JPH09301138A - Side brake switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To safely operate a brake device of a working vehicle adapted to conduct the turning operation during work by a switch. SOLUTION: In a working vehicle where braking mechanisms disposed on right and left axle driving parts can brake independently right and left by a brake switch 41, the brake switch 41 is disposed in a switch case 40 in such a manner as to freely slide vertically, a switch elevation driving mechanism is arranged below the switch case 4, and at the time of high speed running, the switch elevation driving mechanism is driven to store the brake switch in the switch case.

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 one side brake is operated by operating a brake switch when a sharp turn is made during work.

[0002]

2. Description of the Related Art Conventionally, in a working vehicle such as a tractor, a pair of brake pedals is provided on a step so that the left and right side brakes can be operated. In this tractor, when traveling on the road, a pair of brake pedals are connected and turning is performed by operating a steering handle.
Further, during work such as cultivating work, a sharp turn operation can be performed by operating the steering handle and the side brake. However, in consideration of safety, if you forget to perform the connecting operation, one of the brake pedals may be depressed, which may have a negative effect, and the left and right brake pedals may be mistakenly depressed when turning. Brake pedal is preferred. In order to use this one brake pedal, the applicant has arranged left and right brake switches on the lifting lever, and actuating the brake switches actuates the braking mechanism provided in the transmission case, so that The technique of stopping the rotation and turning around the rear wheel on that side has been proposed in Japanese Patent Application No. 7-176976.

[0003]

However, in the prior art, the elevating levers for disposing the left and right brake switches are in a state of protruding above the side cover near the driver's seat, and are parallel to the elevating levers. When operating other operating levers such as the plowing depth setting lever to be installed, it is expected that the brake switch is touched and malfunction occurs. Therefore,
There is a demand for a structure in which the brake switch cannot be operated except during the work of rapidly turning the machine body.

[0004]

In order to solve such a problem, the present invention is a work in which a braking mechanism disposed in the left and right axle drive portions can be independently braked by using a brake switch. In a vehicle, the knob of the brake switch is arranged in a switch case so as to be slidable up and down, and a switch elevating drive mechanism is arranged under the switch case, and the switch elevating drive mechanism is driven at high speed traveling to switch the brake switch. It was configured to be stored in the case.

[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. 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, and FIG. 4 is a brake switch. FIG. 5 is a circuit diagram showing a control structure of a brake arm, FIG. 5 is a front sectional view of a brake switch which can be housed inside a body cover of the present invention, FIG. 6 is an electric circuit diagram for starting a starter motor, and FIG. 7 is a brake operation state. FIG. 8 is a partial plan view of the operation panel, and FIG. 8 is a partial front view of the front accelerator case in which the marker is arranged.

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, a dashboard 2 is erected on the rear end of the frame F, and a steering wheel type handle 3 is projectingly provided on the upper end of the dashboard 2. An operation panel 12 is disposed in the section, a PTO changeover switch 14 is disposed in the rear surface thereof, and a step portion 4 is formed by utilizing the upper surface of the frame F behind and immediately behind the dashboard 2. A brake pedal 6 is provided on the right front part of the frame F so as to project upward from below the frame F, and a clutch pedal 13 is provided on the left side of the frame F. A seat 5 is arranged behind the step portion 4, and a body cover 65 on the side of the seat 5 is arranged.
A gear shift lever 7, an auxiliary gear shift lever 46, a lifting lever 8 and a plowing depth setting lever 9 are provided on the upper part of the machine so that the machine cover 65
A PTO gear shift lever 15 is arranged on the front surface. And
Power is transmitted from the engine E to the mission case M, and the rear wheels 11 and 11 are driven via axles 45 that project laterally from the rear of the mission case M.
Further, power is transmitted to the front of the mission case M to drive the front wheels 22, 22 which are steered by the steering wheel 3.

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 are vertically rotated by hydraulic pressure are extended to the rear of the machine body, and the lower links 55, 55 are connected via lift rods connected to the tips of the lift arms 57, 57.
Are linked. The lift arms 57, 57 are rotated up and down by expansion and contraction of a hydraulic cylinder, and the lift arms 57, 57 are operated by operating the elevating lever 8 and the working depth setting lever 9.
57 is configured to be moved up and down to reach a desired depth.

As shown in FIG. 8, the front accelerator case 60 for supporting the front wheels 22 and 22 is provided with a differential mechanism 50 at the center of the left and right sides to transmit power to the left and right sides. There is. King pins 51 are rotatably supported at both ends of the front accelerator case 60.
A front gear case 61 is rotatably fitted on the outer periphery of the front wheel 1, and the front wheel 10 is axially supported by the side portion of the front gear case 61, and the front wheel 10 is driven via bevel gears 52 and 53. Further, a knuckle arm 62 is projected above the front gear case 61, and the knuckle arm 62 is interlocked with the handle 3 via a tie rod or the like.
It enables 0 steering operation.

Further, on the upper surface of the front gear case 61, a marker 63, which is a standard for the vehicle width of the working machine B (the rotary cultivator B in this embodiment), can be attached. As shown in FIG. 8, the front gear case 61 is
Of the stay 22 protruding upward from the upper surface of the stay 22, and a sliding cylinder 23 having an axial center in the left-right and front-rear directions is fixed to the upper end of the stay 22 and slidable in the left-right direction inside the sliding cylinder 23. The moving shaft 24 is fitted, the marker 63 is projected downward from the end of the sliding shaft 24, and the position of the marker 63 is set to the working machine B.
The sliding shaft 24 can be fixed by the fixing screws 25 in accordance with the positions of both ends of the. Further, the sliding shaft 24 is inserted into and fixed to the sliding cylinder 23 in the front-rear direction so that it can be stored.

Therefore, when the machine body is positioned so that the marker 63 passes over the end of the cultivated land or the edge of the ridge, the end of the working machine B is allowed to be along the end of the cultivated land to enable plowing work. ing. Further, since the stay 22 supporting the marker 63 is fixed to the front gear case 61, even when the cultivated land is bent, the marker 63 can be aligned with the end of the cultivated land, so that accurate cultivating work can be performed. It can be carried out.

Next, the PTO changeover switch of the PTO drive shaft for driving the working machine B will be described. As shown in FIG. 6, the PTO changeover switch 14 is turned off.
It can be switched to "independent" or "interlocked" and has contacts 14a, 14b, 14c corresponding to each.
In the "cut" position, the contact 14a is open,
The PTO shaft is in a non-rotating state, and in the "interlocked" position, the contact 14b is in a position where it is connected to a switch 28 provided on the PTO clutch and the traveling clutch pedal, which will be described later, and the PTO shaft rotates only when the traveling clutch pedal 13 is depressed. In the "independent" position, the contact 14c is connected to the PTO clutch, and the PTO shaft is rotated regardless of the depression of the traveling clutch pedal 13.

Then, the starter motor 27 is connected in series with the start switch 26 and the switch 28, and the interlock switch 28 has a "break" contact 14a 'of the PTO switch 14.
And "interlocking" contacts 14b 'are connected.

In such a structure, when the engine E is started, conventionally, the main shift lever 7 and the sub shift lever 4 are used.
6. Set the PTO gear shift lever 15 to the neutral position and set the PTO selector switch 14 to "OFF" to set the traveling clutch pedal 13
The safety switch was activated and the engine could not be started unless the vehicle was depressed. However, in this embodiment, when the traveling clutch pedal 13 is depressed at the "interlocked" position, the rotation of the PTO shaft is stopped, and the "independent" Since the contact point 14c 'is not connected to the starter motor 27, when the traveling clutch pedal 13 is depressed at the "interlocked" position and the "disengaged" position,
The engine can be started. Therefore, PTO
The safety switch in the neutral position of the speed change lever 15 is not necessary and can be omitted, and the engine can be operated without operating the PTO selector switch 14 which is disposed in the unhandled place under the handle 3 in the "interlocking" position. E can be started.

Next, as shown in FIG. 2, the structure of the braking portion is as follows.
The power changed by the transmission case M is transmitted to the differential mechanism D via the drive gear, and the left and right axles 45, 45 are rotated by the differential mechanism D. A reduction gear 47 is fitted to the outer ends of the axles 45 and 45, and a gear 48 is fitted to the support shaft 72 that supports the rear wheels 11 and 11.
The rear wheels 11 and 11 are driven by meshing with. Further, friction plates 49, 49 constituting a multi-plate type braking mechanism are arranged in the middle of the axles 45, 45, and pressing plates 70, 70 are slidably arranged on the side surfaces of the friction plates 49, 49. Is
The pressing plates 70, 70 are slid by a braking mechanism, the pressing plates 70, 70 are connected to the brake pedal 6 and a brake actuator via a cam mechanism, etc., and the pressing plates 70, 70 are slid to generate a friction plate. 49
・ By pressing 49 ..., it is possible to brake.

By depressing the brake pedal 6 by one, the pressing plates 70 on both sides are pressed to brake. The brake actuator is adapted to be braked by a brake switch 41 arranged in the vicinity of the seat 5 when turning during work. That is, as shown in FIG. 2 and FIG. 3, two arms 1 extending upward are provided on the pivot base 6a of the brake pedal 6 which is pivotable in the vertical direction.
6 and 16 are projected, and a brake rod 17 is pivotally connected to the tip of each arm 16. 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 operating rods 21 and 21 are pivotally connected to the other ends of the brake arms 18, and the central portion of the brake arms 18 is pivotally supported by a support shaft 20.
The brake arm 18 can be rotated around. Therefore, when the brake pedal 6 is depressed, the left and right actuating rods 21, 21 are moved rearward, and the pressing plate 70
Presses the friction plates 49, 49 ..., and the axles 45 on both sides
・ 45 is braking.

When the left and right braking mechanisms are individually operated, braking is performed by the brake switches 41 for braking the left and right axles arranged near the seat 5. 3 and 4
As shown in FIG. 5, the left and right contacts of the brake switch 41 are connected to the controller C, and the controller 3 further includes a solenoid 3 for switching the control valve V.
It is connected to 8.39. The control valve V is a 4-port 3-position switching electromagnetic valve, and its secondary side is connected to brake cylinders 68 and 69 as brake actuators via oil passages 66 and 67. The brake cylinders 68 and 69 are single-acting type, have a compression spring inside and urge the rod 73 to contract. The tips of the rods 73, 73 are pivotally connected to the left and right brake arms 18, 18. An oil passage 74 is connected to the primary side of the valve V, and the oil passage 74 is connected to a hydraulic pump P that receives and drives the power of the engine E. The oil passage 75 is connected to the tank (mission case).

With the above construction, when one of the above-mentioned brake switches 41 is operated in the turning operation during work, the solenoid 38 (39) on the selected side is excited via the controller C, and the control valve V Is switched, the oil passage 74 and the oil passage 66 (67) are connected, pressure oil is sent to the cylinder 68 (69), the rod 73 is extended, and the brake arm of the left (right) side brake mechanism. 18 is rocked to brake the axle 45. At this time, the fastening pin 19 does not slide in the elongated hole 17a to operate the other brake. When the brake switch 41 is released, the solenoid returns to the neutral position and the solenoid turns off.
It becomes F.

In the present invention, the brake switch 41 is housed inside the switch case during high speed traveling such as road traveling. That is, as shown in FIG. 5, a switch port 65a for attaching the brake switch 41 to the cover 65 is opened, and the switch port 65a is opened.
The switch case 40 is inserted and fixed in. A brake switch 41 is slidably inserted in the switch case 40 in the vertical direction, and a tip end of an operating rod 42 of a solenoid 44 is fixed to the lower surface of the brake switch 41. Further, a compression spring 77 is provided inside the solenoid 44 to urge the lower end of the operating rod 42 upward, and when the solenoid 44 is not operated, the brake switch 41
Is projected upward from the switch port 65a so that it can be operated.

Further, the solenoid 44 is connected to a controller C, and the controller C is further connected to a high speed position switch 78 arranged at a high speed position of a lever guide of the auxiliary speed change lever 46, and the auxiliary speed change lever 46 is connected. When the switch is switched to the high speed position, the high speed position switch 78 is turned on, the controller C supplies power to the solenoid 44, pulls the operating rod 42 against the urging force of the compression spring 77, and the brake switch 41 to the switch case 40.
It is housed inside so that the brake switch 41 cannot be operated. Then, when the auxiliary transmission lever 46 is switched to the medium speed or the low speed, such as during work, the high speed position switch
8, the solenoid 44 does not operate, the compression spring 77 pushes the operating rod 42 upward, and the brake switch 41 is projected above the cover 65 to enable a sudden turning operation by the brake switch 41.

The side brakes can be operated by the left and right brake pedals 6 in place of the brake switch 41. At this time, both brake pedals are connected by a connector (not shown) so that both brake pedals can be operated on the road. It is possible to press the brake pedal at the same time.At this time, the connected / unconnected state of the connector is indicated by a lamp,
Safety can be improved.

That is, as shown in FIG. 7, the connection display lamp 29 and the independent operation lamp 3 are provided on the operation panel 12.
0 is provided, the connection indicating lamp 29 is a lamp that lights up in blue when both brake pedals 6 and 6 are connected using a connector, and the independent operation lamp 30 is in a state where the connection by the connector is disconnected. It lights up in red to alert the operator.

However, if the red lamp is lit in the working state, it may give an illusion that the device is abnormal. Therefore, a rotatable shield plate 31 is provided near the independent operation lamp 30.
Is arranged so that the independent operation lamp 30 is hidden during work. That is, as shown in FIG. 7, the pivot shaft 32 is projected to the side of the independent operation lamp 30, and
A shielding plate 31 is fixedly installed on the. On the other hand, the operation panel 1
2, the contact plate 33 is projected onto the pivot shaft 32,
An end portion of the contact plate 33 is biased upward by a spring 34, and an end portion of a pushing member 35 formed of a solenoid or the like is arranged so as to come into contact with an intermediate portion of the contact plate 33. The member 35 is connected to a controller, and the controller is connected to a sensor for detecting the rising position and the descending position of the working machine. Therefore, when the connector is disconnected, the independent operation lamp 30, which is a red lamp, is turned on, and when the elevating lever 8 is switched to the lower position, the sensor is turned on, the pushing member 35 is extended, and the shield plate. 31 is rotated, the independent operation lamp 30 is covered, and the operator can work without worrying about the lighting of the red lamp.

[0023]

As described above, the present invention has the following effects. That is, when traveling at high speed such as traveling on the road, the auxiliary shift lever is switched to the high speed position so that the brake switch is housed in the switch case, and the brake mechanism is operated by the operator's erroneous operation to operate the vehicle. be able to. Also,
At the time of work, since the brake switch projects above the switch case, the side brake operation can be easily performed, and the operability of the machine body can be improved.

[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.

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

FIG. 5 is a front sectional view of a brake switch that can be stored in the cover of the present invention.

FIG. 6 is an electric circuit diagram for starting the starter motor.

FIG. 7 is a partial plan view of the operation panel showing a brake operation state.

FIG. 8 is a partial front view of a front accelerator case in which a marker is arranged.

[Explanation of symbols]

 6 Brake pedal 40 Switch case 41 Brake switch 44 Solenoid 46 Auxiliary shift lever 65a Switch port 78 High-speed position switch

Claims (1)

[Claims] 1. In a working vehicle in which a braking mechanism disposed on the left and right axle drive parts is capable of independently braking by using a brake switch, the brake switch is disposed on a switch case so as to be slidable up and down. The side brake switch is characterized in that a switch elevating drive mechanism is arranged under the switch case, and the switch elevating drive mechanism is driven during high-speed traveling to house the brake switch in the switch case.