JP2819586B2 - Alarm system for electric vehicles - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alarm device for an electric vehicle, and more particularly to an alarm device for an electric vehicle for alarming the surroundings of the running or approach of the electric vehicle. It is.

[Conventional technology]

3 and 4 show a conventional example. FIG. 3 is a block diagram showing a schematic configuration of the electric vehicle and a connection of an alarm device to the electric vehicle.

In FIG. 3, a battery 11 is a main switch.
When the switch 12 is turned on, power is supplied to each part of the electric vehicle, and an ignition power supply is supplied to an engine (not shown) to make it operate and to start the engine.

The stabilized power supply unit 13 is supplied with power from the battery 11, outputs a constant voltage Vcc, and supplies this to each unit. When operated, the accelerator 14 that controls the running of the electric vehicle generates an accelerator voltage having a magnitude corresponding to the degree of opening. The energization control circuit unit 15 controls the energization current from the battery 11 in the motor drive unit 16 according to the accelerator voltage. The motor 17 generates a rotational force in accordance with the current supplied from the motor drive unit 16, and thereby the electric vehicle is driven.

The alarm synthesizing unit 18 generates an alarm signal when the ground is given by operating the alarm switch 19. The warning signal may be a simple audible signal or a signal based on a synthesized voice. The speaker amplifier 20 is connected to the alarm switch 19
In response to the operation, the alarm signal generated by the alarm synthesizing unit 18 is amplified and output. The speaker 22 emits a warning signal as sound according to the output signal of the speaker amplifier 20, and generates a warning. The alarm synthesizing section 18 and the speaker amplifier 20 constitute an alarm section 21, and the speaker 22 constitutes an alarm generating section.

The control (on or off) of the alarm unit 21 in the electric vehicle as shown in FIG. 3 has been conventionally performed by various alarm generation factors as shown in the following (A) and (B).

(A). Manual operation (B). Automatic operation Accelerator voltage on detection Main switch interlocking Motor rotation pulse detection Current detection Others (seat switch etc.) Here, in the case of the manual operation shown in (A), for example, by manually operating the alarm switch 19, the alarm unit
21 is activated to generate an alarm.

In the case of the automatic operation shown in (B), when any of the various factors as described below occurs, an alarm control signal is given to the alarm unit 21 to put the alarm unit 21 into an operating state and set an alarm. Occurs.

FIG. 4 shows an example of a conventional alarm control signal generation circuit (in the case of the above (B)).

In FIG. 4, reference numeral 31 denotes a rotation pulse generator, which is coupled to the motor 17 and is generated per unit number of pulse unit times that changes according to the rotation speed of the motor 17. A differentiating circuit 32 including a capacitor C1 and a resistor R1 differentiates the pulse generated by the rotation pulse generator 31 to generate a differentiated pulse. The amplifier 33 has an operational amplifier IC1 and amplifies a pulse generated by the differentiating circuit 32 to generate an output pulse. An integrating circuit 34 including a resistor R2 and a capacitor C2 integrates an output pulse of the amplifier 33. The comparator 35 has an operational amplifier IC2, generates an output when the integrated output voltage of the integration circuit 34 exceeds a certain threshold, turns on the transistor 36, and grounds the alarm unit 21. As a result, an alarm control signal is given, and an alarm signal is generated from the alarm unit 21.

[Problems to be Solved by the Invention] Among the various alarm factors (A) and (B) described above, each factor when an alarm is automatically generated as shown in (B) has the following problems. .

Is the simplest method, but if an alarm device is to be retrofitted, it is necessary to branch off the accelerator voltage and the electric vehicle needs to be modified. .

In the method based on the interlocking of the main switch shown in (1), an alarm is always generated while the main switch is turned on, that is, while the electric vehicle is operating, and an unknown alarm is generated.

In the method based on the detection of the motor rotation pulse shown in (1), it is necessary to take in the motor rotation pulse, and it is necessary to newly provide a circuit part for this as exemplified in FIG.

In the method based on current detection (for example, motor current) shown in (1), an additional circuit for current detection is newly required.

In the method using the seat switch described in (1), it is necessary to newly provide a switch (seat switch) for detecting the occupant's seat on the seat of the electric vehicle, which is expensive.

[Object of the invention]

The present invention is to solve such a problem of the related art, and detects an increase in a ripple of a battery discharge current at the time of motor rotation in an alarm unit, forms an alarm control signal, and uses the alarm control signal. It is an object of the present invention to provide an alarm device for an electric vehicle which can be easily and inexpensively mounted even in the case of retrofitting.

[Means for solving the problem]

The present invention relates to an alarm device for alarming the surroundings of the running or approach of an electric vehicle, which uses a battery for driving a motor for running as a power source, activates when an alarm control signal is received, and issues an alarm. An alarm unit, a ripple detecting means for detecting a ripple of the output voltage of the battery generated by driving the motor and generating a detection pulse, and generating a smoothed output by integrating the detection pulse of the ripple detecting means And an alarm control signal generating means for detecting when the output of the integrating means exceeds a certain reference value and generating the alarm control signal. This aims to achieve the above-mentioned object.

(Example of the invention)

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

The embodiment shown in FIG. 1 is operated by a battery 11 for supplying a current to a driving motor 17, and has an alarm unit 21 which is activated when an alarm control signal is received to generate an alarm. A ripple detecting means 1 for detecting a ripple in the voltage of the battery 11 and generating a detection pulse.
And an integrating means 2 for integrating the detection pulse of the ripple detecting means 1 to generate a smoothed output. Further, there is provided an alarm control signal generating means 3 for detecting when the output of the integrating means 2 exceeds a certain reference value and generating an alarm control signal.

More specifically, the ripple detecting means 1 includes a voltage divider 24 for dividing the output voltage of the battery 11 and a voltage divider 24.
It comprises an amplifier 25 that receives a part of the voltage divided by the above and amplifies the ripple of the battery voltage, and a differentiating circuit 26 that forms a pulse signal based on the output signal of the amplifier 25.

Here, the voltage divider 24 includes resistors R3 and R4, and when the main switch 12 is on, divides the battery voltage and generates a detection signal at point a. The amplifier 25 has the operational amplifier IC3 and amplifies the signal at the point a. However, the other input of the operational amplifier IC3 is supplied with a constant voltage v _a slightly smaller than the signal at the point a. In the output signal of the amplifier 25, the ripple in the battery voltage appears to be enlarged. Further, the differentiating circuit 26 includes a capacitor C3 and a resistor R5. The differentiating circuit 26 differentiates the signal at point b to generate a signal consisting of a differentiated pulse at point c.

Further, the integrating means 2 includes a detecting circuit 27 for detecting the output signal (signal at point c) of the ripple detecting means 1 and an integrating circuit 28 for smoothing the signal output from the detecting circuit 27. I have.

The signal at point c is rectified by the diode D in the detection circuit 27 and smoothed by the capacitor C4. This gives d
A pulsating signal is generated at the point. The integrating circuit 28 includes a resistor R6 and a capacitor C5, and integrates the signal at point d to generate a signal smoothed to point e.

Additionally, the alarm control signal generating means 3, a comparator 29 for comparing inputs a signal point e sent from the integrating means 2 (signal in FIG. 2 e) and a constant reference voltage v _r, the comparator
A transistor 30 which is activated by the output of 29 and operates to output a predetermined alarm control signal to the alarm unit 21.

Here, the comparator 29 has an operational amplifier IC 4, when the signal point e exceeds a predetermined reference voltage v _r, to generate an output signal to a point f. The transistor 30 is turned on when an output signal is generated at the point f, and gives an alarm control signal by grounding the alarm unit 21.

Then, the alarm unit 21 generates an output when the alarm control signal is given from the transistor 30, and drives the speaker 22. As a result, the alarm signal generated by the alarm unit 21 is transmitted from the speaker 22 as an acoustic signal.

Other configurations are the same as those of the conventional example shown in FIG.

As described above, in the present embodiment, not only when the motor 17 is being driven by switching but also when the brush of the motor 17 and the commutator are "connected" or "disconnected" even when the accelerator is fully opened and the motor 17 is fully conductive. As a result, a pulsation occurs in the motor current, and this pulsation causes a pulsation (ripple) as shown in FIG. 2A in the terminal voltage of the battery 11.

In the circuit of FIG. 1, the ripple voltage is extracted from the battery voltage after the ripple component is amplified by the amplifier 25,
By smoothing the output and comparing it with a reference voltage,
The rotation of the motor 17 is detected.

When the motor 17 is not driven by switching, the ripple of the battery voltage is at the lowest level.In this state, the gain of the amplifier 25 is set so that an alarm control signal can be generated. When traveling, an alarm can be generated.

In this case, the signal e is a smoothing circuit 28 having a large time constant.
, The signal f gradually decreases even after the motor 17 is stopped, so that the signal f continues for a certain time Td after the motor 17 is stopped. Therefore, even when the electric vehicle is temporarily stopped, the alarm is not interrupted.

In addition, as a cause of the occurrence of the ripple in the battery voltage, there is a cause due to a reference oscillator or the like in a control unit of the electric vehicle main body (not shown) other than due to the rotation of the motor 17, but these are usually at a sufficiently low level. a reference voltage v _r of the comparator 28 can be removed the effect by setting appropriately.

〔The invention's effect〕

As described above, according to the present invention, since the alarm control signal for operating the alarm unit is detected by detecting the ripple of the battery voltage, the rotation of the motor is detected and the operation signal for the alarm unit is output. The alarm control signal generating circuit can be easily incorporated in the device, and a stabilizing power supply for the alarm control signal generating circuit is provided in the alarm device. It can be satisfied with only one connection line, and therefore, the installation of the alarm device is the easiest.If the time constant of the ripple detection voltage smoothing circuit in the alarm control signal generation circuit is increased to some extent, the temporary It is possible to provide an unprecedented excellent electric vehicle alarm device that can effectively prevent interruption of an alarm at the time of stopping.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of one embodiment of the present invention, FIG. 2 is a diagram showing signals of respective parts a to f in the circuit of FIG.
FIG. 4 to FIG. 4 each show a conventional example. DESCRIPTION OF SYMBOLS 1 ... Ripple detection means, 2 ... Integration means, 3 ... Alarm control signal generation means, 11 ... Battery, 13 ... Stabilized power supply section, 16 ... Motor drive section, 17 ... Motor, 21 ... Alarm section.

Claims (1)

(57) [Claims] 1. An alarm device for alarming the surroundings of the running or approach of an electric vehicle, wherein the alarm is activated by receiving an alarm control signal from a battery that drives a motor for driving. An alarm unit that emits, a ripple detection unit that detects a ripple of the output voltage of the battery generated by driving the motor and generates a detection pulse, and integrates a detection pulse of the ripple detection unit and outputs a smoothed output. And an alarm control signal generating means for detecting when the output of the integrating means exceeds a certain reference value and generating the alarm control signal. Alarm device.