JP2020128203A - Clamping pressure safety mechanism for walking-type work vehicle - Google Patents

Abstract

To make it possible to stop the driving of a vehicle in a case where there is a possibility that clamping pressure is generated even in a case other than a case where a vehicle body is moved horizontally in a front-back direction in a stable manner.SOLUTION: In a clamping pressure safety mechanism 1, in a case where a clutch rod 6 is in a normal connection posture which is a normal posture when connecting a clutch 7, the state of a rotary shaft 10 is maintained in a normal state. On the other hand, in a case where a load causing the clutch rod 6 to move in a prescribed direction including a specified rotational direction and a direction other than the specified rotational direction is applied to the clutch rod 6 to a degree causing deviation from the normal connection posture, the normal state is changed. In response to the change of the normal state, the supply of power to a drive part is stopped. In a case where excessive force is applied in the prescribed direction, the driving of a vehicle is stopped.SELECTED DRAWING: Figure 1

Description

The present invention relates to a pinching safety mechanism for a walk-type work vehicle, and in particular, it is applied to a walk-type work vehicle in which an operator grips and operates a clutch rod together with a handle rod provided on the rear side of a vehicle body. It is suitable.

2. Description of the Related Art Conventionally, there is known a walk-type work vehicle in which a worker holding a handle rod provided at the rear of a vehicle body accompanies a vehicle that automatically travels by obtaining power from a power source provided in the vehicle body. .. This type of walk-type work vehicle is provided with a clutch rod near the handle rod, and an operator operates the clutch rod to turn on/off transmission of power from a power source to traveling wheels. There are many things. For example, a deadman clutch is widely used, which is in a transmission state when an operator holds the clutch rod together with the handle rod and in a disengaged state when the operator releases the clutch rod.

The handle rod has two independent rods on the left and right sides that can be gripped with the palm of the hand (referred to as a 2-grip type), and the horizontal rods are laid horizontally between the left and right vertical rods. There is one that has a loop-shaped handle (called a loop type). The clutch rod to be gripped together with the handle rod is usually configured according to the shape of the two-grip type or loop type handle rod. That is, in the case where the handle rod is a two-grip type, the clutch rod is also configured by either left or right. On the other hand, when the handle rod is a loop type, the clutch rod is formed in the shape of a bar extending horizontally from side to side.

By the way, the deadman clutch described above is a safety mechanism in which transmission from the power source is cut off when the clutch rod held together with the handle rod is released. However, when the walkable work vehicle is moving backward, the worker is caught with the clutch rod between the obstacle behind and the vehicle, and the clutch rod cannot be returned by the sandwiched body from the power source. It may happen that the transmission of is not cut off. Examples of the case where the walk-type work vehicle is moved backward include direction change (turning/turning back at a narrow place), ridge alignment, and removal from/in a garage.

On the other hand, a safety device has been proposed for the purpose of preventing a pinching accident of a worker when moving backward (for example, refer to Patent Document 1). In Patent Document 1, in a work vehicle in which a handle rod is a loop type, a clamping rod that protrudes rearward from a rear end of the handle rod, and a holding unit that holds a deadman clutch in an “on” state are provided. A traveling safety device is described in which the clamping rod is configured to be movable back and forth, and the holding means can be released by moving the clamping rod forward.

JP, 2005-88769, A

According to the stop operation lever structure described in Patent Document 1, when the operator is sandwiched between the obstacle behind the vehicle and the vehicle, the pinching rod that projects rearward from the rear end of the handle rod is operated. Since the person's body pushes forward, it is possible to release the "on" state of the deadman clutch without releasing the clutch rod. However, the holding state of the deadman clutch can be released in this way only when the worker is squeezed by the work vehicle substantially horizontally in the front-rear direction.

That is, the traveling safety device disclosed in Patent Document 1 is a track-type traveling safety device that includes a crawler traveling device in which a crawler belt is wound around a front tension roller, a rear drive sprocket, and a plurality of grounding rollers below the drive roller. It is supposed to be applied to a work vehicle, and is not supposed to be applied to a walk-type work vehicle having only two wheels on the left and right.

On the other hand, in the case of a two-wheeled walking work vehicle, the vehicle body does not always move horizontally and stably in the case of a pinching accident, and the posture of the vehicle body when the vehicle hits an obstacle during reverse travel and The various states can be caused by various causes such as the angular velocity applied to the traveling wheels and the force of the flip-up that the tilling claw receives from the ground. Therefore, in the case of a two-wheeled walk-type work vehicle, it is necessary to be able to stop the movement of the vehicle even if the vehicle body does not move stably in the front-back direction in the case where a pinching pressure may occur. There is. However, even if the traveling safety device described in Patent Document 1 is applied to a two-wheeled walking work vehicle, if the vehicle body does not move horizontally stably in the front-rear direction, it is possible to effectively respond to the occurrence of pinching pressure. Cannot stop the driving of the vehicle.

The present invention has been made to solve such a problem, and in a two-wheeled walk-type work vehicle, clamping pressure can be applied even when the vehicle body is not horizontally horizontally and stably moving. The purpose is to enable the driving of the vehicle to be stopped when there is a possibility of occurrence.

In order to solve the above-mentioned problems, in the present invention, the clutch rod arranged above the handle rod has a prescribed rotation direction approaching the handle rod via the rotation shaft with respect to the handle rod, and a reverse direction thereof. It is rotatably supported. Then, in the present invention, when the clutch rod is in the normal connecting posture which is the normal posture when the clutch is engaged, the state of the rotating shaft is maintained in the normal state, while the deviation from the normal connecting posture is caused. When a load for moving the clutch rod in a predetermined direction including a prescribed rotation direction and a direction other than the prescribed rotation direction is applied to the clutch rod, the normal state is configured to fluctuate. The power supply to the drive unit that drives the pair of wheels is stopped in accordance with the change in the state.

The pinching pressure occurs when the walking work vehicle is moving backward and the operator cannot release the clutch rod and the vehicle continues to move backward. This is because the handle rod is lifted up, and the operator sandwiched between the vehicle body and the obstacle cannot release the clutch rod, or the clutch rod is the handle rod and the worker's body (or obstacle). The cause is that they get pinched. In this case, regardless of the posture of the vehicle body, that is, whether or not the vehicle body moves stably in the front-rear direction, an abnormal load may be applied to the clutch rod by an operator or an obstacle. become. This abnormal load is not only the "load that attempts to excessively move the clutch rod in the specified rotation direction" that is generated due to the clutch rod being pushed hard against the handle rod, but also the clutch rod. In addition, "a load that attempts to excessively move the clutch rod in a direction other than the specified rotation direction" that is generated due to an improper and unbalanced load is included.

In view of this, according to the present invention configured as described above, regardless of the state of the vehicle, "excessive load in the specified rotation direction" and "directions other than the specified rotation direction" are caused by the pinching pressure. If an "excessive load on" occurs, the power supply to the drive unit is stopped. Therefore, even when the vehicle body does not move horizontally stably in the front-rear direction, the power supply may be stopped to stop the driving of the vehicle when the pinching pressure may occur. it can.

It is a figure showing an example of appearance composition of a walk type work vehicle to which a pinching safety mechanism concerning a 1st embodiment was applied. It is the top view which looked at a walk type work vehicle from the upper part. It is the figure which looked at the left side pinching safety mechanism concerning a 1st embodiment from slanting back. It is the figure which looked at the left side pinching safety mechanism concerning a 1st embodiment from the bottom. FIG. 5 is a sectional view taken along line AA of FIG. 4. It is a front view and a side view of a wall member. It is a figure which shows typically the relationship between a handle rod and a clutch rod. It is a perspective view of the left side pinching safety mechanism which concerns on 1st Embodiment. It is a perspective view of the left side pinching safety mechanism which concerns on 1st Embodiment. It is a perspective view of the left side pinching safety mechanism which concerns on 1st Embodiment. It is a perspective view of the left side pinching safety mechanism which concerns on 1st Embodiment. It is the figure which looked at the left side pinching safety mechanism concerning a 1st embodiment from the bottom. It is a perspective view of the left side pinching safety mechanism which concerns on 1st Embodiment. It is a perspective view of a handle rod and a clutch rod concerning a 2nd embodiment. FIG. 15 is a cross-sectional view near the position P1 in FIG. 14. It is sectional drawing of the left side clamping safety mechanism which concerns on 2nd Embodiment. It is a perspective view of the right side pinching safety mechanism which concerns on 2nd Embodiment. It is the figure which looked at the right side pinching safety mechanism concerning a 2nd embodiment from the bottom. It is a BB sectional view of FIG. It is a side view of the right side pinching safety mechanism which concerns on 2nd Embodiment. It is the figure which looked at the cross section of the right side pinching safety mechanism concerning a 2nd embodiment from the front. It is a side view of a right rotating shaft connecting member. It is the figure which looked at the right side pinching safety mechanism concerning a 2nd embodiment from the top. It is a perspective view of the right side pinching safety mechanism which concerns on 2nd Embodiment. It is the figure which looked at the right side pinching safety mechanism concerning a 2nd embodiment from the top. It is a figure which simplifies and shows the structure of 2nd Embodiment. It is a perspective view of a handle rod and a clutch rod concerning a 3rd embodiment. It is a perspective view of the left side pinching safety mechanism which concerns on 3rd Embodiment. It is the figure which looked at the left side pinching safety mechanism concerning a 3rd embodiment from the back. It is a side view of the left side pinching safety mechanism which concerns on 3rd Embodiment. It is a side view of the left side pinching safety mechanism which concerns on 3rd Embodiment. It is a side view of the left side pinching safety mechanism which concerns on 3rd Embodiment. It is a figure which shows the left side rotating shaft support member and the member relevant to this which concern on 3rd Embodiment. It is a side view of the left side pinching safety mechanism which concerns on 3rd Embodiment. It is a side view of the left side pinching safety mechanism which concerns on 3rd Embodiment. It is a perspective view of the left side pinching safety mechanism which concerns on 3rd Embodiment. It is a side view of the left side pinching safety mechanism which concerns on 3rd Embodiment. It is a side view of the right side pinching safety mechanism which concerns on 3rd Embodiment. It is a side view of the right side pinching safety mechanism which concerns on 3rd Embodiment. It is a side view of the right side pinching safety mechanism which concerns on 3rd Embodiment. It is the figure which looked at the right side pinching safety mechanism concerning a 3rd embodiment from the lower part. It is the figure which looked at the right side pinching safety mechanism concerning a 3rd embodiment from the lower part. It is a side view of the right side pinching safety mechanism which concerns on 3rd Embodiment. It is a side view of the right side pinching safety mechanism which concerns on 3rd Embodiment.

<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an external configuration example of a walk-behind work vehicle 2 to which the pinching safety mechanism 1 according to the present embodiment is applied. FIG. 2 is a plan view of the walk-behind work vehicle 2 as viewed from above. However, FIG. 1 and FIG. 2 are simplified representations of the walk-type work vehicle 2, and in particular, the members related to the pinching safety mechanism 1 are greatly simplified in consideration of the details later. ..

As shown in FIG. 1, a walk-behind work vehicle 2 according to this embodiment includes a vehicle body 3, a traveling wheel 4, a handle rod 5, a clutch rod 6, a clutch 7, a rotary tiller 8 (hereinafter simply referred to as a rotary 8). Also, the pinching safety mechanism 1 is provided, power is automatically supplied from a power source (not shown) such as an engine (internal combustion engine) provided in the vehicle body 3, and the vehicle automatically travels, and the rotary 8 provided behind the vehicle body 3 cultivates the work. It is an agricultural vehicle designed to do.

The traveling wheels 4 are a pair of wheels provided one on each side of the vehicle body 3 and are rotated by the power supplied from the power source to the drive unit of the wheels via the clutch 7. The vehicle body 3 is provided with a drive unit (not shown) that drives the traveling wheels 4 by receiving power from a power source. The clutch 7 is connected between the power source and the drive unit of the wheels. The rotary 8 is provided in the lower rear part of the vehicle body 3, and receives power from a power source to rotate the tilling claw 9. The rotary 8 is configured so that an operator can move up and down around the traveling wheels 4 by moving the handle rod 5 up and down. When the work is tilled, the rotary 8 is lowered and the tiller claw 9 is penetrated into the soil. Used in. Note that, basically, for safety, the walkable work vehicle 2 has a structure in which the tilling claw 9 does not operate when moving backward, or a structure that cannot move backward when the tilling claw 9 operates.

The handle rod 5 is provided on the rear side of the vehicle body 3, and an operator grips the handle rod 5 to operate the walk-type work vehicle 2. The clutch rod 6 is arranged above the handle rod 5 so that an operator grips the clutch rod 6 together with the handle rod 5. As will be described later in detail, the clutch rod 6 has a prescribed rotation direction KD1 approaching the handle rod 5 via the rotary shaft 10 and the bearing 11 with respect to the handle rod 5, and a reverse rotation direction opposite to the prescribed rotation direction KD1. It is rotatably supported by KD2 (see FIG. 1 for both). The clutch rod 6 is connected to the clutch 7 via a clutch wire 12, and when an operator grips the clutch rod 6 together with the handle rod 5, the clutch wire 12 is pulled and the clutch 7 is connected to drive from the power source. The power is transmitted to the section. On the other hand, when the worker releases the clutch rod 6, the clutch wire 12 returns to the original state, the clutch 7 is disconnected, and the transmission of power from the power source to the drive unit is cut off. That is, the operator can control the drive/stop of the drive unit by operating the clutch rod 6.

As shown in FIG. 2, the handle rod 5 is provided between the left and right vertical handle rod portions 14L and 14R extending from the vehicle body 3 toward the rear of the vehicle body, and between the left and right vertical handle rod portions 14L and 14R. It is of a loop type having a lateral handle rod portion 15 which is laterally bridged. In the present embodiment, the left and right vertical handle rod portions 14L and 14R are bent inward at predetermined positions, but such a shape is not essential. Further, the clutch rod 6 is rotatably supported by the left and right longitudinal shafts 14L and 14R of the handle rod 5 by the left and right rotary shafts 10 and extends from the rotary shaft 10 toward the rear of the vehicle body. The vertical clutch rods 16L and 16R and the lateral clutch rod 17 that is laterally bridged between the left and right vertical clutch rods 16L and 16R have a loop structure. The lateral clutch rod portion 17 extends along the lateral handle rod portion 15 on the handle upper side of the lateral handle rod portion 15.

The walk-behind work vehicle 2 according to the present embodiment can be moved forward and backward by changing the operation mode. Then, when the worker is using the walk-behind work vehicle 2 by moving backward, the pinching pressure may occur. In the present embodiment, the pinching means that the worker is pinched by the handle bar 5 and an obstacle such as a wall when the walkable work vehicle 2 is moving backward. When pinching force occurs, a serious accident may occur if the walk-behind work vehicle 2 continues to move backward. Then, the pinching safety mechanism 1 according to the present embodiment is a mechanism that stops the state in which the walkable work vehicle 2 tries to move backward when the pinching may occur. When there is a possibility that pinching pressure has occurred, the pinching safety mechanism 1 stops the state in which the walkable work vehicle 2 is trying to move backward, so that a serious accident can be prevented in advance. it can.

As shown in FIG. 2, the pinching safety mechanism 1 includes a left pinching safety mechanism 1L provided on the left vertical handle rod portion 14L side and a right pinching safety mechanism 1L provided on the right vertical handle rod portion 14R side. The pressure safety mechanism 1R is included. In the present embodiment, with respect to the left side clamping safety mechanism 1L and the right side clamping safety mechanism 1R, the right side clamping safety mechanism 1R does not have the clutch wire 12 (including members related to the clutch wire 12). While different, the other parts have the same structure. Hereinafter, the structure and operation of the left side pinching safety mechanism 1L will be described in detail. In the following description, the direction toward the front side of the vehicle body 3 along the left vertical handle bar 14L is referred to as "the front side of the steering wheel", and the direction toward the rear side is referred to as "the rear side of the steering wheel". The direction toward the left side of the front of the steering wheel is called the "left side of the steering wheel" and the direction toward the right side is called the "right side of the steering wheel". Further, a direction toward the upper side so as to be orthogonal to the front side of the handle is referred to as “the upper side of the handle” and a direction toward the lower side is referred to as “the lower side of the handle”.

FIG. 3 is a diagram of the left side clamping safety mechanism 1L as seen obliquely from behind (a diagram of the left side clamping safety mechanism 1L as seen in the direction indicated by the arrow Y1 in FIG. 2). FIG. 4 is a diagram of the left side pinching safety mechanism 1L viewed from the lower side of the handle toward the upper side of the handle. FIG. 5 is a sectional view taken along line AA of FIG. 3 to 5 respectively show states of the left side pinching safety mechanism 1L and related members when the posture of the clutch rod 6 is a normal disengagement posture (described later). However, in FIG. 3, for ease of viewing the drawing, description of a support rod support member 27 and related members described later is omitted. Further, in FIG. 4, for ease of viewing the drawing, a part of a support rod support member 27 described later is omitted.

As shown in FIGS. 3 to 5, a plate-like restriction plate 19 is attached to a predetermined position of the left vertical handle rod portion 14L. In FIGS. 3 to 5, the structure in which the regulation plate 19 is attached to the left vertical handle rod portion 14L is omitted for the sake of easy viewing, but the regulation plate 19 is actually It extends above the handle than that depicted in FIGS. 3 to 5, and is firmly fixed to the left vertical handle rod portion 14L by means such as screwing.

As shown in FIG. 3, the regulation plate 19 has a regulation hole 21 penetrating the regulation plate 19. As shown in FIG. 3, the bottom portion of the restriction hole 21 extends linearly in the “handle front-back” direction. A narrow portion 22 having a substantially constant width and extending in a “handle front-back” direction is formed on the front side of the handle of the restriction hole 21. A wide portion 23 is formed whose width gradually increases toward. As shown in FIGS. 3 to 5, of the surfaces of the restriction plate 19, a surface 19a facing the opposite side of the left vertical handle rod 14L has a plate-like tip end position restriction protruding outward. The plate 24 is provided along the bottom of the regulation hole 21.

The regulation plate 19 supports the bearing 11. That is, in the present embodiment, the bearing 11 is supported by the handle rod 5 via the regulation plate 19 fixed to the handle rod 5. As shown in FIGS. 3 to 5, the bearing 11 includes a rod-shaped insertion portion support rod 20 and an insertion portion 26 provided at the tip of the insertion portion support rod 20. As shown in FIGS. 3 to 5 (in particular, FIGS. 4 and 5), the insertion portion 26 has a columnar portion formed at the base end portion and a hemisphere whose cross-sectional area decreases toward the right side of the handle. And a shaped portion.

The insertion portion support rod 20 of the bearing 11 is supported so as to be movable in the “handle left-right direction” direction with respect to the regulation plate 19. Specifically, as shown in FIG. 5, the support rod support member 27 is firmly attached to the regulation plate 19 by means such as welding or adhesion. The support rod support member 27 connects the pair of rising portions fixed to the regulation plate 19 to the tip portions of the pair of rising portions, and extends in parallel with the surface of the regulation plate 19 in the parallel extending portion 28. It has and. A through hole is formed at an appropriate position of the parallel extending portion 28, and the cylindrical support rod positioning member 29 is fixed to the parallel extending portion 28 by the nut 25 while penetrating the through hole. Has been done. The insertion portion support rod 20 penetrates the internal space of the support rod positioning member 29 fixed to the parallel extending portion 28. With the support rod positioning member 29 restricting the movement of the insertion portion support rod 20 in a direction other than the “handle left-right” direction, the support rod positioning member 29 “handle left-right”. It is supported so that it can move in any direction.

As shown in FIGS. 3 to 5, a coiled spring 30 (corresponding to the “biasing member” in the claims) is wound around the insertion portion support rod 20. That is, the rod-shaped insertion portion support rod 20 is inserted into the space inside the spring 30. The base end of the spring 30 abuts on the surface of the parallel extending portion 28, and the tip of the spring 30 abuts on the bottom surface of the insertion portion 26, so that the bearing 11 moves to the right of the handle (direction toward the rotating shaft 10). Urge towards.

As shown in FIGS. 3 to 5, the left vertical clutch rod portion 16L extends along the left vertical handle rod portion 14L and forms a surface 16a facing the left vertical handle rod portion 14L. The plate-shaped clutch lever portion 32 is formed. On the surface 16a of the clutch lever portion 32, a fulcrum member 31 is attached at a position behind the rotating shaft 10 (described later) in the handle. The fulcrum member 31 is a member provided so as to project from the surface 16a of the clutch lever portion 32 toward the left vertical handle rod portion 14L, and the contact surface 31a facing the left vertical handle rod portion 14L is Has been formed.

A rotary shaft connecting member 33 is provided at an end of the left vertical clutch rod portion 16L. The rotating shaft connecting member 33 is a plate-shaped member having a portion extending in a direction corresponding to the lower side of the handle and a portion extending from the portion toward the front side of the handle at a substantially right angle. .. The rotating shaft 10, which is a rod-shaped shaft member, is attached to the tip of the rotating shaft connecting member 33, and the rotating shaft connecting member 33 is supported by the rotating shaft 10. In detail, a through hole through which the rotary shaft 10 penetrates is formed at the tip of the rotary shaft connecting member 33, and the through hole extends perpendicularly to the surface of the rotary shaft connecting member 33. The rotary shaft 10 penetrates through, and thereby the rotary shaft 10 supports the rotary shaft connecting member 33. The rotary shaft connecting member 33 is supported by the rotary shaft 10 in a rotatable state with respect to the rotary shaft 10.

The rotary shaft 10 extends to the left of the handle beyond the restriction hole 21 of the restriction plate 19. A tip end portion 34 of the rotary shaft 10 is provided at the tip end portion of the rotary shaft 10 and beyond the restriction hole 21 toward the left side of the handle. The rotary shaft tip portion 34 has a thick rotary shaft base member 35, and the rotary shaft base member 35 is formed with a hole 36 recessed toward the right side of the handle (see FIG. A), FIG. 8, FIG. 9, FIG. 10, and FIG. 13). A cutout portion is formed at an end of the rotary shaft member 35 on the lower side of the handle, and the cutout portion forms a linear cut surface 35a. As will be described later, in the normal connection posture and the normal disconnection posture, the rotary shaft base member 35 is placed on the tip end position regulating plate 24 with its cutting surface 35a being in contact with the upper surface of the tip end position regulating plate 24. To be done. Further, a wall member 38 protruding toward the left side of the handle is provided on the surface of the rotary shaft base member 35 on the left side of the handle and outside the outer periphery of the hole 36. The rotary base member 35 and the wall member 38 are firmly fixed to each other. In the present embodiment, the rotary shaft base member 35 and the wall member 38 are separate members, but these members may be integrally formed by the same member.

FIG. 6A is suitable for explaining how the wall member 38 is viewed from the front when the rotary shaft base member 35 is placed on the tip end position regulating plate 24 (=normal insertion state described later). It is a figure which shows typically in an aspect. FIG. 6B is a diagram schematically showing a side view of the wall member 38, corresponding to FIG. 6A. As shown in FIGS. 6A and 6B, the wall member 38 includes a first wall portion 39 having a height of H1 value and a second wall portion 40 having a height of H2 value (<H1 value). Have and. The H2 value is smaller than half the H1 value and is about ¼ of the H1 value. As shown in FIG. 6(A), the first wall portion 39 has a virtual half line extending upward from the handle O from the center point O of the hole portion 36 on the outer periphery of the outer periphery of the hole portion 36. When defined, it is provided across a range in which the virtual half line is rotated about 90° counterclockwise about the point O and a range rotated about 30° clockwise. Further, the second wall portion 40 is a range that is outside the range where the first wall portion 39 is provided in the outer periphery of the outer periphery of the hole portion 36, and forms a virtual half line centering on the point O. It is provided so as to extend from a position rotated about 30° clockwise to a position rotated about 90° clockwise. As shown in FIG. 6A, the wall member 38 is not provided in the approximately half range on the lower side of the handle with the center of the hole 36 as the center.

As shown in FIGS. 4 and 5, the end of the clutch wire 12 is connected via the clutch wire connecting member 42 to the surface of the rotary shaft connecting member 33 opposite to the surface facing the regulating plate 19. Has been done. The clutch wire 12 extends toward the vehicle body 3 along the left vertical handle rod portion 14L and is connected to the clutch 7 inside the vehicle body 3.

With the above configuration, when the operator is not operating the clutch rod 6 (the state where no force is applied to the clutch rod 6), the posture of the clutch rod 6 with respect to the handle rod 5 becomes the normal disengagement posture. The transmission state of the power from the power source to the drive unit is cut off. When the operator holds the clutch rod 6 together with the handle rod 5 from this normal shut-off posture, the posture of the clutch rod 6 with respect to the handle rod 5 becomes a normal connection posture, and the power is transmitted from the power source to the drive unit. Become. Hereinafter, the states of the main parts in the normal blocking posture and the normal connection posture will be described in detail. As described above, the right-side pinching safety mechanism 1R has the same structure as the left-side pinching safety mechanism 1L except for a predetermined portion. In the following description, each member of the right-side pinching safety mechanism 1R will be left side. The same name and the same reference numeral as those of the corresponding members of the pinching safety mechanism 1L are used.

<Normal blocking posture>
First, the normal blocking posture will be described. As described above, FIGS. 3 to 5 show the states of the left side pinching safety mechanism 1L and related members when the posture of the clutch rod 6 is the normal disengagement posture. In this embodiment, the clutch rod 6 is urged by an urging member (not shown) so as to rotate in the reverse rotation direction KD2, and is rotated when no force is applied to the clutch rod 6. A state in which the shaft 10 is floated in the reverse rotation direction KD2 by a certain amount about the shaft 10 (see FIGS. 3 and 5).

As shown in FIG. 3, in the normal blocking posture, at the end of the wide portion 23 of the restriction hole 21 on the rear side of the handle, the rotary shaft base member 35 of the rotary shaft distal end portion 34 has its cutting surface 35a regulated at the distal end position. In a state of being in contact with the upper surface of the plate 24, it is in a state of being placed on the tip position regulating plate 24. As a result, the movement of the rotary shaft distal end portion 34 to the lower side of the handle is restricted. Further, even if the rotary shaft connecting member 33 rotates, the rotary shaft 10 is prevented from rotating relative to the regulation plate 19. Further, in the normal blocking posture, the back surface of the rotary shaft base member 35 is in contact with the surface 19 a of the regulation plate 19. Further, in the normal blocking posture, the insertion portion 26 of the bearing 11 is in a state of being inserted into the hole portion 36 of the rotating shaft 10. At that time, the insertion portion 26 is biased toward the hole portion 36 by the spring 30, and presses the hole portion 36 toward the right side of the handle. As a result, the rotary shaft distal end portion 34 is sandwiched between the regulation plate 19 and the insertion portion 26 of the bearing 11. Further, as shown in FIGS. 3 to 5, the outer periphery of the cylindrical portion of the base end portion of the insertion portion 26 abuts the inner periphery of the first wall portion 39, whereby the first wall portion 39 is provided. The movement of the insertion portion 26 in the fixed direction is restricted. That is, the tension applied to the clutch wire 12 prevents the insertion portion 26 from moving.

In the present embodiment, the hole 36 is dug in a cylindrical shape, and the tip of the insertion portion 26 is inserted into the cylindrical dug. When the insertion portion 26 is fitted in the hole portion 36, the outer periphery of the insertion portion 26 is in contact with the entire outermost edge of the hole portion 36, and the insertion portion 26 causes the spring 30 to move. Under the condition that the insertion portion 26 is urged by, the insertion portion 26 is in a state of being difficult to be removed from the hole portion 36. As a result, the state in which the insertion portion 26 is fitted in the hole portion 36 and the state in which the rotating shaft 10 corresponding to the hole portion 36 is supported by the bearing 11 corresponding to the insertion portion 26 are appropriately maintained. The hole 36 may be dug in a hemispherical shape. In this case, the curvature of the digging of the hole portion 36 is made larger than the curvature of the tip of the insertion portion 26, so that when the insertion portion 26 is fitted into the hole portion 36, the tip portion of the insertion portion 26 is in the hole portion 36. Since the state reaches the innermost portion of, the insertion portion 26 is firmly fitted into the hole portion 36.

With the above configuration, the position and posture of the rotary shaft 10 with respect to the regulation plate 19 are held. As described above, the right-side pinching safety mechanism 1R has the same structure as the left-side pinching safety mechanism 1L, and even in the right-side pinching safety mechanism 1R, the insertion portion 26 is inserted into the hole portion 36 while being biased. It will be in the state of being. As a result, the position and posture of each of the left and right rotary shafts 10 with respect to the regulation plate 19 is maintained, and the left and right rotary shafts 10 stably support (axially support) the clutch rod 6.

In the following description, the state (the state of FIGS. 3 to 5) in which the insertion portion 26 of the bearing 11 is normally inserted in the hole 36 of the rotating shaft 10 is referred to as the “normal insertion state”. The normal insertion state corresponds to the “predetermined state” and the “insertion state” in the claims. Further, the state of the rotary shaft 10 in the normal insertion state is referred to as “normal state”. As will be described later, the normal insertion state is maintained as the state of the bearing 11 and the rotary shaft 10 even in the normal connection posture. In other words, the normal state is maintained as the state of the rotating shaft 10. In this normal insertion state, the rotating shaft 10 is stably supported by the bearing 11, and the clutch rod 6 is rotatable about the rotating shaft 10 between the normal disconnecting posture and the normal connecting posture.

<Normal connection posture>
Next, the normal connection posture will be described. When the operator holds the clutch rod 6 together with the handle rod 5 when the state of the handle rod 5 and the clutch rod 6 is in the normal disconnecting posture, the clutch rod 6 moves in the specified rotation direction KD1 about the rotary shaft 10 as an axis. Rotate. At that time, in each of the left-side pinching safety mechanism 1L and the right-side pinching safety mechanism 1R, the insertion portion 26 of the bearing 11 is attached to the rotary shaft 10 by the functions of the spring 30, the wall member 38, the tip position regulating plate 24, and the like. The state that the hole 36 is normally inserted is maintained.

When the rotation of the clutch rod 6 in the specified rotation direction KD1 progresses, the contact surface 31a of the fulcrum member 31 comes into contact with the handle rod 5 in each of the left side clamping safety mechanism 1L and the right side clamping safety mechanism 1R, and the clutch rod 6 is engaged. Even if the clutch rod 6 is gripped by a normal force intended to connect the clutch 7, the clutch rod 6 will not rotate any more (more difficult to rotate). This state is the normal connection posture. When the posture of the clutch rod 6 is in the normal connection posture, the clutch wire 12 is pulled toward the rear of the handle to connect the clutch 7, and a transmission state in which power is transmitted from the power source to the drive unit is established.

Now, as described above, the pinching pressure may occur when the walkable work vehicle 2 is moving backward. Immediately before the pinching force is generated, the posture of the clutch rod 6 is in the normally connected posture, and the walkable work vehicle 2 is in the reverse drive state. Here, the walk-behind work vehicle 2 according to the present embodiment is a two-wheeled vehicle that travels with a pair of traveling wheels 4, and since the vehicle body 3 is rotatable around the axles of the pair of traveling wheels 4, the vehicle body with respect to the ground The posture of 3 is not stable, and the posture changes variously. Therefore, the posture of the vehicle body 3 when the pinching force is generated is not constant, and the posture of the vehicle body when the worker bumps into an obstacle during the backward movement, the angular velocity applied to the traveling wheels 4, and the bouncing of the tiller claw 9 received from the ground. It changes variously due to various factors such as the force of raising.

If a pedestrian releases his/her hand from the clutch rod 6 when the pinching force occurs, and the posture of the clutch rod 6 becomes the normal disengagement posture in response to this, the clutch 7 will be disengaged and the vehicle will move backward. There is no problem because the state to be stopped is stopped. However, there is a case where the operator cannot release the clutch rod 6 when the pinching force occurs, or even if the operator releases the clutch rod 6, the posture of the clutch rod 6 does not shift to the normal disengagement posture. For example, when the handle rod 5 is lifted up and an operator sandwiched between the vehicle body 3 and an obstacle cannot release the clutch rod 6, the clutch rod 6 may be the handle rod, for example. This is the case where it is sandwiched between 5 and the worker's body (or obstacle).

In such a case, the state in which the walk-type work vehicle 2 tries to move backward continues, and therefore an abnormal load is applied to the clutch rod 6 by the worker or the obstacle regardless of the posture of the vehicle body 3. .. One specific case when an abnormal load is applied to the clutch rod 6 is that an excessive load to rotate the clutch rod 6 in the normal rotation direction KD1 with respect to the clutch rod 6 in the normal connection posture. This is a case to be added (hereinafter, referred to as “case C1”). The excessive load is a load that exceeds the load required to maintain the normal connection posture and deviates from the normal connection posture. This may occur, for example, when the state in which the vehicle tries to move backward while the clutch rod 6 is sandwiched between the handle rod 5 and the operator (or obstacle) continues regardless of the posture of the vehicle body 3. ..

Further, as another specific case, an excessive load for moving the clutch rod 6 relatively to the front of the handle relative to the handle rod 5 is applied to the clutch rod 6 in the normal connection posture (hereinafter, referred to as “ Case C2”). This is because, for example, a part of a pedestrian (or an obstacle) comes into contact with the clutch rod 6 and pushes the clutch rod 6 back against the clutch rod 6 against the force of going backward of the walkable work vehicle 2. It can occur when a load is applied. FIG. 7A is a diagram schematically showing the handle rod 5 and the clutch rod 6. The state in which the clutch rod 6 moves relatively to the front of the handle relative to the handle rod 5 includes the case where the clutch rod 6 entirely moves to the front of the handle as shown by an arrow X1 in FIG. As shown by arrow X2, it includes a case where the steering wheel is tilted to the right with respect to the front of the steering wheel or moves while tilting, and a case where the steering wheel is tilted to the left with respect to the front of the steering wheel or is moved while tilting. ..

Based on the above, in the pinching safety mechanism 1 according to the present embodiment, it is assumed that pinching pressure may have occurred in any of the cases C1 and C2. The transmission of power to the vehicle is stopped, and the state in which the vehicle is going to move backward is stopped. The operation of the pinching safety mechanism 1 will be described below centering on the operation of the left side pinching safety mechanism 1L in each of the cases C1 and C2.

<Case C1>
First, the operation of the pinching safety mechanism 1 (mainly the left pinching safety mechanism 1L) in the case C1 will be described. 8 to 10 are diagrams used for explaining the operation of the left side clamping safety mechanism 1L in the case of the case C1. FIG. 8 is a diagram of the left side pinching safety mechanism 1L viewed from the rear side of the handle toward the front side of the handle and slightly tilted to the right side of the handle. FIGS. 9 and 10 show the left side pinching safety mechanism 1L. It is the figure seen from the substantially same direction as FIG. 8 to 10 show a state of the left side clamping pressure safety mechanism 1L after clamping pressure is generated and an excessive load for rotating the clutch rod 6 in the specified rotation direction KD1 is applied to the clutch rod 6. The time has passed in the order of FIG. 8→FIG. 9→FIG.

As shown in FIGS. 8 and 9, when an excessive load for rotating the clutch rod 6 in the specified rotation direction KD1 is applied to the clutch rod 6 in the normally connected posture, the fulcrum member 31 is moved by the lever principle. As a fulcrum, a portion of the clutch lever portion 32 in front of the fulcrum member 31 of the handle moves upward in the handle. In response to this, the rotary shaft connecting member 33 provided on the front side of the handle with respect to the fulcrum member 31 moves toward the upper side of the handle (see arrow Y2 in FIGS. 8 and 9). As the rotary shaft connecting member 33 moves upward in the handle, the rotary shaft 10 attached to the rotary shaft connecting member 33 also moves upward in the handle.

When the rotary shaft 10 is moved above the handle, first, a load for moving the rotary shaft 10 above the handle acts on the rotary shaft 10 via the rotary shaft connecting member 33. Accordingly, the hole portion 36 of the rotary shaft distal end portion 34 slides on the surface of the hemispherical insertion portion 26 while pushing back the insertion portion 26 of the bearing 11 against the biasing force of the spring 30, and above the handle. Move towards. As described above, since the wall member 38 is not provided in a certain range on the lower side of the handle centering on the center of the hole 36, the insertion portion 26 may pass through the range where the wall member 38 is not provided. Then, the hole 36 is moved. Therefore, the movement of the hole 36 (in other words, the relative movement of the insertion portion 26 with respect to the hole 36) is not hindered by the wall member 38. Further, in the normal insertion state, the rotating shaft 10 in the normal state is located in the wide portion 23 of the restriction hole 21, and when an excessive load is applied to the clutch rod 6, the handle of the rotating shaft 10 is in the normal state. The upward movement is not restricted by the restriction hole 21. In accordance with the movement of the hole 36, the insertion portion 26 is removed from the hole 36, the normal insertion state is released, and the normal state of the rotary shaft 10 changes.

It should be noted that when the handle rod 5 is normally operated, the "insertion" of the insertion portion 26 from the hole 36 does not occur, while the clutch rod 6 is rotated a prescribed number of times with respect to the clutch rod 6 in the normally connected posture. A spring 30 having an appropriate biasing force is employed under a preliminary test or simulation so that “extraction” occurs in the above-described manner when an excessive load for rotating in the moving direction KD1 is applied.

After the insertion portion 26 is removed from the hole portion 36, when the movement of the hole portion 36 toward the upper side of the handle (=the movement of the rotating shaft 10 toward the upper side of the handle) further proceeds, the insertion portion 26 of the bearing 11 is moved to the outer periphery of the hole portion 36. The state where the rotary shaft 10 is in contact with the inner periphery of the restriction hole 21 (the state shown in FIG. 9) is reached after the state where the rotary shaft 10 rides on the edge (the state shown in FIG. 8). In the state of FIG. 9, further movement of the rotary shaft 10 above the handle is restricted. In this state, the insertion portion 26 of the bearing 11 is located at a position deviated from the rotary shaft tip portion 34 of the rotary shaft 10, and the biasing force of the spring 30 hardly acts on the rotary shaft 10, so that the spring 30 is not biased. The “force that tries to hold the rotary shaft 10 (and the rotary shaft connecting member 33 to which the rotary shaft 10 is connected) at the current position” due to the force hardly acts on the rotary shaft 10.

The tension of the clutch wire 12 that tries to move the member toward the front of the handle acts on the rotary shaft connecting member 33. When the state of FIG. 9 is reached, the tension of the clutch wire 12 causes the rotary shaft connecting member 33 to move. The member 33 (and the rotating shaft 10 connected to the rotating shaft connecting member 33) starts moving toward the front of the handle. An arrow Y3 in FIG. 9 is an arrow indicating a route when the rotary shaft 10 moves in the restriction hole 21. As described above, the narrow portion 22 that extends toward the front of the handle with a substantially constant width is formed in the approximately half range on the front side of the handle of the restriction hole 21, and the rotary shaft 10 includes the rotary shaft base member. The back surface of 35 contacts the surface 19a of the regulation plate 19 and moves toward the front of the handle while being guided by the narrow portion 22. When the rotation shaft connecting member 33 moves toward the front of the handle, the rotation shaft 10 comes into contact with the inner circumference of the restriction hole 21 (the state shown in FIG. 10). In the state shown in FIG. 10, further movement of the rotary shaft 10 toward the front of the handle is restricted.

In the state shown in FIG. 10, the end portion of the clutch wire 12 connected to the rotary shaft connecting member 33 via the clutch wire connecting member 42 is moved to the front of the handle relative to the handle rod 5, and is pulled. The clutch wire 12 is returned to the original state and the clutch 7 is disengaged. As a result, the driving of the drive unit is stopped, and the state in which the walkable work vehicle 2 is going to move backward is stopped. As described above, when an excessive load for moving the clutch rod 6 in the specified rotation direction KD1 is applied to the clutch rod 6, the normal insertion state is released and the normal state of the rotating shaft 10 changes. The position of the rotary shaft 10 relative to the bearing 11 changes in response to the cancellation of the normal insertion state (change in the normal state of the rotary shaft 10), the clutch 7 is disengaged with the change of the rotary shaft 10, and the drive unit is driven. Stops.

The time from the timing when the excessive load is applied to the clutch rod 6 to the timing when the state shown in FIG. 10 is reached is very short, and the clutch 7 is immediately disengaged when the excessive load is applied to the clutch rod 6. As a result, the state in which the walkable work vehicle 2 is trying to move backward is stopped. When an excessive load is applied to the clutch rod 6, the normal insertion state of the right side pinching safety mechanism 1R is released, and the normal state of the rotary shaft 10 changes, resulting in the state shown in FIG.

<Case C2>
Next, the operation of the pinching safety mechanism 1 (mainly the left pinching safety mechanism 1L) in case C2 will be described. As a mode in which the clutch rod 6 moves to the front of the handle in accordance with the occurrence of the clamping pressure, there are not only the mode shown by the arrow X1 in FIG. 7A but also the modes shown by the arrow X2 and the arrow X3. .. In the case of arrow X2, in the case of arrow X1, the load acts to move the rotating shaft 10 forward of the steering wheel (more accurately, in the direction including the component toward the front of the steering wheel) with respect to the rotating shaft 10. The left pinching safety mechanism 1L operates in the same manner as the operation described below. The case of arrow X3 will be described later.

11 to 13 are diagrams used for explaining the operation of the left side clamping safety mechanism 1L in the case of the case C2. FIG. 11 is a view of the left side pinching safety mechanism 1L viewed from the rear side of the handle toward the front side of the handle and slightly tilted to the right side of the handle. FIG. 12 is a view of the left side pinching safety mechanism 1L viewed from the lower side of the handle toward the upper side of the handle. FIG. 13 is a diagram of the left side pinching safety mechanism 1L viewed from the left side of the handle toward the right side of the handle. In addition, FIG. 10 is referred to in the following description of case C2. FIGS. 10 to 13 show states of the left side pinching safety mechanism 1L after the pinching pressure is generated and an excessive load for moving the clutch rod 6 toward the front of the handle is applied to the clutch rod 6. , FIG. 11→FIG. 12→FIG. 13→FIG. 10 in order.

When an excessive load for moving the clutch rod 6 to the front of the handlebar is applied to the clutch rod 6 in the normally connected posture, the rotary shaft connecting member 33 moves to the front of the handlebar as the clutch rod 6 moves to the front of the handlebar. Move towards. As the rotating shaft connecting member 33 moves to the front of the handle, the rotating shaft 10 attached to the rotating shaft connecting member 33 also moves to the front of the handle.

When the rotary shaft 10 moves to the front of the handle, first, a load that moves the rotary shaft 10 to the front of the handle acts on the rotary shaft 10 via the rotary shaft connecting member 33. Accordingly, the hole portion 36 of the rotary shaft tip portion 34 slides on the surface of the hemispherical insertion portion 26 while pushing back the insertion portion 26 of the bearing 11 against the bias of the spring 30, and the front side of the handlebar. Move towards. As described above, in the normal insertion state, since the second wall portion 40 exists on the handle rear side of the insertion portion 26 inserted into the hole portion 36, the hole portion 36 (rotating shaft tip portion 34) is According to the movement toward the front of the handle, the insertion portion 26 will pass through the range where the second wall portion 40 exists. Since the second wall portion 40 has a lower height than the first wall portion 39, the movement of the hole portion 36 (in other words, the relative movement of the insertion portion 26 with respect to the hole portion 36) does not occur. The second wall portion 40 is only limitedly obstructed.

The second wall portion 40 prevents "disengagement" of the insertion portion 26 that may occur when the rotary shaft connecting member 33 is pulled by the clutch wire 12 when the posture of the clutch rod 6 is the normal connection posture. It is provided for the purpose. Therefore, the height of the second wall portion 40 is such that when the posture of the clutch rod 6 is in the normal connection posture, the "dropout" of the insertion portion 26 is appropriately prevented, while the clutch rod 6 is held against the clutch rod 6. It is properly designed under prior tests and simulations so that the "dropout" of the insertion portion 26 is not unnecessarily obstructed when an excessive load is applied to move the handle forward. In accordance with the movement of the hole 36, the insertion portion 26 is removed from the hole 36, the normal insertion state is released, and the normal state of the rotary shaft 10 changes.

After the insertion portion 26 is removed from the hole portion 36, when the movement of the hole portion 36 toward the front of the handle (=the movement of the rotating shaft 10 toward the front of the handle) further proceeds, the insertion portion 26 of the bearing 11 is moved to the outer periphery of the hole 36. After the state of riding on the edge (state of FIG. 12), the rotary shaft distal end portion 34 and the insertion portion 26 are completely displaced in the “handle front-back” direction (state of FIG. 13). In this state, the biasing force of the spring 30 does not act on the rotating shaft 10.

After that, the tension of the clutch wire 12 causes the rotary shaft connecting member 33 (and the rotary shaft 10 connected to the rotary shaft connecting member 33) to further move to the front of the handle, and the rotary shaft 10 comes into contact with the inner periphery of the restriction hole 21. Then, the pulled clutch wire 12 returns to its original state and the clutch 7 is disengaged. As described above, when an excessive load for moving the clutch rod 6 to the front of the handle is applied to the clutch rod 6, the normal insertion state is released, and the rotation with respect to the bearing 11 is released according to the release of the normal insertion state. The position of the shaft 10 is changed (the normal state of the rotary shaft 10 is changed), the clutch 7 is disengaged with the change of the rotary shaft 10, and the driving of the drive unit is stopped.

In the case of the arrow X3 in FIG. 7A, the normal insertion state of the right side pinching safety mechanism 1R is released by the same movement as the left side pinching safety mechanism 1L described above. Thereafter, the load originally applied to the clutch rod 6 due to the pinching pressure and the tension of the clutch wire 12 cause the clutch rod 6 to move forward as a whole, so that the left pinching safety mechanism 1L is normally inserted. The clutch 7 is released and the clutch 7 is disengaged.

<Second Embodiment>
Next, a second embodiment will be described. In the description of the second embodiment, the same elements as those in the first embodiment will be denoted by the same reference numerals as those in the first embodiment, and detailed description thereof will be omitted. Further, the configuration of the walk-type work vehicle 2A to which the pinching safety mechanism 1A according to the second embodiment is applied is the same as that of the first embodiment except for the portion related to the pinching safety mechanism 1A, and thus the walking type work vehicle 2A As for the configuration of the work vehicle 2A, FIGS.

FIG. 14 is a perspective view of the handle rod 5A and the clutch rod 6A in the walkable work vehicle 2A as seen from the upper rear side. In the present embodiment, front handle, rear handle, left handle, right handle, upper handle, and lower handle are defined as in the first embodiment. As shown in FIG. 14, the walkable work vehicle 2A includes a handle rod 5A and a clutch rod 6A arranged above the handle rod 5A, as in the first embodiment. The handle rod 5A includes a left vertical handle rod portion 14AL extending from the vehicle body toward the rear of the vehicle body, a right vertical handle rod portion 14AR, and a lateral handle extending laterally between these handle rod portions. It is a loop-type configuration having a rod portion 15A. Further, the clutch rod 6A is of a loop type having a left vertical clutch rod portion 16AL, a right vertical clutch rod portion 16AR, and a lateral clutch rod portion 17A that is horizontally stretched between these clutch rod portions. It is a composition. As shown in FIG. 14, the pinching safety mechanism 1A includes a left side pinching safety mechanism 1AL provided on the left vertical handle rod portion 14AL side and a right side pinching safety mechanism 1AL provided on the right vertical handle rod portion 14AR side. The pressure safety mechanism 1AR is included.

15 and 16 are diagrams used for explaining the left side clamping safety mechanism 1AL. FIG. 15 is a perspective view of a cross section near the position P1 of FIG. 14 viewed from the rear side of the handle toward the front side of the handle. In addition, in FIG. 15, the left rotary shaft connecting member 50 (described later) is simplified and drawn. FIG. 16 shows the left and right rotation shaft support members 51 (described later) with respect to the member drawn in FIG. It is the figure which saw the cross section cut|disconnected by the vertical surface toward the handle upper side from the handle lower side.

As shown in FIG. 15, at a predetermined position of the left vertical handle rod portion 14AL, a plate-shaped left side rotation shaft supporting portion fixing member 52 has one surface 52a facing the right side of the handle and the other surface thereof. It is attached to the left of the handle. Specifically, as shown in FIG. 15, the upper end portion of the left rotary shaft supporting portion fixing member 52 is provided with bolts and nuts spaced apart in the “handle front-rear” direction so that the left vertical handle rod portion is formed. It is firmly fixed to 14AL.

As shown in FIGS. 15 and 16, on the surface 52a on the right side of the handle of the left rotary shaft supporting portion fixing member 52, the rotary shaft supporting portion positioning member 53 is located below the left vertical handle rod portion 14AL. Is attached, and the left rotation shaft support member 51 is fixed to the surface 52a by the rotation shaft support portion positioning member 53. The rotary shaft support portion positioning member 53 has a pair of flange portions, a pair of rising portions that rise from the pair of flange portions, and a connecting portion 56 that connects the pair of rising portions. Each of them is firmly fixed to the left rotary shaft supporting portion fixing member 52 by a bolt and a nut.

The left rotation shaft support member 51 (corresponding to the “second rotation shaft support member” in the claims) is a columnar member, and is made of an elastic member having elasticity (a rubber member in this embodiment). ing. In particular, the left rotary shaft support member 51 is less likely to be elastically deformed than the rubber member that constitutes the right rotary shaft support member 58 (corresponding to the “first rotary shaft support member” in the claims. Details will be described later). It is composed of a hard rubber member. As shown in FIGS. 15 and 16, the left rotary shaft support member 51 has one end surface in contact with the surface 52a of the left rotary shaft support portion fixing member 52 and the other end surface. The part positioning member 53 is fixed to the left rotary shaft support part fixing member 52 while being in contact with the back surface of the connecting part 56.

As shown in FIG. 16, a first space 57, which is a cylindrical space, is formed on the right side of the handle of the left rotation shaft support member 51 coaxially with the left rotation shaft support member 51. In the left rotation shaft support member 51, on the left side of the handle of the first space 57, there is a cylindrical space coaxial with the first space 57, which communicates with the first space 57 and has a diameter larger than that of the first space 57. The second space 55 having a small size is formed.

As shown in FIG. 16, in the connecting portion 56 of the rotary shaft supporting portion positioning member 53, a connecting portion through hole 59 penetrating the connecting portion 56 is formed at a position corresponding to the first space 57. Further, a left side plate through hole 60 is formed at a position corresponding to the second space 55 in the left side rotation shaft supporting portion fixing member 52. Then, the rod-shaped left side rotation shaft 61 (corresponding to the “second rotation shaft” in the claims) passes through the connection part through hole 59, the first space 57, the second space 55, and the left side plate through hole 60. The connection portion 56, the left side rotation shaft support member 51, and the left side rotation shaft support portion fixing member 52 penetrate in the “handle left side-right side” direction.

As shown in FIG. 16, the diameter of the second space 55 is slightly smaller than the diameter of the left rotation shaft 61, and in the second space 55, the outer periphery of the left rotation shaft 61 has elasticity on the left rotation shaft support member 51. The left side rotation shaft 61 is supported by the left side rotation shaft support member 51 of the rubber member, which is in close contact with the inner periphery of the second space 55 formed in. Further, in the first space 57, the first nut 62 is screwed into the left rotation shaft, and the second nut 64 is screwed into the end portion of the left rotation shaft 61 on the left side of the handle via the collar 63. doing. The left rotation shaft 61 is restricted from moving in the “handle left-right” direction with respect to the left rotation shaft support member 51 by the collar 63 positioned by the first nut 62 and the second nut 64, and is rotated left. It is fixed to the shaft support member 51. When the clutch rod 6A is in the normal connection posture and the normal disconnection posture, the left rotation shaft 61 is maintained in the normal state in which the left rotation shaft support member 51 extends "the handle left-right".

As shown in FIG. 16, when no load is applied to the left rotary shaft 61, a play (gap) is formed between the outer periphery of the left rotary shaft 61 and the inner periphery of the connection portion through hole 59. Further, the size of the inner periphery of the left side plate through hole 60 is sufficiently larger than the size of the outer periphery of the collar 63. Due to such a structure, when a load for moving the left side rotation shaft 61 in a predetermined direction is externally applied to the end portion of the left side rotation shaft 61 on the right side of the handle, the left side rotation shaft support member 51 is provided. Within the range of elastic deformation and within the range where the movement of the left side rotation shaft 61 is restricted by the connection portion through hole 59, the left side rotation shaft support member 51 is elastically deformed and the left side rotation shaft support member 51 is used as a fulcrum. The left rotary shaft 61 is allowed to rotate, and the position of the end portion of the left rotary shaft 61 shifts in a predetermined direction while receiving the force of pushing back by the elasticity of the left rotary shaft support member 51. The normal state of the left rotation shaft 61 changes according to the change.

As shown in FIGS. 14 to 16 (particularly FIG. 14), a plate-shaped left-side rotating shaft connecting member 50 is provided at the handle front side end of the left vertical clutch rod portion 16AL so as to face the handle lower side. It is extended and provided. The left rotary shaft connecting member 50 is formed with a left rotary shaft through hole 66 (FIG. 16) through which the left rotary shaft 61 penetrates, and the left rotary shaft 61 penetrates through the left rotary shaft through hole 66. .. As shown in FIG. 16, the inner circumference of the left rotation shaft through hole 66 is formed larger than the outer circumference of the left rotation shaft 61, and a play (gap) is formed between the inner circumference and the outer circumference. There is. As shown in FIGS. 15 and 16, the left rotation shaft 61 is provided at the front end thereof on the right side of the handle with a removal prevention portion 65 for preventing the left rotation shaft connection member 50 from falling off.

As shown in FIG. 14, the end portion of the clutch wire 67 is connected to the surface of the left rotary shaft connecting member 50 on the right side of the handle via the clutch wire connecting member 68. Similar to the first embodiment, when the state of the handle rod 5A and the clutch rod 6A is in the normal connection posture, the clutch wire 67 is pulled to connect the clutch 7, and in the case of the normal disconnection posture, the clutch wire 67 returns to its original state. The clutch 7 is disengaged.

17, FIG. 18, FIG. 19, FIG. 20(A), and FIG. 21(A) are diagrams used to describe the right side clamping pressure safety mechanism 1AR. FIG. 17 is a perspective view of the right side pinching safety mechanism 1AR as viewed in the direction indicated by the arrow Y4 in FIG. FIG. 18 is a diagram of the right side pinching safety mechanism 1AR as viewed from the lower side of the handle toward the upper side of the handle. 19 is a sectional view taken along line BB of FIG. FIG. 20(A) is a diagram of the right side pinching safety mechanism 1AR as viewed from the left side of the handle toward the right side of the handle. 21A is a view of a cross section near the position P2 in FIG. 14 as viewed from the front side of the handle toward the rear side of the handle. Note that FIGS. 20B and 21B are used in the description below. Further, in each of FIGS. 19, 20, and 21, the drawing of the guide plate 70 (described later) is omitted.

As shown in FIG. 17, at a predetermined position of the right vertical handle rod portion 14AR, a plate-like right side support portion fixing member 71 has one surface facing the right side of the handle and the other surface 71a of the handle left side. It is attached so that it faces you. Specifically, as shown in FIG. 17 and other figures, the upper end portion of the right side support portion fixing member 71 is provided with a bolt and a nut that are spaced apart in the “handle front-rear” direction from the right longitudinal handle. It is firmly fixed to the rod portion 14AR.

As shown in FIGS. 18, 19 and 21(A), the outer surface of the right side support portion fixing member 71 has a substantially frustoconical right rotation shaft support member 58 (with a hollow inside (see FIG. 19)). (Corresponding to the "first rotary shaft support member" in the claims) is attached. The right rotary shaft support member 58 has a bottom surface fixed to a flat plate-like base member, and the base member is fixed to the right side support portion fixing member 71 by two bolts and nuts. That is, the right rotation shaft support member 58 is fixed to the right support portion fixing member 71. The right rotary shaft support member 58 is configured by an elastic member (rubber member in this embodiment) having elasticity. In particular, the right rotary shaft support member 58 is made of a rubber member that is more elastically deformable than the rubber member that forms the left rotary shaft support member 51 and that is softer than the left rotary shaft support member 51.

As shown in FIG. 17, FIG. 18, FIG. 20(A), and FIG. 21(A) (particularly, FIG. 19 and FIG. 21(A)), the center axis of the right rotation shaft support member 58 has a rod-shaped right rotation. The shaft 72 (corresponding to the “first rotating shaft” in the claims) is inserted, and the right rotating shaft 72 is supported by the right rotating shaft support member 58. Specifically, a right side plate through hole 73 (FIG. 19) penetrating the right side supporting part fixing member 71 is formed in a portion of the right side supporting part fixing member 71 corresponding to the central axis of the right rotating shaft supporting member 58. The hollow inside the right rotary shaft support member 58 is exposed through the right side plate through hole 73. The right rotation shaft 72 passes through the right side plate through hole 73 and the cavity inside the right rotation shaft support member 58, and moves the right support portion fixing member 71 and the right rotation shaft support member 58 in the “handle left-right” direction. Penetrates. A nut 58a is screwed into a portion of the right rotation shaft 72 protruding from the right rotation shaft support member 58 toward the right side of the handle, and the right rotation shaft 72 is fixed to the right rotation shaft support member 58. .. As shown in FIG. 19, the inner circumference of the right side plate through hole 73 is sufficiently larger than the outer circumference of the right side rotating shaft 72. Further, in FIG. 19, reference numeral 58b denotes a metal part made of metal that forms the right rotation shaft support member 58 integrally with the rubber member, and as shown in FIG. 19, the right rotation shaft 72 has the metal portion 58b. Through a through hole formed in the center of the handle, and protrudes toward the right side of the handle. A nut 58a is screwed into the protruded portion. When the clutch rod 6A is in the normal connection posture and the normal disconnection posture, the right rotation shaft 72 is maintained in the normal state in which the right rotation shaft support member 58 extends "handle left side-right side".

Due to such a structure, when a load for moving the right rotation shaft 72 in a predetermined direction is externally applied to the end portion of the right rotation shaft 72 on the left side of the handle, the right rotation shaft support member 58 is provided. Within the range of elastic deformation of the right rotation shaft support member 58, the right rotation shaft support member 58 is elastically deformed to allow the right rotation shaft 72 to rotate about the right rotation shaft support member 58 as a fulcrum. The position of the end portion of the right rotation shaft 72 shifts in a predetermined direction while receiving a pushing force due to elasticity. The normal state of the right rotating shaft 72 changes according to the change.

As shown in FIG. 17, FIG. 18, FIG. 19, FIG. 20(A), and FIG. 21(A) (particularly, FIG. 18 and FIG. 19), the right vertical handle rod 14AR has a handle at a predetermined position. A plate-shaped switch support member 74 having a portion extending to the left and a portion bending from the portion toward the rear of the handle and extending toward the rear of the handle is fixed by adhesion, welding, or the like. There is. Two rod-shaped intermediary members 75 extending toward the lower side of the handle are provided at an end portion of the switch support member 74 on the left side of the handle so as to be separated from each other in the “front-back side of the handle”. A switch 76 is attached to the switch support member 74 via the two intermediary members 75.

The switch 76 includes a switch base end portion 77 supported by the intermediary member 75, and a switch lever 78 (corresponding to an “operator” in the claims) protruding from the switch base end portion 77 toward the right side of the handle. Have. The switch 76 is a limit switch, and the switch lever 78 rotates about the switch base end portion 77 as a center portion in an arbitrary rotation direction within a certain range. The shape of the switch lever 78 is a tapered shape in which a certain distance has the same diameter from the switch base end portion 77 toward the right side of the handle, and the diameter gradually decreases after the certain distance.

When no load is applied to the switch lever 78 (states of FIGS. 17, 18, 19, 20(A) and 21(A)), the switch 76 is in the off state. On the other hand, when a load for moving the switch lever 78 is applied to the switch lever 78 and the switch lever 78 rotates about the switch base end portion 77 as a center portion in an arbitrary rotation direction by a certain amount or more, The switch 76 is turned on (operating state). When the switch 76 is turned on, the operation of the power source is stopped, the supply of power from the power source to the drive unit is stopped, and the drive of the drive unit is stopped accordingly. For example, when the switch 76 is turned on, power supply to the power source by the power supply device that supplies power to the power source is stopped. Further, for example, when the walkable work vehicle 2A has an engine-type power source, the power supply to the spark plug is cut off when the switch 76 is turned on. In addition, in each drawing, the illustration of the signal line that outputs the signal from the switch 76 is omitted.

As shown in FIGS. 17, 18, 20(A), and 21(A), a right rotation shaft connecting member 80 is provided at the handle front end of the right vertical clutch rod portion 16AR. There is. The right rotary shaft connecting member 80 includes a downward extending portion 81 extending downward from the handle on the left side of the handle of the right vertical clutch rod portion 16AR, and a forward extending portion from the downward extending portion 81 toward the front of the handle. The front extension part 82 is bent and extends toward the front of the handle. A right rotary shaft through hole 83 (see FIG. 24 described later) through which the right rotary shaft 72 penetrates is formed at the tip of the front extending portion 82, and the right rotary shaft 72 passes through the right rotary shaft through hole 83. Penetrates. The inner circumference of the right rotation shaft through hole 83 is formed larger than the outer circumference of the right rotation shaft 72, and a play (gap) is formed between the inner circumference and the outer circumference. A removal prevention member 72a for preventing removal of the right rotation shaft connecting member 80 is provided at the tip of the right rotation shaft 72 on the left side of the handle.

In the front extending portion 82 of the right rotation shaft connecting member 80, a contact portion 85 (a contact portion 85 that moves in association with the movement of the clutch rod 6A) is formed in front of the right rotation shaft through hole 83. ing. FIG. 22 is a view of the right rotation shaft connecting member 80 when the posture of the clutch rod 6A is in the normal connection posture as viewed from the left side of the handle toward the right side of the handle in order to explain the contact portion 85. In FIG. 22, the position of the switch lever 78 at the positions corresponding to the positions of the first contact portion 86 and the second contact portion 87 (both of which will be described later) is clearly shown.

The contact portion 85 will be described in detail. As shown in FIG. 22, the contact portion 85 has a surface (thickness of the front extending portion 82) facing the switch lever 78 behind the switch lever 78 and behind the handle. , A first contact portion 86 extending in a region on the rear side of the handle of the switch lever 78. Further, the contact portion 85 has a surface facing the switch lever 78 (thickness of the front extending portion 82) below the switch lever 78 and extends to a region of the switch lever 78 on the handle lower side. It has a second contact portion 87. The second contact portion 87 is slightly inclined toward the front of the handle as it extends toward the front of the handle.

As shown in FIG. 22, when the clutch rod 6A is in the normal connection posture (also in the normal disconnection posture), the contact portion 85 does not contact the switch lever 78, but the first contact portion 86 causes the switch to move. At a position close to the lever 78, the switch lever 78 extends to a region on the handle rear side of the switch lever 78, and at a position near the switch lever 78, the second contact portion 87 extends to a region below the handle of the switch lever 78. It will be in the state of doing. As a result, the contact portion 85 extends in the range from the rear of the handle to the lower side of the handle of the switch lever 78. Since the first contact portion 86 draws an arc centered on the axis of the right rotation shaft 72, even if the first contact portion 86 swings between the normal connection posture/normal disconnection posture, It does not come into contact with the switch lever 78.

As shown in FIGS. 17 and 18, a guide plate 70 is provided behind the handle of the downward extending portion 81 of the right rotary shaft connecting member 80. 20(A) and 21(A), the illustration of the guide plate 70 is omitted. The guide plate 70 will be described in detail. On the surface 71a on the left side of the handle of the right side support portion fixing member 71, one surface faces the handle above the lower extension 81 and the other faces below the handle. A flat plate-shaped guide plate 70 facing the surface is provided so as to extend toward the left side of the handle. The base end of the guide plate 70 is fixed to the surface 71a of the right side support portion fixing member 71 by adhesion, welding or the like.

As shown in FIG. 18, the front end portion of the guide plate 70 is formed by cutting out from the side surface of the guide plate 70 on the front side of the handle toward the rear side of the handle so that the width becomes gradually smaller toward the rear side of the handle. The guide groove 88 is formed. When the posture of the clutch rod 6A is the normal connection posture, the side portion of the lower extension portion 81 on the handle rear side is guided so as to be in contact with the deepest portion of the guide groove 88 or to be positioned at a position slightly separated. It will be in a state of entering the groove 88. In this state, the downward extending portion 81 is a state in which the downward extending portion 81 does not incline with respect to the “handle front-rear” direction and extends straight with respect to the direction.

By the way, as described above, when the clamping pressure is generated, an excessive load is applied to the clutch rod 6A in the normal connection posture to rotate the clutch rod 6A in the specified rotation direction KD1, and In some cases, an excessive load is applied to the clutch rod 6A that is in the normal connection posture to move the clutch rod 6A relatively forward with respect to the handle rod 5A.

Here, consider a case where an excessive load for moving the clutch rod 6A forward is applied to the clutch rod 6A. In the present embodiment, as described above, the clutch rod 6A includes the left rotation shaft 61 supported by the left rotation shaft support member 51 made of a rubber member and the right rotation shaft support member 58 made of a rubber member. It is rotatably supported by a right-side rotating shaft 72 supported by. The rubber member forming the left-side rotation shaft support member 51 is harder to elastically deform and harder than the rubber member forming the right-side rotation shaft support member 58.

Due to such a structure, when a load for moving the clutch rod 6A toward the front of the handlebar is applied to the clutch rod 6A in accordance with the occurrence of the clamping pressure, basically, the clutch rod 6A is as shown in FIG. 7(B). In addition, the vehicle moves while leaning to the left with respect to the front of the steering wheel. That is, since the left rotation shaft support member 51 is less likely to be elastically deformed than the right rotation shaft support member 58, when a similar load is applied to both the left rotation shaft 61 and the right rotation shaft 72, The right rotation shaft 72 has a larger movement amount (the rotation amount about the rotation shaft support member), and the clutch rod 6A moves so as to rotate about the left rotation shaft 61 as a whole. Is. Note that, in FIG. 7B, the clutch rod 6A is tilted more than it actually is for the sake of clarity. The same applies to FIG. 7C.

Therefore, as compared with the case where the left rotary shaft support member 51 and the right rotary shaft support member 58 have the same elastic force, when the load for moving the clutch rod 6A forward of the handle is applied, the right rotary shaft is It is possible to effectively increase the amount of displacement of the connecting member 80 in the “direction that includes the component toward the front of the handle”. When a load for moving the clutch rod 6A toward the front of the handle is applied, the left rotary shaft 61 and the right rotary shaft 72 do not rotate by an equal amount of rotation, but the right rotary shaft 72 rotates. This is because it is biased and largely rotates. This contributes to the proper operation of the switch 76 when an excessive load for moving the clutch rod 6A toward the front of the handle is applied, as will become apparent later.

However, when pinching pressure occurs, a very biased load may be applied to the left end portion of the lateral clutch rod portion 17A of the clutch rod 6A. For example, there is a case where a load is applied to the position indicated by the position P3 in FIG. In such a case, as shown in FIG. 7C, the clutch rod 6A tilts to the right with respect to the front of the handle and moves so as to rotate about the right rotation shaft support member 58 as a center portion. In this case, the amount of displacement of the right rotary shaft connecting member 80 to the “direction including the component toward the front of the handle” is limited. In the pinching safety mechanism 1A according to the present embodiment, in both of the case shown in FIG. 7B and the case shown in FIG. Stop driving.

Hereinafter, a case (referred to as case C3) in which an excessive load is applied to rotate the clutch rod 6A in the specified rotation direction KD1, a case in which the state shown in FIG. 7B is set (referred to as case C4), and The operation of the pinching safety mechanism 1A according to the present embodiment will be described for each of the cases (referred to as case C5) in the state of FIG. 7C.

<Case C3>
First, the case C3 will be described. 20(B), an excessive load is applied to the clutch rod 6A from the state of FIG. 20(A) (normally connected posture) to rotate the clutch rod 6A in the specified rotation direction KD1. It is a figure which shows a later state. In FIG. 21B, from the state of FIG. 21A (normal connection posture), an excessive load is applied to the clutch rod 6A to rotate the clutch rod 6A in the specified rotation direction KD1. It is a figure which shows a later state. Here, on the surface of the right vertical clutch rod portion 16AR facing the right vertical handle rod portion 14AR, the right rotary shaft 72 projects toward the right vertical handle rod portion 14AR at a position behind the handlebar. The right fulcrum member 90 is provided. Therefore, when an excessive load is applied to the clutch rod 6A in an attempt to rotate the clutch rod 6A in the specified rotation direction KD1, the right fulcrum member 90 of the clutch lever portion 91 is set with the right fulcrum member 90 as a fulcrum by the lever principle. The part in front of the handle moves toward the upper part of the handle. In response to this, the right rotation shaft connecting member 80 provided in front of the right fulcrum member 90 moves toward the upper side of the handle (see FIGS. 20(B) and 21(B)).

When the right rotation shaft connecting member 80 moves upward in the handle, the end portion of the right rotation shaft 72 on the left side of the handle is pulled upward through the right rotation shaft through hole 83, and the end portion is pulled upward. Move towards. As described above, since the right rotation shaft support member 58 is made of the rubber member having elasticity, when the upward load is applied to the end portion of the right rotation shaft 72 on the left side of the handle, the right rotation shaft support member 58 rotates right side. The shaft support member 58 is elastically deformed, the right rotation shaft 72 is displaced from the normal state, and is rotated about the connection portion with the right rotation shaft support member 58, so that its end portion moves upward. To do.

In this embodiment, the elastic force of the right rotary shaft support member 58 is hardly elastically deformed by the load applied to the clutch rod 6A during normal use, and the state of the right rotary shaft 72 relative to the right rotary shaft support member 58 is almost displaced. Without maintaining the normal state, on the other hand, when an excessive load that may cause pinching is applied to the clutch rod 6A and a load that pushes up this shaft is applied to the right rotary shaft 72, The elastic force is such that the state of the right rotary shaft 72 with respect to the right rotary shaft support member 58 is changed in accordance with the action of the load to change the normal state. The elastic force of the right rotating shaft support member 58 is not limited to the elastic force of the material of the rubber member, but also the shape of the right rotating shaft support member 58, the mode of the connecting portion with the right rotating shaft 72, and other elements. In consideration of the above, it means a force that tries to keep the right-side rotating shaft 72 at the current position against the load from the outside. The same applies to the left rotary shaft support member 51.

When the end of the right-side rotating shaft 72 on the left side of the handle moves upward, the second contact portion 87 of the right-side rotating shaft connecting member 80 contacts the tip of the switch lever 78 from the lower side of the handle. .. When the end portion further moves upward, the tip portion of the switch lever 78 is pushed up by the second contact portion 87. Then, when the switch lever 78 is pushed up by a certain amount or more, the switch 76 in the off state is turned on, and the driving of the drive unit is stopped.

As described above, in case C3, when an excessive load is applied to the clutch rod 6A in the normal rotation direction KD1 in the normal connection posture, the right rotation shaft support member 58 elastically deforms to support the right rotation shaft. The front end of the right rotary shaft 72 moves upward with the member 58 as a fulcrum, and the clutch rod 6A supported by the right rotary shaft 72 moves with this movement, and the clutch rod 6A moves in accordance with the movement of the clutch rod 6A. 6A comes into contact with the switch 76 to activate the switch 76 and stop the operation of the power source. The time from the timing when an excessive load is applied to the clutch rod 6A to the timing when the switch 76 is turned on is very short.

<Case C4>
Next, case C4 will be described. As described above, the case C4 is a case in which the clutch rod 6A moves to the front side of the steering wheel while tilting to the left side of the steering wheel as shown in FIG. FIG. 23 is a diagram of the right side pinching safety mechanism 1AR after the excessive load for moving the clutch rod 6A is applied to the clutch rod 6A in the case C4, as viewed from the upper side of the handle toward the lower side of the handle. FIG. 23 shows a state in which the right vertical clutch rod portion 16AR has moved substantially straight toward the front of the steering wheel. In case C4, the right vertical clutch rod portion 16AR moves to the front side of the steering wheel while tilting to the left of the steering wheel. However, as described above, the movement direction includes many components directed toward the front side of the steering wheel. The amount of forward movement is large enough. Therefore, in case C4, when an excessive load is applied, each member is in the same state as in FIG. 23, and the right side clamping safety mechanism 1AR operates in the same manner as the operation described below.

In case C4, when an excessive load is applied to the clutch rod 6A to move the clutch rod 6A forward of the handlebar, the right rotary shaft connecting member 80 moves in front of the handlebar (more To be precise, it is a direction that includes many components toward the front of the steering wheel (hereinafter, simply referred to as the front of the steering wheel). As described above, since the right rotation shaft support member 58 is made of the rubber member having elasticity, when the load toward the front of the handle is applied to the right rotation shaft connection member 80, the right rotation shaft support member 58 is moved. The right rotation shaft 72 is elastically deformed, and the right rotation shaft 72 rotates around the right rotation shaft support member 58, so that the end portion thereof moves toward the front of the handle and changes from the normal state.

As the right rotation shaft connecting member 80 moves toward the front of the handle, the first contact portion 86 of the right rotation shaft connecting member 80 contacts the tip of the switch lever 78 from the rear side of the handle. When the right rotation shaft connecting member 80 further moves forward, the tip of the switch lever 78 is pushed toward the front of the handle. Then, when the switch lever 78 is pressed by a certain amount or more, the switch 76 in the off state is turned on (the state in FIG. 23), and the driving of the drive unit is stopped.

As described above, in the present embodiment, due to the difference between the elastic force of the right rotary shaft support member 58 and the elastic force of the left rotary shaft support member 51, the load for moving the clutch rod 6A forward is applied. The right rotation shaft connecting member 80 is structured to easily move to the front of the steering wheel (in a direction including a large amount of components in front of the steering wheel) when the steering wheel is turned on. That is, as compared with the case where the right rotation shaft support member 58 and the left rotation shaft support member 51 have the same elastic force, the movement amount of the right rotation shaft connection member 80 when the same load is applied to the clutch rod 6A. Is big. With such a configuration, the switch 76 can be accurately turned from the off state to the on state when the clamping pressure is generated.

<Case C5>
Next, case C5 will be described. As described above, the case C5 is a case in which the clutch rod 6A moves to the front side of the steering wheel while tilting to the right of the steering wheel as shown in FIG. In the case of this case C5, the right rotation shaft connecting member 80 moves only in the direction including the component toward the front of the steering wheel, while the clutch rod 6A moves due to the inclination to the right toward the front of the steering wheel. ..

FIG. 24 is a diagram of the right side clamping safety mechanism 1AR after an excessive load is applied to the clutch rod 6A in the case C5, as viewed from substantially the same direction as FIG. FIG. 25 is a diagram of the right side pinching safety mechanism 1AR after an excessive load is applied to the clutch rod 6A in the case C5, as viewed from the upper side of the handle toward the lower side of the handle. As described above, the guide plate 70 is provided behind the handle of the downward extending portion 81 of the right rotary shaft connecting member 80, and in the normal connection posture, the side portion of the downward extending portion 81 on the handle rear side is provided. The guide groove 70 is located at a position where it abuts on the deepest part of the guide groove 88 formed in the guide plate 70 or is slightly separated therefrom.

When a load for inclining the clutch rod 6A to the right side toward the front of the handlebar is applied to the clutch rod 6A, the side portion on the rear side of the handlebar of the lower extending portion 81 of the right rotary shaft connecting member 80 is indicated by the arrow in FIG. As indicated by Y5, the steering wheel attempts to move toward the left side of the steering wheel (the force to move the steering wheel in the direction indicated by the arrow Y5 acts). Then, as shown by an arrow Y6 in FIG. 25, the side portion on the handle rear side of the downward extending portion 81 slides inside the guide groove 88 and moves in the direction shown by an arrow Y6 in FIG.

With the sliding of the side portion on the handle rear side of the downward extending portion 81 in the direction indicated by the arrow Y6, the right rotation shaft connecting member 80 generally moves in the direction indicated by the arrow Y7 in FIG. The direction indicated by the arrow Y7 is a direction that includes a large number of components that move forward of the handle. As described above, since the right rotation shaft support member 58 is made of the elastic rubber member, when a load in the direction indicated by the arrow Y7 acts on the right rotation shaft connection member 80, the right rotation shaft support member 58 is supported. The member 58 is elastically deformed, the right rotation shaft 72 is rotated around the connection portion with the right rotation shaft support member 58, and its end portion is moved toward the front of the handle to change the normal state. ..

In response to the movement of the right rotation shaft connecting member 80 in the direction indicated by the arrow Y7, the first contact portion 86 contacts the tip portion of the switch lever 78 from the handle rear side. When the right rotation shaft connecting member 80 further moves forward, the tip of the switch lever 78 is pushed toward the front of the handle. Then, when the switch lever 78 is pressed by a certain amount or more, the switch 76 in the off state is turned on (the state of FIGS. 24 and 25), and the driving of the drive unit is stopped. As described above, the right side pinching safety mechanism 1AR according to the present embodiment also stops the driving of the drive unit depending on the possibility of pinching even in the case C5.

<Third Embodiment>
Next, a third embodiment will be described. Here, in the above-described second embodiment, in the left side clamping safety mechanism 1AL, the left side rotation shaft 61 is supported by the left side rotation shaft support member 51 formed of an elastic member. Further, in the second embodiment, the left-side rotating shaft 61 supports the left-side rotating shaft connecting member 50 that moves in conjunction with the clutch rod 6A. A clutch wire connecting member 68 is attached to the left rotary shaft connecting member 50, and when the clutch rod 6A is in the normal connecting posture, the clutch wire 67 is pulled to connect the clutch 7. This structure has the following improvements.

FIG. 26 is a diagram showing the above-described structure of the second embodiment in a simplified manner for convenience of description. In each drawing of FIG. 26, reference numeral 1X indicates a rotary shaft supporting member formed of an elastic member, reference numeral 2X indicates a rotary shaft supported by the rotary shaft supporting member 1X, and reference numeral 3X indicates a connecting member supported by the rotary shaft 2X. Reference numeral 4X is a clutch rod integrally formed with the connecting member 3X, reference numeral 5X is a clutch wire connecting member attached to the connecting member 3X, and reference numeral 6X is a clutch wire connecting to the clutch wire connecting member 5X. Showing. The clutch rod 4X in FIG. 26(A) is in the normal disengagement posture, and the clutch rod 4X in FIG. 26(B) is in the normal engagement posture.

As shown in FIG. 26(B), when the clutch rod 4X is in the normal connection posture, the relative position of the clutch wire connecting member 5X with respect to the rotating shaft 2X is displaced, and the clutch wire 6X is pulled. At this time, a strong tension is applied to the clutch wire 6X, and due to this, a tension that pulls in the direction indicated by the arrow YJ1 in the drawing is applied to the clutch wire coupling member 5X. In the following description, the clutch wire (the clutch wire 6X in this example, the clutch wire 103 in the third embodiment) is pulled, and the tension is applied to the clutch wire, whereby the direction of the tension applied to the end portion of the clutch wire. Is referred to as "first direction YJ1".

Due to the tension in the first direction YJ1 applied by the clutch wire 6X, a force for moving the connecting member 3X in the first direction YJ1 is applied, and further to the rotating shaft 2X supporting the connecting member 3X. Also, a tension is applied to move the tip portion in the first direction YJ1. Then, due to the force of the first direction YJ1 applied to the rotating shaft 2X in the normal connecting posture, the tip of the rotating shaft 2X may slightly move in the first direction YJ1 when the normal connecting posture is achieved. Here, the rotating shaft 2X functions as a pivot for rotation of the clutch rod 4X, and its posture is maintained while the clutch rod 4X is normally moving between the normal connecting posture and the normal disconnecting posture. Is desired to remain unchanged. When the rotation shaft 2X, which is a support shaft, moves in accordance with the movement of the clutch rod 4X, the clutch rod 4X not only rotates about the support shaft, but also moves the rotation shaft 2X in the first direction YJ1 side. With this, the entire vehicle moves in the first direction YJ1, which may adversely affect the operability of the clutch rod 4X. That is, in the structure of FIG. 26, the movement of the tip of the rotary shaft 2X that occurs when the body is in the normal connection posture may adversely affect the operability, and there is room for improvement in this respect.

In view of this, in the present embodiment, the clamping safety mechanism 100 is provided with the adjusting mechanism 101, and by this adjusting mechanism 101, when the clutch rod 6B is in the normally connected posture, the clutch wire 103 acts in the first direction YJ1. The tension is prevented from acting on the left rotation shaft 104 (corresponding to the “second rotation shaft” in the claims) (as will be apparent later, in this embodiment, in the first direction). (The direction opposite to YJ1 acts on the left rotation shaft 104). Hereinafter, the pinching safety mechanism 100 according to the present embodiment will be described in detail. However, in the following description, elements that are the same as in the first embodiment will be assigned the same reference numerals as in the first embodiment, and detailed description thereof will be omitted. Further, the configuration of the walk-behind work vehicle 2B to which the pinching safety mechanism 100 according to the third embodiment is applied is basically the same as that of the first embodiment except for the portion related to the pinching safety mechanism 100. Regarding the configuration of the main body of the walk-behind work vehicle 2B, FIGS.

FIG. 27 is a perspective view of the handle rod 5B and the clutch rod 6B in the walkable work vehicle 2B as viewed from the upper rear side. In FIG. 27, the left and right fulcrum members 140 (FIGS. 43 and 44) are not shown. This also applies to FIGS. 28 to 32, 34 to 38, and 40 to 42. The left and right fulcrum members 140 have the same function as the left and right fulcrum members 31 of the first embodiment, and the function thereof will be described later with reference to FIG. 43. In FIG. 27, the clutch rod 6B is in the normal disengagement posture. In the present embodiment, front handle, rear handle, left handle, right handle, upper handle, and lower handle are defined as in the first embodiment.

As shown in FIG. 27, the walk-behind work vehicle 2B includes a handle rod 5B and a clutch rod 6B arranged above the handle rod 5B, as in the first and second embodiments. The handle rod 5B includes a left vertical handle rod portion 14BL extending from the vehicle body toward the rear of the vehicle body, a right vertical handle rod portion 14BR, and a lateral handle extending laterally between these handle rod portions. This is a loop-type configuration having a rod portion 15B. Further, the clutch rod 6B is of a loop type having a left vertical clutch rod portion 16BL, a right vertical clutch rod portion 16BR, and a horizontal clutch rod portion 17B that is horizontally stretched between these clutch rod portions. It is a composition. As shown in FIG. 27, the pinching safety mechanism 100 includes a left side pinching safety mechanism 108L provided on the left vertical clutch rod portion 16BL side and a right side pinching safety mechanism 108L provided on the right vertical clutch rod portion 16BR side. And a pressure safety mechanism 108R.

28 to 32 are views used to describe the left side clamping safety mechanism 108L. FIG. 28 is a view of the left side pinching safety mechanism 108L as viewed from the rear side of the handle and slightly from the right side of the handle. FIG. 29 is a diagram of the left side pinching safety mechanism 108L viewed from the rear side of the handle toward the front side of the handle. FIG. 30 is a diagram of the left side pinching safety mechanism 108L viewed from the left side of the handle toward the right side of the handle. FIG. 31 is a diagram of the left side pinching safety mechanism 108L viewed from the right side of the handle toward the left side of the handle. FIG. 32 is a diagram showing the left rotation shaft connecting member 110 (described later) in a transparent manner with respect to FIG. 28 to 32, the clutch rod 6B is in the normal disengagement posture.

As shown in FIGS. 28 to 32, a connecting member 111 is fixed to the tip of the left vertical clutch rod portion 16BL, and the connecting member 111 has a U-shape when viewed from the rear side of the handle. The left-side rotary shaft connecting member 110 (especially see FIG. 29) (corresponding to the “rotary shaft connecting member” in the claims) is connected. The left rotary shaft connecting member 110 includes a portion connected to the connecting member 111, a plate-like first lower extending portion 112 that hangs downward from this portion, and a handle left side of the first lower extending portion 112. And a plate-like second downward extending portion 113 that is located downwardly and hangs downward. A gap is formed between the first lower extension portion 112 and the second lower extension portion 113, and the left rotation shaft support member 114 (the "second rotation shaft support member in the claims" is defined in the gap. ). The details will be described later). In the present embodiment, the left rotary shaft connecting member 110 is configured as a separate member from the left vertical clutch rod portion 16BL, but the left rotary shaft connecting member 110 and the left vertical clutch rod portion 16BL are not included. May be integrally configured.

A left-side rising member 115 is fixed to the left vertical handle rod portion 14BL, and the left-side accommodating member 116 is separated from the left vertical handle rod portion 14BL to the right of the handle by the left-side rising member 115. Supported (see in particular FIGS. 28, 29, 32). The left side accommodation member 116 is supported by the left side rising member 115 in a state of being positioned in the gap between the first lower extension portion 112 and the second lower extension portion 113.

The left side accommodation member 116 is a frame body having a surface on the right side of the handle and a surface on the left side of the handle that are open, and has a width of “the left side of the handle-the right side”. Are accommodated (see especially FIGS. 31 and 32). The left rotation shaft support member 114 supports the left rotation shaft 104. FIG. 33(A) is a diagram showing the left housing member 116, the left rotary shaft support member 114, and the left rotary shaft 104 extracted from FIG. 32. FIG. 33B is a cross-sectional view taken along line CC of FIG. The left rotation shaft support member 114 is configured by an elastic member (rubber member in this embodiment) having elasticity. In particular, the left rotary shaft support member 114 is made of a harder rubber member that is less likely to elastically deform than a rubber member that forms the right rotary shaft support member 118 (described later).

As shown in FIG. 33(A), the left rotation shaft support member 114 is configured by a three-layer rubber member including a left lower elastic member 119, a left middle elastic member 120, and a left upper elastic member 121 facing upward from the handle. Has been done. As shown in FIGS. 33(A) and 33(B), the left-side rotating shaft 104 moves the left-side accommodation member 116 in the “handle left-right direction” direction at the corner behind the handle of the left-side accommodation member 116 and below the handle. The penetrating state is inserted into the left side accommodation member 116. The left rotation shaft 104 is surrounded by the side surface of the left lower elastic member 119 on the handle rear side, a part of the lower surface of the left middle elastic member 120 on the lower side of the handle, and the inner surface of the left housing member 116 while being in contact with each surface. The left lower elastic member 119 and the left middle elastic member 120 press the inner surface of the left housing member 116. Therefore, in a state where no force is applied to the left rotary shaft 104, the left rotary shaft 104 is supported by the left rotary shaft support member 114, and the normal state in which the left handle-right direction is extended is maintained. It

On the other hand, when a strong force toward the front of the handle is applied to the exposed portion of the left-side rotation shaft 104, the left-side rotation shaft 104 moves from the normal state, and the left-side lower-layer elastic member 119 is bent, while the left-side lower-layer elastic member 119 is deformed. It moves toward the front of the handle against the force applied by the member 119. Similarly, when a strong force directed upward from the handle is applied to the exposed portion of the left-sided rotation shaft 104, the left-sided rotation shaft 104 deflects the left-side middle-layer elastic member 120 and the force applied by the left-side middle-layer elastic member 120. Move upwards against the handle. On the other hand, the left rotation shaft 104 does not move toward the lower side of the handle and the rear side of the handle (including the direction included between the lower side of the handle and the rear side of the handle) because the movement is restricted by the inner surface of the left side accommodation member 116. ..

In the present embodiment, the left-side rotation shaft support member 114 and related members are configured as described above, so that when the left-side rotation shaft support member 114 moves to the front of the handle, the left-side lower layer elastic member 119 mainly moves. When the left rotary shaft support member 114 moves above the handle, the left middle elastic member 120 mainly resists this movement. Therefore, by independently adjusting the hardness and the elastic force of the left lower elastic member 119 and the left middle elastic member 120 (of course, the hardness and elastic force of the left upper elastic member 121 may be taken into consideration), It is possible to independently adjust the strength of resistance to the upward movement of the left rotation shaft 104 (difficulty of movement) and the strength of resistance to the forward movement of the handle (difficulty of movement). it can. The effect of this will be described later.

An end portion on the right side of the handle of the left rotary shaft 104 supported by the left rotary shaft support member 114 has a first connecting member through hole 122 (formed in a substantially central portion in the vertical direction of the first lower extending portion 112). 28, 31). Further, the end portion on the left side of the handle of the left rotation shaft 104 is inserted into a second connecting member through hole 123 (FIG. 37 described later) formed in a substantially central portion in the vertical direction of the second lower extension portion 113. It As a result, the clutch rod 6B connected to the left rotary shaft connecting member 110 via the left rotary shaft 104 is in a state of being rotatably supported by the handle rod 5B.

In the first downward extending portion 112, the first connecting member through hole 122 extends below the handle in the normal blocking posture and extends along “the handle upward-downward” in the normal blocking posture, and the first downward extending portion 112. A first guide notch 124 (corresponding to the "guide notch" in the claims) is formed so as to penetrate through the groove. A second guide notch 125 (corresponding to the “guide notch” in the claims) having a similar shape is provided at a position corresponding to the first guide notch 124 in the second downward extending portion 113. Has been formed.

A pair of first shaft support member 126 and second shaft support member 127 are fixed to the lower surface of the left side accommodation member 116. The first shaft support member 126 and the second shaft support member 127 face each other with a gap formed therebetween, and rotate behind the handle of the left rotary shaft connecting member 110 and extend in the “handle left-right” direction. The member shaft 128 is supported. Since the first shaft support member 126 and the second shaft support member 127 are fixed in a stationary state with respect to the left housing member 116, the rotation member shaft for the left vertical handle rod portion 14BL (handle rod 5B). The relative position of 128 is fixed, and regardless of the state of the clutch rod 6B, the relative position of the rotating member shaft 128 with respect to the left vertical handle rod portion 14BL is the same.

A rotating member 129 is rotatably supported by the rotating member shaft 128. The rotating member 129 is a thin plate-like member that is bent at a position biased to the upper end 130 of the rotating member, which is one end with respect to the center. In addition, the shape of the rotating member 129 makes the positional relationship between the clutch wire connecting member 132 (described later) and the insertion portion 136 (described later) appropriate, and the process in which the clutch rod 6B rotates from the normal disconnecting posture to the normal connecting posture. Thus, the amount by which the clutch wire 103 is pulled with respect to the amount of rotation is designed to be appropriate. A through hole is formed in the bent portion of the rotating member 129, and the rotating member shaft 128 is inserted into this through hole, whereby the rotating member 129 is axially supported by the rotating member shaft 128. There is. A restricting member 131 (see FIGS. 28 and 29) that restricts movement of the rotating member 129 in the rotating member shaft 128 in the “left-right direction of the handle” is inserted through the rotating member shaft 128. Movement of the rotating member 129 on the rotating member shaft 128 in the “handle left-right” direction is restricted.

The upper end 130 of the rotating member is an end of the both ends of the rotating member 129 that is located on the upper side of the handle when the clutch rod 6B is in the normal disengagement posture. One end of a rod-shaped clutch wire connecting member 132 extending in the “handle left-right” direction is connected to the upper end 130 of the rotating member. The other end of the clutch wire connecting member 132 is located behind the handle of the left rotary shaft connecting member 110 and beyond the second downward extension 113 to the left of the handle. The wire end 133 of the clutch wire 103 is connected to the.

Of the both ends of the rotating member 129, the rotating member lower end portion 135, which is the end opposite to the rotating member upper end portion 130, has a rod-shaped insertion extending in the “handle left-right” direction. The portion 136 is fixed in a penetrating state, and the insertion portion 136 is supported by the rotating member 129 at the lower end portion 135 of the rotating member. An end portion of the insertion portion 136 on the right side of the handle passes through the first guide notch 124 formed in the first lower extending portion 112 and exceeds the notch to the right side of the handle, and "Handle left-right" in a state in which the end portion on the left side of the handle passes through the second guide notch 125 formed in the second lower extending portion 113 and extends to the left side of the notch handle. Extending in the direction (see in particular FIGS. 28 and 29).

Under the above structure, the rotating member shaft 128, the rotating member 129 pivotally supported by the rotating member shaft 128, and the members associated with these members function as the adjusting mechanism 101. Then, when the clutch rod 6B shifts from the normal disconnecting posture to the normal connecting posture, each member operates in the following modes by the function of the adjusting mechanism 101, and exhibits the following functions.

FIG. 34 is a diagram showing the left-side pinching safety mechanism 108L in a state where the normal shut-off posture is being changed to the normal connecting posture, and FIG. 35 is a diagram showing the left-side pinching safety mechanism 108L in the normal connecting posture. Is. 34 and 35 both correspond to FIG. 32, and time elapses in the order of FIG. 32→FIG. 34→FIG. 35 from the normal shut-off posture to the normal connection posture. 36 and 37 are diagrams showing the left side clamping pressure safety mechanism 108L in the normal connection posture. FIG. 36 corresponds to FIG. 28, and FIG. 37 corresponds to FIG.

As shown in FIG. 34, when the clutch rod 6B turns in the specified turning direction KD1 from the normal disconnecting posture to the normal connecting posture, the left rotary shaft connecting member 110 fixedly connected to the clutch rod 6B also clutches. The left rotation shaft connecting member 110 rotates in the specified rotation direction KD1 about the left rotation shaft 104 in conjunction with the rod 6B. Focusing on the first lower extension 112 that constitutes the left rotation shaft connecting member 110, when the first lower extension 112 rotates about the left rotation shaft 104 in the specified rotation direction KD1, the first guide cut portion is formed. The notch 124 also maintains the state in which the left-side rotating shaft 104 (strictly, a portion slightly on the front side of the handle relative to the left-side rotating shaft 104) is positioned on an imaginary line connecting the lower end portion 138 and the upper end portion 139 thereof. The lower end portion 138 rotates while changing its posture so as to draw an arc having a larger radius than the upper end portion 139. The same applies to the second guide notch 125.

As shown in FIG. 34, in response to the rotation (movement) of the first guide notch 124 and the second guide notch 125, the inner surface 137 of the first guide notch 124 on the handle rear side (FIG. 32, 34, 35, 37) come into contact with the insertion portion 136 and gradually push up the insertion portion 136. In response to this, the insertion portion 136 is guided by the first guide notch 124 and the second guide notch 125 to apply a force to the inner surface 137 of these notches in the second direction YJ2 (described later). While sliding, the rotating member 129 rotates in the specified rotating direction KD1 about the rotating member shaft 128 in accordance with the sliding of the insertion portion 136.

In response to the rotation of the rotating member 129, the clutch wire connecting member 132 connected to the upper end 130 of the rotating member and the wire end 133 connected to the clutch wire connecting member 132 are provided on the rear side of the handle. The clutch wire 103 moves in the direction including the components, and the clutch wire 103 is pulled by this. Hereinafter, the direction in which the wire end 133 is pulled is referred to as "second direction YJ2" (Figs. 34, 35, 37). The second orientation YJ2 is the opposite orientation of the first orientation YJ1 (FIGS. 34, 35, 37). When the wire end portion 133 is pulled in the second direction YJ2, a tension acts in the first direction YJ1 as a reaction force. As shown in FIGS. 35 to 37, when the clutch rod 6B is in the normal connection posture, the clutch wire 103 is sufficiently pulled and the clutch 7 is engaged.

As described above, according to the configuration of the present embodiment, the clutch wire 103 is gradually pulled in accordance with the movement of the clutch rod 6B in the process in which the clutch rod 6B shifts from the normal disconnecting posture to the normal connecting posture, and the clutch rod The clutch 7 can be engaged when the 6B is in the normal engagement position. In addition, the configuration of the present embodiment has the following effects.

When the clutch wire 103 is pulled in the process of the clutch rod 6B shifting from the normal disconnecting posture to the normal connecting posture, the clutch wire 103 acts as a reaction force of the force pulling the wire in the second direction YJ2. Is generated in the first direction YJ1. This force becomes stronger as the clutch rod 6B approaches the normal connection posture. In the structure described with reference to FIGS. 26A and 26B, this force indirectly acts on the rotating shaft 2X and causes the rotating shaft 2X to slightly move in the normal connection posture.

On the other hand, in the present embodiment, the posture of the left rotation shaft connecting member 110 (the first lower extension portion 112 and the second lower extension portion 113) according to the movement of the clutch rod 6B from the normal disconnection posture to the normal connection posture. Is displaced in the above-described manner, the insertion portion 136 slides on the inner surface 137 of each notch toward the upper end 139 from the lower end 138 of the first guide notch 124 and the second guide notch 125. While moving while applying a force toward the second direction YJ2 to the inner surface 137. As a result, the left rotating shaft 104 is not acted on by the clutch wire 103 to move in the first direction YJ1, but is applied in reverse to the second direction YJ2. As described above, the left-side rotating shaft 104 is restricted from moving toward the rear of the handle (the direction corresponding to the second direction YJ2) by the left-side housing member 116, so that the left-side rotating shaft 104 moves in the second direction YJ2 relative to the left-side rotating shaft 104. The left rotating shaft 104 does not move even if a force is applied. Therefore, during the movement of the clutch rod 6B from the normal disconnecting posture to the normal connecting posture, the position change due to the clutch wire 103 does not occur.

38 to 42 are views used to describe the right side pinching safety mechanism 108R. FIG. 38 is a view of the right side pinching safety mechanism 108R as viewed from the right side of the handle toward the left side of the handle. FIG. 39 is a diagram in which a part of the right vertical handle rod portion 14BR in FIG. FIG. 40 is a view of the right side pinching safety mechanism 108R as viewed from the left side of the handle toward the right side of the handle. FIG. 41 is a view of the right side pinching safety mechanism 108R as viewed from below the handle and slightly from the right side of the handle. FIG. 42 is a view of the right side pinching safety mechanism 108R as viewed from the lower side of the handle toward the upper side of the handle. 38 to 42, the clutch rod 6B is in the normal connection posture.

As shown in FIGS. 38 to 42, a right-side upright member 141 is fixed to the right vertical handle rod 14BR, and the right-side upright member 141 moves the right vertical handle rod 14BR to the left side of the handle. The right side accommodation member 142 is supported at the separated positions. The right side accommodation member 142 is a frame body having a surface on the right side of the handle and a surface on the left side of the handle that are open, and has a width in the “handle left side-right side” direction. 118 (corresponding to the "first rotating shaft support member" in the claims) is accommodated.

Inside the right side accommodation member 142, the right side rotation shaft 143 (corresponding to the “first rotation shaft” in the claims) extends in the “handle left side-right side” direction at the corners behind and below the handle. It is inserted as it is. The right side of the right rotation shaft 143 extends beyond the surface of the right side rotation shaft support member 118 on the right side of the handle to the right side of the handle. The left side of the right rotation shaft 143 extends beyond the surface of the right side rotation shaft support member 118 on the left side of the handle to the left side of the handle.

The right rotation shaft support member 118 is configured by a right lower layer elastic member 144, a right middle layer elastic member 145, and a right upper layer elastic member 146. The right rotation shaft 143 is supported by the side surface of the right lower elastic member 144 on the handle rear side and a part of the lower surface of the right middle elastic member 145 on the lower side of the handle while being pressed against the inner surface of the right housing member 142. Therefore, when no force is applied to the right rotation shaft 143, the right rotation shaft 143 is maintained in the normal state in which it extends in the “handle left-right” direction. Due to such a configuration, similarly to the left rotation shaft support member 114, the hardness and elastic force of the right lower elastic member 144 and the right middle elastic member 145 (obviously, the hardness and elastic force of the right upper elastic member 146 are added. May be adjusted independently, the strength of resistance to the movement of the right side rotation shaft 143 above the handle (difficulty of movement) and the strength of resistance to movement to the front of the handle (movement). It can be adjusted independently.

As shown in FIGS. 38 to 42, a right side rotating shaft connecting member 148 is connected to a tip end portion of the right vertical clutch rod portion 16BR. The right rotary shaft connecting member 148 has a portion fixed to the front end portion of the right vertical clutch rod portion 16BR, and a plate-like right lower extension portion 149 hanging downward from the handle from this portion. .. A hole is formed in the surface on the right side of the handle of the right lower extension 149, and the end of the right rotation shaft 143 on the right side of the handle is inserted into the hole, whereby the right lower extension 149 is inserted. A clutch rod 6B connected to the right lower extension 149 is supported by the right rotary shaft 143.

A switch 150 is attached to a surface of the right-side rising member 141 on the right side of the handle, on the rear side of the handle with respect to the right-side accommodation member 142. The switch 150 includes a push-down button 151. The switch 150 is in an off state when the button 151 is pressed, and is in an on state when the button 151 is not pressed. When the switch 150 is turned on, the operation of the power source is stopped, the supply of power from the power source to the drive unit is stopped, and the drive of the drive unit is stopped accordingly. An example of the method of stopping the driving of the driving unit when the switch 150 is turned on is as described in the first and second embodiments.

As shown in FIGS. 39, 41 and 42, the button 151 of the switch 150 is provided on a side surface of the housing of the switch 150 on the front side of the handle and at a position corresponding to the position where the right rotation shaft 143 is arranged. There is. Then, in the normal connection posture, the button 151 of the switch 150 is pressed by the end portion of the right rotation shaft 143 on the right side of the handle, and the switch 150 is turned off. Even in the normal blocking posture, or in the state between the normal connection posture and the normal blocking posture, the state of the right rotating shaft 143 hardly changes, and the normal state extending in the “handle left-right” direction is Maintained. In other words, the related members including the right rotation shaft support member 118 are appropriately designed so that such a normal state is maintained. Therefore, as long as the clutch rod 6B is between the normal disconnection posture and the normal connection posture, the button 151 of the switch 150 is kept pressed and the switch 150 is turned off.

43 and 44 are views showing the right side pinching safety mechanism 108R in different states, and correspond to FIG. 39, respectively. As described above, when the clamping pressure is generated, an excessive load is applied to the clutch rod 6B that is in the normal connection posture to rotate the clutch rod in the specified rotation direction KD1, and the normal connection posture. There is a case where an excessive load for moving the clutch rod 6B forward is applied to the clutch rod 6B located at.

Referring to FIG. 43, when an excessive load is applied to rotate the clutch rod in the specified rotation direction KD1, the tip end of the right vertical clutch rod portion 16BR is located above the handle with the fulcrum member 140 as a fulcrum. Move towards. Along with this movement, the right rotation shaft connecting member 148 moves toward the upper side of the handle as a whole, the state of the right rotation shaft 143 connected to the right rotation shaft connection member 148 changes from the normal state, and the right rotation shaft 143. Moves up the handle. As a result, as shown in FIG. 43, the right middle layer elastic member 145 is bent against the drag force of the right middle layer elastic member 145, and the right rotation shaft 143 moves toward the upper side of the handle. Then, the button 151 of the switch 150 is released from the pressing of the right rotation shaft 143, the switch 150 is turned on, and the driving of the drive unit is stopped.

Further, referring to FIG. 44, when an excessive load is applied to the clutch rod 6B which is in the normal connection posture to move the clutch rod 6B forward of the handle relative to the handle rod 5B, the clutch rod 6B is moved. 6B moves forward of the handle relative to the handle rod 5B. Along with this movement, the right rotating shaft connecting member 148 moves toward the front of the handle as a whole, the state of the right rotating shaft 143 connected to the right rotating shaft connecting member 148 changes from the normal state, and the right rotating shaft 143. Moves toward the front of the steering wheel. As a result, as shown in FIG. 44, the right lower elastic layer 144 is bent against the reaction force of the right lower elastic member 144, and the right rotation shaft 143 moves toward the front of the handle. Then, the button 151 of the switch 150 is released from the pressing of the right rotation shaft 143, the switch 150 is turned on, and the driving of the drive unit is stopped.

Here, as described above, the left lower elastic member 119, the left middle elastic member 120, the left upper elastic member 121, and the right lower elastic member 144, which configure the left rotary shaft support member 114, and the right rotary shaft support member 118, respectively. The right middle-layer elastic member 145 and the right upper-layer elastic member 146 can independently adjust their hardness and elastic force. Based on this, based on tests and simulations performed from the viewpoint that the button 151 of the switch 150 is released from the pressing of the right rotation shaft 143 when an excessive load is applied to the clutch rod 6B, each Appropriate members are adopted as the members. As a simple example, according to the configuration of the present embodiment, it is possible to make the right lower elastic member 144 of the right rotary shaft support member 118 harder than the right middle elastic member 145 and less likely to elastically deform. is there. However, the left lower layer elastic member 119 that constitutes the left rotation shaft support member 114 is harder than the right lower layer elastic member 144 that constitutes the right rotation shaft support member 118, and is less likely to elastically deform. Further, the left middle-layer elastic member 120 that constitutes the left rotation shaft support member 114 is harder than the right middle-layer elastic member 145 that constitutes the right rotation shaft support member 118, and is less likely to elastically deform. The effect of this is as described in the second embodiment.

Regarding the second embodiment, by applying the present embodiment, as in the adjusting mechanism 101 according to the present embodiment, the clutch wire 67 acts in the first direction when the clutch rod 6A is in the normal connection posture. You may make it provide the adjustment mechanism which suppresses that tension acts on the left side rotating shaft 61 (2nd rotating shaft) supported by the left side rotating shaft supporting member 51 (2nd rotating shaft supporting member).

Further, by applying the present embodiment to the second embodiment, a load for moving the left side rotation shaft support member 51 and the right side rotation shaft support member 58 in the specified rotation direction KD1 is added to the clutch rod 6A to rotate the left side rotation. When the shaft 61 and the right rotation shaft 72 move, the strength of the resistance applied to the movement and the load to move the handle forward are added to the clutch rod 6A, and the left rotation shaft 61 and the right rotation shaft 72 move. At times, the strength of resistance applied to the movement may be independently adjustable.

Further, the specific structure of the adjusting mechanism 101 is not limited to the structure illustrated in the present embodiment, and when the clutch rod 6B is in the normally connected posture, the tension in the first direction applied by the clutch wire 103 is the left rotation shaft. Any mechanism may be used as long as it suppresses acting on the left-side rotation shaft 104 supported by the support member 114.

Although the three embodiments of the invention have been described above, each of the above embodiments is merely an example of the embodiment for carrying out the invention, and the technical scope of the invention is limited thereby. It should not be construed in a conventional way. That is, the present invention can be implemented in various forms without departing from the gist or the main features thereof.

For example, in the above-described embodiment, the walk-type work vehicle 2 in which the handle bar 5 is attached to the rear of the vehicle body 3 has been described as an example, but the present invention is not limited to this. As an example, a walking type work vehicle configured to be able to switch the mounting direction of the handle rod back and forth by rotating the handle rod around its root portion, and the mounting direction of the handle rod are opposite to those in FIG. The present invention can also be applied to a walk-type work vehicle mounted toward the front of the vehicle body.

Further, for example, in the second embodiment, the structure of the switch 76 is not limited to the illustrated one. That is, any structure may be adopted as long as the contact portion 85 is in contact with the clutch rod 6A by the movement of the right rotary shaft connecting member 80 in response to an excessive load on the clutch rod 6A to be in the ON state. Similarly, the specific structure of the switch 150 in the third embodiment is not limited to that illustrated.

Note that the configuration in which the driving of the drive unit is stopped when an abnormal load is applied to the clutch rod 6 is not limited to the configurations shown in the first, second, and third embodiments. It is sufficient that the supply is stopped and the drive unit is stopped. For example, in the first embodiment, when an abnormal load is applied to the clutch rod 6, the clutch wire 12 operates to disconnect the clutch 7 and cut off the transmission of power from the power source to the drive unit. As a result, the driving of the driving unit is stopped. However, the configuration in which the drive of the drive unit is stopped is not limited to this configuration, and may be any configuration in which the supply of power to the drive unit is stopped by a predetermined means and the drive unit is stopped. As an example, a configuration may be adopted in which a predetermined switch is turned on and the operation of the power source is stopped according to the operation of the clutch wire 12. At that time, the clutch 7 may be disengaged and the operation of the power source may be stopped at the same time.

Further, for example, in the second embodiment, when an abnormal load is applied to the clutch rod 6A, the switch 76 is turned on, the operation of the power source is stopped, and the drive of the drive unit is stopped accordingly. It was configured to do. However, the configuration in which the drive of the drive unit is stopped is not limited to this configuration, and may be any configuration in which the supply of power to the drive unit is stopped by a predetermined means and the drive unit is stopped. As an example, an electromagnetic solenoid is connected in the middle of the clutch wire 67 (not shown) so that the electromagnetic solenoid operates in response to the operation of the switch 76 to bring the clutch into the disengaged state, thereby stopping the drive of the drive unit. It may be configured to. In this case, the clutch may be disengaged and the operation of the power source may be stopped at the same time. In the second embodiment, if the clutch is in the disengaged state, the traveling wheels 4 can be freely rotated even after the pinch safety mechanism 1A stops the movement of the walkable work vehicle 2A. Therefore, it is easy for the worker to leave the space between the walkable work vehicle 2A and the obstacle. The above also applies to the third embodiment having the switch 150.

Further, for example, in the second embodiment, the right rotating shaft connecting member 80 is brought into contact with the switch lever 78 of the switch 76 in accordance with the movement of the right rotating shaft connecting member 80 to turn on the switch 76. In this respect, the right rotation shaft connecting member 80 is always brought into contact with the switch 76 in the normal connection posture, and the switch 76 is not operated in this state, and the load that causes the clutch rod to deviate from the normal connection posture is set. 6A, the right rotary shaft support member 58 is elastically deformed, the contact of the right rotary shaft connecting member 80 is released, and the switch 76 may be activated in this state.

1, 1A, 100 Clamping safety mechanism 2, 2A, 2B Pedestrian work vehicle 3 Vehicle body 5, 5A, 5B Handle rod 6, 6A, 6B Clutch rod 7 Clutch 10 Rotating shaft 11 Bearing 14L, 14AL, 14BL Left vertical direction Handle bar 14R, 14AR, 14BR Right vertical handle bar 15, 15A, 15B Horizontal handle bar 16L, 16AL, 16BL Left vertical clutch bar 16R, 16AR, 16BR Right vertical clutch bar 17 , 17A, 17B Lateral clutch rod portion 26 Insertion portion 30 Spring (biasing member)
36 Holes 38 Wall Members 51, 114 Left Rotation Shaft Support Member (Second Rotation Shaft Support Member)
58, 118 Right rotation shaft support member (first rotation shaft support member)
61, 104 Left rotation shaft (second rotation shaft)
67, 103 Clutch wire 72, 143 Right rotation shaft (first rotation shaft)
76, 150 switch 78 switch lever (operator)
85 contact part 101 adjusting mechanism 110 left side rotary shaft connecting member 124 first guide notch 125 second guide notch 128 turning member shaft 129 turning member 136 insertion part 151 button

Claims (17)

A power source provided in the vehicle body, a drive unit that drives the pair of wheels by the power supplied from the power source, and a clutch that cuts off or transmits power from the power source to the drive unit. Applied to a walk-type working vehicle provided with a handle rod that is gripped and operated by an operator and a clutch rod that is disposed above the handle rod and that is gripped together with the handle rod by the worker to operate the clutch. Is a pinching safety mechanism,
The clutch rod is rotatably supported with respect to the handle rod via a rotation shaft in a prescribed rotation direction approaching the handle rod and in a reverse direction thereof,
When the clutch rod is in the normal connecting posture, which is the normal posture when the clutch is engaged, the state of the rotating shaft is maintained in the normal state, while the specified number of times is exceeded to the extent that it deviates from the normal connecting posture. When a load for moving the clutch rod in a predetermined direction including a moving direction and a direction other than the specified rotation direction is added to the clutch rod, the normal state is configured to change,
A pinching safety mechanism for a walk-behind work vehicle, which is configured to stop the supply of the power to the drive unit according to the change in the normal state. The walkable work vehicle according to claim 1, wherein the predetermined direction includes at least a direction in which the clutch rod relatively moves forward with respect to the handle rod, in addition to the specified rotation direction. Pinching safety mechanism. The clutch rod is rotatably supported by the handle rod via the rotary shaft and the bearing,
When the clutch rod is in the normal connection posture, the state of the bearing and the rotating shaft in the normal state is maintained in a predetermined state, while the specified rotation direction is set to a degree that deviates from the normal connection posture. When a load for moving the clutch rod in a predetermined direction including a direction other than the specified rotation direction is applied to the clutch rod, the predetermined state is released.
The pinching safety mechanism for a walk-type work vehicle according to claim 1 or 2, wherein the power supply to the drive unit is stopped in response to the release of the predetermined state. The rotary shaft is fixed to the clutch rod, has a hole at its tip,
The bearing is fixed to the handle rod, has an insertion portion that can be inserted into the hole,
The predetermined state is an insertion state in which the insertion portion of the bearing is inserted into the hole of the rotary shaft,
When a load that deviates from the normal connection posture is applied to the clutch rod, the insertion state is released, and the position of the rotating shaft with respect to the bearing is changed according to the release of the insertion state, and the rotation The pinching safety mechanism for a walk-behind work vehicle according to claim 3, wherein the clutch is configured to be disengaged as the position of the shaft changes. The insertion portion of the bearing is hemispherical,
The insertion portion of the bearing is biased by a biasing member in a direction approaching the rotating shaft,
When a load that deviates from the normal connection posture is applied to the clutch rod, the hole portion of the rotating shaft pushes the insertion portion of the bearing back against the biasing force of the biasing member and is a hemispherical shape. 5. The walk type work according to claim 4, wherein the insertion part is slidably moved on the surface of the insertion part, and the insertion part is removed from the hole part to release the insertion state. Clamping safety mechanism for vehicles. Around the hole, while restricting the movement from the hole in the direction in which the insertion portion comes out, while providing a wall member for preventing the insertion portion from coming off,
The height of the wall member provided in the direction in which the insertion portion moves with respect to the hole when the load for deviating from the normal connection posture is applied to the clutch rod is provided in a direction other than the direction. The pinching safety mechanism for a walk-type work vehicle according to claim 5, wherein the height is lower than the height of the wall member or the wall member is not provided in the direction. An elastic rotary shaft support member that supports the rotary shaft and is fixed to the handle is provided, and the rotary shaft is normally supported by the rotary shaft support member in the normal connection posture. The above normal condition is maintained,
When a load that deviates from the normal connection posture is applied to the clutch rod, the rotary shaft support member elastically deforms, so that the rotary shaft rotates about the rotary shaft support member as a fulcrum to cause the normal state. Fluctuates, the clutch rod moves in a direction corresponding to the predetermined direction, and the clutch rod operates a switch according to the movement of the clutch rod to stop the operation of the power source. A pinching safety mechanism for a walk-type work vehicle according to claim 1 or 2. The switch has an operating element, and becomes an operating state in response to a change in the state of the operating element,
An abutting portion that moves in conjunction with the movement of the clutch rod in accordance with the movement of the clutch rod in the direction corresponding to the predetermined direction abuts on the operator and changes the state of the operator. The pinching safety mechanism for a walk-type work vehicle according to claim 7, wherein: The handle rod is a loop including left and right vertical handle rod portions extending from the vehicle body toward the rear of the vehicle body, and a horizontal handle rod portion that is laterally bridged between the left and right vertical handle rod portions. Is the composition of the formula,
The clutch rod is rotatably supported with respect to the left and right vertical handle rod portions of the handle rod, and the left and right vertical clutch rod portions extending rearward of the vehicle body from the support points and the left and right clutch rod portions. Is a loop-type structure having a horizontal clutch rod portion that is laterally bridged between the vertical clutch rod portions of
A first rotary shaft support member, a first rotary shaft supported by the first rotary shaft support member, and the switch are provided on one of the left and right vertical clutch rods. A second rotary shaft support member and a second rotary shaft supported by the second rotary shaft support member are provided on the other longitudinal clutch rod portion, while the switch is not provided to deviate from the normal connection posture. When a load is applied to the clutch rod, the switch on the side of the one longitudinal clutch rod portion is configured to operate,
9. The sandwich for a walk-type work vehicle according to claim 7, wherein the second rotary shaft support member is composed of a hard elastic member that is less likely to be elastically deformed than the first rotary shaft support member. Pressure safety mechanism. The clutch rod includes left and right vertical clutch rods extending toward the rear of the vehicle body, and one of the left and right vertical clutch rods has a first rotary shaft support member. A first rotary shaft supported by the first rotary shaft support member and the switch, and a second rotary shaft support member and the second rotary shaft support member on the other longitudinal clutch rod. The second rotary shaft is provided, while the switch is not provided,
On the side of the other longitudinal clutch rod portion, the end portion of the clutch wire is connected to a member that moves in conjunction with the movement of the clutch rod,
It is possible to prevent the tension in the first direction applied by the clutch wire when the clutch rod is in the normal connection posture from acting on the second rotary shaft supported by the second rotary shaft support member. 9. A pinching safety mechanism for a walk-behind work vehicle according to claim 7, wherein an adjusting mechanism is provided. When the load for moving the rotation shaft support member in the specified rotation direction is applied to the clutch rod and the rotation shaft moves, the resistance force applied to the movement and the movement in the predetermined direction. 11. The strength of the resistance applied to the movement when a load is applied to the clutch rod to move the rotary shaft can be independently adjusted. A pinching safety mechanism for a walk-type work vehicle according to item 1. The clutch rod includes a pair of vertical clutch rods extending rearward of the vehicle body, and a rotary shaft formed of an elastic member at the center of rotation of each of the pair of vertical clutch rods. A support member and a rotary shaft supported by the rotary shaft support member are provided.
On one vertical clutch rod side, connect the end of the clutch wire to a member that moves in conjunction with the movement of the one vertical clutch rod,
When the clutch rod is in the normal connection posture, the first tension applied by the clutch wire acts on the rotary shaft supported by the rotary shaft support member on the side of the one longitudinal clutch rod. The pinching safety mechanism for a walk-type work vehicle according to claim 1 or 2, further comprising an adjusting mechanism that suppresses the above-mentioned action. In the process in which the clutch rod is rotated in the specified rotation direction to be in the normal connection posture, the adjusting mechanism causes the end portion of the clutch wire to be opposite to the first direction according to the movement of the clutch rod. 13. The walking type according to claim 12, wherein the tension of the first direction applied by the clutch wire is converted into the second direction and applied to the rotary shaft. A pinching safety mechanism for work vehicles. The one vertical clutch rod portion is integrally formed with the one vertical clutch rod portion, or comprises a rotary shaft connecting member connected to the one vertical clutch rod portion,
The rotary shaft connecting member is rotatably supported by the rotary shaft and has a guide notch,
The adjusting mechanism includes a rotating member shaft fixed to one longitudinal handle rod portion arranged below the one longitudinal clutch rod portion, and a pivotal member rotatably supported by the rotating member shaft. An end portion of the clutch wire is connected to one end portion, and a rotating member provided with an insertion portion that is inserted into the guide notch at the other end portion,
When the clutch rod is rotated in the specified rotation direction toward the normal connection posture, the rotary shaft connecting member moves in accordance with the movement of the clutch rod, and the guide for the guide along with the movement of the rotary shaft connecting member. In accordance with the movement of the notch, the insertion portion is guided by the guide notch and slides while applying a force toward the second direction to the inner surface of the guide notch, and 14. The walk-behind work vehicle according to claim 13, wherein the rotating member rotates about the rotating member shaft in accordance with the sliding to pull the end portion of the clutch wire in the second direction. Pinching safety mechanism for. The handle rod is a loop including left and right vertical handle rod portions extending from the vehicle body toward the rear of the vehicle body, and a horizontal handle rod portion that is laterally bridged between the left and right vertical handle rod portions. Is the composition of the formula,
The pair of vertical clutch rods is a loop-type configuration having left and right vertical clutch rods and a horizontal clutch rod that is laterally bridged between the left and right vertical clutch rods,
A first rotary shaft support member, a first rotary shaft supported by the first rotary shaft support member, and a switch are provided on one of the left and right vertical clutch rods, and the other is provided on the other side. A second rotary shaft support member, a second rotary shaft supported by the second rotary shaft support member, and the adjusting mechanism are provided on the vertical clutch rod portion of the above, while the switch is not provided,
When a load that deviates from the normal connection posture is applied to the clutch rod, the first rotary shaft support member and the second rotary shaft support member are elastically deformed to cause the first rotary shaft and 13. The structure in which the second rotating shaft moves to change the normal state, and the first rotating shaft operates the switch to stop the operation of the power source. 15. A pinching safety mechanism for a walk-type work vehicle according to any one of 1 to 14. When the first rotating shaft is in the normal state, the first rotating shaft presses the button of the switch, while when the first rotating shaft changes from the normal state, the first rotating shaft is 16. The pinching safety mechanism for a walk-type work vehicle according to claim 15, wherein the pressing of the button of the switch by the switch is released to activate the switch. When the load for moving the rotation shaft support member in the specified rotation direction is applied to the clutch rod and the rotation shaft moves, the resistance force applied to the movement and the movement in the predetermined direction. 17. When the load is applied to the clutch rod and the rotary shaft moves, the strength of the resistance applied to the movement can be independently adjusted. A pinching safety mechanism for a walk-behind work vehicle according to item.