92 does not communicate with each other, the exhaust from the electric blower 27 is exhausted to the electric blower chamber 28 (FIG. 5) via the first exhaust air passage 83 while each resonance space 91 acts as a resonator. Peak noise that is likely to occur when the exhaust pressure is relatively low can be reduced. On the other hand, when the exhaust pressure from the electric blower 27 reaches a predetermined exhaust pressure, each opening 94 is opened by the on-off valve 95 so that each resonance space 91 and the second exhaust air passage 92 communicate with each other. Occurs when the exhaust pressure is relatively high because part of the exhaust from the electric blower 27 is exhausted through each resonance space 91 and the second exhaust air passage 92 while the second exhaust air passage 92 acts as an expansion chamber. Can cope with fluctuations in exhaust pressure without increasing the exhaust loss by increasing the exhaust flow path more than necessary, that is, reducing the suction force by the electric blower 27. Thus, exhaust noise can be reduced.

  That is, by using the resonance space 91 as a resonator and an expansion chamber corresponding to the exhaust pressure from the electric blower 27 and corresponding to the exhaust noise that easily occurs at each exhaust pressure, the exhaust noise can be effectively reduced. .

  Further, by making the cross-sectional area of the second exhaust air passage 92 wider than that of the opening 94, the second exhaust air passage 92 can also be used as an expansion chamber of the expansion silencer. Can be reduced.

  Further, when the on-off valve 95 reaches different exhaust pressures in the first resonance space 91a and the second resonance space 91b, the first resonance space 91a or the second resonance space 91b communicates with the second exhaust air passage 92. Therefore, only the first resonance space 91a can act as an expansion chamber and the second resonance space 91b can act as a resonator, or both the resonance spaces 91a and 91b can act as an expansion chamber. It becomes possible to reduce the exhaust noise of the frequency.

  Specifically, since the volumes of the first resonance space 91a and the second resonance space 91b are different, the first resonance space 91a and the second resonance space are not changed without different configurations of the on-off valves 95 and the coil springs 97. It is possible to easily form a configuration in which 91b communicates with the second exhaust air passage 92 at different exhaust pressures.

  Further, by using the opening / closing valve 95 as the communication device, a configuration for opening and closing the opening 94 according to the exhaust pressure from the electric blower 27 can be easily formed.

  Then, by connecting the resonance space 91 to the first exhaust air passage 83 at a position not facing the exhaust port 52 of the electric blower 27, the exhaust air from the electric blower 27 directly communicates with the resonance space 91. Inflow through 99 can be prevented, and turbulent flow and noise such as wind noise at the communication opening 99 can be prevented.

  In the above embodiment, the on-off valve 95 may be configured to open the opening 94 with different exhaust pressures, for example, by making the elasticity of the coil spring 97 different.

  Further, the communication device is not limited to the configuration using the on-off valve 95.

  Further, a plurality of resonance spaces 91 having substantially the same volume may be arranged, or only one may be arranged.

  And if the 1st exhaust air path 83, the resonance space 91, and the 2nd exhaust air path 92 can be formed in the circumference | surroundings of the electric blower 27, the structure of the cover body 46 will not be limited to said structure.

  The vacuum cleaner 11 is not limited to the canister type, for example, an upright type in which the floor brush 19 is connected to the lower portion of the vacuum cleaner body 13, or a handy device in which the floor brush 19 is connected to the front part of the vacuum cleaner body 13. Even molds can be used correspondingly.

11 Vacuum cleaner
27 Electric blower
28 Electric blower room
52 Exhaust vent
83 First exhaust air passage
91 Resonance space
92 Second exhaust air passage
94 opening
95 Open / close valve as communication device

Claims (6)

An electric blower chamber that houses the electric blower;
A first exhaust air passage that guides exhaust from the electric blower to the electric blower chamber;
A resonant space formed in communication with the first exhaust air passage;
A second exhaust air passage communicating the resonance space with the electric blower chamber side;
An opening communicating the resonance space and the second exhaust air passage;
A vacuum cleaner comprising: a communication device that is disposed in the opening and communicates the resonance space and the second exhaust air passage through the opening by reaching a predetermined exhaust pressure. The vacuum cleaner according to claim 1, wherein the second exhaust air passage has a cross-sectional area larger than that of the opening. A plurality of resonance spaces are provided,
The communication device is disposed between each of the resonance spaces and the second exhaust air passage, and communicates each of the resonance spaces with the second exhaust air passage by reaching different exhaust pressures. The electric vacuum cleaner according to claim 1 or 2, characterized in that. The vacuum cleaner according to claim 3, wherein at least one volume of the resonance space is different from any other remaining volume. The vacuum cleaner according to any one of claims 1 to 4, wherein the communication device is an on-off valve. 6. The electric vacuum cleaner according to claim 1, wherein the resonance space communicates with the first exhaust air passage at a position not facing the exhaust port of the electric blower.

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