JP2001025101A - Safety controller of electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively control the running and safety of an electric vehicle. SOLUTION: An electric vehicle is so constituted, that when the first operation after the power switch 1 is turned on is on an accelerator 2, a mode can be changed over to normal running mode and if when the first operation after the power switch is turned on is on a hand-push switch 3, the mode can be changed over to hand-push running mode. When normal running mode is established, the hand-push switch 3 is changed to an emergency stop switch 3. When the emergency stop switch 3 is operated, the accelerator 2 operation is defeated, and the electric vehicle is forcedly stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle such as an electric wheelchair, and more particularly to a safety control device for the electric vehicle.

[0002]

2. Description of the Related Art In this type of electric vehicle, particularly in an electric wheelchair, there is a technique in which a hand switch is provided to release an electromagnetic brake so that the vehicle can be driven by hand, for storage in a narrow space such as an entrance of an ordinary household. It is disclosed in JP-A-4-255402 and the like. There are also various techniques for urgently stopping an electric vehicle at the time of various troubles during traveling.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to effectively perform the above-described traveling control and safety control of an electric vehicle.

[0004]

When the first operation after the power switch 1 is turned on is the operation of the accelerator 2, the mode can be switched to the normal driving mode, and when the first operation is the operation of the hand switch 3, the mode can be switched to the manual driving mode. Hand switch 3 along with switching to the normal driving mode.
To the emergency stop switch 3, and the emergency stop switch 3
In operation, the electric vehicle safety control device is characterized in that the electric vehicle is forcibly stopped prior to the operation of the accelerator 2.

[0005]

When the vehicle runs normally, the vehicle is switched to the normal operation mode by operating the accelerator 2 first after the power switch 1 is turned on, so that the normal driving operation can be performed as in the prior art. When the hand switch 3 is operated for the first time after the power switch 1 is turned on, the mode is switched to the manual driving mode, the braking stop means of the electric vehicle is released, and the vehicle can be switched to the manual driving mode. When the mode is switched to the normal traveling mode, the hand switch 3 is switched to the emergency stop switch 3, and the emergency stop switch 3 is switched during traveling.
By operating, the emergency stop of the electric vehicle can be performed prior to the operation of the accelerator 2, which is safe. In addition, by using the hand switch 3 as an emergency stop switch, the number of switches is reduced to improve operability. be able to.

[0006]

FIG. 1 shows an electric wheelchair in which the present invention is applied to an electric wheelchair. The electric wheelchair has a three-wheel structure in which one front wheel 5 and a pair of left and right rear wheels 6 and 6 are mounted on a body frame 4. The front wheel 5 can be steered by operating the steering wheel 7. Reference numeral 8 denotes a rear cover, in which a driving member for a rear wheel 6 such as a motor 9 and a gear box is provided. Reference numeral 10 denotes a step, and reference numeral 11 denotes a chair, which is supported by support rods 12, 12. Reference numeral 13 denotes a controller case, which is attached to the vehicle body frame 4 below the step 10 and in which a controller for traveling control is provided. 14 is the handle 7
At the top is an operation box for mounting, a power switch 1, a speed change volume switch 15, a forward / reverse changeover switch 16,
A battery display meter 17 and the like are provided. The accelerator 2 is provided along the right grip 18 of the steering wheel 7, and is configured so that the traveling speed can be adjusted according to the degree of rotation of the accelerator 2. The hand switch 3 is an operation box 1
4 is provided on the right end side operation surface, and is provided at a position where it can be operated while holding the right grip 18 of the handle 7 and also holding the accelerator 2.

FIG. 3 is a block diagram showing the connection between the input means and the control means of the travel control controller. When the power switch 1 is turned on, the current of the battery 19 is supplied to the control circuit (a) and the drive circuit (b). It is configured so that it can be supplied. Reference numeral 2 denotes a speed command signal generator, which is specifically constituted by a variable resistor whose rotation is adjusted by the accelerator 2, and outputs the output voltage to a CPU 20 as a central processing unit.
Output to The output voltage is set to the stop command voltage at the neutral position where the accelerator is automatically restored when the accelerator 2 is released. The speed change volume 15 is for setting the maximum speed at the time of the maximum operation of the accelerator 2.

[0008] The voltage of the battery 19 is detected by a battery voltage detector 31 and input to the CPU 20 for arithmetic processing, and the remaining battery level is output and displayed on the battery display meter 17 comprising five LEDs. The motor 9 is connected to the battery 19 via a forward / reverse switching relay 21,
The front / rear switching relay 21 is connected to the CPU 20 by a forward command circuit 22 and a reverse command circuit 23.

The drive transistor 24 is driven by a drive pulse which receives a command signal from the above-mentioned speed command signal generator 2, performs arithmetic processing by the CPU 20 and outputs the same, and supplies a current from the battery 19 to the motor drive circuit 25. I do. The braking transistor 26 is also driven by a braking pulse output from the CPU 20 by processing the command signal of the speed command signal generator 2 and outputs a motor driving circuit 25 as a closed circuit to exert a power generation braking action. It is. Reference numeral 27 denotes an encoder which is a line of speed detecting means, and detects the number of rotations of the motor 9 or each of the rotating shafts, and C
Input to the PU 20 to calculate the running speed. Numeral 28 denotes an electromagnetic brake of negative operation, which releases braking by energization during running and applies a braking force to the motor shaft by spring force during stopping. Reference numeral 29 denotes a temperature sensor which measures the temperature in the vicinity of a control unit, especially the drive transistor 24, inputs the measured temperature to the CPU 20 via an A / D converter, and limits or stops the current supplied to the motor 9 when the temperature rises. 9 and control unit. The current detector 30 is provided in the motor drive circuit 25, detects a supply current to the motor 9, inputs the current to the CPU 20 via the A / D converter, and detects a load state.

Next, the operation will be described. When the first operation of the accelerator 2 is performed after the power switch 1 is turned on,
That is, when the command signal from the speed command signal generator 2 is input to the CPU 20 prior to the operation input signal of the hand switch 3, the mode is switched to the normal driving mode by the CPU 20, and the electromagnetic brake 28 is released. In response to the command signal from the speed command signal generator 2, a drive pulse and a braking pulse are output from the CPU 20, so that the vehicle can travel normally. In the normal traveling mode, the hand switch 3 is switched to the emergency stop switch 3. When a vehicle or a person suddenly jumps out while traveling by the operation of the accelerator 2, the hand switch 3 is located close to the accelerator 2 mounting side of the operation box 14. When the emergency stop switch 3 provided is operated, the CPU 20 outputs an emergency stop signal prior to the accelerator operation. That is, after performing the motor power generation braking by the output of the braking pulse, the electromagnetic brake 28 is actuated to stop the electric vehicle emergency.

Next, in order to switch the electric vehicle from the normal driving state to the manual driving mode, the power switch 1 is first turned off, the normal driving mode is reset, and then the power switch 1 is turned on again and the accelerator pedal 2 is turned on. If the hand switch 3 is operated before the operation, this operation signal is sent to the CPU 20.
And the mode is switched to the manual pushing mode. The hand-operated switch 3 is a non-holding switch. The electromagnetic brake 28 is released only while the switch is being operated. When the switch is released, the electromagnetic brake 28 returns by the spring force to maintain the braking action. Note that even if the hand switch 3 is released, the hand pressing mode is maintained until the power switch 1 is turned off. Therefore, the pilot can operate the hand-operated switch 3 as needed to perform the hand-driven traveling.

Further, even in the manual pushing mode, the traveling speed of the electric vehicle is detected by the encoder 27, and the manual pushing speed is equal to or less than a certain speed, specifically, 2.8 k.
If the speed is less than m / h, the braking pulse is reduced to reduce the load of the manual driving, and the manual driving speed is 3 km / h.
Above, the braking pulse is increased to suppress the speed.
If the hand-held traveling speed exceeds 4.5 km / h, it is determined that the vehicle is traveling abnormally, the braking pulse is set to the maximum amount, and the electromagnetic brake 28 is intermittently decelerated for a short time (about one second). Thereafter, an emergency stop control for operating the electromagnetic brake 28 is performed. The cause of such a high speed during manual driving is considered to be the case where the driver performs the manual driving while riding downhill, etc. Is safe.

Next, a description will be given of the safety control in the case where the hand-held traveling speed is not detected due to the failure of the encoder 27. If the vehicle speed is not detected for a fixed time, for example, 3 seconds while the electromagnetic brake 28 is released, the encoder 27, the power generation braking by the motor 9 and
After deceleration by the intermittent control of the electromagnetic brake 28, it is stopped. Further, even when the time during which the vehicle speed is not detected is 3 seconds or less, the regenerative current is not less than
For example, when 2 A or more is detected, emergency stop control is performed in the same manner as described above. In addition, as a safety control means of the manual driving when the encoder 27 is out of order, when the electromagnetic brake 28 is released, the traveling speed is detected by the encoder 27,
The regenerative current is always detected by the current detection circuit 30,
When a regenerative current equal to or more than a predetermined value, for example, 2 A or more, is detected, emergency stop may be performed by determining that the vehicle is traveling at high speed due to downhill traveling regardless of the detection value of the encoder 27.

In addition, instead of the regenerative current, the battery voltage before the manual driving is stored in the CPU 20 and compared with the voltage during the manual driving. The emergency stop of the electric vehicle may be performed based on the judgment.

[Brief description of the drawings]

FIG. 1 is an overall side view.

FIG. 2 is an overall plan view.

FIG. 3 is a block diagram showing a control circuit.

FIG. 4 is a flowchart showing control steps.

[Explanation of symbols]

 1. Power switch 2. Accelerator 3. Hand switch, emergency stop switch

Continued on the front page (72) Inventor Takato Kagawa 1-2-5, Kinuyama, Matsuyama-shi, Ehime F-term in Atex Corporation (reference) 5H115 PA09 PC06 PG06 PI16 PI29 PU02 PV03 PV23 QI03 QI07 QN03 TB10 TI02 TI05 TO05 TO12 TR04 TR07 TR19 TU02 TU05 TU08 TW10 TZ06 UB01 UB05 UB08 UB11 UI15

Claims (1)

[Claims] When the first operation after turning on the power switch (1) is the operation of the accelerator (2), the mode can be switched to the normal driving mode, and when the first operation is the operation of the hand switch (3), the mode can be switched to the manual driving mode. And the hand switch (3) is switched to the emergency stop switch (3) in accordance with the switching to the normal driving mode. When the emergency stop switch (3) is operated, the electric vehicle is prioritized over the operation of the accelerator (2). A safety control device for an electric vehicle, which is forcibly stopped.