JPH03213662A - Power supply device for vehicle - Google Patents

Abstract

PURPOSE:To prevent a battery from being exhausted of electricity by providing a device with a change-over relay switch making change-over between series joint and parallel joint in a plurality of batteries, and concurrently providing the device with a charging device charging a plurality of the batteries at the time of parallel joint bad with a display means indicating warning display at the time of series joint. CONSTITUTION:When a key switch 16 is changed over to a starter terminal 15 at the time of starting an engine, the exciting coil 11 of a series change-over switch 4 is energized so that 2 batteries 2 and 3 are jointed in series. In this case, the exciting coil 24 of a warning relay switch 23 is also energized so that a lamp 22 is lit. A magnet switch 20 is then turned on with the exciting coil 18 of a feeding relay switch 17 excited, and a starter 6 is then energized so that the engine is thereby started. When the key switch 16 is later turned back onto an 'ON' terminal 14, electricity to the respective exciting coils 18 and 11 is interrupted, and the batteries 2 and 3 are joined in parallel so that they are ready for being charged by a charging device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power supply device for a vehicle that connects a plurality of batteries in series or in parallel and generates different voltages depending on the state of use.

[Prior Art] As a technique of this kind, a technique disclosed in Japanese Utility Model Application Laid-Open No. 59-159143 is known. This technology connects two batteries in series to operate the high-voltage starter, and after starting the starter, connects the two batteries in parallel to reduce the voltage and provide power to each load on the vehicle. There is something that supplies it.

[Problem to be solved by the invention] Switching between series connection and parallel connection of two batteries is done in one step.
We will explain the problems that may occur when using two mechanical series/parallel switching relay switches.

If two batteries are held in series, such as when the movable contact of a series/parallel relay switch is welded to the side of the contact that makes the series connection, one or both batteries will no longer be charged. That is, if two batteries are held in series, one or both batteries will die.

This difference is caused by the difference in the connection of the charging device to the two batteries, for example,
As shown in Publication No. 43, when a battery is connected in series and a charging device is connected to both poles of the battery on the negative side, if the battery is kept in series, the battery on the positive side will not be charged. For this reason, the battery on the positive side will eventually die, and if a battery is connected in series and a charging device is connected to both poles, if it is held in series,
A high voltage will be applied to the charging device, so both batteries will not be charged and both batteries will eventually die.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle power supply device that can prevent the battery from dying when the devices are connected in series.

[Means for Solving the Problems] In order to achieve the above object, the vehicle power supply device of the present invention employs the following technical means.

A vehicle power supply device includes a plurality of batteries from which output voltages can be taken out independently, a mechanical series/parallel switching relay switch that switches the plurality of batteries between series connection or parallel connection, and the plurality of batteries connected to each other. The battery includes a charging device that charges the plurality of batteries when they are connected in parallel, and a display means that displays a warning to a vehicle occupant when the plurality of batteries are connected in series.

[Function] In the vehicle power supply device configured as described above, if multiple batteries are held in series due to a malfunction of the series/parallel switching relay switch, etc., the display means will display a message to the vehicle occupant indicating that the batteries are connected in series. 1 is displayed to the vehicle occupants.

Therefore, the vehicle occupant can know from the display means that a plurality of batteries are held in series, or in other words, that the state of charge of the batteries is not appropriate.

[Effects of the Invention] As explained above, when a plurality of batteries are held in series, the vehicle occupant can see through the display means that the batteries are connected in series. Therefore, even if a plurality of batteries are held in series, it is possible to prevent the vehicle occupant from running out of battery power.

[Example] Next, a vehicle power supply device of the present invention will be described based on an example shown in the drawings.

(Configuration of Embodiment) FIGS. 1 and 2 show a first embodiment, and FIG. 1 shows an electric circuit of a vehicle power supply device.

The vehicle power supply device 1 shown in this embodiment has two cases each housed in independent cases or two cases housed in one case so that the output voltage can be taken out independently.
It is equipped with two batteries 2.3. These two batteries 2.
No. 3 has a rated output voltage of 12 V, and can be switched between series connection and parallel connection by one mechanical series/parallel switching relay switch 4.

Note that the two batteries 2.3 shown in this embodiment are normally connected in parallel to supply a voltage of 12V to the electrical equipment 5, and are switched to series connection only when the starter 6 is activated, resulting in a voltage of 24V.
The starter 6 is operated by the high voltage of V, and the engine (
(not shown) has improved startability. After the engine is started, the two batteries 2.3 are connected in parallel again to supply a voltage of 12V to the electrical equipment 5. Note that even when the two batteries 2.3 are connected in series by the series/parallel switching relay switch 4, the electric device 5 is connected to only one battery 3 and a voltage of 12V is applied to it.

Next, the series/parallel switching relay switch 4 will be specifically explained.

The series/parallel changeover relay switch 4 connects two batteries 2.3
two pairs of parallel fixed contacts 7.8 for connecting in parallel;
It is provided with a pair of series fixed contacts 9 for connecting the two batteries 2.3 in series, and can be switched between series connection and parallel connection depending on the movement state of the movable contact 10. The movable contact 10 is moved by an exciting coil 11 and a return spring (not shown). When the excitation coil 11 is de-energized, the return spring moves the movable contact 10 and closes the two pairs of parallel fixed contacts 7.8. In addition, when the excitation coil 11 is energized,
The movable contact 10 moves by the magnetic force generated by the excitation coil 11, overcoming the biasing force of the return spring, and the series fixed contact 9 is closed. Note that the excitation coil 11 is
The control circuit 12 controls the energization.

The control circuit 12 controls the energization of the excitation coil 11 of the series/parallel switching relay switch 4 according to the setting state of a key switch 16 that has an off terminal 13, an on terminal 14, and a starter terminal 15, and also controls the energization of the excitation coil 11 of the series/parallel switching relay switch 4. It also controls the energization of the 17 excitation coils 18.

The electrostatic relay switch 17 consists of an excitation coil 18 and a normally open contact 19. When the excitation coil 18 of the electrostatic relay switch 17 is energized, the normally open contact 19 closes and the magnet switch 20 of the starter 6 is turned on. do.

Note that when the magnetic switch 20 is turned on, the output voltage of the two batteries 2.3 connected in series is applied to the starter 6.
is applied to

Next, the series/parallel switching relay switch 4 by the control circuit 12
An example of energization control of the energizing relay switch 17 will be explained using the flowchart of FIG. 2.

First, in step S1, it is determined whether the key switch 16 is set to the starter terminal 15. If the result of this determination is No, the process returns to step S1, and if YES, the excitation coil 11 of the series/parallel switching relay switch 4 is energized in step S2. Next, step S
In step S3, it is determined whether a predetermined period of time has elapsed.If the result of this determination is NO, the process returns to step S3 and YES is determined.
In this case, in step S4, the energizing relay switch 1
The excitation coil 18 of No. 7 is energized.

Next, in step S5, it is determined whether the key switch 16 is set to the starter terminal 15.

If the result of this judgment is YES, the process returns to step S5 and N
In the case of O, the energization of the excitation coil 18 of the energizing relay switch 17 is stopped in step S6. Next, in step S7, it is determined whether a predetermined time has elapsed. If this judgment result is NO, return to step S7,
If YES, in step S8, the excitation coil 11 of the series/parallel switching relay switch 4 is de-energized, and then the process returns.

The above-mentioned predetermined time is provided to allow the magnet switch 20 to generate sparks that are generated when the contact type switch is turned on and off. For this reason, the predetermined time is set short. Further, although the above control is performed by a microcomputer, it may also be performed using a timer such as a capacitor.

The vehicle power supply system f1 includes two batteries 2 connected in parallel.
．． A charging device 21 is provided for charging the battery.

In the charging device 21 of this embodiment, when two batteries 2.3 are connected in series, the charging device 21 is connected to both poles of the series-connected batteries.

The vehicle power supply device 1 includes a display means that informs the vehicle occupant that the r battery is connected in series when the two batteries 2.3 are connected in series.

The display means of this embodiment is a lamp 22 provided within the visual range of the vehicle occupant, and is energized and controlled by a warning relay switch 23. The warning relay switch 23 includes an excitation coil 24 that is energized only when the two batteries 2.3 are connected in series, and a normally open switch 25 that is turned on when the excitation coil 24 is energized. For this reason, 2
When two batteries 2.3 are connected in series, the lamp 22
lights up to indicate to the vehicle occupants that the two batteries 2.3 are connected in series.

(Operation of the embodiment) Next, the operation of the above embodiment will be briefly explained.

In order to start the engine, the vehicle occupant presses the key switch 16.
When the key switch 16 is manually operated and the key switch 16 is switched to the starter terminal 15, the excitation coil 11 of the series/parallel switching relay switch 4 is first energized, and the two batteries 2.3 are connected in series. Thereafter, the excitation coil 18 of the energizing relay switch 17 is energized, and the magnet switch 20 is turned on. Then, a voltage of 24V is applied to the starter 6, the starter 6 is driven, and the engine is started.

After starting the engine, when the key switch 16 is returned to the ON terminal 14, the excitation coil 18 of the coupling relay switch 17 is de-energized and the magnet switch 20 is turned off. Therefore, the starter 6 stops driving.

After that, the excitation coil 11 of the series/parallel switching relay switch 4
is de-energized and the two batteries 2.3 are connected in parallel.

On the other hand, when the two batteries 2.3 are connected in series by switching the series/parallel switching relay switch 4, the excitation coil 24 of the warning relay switch 23 is energized and the lamp 22 is turned on. By lighting the lamp 22, the vehicle occupant can know that the two batteries 2.3 are connected in series.

If a problem occurs in which the two batteries 2.3 are held in series, such as when the movable terminal of the series/parallel switching relay switch 4 is welded to the series fixed contact 9, the key switch 16 is turned off to the off terminal 13 or turned on. Even when the terminal 14 is set, the lamp 22 lights up. For this reason, the vehicle occupant is aware that the lighting of the lamp 22 indicates that the two batteries 2.3 are maintained in series, or in other words, that the connection between the two batteries 2.3 and the charging device 21 is not appropriate. can be known.

(Effects of Example) The vehicle power supply device 1 of this example has two batteries 2.3.
When the R batteries are maintained in series, the lamp 22 turns on, indicating that the r batteries are connected in series. Therefore, when a problem occurs in which the two batteries 2.3 are held in series, it becomes possible for the vehicle occupant to prevent the battery from dying.

Specifically, even if the two batteries 2.3 are held in series, the batteries will not die immediately, so if the lamp 22 lights up, take measures such as requesting repair as soon as possible.

The display means of this embodiment employs a very simple and simple structure consisting of a lamp 22 and a warning relay switch 23. Therefore, it is possible to suppress the increase in cost due to the provision of the display means, and also to suppress the failure probability of the display means itself.

(Modified example) In this embodiment, the detection means (warning relay switch 23) was provided at the part where voltage is applied only when connected in series to detect the state of series connection, but the voltage generated when connected in series It is also possible to detect the state of series connection. Specifically, a voltage detection means is provided at the part to which a high voltage is applied when connected in series, and a display means is displayed according to the detected value of the voltage detection means. Measures such as setting a lamp (display means) that lights up only when a voltage higher than a specified voltage (for example, 17V or higher) is applied to the part where high voltage is applied when connected in series. Also good.

Of course, instead of the contact type warning relay switch 23, other elements such as a transistor may be used to provide a non-contact type.

It may be provided that the display means is activated after a predetermined time (for example, 1 minute) has elapsed since the batteries 2.3 are connected in series, that is, the display is activated only when the series connection is maintained due to a malfunction. Although we have shown an example in which a lamp 22 is provided only to indicate that the batteries 2.3 are connected in series, it is also possible to use existing display means such as a charge lamp in combination. good.

Although the lamp 22 is shown as an example of the display means, other low-voltage light emitting means such as a light emitting diode, visual display means using a liquid crystal panel, etc., and auditory display means using sounds, chimes, buzzers, etc. may also be used. .

When the two batteries 2.3 are connected in series, the charging device is connected to both poles of the series-connected batteries. The charging device may be connected to the battery.

An example has been shown in which the batteries 2.3 are connected in series when operating the starter 6, but for example, when connecting a high voltage external device, the batteries may be connected in series manually or by an instruction signal from the external device. In a vehicle equipped with a high-voltage electric device (for example, a light with a large amount of light), batteries may be connected in series when the high-voltage electric device is used.

Although an example in which two batteries 2.3 are used as an example of a plurality of batteries is shown, three or more batteries may be used.

(Second Embodiment) FIGS. 3 to 5 show a second embodiment, and FIGS. 3 and 4 show cross-sectional views of a series-parallel switching relay switch.

This embodiment relates to the structure of a series/parallel switching relay switch 4.

The series/parallel switching relay switch 4 of this embodiment includes a movable contact 10 movably provided within an insulating container, an armature 26 fixed to the movable contact 10, an excitation coil 11 that applies an attractive force to the armature 26, and a movable contact 10. 2 pairs of parallel fixed contacts 7.8 that the movable contact 10 comes into contact with when the excitation coil 11 is de-energized and the movable contact 10 is returned by the return spring 27. , the armature 26 is the excitation coil 1
A pair of series fixed contacts 9 are provided with which the movable contact 10 comes into contact when the movable contact 10 is attracted to the contact point 9.

The movable contact 10 has a three-layer structure in which conductive contacts made of silver or copper are fixed to both sides of an insulating material 28, and the contact 29.30 on the side that comes into contact with the parallel fixed contact 7.8 has two
The pair of parallel fixed contacts 7 and 8 are divided into two parts so as to be connected independently. Further, the contact 31 on the side that comes into contact with the series fixed contact 9 is integrally provided to connect the pair of series fixed contacts 9.

The surface of the contact 31 that comes into contact with the series fixed contact 9 is formed with a large number of concavities and convexities that become narrower toward the tip. That is, the contact surface with the series fixed contact 9 is provided in the shape of a sawtooth with a jagged cross section.

The operation of the second embodiment will be briefly explained.

For example, when the excitation coil 11 is de-energized, the movable contact 10
When the movable contact 10 returns due to the action of the return spring 27, the movable contact 10 gets caught in the insulating container and tilts (see Fig. 5), and the two batteries 2.3 are connected in series and in parallel. , may occur simultaneously.

In this way, if the series connection state and the parallel connection state of the two batteries 2.3 occur simultaneously, the two batteries 2.3 will be connected in parallel.
3, the positive and negative poles are short-circuited. At this time, fixed contact 7.8 for parallel, fixed contact 9 for series
A large current flows through each contact 29, 30, 31 due to the short circuit. Then, the tip 31a of the uneven surface of the contact 31 that was in contact with the series fixed contact 9 is melted by the large current.

Therefore, the short circuit between the two batteries 2.3 is cut off, and problems such as damage to the series/parallel switching relay switch 4, wiring, etc. due to temperature rise are prevented.

Conventionally, when the two batteries 2.3 are short-circuited due to a malfunction in the series/parallel switching relay switch 4, as a means to prevent damage to the series/parallel switching relay switch 4, wiring, etc., each of the two batteries 2.3 is , fuses were installed in parallel. However, when fuses are connected in parallel to each of the two batteries 2.3, the two batteries 2.3 are When the two batteries 2.3 are connected and charged, there is a high possibility that there will be a difference in the charging currents applied to the two batteries 2.3.

When there is a difference in the charging current applied to the two batteries 2.3,
Since the two batteries 2.3 have different amounts of charge, there is a difference in the lifespan of the two batteries 2.3.

However, in this embodiment, without providing a fuse,
Since the short circuit of the two batteries 2.3 is interrupted, the 2
The life difference between the two batteries 2.3 can be reduced.

On the other hand, since the tip 31a of the uneven surface of the contact 31 is provided thinly, the contact pressure between the contact 31 and the series fixed contact 9 is stabilized under normal conditions. Therefore, the difference in contact resistance between the series/parallel switching relay switches 4 becomes small.

In this embodiment, the tip 31 is formed on the surface of the contact 31.
Although a thin unevenness is provided, unevenness with a thin tip may be provided on the surface of the series fixed contact 9 with which the contact 31 comes into contact.

[Brief explanation of drawings]

1 and 2 show a first embodiment, in which FIG. 1 is an electric circuit of a vehicle power supply device, and FIG. 2 is a flowchart showing an example of the operation of a control circuit. Figures 3 to 5 show the second embodiment, in which Figure 3 is a front sectional view of the series-parallel switching relay switch, Figure 4 is a side sectional view of the series-parallel switching relay switch, and Figure 5 is the movable series-parallel switching relay switch. FIG. 2 is a sectional view of a main part of the series/parallel switching relay switch showing a state in which the contacts are caught in an insulating container in which the contacts are housed. In the figure 1...Vehicle power supply device 2.3...Battery 4...Series/parallel switching relay switch 21...Charging device 22...Lamp (display means) Agent Kenji Ishiguro 82 Figure 451! Figure 3 5rIli

Claims (1)

[Claims] 1) (a) A plurality of batteries from which output voltages can be taken out independently, and (b) one mechanical series-parallel switch that switches the plurality of batteries between series connection or parallel connection. (c) when the plurality of batteries are connected in parallel,
A vehicle power supply device comprising: a charging device that charges the plurality of batteries; and (d) a display unit that displays a warning to a vehicle occupant when the plurality of batteries are connected in series.