Pneumatic lawn mower

Abstract

The present invention discloses a pneumatic lawn mower, which has a simple structure, large torque, high speed, high transmission efficiency, low energy consumption, and is environmentally friendly by connecting a gas power device to a cutting device. The exhaust is a decompressed gas, the working noise is low, and there is no tail gas pollution. The gas power device used in the pneumatic lawn mower includes an outer ring and a core body. At least one-step secondary flow channel is provided between the nozzle and the discharge port on the outer ring surface of the core body. The gas enters from the air inlet channel, is ejected step by step through the nozzle of the core body and the secondary flow channel, and acts on at least two driving recesses on the circumference of the outer ring, generating thrust on these driving recesses to drive the outer ring to rotate and do work, thereby realizing power output. Finally, the gas is discharged through the discharge port of the core body through the exhaust channel.

Description

Technical Field

[0001] The invention discloses a pneumatic lawn mower, which belongs to the technical field of mechanical devices for gardening and agriculture according to the International Patent Classification (IPC). Background Art

[0002] In the process of lawn maintenance in garden agriculture, lawn mowers are essential equipment. Lawn mowers can be divided into: non-powered push type, walk-behind type, riding type and mounted type according to the operation mode. Among them, powered walk-behind lawn mowers or riding lawn mowers are mostly used in the maintenance of large areas of lawn.

[0003] Among them, in order to provide driving power for the lawn mower, the existing lawn mowers are mostly equipped with gasoline engines. Compared with new energy lawn mowers, gasoline engines have the advantages of compact structure, high efficiency and reliability, and are more difficult to replace.

[0004] But the maintenance of gasoline engines is complicated: for example, starting difficulties are mostly related to gasoline, oil, and electricity. First, consider whether the spark discharge effect of the spark plug is not ideal. If so, adjust the gap of the spark plug or replace it with a new one; second, consider whether the ignition is incorrect due to the magneto. If this is the reason, readjust the engine; finally, consider whether the engine is difficult to start due to the use of substandard gasoline or gasoline that is not pure enough. If this is the case, then replace the gasoline. In addition, consider whether the air filter is blocked, causing the difficulty in air intake. If so, clean the air filter.

[0005] At the same time, with the rapid development of the economy and the improvement of people's living standards, people's requirements for the environment are getting higher and higher. Gasoline-powered lawn mowers have greater engine noise and engine exhaust pollution during lawn maintenance.

[0006] Therefore, there is an urgent need to provide a lawn mower with little environmental pollution, compact structure, high efficiency and reliability. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention provides a pneumatic lawn mower, which uses a gas power device as the power device of the lawn mower, and has a multi-stage flow channel circumferentially arranged on the core of the gas power device, so that the energy of the gas is utilized multiple times, and the core drives the rotating outer ring to achieve power output; the pneumatic lawn mower has the advantages of compact structure, large torque, high speed, high transmission efficiency, energy saving and environmental protection.

[0008] To achieve the above object, the present invention is achieved through the following technical solutions:

[0009] A pneumatic lawn mower comprises a frame, on which a cutting device and a power device are arranged, the power device is drivingly connected to the cutting device; the power device is a gas power device, which comprises:

[0010] An outer ring, whose inner ring surface is provided with a plurality of driving recesses in the circumferential direction;

[0011] A core body is coaxially arranged in the outer ring and can rotate relative to the outer ring, and the outer ring surface of the core body is provided with at least one nozzle, at least one discharge port, and at least one flushing channel located between the nozzle and the discharge port;

[0012] at least one air inlet passage connected to at least one nozzle; and

[0013] at least one exhaust passage connected to at least one exhaust port;

[0014] The gas enters from the air inlet channel, is ejected step by step through the nozzle of the core body and the secondary flow channel, and acts on at least two driving recesses on the circumference of the outer ring, generating thrust for these driving recesses to drive the outer ring to rotate and do work, thereby realizing power output. Finally, the gas is discharged through the exhaust channel through the exhaust port of the core body.

[0015] Furthermore, at least one air inlet channel, at least one nozzle, at least two driving recesses, at least one primary flow channel, at least one discharge port and at least one exhaust channel form an independent working unit, and the gas power device includes at least one independent working unit.

[0016] Furthermore, the nozzles and secondary flow channels on the core body are connected to the driving recesses corresponding to the outer ring. The secondary flow channels are arranged alternately and connected in sequence with the corresponding driving recesses. The secondary flow channels are arranged circumferentially along the core body or the outer ring.

[0017] Further, an intake passage and an exhaust passage are formed in the core.

[0018] Furthermore, the core includes:

[0019] An air inlet passage, which forms a nozzle on the peripheral surface of the core body, and whose direction is an arc line extending from the middle to the outside, and the nozzle is connected with the driving concave portion corresponding to the outer ring to form a first-stage flow channel;

[0020] The secondary flow channel is an arc line extending from the edge of the core body inward and then bending to the edge. Each secondary flow channel is connected with the front and rear driving recesses corresponding to the outer ring, forming N-step flow channels along the circumference of the core body, where N is a natural number ≥ 2;

[0021] Each step of the flow channel cooperates with the corresponding driving recess of the outer ring to form a multi-step stroke structure with decreasing gas energy.

[0022] Furthermore, the secondary flow channel includes a return channel and a communicating stroke channel, the return channel is communicated with a driving recess corresponding to the outer ring, and the stroke channel is communicated with another driving recess.

[0023] Furthermore, the direction of the core air inlet channel is a logarithmic spiral extending from the middle to the outside, the pole of the logarithmic spiral is set on the central axis of the core, and the direction angle of the logarithmic spiral is 15°-45°.

[0024] Furthermore, an air inlet channel is provided on the core body, and its direction is a logarithmic spiral extending from the middle to the outside, and the direction of the stroke channel of the secondary flow channel is a logarithmic spiral. The direction of the logarithmic spiral of the stroke channel of the secondary flow channel is roughly the same as the direction of the logarithmic spiral of the air inlet channel.

[0025] Furthermore, the gas power device also includes a shaft, and the outer ring and the core body are coaxially arranged on the shaft.

[0026] Furthermore, the gas power device also includes a shaft, the outer ring is coaxially arranged on the shaft with the core body, and the shaft is provided with inlet and outlet shaft passages which are respectively connected to the inlet channel and the exhaust channel of the core body.

[0027] The air inlet and outlet shaft passages in the shaft form an air inlet and an air outlet, and the air inlet and outlet shaft passages are non-connected structures.

[0028] Furthermore, the outer ring is matched with the shaft through the side plates to form a closed space, and the core body is arranged in the closed space and is connected and fixed to the shaft.

[0029] Furthermore, the air inlet channel, the nozzle, the driving recess, the secondary flow channel, the exhaust port and the exhaust channel in the independent working unit constitute a gas flow path.

[0030] Furthermore, the gas power device includes more than two independent working units to form a multi-stage driving structure, and is arranged along the circumference of the core or the outer ring.

[0031] Furthermore, more than two driving recesses are arranged on the inner ring surface of the outer ring, and each driving recess has a contour bottom surface and a driving surface. The contour line of the contour bottom surface is a logarithmic spiral line, and its pole is arranged at the center of the core body.

[0032] Furthermore, a storage tank for supplying gas to the gas power device is also provided on the frame; the storage tank is connected to the air inlet passage through a valve body assembly pipeline.

[0033] Furthermore, it also includes first and second transmission devices, and the outer ring of the gas power device is transmission-connected to the cutting device through the first transmission device;

[0034] The frame is also provided with a traveling device, and the outer ring of the gas power device is transmission-connected with the traveling device through the second transmission device.

[0035] The pneumatic lawn mower of the present invention has a simple structure, large torque, high rotation speed, high transmission efficiency, low energy consumption, and is environmentally friendly by connecting a gas power device to a cutting device. The exhaust gas is decompressed gas, the working noise is low, and there is no tail gas pollution.

[0036] The gas power device of the present invention also has the following beneficial effects:

[0037] 1. The core body of the present invention is provided with a multi-stage flow channel, that is, the air inlet channel is used as the first stage flow channel, and each secondary flow channel is used as the second, third, fourth... stage flow channel. The gas acts on the driving recess of the outer ring from the first stage flow channel, and the driving recess is connected to the second stage flow channel. Then, it returns to the second stage flow channel and acts on another driving recess of the outer ring, and so on, until the gas is discharged from the exhaust channel. The whole process is carried out in the forward direction of the outer ring rotation direction, with large torque, high transmission efficiency, high gas utilization rate, and the output torque further increases with the increase of the rotation speed; it is used to drive the cutting device to efficiently trim the lawn.

[0038] 2. The flow channels arranged circumferentially on the core of the present invention effectively reduce the volume of the overall device, and can be used in conjunction with the walking device of the lawn mower to output power. At the same time, the more inlet flow channels are arranged on the core, the lower the overall weight is, which further improves the output speed and efficiency of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 The figure shows a schematic diagram of the structure of the pneumatic lawn mower according to the first embodiment of the present invention;

[0040] Figure 2 The figure shows a schematic diagram of the structure of the pneumatic lawn mower according to the first embodiment of the present invention at angle 2;

[0041] Figure 3 It is a schematic diagram of the gas power device of the first embodiment of the present invention.

[0042] Figure 4 It is a side view along axis A of the gas power device of the first embodiment of the present invention.

[0043] Figure 5 It is a side view of the gas power device in the first embodiment of the present invention along the axis B.

[0044] Figure 6 It is a radial cross-sectional view of the gas power device according to the first embodiment of the present invention.

[0045] Figure 7 This is another layout diagram of the gas power device according to the first embodiment of the present invention.

[0046] Figure 8 It is a schematic diagram of the gas power device of the pneumatic lawn mower according to the second embodiment of the present invention.

[0047] Fig. 9 It is a side view of the gas power device of the second embodiment of the present invention along the axis C.

[0048] Fig.10 It is a side view of the gas power device in the second embodiment of the present invention along the axis D.

[0049] Fig.11 It is a radial cross-sectional view of the gas power device according to the second embodiment of the present invention. DETAILED DESCRIPTION

[0050] The present invention will be further described below in conjunction with the accompanying drawings:

[0051] Embodiment 1:

[0052] Combination Figure 1 and Figure 2 As shown, this embodiment provides a pneumatic lawn mower, further, a riding lawn mower, which includes a frame 5, and a cutting device 6 and a power device 9 are respectively installed below and above the frame 5. The output unit of the power device 9 is drivingly connected to the cutting device 6 to provide cutting power.

[0053] In this embodiment, a traveling device is respectively provided at the front and rear ends of the frame 5. Preferably, a steering traveling device with a steering wheel is provided at the front end of the frame 5, and a driving traveling device 7 with a differential is provided at the rear end of the frame 5; wherein the power device 9 is connected to the rotating blade of the cutting device 6 through a first pulley group 91 as a first transmission device, and the power device 9 is also connected to the driving traveling device 7 through a second pulley group 92 as a second transmission device.

[0054] In this embodiment, the power device 9 is a gas power device. Furthermore, the frame 5 is also provided with a storage tank 8 for supplying gas to the gas power device 9; the storage tank is connected to the gas power device 9 through a valve body assembly pipeline; the storage tank 8 is preferably a high-pressure gas storage tank, a Dewar tank or a gas cylinder.

[0055] See also Figures 3 to 6 The gas power device comprises an outer ring 1, whose inner ring surface is provided with a plurality of driving recesses 11 in the circumferential direction; a core body 3, which is coaxially arranged in the outer ring 1 and can rotate relative to the outer ring, and the outer ring surface of the core body 3 is provided with at least one nozzle 301, at least one discharge port 302, and at least one primary flow channel 300 located between the nozzle and the discharge port;

[0056] At least one air inlet passage 31 connected to at least one nozzle 301; and

[0057] at least one exhaust passage 310 connected to at least one exhaust port 302;

[0058] The compressed gas of the storage tank 8 enters from the air inlet channel 31, and is ejected step by step through the nozzle 301 of the core body 3 and the secondary flushing channel 300, acting on at least two driving recesses 11 on the circumference of the outer ring 1, generating thrust on these driving recesses 11 to drive the outer ring 1 to rotate and do work, realizing continuous power output, and finally, the gas is discharged through the exhaust channel through the exhaust port of the core body 3. The gas power device also includes a shaft 2, and the outer ring 1 and the core body 3 are coaxially arranged on the shaft 2.

[0059] like Figure 6 As shown, the air inlet channel 31 and the exhaust channel 310 are formed in the core body 3, and the nozzle 301 and the secondary flow channel 300 on the core body 3 are connected with the driving recess 11 corresponding to the outer ring 1, wherein the secondary flow channel 300 and the corresponding driving recess 11 are arranged alternately and connected in sequence, and the secondary flow channel 300 is arranged along the circumference of the core body or the outer ring.

[0060] like Figure 6 The core 3 includes: an air inlet channel 31, which forms a nozzle 31 on the peripheral surface of the core, and its direction is an arc line extending from the middle to the outside, and the nozzle 301 is connected with the driving recess 11 corresponding to the outer ring to form a first-stage flow channel;

[0061] The secondary flushing channel 300 is an arc line extending from the edge of the core 3 inward and then bending to the edge. Each flushing channel 300 is connected with the front and rear driving recesses 11 corresponding to the outer ring 1, forming N-stage flow channels along the circumference of the core, where N is a natural number ≥ 2. It should be noted that if it is a 2-stage flow channel, it includes the 1st stage flow channel (inlet channel) and the 2nd stage flow channel (primary flushing channel); if it is a 3-stage flow channel, it includes the 1st stage flow channel (inlet channel), the 2nd stage flow channel (primary flushing channel), the 3rd stage flow channel (another secondary flushing channel), ...

[0062] Each step of the flow channel cooperates with the corresponding driving recess of the outer ring to form a multi-step stroke structure with decreasing gas energy.

[0063] The gas power device can be designed according to the load requirements, in which the core 3 can be set to a 2-stage flow channel, a 3-stage flow channel, or more stages of intake flow channels. Each stage cycle performs work, fully utilizes energy, and maximizes the use efficiency to meet the output torque and speed requirements.

[0064] like Figure 7 Schematic diagram of a 4-stage flow channel. After the compressed gas enters from the 1st-stage flow channel 311, it passes through the 2nd, 3rd, and 4th-stage flow channels 312, 313, and 314, and is ejected to act on the corresponding driving recess 11, and finally is output through the exhaust flow channel 310; Figure 6 This is a schematic diagram of the 5-stage intake air duct. The working process is the same as Figure 7 The schematic is similar. Figure 7 The secondary flow channel 300 includes a return channel and a connected stroke channel, such as Figure 7The return path 3131 and the connected stroke path 3132 in the third-stage flow channel, the return path 3131 is connected to the driving recess corresponding to the outer ring, and the stroke path 3132 is connected to another driving recess.

[0065] See also Figure 3 The gas power device also includes a shaft 2, the outer ring 1 is coaxially arranged on the shaft 2 with the core 3, and the shaft 2 is provided with inlet and outlet shaft channels 21, 210 respectively connected to the inlet channel 31 and the exhaust channel 310 of the core 3. The inlet and outlet shaft channels in the shaft form an inlet and an outlet, and the inlet and outlet shaft channels are non-connected structures. The outer ring 1 is matched with the shaft 2 through the side plates 41, 42 to form a closed space, and the core 3 is arranged in the closed space and connected and fixed to the shaft 2. In the present invention, the core 3 is provided with at least two steps of flow channels, each step of the flow channel is connected to the driving recess corresponding to the outer ring, and finally the gas is discharged from the exhaust flow channel.

[0066] See also Figure 3 In the present invention, the core body 3 can be formed by the cooperation of a left core body and a right core body, and the cooperation surfaces of the left core body and the right core body are provided with an air intake channel 31 and an exhaust channel 310. The core body 3 can also be integrally cast.

[0067] See also Figure 3 , Figure 6 This embodiment is a primary drive structure. An air channel is arranged circumferentially on the core 3 to form a primary drive structure. The air channel is also called an independent working unit. An air inlet channel 31, a nozzle 301, at least two driving recesses 11, at least one primary flow channel 300, a discharge port 302 and an exhaust channel 310 on the core 3 and the outer ring 1 form an independent working unit. The gas power device includes at least one independent working unit. The air inlet channel 31, the nozzle 301, the driving recess 11, the secondary flow channel 300, the discharge port 302 and the exhaust channel 310 in the independent working unit constitute a gas flow path.

[0068] See also Figure 3 , Figure 6 or Figure 7 In the present invention, more than two driving recesses 11 are arranged on the inner ring surface of the outer ring 1, each driving recess has a contour bottom surface 111 and a driving surface 112, the contour line of the contour bottom surface 111 can be a common arc line or a spiral line, when the contour line of the contour bottom surface is a logarithmic spiral line, its pole is set on the axis, each driving recess 11 is also connected with the adjacent step flow channel so that the gas entering the previous step flow channel is discharged from the next step flow channel.

[0069] In the present invention, the direction of the air inlet channel of the core body 3, namely the first-stage flow channel, can be a common arc line or a spiral line, and the direction of each secondary flow channel, namely the stroke channel in the Nth-stage flow channel, can also be a common arc line or a spiral line.

[0070] like Figure 6 and Figure 7 The core body 3 of the present invention is provided with an air inlet channel 31, which runs in a logarithmic spiral extending from the middle to the outside. The stroke channel of the secondary flow channel 300 runs in a logarithmic spiral, and the logarithmic spiral of the stroke channel of the secondary flow channel runs in a direction substantially the same as the logarithmic spiral of the air inlet channel. The air inlet channel of the core body 3 runs in a logarithmic spiral extending from the middle to the outside, and the pole of the logarithmic spiral is set on the central axis of the core body. The logarithmic spiral runs in an angle of 15°-45°. The smaller the angle, the longer the flow channel and the more the loss. The larger the angle, the smaller the tangential component of the driving outer ring.

[0071] See also Figure 3 , Figure 4 and Figure 5 In the present invention, the inlet and outlet shaft channels 21, 210 in the shaft 2 form an inlet and an outlet, and the inlet and outlet shaft channels are non-connected structures. The inlet and outlet of the shaft can be set at one end or both ends of the shaft, the inlet shaft channel 21 is connected to the inlet channel 31 of the core body, and the shaft outlet extends axially to form the outlet shaft channel 210, which is connected to the exhaust channel 310 of the core body.

[0072] The gas power device involved in this application refers to a device that can convert gas energy into mechanical rotation, wherein the device may include other components in addition to the necessary outer ring, core body and its corresponding recessed structure or flow channel structure design; for example, it may include a housing and a sealing structure that provide external protection, or a coupling that provides torque transmission. The outer ring may have different specific forms according to different mechanical rotation output modes, such as an outer toothed structure formed on the outer side of the outer ring to facilitate the output of kinetic energy through gear transmission; another example is that the outer ring has a belt groove to output kinetic energy through belt transmission; another example is that the outer ring has a mounting flange to facilitate the installation of a coupling to output kinetic energy; and so on. The core body and the outer ring are made of hard materials, not limited to metals, metal alloys, plastics, and composite materials. The processing methods of the recessed structure or flow channel structure of the core body and the outer ring can be realized by all known production means, including but not limited to die casting, forging, extrusion, 3D printing, and so on. The air pressure input to the power device may be generated by a compressor (such as an air pressure pump), a container of compressed fluid (such as a high-pressure gas cylinder), etc. In this embodiment, the outer ring 1 has two sets of belt grooves, which are respectively connected to the driving walking device 7 and the cutting device 6 of the pneumatic lawn mower through two sets of belts.

[0073] It can be understood that the lawn mower of this embodiment is a riding lawn mower. In other specific embodiments, a hand-held lightweight lawn mower can be formed by providing a hand-held handle on the frame; or, a wheel set without driving force can be provided on the frame, and a hand handle can be extended upward from the frame to form a hand-pushed lawn mower.

[0074] Figure 3 and Figure 6 It should be noted that the air inlet channel 31 and the exhaust channel 310 of the core body and the air inlet shaft channel 21 and the air outlet shaft channel 210 do not correspond to each other according to the drawing rules, but for the sake of illustration, Figure 3 The air inlet channel and the exhaust channel of the core body refer to the air inlet channel and the exhaust channel. Figure 8 and Fig.11 A similar schematic diagram is shown here.

[0075] Example 2: Please refer to Figures 8 to 11 The pneumatic lawn mower of this embodiment is basically the same as that of embodiment 1, and the main differences are as follows:

[0076] The gas power device includes two independent working units to form a two-stage drive structure, that is, two air channels are arranged circumferentially on the core 3, each air channel includes an intake channel 31 of more than one order and a secondary flow channel 300 and an exhaust flow channel arranged circumferentially along the core 3. The gas power device comprises an outer ring 1, whose inner ring surface is provided with a plurality of driving recesses 11 on the circumference; a core body 3, which is coaxially arranged in the outer ring 1 and can rotate relative to the outer ring, and the outer ring surface of the core body is provided with two groups of nozzles and exhaust ports, and at least one primary flow channel is provided between each group of nozzles and exhaust ports; the core body is provided with two air inlet channels 31, 32, which correspond to the connected nozzles; and two exhaust channels 310, 320, which correspond to the connected exhaust ports; two streams of gas enter from the two air inlet channels of the core body respectively, and are ejected step by step through the nozzles of the core body 3 and the secondary flow channel 300, acting on the corresponding driving recesses 11 on the circumference of the outer ring, generating thrust on these driving recesses to drive the outer ring 1 to rotate and do work, realizing power output, and finally, the gas is discharged through the exhaust port of the core body through the exhaust channel. The above-mentioned one air inlet channel, one nozzle, a corresponding number of driving recesses and corresponding secondary flow channels, exhaust ports and one exhaust channel form an independent work unit.

[0077] The gas power device also includes a shaft 2, and the outer ring 1 is coaxially arranged on the shaft with the core 3. The shaft 2 is provided with air inlet shafts 21, 22 and air outlet shafts 210, 220 which are respectively connected to the air inlet channels 31, 32 and the air exhaust channels 310, 320 of the core. The shaft 2 is provided with two air inlets and two air outlets corresponding to the air channels; the compressed gas enters from the two air inlets of the shaft 2, is ejected through the air inlet channel of the core 3, and acts on the driving recess 11 of the outer ring 1, generating thrust to drive the outer ring 1 to rotate and do work, and finally the compressed gas returns to the corresponding air outlet through the exhaust channel of the core 3, realizing the continuous output of power. The other structures are the same as those in Example 1 and will not be repeated.

[0078] Embodiment 3: The pneumatic lawn mower of this embodiment is basically the same as that of Embodiment 1, with the main differences being:

[0079] The gas power device of the present invention includes 4 or more independent working units to form a multi-stage driving structure. Three or more air channels are arranged circumferentially on the core body. Each air channel includes an intake channel and a secondary flow channel of more than one order and an exhaust flow channel arranged circumferentially along the core body. The intake channel and the exhaust channel are arranged on the mating surfaces of the left and right core bodies. The shaft is provided with intake shaft channels and exhaust shaft channels corresponding to the number of air channels. The compressed gas enters from the intake shaft channel of the shaft, is ejected through the intake flow channel of the core body, and acts on the driving recess of the outer ring, pushing the outer ring to rotate and do work, realizing continuous power output, and finally the compressed gas returns to the corresponding exhaust shaft channel through the exhaust flow channels of the core body. The other structures are the same as those in Example 1.

[0080] Those skilled in the art should understand that in other specific embodiments, the pneumatic lawn mower may not be provided with a storage tank, and the air intake channel 31 of the gas power device may be connected to the high-pressure gas source through an air guide hose, and the technical effect of the present invention may also be achieved. The above records are only embodiments of the technical content of this creation. Any modification and changes made by a person familiar with this art using this creation are within the patent scope claimed by this creation, and are not limited to those disclosed in the embodiments.

Claims

1. A pneumatic lawn mower, comprising a frame, on which a cutting device and a power device are provided, wherein the power device is drivingly connected to the cutting device; characterized in that: The power device is a gas power device, which includes: An outer ring, whose inner ring surface is provided with a plurality of driving recesses in the circumferential direction; A core body is coaxially arranged in the outer ring and can rotate relative to the outer ring, and the outer ring surface of the core body is provided with at least one nozzle, at least one discharge port, and at least one flushing channel located between the nozzle and the discharge port; at least one air inlet passage connected to at least one nozzle; and at least one exhaust passage connected to at least one exhaust port; The gas enters from the air inlet channel, is ejected step by step through the nozzle of the core body and the secondary flow channel, and acts on at least two driving recesses on the circumference of the outer ring, generating thrust for these driving recesses to drive the outer ring to rotate and do work, thereby realizing power output. Finally, the gas is discharged through the exhaust channel through the exhaust port of the core body.

2. The pneumatic lawn mower according to claim 1, characterized in that: At least one air inlet channel, at least one nozzle, at least two driving recesses, at least one primary flow channel, at least one discharge port and at least one exhaust channel form an independent working unit. The gas power device includes at least one independent working unit.

3. The pneumatic lawn mower according to claim 1, characterized in that: The air inlet channel and the air exhaust channel are formed in the core body. The nozzle and the secondary flow channel on the core body are connected with the driving recess corresponding to the outer ring. The secondary flow channel is arranged along the circumference of the core body or the outer ring.

4. The pneumatic lawn mower according to claim 3, characterized in that: The core includes An air inlet passage, which forms a nozzle on the peripheral surface of the core body, and whose direction is an arc line extending from the middle to the outside, and the nozzle is connected with the driving concave portion corresponding to the outer ring to form a first-stage flow channel; The secondary flow channel is an arc line extending from the edge of the core body inward and then bending to the edge. Each secondary flow channel is connected with the front and rear driving recesses corresponding to the outer ring, forming N-step flow channels along the circumference of the core body, where N is a natural number ≥ 2; Each step of the flow channel cooperates with the corresponding driving recess of the outer ring to form a multi-step stroke structure with decreasing gas energy.

5. The pneumatic lawn mower according to claim 3, characterized in that: The direction of the core air inlet channel is a logarithmic spiral extending from the middle to the outside, the pole of the logarithmic spiral is set on the central axis of the core, and the direction angle of the logarithmic spiral is 15°-45°.

6. The pneumatic lawn mower according to claim 1, characterized in that: The gas power device also includes a shaft, on which the outer ring is coaxially arranged with the core body, and on which an inlet and an outlet shaft passage are opened, which are respectively connected to an inlet passage and an outlet passage of the core body.

7. The pneumatic lawn mower according to claim 2, characterized in that: The gas power device comprises more than two independent working units to form a multi-stage driving structure, and the units are arranged along the circumference of the core or the outer ring.

8. The pneumatic lawn mower according to any one of claims 1 to 7, characterized in that: More than two driving recesses are arranged on the inner ring surface of the outer ring, each driving recess has a contour bottom surface and a driving surface, the contour line of the contour bottom surface is a logarithmic spiral line, and its pole is arranged at the center of the core body.

9. The pneumatic lawn mower according to any one of claims 1 to 7, characterized in that: The frame is also provided with a storage tank for supplying gas to the gas power device; the storage tank is connected to the air inlet passage through a valve body assembly pipeline.

10. The pneumatic lawn mower according to any one of claims 1 to 7, characterized in that: It also includes a first and a second transmission device, and the outer ring of the gas power device is transmission-connected to the cutting device through the first transmission device; a walking device is also provided on the frame, and the outer ring of the gas power device is transmission-connected to the walking device through the second transmission device.

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