JP7809054B2 - Walk-behind cultivator - Google Patents

Description

The present invention relates to a walk-behind tiller.

As shown in Patent Document 1, there is a walk-behind cultivator equipped with a body (body frame) supported by running wheels, a control handle extending rearward from the body, and a tilling rotary (drive shaft, tilling tines) located adjacent to and rear of the running wheels.

Japanese Patent Application Laid-Open No. 2019-4820

With this type of walk-behind tiller, if there are hard sections of soil in the field, the tilling rotary has difficulty penetrating the soil and is instead positioned on the ground side due to the tilling reaction force. This causes the tilling rotary to rotate at a faster speed than the running wheels, causing the machine to move, or "dash." There is a demand for a way to prevent this machine from dashing.

The present invention provides a walk-behind tiller that can prevent the machine from dashing.

The walking type cultivator according to the present invention is
The machine comprises a body supported by running wheels, a steering handle extending rearward from the body, a tillage rotary located adjacent to and rearward of the running wheels, and a resistance member supported on the body forward of the running wheels; the resistance member is urged in a direction away from the tillage rotary by a spring connected to the upper part of the resistance member, and is maintained in an operating position by the base of the resistance member contacting and being supported by a stopper portion; when the tillage rotary's height above the ground reaches a predetermined set height position, the resistance member comes into contact with the ground to prevent the tillage rotary from rising further, and does not come into contact with the ground when the tillage rotary's height above the ground is lower than the set height position.

With this configuration, if the set height is set to a height slightly lower than the rotary tiller's ground height at which a vehicle dash is thought to occur, when the rotary tiller rises toward the ground due to the tilling reaction force and its ground height reaches the set height, the resistance member will come into contact with the ground and prevent the rotary tiller from rising any further. Therefore, even if the rotary tiller rises toward the ground due to the tilling reaction force, it will not rise until a vehicle dash occurs, preventing the vehicle from dashing.

When the rotary tiller is driven into the soil, the rotary tiller's height above the ground becomes lower than the set height position, and the resistance member does not come into contact with the ground. Therefore, even though the rotary tiller is equipped with a resistance member, the rotary tiller can be driven into the soil and tilling work can be performed.

In the present invention,
It is preferable that the resistance member be switched between the operating position in which it can come into contact with the ground when the ground height of the tilling rotary reaches the set height position, and a non-operating position in which it does not come into contact with the ground even when the ground height of the tilling rotary reaches the set height position.

With this configuration, when the resistance member switches to the non-operating position, the tillage rotary is raised so that it does not touch the ground, and even if the rotary's height above the ground becomes higher than the set height position, the resistance member does not touch the ground. Therefore, when the machine is turning or moving, the tillage rotary can be lifted so that it does not touch the ground.

In the present invention,
It is preferable that the resistance member be switched between the operating position and the non-operating position by swinging up and down.

With this configuration, the structure of the resistance member and the support structure for the resistance member can be simplified compared to when the resistance member is switched between the active and inactive positions by expanding and contracting or moving up and down, making it possible to prevent the aircraft from dashing at low cost.

In the present invention,
The system is provided with a work clutch that can be switched between a clutch-on state in which power is transmitted to the tillage rotary and a clutch-off state in which power transmission to the tillage rotary is cut off, and a linkage mechanism between the work clutch and the resistance member, and it is preferable that the linkage mechanism changes the resistance member to the active position when the work clutch is switched to the clutch-on state, and changes the resistance member to the non-active position when the work clutch is switched to the clutch-off state.

With this configuration, when the work clutch is switched to the clutched position, the linkage mechanism changes the resistance member to an active position, and when the tillage rotary reaches a set height above the ground, the resistance member touches the ground. This allows work to be carried out easily while preventing the machine from dashing, without requiring any special operations to change the resistance member to the active position. When the work clutch is switched to the clutched position, the linkage mechanism changes the resistance member to a non-active position, and the resistance member does not touch the ground even when the tillage rotary reaches a set height above the ground. This allows work to be carried out easily while lifting the tillage rotor so that it does not touch the soil, without requiring any special operations to change the resistance member to the non-active position.

In the present invention,
The vehicle is provided with left and right running wheels, a differential mechanism switchable between differential allowable transmission, which transmits power to the left and right running wheels while allowing differential movement between the left and right running wheels, and differential locked transmission, which transmits power to the left and right running wheels while preventing differential movement between the left and right running wheels, and a linking mechanism between the differential mechanism and the resistance member, and it is preferable that the linking mechanism changes the resistance member to the active position when the differential mechanism is switched to the differential locked transmission, and changes the resistance member to the non-active position when the differential mechanism is switched to the differential allowable transmission.

With this configuration, when the differential mechanism is switched to differential lock transmission, the linkage mechanism changes the resistance member to an operative position, and when the tiller rotary's ground height reaches the set height, the resistance member touches the ground. This allows the machine to travel straight and easily prevent the machine from dashing, without requiring any special operations to change the resistance member to the operative position. When the differential mechanism is switched to differential allowable transmission, the linkage mechanism changes the resistance member to a non-operative position, and the resistance member does not touch the ground even when the tiller rotary's ground height reaches or exceeds the set height. This allows the machine to travel in a state that makes it easy to turn, without requiring any special operations to change the resistance member to the non-operative position.

In the present invention,
The system is equipped with a height detection sensor that detects the height of the tilling rotary above the ground, an actuator that switches the resistance member between the active position and the non-active position, and a control device that controls the actuator based on detection information from the height detection sensor to change the position of the resistance member between the active position and the non-active position, and it is preferable that the control device changes the resistance member to the active position when the height of the tilling rotary above the ground reaches the set height position.

With this configuration, when the tiller rotary is raised to the set height position, the resistance member automatically assumes an active position. This improves the reliability of the resistance member's control of the tiller rotary's height above the ground.

In the present invention, it is preferable that the control device changes the resistance member to the non-operating position when the height of the tiller rotary above the ground falls below a second set height position that is lower than the set height position.

If the tilling rotary were to immediately change to a non-operating position when its height above the ground fell below the set height, the resistance member would cause inching as the tilling rotary repeatedly moved up and down around the set height. With this configuration, a dead zone is formed between the set height and the second set height, preventing this inching.

This invention includes a height detection sensor that detects the height of the tilling rotary above the ground, an actuator that switches the resistance member between the active position and the inactive position, and a control device that controls the actuator based on detection information from the height detection sensor to change the resistance member between the active position and the inactive position. It is preferable that the control device change the resistance member to the active position when the height of the tilling rotary above the ground becomes higher than a third set height position that is lower than the set height position.

With this configuration, the resistance member automatically assumes its active position before the tiller rotary rises to the set height position. This allows the resistance member to be prepared early, improving the reliability of ground height regulation.

In the present invention, it is preferable that the control device changes the resistance member to the non-operating position when the height of the tiller rotary above the ground falls to or below a fourth set height position, which is lower than the third set height position.

If the tilling rotary were to immediately change to a non-operating position when its height above the ground fell below the third set height, the resistance member would cause inching as the tilling rotary repeatedly moved up and down around the third set height. With this configuration, a dead zone is formed between the third and fourth set heights, preventing this inching.

FIG. FIG. 2 is a side view of the walk-behind cultivator when the resistance member is not in contact with the ground. FIG. 2 is a side view of the walk-behind cultivator with the resistance member in contact with the ground. FIG. 2 is a side view of the walk-behind cultivator with the resistance member in a non-operating position. FIG. 2 is a block diagram of a power transmission device. FIG. 4 is an explanatory diagram of a resistance member attitude changing device.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In the following explanation, with regard to the body of the walk-behind tiller, the direction of arrow F shown in Figure 1 will be referred to as the "front of the body," the direction of arrow B as the "rear of the body," the direction of arrow U as the "upper side of the body," the direction of arrow D as the "lower side of the body," the direction toward the front of the page in Figure 1 as the "right side of the body," and the direction toward the back of the page as the "left side of the body."

[Overall configuration of the walking tiller]
As shown in Figure 1, the walk-behind cultivator has a body 2 supported by a pair of left and right running wheels 1. A motor unit 4 having an engine 3 is provided at the front of the body 2. A tiller 5 is provided at the rear of the body 2. A control handle 6 extends rearward from a handle support unit 6a provided at the rear of the body 2. The body 2 is made up of a transmission case 7, an engine frame 8 extending forward from the front of the transmission case 7 and supporting the engine 3, and other components. A gearshift lever 9 extends rearward from the top of the transmission case 7. The gearshift lever 9 is located above the control handle 6. A main clutch lever 10 and a differential lock lever 11 are provided at the rear of the control handle 6.

[Tillage device]
1, the tilling device 5 is provided adjacent to the rear of the pair of left and right running wheels 1. The tilling device 5 is provided with a tilling rotary 15, a cover 16 for the tilling rotary 15, and a resistance rod 17.

The tillage rotary 15 includes a drive shaft 15a that is rotatably supported on the transmission case 7 while penetrating the lower rear portion of the transmission case 7 from side to side, and multiple tillage tines 15b that are supported on the drive shaft 15a on the outer left and right sides of the transmission case 7. The tillage tines 15b can be attached to the drive shaft 15a in either a down-cutting or an upper-cutting mounting position. The drive shaft 15a can be driven in either a forward rotation direction a shown in Figures 1 and 5 or a reverse rotation direction b shown in Figure 5.

[Power transmission device]
Figure 5 is a block diagram showing a power transmission device 20 that transmits power from the engine 3 to the tillage implement 5 and the traveling wheels 1. In the power transmission device 20, the output of the engine 3 is input to a main clutch 21, and the output of the main clutch 21 is input to a transmission case 7 and distributed and transmitted from the transmission case 7 to the tillage rotary 15 and the traveling wheels 1. As shown in Figure 3, the transmission case 7 is provided with a rotary transmission unit 22, a working clutch 23, a traveling transmission unit 24, a traveling clutch 25, and a wheel differential mechanism 26.

When the main clutch 21 is engaged, it inputs power from the engine 3 to the transmission case 7, enabling the driving of the running wheels 1 and the tiller rotary 15. When it is disengaged, it cuts off the input from the engine 3 to the transmission case 7, stopping the running wheels 1 and the tiller rotary 15. The main clutch 21 is switched between engaged and disengaged by the main clutch lever 10 (see Figure 1), which is connected to the main clutch 21 by an operating cable (not shown) or the like.

The rotary transmission unit 22 is configured to be switchable between forward and reverse transmission. When switched to forward transmission, the power from the main clutch 21 is converted into forward power and output, and when switched to reverse transmission, the power from the main clutch 21 is converted into reverse power and output. The forward power is the power that drives the drive shaft 15a of the tiller rotary 15 in the forward rotation direction (see Figure 1). The reverse power is the power that drives the drive shaft 15a of the tiller rotary 15 in the reverse rotation direction (see Figure 1). The rotary transmission unit 22 is switched between forward and reverse transmission using the speed change lever 9 (see Figure 1).

When the work clutch 23 is switched into the clutch-on position, it transmits forward or reverse rotation power from the rotary transmission unit 22 to the drive shaft 15a, driving the tiller rotary 15 in the forward rotation direction (see Figure 1) or reverse rotation direction (see Figure 1). When switched into the clutch-off position, it cuts off the power transmission from the rotary transmission unit 22 to the drive shaft 15a, stopping the tiller rotary 15. The work clutch 23 is switched between clutch-on and clutch-off by the differential lock lever 11 (see Figure 1), which is connected to the work clutch 23 by an operating cable (not shown) or the like.

The traveling transmission unit 24 receives power from the main clutch 21 and converts it into multiple stages of forward power and one stage of reverse power before outputting it. The traveling transmission unit 24 is operated using the shift lever 9 (see Figure 1).

When the traveling clutch 25 is switched to the clutch-on position, it transmits forward or reverse power from the traveling transmission 24 to the wheel differential mechanism 26, enabling the traveling wheels 1 to move forward or backward. When the clutch is switched to the clutch-off position, it stops the transmission of power from the traveling transmission 24 to the wheel differential mechanism 26, stopping the traveling wheels 1.

The wheel differential mechanism 26 is configured to be switchable between differential transmission and differential lock transmission. When the wheel differential mechanism 26 is switched to differential transmission, power from the traveling clutch 25 is transmitted to the pair of left and right traveling wheels 1, and this power transmission occurs while allowing differential movement between the pair of left and right traveling wheels 1. When the wheel differential mechanism 26 is switched to differential lock transmission, power from the traveling clutch 25 is transmitted to the pair of left and right traveling wheels 1, and this power transmission occurs while preventing differential movement between the pair of left and right traveling wheels 1. The wheel differential mechanism 26 is switched between differential transmission and differential lock transmission by a differential lock lever 11 (see Figure 1) connected to the wheel differential mechanism 26 by an operating cable (not shown) or the like.

[Preventing aircraft from dashing]
As shown in FIG. 1 , a resistance member 30 is supported on the vehicle body 2 forward of the running wheels 1. The resistance member 30 is supported on the vehicle body 2 by a support portion 31 provided at the front of the engine frame 8 and a support shaft 32 located at one end of the resistance member 30 connected to the support portion 31. As shown in FIGS. 2 , 3 , and 4 , the resistance member 30 is supported on the engine frame 8 in a state in which it can be changed between an operating position S (see FIGS. 2 and 3 ) in which it swings downward around an axis P of the support shaft 32 along the left-right direction of the vehicle body as a swing fulcrum, and a non-operating position K (see FIG. 4 ) in which it swings upward. As shown in FIG. 6 , the resistance member 30 is biased downward by a spring 33 connected to the upper part of the resistance member 30, and is held in the operating position S by the base of the resistance member 30 contacting and being supported by a stopper portion 31 a provided on the support portion 31.

When the soil in a field is hard, the rotary tiller 15 has difficulty penetrating the soil and is raised toward the ground by the tilling reaction force. In this case, depending on the height of the rotary tiller 15 above the ground, the rotational speed of the rotary tiller 15 may be faster than the rotational speed of the running wheels 1, causing the rotary tiller 15 to move, or the machine body 2 to dash. A ground height slightly lower than the ground height of the rotary tiller 15 at which machine body dash is thought to occur is pre-set as the set height position [SH]. As shown in Figure 3, the set height position [SH] is set to the ground height position of the axis Y of the drive shaft 15a. The set height position [SH] is not limited to the ground height position of the axis P. It is also possible to set the ground height of any part of the rotary tiller 15, such as the upper or lower end of the rotational trajectory of the tip of the tiller tine 15b, as the set height position.

As shown in Figure 3, when the resistance member 30 is switched to the operating position S, when the height of the tillage rotary 15 above the ground (the height of the axis Y above the ground) reaches the set height position [SH], the machine body 2 assumes a forward-downward position with the axis Z as the pivot point, causing the resistance member 30 to touch the ground. When the resistance member 30 touches the ground, the resistance member 30's tension support prevents the tillage rotary 15 from rising any further.

As shown in Figure 2, even if the resistance member 30 is switched to the operating position S, when the height of the tilling rotary 15 above the ground (height of the axis Y above the ground) is lower than the set height position [SH], the machine body 2 will be in a more forward-raised position than when the height of the tilling rotary 15 above the ground (height of the axis Y above the ground) is at the set height position [SH], and the resistance member 30 will not touch the ground.

As shown in Figure 4, when the resistance member 30 is switched to the non-operating position K, it retracts upward relative to the operating position S. As a result, when the resistance member 30 is switched to the non-operating position K, the ground height of the tiller rotary 15 (ground height of the axis Y) reaches the set height position [SH] and the machine body 2 assumes a forward-downward position, so it does not come into contact with the ground.

As shown in Figure 2, when work is performed, if the resistance member 30 is switched to the operating position S, the resistance member 30 does not touch the ground even when the tilling rotary 15 reaches a ground height where it can penetrate into the soil, allowing the tilling rotary 15 to penetrate into the soil and perform tilling. As shown in Figure 3, even if the soil is hard and the tilling rotary 15 rises toward the ground due to the tilling reaction force, once the tilling rotary 15's ground height reaches the set height position [SH], the resistance member 30 touches the ground and the tilling rotary 15 does not rise above the set height position [SH], preventing the machine body 2 from dashing.

As shown in Figure 4, when the machine body 2 is turning or moving, if the resistance member 30 is switched to the non-operating position K, the tillage rotary 15 is lifted so that it does not touch the soil, and even if the tillage rotary 15's height above the ground reaches the set height position [SH] or higher, the resistance member 30 does not touch the ground, and the tillage rotary 15 can be lifted so that it does not touch the ground.

[Resistance member position change device]
6, the resistance member 30 is linked to the work clutch 23 and the wheel differential mechanism 26 by a linkage mechanism 34. The linkage mechanism 34 links the resistance member 30 to the work clutch 23 and the wheel differential mechanism 26 by connecting the resistance member 30 and the differential lock lever 11 with an operation cable 35.

When the differential lock lever 11 is switched to the off position (off), the working clutch 23 is switched to the clutch disengagement state, and the wheel differential mechanism 26 is switched to the differential transmission mode, the inner cable 35a of the operating cable 35 is pulled, and the resistance member 30 is changed to the non-operating position K by the operating cable 35 against the spring 33. As a result, the linkage mechanism 34 changes the resistance member 30 to the non-operating position K when the working clutch 23 is switched to the clutch disengagement state and the wheel differential mechanism 26 is switched to the differential transmission mode.

When the differential lock lever 11 is switched to the on position [ON], the working clutch 23 is switched to clutch-on, and the wheel differential mechanism 26 is switched to differential lock transmission, the inner cable 35a of the operating cable 35 is loosened and the resistance member 30 is changed to the operating position S by the spring 33. As a result, the linkage mechanism 34 changes the resistance member 30 to the operating position S when the working clutch 23 is switched to clutch-on and the wheel differential mechanism 26 is switched to differential lock transmission.

When working, the work clutch 23 is switched into clutch engagement to drive the tiller rotary 15, and the wheel differential mechanism 26 is switched into differential lock transmission to make it easier for the machine body 2 to travel straight. In this case, by switching the work clutch 23 into clutch engagement and the wheel differential mechanism 26 into differential lock transmission, the resistance member 30 is changed to the working position S by the linkage mechanism 34, and the resistance member 30 can prevent the machine body 2 from dashing without requiring any special operation to change the resistance member 30 to the working position S.

When the machine is turning or traveling, the work clutch 23 is switched to the clutch disengagement position to stop the tillage rotary 15, and the wheel differential mechanism 26 is switched to differential transmission mode to enable differential movement of the left and right traveling wheels 1. In this case, by switching the work clutch 23 to the clutch disengagement position and the wheel differential mechanism 26 to differential transmission mode, the resistance member 30 is changed to the non-operating position K by the linkage mechanism 34, and the tillage rotary 15 can be lifted without touching the soil without performing any special operation to change the resistance member 30 to the non-operating position K.

[Another embodiment]
(1) [First Alternative Embodiment of Resistance Member Attitude Change Device]
The resistance member posture change device of the first alternative embodiment is equipped with a height detection sensor that detects the height of the tilling rotary 15 above the ground, an actuator that switches the resistance member 30, and a control device that controls the actuator based on the detection information from the height detection sensor.

The height detection sensor is mounted on the machine body 2 and detects the fore-and-aft tilt angle with the axle center Z of the machine body 2 as the pivot point as the height of the tiller rotary 15 above the ground.

The actuator is composed of an electric cylinder connected to the resistance member 30, and switches the resistance member 30 between an operating position S and a non-operating position K by extension and contraction. The actuator is not limited to an electric cylinder; an electric motor or the like can also be used.

The control device has a first setting unit that sets the set height position [SH] as the first set height position, and when it determines that the ground height detected by the height detection sensor is the same as the first set height position, it activates the actuator to switch the resistance member 30 to the active position. When the ground height of the tiller rotary 15 reaches the set height position [SH], the control device changes the resistance member 30 to the active position.

The control device has a second setting unit that sets a second set height position that is lower than the set height position [SH], and when it determines that the height above the ground detected by the height detection sensor is equal to or lower than the second set height position, it operates the actuator to switch the resistance member 30 to a non-operating position. When the ground height of the tiller rotary 15 falls below the second set height position, which is lower than the set height position [SH], the control device changes the resistance member 30 to a non-operating position. A dead zone is formed between the set height position [SH] and the second set height position.

In the resistance member position change device of the first alternative embodiment, the control device may not have a second setting unit and may change the resistance member 30 to a non-operating position when the height of the tillage rotary 15 above the ground is lower than the set height position [SH].

(2) [Second Alternative Embodiment of Resistance Member Attitude Change Device]
The resistance member posture change device of the second alternative embodiment is equipped with a height detection sensor that detects the height of the tillage rotary 15 above the ground, an actuator that switches the resistance member 30, and a control device that controls the actuator based on the detection information from the height detection sensor.

The height detection sensor is mounted on the machine body 2 and detects the fore-and-aft tilt angle with the axle center Z of the machine body 2 as the pivot point as the height of the tiller rotary 15 above the ground.

The actuator is composed of an electric cylinder connected to the resistance member 30, and switches the resistance member 30 between an operating position S and a non-operating position K by extension and contraction. The actuator is not limited to an electric cylinder; an electric motor or the like can also be used.

The control device is equipped with a third setting unit that sets a third set height position that is lower than the set height position [SH], and when it determines that the height above ground detected by the height detection sensor is higher than the third set height position, it operates the actuator to switch the resistance member 30 to the active position. The control device changes the resistance member 30 to the active position when the ground height of the tillage rotary 15 becomes higher than the third set height, which is lower than the set height position [SH]. The resistance member 30 automatically switches to the active position before the tillage rotary 15 rises to the set height position [SH], allowing the resistance member 30 to be prepared early.

The control device has a fourth setting unit that sets a fourth set height position that is lower than the third set height position, and when it determines that the height above the ground detected by the height detection sensor is equal to or lower than the fourth set height position, it operates the actuator to switch the resistance member 30 to a non-operating position. When the ground height of the tiller rotary 15 falls below the fourth set height position, which is lower than the third set height position, the control device changes the resistance member 30 to a non-operating position. A dead zone is formed between the third set height position and the fourth set height position.

In the resistance member position change device of the second alternative embodiment, the control device may not include the fourth setting unit, and may change the resistance member 30 to a non-operating position when the height of the tillage rotary 15 above the ground falls below the third set height position.

(3) In the above embodiment, an example was shown in which the resistance member 30 was switchable between an operative position and a non-operative position. However, the resistance member 30 may be fixed only in the operative position.

(4) In the above embodiment, an example was shown in which a pair of left and right running wheels 1 was provided, but a single-wheel type with only one running wheel 1 may also be used.

(5) In the above embodiment, an example was shown in which the resistance member 30 switches between an active position S and a non-active position K around an axis P along the left-right direction of the aircraft body 2 as a swing fulcrum. However, this is not limited to this. The resistance member may also be one that switches between an active position S and a non-active position K around an axis along the front-rear direction of the aircraft body 2 as a swing fulcrum, or one that switches between an active position and a non-active position by expanding and contracting the resistance member, or one that is supported so as to be able to slide up and down and switches between an active position and a non-active position by sliding up and down.

(6) In the above embodiment, an example was shown in which the resistance member 30 was connected to both the work clutch 23 and the wheel differential mechanism 26, but the resistance member 30 may also be connected to only one of the work clutch 23 and the wheel differential mechanism 26.

(7) In the above embodiment, an example was shown in which a linking mechanism 34 was provided that linked the resistance member 30 to the working clutch 23 and the wheel differential mechanism 26. However, the linking mechanism 34 may not be provided, and the resistance member 30 may be manually switched between the operating position S and the non-operating position K.

(8) In the above embodiment, the linking mechanism 34 is configured using an operating cable 35. However, the linking mechanism 34 may also include an actuator that switches the resistance member 30 between the operating position S and the non-operating position K, and a switch that operates the actuator that is operated by the differential lock lever 11.

The present invention can be applied to walk-behind cultivators equipped with running wheels and a tiller rotary located adjacent to and behind the running wheels.

1 Traveling wheel 2 Machine body 6 Control handle 15 Tillage rotary 23 Work clutch 26 Wheel differential mechanism (differential mechanism)
30 Resistance member 34 Linkage mechanism K Non-operating position S Operating position SH Set height position

Claims (9)

a body supported by running wheels;
A control handle extending rearward from the aircraft body;
A tilling rotary located adjacent to the rear of the traveling wheel;
a resistance member supported on the vehicle body forward of the running wheels,
The resistance member is biased in a direction away from the tillage rotary by a spring connected to the upper part of the resistance member, and is held in an operating position by the base of the resistance member contacting and being supported by the stopper portion,
The resistance member comes into contact with the ground when the height of the tilling rotary above the ground reaches a preset height position, preventing the tilling rotary from rising any further, and does not come into contact with the ground when the height of the tilling rotary above the ground is lower than the preset height position. A walk-behind cultivator as described in claim 1, wherein the resistance member switches between an operating position in which it can come into contact with the ground when the ground height of the tilling rotary reaches the set height position, and a non-operating position in which it does not come into contact with the ground even when the ground height of the tilling rotary reaches the set height position. The walk-behind cultivator described in claim 2, wherein the resistance member switches between the operating position and the non-operating position by swinging up and down. a working clutch that can be switched between a clutch-on state for transmitting power to the tilling rotary and a clutch-off state for cutting off power transmission to the tilling rotary;
a linking mechanism between the working clutch and the resistance member,
A walking-type cultivator as described in claim 2 or 3, wherein the linkage mechanism changes the resistance member to the operating position when the work clutch is switched to the clutch-on position, and changes the resistance member to the non-operating position when the work clutch is switched to the clutch-off position. The left and right running wheels are provided,
a differential mechanism switchable between a differential allowable transmission that transmits power to the left and right running wheels while allowing differential movement between the left and right running wheels, and a differential locked transmission that transmits power to the left and right running wheels while preventing differential movement between the left and right running wheels;
a linking mechanism between the differential mechanism and the resistance member,
A walk-behind cultivator as described in claim 2 or 3, wherein the linkage mechanism changes the resistance member to the operating position when the differential mechanism is switched to the differential lock transmission, and changes the resistance member to the non-operating position when the differential mechanism is switched to the differential allowable transmission. The tilling rotary is provided with a height detection sensor that detects the height of the tilling rotary from the ground, an actuator that switches the resistance member between the working position and the non-working position, and a control device that controls the actuator based on detection information from the height detection sensor to change the position of the resistance member between the working position and the non-working position,
3. The walk-behind cultivator according to claim 2, wherein the control device changes the resistance member to the operating position when the height of the tilling rotary above the ground reaches the set height position. The walk-behind cultivator described in claim 6, wherein the control device changes the resistance member to the non-operating position when the height of the tilling rotary above the ground falls below a second set height position that is lower than the set height position. The tilling rotary is provided with a height detection sensor that detects the height of the tilling rotary from the ground, an actuator that switches the resistance member between the working position and the non-working position, and a control device that controls the actuator based on detection information from the height detection sensor to change the resistance member between the working position and the non-working position,
The walk-behind cultivator according to claim 2, wherein the control device changes the resistance member to the operating position when the ground height of the tilling rotary becomes higher than a third set height position that is lower than the set height position. The walk-behind cultivator described in claim 8, wherein the control device changes the resistance member to the non-operating position when the height of the tilling rotary above the ground falls below a fourth set height position that is lower than the third set height position.