Grass trimmer

Abstract

The utility model discloses a grass trimmer, and belongs to the technical field of garden tools. The grass trimmer comprises a main machine and a grass trimming device, the grass trimming device comprises a grass trimming head and a power head, and the power head is located above the grass trimming head and can drive the grass trimming head to rotate; the power head comprises: a casing; at least part of the motor is located in the machine shell; the airflow part is located below the motor, at least part of the airflow part is located in the machine shell, the airflow part can generate airflow when rotating around the first axis, and at least part of the airflow flows in the extending direction of the first axis. According to the grass trimmer, the airflow piece is arranged below the motor, the airflow generated by the airflow piece can enable the grass trimming head to generate the upward force vector, the weight of the grass trimming head can be reduced, an operator can operate the grass trimmer with less strength, the user experience is improved, and meanwhile heat dissipation can be conducted on the motor.

Description

Technical Field

[0001] The present application relates to a garden tool, and more particularly to a grass trimmer. Background Art

[0002] A grass trimmer belongs to an electric tool for gardening, and its main purpose is to trim the lawn or remove weeds by cutting grass clippings.

[0003] Existing grass trimmers often drive the grass head to rotate through a prime mover (such as an electric motor or a gasoline engine) with a rotating output shaft, thereby driving the cutting element to perform cutting. The motor of the grass trimmer is arranged at one end of the grass head, resulting in a heavier weight at one end of the grass head. When the user uses the grass trimmer for grass cutting operations, more effort is required to operate the grass trimmer, and the experience is poor. In addition, the heat dissipation problem of the motor needs to be considered.

[0004] This section provides background information related to the present application, and these background information are not necessarily prior art. Summary of the Invention

[0005] An object of the present application is to solve or at least mitigate some or all of the above problems. To this end, the object of the present application is to provide a grass trimmer.

[0006] To achieve the above object, the present application adopts the following technical solution: A grass trimmer includes a main body and a grass cutting device. The grass cutting device includes a grass head and a power head. The power head is located above the grass head and can drive the grass head to rotate. The power head includes: a housing; a motor located inside the housing; an air flow member located below the motor, and at least part of the air flow member is located inside the housing. The air flow member can generate an air flow when rotating around a first axis, and at least part of the air flow passing through or flowing out of the air flow member flows along the extending direction of the first axis.

[0007] In some embodiments, the air flow generated by the air flow member blows towards the grass head along the first axis direction.

[0008] In some embodiments, the housing includes:

[0009] A first housing, the motor is arranged inside the first housing;

[0010] A second housing, connected to the lower part of the first housing and covering the outer periphery of the air flow member.

[0011] In some embodiments, the air flow member can rotate relative to the second housing.

[0012] In some embodiments, the second housing and the air flow member are integrally formed.

[0013] In some embodiments, the shape of the second housing is adapted to the outer shape of the air flow member.

[0014] In some embodiments, the first housing and the second housing are fixedly connected.

[0015] In some embodiments, the motor includes:

[0016] A stator, connected to the housing;

[0017] A rotor, connected to at least the air flow member and driving the air flow member to rotate.

[0018] In some embodiments, the air flow member is an axial flow fan or a centrifugal fan.

[0019] In some embodiments, the number of fan blades of the air flow member is not more than 16.

[0020] In some embodiments, the width of the fan blades of the air flow member is not less than 6 mm.

[0021] To achieve the above object, the present application also adopts the following technical solution: A grass trimmer, including a main body and a grass trimming device, the grass trimming device includes a grass trimming head and a power head, the power head is located above the grass trimming head and can drive the grass trimming head to rotate; the power head includes: a housing; a motor, at least partially accommodated in the housing; an air flow member, which can generate an air flow when rotating around a first axis, and at least part of the air flow passing through or flowing out of the air flow member flows along the extending direction of the first axis.

[0022] The beneficial effect of the present application is that: In the grass trimmer of the present invention, an air flow member is provided below the motor, and the air flow member is at least partially located inside the housing. The air flow member can generate an air flow when rotating around the first axis, thereby dissipating heat from the motor. At least part of the air flow flows along the extending direction of the first axis, so that an upward force vector is generated on the grass trimming head, which can reduce the weight of the grass trimming head, thereby helping the operator to operate the grass trimmer with less effort and improving the user experience. Description of the Drawings

[0023] Figure 1 is a schematic structural diagram of a grass trimmer in an embodiment provided by the present application;

[0024] Figure 2 is a schematic structural diagram of the grass trimming device of the grass trimmer provided by the present application;

[0025] Figure 3 is an exploded view of the grass trimming device of the grass trimmer provided by the present application;

[0026] Figure 4 is a cross-sectional view of the grass trimming device of the grass trimmer provided by the present application;

[0027] Figure 5 is an exploded view of the grass trimming device of the grass trimmer provided by this application;

[0028] Figure 6 is a perspective view of the second housing and the air flow member of the grass trimmer provided by this application;

[0029] Figure 7 is a schematic structural view of the grass trimmer in another embodiment provided by this application.

[0030] In the figure:

[0031] 10 - Main body; 11 - Operating device; 12 - Power supply;

[0032] 20 - Grass trimming device; 21 - Cutting element; 22 - Grass trimming head; 23 - Power head;

[0033] 231 - First housing; 232 - Second housing; 233 - Motor; 234 - Air flow member; 235 - Housing;

[0034] 2311 - Accommodating portion; 2312 - Connecting portion; 2331 - Output shaft; 2341 - Air flow;

[0035] 30 - Connecting device; 31 - Hollow tube;

[0036] 100 - Grass trimmer; 101 - First axis. Detailed implementation manners

[0037] Before explaining in detail any embodiment of this application, it should be understood that this application is not limited to the structural details and component arrangements set forth in the following description or shown in the above drawings.

[0038] In this application, the terms "comprise", "include", "have" or any other variant thereof are intended to cover a non - exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device comprising that element.

[0039] In this application, the term "and / or" describes the associated relationship of associated objects and indicates that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in this application, the character " / " generally represents an "and / or" relationship between the associated objects before and after.

[0040] In this application, the terms "connect", "combine", "couple", and "mount" can be direct connections, combinations, couplings, or mounts, or can be indirect connections, combinations, couplings, or mounts. Among them, by way of example, a direct connection means that two parts or components are connected together without the need for an intermediate member, and an indirect connection means that two parts or components are respectively connected to at least one intermediate member, and these two parts or components are connected through the intermediate member. In addition, "connect" and "couple" are not limited to physical or mechanical connections or couplings, and can include electrical connections or couplings.

[0041] In this application, those of ordinary skill in the art will understand that relative terms used in combination with a quantity or condition (such as "about", "approximately", "substantially", etc.) are intended to include the recited value and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances resulting from manufacturing, assembly, use, etc. associated with a particular value. Such terms should also be considered to disclose a range defined by the absolute values of two endpoints. The relative term may refer to a plus or minus a certain percentage (such as 1%, 5%, 10% or more) of the indicated value. A numerical value without the use of a relative term should also be disclosed as a particular value having a tolerance. In addition, when expressing a relative angular positional relationship (such as substantially parallel, substantially perpendicular), "substantially" may refer to a plus or minus a certain number of degrees (such as 1 degree, 5 degrees, 10 degrees or more) based on the indicated angle.

[0042] In this application, those of ordinary skill in the art will understand that the functions performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the functions performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0043] In this application, the directional terms such as "upper", "lower", "left", "right", "front", "rear", etc. are described based on the orientation and positional relationship shown in the drawings, and should not be construed as a limitation on the embodiments of this application. In addition, in the context, it should also be understood that when it is mentioned that one element is connected "above" or "below" another element, it can not only be directly connected "above" or "below" another element, but also be indirectly connected "above" or "below" another element through an intermediate element. It should also be understood that the directional terms such as the upper side, the lower side, the left side, the right side, the front side, the rear side, etc. not only represent the positive direction, but can also be understood as the side direction. For example, the lower side can include directly below, lower left, lower right, lower front, and lower rear, etc. Embodiment

[0044] This embodiment provides a lawn mower 100, as Figure 1As shown, the lawn mower 100 includes a main body 10, a grass cutting device 20, and a connecting device 30 connecting the main body 10 and the grass cutting device 20.

[0045] Among them, the main body 10 includes an operating device 11 and a power source 12. The main body 10 is located at the rear end of the lawn mower 100, where the power source 12 is used to provide a power source for the lawn mower 100. The power source 12 includes a power source housing. The power source 12 can be a battery pack, and the battery pack is detachably installed at the power source housing at the rear end of the lawn mower 100. It can be understood that the power source 12 can also be alternating current connected to the municipal power grid. The operating device 11 is used to control whether the power source 12 provides a power source for the grass cutting device 20. The operating device 11 includes an operating handle (not shown). The operating handle includes a handle housing and a main control switch, and the main control switch is used for manual operation to control whether the lawn mower 100 operates.

[0046] The grass cutting device 20 is located at the front end of the lawn mower 100, and it includes a cutting element 21, a grass cutting head 22, and a power head 23.

[0047] The cutting element 21 is used to contact the grass clippings to achieve cutting. In the Figure 1 shown embodiment, the cutting element 21 is a grass cutting string. Of course, the cutting element 21 can also use other cutting tools such as blades.

[0048] The grass cutting head 22 is used to install or store the cutting element 21, and drives the cutting element 21 to rotate when the grass cutting head 22 rotates. When the cutting element 21 is a grass cutting string, a space for storing the grass cutting string is formed inside the grass cutting head 22.

[0049] The power head 23 is located above the grass cutting head 22 and can drive the grass cutting head 22 to rotate. As Figures 2 to 5 shown, the power head 23 includes a housing, a motor 233, and an air flow member 234. The motor 233 is located inside the housing. The motor 233 is an outer rotor motor, and the outer rotor motor includes a rotor, a stator, and an output shaft 2331.

[0050] The housing includes a first housing 231 and a second housing 232 connected up and down. The first housing 231 further includes a receiving portion 2311 and a connecting portion 2312, and the receiving portion 2311 and the connecting portion 2312 are integrally formed. A receiving cavity is formed inside the receiving portion 2311, and the receiving cavity is used to receive the stator and the rotor; the connecting portion 2312 is used to connect the grass cutting device 20 to the connecting device 30, which can achieve mechanical connection on the one hand and electrical connection between the power source 12 and the power head 23 on the other hand.

[0051] The stator is connected to the housing, and the rotor is at least connected to the air flow member 234 and drives the air flow member 234 to rotate. The output shaft 2331 rotates around the first axis 101 under the drive of the rotor, so as to transmit the torque in the power head 23 to the grass cutting head 22.

[0052] Reference Figure 4 , the air flow member 234 is located below the motor 233, and at least part of the air flow member 234 is located inside the housing. The air flow member 234 can generate an air flow when rotating around the first axis 101. The air flow 2341 passing through or flowing out of the air flow member 234 flows along the extension direction of the first axis 101 and blows towards the grass trimmer head 22. Of course, only part of the air flow 2341 flowing out of the air flow member 234 may blow towards the grass trimmer head 22. For example, when part of the air flow in the air flow member 234 is restricted by other components or structures, part of the air flow cannot blow towards the grass trimmer head 22 but is dispersed in other directions. The central axis of the air flow member 234 and the output shaft 2331 of the motor 233 both extend along the direction of the first axis 101. This structure enables the air flow member 234 to obtain the maximum driving torque, and the air flow 2341 flowing out of the air flow member 234 can quickly blow towards the grass trimmer head 22 along the shortest path.

[0053] During use, the grass trimmer head 22 is perpendicular to the ground. The air flow 2341 generated by the air flow member 234 can blow towards the grass trimmer head 22 along the direction of the first axis 101, that is, generate a downward wind, so that the grass trimmer head 22 generates an upward force vector, which can reduce the weight of the grass trimmer head 22, thereby helping the operator to operate the lawn mower 100 with less effort and improving the user experience. At the same time, by arranging the air flow member 234 below the motor 233, the air flow 2341 can also flow through the motor 233 to achieve heat dissipation of the motor 233.

[0054] In this embodiment, the second housing 232 covers the outer periphery of the air flow member 234, so that as much as possible, even all of the air flow generated by the air flow member 234 blows towards the grass trimmer head 22 along the direction of the first axis 101, in order to increase the upward force vector generated by the grass trimmer head 22 and is beneficial to reducing the weight of the grass trimmer head 22.

[0055] As Figures 4 to 6 shown, in order to reduce the air flow loss of the air flow member 234 and increase the air flow rate flowing towards the grass trimmer head 22, the shape of the second housing 232 is adapted to the outer shape of the air flow member 234. Further, the lower edge of the second housing 232 is flush with the lower edge of the air flow member 234, or the lower edge of the second housing 232 slightly protrudes from the lower edge of the air flow member 234, so as to achieve the wrapping of the second housing 232 around the air flow member 234, which has a better guiding effect on the air flow generated by the air flow member 234.

[0056] In some embodiments, the air flow member 234 can rotate relative to the second housing 232. That is, the second housing 232 is fixed, and the rotor of the motor 233 is connected to the air flow member 234 to drive the air flow member 234 to rotate relative to the second housing 232. In this structure, the first housing 231 and the second housing 232 can be fixedly connected. That is, the first housing 231 and the second housing 232 are two independent components, which are processed separately and then fixedly connected.

[0057] In another embodiment, the second housing 232 and the air flow member 234 can be integrally formed. That is, the second housing 232 forms the air flow member 234, and the second housing 232 and the air flow member 234 can rotate synchronously. The rotor of the motor 233 is connected to the air flow member 234 to drive the second housing 232 and the air flow member 234 to rotate.

[0058] To achieve a better heat dissipation effect, the connecting device 30 includes a hollow tube 31 with a connecting air duct formed inside. Specifically, referring to Figure 1 and Figure 4 as shown, one end of the hollow tube 31 is connected to the connecting portion 2312 of the housing, and the other end is connected to the power supply 12 in the main machine 10, so that one end of the connecting air duct is connected and communicated with the accommodating cavity, and the other end is connected and communicated with the power supply housing. And there are device ventilation holes in the power supply housing, and the device ventilation holes communicate the inside and outside of the power supply housing. In this way, under the action of the air flow member 234, the wind near the outside of the power supply housing enters the inside of the power supply housing, then passes through the battery pack in the power supply housing, then enters the inside of the housing through the connecting air duct, and finally blows towards the grass cutting head 22 of the housing. Thus, downward wind is generated at the grass cutting head 22 and the motor 233 operating inside the housing is effectively cooled. Moreover, since the air flow also passes through the battery pack located inside the power supply housing, the battery pack can also be very well cooled.

[0059] In this embodiment, the air flow member 234 is an axial flow fan or a centrifugal fan, and there is no excessive limitation on this.

[0060] To increase the air volume, the number of fan blades of the air flow member 234 is no more than 16. And the width of the fan blades of the air flow member 234 is not less than 6 mm. Embodiment

[0061] This embodiment provides a grass trimmer, and the difference between this grass trimmer and the grass trimmer in Embodiment 1 lies in: the structure of the grass trimming device is different, specifically in the structure of the power head 23.

[0062] As Figure 7 shown, the power head 23 includes a housing 235, a motor, and an air flow member 234. The motor is located inside the housing 235. This motor is an external rotor motor, and this external rotor motor includes a rotor, a stator, and an output shaft 2331.

[0063] A receiving cavity is formed inside the housing 235, and the receiving cavity is used to house the stator and the rotor. The stator is connected to the housing 235, and the rotor is at least connected to the air flow member 234 and drives the air flow member 234 to rotate. The output shaft 2331 rotates around the first axis 101 under the drive of the rotor, so as to transmit the torque in the power head 23 to the grass trimming head 22.

[0064] The air flow member 234 is located above the motor. The air flow member 234 can generate an air flow when rotating around the first axis 101, and the air flow generated by the air flow member 234 flows along the extending direction of the first axis 101 and blows towards the grass trimming head 22. Of course, only part of the air flow generated by the air flow member 234 can also blow towards the grass trimming head 22. For example, when part of the air flow in the air flow member 234 is restricted by other components or structures, so that part of the air flow cannot blow towards the grass trimming head 22 but is dispersed in other directions. The central axis of the air flow member 234 and the output shaft 2331 of the motor both extend along the direction of the first axis 101. This structure enables the air flow member 234 to obtain the maximum driving torque, and the air flow generated by the air flow member 234 can quickly blow towards the grass trimming head 22 along the shortest path.

[0065] In this embodiment, the air flow member 234 is located outside the housing 235 and is installed on the top of the housing 235. Preferably, the outer diameter of the air flow member 234 is the same as the outer diameter of the housing 235, so that as much as possible of the air flow generated by the air flow member 234 can flow into the housing 235. Of course, in other embodiments, part of the air flow member 234 can be located inside the housing 235 and part can be located outside the housing 235, as long as the air flow member 234 can be stably installed.

[0066] During use, the grass trimming head 22 is perpendicular to the ground. The air flow generated by the air flow member 234 can blow towards the grass trimming head 22 along the first axis 101, that is, generate a downward wind, so that an upward force vector is generated on the grass trimming head 22, which can reduce the weight of the grass trimming head 22, thereby helping the operator to operate the lawn mower 100 with less effort and improving the user experience. At the same time, by arranging the air flow member 234 above the motor, the air flow can also flow through the motor during the process of flowing towards the grass trimming head 22, taking away the heat generated by the motor, so as to realize the heat dissipation of the motor.

[0067] In this embodiment, the air flow member 234 is an axial flow fan or a centrifugal fan, and there is no excessive limitation on this.

[0068] To increase the air volume, the number of fan blades of the air flow member 234 is no more than 16. And the width of the fan blades of the air flow member 234 is not less than 6 mm.

[0069] The basic principles, main features and advantages of the present application have been shown and described above. Those skilled in the art should understand that the above embodiments do not limit the present application in any form. Any technical solutions obtained by means of equivalent replacement or equivalent transformation shall fall within the protection scope of the present application.

Claims

1. A grass trimmer, comprising a main body and a grass trimming device. The grass trimming device includes a grass trimming head and a power head. The power head is located above the grass trimming head and can drive the grass trimming head to rotate. It is characterized in that The power head includes: a housing; a motor, at least partially accommodated in the housing; and, an air flow member, located below the motor, and at least part of the air flow member is located inside the housing. The air flow member can generate an air flow when rotating around a first axis, and at least part of the air flow passing through or flowing out of the air flow member flows along the extending direction of the first axis; The housing includes: a first housing, and the motor is arranged inside the first housing; and, a second housing, connected to the lower part of the first housing and guiding the air flow generated by the air flow member.

2. The grass trimmer according to claim 1, wherein the air flow generated by the air flow member blows towards the grass trimming head along the first axis direction.

3. The grass trimmer according to claim 1, wherein the second housing covers the outer periphery of the air flow member.

4. The grass trimmer according to claim 1, wherein the air flow member can rotate relative to the second housing.

5. The grass trimmer according to claim 1, wherein the second housing and the air flow member are integrally formed.

6. The grass trimmer according to claim 4, wherein the shape of the second housing is adapted to the outer shape of the air flow member.

7. The grass trimmer according to claim 4, wherein the first housing and the second housing are fixedly connected.

8. The brush cutter according to claim 1, wherein, The motor includes: a stator, connected to the housing; and, a rotor, at least connected to the air flow member and driving the air flow member to rotate.

9. The grass trimmer according to any one of claims 1-8, wherein the air flow member is an axial flow fan or a centrifugal fan.

10. The grass trimmer according to any one of claims 1-8, wherein the number of fan blades of the air flow member is not more than 16.

11. The grass trimmer according to any one of claims 1-8, wherein the width of the fan blades of the air flow member is not less than 6 mm.

12. A grass trimmer, comprising a main body and a grass trimming device. The grass trimming device includes a grass trimming head and a power head. The power head is located above the grass trimming head and can drive the grass trimming head to rotate; Characterized in that, The power head includes: a housing; a motor, at least partially accommodated in the housing; and, an air flow member, which can generate an air flow when rotating around a first axis, and at least part of the air flow passing through or flowing out of the air flow member flows along the extending direction of the first axis; the housing has the same outer diameter as the air flow member or the outer shape is adapted to each other.

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