JP2002316628A - Brake device for work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brake device for a work vehicle capable of installing an intermediate operating unit 4 or the like of an automatic brake device 5 compactly settled in a machine body and adequately switching an ordinary brake operating condition and an automatic brake operating condition. SOLUTION: This brake device for a work vehicle constitutes an automatic brake device 5 of the work vehicle, provided with the automatic brake device 5 automatically operating a rear wheel brake 3a on the machine body turning side according to right/left brake pedals 3R, 3L and handle operation, by an operating wire 30 connecting one end to a front wheel steering device 2a connected to a handle 2 and an intermediate operating unit 4 for changing the operational direction positioned behind a pedal shaft 3 operating the rear wheel brake 3a through a brake rod 31 to connect the other end of the operating wire 30 associated with the pedal shaft 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a braking device for a working vehicle such as a tractor.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Patent No. 3090858, a tractor as a working vehicle is operated by independently depressing left and right rear wheel brakes by depressing a pair of left and right brake pedals and simultaneously operating front wheels. Equipped with an automatic braking device that automatically activates the rear wheel brakes on the turning side of the aircraft in response to the steering wheel operation. Either a normal braking operation state in which braking operation is performed independently or an automatic braking operation state in which steering operation braking is performed It has already been proposed to perform the traveling work by switching over.

[0003]

The tractor having the structure disclosed in the above publication discloses an operating mechanism (intermediate operating body) for operating a brake pedal based on a steering operation to brake a rear wheel brake, an automatic braking operation state and normal braking. Since the switching mechanism (linkage canceling mechanism) for switching between the operating state and the like is all connected by a link rod or a rod,
It occupies a large space in the vertical direction.

[0004] Therefore, for example, in the case of a small-sized tractor or the like which is small and requires a low ground level, there is a disadvantage that the above-mentioned various mechanisms cannot be installed compactly on the abdomen.

[0005] Further, since the operation of the switching mechanism is constituted by a mechanism operated by a handle from the front through a rod member, the installation position of the conversion mechanism for converting and transmitting the operating force is limited.

Also, there are restrictions such as the necessity of specially attaching a buffer required in the braking device at the time of operating the steering wheel, which complicates the structure and increases the cost. There is a problem that it is difficult to install them collectively on the side.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a braking device according to a working device of the present invention is configured to automatically operate a left and right brake pedals 3L and 3R and a rear wheel brake 3a on a turning side of an aircraft in response to a steering operation. Automatic braking device 5 that operates automatically
The automatic braking device 5 includes an operating wire 30 having one end connected to a front wheel steering device 2a linked to the steering wheel 2, and a pedal shaft 3 for operating a rear wheel brake 3a via a brake rod 31. And an intermediate operating body 4 for changing the operating direction, which is connected to the other end of the operation wire 30 and the pedal shaft 3 in an interlocking manner.

[0008] The intermediate operating member 4 is provided with a linkage release mechanism 6 of an automatic braking device 5 which is detachable from the other end of the operation wire 30.
It has.

Further, the intermediate operating body 4 and the pedal shaft 3 are connected so as to be interlocked with each other via a buffer 40 for the rear wheel brake 3a.

The other end of the shock absorber 40, one end of which is connected to the intermediate operating body 4, is connected to an engaging body 41 which is fitted on the pedal shaft 3, and this engaging body 41 is turned by the operation of the handle. The pedal shaft 3 is engaged with the pedal shaft 3 so that the pedal shaft 3 is operated in the brake operation direction by a dynamic operation.
The engagement is released by the independent rotation of the pedal shaft 3 by the operation of the brake pedal.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a working vehicle manufacturing apparatus according to the present invention will be described with reference to the drawings. (Overall Configuration) In FIG. 1, reference numeral 1 denotes a body of a tractor as a working vehicle, and an engine 1a and a transmission 1b are integrally connected by an intermediate case 1c, and a handle provided on an upper front side of the intermediate case 1c. 2 and a steering mechanism having a known configuration (not shown), the left and right front wheels are steered, and the left and right front wheels are provided on the right side of a pedal shaft 3 which is laterally penetrated through the lower abdomen of the intermediate case 1c. By operating the brakes 3L and 3R (FIG. 2), the left and right rear wheel brakes 3a formed in the transmission 1b can be independently braked.

As shown in FIG. 2, the operation of the tractor is performed by turning on / off the power of the engine 1a by depressing the clutch pedal 3b loosely supported on the left base of the pedal shaft 3. I have to.

The tractor 1 is mounted on a main speed change lever (not shown) and the transmission 1b and is operated to rotate forward from a neutral position N to a low speed position L and a high speed position H. And a sub-transmission lever 3F for shifting the speed (FIG. 1).

The braking device includes an operation wire 30 having one end connected to a front wheel steering device 2a linked to the steering wheel 2.
The operation wire 30 is located behind the pedal shaft 3 that operates the rear wheel brake 3a via the brake rod 31.
The automatic braking device 5 includes an "intermediate operating body 4" for changing the operating direction, which interlocks and connects the other end of the pedal shaft 3 with the pedal shaft 3.

The intermediate operating body 4 is provided with a linkage release mechanism 6 of the automatic braking device 5 which can be disengaged from the other end of the operation wire 30.
(FIG. 3) is provided at the left side position of the handlebar 2 and is also linked to the auxiliary transmission lever 3F.

The linkage release mechanism 6 is provided with a release wire 60 that is connected to the left and right intermediate operating bodies 4 on a connection release lever 61 that is pivoted up and down.
When the sub-transmission lever 3F is operated to the high-speed position H shown in FIG. 1, the high-speed release wire 63 provided on the release lever 62 operated by the operation is connected, and the connection release lever 61 is engaged during high-speed traveling. It is configured to automatically switch from the operation position to the cutting operation position. (Automatic Braking Device 5) The detailed structure of the automatic braking device 5 will be described. First, the left and right brake pedals are respectively supported by the right and left brake pedals 3R and 3L so as to be independently rotatable by the body. Rear wheel brake 3a
The brake operation piece 32 connected to the brake rod 31 is integrally provided on the left and right pedal shafts 3 protruding.

The right and left brake pedals 3R and 3L are separately biased by the buffer members 40 (springs) of the "intermediate operating member 4" on the left and right pedal shafts 3 in the braking direction. Boss part 41 of united 41
a is loosely supported (FIG. 6).

As shown in FIGS. 6 to 8, the engaging body 41 presses and rotates the brake operating piece 32 in the direction of the arrow, pulls the corresponding brake rod 31, and operates the rear wheel brake 3a. To be able to brake. (Intermediate operating body 4 and linkage release mechanism 6) Next, the configuration of the intermediate operating body 4 will be described with reference to FIGS.

The intermediate operating body 4 is provided with a support shaft 45 which is disposed substantially parallel to the rear of the pedal shaft 3 on both sides of the intermediate case 1c.
And the other end of the operation wire 30 provided on the front wheel steering device 2a and the connection release lever 61 of the linkage release mechanism 6
(FIG. 3) are connected to the other end of the release wire 60 by detouring from the front side to the rear side of the fuselage, and when the linkage release mechanism 6 is in the “entered state” shown by a solid line in FIG. ,
The rear wheel brake 3a on the turning side of the vehicle body can be automatically braked in accordance with a rotation operation (handle operation) of the handle 2 beyond a certain value.

When the linkage release mechanism 6 is raised and turned off as shown by the dotted line in FIG. 3, the automatic braking operation state at the time of turning as described above can be released and the normal braking operation state can be set. It is configured as follows.

That is, the intermediate operating body 4 has a plate-like operating plate 46 (FIGS. 4 and 6) standing upright on a support shaft 45 protruding laterally rearward at substantially the same height as the pedal shaft 3. In this state, the operating plate 46 is rotatably pivoted, and an engagement pin 30a provided at an end of the operation wire 30 is slidably provided in the operation plate 46 in an engagement hole 46a formed in a laterally elongated hole shape on the rear side. It is configured to be able to engage.

Further, as shown in FIG. 6, a hook-shaped connection switching member having a hook portion 7a is provided at the front side of the engagement hole 46a at the neutral position of the engagement pin 30a so as to be releasably engaged. 7 is rotatably supported by a support pin 70. The hook 7a side of the connection switching member 7 is pulled and urged by a pull spring 71 provided at the end of the operation plate 46, and the other end is connected to the release wire 60.

The operating plate 46 includes a buffer 4 made of a coil-shaped spring material provided between the engaging portions 41 extending above the support pins 70 and the engaging members 41.
It is connected by 0.

The intermediate operating body 4 configured as described above is
In the “uncoupled position” in which the hook portion 7a of the connection switching member 7 and the engagement pin 30a are not engaged with each other as illustrated in FIG. Since the pin 30a is freely slid into the engaging hole 46a, the operating plate 46 does not rotate the brake operating piece 32 in the direction of the arrow through the pin on which the end of the buffer 40 is hooked and the engaging body 41. The above-mentioned "normal braking operation state" can be achieved.

At this time, the left and right operation wires 30 in the illustrated example are
Are disposed on both sides of the steering shaft 25 of the front wheel steering device 2a shown in FIG. 1, so that the operating direction of the engagement pin 30a linked to the left and right operation wires 30 accompanying the steering operation is
In the engagement holes 46a of the left and right intermediate operating bodies 4, they move in opposite directions.

When the handle 2 is at the neutral position when the vehicle is moving straight, the engagement pin 30a is located substantially at the center of the engagement hole 46a. When each of the brake pedals 3L and 3R is depressed, the pedal shaft 3 and the brake actuating piece 32 rotate in the direction of the arrow to cause the brake rod 31 (FIG. 1) to operate the rear wheel brake 3a on the depressed side. The normal braking operation state where braking is performed can be performed favorably.

When the disconnection lever 61 of the linkage release mechanism 6 (FIG. 3) is actuated by the solid line in the normal braking operation state as described above, the release wire 60 is loosened and the connection switching member 7 is moved to the position shown in FIG. 7, the hook portion 7a locks the engaging pin 30a at the neutral position, and the hook portion 7a is moved backward (to the right in FIG. 7) of the engaging pin 30a. The automatic braking operation state in which the movement is restricted is set.

When the steering wheel is operated in this state, the operation wire 30 on the body turning side is pulled backward in accordance with the operation, so that the connection switching member 7 engaged with the operation wire 30 is engaged.
Rotates the operating plate 46 rearward (clockwise) around the support shaft 45 against the buffer 40 (spring) via the support pin 70.

By the backward rotation of the operation plate 46, the shock absorber 40 rotates the engaging body 41 about the pedal shaft 3 in the lifting direction.
Abuts against the brake operating piece 32 to rotate the pedal shaft 3 by the urging force of the shock absorber 40, and the rear wheel brake 3a on the turning side is automatically braked through the bracket by the operation of the steering wheel via the bracket. The small turning traveling with the small turning radius of 1 can be performed quickly.

At this time, the intermediate operating body 4 and the pedal shaft 3 are
Since the shaft is connected so as to be interlocked with the rear wheel brake 3a via the shock absorber 40, the intermediate operating body 4 and the pedal shaft 3 need not be separately provided with a connecting member such as a rod, and are required in the braking device. Since the buffer body 40 is installed,
The braking sensation of the rear wheel brake 3a by operating the steering wheel can be improved as if the driver steps on the rear wheel brake 3a, and the device can be more compactly configured with a simple and inexpensive configuration.

In the automatic braking operation state as described above, when the sub-transmission lever 3F is operated to the high-speed position H as shown in FIG.
Through the release wire 63, the connection release lever 61 of the linkage release mechanism 6 is pulled from the entry position indicated by the solid line to the cutting position indicated by the dotted line.

With this operation, the release wire 60 pivots the connection switching member 7 of the intermediate operating member 4 upward against the spring 71, so that the hook portion 7a and the engaging pin 3 are rotated.
0a is released and the normal braking operation state is set again. Therefore, rapid small turning of the body during high-speed running can be prevented well, and stable operation can be performed.

The other end of the shock absorber 40, one end of which is connected to the intermediate operating body 4, is connected to an engaging body 41 fitted externally to the pedal shaft 3, and this engaging body 41 is connected to the intermediate operating body 4 associated with the operation of the handle.
The pedal shaft 3 is engaged with the pedal shaft 3 so that the pedal shaft 3 is operated in the brake operating direction by the turning operation of the brake pedal, and the engagement is released by the independent rotation of the pedal shaft 3 by the brake pedal operation. ing.

Accordingly, when only the brake pedals 3L and 3R are depressed, the linkage with the automatic control device 5 is reliably released, so that the normal braking operation state can be performed lightly.

The automatic braking device 5 includes an operating wire 3 for connecting one end to a front wheel steering device 2a linked to the steering wheel 2.
0, an intermediate operating body 4 for changing the operating direction, which is located behind the pedal shaft 3 that operates the rear wheel brake 3a via the brake rod 31 and interlocks and connects the other end of the operation wire 30 and the pedal shaft 3. It is composed of

Accordingly, the operation in which the rear of the intermediate operating body 4 is bypassed by the operation wire 30 from the front wheel steering device 2a on the front side of the fuselage can be freely performed.

Further, since the height of the intermediate operating body 4 in the vertical direction can be made compact so as to be approximately equal to the operating height of the brake operating piece 32 of the pedal shaft 3, the front of the pedal shaft 3 and the machine Even in a low-floor tractor or the like in which it is difficult to install the automatic braking device 5 below the abdomen, the intermediate operating body 4 and the like do not greatly protrude downward into the space existing behind the pedal shaft 3 and are simple. It can be installed with a simple configuration.

The front wheel steering device is composed of a power steering unit, and it is needless to say that the steering wheel operation can be performed lightly like a normal automobile.

[0039]

The work vehicle control device according to the present invention includes a left and right brake pedals 3L and 3R and an automatic brake device 5 that automatically activates a rear wheel brake 3a on the turning side of the fuselage according to the operation of the steering wheel. The automatic braking device 5 includes an operating wire 30 that connects one end to a front wheel steering device 2a linked to the steering wheel 2, and a pedal shaft 3 that operates a rear wheel brake 3a via a brake rod 31. It is characterized in that it comprises an intermediate operating body 4 for changing the operating direction, which is located at the other end of the operation wire 30 and the pedal shaft 3 in an interlocking manner.

Therefore, the intermediate operating body 4 and the like of the automatic braking device 5 can be compactly installed near the pedal shaft 3.

Further, the intermediate operating body 4 is provided with the linkage release mechanism 6 of the automatic braking device 5 which can be disengaged from the other end of the operation wire 30, so that the other end of the operation wire 30 is linked. Can be canceled, and when the automatic braking operation state is changed to the normal braking operation state, the members subsequent to the intermediate operating body 4 are prevented from being involved in the steering operation, and the steering operation can be performed smoothly.

Further, the intermediate operating body 4 and the pedal shaft 3 are interlocked with each other via the shock absorber 40 for the rear wheel brake 3a, so that braking accompanying the steering operation in the automatic braking operation state is appropriately performed. Can be performed.

Further, the other end of the shock absorber 40 having one end connected to the intermediate operating body 4 is connected to an engaging body 41 externally fitted to the pedal shaft 3, and the engaging body 41 is connected to the intermediate operating body 4 by operating the handle. The pedal shaft 3 is engaged with the pedal shaft 3 so that the pedal shaft 3 is operated in the brake operation direction by the rotation operation, and the engagement is released by the independent rotation of the pedal shaft 3 by the brake pedal operation. It is characterized by:

Accordingly, when the brake pedal is depressed, the linkage with the automatic braking device 5 is reliably released, so that the depressing operation can be performed lightly.

[Brief description of the drawings]

FIG. 1 is a side view of a body of a tractor showing an embodiment of the present invention.

FIG. 2 is a plan view showing a configuration of a main part of FIG.

FIG. 3 is a side view showing a configuration of a link release mechanism and an intermediate operating body on the right side in FIG. 1;

FIG. 4 is a plan view of the intermediate operating body.

FIG. 5 is a side view showing an engagement state of a connection switching member and an engagement pin of the intermediate operating body.

FIG. 6 is a side view showing a posture of the intermediate operating body in a normal braking operation state.

FIG. 7 is a side view showing a posture of the intermediate operating body in an automatic braking operation state.

FIG. 8 is a side view of a braking state of the intermediate operating body in an automatic braking operation state.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Body (work vehicle) 2 Handle 3L, 3R Left and right brake 3a Rear wheel brake 4 Intermediate operating body 5 Automatic braking device 6 Link release mechanism 7 Connection switching member 8 Buffer 30 Operation wire 31 Brake rod 40 Buffer (spring) 41 Combination 60 release wire

Claims (4)

[Claims] 1. A working vehicle comprising: a left and right brake pedals (3L, 3R); and an automatic braking device (5) for automatically operating a rear wheel brake (3a) on the turning side of the vehicle body in response to a steering operation. An operation wire 30 for connecting one end to a front wheel steering device 2a linked to the second wheel 2; a brake rod 31 for operating a rear wheel brake 3a behind the pedal shaft 3; A braking device for a working vehicle, comprising an intermediate operating body 4 for changing the operating direction, wherein the shaft 3 is interlocked and connected. 2. The braking device for a working vehicle according to claim 1, wherein the intermediate operating body includes a linkage release mechanism of an automatic braking device that is detachable from the other end of the operation wire. 3. The brake system for a working vehicle according to claim 1, wherein the intermediate operating body 4 and the pedal shaft 3 are interlockingly connected via a buffer 40 for the rear wheel brake 3a. 4. A buffer 4 having one end connected to the intermediate operating body 4.
0 is connected to an engaging body 41 externally fitted to the pedal shaft 3, and the engaging body 41 is an intermediate operating body 4 associated with a handle operation.
The pedal shaft 3 is engaged with the pedal shaft 3 so that the pedal shaft 3 is operated in the brake operating direction by the turning operation of the brake pedal, and the engagement is released by the independent turning of the pedal shaft 3 by the brake pedal operation. Claim 1
Or the braking device for a working vehicle according to 2 or 3.