JPH0516691A - Safety mechanism of walk-behind work machine - Google Patents

Abstract

(57) [Summary] [Purpose] The work vehicle can be stopped immediately in the event of an unexpected situation such as the worker falling over when going backward. [Configuration] The clutch operating range of the main clutch lever 9 exceeds the dead point DP, the main clutch lever 9 is held in the clutch engaged state, and the main clutch lever 9 is disengaged at a position before the dead point DP. A check and restraint which is configured so as to be biased to return to the position, and which controls the operation of the main clutch lever 9 in the clutch-engaged operation range beyond the dead point DP of the main clutch lever 9 in conjunction with the backward movement of the transmission. A tool 12 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety mechanism for a walk-type working machine for ensuring safety during backward operation of, for example, a walk-type management machine in agricultural machinery.

[0002]

2. Description of the Related Art Conventionally, walking type working machines such as walking type management machines have been known to have the structures shown in (a) and (b) below. (A) As shown in FIG. 4, the main clutch lever 21 and the handle rod 22 are gripped together. (B) Toggle the main clutch lever so that if the clutch is engaged beyond the dead point in the range of its swinging operation, the clutch is held in the engaged state even when the lever is released. The mechanism constitutes the operating mechanism of the main clutch lever.

[0003]

However, in the case of the above-mentioned conventional structure (a), if the main clutch lever 21 that is gripped with the handle is released, the main clutch is disengaged and the traveling is stopped. Although it is highly safe, it was necessary to keep holding the main clutch during running work, and the hand was easily tired. On the other hand, in the above-mentioned conventional structure (b), the main clutch lever is held in the clutch-operated state, so fatigue that keeps holding the lever can be avoided, but an unexpected situation such as a worker falling over during reverse travel occurred. Occasionally, the work machine moves backward without stopping, which is a safety issue.

The present invention has been made in view of the above-mentioned circumstances, and is capable of reducing fatigue during work, but it is also possible to use a work machine when an unexpected situation such as a fall of a worker during reverse travel occurs. An object is to provide a safety mechanism for a walk-behind work machine that can be stopped immediately.

[0005]

In order to achieve the above-mentioned object, a safety mechanism for a walk-behind work machine according to the present invention has the above-mentioned structure in which the main clutch lever is in a clutch-engaged state beyond a dead point in a clutch-engaged state. Configured to the range where the main clutch lever is held and the range where the main clutch lever is urged to return to the clutch disengaged position before the dead point, and is linked to the operation of the transmission to the reverse direction. Then, a check device for checking the operation of the main clutch lever in the clutch engagement operation range beyond the dead point is provided. Further, an abutment member is continuously connected to the main clutch lever so as to be able to move integrally, and the checker fits into the clutch engagement operation range of the main clutch lever at one end of the checker and contacts the main clutch lever. And the first restraint unit that restrains
A second restraint portion at the other end for entering the moving range of the restraining member and coming into contact with the restraining member to restrain the restraint member; and swinging the restraint member around an axial center between the two restraint portions. It may be freely pivoted.

[0006]

In other words, by providing the clutch engagement operation range of the main clutch lever also within the range where the disengagement operation is performed from the dead point in the operation range of this lever,
When the operator is not grasping and operating the main clutch lever, the clutch cannot be operated, and when the vehicle is moving backward, the operator cannot operate the main clutch lever beyond the dead point with the restraining device. If you do not operate the main clutch lever, you will not be able to move backward.At that time, if you release your hand from the main clutch lever, the main clutch lever will return to the clutch disengaged position, and the traveling system of the work machine will lose power and stop traveling. It will be.

[0007]

As described above, according to the present invention, the main clutch lever does not have to be held by hand, and the hand clutch can be held in association with switching between the forward operation and the reverse operation of the transmission. Because you can show the reverse state where you can not run unless you put it,
In order to switch the function of maintaining the clutch engaged state of the main clutch lever between forward and reverse, it is not necessary to separately provide a forward / reverse mode switching means or the like to interlock with the main clutch lever. The composition was obtained.

[0008]

EXAMPLES Examples of the present invention will be described below. In Figure 3,
The walk-type management machine is shown as an example of a walk-type working machine. In this walk-behind management machine, an engine 3 is mounted on a front frame 2 extending forward from a mission case 1, and a belt type transmission mechanism 4 is installed across an output shaft of the engine 3 and an input shaft of the mission case 1. In addition, the drive traveling wheels 5 and 5 are pivotally supported on the lower portion of the mission case 1, and the handle rod 6 extends rearward from the rear portion of the mission case 1.

As shown in FIG. 3, the belt type transmission mechanism 4 is provided with a belt tension clutch 8 as a main clutch, and a main clutch lever for swinging a tension arm 7 of the belt tension clutch 8 is used. As shown in FIG. 3, a handlebar 6 is provided so as to be swingable back and forth. Further, the handle bar 6 is provided with a speed change lever 10 for performing a speed change operation of the speed change device of the transmission case 1, and the speed change device is capable of performing a speed change operation of two forward gear steps and one reverse gear step. I am trying.

As shown in FIGS. 1 and 2, the main clutch lever 9 has a guide groove 11 formed in a guide plate 11 in the front and rear direction.
1a is pivotally attached to a horizontal shaft installed on an operation box A provided on the handle rod 6 so as to be slidably guided back and forth, and a dead point in the middle of the swing operation range set by the guide groove 11a. When the lever is located forward of the DP, the front end of the guide groove 11a is biased toward the crocodile, and when the lever is located rearward of the dead point DP, the rear end of the guide groove 11a is biased toward the crocodile. The spring 16 acts on the main clutch lever 9 to form a toggle mechanism. Further, the main clutch lever 9 is linked by a linkage mechanism (not shown) so that the tension arm 7 can be rockably operated, and the clutch engagement operation range is in front of the dead point DP, the dead point DP and the guide groove. It is set so as to be in the range halfway between the rear end of 11a. The main clutch lever 9 has a guide groove 11a.
When located at the rear end, the clutch is disengaged. Therefore,
When the main clutch lever 9 is in the front region of the dead point DP, it is maintained at the front end of the guide groove 11a by the toggle mechanism without being manually held, while the main clutch lever 9 is held.
When is in a region behind the dead point DP, the clutch cannot be maintained in the engaged state unless it is manually held.

As shown in FIGS. 1 and 2, a check plate 12 as a check member constituting a check tool 17 is pivotally attached to an operation box A so as to be swingable around a vertical axis P, and a dead point is set. A posture in which one end enters the clutch engagement range between the DP and the rear end of the guide groove 11a to restrict the operation of the main clutch lever 9 toward the front side, and the first restraining portion 12 at that end.
A is retractable from the clutch engagement range and can be switched to a posture in which the restriction is released. The restraint plate 12 is biased by the spring 13 to release the restriction, and the release wire 14 is attached to the shift lever 10.
The release wire 14 is pulled in conjunction with the backward movement operation of the speed change lever 10 so that the check plate 12 is switched to the regulation posture, and is linked to the neutral or forward operation of the speed change lever 10. When the release wire 14 is loosened, the restraint plate 12 is switched to the regulation release posture.

Further, as shown in FIGS. 1 and 2, the main clutch lever 9 has a contact member 15 made of a rod-shaped member.
Are provided so as to extend in the lateral direction. This contact member 15
Is extended laterally beyond the vertical axis P position, and when the check plate 12 is in the restricting posture, the end part of the check plate 12 that contacts the main clutch lever 9 is pressed. The second restraint unit 12 which is the other end portion different from the first restraint unit 12A
A contact portion 15a for contacting B is provided. Then, when the restraint plate 12 is in the regulation release posture, the restraint plate 1 is moved from the path that moves together with the main clutch lever 9 of the contact portion 15a.
The second second restraint unit 12B is also retracted. Therefore,
When the speed change lever 10 is operated in a neutral or forward direction other than reverse, the restraint plate 12 is in the deregulation posture, and the main clutch lever 9 and the abutment portion 15a can be operated to a position where the clutch is held. On the other hand, on the other hand, when the shift lever 10 is being operated in the reverse direction, the check plate 12 is rocked to the restricting posture, so that the main clutch lever 9 and the abutment portion 15a are respectively connected to the first abutment plate 12 of the check plate 12. The check plate 1 is to be brought into contact with the portion 12A and the second contact portion 12B.
Since the two rotating end portions of 2 are pushed in the same direction at the same time, the check plate 12
The rotation of the main clutch lever 9 is suppressed, and consequently the swinging operation of the main clutch lever 9 beyond the dead point DP to the forward slip is disabled.

With the above construction, the driver must hold the main clutch lever 9 so that the clutch disengagement does not return to the back when maintaining the clutch engaged state when the vehicle is moving backward. For this reason, when the driver releases the main clutch lever 9 when there is a dangerous situation such as the driver falling over in reverse, the main clutch lever 9 clutch disengagement automatically returns to the traveling wheels 5. Will stop the transmission of.

The present invention may be implemented as follows. (A) The restraint device that is rockably operated as in the above embodiment is configured so that the restraint of the main clutch lever is limited only by the contact regulation with the main clutch lever main body.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a partially cutaway plan view showing a main clutch lever and a safety mechanism.

FIG. 2 is a vertical sectional rear view showing a main clutch lever and a safety mechanism.

FIG. 3 is a side view showing a walk-behind management machine.

FIG. 4 is a side view showing a conventional main clutch lever.

[Explanation of symbols] 9 Main clutch lever 12 Check members 12A First check unit 12B Second restraint unit 15 Contact member 17 restraints

Claims (2)

[Claims] 1. A clutch operating range of the main clutch lever (9) is a range in which the main clutch lever (9) is held in a clutch engaged state beyond a dead point (DP), and the dead point (DP). The main clutch lever (9) is arranged in a range in which the main clutch lever (9) is urged to return to the clutch disengaged position at the front side, and the main clutch lever (9) is interlocked with the operation of the transmission in the reverse direction. A safety mechanism for a walk-behind work machine provided with a restraining device (17) for restraining an operation into a clutch engagement operation range exceeding the dead point (DP). 2. A contact member (15) is integrally connected to the main clutch lever (9) so as to be integrally movable, and the restraining device (17) has the main clutch lever at one end of the restraining member (12). (1) A first restraining portion (12A) that enters the clutch engagement operating range and contacts the main clutch lever (9) to restrain it, and enters the moving range of the engaging member (15) at the other end. And a second restraint section (12B) for restraining the restraint by contacting the restraining member (15) with the restraint tool (12) around an axial center between the two restraint sections (12A), (12B). The walking mechanism as claimed in claim 1, wherein the safety mechanism is pivotally attached to the shaft.