Power head and lawn mower

Abstract

The present invention provides a power head and a lawn mower, the power head comprising a motor assembly, an energy device and a shell assembly covering the outside of the motor assembly and the energy device, the motor assembly comprising a motor seat and a motor fixed on the motor seat, the shell assembly comprising a cover shell assembled with the motor seat, the top of the cover shell is provided with an air inlet inclined toward the rear and downward and an air inlet cavity connected to the air inlet, the air inlet and the air inlet cavity are respectively provided with two and symmetrically arranged on the left and right sides of the cover shell, the air inlet cavity is a U-shaped structure with an upper opening, the cover shell covers the top of the air inlet cavity to form a closed airflow channel, the bottom of the motor seat is closed, and the side is provided with an air outlet communicating with the outside, the cooling airflow enters from the air inlet and flows into the interior of the motor along the airflow channel, and then flows out from the air outlet.

Description

Technical Field

[0001] The invention relates to a power head and a lawn mower, belonging to the technical field of garden tools. Background Art

[0002] Lawn mowers are currently the most commonly used lawn mowing equipment. As the requirements for the functions of lawn mowers increase, the power requirements for lawn mowers are also getting higher and higher.

[0003] In the prior art, the heat dissipation of the lawn mower power head is passive or active. For active heat dissipation, it is more common to place the air outlet at the blade of the bottom shell below the motor. On the one hand, such a design can use the rotation of the blade to form suction wind, and on the other hand, it can blow away grass clippings, dust, etc. attached to the blade. However, such a design still has some insurmountable defects: first, it is not suitable for lawn mowers with higher power, high current, high torque and other high heat generation; second, it is impossible to use a high-pressure water gun to clean the bottom shell and blade of the lawn mower.

[0004] In view of this, it is indeed necessary to improve the heat dissipation mechanism of the existing lawn mower to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a power head having a better heat dissipation effect.

[0006] To achieve the above-mentioned objectives, the present invention provides a power head, including a motor assembly, an energy device and a shell assembly covering the outside of the motor assembly and the energy device, the motor assembly including a motor seat and a motor fixed on the motor seat, the shell assembly including a cover shell assembled with the motor seat, the top of the cover shell is provided with an air inlet inclined toward the rear and downward and an air inlet cavity connected to the air inlet, the air inlet and the air inlet cavity are respectively provided with two and symmetrically arranged on the left and right sides of the cover shell, the air inlet cavity is a U-shaped structure with an upper opening, the cover shell covers the top of the air inlet cavity to form a closed airflow channel, the bottom of the motor seat is closed, and the side is provided with an air outlet communicating with the outside, the cooling airflow enters from the air inlet and flows into the interior of the motor along the airflow channel, and then flows out from the air outlet.

[0007] As a further improvement of the present invention, the cover shell also accommodates a control panel close to the energy device, one end of the air inlet cavity is connected to the air inlet, and the other end extends to the control panel to guide the cooling airflow entering from the air inlet to the control panel.

[0008] As a further improvement of the present invention, a heat sink is arranged on the control board, and the other end of the air inlet cavity is arranged close to the heat sink.

[0009] As a further improvement of the present invention, the motor is located below the control board, and the motor assembly also includes a fan arranged on the top of the motor. When the motor is started, the fan rotates and drives the cooling airflow at the control board into the interior of the motor.

[0010] As a further improvement of the present invention, the motor assembly also includes a wind collecting cover covering the outside of the motor and the fan, and a vent is provided on the top of the wind collecting cover to drive the cooling airflow at the control panel into the interior of the motor through the vent when the fan rotates.

[0011] As a further improvement of the present invention, at least two air outlets are provided to discharge air in different directions; an air guide rib is provided at the air outlet of the motor base, and the air guide rib is deflected and the deflection direction is tangent to the rotation direction of the cooling airflow driven by the fan, so that the airflow direction at the air outlet is consistent with the rotation direction of the fan.

[0012] As a further improvement of the present invention, when the rotation direction of the cooling airflow driven by the fan is clockwise, the deflection direction of the air guide rib is deflected to the left relative to the rotation direction of the cooling airflow.

[0013] As a further improvement of the present invention, the air inlet cavity includes a first ramp arranged close to the air inlet and a second ramp arranged away from the air inlet, the first ramp is downhill toward the air inlet, and the second ramp is uphill toward the air inlet.

[0014] As a further improvement of the present invention, the cover shell includes a first cover shell and a second cover shell assembled and fixed to each other, and an upper cover shell covering the first cover shell and the second cover shell. The first cover shell and the second cover shell are both provided with the air inlet and the air inlet cavity, and the air inlet of the first cover shell and the air inlet of the second cover shell are symmetrical with respect to the center line of the power head, and the air inlet cavity of the first cover shell and the air inlet cavity of the second cover shell are also symmetrical with respect to the center line of the power head, and the air flow channel is formed by the air inlet cavity and the upper cover shell.

[0015] Another object of the present invention is to provide a lawn mower having a better heat dissipation effect.

[0016] To achieve the above objectives, the present invention provides a lawn mower, comprising a main body, a push rod extending upward and backward from the main body, and a power head installed on the main body, the power head is the aforementioned power head, and the air inlet on the power head is arranged close to the push rod.

[0017] The beneficial effects of the present invention are as follows: the present invention provides an air inlet inclined toward the rear and downward, an air inlet cavity connected to the air inlet, and an air flow channel formed by the cover shell and the air inlet cavity on the top of the cover shell, and at the same time designs the motor seat to be closed at the bottom and provided with an air outlet communicating with the outside on the side, so that the cooling airflow can enter from the air inlet and flow into the interior of the motor along the air flow channel, and finally flow out from the air outlet, thereby forming a circulating cooling and heat dissipation system, thereby improving the heat dissipation effect of the lawn mower power head. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional diagram of the lawn mower of the present invention.

[0019] Figure 2 yes Figure 1 A perspective view of the mounting housing.

[0020] Figure 3 yes Figure 1 A three-dimensional view of the power head.

[0021] Figure 4 yes Figure 3 Exploded view of the power head shown.

[0022] Figure 5 yes Figure 4 Exploded view of the motor assembly.

[0023] Figure 6 yes Figure 5 A three-dimensional view of the motor base.

[0024] Figure 7 yes Figure 1 A cross-section of the lawn mower shown.

[0025] Figure 8 yes Figure 7 Enlarged view of the circled area.

[0026] Fig. 9 yes Figure 4 A three-dimensional view of the first cover shell.

[0027] Fig.10 yes Figure 4 A three-dimensional view of the second cover shell.

[0028] Fig.11 yes Figure 4 A three-dimensional view of the upper middle cover.

[0029] Fig.12 It is a three-dimensional view of the shell assembly after assembly. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] like Figure 1 As shown, the present invention discloses a lawn mower 100, including a main body 1, a push rod 2 extending upward and backward from the rear of the main body 1, a power head 3 installed on the main body 1, a walking wheel 5 arranged at the bottom of the main body 1, and a grass collecting bag 6 arranged at the rear of the main body 1 for collecting broken grass leaves. Since the structures of the push rod 2, the walking wheel 5 and the grass collecting bag 6 are all existing structures, they will not be described in detail here. The following description will mainly describe in detail the specific structure of the power head 3 and the connection relationship between the power head 3 and the main body 1.

[0032] like Figure 2 As shown, the main body 1 includes a mounting shell 10 with a mounting groove 11, and the mounting groove 11 is formed by being recessed downward from the middle position of the mounting shell 10 and is generally annular. A receiving hole 111 is provided on the bottom wall 110 of the mounting groove 11, so that a screw can pass through the receiving hole 111 to assemble and fix the bottom of the power head 3 to the bottom wall 110 of the mounting groove 11.

[0033] The mounting shell 10 is further provided with an annular groove 12, which is formed at the periphery of the mounting groove 11 and has a recessed depth greater than that of the mounting groove 11, so as to form a height difference between the mounting groove 11 and the annular groove 12. A water leakage hole 121 is provided in the annular groove 12, and the water leakage hole 121 is communicated with the outside, so that when the lawn mower 100 is used on rainy days or in humid areas, rainwater on the power head 3 will slide into the annular groove 12 and finally flow out from the water leakage hole 121, thereby achieving smooth discharge of the accumulated water in the mounting shell 10.

[0034] In this embodiment, four accommodating holes 111 are provided to stably install the power head 3 in the mounting shell 10; five leakage holes 121 are provided and evenly distributed in the annular groove 12 to divert the accumulated water in the annular groove 12 and ensure that all the accumulated water in the annular groove 12 is discharged.

[0035] The power head 3 is a replaceable component that can replace a small internal combustion engine and can be applied to a variety of equipment, such as outdoor power equipment, including lawn mowers, snow sweepers, cleaning machines, scarifiers, etc. The present invention will take a lawn mower as an example to explain the specific structure and function of the power head 3 in detail, but it should not be limited to this.

[0036] like Figures 3 to 8 Combined with Figure 2As shown, the power head 3 includes a motor assembly 30 accommodated in the mounting groove 11, an energy device (not shown) and a housing assembly 40 covering the motor assembly 30 and the energy device. The housing assembly 40 is provided with an air inlet 41 and an air outlet 311, and the housing assembly 40 is also provided with an air inlet cavity 42 connected to the air inlet 41. The motor assembly 30 includes a motor seat 31 assembled with the mounting shell 10, a motor 32 fixed on the motor seat 31, a fan 33 arranged on the top of the motor 32, and a wind condenser 34 covering the outside of the motor 32 and the fan 33.

[0037] The bottom of the motor base 31 is closed, and the side is provided with an air outlet 311 communicated with the outside and a waterproof rib 312 protruding from the air outlet 311 for partial shielding. The arrangement of the waterproof rib 312 allows the motor base 31 and the shell assembly 40 to be staggered up and down, that is, the installation bottom surface of the shell assembly 40 corresponding to the air outlet 311 is lower than the upper surface of the waterproof rib 312, thereby preventing rainwater from splashing into the air outlet 311 and entering the interior of the motor 32.

[0038] In addition, the upper surface of the annular groove 12 is also lower than the upper surface of the waterproof rib 312, which can prevent the accumulated water from entering the motor seat 31 from the air outlet 311. Specifically, the bottom of the motor seat 31 and the bottom wall 110 of the mounting groove 11 are locked and fixed by screws passing through the receiving hole 111, and the annular groove 12 is distributed in a circle around the outer periphery of the motor seat 31. In other words, the motor seat 31 will not block the annular groove 12, so that the rainwater flowing down from the top of the power head 3 will flow into the annular groove 12 along the shell assembly 40 of the power head 3, and finally be discharged from the water leakage hole 121 in the annular groove 12.

[0039] It should be noted that: the air outlet 311 can be set around the bottom side of the motor seat 31, that is, at least two air outlets 311 can be set. In the embodiment of the present invention, three air outlets 311 are set to discharge air in three directions. Because the air outlet 311 is set close to the bottom of the motor seat 31, and the waterproof rib 312 is staggered with the shell assembly 40 up and down and has a certain height, rainwater will not splash into the air outlet 311, and the accumulated water in the annular groove 12 will not flow back from the air outlet 311 into the motor seat 31 due to the large amount, and affect the motor 32.

[0040] Since the air inlet 41 and the air outlet 311 of the power head 3 are both located above the bottom shell of the lawn mower 100 and the bottom of the motor base 31 is closed, when a high-pressure water gun is used to clean the bottom shell and the blade of the lawn mower 100, the bottom shell can play a good blocking role and water will not flow into the motor 32.

[0041] The air outlet 311 is provided with an air guide rib 313, which is deflected and the deflection direction is tangent to the rotation direction of the cooling airflow driven by the fan 33, so that the airflow direction at the air outlet 311 is consistent with the rotation direction of the fan 33. Preferably, when the rotation direction of the cooling airflow driven by the fan 33 is clockwise, the deflection direction of the air guide rib 313 is deflected to the left relative to the rotation direction of the cooling airflow. This design will greatly improve the exchange efficiency of cold and hot air, and can efficiently discharge the heat generated by the lawn mower 100 during operation.

[0042] The waterproof rib 312 is formed between two adjacent wind guide ribs 313, and a first slope 3120 inclined downward is formed on the side of the waterproof rib 312 away from the annular groove 12, and a second slope 3121 inclined upward is provided on the side of the waterproof rib 312 close to the annular groove 12 to guide the airflow inside the motor 32 to flow smoothly out from the air outlet 311, and at the same time, the second slope 3121 can also make the water splashed on the second slope 3121 flow to the annular groove 12.

[0043] The motor 32 is provided with a motor shaft 321, and the motor shaft 321 is connected to the working components (including blades) of the lawn mower 100 to transmit power to the working components, thereby driving the lawn mower 100 to perform a mowing action. The fan 33 is provided on the top of the motor 32 and connected to the rotor of the motor 32, so that when the motor 32 is started, the fan 33 can be driven to rotate. During the rotation of the fan 33, the external cooling airflow is driven to enter from the air inlet 41, flow along the air inlet cavity 42, pass through the motor 32, and finally flow out from the air outlet 311.

[0044] The top of the wind collecting cover 34 is provided with a vent 341, and cooling air flows into the motor 32 from the vent 341, thereby removing heat generated during the operation of the motor 32. The wind collecting cover 34 is connected and fixed to the motor base 31 by screws (not shown) to surround the motor 32 and the fan 33.

[0045] A groove 314 is concavely formed on the inner side wall of the bottom of the motor base 31, and the groove 314 is located below the motor 32. An opening 3140 is formed at one end of the groove 314 close to the air outlet 311, and the opening 3140 is communicated with the outside to discharge water entering the groove 314. In other words, even if a small amount of accumulated water enters the motor base 31, it will quickly flow to the bottom of the motor base 31 under the action of gravity, and gather in the groove 314, and finally be discharged from the opening 3140. With such a configuration, the waterproof performance of the lawn mower 100 of the present invention is greatly improved.

[0046] The opening 3140 is designed as a dark window structure, so that when the cavity at the bottom of the motor base 31 is flushed, water will not enter the motor base 31 and will not affect the motor 32.

[0047] The motor base 31 is also provided with a through hole 315 and an annular groove 316 at the middle position of the bottom. The through hole 315 is opened at the bottom center of the motor base 31 to allow the motor shaft 321 to pass through. The annular groove 316 is provided on the outside of the through hole 315, and the inner and outer sides of the annular groove 316 are provided with clamping walls 318. The height of the clamping walls 318 is slightly higher than the bottom surface of the motor base 31. In other words, the two clamping walls 318 protrude beyond the bottom surface of the motor base 31, and the annular groove 316 is formed between the two clamping walls 318. There are four grooves 314, which are evenly distributed on the periphery of the annular groove 316.

[0048] The motor 32 is located above the annular groove 316, and a wool felt 317 is contained in the annular groove 316. The height of the wool felt 317 is greater than the depth of the depression of the annular groove 316 (which can also be understood as the height of the clamping wall 318), so that the wool felt 317 will protrude from the annular groove 316. During the installation of the motor 32, the wool felt 317 will be pressed downward and outward to deform the wool felt 317. At this time, the wool felt 317 can be used to connect the motor 32 and the annular groove 316 and seal the gap between the motor 32 and the annular groove 316, thereby achieving a sealing and waterproofing effect. Of course, in other embodiments, the wool felt 317 can also be replaced by other elastic sealing materials, such as rubber rings.

[0049] The energy device is preferably a battery pack, which supplies power to the motor 32 and other electronic components. The power head 3 is provided with a battery compartment 50 for accommodating the battery pack, and the battery compartment 50 and the housing assembly 40 are respectively injection molded and assembled together, but the present invention is not limited thereto.

[0050] The battery pack contains multiple battery cells. In the present embodiment, the battery cells are arranged in the longitudinal direction of the battery pack. In other embodiments, the battery pack may have different shapes, and the battery cells may also be arranged in other directions. Depending on the number and combination of battery cells, the battery pack may output different voltages. In the present embodiment, the battery pack is an 80V battery pack. Of course, battery packs of other voltages are still within the protection scope of the present invention. In the present invention, the number of battery packs is at least two, and the two battery packs are arranged side by side in the transverse direction of the power head 3, and are both located in the battery compartment 50.

[0051] like Figures 9 to 12 Combined with Figure 3 , Figure 4As shown, the housing assembly 40 includes a cover shell assembled with the motor base 31, and the cover shell includes a first cover shell 43 and a second cover shell 44 distributed on the left and right, an upper cover shell 45 covering the first cover shell 43 and the second cover shell 44, and a flip cover 46 that can be flipped relative to the upper cover shell 45. During installation, the first cover shell 43 and the second cover shell 44 are first assembled and fixed to the motor base 31, and then the upper cover shell 45 is fixed to the top of the first cover shell 43 and the second cover shell 44, and finally the flip cover 46 is assembled and fixed to the upper cover shell 45.

[0052] The first cover shell 43 and the second cover shell 44 are assembled and fixed to each other, and a convex rib 431 is provided on the first cover shell 43, and a corresponding receiving groove 441 is provided on the second cover shell 44. The convex rib 431 is received in the receiving groove 441, which not only enables the first cover shell 43 to be assembled and fixed to the second cover shell 44, but also seals the installation gap between the first cover shell 43 and the second cover shell 44, thereby achieving better installation stability and better waterproof effect.

[0053] The air inlet 41 and the air inlet cavity 42 are both provided at the top of the first cover shell 43 and the second cover shell 44. Since the air inlet 41 on the first cover shell 43 and the air inlet 41 on the second cover shell 44 are symmetrically arranged with respect to the center line of the power head 3, and the air inlet cavity 42 on the first cover shell 43 and the air inlet cavity 42 on the second cover shell 44 are also symmetrically arranged with respect to the center line of the power head 3, the following description will take the air inlet 41 and the air inlet cavity 42 on the first cover shell 43 as an example for detailed description.

[0054] The air inlet 41 is arranged at the left rear of the first housing 43 (i.e., arranged near the push rod 2) and is inclined toward the rear and downward direction, so that when the lawn mower 100 is placed on the ground and exposed to rain, rainwater cannot enter the power head 3 from the air inlet 41. The air inlet cavity 42 includes a first ramp 421 arranged near the air inlet 41, a second ramp 422 arranged away from the air inlet 41, and a guide piece 423 arranged beside the first ramp 421 and the second ramp 422. The first ramp 421, the second ramp 422, the guide piece 423 and the inner side wall of the first housing 43 together surround the air inlet cavity 42 into a U-shaped structure with an upper opening.

[0055] The first ramp 421 slopes downward toward the air inlet 41, and the second ramp 422 slopes upward toward the air inlet 41. With this arrangement, even if water drops splash into the air inlet 41, they will slide down the first ramp 421 and flow out of the air inlet 41, and the waterproof effect is better. When the upper cover 45 is installed on the first cover 43 and the second cover 44, the U-shaped air inlet cavity 42 and the upper cover 45 together form a closed air flow channel 424 (see the details). Fig.12 ), and the air flow channel 424 extends from the rear end to the front end of the power head 3.

[0056] In order to prevent grass clippings, dust and other debris from entering the power head 3 along with the cooling airflow and causing damage to the motor 32 and electronic components, a filter element (not shown) is provided in the air inlet chamber 42. In this embodiment, the filter element is a sponge. In order to fix the sponge in the air inlet chamber 42, a fixing bracket 411 is also provided at the air inlet 41 to fix the sponge.

[0057] The first cover shell 43 is provided with a first water retaining extension 432, and the second cover shell 44 is provided with a second water retaining extension 442. The first water retaining extension 432 and the second water retaining extension 442 are connected to each other and are located around the battery compartment 50. When the upper cover shell 45 is installed on the first cover shell 43 and the second cover shell 44, the two water retaining extensions can fill the gap between the upper cover shell 45 and the first cover shell 43 and the second cover shell 44, so that rainwater will not penetrate from the connection between the upper cover shell 45 and the first cover shell 43 and the second cover shell 44.

[0058] The motor assembly 30 is housed in the rear of the first cover shell 43 and the second cover shell 44 (i.e., close to the push rod 2) and is covered by the rear end of the upper cover shell 45. The battery compartment 50 is arranged in the front of the first cover shell 43 and the second cover shell 44 to separate the motor assembly 30 and the battery pack.

[0059] The air inlet 41 and the air inlet cavity 42 are covered by the rear end of the upper cover 45, and a through hole 452 matching the battery compartment 50 for plugging and unplugging the battery pack is provided at the front end of the upper cover 45, so that the battery pack can be put into the battery compartment 50 through the through hole 452. The flip cover 46 covers the through hole 452 and the top of the battery compartment 50, and the flip cover 46 can be opened and closed relative to the upper cover 45 to perform the plugging and unplugging operation of the battery pack.

[0060] A third water retaining extension 451 is provided at the position where the upper cover 45 is connected to the flip cover 46 to seal the gap between the upper cover 45 and the flip cover 46, so that rainwater will not enter the battery compartment 50 from the connection between the upper cover 45 and the flip cover 46. Of course, the flip cover 46 itself can prevent rainwater or other liquids from entering the battery compartment 50, and the provision of the third water retaining extension 451 makes the waterproof effect better. The first water retaining extension 432, the second water retaining extension 442 and the third water retaining extension 451 form a whole water retaining extension surrounding the through hole 452 to protect the battery compartment 50 and prevent rainwater from entering the battery compartment 50 and damaging the battery pack.

[0061] The top rear end of the housing assembly 40 is recessed from bottom to top to form a gripping cavity 47, which is formed on one side of the housing assembly 40 close to the push rod 2 and on the center line of the power head 3. The gripping cavity 47 can be used as a rear handle, so that when carrying the lawn mower 100, there is no need to add additional handle parts, and the left and right hands can be directly held by the front handle 7 and the rear handle 47 respectively for carrying. The distance between the front and rear handles is designed to be shorter than the length of the arm, so that the arm is most comfortable to bear the force, so that it can not only ensure the balance of the machine and save labor in carrying, but also increase the strength of the housing assembly 40.

[0062] The side of the first cover shell 43 close to the second cover shell 44 is recessed from bottom to top to form a first L-shaped cavity 471, and the first L-shaped cavity 471 is arranged close to the top of the first cover shell 43; the side of the second cover shell 44 close to the first cover shell 43 is recessed from bottom to top to form a second L-shaped cavity 472, and the second L-shaped cavity 472 is arranged close to the top of the second cover shell 44; the holding cavity 47 is formed by the combination of the first L-shaped cavity 471 and the second L-shaped cavity 472.

[0063] Preferably, the first L-shaped cavity 471 and the second L-shaped cavity 472 are arranged symmetrically with respect to the center line of the power head 3, and the first L-shaped cavity 471 and the second L-shaped cavity 472 are both rounded and smoothly transitioned to ensure comfortable grip. The width of the grip cavity 47 is greater than 80 mm, in other words, the sum of the widths of the first L-shaped cavity 471 and the second L-shaped cavity 472 is greater than 80 mm.

[0064] The convex rib 431 is protrudingly provided at the edge of one side of the first L-shaped cavity 471 of the first housing 43, and the receiving groove 441 is recessedly provided at the edge of one side of the second L-shaped cavity 472 of the second housing 44. A fixing column 433 is provided at the top of the first housing 43 near the convex rib 431, and a fixing column 433 is also provided at the top of the second housing 44 near the receiving groove 441. One of the two fixing columns 433 is a screw hole, and the other is a screw through hole, so that the first housing 43 and the second housing 44 can be fixed by screws passing through the two fixing columns 433.

[0065] The purposes of setting the fixing column 433 inside the first cover shell 43 and the second cover shell 44 are: 1. Fixing the first cover shell 43 and the second cover shell 44 inside to prevent screws from being inserted from the outside and affecting the waterproof effect of the power head 3; 2. Both fixing columns 433 are wrapped by the upper cover shell 45, making the appearance of the power head 3 more beautiful.

[0066] The housing assembly 40 also contains a control board 48 placed near the battery pack for controlling the motor. Two control boards 48 are provided to detect and control the self-propelled motor (not shown) and the main knife motor 32 respectively. One end of the air inlet cavity 42 is connected to the air inlet 41, and the other end extends to the corresponding control board 48 to guide the cooling airflow entering from the air inlet 41 to the control board 48 to cool and dissipate the control board 48.

[0067] In order to enhance the cooling effect, the control board 48 is provided with a heat sink 481, and the other end of the air inlet cavity 42 is arranged close to the heat sink 481. In other words, the air inlet cavity 42 is as close to the heat sink 481 as possible to ensure that the heat sink 481 is fully cooled. Since there are two air inlets 41 and two air inlet cavities 42, two air inlets are formed, which can cool the control board 48 and the heat sink 481 located on the left and right sides of the rear end of the battery compartment 50 respectively.

[0068] The motor 32 is located below the control board 48. When the motor 32 is started, the fan 33 rotates and drives the cooling airflow at the control board 48 into the interior of the motor 32, so that the heat generated by the control board 48, the motor 32 and the battery pack is blown along the internal rotor air gap of the motor 32 to the bottom of the motor base 31 and discharged from the air outlet 311.

[0069] Heat dissipation process: the motor 32 starts, the fan 33 rotates and generates suction, and the external cooling airflow enters from the air inlet 41 under the suction of the fan 33 and flows into the power head 3 along the air inlet cavity 42. The cooling airflow entering the power head 3 passes through the control board 48 and the heat sink 481 first, and then flows downward to the vent 341 of the wind condenser 34, and enters the motor 32 from the vent 341, and finally flows out from the air outlet 311 at the bottom of the motor seat 31. During the flow of the cooling airflow, the heat inside the battery pack, the control board 48 and the motor 32 will be taken away, so that the power head 3 can work at a relatively stable temperature.

[0070] In summary, the lawn mower 100 of the present invention is configured such that the motor base 31 is closed at the bottom and the air outlet 311 is provided on the side, so that when the bottom of the lawn mower 100 is cleaned, water can be prevented from entering the motor base 31 through the air outlet 311. Combined with the design of some waterproof structures (such as waterproof ribs 312, annular grooves 12, water leakage holes 121, grooves 314, openings 3140, wool felt 317, convex ribs 431, receiving grooves 441, first water retaining extensions 432, second water retaining extensions 442, and third water retaining extensions 451), the waterproof performance of the lawn mower 100 of the present invention is optimal.

[0071] In addition, by setting a grip cavity 47 at the top rear end of the power head 3, the grip cavity 47 can be used as a rear handle, so that when carrying the lawn mower 100, there is no need to add additional handle parts, and the front handle 7 and the rear handle 47 can be directly held by the left and right hands respectively for carrying.

[0072] Furthermore, by arranging an air inlet 41 and an air inlet cavity 42 at the top rear end of the power head 3, an external cooling airflow can enter the power head 3 from the air inlet 41 and the air inlet cavity 42, and take away the heat inside the battery pack, the control board 48 and the motor 32, so that the heat dissipation performance of the lawn mower 100 of the present invention is optimized.

[0073] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A power head, comprising a motor assembly, an energy device and a housing assembly covering the outside of the motor assembly and the energy device, wherein the motor assembly comprises a motor seat and a motor fixed on the motor seat, and the housing assembly comprises a cover assembled with the motor seat, characterized in that: The top of the cover shell is provided with an air inlet inclined toward the rear and downward and an air inlet cavity connected to the air inlet, the air inlet and the air inlet cavity are respectively provided with two and symmetrically arranged on the left and right sides of the cover shell, the air inlet cavity comprises a first ramp arranged close to the air inlet, a second ramp arranged away from the air inlet, and guide plates arranged beside the first ramp and the second ramp, the first ramp is downslope toward the air inlet, and the second ramp is upslope toward the air inlet, the first ramp, the second ramp, the guide plates and the inner side wall of the cover shell together surround the air inlet cavity into a U-shaped structure with an upper opening, the cover shell covers the top of the air inlet cavity to form a closed airflow channel, the bottom of the motor base is closed, and the side is provided with an air outlet communicating with the outside, the cooling air enters from the air inlet and flows into the interior of the motor along the airflow channel, and then flows out from the air outlet; There is also a control panel near the energy device in the housing. One end of the air inlet cavity is connected to the air inlet, and the other end extends to the control panel to guide the cooling airflow entering from the air inlet to the control panel.

2. The power head according to claim 1, characterized in that: The control board is provided with a heat sink, and the other end of the air inlet cavity is arranged close to the heat sink.

3. The power head according to claim 1, characterized in that: The motor is located below the control board. The motor assembly further includes a fan disposed on the top of the motor. When the motor is started, the fan rotates and drives the cooling airflow at the control board into the interior of the motor.

4. The power head according to claim 3, characterized in that: The motor assembly also includes a wind collecting cover covering the outside of the motor and the fan, and a vent is provided on the top of the wind collecting cover to drive the cooling air flow at the control panel into the interior of the motor through the vent when the fan rotates.

5. The power head according to claim 3, characterized in that: At least two air outlets are provided to discharge air in different directions; an air guide rib is provided at the air outlet of the motor base, and the air guide rib is deflected and the deflection direction is tangent to the rotation direction of the cooling airflow driven by the fan, so that the airflow direction at the air outlet is consistent with the rotation direction of the fan.

6. The power head according to claim 5, characterized in that: When the rotation direction of the cooling airflow driven by the fan is clockwise, the deflection direction of the air guide rib is deflected to the left relative to the rotation direction of the cooling airflow.

7. The power head according to claim 1, characterized in that: The cover shell includes a first cover shell and a second cover shell that are assembled and fixed to each other, and an upper cover shell that covers the first cover shell and the second cover shell. The first cover shell and the second cover shell are both provided with the air inlet and the air inlet cavity, and the air inlet of the first cover shell and the air inlet of the second cover shell are symmetrical with respect to the center line of the power head, and the air inlet cavity of the first cover shell and the air inlet cavity of the second cover shell are also symmetrical with respect to the center line of the power head. The air flow channel is formed by the air inlet cavity and the upper cover shell.

8. A lawn mower, comprising a main body, a push rod extending upward and backward from the main body, and a power head mounted on the main body, characterized in that: The power head is the power head described in any one of claims 1 to 7, and the air inlet on the power head is arranged close to the push rod.

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