JPS61143818A - Steering device of carrier car - Google Patents

Abstract

PURPOSE:To improve steering efficiency at the time of backward movement after manual operation by forming a steering wheel driving device for detecting the direction of a steering wheel and turning the steering wheels in a prescribed position. CONSTITUTION:Right and left rear wheels are pivotally fitted to an unmanned carrier car for golf links or the like and a steering wheel is set up on the center of the front side and the traveling of the unmanned carrier car is controlled by controlling the driving and steering of these wheels. The steering wheel driving device consists or right and left change-over switches 11, a steering circuit 12 consisting of an automatic traveling circuit and a manual traveling circuit, etc. The steering circuit 12 is turned to the automatic traveling circuit side when the switch 11 is connected to the traveling course detecting sensor 6 side, and turned to the manual traveling circuit side when connected to the steering wheel detecting sensor 7 side. In case of manual backward movement, the switch 11 is connected to the sensor 7 side, and when the steering wheel is turned by a fixed angle theta or more, a detecting signal is outputted from the sensor 7. The steering wheel is controlled so as to be held within the turning angle of + or -theta deg. on the basis of the detecting signal to move the carrier car in the backward direction easily and straight.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a steering device for steering a guided vehicle, for example, an automatic guided vehicle for a golf course, so as to proceed in a predetermined direction.

[Prior art]

At recent golf courses, automatic guided vehicles are often used to transport luggage such as golf bags or personnel such as players and caddies. This type of automated guided vehicle uses - the magnetic field from the induction loop wire buried in the running path in the lawn to the front left of the guided vehicle.

The vehicle is detected by two sensors installed on the right side, and the front wheels, which are the steered wheels, are steered so that the difference between the outputs of both sensors is below a certain value, thereby causing the vehicle to travel along the above-mentioned travel path. . The above-mentioned steering wheel is often a so-called swivel caster having a steering shaft in front of the axle.

In general, swivel casters automatically turn when the direction of travel is changed so that the axle is positioned behind the steering axis, but the swivel casters of the above-mentioned automatic guided vehicle ensure stability of steering and protect the sensor cable. etc., it is mounted so that it can turn by a predetermined limit turning angle, for example, 120°. Therefore, in this automatic guided vehicle, if you try to manually move it backwards, the above-mentioned swivel casters can only turn at the above-mentioned limit turning angle, and it remains turned at this angle, so that the axle is in front of the steering axis in the direction of travel. Otherwise, it will be located near it, and as a result, it will be extremely difficult to move it straight back.

Moreover, automatic guided vehicles for golf courses are often operated by women, and the difficulty of manually reversing them places a heavy burden on them.

[Purpose of the invention]

The present invention has been made in order to solve the problems with the conventional devices described above, and an object of the present invention is to provide a steering device for a guided vehicle that can significantly improve the steering performance especially when moving backward manually, and can greatly reduce the burden on the operator. It is an object.

[Structure of the invention]

The present invention provides a steering device for a guided vehicle, which is provided with a steering angle detection means for detecting the direction of a steered wheel, and a steering wheel drive device that receives an output from the detection means and turns a steering shaft in a predetermined direction. With this, for example, when manually moving straight backwards, the steering axis is made to be straight.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIGS. 1 to 4 are for explaining a steering device for a guided vehicle according to an embodiment of the present invention. In FIG. This is a vehicle body, and left and right rear wheels 2 are rotatably attached to the rear left and right sides of the vehicle body, and are driven by a rear wheel drive device (not shown). Further, a steering shaft 3 is attached to the center of the front part of the transport vehicle main body 1, and this steering wheel 3 has a steering shaft 3b in front of the axle 3a, and the steering wheel 3 has a steering shaft 3b in front of the axle 3a. These are tire-shaped so-called swivel casters, and are capable of turning within a limit turning angle of 120 degrees when viewed from a plane about the steering shaft 3b. In addition,
1a is a carrier for mounting the golf bang 1b, I
C is an operating handle, 1d is a brake lever, and 1e is an accessory case.

In FIG. 1 showing a schematic configuration of a steering wheel drive device for turning the steering wheel 3, 4 is a detected object made of magnetic metal attached to the steering shaft 3b so as to rotate together with the steering shaft 3b; Two sensor arms 5a extending forward are fixed to the detected object 4, and a sensor support plate 5b is installed between the arms 53. The left side of the bottom of 5b.

Left and right running path detection sensors 5a and 5b are attached to the right end, and both sensors 6a and 6b detect the strength of the magnetic field 17 (see Figure 4) from the induction loop wire 16 buried in the running path. Outputs a driving path detection signal according to the road condition.

Furthermore, left and right steering angle detection sensors 7a and 7b are attached to the rear of the detected object 4 of the conveyance vehicle main body 1 so as to face the left and right end portions of the rear surface of the detected object 4. The steering angle detection sensors 7a and 7b are high frequency oscillation type proximity switches,
When the detected object 4 approaches, that is, the steering wheel 3 is rotated at a predetermined angle θ.
When the vehicle turns more than this, the sensor on the approaching side turns on and outputs a detection signal.

A driven pulley 8a is fixed to the steering shaft 3b,
A steering motor 8 is attached to the rear of the driven pulley 8a of the carrier body 1, and the output torque of the motor is determined by the frictional force between the steering wheel 3 and the road surface, the grounding point of the steering wheel 3, and the steering shaft. This is sufficiently larger than the rotational force expressed by the product of the distance to 3b. The driving pulley 8b and the driven pulley 8a are fixed to the output shaft of the steering motor 8.
A transmission belt 8C is wound between the steering motor 8. With pulley ga, 8b and conduction belt 8C,
A steered wheel drive device 10 for steering the steered wheels 3 is configured.

In FIG. 3 showing the electric circuit of the steering wheel drive device 10, 5c and 7cm are amplifiers, 11a and llb are left and right selector switches, and 12 is a steering circuit consisting of an automatic running circuit and a manual running circuit. , this steering circuit 12 is switched to the automatic driving circuit side when the changeover switches lla and llb are connected to the driving path detection sensor side, and when the output of the left detection sensor 6a is larger than the right detection sensor 6b by a predetermined value or more, the left When the drive signal A is reversed, the right drive signal B is output, and when the switches lla and llb are connected to the steering shaft detection sensor side, it is switched to the manual travel circuit side, and the left or right detection sensor 7a, 7b, the right or left drive signal B or A is output. Also, 13
Drive switches a and 13b are turned on while the drive signals A and B are input; 14a and 14b are batteries; when the drive switches 13a and 13b are turned on, the steering motor 8 rotates to the left and right, respectively.

Next, the effects will be explained.

Here, FIG. 4 is for explaining the operation during automatic operation, and in this embodiment device, during automatic operation, the changeover switch l
la and llb are connected to the travel path detection sensor side shown in FIG. 3, and the steering circuit 12 is switched to the automatic travel circuit side. The magnetic field 17 of the induction loop line 16 is detected by the left and right running path detection sensors 6a and 5b, and the detection output is amplified by the amplification B6C and input to the steering circuit 12, so that the difference between the two human forces is equal to or less than a predetermined value. In this case, the circuit 12 does not output any signal, so the steering motor 8 does not rotate, the steering shaft 3 maintains its previous state, and the carrier continues to move forward (see FIG. 4(a)). ).

In addition, when the guided vehicle shifts to the right with respect to the guiding loop line 16 in the direction of travel, the output of the left running path detection sensor 6a becomes larger than the output of the right sensor 6b, and therefore the steering circuit 12 sends a left drive signal. A is output, which turns on the left drive switch 13a and rotates the steering motor 8 to the left.
When the steering wheel 3 is turned slightly to the left and the above-mentioned output difference becomes less than a predetermined value, the steering motor 8 stops, and the conveyance vehicle changes direction to the left at this turning angle (see Fig. 4).
(see bl).

If the guided vehicle shifts to the left, contrary to the above, the output of the right travel path detection sensor 6b increases, the right drive signal B is output, and the steering motor 8 rotates clockwise, thereby causing the guided vehicle to move toward the left. The vehicle then turns to the right (see (C) in the same figure), and in this way, the conveyance vehicle travels on the guide loop line 16.

Next, when manually reversing, first press the selector switch lla.
, llb are connected to the steering shaft detection sensor side, the steering circuit 12 is switched to the manual travel circuit side. and steering wheel 3
For example, when the steering wheel turns to the left by a certain angle θ or more, the distance between the left steering shaft detection sensor 7a and the detected object 4 becomes smaller than the detection distance of the sensor, and a detection signal is output from the left detection sensor 7a. The detection signal is input to the steering circuit 12, and the circuit 12 outputs the right drive signal B, and the drive switch 13b is turned on, the steering motor 8 rotates to the right, the steering shaft 3 turns to the right, and the above-mentioned turning occurs. When the angle is within θ degrees, the distance between the left detection sensor 7a and the detected object 4 becomes larger than the detection distance of the sensor, the steering motor 8 stops, and the steering wheel 3
is maintained in this state.

Also, contrary to the above, if the steered wheels 3 turn to the right by more than θ degrees,
The right steered wheel detection sensor 7b is turned on, the left drive signal A is output, and the steering motor 8 rotates to the left, thus keeping the steered wheel 3 within ±θ degrees.

As described above, in this embodiment, during manual driving, the steered wheels 3 are maintained within the turning angle of ±θ degrees, so the steered wheels 3 do not turn greatly, and even a weak woman can You can easily move it straight backwards. Also in this case,
Since the automatic steering mechanism conventionally provided in automatic guided vehicles for golf courses is used, only two steering angle detection sensors 7a are required.

7b and one detected object 4, the structure is simple and there is no problem in terms of cost.

In the above embodiment, the steering angle detection sensor 7a is used.

Although a high frequency oscillation type proximity switch is employed as 7b, this sensor may be any type of switch, such as a mechanical switch, a photoelectric switch, a magnetic switch, etc. Further, the detected object 4 does not necessarily need to be attached to the steering shaft 3b, but may be attached to a portion that is interlocked with the steering wheel 3, for example, the steering motor 8.

Further, in the above embodiment, an automatic guided vehicle for a golf course has been described, but the present invention is not limited to this, but is applicable to an automatic guided vehicle used for transporting workpieces in a production factory, for example.

Of course, it can also be used for manual transport vehicles.

〔Effect of the invention〕

As described above, the steering device for a guided vehicle according to the present invention includes the steering angle detection means and the steering shaft drive device that receives the detection output and turns the steered wheels to face a predetermined direction. This has the effect of significantly improving steering performance during manual driving, and has the effect of greatly reducing the burden on the driver.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of a steering device for a guided vehicle according to an embodiment of the present invention, Fig. 2 is a side view of an automatic guided vehicle for golf courses in which the above embodiment device is used, and Fig. 3 is a diagram of the above embodiment. The electric circuit diagram of FIG. 4(a) or 0) is a diagram for explaining the operation of the above embodiment. 3... Steering shaft, 3a... Axle, 3b... Steering shaft,
7a+7b...Steering angle detection sensor, 10...Steering wheel drive device, 16...Guidance loop line. Representative Patent Attorney Ken Hayase - Figure 4 (C)

Claims (3)

[Claims] (1) A device for steering a conveyance vehicle in a predetermined direction, comprising a steering angle detecting means for detecting the steering direction of a steering shaft, and receiving an output from the detecting means to direct the steered wheels in a predetermined direction. What is claimed is: 1. A steering device for a conveyance vehicle, comprising: a steering wheel drive device for turning the vehicle. (2) The above-mentioned guided vehicle is an automated guided vehicle for a golf course that runs along a guidance loop line buried in a lawn area when automatically running, and moves straight when running manually, and the above-mentioned steering axis is in front of the axle. 2. A steering device for a conveyance vehicle according to claim 1, wherein the steering device is a swivel caster having a steering shaft at one end thereof and capable of turning within a predetermined angle. (3) The steering device for a guided vehicle according to claim 2, wherein the steered wheel drive device turns the steered wheels so as to face the direction of the guide loop line during automatic travel.