JPH0669266B2 - Battery charge / discharge warning device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery charging / discharging warning device which detects a charging / discharging state of a battery and gives an alarm indication of overcharging or overdischarging.

(Prior Art) Conventionally, as a battery charging / discharging warning device used in an automobile or the like, for example, one shown in FIG. 6 is known (Japanese Patent Publication No. 59-10541).

In FIG. 6, reference numeral 1 is an alternator, which allows the battery 4 to be charged through the diode 2 and the resistor 3. A first current coil 5 is connected in parallel to a resistor 3 through which a charging / discharging current of a battery 4 flows via a resistor 6,
The current coil 5 is wound around the reed switch 7 and generates a magnetomotive force according to the charging / discharging current of the battery 4. The reed switch 7 is a fuse 8 and an ignition switch 9
Power is supplied from the battery 4 and / or the alternator 1 via the output of the reed switch 7 is connected to the base of the transistor 11 via the resistor 10, and the transistor 11 is connected to the alarm lamp 12 as a collector load. . Further, a second current coil 13 that differentially generates a magnetomotive force is wound around the reed switch 7, and the second current coil 13 is grounded to the secondary side of the ignition switch 9 via a resistor 14. A constant magnetomotive force is generated in a direction in which the magnetomotive force of the first current coil 7 is canceled by connecting a constant current to the first current coil 7.

The operating characteristics of such a charging / discharging warning device are as shown in FIG.

In Fig. 7, the horizontal axis is the charging current (right side) and the discharging current (left side).
On the vertical axis, the magnetomotive force generated by the charging / discharging current is taken to
The current-magnetomotive force characteristics of the second current coils 5 and 13 and the on / off operation of the reed switch 7 are shown.

First, the first current coil 5 has a current-magnetomotive force characteristic shown by a straight line I, and the second current coil 13 has a current-magnetic characteristic shown by a straight line II. It is designed to generate a constant magnetomotive force that exceeds. The reed switch 7 is given the current-magnetomotive force characteristic given by the straight line III, which is a combination of the two characteristics.

In contrast to the combined characteristic III, the reed switch 7 is in the off state within the range indicated by the hatched line, and is turned on when the magnetomotive force exceeds the range of the hatched line, and the transistor 11 is driven to turn on the alarm lamp 12.

Specifically, first, when the ignition switch 9 is turned on while the alternator 1 is stopped, in this case, the reed switch 7 receives a magnetomotive force generated only by the second current coil 13 and is turned on, and the alarm lamp 12 is turned on. Light. Subsequently, when the battery discharge to the starter motor is started by the engine start, the alarm lamp 12 is continuously lit in the initial stage where the discharge current is large, but when the engine is started, the power generation output from the alternator 1 is obtained. The reed switch 7 can be installed by keeping the charging current within the shaded area.
Turns off and the alarm lamp goes out.

Further, during the operation of the alternator 1, the reed switch 7 is kept in the off state and the alarm lamp 12 is off because the recharge switch 7 is in a charging state which is normally within the range of the hatched portion. On the other hand, when the battery is overcharged beyond the range of the shaded area or transitions to the discharging state, the reed switch 7 is turned on and the alarm lamp 12 is turned on to warn.

On the other hand, if the positive terminal of the battery 4 is disconnected,
When the reed switch 7 is turned on and the alarm lamp 12 is turned on because the magnetomotive force of only the second current coil 13 is returned, and when the plasma side terminal is disconnected and the earth side is grounded, for example, the composite characteristic III Then, the alarm lamp 12 comes to light up.

(Problems to be Solved by the Invention) However, in such a conventional battery charging / discharging warning device, the value of the magnetomotive force by the second current coil 13 for producing the combined characteristic III is shown in the characteristic II. As described above, since the value is set to the ON region value beyond the OFF region of the reed switch 7 shown by the shaded portion, the alarm lamp 12 is constantly turned on regardless of the discharge current in the discharge state of the battery, and The alarm lamp is turned on even when the charging current slightly flows as indicated by Δi. However, the battery 4 is not always in a charged state during traveling, and it is common to repeat charging / discharging depending on the operating state of an in-vehicle device such as an air conditioner or a change in engine rotation. As a result, the alarm lamp frequently blinks in response to repeated charging / discharging of the battery while traveling, and there is a problem that the original role of the charging / discharging warning cannot be fulfilled.

(Means for Solving Problems) The present invention has been made in view of such problems in the related art. Even if the battery is repeatedly charged and discharged during traveling, an erroneous alarm display is not displayed, and It is an object of the present invention to provide a battery charging / discharging warning device with high reliability that reliably warns of overcharge and overdischarge.

The current coil (15) generates a magnetomotive force according to the charging / discharging current of the battery (4), and when the magnetomotive force has a first value, a first reed switch (18) for switching between opening and closing is provided. A second reed switch (25) for switching between opening and closing when the second value is smaller than 1 is provided,
When the magnetomotive force based on the opening / closing of the first reed switch (18) is larger than the first value, or the second
When the magnetomotive force based on the opening / closing of the reed switch (25) is smaller than the second value, an alarm is displayed by the alarm display means (12), and based on the opening / closing operation of the second reed switch (25). The alarm display means (21)
The alarm display is delayed by the delay means (23, 24) for a predetermined time so that the alarm display is not displayed even if charging and discharging are repeated during traveling.

(Embodiment) FIG. 1 is a circuit diagram showing an embodiment of the present invention.

First, the configuration will be described. 1 is an alternator, and the output of the alternator 1 is connected to the positive side of the battery 4 via a resistor 16 so that the battery 4 can be charged by the power generation output of the alternator 1. The current coil 15 is connected to the resistor 16 through which the charging / discharging current of the battery 4 flows.
Are connected in parallel via a current limiting resistor 17, and the current coil 15 generates a magnetomotive force according to the charging / discharging current of the battery 4. The current coil 15 is wound around the first reed switch 18 and the second reed switch 25,
Each of the reed switches 18 and 25 receives the magnetomotive force of the current coil 15 due to the charging / discharging current and opens / closes.

Here, as the second reed switch 25, one having a high sensitivity is used with respect to the first reed switch 18. That is, the first reed switch 18 is turned on by receiving the magnetomotive force of the current coil 15 exceeding the predetermined range,
The second reed switch 25 is the first reed switch 18
When it receives the magnetomotive force of the current coil 15 which exceeds the range of the magnetomotive force smaller than the above, it turns on.

The first reed switch 18 is the ignition switch 9
Is connected to a secondary side of the resistor via a resistor 19 for limiting current, and a connection point between the resistor 19 and the first reed switch 18 is connected to the resistor 2
It is connected to the base of the transistor 20 via 1.
Further, the second reed switch 25 is connected to the emitter of the transistor 20 via the resistor 22. The transistor 20 is connected to a timer circuit including a series connection circuit of a resistor 23 and a capacitor 24 connected to the secondary side of the ignition switch 9, that is, a connection point of the resistor 23 and the capacitor 24, and the resistor 23 and the capacitor forming the timer circuit. Two
The connection point of 4 is further connected to the base of the transistor 26, which connects the alarm lamp 12 as a collector load.

Further, a relay coil 27 is connected between the secondary side of the ignition switch 9 and the L terminal of the alternator 1, and the relay contact 27a is closed by energizing the relay coil 27.
Is connected between the collector of the transistor 26 and the ground so that the alarm lamp 12 can be turned on by closing the relay contact 27a. Here, the L terminal of the alternator 1 is at the ground potential when the alternator 1 is stopped, so that when the ignition switch 9 is turned on when the alternator 1 is installed, the relay coil 27 is energized. Also, when the alternator 1 operates, a generated voltage appears at the L terminal,
By setting both ends of the relay coil 27 to the same potential, the power supply to the relay coil 27 is cut off.

Next, the operation of the embodiment of FIG. 1 will be described with reference to the operation characteristic diagram of FIG.

FIG. 2 shows the relationship between the charging / discharging current flowing in the current coil 15 in FIG. 1 and the magnetomotive force. The horizontal axis shows the charging current, the left side shows the discharging current, and the vertical axis shows the charging / discharging. The magnetomotive force generated in the current coil 15 by the current is taken, and the current magnetomotive force characteristic passing through the origin having a predetermined inclination indicated by the solid line is obtained.

Further, the upper and lower widths of the shaded area are the off-regions of the first reed switch 18 due to the magnetomotive force of the current coil 15, and the off-regions of the highly sensitive second reed switch 25 are formed inside thereof. Therefore, in the shaded area, the first reed switch 18 is off and the second reed switch 25 is on.

Further, points a to d on the characteristic straight line are singular points that give the magnetomotive force and the charging / discharging current of each off region, and the point e is the positive terminal of the battery 4 being disconnected as will be made clear later. It is the operating point when it is grounded.

The operation of the embodiment shown in FIG. 1 will be described in detail. First, when the ignition switch 9 is turned on while the alternator 1 is stopped, the current flowing from the battery 4 to the load is zero or very small. Coil 1
The operating point due to the magnetomotive force of No. 5 is between the origin 0 and point c, and since the magnetomotive force is small, the first and second reed switches 1
Both 8 and 25 are off.

However, since the power supply voltage from the battery 4 is supplied to the secondary side of the ignition switch 9 when the ignition switch 9 is turned on, the L terminal is in the grounded state when the alternator 1 is stopped.
Current flows to the relay contact 2 by energizing the relay coil 27.
The alarm lamp 12 is turned on when 7a is closed.

Next, assuming that the engine is started by turning the ignition switch 9 to the start position, the alternator 1 is activated by starting the engine, and a power generation voltage substantially equivalent to the battery voltage appears at the L terminal of the alternator 1 to cause the relay. The coil 27 is de-energized, the relay contact 27a is opened, and the alarm lamp 12 is turned off.

Further, when the charging / discharging current is small in the operating state of the alternator 1 and between the operating points b to c in FIG. 2, the magnetomotive force due to the current coil 15 is small, so that the first and second reed switches. Both 18 and 25 are in the off state, and the second reed switch 25 is in the off state because the emitter of the transistor 20 is floating due to the off state. When the transistor 20 is in the off state, the secondary switch of the ignition switch 9 is turned on. The capacitor 24 is charged from the side via the resistor 23, and when the charging voltage of the capacitor 24 reaches a constant voltage after a fixed time, the transistor 26 is turned on and the alarm lamp 12 is turned on.

However, when the alternator 1 is in an operating state during driving, the battery 4 operates at the operating points a to d in FIG.
The charging / discharging is repeated within the range of, and if the charging current increases from the region of operating points b to c to the region of operating points c to d, for example, the second reed switch 25
Since the magnetomotive force exceeding the OFF region of is generated in the current coil 15, the second reed switch 25 is turned on, and when the second reed switch 25 is turned on, the transistor 20 is activated to reset the discharge of the capacitor 24, and again. When returning to the operating points b to c, the capacitor 24 is charged again from the initial state, and as a result, the operating points b to c are charged.
As long as the time within the range is within the set time of the timer circuit composed of the resistor 23 and the capacitor 24, the alarm lamp 1
2 never lights up.

On the other hand, the discharge state of the operating points a to b, or the operating points c to d
The second reed switch 25 when in the charging state of
Turning on turns on the transistor 20 and pulls the base of the transistor 26 to the ground potential to bring it into a cutoff state, so that the alarm lamp 12 does not light.

Next, when the charging / discharging state becomes excessive, the first reed switch 18 is turned on by exceeding the operating point a or b in FIG. 2 to pull the base of the transistor 20 to the ground level and cut off the capacitor 24. After the discharge reset state of is released, the transistor 26 becomes the capacitor 2 after the set time of the timer circuit composed of the resistor 23 and the capacitor 24.
The power is turned on at the charging voltage of 4, the alarm lamp 12 is turned on, and the overcharge or overdischarge alarm is displayed.

Furthermore, if the positive terminal of the battery 4 is disconnected,
Since the magnetomotive force due to the current coil 15 disappears, both the first and second reed switches 18 and 25 are turned off, and the resistance 2
After the delay due to the set time of the timer circuit composed of 3 and the capacitor 24, the transistor 26 is turned on and the alarm lamp 12 is turned on. Further, when the cable detached from the positive terminal of the battery 4 has a ground potential, for example, when it comes into contact with the vehicle body, a short-circuit current flows in the current coil 15 to shift to, for example, the operating point e, and the first reed switch. When 18 is turned on, the alarm lamp 12 is similarly turned on and an alarm is displayed.

FIG. 3 is a circuit diagram showing another embodiment of the present invention. This embodiment is characterized in that another current coil 30 of the first reed switch 18 around which the current coil 15 is wound is wound around to generate a differential magnetomotive force.

That is, the first reed switch 18 and the second reed switch 25 are wound with the current coil 15 through which the charging / discharging current of the battery 4 flows, as shown in FIG. Is wound around a current coil 30 that generates a differential magnetomotive force, that is, a magnetomotive force that acts in a direction of canceling the magnetomotive force of the current coil 15, and this current coil 30 is connected to the secondary side of the ignition switch 9 via a resistor 31. And a ground, a constant current determined by the resistor 31 is flowed, and the magnetomotive force of the current coil 15 determined by the charge / discharge current and the constant magnetomotive force of the current coil 30 are differentially applied to the first reed switch 18. It is working.

The other structure is the same as that of the first embodiment.

By winding another current coil 30 that differentially generates a constant magnetomotive force with respect to the first reed switch in this way, the operating characteristics shown in FIG. The operating points a to d providing the switch off area move to the operating points a1 to d1 as shown by the imaginary line. As a result,
By adjusting the magnetomotive force of the current coil 30, it is possible to arbitrarily change the current value as the alarm operating point during charging and discharging.

In the above embodiment, when the magnetomotive force exceeds the set range, the first or second reed switch 18, 25
However, the reed switches 18, 25 may be turned off when the magnetomotive force exceeds a predetermined range. In this case, the reed switches 18, 25 are turned on.
P as a transistor 20, 26 controlled by 25
The NP type may be used.

(Effect of the Invention) As described above, according to the present invention, a magnetomotive force corresponding to a charging / discharging current of a battery is generated in a current coil, and when the magnetomotive force has a first value, the first lead that switches between opening and closing. A switch (18) is provided, and a second reed switch (25) is provided for switching between opening and closing when the magnetomotive force is a second value smaller than the first value, and when the magnetomotive force is larger than the first value. Causes the alarm display means (12) to display an alarm based on the opening and closing of the first reed switch, and when the magnetomotive force is smaller than the second value, the alarm display means (12) displays the alarm. Reed switch (25)
Since the alarm display of the alarm display means (12) based on the opening / closing operation of the battery is delayed by the delay means (23, 24) for a predetermined time, charging / discharging stop state of the battery, over-discharge, over-discharge, disconnection of the battery terminal, etc. It is possible to detect the charging / discharging state and display an alarm reliably, and even if charging / discharging is repeated during driving, the alarm display is frequently repeated during driving by the action of delay means such as a timer circuit. The battery warning is displayed reliably and reliably.

Furthermore, for the magnetomotive force of the current coil according to the charge / discharge current,
It is possible to easily change the alarm set value of the charging / discharging current by applying a magnetomotive force differentially to the other current coil, and to display an appropriate battery warning according to the battery load and vehicle type.

[Brief description of drawings]

1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is an operation characteristic diagram of the embodiment of FIG. 1, FIG. 3 is a circuit diagram showing another embodiment of the present invention, and FIG. FIG. 5 is an explanatory view of the winding state of the current coil with respect to the reed switch in FIG.
FIG. 6 is an operation characteristic diagram showing the operation characteristic of the embodiment of FIG. 3 in comparison with that of FIG. 1, and FIG. 6 is a circuit diagram showing a conventional example,
FIG. 7 is an operation characteristic diagram of a conventional example. 1: Alternator 4: Battery 9: Ignition switch 12: Alarm lamp 15,30: Current coil 16,17,19,21,22,23,31: Resistor 18: First reed switch 20,26: Transistor 24: Capacitor 25: Second reed switch 27: Relay coil 27a: Relay contact

Claims (2)

[Claims] 1. A battery (4), a current coil (15) for generating a magnetomotive force according to a charging / discharging current of the battery (4), and a magnetomotive force generated by the current coil (15) is first. First reed switch (18) that switches between open and close when the value is reached
And, when the magnetomotive force has a second value smaller than the first value,
A second reed switch (25) that switches between opening and closing; and when the magnetomotive force is larger than the first value based on the opening and closing operation of the first reed switch (18), or the opening and closing of the second reed switch. An alarm display means (12) for displaying an alarm when the magnetomotive force is smaller than the second value based on the operation, and an alarm display of the alarm display means (12) based on the opening / closing operation of the second reed switch are predetermined. And a delay means (23, 24) for delaying the time. 2. A battery charging / discharging warning according to claim 1, further comprising a second current coil (30) for varying the first value between a charging current and a discharging current. apparatus.