JPH0670450U - Power supply - Google Patents

Abstract

(57) [Summary] [Purpose] Protects computer devices and other electrical devices from abnormal phenomena caused by a drop in the liquid level of a storage battery, and prevents the occurrence of extreme abnormal phenomena. In a power supply device that supplies a charging current from a generator driven by an internal combustion engine to a storage battery, the storage battery is equipped with a level detector that detects the liquid level in two stages, and it is detected that the first stage has been reached. When an alarm is generated, the power generation output is stopped when the second stage is detected.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a power supply device including a storage battery and a generator. The present invention is suitable for use as a power supply device for automobiles. The present invention relates to a device that prevents an abnormally high voltage from being generated when a storage battery is overcharged.

[0002]

[Prior art]

 A power supply device for an automobile includes a storage battery and a generator driven by an internal combustion engine to supply a charging current to the storage battery. If the state where the charging current of the storage battery is larger than the consumption current continues for a long time, electrolysis of water occurs in the electrolytic solution in the storage battery, and the liquid level decreases. Even in such a state, if the charging current is further supplied, the terminal voltage may rise abnormally. This is a phenomenon in which the terminal voltage reaches a voltage that exceeds twice the rated value (for example, 24V) of the terminal voltage (for example, a value that exceeds 50V).

FIG. 5 shows such a voltage change of the storage battery. The voltage is maintained at 28 to 29 V when the liquid surface level of the electrolytic solution is normal. If a failure occurs, the voltage cannot be adjusted and the voltage rises to 34 to 38V. However, since the voltage generated at this level can absorb the electric power generated by the storage battery, it does not affect the electric devices. However, if it is assumed that the liquid level falls below the predetermined stairs at the time of B and the charging is continued in the state as it is, the voltage exceeds 50 V, and if the state is continued for several hours, the electric device may be damaged.

Conventionally, when the terminal voltage of the storage battery rises to a certain value (for example, about 110-120% of the rated voltage), the current in the field winding of the generator is adjusted to prevent the storage battery from being overcharged. Although a regulator device for automatic control is widely known, such a conventional regulator device cannot cope with an abnormal state in which the electrolyte in the storage battery is extremely insufficient as described above.

[0005]

[Problems to be solved by the device]

 In recent years, automobiles are equipped with computer devices for controlling internal combustion engines, controlling transmissions, controlling brakes, and the like, and these are driven by direct current using a storage battery mounted in the automobile as a power source. These computer devices are designed to operate normally even if the terminal voltage of the storage battery fluctuates to some extent according to the driving state of the vehicle, but in an abnormal state where the electrolyte in the storage battery is extremely insufficient. When this happens, even if the power supply is repaired, the computer may be destroyed beyond recovery.

An object of the present invention is to provide a device capable of protecting a computer device and other electric devices from such an extremely abnormal phenomenon and preventing such an extremely abnormal phenomenon. And

[0007]

[Means for Solving the Problems]

 The present invention relates to a power supply device comprising a storage battery and a generator driven by an internal combustion engine to supply a charging current to the storage battery, and a level detector for detecting the liquid level of the storage battery in two stages, and a level detector. An alarm circuit that generates a warning in the driver's cab by the detection output of the first stage of the detector, and the generator output by the detection output of the second stage whose liquid level is lower than the level of the detection output of the first stage. And a relay circuit that reduces the current to the field winding to a level at which the power generation output is substantially stopped.

It is preferable that the relay circuit is configured to cut off a current to the field winding by the detection output of the second stage.

[0009]

[Action]

 When the battery level drops to the first level, the driver is alerted to replenish the battery. In general, this alarm does not cause an abnormal condition by taking appropriate measures. Even if the alarm of the first stage is sent out, it is ignored and operation continues, and when the liquid level drops to the second stage, the current in the field winding of the generator is cut off or controlled to an extremely small level. And stop the power generation output. This condition makes it almost impossible to continue operation, but it is possible to prevent computer devices and other important electrical devices from being destroyed and becoming unrecoverable.

[0010]

【Example】

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

First Embodiment FIG. 1 is a block diagram showing a configuration of a first embodiment of the present invention, and FIG. 2 is a diagram explaining a configuration and a detection operation of a level detector in the first embodiment of the present invention. FIG. 3 is a diagram showing a mounting position of a level detector of a storage battery and a variation range of a liquid level in the first embodiment of the present invention.

The first embodiment of the present invention includes a control circuit 1, a storage battery 2, and a generator 3 that is driven by an internal combustion engine and supplies a charging current to the storage battery 2. Further, as a feature of the present invention, a storage battery is provided. Level detector 4 which detects the liquid level of No. 2 in two stages, the first stage and the second stage, and sends the detection output to the control circuit 1, and the liquid level L ₁ of the first stage of this level detector 4. Based on the control output from the control circuit 1 based on the detection output of the alarm circuit 5 that issues an alarm to the operator's cab, and the detection output of the _second level liquid level L ₂ lower than the _first level liquid level L ₁ A relay circuit 6 is provided which shuts off the current to the magnetic field winding 3a of the generator 3 by the control output from the control circuit 1 and stops the power generation output.

As shown in FIG. 2, the level detector 4 includes a cylindrical detector main body 4a having a predetermined length, and a detector main body 4a which is inserted through the detector main body 4a and changes in the liquid level. It is equipped with a magnetic material float 4b that moves up and down, and a float stopper 4c that is fixed to the bottom of the detector body to prevent the float 4b from coming off. Inside the detector body 4a, the float 4b is the first level liquid level. There is provided a first switch 4d which is closed when the position reaches the level L ₁ and a second switch 4e which is closed when the float 4b reaches the second level liquid level L ₂ .

As shown in FIG. 3, the level detector 4 thus configured is individually attached to each of the plurality of storage batteries 2 mounted on the vehicle by utilizing the liquid ports 2a.

Next, the operation of the first embodiment of the present invention thus constructed will be described.

As shown in FIGS. 2 and 3, when the liquid level decreases from the normal level L ₀ and reaches the _first level liquid level L ₁ , the position of the float 4 b of the level detector 4 is accordingly increased. Goes down, the first switch 4d is closed and a detection signal is sent to the control circuit 1. Receiving this detection signal, the control circuit 1 activates the alarm circuit 5 to turn on the alarm lamp, and prompts the driver to replenish the liquid in the storage battery 2.

When the liquid is replenished according to this alarm, the liquid level rises to a normal level, and the float 4b of the level detector 4 rises with the rise of the liquid level and moves away from the position of the first switch 4d. When the float 4b is separated, the first switch 4d is opened, and the control circuit 1 stops sending the alarm from the alarm circuit 5.

Normally, this alarm takes measures to avoid the abnormal condition, but despite the fact that the warning of the first stage is sent out, it is ignored and the operation is continued, during which the liquid level rises. When it drops and reaches the second-stage liquid level L ₂ , the float 4b descends to the position of the second switch 4e, the second switch 4e is closed, and the detection signal is sent to the control circuit 1. The control circuit 1 operates the relay circuit 6 by this detection signal to forcibly open the relay circuit 6 to interrupt the current to the field winding 3a of the generator 3 to stop the charging output to the storage battery 2 and The alarm circuit 5 is operated to turn off the alarm lamp. In this state, the operation cannot be continued, but since the storage battery 2 is not charged, the overvoltage is prevented from being generated, and the destruction of the computer device and other important electric devices due to the overvoltage is prevented.

When the storage battery 2 is replenished with liquid and the liquid level is restored to the normal level L ₀ , the float 4b moves away from the position of the second switch 4e, so that the second switch 4e is opened and the control circuit 1 Stops sending the alarm from the alarm circuit 5, stops the current supply to the relay circuit 6, and closes the battery to charge the storage battery 2.

Second Embodiment FIG. 4 is a block diagram showing the configuration of the second embodiment of the present invention.

In the second embodiment of the present invention, the relay circuit 6 in the first embodiment is provided with a resistor 6a connected in parallel with the open / close switch, and the other parts are the same as in the first embodiment. Is made.

In the case of the second embodiment, when the liquid level of the storage battery 2 drops to the first level liquid level L ₁ , the same operation as in the first embodiment is performed, but the liquid level of the storage battery 2 is Is reduced to the _second level liquid level L ₂ and the relay circuit 6 is opened, the charging current from the generator 3 is supplied to the storage battery 2 via the resistor 6a.

According to the second embodiment, the abnormal shortage of the charge of the storage battery 2 due to the complete stop of the charge is prevented, and the charge is early when the liquid level is returned to the normal level L _0. To be able to go to.

[0024]

[Effect of device]

 As described above, according to the present invention, the decrease in the liquid level of the storage battery is detected in two stages, and in the first stage where the level decrease is not so serious, an alarm is sent to prompt the replenishment of the liquid and complete In the second stage, which is considered to be abnormal, charging is stopped to prevent damage to the computer device and other important electrical devices due to high voltage.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a first embodiment of the present invention.

FIG. 2 is a diagram for explaining the configuration and detection operation of the level detector in the first embodiment of the present invention.

FIG. 3 is a diagram showing a mounting position of a level detector of a storage battery and a variation range of a liquid level in the first embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a second embodiment of the present invention.

FIG. 5 is a diagram showing an example of a voltage change of a storage battery.

[Explanation of symbols]

 1 Control Circuit 2 Storage Battery 2a Liquid Port 3 Generator 3a Field Winding 4 Level Detector 4a Detector Main Body 4b Float 4c Float Stopper 4d First Switch 4e Second Switch 5 Alarm Circuit 6 Relay Circuit 6a Resistor 7 Key Switch

Claims (2)

[Scope of utility model registration request] 1. A power supply device comprising a storage battery and a generator driven by an internal combustion engine and supplying a charging current to the storage battery, comprising: a level detector for detecting a liquid level of the storage battery in two stages; An alarm circuit that issues an alarm to the cab by the detection output of the first stage of the detector, and a detection output of the second stage whose liquid level is lower than the level at which the detection output of the first stage is sent out A power supply device comprising: a relay circuit that reduces the current to the field winding to such an extent that the power generation output is substantially stopped. 2. The power supply device according to claim 1, wherein the relay circuit is configured to cut off the current to the field winding by the detection output of the second stage.