JPH07274309A - Safety unit for charging vehicle mounted battery - Google Patents

Abstract

PURPOSE:To prevent short circuit of battery or electric shock when a vehicle is inadvertently driven while hauling an external battery charger during the charging operation of a vehicle mounted battery. CONSTITUTION:A battery 2 mounted on a vehicle is connected alternatively, through a switch 18, with a traveling circuit comprising a controller 3 and a traveling motor or a charging circuit connected with a battery charger 11. Since the switch 18 is used, two circuits are not closed simultaneously and since the charging circuit is interrupted during travel, short circuit and electric shock are prevented even it the vehicle is driven while hauling the battery charger 11. The switch 18 is controlled by a contactor coil 6' being conducted through a key switch 8. Hauling can be prevented when a limit switch is provided on the cover of a contactor 10 in place of the key switch 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle equipped with a battery (storage battery) for supplying electric power to a motor or the like, such as a battery forklift, and more particularly to an external power source with the battery mounted in the vehicle body. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for charging a battery mounted on a vehicle, which prevents a short circuit, an electric shock, or the like caused by the vehicle moving accidentally and dragging the battery charger when the battery is charged.

[0002]

2. Description of the Related Art Generally, an electric vehicle such as a battery forklift is equipped with a large-capacity and heavy battery for supplying electric power to a motor or the like. It is often done by connecting, and for that purpose, on the wall of the vehicle body,
It is usually fitted with a half of the connector that is connected to the battery by an internal charge cable, while the external part that extends from the battery charger (charger), which is an external power source for charging, is attached. The half of the connector provided at the end of the charge cable is fitted and electrically connected, and charging is performed by flowing a charging current with a slightly higher voltage from the battery charger.

FIG. 2 shows the entire configuration of an electric system of a conventional electric vehicle. A large and heavy battery 2 is mounted inside a vehicle body 1 shown by a chain line. In the case of the illustrated embodiment, a battery 2 having a relatively high voltage and a large capacity such as a terminal voltage of 80V is used. Reference numeral 3 is a controller for a vehicle driving motor (not shown), and inside the controller 3 (not shown) is basically an inverter for controlling the power output from the battery 2 in multiple levels of strength and weakness to supply it to the motor. In accordance with the driver's intention, in some cases, an electronic control device mainly including a microprocessor provided for automatically controlling the driving state of the motor via an inverter is accommodated.

Reference numeral 4 denotes a contactor contact. In this case, the contactor contact 4 is inserted in the middle of the high voltage power supply circuit 5. The high voltage power supply circuit 5 is the controller 3
At the same time as the power supply circuit of itself, it is also part of the power supply circuit to the motor (not shown) for driving the vehicle, and when the contactor contact 4 is opened (OFF), the power supply to the motor connected to the controller 3 is stopped. Then, the electric vehicle is configured so that it cannot move from the stopped place. Therefore, the contactor contact 4 needs to be closed (ON) in a normal driving state in which the electric vehicle travels.

The contactor contact 4 is a normally open contact that closes when the contactor coil 6 that drives it is electrically energized. In this example, the contactor coil 6 is inserted in the middle of the low-voltage power supply circuit 7. The low voltage power supply circuit 7
Is opened and closed by a key switch 8 operated by a driver. Since the energization of the contactor coil 6 does not require high voltage or large current, the low voltage power supply circuit 7
The battery 2 is drawn out from the middle of many unit storage battery groups connected in series inside the battery 2, for example, a position of a voltage of about 40V. The key switch 8 is operated by the driver, and maintains a closed (ON) state when the electric vehicle is in a driving state, and maintains an open (OFF) state when the electric vehicle is in a non-driving state.

Internal charge cables 9 (9a and 9b) are connected to both terminals of the battery 2, and they are connected to a vehicle-side connector half 10 attached to a location facing the outside, such as a side wall of the vehicle body 1. It is connected.

As an external power source for charging, for example, a battery charger 11 is fixedly installed in a charging station, and an external charge cable 12 (extending from the battery charger 11 and having a flexible and sufficient length) ( External connector half portions 13 that can be fitted and electrically connected to the connector half portion 10 on the vehicle body 1 side are attached to the tips of 12a and 12b).

When charging the battery 2, the vehicle is stopped at the charging station, the external charge cable 12 is extended, and the connector half 13 at the end is connected to the connector half 10 on the vehicle body 1 side for charging. Complete the circuit. Then, the charging operation of applying the charging voltage higher than the terminal voltage of the battery 2 from the battery charger 11 and flowing the charging current to the battery 2 through the charge cables 9 and 12 is performed. At this time, not only the vehicle is stopped but the key switch 8 is opened (OF
F), the contactor coil 6 is not energized by it, so the contactor contact 4 is also opened (OFF), and the controller 3 by the high-voltage power supply circuit 5
Also, the power supply to the motor (not shown) is cut off, and the vehicle cannot run.

However, depending on the configuration of the electric system of the conventional electric vehicle shown in FIG. 2, if the driver performs an operation to close (ON) the key switch 8 during charging due to misunderstanding or the like, the vehicle can run. If the driver mistakenly presses an accelerator pedal (not shown), the vehicle will start running even while charging, and the external charge cable 12 will cause the battery charger 11 to move while dragging. Become. As a result, the external charge cables 12a and 12b are cut off, and there is a possibility of short-circuiting at the cut parts. When the battery 2 is short-circuited, a very large current may flow, which may damage the battery 2 itself. If a person touches the cut portion, an electric shock may occur. , There is a high possibility of causing some external danger.

Further, according to the configuration of the conventional electric system, since the terminal of the battery 2 is always connected to the vehicle-side connector half portion 10, a person accidentally touches the electrode when the connector half portion 10 is opened. And, since the terminal voltage of the battery 2 always acts on it, there is a possibility of causing an electric shock accident. In addition, a conductor such as a metal piece is used for the connector half 10
The battery 2 may be short-circuited if it touches the electrode.

As described above, in the conventional example, there is a possibility that accidentally moving the electric vehicle during the charging operation of the battery 2 may cause the battery charger 11 to be dragged and cause an accident such as a short circuit or an electric shock. Since the terminal voltage of the battery 2 acts on the side connector half portion 10, the same problem may occur.

As other conventional techniques for solving this problem, Japanese Utility Model Laid-Open No. 1-105301 and Japanese Unexamined Patent Publication No. 51-1 have been proposed.
The one described in Japanese Patent No. 2517 has been proposed. These improved prior art features are generally in the configuration around the connector of the charge cable as shown in FIG. Since the schematic configuration of the electric system in the conventional electric vehicle shown in FIG. 3 has much in common with that of FIG. 2,
The same reference numerals are assigned to substantially the same components, and the overlapping detailed description will be omitted.

The difference between FIG. 3 and FIG. 2 is that the opening 14 formed in the side wall of the vehicle body 1 for the connector half 10 is closed except when charging and foreign matter enters. The open / close lid 15 for preventing the above-mentioned operation is provided with a limit switch 16 which is brought into contact with and closed (ON) at the closed position of the open / close lid 15. Further, the low voltage power supply circuit 7 is provided with a second switch in series with the key switch 8. Contactor contact 17 is inserted, and a contactor coil (not shown) is provided to operate the second contactor contact 17, and the second contactor coil is energized when the limit switch 16 is closed. Close contact 17 (ON)
It is configured as follows.

Therefore, in a normal operating state, the key switch 8 is ON, and when the charging operation is not performed, the opening / closing lid 15 is closed and the limit switch 16 is ON. As a result, the second contactor contact 17 is turned on, so that the low-voltage power supply circuit 7 is closed (ON). At that time, the contactor coil 6 is urged so that the first
The contactor contact 4 is also turned on and electric power is supplied to a motor (not shown) via the controller 3, so that the electric vehicle can travel freely.

When a battery 2 of an electric vehicle having an electric system as shown in FIG. 3 is connected to an external power source such as a battery charger 11 to receive a charging operation, a connector half outside the vehicle-side connector half 10 is used. The opening / closing lid 15 of the opening 14 is opened as shown in FIG. The limit switch 16
Turns off when it is separated from the opening / closing lid 15, the power supply to the contactor coil (not shown) is stopped, and the second contactor contact 17 also turns off. Therefore, even if the driver mistakenly turns on the key switch 8, the low-voltage power supply circuit 7 is closed (O
N) and the contactor coil 6 is not energized, so that the first contactor contact 4 does not turn on. As described above, the first contactor contact 4 is turned off during charging, thereby stopping the power supply from the controller 3 to the motor to prevent the vehicle from traveling, and the high charging voltage of the battery charger 11 causes the high voltage power supply circuit. It is possible to prevent a trouble from being applied to the controller 3 via the switch 5.

The improved conventional electrical system shown in FIG. 3 operates as described above, but in the unlikely event that the limit switch 16
Broke down and closed regardless of whether the open / close lid 15 was opened or closed (O
N), the second contactor contact 17 also remains ON, so that the configuration is similar to that of the conventional example shown in FIG. 2, and if the key switch 8 is accidentally turned ON during charging, the vehicle will When the vehicle is ready to run, there is a possibility that the dragging of the battery charger 11 may cause a short circuit or electric shock similar to the above-described conventional technique. The problem due to such a failure occurs not only by the limit switch 16 but also by a failure in which the contactor contact 17 is stuck in the ON state.

Further, also in the conventional example shown in FIG. 3, the relatively high terminal voltage of the battery 2 is constantly applied to the vehicle-side connector half portion 10. Therefore, when the opening / closing lid 15 is opened for charging work. If the electrode of the connector half portion 10 is accidentally touched with a hand, an electric shock may be caused, and if a metal piece or the like is touched, the terminals of the battery 2 may be short-circuited and the battery 2 may be damaged. Therefore, this point is not substantially improved compared with the conventional example of FIG. 2 except that the opening / closing lid 15 is closed.

[0018]

The present invention solves the above-mentioned problems in the conventional example as shown in FIG. 2 and the conventional example as shown in FIG. 3 proposed to improve the problem. At the same time, even if the battery charger accidentally drags while the battery is being charged, there is no risk of a battery short circuit or electric shock, and the system will always be on the safe side even if a switch malfunctions. To avoid danger, and to prevent accidents such as electric shock or short circuit in the connector half of the vehicle side,
An object of the present invention is to provide a safety device for charging a vehicle-mounted battery.

[0019]

As a means for solving the above problems, the present invention includes a battery mounted on a vehicle, a running circuit including a controller and a running motor, a connector and a charge cable, and an external circuit. And a charging circuit connected to the battery charger, a changeover switch for selectively completing one of the running circuit and the charging circuit by connecting the battery, and the changeover switch is operated. There is provided a safety device for charging a vehicle-mounted battery, comprising: a contactor coil for controlling the contactor coil; and a switch for controlling energization of the contactor coil.

[0020]

With the switch for controlling the energization of the contactor coil, the changeover switch is operated via the contactor coil to selectively complete only one of the running circuit and the charging circuit. The charging circuit is sometimes turned off, while the traveling circuit including the controller and the traveling motor is turned off when the charging work is performed.
It becomes FF. Also, since the battery is not connected to the connector of the charging circuit during traveling, even if the vehicle is accidentally operated and the battery charger is dragged, the battery will be short-circuited or an electric shock will occur. Is prevented.

[0021]

1 shows a schematic configuration of an electric system of an electric vehicle as an embodiment of the present invention. Constituent elements similar to those of the conventional technique shown in FIG. 2 described in detail above are denoted by the same reference numerals, and the duplicated description will be omitted. That is, 1 is a vehicle body of an electric vehicle, 2 is a battery,
3 is a controller, 5 is a high voltage power supply circuit, 7 is a low voltage power supply circuit, 8 is a key switch, 9 (9a and 9b) is a charge cable inside the vehicle, 10 is a half of the connector on the vehicle side, 11 is a battery charger, Reference numeral 12 (12a and 12b) denotes an external charge cable, and 13 denotes an external connector half.

As compared with the conventional example shown in FIG. 2 or 3, the feature of the embodiment of the present invention shown in FIG. 1 is that the first contactor contact 4 for opening and closing the high voltage power supply circuit 5 is not used, and the changeover switch is used. 18 is being used. The changeover switch 18 includes two fixed contacts 18a and 18b and a movable contact 18c that can be selectively contacted with the fixed contacts 18a and 18b. In this case, the fixed contact 18a is the controller 3
In addition, the fixed contact 18b is connected to the internal charge cable 9a,
The movable contact 18c is connected to one terminal (positive electrode) 2a of the battery 2 by the high-voltage power supply circuit 5, respectively.

Therefore, in the embodiment of FIG. 1 of the present invention, the internal charge cable 9a is not directly or constantly connected to one terminal 2a of the battery 2 as in the conventional example. Therefore, the terminal voltage of the battery 2 does not act on the vehicle-side connector half portion 10 except when the movable contact 18c of the changeover switch 18 is in contact with the fixed contact 18b, that is, except when the battery 2 is being charged.

By providing the changeover switch 18, the internal charge cable 9a and the high voltage power supply circuit 5 are provided.
It is absolutely impossible that the inlet 3a of the controller 3 forming a part of is connected. Contactor coil 6'for driving movable contact 18c of changeover switch 18
Like the contactor coil 6 in the conventional example, is provided in series with the key switch 8 in the low-voltage power supply circuit 7, but they are not necessarily the same because they are driven differently. The other terminal 2b of the battery 2 is connected as in the conventional example.

The embodiment of the present invention shown in FIG. 1 is configured in this way, and when the key switch 8 is closed (ON) by the driver, the movable contact 18c of the changeover switch 18 comes into contact with the fixed contact 18a. , The contactor coil 6 ′ drives the movable contact 18c so as to come into contact with the fixed contact 18b when the key switch 8 is opened (OFF). Therefore, the movable contact 18c always contacts with either the fixed contact 18a or 18b. However, the two contacts do not come into contact with each other at the same time, so that electrical connection between the fixed contacts 18a and 18b cannot occur.

Therefore, when the battery 2 is charged, the movable contact 18c of the changeover switch 18 comes into contact with the fixed contact 18b, and the battery 2 is connected to the charge cables 9a and 9b inside and the connector half 10 is connected.
And 13 and external charge cables 12a and 12b
Then, the charging circuit is completed by being connected to the battery charger 11. Further, when the vehicle is traveling, the driver turns on the key switch 8 so that the movable contact 18c of the changeover switch 18 is fixed.
By contacting a, the battery 2 can be connected to the controller 3 via the high voltage power supply circuit 5 to form a running circuit. Since the changeover switch 18 is provided in the embodiment of the present invention, the charging circuit and the traveling circuit are not closed at the same time.

Also, the key switch 8 is mistakenly charged during the charging operation.
Even if the accelerator pedal is stepped on and the vehicle is driven further, the movable contact 18c of the changeover switch 18 is switched to the fixed contact 18a side at that time, so the battery 2 Connector halves 10 and 13 and external charge cables 12a and 12b
There is no possibility of causing a short circuit or electric shock even if the battery charger 11 is dragged because it is not connected to.

As another embodiment of the present invention, instead of the key switch 8, a limit switch 16 operated by an opening / closing lid 15 as used in the conventional example shown in FIG.
Alternatively, the changeover switch 18 may be operated by the limit switch 16 and the contactor coil 6 ′.

In this case, the opening / closing lid 1 is used when the charging operation is performed.
When the switch 5 is opened, the limit switch 16 is turned on, and the movable contact 18c of the changeover switch 18 becomes the fixed contact 18b.
The charging circuit is formed by switching to the side. When the opening / closing lid 15 is closed after the charging work is completed, the limit switch 1
6 is turned off and the movable contact 1 of the changeover switch 18
8c is switched to the fixed contact 18a side to form a traveling circuit. Also in this case, as in the above-described embodiment,
Since the charging circuit and the traveling circuit cannot be formed at the same time, the traveling circuit will not be closed even if the traveling operation is mistakenly performed during the charging work, and the vehicle cannot travel. There is no risk of dragging the charger 11. Therefore, it goes without saying that there is no fear of short circuit of the battery or electric shock.

In each of the embodiments of the present invention, even if one of the parts fails, the running or charging selected by the change-over switch 18 cannot be performed, and the running circuit and the charging are still required. It can be said that the safety device for charging a vehicle-mounted battery according to the present invention has a fail-safe function, because the circuits do not close (ON) at the same time and there is no fear of causing any dangerous state.

[0031]

According to the present invention, the problems of the prior art are improved, and even if the battery charger is accidentally dragged while the battery is being charged, there is no danger of causing a short circuit of the battery or an electric shock accident. Depending on
It is also possible to prevent the battery charger from dragging itself. In addition, even if a switch or other component fails, the system will always operate on the safe side, providing a fail-safe function to avoid danger, thus ensuring the safety of electric vehicles equipped with a battery. It can be further enhanced.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an electric system in an embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of an electric system in a conventional example.

FIG. 3 is a diagram showing a schematic configuration of an electric system in another conventional example.

[Explanation of symbols]

 1 ... Vehicle main body 2 ... Battery 3 ... Controller 4 ... First contactor contact 5 ... High voltage power supply circuit 6, 6 '... Contactor coil 7 ... Low voltage power supply circuit 8 ... Key switch 9 ... Internal charge cable 10 ... Vehicle side Connector half 11 ... Battery charger 12 ... External charge cable 13 ... External connector half 15 ... Open / close lid 16 Limit switch 17 ... Second contactor contact 18 ... Changeover switch 18a, 18b ... Fixed contact 18c ... Moving contact

Claims (3)

[Claims] 1. A battery mounted on a vehicle, a traveling circuit including a controller and a traveling motor, a charging circuit including a connector and a charge cable connected to an external battery charger, the battery including the traveling circuit and the traveling circuit. A changeover switch that selectively completes any one of them by connecting to one of the charging circuits, a contactor coil that activates the changeover switch, and a switch that controls energization of the contactor coil are provided. A safety device for charging a battery mounted on a vehicle, which is characterized in that 2. The safety device for charging a battery mounted on a vehicle according to claim 1, wherein the switch for controlling energization of the contactor coil is a key switch operated by a driver. 3. The limit switch, which controls the energization of the contactor coil, is a limit switch which is attached to a vehicle body of the vehicle and is operated by an opening / closing lid that closes the connector half portion except when charging. 1. A safety device for charging a vehicle-mounted battery according to 1.