JP3070150B2 - Tractor lift arm restraint system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tractor lift arm restraint system, and more particularly to a tractor cabin in which a rear window of a tractor is opened so as not to raise a working device by a lift arm with respect to a vehicle body. Prevent collision of work equipment with rear window.

[0002]

2. Description of the Related Art In a configuration in which a working device is connected to a rear portion of a tractor body and height control is performed by raising and lowering a lift arm, a rear window of a tractor cabin is moved rearward. If the working device rises unexpectedly while the door is largely open, it may collide with the rear window and be damaged.

[0003]

The present invention relates to a relationship between a lift arm 3 which is connected to a working device 2 provided at a rear portion of a tractor body 1 and which moves up and down, and a rear window 5 of a cabin 4 which is opened and closed above the arm. In addition, a lift arm restraining device for a tractor including a lift restraining device 6 that restrains the lift of the lift arm 3 by opening the rear window 5 is provided.

[0004]

Function and effect of the invention Rear window 5 of cabin 4
When the lifting device 3 is moved up and down to lift the working device 2 in a state where is closed, the working device 2 is freely lifted. When the rear window 5 is opened, the lift restraint device 6 operates, the lift of the lift arm 3 is restrained, and the working device 2 is not lifted.

Therefore, in a state where the rear window 5 is opened rearward, the working device 2 is not inadvertently raised, and the lifting operation of the lift arm 3 can be performed safely.

[0006]

1 to 4, a tractor body 1 has an engine 7 mounted on a front part thereof, a cockpit 10 provided between fenders 9 of rear wheels 8, and a front wheel 11 is operated by operating a steering handle 12. You can drive toward. The cabin 4 extends over the steering handle 12 and the cockpit 10.
It is equipped with. The cabin 4 has a roof, a windshield, left and right door glasses, a rear window 5 that can be opened and closed, and the like so that the surroundings can be easily seen through.
The rear window 5 is provided with an open / close hinge 13 at the upper end, and the lower end can be opened and rotated rearward.

At the rear of the vehicle body 1, a lift arm 3 is vertically rotated by a hydraulic cylinder mechanism. The lift arm 3 is connected to a lower link 14 by a lift rod 15, and the lower arm 14 is vertically rotated by the lift arm 3. Can be rotated with respect to the vehicle body 1 to move the working device 2 up and down. 16
Is the top link. In the example shown in the figure, a tillage device is used as the working device 2, and the working device 2 is configured so that the tiller is tapped in cooperation with a power take-off shaft from the vehicle body 1 side. Reference numeral 17 denotes a tillage claw, and reference numeral 18 denotes a tillage cover. A cultivator 19 is provided above the tillage device 2.
Is attached to the telescopic hitch 20 so that the bracket hitch 21 can be freely attached to and detached from the telescopic hitch 20.
Is rotated up and down around the support shaft 23 so that the work position hole 24 is
And the non-working position hole 25 in the inverted posture. Reference numeral 26 denotes a handle for adjusting the vertical angle of the telescopic hitch 20 with respect to the tilling device 2.

A window limit switch 27 for detecting the open / close position of the rear window 5 is provided at the open / close position of the rear window 5 of the cabin 4 to constitute the restraint device 6. When the rear window 5 is opened, the window limit switch 27
Is in the ON state, the lift arm 3 can be turned on even if the lift control switch CPU provided near the cockpit 10 is turned on by the lift controller CPU having a microcomputer.
Arm raising output 29 for outputting the output to the ascending side is stopped. Note that the lift arm lowering output 30 by the raising / lowering control switch 28 does not have to be suppressed.

Further, in a configuration in which the open position of the rear window 5 is obstructed in relation to the cultivator 19 in the tilling work apparatus 2, the posture in which the cultivator 19 is transferred to the non-work position hole 25 is changed to the non-work position. 25, the detection limit may be turned on by the work limit switch 31. When the window limit switch 27 and the work limit switch 31 are simultaneously turned on, the lifting output of the lift arm 3 may be stopped.

In FIG. 5, the difference from the above example is that the operation of the position lever for raising and lowering the lift arm 3 is intermittent at the raising output 29, and the displacement amount X of each intermittent raising operation is different. When the constant value α which is a positive constant is reached, the raising output 29 by this position control is stopped, and only when the operation change position of the position lever does not reach the constant value α, a small amount of output is performed to lift the lift arm 3. It can be raised.

In FIGS. 6 and 7, in the transmission for the power take-off shaft interlocking between the rear end of the vehicle body 1 and the working device 2, the PTO lever 32 for shifting the power take-off transmission is neutral. When it is in the position N, this is detected by the neutral sensor 33. At this time, when the PTO clutch is operated to be engaged, the engagement of the PTO clutch is detected by the clutch sensor 34.
Turns on, the PTO clutch cannot be engaged, and
This is notified by an alarm device 35 such as a pilot lamp. When the PTO lever 32 is being shifted to the low speed position L or the high speed position H, the neutral sensor 33
Is in the OFF state. The PTO clutch is a wet hydraulic clutch type.

[Brief description of the drawings]

 The figure shows an embodiment of the present invention.

FIG. 1 is a side view.

FIG. 2 is a side view of a part thereof.

FIG. 3 is a control block diagram.

FIG. 4 is a flowchart of the partial control.

FIG. 5 is a control flowchart showing a partially different embodiment.

FIG. 6 is a block diagram of a partially different invention;

FIG. 7 is a side view of a part thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tractor body 2 Working device 3 Lift arm 4 Cabin 5 Rear window 6 Lift restraint device

Claims (1)

(57) [Claims] 1. A relationship between a lift arm 3 which is connected to a working device 2 provided at a rear portion of a tractor body 1 and rises and lowers, and a rear window 5 of a cabin 4 which is opened and closed thereabove. A tractor lift arm restraint device provided with a lift restraint device 6 for restraining the lift of the lift arm 3 by opening.