JPH0230917B2 - HOKOGATAKOTENKI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a walk-behind cultivator configured to adjust the plowing depth by adjusting the height of a tail wheel equipped with a rotary tiller.

[Conventional technology]

The above-mentioned tail wheel is generally adjusted by operating a manual handle, and in order to simplify the operation, a system has been proposed in which the tail wheel is adjusted up and down using a hydraulic cylinder.

[Problem that the invention seeks to solve]

The conventional technique of adjusting the tail wheel using a hydraulic cylinder is only intended to simplify tail wheel adjustment, and in order to respond to changes in plowing depth during work, the valve for the hydraulic cylinder must be manually operated. However, compared to the means of operating a manual handle, the tail wheel up and down adjustment operation is lighter and more quickly transmitted.

Further, since the hydraulic cylinder receives pressurized oil from a pump driven by the engine, it is impossible to adjust the tail wheel using the hydraulic cylinder while the engine is stopped.

An object of the present invention is to stabilize plowing depth by automating adjustment of the tail wheel during work, and to facilitate handling of the tail wheel during non-work.

[Means for solving problems]

The characteristic configuration of the present invention is a tail wheel automatic elevation control mechanism that operates an electric motor for elevating the tail wheel based on the detection result of a sensor that detects the longitudinal inclination of the aircraft to stably maintain the longitudinal inclination angle of the aircraft within a set range. and a battery as a power source for driving the same, the control mechanism is configured to be inoperable when the rotary clutch is disengaged, and a manual switch is provided for directly operating the electric motor in forward and reverse directions. .

[Effect]

According to the above configuration, during plowing work with the rotary clutch engaged, the depth of plowing is stabilized by maintaining the longitudinal inclination angle of the machine body within a certain range.

In addition, even when the rotary clutch is disengaged and the aircraft is not operating, or when the engine is stopped, the tail wheel lifting actuator can be operated freely using the manual switch to adjust the aircraft's longitudinal and tilted posture as desired. can.

〔Effect of the invention〕

Therefore, according to the present invention, the plowing depth adjustment operation during plowing work is completely unnecessary, and the worker can concentrate on operating the machine, thereby improving work efficiency.

Moreover, by disengaging the rotary clutch and disabling automatic tail wheel lifting control during non-operation, it is possible to prevent danger from unexpected automatic lifting and lowering of the tail wheel.

In addition, even when the rotary clutch is disengaged or the engine is stopped, the tail wheel can be adjusted using a manual switch if necessary, making it easier to adjust the attitude of the aircraft when traveling on the road or storing it. be able to.

〔Example〕

FIG. 2 shows a walk-behind cultivator according to the present invention.

This power tiller has a front frame 3 at the front of a transmission case 2 which pivotally supports a pair of left and right propulsion wheels 1, 1.
An engine 4 and a battery 5 are mounted through the transmission case 2, a control handle 6 is attached to the upper part of the transmission case 2, and a rotary tilling device 8 is connected to the rear hitch 7.

The rotary tiller 8 is equipped with a tail wheel 9 that can be raised and lowered. As shown in FIG. 3, this tail wheel 9 is attached to the lower end of a support shaft 11 that is moved up and down by the forward and reverse rotation of a screw shaft 10.
is configured to be driven by a forward/reverse motor 13 with a speed reduction mechanism 12.

The motor 13 is automatically controlled based on the detection result of a longitudinal inclination detection sensor 14 attached to the base of the operating handle 6, and a control circuit thereof is shown in FIG.

In the figure, 15 is a plowing depth setting device composed of a variable resistor, 16 is a comparison circuit for forward rotation, 17 is a comparison circuit for reverse rotation, 18 is a switching circuit for forward rotation of motor, 19 is a relay for forward rotation of motor, and 20 is a relay for reverse rotation of motor. 21 is a relay for reversing the motor, 22 is a main switch, 23 is a switch for starting and stopping automatic tail wheel elevation control, 24 is a manual switch for tail wheel elevation, and 25 is provided on the control handle 6. This is a switch that is closed by the clutch release operation of the rotary clutch lever 26.

Next, the operation of the above circuit will be explained.

Automatic control is enabled by opening the automatic control starting switch 23 and setting it to the "automatic" state, and by switching the rotary clutch lever 26 to the clutch engaged position and opening the switch 25.

Here, when the body longitudinal inclination angle is within a certain range (dead zone) set by the setting device 15, the outputs from both comparison circuits 16 and 17 are both "low" and the motor 13 is stopped. Then, when the wheel 1 enters the recess and the aircraft leans forward beyond the set range, the output of the comparison circuit 16 becomes "high", the relay 19 is activated, the motor 13 is driven forward, and the tail wheel 9 is lowered. . Conversely, when the wheel 1 is on a convex part and the aircraft tilts backward beyond the set range, the output of the comparison circuit 17 becomes "high", the relay 21 is activated, the motor 13 is driven in reverse, and the tail wheel 9 is raised. .

In this way, by controlling the tail wheel 9 to rise and fall so that the longitudinal inclination angle of the machine body is always maintained within a certain range, the plowing depth can be stabilized.

Further, when the switch 23 is closed to be in the "manual" state, the motor 13 can be directly driven in the forward and reverse directions by the manual switch 24. Further, when the rotary clutch lever 26 is operated to the clutch disengaged position, the switch 25 is closed, and even if the switch 23 is in the automatic position, automatic control is disabled, and in this case as well, the tail wheel can be adjusted using the manual switch 24.

Figure 4 shows the rotary clutch operation structure, and the rotary clutch 2 installed inside the transmission case 2.
The operating arm 28 of No. 7 and the rotary clutch lever 26 are linked via a release wire 29 and a spring 30, and the rotary clutch 27
is always biased in the clutch disengaging direction by a spring 31, and by swinging the clutch lever 26 past its dead center, it can be switched to and held in the clutch engaged position (a) and disengaged position (b). ing.

A solenoid 32 is linked to the operating arm 28 for forcibly operating the arm 28 toward the clutch disengagement side when energized.

The electrical circuit for driving the solenoid 32 is shown in FIG. In the figure, 33 is a setting device;
34 is a comparison circuit, and 35 is a switching circuit for driving a solenoid. Circuit 35 is turned on and solenoid 32
is energized and the rotary clutch 27 is automatically disengaged. Therefore, when one stroke of plowing is completed and the handle 6 is lifted significantly to pull the rotary tiller 8 above the ground in order to change direction of the machine at the edge of a ridge, the rotary drive automatically stops. . Incidentally, when the rotary clutch 27 is disengaged by energizing the solenoid 32, the operation of the switching circuits 18 and 20 for controlling the tail wheel elevation is controlled.

[Another example]

As the inclination sensor 14, it is also possible to use a type that uses a pair of switches for forward and reverse operation to detect deviation from a set angle range.

[Brief explanation of drawings]

The drawings show an embodiment of the walk-behind cultivator according to the present invention, in which Fig. 1 is an electric circuit diagram for elevating the tail wheel, Fig. 2 is an overall side view of the cultivator, and Fig. 3 is a side view of the tail wheel elevating mechanism. 4 are configuration diagrams of the rotary clutch operating mechanism. 5... Battery, 9... Tail wheel, 13... Electric motor, 14... Sensor, 27... Rotary clutch.

Claims (1)

[Claims] 1. A tail wheel automatic elevation control mechanism that operates the electric motor 13 for elevating the tail wheel 9 based on the detection result of the sensor 14 that detects the longitudinal inclination of the aircraft to stably maintain the longitudinal inclination angle of the aircraft within a set range; The control mechanism is configured to be inoperable when the rotary clutch 27 is disengaged, and the control mechanism is configured to be inoperable when the rotary clutch 27 is disengaged.
A walk-behind cultivator equipped with a manual switch 24 for directly operating the power switch 3 in forward and reverse directions.