JPH04271716A - Front mower of tractor - Google Patents

Abstract

PURPOSE:To prevent forward inclination of a car body when front wheels of car body are braked and safely carry out operation in a front mower of tractor fitted on the front side of car body. CONSTITUTION:A tractor body 2 is advanced by driving front wheels 1 and a mower 3 is fitted on the front side of the tractor body 2. A elevating and lowering control device 5 for elevating and lowering the mower 3 to the car body 2 is controlled and interlocked so that the mower 3 may be changed over from vertically movably lowering position D to neutral position N which carries out vertical movement in grounding state by braking the front wheels 1.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front mower mounted on the front side of a tractor body.

0002

[Prior Art and Problems to be Solved by the Invention] When a front mower of a tractor is driven by driving the front wheels, the weight of the mower acts on the front of the vehicle body, and the drive reaction force is Especially when harvesting on downwardly sloping ground, the rear of the vehicle tends to float up, making it unstable. This invention eliminates these deficiencies.

0003

[Means for Solving the Problems] The present invention is capable of raising and lowering a mower 3 mounted on the front side of a vehicle body 2 that drives a front wheel 1 and operates a brake 4 of the front wheel 1. The structure of the front mower of a tractor is characterized in that it is provided with an elevation control device 5 which changes from a lowered position where it can freely move up and down in a grounded state to a neutral position where it does not move up and down.

0004

[Operation and Effect of the Invention] The tractor body 2 has front wheels 1
, or drive the front wheels 1 and the rear wheels to move forward. When the lift control device 5 is placed in a vertically movable position, the mower 3 is attached to the front side of the vehicle body 2, and the mowing operation is performed in the lowered position where it is in contact with the cutting ground, and the grass is kept at a constant height above the ground. be reaped. When the brake 4 of the front wheel 1 is applied, at the same time, the elevation control device 5 is switched from the vertically movable lowered position to the neutral position, and is fixed so that the mower 3 is not raised or lowered relative to the vehicle body 2. The acting force that causes the rear part of the vehicle body 2 to rotate around the front wheels 1 and rise up is
The mower 3 can be supported by being grounded, and the vehicle body 2 can be prevented from falling forward on a downward slope, etc., and safe reaping work can be performed.

[0005]

[Embodiment] In FIGS. 1 and 2, a tractor body 2 is integrally connected with an engine 6 at the rear, a clutch housing 7, and a transmission case 8 toward the front. , a front axle housing 9 is provided, a front wheel 1 is mounted on a front axle 10 at both left and right ends,
It is configured to transmit power while traveling. Further, the rear axle bracket 11 at the rear end of the vehicle body 2 supports a rear axle housing 13 that can freely roll around the center pivot 12, and the rear axle housing 13 has a rear axle housing 13 on both left and right ends thereof mounted on the front steering post 14. A rear wheel 16 is provided which is steerably interlocked with a steering handle 15, and a center pivot 12 of the rear axle housing 13 is provided from the transmission case 8 part.
The configuration is such that power is transmitted to the rear wheels 16 via a rear wheel transmission shaft 17 which is interlocked throughout the entire vehicle. 18 is the control floor, 1
9 is a cockpit, 20 is a hood, and 21 is a radiator.

[0006] Inside the front axle housing 9, there are provided front wheel brakes 4 for applying braking to transmission shafts extending from a differential gear in the center to each of the left and right front axles 10. You can apply the brakes. Further, the rear wheel brake 23 for the rear wheel 16 is
The rear wheel brake 2 is provided on the center pivot 12 in the center of the rear axle housing 13, and can apply a brake to the shaft portion that transmits power from the rear wheel transmission shaft 17 to the differential gear.
3 sets the brake capacity smaller than the front wheel brake 4, and switches the rear wheel clutch gear in the transmission case 8 using the switching lever to link the rear wheels 16 to create a four-wheel drive driving mode, or 1 can be interlocked to provide a two-wheel drive driving mode.

The mower 3 attached to the front of the vehicle body 2 has a link 25 that is movable up and down relative to a bracket 24 at the front of the vehicle body 2, and a link 27 that is movable up and down relative to the front end of this link 25. 28, and a bracket 30 for the upper part of the mower deck 29 is attached to the lower side of this link 28.
It is grounded and supported by front and rear gauge wheels 31 and 32. The rear end of the link 28 is linked to a hydraulic control valve 34 on the steering post 14 via a rod 33, and the link 25
, 28 is bent upward, the rod 33 is pushed up and the hydraulic control valve 34 is switched from the neutral position N to the raised position U.

Further, an elevating cylinder 37 of a hydraulic circuit including a hydraulic control valve 34 is provided between the lift link 25 and the vehicle body 2, and as the elevating cylinder 37 expands and contracts, the lift links 25 and 28 are raised and lowered. Ru. lift link 2
Between 5 and 28, the structure is such that it can bend and rotate up and down within a predetermined range around the rotation part 27, and any further rotation is possible.
It is configured to be stopped by the tension of a spring 38 or by a stopper or the like. A lever arm 36 that rotates integrally with the base of a lift lever 35 is connected to the lift control valve 34, and by rotating the lift lever 35, the lift cylinder 37 is prevented from expanding or contracting at the neutral position N. In the ascending position U, the lifting cylinder 37 is shortened to raise the lift link 25, and in the descending position D, the lift link 25 is telescopic, and the gauge wheel 31 of the mower 3 is extended by the weight of the mower 3.
, 32 can touch the ground, and the mower 3 can move up and down according to the uneven surface of the ground.

A rod 41 that can be extended and retracted with a turnbuckle 40 is connected to the opposite side of the rotation shaft 39 of the lever arm 36 of the lift control valve 34 from the rod 33 side. is loosely engaged with the elongated hole 43 of the arm 42 that is integrated with the brake pedal 22, and by depressing the brake pedal 22 and applying the brake 4, etc., the rod 41 is pulled down, and the lift lever 35 and the elevation control valve 34 are activated. The elevator control device 5 is configured to be configured in an interlocking manner so as to switch from the lowered position D to the neutral position N. Therefore, during reaping work, the lift lever 35 is moved to the lower position D.
The hydraulic control valve 34 is in a free flow state, and the mower 3 is on the ground and can move up and down due to the unevenness of the ground, but by applying the brake 4, the lift control valve 34 is moved to the neutral position N. The lift links 25, 28 and the vehicle body 2 are integrated, and the acting force that causes the vehicle body 2 to tilt toward the upper front around the front wheels 1 is absorbed. Mower 3 gauge wheels 31, 32
etc. to prevent the rear part of the vehicle body 2 from floating up or falling forward.

[0010] In FIGS. 3 and 4, the points different from the above example are as follows.
The actuator 44 detects the angle between the mower 3 and the vehicle body 2 due to the forward tilting of the vehicle body 2, and throttles the throttle valve 45 of the hydraulic circuit for the lifting cylinder 37 to slow down the upward escape speed of the mower 3. The forward inclination of the vehicle body 2 is supported by the grounding of the mower 3 on the front side, and since the mower 3 rises at a slow speed, it is prevented from receiving an unreasonable load, thereby maintaining safe driving.

The elevating cylinder 37 is provided with a throttle valve 45, which controls the elevating control valve 3 of the elevating cylinder 37 at the lowering position D.
The throttle valve 45 changes the opening degree of the hydraulic circuit 48 between the spool 46 and the spool 46. ,
By communicating in the wide cross-sectional area of the eccentric groove 47, there is little resistance to the expansion and contraction of the lifting cylinder 37 due to the vertical movement of the mower 3, but when the spool 46 is rotated, the narrow cross-sectional area of the eccentric groove 47 When the part is connected, even if the lifting cylinder 37 is forcibly pushed and tries to shorten, the amount of oil discharged from the hydraulic cylinder 37 to the hydraulic control valve 34 side via the eccentric groove 47 is limited.
The rising speed of the mower 3 relative to the vehicle body 2 is limited.

The actuator 44 has an adjustment cam 50 that can be adjusted vertically with respect to the lift link 25 by an adjustment tool 49.
is in sliding contact with the upper surface of the adjustment cam 50 by the spring 51, and when the vehicle body 2 is tilted forward,
7 is shortened, and this actuator 44 is
1 and is rotated upward against the pressure 1 to throttle the hydraulic circuit 48.

[Brief explanation of the drawing]

The figure shows an embodiment of the invention.

FIG. 1: Side view.

FIG. 2 is a partially enlarged side view.

FIG. 3 is a side view of a partial embodiment.

FIG. 4 is a plan cross-sectional view of a portion thereof.

[Explanation of symbols]

1 Front wheel 2 Vehicle body 3 More 4 Brake 5 Lifting control device

Claims (1)

[Claims] [Claim 1] A mower 3 mounted on the front side of a vehicle body 2 that drives a front wheel 1 for traveling can be operated up and down, and can be moved up and down while on the ground by applying a brake 4 of the front wheel 1. A front mower for a tractor, characterized in that a lift control device 5 is provided to set a neutral position from a lowered position without moving up or down.