JPH035717Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention provides an actuator for automatic control operation to a continuously variable transmission system for driving connected to a human operating tool, through a friction type transmission mechanism that allows operation by the human operating tool. Relating to interlocking work vehicles.

By providing a friction type transmission mechanism, such a work vehicle can perform a speed change operation using a manual operation tool when the actuator is stopped, or a preferential speed change operation using a manual operation tool when the actuator is under automatic control. However, there was a problem in that it was difficult to accurately stop the vehicle by operating the continuously variable transmission to a neutral state using a manual operating tool.

To explain in more detail, in order to stop the vehicle using the manual operating tool, it is necessary to reliably operate the manual operating tool to the neutral gear position, but this requires a large operating force that resists the frictional force of the friction transmission mechanism. While operating the manual control tool, the control tool can be quickly shifted to the neutral position.
It was certainly difficult to operate.

For this reason, the inventor of the present invention, as shown in FIG.
A swinging arm 25 equipped with a roller 24 that presses a cam plate 23 that swings together with the shift arm 7a toward the neutral shift side is provided, and a neutral shift pedal 30 is provided.
We have considered a means to operate the transmission to a neutral state when the pedal 30 is depressed, in conjunction with the swing arm 25 via the rod 31 and the spring 32, but in this case, simply stepping on the pedal 30 is sufficient. Although it is possible to shift gears to a neutral state, there are disadvantages in that special pedal operations are required to shift to a neutral state, and disadvantages in that manual operation requires a large operating force due to the friction type transmission mechanism D, so it is not practical. It was difficult.

The present invention has been made with the above-mentioned circumstances in mind, and its purpose is to improve operability through simple modification.

The working vehicle according to the present invention is characterized in that it is provided with a mechanism for biasing the transmission to return to the neutral transmission state, and a mechanism for disconnecting and disconnecting the transmission and the actuator. is as follows.

That is, since the link between the transmission and the actuator can be arbitrarily switched on and off, the friction transmission mechanism does not provide any resistance to the movement of the manual operating tool when the gear is changed manually. Furthermore, since a mechanism is provided for returning the transmission to the neutral gear shift state, the transmission can be automatically operated to the neutral gear shift state by simply releasing the operation on the manual operating tool.

Therefore, it becomes possible to easily shift gears using a manual operating tool with a small operating force, and to easily shift gears to a neutral state without requiring special operations. As a result, overall operability has been improved.

Hereinafter, embodiments of the present invention will be described based on the drawings.

As shown in FIG. 1, a drive case 2 that supports left and right front wheels 1 in a changeable direction, and a drive case 4 that supports left and right rear wheels 3 in a changeable direction, respectively.
A driving unit, which is attached to the main frame 5 and includes an engine E and a radiator 6, is mounted on the front side of the main frame, and a hydraulic continuously variable transmission 7, in which the engine output is transmitted to the shaft, is mounted on the rear side of the main frame. The output of the transmission 7 is transmitted to the front wheel drive case 2 by a shaft transmission mechanism and to the rear wheel drive case 4 by a gear transmission mechanism, and a forked steering handle 8. , and a driver's seat 9 are respectively provided, and a disk-type mower 10 is attached to the lower abdomen of the vehicle body so as to be movable up and down, thereby forming a lawn mowing vehicle.

As shown in FIG. 2, an interlocking arm 12 that swings integrally with the speed change pedal 11 is interlocked and connected to the swing type speed change arm 7a of the transmission device 7 via a push/pull rod 13, so that the speed change pedal 11 from the neutral shift position N to the forward forward side F, and the more the gear lever is depressed toward the rearward side R, the higher the backward speed.
Then, the electric motor M with a reduction gear serving as an actuator for automatic control operation is connected to the speed change arm 7a.
It is connected to a relay swinging arm 15 which is linked via a push-pull rod 14, using a multi-plate friction transmission mechanism D that allows operation by the pedal 11, so that it can be automatically operated as described later. Although the speed can be changed manually, it is also possible to manually change the speed using the pedal 11.

As shown in FIGS. 2 to 4, the friction transmission mechanism D includes a pair of friction plates 18 attached to the motor side output shaft 16 via balls 17 so as to rotate integrally therewith, and Those friction plates 1
A coned disc spring 19 is provided between the relay swing arms 8 and 8 to bias the relay swing arm 15 so as to clamp it therebetween.

A cam type operation shaft 20 is slidably attached to the output shaft 16 for switching between a state in which the ball 17 is engaged with the friction plate 18 and the output shaft 16 and a state in which the ball 17 is retracted from the output shaft 16. A mechanism C is formed by fitting the transmission device 7 and the electric motor M into and out of connection. However, reference numeral 21 in the figure is a swinging arm that slides and operates the operating shaft 20, and is connected to the operating shaft 20 by a pin and linked to the swinging lever 22 by wire.

In addition, as shown in FIG. 2, a swinging arm is provided with a cam plate 23 that swings integrally with the transmission arm 7a, and is equipped with a roller 24 that presses the cam plate 23 to operate the transmission 7a toward the neutral state. 25 is biased back toward the engagement side by a spring 26 to constitute a mechanism H that biases the transmission 7 back to the neutral gear shift state.

Next, the automatic control configuration will be explained.

A distance sensor S ₁ is provided to detect the traveling distance of the vehicle body based on the amount of rotation of the ground idle wheel 27, and
A direction sensor S ₂ is installed to detect the orientation of the vehicle body based on geomagnetism, and two tracing sensors S ₃ are installed to detect the boundary between uncut and mowed fields. They are distributed and arranged on both sides of the .

To configure the copying sensor _S3 , two inverted U-shaped sensor frames 28 each having a light-receiving element part and a light-emitting element part mounted at a distance in the width direction of the vehicle body are arranged side by side in the width direction of the vehicle body. and located at a height where light reception is blocked by the grass,
Thus, a state in which only one of the two sensor frames 28 on the inside of the vehicle body is shielded from light is determined to be a proper state.

In addition, potentiometers P1 are provided to detect the directions of the front and rear wheels 1 and ₃ separately, and a potentiometer _P2 is provided to detect the shift state of the transmission 7.
It is provided so as to be interlocked with the gears of the speed change arm 7a.

The detection signals of the sensors S ₁ , S ₂ , S ₃ and the potentiometers P ₁ , P ₂ are transmitted to a control device 29 constituted by a microcomputer.
A hydraulic cylinder 1 operates the front and rear wheels 1 and 3 separately according to command signals from the control device 29.
The control valves V ₁ and V ₃ of A and 3A and the electric motor M are automatically operated to perform reciprocating mowing work as shown in Fig. 7 and circular mowing work as shown in Fig. 8. It is configured.

To be more specific, the work will be carried out while moving along the boundary based on the detection information of the copying sensor _S3 , and if reciprocating mowing work is selected, the forward turning will be performed after one stroke is completed. You will have to make a 180 degree change of direction by making l ₁ and backward turning l _2. Also, if you have selected round mowing work, you will have to make a 90 degree direction change by making a backward turn l ₃ after completing one stroke. will be carried out.

In addition, when changing direction, select and use a sharp turn in which the front and rear wheels 1 and 3 each change direction in the opposite direction, or a slow turn in which only the front wheel 1 changes direction, and when entering the work area after changing direction, the front and rear wheels 1,3
It is arranged to use running in a state of parallel movement in which both are directed in the same direction.

Next, another example will be described.

In configuring the connection/disconnection mechanism C, in addition to incorporating it into the friction type transmission mechanism D, various configuration changes can be made.
The linkage/disconnection mechanism C may be operated using a drive device such as an electromagnetic solenoid, and in that case, the drive device is automatically operated based on information from a sensor that detects an obstacle in front of the vehicle body. It may be activated to automatically stop the vehicle body.

When configuring the return biasing mechanism H, various configuration changes can be made. Further, a lever can be used instead of the pedal 11, and these are collectively referred to as a human operating tool.

Further, the present invention can be applied to various types of work vehicles such as combine harvesters in addition to lawn mowing work vehicles.

[Brief explanation of the drawing]

The drawings show an embodiment of the working vehicle according to the present invention, in which Fig. 1 is a side view of the lawn mowing working vehicle, Fig. 2 is a schematic side view showing the operation configuration of the traveling speed change, and Fig. 3 is the installation of the friction type transmission mechanism. Fig. 4 is a cutaway side view of the same part, Fig. 5 is a schematic plan view showing the working state, Fig. 6 is a schematic diagram showing the specific configuration of automatic control,
FIG. 7 and FIG. 8 are schematic diagrams showing the running mode. FIG. 9 is a schematic side view of a comparative example. 7... Continuously variable transmission for traveling, 11... Human operating tool, C... Linkage/disconnection mechanism, D... Friction type transmission mechanism, H... Return biasing mechanism, M... Actuator.

Claims (1)

[Scope of utility model registration request] An actuator M for automatic control operation is connected to the continuously variable transmission device 7 for traveling to which the human operating tool 11 is linked.
The work vehicle is interlocked and connected via a friction transmission mechanism D that allows operation by the human operating tool 11, and is provided with a mechanism H for biasing the transmission 7 to return to a neutral gear shift state, and the transmission 7 and the actuator M.