JP7763748B2 - Walk-behind cultivator - Google Patents

Description

The present invention relates to a walk-behind cultivator with a tilling device mounted at the rear of the machine body supported by a traveling device.

As disclosed in Patent Document 1, the tillage device has a tine shaft attached to the drive shaft of the machine body, and tillage tines attached to the tine shaft. In the tillage device, the tine shaft (drive shaft) is driven to rotate in the forward direction so that the tines pass from above the front of the tine shaft, penetrate the ground, and push soil from the ground rearward (see R1 in Figure 1 of Patent Document 1).

The tine shaft is attached to the drive shaft in a forward orientation (see 30 (28) in Figure 1 of Patent Document 1), with the tine shaft positioned further upstream in the forward rotation direction as it moves radially outward from the tine shaft. As a result, in a walk-behind cultivator, the normal tilling state is when the tine shaft is attached to the drive shaft in a forward orientation and the tine shaft is driven to rotate in the forward rotation direction.

In some tillage devices, the tines are configured so that the tine shaft can be attached to the drive shaft in a reverse orientation, which positions the tines further radially outward from the tine shaft toward the downstream side in the forward rotation direction, in contrast to the forward orientation described above, and the tine shaft can be changed between the forward orientation and the reverse orientation.

JP 2016-10384 A

In a tillage device, when the tine shaft is attached to the drive shaft in an inverted position and driven to rotate in the forward direction, the tip of the tillage tine penetrates into the ground before the middle part of the tillage tine, and a large reaction force from the ground is generated, pushing the tillage device forward strongly.
This can cause the walk-behind cultivator to be pushed forward by the force strongly pushing the tillage implement forward (hereinafter referred to as "dashing").

The present invention aims to prevent dashing in a walk-behind cultivator equipped with a tillage device in which the tines can be moved between a forward and reverse orientation.

The walk-behind cultivator of the present invention comprises a body supported by a traveling device, a drive shaft supported in the left-right direction at the rear of the body, a tine shaft portion attached to the drive shaft, and tillage tines attached to the tine shaft portion. The tillage device is driven by the drive shaft, and the tines pass from the top to the front of the tine shaft portion and penetrate into the ground, pushing soil from the ground rearward. The tillage device is a forward rotation position that transmits power to the drive shaft, and a power supply to the drive shaft. The tine shaft can be attached to the drive shaft in a forward orientation, in which the portion of the tine that is radially outward from the tine shaft is positioned upstream in the forward rotation direction, and in a reverse orientation, in which the portion of the tine that is radially outward from the tine shaft is positioned downstream in the forward rotation direction. The tine shaft is equipped with a check mechanism that prevents the tine shaft from being attached to the drive shaft in the reverse orientation and the transmission device from being operated to the forward rotation position.

According to the present invention, the restraining unit can prevent the claw shaft from being attached to the drive shaft in a reverse orientation and the claw shaft (drive shaft) from being driven to rotate in the forward direction. This makes it easier to avoid dashing in walk-behind cultivators equipped with tillage devices in which the claw shaft can be changed between a forward orientation and a reverse orientation.

In the present invention, it is preferable that the restraining unit include an attitude detection unit that detects that the claw shaft is attached to the drive shaft in the reverse attitude, and a forward rotation restraining unit that prevents the transmission device from being operated to the forward rotation position when the attitude detection unit detects that the claw shaft is attached to the drive shaft in the reverse attitude.

According to the present invention, when the tine shaft portion is attached to the drive shaft in an inverted orientation in the tillage implement, this is detected by the orientation detection portion.
In the above-mentioned state, even if the worker attempts to operate the transmission device to the forward rotation position, the forward rotation restraint section will prevent the transmission device from being operated to the forward rotation position based on the detection by the posture detection section, so the worker can recognize that the claw shaft section is attached to the drive shaft in an inverted position.
This allows the operator to simply attach the tine shaft portion to the drive shaft in the tillage implement in a forward position, and then operate the transmission device to the forward rotation position.

In the present invention, the tillage implement has a first claw shaft attached to one of the right and left portions of the drive shaft, and a second claw shaft attached to the other of the right and left portions of the drive shaft, and is equipped with a right attitude detection unit that detects when the claw shaft is attached to the right portion of the drive shaft in the reverse attitude, and a left attitude detection unit that detects when the claw shaft is attached to the left portion of the drive shaft in the reverse attitude, and the forward rotation restraint unit preferably prevents operation of the transmission device to the forward rotation position when the right attitude detection unit detects that the claw shaft is attached to the right portion of the drive shaft in the reverse attitude, or when the left attitude detection unit detects that the claw shaft is attached to the left portion of the drive shaft in the reverse attitude.

Some tillage implements have a first tine shaft portion attached to one of the right and left portions of the drive shaft, and a second tine shaft portion attached to the other of the right and left portions of the drive shaft.
According to the present invention, a right attitude detection unit and a left attitude detection unit are provided, and when either the first claw drive shaft or the second claw drive shaft is attached to the drive shaft in an inverted attitude, the forward rotation restraint unit functions, which is advantageous in terms of avoiding dashing of the walking cultivator.

In the present invention, the first claw shaft portion and the second claw shaft portion can be attached to the drive shaft in an inward position where the tillage tines face toward the left-right center of the tillage device in a rear view, and in an outward position where the tillage tines face outward from the left-right center of the tillage device in a rear view. It is preferable that the position detection unit detects when the claw shaft portion is attached to the drive shaft in the inward position and the inward position, and also detects when the claw shaft portion is attached to the drive shaft in the inward position and the outward position.

In a tillage device, when a first claw shaft portion and a second claw shaft portion are provided, the tillage device may be configured so that the first claw shaft portion can be attached to the right part of the drive shaft and the second claw shaft portion can be attached to the left part of the drive shaft, or conversely, the first claw shaft portion can be attached to the left part of the drive shaft and the second claw shaft portion can be attached to the right part of the drive shaft.
This allows the claw shaft portion to be attached to the drive shaft in an inward orientation, and the claw shaft portion to be attached to the drive shaft in an outward orientation.

According to the present invention, even if the claw shaft portion is attached to the drive shaft in an inverted or inward orientation, or even if the claw shaft portion is attached to the drive shaft in an inverted or outward orientation, this can be detected by the orientation detection portion.
This allows the forward rotation restraint section to function whether the claw shaft section is attached to the drive shaft in an inverted or inward position, or whether the claw shaft section is attached to the drive shaft in an inverted or outward position, which is advantageous in terms of avoiding dashing in a walk-behind cultivator.

In the present invention, it is preferable that the restraining unit include a forward rotation detection unit that detects when the transmission device has been operated to the forward rotation position, and a claw shaft restraining unit that prevents the claw shaft from being attached to the drive shaft in the reverse orientation when the forward rotation detection unit detects that the transmission device has been operated to the forward rotation position.

According to the present invention, when the transmission device is operated to the forward rotation position, this is detected by the forward rotation detection unit.
In the above-mentioned state, even if the worker attempts to attach the claw shaft portion to the drive shaft in the reverse position, the claw shaft restraining section will prevent the claw shaft portion from being attached to the drive shaft in the reverse position based on the detection of the forward rotation detection section, so the worker can recognize that he or she is attempting to attach the claw shaft portion to the drive shaft in the reverse position.
This allows the operator to simply attach the pawl shaft portion to the drive shaft in a normal orientation.

In the present invention, the tillage implement has a first claw shaft portion attached to one of the right and left portions of the drive shaft, and a second claw shaft portion attached to the other of the right and left portions of the drive shaft, and the claw shaft restraining unit preferably prevents the claw shaft portion from being attached to the right portion of the drive shaft in the reverse position when the forward rotation detection unit detects that the transmission device has been operated to the forward rotation position, and also prevents the claw shaft portion from being attached to the left portion of the drive shaft in the reverse position.

Some tillage implements have a first tine shaft portion attached to one of the right and left portions of the drive shaft, and a second tine shaft portion attached to the other of the right and left portions of the drive shaft.
According to the present invention, when the transmission device is operated to the forward rotation position and this is detected by the forward rotation detection unit, even if an operator attempts to attach the claw shank in the reverse position to the right portion of the drive shaft, the claw shank restraining unit prevents the claw shank from being attached to the right portion of the drive shaft in the reverse position.Similarly, even if an operator attempts to attach the claw shank in the reverse position to the left portion of the drive shaft, the claw shank restraining unit prevents the claw shank from being attached to the left portion of the drive shaft in the reverse position.

This allows the worker to recognize at an early stage when they attempt to attach the claw shaft in the wrong position to either the right or left part of the drive shaft.

In the present invention, the restraining unit preferably includes an attitude detection unit that detects when the claw shaft is attached to the drive shaft in the reverse attitude; a forward rotation detection unit that detects when the transmission device is operated to the forward rotation position; a forward rotation restraining unit that prevents operation of the transmission device to the forward rotation position when the attitude detection unit detects that the claw shaft is attached to the drive shaft in the reverse attitude; and a claw shaft restraining unit that prevents attachment of the claw shaft to the drive shaft in the reverse attitude when the forward rotation detection unit detects that the transmission device has been operated to the forward rotation position.

According to the present invention, when the tine shaft portion is attached to the drive shaft in an inverted orientation in the tillage implement, this is detected by the orientation detection portion.
In the above-mentioned state, even if the worker attempts to operate the transmission device to the forward rotation position, the forward rotation restraint section will prevent the transmission device from being operated to the forward rotation position based on the detection by the posture detection section, so the worker can recognize that the claw shaft section is attached to the drive shaft in an inverted position.
This allows the operator to simply attach the tine shaft portion to the drive shaft in the tillage implement in a forward position, and then operate the transmission device to the forward rotation position.

According to the present invention, when the transmission device is operated to the forward rotation position, this is detected by the forward rotation detection unit.
In the above-mentioned state, even if the worker attempts to attach the claw shaft portion to the drive shaft in the reverse position, the claw shaft restraining section will prevent the claw shaft portion from being attached to the drive shaft in the reverse position based on the detection of the forward rotation detection section, so the worker can recognize that he or she is attempting to attach the claw shaft portion to the drive shaft in the reverse position.
This allows the operator to simply attach the pawl shaft portion to the drive shaft in a normal orientation.

As described above, this invention prevents the claw shaft from being attached to the drive shaft in an inverted position, causing the claw shaft (drive shaft) to be driven to rotate in the forward direction, which is advantageous in preventing dashing in walk-behind tillers.

In this invention, a claw shaft blocking member operable to an attachment blocking position that prevents attachment of the claw shaft portion to the drive shaft and an attachment allowing position that allows attachment of the claw shaft portion to the drive shaft; an operating unit provided on the claw shaft that, when the claw shaft portion is attached to the drive shaft in the reverse orientation, comes into contact with the claw shaft blocking member and operates the claw shaft blocking member to the attachment allowing position; a forward rotation blocking member operable to a forward rotation blocking position that prevents operation of the transmission device to the forward rotation position and to a forward rotation allowing position that allows operation of the transmission device to the forward rotation position and prevents operation to the forward rotation blocking position when the transmission device is operated to the forward rotation position; and a mechanism connected between the forward rotation blocking member and the claw shaft blocking member. and a linking member, and when the claw shaft portion is attached to the drive shaft in the reverse orientation, the claw shaft blocking member is operated to the attachment allowable position by the operating unit, and the forward rotation blocking member is operated to the forward rotation blocking position via the linking member; when the forward rotation blocking member is operated to the forward rotation allowable position, the claw shaft blocking member is operated to the attachment blocking position via the linking member; and when the transmission device is operated to the forward rotation position, the claw shaft blocking member is held at the attachment blocking position via the forward rotation blocking member and the linking member; the claw shaft blocking member is preferably the orientation detection unit and the claw shaft restraining unit, and the forward rotation blocking member is the forward rotation detection unit and the forward rotation restraining unit.

According to the present invention, a forward rotation preventing member and a pawl shaft blocking member are provided, and the forward rotation preventing member and the pawl shaft blocking member are connected via a linking member. When the pawl shaft blocking member is operated to the installation allowance position, the forward rotation preventing member is operated to the forward rotation preventing position via the linking member, and when the forward rotation preventing member is operated to the forward rotation allowance position, the pawl shaft blocking member is operated to the installation block position via the linking member.

According to the present invention, when the pawl shaft portion is attached to the drive shaft in a reverse orientation without the transmission device being operated to the forward rotation position, the operating portion of the pawl shaft portion comes into contact with the pawl shaft blocking member, and the operating portion of the pawl shaft portion operates the pawl shaft blocking member to the attachment allowance position. When the pawl shaft blocking member is operated to the attachment allowance position, this operation is transmitted to the forward rotation blocking member via the linkage member, and the forward rotation blocking member is operated to the forward prevention position.
As a result, even if an operator attempts to operate the transmission device to the forward rotation position, the operator cannot operate the transmission device to the forward rotation position because the forward rotation preventing member has been operated to the forward rotation preventing position.

According to the present invention, when the transmission device is operated to the forward rotation position while the claw shaft portion is not attached to the drive shaft in an inverted position (when the claw shaft blocking member is operated to the attachment blocking position), the forward rotation blocking member cannot move to the forward rotation blocking position and is held in the forward rotation allowing position, so that the claw shaft blocking member is held in the attachment blocking position via the forward rotation blocking member and the connecting member.
As a result, even if an operator attempts to attach the claw shaft portion to the drive shaft in an inverted position, the operating part of the claw shaft portion will come into contact with the claw shaft blocking member held in the attachment blocking position, making it impossible to attach the claw shaft portion to the drive shaft in an inverted position.

As described above, according to the present invention, when a forward rotation preventing member and a pawl shaft blocking member are provided, the forward rotation preventing member and the pawl shaft blocking member are mechanically connected via a linking member, which is a simple configuration that prevents the pawl shaft portion from being attached to the drive shaft in an inverted position and causing the pawl shaft portion (drive shaft) to be rotated in the forward direction, thereby simplifying the structure.

According to the present invention, the claw shaft blocking member functions as both a position detection unit that detects when the claw shaft is attached to the drive shaft in an inverted position, and a claw shaft restraining unit that prevents the claw shaft from being attached to the drive shaft in an inverted position. This dual function simplifies the structure.

According to the present invention, the forward rotation prevention member functions as both a forward rotation detection section that detects when the transmission device has been operated to the forward rotation position and a forward rotation restraint section that prevents the transmission device from being operated to the forward rotation position. This dual function simplifies the structure.

In the present invention, it is preferable that the operating portion is provided around the entire circumference of the claw shaft portion, and that the operating portion contacts the claw shaft blocking member regardless of the phase in the rotational direction of the drive shaft when the claw shaft portion is attached in the reverse orientation.

In tillage equipment, when the drive shaft is stopped and then the tine shaft is attached to the drive shaft, it is not known at what rotational phase the drive shaft will stop, and therefore it is not known at what phase in the rotational direction of the drive shaft the tine shaft will be attached to the drive shaft.

According to the present invention, the operating portion is provided around the entire circumference of the claw shaft portion, and the operating portion comes into contact with the claw shaft blocking member regardless of the phase in the rotational direction of the drive shaft when the claw shaft portion is attached in an inverted position.
This allows the claw shaft blocking member to function as a posture detection unit and a claw shaft restraint unit, regardless of whether the claw shaft is attached (or is about to be attached) in an inverted position and in any phase of the rotational direction of the drive shaft, which is advantageous in terms of avoiding dashing in walk-behind cultivators.

In the present invention, the tillage implement has a first claw shaft portion attached to one of the right and left portions of the drive shaft, and a second claw shaft portion attached to the other of the right and left portions of the drive shaft. It is equipped with a right claw shaft blocking member operable to an attachment blocking position that prevents attachment of the claw shaft portion to the right portion of the drive shaft and an attachment allowing position that allows attachment of the claw shaft portion to the right portion of the drive shaft, and a left claw shaft blocking member operable to an attachment blocking position that prevents attachment of the claw shaft portion to the left portion of the drive shaft and an attachment allowing position that allows attachment of the claw shaft portion to the left portion of the drive shaft. It is preferable that the forward rotation blocking member be operated to the forward rotation blocking position via the linkage member by at least one of the right claw shaft blocking member being operated to the attachment allowing position and the left claw shaft blocking member being operated to the attachment allowing position.

Some tillage implements have a first tine shaft portion attached to one of the right and left portions of the drive shaft, and a second tine shaft portion attached to the other of the right and left portions of the drive shaft.
According to the present invention, a right claw shaft blocking member and a left claw shaft blocking member are provided, and when either the first claw drive shaft or the second claw drive shaft is attached to the drive shaft in an inverted position, the forward rotation blocking member functions as a forward rotation restraint part, which is advantageous in terms of avoiding dashing of the walk-behind tiller.

In the present invention, when the transmission device is operated to the forward rotation position, it is preferable that the right claw shaft blocking member and the left claw shaft blocking member are held in the mounting blocking position via the forward rotation blocking member and the linking member.

According to the present invention, when the transmission device is operated to the forward rotation position and the forward rotation preventing member is held in the forward rotation allowing position, the right claw shaft preventing member and the left claw shaft preventing member are held in the mounting preventing position via the forward rotation preventing member and the connecting member.
Even if an operator attempts to attach the claw shank to the right side of the drive shaft in the reverse position, the right claw shank blocking member will prevent the claw shank from being attached to the right side of the drive shaft in the reverse position.Similarly, even if an operator attempts to attach the claw shank to the left side of the drive shaft in the reverse position, the left claw shank blocking member will prevent the claw shank from being attached to the left side of the drive shaft in the reverse position.
This allows the worker to recognize that he or she is attempting to attach the claw shaft portion to the drive shaft in an inverted position at an early stage when he or she attempts to attach the claw shaft portion to one of the right and left parts of the drive shaft in an inverted position.

In the present invention, the tillage implement has a first claw shaft portion attached to one of the right and left portions of the drive shaft, and a second claw shaft portion attached to the other of the right and left portions of the drive shaft. The first claw shaft portion and the second claw shaft portion can be attached to the drive shaft in an inward position in which the tillage tines face toward the left-right center of the tillage implement in a rear view, and an outward position in which the tillage tines face outward from the left-right center of the tillage implement in a rear view. When the claw shaft portion is attached to the drive shaft in the inverted position or the inward position, the operating unit can operate the claw shaft blocking member to the allowable attachment position by contacting the claw shaft blocking member. When the claw shaft portion is attached to the drive shaft in the inverted position or the outward position, the operating unit can operate the claw shaft blocking member to the allowable attachment position by contacting the claw shaft blocking member. and an avoidance portion is provided on the claw shaft blocking member so that when the claw shaft portion is attached to the drive shaft in the forward orientation and the inward orientation, the operating portion prevents the operating portion from hitting the claw shaft blocking member, and when the claw shaft portion is attached to the drive shaft in the forward orientation and the outward orientation, the operating portion operates the claw shaft blocking member to the attachment allowable position when the claw shaft portion is attached to the drive shaft in the backward orientation and the inward orientation, and the forward rotation preventing member is operated to the forward rotation preventing position via the linking member, and when the claw shaft portion is attached to the drive shaft in the backward orientation and the outward orientation, the operating portion operates the claw shaft blocking member to the attachment allowable position when the claw shaft portion is attached to the drive shaft in the backward orientation and the outward orientation, and the forward rotation preventing member is operated to the forward rotation preventing position via the linking member.

According to the present invention, when the pawl shaft portion is attached to the drive shaft in a reverse or inward position while the transmission device is not in the forward rotation position (when the pawl shaft portion is attached to the drive shaft in a reverse or outward position), the pawl shaft blocking member is operated to the attachment-permitting position and the forward rotation blocking member is operated to the forward rotation blocking position, preventing the operator from operating the transmission device in the forward rotation position.

According to the present invention, when the transmission device is operated to the forward rotation position and the forward rotation preventing member is held in the forward rotation allowing position, even if an operator attempts to attach the pawl shaft portion to the drive shaft in a reverse or inward position (reverse or outward position), the operator is unable to attach the pawl shaft portion to the drive shaft in a reverse or inward position (reverse or outward position).

This prevents the claw shaft from being attached to the drive shaft in a reverse or inward position (reverse or outward position), causing the claw shaft (drive shaft) to be driven to rotate in the forward direction, which is advantageous in preventing dashing of walk-behind tillers.

When a tillage implement is provided with a first tine shaft portion and a second tine shaft portion, the tine shaft portions can be attached to the drive shaft in a reverse position and an inward position (reverse position and outward position), and the tine shaft portions can also be attached to the drive shaft in a forward position and an inward position (forward position and outward position).

According to the present invention, even if the claw shaft portion is attached to the drive shaft in a forward position and an inward position (forward position and outward position), the avoidance portion prevents the operating portion from hitting the claw shaft blocking member, and the claw shaft blocking member is not operated to the attachment-permitting position, so the forward rotation blocking member is not operated to the forward rotation blocking position.
This means that when the claw shaft portion is attached to the drive shaft in a forward position and an inward position (forward position and outward position), the transmission device can be operated to the forward rotation position without any hindrance, so there is no reduction in the workability of the walk-behind cultivator.

According to the present invention, even if the transmission device is operated to the forward rotation position and the claw shaft blocking member is held in the mounting blocking position, when the claw shaft portion is mounted on the drive shaft in the forward orientation and inward orientation (forward orientation and outward orientation), the avoidance portion prevents the operating portion from coming into contact with the claw shaft blocking member.
This allows the claw shaft portion to be attached to the drive shaft without any problems in the forward position and inward position (forward position and outward position), so that the workability of the walk-behind cultivator is not reduced.

In the present invention, it is preferable that the operating portion is provided around the entire circumferential circumference of the claw shank and abuts against the claw shank blocking member regardless of the phase in the rotational direction of the drive shaft when the claw shank is attached to the drive shaft in the reverse or inward orientation, or the phase in the rotational direction of the drive shaft when the claw shank is attached to the drive shaft in the reverse or outward orientation, and that the avoidance portion is provided around the entire circumferential circumference of the operating portion and averts the operating portion from abutting against the claw shank blocking member regardless of the phase in the rotational direction of the drive shaft when the claw shank is attached to the drive shaft in the forward or inward orientation, or the phase in the rotational direction of the drive shaft when the claw shank is attached to the drive shaft in the forward or outward orientation.

In tillage equipment, when the drive shaft is stopped and then the tine shaft is attached to the drive shaft, it is not known at what rotational phase the drive shaft will stop, and therefore it is not known at what phase in the rotational direction of the drive shaft the tine shaft will be attached to the drive shaft.

According to the present invention, the operating portion is provided around the entire circumferential direction of the claw shaft portion, and the operating portion comes into contact with the claw shaft blocking member regardless of whether the claw shaft portion is attached (or is about to be attached) in the reverse position or inward position (reverse position or outward position) and in any phase of the rotation direction of the drive shaft.
This allows the claw shaft blocking member to function as a posture detection unit and a claw shaft restraint unit, regardless of whether the claw shaft is attached (or is about to be attached) in an inverted or inward position (inverted or outward position) or in any phase of the rotational direction of the drive shaft, which is advantageous in terms of avoiding dashing in walk-behind cultivators.

According to the present invention, an avoidance portion is provided around the entire circumferential circumference of the operating portion, and the avoidance portion prevents the operating portion from hitting the claw shaft blocking member, regardless of whether the claw shaft portion is attached (or is about to be attached) in a reverse or inward position (reverse or outward position) or at any phase in the rotational direction of the drive shaft.
This allows the claw shaft portion to be attached to the drive shaft without any problems in the forward position and inward position (forward position and outward position), so that the workability of the walk-behind cultivator is not reduced.

FIG. FIG. 2 is a schematic diagram showing the transmission system inside the transmission case. FIG. FIG. 2 is a rear view of the tine shaft portion and the tillage tine in the tillage implement. FIG. 4 is a left side view showing the inside of the transmission case. FIG. FIG. FIG. 10 is a rear view of the vicinity of the claw shaft blocking member and the drive shaft. FIG. 2 is a plan view of the vicinity of the claw shaft blocking member and the drive shaft. 10 is a schematic diagram showing a state in which the pawl shaft portion is attached to the drive shaft in a reverse orientation and an inward orientation, and the shift lever cannot be operated to the normal rotation position. FIG. 10 is a schematic diagram showing a state in which the pawl shaft portion is attached to the drive shaft in a reverse orientation and an outward orientation, and the shift lever cannot be operated to the normal rotation position. FIG. 10 is a schematic diagram showing a state in which the speed change lever is operated to a normal rotation position and the pawl shaft portion cannot be attached to the drive shaft in a reverse orientation or an inward orientation. FIG. 10 is a schematic diagram showing a state in which the speed change lever is operated to a normal rotation position and the pawl shaft portion cannot be attached to the drive shaft in a reverse orientation or an outward orientation. FIG. 10 is a schematic diagram showing a state in which the pawl shaft portion is attached to the drive shaft in a forward orientation and an inward orientation, and the shift lever can be operated to a forward rotation position. FIG. 10 is a schematic diagram showing a state in which the pawl shaft portion is attached to the drive shaft in a forward position and an outward position, and the shift lever can be operated to a forward rotation position. FIG.

Figures 1 to 15 show a walk-behind tiller, and in Figures 1 to 15, F indicates the forward direction, B indicates the rearward direction, U indicates the upward direction, D indicates the downward direction, R indicates the rightward direction, and L indicates the leftward direction.

(Overall configuration of the walk-behind tiller)
As shown in Figure 1, right and left running wheels 1 (corresponding to running devices) are provided on the bottom of a transmission case 2 (corresponding to the vehicle body), and the transmission case 2 is supported by the wheels 1. A support frame 3 is connected to the front of the transmission case 2, and an engine 4 is supported by the support frame 3.

A control handle 5 is connected to the top of the transmission case 2 and extends diagonally rearward and upward from the transmission case 2, and a speed change lever 6 extends diagonally rearward and upward from the transmission case 2. A rotary-type tiller 7 is provided at the rear of the transmission case 2.

As shown in Figure 2, the input shaft 8 is supported in the left-right direction on the upper part of the transmission case 2, and the power of the engine 4 is transmitted to the input shaft 8 via a transmission belt 9. A transmission 10 for traveling is provided inside the transmission case 2, and the power of the input shaft 8 is transmitted to the wheels 1 after being changed in speed by the transmission 10 as described below.

The drive shaft 11 is supported in the left-right direction at the rear of the transmission case 2. A forward/reverse rotation device 12 (corresponding to the transmission device) is provided inside the transmission case 2, and the power of the input shaft 8, as well as forward and reverse power from the forward/reverse rotation device 12, as described below, is transmitted to the drive shaft 11, driving the drive shaft 11 to rotate, which in turn drives the tiller 7.

With the above configuration, as shown in Figure 1, the vehicle is equipped with a body (transmission case 2) supported by a traveling device (wheels 1). A drive shaft 11 is supported in the left-right direction at the rear of the body (transmission case 2).

(Configuration of transmission)
As shown in FIG. 2, the transmission 10 is configured as described below to be capable of shifting to two forward speeds and one reverse speed, and is operated by a speed change lever 6.

Transmission shafts 13, 14, and 15 are supported inside transmission case 2 parallel to input shaft 8. Shift gear 16 is supported via a spline structure so that it can rotate and slide integrally with input shaft 8, and shift gear 17 is supported so that it can rotate and slide relative to transmission shaft 13. Transmission gears 18 and 19 are connected to transmission shaft 14, and transmission gear 20 is connected to transmission shaft 15, with transmission gears 19 and 20 meshing.

A differential device 21 is provided at the bottom of the transmission case 2, and a transmission chain 22 is attached between the transmission shaft 15 and the differential device 21. Right and left axles 23 extend to the right and left from the differential device 21, and the wheels 1 are attached to the axles 23.

A shift fork 24 is provided to slide the shift gear 16. The shift fork 24 allows the shift gear 16 to be moved to three positions: a position where it engages with the transmission gear 18, a position where it engages with the shift gear 17, and a position where it does not engage with either the transmission gear 18 or the shift gear 17.

A shift fork 25 is provided to slide the shift gear 17. The shift fork 25 allows the shift gear 17 to be moved to three positions: a position where it engages with the transmission gear 18, a position where it engages with the transmission gear 20, and a position where it does not engage with the transmission gears 18 and 20.

(Shifting operation of transmission)
2 and 3, a lever guide 26 is attached to the upper part of the transmission case 2, and the speed change lever 6 extends obliquely upward and rearward through the lever guide 26. The speed change lever 6 operates the shift fork 24 and the shift gear 16, and the shift fork 25 and the shift gear 17, as described below.

The state shown in Figures 2 and 3 is when the gearshift lever 6 is operated to the neutral position N1, the shift gear 16 is operated to a position where it does not engage with the transmission gear 18 and the shift gear 17, and the shift gear 17 is operated to a position where it does not engage with the transmission gears 18 and 20. In this state, the power of the input shaft 8 is not transmitted to the wheels 1, and the wheels 1 are stopped.

When the gearshift lever 6 is moved from the neutral position N1 to the first forward gear position F1, the gearshift lever 6 operates the shift fork 24, and the shift gear 16 is moved to a position where it engages with the transmission gear 18. In this state, the power of the input shaft 8 is transmitted to the wheels 1 in first forward gear via the shift gear 16, transmission gear 18, transmission shaft 14, transmission gears 19 and 20, transmission shaft 15, and transmission chain 22.

When the shift lever 6 is operated from the neutral position N1 to the intermediate position N2, the shift fork 24 is operated by the shift lever 6, and the shift gear 16 is operated to a position where it engages with the shift gear 17. When the shift lever 6 is operated from the intermediate position N2 to the intermediate position N3, the shift fork 25 can be operated by the shift lever 6, with the shift gear 16 held in a position where it engages with the shift gear 17.

When the gearshift lever 6 is moved from intermediate position N3 to second forward gear position F2, the gearshift lever 6 operates the shift fork 25, and the shift gear 17 is moved to a position where it engages with the transmission gear 20 while maintaining meshing with the shift gear 16. In this state, the power of the input shaft 8 is transmitted to the wheels 1 in second forward gear via the shift gears 16 and 17, transmission gear 20, transmission shaft 15, and transmission chain 22.

When the gearshift lever 6 is moved from intermediate position N3 to reverse position R1, the gearshift lever 6 operates the shift fork 25, and the shift gear 17 is moved to a position where it engages with the transmission gear 18 while maintaining meshing with the shift gear 16. In this state, the power of the input shaft 8 is transmitted to the wheels 1 in reverse via the shift gears 16 and 17, transmission gear 18, transmission shaft 14, transmission gears 19 and 20, transmission shaft 15, and transmission chain 22.

(Configuration and operation of forward/reverse rotation device)
As shown in FIG. 2, the forward/reverse rotation device 12 is configured as described below to transmit forward rotation power and reverse rotation power to the drive shaft 11, and is operated by the speed change lever 6.

The transmission gears 27 and 28 are connected to rotate integrally, and the transmission gears 27 and 28 are rotatably supported on the transmission shaft 13. The transmission gears 29 and 30 are connected to rotate integrally, and the transmission gears 29 and 30 are rotatably supported on the transmission shaft 14, and the transmission gears 28 and 30 are in mesh with each other.
A working clutch 31 is provided between the transmission shaft 13 and the transmission gears 27 and 28 , and a transmission chain 32 is attached between the transmission shaft 13 and the drive shaft 11 .

The shift gear 33 is supported by a spline structure so that it can rotate and slide integrally with the input shaft 8, and a shift fork 34 is provided to slide the shift gear 33. The shift fork 34 operates the shift gear 33 to three positions: a position in which it engages with the transmission gear 27, a position in which it engages with the transmission gear 29, and a position in which it does not engage with the transmission gears 27 and 29.

As shown in Figures 2 and 3, when the shift lever 6 is operated from the neutral position N1 to the first forward gear position F1, and then from the first forward gear position F1 to the stop position N4, the shift fork 34 can be operated by the shift lever 6 while the shift gear 16 is held in a position where it engages with the transmission gear 18.

When the gearshift lever 6 is operated to first forward gear position F1 and stop position N4, the shift gear 33 is operated to a position (stop position N4) where it does not engage with the transmission gears 27 and 29, and the power of the input shaft 8 is not transmitted to the drive shaft 11, causing the drive shaft 11 to stop.

When the speed change lever 6 is moved from the stop position N4 to the forward rotation position S11, the speed change lever 6 operates the shift fork 34, and the shift gear 33 is moved to a position where it engages with the transmission gear 29. In this state, the power of the input shaft 8 is transmitted to the drive shaft 11 in the forward rotation state via the shift gear 33, transmission gears 29, 30, transmission gears 27, 28, working clutch 31, transmission shaft 13, and transmission chain 32. In the forward rotation state, the drive shaft 11 is driven to rotate in the forward rotation direction S12, which is the clockwise direction in Figure 1.

When the speed change lever 6 is moved from the stop position N4 to the reverse position G11, the speed change lever 6 operates the shift fork 34, and the shift gear 33 is moved to a position where it engages with the transmission gear 27. In this state, the power of the input shaft 8 is transmitted in reverse to the drive shaft 11 via the shift gear 33, transmission gears 27 and 28, working clutch 31, transmission shaft 13, and transmission chain 32. In the reverse state, the drive shaft 11 is driven to rotate in the reverse direction G12, which is the counterclockwise direction in Figure 1.

(Configuration of tillage equipment)
As shown in Figures 1 and 4, the tillage implement 7 has a first claw shaft portion 35, a first tillage tine 36, a second claw shaft portion 37, a second tillage tine 38, and the like.

The claw shafts 35 and 37 are configured in the shape of a round pipe, with two mounting holes 35a and 35b opening radially in the claw shaft 35 and two mounting holes 37a and 37b opening radially in the claw shaft 37.

A large-diameter, disc-shaped operating unit 40 and cover 39 are connected to one end of the claw shafts 35, 37, and a small-diameter, disc-shaped operating unit 41 and cover 39 are connected to the other end of the claw shafts 35, 37.

At the claw shaft portion 35, the tillage tines 36 are attached to the claw shaft portion 35 in an orientation facing the operating unit 40. At the claw shaft portion 37, the tillage tines 38 are attached to the claw shaft portion 37 in an orientation facing the operating unit 41.

Mounting holes 11a, 11b are opened radially on the right and left sides of the drive shaft 11. The claw shafts 35, 37 are inserted into the right and left sides of the drive shaft 11, and the connecting pin 42 is inserted through the mounting holes 35a, 35b, 37a, 37b of the claw shafts 35, 37 and the mounting holes 11a, 11b of the drive shaft 11, thereby connecting the claw shafts 35, 37 to the drive shaft 11.

With the above configuration, as shown in Figures 1 and 4, a tillage device 7 is provided, which has claw shafts 35, 37 attached to the drive shaft 11 and tillage tines 36, 38 attached to the claw shafts 35, 37, and is driven by the drive shaft 11. The tillage device 7 has a first claw shaft 35 attached to one of the right and left ends of the drive shaft 11, and a second claw shaft 37 attached to the other of the right and left ends of the drive shaft 11.

As shown in Figures 1 and 2, the tillage tines 36, 38 pass from the top to the front of the tine shafts 35, 37, penetrate the ground, pushing the soil rearward. The drive shaft 11 is rotated in the forward direction S12, and this drives the drive shaft 11. The power is transmitted to the forward rotation position S11, and to a stop position N4, where the power to the drive shaft 11 is cut off.

(Installation on the drive shaft of the tillage equipment) - 1
In the tillage device 7, the claw shaft portions 35, 37 can be attached to the drive shaft 11 by selecting one of four mounting positions: reverse and inward, reverse and outward, forward and inward, and forward and outward, as described below.

As shown in Figures 4 and 10, the claw shaft portion 35 is inserted into the right portion of the drive shaft 11 from the operating portion 40 side, and the claw shaft portion 37 is inserted into the left portion of the drive shaft 11 from the operating portion 41 side. The connecting pin 42 is then inserted through the mounting holes 35a, 37a of the claw shaft portions 35, 37 and the mounting holes 11a, 11b of the drive shaft 11, thereby connecting the claw shaft portions 35, 37 to the drive shaft 11.

In the state shown in FIG. 10, the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted position and an inward position.
The reverse orientation is an orientation in which the radially outward portions of the tillage tines 36, 38 from the tine shaft portions 35, 37 are positioned downstream in the forward rotation direction S12.
The inward facing position is a position in which the tillage tines 36, 38 face toward the center of the left and right of the tillage implement 7 (toward the transmission case 2) when viewed from the rear (front).

As shown in Figures 4 and 11, the claw shaft portion 35 is inserted into the left portion of the drive shaft 11 from the operating portion 41 side, and the claw shaft portion 37 is inserted into the right portion of the drive shaft 11 from the operating portion 40 side. The connecting pin 42 is then inserted through the mounting holes 35b and 37b of the claw shaft portions 35 and 37 and the mounting holes 11a and 11b of the drive shaft 11, thereby connecting the claw shaft portions 35 and 37 to the drive shaft 11.

In the state shown in FIG. 11, the claw shaft portions 35 and 37 are attached to the drive shaft 11 in an inverted position and an outward position.
The outward orientation is an orientation in which the tillage tines 36, 38 face outward relative to the left-right center of the tillage implement 7 (transmission case 2) when viewed from the rear (front).

As shown in Figures 4 and 14, the claw shaft portion 35 is inserted into the left portion of the drive shaft 11 from the operating portion 40 side, and the claw shaft portion 37 is inserted into the right portion of the drive shaft 11 from the operating portion 41 side. The connecting pin 42 is then inserted through the mounting holes 35a, 37a of the claw shaft portions 35, 37 and the mounting holes 11a, 11b of the drive shaft 11, thereby connecting the claw shaft portions 35, 37 to the drive shaft 11.

In the state shown in FIG. 14, the claw shaft portions 35 and 37 are attached to the drive shaft 11 in a forward orientation and an inward orientation.
The forward orientation is an orientation in which the portions of the tillage tines 36, 38 that are radially outward from the tine shaft portions 35, 37 are positioned upstream in the forward rotation direction S12.

As shown in Figures 4 and 15, the claw shaft portion 35 is inserted into the right part of the drive shaft 11 from the operating portion 41 side, the claw shaft portion 37 is inserted into the left part of the drive shaft 11 from the operating portion 40 side, and the connecting pin 42 is inserted through the mounting holes 35b, 37b of the claw shaft portions 35, 37 and the mounting holes 11a, 11b of the drive shaft 11, thereby connecting the claw shaft portions 35, 37 to the drive shaft 11.
In the state shown in FIG. 15, the claw shaft portions 35 and 37 are attached to the drive shaft 11 in a forward orientation and an outward orientation.

(Installation on the drive shaft of the tillage equipment) - 2
With the above configuration, as shown in Figures 10, 11, 14, and 15, in the tillage device 7, the claw shaft portions 35, 37 can be attached to the drive shaft 11 in a forward position in which the portion of the tillage tines 36, 38 that is radially outward from the claw shaft portions 35, 37 is located upstream of the forward rotation direction S12, and in a reverse position in which the portion of the tillage tines 36, 38 that is radially outward from the claw shaft portions 35, 37 is located downstream of the forward rotation direction S12.

The first claw shaft portion 35 and the second claw shaft portion 37 can be attached to the drive shaft 11 in either an inward position where the tillage tines 36, 38 face toward the center of the tillage device 7 in a rear view, or an outward position where the tillage tines 36, 38 face outward from the center of the tillage device 7 in a rear view.

(Configuration of the claw shaft blocking member)
As shown in Figures 5, 8, and 9, a fulcrum shaft 43 is provided at the rear of the transmission case 2, above the drive shaft 11, and a channel-shaped operating member 44 is supported on the fulcrum shaft 43 so as to be swingable around an axis P1 along the fulcrum shaft 43.

The right claw shaft blocking member 45 (corresponding to the restraining unit, posture detection unit, and claw shaft restraining unit) is supported on the right side of the rear of the transmission case 2 so as to be slidable in the left-right direction, and the right claw shaft blocking member 45 is connected to the operating member 44.

An operating member 47 is supported on the fulcrum shaft 43 so as to be swingable around the axis P1. A left pawl shaft blocking member 46 (corresponding to the restraining unit, posture detection unit, and pawl shaft restraining unit) is supported on the left rear portion of the transmission case 2 so as to be slidable in the left-right direction. A connecting pin 48 is attached across the operating members 44, 47 and the left pawl shaft blocking member 46.

In the state shown in Figures 8 and 9, the right and left claw shaft blocking members 45, 46 are positioned in the installation blocking position A11, protruding outward from the transmission case 2, and can be moved to the installation allowable position A12, retracted into the transmission case 2.

The right and left claw shaft blocking members 45, 46 are connected by operating members 44, 47 and a connecting pin 48. As a result, when one of the right and left claw shaft blocking members 45, 46 is operated to the installation blocking position A11, the other of the right and left claw shaft blocking members 45, 46 is also operated to the installation blocking position A11 via the operating members 44, 47 and the connecting pin 48.

Similarly, when one of the right and left claw shaft blocking members 45, 46 is operated to the installation allowable position A12, the other of the right and left claw shaft blocking members 45, 46 is operated to the installation allowable position A12 via the operating members 44, 47 and the connecting pin 48.

(Relationship between the claw shaft blocking member and the operating portion of the claw shaft portion)
As shown in Figures 8 and 9, the right and left claw shaft blocking members 45, 46 are provided so that the length L1 from the axis P3 of the drive shaft 11 to the right claw shaft blocking member 45 is longer than the length L2 from the axis P3 of the drive shaft 11 to the left claw shaft blocking member 46.

As shown in FIG. 4, the operating portions 40, 41 are disk-shaped and are provided around the entire circumference of the claw shaft portions 35, 37 in the circumferential direction.
As shown in Figure 8, in the disk-shaped operating units 40 and 41, the radius RR1 of the operating unit 40 (the length from the axis P3 of the drive shaft 11 to the end of the outer periphery of the operating unit 40) is set to be larger than the lengths L1 and L2.

A recess 40a (corresponding to an avoidance portion) facing the left-right center of the claw shaft portions 35, 37 is provided around the entire circumference of the operating portion 40 at a length L2 from the center of the claw shaft portions 35, 37. The recess 40a is ring-shaped and is formed around the entire circumference of the operating portion 40.

As shown in Figure 8, the radius RR2 of the operating part 41 (the length from the axis P3 of the drive shaft 11 to the end of the outer periphery of the operating part 41) is set to be smaller than the length L1 and larger than the length L2. As a result, the outer periphery of the operating part 41 serves as an avoidance part, and the outer periphery of the operating part 41 (avoidance part) is formed around the entire circumferential circumference of the operating part 41.

When the pawl shaft portions 35, 37 are inserted into the right portion of the drive shaft 11 from the operating portion 40 side, the outer periphery of the operating portion 40 abuts the right pawl shaft blocking member 45, causing the right pawl shaft blocking member 45 to move from the installation blocking position A11 to the installation allowance position A12.

When the pawl shaft portions 35, 37 are inserted into the right portion of the drive shaft 11 from the operating portion 41 side, the outer periphery of the operating portion 41 enters below the right pawl shaft blocking member 45, preventing the right pawl shaft blocking member 45 from being moved to the allowable installation position A12.

When the claw shaft portions 35, 37 are inserted into the left portion of the drive shaft 11 from the operating portion 40 side, the left claw shaft blocking member 46 fits into the recess 40a of the operating portion 40, preventing the left claw shaft blocking member 46 from being moved to the allowable installation position A12.

When the pawl shaft portions 35, 37 are inserted into the left portion of the drive shaft 11 from the operating portion 41 side, the outer periphery of the operating portion 41 abuts the left pawl shaft blocking member 46, causing the left pawl shaft blocking member 46 to move from the installation blocking position A11 to the installation allowable position A12.

(Configuration of operation of the speed change lever to the forward rotation position and reverse rotation position)
As shown in Figures 5, 6, and 7, a shift shaft 49 is provided in the upper front part of the transmission case 2, above the input shaft 8, and extends in the left-right direction. The shift fork 34 (see Figure 2) is supported by the shift shaft 49 so as to be slidable in the left-right direction.

The engagement portion 34a extends upward from the shift fork 34. When the shift lever 6 is moved from first forward gear position F1 to stop position N4 (see Figure 3), the lower part of the shift lever 6 engages with the engagement portion 34a of the shift fork 34.

When the shift lever 6 is moved from the stop position N4 to the forward rotation position S11 (see Figure 3), the shift fork 34 is slid to the left in Figure 7 by the shift lever 6, and the shift gear 33 is moved to a position where it engages with the transmission gear 29 (see Figure 2).

When the shift lever 6 is moved from the stop position N4 to the reverse position G11 (see Figure 3), the shift fork 34 is slid to the right in Figure 7 by the shift lever 6, and the shift gear 33 is moved to a position where it engages with the transmission gear 27 (see Figure 2).

(Configuration of forward rotation prevention member)
As shown in Figures 5, 6, and 7, a shaft-shaped forward rotation preventing member 50 (corresponding to the restraining portion, forward rotation detecting portion, and forward rotation restraining portion) is provided in the upper front portion of the transmission case 2, above the engaging portion 34a of the shift fork 34, along the left-right direction, and is supported rotatably around an axis P2 that also extends in the left-right direction.

An arm 50a is connected to the right end of the forward rotation preventing member 50, and an arm 50b is connected to the left end of the forward rotation preventing member 50. The state shown in Figures 6 and 7 shows the forward rotation preventing member 50 in a state where it has been operated to a forward rotation permitted position B12, where the arm 50a of the forward rotation preventing member 50 is positioned above the engagement portion 34a of the shift fork 34 in a side view.

When the speed change lever 6 (shift fork 34) is operated to the stop position N4 or the reverse position G11, the forward rotation blocking member 50 can be rotated slightly clockwise in Figure 6 to move the forward rotation blocking member 50 to the forward rotation blocking position B11, where the arm 50a of the forward rotation blocking member 50 overlaps with the engagement portion 34a of the shift fork 34 in a side view. A spring 51 is attached to the forward rotation blocking member 50, and the spring 51 biases the forward rotation blocking member 50 to the forward rotation permitted position B12.

With the forward rotation preventing member 50 operated to the forward rotation allowing position B12, the speed change lever 6 (shift fork 34) can be operated to the forward rotation position S11 (see FIG. 3).
When the forward rotation preventing member 50 is operated to the forward rotation allowable position B12 and the speed change lever 6 (shift fork 34) is operated to the forward rotation position S11 (operated to the left in Figure 7), the engaging portion 34a of the shift fork 34 enters below the arm 50a of the forward rotation preventing member 50 at the forward rotation allowable position B12.

When the above-described state is reached, even if the forward rotation blocking member 50 is attempted to be moved from the forward rotation permitted position B12 to the forward rotation blocked position B11, the arm 50a of the forward rotation blocking member 50 will come into contact with the engagement portion 34a of the shift fork 34. As a result, the forward rotation blocking member 50 cannot be moved from the forward rotation permitted position B12 to the forward rotation blocked position B11, and is instead held in the forward rotation permitted position B12.

When the forward rotation blocking member 50 is operated to the forward rotation blocking position B11 while the shift lever 6 (shift fork 34) is operated to the stop position N4 or reverse position G11, the engaging portion 34a of the shift fork 34 will come into contact with the arm 50a of the forward rotation blocking member 50 even if the shift lever 6 (shift fork 34) is operated to the forward rotation position S11.

As a result, the forward rotation blocking member 50 cannot be moved from the forward rotation permitted position B12 to the forward rotation blocked position B11, and the speed change lever 6 (shift fork 34) cannot be moved from the stop position N4 to the forward rotation position S11.

(Configuration of the linking member connected across the forward rotation preventing member and the pawl shaft preventing member)-1
As shown in FIGS. 5 to 9, a rod-shaped linking member 52 is connected within the transmission case 2 across the arm 50 b of the forward rotation preventing member 50 and the operating member 47 of the claw shaft preventing members 45 , 46 .

The state shown in Figures 6 to 9 is one in which the forward rotation preventing member 50 is operated by the spring 51 to the forward rotation permitted position B12, the forward rotation preventing member 50 pulls the linking member 52 forward (towards the forward rotation preventing member 50), and the pawl shaft preventing members 45, 46 are operated to the attachment preventing position A11.

As described below, when the claw shaft portions 35, 37 are attached to the drive shaft 11 in the reverse and inward orientations (reverse and outward orientations), the operating portions 40, 41 of the claw shaft portions 35, 37 operate the claw shaft blocking members 45, 46 from the attachment blocking position A11 to the attachment allowance position A12.

When the claw shaft blocking members 45, 46 are operated from the mounting blocking position A11 to the mounting allowable position A12, the claw shaft blocking members 45, 46 detect that the claw shaft portions 35, 37 are mounted on the drive shaft 11 in the reverse and inward orientations (reverse and outward orientations).

In the state shown in Figures 6 to 9, when the claw shaft blocking members 45, 46 are moved from the installation blocking position A11 to the installation allowable position A12, the linking member 52 is pulled rearward (toward the claw shaft blocking members 45, 46), and the forward rotation blocking member 50 is moved from the forward rotation allowable position B12 to the forward rotation blocking position B11.

In the state shown in Figures 6 to 9, when the speed change lever 6 (shift fork 34) is operated to the forward rotation position S11, the engagement portion 34a of the shift fork 34 enters below the arm 50a of the forward rotation blocking member 50 in the forward rotation permitted position B12, and the forward rotation blocking member 50 cannot be operated to the forward rotation blocked position B11 (the forward rotation blocking member 50 is held in the forward rotation permitted position B12).

Because the forward rotation preventing member 50 cannot be moved from the forward rotation allowing position B12 to the forward rotation preventing position B11, the forward rotation preventing member 50 detects that the speed change lever 6 (shift fork 34) has been moved to the forward rotation position S11 and that the forward/reverse rotation device 12 has been moved to the forward rotation position S11.

When the forward rotation preventing member 50 is held in the forward rotation allowing position B12, the pawl shaft preventing members 45, 46 are held in the mounting preventing position A11 via the linking member 52.
When the claw shaft blocking members 45, 46 are held in the mounting blocking position A11, as described below, the claw shaft blocking members 45, 46 prevent the claw shaft portions 35, 37 from being mounted on the drive shaft 11 in the reverse and inward positions (reverse and outward positions).

(Configuration of the linking member connected across the forward rotation preventing member and the pawl shaft preventing member)-2
With the above configuration, as shown in Figures 5 to 9, the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted position, and restraining portions (claw shaft blocking members 45, 46 and forward rotation blocking member 50) are provided to prevent the transmission device (forward/reverse rotation device 12) from being operated to the forward rotation position S11.

The restraining unit (claw shaft blocking members 45, 46 and forward rotation blocking member 50) has an attitude detection unit (claw shaft blocking members 45, 46) that detects when the claw shafts 35, 37 are attached to the drive shaft 11 in a reverse orientation, and a forward rotation restraining unit (forward rotation blocking member 50) that prevents the transmission device (forward/reverse rotation device 12) from being operated to the forward rotation position S11 when the attitude detection unit (claw shaft blocking members 45, 46) detects that the claw shafts 35, 37 are attached to the drive shaft 11 in a reverse orientation.

It is equipped with a right posture detection unit (right pawl shaft blocking member 45) that detects when the pawl shafts 35, 37 are attached to the right side of the drive shaft 11 in an inverted position, and a left posture detection unit (left pawl shaft blocking member 46) that detects when the pawl shafts 35, 37 are attached to the left side of the drive shaft 11 in an inverted position.

The restraining unit (claw shaft blocking members 45, 46 and forward rotation blocking member 50) has a forward rotation detection unit (forward rotation blocking member 50) that detects when the transmission device (forward/reverse rotation device 12) has been operated to the forward rotation position S11, and a claw shaft restraining unit (claw shaft blocking members 45, 46) that prevents the claw shafts 35, 37 from being attached to the drive shaft 11 in a reverse position when the forward rotation detection unit (forward rotation blocking member 50) detects that the transmission device (forward/reverse rotation device 12) has been operated to the forward rotation position S11.

When the forward rotation detection unit (forward rotation prevention member 50) detects that the transmission device (forward/reverse rotation device 12) has been operated to the forward rotation position S11, the claw shaft restraint unit (claw shaft blocking members 45, 46) prevents the claw shafts 35, 37 from being attached to the right side of the drive shaft 11 in the reverse position, and also prevents the claw shafts 35, 37 from being attached to the left side of the drive shaft 11 in the reverse position.

The restraining unit (claw shaft blocking members 45, 46 and forward rotation blocking member 50) comprises a posture detection unit (claw shaft blocking members 45, 46) that detects when the claw shafts 35, 37 are attached to the drive shaft 11 in a reverse posture, a forward rotation detection unit (forward rotation blocking member 50) that detects when the transmission device (forward/reverse rotation device 12) is operated to the forward rotation position S11, and a posture detection unit (claw shaft blocking members 45, 46) that detects when the claw shafts 35, 37 are attached to the drive shaft 11 in a reverse posture. The device has a forward rotation inhibiting section (forward rotation inhibiting member 50) that prevents the transmission device (forward/reverse rotation device 12) from being moved to the forward rotation position S11 when it detects that the device has been attached, and a pawl shaft inhibiting section (pawl shaft inhibiting members 45, 46) that prevents the pawl shaft sections 35, 37 from being attached to the drive shaft 11 in a reverse position when the forward rotation detecting section (forward rotation inhibiting member 50) detects that the transmission device (forward/reverse rotation device 12) has been moved to the forward rotation position S11.

(Configuration of the linking member connected across the forward rotation preventing member and the claw shaft preventing member)-3
With the above configuration, as shown in Figures 5 to 9, claw shaft blocking members 45, 46 are provided that can be operated to an attachment blocking position A11 that prevents the claw shaft portions 35, 37 from being attached to the drive shaft 11, and an attachment allowing position A12 that allows the claw shaft portions 35, 37 to be attached to the drive shaft 11.

A forward rotation blocking member 50 is provided that can be operated to a forward rotation blocking position B11, which prevents the transmission device (forward/reverse rotation device 12) from being moved to the forward rotation position S11, and a forward rotation allowing position B12, which allows the transmission device (forward/reverse rotation device 12) to be moved to the forward rotation position S11 and prevents it from being moved to the forward rotation blocking position B11 when the transmission device (forward/reverse rotation device 12) is moved to the forward rotation position S11.

Operating units 40, 41 are provided on the claw shaft portions 35, 37. When the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted position, they come into contact with the claw shaft blocking members 45, 46, thereby operating the claw shaft blocking members 45, 46 to the allowable attachment position A12.

A linking member 52 is provided that connects the normal rotation preventing member 50 and the pawl shaft preventing members 45 and 46 across the linking member 52 .
When the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted position, the claw shaft blocking members 45, 46 are operated to the attachment allowance position A12 by the operating portions 40, 41, and the forward rotation blocking member 50 is operated to the forward rotation blocking position B11 via the linking member 52.

When the forward rotation preventing member 50 is operated to the forward rotation allowing position B12, the claw shaft preventing members 45, 46 are operated to the attachment preventing position A11 via the linking member 52, and when the transmission device (forward/reverse rotation device 12) is operated to the forward rotation position S11, the claw shaft preventing members 45, 46 are held in the attachment preventing position A11 via the forward rotation preventing member 50 and the linking member 52.
The claw shaft blocking members 45 and 46 are posture detection units and claw shaft restraining units, and the normal rotation blocking member 50 is a normal rotation detection unit and a normal rotation restraining unit.

(In the tillage equipment, the state after the tine shaft part is attached to the drive shaft in the reverse position and inward position, and the reverse position and outward position) - 1
As shown in Figures 4, 8, and 10, when the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted position and an inward position, when the claw shaft portion 35 is inserted into the right part of the drive shaft 11 from the operating portion 40 side, the operating portion 40 of the claw shaft portion 35 abuts against the right claw shaft blocking member 45, and the right claw shaft blocking member 45 is operated to the installation allowable position A12. In conjunction with this, the left claw shaft blocking member 46 is operated to the installation allowable position A12.

When the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted or inward orientation, when the claw shaft portion 37 is inserted into the left portion of the drive shaft 11 from the operating portion 41 side, the operating portion 41 of the claw shaft portion 37 abuts the left claw shaft blocking member 46, causing the left claw shaft blocking member 46 to be operated to the allowable installation position A12, and in conjunction with this, the right claw shaft blocking member 45 is operated to the allowable installation position A12.

As shown in Figures 4, 8, and 11, when the claw shaft portions 35, 37 are attached to the drive shaft 11 in the inverted and outward orientations, when the claw shaft portion 35 is inserted into the left portion of the drive shaft 11 from the operating portion 41 side, the operating portion 41 of the claw shaft portion 35 abuts the left claw shaft blocking member 46, causing the left claw shaft blocking member 46 to be operated to the installation allowable position A12, and in conjunction with this, the right claw shaft blocking member 45 is operated to the installation allowable position A12.

When the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted or outward orientation, when the claw shaft portion 37 is inserted into the right part of the drive shaft 11 from the operating portion 40 side, the operating portion 40 of the claw shaft portion 37 abuts the right claw shaft blocking member 45, causing the right claw shaft blocking member 45 to be operated to the installation allowable position A12, and in conjunction with this, the left claw shaft blocking member 46 is operated to the installation allowable position A12.

Since the operating units 40, 41 are formed in a disk shape, the operating units 40, 41 will come into contact with the claw shaft blocking members 45, 46 regardless of whether the claw shaft units 35, 37 are attached to the drive shaft 11 in a reverse or inward orientation and at any phase in the rotational direction of the drive shaft 11, or whether the claw shaft units 35, 37 are attached to the drive shaft 11 in a reverse or outward orientation and at any phase in the rotational direction of the drive shaft 11.

As described above, when the claw shaft blocking members 45, 46 are operated to the installation allowable position A12, the forward rotation blocking member 50 is operated to the forward rotation blocking position B11 via the linkage member 52, so that the speed change lever 6 (shift fork 34) cannot be operated to the forward rotation position S11 and the forward/reverse rotation device 12 cannot be operated to the forward rotation position S11.
In this case, it is possible to operate the speed change lever 6 (shift fork 34) to the reverse position G11, and the forward/reverse rotation device 12 to the reverse position G11.

(In the tillage equipment, the state after the tines are attached to the drive shaft in the reverse and inward positions, and the reverse and outward positions) - 2
With the above-described configuration, as shown in FIGS. 4 and 8, the operating units 40, 41 are provided around the entire circumferential direction of the claw shaft portions 35, 37, and come into contact with the claw shaft blocking members 45, 46 regardless of the phase in the rotational direction of the drive shaft 11 when the claw shaft portions 35, 37 are attached in an inverted orientation.

As shown in Figures 10 and 11, when the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted or inward position, the operating units 40, 41 come into contact with the claw shaft blocking members 45, 46, thereby operating the claw shaft blocking members 45, 46 to the allowable attachment position A12.Furthermore, when the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted or outward position, the operating units 40, 41 come into contact with the claw shaft blocking members 45, 46, thereby operating the claw shaft blocking members 45, 46 to the allowable attachment position A12.

The operating units 40, 41 are provided around the entire circumference of the claw shafts 35, 37, and will come into contact with the claw shaft blocking members 45, 46 regardless of whether the claw shafts 35, 37 are attached to the drive shaft 11 in a reverse or inward orientation and at any phase in the rotational direction of the drive shaft 11, or whether the claw shafts 35, 37 are attached to the drive shaft 11 in a reverse or outward orientation and at any phase in the rotational direction of the drive shaft 11.

The posture detection unit (claw shaft blocking members 45, 46) detects when the claw shafts 35, 37 are attached to the drive shaft 11 in an inverted or inward position, and also detects when the claw shafts 35, 37 are attached to the drive shaft 11 in an inverted or outward position.

When the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted and inward position, the claw shaft blocking members 45, 46 are operated to the attachment allowance position A12 by the operating portions 40, 41, and the forward rotation blocking member 50 is operated to the forward rotation blocking position B11 via the connecting member 52.
When the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted and outward position, the claw shaft blocking members 45, 46 are operated to the attachment allowance position A12 by the operating portions 40, 41, and the forward rotation blocking member 50 is operated to the forward rotation blocking position B11 via the connecting member 52.

The forward rotation restraint unit (forward rotation blocking member 50) prevents the transmission device (forward/reverse rotation device 12) from being moved to the forward rotation position S11 when at least one of the following conditions is detected: the right attitude detection unit (right claw shaft blocking member 45) detects that the claw shafts 35, 37 are attached to the right portion of the drive shaft 11 in a reverse orientation; or the left attitude detection unit (left claw shaft blocking member 46) detects that the claw shafts 35, 37 are attached to the left portion of the drive shaft 11 in a reverse orientation.

A right claw shaft blocking member 45 is provided which can be operated to an attachment blocking position A11 which prevents the attachment of the claw shaft portions 35, 37 to the right portion of the drive shaft 11, and an attachment allowing position A12 which allows the attachment of the claw shaft portions 35, 37 to the right portion of the drive shaft 11.
A left claw shaft blocking member 46 is provided which can be operated to an attachment blocking position A11 which prevents the claw shaft portions 35, 37 from being attached to the left portion of the drive shaft 11, and an attachment allowing position A12 which allows the claw shaft portions 35, 37 to be attached to the left portion of the drive shaft 11.
When the right claw shaft blocking member 45 is operated to the installation allowable position A12 and/or the left claw shaft blocking member 46 is operated to the installation allowable position A12, the forward rotation preventing member 50 is operated to the forward rotation preventing position B11 via the linking member 52.

When the transmission device (forward/reverse rotation device 12) is operated to the forward rotation position S11, the right claw shaft blocking member 45 and the left claw shaft blocking member 46 are held in the mounting blocking position A11 via the forward rotation blocking member 50 and the linking member 52.

(In the tillage device, the state after the forward/reverse rotation device is operated to the forward rotation position)
As shown in Figure 12, when the forward rotation preventing member 50 is operated to the forward rotation allowing position B12, the speed change lever 6 (shift fork 34) is operated to the forward rotation position S11, and the forward/reverse rotation device 12 is operated to the forward rotation position S11, the engaging portion 34a of the shift fork 34 enters below the arm 50a of the forward rotation preventing member 50.
As a result, the forward rotation preventing member 50 is held in the forward rotation allowing position B12, and the claw shaft preventing members 45, 46 are held in the mounting preventing position A11 via the forward rotation preventing member 50 and the linking member 52.

As shown in Figures 4, 8, and 12, when the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted or inward orientation, when the claw shaft portion 35 is inserted into the right portion of the drive shaft 11 from the operating portion 40 side, the operating portion 40 of the claw shaft portion 35 hits the right claw shaft blocking member 45, and the claw shaft portion 35 cannot be inserted any further into the right portion of the drive shaft 11.

When the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted or inward orientation, if the claw shaft portion 37 is inserted into the left portion of the drive shaft 11 from the operating portion 41 side, the operating portion 41 of the claw shaft portion 37 will hit the left claw shaft blocking member 46, preventing the claw shaft portion 37 from being inserted any further into the left portion of the drive shaft 11.

As shown in Figures 4, 8, and 13, when the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted or outward orientation, when the claw shaft portion 35 is inserted into the left portion of the drive shaft 11 from the operating portion 41 side, the operating portion 41 of the claw shaft portion 35 hits the left claw shaft blocking member 46, and the claw shaft portion 35 cannot be inserted any further into the left portion of the drive shaft 11.

When the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted or inward orientation, if the claw shaft portion 37 is inserted into the right portion of the drive shaft 11 from the operating portion 40 side, the operating portion 40 of the claw shaft portion 37 will hit the right claw shaft blocking member 45, preventing the claw shaft portion 37 from being inserted any further into the right portion of the drive shaft 11.

As mentioned above, when the operating portions 40, 41 of the claw shaft portions 35, 37 are in contact with the claw shaft blocking members 45, 46 held in the mounting blocking position A11, the positions of the mounting holes 35a, 35b, 37a, 37b of the claw shaft portions 35, 37 shown in Figure 4 do not match the positions of the mounting holes 11a, 11b of the drive shaft 11.

As a result, the connecting pin 42 cannot be inserted through the mounting holes 35a, 35b, 37a, and 37b of the claw shafts 35 and 37 and the mounting holes 11a and 11b of the drive shaft 11, and the claw shafts 35 and 37 cannot be connected to the drive shaft 11.

(In the tillage equipment, the state in which the tines are attached to the drive shaft in a forward position and an inward position, and a forward position and an outward position) -1
As shown in Figures 4, 8, and 14, when the claw shaft portion 35 is inserted into the left part of the drive shaft 11 from the side of the operating portion 40 and the claw shaft portion 37 is inserted into the right part of the drive shaft 11 from the side of the operating portion 41, the left claw shaft blocking member 46 enters the recess 40a of the operating portion 40 of the claw shaft portion 35, and the outer periphery of the operating portion 41 of the claw shaft portion 37 enters below the right claw shaft blocking member 45.

As a result, the positions of 35a, 37a of the claw shaft portions 35, 37 shown in Figure 4 coincide with the positions of the mounting holes 11a, 11b of the drive shaft 11, so the connecting pin 42 can be inserted through 35a, 37a of the claw shaft portions 35, 37 and the mounting holes 11a, 11b of the drive shaft 11, connecting the claw shaft portions 35, 37 to the drive shaft 11. This is the state in which the claw shaft portions 35, 37 are attached to the drive shaft 11 in a forward and inward orientation.

As shown in Figures 4, 8, and 15, when the claw shaft portion 35 is inserted into the right portion of the drive shaft 11 from the operating portion 41 side and the claw shaft portion 37 is inserted into the left portion of the drive shaft 11 from the operating portion 40 side, the outer periphery of the operating portion 41 of the claw shaft portion 35 enters below the right claw shaft blocking member 45, and the left claw shaft blocking member 46 enters the recess 40a of the operating portion 40 of the claw shaft portion 37.

As a result, the positions of 35b, 37b of the claw shaft portions 35, 37 coincide with the positions of the mounting holes 11a, 11b of the drive shaft 11, so the connecting pin 42 can be inserted through 35b, 37b of the claw shaft portions 35, 37 and the mounting holes 11a, 11b of the drive shaft 11, connecting the claw shaft portions 35, 37 to the drive shaft 11. This is the state in which the claw shaft portions 35, 37 are attached to the drive shaft 11 in a forward and outward orientation.

When the claw shaft portions 35, 37 are attached to the drive shaft 11 in a forward and inward orientation, and when the claw shaft portions 35, 37 are attached to the drive shaft 11 in a forward and outward orientation, the claw shaft blocking members 45, 46 are not operated to the attachment allowance position A12 (they remain in the attachment blocking position A11).

As a result, the forward rotation blocking member 50 is not operated to the forward rotation blocking position B11 and remains in the forward rotation allowing position B12, allowing the speed change lever 6 (shift fork 34) to be operated to the forward rotation position S11.

Conversely, suppose the speed change lever 6 (shift fork 34) is operated to the forward rotation position S11, the forward rotation blocking member 50 is held in the forward rotation permitted position B12, and the pawl shaft blocking members 45, 46 are held in the mounting blocking position A11.

In this state, when the claw shaft portions 35, 37 are attached to the drive shaft 11 in the forward and inward orientations (forward and outward orientations) as described above, the left claw shaft blocking member 46 fits into the recess 40a of the operating portion 40, and the outer periphery of the operating portion 41 fits below the right claw shaft blocking member 45. Therefore, regardless of the claw shaft blocking members 45, 46, the claw shaft portions 35, 37 are attached to the drive shaft 11 in the forward and inward orientations (forward and outward orientations).

The recess 40a of the operating unit 40 is ring-shaped and extends around the entire circumferential circumference of the operating unit 40. The outer periphery (avoidance portion) of the operating unit 41 extends around the entire circumferential circumference of the operating unit 41.

As a result, regardless of the phase in the rotational direction of the drive shaft 11 at which the claw shaft portions 35, 37 are attached in the forward or inward position, or regardless of the phase in the rotational direction of the drive shaft 11 at which the claw shaft portions 35, 37 are attached in the forward or outward position, the operating portions 40, 41 will not come into contact with the claw shaft blocking members 45, 46.

(In the tillage equipment, the state in which the tines are attached to the drive shaft in a forward position and an inward position, and a forward position and an outward position) -2
With the above-described configuration, as shown in Figures 8, 14, and 15, the operating units 40, 41 are provided with avoidance portions (recesses 40a) that prevent the operating units 40, 41 from hitting the claw shaft blocking members 45, 46 when the claw shaft units 35, 37 are attached to the drive shaft 11 in a forward position or an inward position, and that prevent the operating units 40, 41 from hitting the claw shaft blocking members 45, 46 when the claw shaft units 35, 37 are attached to the drive shaft 11 in a forward position or an outward position.

The avoidance portion (recess 40a) is provided around the entire circumference of the operating portions 40, 41, and prevents the operating portions 40, 41 from coming into contact with the claw shaft blocking members 45, 46 regardless of whether the claw shaft portions 35, 37 are attached to the drive shaft 11 in a forward or inward orientation and at any phase in the rotational direction of the drive shaft 11, or whether the claw shaft portions 35, 37 are attached to the drive shaft 11 in a forward or outward orientation and at any phase in the rotational direction of the drive shaft 11.

(First Alternative Embodiment of the Invention)
A posture detection sensor (not shown) (corresponding to a posture detection unit) may be provided to electrically detect that the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted posture.
In the above-described configuration, when the posture detection sensor detects that the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted posture, a forward rotation restraining actuator (not shown) (corresponding to the forward rotation restraining portion) may be provided which prevents the forward/reverse rotation device 12 (transmission device) from being operated to the forward rotation position S11.
As a result, the restraining section has an attitude detection sensor and a forward rotation restraining actuator.

(Second Alternative Embodiment of the Invention)
A forward rotation detection sensor (not shown) (corresponding to a forward rotation detection unit) may be provided to electrically detect that the forward/reverse rotation device 12 (transmission device) has been operated to the forward rotation position S11.
In the above-described configuration, a claw shaft restraining actuator (not shown) (corresponding to the claw shaft restraining portion) may be provided that prevents the claw shaft portions 35, 37 from being attached to the drive shaft 11 in the reverse orientation when the forward/reverse rotation device 12 (transmission device) is detected by the forward rotation detection sensor to be operated to the forward rotation position S11.
As a result, the restraining unit has a forward rotation detection sensor and a claw shaft restraining actuator.

(Third Alternative Embodiment of the Invention)
It is also possible to provide an attitude detection sensor (not shown) (corresponding to the attitude detection unit) that electrically detects that the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted attitude, and a forward rotation detection sensor (not shown) (corresponding to the forward rotation detection unit) that electrically detects that the forward/reverse rotation device 12 (transmission device) has been operated to the forward rotation position S11.

In the above-described configuration, a forward rotation restraint actuator (not shown) (corresponding to the forward rotation restraint unit) may be provided that prevents the forward/reverse rotation device 12 (transmission device) from being moved to the forward rotation position S11 when the posture detection sensor detects that the claw shafts 35, 37 are attached to the drive shaft 11 in the reverse posture.

When the forward/reverse rotation detection sensor detects that the forward/reverse rotation device 12 (transmission device) has been operated to the forward rotation position S11, a claw shaft restraining actuator (not shown) (corresponding to the claw shaft restraining portion) may be provided which prevents the claw shaft portions 35, 37 from being attached to the drive shaft 11 in the reverse orientation.
As a result, the restraining section has an attitude detection sensor, a normal rotation detection sensor, a normal rotation restraining actuator, and a claw shaft restraining actuator.

(Fourth Alternative Embodiment of the Invention)
Eight tillage tines 36, 38 may be attached to the tine shaft portions 35, 37, or four tillage tines 36, 38 may be attached to the tine shaft portions 35, 37.
Instead of the wheels 1, a crawler traveling device (not shown) may be provided as the traveling device.
An electric motor (not shown) may be provided as a driving unit instead of the engine 4. In this case, an electric motor for driving the wheels 1 and an electric motor for driving the tilling implement 7 may be provided separately.

The present invention can be applied to a walk-behind cultivator in which a tilling device is mounted at the rear of the machine body supported by a traveling device.

1. Wheels (running gear)
2 Transmission case (airframe)
7 tillage device 11 drive shaft 12 forward/reverse rotation device (transmission device)
35 Claw shaft portion 36 Tillage tine 37 Claw shaft portion 38 Tillage tine 40 Operating portion 40a Recessed portion (avoidance portion)
41 Operation unit 45 Claw shaft inhibiting member (restraint unit) (posture detection unit) (claw shaft restraint unit)
46 Claw shaft blocking member (restraint unit) (posture detection unit) (claw shaft restraint unit)
50 Normal rotation prevention member (restraint portion) (normal rotation detection portion) (normal rotation restraint portion)
52 Linking member A11 Mounting prevention position A12 Mounting allowable position B11 Forward rotation prevention position B12 Forward rotation allowable position N4 Stop position S11 Forward rotation position S12 Forward rotation direction

Claims (11)

a machine body supported by a running gear;
a drive shaft supported along the left-right direction at the rear of the aircraft body;
A tillage device having a claw shaft portion attached to the drive shaft and a tillage claw attached to the claw shaft portion and driven by the drive shaft;
a transmission device operable to a forward rotation position in which the drive shaft transmits power to rotate in a forward rotation direction in which the tillage tines pass from the upper side to the front side of the tine shaft portion, penetrate into the ground, and push soil on the ground rearward, to the drive shaft, and a stop position in which power to the drive shaft is cut off;
The claw shaft portion can be attached to the drive shaft in a forward orientation in which the portion of the tillage tine that is radially outward from the claw shaft portion is located on the upstream side of the normal rotation direction, and in a reverse orientation in which the portion of the tillage tine that is radially outward from the claw shaft portion is located on the downstream side of the normal rotation direction,
a restraining portion that prevents the occurrence of a state in which the claw shaft portion is attached to the drive shaft in the reverse orientation and the transmission device is operated to the normal rotation position ,
The restraining unit is
an attitude detection unit that detects that the claw shaft portion is attached to the drive shaft in the reverse attitude;
a forward rotation inhibiting unit that inhibits operation of the transmission device to the forward rotation position when the attitude detecting unit detects that the claw shaft unit is attached to the drive shaft in the reverse attitude,
a claw shaft blocking member operable to an attachment blocking position that blocks attachment of the claw shaft portion to the drive shaft and an attachment allowing position that allows attachment of the claw shaft portion to the drive shaft;
an operating portion that is provided on the claw shaft portion and that, when the claw shaft portion is attached to the drive shaft in the inverted position, comes into contact with the claw shaft blocking member, thereby operating the claw shaft blocking member to the attachment allowable position;
a forward rotation preventing member operable to a forward rotation preventing position that prevents operation of the transmission device to the forward rotation position, and a forward rotation allowing position that allows operation of the transmission device to the forward rotation position and prevents operation to the forward rotation preventing position when the transmission device is operated to the forward rotation position;
a linking member connected across the forward rotation preventing member and the pawl shaft preventing member,
When the claw shaft portion is attached to the drive shaft in the reverse orientation, the claw shaft blocking member is operated to the attachment allowance position by the operating portion, and the forward rotation blocking member is operated to the forward rotation blocking position via the linking member,
When the forward rotation preventing member is operated to the forward rotation allowing position, the claw shaft preventing member is operated to the attachment preventing position via the linking member, and when the transmission device is operated to the forward rotation position, the claw shaft preventing member is held at the attachment preventing position via the forward rotation preventing member and the linking member,
the claw shaft blocking member is the attitude detection unit,
The forward rotation prevention member is the forward rotation restraining part of the walking-type tiller. The tillage implement has a first claw shaft portion attached to one of the right and left portions of the drive shaft and a second claw shaft portion attached to the other of the right and left portions of the drive shaft,
a right attitude detection unit that detects that the claw shaft portion is attached to the right part of the drive shaft in the reverse attitude;
a left attitude detection unit that detects that the claw shaft portion is attached to the left part of the drive shaft in the reverse attitude,
The walk-behind cultivator of claim 1, wherein the forward rotation restraint unit prevents the transmission device from being operated to the forward rotation position when at least one of the right attitude detection unit detects that the claw shaft unit is attached to the right part of the drive shaft in the reverse attitude, and the left attitude detection unit detects that the claw shaft unit is attached to the left part of the drive shaft in the reverse attitude. The first claw shaft portion and the second claw shaft portion can be attached to the drive shaft in an inward position in which the tillage tines face the left-right central portion of the tillage device when viewed from behind, and in an outward position in which the tillage tines face outward from the left-right central portion of the tillage device when viewed from behind,
The walking-type cultivator according to claim 2, wherein the posture detection unit detects that the claw shaft portion is attached to the drive shaft in the reverse posture and the inward posture, and detects that the claw shaft portion is attached to the drive shaft in the reverse posture and the outward posture. a machine body supported by a running gear;
a drive shaft supported along the left-right direction at the rear of the aircraft body;
A tillage device having a claw shaft portion attached to the drive shaft and a tillage claw attached to the claw shaft portion and driven by the drive shaft;
a transmission device operable to a forward rotation position in which the drive shaft transmits power to rotate in a forward rotation direction in which the tillage tines pass from the upper side to the front side of the tine shaft portion, penetrate into the ground, and push soil on the ground rearward, to the drive shaft, and a stop position in which power to the drive shaft is cut off;
The claw shaft portion can be attached to the drive shaft in a forward orientation in which the portion of the tillage tine that is radially outward from the claw shaft portion is located on the upstream side of the normal rotation direction, and in a reverse orientation in which the portion of the tillage tine that is radially outward from the claw shaft portion is located on the downstream side of the normal rotation direction,
a restraining portion that prevents the occurrence of a state in which the claw shaft portion is attached to the drive shaft in the reverse orientation and the transmission device is operated to the normal rotation position ,
The restraining unit is
a normal rotation detection unit that detects that the transmission device is operated to the normal rotation position;
a claw shaft restraining portion that prevents the claw shaft portion from being attached to the drive shaft in the reverse orientation when the normal rotation detection portion detects that the transmission device has been operated to the normal rotation position,
a claw shaft blocking member operable to an attachment blocking position that blocks attachment of the claw shaft portion to the drive shaft and an attachment allowing position that allows attachment of the claw shaft portion to the drive shaft;
an operating portion that is provided on the claw shaft portion and that, when the claw shaft portion is attached to the drive shaft in the inverted position, comes into contact with the claw shaft blocking member, thereby operating the claw shaft blocking member to the attachment allowable position;
a forward rotation preventing member operable to a forward rotation preventing position that prevents operation of the transmission device to the forward rotation position, and a forward rotation allowing position that allows operation of the transmission device to the forward rotation position and prevents operation to the forward rotation preventing position when the transmission device is operated to the forward rotation position;
a linking member connected across the forward rotation preventing member and the pawl shaft preventing member,
When the claw shaft portion is attached to the drive shaft in the reverse orientation, the claw shaft blocking member is operated to the attachment allowance position by the operating portion, and the forward rotation blocking member is operated to the forward rotation blocking position via the linking member,
When the forward rotation preventing member is operated to the forward rotation allowing position, the claw shaft preventing member is operated to the attachment preventing position via the linking member, and when the transmission device is operated to the forward rotation position, the claw shaft preventing member is held at the attachment preventing position via the forward rotation preventing member and the linking member,
The claw shaft blocking member is the claw shaft restraining portion,
The forward rotation prevention member is the forward rotation detection unit of the walking-type cultivator. The tillage implement has a first claw shaft portion attached to one of the right and left portions of the drive shaft and a second claw shaft portion attached to the other of the right and left portions of the drive shaft,
The walking-type cultivator according to claim 4, wherein the claw shaft restraining unit prevents the claw shaft from being attached to the right side of the drive shaft in the reverse position when the forward rotation detection unit detects that the transmission device has been operated to the forward rotation position, and prevents the claw shaft from being attached to the left side of the drive shaft in the reverse position. a machine body supported by a running gear;
a drive shaft supported along the left-right direction at the rear of the aircraft body;
A tillage device having a claw shaft portion attached to the drive shaft and a tillage claw attached to the claw shaft portion and driven by the drive shaft;
a transmission device operable to a forward rotation position in which the drive shaft transmits power to rotate in a forward rotation direction in which the tillage tines pass from the upper side to the front side of the tine shaft portion, penetrate into the ground, and push soil on the ground rearward, to the drive shaft, and a stop position in which power to the drive shaft is cut off;
The claw shaft portion can be attached to the drive shaft in a forward orientation in which the portion of the tillage tine that is radially outward from the claw shaft portion is located on the upstream side of the normal rotation direction, and in a reverse orientation in which the portion of the tillage tine that is radially outward from the claw shaft portion is located on the downstream side of the normal rotation direction,
a restraining portion that prevents the occurrence of a state in which the claw shaft portion is attached to the drive shaft in the reverse orientation and the transmission device is operated to the normal rotation position ,
The restraining unit is
an attitude detection unit that detects that the claw shaft portion is attached to the drive shaft in the reverse attitude;
a normal rotation detection unit that detects that the transmission device is operated to the normal rotation position;
a forward rotation inhibiting unit that inhibits operation of the transmission device to the forward rotation position when the attitude detecting unit detects that the claw shaft unit is attached to the drive shaft in the reverse attitude;
a claw shaft restraining portion that prevents the claw shaft portion from being attached to the drive shaft in the reverse orientation when the normal rotation detection portion detects that the transmission device has been operated to the normal rotation position,
a claw shaft blocking member operable to an attachment blocking position that blocks attachment of the claw shaft portion to the drive shaft and an attachment allowing position that allows attachment of the claw shaft portion to the drive shaft;
an operating portion that is provided on the claw shaft portion and that, when the claw shaft portion is attached to the drive shaft in the inverted position, comes into contact with the claw shaft blocking member, thereby operating the claw shaft blocking member to the attachment allowable position;
a forward rotation preventing member operable to a forward rotation preventing position that prevents operation of the transmission device to the forward rotation position, and a forward rotation allowing position that allows operation of the transmission device to the forward rotation position and prevents operation to the forward rotation preventing position when the transmission device is operated to the forward rotation position;
a linking member connected across the forward rotation preventing member and the pawl shaft preventing member,
When the claw shaft portion is attached to the drive shaft in the reverse orientation, the claw shaft blocking member is operated to the attachment allowance position by the operating portion, and the forward rotation blocking member is operated to the forward rotation blocking position via the linking member,
When the forward rotation preventing member is operated to the forward rotation allowing position, the claw shaft preventing member is operated to the attachment preventing position via the linking member, and when the transmission device is operated to the forward rotation position, the claw shaft preventing member is held at the attachment preventing position via the forward rotation preventing member and the linking member,
the claw shaft blocking member is the attitude detection unit and the claw shaft restraining unit,
The forward rotation preventing member is the forward rotation detecting section and the forward rotation restraining section of the walking type tiller. The operating part is provided around the entire circumference of the claw shaft portion, and contacts the claw shaft blocking member regardless of the phase in the rotational direction of the drive shaft when the claw shaft portion is attached in the reverse position. The tillage implement has a first claw shaft portion attached to one of the right and left portions of the drive shaft and a second claw shaft portion attached to the other of the right and left portions of the drive shaft,
a right claw shaft blocking member operable to an attachment blocking position that blocks attachment of the claw shaft portion to the right portion of the drive shaft and an attachment allowing position that allows attachment of the claw shaft portion to the right portion of the drive shaft;
a left claw shaft blocking member operable to an attachment blocking position that blocks attachment of the claw shaft portion to the left portion of the drive shaft and an attachment allowing position that allows attachment of the claw shaft portion to the left portion of the drive shaft,
A walk-behind cultivator as described in any one of claims 1 to 6, wherein the forward rotation preventing member is operated to the forward rotation preventing position via the connecting member by at least one of the right claw shaft preventing member being operated to the installation allowable position and the left claw shaft preventing member being operated to the installation allowable position. A walk-behind cultivator as described in claim 8, wherein when the transmission device is operated to the forward rotation position, the right claw shaft blocking member and the left claw shaft blocking member are held in the mounting blocking position via the forward rotation preventing member and the connecting member. The tillage implement has a first claw shaft portion attached to one of the right and left portions of the drive shaft and a second claw shaft portion attached to the other of the right and left portions of the drive shaft,
The first claw shaft portion and the second claw shaft portion can be attached to the drive shaft in an inward position in which the tillage tines face the left-right central portion of the tillage device when viewed from behind, and in an outward position in which the tillage tines face outward from the left-right central portion of the tillage device when viewed from behind,
When the claw shaft portion is attached to the drive shaft in the reverse orientation and the inward orientation, the operating portion comes into contact with the claw shaft blocking member, thereby operating the claw shaft blocking member to the attachment allowable position, and when the claw shaft portion is attached to the drive shaft in the reverse orientation and the outward orientation, the operating portion comes into contact with the claw shaft blocking member, thereby operating the claw shaft blocking member to the attachment allowable position,
an avoidance portion is provided on the operating portion, and when the claw shaft portion is attached to the drive shaft in the forward orientation or the inward orientation, the avoidance portion prevents the operating portion from hitting the claw shaft blocking member, and when the claw shaft portion is attached to the drive shaft in the forward orientation or the outward orientation, the avoidance portion prevents the operating portion from hitting the claw shaft blocking member;
When the claw shaft portion is attached to the drive shaft in the reverse orientation and the inward orientation, the claw shaft blocking member is operated to the attachment allowance position by the operating portion, and the forward rotation blocking member is operated to the forward rotation blocking position via the linking member,
A walk-behind cultivator described in any one of claims 1 to 6, wherein when the claw shaft portion is attached to the drive shaft in the reverse position and the outward position, the claw shaft blocking member is operated to the attachment allowance position by the operating unit, and the forward rotation blocking member is operated to the forward rotation blocking position via the connecting member . The operating portion is provided around the entire circumference of the claw shaft portion, and abuts against the claw shaft blocking member regardless of the phase in the rotation direction of the drive shaft at which the claw shaft portion is attached in the reverse orientation or the inward orientation, and regardless of the phase in the rotation direction of the drive shaft at which the claw shaft portion is attached in the reverse orientation or the outward orientation,
The avoidance portion is provided around the entire circumferential circumference of the operating portion, and prevents the operating portion from hitting the claw shaft blocking member regardless of the phase in the rotational direction of the drive shaft at which the claw shaft portion is attached to the drive shaft in the forward position or the inward position, or regardless of the phase in the rotational direction of the drive shaft at which the claw shaft portion is attached to the drive shaft in the forward position or the outward position.