JP2000020154A - Operation handle structure of working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce fatigue and to improve the operability by providing an operation handle with a throttle lever which controls the rotating speed of an engine and a brake lever controlling the braking state of a working tool, and arranging the throttle lever on the working tool side and the brake lever on the engine side. SOLUTION: The throttle lever 12 is arranged on the bush cutter side of an operation lever device 10 and the brake lever 13 is arranged on the engine side to enable operation for gripping the handle case of the operation lever device 10 on a finger side and operation for operating the throttle lever 12. In this case, the throttle lever 12 is drawn with the finger to obtain an engine rotating speed needed for operation. At this time, the throttle lever 12 is held at its position because of the friction of a friction washer even when the finger is put away from the lever 12 in a stroke of the throttle lever 12. Therefore, the operation is carried out by gripping only the brake lever 13 after the rotating speed of the engine is adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an operating handle structure for a working machine.

[0002]

2. Description of the Related Art As an operation handle structure of a working machine, for example, Japanese Patent Publication No. 57-21962, "Safety Device in a Cutting Work Machine" and Japanese Utility Model Publication No. 57-42261, "Cutter Brake Device in a Cutting Machine" are known. ing.

[0003] In the above, the brake lever can be quickly and accurately operated in the direction of operating the brake, and the throttle lever can be quickly and accurately operated in the direction of closing the throttle valve.
In addition to ensuring safety during emergencies during work, the brakes can be maintained in the operating state when throttle operation is performed during non-work such as engine start and adjustment. As shown in FIG.
A throttle lever 3 and a brake lever 4 are provided on the same side of the operation handle 1 so as to be swingable so that the tips overlap when gripped. Brake lever 4
Is to release the operation of the brake by grasping.

The above relates to a mechanism for operating the brake by releasing the grip of the lever and releasing the hand from the handle. As shown in FIG. 3 of the publication, the handle grip 2 of the handle 1 is used. And a arm 10 connected to the brake wire 4 and attached to the handle 1 so as to be rotatable around the handle 1 in order to control the operation of the brake.

[0005]

In the above, since the throttle lever 3 and the brake lever 4 are located on the same side of the handle 1, the worker's finger, for example, the middle finger,
The load applied to the handle 1 is supported by the ring finger and the little finger, and the brake lever 4 is pressed, and the throttle lever 3 is operated by another finger, for example, the forefinger. There is an inconvenience that it becomes easier to do so.

[0006] In the above description, the arm 10 is
Is rotated to stop at a predetermined position and grip the handle grip portion 2. For example, in order to operate the throttle lever 9 with the index finger, forces in different directions such as gripping the handle 1 and holding the rotational force around the handle 1 are generated. Required, hands,
In particular, since the wrist keeps the arm 10, the tire tends to be fatigued, which may make it difficult to operate and maintain the posture of the working machine in a continuous operation, or may adversely affect the finished state of the operation. Therefore, an object of the present invention is to provide an operation handle structure of a working machine in which the operability of the operation handle is improved to reduce fatigue and improve operability.

[0007]

In order to achieve the above object, a first aspect of the present invention relates to a working machine in which a work implement is driven by an engine and an operation handle is disposed between the work implement and the engine. A throttle lever for controlling the rotation speed of the engine and a brake lever for controlling the braking state of the work implement are provided on the steering wheel, the throttle lever is arranged on the work implement side, and the brake lever is arranged on the engine side. The operation of gripping the operation handle and the operation of the throttle lever on the finger side are performed, and the operation of gripping the operation handle and the operation of the brake lever on the palm side are performed simultaneously and in one operation, so that the burden on the finger side is light. Become.

According to a second aspect of the present invention, a handle case, a throttle lever movably attached to the handle case for pulling a throttle wire, and a built-in handle case for attaching a predetermined resistance to the throttle lever to increase the movement. And a brake lever movably mounted on the handle case to control the throttle restraint mechanism and pull the brake wire. By holding the brake lever, the throttle restraining mechanism is controlled to hold the throttle lever at an arbitrary position.

According to a third aspect of the present invention, the throttle lever is provided with a throttle return lever for pushing back the throttle to the closing side. When finely adjusting the throttle, that is, when the throttle lever is returned to slightly move the throttle to the closing side, the throttle lever is pushed back by the throttle return lever.

According to a fourth aspect of the present invention, the throttle restraining mechanism has a throttle lever stopper which can restrict the movement of the throttle lever in order to maintain the idling state when the engine is started and can release the restriction of the movement of the throttle lever when the brake lever moves. Provided.

[0011] It is possible to eliminate the need for the operator to start the engine while operating the throttle, thereby simplifying the handling of the working machine. Also, when the engine is idling, the throttle lever stopper is disengaged from the throttle lever by moving the brake lever and the throttle can be opened as needed from the idling state, so work can be started smoothly. it can.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings should be viewed in the direction of reference numerals. FIG. 1 is a side view showing a state in use of a working machine employing an operation handle structure according to the present invention. An operator M hangs a brush cutter 1 as a working machine from a shoulder with a hanging belt 2, and shows the present invention. 1 shows a state in which a mowing operation is performed by grasping the operation lever device 10 employing the operation handle structure of FIG.

The brush cutter 1 includes an engine 3, a cutter 4 as a working tool driven by the engine 3, and an engine 3
An operating rod 5 is provided between the operating rod 5 and the cutter 4, a handlebar 6 attached to the operating rod 5, a grip 7 attached to the handlebar 6, and an operating lever device 10 as an operating handle.

FIG. 2 is a perspective view of the operation lever device according to the present invention.
And the engine 3 (see FIG. 1)
A throttle lever 12 attached to be able to swing to control the rotation speed of the cutter, a brake lever 13 also attached to the handle case 11 to be able to swing to control the braking state of the cutter 4 (see FIG. 1), and a throttle lever A throttle return lever 14 is provided for pushing the throttle 12 back to the side to close the throttle, and a kill switch 15 for stopping the engine 3 is provided. The handle case 11 includes an upper case 18 including left and right cases 16 and 17 and a lower case 19 also serving as a grip.

FIG. 3 is a longitudinal sectional view of the operating lever device according to the present invention. The operating lever device 10 includes a throttle wire 22 connected to an end of a throttle lever 12 and a brake connected to an end of a brake lever 13. A wire 23;
A cam member 24 is provided between the throttle lever 12 and the brake lever 13.

The throttle lever 12 is connected to the upper case 1
8, a cylindrical portion 12a rotatably attached to a first shaft portion 18a, and a lever portion 1 extending from the cylindrical portion 12a.
2b, a substantially fan-shaped plate portion 12c, an arc-shaped long hole 12d formed in the plate portion 12c, and a throttle return lever 14
It comprises a screw portion 12e to which a nut is welded to fix (see FIG. 2) with a screw, and a contact surface 12f formed on a lever portion 12b to contact the cam member 24.

The brake lever 13 includes an upper case 18
A cylindrical portion 13a rotatably attached to a second shaft portion 18b formed on the second shaft portion 18b, and a lever portion 13 extending from the cylindrical portion 13a.
b and the arm 13c. Throttle wire 2
2 and the brake wire 23 are connected to the engine 3 (see FIG. 1).
It is drawn from the side and passed through the handlebar 6 from the middle. The cam member 24 includes a throttle lever stopper 24a that restricts a swing to a side where the throttle is opened by being brought into contact with a contact surface 12f of the throttle lever 12.

Here, reference numeral 18c denotes an upper case 18 for regulating the counterclockwise swing of the brake lever 13.
A spring stop provided on the left case 16; 25, a spring for applying a swing force to the throttle lever 12 in the direction of rotation of the throttle to the closing side; and 26, a brake lever 13 for releasing the brake operation. It is a spring that gives a swing force in the direction to be made.

FIG. 4 is a cross-sectional view of the operation lever device according to the present invention. The operation lever device 10 is provided with the plate-like portion 12 of the throttle lever 12
friction washer 2 arranged so as to sandwich c
7, 28 and disc springs 31 and 32, and these cam members 2
4. Friction washers 27, 28 and disc spring 31,
A screw member 17a and a hexagon socket head cap screw 34 fixed to the right case 17 with a cap nut 33 are provided to penetrate the right case 17 and provide the right case 17 with the screw member 17a. 35, 36, 37
Is a washer, and 38 and 38 are case mounting bolts.

The slot lever 12 has a throttle wire mounting portion 12g at the end of the plate-like portion 12c.
(See FIG. 3). The brake lever 13 has a brake wire mounting portion 13d and a cylindrical portion 13e at the end of the arm portion 13c, and the brake wire 2 is mounted on the brake wire mounting portion 13d.
3 (see FIG. 3). The right case 17 includes a cam portion 17b that contacts the cam member 24. The cam member 24 has an elongated hole 24c for connecting to the arm portion 24b and the cylindrical portion 13e of the brake lever 13.

The friction washers 27 and 28 generate frictional force when pressed against the plate portion 12c of the throttle lever 12, and are preferably made of rubber. Disc springs 31 and 32 are friction washers 2
This is for obtaining a load for pressing 7, 28.

The hexagon socket head cap screw 34 changes the role of the cam member 24 and the amount of deflection when the disc springs 31 and 32 are attached to change the load generated on the disc springs 31 and 32, and It also serves as a pressing load adjusting member that changes the load when pressing the friction washers 27 and 28 against the plate-like portion 12c.

That is, when the hexagon socket head bolt 34 is, for example, a right-handed screw, by turning it clockwise, the conical springs 31 and 32 are largely bent by the head 34a of the hexagon socket head bolt 34 to increase the pressing load. By turning to the left, the disc springs 31,3
(2) to reduce the pressing load. The same applies to left-handed screws.

The arm 1 of the above-mentioned brake lever 13
3c and the cylindrical portion 13e, the cam member 24, the cam portion 17b of the handle case 11, and the friction washer 2
7, 28, disc springs 31, 32, hexagon socket head bolt 3
4 together with the throttle restraining mechanism 39.

FIG. 5 is a perspective view showing the cam member and the cam portion of the handle case according to the present invention.
The cam portion 17b of FIG. 1 (see FIG. 2) is provided with cam ridges 17d on the cam surface 17c. The cam member 24 includes a cam surface 24e facing the cam surface 17c of the cam portion 17b at the bottom of the concave portion 24d.
4e is provided with a cam groove 24f in which the cam ridges 17d of the cam portion 17b engage and a flat surface 24g.

FIGS. 6A and 6B are explanatory views for explaining the cam portion of the handle case according to the present invention. FIG. 6A is a sectional view taken along the line 6-6 in FIG. 5, and FIG. It is. In (a), the cam ridge 17d of the cam portion 17b has a slope 17e.
And a flat top surface 17f and a vertical surface 17g.
The height h of each of the cam peaks 17d is equal. In (b), the angle of the slope 17e of the cam tip 17d is m, and the slope 17e
When the angle of the sum of the peaks 17f and n is n, and the pitch angle between the cams 17d is p, the angle m,
n is also equal.

FIGS. 7A and 7B are explanatory views for explaining a cam member according to the present invention. FIG. 7A is a sectional view taken along line 7-7 in FIG. 5, and FIG. 7B is a front view. In (a), the cam groove 24f of the cam member 24 includes a slope 24h, a flat groove bottom 24j, and a vertical surface 24k. Which cam groove 24f
Are also equal.

In (b), the slope 24 of the cam groove 24f
The angle h is m, the pitch angle between the cam grooves 24f is p,
The angles m of all the cam grooves 24f are equal. Also, the slope 24
Assuming that the angle obtained by combining h and the groove bottom surface 24j is r, the relationship between the angle n and the angle n shown in FIG. 6B is r ≧ n.

The above-described cam portion 17b and cam member 2
The operation of No. 4 will now be described. FIGS. 8A to 8D are operation diagrams illustrating the operation of the cam portion and the cam member according to the present invention. In (a), first, the cam ridge 1 of the cam portion 17b
7d and the cam groove 24f of the cam member 24 are engaged. In (b), the cam member 24 starts rotating, the cam groove 24f moves downward in the figure, and the slope 17 of the cam portion 17b is moved.
e and the slope 24h of the cam member 24 are in contact with each other.

In (c), the slope 24h is the slope 17
Start climbing e. As a result, the cam member 24 gradually moves away from the cam portion 17b, and the amount of movement of the cam member 24 in the axial direction (the left-right direction in the drawing) with respect to the cam portion 17b at this time is s1.
Becomes In (d), the slope 24h further becomes the slope 17
Then, the flat surface 24g of the cam member 24 moves while contacting the top surface 17f of the cam portion 17b. At this time, the amount of movement of the cam member 24 in the axial direction (the left-right direction in the drawing) with respect to the cam portion 17b is s2, that is, the height h of the cam peak 17d.

As described above, the cam 17d is formed on the slope 17e.
The cam member 24 moves in the axial direction until the cam member 24 rotates to a predetermined angle by providing the slope 24h and the groove bottom surface 24j in the mountain top surface 17f and the cam groove 24f. Stop moving in the direction.

FIG. 9 is a sectional view taken along the line 9-9 in FIG. 1, and shows the braking device 40 provided in front of the engine 3 (see FIG. 1) in a braking state. The brake device 40 is provided between the engine 3 and the cutter 4 (see FIG. 1), and a drum 41 which is a clutch drum on the side of the cutter 4 of a centrifugal clutch (not shown) that interrupts power. A brake shoe 42 for stopping rotation of the cutter 4 by circumscribing the drum 41, a brake arm 43 for moving the brake shoe 42, a brake wire 23 connected to an end of the brake arm 43, and a brake for the drum 41 It comprises a tension coil spring 44 for generating a load for pressing the shoe 42 and the brake lever 13 (see FIG. 3). 1a is a clutch case.

The brake arm 43 is swingably mounted on a brake arm shaft 45 mounted on the housing 1a. A first arm 43a to which the brake wire 23 is connected and a second arm portion to which the brake shoe 42 is mounted. 43b and a third arm 43c to which a tension coil spring 44 is attached. Here, 1b is a spring hook portion, 1c is a brake wire support portion, and 23b is a wire tip stopper of the brake wire 23.

The operation of the operation lever device 10 described above will now be described. First, in FIG.
The engine 3 (see FIG. 1) is started without grasping the engine 3. At this time, since the throttle lever 12 is regulated by the cam member 24 to the position where the throttle is most closed, the engine 3 is in an idling state. FIG.
Since the brake device 40 is in a braking state in which the brake shoe 42 is pressing the drum 41, the cutter 4 (see FIG. 1) does not operate even when the engine 3 starts.

FIGS. 10A and 10B are operation diagrams (first operation diagrams) for explaining the operation of the operation lever device according to the present invention, wherein FIG. 10A is a longitudinal sectional view, and FIG. The figure is shown.
In (a), to start the work, first, the brake lever 13 is received and squeezed with the flat side of the hand H. By gripping the brake lever 13, the arm 13 c of the brake lever 13 swings clockwise around the second shaft 18 b, and the arm 13 pulls the brake wire 23.

At this time, since the cylindrical portion 13e of the arm portion 13c shown in FIG. 4 is in a state of being inserted into the elongated hole 24c opened in the arm portion 24b of the cam member 24, the arm portion shown in FIG. With the swing of 13c, the cam member 24
Rotates counterclockwise around the hexagon socket head bolt 34 serving as a shaft, the throttle lever stopper 24a of the cam member 24 comes off the contact surface 12f of the throttle lever 12, and releases the position restriction of the throttle lever 12. . Therefore, the throttle lever 12 can swing.

In FIG. 10B, when the cam member 24 rotates, the cam member 24 moves in the axial direction with respect to the cam portion 17b as described with reference to FIG. 8, so that the disc spring 31 shown in FIG. , 32 are bent to be substantially flat, and a large load is generated to press the plate-like portion 12c of the throttle lever 12 with the friction washers 27, 28. Therefore, a gap between the plate-like portion 12c and the friction washers 27, 28 is formed. A large frictional force is generated to restrain the throttle lever 12 from swinging.

At this time, the brake lever 13 (FIG. 10)
(A) is in the most swung state, and the cam portion 1
7b and the cam member 24 have the positional relationship shown in FIG. That is, the flat surface 24g of the cam member 24 is in contact with the peak surface 17f of the cam portion 17b.

Therefore, immediately before the brake lever 13 swings most, the cam member 24 does not move in the axial direction with respect to the cam portion 17b, so that the frictional force between the plate portion 12c and the friction washers 27, 28 is large. The restraining force for restraining the swing of the throttle lever 12 becomes constant.

Therefore, for example, even if the brake lever 13 slightly moves during the work, the operating force for operating the throttle lever 12 changes, or the finger F (see FIG. 10A) separates from the throttle lever 12. In this case, the throttle lever 12 does not return to the side that closes the throttle.

If the operation force of the throttle lever 12 is too large, turning the hexagon socket head bolt 34 to reduce the deflection of the disc springs 31 and 32 will reduce the friction between the plate-like portion 12c and the friction washers 27 and 28. The frictional force between them is reduced, and the operation force can be reduced.

FIG. 11 is an operation diagram (second operation diagram) for explaining the operation of the brake device connected to the operation lever device according to the present invention. The brake lever 13 shown in FIG.
When the arm portion 13c of FIG.
The brake arm 43 shown in FIG.
The brake shoe 42 swings clockwise around the brake arm shaft 45 against the pulling force of 4, and the brake shoe 42 separates from the drum 41 to release the braking. Therefore, the cutter 4 (see FIG. 1) becomes operable.

12 (a) and 12 (b) are action diagrams (third action diagrams) for explaining the operation of the operation lever device according to the present invention, where (a) is a longitudinal sectional view and (b) is a side view. Is shown. (A)
, The throttle lever 12 is pulled with the finger F to set the rotation speed of the engine 3 (see FIG. 1) necessary for the work. At this time, since the throttle lever 12 is restrained by the friction washers 27 and 28 (see FIG. 10B), the position is maintained even when the finger F is released from the throttle lever 12 during the stroke of the throttle lever 12. be able to. Therefore, after adjusting the rotation speed of the engine 3, the work may be performed while holding only the brake lever 13. In (b), when the rotational speed of the engine 3 (see FIG. 1) is reduced during the operation, the finger F is released from the lever portion 12b of the throttle lever 12, and the throttle return lever 14 is pushed back with the thumb T.

As described above, the operation lever device 10
By disposing the throttle lever 12 on the side of the brush cutter 1 (see FIG. 1) and the brake lever 13 on the side of the engine 3, the handle case 1 of the operating lever device 10 can be moved with the finger F side.
1 (see FIG. 2) and the operation of operating the throttle lever 12 can be performed, and the operation of gripping the handle case 11 and the operation of the brake lever 13 on the palm side are performed simultaneously and in one operation. Finger F
There is no need to operate both levers 12 and 13 on the side, the load on the finger F is reduced, and the worker M can operate even for a long time.
The fatigue of the hand H (see FIG. 1) can be reduced, and the operation lever device 10 can be securely held. Also,
It is possible to easily change and hold the position of the brush cutter 1 and to improve the operability and workability of the brush cutter 1.

By holding the brake lever 13,
The throttle lever 12 can be held at an arbitrary position by controlling the throttle restraining mechanism 39 (see FIG. 4), and fine adjustment of the throttle can be easily performed. Therefore, the work can be performed while the handle case 11 and the brake lever 13 are grasped without grasping the throttle lever 12, and the operability and workability of the brush cutter 1 can be improved.

Further, by providing the throttle return lever 14, fine adjustment of the throttle, that is, the throttle lever 1
It becomes easier to perform the operation of returning the throttle 2 and slightly moving the throttle to the closing side. Therefore, the operability and workability of the brush cutter 1 can be improved.

Furthermore, since the throttle restraining mechanism 39 is provided with the throttle lever stopper 24a (see FIG. 10A), the labor for the operator M to start the engine 1 while performing the throttle operation can be omitted. Brush cutter 1
Can be easily handled. Further, the engine can be brought into an idling state at the time of starting the engine. From this state, if the brake lever 13 is depressed, the throttle lever stopper 24a is released from the throttle lever 12, and the throttle can be opened from the idling state as required. Can be started smoothly.

The throttle restraining mechanism 39 (see FIG. 4) of the present invention is provided with the cam ridge 17d of the cam portion 17b and the cam groove 24f of the cam member 24 shown in FIG. May be provided with a cam ridge, and the other may be a simple convex portion having no cam shape, such as a cam ridge or a cam groove.

[0049]

According to the present invention, the following effects are exhibited by the above configuration. In the operation handle structure for a working machine according to claim 1, since the throttle lever is arranged on the work implement side of the operation handle and the brake lever is arranged on the engine side, the operation of gripping the operation handle with the finger side and the operation of operating the throttle lever are performed. The operation of gripping the operation handle and the operation of the brake lever on the palm side can be performed simultaneously and in one operation, so that the burden on the finger side is reduced, and the operator can work for a long time. The fatigue of the hand can be reduced, and the operation handle can be securely held. Also, the posture of the working machine can be easily changed and held, and the operability of the working machine,
Workability can be improved.

The operation handle structure of the working machine according to claim 2 is
The handle case is equipped with a throttle restraint mechanism that increases the movement of the throttle lever in conjunction with the operation of the brake lever, so by holding the brake lever, the throttle restraint mechanism is controlled and the throttle lever is held at an arbitrary position. And fine adjustment of the throttle can be easily performed. Therefore, without holding the throttle lever,
Work can be performed in a state where the handle case and the brake lever are gripped (for example, a state in which the brake is released by the brake lever), and the operability and workability of the work machine can be improved.

The operation handle structure of the working machine according to claim 3 is
Since the throttle lever is provided with the throttle return lever, fine adjustment of the throttle, that is, the operation of returning the throttle lever and slightly moving the throttle to the closing side is further facilitated. Therefore, the operability and workability of the working machine can be improved.

The operation handle structure of the working machine according to claim 4 is
Since the throttle restraining mechanism is provided with the throttle lever stopper, it is not necessary for the operator to start the engine while performing the throttle operation, and the workability of the working machine can be simplified.

When the engine is started, the engine can be brought into an idling state. From this state, if the brake lever is moved,
Since the throttle lever stopper can be removed from the throttle lever and the throttle can be opened as needed from the idling state, the operation can be started smoothly.

[Brief description of the drawings]

FIG. 1 is a side view showing a state in use of a working machine employing an operation handle structure according to the present invention.

FIG. 2 is a perspective view of an operation lever device according to the present invention.

FIG. 3 is a longitudinal sectional view of the operation lever device according to the present invention.

FIG. 4 is a cross-sectional view of the operation lever device according to the present invention.

FIG. 5 is a perspective view showing a cam member and a cam portion of a handle case according to the present invention.

FIG. 6 is an explanatory view illustrating a cam portion of the handle case according to the present invention.

FIG. 7 is an explanatory view illustrating a cam member according to the present invention.

FIG. 8 is an operation diagram illustrating the operation of the cam portion and the cam member according to the present invention.

FIG. 9 is a sectional view taken along line 9-9 of FIG. 1;

FIG. 10 is an operation diagram (first operation diagram) for explaining the operation of the operation lever device according to the present invention.

FIG. 11 is an operation diagram (second operation diagram) for explaining the operation of the brake device connected to the operation lever device according to the present invention.

FIG. 12 is an operation diagram (third operation diagram) illustrating the operation of the operation lever device according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Work machine (claw cutter), 3 ... Engine, 4 ... Work implement (cutter), 6 ... Handle bar, 10 ... Operation handle (Operation lever device), 11 ... Handle case, 12 ... Throttle lever, 13 ... Brake lever , 14: throttle return lever, 23: brake wire, 39: throttle restraining mechanism.

Continuing from the front page (72) Inventor Takashi Ikeda 1-4-1, Chuo, Wako-shi, Saitama Pref. Inside of Honda R & D Co., Ltd. (72) Inventor Jun Kojima 1-4-1, Chuo, Wako-shi, Saitama Co., Ltd. Honda R & D F-term (reference) 2B083 AA02 BA02 DA02 HA22 HA23 HA24 3G065 BA04 CA22 GA46 JA02 JA11 KA05 3J070 AA03 BA11 BA32 CA43 DA24

Claims (4)

[Claims] 1. A work implement in which a work implement is driven by an engine and an operation handle is disposed between the work implement and the engine, wherein the operation handle controls a rotation speed of the engine, and a braking state of the work implement. And a brake lever for controlling the operation of the work implement, wherein the throttle lever is arranged on the work implement side, and the brake lever is arranged on the engine side. 2. A handle case, a throttle lever movably attached to the handle case for pulling a throttle wire, and a throttle restraint built in the handle case for attaching a predetermined resistance to the throttle lever to increase the movement. An operating handle structure for a working machine comprising a mechanism and a brake lever movably mounted on a handle case for controlling the throttle restraining mechanism and pulling a brake wire. 3. The operation handle structure for a working machine according to claim 1, wherein the throttle lever is provided with a throttle return lever for pushing back the throttle to a closing side. 4. The throttle restraining mechanism is provided with a throttle lever stopper for restricting the movement of the throttle lever in order to maintain an idling state when the engine is started and releasing the restriction of the movement of the throttle lever when the brake lever is moved. 3. The method according to claim 2, wherein
The operating handle structure of the described working machine.