JP2000300707A - Golf cart - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the wrong operation of a steering by the influence of the magnetic field of a brake motor or the like to prevent the meandering by setting the pulse width modulation frequency for controlling the brake motor or the like so that its integer-multiplied frequency is largely different, compared with the frequency of a guidepath wire. SOLUTION: In a passenger golf cart, induction currents carried in loop lines buried along a traveling path are detected by lateral induction sensors 10 in automatic steering mode, and a microcomputer 2 performs a steering control so that a guidepath wire is regularly located in the center of the induction sensors by rotating a steering motor 12 to the right when a left slippage is detected and rotating the steering motor 12 to the left when a right slippage is detected. At this time, the pulse width for driving the steering motor 12 is duty controlled by PWM (pulse width modulation) method according to the slippage. The integer-multiplied frequency of the PWM frequency for controlling the steering motor 12 or the like is set sufficiently large than the guidepath wire frequency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf cart capable of automatic steering along a guide line of a predetermined traveling path.

[0002]

2. Description of the Related Art Various types of golf carts have been conventionally provided for golf courses. For example, a hand-held type using a caddy, a non-riding type or a riding type using an electric motor or an engine as a driving force are frequently used.

FIG. 1 shows four to five persons developed by the present applicant.
1 shows an external view of a passenger-type engine-type riding golf cart. This riding golf cart is of an engine-driven type having a guide / manual switching means, and is designed to allow a person to ride on each of the front and rear sides. A golf bag can be loaded at the rear, and a roof for sunshade and rain can be installed at the top.

The control system of the riding golf cart generally includes a microcomputer of a control box, an operation unit, a steering unit, a sensor unit, a power supply unit, an engine unit, a parking unit, and a main brake unit.

To automatically steer a riding golf cart having such a configuration, an automatic steering mode is set by setting an automatic operation switching lever to "automatic". At that time, the induction current flowing through the induction wire buried along the cart path (running road) is detected by the left and right induction wire detection sensors, or the magnet is read, and the automatic operation, automatic increase / deceleration, and automatic stop are performed. While traveling on the cart road. Then, the user can start and stop at an arbitrary place using the remote control or the start / stop button. In addition, when a danger is detected by various safety devices, an emergency stop is performed.

Next, when performing the manual operation, when the automatic operation switching lever is set to "manual", a manual driving mode is set, and
As with a normal passenger cart, the player can operate forward and backward by operating the steering wheel (steering wheel) and operating the accelerator and brakes.

In these riding golf carts, when automatic steering is performed, the operation is controlled by controlling the rotation of a brake motor, an accelerator motor, a steering motor, and the like. In this case, the rotation of the motor is controlled by pulse width modulation (hereinafter referred to as PWM), and the rotation speed and the torque are determined by the frequency and the duty.

[0008]

In these riding golf carts, in the case of automatic steering, the signals detected by the left and right guide line detection sensors on the guide lines provided on the traveling path are converted into an amplifier of a signal detection circuit. After that, the signal is converted into a DC level corresponding to the left and right by a DC level converter. At this time,
If there is a motor magnetic field such as a brake motor near the sensor,
The guide line detection sensor detects the magnetic field of the motor at the same time as the guide line magnetic field.

At this time, when the frequency of the induction wire current is the same as the integral multiple of the PWM frequency for motor control, the DC level is not affected, but if there is any deviation, the frequency is reduced to the DC level. Appears as a swell. As a result, when the golf cart travels on a straight line of the travel path, if it is affected by the magnetic field of the motor, the golf cart has an illusion of meandering on the guide line due to the undulation.

[0010] Then, the golf cart operates the steering wheel finely to the left and right in accordance with the undulation so as to compensate for it, so that the golf cart actually performs a meandering operation. This is a very unpleasant sensation for the driver and the passenger, and it causes a squeaking noise of the vehicle body and promotes the wear of the tire, which is disadvantageous.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a golf cart which prevents erroneous steering operation due to the influence of a magnetic field of a brake motor, an accelerator motor, a steering motor or the like, thereby preventing a meandering operation.

[0012]

According to a first aspect of the present invention, there is provided a golf cart configured to be capable of automatic steering along a guide line of a predetermined traveling path. The frequency obtained by multiplying the pulse width modulation frequency for controlling the brake motor, the accelerator motor, the steering motor, and the like by an integer is set to be a frequency farther apart than the frequency of the induction wire.

The golf cart according to claim 2 of the present invention is
In a golf cart configured to be capable of automatic steering along a guide line of a predetermined traveling path, a frequency obtained by multiplying the pulse width modulation frequency for controlling a brake motor, an accelerator motor, a steering motor, and the like by an integer thereof is a guide line. The frequency was set to be 30 Hz or more, and the frequency was set to be farther apart than the frequency of the above.

A golf cart according to a third aspect of the present invention is
In a golf cart configured to be capable of automatic steering along a guide line of a predetermined traveling path, a frequency obtained by multiplying the pulse width modulation frequency for controlling a brake motor, an accelerator motor, a steering motor, and the like by an integer thereof is a guide line. The frequency was set to be the same as that of the above.

In this way, the frequency of the integral multiple of the PWM frequency for controlling the brake motor, the accelerator motor, the steering motor and the like is made sufficiently larger than the induction line current frequency or the same as the induction line frequency. Since the amplitude of the undulation can be reduced, there is no effect on the steering operation and the meandering operation of the golf cart does not occur, so that smooth driving can be ensured, the squealing noise of the vehicle body is prevented, and the tire Wear can be reduced.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 2 and 3 show system diagrams of a control system of an engine-type riding golf cart to which the present invention is applied.
FIG. 2 and FIG. 3 are divided into left and right parts with the microcomputer 2 of the control box 1 as a center, and the combined figure is the entire control system diagram. The control system roughly includes the microcomputer 2 of the control box 1, the operation unit 3, the steering unit 4, the sensor unit 5, the power supply unit 6, the engine unit 7,
It comprises a parking section 8 and a main brake section 9.

The control system of the steering unit 4 includes an inductive sensor 10 and a steering driver 1 as well as a steering wheel.
1, a steering motor 12, a torque sensor 13 linked to a steering wheel, not shown, but a pre-processing circuit for a detection signal of an inductive sensor, and left and right responding to left or right rotation of the steering wheel Means for detecting a steering operation amount such as an operation detection switch or a volume is disposed.

FIG. 4 shows an embodiment of a pre-processing circuit for a detection signal of the inductive sensor 10. In the figure, the inductive sensor 10
Right, left, and center guidance sensors 10a, 10b, and 10c are provided, and the respective guidance sensors 10a, 10b, and 10c are provided.
The detection signal of c is supplied to DC level conversion circuits 15a, 15b, and 15c that convert a specific frequency signal into a DC signal via amplification circuits 14a, 14b, and 14c.

The outputs of the DC level conversion circuits 15a and 15b corresponding to the left and right induction detection signals are output from the level synthesis conversion circuit 1.
6, the signals are converted into the sign and the absolute value of both signals, and then input to the microcomputer 2. The center guidance sensor 10c is for determining the presence or absence of a guidance line, and is not directly related to the present invention, and thus description thereof is omitted here.

When the riding golf cart having such a configuration is to be automatically steered, the automatic steering mode is set by setting the automatic operation switching lever to "automatic". At this time, an induction current flowing through a loop line buried along the traveling path is detected as an induction signal by the left and right induction sensors 10 and transmitted to the microcomputer 2 via the amplification circuit 14, the DC level circuit 15, and the level synthesis conversion circuit 16. Is entered.

When a left shift is detected, the microcomputer 2 rotates the steering motor 12 rightward via the steering driver 11, and when a right shift is detected, the microcomputer 2 rotates the steering motor 12 leftward so that the guide line is always guided. Perform steering control so that it is at the center of the sensor. At this time, the pulse width for driving the steering motor 12 is duty-controlled by a PWM (Pulse Width Modulation) method in accordance with the amount of deviation, thereby controlling the rotational force of the motor and smoothing the steering movement.

A torque sensor 13 for detecting a leftward or rightward operation direction and an operation force of the steering wheel is mounted in conjunction with the steering wheel, and detects a driving voltage applied to the steering motor 12 by the torque sensor. 13 or a voltage corresponding to the output, or PWM (pulse width modulation)
In this case, the voltage can be determined by the duty corresponding to the output of the torque sensor 13. The relationship between the output and the amount of rotation of the steering motor 12 is linear.

Therefore, the operating force of the steering wheel is detected by the torque sensor 13, and the steering motor 12 is rotated to the right via the microcomputer 2 when the operation is performed in the right direction. At the time of a leftward operation, the steering motor 12 is rotated to the left via the microcomputer 2.

As described above, the vehicle travels on the traveling path while performing automatic control, automatic increase / decrease, and automatic stop according to the command from the microcomputer 2. It is also possible to start and stop at an arbitrary place by operating the remote control or the start / stop button. Also,
If a danger is detected by various safety devices such as cart guard detection means, an emergency stop is performed.

In these riding golf carts, when automatic steering is performed, the operation is controlled by controlling the rotation of a brake motor, an accelerator motor, a steering motor 12, and the like. In this case, the rotation of the motor is controlled by pulse width modulation (hereinafter referred to as PWM), and the rotation speed and the torque are determined by the frequency and the duty.

On the other hand, the signals detected by the left and right guide line detection sensors on the guide lines disposed on the traveling path are amplified by the amplifiers of the signal detection circuit, and then converted to DC levels corresponding to the left and right by the DC level converter. Is converted. At this time, if there is a motor magnetic field of a brake motor or the like near the sensor, the induction wire detection sensor will detect the motor magnetic field at the same time as the induction wire magnetic field.

At this time, when the frequency of the induction wire current is the same as the integer multiple of the PWM frequency for motor control, the DC level is not affected, but if there is any deviation, the frequency is reduced to the DC level. Appears as a swell. An example will be described with reference to FIG.

For example, if the induction wire current frequency is 1500 Hz
And the PWM frequency for brake motor control is 250
In the case of control at Hz, 250 Hz × 6 = 1500 Hz, so that complete tuning can be achieved and no DC level is generated. However, as shown in FIG.
In some cases, such as the case where the frequency is divided from the oscillator to make it soft, a deviation of about 250 Hz ± 1 Hz occurs due to the variation of the oscillator. In this case, a swell of 1 Hz × 6 = 6 Hz, that is, ± 6 Hz, occurs at the DC level.

From the beginning, the PWM frequency for motor control is set to 2
Similarly, when the frequency is set to 51 Hz, a swell of 6 Hz is generated at the DC level. As a result, when the golf cart travels on a straight line of the travel path, if it is affected by the magnetic field of the motor, the golf cart has an illusion of meandering on the guide line due to the undulation.

Next, the induction line current frequency is 1500 Hz, and the PWM frequency for controlling the brake motor is 250.
When controlling at 2 Hz, 250.2 Hz × 6 = 150
1.2 Hz. In this case, as shown in FIG. 2 Hz × 6 = 1.2 Hz, that is, a swell of 1.2 Hz occurs at the DC level. Since the amplitude of the undulation is inversely proportional to the frequency, FIG.
(B) has a greater swell amplitude.

As a result, the golf cart operates the steering wheel finely to the left and right according to the undulation so as to compensate for this, so that the golf cart actually performs a meandering operation. The meandering operation is affected as the amplitude of the undulation increases, that is, as the frequency of an integral multiple of the PWM frequency for motor control is smaller than the induction wire current frequency. This is a very unpleasant sensation for drivers and passengers,
Induces the squeaking noise of the car body and also increases the tire wear.

Therefore, in the present invention, the frequency of an integral multiple of the PWM frequency for motor control is set to be sufficiently larger than the induction line current frequency, so that the amplitude of the undulation is reduced to prevent the meandering operation. As a result of the experiment, the induction wire current frequency was 1500 Hz, and the PWM
It has been found that when the frequency is controlled at 255 Hz or more, that is, when a frequency that is an integral multiple of the PWM frequency for motor control is separated by 30 Hz or more from the induction wire current frequency, the meandering operation due to undulation hardly occurs.

FIG. 5C shows that the induction line current frequency is 15
00 Hz, and shows a case where the PWM frequency for controlling the brake motor is controlled at 270 Hz. At this time, 20 ×
6 = 120 Hz, that is, a swell of 120 Hz, so that the influence on the steering operation can be prevented. As a result, the meandering operation of the golf cart does not occur,
Smooth driving can be secured, squeaky noise of the car body is prevented,
Tire wear can be reduced.

Of course, the induction wire current frequency is 1500 Hz, and the PWM frequency for controlling the brake motor is 250 H
In the case of control with z, 250 Hz x 6 = 1500 Hz, complete tuning is achieved, and no DC level is generated.
Since there is no influence on the steering operation and the meandering operation of the golf cart does not occur, smooth driving can be ensured, squeak noise of the vehicle body can be prevented, and tire wear can be reduced.

In the above description, the PWM frequency for controlling the brake motor has been described for convenience, but the same applies to the pulse width modulation frequency for controlling the accelerator motor, the steering motor and the like.

In the present embodiment, the frequency of the pulse modulation frequency for controlling the motor is multiplied by an integer and is equal to or larger than the frequency of the induction wire. Sensor 10
By providing a shield device such as a shield around the antenna, or by providing the directivity of reception on the guide wire side, a similar effect can be obtained without detecting a magnetic field of a control motor or the like.

[0037]

As described above, in the golf cart according to the present invention, the frequency obtained by multiplying the pulse width modulation frequency for controlling the brake motor, the accelerator motor, the steering motor, etc. by an integer thereof is higher than the frequency of the induction wire. By setting the frequency to be farther apart or the same as the frequency of the guide line, there is no effect on the steering operation, and the meandering operation of the golf cart does not occur. Driving can be ensured, squeaking noise of the vehicle body can be prevented, and tire wear can be reduced.

[Brief description of the drawings]

FIG. 1 is an external view of a riding golf cart.

FIG. 2 is a control system diagram of a riding golf cart.

FIG. 3 is a control system diagram of a riding golf cart.

FIG. 4 is a pre-processing circuit for a detection signal of an inductive sensor.

FIG. 5 is a waveform of a swell signal superimposed on an inductive sensor signal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Control box 2 Microcomputer 3 Operation part 4 Steering part 5 Sensor part 6 Power supply part 7 Engine part 8 Parking part 9 Main brake part 10 Induction sensor 11 Steering driver 12 Steering motor 13 Torque sensor 14 Amplification circuit 15 DC level conversion circuit 16 Level synthesis Conversion circuit

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Tomoaki Uenishi 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Tomohiro Yamada 2-chome Keihanhondori, Moriguchi-shi, Osaka No. 5-5 Sanyo Electric Co., Ltd. (72) Inventor Kazuhiro Matsuoka 2-5-5 Keihanhondori, Moriguchi-shi, Osaka F-term in Sanyo Electric Co., Ltd. 3D032 CC02 CC20 CC26 DA03 DA15 DA21 DA76 DA88 DD10 EA01 EC22 EC27 FF01 GG20 5H301 AA03 AA09 BB13 CC03 CC08 DD06 DD17 EE05 GG06 GG29 HH01 MM05 MM09

Claims (3)

[Claims] In a golf cart configured to be capable of automatic steering along a guide line of a predetermined traveling path, a pulse width modulation frequency for controlling a brake motor, an accelerator motor, a steering motor, and the like is multiplied by an integer thereof. A golf cart, wherein the frequency is set so as to be farther apart than the frequency of the guide wire. 2. The golf cart according to claim 1, wherein the separated frequency is 30 Hz or more. 3. A golf cart configured to be capable of automatic steering along a guide line on a predetermined traveling path, wherein a pulse width modulation frequency for controlling a brake motor, an accelerator motor, a steering motor, and the like is multiplied by an integer thereof. A golf cart wherein the frequency is set to be the same as the frequency of the guide wire.