CN212318333U

CN212318333U - Blower fan

Info

Publication number: CN212318333U
Application number: CN202020931598.7U
Authority: CN
Inventors: 小出悠贵
Original assignee: Makita Corp
Current assignee: Makita Corp
Priority date: 2019-06-14
Filing date: 2020-05-28
Publication date: 2021-01-08
Anticipated expiration: 2030-05-28
Also published as: JP2020204274A; DE202020001322U1

Abstract

The utility model provides an air blower, the utility model discloses can reduce the noise of air-blower. The blower has: a scroll casing in which a suction port, a scroll chamber, and a discharge port are partitioned; an impeller rotatably supported in the volute; and a motor connected to the impeller and driving the impeller. The scroll casing has: a case main body in which a volute is partitioned; and a bell mouth protruding from the case main body and dividing the suction port. At least a part of the bell mouth is formed of a component independent from the case main body.

Description

Blower fan

Technical Field

The present disclosure relates to a blower that is a kind of work machine.

Background

A blower as a kind of work machine is known. The blower is held or attached in a predetermined posture by a user, and blows air to collect scattered objects such as fallen leaves and cut grass. As such a blower, a hand-held blower and a backpack blower are widely used.

Patent document 1 discloses a backpack blower. The blower includes a volute, an impeller rotatably supported in a volute chamber of the volute, a motor connected to the impeller and driving the impeller, and a casing accommodating a suction port of the volute and the motor. The scroll casing has: a case main body that partitions a volute chamber; and a bell mouth protruding from the case main body and dividing the suction port.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2016 and No. 204930

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

In the conventional blower, a bell mouth is integrally formed with a housing main body in order to simplify the manufacture of the blower. However, since the required thickness of the bell mouth is large relative to the required thickness of the case main body, the parts integrated with them have a non-uniform thickness structure. In order to mold such a component with high precision by using a mold, it is conceivable to provide a so-called material reducing portion (japanese: steal み) in a portion of the bell mouth having a large thickness. However, when the material reducing portion is provided in the bell mouth portion, a plurality of holes or grooves are formed in the surface of the bell mouth, and there is a problem that wind noise is generated due to the plurality of holes or grooves. The present specification provides a technique capable of suppressing such wind noise.

Means for solving the problems

The techniques disclosed herein are embodied as a blower (e.g., a hand-held blower or a backpack blower) held or carried by a user. The blower has: a scroll casing in which a suction port, a scroll chamber, and a discharge port are partitioned; an impeller rotatably supported in the volute; and a motor connected to the impeller and driving the impeller. The scroll casing has: a case main body in which a volute is partitioned; and a bell mouth protruding from the case main body and dividing the suction port. At least a part of the bell mouth is formed of a component independent from the case main body.

In the above-described structure, at least a part of the bell mouth is formed of a component separate from the case main body. This eliminates or suppresses the uneven thickness structure of the components constituting the housing main body, and eliminates the need to provide a material reducing portion on the surface of the bell mouth. Alternatively, the surface of the bell mouth can be made relatively smooth by embedding other components in the material reducing portion (i.e., the hole or the groove) provided in the bell mouth. As a result, wind noise at the bell mouth can be suppressed.

The surface of the bell mouth may be smooth.

The case main body and the bell mouth may be made of a resin material.

The thickness of the bell mouth of the volute may be larger than the thickness of the housing main body of the volute.

The scroll casing may have: a 1 st component part constituting at least a part of the case main body; and a 2 nd component which is assembled to the 1 st component and constitutes at least a part of the bell mouth.

The 2 nd component may be an annular member.

At least one recess may be provided in at least one of the 1 st and 2 nd parts, and the at least one recess may be surrounded by the 1 st and 2 nd parts.

The prime mover may be a motor.

The blower may further include a battery pack that supplies electric power to the motor.

Drawings

Fig. 1 is a perspective view showing an external appearance of a blower 10 according to an embodiment.

Fig. 2 is an exploded perspective view of the blower 10.

Fig. 3 is a sectional view showing the internal structure of the blower 10. The arrows F in the figure schematically indicate the flow of air in the air path 42.

Fig. 4 is a diagram showing an internal structure of the blower 10 with a part of the casing 14 removed. Arrows F in the figure schematically indicate the flow of air in the

air paths

42, 42a, 42 b.

Figure 5 is a cross-sectional view of a volute.

Figure 6 is an exploded perspective view of the volute.

Fig. 7 is a partially exploded perspective view of blower 10, and shows

sound absorbing members

62, 64, 66, and 68.

Description of the reference numerals

2. A battery pack; 10. a blower; 12. a volute pump; 13. a vibration-proof member; 14. a housing; 14a, a base member; 14b, a cover member; 14c, a pipe opening; 14d, bottom; 16. shoulder straps; 18. a battery interface; 18a, a battery terminal; 20. a discharge nozzle; 22. an operating handle; 24. a trigger member; 26. a volute; 26a, a suction inlet; 26b, volute; 26c, a discharge port; 26d, a discharge conduit; 28. an impeller; 30. a motor; 32. a motor controller; 34. a unit holder; 40a, 40b, an external suction port; 42. 42a, 42b, air path; 44. a ground plane; 52. a housing main body; 54. a bell mouth; 56. the 1 st component of the volute; 58. the 2 nd component of the volute; 62. 64, 66, 68, sound absorbing member.

Detailed Description

In one embodiment of the present technology, the surface of the bell mouth may be smooth. With this configuration, wind noise at the bell mouth can be effectively suppressed. However, as another embodiment, the surface of the bell mouth may have irregularities such as small holes or grooves.

In one embodiment of the present technology, the case main body and the bell mouth may be made of a resin material. In such a configuration, the present technology can particularly exhibit its effects.

In an embodiment of the present technology, a thickness of the bell mouth of the volute may be larger than a thickness of the housing main body of the volute. In such a configuration, the present technology can particularly exhibit its effects.

In one embodiment of the present technology, the scroll casing may include: a 1 st component part constituting at least a part of the case main body; and a 2 nd component part assembled to the 1 st component part and constituting at least a part of the bell mouth.

In the above embodiment, the 2 nd component may be an annular member. With this configuration, the suction port of the scroll can be formed with high accuracy.

In the above-described embodiment, at least one of the 1 st and 2 nd members may be provided with at least one recess. In this case, the at least one recess may be surrounded by the 1 st component and the 2 nd component. In other words, at least one material reducing portion may be provided in at least one of the 1 st component and the 2 nd component. In this case, it is preferable that the hole or groove formed by the material reducing portion is located on the joint surface between the 1 st component and the 2 nd component.

Alternatively, the 1 st component part constituting at least a part of the case main body may also constitute a part of the bell mouth. In this case, the 1 st component may have at least one recess provided on a surface of the bell mouth. The 2 nd component may be embedded in the recess of the 1 st component. With this configuration, the surface of the bell mouth can be made relatively smooth, and wind noise at the bell mouth can be suppressed.

In an embodiment of the present technology, the motor may be a motor. The noise of the motor is small compared to the noise of the engine. Therefore, compared to the case where the motor is an engine, the wind noise at the bell mouth is more likely to be emphasized when the motor is a motor. Thus, the present technology can exhibit its effect particularly when the motor is used as the prime mover.

In the above-described embodiment, the blower may further include a battery pack that supplies electric power to the motor. That is, the blower may also be a cordless power tool. However, as another embodiment, the blower may be a wire-type electric tool that supplies electric power through a wire.

Representative, non-limiting examples of the present invention are described in detail below with reference to the accompanying drawings. The detailed description is merely intended to show those skilled in the art the details of preferred examples for carrying out the invention and is not intended to limit the scope of the invention. In addition, in order to provide a further improved pruning machine for gardening, the additional features and technical solutions disclosed below can be used separately or together with other features and technical solutions.

In addition, combinations of features and steps disclosed in the following detailed description are not essential to practice of the present invention in the broadest sense, and are described only for the purpose of describing particular representative examples of the present invention. In addition, in providing additional and useful embodiments of the present invention, it is not necessary that the various features of the above and below described representative examples, as well as the various features of the independent and dependent claims, be combined in the order of description or enumeration with the examples described herein.

All features described in this specification and/or claims, which differ in structure from the features described in the examples and/or claims, are intended to be disclosed separately and independently of each other as a definition of the limits of the application at the outset and as required for the particular circumstances. Further, the description of all the numerical ranges and groups or groups is intended to be completed by disclosing intermediate structures between the first disclosure of the application and the specific matters required.

[ examples ] A method for producing a compound

Referring to the drawings, a blower 10 of an embodiment is illustrated. The blower 10 of the present embodiment is a negative-back type blower, and is one type of work machine mainly used outdoors. The blower 10 is attached to the back of a user in a predetermined posture, and blows air to collect scattered objects such as fallen leaves and grass. The blower 10 is a working machine using the battery packs 2 as a power source, and the two battery packs 2 are configured to be detachable from the blower 10. The number of the battery packs 2 is not limited to two.

As shown in fig. 1 to 4, the blower 10 includes a volute pump 12, a housing 14 that houses the volute pump 12, and a pair of shoulder straps 16. A pair of shoulder straps 16 are secured to the housing 14 to secure the housing 14 to the back of the user. The casing 14 supports the volute pump 12 via a plurality of vibration preventing members 13. The vibration preventing member 13 is a member having elasticity such as a spring or rubber. As an example, the housing 14 of the present embodiment is constituted by a plurality of parts (components) including a base member 14a and a cover member 14 b. The cover member 14b is assembled to the base member 14a, and the base member 14a and the cover member 14b face each other across the volute pump 12.

Two battery ports 18 are provided in the housing 14. One battery pack 2 is detachably mounted to each battery interface 18. Each battery interface 18 is provided with a battery terminal 18 a. The battery terminal 18a is electrically connected to the battery pack 2 mounted on the battery interface 18. The battery terminal 18a includes a pair of power terminals and a plurality of communication terminals. The number of battery interfaces 18 is not limited to two, and blower 10 may have at least one battery interface 18.

The blower 10 has a discharge nozzle 20 connected to the volute pump 12 and an operating handle 22 provided on the discharge nozzle 20. The operation handle 22 is provided with a plurality of switches that are operated by a user, such as a trigger member 24. When the user operates the trigger member 24, the volute pump 12 is supplied with electric power from one or both of the battery packs 2, and the volute pump 12 is started. Thereby, the blower 10 discharges air from the discharge nozzle 20.

The volute pump 12 has a volute 26, an impeller 28 located within the volute 26, and a motor 30 connected to the impeller 28. The volute 26 defines a suction port 26a, a volute chamber 26b, and a discharge port 26 c. The volute 26b extends in a spiral shape between the suction port 26a and the discharge port 26 c. The impeller 28 is fixed to a rotary shaft 30a of the motor 30, and the impeller 28 is rotatably supported in the volute 26 b. The motor 30 receives electric power from the battery pack 2 and drives the impeller 28 to rotate. When the impeller 28 is driven to rotate, the air sucked from the suction port 26a is accelerated in the volute 26b and then discharged from the discharge port 26 c. The discharge nozzle 20 is connected to a discharge port 26c of the scroll casing 26. In the blower 10 of the present embodiment, the motor 30 is located between the user and the scroll casing 26 when the user mounts the blower 10 in a predetermined posture, and the suction port 26a of the scroll casing 26 is opened toward the rear of the user (i.e., the side opposite to the user), but this case is not particularly limited.

Here, the discharge port 26c of the scroll casing 26 is located outside the housing 14. The volute 26 has a discharge duct 26d projecting from the housing 14, with a discharge port 26c at the top end of the discharge duct 26 d. The casing 14 is provided with a duct opening 14c through which the discharge duct 26d passes. As described above, the casing 14 supports the volute pump 12 via the plurality of vibration preventing members 13. Thus, a gap is provided between the discharge duct 26d and the duct opening 14c, thereby permitting relative displacement of the volute 26 with respect to the housing 14.

On the other hand, the majority of the volute pump 12 containing the motor 30 is located within the casing 14. In particular, the suction port 26a of the volute 26 is located within the housing 14, and thus, the housing 14 is provided with

external suction ports

40a, 40 b. The

external suction ports

40a, 40b are one or more openings formed in the housing 14.

Air paths

42, 42a, and 42b extending from the

external suction ports

40a and 40b to the suction port 26a of the scroll casing 26 are defined in the casing 14.

The blower 10 also has a motor controller 32. The motor controller 32 is electrically connected with the battery terminal 18a and the motor 30. Thereby, the discharge power of the battery pack 2 is supplied to the motor 30 via the motor controller 32. The motor controller 32 incorporates one or more power switching elements and controls the power supplied to the motor 30. The motor 30 of the present embodiment is a brushless DC motor, and the motor controller 32 has an inverter circuit built therein. The motor controller 32 faces an air path 42 within the housing 14. This can suppress a temperature rise of the motor controller 32 by the air flowing through the air path 42, but the above is not limited.

The motor controller 32 is assembled to the unit holder 34. The unit holder 34 is positioned inside the housing 14 and assembled to the housing 14. In addition to the motor controller 32, the battery terminal 18a is also assembled to the unit holder 34. According to such a configuration, in the manufacturing process of the blower 10, first, the motor controller 32 and the battery terminal 18a are assembled to the unit holder 34. Next, the unit holder 34 is assembled to the base member 14a of the housing 14 together with the motor controller 32 and the battery terminal 18 a. It is not necessary to separately assemble the motor controller 32 and the battery terminal 18a with respect to the housing 14, and therefore, the assembly of the motor controller 32 and the battery terminal 18a can be easily performed.

The specific structure of the unit holder 34 is not particularly limited. However, in the blower 10 of the present embodiment, the unit holder 34 is assembled across both the base member 14a (part 1) and the cover member 14b (part 2). With this configuration, the rigidity of the housing 14 can be increased by the unit holder 34. In addition, since the cell holder 34 is stably fixed to the case 14, vibration of the motor controller 32 and the battery terminal 18a can be suppressed. This can prevent electrical failure (e.g., contact failure) in the past.

As described above, since the motor 30 is disposed in the housing 14, the noise of the motor 30 can be suppressed from being radiated to the surroundings. However, the

outer suction ports

40a and 40b are formed in the housing 14, and the noise of the motor 30 cannot be prevented from leaking to the outside through the

outer suction ports

40a and 40 b. In this regard, in blower 10 of the present embodiment,

external suction ports

40a, 40b are provided in bottom portion 14d of casing 14. When the user mounts the blower 10 in a predetermined posture, the bottom 14d of the casing 14 faces the floor surface, and the

external suction ports

40a and 40b are opened vertically downward. That is, when the user uses the blower 10, the

external suction ports

40a, 40b of the casing 14 are opened toward the floor. This allows noise leaking from the

external suction ports

40a and 40b to be mainly emitted toward the ground, and can be suppressed from being dispersed to the surroundings.

Here, in the above-described predetermined posture (i.e., the posture in which the blower 10 is mounted on the back of the user), the suction port 26a of the scroll casing 26 opens in the horizontal direction. That is, the direction in which the suction port 26a of the scroll casing 26 opens and the direction in which the

external suction ports

40a, 40b of the housing 14 open are orthogonal to each other. Further, the direction in which the suction port 26a of the scroll casing 26 opens is parallel to the rotation shaft 30a of the motor 30, that is, also parallel to the rotation shaft of the impeller 28.

The positions of the

external suction ports

40a and 40b are not limited to the bottom 14d of the casing 14. However, if the

external suction ports

40a and 40b are located at the bottom 14d of the casing 14, the

external suction ports

40a and 40b are arranged at relatively low positions when the user mounts the blower 10 in a predetermined posture. This can effectively suppress the noise leaking from the

external suction ports

40a and 40b from being radiated to the surroundings. From this viewpoint, the closer the positions of the

external suction ports

40a, 40b are to the bottom 14d of the casing 14, the better. Therefore, the

external suction ports

40a and 40b may be located below the rotation shaft 30a of the motor 30, or may be located further below the scroll casing 26.

In the blower 10 of the present embodiment, the bottom 14d of the housing 14 has a ground surface 44 that contacts the ground when the user places the blower 10 on the ground. The

external suction ports

40a and 40b are provided at positions different from the ground surface 44. If the

external suction ports

40a and 40b are provided on the ground surface 44, the

external suction ports

40a and 40b are completely closed by the ground when the user places the blower 10 on the ground, which may be a problem when the motor 30 continues to rotate by inertia, for example. Thereby, at least a part of the

external suction ports

40a and 40b can be provided at a position different from the ground surface 44.

As shown in fig. 4, in blower 10 of the present embodiment,

external suction ports

40a, 40b have a 1 st external suction port 40a and a 2 nd external suction port 40 b. The

air passages

42, 42a, and 42b include a 1 st air passage 42a extending upward from the 1 st external suction port 40a and a 2 nd air passage 42b extending upward from the 2 nd external suction port 40 b. The 1 st air path 42a and the 2 nd air path 42b are provided along the battery interface 18 and adjacent to the battery pack 2 mounted to the battery interface 18. With this structure, the temperature rise of the assembled battery 2 can be suppressed by the air flowing through the

air paths

42a and 42 b.

Particularly, in the blower 10 of the present embodiment, the battery interface 18 is provided between the 1 st air path 42a and the 2 nd air path 42 b. The 1 st air path 42a is adjacent to the battery pack 2 mounted to one battery interface 18, and the 2 nd air path 42b is adjacent to the battery pack 2 mounted to the other battery interface 18. This can effectively suppress a temperature rise of each battery pack 2.

In the blower 10 of the present embodiment, the amount of air passing through the

external suction ports

40a, 40b of the casing 14 is 95% or more of the amount of air passing through the suction port 26a of the scroll casing 26. In other words, there is substantially no other opening in the casing 14 other than the

external suction ports

40a and 40 b. This prevents noise of the motor 30 from leaking to the outside of the casing 14 from the ground other than the

external suction ports

40a and 40 b.

Next, the structure of the scroll casing 26 will be described with reference to fig. 5 and 6. As shown in fig. 5 and 6, the volute casing 26 has a casing main body 52 that partitions the volute chamber 26b, and a bell mouth 54 that protrudes from the casing main body 52 and partitions the suction port 26 a. The bell mouth 54 has a frustoconical shape with a cross-sectional area increasing from the suction port 26a toward the volute 26 b. The scroll casing 26 is formed of a resin material, and is constructed by combining a plurality of component parts. Each component is manufactured by die forming, but the above is not particularly limited.

In the volute 26, the required thickness of the bell mouth 54 (particularly the end of the bell mouth 54) is large relative to the required thickness of the casing main body 52. Therefore, if the bell mouth 54 is formed integrally with the case main body 52, the parts formed by integrating them have a structure with uneven thickness. In order to mold such a component with high precision by using a mold, it is conceivable to provide a so-called material reducing portion (japanese: steal み) in a portion of the bell mouth 54 having a large thickness. However, when the material reducing portion is provided in the portion of the bell mouth 54, a plurality of holes or grooves are formed in the surface of the bell mouth 54, which causes a problem of wind noise generation.

Regarding the above point, the scroll casing 26 of the present embodiment is constituted by combining a plurality of components. The plurality of components that make up the volute 26 in particular include a 1 st component 56 and a 2 nd component 58. The 1 st component part 56 constitutes at least a part of the case main body 52. The 2 nd component 58 is assembled to the 1 st component 56 and constitutes at least a part of the bell mouth 54. In this way, when at least a part of the bell mouth 54 is formed of a component separate from the case main body 52, the thickness unevenness structure of the 1 st component 56 constituting the case main body 52 can be eliminated or suppressed, and it is possible to eliminate the need to provide a material reducing portion on the surface of the bell mouth 54. This makes it possible to make the surface of the bell mouth 54 (particularly, the surface of the tip portion of the bell mouth 54) relatively smooth.

As an example, in the present embodiment, the 1 st component 56 also forms a part of the bell mouth 54, and the 2 nd component 58 is an annular member and forms the tip end portion of the bell mouth 54. When the 2 nd component 58 is an annular member, the suction port 26a of the scroll casing 26 can be formed with a smooth surface with high accuracy.

In the present embodiment, the 1 st component 56 is provided with a plurality of recesses 56 a. Which is a material reducing portion provided in the 1 st component 56. Similarly, the 2 nd component 58 is also provided with a plurality of recesses 58 a. This is also the material reducing portion provided in the 2 nd component 58. However, these

recesses

56a, 58a are located at the joint surfaces between the 1 st part 56 and the 2 nd part 58. Thus, when the 1 st and 2

nd components

56 and 58 are combined, these

recesses

56a and 58a are located between the 1 st and 2

nd components

56 and 58 and are not exposed to the outside. Therefore, the material reducing portions are provided in the

respective components

56 and 58, but the surface (inner surface) of the bell mouth 54 can be formed smoothly.

As shown in fig. 3, 4, and 7, the blower 10 includes a plurality of

sound absorbing members

62, 64, 66, and 68. A plurality of

sound absorbing members

62, 64, 66, 68 are located inside the enclosure 14. The plurality of

sound absorbing members

62, 64, 66, 68 include a 1 st sound absorbing member 62, a 2 nd sound absorbing member 64, a 3 rd sound absorbing member 66, and a 4 th sound absorbing member 68. Each

sound absorbing member

62, 64, 66, 68 is made of sponge. The sponge referred to herein is a sponge-like (or porous) material in a wide range, and the material constituting the sponge is not particularly limited. The

sound absorbing members

62, 64, 66, 68 can be made of a variety of materials such as resin materials and rubber materials.

The 1 st sound absorbing member 62 is mounted on the inner surface of the cover member 14b of the housing 14 so as to oppose the suction port 26a of the scroll casing 26. The 1 st sound absorbing member 62 is positioned on an extension line of the rotary shaft 30a of the motor 30, and can effectively absorb noise of the motor 30. As described above, the impeller 28 is fixed to the rotating shaft 30a of the motor 30. Therefore, the 1 st sound absorbing member 62 is also located on the extension line of the rotation shaft of the impeller 28. The 1 st sound absorbing member 62 generally has a disc shape.

The 2 nd sound absorbing member 64 is mounted to the inner surface of the base member 14a of the housing 14 between the base member 14a and the motor 30. The 2 nd sound absorbing member 64 is also positioned on the extension line of the rotating shaft 30a of the motor 30, and can effectively absorb the noise of the motor 30. The 2 nd sound absorbing member 64 is also located on the extension line of the rotation shaft of the impeller 28. The 2 nd sound absorbing member 64 faces the 1 st sound absorbing member 62 across the motor 30. By disposing the motor 30 between the two

sound absorbing members

62, 64, the noise of the motor 30 can be effectively absorbed.

The 3 rd sound absorbing member 66 is attached to the base member 14a of the housing 14. The 3 rd sound absorbing member 66 has a cylindrical shape and is disposed so as to surround the motor 30 from a radial direction perpendicular to the rotation shaft 30a of the motor 30. Here, at least a part of the 3 rd sound absorbing member 66 may be formed integrally with the 2 nd sound absorbing member 64. The 3 rd sound absorbing member 66 does not have to have a cylindrical shape, and may have only a plate-like shape and be provided only in a part in the circumferential direction around the motor 30.

The 4 th sound-absorbing member 68 is mounted to the discharge duct 26d of the volute 26 and is provided in a gap between the discharge duct 26d of the volute 26 and the duct opening 14c of the casing 14. As described above, the casing 14 supports the scroll casing 26 via the plurality of vibration preventing members 13. Thus, the volute 26 is displaceable relative to the housing 14, and to allow this displacement, a gap needs to be provided between the discharge duct 26d and the duct opening 14 c. However, when a gap is provided between the discharge duct 26d and the duct opening 14c, there is a possibility that noise of the motor 30 leaks to the outside of the housing 14 through the duct opening 14 c. The 4 th sound absorbing member 68 can suppress such leakage of noise, and can allow relative displacement of the scroll casing 26 since it is made of soft sponge.

Claims

1. A blower is characterized in that a blower body is provided with a blower body,

the blower is a blower held or mounted by a user, and has:

a volute in which a suction port, a volute chamber, and a discharge port are defined;

an impeller rotatably supported within the volute; and

a prime mover connected to the impeller and driving the impeller,

the volute has: a case main body in which the volute is partitioned; and a bell mouth protruding from the case main body and dividing the suction port,

at least a portion of the bell mouth is formed of a component separate from the housing body.

2. The blower according to claim 1,

the surface of the bell mouth is smooth.

3. The blower according to claim 1 or 2,

the case main body and the bell mouth are made of a resin material.

4. The blower according to claim 1,

the thickness of the bell mouth of the volute is greater than the thickness of the housing body of the volute.

5. The blower according to claim 1,

the volute has: a 1 st component part constituting at least a part of the case main body; and a 2 nd component which is assembled to the 1 st component and constitutes at least a part of the bell mouth.

6. The blower according to claim 5,

the 2 nd part is an annular member.

7. The blower according to claim 5 or 6,

at least one recess is provided in at least one of the 1 st and 2 nd parts,

the at least one recess is surrounded by the 1 st and 2 nd parts.

8. The blower according to claim 1,

the prime mover is a motor.

9. The blower according to claim 8,

the blower also has a battery pack that supplies electric power to the motor.