阅读说明：本技术 一种推草机及其控制方法和控制装置 (Grass mower and control method and control device thereof ) 是由 不公告发明人 于 2020-05-13 设计创作，主要内容包括：本发明公开了一种推草机及其控制方法和控制装置,该控制方法具体包括,接收选择指令,选择指令包含草坪草种类,并根据选择指令获取与草坪草种类对应的刀头目标转速；根据刀头目标转速驱动割草刀头以刀头目标转速旋转；接收位移机构的实时移动速度,并判断位移机构的实时移动速度是否小于第一目标速度或大于第二目标速度,其中第一目标速度和第二目标速度与刀头目标转速对应；若是,则生成并发送警报指令,若否,则不发出警报指令。本发明提供的推草机能够根据选择或输入的草坪草种类自动匹配合适的刀头转速,并根据刀头转速得到合适的行进速度,防止用户在不甚了解草坪护理的情况下,使得推草机行进速度不合适导致漏割或效率低下等情况发生。(The invention discloses a grass mower and a control method and a control device thereof, wherein the control method specifically comprises the steps of receiving a selection instruction, wherein the selection instruction comprises lawn grass types, and acquiring a target rotating speed of a cutter head corresponding to the lawn grass types according to the selection instruction; driving the mowing tool bit to rotate at the tool bit target rotating speed according to the tool bit target rotating speed; receiving the real-time moving speed of the displacement mechanism, and judging whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed, wherein the first target speed and the second target speed correspond to the target rotating speed of the cutter head; if yes, generating and sending an alarm instruction, and if not, not sending the alarm instruction. The grass mower provided by the invention can automatically match the proper rotating speed of the cutter head according to the selected or input lawn grass type and obtain the proper advancing speed according to the rotating speed of the cutter head, so that the situations of missed cutting or low efficiency and the like caused by improper advancing speed of the grass mower under the condition that a user does not know about lawn care are prevented.)

1. A control method of a grass mower is characterized in that the grass mower comprises a grass cutting head, a displacement mechanism driving the grass cutting head to move, and a rotating motor (21) driving the grass cutting head to rotate;

the control method comprises the following steps:

s1, receiving a selection instruction, wherein the selection instruction comprises lawn grass types, and acquiring a target rotating speed of a cutter head corresponding to the lawn grass types according to the selection instruction;

s2, driving the mowing tool bit to rotate at the tool bit target rotating speed according to the tool bit target rotating speed;

s3, receiving the real-time moving speed of the displacement mechanism, and judging whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed, wherein the first target speed and the second target speed correspond to the target rotating speed of the cutter head, and the first target speed is smaller than the second target speed;

s4, if yes, generating and sending an alarm instruction, and returning to S3; if not, not sending out an alarm instruction, and returning to S3; until the work of the mower is finished.

2. The method of controlling a lawnmower according to claim 1, wherein in step S3, the first target speed is derived from nL/2 tr and the second target speed is derived from nL/tr, where n is the target rotational speed of the cutter head, L is the length of the cutting edge of the mower head, and r is the radius of rotation of the mower head.

3. The control method of a lawnmower according to claim 1, wherein in step S4, when the real-time moving speed of the displacement mechanism is less than the first target speed, a first alarm instruction is generated and transmitted; and when the real-time moving speed of the displacement mechanism is greater than the second target speed, generating and sending a second alarm instruction.

4. The method of controlling a lawnmower according to any one of claims 1, further comprising, in step S1, obtaining a blade target height corresponding to the type of lawn grass based on the selection instruction;

in step S2, the method further includes driving the mowing head to move to the head target height according to the head target height.

5. The method of controlling a lawnmower according to claim 4, further comprising receiving a real-time blade height signal of the grass cutting blade at step S2.

6. A control device (10) of a grass mower is characterized in that the grass mower comprises a grass cutting head, a displacement mechanism driving the grass cutting head to move, and a rotating motor (21) driving the grass cutting head to rotate; the control device (10) comprises:

the control module (11) is used for receiving a selection instruction and acquiring a target rotating speed of the cutter head corresponding to the lawn grass type according to the selection instruction; driving the mowing tool bit to rotate at the tool bit target rotating speed according to the tool bit target rotating speed; receiving the real-time moving speed of the displacement mechanism, and judging whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed, wherein the first target speed and the second target speed correspond to the target rotating speed of the cutter head, and the first target speed is smaller than the second target speed; if yes, generating and sending an alarm instruction; if not, no alarm instruction is sent;

the receiving module (12) is used for generating the selection instruction according to user operation;

a driving module (13) for driving the rotating motor (21) to enable the mowing head to start rotating at the target rotating speed of the mowing head;

a detection module (14) for detecting the moving speed of the displacement mechanism and sending a moving speed signal of the displacement mechanism to the control module (11);

and the alarm module (15) is used for receiving the alarm instruction and giving an alarm.

7. Control device (10) of a lawnmower according to claim 6, characterized in that the detection module (14) comprises a speed sensor for detecting the real-time movement speed of the displacement mechanism.

8. A control device (10) of a lawnmower according to claim 6, further comprising a lift motor (22) for lifting the mower head; the control module (11) can also obtain a cutter head target height corresponding to the lawn grass type according to the selection instruction, and drive the mowing cutter head to move to the cutter head target height according to the cutter head target height;

the driving module (13) further comprises a lifting motor (22) for driving the mowing head to move to the target mowing head height.

9. Control device (10) of a lawnmower according to claim 8, wherein the detection module (14) is further configured to detect a real-time blade height of the grass cutting blade and send a real-time height signal of the grass cutting blade to the control module (11);

the detection module (14) further comprises a distance sensor for detecting the real-time mower head height of the mowing head.

10. The control device (10) of a lawnmower according to claim 6, wherein the control module (11) derives the first target speed by nL/2 tr and the second target speed by nL/tr, wherein n is the target rotational speed of the cutter head, L is the length of the cutting edge of the grass cutting head, and r is the radius of rotation of the grass cutting head.

11. The control device (10) of a lawnmower according to claim 6, wherein the control module (11) issues a first alarm command when the real-time movement speed of the displacement mechanism is less than the first target speed, and the control module (11) issues a second alarm command when the real-time movement speed of the displacement mechanism is greater than the second target speed.

12. The control device (10) of a lawnmower according to claim 11, wherein the alarm module (15) comprises at least two alarm modes, the alarm unit issuing a first alarm when a first alarm command is received and a second alarm distinct from the first alarm when a second alarm command is received.

13. A grass mower is characterized by comprising a grass cutting head, a displacement mechanism driving the grass cutting head to move, and a rotating motor (21) driving the grass cutting head to rotate; further comprising:

the control device (10) according to any one of claims 6-12;

a power supply unit (31) for supplying power to the lawnmower;

the rotating electrical machine (21) and the control device (10) are respectively coupled to the power supply unit (31).

14. The lawnmower of claim 13, further comprising a lift motor (22) to raise and lower the mower head, the lift motor (22) being coupled to the power unit (31).

15. A lawnmower according to claim 13, further comprising a first switch (32) and a second switch (33), the first switch (32) being provided between the power supply unit (31) and the control module (11), the second switch (33) being provided between the power supply unit (31) and the rotary electric machine (21).

Technical Field

The invention relates to the field of garden machinery, in particular to a grass mower and a control method and a control device thereof.

Background

The grass mower is one of outdoor gardening tools and is used for trimming lawns. Corresponding to different lawn purposes and different lawn grass types, the lawn grass is difficult to cut well at one time under the condition that a user does not know the mowing effect of the grass mower. If the moving speed is too high during mowing, the missed cutting of the lawn is serious, and the user needs to mow twice or even many times; if the moving speed is too slow during mowing, the mowing time is too long, precious time of a user is wasted, and the service life of a battery is also shortened.

Disclosure of Invention

The invention aims to solve the technical problem of providing a grass mower and a control method thereof aiming at the defects of the prior art.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a control method of a grass mower comprises the steps that the grass mower comprises a grass mowing cutter head, a displacement mechanism driving the grass mowing cutter head to move and a rotating motor driving the grass mowing cutter head to rotate;

the control method comprises the following steps:

s1, receiving a selection instruction, wherein the selection instruction comprises lawn grass types, and acquiring a target rotating speed of a cutter head corresponding to the lawn grass types according to the selection instruction;

s2, driving the mowing tool bit to rotate at the tool bit target rotating speed according to the tool bit target rotating speed;

s3, receiving the real-time moving speed of the displacement mechanism, and judging whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed, wherein the first target speed and the second target speed correspond to the target rotating speed of the cutter head, and the first target speed is smaller than the second target speed;

s4, if yes, generating and sending an alarm instruction, and returning to S3; if not, not sending out an alarm instruction, and returning to S3; until the work of the mower is finished.

Preferably, in step S3, the first target speed is derived from nL/2 pi r, and the second target speed is derived from nL/pi r, where n is the target rotation speed of the cutter head, L is the length of the cutting edge of the mowing cutter head, and r is the rotation radius of the mowing cutter head.

Preferably, in step S4, when the real-time moving speed of the displacement mechanism is less than the first target speed, a first alarm instruction is generated and sent; and when the real-time moving speed of the displacement mechanism is greater than the second target speed, generating and sending a second alarm instruction.

Preferably, in step S1, the method further includes obtaining a target height of the cutter head corresponding to the lawn grass type according to the selection instruction;

in step S2, the method further includes driving the mowing head to move to the head target height according to the head target height.

Preferably, step S2 further comprises receiving a real-time mower head height signal of the mowing head.

The invention also provides a control device of the grass mower, wherein the grass mower comprises a grass cutting head, a displacement mechanism driving the grass cutting head to move and a rotating motor driving the grass cutting head to rotate; the control device includes:

the control module is used for receiving a selection instruction and acquiring a target rotating speed of the cutter head corresponding to the lawn grass type according to the selection instruction; driving the mowing tool bit to rotate at the tool bit target rotating speed according to the tool bit target rotating speed; receiving the real-time moving speed of the displacement mechanism, and judging whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed, wherein the first target speed and the second target speed correspond to the target rotating speed of the cutter head, and the first target speed is smaller than the second target speed; if yes, generating and sending an alarm instruction; if not, no alarm instruction is sent;

the receiving module is used for generating the selection instruction according to user operation;

the driving module is used for driving the rotating motor to enable the mowing tool bit to start rotating at the tool bit target rotating speed;

the detection module is used for detecting the moving speed of the displacement mechanism and sending a moving speed signal of the displacement mechanism to the control module;

and the alarm module is used for receiving the alarm instruction and sending an alarm.

Preferably, the detection module comprises a speed sensor for detecting the real-time movement speed of the displacement mechanism.

Preferably, the grass mower further comprises a lifting motor for driving the grass cutting head to lift; the control module can also acquire a cutter head target height corresponding to the lawn grass type according to the selection instruction and drive the mowing cutter head to move to the cutter head target height according to the cutter head target height;

the driving module further drives the lifting motor to move the mowing head to the target height of the mowing head.

Preferably, the detection module is further configured to detect a real-time cutter head height of the mowing cutter head, and send a real-time height signal of the mowing cutter head to the control module;

the detection module further comprises a distance sensor for detecting the height of the real-time cutter head of the mowing cutter head.

Preferably, the control module obtains the first target speed through nL/2 pi r, and obtains the second target speed through nL/pi r, wherein n is the target rotating speed of the cutter head, L is the cutting edge length of the mowing cutter head, and r is the rotating radius of the mowing cutter head.

Preferably, the control module issues a first alarm instruction when the real-time moving speed of the displacement mechanism is less than the first target speed, and issues a second alarm instruction when the real-time moving speed of the displacement mechanism is greater than the second target speed.

Preferably, the alarm module includes at least two alarm modes, and the alarm unit issues a first alarm when receiving a first alarm instruction, and issues a second alarm different from the first alarm when receiving a second alarm instruction.

The invention also provides a grass mower which comprises a grass cutting head, a displacement mechanism driving the grass cutting head to move and a rotating motor driving the grass cutting head to rotate; further comprising:

any one of the above control devices;

a power supply unit for supplying power to the mower;

the rotating motor and the control device are respectively coupled with the power supply unit.

Preferably, the lawn mower further comprises a lifting motor for driving the mowing head to lift, and the lifting motor is coupled with the power supply unit.

Preferably, the lawn mower further comprises a first switch and a second switch, the first switch is arranged between the power supply unit and the control module, and the second switch is arranged between the power supply unit and the rotating motor.

The invention has the following beneficial effects: the grass mower provided by the invention can automatically match the proper rotating speed of the cutter head according to the selected or input lawn grass type and obtain the proper advancing speed according to the rotating speed of the cutter head, so that the situations of missed cutting or low efficiency and the like caused by improper advancing speed of the grass mower under the condition that a user does not know about lawn care are prevented.

Drawings

The invention will be further described with reference to the accompanying drawings and examples, in which:

FIG. 1 is a flowchart of a control method of the first embodiment of the present invention;

FIG. 2 is a schematic structural view of a control device according to a first embodiment of the present invention;

FIG. 3 is a flowchart of a control method of the second embodiment of the present invention;

fig. 4 is a schematic structural diagram of a control device according to a second embodiment of the present invention.

Detailed Description

For a more clear understanding of the technical features, objects and effects of the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

The invention provides a grass mower which can be used for repairing a gardening lawn, can automatically match the rotating speed of a cutter head according to the lawn grass type selected or input by a user, determines the proper advancing speed range of the grass mower according to the rotating speed of the cutter head, and gives an alarm to remind the user when the real-time advancing speed of the grass mower exceeds the proper advancing speed range.

As a first embodiment of the present invention, there is provided a lawnmower including a grass cutting head, a displacement mechanism for moving the grass cutting head, and a rotary motor 21 for rotating the grass cutting head. The control method of the grass mower specifically comprises the following steps:

s1, receiving a selection instruction, wherein the selection instruction comprises lawn grass types, and acquiring a target rotating speed of a cutter head corresponding to the lawn grass types according to the selection instruction;

s2, driving the mowing tool bit to rotate at the tool bit target rotating speed according to the tool bit target rotating speed;

s3, receiving the real-time moving speed of the displacement mechanism, and judging whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed, wherein the first target speed and the second target speed correspond to the target rotating speed of the cutter head, and the first target speed is smaller than the second target speed;

s4, if yes, generating and sending an alarm instruction, and returning to S3; if not, not sending out an alarm instruction, and returning to S3; until the work of the mower is finished.

Specifically, in step S2, the method further includes generating a first control command according to the target rotation speed of the cutter head, wherein the first control command is used for driving the mowing cutter head to rotate at the target rotation speed of the cutter head.

In step S3, a first target speed is obtained by nL/2 π r and a second target speed is obtained by nL/π r, where n is a target rotational speed of the cutter head, L is a length of the cutting edge of the mowing head, and r is a radius of rotation of the mowing head.

In step S4, when the real-time moving speed of the displacement mechanism is less than the first target speed, a first alarm instruction is generated and transmitted; and when the real-time moving speed of the displacement mechanism is greater than the second target speed, generating and sending a second alarm instruction. Continuously monitoring whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed in the whole advancing process of the grass mower, and judging whether a first alarm instruction or a second alarm instruction is sent out, wherein the judging process is continued until the work of the grass mower is finished.

In this embodiment, the present invention also provides a control device 10 adapted to the above control method, the control device 10 including:

the control module 11 is used for receiving the selection instruction and acquiring a target rotating speed of the cutter head corresponding to the lawn grass type according to the selection instruction; driving the mowing tool bit to rotate at the tool bit target rotating speed according to the tool bit target rotating speed; receiving the real-time moving speed of the displacement mechanism, and judging whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed, wherein the first target speed and the second target speed correspond to the target rotating speed of the cutter head, and the first target speed is smaller than the second target speed; if yes, generating and sending an alarm instruction; if not, no alarm instruction is sent;

the receiving module 12 is used for generating a selection instruction according to user operation;

the driving module 13 is used for driving the rotating motor 21 to enable the mowing head to start rotating at the target rotating speed of the mowing head;

the detection module 14 is used for detecting the moving speed of the displacement mechanism and sending a moving speed signal of the displacement mechanism to the control module;

and the alarm module 15 is used for receiving the alarm instruction and giving an alarm.

Specifically, in some embodiments, the receiving module 12 may generate the selection instruction according to a user operation, where the user operation may specifically include a plurality of selection manners such as touch screen selection, key selection, voice selection, image selection, and the like, and the control module 11 stores a plurality of lawn grass categories and target rotation speeds of the cutter head corresponding to the lawn grass categories. The detection module 14 includes a speed sensor for detecting the real-time moving speed of the displacement mechanism, and specifically may include a linear speed sensor and an angular speed sensor. When the real-time moving speed of the displacement mechanism is smaller than the first target speed, the control module 11 sends out a first alarm instruction, and when the real-time moving speed of the displacement mechanism is larger than the second target speed, the control module 11 sends out a second alarm instruction. Accordingly, the alarm module 15 includes at least two alarm modes, and the alarm unit issues a first alarm when receiving a first alarm command, and issues a second alarm different from the first alarm when receiving a second alarm command. The alarm unit may include an audible alarm, a light alarm or other alarms for clearly reminding the user, and the variety of the alarms may be considered to fall within the scope of the present invention.

In some embodiments, the present invention further provides a lawn mower, which includes a mowing head, a displacement mechanism for moving the mowing head, and a rotating electrical machine 21 for rotating the mowing head, the lawn mower further includes the above-mentioned control device 10, and a power supply unit 31 for supplying power to the lawn mower, wherein the rotating electrical machine 21 and the control device 10 are respectively coupled to the power supply unit 31.

Specifically, the displacement mechanism comprises at least two travelling wheels and a frame for mounting the mowing head, and the speed sensor can be mounted on the travelling wheels and can also be mounted at any position of the frame. In some embodiments, the displacement mechanism may further include at least two pushrods fixedly coupled to the frame, through which the lawnmower can be pushed to travel, for user-friendly operation.

In some embodiments, to ensure the safety of the lawn mower, the lawn mower may further include a first switch 32 and a second switch 33, wherein the first switch 32 is disposed between the power supply unit 31 and the control module 11, the second switch 33 is disposed between the power supply unit 31 and the rotating motor 21, when the first switch 32 is turned on by a user, the lawn mower is powered on, the control module 11 obtains a target rotation speed of the blade head, but the blade head is not rotated, and the user may perform a preparation work before mowing; when the user is ready to start the operation, the second switch 33 is turned on, and the rotary motor 21 starts to operate and the mowing head starts to rotate.

In some preferred embodiments, the lawnmower further comprises a grass collection box for collecting the cut stubbles for the user to clean.

In this embodiment, one preferred workflow of the lawnmower is:

the user opens the first switch 32, selects the type of lawn grass to be cut through selection modes such as a touch screen, a key, voice or images, and the like, and the control device 10 automatically matches a proper target rotating speed of the cutter head according to the selected type of lawn grass, and obtains a first target speed and a second target speed, wherein the range between the first target speed and the second target speed is the optimal propelling speed range of the grass mower. After the user is ready for work, the second switch 33 is turned on, the control device 10 drives the rotary motor 21 to start working, and the mowing head starts rotating at the target rotating speed of the mowing head, and the user pushes the mower forward through the push rod. In the process of forward propulsion of the mower, the control device 10 continuously detects the real-time moving speed of the mower, and judges whether the real-time moving speed falls between a first target speed and a second target speed, namely whether the real-time moving speed is in an optimal propulsion speed range, if the real-time moving speed is smaller than the first target speed or larger than the second target speed, the alarm unit gives an alarm to remind a user that the mower is in an under-speed or over-speed state at the moment; when the user adjusts the advancing speed of the mower to enable the speed to be within the optimal advancing speed range, the alarm disappears, and the user can keep the speed to push the mower to work continuously. From the start of the pushing of the lawnmower, the control device 10 continuously detects and determines whether the real-time movement speed falls within the optimal propelling speed range until the work of the lawnmower is finished. After the grass pushing machine finishes working, the second switch 33 and the first switch 32 are closed in sequence, the grass collecting box is taken down, and the stubble is treated.

It is often desirable to achieve an adjusted mowing height of the lawnmower prior to operation of the lawnmower, and it is often necessary for the user to bend over for manual adjustment. This causes two problems, the first being that it is difficult to set the mowing speed at a time without the user having a good sense of lawn care. If the mowing height of the grass mower is adjusted to be too low, stubble remaining on the lawn grass is too low, photosynthesis of the residual stubble is reduced, and the lawn is rapidly declined under severe conditions; if the mowing height of the grass mower is adjusted to be too high, the mowing effect is reduced, the mowing period is shortened, and the mowing times of a user in nursing the same lawn are increased.

Therefore, the present invention provides a second embodiment, in which the lawn mower can also automatically obtain the height of the cutter head corresponding to the type of lawn grass, and avoid the user from bending over and manually adjusting the height. The control method of the grass mower specifically comprises the following steps:

s1, receiving a selection instruction, wherein the selection instruction comprises lawn grass types, and acquiring the target height and the target rotating speed of the cutter head corresponding to the lawn grass types according to the selection instruction;

s2, driving the mowing tool bit to move to the tool bit target height according to the tool bit target height, and driving the mowing tool bit to rotate at the tool bit target rotating speed according to the tool bit target rotating speed;

s3, receiving the real-time moving speed of the displacement mechanism, and judging whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed, wherein the first target speed and the second target speed correspond to the target rotating speed of the cutter head, and the first target speed is smaller than the second target speed;

s4, if yes, generating and sending an alarm instruction, and returning to S3; if not, not sending out an alarm instruction, and returning to S3; until the work of the mower is finished.

Specifically, in step S2, generating a second control command according to the target height of the cutter head, where the second control command is used to drive the mowing cutter head to move to the target height of the cutter head; and generating a first control instruction according to the target rotating speed of the cutter head, wherein the first control instruction is used for driving the mowing cutter head to rotate at the target rotating speed of the cutter head. Meanwhile, step S2 further includes receiving a real-time height signal of the mowing head for obtaining real-time height information of the mowing head.

In step S3, a first target speed is obtained by nL/2 π r and a second target speed is obtained by nL/π r, where n is a target rotational speed of the cutter head, L is a length of the cutting edge of the mowing head, and r is a radius of rotation of the mowing head.

In step S4, when the real-time moving speed of the displacement mechanism is less than the first target speed, a first alarm instruction is generated and transmitted; and when the real-time moving speed of the displacement mechanism is greater than the second target speed, generating and sending a second alarm instruction. Continuously monitoring whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed in the whole advancing process of the grass mower, and judging whether a first alarm instruction or a second alarm instruction is sent out, wherein the judging process is continued until the work of the grass mower is finished.

In this embodiment, the present invention also provides a control device 10 adapted to the above control method, the control device 10 including:

the control module 11 is used for receiving the selection instruction and acquiring the target height and the target rotating speed of the cutter head corresponding to the lawn grass type according to the selection instruction; driving the mowing tool bit to move to the tool bit target height according to the tool bit target height, and driving the mowing tool bit to rotate at a tool bit target rotating speed according to a tool bit target rotating speed; receiving the real-time moving speed of the displacement mechanism, and judging whether the real-time moving speed of the displacement mechanism is smaller than a first target speed or larger than a second target speed, wherein the first target speed and the second target speed correspond to the target rotating speed of the cutter head, and the first target speed is smaller than the second target speed; if yes, generating and sending an alarm instruction; if not, no alarm instruction is sent;

the receiving module 12 is used for generating a selection instruction according to user operation;

the driving module 13 is used for driving the lifting motor 22 to move the mowing head to a target height of the mowing head; the rotary motor 21 is also used for driving the mowing head to rotate at the target rotating speed of the mowing head;

the detection module 14 is used for detecting the moving speed of the displacement mechanism and sending a moving speed signal of the displacement mechanism to the control module 11; and detecting the real-time height of the mowing head and sending a real-time height signal of the mowing head to the control module 11.

And the alarm module 15 is used for receiving the alarm instruction and giving an alarm.

Specifically, in some embodiments, the receiving module 12 may generate the selection instruction according to a user operation, where the user operation may specifically include a plurality of selection manners such as touch screen selection, key selection, voice selection, image selection, and the like, and the control module 11 stores a plurality of lawn grass categories, and a cutter head target height and a cutter head target rotation speed corresponding to the plurality of lawn grass categories. The detection module 14 comprises a distance sensor for detecting the real-time height of the mowing head, and a speed sensor for detecting the real-time moving speed of the displacement mechanism, wherein the speed sensor can specifically comprise a linear speed sensor and an angular speed sensor. When the real-time moving speed of the displacement mechanism is smaller than the first target speed, the control module 11 sends out a first alarm instruction, and when the real-time moving speed of the displacement mechanism is larger than the second target speed, the control module 11 sends out a second alarm instruction. Accordingly, the alarm module 15 includes at least two alarm modes, and the alarm unit issues a first alarm when receiving a first alarm command, and issues a second alarm different from the first alarm when receiving a second alarm command. The alarm unit may include an audible alarm, a light alarm or other alarms for clearly reminding the user, and the variety of the alarms may be considered to fall within the scope of the present invention.

In some embodiments, the present invention further provides a lawn mower, which includes a grass cutting head, a displacement mechanism for moving the grass cutting head, a lifting motor 22 for moving the grass cutting head up and down, and a rotating motor 21 for rotating the grass cutting head, the lawn mower further includes the above-mentioned control device 10, and a power supply unit 31 for supplying power to the lawn mower, wherein the rotating motor 21, the lifting motor 22, and the control device 10 are respectively coupled to the power supply unit 31.

Specifically, the displacement mechanism comprises at least two travelling wheels and a frame for mounting the mowing head, and the speed sensor can be mounted on the travelling wheels and can also be mounted at any position of the frame. In some embodiments, the displacement mechanism may further include at least two pushrods fixedly coupled to the frame, through which the lawnmower can be pushed to travel, for user-friendly operation.

In some embodiments, to ensure the safety of the lawn mower, the lawn mower may further include a first switch 32 and a second switch 33, wherein one end of the first switch 32 is connected to the power supply unit 31, the other end of the first switch is connected to the lifting motor 22 and the control module 11, the second switch 33 is disposed between the power supply unit 31 and the rotating motor 21, when the first switch 32 is turned on by a user, the lawn mower is powered on, the control module 11 obtains a target rotation speed of the cutter head and a target height of the cutter head, the lifting motor 22 drives the lawn mower head to move to the target height of the cutter head, but the lawn mower head does not rotate at this time, and the user can perform a preparation work before mowing at this time; when the user is ready to start the operation, the second switch 33 is turned on, and the rotary motor 21 starts to operate and the mowing head starts to rotate. In some preferred embodiments, the lawnmower further comprises a grass collection box for collecting the cut stubbles for the user to clean.

In this embodiment, one preferred workflow of the lawnmower is:

the user opens the first switch 32, selects the type of lawn grass to be cut through selection modes such as a touch screen, a key, voice or images, and the like, and the control device 10 automatically matches the corresponding target height of the cutter head and the target rotating speed of the cutter head according to the selected type of lawn grass, and obtains a first target speed and a second target speed, wherein the range between the first target speed and the second target speed is the optimal propelling speed range of the grass mower. The lifting motor 22 drives the mowing head to move up and down until the mowing head is located at the target height of the mowing head, and the detection module 14 detects the real-time height of the mowing head at the moment and can display the real-time height on the mower. After the user confirms that the mowing head is lifted up and down, the second switch 33 is turned on, the control device 10 drives the rotating motor 21 to start working, the mowing head starts rotating at the target mowing head rotating speed, and the user pushes the mower forwards through the push rod. In the process of forward propulsion of the mower, the control device 10 continuously detects the real-time moving speed of the mower, and judges whether the real-time moving speed falls between a first target speed and a second target speed, namely whether the real-time moving speed is in an optimal propulsion speed range, if the real-time moving speed is smaller than the first target speed or larger than the second target speed, the alarm unit gives an alarm to remind a user that the mower is in an under-speed or over-speed state at the moment; when the user adjusts the advancing speed of the mower to enable the speed to be within the optimal advancing speed range, the alarm disappears, and the user can keep changing the speed to push the mower to continuously work. From the start of the pushing of the lawnmower, the control device 10 continuously detects and determines whether the real-time movement speed falls within the optimal propelling speed range until the work of the lawnmower is finished. After the grass pushing machine finishes working, the second switch 33 and the first switch 32 are closed in sequence, the grass collecting box is taken down, and the stubble is treated.

The grass pushing machine provided by the invention can automatically match the proper rotating speed of the cutter head according to the grass type of the lawn, and determine the optimal propelling speed according to the rotating speed of the cutter head, so that the problems that a user is difficult to cut the lawn at one time when the user is not familiar with the nursing of the lawn, the phenomenon of cutting missing due to too high propelling speed or the phenomenon that the working efficiency is low due to too low propelling speed and the service life of a battery are reduced are avoided.

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