JP2024094130A - Walk-behind cultivator - Google Patents

Abstract

[Problem] To prevent the occurrence of dashing in a walk-behind cultivator equipped with a tilling device in which a claw shaft portion is configured so as to be changeable between a forward position and a reverse position.
[Solution] A transmission device is provided that can be operated to a forward rotation position where the power for rotating the drive shaft 11 in the forward rotation direction S12 is transmitted to the drive shaft 11, and to a stop position where the power to the drive shaft 11 is cut off. The claw shaft portion can be attached to the drive shaft 11 in a forward orientation and a reverse orientation. The transmission device is provided with inhibition portions 45, 46, 50 that prevent the occurrence of a state in which the claw shaft portion is attached to the drive shaft 11 in the reverse orientation and the transmission device is operated to the forward rotation position.
[Selected figure] Figure 5

Description

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

As disclosed in Patent Document 1, the tilling device has a tine shaft portion attached to the drive shaft of the machine body, and tilling tines attached to the tine shaft portion. In the tilling device, the tine shaft portion (drive shaft) is rotated in a forward direction such that the tines pass through the tine shaft portion from above to the front, penetrate into the ground, and push soil on the ground backward (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) in which the more radially outward the tine shaft is from the tilling tine, the further upstream in the forward rotation direction it is. As a result, in a walk-behind tilling machine, 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, which is the normal tilling state.

In some tillage devices, the claw shaft is configured to be attached to the drive shaft in a reverse position, which is located downstream in the forward rotation direction, as the radially outward portion of the tillage tines from the claw shaft, as opposed to the forward position described above, and the claw shaft is configured to be changeable between the forward position and the reverse position.

JP 2016-10384 A

In a tilling implement, 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 tilling tine penetrates into the ground before the middle part of the tilling tine, and a large reaction force from the ground is generated that strongly pushes the tilling implement forward.
As a result, the force pushing the tilling implement forward may cause the walk-behind cultivator to be pushed forward (hereinafter referred to as "dashing").

The present invention aims to configure a walk-behind cultivator equipped with a tilling device in which the claw shaft can be changed between a forward and reverse orientation, so that the occurrence of dashing can be avoided.

The walk-behind cultivator of the present invention comprises a body supported by a traveling device, a drive shaft supported on the rear of the body in the left-right direction, a claw shaft portion attached to the drive shaft, and tilling tines attached to the claw shaft portion, and includes a tilling device driven by the drive shaft, a forward rotation position for transmitting power to the drive shaft in a forward rotation direction in which the tilling tines pass from the top to the front of the claw shaft portion and penetrate into the ground, pushing soil on the ground backward, and a power supply to the drive shaft. The transmission device can be operated to a stop position that blocks the transmission, and the tine shaft portion can be attached to the drive shaft in a forward position that is located upstream in the forward rotation direction as the portion of the tine is radially outward from the tine shaft portion of the tilling tine, and in a reverse position that is located downstream in the forward rotation direction as the portion of the tine is radially outward from the tine shaft portion of the tilling tine, and is equipped with a restraining portion that prevents the tine shaft portion from being attached to the drive shaft in the reverse position 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 position and the claw shaft (drive shaft) from being rotated in the forward direction, making it easier to avoid dashing in a walk-behind cultivator equipped with a tilling device in which the claw shaft can be changed between a forward position and a reverse position.

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

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

In the present invention, the tilling device has a first claw shaft portion attached to one of the right and left parts of the drive shaft, and a second claw shaft portion attached to the other of the right and left parts of the drive shaft, and is provided with a right attitude detection portion that detects that the claw shaft portion is attached to the right part of the drive shaft in the reverse attitude, and a left attitude detection portion that detects that the claw shaft portion is attached to the left part of the drive shaft in the reverse attitude, and the forward rotation restraint portion preferably prevents the transmission device from being operated to the forward rotation position when the right attitude detection portion detects that the claw shaft portion is attached to the right part of the drive shaft in the reverse attitude, and when the left attitude detection portion detects that the claw shaft portion is attached to the left part of the drive shaft in the reverse attitude.

Some tilling implements have a first tine shaft portion attached to one of the right and left portions of a 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 a reverse attitude, the forward rotation restraint unit functions, which is advantageous in terms of avoiding dashing of the walking type 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 tilling claw faces toward the left-right center of the tilling device when viewed from behind, and in an outward position where the tilling claw faces outward from the left-right center of the tilling device when viewed from behind, and it is preferable that the position detection unit detects that the claw shaft portion is attached to the drive shaft in the inverse position and the inward position, and detects that the claw shaft portion is attached to the drive shaft in the inverse 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 portion of the drive shaft and the second claw shaft portion can be attached to the left portion of the drive shaft, or conversely, the first claw shaft portion can be attached to the left portion of the drive shaft and the second claw shaft portion can be attached to the right portion of the drive shaft.
This allows the claw shaft portion to be attached to the drive shaft in an inward orientation, and allows 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 a reverse or inward position, or whether the claw shaft section is attached to the drive shaft in a reverse 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 has a normal rotation detection unit that detects that the transmission device has been operated to the normal rotation position, and a claw shaft restraining unit that prevents the claw shaft unit from being attached to the drive shaft in the reverse orientation when the normal rotation detection unit detects that the transmission device has been operated to the normal rotation position.

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

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

Some tilling implements have a first tine shaft portion attached to one of the right and left portions of a 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 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 shaft portion to the right side of the drive shaft in a reverse orientation, the claw shaft restraining unit prevents the claw shaft portion from being attached to the right side of the drive shaft in a reverse orientation.Similarly, even if an operator attempts to attach the claw shaft portion to the left side of the drive shaft in a reverse orientation, the claw shaft restraining unit prevents the claw shaft portion from being attached to the left side of the drive shaft in a reverse orientation.

This allows the worker to recognize at an early stage when attempting to attach the claw shaft portion to either the right or left part of the drive shaft in a reverse orientation that the claw shaft portion is being attached to the drive shaft in a reverse orientation.

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

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

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

As described above, according to the present invention, the claw shaft is attached to the drive shaft in a reverse orientation, and it is possible to avoid a state in which the claw shaft (drive shaft) is driven to rotate in the forward direction, which is advantageous in terms of preventing dashing in walk-behind cultivators.

In the present invention, a claw shaft blocking member operable to an attachment blocking position that blocks the attachment of the claw shaft portion to the drive shaft and an attachment allowable position that allows the 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, can operate the claw shaft blocking member to the attachment allowable position by contacting the claw shaft blocking member; a forward rotation blocking member operable to a forward rotation allowable position that blocks the operation of the transmission device to the forward rotation position and allows the 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 forward rotation blocking member connected across the forward rotation blocking member and the claw shaft blocking 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 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. 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 claw shaft blocking member are provided, and the forward rotation preventing member and the claw shaft blocking member are connected via a linking member. When the claw shaft blocking member is operated to the attachment allowable 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 allowable position, the claw shaft blocking member is operated to the attachment 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 with the transmission device not being operated to the normal 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 permitting position. When the pawl shaft blocking member is operated to the attachment permitting position, this operation is transmitted to the normal rotation blocking member via the linking member, and the normal rotation blocking member is operated to the forward blocking 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 the reverse position (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, and therefore the claw shaft blocking member is held in the attachment blocking position via the forward rotation blocking member and the linking 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 comes into contact with the claw shaft blocking member held in the attachment blocking position, and the operator is therefore unable 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 claw shaft blocking member are provided, the forward rotation preventing member and the claw shaft blocking member are mechanically connected via a linking member, which is a simple configuration, and it is possible to avoid a state in which the claw shaft portion is attached to the drive shaft in a reverse orientation and the claw shaft portion (drive shaft) is driven to rotate in the forward direction, thereby simplifying the structure.

According to the present invention, the claw shaft blocking member has the function of a position detection section that detects when the claw shaft is attached to the drive shaft in an inverted position, and the function of a claw shaft restraining section 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 has the function of a forward rotation detection section that detects when the transmission device is operated to the forward rotation position, and the function of a forward rotation restraint section that prevents the transmission device from being operated to the forward rotation position, so that the structure can be simplified by combining the functions.

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

In a tilling machine, 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 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 an inverted position.
As a result, regardless of whether the claw shaft portion is attached (or is attempted to be attached) in an inverted position and in any phase of the rotational direction of the drive shaft, the claw shaft blocking member can function as a position detection portion and as a claw shaft restraining portion, which is advantageous in terms of avoiding dashing in walk-behind cultivators.

In the present invention, the tilling device has a first claw shaft portion attached to one of the right and left parts of the drive shaft, and a second claw shaft portion attached to the other of the right and left parts of the drive shaft, and is provided with a right claw shaft blocking member operable to the mounting blocking position that blocks the mounting of the claw shaft portion to the right part of the drive shaft and the mounting allowable position that allows the mounting of the claw shaft portion to the right part of the drive shaft, and a left claw shaft blocking member operable to the mounting blocking position that blocks the mounting of the claw shaft portion to the left part of the drive shaft and the mounting allowable position that allows the mounting of the claw shaft portion to the left part of the drive shaft, and it is preferable that the forward rotation blocking member is operated to the forward rotation blocking position via the linking member by at least one of the following: the right claw shaft blocking member is operated to the mounting allowable position, and the left claw shaft blocking member is operated to the mounting allowable position.

Some tilling implements have a first tine shaft portion attached to one of the right and left portions of a 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 section, which is advantageous in terms of avoiding dashing of the walk-behind type cultivator.

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 blocking member and the left claw shaft blocking member are held in the mounting blocking position via the forward rotation preventing member and the linking member.
Even if an operator attempts to attach the claw shaft portion to the right side of the drive shaft in the reverse position, the right claw shaft blocking member prevents the claw shaft portion 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 shaft portion to the left side of the drive shaft in the reverse position, the left claw shaft blocking member prevents the claw shaft portion from being attached to the left side of the drive shaft in the reverse position.
This enables the worker to recognize at an early stage when he or she is about to attach the claw shaft portion in a reverse position to one of the right and left parts of the drive shaft.

In the present invention, the tilling device has a first claw shaft portion attached to one of the right and left parts of the drive shaft, and a second claw shaft portion attached to the other of the right and left parts of the drive shaft, and 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 tilling claw faces the left-right central part of the tilling device in a rear view, and an outward position in which the tilling claw faces outward from the left-right central part of the tilling device in a rear view, and the operating unit can operate the claw shaft blocking member to the mounting allowable position by abutting on the claw shaft blocking member when the claw shaft portion is attached to the drive shaft in the reverse position and the inward position, and can operate the claw shaft blocking member to the mounting allowable position by abutting on the claw shaft blocking member when the claw shaft portion is attached to the drive shaft in the reverse position and the outward position, and The claw shaft portion is provided on the drive shaft, and when the claw shaft portion is attached to the drive shaft in the forward position and the inward position, the operating portion is prevented from hitting the claw shaft blocking member, and when the claw shaft portion is attached to the drive shaft in the forward position and the outward position, the avoidance portion is provided to prevent 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 position and the outward position, the operating portion operates the claw shaft blocking member to the attachment allowable position, and the forward rotation blocking member is operated to the forward rotation blocking position via the linking member, and when the claw shaft portion is attached to the drive shaft in the reverse position and the outward position, the operating portion operates the claw shaft blocking member to the attachment allowable position, and the forward rotation blocking member is operated to the forward rotation blocking position via the linking member.

According to the present invention, when the claw shaft portion is attached to the drive shaft in a reverse or inward orientation (when the claw shaft portion is attached to the drive shaft in a reverse or outward orientation) while the transmission device is not operated to the forward rotation position, the claw shaft blocking member is operated to the attachment allowable position and the forward rotation blocking member is operated to the forward rotation blocking position, so that the operator cannot 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 and the forward rotation prevention member is held in the forward rotation allowing position, even if an operator attempts to attach the claw shaft portion to the drive shaft in the reverse and inward positions (reverse and outward positions), the operator cannot attach the claw shaft portion to the drive shaft in the reverse and inward positions (reverse and outward positions).

This prevents the claw shaft from being attached to the drive shaft in a reverse and inward position (reverse and outward position) and the claw shaft (drive shaft) from being rotated in the forward direction, which is advantageous in preventing dashing of walk-behind cultivators.

When a cultivating device is provided with a first claw shaft portion and a second claw shaft portion, in addition to the claw shaft portion being capable of being attached to the drive shaft in a reverse position and an inward position (reverse position and outward position), the claw shaft portion 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 orientation and an inward orientation (forward orientation and outward orientation), the avoidance portion prevents the operating portion from coming into contact with the claw shaft blocking member, and the claw shaft blocking member is not operated to the attachment allowing position, so the forward rotation blocking member is not operated to the forward rotation blocking position.
This means that with the claw shaft portion 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 that there is no reduction in the operability 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 and inward positions (forward and outward positions), so that there is no reduction in the operability of the walk-behind cultivator.

In the present invention, the operating part is preferably provided around the entire circumference of the claw shaft part, and abuts against the claw shaft blocking member no matter what phase in the rotation direction of the drive shaft the claw shaft part is attached to in the reverse position or the inward position, or what phase in the rotation direction of the drive shaft the claw shaft part is attached to in the reverse position or the outward position, and the avoidance part is preferably provided around the entire circumference of the operating part, and abuts against the claw shaft blocking member no matter what phase in the rotation direction of the drive shaft the claw shaft part is attached to in the forward position or the inward position, or what phase in the rotation direction of the drive shaft the claw shaft part is attached to in the forward position or the outward position.

In a tilling machine, 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 regardless of the phase in the rotational direction of the drive shaft in which the claw shaft portion is attached (or is about to be attached) in the reverse position and in the inward position (reverse position and outward position), the operating portion comes into contact with the claw shaft blocking member.
As a result, regardless of whether the claw shaft portion is attached (or is to be attached) in the reverse or inward position (reverse or outward position) and in any phase of the rotational direction of the drive shaft, the claw shaft blocking member can function as a position detection portion and as a claw shaft restraining portion, which is advantageous in terms of avoiding dashing in walk-behind cultivators.

According to the present invention, the avoidance portion is provided around the entire circumferential direction 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 attempted to be attached) in a reverse or inward position (reverse or outward position) or in any phase of 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 and inward positions (forward and outward positions), so that there is no reduction in the operability of the walk-behind cultivator.

FIG. FIG. 2 is a schematic diagram showing the transmission system inside the transmission case. FIG. FIG. 4 is a rear view of the tine shaft portion and the tillage tines in the tillage implement. FIG. 4 is a left side view showing the inside of the transmission case. FIG. FIG. FIG. 4 is a rear view of the vicinity of the claw shaft blocking member and the drive shaft. FIG. 4 is a plan view of the vicinity of the claw shaft blocking member and the drive shaft. 13 is a schematic diagram showing a state in which the claw 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. 11 is a schematic diagram showing a state in which the claw shaft portion is attached to the drive shaft in a reverse position and an outward position, and the shift lever cannot be operated to the normal rotation position. FIG. 13 is a schematic diagram showing a state in which the shift lever is operated to a normal rotation position and the claw shaft portion cannot be attached to the drive shaft in a reverse or inward orientation. FIG. 13 is a schematic diagram showing a state in which the shift lever is operated to a normal rotation position and the claw shaft portion cannot be attached to the drive shaft in a reverse or outward orientation. FIG. 11 is a schematic diagram showing a state in which the claw shaft portion is attached to the drive shaft in a forward position and an inward position, and the shift lever can be operated to a forward rotation position. FIG. 11 is a schematic diagram showing a state in which the claw 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.

A walk-behind cultivator is shown in Figures 1 to 15, 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 cultivator)
1, right and left running wheels 1 (corresponding to running gear) are provided on the lower part of a transmission case 2 (corresponding to a machine body), and the transmission case 2 is supported by the wheels 1. A support frame 3 is connected to the front part of the transmission case 2, and an engine 4 is supported by the support frame 3.

The steering handle 5 is connected to the top of the transmission case 2 and extends diagonally rearward and upward from the transmission case 2, and the speed change lever 6 extends diagonally rearward and upward from the transmission case 2. A rotary type tilling device 7 is provided at the rear of the transmission case 2.

As shown in FIG. 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 changed in speed by the transmission 10 and transmitted to the wheels 1, as described below.

The drive shaft 11 is supported at the rear of the transmission case 2 in the left-right direction. A forward/reverse rotation device 12 (corresponding to a transmission device) is provided inside the transmission case 2, and the power of the input shaft 8 is transmitted to the drive shaft 11 as forward and reverse power from the forward/reverse rotation device 12, as described below, and the drive shaft 11 is rotated, and the tilling device 7 is driven by the drive shaft 11.

As shown in Figure 1, the above configuration provides a machine body (transmission case 2) supported by a running device (wheels 1). A drive shaft 11 is supported in the left-right direction at the rear of the machine body (transmission case 2).

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

Transmission shafts 13, 14, and 15 are supported inside transmission case 2 in parallel with input shaft 8. Shift gear 16 is supported by a spline structure so as to be able to rotate and slide integrally with input shaft 8, and shift gear 17 is supported so as to be able to 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 gear 19 and transmission gear 20 meshing.

The 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 a state in which the gear shift 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 gear shift lever 6 is moved from the neutral position N1 to the first forward gear position F1, the gear shift 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 while the shift gear 16 is held in a position where it engages with the shift gear 17.

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

When the gear shift lever 6 is operated from the intermediate position N3 to the reverse position R1, the gear shift lever 6 operates the shift fork 25, and the shift gear 17 is operated to a position where it engages with the transmission gear 18 while maintaining a state where it is engaged 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, the transmission gear 18, the transmission shaft 14, the transmission gears 19 and 20, the transmission shaft 15, and the 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 so as 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 , 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 where it engages with the transmission gear 27, a position where it engages with the transmission gear 29, and a position where 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 with the shift gear 16 held in a position where it meshes with the transmission gear 18.

When the gear shift lever 6 is operated to the first forward gear position F1 and the 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, the power of the input shaft 8 is not transmitted to the drive shaft 11, and the drive shaft 11 stops.

When the shift lever 6 is moved from the stop position N4 to the forward rotation position S11, the shift fork 34 is operated by the shift lever 6, 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 in the forward rotation state to the drive shaft 11 via the shift gear 33, the transmission gears 29, 30, the transmission gears 27, 28, the working clutch 31, the transmission shaft 13, and the 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 FIG. 1.

When the speed change lever 6 is operated 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 operated to a position where it meshes with the transmission gear 27. In this state, the power of the input shaft 8 is transmitted in a reverse state to the drive shaft 11 via the shift gear 33, the transmission gears 27, 28, the working clutch 31, the transmission shaft 13, and the 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 FIG. 1.

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

The claw shaft portions 35 and 37 are configured in a round pipe shape, with two mounting holes 35a and 35b opening in the radial direction in the claw shaft portion 35, and two mounting holes 37a and 37b opening in the radial direction in the claw shaft portion 37.

A large-diameter, disk-shaped operating part 40 and cover 39 are connected to one end of the claw shaft parts 35, 37, and a small-diameter, disk-shaped operating part 41 and cover 39 are connected to the other end of the claw shaft parts 35, 37.

At the claw shaft portion 35, the tilling claw 36 is attached to the claw shaft portion 35 in a position facing the operating unit 40. At the claw shaft portion 37, the tilling claw 38 is attached to the claw shaft portion 37 in a position facing the operating unit 41.

In the drive shaft 11, mounting holes 11a, 11b are opened along the radial direction on the right and left parts of the drive shaft 11. The claw shaft parts 35, 37 are inserted into the right and left parts of the drive shaft 11, and the connecting pin 42 is inserted through the mounting holes 35a, 35b, 37a, 37b of the claw shaft parts 35, 37 and the mounting holes 11a, 11b of the drive shaft 11, thereby connecting the claw shaft parts 35, 37 to the drive shaft 11.

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

As shown in Figures 1 and 2, the tilling tines 36, 38 pass from the top to the front of the tine shafts 35, 37, penetrate into the ground, and push the soil on the ground backward. The drive shaft 11 is rotated in a forward direction S12, and the power is transmitted to the forward rotation position S11, and the drive shaft 11 is driven to a stop position N4, which can be operated to cut off the power to the drive shaft 11.

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

As shown in Figures 4 and 10, the claw shaft portion 35 is inserted into the right part of the drive shaft 11 from the operating part 40 side, the claw shaft portion 37 is inserted into the left part of the drive shaft 11 from the operating part 41 side, and the connecting pin 42 is 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 and inward orientation.
The reverse orientation is an orientation in which the more radially outward the portions of the tines 36, 38 are from the tine shaft portions 35, 37, the more downstream in the forward rotation direction S12 they are.
The inward facing position is a position in which the tilling tines 36, 38 face toward the left-right center of the tilling 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 part of the drive shaft 11 from the operating part 41 side, the claw shaft portion 37 is inserted into the right part of the drive shaft 11 from the operating part 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.

The state shown in FIG. 11 is a state in which the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted and outward orientation.
The outward position is a position in which the tilling tines 36, 38 face outward relative to the left-right center of the tilling 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 part of the drive shaft 11 from the operating part 40 side, the claw shaft portion 37 is inserted into the right part of the drive shaft 11 from the operating part 41 side, and the connecting pin 42 is 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, 37 are attached to the drive shaft 11 in a forward orientation and an inward orientation.
The forward orientation is a position in which the portions of the tilling 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.
The state shown in FIG. 15 is a state in which the claw shaft portions 35, 37 are attached to the drive shaft 11 in a forward orientation and an outward orientation.

(Installation on the drive shaft of the tilling equipment) - 2
With the above configuration, as shown in Figures 10, 11, 14 and 15, in the tillage device 7, the tine shaft portions 35, 37 can be attached to the drive shaft 11 in a forward position in which the portion of the tines 36, 38 that is radially outward from the tine shaft portions 35, 37 is positioned upstream of the forward rotation direction S12, and in a reverse position in which the portion of the tines 36, 38 that is radially outward from the tine shaft portions 35, 37 is positioned 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 an inward position where the tilling tines 36, 38 face toward the left-right center of the tilling device 7 when viewed from behind, and in an outward position where the tilling tines 36, 38 face outward from the left-right center of the tilling device 7 when viewed from behind.

(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 part, the attitude detection part, and the claw shaft restraining part) is supported on the right part of the rear part 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.

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

The state shown in Figures 8 and 9 is a state in which the right and left claw shaft blocking members 45, 46 are located in the mounting blocking position A11 protruding outward from the transmission case 2, and the right and left claw shaft blocking members 45, 46 can be moved to the mounting allowable position A12 recessed inside the transmission case 2.

The right and left claw shaft blocking members 45, 46 are connected by operating members 44, 47 and a connection pin 48. As a result, when one of the right and left claw shaft blocking members 45, 46 is operated to the mounting blocking position A11, the other of the right and left claw shaft blocking members 45, 46 is operated to the mounting blocking position A11 via the operating members 44, 47 and the connection 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 operation part of the claw shaft part)
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 and the length L2 from the axis P3 of the drive shaft 11 to the left claw shaft blocking member 46 are longer than the length L2.

As shown in FIG. 4 , the operating portions 40 and 41 are disk-shaped and provided around the entire circumference of the claw shaft portions 35 and 37 .
As shown in FIG. 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.

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

As shown in FIG. 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 circumference of the operating part 41 in the circumferential direction.

When the claw shaft portions 35, 37 are inserted into the right part of the drive shaft 11 from the operating part 40 side, the outer periphery of the operating part 40 comes into contact with the right claw shaft blocking member 45, and the right claw shaft blocking member 45 is operated from the mounting blocking position A11 to the mounting allowable position A12.

When the claw shaft portions 35, 37 are inserted into the right part of the drive shaft 11 from the operating part 41 side, the outer periphery of the operating part 41 penetrates below the right claw shaft blocking member 45, so that the right claw shaft blocking member 45 cannot be operated to the allowable mounting 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, so the left claw shaft blocking member 46 cannot be operated to the allowable mounting position A12.

When the claw 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 claw shaft blocking member 46, and the left claw shaft blocking member 46 is operated from the mounting blocking position A11 to the mounting allowable position A12.

(Configuration of operation of the gear shift lever to the forward and reverse positions)
As shown in Figures 5, 6 and 7, the shift shaft 49 is provided in the upper part of the 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 gearshift lever 6 is moved from the first forward gear position F1 to the stop position N4 (see FIG. 3), the lower portion of the gearshift 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 FIG. 3), the shift fork 34 is slid to the left in FIG. 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 FIG. 2).

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

(Configuration of forward rotation prevention member)
As shown in Figures 5, 6 and 7, a shank-shaped forward rotation preventing member 50 (corresponding to the restraining portion, forward rotation detection portion and forward rotation restraining portion) is provided along the left-right direction at the upper part of the front portion of the transmission case 2, above the engaging portion 34a of the shift fork 34, and is supported rotatably around an axis P2 that extends along 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 is a state in which the forward rotation preventing member 50 is operated to a forward rotation allowing 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 reverse position G11, the forward rotation blocking member 50 can be rotated slightly clockwise in FIG. 6 to operate the forward rotation blocking member 50 to a 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 allowing 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 engagement portion 34a of the shift fork 34 enters below the arm 50a of the forward rotation preventing member 50 in the forward rotation allowing position B12.

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

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

As a result, the forward rotation prevention member 50 cannot be moved from the forward rotation permitted position B12 to the forward rotation prevention 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 claw 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 members 47 of the claw shaft preventing members 45 , 46 .

The state shown in Figures 6 to 9 is a state in which the forward rotation prevention member 50 is operated by the spring 51 to the forward rotation permitted position B12, the forward rotation prevention member 50 pulls the linking member 52 forward (towards the forward rotation prevention member 50), and the claw shaft prevention members 45, 46 are operated to the mounting prevention 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 mounting blocking position A11 to the mounting permitted 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 mounting blocking position A11 to the mounting allowable position A12, the linking member 52 is pulled backward (towards 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 under 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 blocking position B11 (the forward rotation blocking member 50 is held in the forward rotation permitted position B12).

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

When the forward rotation preventing member 50 is held in the forward rotation allowing position B12, the claw 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 claw shaft preventing member)-2
With the above-described 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 a restraining portion (claw shaft blocking members 45, 46 and forward rotation blocking member 50) is provided to prevent the occurrence of a state in which the transmission device (forward/reverse rotation device 12) is operated to the forward rotation position S11.

The restraining section (claw shaft blocking members 45, 46 and forward rotation blocking member 50) has a posture detection section (claw shaft blocking members 45, 46) that detects that the claw shafts 35, 37 are attached to the drive shaft 11 in a reverse posture, and a forward rotation restraining section (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 posture detection section (claw shaft blocking members 45, 46) detects that the claw shafts 35, 37 are attached to the drive shaft 11 in a reverse posture.

It is provided with a right attitude detection unit (right claw shaft blocking member 45) that detects when the claw shaft parts 35, 37 are attached to the right part of the drive shaft 11 in an inverted attitude, and a left attitude detection unit (left claw shaft blocking member 46) that detects when the claw shaft parts 35, 37 are attached to the left part of the drive shaft 11 in an inverted attitude.

The restraining section (claw shaft blocking members 45, 46 and forward rotation blocking member 50) has a forward rotation detection section (forward rotation blocking member 50) that detects that the transmission device (forward/reverse rotation device 12) has been operated to the forward rotation position S11, and a claw shaft restraining section (claw shaft blocking members 45, 46) that prevents the claw shaft sections 35, 37 from being attached to the drive shaft 11 in a reverse position when the forward rotation detection section (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 restraining unit (claw shaft blocking member 45, 46) prevents the claw shaft portions 35, 37 from being attached to the right side of the drive shaft 11 in the reverse position, and also prevents the claw shaft portions 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) includes 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. It has a forward rotation inhibition section (forward rotation prevention member 50) that prevents the transmission device (forward/reverse rotation device 12) from being operated to the forward rotation position S11 when it is detected that the transmission device (forward/reverse rotation device 12) has been operated to the forward rotation position S11, and a claw shaft inhibition section (claw shaft inhibition members 45, 46) that prevents the claw shaft sections 35, 37 from being attached to the drive shaft 11 in a reverse position when the forward rotation detection section (forward rotation prevention member 50) detects that the transmission device (forward/reverse rotation device 12) has been operated 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 prevention member 50 is provided that can be operated to a forward rotation prevention position B11 that prevents the transmission device (forward/reverse rotation device 12) from being operated to the forward rotation position S11, and a forward rotation permission position B12 that allows the transmission device (forward/reverse rotation device 12) to be operated to the forward rotation position S11 and prevents operation to the forward rotation prevention position B11 when the transmission device (forward/reverse rotation device 12) is operated to the forward rotation position S11.

Operating parts 40, 41 are provided on the claw shaft parts 35, 37, and when the claw shaft parts 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 attachment allowable position A12.

A linking member 52 is provided that is connected across the forward rotation preventing member 50 and the claw shaft preventing members 45, 46.
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 allowable 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 blocking members 45, 46 are operated to the mounting blocking 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 blocking members 45, 46 are held in the mounting blocking position A11 via the forward rotation preventing member 50 and the linking member 52.
The claw shaft blocking members 45 and 46 are attitude detection units and claw shaft restraining units. The normal rotation blocking member 50 is a normal rotation detection unit and a normal rotation restraining unit.

(In the tilling device, the state after the claw shaft part is attached to the drive shaft in the reverse position, inward position, 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 and inward orientation, 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 the reverse and inward orientations, 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 against the left claw shaft blocking member 46, which is operated to the allowable mounting position A12, and in conjunction with this, the right claw shaft blocking member 45 is operated to the allowable mounting 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 against the left claw shaft blocking member 46, which is 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 the inverted and outward orientations, 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 against the right claw shaft blocking member 45, which is 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 parts 40, 41 are formed in a disk shape, the operating parts 40, 41 come into contact with the claw shaft blocking members 45, 46 no matter what phase in the rotational direction of the drive shaft 11 the claw shaft parts 35, 37 are attached to the drive shaft 11 in the reverse or inward position, or what phase in the rotational direction of the drive shaft 11 the claw shaft parts 35, 37 are attached to the drive shaft 11 in the reverse or outward position.

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 tilling equipment, the state after the claw shaft part is attached to the drive shaft in the reverse position, inward position, reverse position and outward position)-2
With the above-described configuration, as shown in Figures 4 and 8, the operating portions 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 posture.

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

The operating parts 40, 41 are provided around the entire circumference of the claw shaft parts 35, 37, and come into contact with the claw shaft blocking members 45, 46 no matter what phase in the rotational direction of the drive shaft 11 the claw shaft parts 35, 37 are attached to the drive shaft 11 in the reverse or inward position, or what phase in the rotational direction of the drive shaft 11 the claw shaft parts 35, 37 are attached to the drive shaft 11 in the reverse or outward position.

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

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 allowable 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 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 allowable 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.

The forward rotation restraint section (forward rotation prevention member 50) prevents the transmission device (forward/reverse rotation device 12) from being operated to the forward rotation position S11 when at least one of the following is detected: the right attitude detection section (right claw shaft blocking member 45) detects that the claw shaft sections 35, 37 are attached to the right part of the drive shaft 11 in a reverse orientation, and the left attitude detection section (left claw shaft blocking member 46) detects that the claw shaft sections 35, 37 are attached to the left part 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 claw shaft portions 35, 37 from being attached to the right 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 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 tilling 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 via the forward rotation preventing member 50 and the linking member 52, the claw shaft preventing members 45, 46 are held in the mounting preventing position A11.

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 and inward orientation, 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 hits the right claw shaft blocking member 45, and the claw shaft portion 35 cannot be inserted any further into the right part of the drive shaft 11.

When the claw shaft portions 35, 37 are attached to the drive shaft 11 in an inverted and 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 hits the left claw shaft blocking member 46, and the claw shaft portion 37 cannot be 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 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 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 and inward orientation, when the claw shaft portion 37 is inserted into the right part of the drive shaft 11 from the operating part 40 side, the operating part 40 of the claw shaft portion 37 hits the right claw shaft blocking member 45, and the claw shaft portion 37 cannot be inserted any further into the right part of the drive shaft 11.

As mentioned above, when the operating parts 40, 41 of the claw shaft parts 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 parts 35, 37 shown in FIG. 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 between the mounting holes 35a, 35b, 37a, and 37b of the claw shaft portions 35 and 37 and the mounting holes 11a and 11b of the drive shaft 11, and the claw shaft portions 35 and 37 cannot be connected to the drive shaft 11.

(In a tilling device, the tines are attached to the drive shaft in a forward position, an inward position, 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 operating portion 40 side and the claw shaft portion 37 is inserted into the right part of the drive shaft 11 from the operating portion 41 side, the left claw shaft blocking member 46 enters into 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 shafts 35, 37 shown in FIG. 4 coincide with the positions of the mounting holes 11a, 11b of the drive shaft 11, so that the connecting pin 42 can be inserted across 35a, 37a of the claw shafts 35, 37 and the mounting holes 11a, 11b of the drive shaft 11, and the claw shafts 35, 37 can be connected to the drive shaft 11. This is the state in which the claw shafts 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 part of the drive shaft 11 from the operating part 41 side and the claw shaft portion 37 is inserted into the left part of the drive shaft 11 from the operating part 40 side, the outer periphery of the operating part 41 of the claw shaft portion 35 penetrates downward into the right claw shaft blocking member 45, and the left claw shaft blocking member 46 penetrates into the recess 40a of the operating part 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 that the connecting pin 42 can be inserted across 35b, 37b of the claw shaft portions 35, 37 and the mounting holes 11a, 11b of the drive shaft 11, and the claw shaft portions 35, 37 can be connected 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 allowable position A12 (they are left in the attachment blocking position A11).

As a result, the forward rotation prevention member 50 is not operated to the forward rotation prevention position B11 and remains in the forward rotation permitted position B12, so that the shift lever 6 (shift fork 34) can be operated to the forward rotation position S11.

Conversely, suppose that the shift 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 claw 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 a forward and inward orientation (forward and outward orientation) 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, so that the claw shaft portions 35, 37 are attached to the drive shaft 11 in a forward and inward orientation (forward and outward orientation) regardless of the claw shaft blocking members 45, 46.

The recess 40a of the operating part 40 is ring-shaped and is formed around the entire circumference of the operating part 40. The outer periphery (avoidance part) of the operating part 41 is formed around the entire circumference of the operating part 41.

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

(In a tilling device, the tines are attached to the drive shaft in a forward position, an inward position, a forward position, and an outward position)-2
With the above-described configuration, as shown in Figures 8, 14 and 15, an avoidance portion (recess 40a) is provided on the operating portions 40, 41, which prevents the operating portions 40, 41 from hitting the claw shaft blocking members 45, 46 when the claw shaft portions 35, 37 are attached to the drive shaft 11 in the forward and inward orientations, and which prevents the operating portions 40, 41 from hitting the claw shaft blocking members 45, 46 when the claw shaft portions 35, 37 are attached to the drive shaft 11 in the forward and outward orientations.

The avoidance portion (recess 40a) is provided around the entire circumference of the operating portion 40, 41, and prevents the operating portion 40, 41 from hitting the claw shaft blocking member 45, 46 regardless of the phase in the rotational direction of the drive shaft 11 when the claw shaft portion 35, 37 is attached to the drive shaft 11 in the forward or inward position, or in the phase in the rotational direction of the drive shaft 11 when the claw shaft portion 35, 37 is attached to the drive shaft 11 in the forward or outward position.

(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 a reverse posture, a forward rotation restraining actuator (not shown) (corresponding to the forward rotation restraining portion) can 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 checking section has an attitude detection sensor and a forward rotation checking actuator.

(Second Alternative Embodiment of the Invention)
A forward rotation detection sensor (not shown) (corresponding to a forward rotation detection section) 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, 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, 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 a reverse orientation.
As a result, the restraining section has a forward rotation detection sensor and a claw shaft restraining actuator.

(Third Alternative Embodiment of the Invention)
It may also be possible to provide a posture detection sensor (not shown) (corresponding to the posture detection unit) that electrically detects that the claw shaft portions 35, 37 are attached to the drive shaft 11 in a reverse posture, 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-mentioned configuration, when the attitude detection sensor detects that the claw shafts 35, 37 are attached to the drive shaft 11 in a reverse orientation, a forward rotation restraining actuator (not shown) (corresponding to the forward rotation restraining part) can be provided that prevents the forward/reverse rotation device 12 (transmission device) from being operated to the forward rotation position S11.

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, a claw shaft restraining actuator (not shown) (corresponding to the claw shaft restraining portion) can be provided which prevents the claw shaft portions 35, 37 from being attached to the drive shaft 11 in a reverse position.
As a result, the restraining section has a posture detection sensor, a forward rotation detection sensor, a forward 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 travelling device (not shown) may be provided as the travelling 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 walk-behind cultivators in which a tilling device is provided at the rear of the machine body supported by a traveling device.

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

Claims (13)

A machine body supported by a running gear;
A drive shaft supported along the left-right direction at the rear of the aircraft;
A tilling device having a claw shaft portion attached to the drive shaft and a tilling claw attached to the claw shaft portion and driven by the drive shaft;
A transmission device that can be operated to a forward rotation position in which the drive shaft is rotated in a forward rotation direction in which the tilling tines pass from the top to the front of the tine shaft portion, penetrate into the ground, and push soil on the ground backward, and to a stop position in which the power to the drive shaft is cut off;
The tine shaft portion can be attached to the drive shaft in a forward orientation in which the tine shaft portion is located on the upstream side of the forward rotation direction as the tine shaft portion is radially outward from the tine shaft portion, and in a reverse orientation in which the tine shaft portion is located on the downstream side of the forward rotation direction as the tine shaft portion is radially outward from the tine shaft portion.
A walk-behind cultivator in which the claw shaft portion is attached to the drive shaft in the reverse orientation and which is provided with a restraining portion that prevents the occurrence of a state in which the transmission device is operated to the normal rotation position. The restraining unit is
a position detection unit that detects that the claw shaft portion is attached to the drive shaft in the reverse position;
The walk-behind cultivator according to claim 1, further comprising a forward rotation restraint unit which prevents the transmission device from being operated to the forward rotation position when the attitude detection unit detects that the claw shaft portion is attached to the drive shaft in the reverse attitude. The tilling device 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 portion 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 portion of the drive shaft in the reverse attitude,
The walk-behind cultivator of claim 2, 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 tilling claw faces the left and right central portion of the tilling device when viewed from the rear, and in an outward position in which the tilling claw faces outward from the left and right central portion of the tilling device when viewed from the rear,
The walking-type cultivation machine described in claim 3, wherein the posture detection unit detects when the claw shaft portion is attached to the drive shaft in the reverse posture and the inward posture, and detects when the claw shaft portion is attached to the drive shaft in the reverse posture and the outward posture. The restraining unit is
a normal rotation detection unit that detects that the transmission device is operated to the normal rotation position;
The walk-behind cultivator according to claim 1, further comprising a claw shaft restraining portion that prevents the claw shaft portion from being attached to the drive shaft in the reverse position when the forward rotation detection portion detects that the transmission device has been operated to the forward rotation position. The tilling device 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 walk-behind cultivator of claim 5, wherein the claw shaft restraining portion prevents the drive shaft from being attached to the right side in the reverse position of the claw shaft portion when the forward rotation detection portion detects that the transmission device has been operated to the forward rotation position, and prevents the drive shaft from being attached to the left side in the reverse position of the claw shaft portion. The restraining unit is
a position detection unit that detects that the claw shaft portion is attached to the drive shaft in the reverse position;
a normal rotation detection unit that detects that the transmission device is operated to the normal rotation position;
a forward rotation inhibition unit that prevents the transmission device from being operated to the forward rotation position when the attitude detection unit detects that the claw shaft unit is attached to the drive shaft in the reverse attitude;
The walk-behind cultivator according to claim 1, further comprising a claw shaft restraining portion that prevents the claw shaft portion from being attached to the drive shaft in the reverse position when the forward rotation detection portion detects that the transmission device has been operated to the forward rotation position. a claw shaft blocking member operable to a mounting blocking position that blocks mounting of the claw shaft portion to the drive shaft and a mounting allowing position that allows mounting of the claw shaft portion to the drive shaft;
an operation portion that is provided on the claw shaft portion and 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, 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 of the transmission device 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 claw 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 allowable 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 walking type cultivator according to claim 7, wherein the forward rotation prevention member is the forward rotation detection section and also the forward rotation restraining section. The walking type cultivator according to claim 8, wherein the operating part is provided around the entire circumference of the claw shaft part, and contacts the claw shaft blocking member regardless of the phase of rotation of the drive shaft when the claw shaft part is attached in the reverse orientation. The tilling device 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 the mounting blocking position that blocks mounting of the claw shaft portion to the right portion of the drive shaft and to the mounting allowing position that allows mounting of the claw shaft portion to the right portion of the drive shaft;
a left claw shaft blocking member operable to the mounting blocking position that blocks mounting of the claw shaft portion to the left portion of the drive shaft and the mounting allowing position that allows mounting of the claw shaft portion to the left portion of the drive shaft,
A walk-behind cultivator as described in claim 8, wherein the forward rotation preventing member is operated to the forward rotation preventing position via the linking 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. The walk-behind cultivator according to claim 10, 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 blocking member and the linking member. The tilling device 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 tilling claw faces the left and right central portion of the tilling device when viewed from the rear, and in an outward position in which the tilling claw faces outward from the left and right central portion of the tilling device when viewed from the rear,
When the claw shaft portion is attached to the drive shaft in the reverse orientation and the inward orientation, the operating portion can operate the claw shaft blocking member to the attachment allowable position by contacting the claw shaft blocking member, and when the claw shaft portion is attached to the drive shaft in the reverse orientation and the outward orientation, the operating portion can operate the claw shaft blocking member to the attachment allowable position by contacting the claw shaft blocking member,
an avoidance portion is provided on the operating portion, and prevents the operating portion from hitting the claw shaft blocking member when the claw shaft portion is attached to the drive shaft in the forward orientation and the inward orientation, and prevents the operating portion from hitting the claw shaft blocking member when the claw shaft portion is attached to the drive shaft in the forward orientation and the outward orientation,
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 allowable position by the operating portion, and the normal rotation blocking member is operated to the normal rotation blocking position via the linking member,
A walk-behind cultivator as described in claim 8, 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 allowing position by the operating unit, and the forward rotation blocking member is operated to the forward rotation blocking position via the linking 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 rotational direction of the drive shaft in which the claw shaft portion is attached to the drive shaft in the reverse orientation or the inward orientation, and regardless of the phase in the rotational direction of the drive shaft in which the claw shaft portion is attached to the drive shaft in the reverse orientation or the outward orientation,
The walk-behind cultivator of claim 12, wherein 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, and 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.

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