CN214737695U

CN214737695U - Garden blower

Info

Publication number: CN214737695U
Application number: CN202022918612.2U
Authority: CN
Inventors: 喻学锋; 段风伟
Original assignee: Positec Power Tools Suzhou Co Ltd
Current assignee: Positec Power Tools Suzhou Co Ltd
Priority date: 2020-09-29
Filing date: 2020-12-08
Publication date: 2021-11-16
Anticipated expiration: 2030-12-08
Also published as: CN214401586U; CN114319209A; CN114319210A

Abstract

The application relates to a garden blower.A wind inlet shield is connected to an axial wind inlet and comprises a plurality of shield holes for airflow to pass through, and the sum of the ventilation areas of the shield holes defines the effective total ventilation area of the wind inlet shield; an extension bar extending in a longitudinal direction, the operating handle and the air channel portion being pulled apart from each other in the longitudinal direction by means of the extension bar; the linear velocity of the blade edge of the axial flow fan is more than 80m/s, and the effective ventilation total area of the air inlet shield is less than 12000mm². The garden blower lays the pattern of the small air inlet and the thin air duct part (small axial flow fan) by limiting the effective ventilation total area of the air inlet shield. And through the reasonable configuration of parameterization of the motorWhen can reach low-power consumption, can also satisfy the time of endurance of straight-flow battery package, and guarantee wind speed and amount of wind to obtain the efficiency of blowing and the effect of blowing of preferred.

Description

Garden blower

Technical Field

The application relates to the field of electric tools, in particular to a garden blower.

Background

With the increasing of urban greening area, green belts in public places such as parks and roads are spread all over the country, and garden tools are widely used. Garden blowers are a common garden tool that is cleaned by removing dust or debris from the air stream that is blown onto the floor.

Generally, the weight of the garden blower is supported by the user, and when the user holds the machine for cleaning, the height of the machine from foreign objects on the ground, the included angle formed between the machine and the ground, and the left-right swinging blowing amplitude of the machine are all determined by the way that the user holds the machine. Therefore, the volume and the weight of the garden blower are reduced, and the man-machine effect is improved, which is a subject of cumin-free research of researchers and researchers.

SUMMERY OF THE UTILITY MODEL

Based on this, there is a need for a garden blower that is smaller in overall size, lighter in overall weight, and has satisfactory performance.

In order to achieve the above object, the technical solution provided by the present application is as follows:

according to an aspect of the present application, there is provided a garden blower capable of concentrating scattered foreign materials, the garden blower comprising:

the air duct part comprises an axial air inlet communicated with the outside;

a motor for providing driving force for the garden blower;

an axial fan disposed in the air duct portion;

the motor drives the axial flow fan to rotate around the axis of the fan and introduces outside air from the axial air inlet through the air inlet protective cover; the air inlet shield is connected with the axial air inlet and comprises a plurality of shield holes for air flow to pass through, and the sum of the ventilation areas of the shield holes defines the total effective ventilation area of the air inlet shield;

the operating handle is used for being operated and held by a user; and

the battery pack mounting part is used for being detachably connected with a battery pack for supplying power to the motor, and the battery pack mounting part is arranged close to the operating handle;

an extension bar extending in a longitudinal direction, the operation handle and the air channel portion being pulled apart from each other in the longitudinal direction by means of the extension bar;

the linear velocity of the blade edge of the axial flow fan is more than 80m/s, and the effective ventilation total area of the air inlet shield is less than 12000mm²。

The garden blower integrates the rotating speed and the volume of the motor, the diameter of the axial flow fan, the power of the motor and the nominal voltage and the capacity of the battery pack, and is configured, so that the design with small volume, small diameter and light weight can be maximized. Meanwhile, the size of the axial air inlet of the air duct part and the effective ventilation total area of the air inlet shield influence and restrict the air quantity, and the size of the motor and the size of the axial flow fan are also restricted and influenced. When can reach low-power consumption, can also satisfy the time of endurance of direct current battery package, and guarantee wind speed and amount of wind to obtain higher efficiency of blowing and better effect of blowing.

In one embodiment, the air intake shroud is configured to extend longitudinally on a fan axis of the axial fan;

one end of the air inlet protective cover is connected with the axial air inlet, the other end of the air inlet protective cover is supported on the extension rod, the axial flow fan rotates to form a rotating surface, and the projection area of the orthographic projection of the air inlet protective cover which longitudinally falls on the plane of the rotating surface is S1;

the extension rod is connected with one end of the air inlet protective cover and longitudinally falls on the projection area S2 of the orthographic projection of the plane where the rotating surface is located;

wherein 6 is less than or equal to S1/S2 is less than or equal to 16.

In one embodiment, the extension rod has a first end and a second end opposite to each other in the longitudinal direction, the extension rod is connected with the air inlet shield through the first end, and the extension rod is connected with the operating handle through the second end;

the axial fan can rotate to form a rotating surface, the orthographic projection of the first end on the plane of the rotating surface along the longitudinal extension direction of the extension rod is always positioned in the boundary of the outer contour of the rotating surface, and the cross section area of the air inlet protective cover is smaller than 13300mm²。

In one embodiment, the air inlet shield is provided with an insertion part which extends for a preset distance in the extension direction of the extension rod, and the shield holes are circumferentially distributed on the periphery of the insertion part;

the garden blower further comprises a first connecting structure, and the first end of the extension rod is in locking connection with the inserting part of the air inlet shield through the first connecting structure;

along the extension direction of the extension rod, the orthographic projection of the first connecting structure on the plane of the rotating surface and the orthographic projection of the shield hole on the plane of the rotating surface are basically not coincident.

In one embodiment, the insertion portion is configured as a hollow insertion hole, and the first connection structure includes:

the positioning hole is formed in the inner wall of the inserting hole channel; and

the positioning piece is arranged on the extension rod;

the positioning piece is provided with a locking state which is clamped with the inner wall of the positioning hole so as to limit the extension rod from being pulled out backwards from the insertion part.

In an embodiment, in the locked state, an outer profile of the positioning element radially outwardly exceeds an inner wall surface profile of the positioning hole.

In one embodiment, the positioning element further has a natural state of keeping the shape thereof inserted into the insertion part, and in the natural state, the positioning element is at a preset position corresponding to the positioning hole;

and, the positioning member is configured to change its shape in the locked state when subjected to an external force.

In an embodiment, the first connecting structure further includes a stopping portion disposed at the inserting portion, and the stopping portion can abut against the first end of the extension rod to prevent the extension rod from moving forward from the inserting portion.

In an embodiment, the air duct portion includes a main blowing pipe and an auxiliary blowing pipe disposed in communication with the main blowing pipe, the main blowing pipe is provided with the axial air inlet and a main blowing port opposite to the axial air inlet, the auxiliary blowing pipe has an auxiliary air inlet in communication with the main blowing port, a cross-sectional area of the auxiliary air inlet is larger than a cross-sectional area of the main blowing port in a direction perpendicular to the longitudinal direction, and a gap for external air to enter the auxiliary blowing pipe is provided between the main blowing port and the auxiliary air inlet.

In an embodiment, the garden blower is switchable between a first mode of operation in which air is discharged at a relatively high wind speed and a relatively low air volume, and a second mode of operation in which air is discharged at a relatively low wind speed and a relatively high air volume, via the auxiliary barrel;

the auxiliary blowpipe is movably connected with the main blowpipe and can be folded backwards or extended forwards along the longitudinal direction, so that the garden blower can be switched between the first working mode and the second working mode.

In one embodiment, the nominal output voltage of the battery pack is less than or equal to 20V, the capacity of the battery pack is 2 Ah-9 Ah, the maximum rotation speed of the motor is 18000 rpm-35000 rpm, the weight of the garden blower when the battery pack is not connected with the garden blower is not more than 1.5kg, the maximum wind speed of the garden blower in the first working mode is 90-110 mph, and the maximum wind volume of the garden blower in the second working mode is 350-500 cfm; or

The nominal output voltage of the battery pack is more than 20V and less than 56V, the capacity of the battery pack is 2 Ah-9 Ah, the maximum rotating speed of the motor is 20000 rpm-38000 rpm, the weight of the garden blower when the battery pack is not connected with the garden blower is not more than 1.8kg, the maximum wind speed of the garden blower in the first working mode is 110-180 mph, and the maximum wind volume of the garden blower in the second working mode is 420-650 cfm.

In one embodiment, the length of the air channel part is not more than 600 mm.

In one embodiment, the nominal output voltage of the battery pack is less than or equal to 20V, the capacity of the battery pack is 2 Ah-9 Ah, the maximum rotation speed of the motor is 18000 rpm-35000 rpm, the diameter of the motor is less than or equal to 40mm, and the maximum effective ventilation area of the cross section of the axial air inlet perpendicular to the axis of the fan is less than 9000mm²The outer diameter of the axial flow fan is greater than or equal to 50mm and less than or equal to 67 mm; or

The nominal output voltage of the battery pack is more than 20V and less than 56V, the capacity of the battery pack is 2 Ah-9 Ah, the maximum rotating speed of the motor is 20000 rpm-38000 rpm, the diameter of the motor is less than or equal to 45mm, and the maximum effective ventilation area of the cross section of the axial air inlet, which is perpendicular to the axis of the fan, is less than 13000mm²The outer diameter of the axial flow fan is greater than or equal to 50mm and less than or equal to 67 mm.

In one embodiment, a gap is arranged between the outer edge of the blade of the axial flow fan and the inner wall of the air channel part;

the size of the gap in the radial direction is less than 1 mm.

In one embodiment, the linear distance from the highest point of the operating handle to the lowest point of the extension rod is less than 140mm and greater than 40 mm.

According to another aspect of the present application, there is provided a garden blower capable of concentrating scattered foreign materials, the garden blower comprising:

the air duct part comprises an axial air inlet communicated with the outside;

a motor for providing driving force for the garden blower;

the motor drives the axial flow fan to rotate along the axis of the fan and introduces outside air from the axial air inlet;

the motor drives the axial flow fan to rotate along the axis of the fan and introduces outside air from the axial air inlet through the air inlet protective cover;

the operating handle is used for being operated and held by a user; and

an extension bar extending in a longitudinal direction, the operating handle and the air channel portion being pulled apart from each other in the longitudinal direction by the extension bar;

the maximum height of the air inlet shield is H, and the length of the whole machine is L; h: the ratio of L is less than 0.15; the air volume provided by the garden blower is greater than or equal to 350cfm and less than or equal to 650cfm, and the air speed provided by the garden blower is greater than or equal to 70mph and less than 185 mph.

In an embodiment, the maximum width of the intake shroud is W, wherein W: l is less than 0.15.

In one embodiment, the garden blower further comprises a battery pack mounting part for detachably combining with a battery pack for supplying power to the motor, the battery pack mounting part is arranged close to the operating handle;

the number of the battery packs is one, the nominal output voltage of the battery packs is less than or equal to 20V, the maximum rotating speed of the motor is 18000-35000 rpm, the ratio of the maximum height of the air inlet shield to the overall length of the garden blower is 0.09-0.133, the ratio of the maximum width of the air inlet shield to the overall length of the garden blower is 0.09-0.133, the maximum wind speed of the garden blower is 90-110 mph, and the maximum wind volume of the garden blower is 350-500 cfm; or

The number of the battery packs is two, the nominal output voltage of the battery packs is more than 20V and less than 56V, the maximum rotating speed of the motor is 20000 rpm-38000 rpm, the ratio of the maximum height of the air inlet shield to the overall length of the garden blower is 0.11-0.16, the maximum wind speed of the garden blower is 110 mph-160 mph, and the maximum wind volume of the garden blower is 420 cfm-650 cfm.

In one embodiment, the length of the garden blower is 850-1000 mm;

the maximum height of the air inlet shield is greater than 80mm and less than 130 mm; the maximum width of the air inlet shield is larger than 80mm and smaller than 130 mm.

In one embodiment, the length of the air duct part is not more than 600mm, and the overall length of the garden blower is greater than or equal to 850mm and less than or equal to 1000 mm;

the garden blower weighs no more than 1.8 kg.

In one embodiment, the air channel portion comprises a main blowpipe and an auxiliary blowpipe communicated with the main blowpipe, a gap for external air to enter the auxiliary blowpipe can be formed between the main blowpipe and the auxiliary blowpipe, and the garden blower can be switched between a first working mode for discharging air at a relatively high air speed and a relatively low air volume and a second working mode for discharging air at a relatively low air speed and a relatively high air volume through the auxiliary blowpipe;

the ratio of the length of the air duct part in the longitudinal direction to the length of the garden blower in the longitudinal direction is less than or equal to 70%, the weight of the garden blower is not more than 1.8kg, and the maximum rotating speed of the motor is greater than or equal to 18000rpm and less than 40000 rpm.

Drawings

Fig. 1 is a schematic diagram of a prior art garden blower;

fig. 2 is a schematic view of a garden blower according to an embodiment of the present application in a first operating state;

fig. 3 is a schematic view of the garden blower of fig. 2 in a second operating condition;

fig. 4 is a schematic cross-sectional view of a garden blower in a first operating state according to an embodiment of the present application;

fig. 5 is a schematic cross-sectional view of the garden blower of fig. 4 in a second operating condition;

fig. 6 is a schematic view showing the distribution of the center of gravity of the first weight unit, the center of gravity of the second weight unit, and the center of gravity of the whole machine of the garden blower according to the embodiment of the present application;

fig. 7 is a schematic cross-sectional view of the position of the inlet shroud in a first operating state of the garden blower according to an embodiment of the present application;

fig. 8 is a schematic cross-sectional view of the inlet shroud of the garden blower of fig. 7 taken along the line B-B;

fig. 9 is a schematic view illustrating a matching relationship between a positioning member of an extension rod and an air inlet shield when the positioning member is in a locked state according to an embodiment of the present disclosure;

fig. 10 is a schematic structural view of the extension pole shown in fig. 9 when the positioning member of the extension pole is in a natural state;

fig. 11 is a schematic view showing the positions of the center of gravity of the first weight unit, the center of gravity of the second weight unit, and the center of gravity of the whole machine of the garden blower according to another embodiment of the present application;

fig. 12 is a schematic view showing the positions of the center of gravity of the first weight unit, the center of gravity of the second weight unit, and the center of gravity of the whole machine of the garden blower according to still another embodiment of the present application.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, embodiments accompanying the present application are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is capable of embodiments in many different forms than those described herein and that modifications may be made by one skilled in the art without departing from the spirit and scope of the application and it is therefore not intended to be limited to the specific embodiments disclosed below.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In this application, a first feature "on," "over," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or that the first feature is merely at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

A related art hair dryer, as shown in fig. 1, generally includes a main body case 1, a duct, a fan generating an air current, a motor for driving the fan, and a blowing pipe 2 coupled to the main body case. The motor, the duct and the fan are all arranged in the host shell 1, and the blowing pipe 2 is connected with the host shell and is connected with the host shell to form an airflow channel. The blowing pipe is provided with an air outlet 4, the shell is also provided with an air inlet 3, the motor, the fan, the duct and the air outlet 4 are sequentially arranged along the longitudinal direction of the blower, the duct is used for guiding the air flow generated by the fan to move towards the air outlet of the blowing pipe, and the air enters the shell from the air inlet 3 and flows to the air outlet 4 from the air flow channel to be blown out. The host machine shell 1 is also provided with a handle 5 for an operator to hold, and the motor is arranged outside the duct and is positioned below the handle 5.

The main problem with the garden blower described above is that it is contradictory in achieving miniaturization, weight reduction, and high working performance of the machine. In particular, garden blowers encounter mainly cleaning conditions: fallen leaves and small trash on the outdoor home or on the park floor, debris between floor brickwork joints, wet leaves adhering to the floor. The inventor researches and finds that in order to meet the cleaning requirements of the working conditions, the air quantity and the air speed provided by the garden blower are large enough. However, the miniaturization and weight reduction of the functional parts can reduce the working effect of the garden blower, thereby reducing the cleaning ability, and the miniaturization and weight reduction of the battery pack can shorten the operation time of the garden blower. For example, the working effect of the garden blower can be affected and limited while only reducing the volume and weight of the main housing 1, duct and functional parts. Without reducing the bulk of the aforementioned components, reducing the weight by changing the material can affect the strength of the entire device and increase the production costs.

Therefore, the contradiction and the mutual restriction between the miniaturization and the weight reduction and the better working effect are always the pain points of manufacturers.

The inventor of the present application has continued to research and find that the above problems occur in the related art because the structures such as the motor, the fan, the air duct structure, etc. are not reasonably configured and optimized in terms of parameters. For example, there are outstanding problems in that the design is not taken into consideration by combining the structure and size of the fan, the power and rotation speed of the motor, and the structure of the air duct with the blowing performance and power consumption, resulting in small wind speed and wind volume of the whole machine, low blowing efficiency, and difficulty in blowing up heavy leaves falling on lawns and leaves in crevices, for example. Or, the blowing efficiency of the whole machine with large volume and mass is guaranteed but the noise is large and the power consumption is too high, when the battery pack is used for supplying energy, the working time of the blower can be kept short, and the human-computer experience is poor.

Therefore, there is a need for a garden blower that is smaller in overall size, lighter in overall weight, and capable of meeting the requirements.

Figure 2 shows a schematic view of the garden blower in a first operating state according to an embodiment of the present application; fig. 3 shows a schematic view of the garden blower of fig. 2 in a second operating state. For convenience of explanation, only portions related to the embodiments of the present application are shown.

The garden blower 100 of the embodiment of the present application, which is used to perform a cleaning operation, can collect scattered foreign matters, such as leaves or garbage. For convenience of understanding, the direction of the air flow flowing out corresponding to the air outlet is defined as the front (far end) as shown in fig. 2 and 3, for example, the far end of the garden blower 100 refers to the end of the user away from the user when the garden blower is used for sweeping. Accordingly, the side into which the air flows is defined as the rear (proximal end), for example, the proximal end of the garden blower 100 refers to the end of the garden blower 100 that is closer to the user when the user is using the garden machine for sweeping. Garden blower 100 extends longitudinally between a proximal end (rearward) and a distal end (forward) generally in the direction of arrow a. The upper side of the drawing is defined as the upper side, and the lower side of the drawing is defined as the lower side. As shown in fig. 2, the drawing sheet is defined outward as the left side and the drawing sheet is defined inward as the right side; as shown in FIG. 3, the drawing sheet is defined inward as the left side and the drawing sheet is defined outward as the right side. The height of the garden blower refers to the size of the garden blower in the up-down direction, and the width of the garden blower refers to the size of the garden blower in the left-right direction. It is to be understood that the above definitions are for illustration purposes only and are not to be construed as limitations of the present application.

Garden blower 100, in at least one embodiment disclosed herein, includes a housing, a motor 40, a fan, and a power source.

Referring to fig. 2 to 3, the housing includes a duct portion 10 extending substantially in a longitudinal direction, an operating handle 30 to be held by a user, and an extension rod 20 extending in the longitudinal direction for a predetermined distance. The operating handle 30 and the air channel portion 10 are pulled away from each other in the longitudinal direction by the extension pole 20. Specifically, in some embodiments, the air channel portion 10 includes an axial air inlet 12 (see fig. 4 and 5) communicating with the outside, the extension rod 20 is configured as a tubular structure extending longitudinally between the proximal end and the distal end thereof, and the extension rod 20 includes a handle support section connected to the operating handle 30 at the rear side, an air channel support section connected to the air channel portion 10 at the front side, and an intermediate section connecting the handle support section and the air channel support section. The axial air inlet 12 of the air channel portion 10 and the operating handle 30 are pulled away from each other in the longitudinal direction by the middle section of the extension rod 20.

The operating handle 30 is used for a user to operate and hold, and has the holding portion 32 for the operator to hold, and the operating handle 30 may be provided independently or integrally formed with the extension pole 20. For example, in some embodiments, the operating handle 30 may be configured to be independently supported at the proximal end of the elongate rod 20; in other embodiments, at least a portion of the proximal end of the elongate shaft 20 may form the operating handle 30. Further, the air channel portion 10 extends lengthwise along a first axis (not shown), and the holding portion 32 extends lengthwise along a second axis (not shown). The first axis and the second axis define a first plane (the vertical plane in fig. 2 and 3) that is perpendicular to a second plane (the horizontal plane in fig. 2 and 3) that is parallel to the second axis. The projection of the operating handle 30 on the second plane is longitudinally spaced apart from the projection of the air duct portion 10 on the second plane by a predetermined distance. In some embodiments, the first axis and the second axis are disposed at an angle, such that when the grip portion 32 is held for blowing operation, the second axis of the grip portion 32 is generally parallel to a horizontal plane, which is very comfortable to operate and avoids fatigue during long-term operation. Of course, in other embodiments, the first axis may be parallel to the second axis, which may be advantageous to reduce the size and volume of garden blower 100. In addition, the operating handle 30 is further provided with a control switch 34 (see fig. 4 and 5), the control switch 34 is electrically connected to the motor 40 to control the on and off of the motor 40, and indeed, the control switch 34 can also control the rotation speed of the motor 40.

Fig. 4 shows a schematic cross-sectional view of a garden blower in an embodiment of the present application in a first operating state; fig. 5 shows a schematic cross-sectional view of the garden blower of fig. 4 in a second operating state.

Referring to fig. 4 and 5, the air duct portion 10 is configured as a tubular body with a hollow interior, and two opposite ends of the air duct portion 10 are respectively provided with an axial air inlet 12 and an axial air outlet (not labeled), it can be understood that the hollow is that air can smoothly flow between the axial air inlet 12 and the axial air outlet. The air channel portion 10 includes main blowing pipes 11 extending substantially in the longitudinal direction, and the number of the main blowing pipes 11 may be one and only one; of course, the main blowpipe 11 may be a blowpipe having a complete blowing function formed by combining two or more pipe bodies. The main blowing pipe 11 is located at the distal end of the extension pole 20, so that the entire length of the air channel portion 23 can be shortened, the flow resistance of the air flow in the air channel portion 10 is reduced, and the entire machine can have a smaller volume.

The fan is arranged in the air duct portion 10, and the motor 40 is connected with the fan and used for driving the fan to rotate, so that the fan rotates around a fan axis, and air entering from the axial air inlet 12 side is driven to form an air flow flowing towards the axial air outlet side, so as to provide driving force for the garden blower. Specifically, the fan is an axial flow fan 50, the axial flow fan 50 may provide a better blowing effect than a centrifugal fan, the axial flow fan 50 may be made of a fiber composite material structure or an aluminum metal structure or a magnesium metal structure, a fan axis of the axial flow fan 50 coincides with a center line of the air channel portion 10, and blades of the axial flow fan 50 rotate to form a rotation plane, the rotation plane is disposed perpendicular to the fan axis of the axial flow fan 50 and the center line of the air channel portion 10, so that the airflow is facilitated to flow rapidly. In particular, in the embodiment, the air channel portion 10 includes an upstream region from the axial intake port 12 to the axial fan 50, and a downstream region from the axial fan 50 to the axial outtake port, and the length of the upstream region is smaller than that of the downstream region. The motor 40 is disposed in an upstream region of the air duct portion 10, and is longitudinally offset from the axial air inlet 12. The motor 40 has a motor shaft connected to the axial flow fan 50 and can drive the axial flow fan 50 to rotate about its fan axis, thereby moving air from the upstream area to the downstream area of the air channel portion 10 to form an air flow. Of course, in other embodiments, the motor shaft may be connected to the axial fan 50 through a transmission mechanism, which is not limited herein, for example, the transmission mechanism may be a planetary gear mechanism.

As a specific embodiment, the axial flow fan 50 includes a hub 52 coupled to the motor shaft and a plurality of blades 54 mounted on the hub 52, and a gap is provided between the outer edge of the blade 54 and the inner wall of the air channel portion 10 to avoid the blade from interfering with the inner wall of the air channel portion 10 and form a high-pressure and high-speed air flow, and preferably, the size of the gap in the radial direction is less than 1 mm. Further, the axial fan 50 further comprises a circumferential connecting band, the circumferential connecting band is connected with all the blades 54 in a surrounding manner, and the circumferential connecting band is arranged, so that on one hand, the rigidity of the axial fan 50 can be increased, the service life of the axial fan 50 is prolonged, and the phenomena that the axial fan 50 is damaged after being used for a period of time and the like are prevented; on the other hand, the stability of the axial flow fan 50 after high-speed rotation can be increased, which is helpful for reducing the noise generated after the axial flow fan 50 rotates at high speed.

The power source is used to power the motor 40 and may be a dc power source, and specifically may be a rechargeable battery pack 60, with the battery pack 60 being removably mounted to the housing. Specifically, the housing is provided with one or two or more battery pack mounting portions for the battery pack 60 to be combined, the battery pack mounting portions are disposed near the operating handle 30, and the number of the battery packs 60 matches the number of the battery pack mounting portions. It should be understood that the battery pack mounting portion should be disposed close to the operating handle 30, so that the weight unit can be made as close as possible to the operating grip point, reducing the fatigue of the user's work. In particular, in some embodiments, the battery pack mounting portion is mounted on or integrally formed with the proximal end of the elongate member 20 or near the operating handle 30. When the battery pack 60 is connected to the battery pack mounting portion, the foremost end edge of the operating handle 30 is located between the rearmost end edge of the battery pack 60 and the axial air inlet 12 in the longitudinal direction, and the foremost end edge of the operating handle 30 and the rearmost end edge of the axial air inlet 12 are spaced by a predetermined distance in the longitudinal direction. In this way, the battery pack 60 located at the rear can balance the position of the center of gravity of the garden blower 100 in the longitudinal direction (the center of gravity here is understood to be the center of gravity of the whole machine in the state where the battery pack 60 is attached) in the state where the battery pack 60 is attached to the battery pack attaching portion. Specifically, in the embodiment shown in fig. 6, the nominal voltage of the single battery pack 60 is 20V, G' is the center of gravity of the garden blower as a whole, J is the center of gravity of the first weight unit (the battery pack 60 and the handle 30), and M is the position of the center of gravity of the second weight unit (the movement) of the garden blower. Thus, the center of gravity of the garden blower 100 is balanced in the longitudinal direction, so that the center of gravity of the whole machine is closest to the holding part 32 as much as possible, and the working fatigue of a user is reduced.

More specifically, as shown in fig. 2 and 3, the battery pack 60 may be at least partially disposed below the operating handle 30, or may be disposed behind the grip portion 32. The insertion direction of the battery pack 60 may be set at an angle to the extending direction of the axis of the extension rod 20 and the air channel portion 10. Preferably, the angle may be 30 to 60 degrees, and more preferably, the angle may be 45 degrees. The number of the battery packs 60 can be one, two or more, and the garden air outlet machine can select different types and numbers of the battery packs 60 according to specific design.

The battery pack 60 of the embodiment of the present application can supply power to at least two different types of dc tools, and can be used in general for garden blowers 100, lawn mowers, chain saws, pruners, angle grinders, electric hammers, electric drills, and other electric tools, for example. Thus, the user can only purchase the bare machine of the garden blower 100 and supply power to the garden blower 100 by using the battery pack 60 on the existing other electric tool, so that the energy sharing of multiple tools is realized, and on one hand, the universal use of the battery pack 60 platform is facilitated; on the other hand, the purchase cost is saved for the user. Specifically, in some embodiments, the battery pack 60 may be fixed to the battery pack mounting portion by a snap-fit method or a plug-in method, for example, in some embodiments, the battery pack 60 includes sliding rail portions (not numbered) disposed on two sides thereof, and a snap-fit portion and a plurality of electrode connecting pieces (not shown) disposed on an upper side thereof. The slide rail part can be matched and connected with the battery pack mounting part to realize that the battery pack 60 is limited in the radial direction, and the buckling part is in buckling connection with the shell to realize that the battery pack 60 is limited in the axial direction, so that the battery pack 60 is stably connected to the battery pack mounting part.

Referring to fig. 4 and 5, garden blower 100 further includes a flow guide structure 80 disposed in air channel portion 10, and flow guide structure 80 is located downstream of axial fan 50 to guide the movement of air flow. Specifically, the flow directing structure 80 includes a flow cone 82, an outer shroud 84 housing the flow cone 82, and stationary vanes 86 positioned between the flow cone 82 and the outer shroud 84. The deflector cone 82 is disposed generally along the direction of movement of the airflow, the deflector cone 82 is located at the center of the airflow path, and the deflector cone 82 includes a housing and a conical cavity disposed within the housing. The flow cone 82 has an outer shell and an outer cover 84 defining a flow passage space therebetween, the flow passage space having a generally annular cross-section taken perpendicular to the longitudinal axis. The vanes 54 are located within the annular flow-through space and are generally spaced apart. The spacing between each pair of stationary vanes 54 provides airflow communication. In the embodiment, the stationary blades 54 are inclined at an angle of preferably 5 to 15 degrees with respect to the moving direction of the airflow, and the stationary blades 54 fixedly connect at least one of the guide cone 82 and the outer shroud 84 in the radial direction. In a preferred embodiment, the radial dimension of the guiding cone 82 is smaller than the radial dimension of the motor 40, accordingly, the volume of the guiding cone 82 is smaller than the volume of the motor 40, and the housing 84 is accommodated in the air channel portion 10 and is fixedly connected to the air channel portion 10.

The garden blower 100 further comprises an air inlet shield 70, the air inlet shield 70 is connected to the axial air inlet 12 of the air channel portion 10, the motor 40 can drive the axial fan 50 to rotate around the fan axis to introduce external air from the axial air inlet 12 through the air inlet shield 70, and an air flow channel for air flowing is formed between the air inlet shield 70 and the axial air outlet. Wherein, to facilitate cleaning the air duct portion 10, the air inlet shield 70 and the axial air inlet 12 may be configured to be detachably connected. Specifically, the intake shroud 70 is configured to extend in the fan axial direction of the axial flow fan 50, and one end of the intake shroud 70 is connected to the axial intake port 12 and the other end is supported on the extension rod 20. It will be appreciated that the air intake shroud 70 serves to prevent a user's fingers from penetrating into the interior of the air channel portion 10, thereby causing a hazard, and serves to prevent, for example, leaves or foreign matter from entering the air channel portion 10 during a cleaning operation, thereby causing the motor 40 and the axial flow fan 50 to malfunction. Specifically, in some embodiments, the air inlet shield 70 includes a plurality of shield holes 74 (see fig. 8) for passing the air flow, the air enters the axial air inlet 12 of the air duct portion through the plurality of shield holes 74, and the sum of the ventilation areas of the plurality of shield holes 74 defines the total effective ventilation area of the air inlet shield. That is, the effective ventilation total area of the intake shroud can be understood as the sum of the cross-sectional areas of the intake shroud 70 in the direction perpendicular to the longitudinal direction through which the airflow can flow. In addition, the air inlet cover 70 is not plane, for example, as shown in the embodiment shown in fig. 4 and 5, the air inlet cover 70 forms an arc-shaped air inlet surface extending along the longitudinal direction. In one embodiment, the maximum diameter of the shield holes 74 is not greater than 7mm, and preferably, the maximum diameter of the shield holes 74 is not greater than 4 mm. Therefore, the axial air inlet 12 can prevent sundries from entering while protecting the human body.

It should be emphasized that, in the embodiment of the present application, the motor 40, the axial fan 50, and the guiding structure 80 are disposed in the air duct portion 10, and are longitudinally separated from the operating handle 30 for holding, so on one hand, under the premise that the garden blower 100 has a certain length, the length of the air duct portion 10 is shortened, when the motor 40 drives the axial fan 50 to rotate at a high speed, the external air can be quickly and sufficiently introduced into the air duct portion 10, the air flows in quickly, the air flow loss is small, and the sufficient amount of air flow is quickly driven by the motor 40, and the air pressure is large. Reducing the radial dimension of the tunnel portion 10 optimizes the performance and volume of the garden blower 100, which in turn reduces the weight of the garden blower 100. On the other hand, the distance between the air duct portion 10 containing the movement and the operating handle 30 is reduced, the height of the garden blower 100 is also reduced, and the volume and the weight of the whole machine are both reduced.

It will be appreciated that the performance of garden blower 100 is primarily determined by the product's air volume and velocity, which are primarily determined by the blowing effect of axial fan 50 and the configuration of the air path. The blowing effect of the axial fan 50 is mainly determined by the air volume and the air pressure of the axial fan 50, and taking the axial fan 50 as an example, the air volume of the axial fan 50 is denoted by a symbol Q_{Wind power}Expressed, it is mainly expressed by the following formula: q_{Wind power}＝Q’×π/4×D²X V; wherein, Q': a flow coefficient, related to the form of the blower axial fan 50; d: the outer diameter of the axial fan 50; v: the peripheral speed (linear speed of blade edge) of the outer periphery of the axial fan 50. Therefore, in the same form of the axial flow fan 50 (i.e., Q' is constant), and the air volume of the axial flow fan 50 is kept constant, the linear velocity V of the blade edge of the axial flow fan 50 is inversely proportional to the diameter D of the axial flow fan.

The wind pressure of the axial flow fan 50 is a difference between the total pressure of the air flow on the air outlet side and the total pressure of the air flow on the air inlet side of the axial flow fan 50, and is referred to as a wind pressure, which is denoted by a symbol H. Is mainly expressed by the following formula: h ═ ρ × H × D²×N²(ii) a ρ: the density of the air; h: pressure coefficient, generally related to the form of the axial fan 50; d: the outer diameter of the axial fan 50; n: the rotational speed of the axial fan 50. Therefore, in the same form of the axial flow fan 50, the rotational speed of the axial flow fan 50 and the diameter of the axial flow fan 50 are substantially equal to each other while maintaining the same wind pressureIn an inverse relationship.

The inventor of the present application has analyzed that if the rotation speed of the motor 40 and the blade angle are set to be constant, the larger the diameter of the axial fan 50 is, the higher the air volume and the wind speed can be obtained under the same air duct structure, but the power consumption of the hair dryer is higher, and the working time of the hair dryer is limited when the battery pack 60 is used as a power source. Therefore, to reduce the power consumption of the blower, the diameter of axial fan 50 tends to decrease, and as the diameter of axial fan 50 decreases, the power consumption of garden blower 100 gradually decreases, with the result that the air volume and air speed of the blower generally tend to decrease. Therefore, when considering the power consumption, the blowing effect of the hair dryer is considered, the diameter of the axial fan 50, the rotating speed of the motor 40 and the air channel structure need to be reasonably configured, that is, reasonable parameter configuration is expected, so that the wind speed and the wind volume can meet the performance requirements, but the power consumption is within a controllable range, and compared with the garden hair dryer 100 in the prior art, the volume and the quality are reduced. Meanwhile, in the same form of the axial flow fan 50, the rotational speed of the axial flow fan 50 is in an approximately inverse relationship with the diameter D of the axial flow fan 50 while maintaining the same wind pressure, that is, while maintaining a desired wind volume and wind pressure, the rotational speed of the axial flow fan 50 needs to be increased by reducing the diameter of the axial flow fan 50, and the rotational speed of the axial flow fan 50 is mainly determined by the motor 40, so that the diameter of the axial flow fan 50 can theoretically be decreased by using the motor 40 having a higher rotational speed in order to maximize the design of small volume, small diameter, and light weight. Therefore, the motor 40 with high output power, small volume, small diameter and high rotation speed can realize the light weight of the garden blower 100, the size of the axial flow fan 50 driven by the motor 40 can be obviously reduced, the weight of the axial flow fan 50 is also reduced, and the corresponding air channel part 10 surrounding the axial flow fan 50 can be designed to be smaller than the size and the weight of the existing garden blower 100 on the market. However, the consequence of this is that a higher rotational speed of the motor 40 means a higher maximum output power of the motor 40, and the nominal voltage and capacity of the battery pack 60 must be taken into account to ensure that the garden blower 100 is operational.

Based on the above analysis, the blade angle is set to be constant, and the linear velocity V of the blade edge of the axial fan 50 is positively correlated with the rotational speed V of the axial fan 50 and the diameter D of the axial fan 50. In the embodiment of the application, the linear speed of the blade edge of the axial flow fan is limited to be more than 80m/s, and the effective ventilation total area of the air inlet shield is limited to be less than 12000mm². Preferably, the linear velocity of the blade edge of the axial flow fan is more than 83m/s, and the effective ventilation area of the air inlet shield is less than 9000mm²。

In this way, the rotation speed and volume of the motor 40, the diameter of the axial flow fan 50, and the power of the motor 40 are integrally considered and configured with the nominal voltage and capacity of the battery pack 60, so that the design of small volume, small diameter, and light weight can be maximized. Meanwhile, the size of the axial air inlet 12 of the air duct portion 10 and the total effective ventilation area of the air inlet shield 70 affect and restrict the air volume, and also restrict and affect the size of the motor 40 and the size of the axial fan 50, and the layout of the "small" air inlet and the "thin" air duct portion is also established by limiting the total effective ventilation area of the air inlet shield. When can reach low-power consumption, can also satisfy the time of endurance of direct current battery package 60, and guarantee wind speed and amount of wind to obtain higher efficiency of blowing and better effect of blowing.

In the embodiment, the motor 40, the axial flow fan 50 and the flow guiding structure 80 of the garden blower 100 are all disposed in the air channel portion 10, and the motor 40 is disposed in the upstream area between the axial air inlet 12 of the air channel portion 10 and the axial flow fan 50. In order to make the motor 40 have high rotation speed and small volume, the diameter of the motor 40 is not higher than 45mm, usually 36 mm-45 mm, and a certain gap is required to be kept between the motor 40 and the inner wall of the air duct portion 10 to provide sufficient air intake.

For example, the motor 40 may adopt an outer rotor brushless motor 40, which can achieve high rotation speed while having a small diameter and volume. The maximum rotation speed of the outer rotor brushless motor 40 is configured to be greater than 18000rpm and less than 40000rpm, for example, the maximum rotation speed of the motor 40 may be 18000rpm, 25000rpm, 27000rpm, 29000rpm, 32000rpm, 35000rpm, 38000 rpm. The motor 40 has a diameter not higher than 45 mm. Preferably, the thickness can be set between 36-45 mm. Therefore, the diameter of the motor 40 may be set to 36mm, 37mm, 38mm, 39mm, 40mm, 41mm, 42mm, 43mm, 44 mm.

Further, as a preferred embodiment, the ratio of the cross-sectional area of the motor 40 in the vertical longitudinal direction to the cross-sectional area of the axial air inlet 12 of the air channel portion 10 is less than 0.5. The diameter of the axial inlet 12 of the air duct portion 10 is greater than 50mm and less than 130mm, for example, the diameter of the axial inlet 12 of the air duct portion 10 may be 50mm, 55mm, 65mm, 70mm, 80mm, 85mm, 93mm, 100mm, 110mm, 120 mm.

Further, since the motor 40 is located in the upstream area of the air duct portion 10, the motor 40 occupies a certain space and volume, air moves along the air duct portion 10, and the upstream area of the air duct portion 10 includes a plurality of air passing surfaces. The air passing surface is a cross section of the upstream area of the air channel part 10 perpendicular to the moving direction of the airflow. In order to ensure sufficient air intake, the area of the smallest air passing surface in the upstream region is larger than the area of the rotating surface formed by the rotation of the blades 54 of the axial flow fan 50, so that continuous air supplement contact with the blades 54 of the axial flow fan 50 can be ensured, and the uninterrupted air blowing can be ensured. Similar to the cask theory, the amount of air that the upstream zone supplements the axial fan 50 is dependent upon the minimum overfire area in the upstream zone. Therefore, even if the air passing area is larger in the other part of the upstream area, the air intake amount of the axial flow fan 50 will not change if the smallest air passing area is unchanged. Therefore, the air intake of the axial flow fan 50 can be increased by increasing the minimum air passing area of the entire upstream area. As shown in fig. 4 and 5, after the air enters the upstream region from the axial inlet 12, since the portion of the upstream region close to the axial inlet 12 is not blocked, the air passing area of the portion can be ensured to be larger than the rotation area of the axial fan 50. The portion of the upstream region surrounding the motor 40 is defined as a surrounding region, and due to the blockage of the motor 40, the area of the surrounding region that is over-wind is relatively small. However, in order to ensure good blowing efficiency, the minimum area of the air passing areas of the surrounding areas in the longitudinal direction is designed to be larger than the area of the rotational plane formed by the rotation of the blades 54 of the axial flow fan 50.

In order to take into account the rotational speed of the motor 40 and the power consumption of the hair dryer, in some embodiments of the present application, the output power of the motor 40 is set to be different for different power sources. For example, the nominal output voltage of the battery pack 60 is less than or equal to 20V, and the maximum output power of the motor 40 is 280-400W; the nominal output voltage of the battery pack 60 is more than 20V and less than 56V, and the maximum output power of the motor 40 is 500-1100W. Thus, not only the power and the rotating speed of the motor 40 are considered, but also the power consumption of the hair dryer and the nominal voltage and capacity of the battery pack 60 are considered, and the working time and the working efficiency of the garden hair dryer 100 are ensured. In the maximum output power range, the weight of the motor 40 is in the range of 0.1-0.3 kg. Therefore, the weight of the motor 40 may be set to 0.15kg, 0.25kg, 0.26kg, 0.27kg, 0.28kg, 0.29 kg.

Further, for different types and numbers of battery packs 60, in order to achieve better blowing performance and blowing efficiency, and further maximize the effect of the high rotation speed plus the movement of the small axial flow fan 50, the inventors of the present application have found that the rotation speed and the diameter of the motor 40, the cross-sectional area of the axial air inlet 12, and the diameter of the axial flow fan 50 can be further optimized and parameterized. In some embodiments, the nominal output voltage of the battery pack 60 is less than or equal to 20V, the capacity of the battery pack is between 2Ah and 9Ah, the maximum rotation speed of the motor 40 is between 18000rpm and 35000rpm, the diameter of the motor 40 is less than or equal to 40mm, the operating time of the battery pack is not less than 6min, the effective ventilation area of the axial air inlet 12 is less than 9000mm²The outer diameter of the axial flow fan 50 is 50mm or more and 67mm or less. Therefore, the effective ventilation area of the axial air inlet 12 can be 8500mm²、7500mm²、7000mm²And the like.

In a preferred embodiment, the nominal output voltage of the battery pack 60 is less than or equal to 20V, the capacity of the battery pack is between 2Ah and 9Ah, the maximum rotation speed of the motor 40 is 27000rpm, the working time of the battery pack is greater than or equal to 8min, the diameter of the motor 40 is less than or equal to 40mm, the diameter of the axial air inlet 12 is 80mm to 100mm, and the effective ventilation area of the axial air inlet is less than 6500mm²The diameter of the axial flow fan 50 is 59 mm.

In other embodiments, when the nominal output voltage of the battery pack 60 is greater than 20V and less than 56V, the capacity of the battery pack 60 is 2Ah to 9Ah, the maximum rotation speed of the motor 40 is 20000 to 38000rpm, the working time of the battery pack is not less than 6min, the diameter of the motor 40 is not greater than 45mm, and the effective ventilation area of the axial air inlet 12 is less than 13000mm²The outer diameter of the axial flow fan 50 is 50mm or more and 67mm or less. Therefore, the effective ventilation area of the axial air inlet 12 can be 9200mm²、9800mm²、 11000mm²And the like. As a preferred embodiment, the nominal output voltage of the battery pack 60 is more than 20V and less than 56V, the capacity of the battery pack 60 is 2 Ah-9 Ah, the maximum rotation speed of the motor 40 is 32000rpm, the diameter of the motor 40 is less than or equal to 45mm, the diameter of the axial air inlet 12 is 100 mm-120 mm, the working time of the battery pack is more than or equal to 10min, and the effective ventilation area of the axial air inlet is less than 8000mm²The axial flow fan 50 has a diameter of 60 mm.

Thus, under the layout of forming the high-speed motor 40 and the small axial flow fan 50, the motor 40, the axial flow fan 50 and the air duct portion 10 of the garden blower 100 are smaller in size, so that compared with the prior art, the garden blower 100 is smaller in size, lighter in weight and higher in use experience.

In some embodiments of the present application, the extension pole 20 has a first end and a second end longitudinally opposite to each other, which may be opposite ends in the longitudinal extension direction of the extension pole 20. Wherein the first end may be a distal end of the elongate rod 20 and the second end may be a proximal end of the elongate rod 20. The extension rod 20 can be connected to the intake shroud 70 through a first end and to the operating handle 30 through a second end. When the extension rod 20 is connected to the air inlet shroud 70 through the first end, the orthographic projection of the first end falling on the rotating plane formed by the rotation of the axial flow fan along the longitudinal extension direction of the extension rod 20 is always located within the outer contour boundary of the rotating plane of the axial flow fan 50. It can be understood that, because the axial fan 50 is installed in the air channel portion 10, the extension rod 20 and the air channel portion 10 will not be overlapped in radial direction, and the garden blower has regular shape and compact structure.

Illustratively, the gripping portion 32 of the operating handle 30 extends lengthwise along a second axis, and the extension pole 20 and the air channel portion 10 extend lengthwise along a first axis, which is parallel to the second axis. Therefore, the distance between the highest point of the operating handle 30 and the lowest point of the extension pole 20, i.e., the distance between the upper side of the grip portion 32 and the lower side of the extension pole 20, may be more than 40mm and less than 140 mm. As a preferred embodiment, the linear distance is greater than 128mm, less than 135 mm; more preferably, the straight distance from the highest point of the operating handle 30 to the lowest point of the extension pole 20 is 130 mm. The distance between the highest point and the lowest point of the garden blower 100 connected to the battery pack 60 may be 150mm to 170mm, preferably 159mm, while the distance between the highest point and the lowest point of the conventional garden blower connected to the battery pack 60, as shown in fig. 1, may reach 260 mm to 270 mm.

It should be understood that the extension rod 20 is connected within the boundary of the outer contour of the intake shroud 70, and inevitably occupies a portion of the intake area of the intake shroud 70. The intake air amount of the intake air shield 70 is influenced to some extent. The cross-sectional area of the air inlet channel formed between the air inlet cover 70 and the extension rod 20 in the radial direction should be within a reasonable range to ensure the air inlet volume of the garden blower, and at the same time, the air flow can stably enter and flow through the fan area to form a high-speed and high-pressure air flow, thereby effectively ensuring the performance of the garden blower. In some embodiments, the air intake shroud 70 is configured to extend on the fan axis of the axial fan 50, the axial fan 50 rotates to form a rotation plane, the projected area of the orthographic projection of the air intake shroud 70 longitudinally falling on the plane of the rotation plane is S1, and the projected area of the orthographic projection of one end of the extension rod connected to the air intake shroud 70 longitudinally falling on the plane of the rotation plane is S2. Wherein the ratio of S1 to S2 is 6 or more and 16 or less. Preferably, 8 ≦ S1/S2 ≦ 12. Therefore, the air inlet requirement can be guaranteed to the greatest extent, and the influence on the air inlet volume caused by the overlarge area of the end surface of the first end, connected with the axial air inlet 12, of the extension rod 20 is prevented. In one embodiment, the extension rod 20 is connected to the first end of the axial inlet 12 at a vertical positionCross-sectional area in longitudinal direction of not more than 1256mm²Not less than 314mm². In a preferred embodiment, the cross-sectional area of the first end of the extension rod 20 connected to the axial air inlet 12 in the vertical longitudinal direction is not more than 920mm²Not less than 616mm². It is particularly emphasized that the extension pole 20 has an excessively large cross-sectional area in a vertical longitudinal direction, which inevitably affects an intake air amount and a weight reduction of the whole machine, and an excessively small cross-sectional area, which reduces the reliability of the extension pole 20 due to the need to support the air duct portion 10 and the battery pack 60 by the front and rear of the extension pole 20. Therefore, the cross-sectional area of the end of the extension rod 20 connected to the axial air inlet 12 in the vertical longitudinal direction is set within the specific range, so that the air inlet volume and the performance of the garden blower can be ensured while the light weight and the reliability of the whole machine are both considered.

Further, since garden blowers are basically operated by a user holding the machine, for handheld devices, the user may experience arm fatigue during prolonged holding operations, especially for one-handed operated handheld devices. Therefore, under the condition of realizing almost the same performance, the whole machine can be substantially compressed in volume and weight, and the difficult problem to be solved is always needed. In the foregoing embodiment, by the ingenious design of the short air channel portion 10, and the size of the cross section of the overlapped air channel portion 10 is also reduced, so that the volume and the weight of the whole machine are significantly changed under the condition that the longitudinal size and the radial size are both shortened. It should be noted that one end of the air inlet protecting cover 70 is connected to the axial air inlet 12, and the other end is supported on the extension rod 20, so the air inlet protecting cover 70 affects the radial size of the whole machine, wherein one end of the air inlet protecting cover 70 is connected to the axial air inlet 12 of the air duct portion 10, so the cross-sectional size of the air duct portion 10 is reduced, and the cross-sectional size of the air inlet protecting cover 70 is also necessarily reduced, which is beneficial to reducing the size of the whole machine. Specifically, in some embodiments, the cross-sectional area of the end of the intake shroud 70 connected to the axial intake vent 12 is less than 13300mm in a direction perpendicular to the longitudinal direction²Preferably, the cross-sectional area of the end of the intake shroud 70 connected to the axial intake vent 12 in the direction perpendicular to the longitudinal direction is not less than 3800 mm²Not greater than 11300mm²。

Specifically, in one embodiment, the air inlet shroud 70 is approximately circular and has a diameter of 110mm, and the extension rod 20 has a cross-sectional area of 907mm in the radial direction²Namely, the ratio of the orthographic projection area S1 of the air inlet shield 70 along the longitudinal direction on the plane of the rotating surface to the orthographic projection area S2 of the end of the air inlet shield 70 connected with the extension rod 20 along the longitudinal direction on the plane of the rotating surface is about 10.47. Further, the intake shroud 70 extends for a distance of not less than 62mm on the fan axis of the axial flow fan 50. Therefore, the air inlet volume of the garden blower is further ensured, and the performance requirement of the garden blower can be met.

Figure 7 shows a schematic cross-sectional view of the position of the inlet shroud in a first operating state of the garden blower according to an embodiment of the present application; fig. 8 shows a schematic cross-sectional view of the inlet shroud of the garden blower of fig. 7 taken along the direction B-B.

Aiming at the layout of the thin air duct, the connection and fixation structure of the air inlet protective cover 70 and the extension rod 20 is required to be considered, so that the air inlet is not shielded as much as possible, and the loss of the air inlet amount is further reduced. In some embodiments, referring to fig. 7-8, the air inlet cover 70 has a plug portion 72 extending longitudinally a predetermined distance, the cover holes 74 are circumferentially distributed around the plug portion, the garden blower further includes a first connecting structure (not shown), and the first end of the extension rod 20 is connected to the plug portion 72 of the air inlet cover 70 through the first connecting structure. Wherein, the orthographic projection of the first connecting structure along the extension direction of the extension rod 20 on the plane of the rotation surface of the axial flow fan 50 is not basically coincident with the orthographic projection of the shield hole 74 along the extension direction of the extension rod 20 on the plane of the rotation surface. On the whole, this first connection structure is located the inner circle of air inlet guard shield 70, and guard shield hole 74 is located the periphery of grafting portion 70, and both mutually noninterfere do not shelter from each other to air inlet guard shield 70 is when connecing with extension rod 20 and is joined in marriage, and first connection structure can not occupy the area of guard shield hole 74, thereby can not influence the intake. In the embodiment shown in fig. 8, the cross-section of the insertion portion 72 along the direction perpendicular to the longitudinal extension direction of the extension rod 20 is oval, and in other embodiments, the cross-section may be circular or square, which is not limited herein.

It should be noted that an orthogonal projection of the first connecting structure along the extending direction of the extension rod 20 on the plane of the rotating surface of the axial flow fan 50 is not substantially coincident with an orthogonal projection of the shroud hole 74 along the extending direction of the extension rod 20 on the plane of the rotating surface. By substantially non-coincident is meant that the maximum linear dimension of the projection of the first attachment structure onto the plane of rotation is within 5mm of the projection of the shield aperture 74 onto the plane of rotation. Further, taking the screw fastening method as an example, the screw is inserted from the outer edge of the air intake shroud 70 and connected to the extension rod 20, and this way, the screw occupies a large size in the radial direction, so that the maximum linear size of the projection of the first connecting structure on the plane of the rotation plane and the projection of the shroud hole 74 on the plane of the rotation plane intersect is larger than 5 mm. Thus sacrificing part of the air intake area and making the installation more complicated. Therefore, in the screwing manner, the orthographic projection of the first connecting structure along the extension direction of the extension rod 20 on the plane of the rotation plane of the axial fan 50 and the orthographic projection of the shield hole 74 along the extension direction of the extension rod 20 on the plane of the rotation plane do not belong to the case of "substantial misalignment" defined above.

In some embodiments, the plug portion 72 is configured as a hollow plug hole, and the first end of the extension rod 20 is plugged and locked into the plug portion 72 to achieve a locking connection therebetween. In other embodiments, the plug portion 72 of the air intake shroud 70 may also be configured to be inserted into an interior cavity of the first end of the extension pole 20. It should be appreciated that the first end of the extension rod 20 and the insertion part 72 are wrapped around each other and extend a distance in the longitudinal direction, so that the coupling area of the extension rod 20 and the air inlet shield 70 is increased, and the coupling strength between the extension rod 20 and the air inlet shield 70 can be improved. For example, in the embodiment in which the insertion part 72 is configured as a hollow insertion hole, since the insertion part 72 has a certain extension length in the longitudinal direction, the extension rod 20 can be wrapped along the circumference of the extension rod 20, so that the connection strength and stability of the extension rod 20 and the air inlet shield 70 are better.

FIG. 9 is a schematic view illustrating a matching relationship between a positioning member of an extension rod and an air inlet cover when the positioning member is in a locked state according to an embodiment of the present disclosure; fig. 10 is a schematic structural view illustrating the extension pole when the positioning member of the extension pole shown in fig. 9 is in a natural state.

In some embodiments, as shown in fig. 9-10, the first connecting structure includes a mating member disposed on the extension rod 20 and a locking member disposed on the plug-in channel. Wherein the locking member may be defined as a positioning hole 76 in the inner wall of the mating part and the mating member may be a shape adjustable positioning member 22 disposed adjacent the outer wall of the first end of the extension rod 20 or disposed at the first end of the extension rod 20. The positioning member 22 has a locking state of engaging with the inner wall of the positioning hole 76, and in the locking state, the outer contour of the positioning member 22 radially exceeds the outer contour of the inner wall of the positioning hole 76 to limit the extension rod 20 from being pulled out from the insertion hole. Specifically, in some embodiments, the retainer 22 has a natural state (see fig. 10) in which it maintains its shape inserted into the plug-in duct, and a locking state (see fig. 9) in which it changes its shape when subjected to an external force. In a natural state, the positioning element 22 is located at a predetermined position corresponding to the positioning hole 76, and in a locked state, an outer contour of the positioning element 22 radially exceeds an outer contour of an inner wall surface of the positioning hole 76 to limit the extension rod 20 from being pulled out from the insertion hole.

Specifically, the inner wall of the socket 72 is provided with a plurality of positioning holes 76, and the plurality of positioning holes 76 are spaced apart in the circumferential direction of the socket 72. The positioning element 22 is adjustable in shape, and may be of a rigid or elastic structure. In one embodiment, when the positioning member 22 is a rigid structure, such as an aluminum plate, and is switched from the natural state to the locked state, the operator is required to use an auxiliary member to push the positioning member 22 outward, so that the positioning member 22 changes shape and expands outward. When the positioning member 22 is of an elastic structure and is switched to the locking state in the natural state, the positioning member 22 releases the accumulated elastic potential energy, so that the positioning member 22 changes the shape and is expanded outwards.

It should be emphasized that, after the air inlet protecting cover 70 is connected to the extension rod 20, the first connecting structure is entirely located inside the air inlet protecting cover 70, and the stability of the first connecting structure is ensured by accommodating the first connecting structure entirely inside the air inlet protecting cover 70. When the extension rod 20 is engaged with the air inlet protective cover 70, the positioning piece 22 of the extension rod 20 is switched from the natural state to the locking state in the positioning hole 76 so as to limit the extension rod 20 from being pulled out of the plugging hole.

In other embodiments, the engaging member may be defined as a slot recessed from the wall of the extension rod 20, the slot may be an opening penetrating from inside to outside, or may be a semi-closed groove, and the locking member may be defined as a protrusion protruding inward from the inner wall of the insertion portion 22 or the end edge of the insertion portion 72, the protrusion may be a snap, and when the insertion portion 72 is inserted into the inner cavity of the extension rod 20, the air inlet cover 70 and the extension rod 20 may form a locking engagement with the protrusion through the slot.

In some embodiments, the plug portion 72 has an open end for inserting the rod 20, and the open end may be necked inward to form a necked configuration, and the maximum outer dimension of the open end is greater than the maximum outer dimension of the rod 20 at the positioning member 22. Specifically, when the first end of the extension rod 20 is engaged with the insertion portion 72, the first end of the extension rod 20 can be easily inserted into the insertion portion 72 without using a large external force to insert the first end of the extension rod 20 into the insertion portion 72.

In some embodiments, as shown in fig. 9, the first connecting structure further includes a stopping portion 78 disposed at a distal end of the insertion portion 72, and the stopping portion 78 can abut against a distal end of the extension pole 20 to prevent the extension pole 20 from moving forward from the insertion hole of the insertion portion 72. Specifically, the stopper 78 is a stopper protruding toward the insertion hole. When the positioning element 22 is in the locked state, the first end of the extension rod 20 abuts against the stopping portion 78, and the first end of the extension rod 20 is limited between the positioning hole 76 and the stopping portion 78, so as to prevent the extension rod 20 from bouncing in the axial direction of the plugging hole. When the positioning member 22 of the extension rod 20 is engaged with the positioning hole 76, the first end of the extension rod 20 can simultaneously abut against the stopping portion 78, so as to achieve axial positioning.

In some embodiments, as shown in fig. 10, the extension rod 20 is provided with a hole 26 on the outer wall near the first end, the positioning member 22 can be formed between the hole 26 and the end edge of the first end, and the distance between the hole 26 and the end edge of the first end is configured to be equal to the distance between the positioning hole 76 and the stopping portion 78. In the embodiment, the positioning member 22 may be formed on the extension rod 20 by press forming, and the manufacturing method is simple, and does not need to use other materials, so that the cost is lower.

It is understood that the extension pole 20 not only serves to connect the operating handle 30 and the air channel portion 10, but also serves to support. Therefore, the support material of the extension pole 20 needs to have a certain strength. In some preferred embodiments, the extension rod 20 is made of an aluminum pipe, so that the extension rod has a certain supporting strength, the support made of the aluminum pipe is lighter and more portable, and the extension rod 20 has a wall thickness of 1-2 mm and a smaller volume.

In one aspect, the first end of the extension rod 20 occupies the effective ventilation area of the intake shroud 70, thereby sacrificing a portion of the intake area of the intake shroud 70. On the other hand, due to the layout of the 'thin' air duct, the air intake of the blower is inevitably greatly influenced. To compensate for the losses associated with the above-described design, an auxiliary air flow may be delivered by the extension pole 20. Specifically, as shown in fig. 9 and 10, the extension pole 20 may be substantially a hollow tubular structure having an auxiliary air duct (not shown), an air inlet and an air outlet 24 communicating with the auxiliary air duct. The airflow outlet 24 communicates with the air channel portion 10, and the airflow inlet communicates with the external airflow, and forms an auxiliary airflow through the auxiliary air channel, which is converged at the axial fan with the main airflow entering from the shroud hole 74.

In some embodiments, the airflow outlet 24 may be disposed near the first end, for example, may be disposed at a lower portion of the first end, or may be disposed directly at the end of the first end, that is, the first end is open, for communicating the auxiliary air duct and the air duct portion 10, so that the airflow in the auxiliary air duct can enter the air duct portion 10 through the airflow outlet 24. The airflow inlet may be provided near the second end and at an outer portion of the extension pole 10 disposed on the operating handle, or the airflow inlet may be provided near the second end and at an inner portion of the extension pole 20 disposed on the operating handle 30, or the airflow inlet may be provided at an end of the second end, i.e., the second end is open. In the embodiment, when the airflow inlet is located at the end of the second end or located on the extension rod 20 and located at the inner portion of the operating handle 30, in order to introduce the external airflow into the auxiliary air duct of the extension rod 20, the operating handle 30 may be provided with a secondary air inlet 36 (see fig. 7) communicated with the airflow inlet, and the secondary air inlet 36 is used for communicating the external airflow and the auxiliary air duct. The motor 40, when operated, creates a negative pressure zone near the first end of the extension pole 20, thereby drawing ambient air through the airflow inlet and into the auxiliary air duct of the extension pole 20, creating an auxiliary airflow within the extension pole 20.

Further, in order to ensure that the garden blower achieves a certain blowing force and meet the performance requirement, the radial size of the garden blower is smaller, and the whole machine is more compact, namely the air speed of the garden blower needs to be increased. The main blowing opening 14 of the main blower pipe 11 of the present application has a small cross-sectional area in the direction perpendicular to the longitudinal direction, and is capable of pressurizing the incoming air flow to achieve a high air velocity, for example, the cross-sectional area of the main blowing opening 14 of the main blower pipe 11 in the direction perpendicular to the longitudinal direction is less than 4000mm². However, since the radial dimension of the main blowing pipe 11 is small, the axial air inlet 12 and the main air outlet 14 both limit the air volume, and in order to compensate the air volume, in some embodiments, the air channel portion 10 includes the main blowing pipe 11 and the auxiliary blowing pipe 13 connected to the main blowing pipe 11. A gap for the external air stream to enter the auxiliary blowing pipe 13 can be formed between the main blowing pipe 11 and the auxiliary blowing pipe 13.

In some embodiments, the garden blower is capable of switching between a first mode of operation in which air is discharged by the auxiliary barrel 13 at a relatively high wind speed and relatively low air volume, and a second mode of operation in which air is discharged at a relatively low wind speed and relatively high air volume. Specifically, the main blower pipe 11 is in fluid communication with the auxiliary blower pipe 13, the main blower pipe 11 being supported at the distal end of the extension pole 20 with the aforementioned gap between the main blower pipe 11 and the auxiliary blower pipe 13, such that external air can enter into the auxiliary blower pipe 13 through the gap, thereby increasing the air volume of the garden blower 100. The near end of the main blowing pipe 11 is provided with the axial air inlet 12, the far end of the main blowing pipe 11 is provided with a main blowing port 14 (see fig. 4) opposite to the axial air inlet 12, and the auxiliary blowing pipe 13 is provided with an auxiliary air inlet communicated with the main blowing port 14 and a pipe orifice located at the far end of the auxiliary air inlet in the longitudinal direction, and the pipe orifice forms an air outlet. The auxiliary air inlet surrounds at least part of the main air blowing port 14, the cross-sectional area of the air outlet of the auxiliary air blowing pipe 13 in the direction perpendicular to the longitudinal direction is larger than that of the main air blowing port 14, and the gap through which the external air can flow into the auxiliary air blowing pipe 13 is formed between the inner ring of the auxiliary air inlet and the outer ring of the main air blowing port 14. By means of the auxiliary blower pipe 13, the blowing amount of the garden blower 100 can be made to meet the requirement in the case of a garden blower 100 with a high wind speed.

Further, the auxiliary barrel 13 is movably connected to the main barrel 11 for switching the garden blower between the first and second modes of operation. It should be noted that the articulated connection is understood that the auxiliary barrel 13 can be removably disconnected from the main barrel 11 and that the auxiliary barrel 13 can be retracted a predetermined distance rearward or extended forward to switch the garden blower 100 between the first and second modes of operation. Specifically, the garden blower 100 is in the first operating mode, and outside air enters from the axial air inlet 12 and is blown out from the main air outlet 14; the garden blower 100 is in a second working mode, and in the second working mode, external air enters from the axial air inlet 12 and is blown out from the nozzle of the auxiliary blowing pipe 13, a user can freely select the first working mode or the second working mode according to cleaning requirements, and the user can select a matched mode to work according to different working conditions. For example, when places such as courtyards, parks and streets which are full of fallen leaves need to be cleaned, a user can select a second working mode with relatively large air volume and relatively small wind speed so as to quickly gather the fallen leaves in a cleaning area together in unit time; the user can select the first working mode with relatively small air volume and relatively large air speed to quickly peel off the foreign matters from the ground with enough strength.

It should be noted that in the first mode of operation of the garden blower, the axial outlet of the garden blower 100 is the main outlet 14 of the main barrel 11. In the second mode of operation of the garden blower, the axial outlet of the garden blower 100 is the outlet of the auxiliary barrel.

In order to maximize the amount of air flow through the gap into the auxiliary blowing pipe 13, the auxiliary intake opening is flared and has a larger cross-sectional area in a direction perpendicular to the longitudinal direction than the outlet opening. The air speed of the air current flowing into the auxiliary blowing pipe 13 at the front end of the auxiliary air inlet is naturally reduced due to the increase of the cross-sectional area of the auxiliary air inlet. In some embodiments, the auxiliary blowpipe 13 is configured in a truncated cone shape to compress the airflow entering into the auxiliary blowpipe 13, again raising the wind speed. In addition, considering that the cross-sectional area of the outlet of the auxiliary blowing pipe 13 cannot be configured to be too small, the air volume may be affected by the excessively small size of the outlet, and specifically, the ratio of the cross-sectional area of the outlet of the auxiliary blowing pipe 13 in the direction perpendicular to the longitudinal direction to the cross-sectional area of the main blowing port 14 is between 2 and 3.5. In the embodiment, the outer wall of the auxiliary blowing pipe 13 forms an included angle of about 3 degrees to 9 degrees with the axis of the fan. So as to achieve the effect of improving the wind pressure in the auxiliary blowpipe 13 without affecting the wind quantity.

It should also be understood that the air entering the air duct portion 10 from the axial air inlet 12 is converged into an air flow moving at a high speed by the rotation of the axial fan 50, and is diffused from the axial air inlet 12 to the main air outlet 14. The air flow diffused from the axial air intake opening 12 toward the main air blowing opening 14 includes a high velocity region around the fan axis of the axial fan 50 and a low velocity region at the periphery of the high velocity region. In order to maximize the amount of air flowing into the main barrel 11, the cross-sectional area of the axial air intake opening 12 is designed to be large, and the cross-sectional area of the downstream area is maintained substantially constant while the air flows toward the main barrel opening 14. On the one hand, in order to maximize the flow velocity of the air stream to be kept at a high level, the cross-sectional area of the main blowing port 14 is smaller than that of the axial intake port 12. On the other hand, when the auxiliary blowing pipe 13 is operated, since the cross-sectional area of the auxiliary air inlet is increased, the air speed of the air current flowing into the auxiliary blowing pipe 13 at the front end of the auxiliary air inlet is naturally reduced and is mixed with the low-speed air current, but if the high-speed air current and the low-speed air current are not uniformly mixed, the blowing effect is also affected. Therefore, the cross-sectional area of the axial intake port 12 and the cross-sectional area of the main blowing port 14 together constrain and influence the final outlet wind speed. If the cross-sectional area of the axial air inlet 12 is too large, and the cross-sectional area of the air outlet at the main air blowing port 14 or the auxiliary air blowing pipe 13 is too small, the stable and high-speed air flow is not formed. In some embodiments of the present application, the ratio of the cross-sectional area at the axial air inlet 12 to the cross-sectional area of the main air blowing opening 14 is set to be less than 1.65, so that the flow velocity of the air flow is kept at a high level, and in the second operation mode, the phenomenon of uneven mixing with the low-velocity air flow does not occur, thereby avoiding air flow turbulence, ensuring the length and the cross-sectional area of the high-velocity air flow from the axial air outlet, and further improving the blowing effect of the garden blower 100.

As shown in fig. 4 to 5, in some embodiments, the main blowing pipe 11 is provided with a first locking groove 112 and a second locking groove 114 arranged at intervals along an axial direction thereof, and the auxiliary blowing pipe 13 is provided with a limiting portion 134 adapted to the first locking groove 112 and the second locking groove 114. The first engaging groove 112 is closer to the axial fan 50 and the motor 40 than the second engaging groove 114, when the limiting portion 134 is engaged with the first engaging groove 112, the main air blowing opening 14 is exposed, the external air enters from the axial air inlet 12 and is blown out from the main air blowing opening 14, and the garden blower is in the first operating mode. When the limiting portion 134 is engaged with the second engaging groove 114, the main blowing port 14 is hidden in the auxiliary blowing pipe 13, the external air enters from the axial air inlet 12 and is blown out from the pipe orifice of the auxiliary blowing pipe 13, and the garden blower is in the second operating mode. In particular to an embodiment, the main blowing pipe 11 is further provided with a guide rail (not shown) in the axial direction thereof, by means of which guide rail the auxiliary blowing pipe 13 is slidably connected to the main blowing pipe 11 in the axial direction of the main blowing pipe 11. The stopper 134 has a catching end for fitting with the first and second catching grooves 112 and 114 and a pressing end for contact-pressing, and an elastic member 136 is further provided between the pressing end and the main blowing pipe 11, the catching end and the pressing end being configured to form both ends of a lever. When pressing the end, the elastic member 136 is compressed, the clamping portion can be disengaged from the first clamping groove 112 or the second clamping groove 114, when releasing the pressing end, the elastic member 136 recovers deformation, and the clamping end is forced to be clamped into the first clamping groove 112 or the second clamping groove 114, so that axial spacing between the auxiliary blowing pipe 13 and the main blowing pipe 11 is realized.

Illustratively, in some embodiments, the nominal output voltage of the battery pack 60 is less than or equal to 20V, the capacity of the battery pack 60 is between 2Ah and 9Ah, the maximum rotational speed of the motor 40 is between 18000rpm and 35000rpm, the garden blower 100 does not weigh more than 1.8kg, preferably not more than 1.5kg, when the battery pack 60 is not connected thereto, the maximum wind speed of the garden blower 100 in the first operating mode is between 90mph and 110mph, the maximum wind volume of the garden blower 100 in the second operating mode is between 350cfm and 500cfm, and the operating time of the battery pack is not less than 6 min. Specifically, the nominal output voltage of the single battery pack 60 is 20V, the capacity of the battery pack 60 is 4Ah, the maximum rotation speed of the motor 40 is 20000rpm to 30000rpm, and the weight of the blower without the battery pack 60 connected thereto is not more than 1.5 kg. The maximum air speed of the blower in the first working mode is between 90mph and 100mph, the maximum air quantity in the second working mode is between 380cfm and 480cfm, and the working time of the battery pack is not less than 10 min.

In other embodiments, the nominal output voltage of the battery pack 60 is greater than 20V and less than 56V, the capacity of the battery pack 60 is between 2Ah and 9Ah, the maximum rotation speed of the motor 40 is between 20000rpm and 38000rpm, the weight of the garden blower 100 when the garden blower 100 is not connected with a power supply is not more than 2kg, preferably not more than 1.8kg, the maximum wind speed of the garden blower 100 in the first operation mode is between 110mph and 180mph, the maximum wind volume of the garden blower 100 in the second operation mode is between 420cfm and 650cfm, and the operation time of the battery pack is not less than 6 min. Specifically, the garden blower comprises a first battery pack and a second battery pack which supply power to the motor 40, the nominal output voltage of the first battery pack and the nominal output voltage of the second battery pack are both 20V, the capacity of the battery packs is 4Ah, the weight of the blower when the battery packs are not connected with the blower is not more than 1.8kg, and the maximum rotating speed of the motor 40 is 20000 rpm-38000 rpm. The maximum air speed of the blower in the first working mode is 130-165 mph, the maximum air quantity in the second working mode is 480-630 cfm, and the working time of the battery pack is not less than 10 min. In the prior art, the garden blowers 100 with similar performance are heavy in mass, and the garden blowers in the embodiments of the present application effectively improve the use experience of users on the premise of meeting the requirements of air volume and air speed performance.

Compared with the conventional hair dryer, the air duct portion 10 of the present application has a reduced overall length. Thus, the flow resistance of the air flow in the air duct portion 23 is reduced, and the whole machine can have a smaller volume. Specifically, the ratio of the length of the air duct part 10 in the longitudinal direction to the length of the garden blower 100 as a whole in the longitudinal direction is less than or equal to 70%, and the maximum rotation speed of the motor is set to be greater than or equal to 18000rpm and less than or equal to 40000 rpm. Preferably, the ratio of the length of the air duct part 10 in the longitudinal direction to the length of the garden blower 100 as a whole in the longitudinal direction is less than or equal to 65%, and the maximum rotation speed of the motor is set to be greater than or equal to 18000rpm and less than 38000 rpm. Specifically, the length of the whole machine is 850 mm-1000 mm, the air duct portion 10 is linear, and the length of the air duct portion 10 is not more than 600 mm. Therefore, the length of the air channel portion may be 600mm, 580mm, 560mm, 540mm, 520mm, 500mm, 480mm, 460mm, 440mm, etc., and preferably, the length of the air channel portion 10 is between 440mm and 560 mm.

Specifically, in some embodiments, the nominal output voltage of a single battery pack is less than or equal to 20V, the capacity of the battery pack is between 2Ah and 9Ah, the maximum rotation speed of the motor is between 18000rpm and 35000rpm, and the length of the air duct portion is less than or equal to 600mm, specifically 450 mm; when the nominal output voltage of a single battery pack is more than 20V and less than 56V, the maximum rotating speed of the motor is 20000 rpm-38000 rpm, the length of the air channel part is less than or equal to 570mm, and specifically can be 500 mm; the lengthwise length of garden blower 100 is typically not less than 750mm, and thus, the lengthwise length of garden blower 100 can be 850mm, 880mm, 920mm, 950mm, 989 mm.

In the present application, since the length of the air duct portion 10 is shortened and the wind speed attenuation can be reduced, the length of the main blowing pipe 11 is inevitably reduced. Specifically, the length of the main blowing pipe 11 may be configured to be not more than 450mm, specifically to an embodiment, when the nominal output voltage of the battery pack is less than or equal to 20V, for example, the nominal output voltage of an individual battery pack is not more than 20V, and the capacity of an individual battery pack is 2Ah to 5 Ah; the number of the battery packs is 1, or the number of the battery packs is 2, and the 2 battery packs are connected in series or in parallel. The maximum rotating speed of the motor is 18000 rpm-35000 rpm, and the length of the main blowing pipe 11 is less than or equal to 400mm, and specifically may be 350 mm. When the nominal output voltage of the battery pack is greater than 20V and less than 56V, for example, the nominal output voltage of a single battery pack is greater than 20V, the capacity of the single battery pack is 2 for 4Ah, and 2 battery packs are connected in series or in parallel. The maximum rotating speed of the motor is 20000 rpm-38000 rpm, the length of the main air blowing pipe 11 is less than or equal to 420mm, and the maximum rotating speed can be 380 mm.

It should be understood that when the length of the auxiliary blowing pipe 13 is too long, the air flow loss potential must be large, the high-speed wake formed by the air flow flowing out from the air outlet thereof cannot be maintained to have a desired length, and the cross-sectional area of the high-speed wake cannot be ensured to be large. Of course, the length of the auxiliary blowing pipe 13 in the longitudinal direction is too short, and the air flow entering the auxiliary blowing pipe 13 from the auxiliary air inlet in the high-speed area and the air flow entering the auxiliary blowing pipe 13 in the low-speed area are not uniformly mixed, so that the air flow is disturbed, and the air outlet effect of the air outlet of the auxiliary blowing pipe 13 is affected. Therefore, in some embodiments, the length of the auxiliary blowing pipe 13 in the longitudinal direction is set to be between 100 to 160 mm. Preferably, as in the previous embodiment, the length of the auxiliary blowing pipe 13 is between 110mm and 140 mm.

In particular, the garden blower is integrally formed into a lever structure with the user holding part as the pivot, and the two ends of the lever structure are respectively the battery pack 60 and the movement comprising the air inlet shield 70 and the air duct portion 10. Specifically, the elements attached to the distal end of the extension pole 20 are positioned as a first weight unit (including the intake shroud 70, the motor 40, the axial fan 50, the flow guide structure 80 (including the flow guide cone 82, the stationary blades 54), and an outer case wrapped around these elements), and the elements attached to the proximal end of the extension pole 20 are defined as a second weight unit (the operating handle 30 and the battery pack 60). In order to reduce the weight of the garden blower 100, it is necessary to reduce the weight of the weight units as much as possible, wherein the first weight unit and the second weight unit have a large influence on the center of gravity of the garden blower, and it is necessary to ensure that the center of gravity of the garden blower 100 after being connected to the battery pack 60 is close to the operation handle 30, so as to improve the operation experience of the user.

Fig. 11 shows a schematic position of the centre of gravity of the first weight unit, the centre of gravity of the second weight unit and the centre of gravity of the complete machine of a garden blower according to another embodiment of the present application; fig. 12 shows a schematic position of the center of gravity of the first weight unit, the center of gravity of the second weight unit and the center of gravity of the complete machine of the garden blower according to a further embodiment of the present application.

Referring to fig. 11, in some embodiments, the battery pack 60 includes a first battery pack and a second battery pack coupled to the battery pack mounting portion. For example, the nominal output voltage of the first battery pack and the nominal output voltage of the second battery pack are both 20V, the capacity of the first battery pack and the capacity of the second battery pack are 5Ah, and the total weight of the first battery pack and the second battery pack is about 1.2-1.4 kg. At this time, the weight of the second weight unit is larger than that of the first weight unit, and the gravity center of the whole machine is arranged at the back. Wherein the ratio of the weight of the second weight unit to the total weight of the garden blower 100 with the battery pack 60 installed is not more than 0.5. The weight ratio of the second weight unit to the first weight unit is not more than 2.5. Preferably, the weight ratio of the second weight unit to the first weight unit is not more than 2.3 and not less than 1.05. For example, after the entire machine is miniaturized, the weight of the second weight unit is 1.96kg, and the weight of the second weight unit is 0.88 kg.

In the longitudinal extension direction of the extension pole 20, the orthographic projection of the center of gravity of the garden blower combined with the battery pack 60 on a plane perpendicular to the rotation plane of the axial flow fan 50 is G ', the orthographic projection of the front end of the control switch 34 near the extension pole 20 on a plane perpendicular to the rotation plane of the axial flow fan 50 is K', and the orthographic projection G 'is arranged within a range of 70mm forward and backward from the orthographic projection K'. Preferably, an orthographic projection G 'of the center of gravity position of the whole machine on a plane perpendicular to the rotation plane of the axial flow fan 50 is located 35mm forward of the projection K'. By mounting the battery pack 60 on the rear side of the machine, the position of the centre of gravity G 'of the garden blower is balanced (the centre of gravity G' is herein understood to be the projection of the centre of gravity of the machine in the state of being fitted with the battery pack), and since the garden blower in this embodiment is inherently low in weight, the fatigue of the user holding the machine is greatly reduced in weight.

The distance between the orthographic projection of the center of gravity M of the first weight unit on a plane perpendicular to the rotation plane of the axial flow fan 50 and the orthographic projection G 'is L1, the distance between the orthographic projection of the center of gravity J of the second weight unit on a plane perpendicular to the rotation plane of the axial flow fan 50 and the orthographic projection G' is L2, the distance L2 is in the range of 40% -60% of the distance L1 in the longitudinal extension direction of the extension rod 20, the length of the extension rod 20 exposed to the outside is arranged in the range of 110-135 mm, and the longitudinal length of the first weight unit is between 480mm and 650 mm.

The length of the extension pole 20 exposed to the outside is the length of the extension pole 20 excluding the portion combined with the intake shroud 70 and the operating handle 30. Thus, the air channel portion 10 connected to the distal end of the extension pole 20 has a short overall length. In this way, the resistance to the flow of the air flow in the air channel portion 10 is reduced, and the maximum radial dimension of the air channel portion 10 can be shortened. Under the condition that the length and the maximum radial dimension of the air duct portion 10 are both shortened, the volume of the air duct portion 10 is greatly reduced, and the miniaturization of the whole machine is realized.

In this way, when the battery pack 60 is attached to the battery pack mounting portion, the ratio of the longitudinal distance between the center of gravity of the garden blower 100 to which the battery pack 60 is attached and the foremost end edge of the axial air outlet 12 to the longitudinal length of the garden blower 100 is not less than 0.75. Preferably, the ratio of the longitudinal distance between the center of gravity of the garden blower 100 with the battery pack 60 mounted thereon and the foremost edge of the axial air outlet 12 to the longitudinal length of the garden blower 100 is not less than 0.8. In the embodiment, the first battery pack and the second battery pack are disposed near the operating handle 30, and the projection of the center of gravity of the garden blower 100 with the first battery pack and the second battery pack on the extension pole 20 is located within the projection range of the operating handle 30 on the extension pole 20. Thus, when the garden blower 100 is connected with the battery pack 60, the reasonable configuration of the battery pack 60 can adjust the gravity center G' of the whole machine, on one hand, improve the comfort level of the handheld mode, and on the other hand, maintain the operation time of the machine, in the embodiment, the configuration of two battery packs 60 can maintain the operation time of the machine to be more than or equal to 8 min. To avoid increasing the longitudinal length of garden blower 100, the battery pack mounting portion is located below operating handle 30, and the projection of the battery pack mounting portion and operating handle 30 onto extension pole 20 at least partially coincide.

In other embodiments, as shown in FIG. 12, the battery pack mounting portion is disposed near the proximal end of the extension pole 20, the number of battery packs that power the motor 40 may be one, the nominal output voltage of the battery packs is less than or equal to 20V, the capacity of the battery packs is between 2Ah and 9Ah, and the maximum rotational speed of the motor 40 is between 18000rpm and 35000 rpm. The garden blower does not weigh more than 1.8kg when not connected with a battery pack, the maximum wind speed in the first working mode is 90-110 mph, the maximum wind amount in the second working mode is 350-500 cfm, and the working time of the battery pack is not less than 8 min. In the longitudinal extension direction of the extension rod 20, the orthographic projection of the center of gravity of the garden blower combined with the battery pack on a plane perpendicular to the rotation plane of the axial flow fan 50 is G ', the orthographic projection of the control switch 34 near the front end of the extension rod on a plane perpendicular to the rotation plane of the axial flow fan is K', and the orthographic projection G 'is configured within a range of 100mm forward and backward from the orthographic projection K', preferably, the weight of the blower without the battery pack connected thereto is not more than 1.5kg, and the projection G 'is configured within a range of 50mm forward and backward from the projection K'. By mounting the battery pack on the rear side of the whole machine, the position of the center of gravity G 'of the blower (the center of gravity G' is herein understood to be the projection of the center of gravity of the whole machine in the state of being fitted with the battery pack) is balanced, and since the weight of the blower itself in this embodiment is low, the fatigue of the user holding the machine has been greatly reduced in terms of weight.

Furthermore, in order to make the center of gravity of the whole machine as close to the operating handle 30 as possible, on one hand, the weight of the movement part is reduced, the operation comfort of the whole machine is adjusted, on the other hand, the length of the extension rod 20 is reduced, and the moment arm between the movement and the control switch 34 is shortened. However, when the length of the exposed extension rod 20 is too short, the whole length of the air duct portion 10 connected to the extension rod 20 is inevitably long, the whole miniaturization of the air duct portion 10 is affected by the increase of the air duct portion 10, and the longer the air duct portion 10 is, the larger the air flow loss is, the performance of the whole machine is affected.

Further, as shown in fig. 12, the projection of the center of gravity M of the first weight unit on the plane perpendicular to the rotation plane of the axial flow fan 50 is at a distance L1 from the projection G ', the projection of the center of gravity of the second weight unit J on the plane perpendicular to the rotation plane of the axial flow fan 50 is at a distance L2 from the projection G', the distance L2 is in the range of 60% to 80% of the distance L1 in the longitudinal extension direction of the extension rod 20, the length of the extension rod 20 exposed to the outside is in the range of 100 to 140mm, and the longitudinal length of the first weight unit is in the range of 420mm to 560 mm.

The distance L1 and the distance L2 are distances between orthogonal projections on a plane perpendicular to the rotation plane in the flat state of the blower.

In an embodiment of the application, the battery pack may be adapted to be connected to at least two different kinds of hand tools, such as battery-type hand tools like a lawn mower, a chain saw, a lawn mower, a hair dryer, a blow dryer, an electric drill, an electric saw, a pruner, a pressure washer, etc., and the second weight unit may have a weight not larger than 140% and not smaller than 105% of the first weight unit. For example, after the entire machine is miniaturized, the weight of the first weight unit is about 0.7kg, and the weight of the second weight unit is about 0.94 kg.

As shown in fig. 1, an axial air inlet 12 of a garden blower 100 in the prior art is arranged around the rearmost end of the garden blower 100, an operating handle 30 and/or a battery pack 60 is supported above an air duct portion 10, the length of the air duct portion 10 in the longitudinal direction is substantially equal to the length of the garden blower 100 in the longitudinal direction, and the length of the garden blower 100 is generally between 800 mm and 900 mm; in another garden blower 100 according to the prior art, a battery pack mounting portion is disposed at a rear end (not shown) of the air duct portion 10, and the air duct portion 10 is formed with an axial air inlet 12 at least at a side portion and a bottom portion thereof, through which external air flows into the air duct portion 10. The ratio of the length of the air channel portion 10 to the length of the garden blower 100 in the longitudinal direction is not less than 3/4. The above two garden blowers 100 cannot make the best use of the performance of the motor 40, and the air volume and the air speed of the blower are also compatible.

The inventor of the present application has found that the size of the air intake shroud 70 and the axial air intake 12 of the air duct portion 10 affects and restricts the size of the motor 40 and the size of the axial flow fan 50, and is closely related to the wind speed and the wind volume of the garden blower 100, and the length of the air duct portion 10 and the whole machine also affects whether the air flow can flow fast, and finally feeds back the wind speed and the wind volume of the garden blower 100. Therefore, when the air volume and the wind speed are predetermined values, the maximum height H and the maximum width W of the inlet hood 70 and the length L of the garden blower 100 also affect whether the performance of the motor 40 can be maximized. In some embodiments, the maximum height of the air inlet cover 70 is H, the maximum width of the air inlet cover 70 is W, wherein the ratio of the maximum height H of the air inlet cover 70 to the overall length L is less than 0.15, the ratio of the maximum width W of the air inlet cover 70 to the overall length L is less than 0.15, the air volume provided by the garden blower is greater than or equal to 350cfm and less than or equal to 650cfm, and the air speed provided is greater than or equal to 70mph and less than 185 mph. Therefore, the blowing performance and the blowing efficiency of the garden blower can be better, and the action of the high rotating speed and the movement of the small axial flow fan 50 is further maximized. Specifically, in some embodiments, the maximum height H of the intake shroud 70 is greater than 80mm and less than 130 mm; the maximum width W of the air inlet shield 70 is more than 80mm and less than 130 mm; the length L of the whole garden blower is 850 mm-1000 mm.

Illustratively, the nominal output voltage of the battery pack 60 is less than equal 20V, the capacity of the battery pack 60 is between 2 and 9Ah, the maximum rotating speed of the motor 40 is between 18000 and 35000rpm, the ratio of the maximum height of the air inlet shield 70 to the overall length of the garden blower is between 0.09 and 0.133, the ratio of the maximum width of the air inlet shield 70 to the overall length of the garden blower is between 0.09 and 0.133, the maximum wind speed of the garden blower is between 90 and 110mph, and the maximum wind volume of the garden blower is between 350 and 500 cfm. In other embodiments, the nominal output voltage of the battery pack 60 is greater than 20V and less than or equal to 56V, the capacity of the battery pack 60 is between 2Ah and 9Ah, the rotation speed of the motor 40 is between 20000rpm and 38000rpm, the ratio of the maximum height of the air inlet shield 70 to the overall length of the garden blower is between 0.11 and 0.16, the ratio of the maximum width of the air inlet shield 70 to the overall length of the garden blower is between 0.11 and 0.16, the maximum wind speed of the garden blower is between 110mph and 160mph, and the maximum wind volume of the garden blower is between 420cfm and 650 cfm. Thus, the performance of the motor 40 can be utilized to the best, and the air quantity and the air speed of the blower reach the better level.

The garden blower 100, the motor 40, the axial flow fan 50 and the flow guiding structure 80 are arranged in the air duct portion 10, and are longitudinally separated from the operating handle 30 for holding by a certain distance, on one hand, the length of the air duct portion 10 is shortened, when the motor 40 drives the axial flow fan 50 to rotate at a high speed, the external air can be quickly and sufficiently introduced into the air duct portion 10, the air flows in quickly, the air loss is small, the sufficient air flow is quickly driven by the motor 40, the air pressure is large, the radial size of the air duct portion 10 can be reduced at the same air speed and air quantity, the air speed and the volume of the garden blower 100 are optimized, and the weight of the garden blower 100 is reduced. On the other hand, the garden blower 100 is switched between the first working mode with high wind speed and the second working mode with large wind volume by the mutual matching of the main blowpipe 11 and the auxiliary blowpipe 13, so that the performance requirements of different working conditions on the wind speed and the wind volume can be met, and the performance experience of the garden blower 100 is improved. On the other hand, the motor 40, the axial flow fan 50, the air duct portion 10, the air volume and the air speed are parameterized and reasonably configured to form a pattern of the high-rotation-speed motor 40 and the small axial flow fan 50, so that the performance requirements of the garden blower 100 can be met while the small size and the light weight are realized.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A garden blower capable of concentrating scattered foreign matters, comprising:

the air duct part comprises an axial air inlet communicated with the outside;

a motor for providing driving force for the garden blower;

an axial fan disposed in the air duct portion;

the operating handle is used for being operated and held by a user; and

2. A garden blower as claimed in claim 1, in which the inlet shroud is configured to extend longitudinally on the fan axis of the axial fan;

wherein 6 is less than or equal to S1/S2 is less than or equal to 16.

3. A garden blower as claimed in claim 1, in which the extender has first and second ends longitudinally opposite one another, the extender being connected to the inlet shroud by the first end and the extender being connected to the operating handle by the second end;

4. A garden blower as claimed in claim 3 in which the inlet shroud is provided with a spigot which extends a predetermined distance in the direction of extension of the rod, the shroud apertures being circumferentially distributed around the spigot;

5. A garden blower as claimed in claim 4, in which the spigot is configured as a hollow spigot, the first connection structure comprising:

the positioning piece is arranged on the extension rod;

6. A garden blower as claimed in claim 5, in which, in the locked condition, the outer profile of the locating member extends radially outwardly beyond the profile of the inner wall surface of the locating aperture.

7. A garden blower as claimed in claim 5, in which the locating member also has a natural state of shape retention for insertion into the spigot, in which the locating member is in a predetermined position corresponding to the locating hole;

8. A garden blower as claimed in claim 5 in which the first coupling means further comprises a stop provided on the spigot, the stop being capable of abutting the first end of the extension pole to prevent forward movement of the extension pole from the spigot.

9. A garden blower as claimed in claim 1, wherein the air channel portion includes a main blower pipe and an auxiliary blower pipe disposed in communication with the main blower pipe, the main blower pipe being provided with the axial air inlet and a main air outlet opposite to the axial air inlet, the auxiliary blower pipe having an auxiliary air inlet communicating with the main air outlet, the auxiliary air inlet having a cross-sectional area larger than that of the main air outlet in a direction perpendicular to the longitudinal direction, and a gap between the main air outlet and the auxiliary air inlet for an external air flow to enter the auxiliary blower pipe.

10. A garden blower as claimed in claim 9, in which the garden blower is switchable by the auxiliary barrel between a first mode of operation in which air is discharged at a relatively high wind speed and relatively low air volume, and a second mode of operation in which air is discharged at a relatively low wind speed and relatively high air volume;

11. The garden blower of claim 10, wherein the nominal output voltage of the battery pack is less than or equal to 20V, the capacity of the battery pack is 2 Ah-9 Ah, the maximum rotational speed of the motor is 18000 rpm-35000 rpm, the garden blower does not weigh more than 1.5kg when the battery pack is not connected, the maximum wind speed of the garden blower in the first mode of operation is between 90 mph-110 mph, and the maximum wind volume of the garden blower in the second mode of operation is between 350 cfm-500 cfm; or

12. A garden blower as claimed in claim 11, in which the length of the tunnel portion is no more than 600 mm.

13. A garden blower as claimed in claim 10, characterised by the nominal output voltage of the battery packLess than or equal to 20V, the capacity of the battery pack is between 2Ah and 9Ah, the maximum rotating speed of the motor is between 18000rpm and 35000rpm, the diameter of the motor is less than or equal to 40mm, and the maximum effective ventilation area of the cross section of the axial air inlet, which is perpendicular to the axis of the fan, is less than 9000mm²The outer diameter of the axial flow fan is greater than or equal to 50mm and less than or equal to 67 mm; or

14. A garden blower as claimed in claim 1, in which a gap is provided between the outer edge of the blades of the axial fan and the inner wall of the tunnel portion;

the size of the gap in the radial direction is less than 1 mm.

15. A garden blower as claimed in claim 1, in which the straight line distance from the highest point of the operating handle to the lowest point of the extension pole is less than 140mm and greater than 40 mm.