JPH0924807A - Brake mechanism for working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make structure in which a brake pedal for operating right and left side brakes by means of only one brake pedal, and the side brakes can be independently braked by t' button operation. SOLUTION: In a working vehicle capable of being turned by turning movement of a steering handle and operation of a side brake, brake mechanisms are respectively provided on right and left axle driving parts. A brake pedal 6 and two right and left brake cylinders 31, 32 are connected to the braking mechanisms, the right and left sides are simultaneously braked by the operation of the brake pedal 6 and made to be independently braked by the right and left brake cylinders 31, 32, the right and left brake cylinders 31, 32 are connected to right and left brake switches arranged on an raising and lowering lever for raising and lowering a working machine, so as to be braked by the operation of the brake switches.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake device for a working vehicle in which a lever portion is used to perform a turning operation during work.

[0002]

2. Description of the Related Art Conventionally, a button type steering operation device has been known as a steering device for a crawler type traveling device such as a combine. For example, there are techniques disclosed in Japanese Utility Model Laid-Open No. 59-11626 and Japanese Utility Model Laid-Open No. 62-134339. However, a steering wheel type steering wheel such as a tractor is provided with a pair of left and right brake pedals so that a side brake can be operated. In this tractor, the turning operation when traveling on the road is performed by operating the steering wheel.
Also, in the case of cultivating work and the like, a sharp turn operation can be performed by operating the steering handle and the side brakes. In this side brake, two brake pedals are arranged side by side on the front part of the step part, and by operating these two brake pedals individually, the braking mechanism provided inside the mission case on the stepped side is activated. hand,
The rotation of the axle on that side was stopped so that the vehicle could turn around the rear wheel on that side. Also, when traveling on the road, the traveling speed becomes faster, and if you depress only one side, you will make a sharp turn.Therefore, when traveling on the road, connect the brake pedals that are installed side by side with the connector, and even if you depress one, both will be depressed together. , Simultaneously activate the left and right braking mechanisms,
I was trying not to be a one-sided effect.

[0003]

As described above, in the structure in which two brake pedals juxtaposed at the step portion are projected, both brake pedals can be simultaneously depressed by connecting with the connector as described above when traveling on the road. ,
At the time of work, the connector was removed to brake independently, but since the connection and disconnection operation by this connector was done manually, the connection operation of the connector was done when entering or leaving the field. It was forgotten and there was a demand for a structure that could be easily connected.

[0004]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is directed to turning a steering wheel,
In a work vehicle that can be turned by operating side brakes, braking mechanisms are provided on the left and right axle drive parts,
A brake pedal and two left and right brake actuators are connected to the braking mechanism, the left and right sides are braked by the operation of the brake pedal, and the left and right brake actuators can independently brake the left and right brake actuators. It is connected to the left and right brake switches arranged on the lifting lever for lifting and lowering, and braking is possible by operating the brake switches.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The problems to be solved by the present invention and the means for solving them are as described above. Next, the configuration of the embodiment shown in the accompanying drawings will be described. FIG. 1 is an overall plan view of the tractor, FIG. 2 is a layout view showing a drive structure of a rear wheel axle, FIG. 3 is a side view showing a swing structure of a brake arm for operating a braking mechanism of the present invention, and FIG. FIG. 5 is a circuit diagram showing a control structure of a brake arm by a brake switch of the present invention, and FIG. 5 is a front view of an elevating lever provided with the brake switch.

Referring to FIG. 1, a tractor A will be described as a working vehicle adopting this embodiment. On the upper part of the frame F, a hood 1 for mounting the engine E is mounted on the front side, and a dashboard 2 is erected on the rear end of the hood 1 and a steering wheel type handle 3 is projectingly provided. The step portion 4 is formed on the upper side of the frame F on the rear side from immediately after. A brake pedal 6 is provided on the right front portion so as to project upward from below the frame F, and a clutch pedal 12 is provided on the left side. A seat 5 is arranged behind the step portion 4, and a gear shift lever 7, an elevating lever 8 and a working depth setting lever 9 are provided on the side of the seat 5. The front wheels 10 and 10 are steered by the steering wheel 3. From the engine E to the mission case M
Power is transmitted to the rear wheels 11 and 11 via axles 44 and 45 that project leftward and rightward from the rear of the transmission case M.

Further, the working machine B is mounted so as to be able to move up and down by projecting the left and right lower links 55, 55 and the central top link 56 from the rear of the machine body. Further, lift arms 57, 57 that rotate up and down by hydraulic pressure extend rearward at the rear part of the machine body, and the lower links 55.5 are connected via a lift rod connected to the tips of the lift arms 57, 57.
5 are connected. The lift arms 57, 57 include
Pressure oil generated by a hydraulic pump that is connected to a hydraulic cylinder and driven by power from the engine E is sent. The working machine B includes the lifting lever 8 and the working depth setting lever 9
Is operated to raise and lower the lift arms 57, 57 to a desired depth.

Next, a transmission structure is shown in which the power of the engine E is shifted by a transmission in the transmission case M, and after shifting, the power is transmitted to the rear wheels 11 and 11 via an axle drive mechanism to enable braking. 2 is used for the explanation. The power changed by the mission case M is transmitted to the diff mechanism D via the drive gear.
Is transmitted to the differential ring gear 41. Inside the diff ring gear 41, diff pinion gears 42, 42 that rotate integrally with the diff ring gear 41 are loosely fitted.
The differential side gears 43,
44, the differential side gears 43, 44 are engaged with the differential pinion gears 42, 42, and the rotation of the differential ring gear 41 is transmitted to the axles 45, 46.

A reduction gear 47 is fitted on the outer ends of the axles 45 and 46, and the reduction gear 47 is connected to the rear wheel 11.
The rear wheels 11 and 11 are driven by meshing with a gear 48 fitted to a support shaft 52 that supports 11. Also, the axle 45
The friction plates 49, 49 forming a multi-plate braking mechanism are fitted and inserted in the middle of 46, and the pressure plates 50, 50 are slidably arranged on the side surfaces of the friction plates 49, 49. 50 and 50 are slid by the braking mechanism of the present invention, the crimping plates 50 and 50 are connected to the brake pedal 6 and the brake actuator through a cam mechanism or the like, and the crimping plates 50 and 50 are slid to make friction plates. 49
・ By pressing 49 ..., it is possible to brake.

The actuating rods 21, 21 for actuating the crimp plates 50, 50 and the brake pedal 6
The connecting structure with and will be described with reference to FIGS. The rotation base 6a of the brake pedal 6 is a cylinder having a shaft center in the left-right direction.
Is vertically rotatable about the pivot shaft 15.
The rotating base 6a has two arms 16.1.
6 and project the brake rod 17 to the end of each arm 16.
Are linked together. The brake rods 17 and 17 extend rearward, and elongated holes 17a and 17a are opened at the rear ends of the brake rods 17 and 17, respectively, and fastening pins 19 projecting from one end of the left and right brake arms 18 and 18 into the elongated holes 17a and 17a. Is loosely fitted. On the other hand, the actuating rods 21 and 21 are pivotally connected to the other end of the brake arms 18 and 18.
A central portion of the above is pivotally supported by a support shaft 20, and the brake arm 18 is rotatable about the support shaft 20.

That is, when the brake pedal 6 is depressed, the arms 16, 16 are rotated about the pivot shaft 15,
By moving each connecting rod 17, 17 forward, the fastening pin 19 is pulled forward, and each brake arm 18, 18 is pulled.
Is rotated around the support shaft 20 to move the operating rods 20 and 20 rearward, so that the crimping plate 50 crimps the friction plates 49, 49 ...・ 46 can be braked. That is, when traveling on the road, the brake pedal 6 is depressed to brake.

Further, as shown in FIG. 5, the elevating lever 8 is provided with brake switches 25 and 26 for braking left and right axles, and the brake switches 25 and 26 are shown in FIG.
Connected to the controller C as shown in, the brake switches 25 and 26 are turned on when pressed and turned off when pressed again.
It consists of a switch that becomes. The controller C is further provided with an angle sensor 53 for detecting the turning position of the elevating lever 8, an angle sensor 51 provided on the turning base of the handle 3 for detecting the turning angle of the handle 3, and a control valve V. The solenoids 27, 28 for switching and the monitor 54 are connected. The control valve V
Is a 4-port 3-position switching electromagnetic valve, the secondary side of which is connected to brake cylinders 31 and 32 as brake actuators via oil passages 29 and 30. The brake cylinders 31 and 32 are single-acting type, have a compression spring 33 inside, and urge the rod 34 to contract. The tips of the rods 34, 34 are pivotally connected to the left and right brake arms 18, 18. An oil passage 35 is connected to the primary side of the valve V, and the oil passage 35 is connected to a hydraulic pump P that receives and drives the engine E. The oil passage 36 is connected to a tank (mission case) 37.

In such a structure, when the brake pedal 6 is depressed while traveling on the road, the brakes on both sides are braked as described above. When the lifting lever 8 is rotated to the maximum raised position when turning is performed during work, the brake switch 25 or the brake switch 26 provided on the lifting lever 8 is rotated.
Can be turned on. In the lowered position, the vehicle cannot turn, and the ON / OFF state of this brake switch is displayed on the monitor 54. One of the brake switches 25 (2
6) is operated, the solenoid 27 (28) on the selected side is excited via the controller C, the control valve V is switched, the oil passage 35 and the oil passage 29 (30) are connected, and the cylinder 31 ( 32), pressure oil is sent, the rod 34 is extended, the brake arm 18 of the left (right) side brake mechanism is swung, and the axle 46 is braked. At this time, the fastening pin 19 does not slide in the elongated hole 17a to operate the other brake.

When the handle 3 is returned to the original position (within the set angle with respect to the straight traveling direction), the solenoid 27 (28) is automatically turned off by the signal from the angle sensor 51.
Then, the control valve V is returned to the neutral position. At this neutral position, the rod 34 is contracted by the compression spring 33 provided in the cylinder 32, and the pressure oil is transferred to the oil passage 29 (3).
0) is drained through the oil passage 36, the rod 34 contracts, and the braking is released. Then, the other side can be braked similarly. It should be noted that a sensor 59 is provided in the transmission so as to connect with the controller C so that the brake switch 25/26 is not activated even if the brake switch 25/26 is accidentally pressed while traveling on the road so that the brake switch 25/26 can be turned ON only when the work speed is changed. ing. However, it is also possible to configure so as to perform forward acceleration when turning.

[0015]

As described above, the present invention has the following effects. That is, the connector for connecting the left and right work brakes can be eliminated, and a sharp turn can be made by a button operation, the forgetting to set the connector is eliminated, and the operation of depressing the brake pedal can be eliminated, so that the operability can be improved. It can be done and work efficiency is improved. Further, when the vehicle is traveling on the road, both wheels are braked simply by stepping on the foot brake pedal, and the brake operation is the same as that of an automobile, and discomfort can be eliminated.

[Brief description of drawings]

FIG. 1 is an overall plan view of a tractor.

FIG. 2 is a layout view showing a drive structure of an axle for rear wheels.

FIG. 3 is a side view showing a swing structure of a brake arm that operates a braking mechanism of the present invention.

FIG. 4 is a circuit diagram showing a control structure of a brake arm by a brake switch of the present invention.

FIG. 5 is a front view of an elevating lever provided with a brake switch.

[Explanation of symbols]

 M mission case D differential mechanism 3 handle 6 brake pedal 8 lift lever 11 rear wheel 17 brake rod 17a long hole 18 brake arm 19 fastening pin 25 brake switch 26 brake switch 31 cylinder 32 cylinder

Claims (1)

[Claims] 1. In a working vehicle in which turning is possible by turning a steering handle and operating a side brake, a braking mechanism is provided in each of the left and right axle drive parts, and the braking mechanism includes a brake pedal and two left and right brake actuators. The left and right brake actuators can be independently braked by the left and right brake actuators by operating this brake pedal, and the left and right brake actuators are mounted on the lifting levers for lifting the working machine. A braking mechanism for a working vehicle, which is connected to the vehicle and can be braked by operating the brake switch.