JPH0511706Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has a first operating shaft for forward gear shifting and a second operating shaft for reverse gear shifting protruding from the side surface of the upper part of the transmission case, and The present invention also relates to a high-speed backward movement restraining mechanism for a walk-behind work machine, in which a speed change lever for changing speed by inserting and removing a second operation shaft, and a control handle are supported so as to be changeable forward and backward.

[Conventional technology]

In walk-behind tillers, etc., in order to prevent dangerous conditions such as backward movement toward the operator at high speed, the operation axis on the backward movement side of the first and second operation axes must be operated to the high speed side. Some models are equipped with a restraining member to prevent this, but as mentioned above, in the case where the control handle can change the direction forward and backward, for example,
As disclosed in Publication No. 51134, the first and second operating shafts are set to be shifted to the high speed side by pushing them into the inside of the transmission case, and the ends of the operating shafts and the transmission are Some devices have a structure in which a check member is inserted between the case side wall and the operation shaft to prevent the operation shaft from moving toward the high-speed side.

[Problem that the invention attempts to solve]

With the above structure, the restraining member can be moved and operated within the narrow space between the end of the first operating shaft and the side wall of the mission case, and between the end of the second operating shaft and the side wall of the mission case. Therefore, it is necessary to extend a manual operation member for a relatively long distance outward from this check member.
The structure of the manual operation system for the check member has tended to become more complicated.

The present invention focuses on the above-mentioned problem and aims to simplify the manual operation system of the check member as much as possible.

[Means for solving problems]

The present invention consists in configuring the high-speed backward movement restraining mechanism of the above-mentioned walk-behind work machine as follows. In other words,
The direction in which the first and second operation shafts are pulled out from the mission case is set to the high speed side, and the first and second operation shafts are
an elongated hole that guides a restraining member that contacts and prevents operation of one of the operating shafts to the high-speed side between a restraining position relative to the first operating shaft and a restraining position relative to the second operating shaft, so as to be movable and operable; An information board with
Further, a screw member is provided for tightening and fixing the check member to the guide plate, and a side wall portion along the movement operation direction of the check member is bent at the outer end of the guide plate, and the check member is provided on the inner surface of the side wall portion. The restraining member is formed so as to maintain the working posture of the restraining member by abutting a part of the member, and its functions and effects are as follows.

[Effect]

As mentioned above, when the gears are shifted to the high speed side by pulling the first and second operating shafts outward from the transmission case, the check member is placed outside the operating shafts where there is sufficient space. If you do this, you can do it without having to extend the operating member for a long time from the check member.
This makes it possible to operate the check member almost directly. Furthermore, by attaching a check member to the elongated hole of the guide plate, which is a plate material, there is a risk that the check member will also rotate when the screw member is rotated. By abutting a portion of the restraining member, this side wall portion serves as a guide for the restraining member, and the co-rotation phenomenon of the restraining member is prevented.

[Effect of idea]

As described above, a structure that can prevent changes in posture while supporting and guiding the restraining member can be obtained by simply drilling a long hole in the board and bending the outer edge, and the restraining member can also be made using a small screw member. Direct manual operation is now possible, and the check member can be operated without any trouble without using a relatively long operating member as in the conventional structure, and manufacturing costs can be reduced.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS A walk-behind work machine that is an embodiment of the present invention will be described below based on the drawings.

As shown in Fig. 4, the lower left and right parts of the transmission case 1 are equipped with a main transmission capable of shifting into two forward speeds and two reverse speeds, and an auxiliary transmission capable of shifting into two high and low speeds (not shown). In addition to being equipped with wheels 2a and 2b, an engine 3 is provided at the front of the mission case 1, a control handle 4 is provided at the top of the mission case 1, and various work devices such as a rotary tiller are mounted on brackets 5 at the front and rear of the mission case 1. can be freely connected to form a walking-type agricultural work machine.

As shown in FIGS. 1, 3, and 4, the operating handle 4 is rotatable around a vertical axis _P1 at the top of the mission case 1, and is configured to be able to change its direction back and forth. The power from the engine 3 is input to the input shaft (not shown) of the transmission case 1 via a belt transmission mechanism (not shown) inside the belt case 15. The space between the housing and the housing case 1 is covered with a cover 13, and each mechanism is disposed within this cover 13.

More specifically, first and second operating shafts 8 and 7 for the main transmission protrude from the side surface of the transmission case 1, and these first and second operating shafts 8 and 7 can be inserted and removed in the axial direction. In this way, it is possible to change the speed in two steps in the direction of movement on the operating shaft side. (When the operating shaft is pushed into the mission case 1, it becomes the low-speed side, and when pulled out from the mission case 1, it becomes the high-speed side.) Near the first and second operating shafts 8 and 7, there is a first boss member. 9 is the horizontal axis P ₃ of the transmission case 1
A second boss member 10 is rotatably supported around the first boss member 9, and a second boss member 10 is rotatably fitted to the first boss member 9.

The operating arm 11 extends from the second boss member 10 and is engaged with one of the first and second engaging portions 8a and 7a provided on the first and second operating shafts 8 and 7, and A main shift lever 6 is engaged with a spline portion on the inner surface of the two-boss member 10, and extends through an insertion hole 16 on the upper surface of the cover 13. In the state shown in FIG. 1, by swinging the main shift lever 6 around the vertical axis _P2 of the second boss member 10, the second operating shaft 7 is inserted or removed, and the machine moves to the right , and it becomes possible to shift between two stages, high and low.

Next, when the main shift lever 6 is returned to the neutral position and swung upward, the operating arm 11 is moved to the first engaging portion 8.
Involve a. As a result, the first operating shaft 8 becomes operable, and the aircraft moves to the left when viewed from the drawing page, allowing for two-stage speed changes. Then, by lifting the main shift lever 6 upward and removing the spline fitting, the main shift lever 6 can be rotated 180° around the vertical axis _P2 .
It can be rotated, and the direction of the main shift lever 6 can be changed back and forth.

Next, to explain in detail the restraining structure for the first and second operating shafts 8 and 7, as shown in FIGS. 1 and 2, a guide plate 17 for a restraining member 12, which will be described later, is attached to the inner surface of the cover 13. The cover 13 and the guide plate 17 are connected to the first and second operating shafts 8 and 7.
A long hole 17a extending between both operating shafts 8 and 7 is formed on the outside of the shaft, and a restraining member 12 having an inverted L-shape when viewed from the front is slidably operated along this long hole 17a. It is attached by a knob 14 having a section 14a. The end side of the guide plate 17 is bent downward to form a side wall portion 17b, and the check member 1 is attached to the inner surface of the side wall portion 17b.
The end side of the knob 2 is pressed from the inside, so that even if the knob 14 is held by hand and slid along the elongated hole 17a or rotated, the check member 12 does not rotate. I try not to.

The state shown in FIGS. 1 and 2 is the operating handle 4.
The main shift lever 6 is extended rearward, which is the normal position, and the operating arm 11 is engaged with the second operating shaft 7, so that the gear can be shifted to the reverse side. The tip of the second operating shaft 7 enters the high-speed side position, and the operation of the main shift lever 6 toward the high-speed reverse side, that is, the operation of pulling the second operating shaft 7 outward from the transmission case 1, is performed by the restraining member 12. This is prevented by the contact between the second operating shaft 7 and the second operating shaft 7.

Next, when the control handle 4 and the main shift lever 6 are facing forward as shown in FIG.
4 by hand and slide the check member 12 to the position shown in the figure, the tip of the check member 12 will enter the high speed side position of the first operation shaft 8. As a result, in the state shown in the figure, the operation of the main shift lever 6 toward the high-speed reverse side, that is, the operation of pulling the first operating shaft 8 outward from the transmission case 1, is performed by the check member 12 and the first operating shaft 8. This is prevented by contact.

[Another example]

In the embodiment described above, the separate guide plate 17 is used as the cover 1.
3, but the guide plate 17 is omitted by giving the cover 13 the function of the guide plate 17, and the edge of the cover 13 is bent downward to form a side wall, and a restraining member is attached to this side wall. A structure in which a part of 12 is applied can also be adopted.

Note that although reference numerals are written in the claims section of the utility model registration for convenience of comparison with the drawings, the present invention is not limited to the structure of the attached drawings by such entry.

[Brief explanation of the drawing]

The drawings show an embodiment of the high-speed reverse check mechanism for a walk-behind work machine according to the present invention. 2 is a side view of the vicinity of the operating shaft showing a state in which the operation that would proceed is blocked, FIG. 2 is a rear view of the restraining member and the vicinity of the operating shaft in the state shown in FIG. 1, and FIG. Figure 4 is a side view of the vicinity of the operating axis, showing a state in which when the main gear shift lever is directed toward the front of the aircraft, the operating handle is prevented from moving at high speed in the direction in which it is extended. FIG. 2 is an overall side view of the mold working machine. 1...Mission case, 4...Control handle, 6...Speed lever, 7...Second operation shaft, 8...
...First operating shaft, 12... Checking member, 17... Guide plate, 17a... Elongated hole, 17b... Side wall portion.

Claims (1)

[Scope of utility model registration request] A first operating shaft 8 for forward gear shifting and a second operating shaft 7 for reverse gear shifting protrude from the side surface of the upper part of the transmission case 1, and the first and second operating shafts 8,
A high-speed backward movement check mechanism for a walk-behind work machine, in which a gear shift lever 6 for operating a gear change by inserting and removing a gear lever 7, and a control handle 4 are supported so as to be freely changeable in the forward and backward directions. A restraining member 12 is provided to set the direction in which the is pulled outward from the transmission case 1 to the high-speed side, and to contact and prevent one of the operating shafts of the first and second operating shafts 8 and 7 from being operated toward the high-speed side. , a guide plate 17 is provided with a long hole 17a that guides the first operation shaft 8 to a check position and a check position to the second operation shaft 7 in a freely movable manner; The guide plate 17 is provided with a screw member 14 that is tightened and fixed, and a side wall portion 17b is bent on the outer end side of the guide plate 17 along the movement direction of the check member 12, and a part of the check member 12 is formed on the inner surface of the side wall portion 17b. and check member 1.
2. A high-speed backward movement check mechanism for a walk-behind work machine, in which a check member 12 is formed so as to maintain the operating posture of 2.