A lawn mowing power device and a lawn mower having the same

Abstract

The present invention provides a mowing power device and a lawn mower having the mowing power device, belonging to the technical field of garden tools. It solves the technical problems such as poor heat dissipation effect of the mowing power device. The mowing power device includes a casing, a motor seat and a casing connecting seat that seals and fixes the casing and the motor seat. A motor is arranged in the motor seat, and the output shaft of the motor is fixedly connected to a centrifugal fan and a mowing blade; a battery compartment seat, a battery compartment cover and an air inlet that are connected to the casing are arranged on the casing, a filter grid is arranged between the battery compartment seat and the battery compartment cover, and a controller assembly located below the filter grid is arranged in the casing; a motor front end cover with a plurality of ventilation holes 1 and a motor rear end cover with a plurality of ventilation holes 2 are arranged at both ends of the motor, and a ventilation hole is opened at the bottom of the motor seat, and the air inlet and the filter grid holes, ventilation hole 1, ventilation hole 2, and ventilation hole form a heat dissipation air duct. The heat dissipation effect of the mowing power device in the present invention is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of garden tools and relates to a mowing power device on a mower and a mower with the mowing power device. Background Art

[0002] A lawn mower, also known as a weed cutter, lawn mower, lawn trimmer, etc., is a mechanical tool used to trim lawns, vegetation, etc. For a lawn mower, the more important part is the power head, which can also be called a mowing power device. The power head mainly includes a motor, a controller assembly, a lithium battery, etc. At present, the power heads of lawn mowers on the market generally have poor heat dissipation effects, which can easily lead to the motor in the power head burning out, the heat generated by the power components of the controller cannot be completely removed, and the life of the controller is shortened.

[0003] A Chinese patent (publication number: CN105940870A; publication date: 2016-09-21) discloses a power head on a lawn mower, comprising a casing, a drive head mounted on the casing, and at least one air inlet opened on the casing, at least one ventilation slot opened inside the casing, the ventilation slot and the air inlet forming a heat dissipation duct; the heat dissipation duct is used for the air flow to flow into the ventilation slot after the air inlet enters the air flow, and then the drive head blows the air flow out of the casing; a motor control board is provided in the casing, the motor control board is provided below the ventilation slot, and the air flow entering the ventilation slot is used for heat dissipation; a wind gathering hood is provided on the outside of the motor in the casing, the wind gathering hood gathers the air flow entering the ventilation slot, and the air flow is blown out from the lower part of the casing by the drive head.

[0004] When the power head in the above patent document is working, the motor rotates to drive the fan to rotate, and the wind is drawn downward from the top of the wind hood, thereby taking away the heat generated by the motor control board. Since the motor top cover is sealed (no air inlet can be opened on the motor top cover, because the lawn mower has rain requirements. When the top is opened, water will enter the motor control board from the top, which does not meet the rain safety requirements of the lawn mower), the wind can only enter from the air inlet on the lower side of the casing. This method has the following problems: 1. The air inlet plate is easy for dust or broken grass to adhere to the air inlet position. Especially for lawn mowers, when they are used for outdoor mowing, dew is easy to adhere to the air inlet plate. After a period of use, the air inlet plate loses its air intake function and cannot achieve a good cooling effect. At the same time, it is inconvenient to clean the air inlet plate, resulting in the risk of product failure. 2. The controller is outside the wind hood and the motor is inside the wind hood, resulting in the heat generated by some controller power components cannot be completely taken out. For a long time, the temperature rise of the controller will be too large and a good cooling effect cannot be achieved. 3. The structure of this power unit is too complicated. At the same time, the fan is placed inside the power unit, which makes it easy to damage the wiring harness, posing certain safety hazards. Summary of the invention

[0005] The present invention aims at the above-mentioned problems existing in the prior art and provides a lawn mowing power device. The technical problem to be solved by the present invention is: how to improve the heat dissipation effect and the safety and reliability of the lawn mowing power device.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A mowing power device, comprising a casing and a motor seat, wherein the motor seat is fixedly arranged at the bottom of the casing and a motor is arranged in the motor seat; the characteristic is that the output shaft of the motor is arranged downward and the output shaft of the motor is respectively fixedly connected with a centrifugal fan and a mowing blade; a battery compartment seat is arranged on the casing, a battery compartment cover docking with the casing is arranged at the opening of the battery compartment seat, the battery compartment cover is movably arranged and located on the upper side of the casing, at least one air inlet is arranged between the battery compartment cover and the casing, a controller assembly is arranged in the casing, a filter grid for filtering grass clippings is arranged between the air inlet and the controller assembly, and filter grid holes are opened on the filter grid; the controller assembly is obliquely arranged below the filter grid; a motor front end cover and a motor rear end cover are arranged at both ends of the motor, a plurality of ventilation holes 1 are arranged on the motor front end cover, and a plurality of ventilation holes 2 are arranged on the motor rear end cover; a ventilation opening is opened at the bottom of the motor seat, and the air inlet, the filter grid holes, the ventilation holes 1, the ventilation holes 2, and the ventilation opening form a heat dissipation air duct.

[0008] Its working principle is as follows: the lawn mowing power device in the technical solution has at least one air inlet between the battery compartment cover and the machine cover. The motor is turned on to drive the centrifugal fan to rotate. When the air flow enters between the battery compartment cover and the battery compartment seat from the air inlet, it can enter the casing cavity through the filter grid holes of the filter grid. There are power components on the controller assembly, and the power components will generate heat. The air flow entering the casing blows toward the power components on the controller assembly to take away the heat, thereby cooling the controller assembly. The casing and the motor seat are closed and fixedly connected. Part of the air flow enters the motor from the ventilation hole 2 on the rear end cover of the motor and flows out from the ventilation hole 1 on the front end cover of the motor. The air flow takes away the heat generated by the motor armature, and part of the air flow flows through the outside of the motor to take away the heat outside the motor. Then the air flow flows out from the ventilation hole at the bottom of the motor seat. In the technical solution, the airflow passes through the components that generate a large amount of heat in the lawn mowing power device, and takes away the heat, so that the heat dissipation effect of the lawn mowing power device is better; the filter grid blocks grass clippings, and the filtered grass clippings can be located between the battery compartment cover and the battery compartment seat. The battery compartment cover and the casing are detachably connected, which is convenient for cleaning grass clippings, so that the amount of heat dissipation airflow entering the casing is guaranteed; and the air inlet and the filter grid are positioned relatively high, and the filter grid is located inside the casing, so it is not easy to stick to dew and adsorb foreign matter.

[0009] In the above mowing power device, there are several filter grid holes which are parallel and spaced on the filter grid, and the width of each filter grid hole is 2mm to 4mm. The filter grid is mainly used to filter grass clippings in the airflow. When the width of the filter grid holes on the filter grid is preferably 2mm, 3mm, or 4mm, it can block grass clippings and pass sufficient heat dissipation airflow to facilitate heat dissipation of the mowing power device.

[0010] In the above-mentioned mowing power device, the controller assembly includes a double-pack switching board, a self-propelled drive board and a mowing main control board, the filter grid is arranged vertically, and the angle between the controller assembly and the filter grid is an acute angle. The power components on the self-propelled drive board and the mowing main control board are located below the filter grid in the housing, and the angle between the controller assembly and the filter grid is an acute angle. The airflow entering the housing through the filter grid holes first cools the power components of the controller assembly and takes away the heat generated by the power components, thereby achieving a rapid heat dissipation effect.

[0011] In the above mowing power device, the ratio of the total area of ​​the filter grid holes on the filter grid to the total area of ​​the ventilation openings of the motor base is 0.2 to 0.6. Since the total ventilation area of ​​the filter grid is smaller than the total ventilation opening area of ​​the motor base, the external airflow is quickly sucked into the casing under the action of the centrifugal fan, and the airflow with heat is completely forced out from the ventilation openings of the motor base, achieving a forced heat dissipation effect and a good heat dissipation effect.

[0012] In the above-mentioned mowing power device, the upper end of the motor base is fixedly connected to a housing connection base, the housing and the motor base are closed and fixedly connected through the housing connection base, the centrifugal fan is made of plastic and is located below the motor base, the mowing blade is located below the centrifugal fan, and the centrifugal fan and the mowing blade are fixed to the output shaft of the motor through plastic bolts. The mowing blade is insulated from the motor and the motor output shaft by the plastic centrifugal fan and the plastic bolts to prevent electric shock to human body.

[0013] In the above mowing power device, the ratio of the outer diameter of the ventilation opening of the motor base to the diameter of the centrifugal fan is 0.6-0.8, so that the airflow in the casing can be completely sucked out, so that the mowing power device has a better heat dissipation effect.

[0014] In the above mowing power device, the controller assembly can adjust the speed of the motor. The mowing main control board performs PWM through software, so that the motor maintains a constant speed when it is unloaded; when the controller MCU detects that the motor load current is greater than a certain value, the motor reaches full speed, and the full speed speed is greater than the no-load speed. This can reduce power consumption and save energy.

[0015] The present invention also provides a lawn mower having the above-mentioned mowing power device, which comprises a chassis, the mowing power device is mounted on the chassis, and the centrifugal fan, the mowing blade and the air duct of the chassis form a high-pressure air chamber, which is beneficial to improving the mowing efficiency and grass collecting efficiency, and can also achieve the effect of cleaning the chassis air duct.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1. In the lawn mowing power device of the present invention, the air inlet, the filter grid holes, the first ventilation hole, the second ventilation hole, and the ventilation hole form a heat dissipation duct, and the centrifugal fan forcibly sucks out the airflow with heat, so that the lawn mowing power device has a better heat dissipation effect; the heat inside and outside the controller assembly and the motor can be taken out by the airflow, which can extend the life of the controller assembly and the motor.

[0018] 2. In the lawn mowing power device of the present invention, grass clippings are filtered by the filter grid and are located between the battery compartment cover and the battery compartment seat. The battery compartment seat is movably connected to the casing, which is convenient for cleaning grass clippings. The air flow in the casing is guaranteed, thereby ensuring the heat dissipation effect of the lawn mowing power device.

[0019] 3. In the mowing power device of the present invention, the controller assembly can perform PWM through software, so that the speed of the motor when it is unloaded is lower than the speed when it is running at full speed, thereby reducing power consumption and saving energy.

[0020] 4. In the lawn mower of the present invention, the centrifugal fan, the mowing blade and the air duct of the chassis form a high-pressure air chamber, which improves the efficiency of mowing and collecting grass and also improves the cleanliness of the bottom plate air duct. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a cross-sectional view of the mowing power device Figure 1 .

[0022] Figure 2 This is a cross-sectional view of the mowing power device Figure 2 .

[0023] Figure 3 yes Figure 2 Schematic diagram of the local enlarged structure.

[0024] Figure 4 This is a three-dimensional schematic diagram of the controller assembly in the mowing power device. Figure 1 .

[0025] Figure 5 This is a three-dimensional schematic diagram of the controller assembly in the mowing power device. Figure 2 .

[0026] Figure 6 It is a top view of the front end cover of the motor in the mowing power device.

[0027] Figure 7 It is a top view of the rear end cover of the motor in the lawn mowing power device.

[0028] Figure 8 It is a top view of the motor base in the lawn mowing power device.

[0029] Fig. 9 It is a partial cross-sectional view of the lawn mowing power device.

[0030] Fig.10 It is a schematic diagram of the controller assembly controlling the motor speed in the lawn mowing power device.

[0031] Fig.11 This is a three-dimensional structure diagram of the lawn mower. Figure 1 .

[0032] Fig.12 This is a three-dimensional structure diagram of the lawn mower. Figure 2 .

[0033] In the figure, 1. casing; 2. motor seat; 2a. vent; 3. motor; 31. motor front cover; 31a. vent 1; 32. motor rear cover; 32a. vent 2; 4. casing connection seat; 5. centrifugal fan; 6. mowing blade; 7. battery compartment seat; 8. battery compartment cover; 9. air inlet; 10. filter grid; 10a. filter grid hole; 11. controller assembly; 11a. double pack switching board; 11b. self-propelled drive board; 11c. mowing main control board; 12. plastic bolts; 13. chassis. DETAILED DESCRIPTION

[0034] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0035] Embodiment 1:

[0036] like Figures 1 to 3As shown, the mowing power device in this embodiment includes a casing 1, a motor base 2 and a casing connecting base 4. The casing 1 and the motor base 2 are closed and fixedly connected through the casing connecting base 4. A battery compartment seat 7 is arranged in the casing 1. The battery compartment seat 7 is equipped with a lithium battery located in the casing 1. A battery compartment cover 8 docking with the casing 1 is also provided on the battery compartment seat 7. At least one air inlet 9 is provided between the battery compartment cover 8 and the casing 1, preferably one air inlet 9. A filter grid 10 for filtering grass clippings is also provided between the battery compartment seat 7 and the battery compartment cover 8. A plurality of filter grid holes 10a are arranged vertically and parallelly at intervals on the filter grid 10. The width of each filter grid hole 10a is 2 mm to 4 mm, preferably 2 mm, 3mm, 4mm, a controller assembly 11 is obliquely provided below the filter grid 10 in the casing 1, the filter grid 10 is vertically arranged, and the angle β between the controller assembly 11 and the filter grid 10 is an acute angle, a motor front end cover 31 and a motor rear end cover 32 are provided at both ends of the motor 3, a plurality of ventilation holes 1 31a are provided on the motor front end cover 31, and a plurality of ventilation holes 2 32a are provided on the motor rear end cover 32, the bottom of the motor base 2 is close to the motor front end cover 31 and is provided with a ventilation port 2a, a centrifugal fan 5 and a mowing blade 6 are fixedly connected to the output shaft of the motor 3, and the air inlet 9, the filter grid hole 10a, the ventilation hole 1 31a, the ventilation hole 2 32a, and the ventilation port 2a form a heat dissipation air duct.

[0037] like Figures 4 to 9 As shown, B is the outer diameter of the vent 2a of the motor base 2, C is the diameter of the centrifugal fan 5, the controller assembly 11 includes a double-pack switching board 11a, a self-propelled drive board 11b and a mowing main control board 11c, and the self-propelled drive board 11b and the mowing main control board 11c are provided with heat-generating power components; the ratio of the total area of ​​a plurality of filter grid holes 10a on the filter grid 10 to the total area of ​​the vent 2a at the bottom of the motor base 2 is 0.2-0.6, preferably 0.4; the ratio of the outer diameter of the vent 2a of the motor base 2 to the diameter of the centrifugal fan 5 is 0.6-0.8, preferably 0.7; the motor 3 is started, the centrifugal fan 5 rotates, and the external airflow is quickly sucked into the casing 1, and the airflow takes out the heat of the power components of the controller assembly 11 and the motor 3 inside and outside, and is forcibly sucked out from the vent 2a of the motor base 2 by the centrifugal fan 5, thereby achieving the effect of forced heat dissipation.

[0038] like Fig.10As shown, the lithium battery is electrically connected to the controller assembly 11 and the motor 3 respectively. The mowing main control board 11c of the controller assembly 11 performs PWM pulse width adjustment through software, so that the motor 3 maintains a constant speed when it is unloaded; when the controller MCU detects that the load current of the motor 3 is greater than a certain value, the motor 3 reaches full speed operation, and at this time, the full speed speed of the motor 3 is greater than the low speed speed of the motor 3 when it is unloaded. The mowing main control board 11c controls the motor 3 to run at a low speed of preferably 2900r / min. When the controller MCU detects that the load current value of the motor 3 is preferably 10A, the full speed speed range of the motor 3 is 3000-4000r / min. This can reduce power consumption and save energy.

[0039] like Figure 1 As shown, the centrifugal fan 5 is made of plastic, and the centrifugal fan 5 and the mowing blade 6 are fixed to the output end of the motor 3 by plastic bolts 12. The centrifugal fan 5 isolates the mowing blade 6 from the motor 3, and the centrifugal fan 5 and the mowing blade 6 are fixed by plastic bolts 12, so that the mowing blade 6 is insulated from the output shaft of the motor 3 to prevent electric shock to the human body.

[0040] Embodiment 2:

[0041] like Fig.11 and Fig.12 As shown, this embodiment discloses a lawn mower, including a chassis 13 and the lawn mowing power device in the first embodiment, the lawn mowing power device is installed on the chassis 13, the centrifugal fan 5, the lawn mowing blade 6 and the air duct of the chassis 13 form a high-pressure air chamber, which can improve the efficiency of the lawn mower in discharging and collecting grass, and the formation of the high-pressure air chamber can improve the cleanliness of the air duct of the chassis 13.

[0042] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A lawn mowing power device, comprising a housing (1) and a motor base (2), wherein the motor base (2) is fixedly mounted at the bottom of the housing (1) and a motor (3) is arranged inside the motor base (2); characterized in that: The output shaft of the motor (3) is arranged downwards and a centrifugal fan (5) and a mowing blade (6) are respectively fixedly connected to the output shaft of the motor (3); a battery compartment seat (7) is provided on the housing (1); a battery compartment cover (8) is provided at the opening of the battery compartment seat (7) and is connected to the housing (1); the battery compartment cover (8) is movably arranged and is located on the upper side of the housing (1); at least one air inlet (9) is provided between the battery compartment cover (8) and the housing (1); a controller assembly (11) is provided in the housing (1); a filter grid (10) for filtering grass clippings is provided between the air inlet (9) and the controller assembly (11); The filter grid (10) is provided with a filter grid hole (10a); the controller assembly (11) is obliquely arranged below the filter grid (10); a motor front end cover (31) and a motor rear end cover (32) are arranged at both ends of the motor (3); the motor front end cover (31) is provided with a plurality of ventilation holes (1) (31a), and the motor rear end cover (32) is provided with a plurality of ventilation holes (2) (32a); a ventilation port (2a) is provided at the bottom of the motor base (2); the air inlet (9) and the filter grid hole (10a), ventilation hole (1) (31a), ventilation hole (2) (32a), and ventilation port (2a) form a heat dissipation air duct; The upper end of the motor seat (2) is fixedly connected to a casing connection seat (4); the casing (1) and the motor seat (2) are closed and fixedly connected via the casing connection seat (4); the centrifugal fan (5) is located below the motor seat (2); and the mowing blade (6) is located below the centrifugal fan (5).

2. The mowing power device according to claim 1, characterized in that: There are a plurality of filter grid holes (10a) which are distributed in parallel and at intervals on the filter grid (10), and the width of each filter grid hole (10a) is 2 mm to 4 mm.

3. The mowing power device according to claim 2, characterized in that: The controller assembly (11) comprises a double-pack switching board (11a), a self-propelled driving board (11b) and a mowing main control board (11c); the filter grid (10) is arranged vertically; and the angle between the controller assembly (11) and the filter grid (10) is an acute angle.

4. The mowing power device according to claim 3, characterized in that: The ratio of the total area of ​​the filter grid holes (10a) on the filter grid (10) to the total area of ​​the ventilation openings (2a) of the motor base (2) is 0.2 to 0.

6.

5. The mowing power device according to claim 1, 2, 3 or 4, characterized in that: The centrifugal fan (5) is made of plastic, and the centrifugal fan (5) and the mowing blade (6) are fixed on the output shaft of the motor (3) by means of plastic bolts (12).

6. The mowing power device according to claim 5, characterized in that: The ratio of the outer edge diameter of the ventilation opening (2a) of the motor base (2) to the diameter of the centrifugal fan (5) is 0.6 to 0.

8.

7. The mowing power device according to claim 6, characterized in that: The controller assembly (11) can adjust the rotation speed of the motor (3) through PWM pulse width modulation.

8. A lawn mower, characterized in that: A lawn mowing power device comprising any one of claims 1 to 7.

9. The lawn mower according to claim 8, characterized in that The lawn mower comprises a chassis (13), the centrifugal fan (5) and the mowing blade (6) are located below the chassis (13), and a high-pressure air chamber is formed between the centrifugal fan (5), the mowing blade (6) and the chassis (13).

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