JP2581092Y2 - Battery reverse connection protection device for load drive device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery reverse connection protection device for a load driving device to which control power is supplied when a battery is connected to a power input terminal with a correct polarity.

[0002]

2. Description of the Related Art For example, in an agricultural machine, when not in use in winter or the like, a battery serving as a power source may be removed and stored, or one battery may be connected to another agricultural machine for use. Therefore, when the battery is connected to the machine at the time of use, there is a possibility that the battery may be reversely connected by mistake.

Therefore, conventionally, a protection circuit as shown in FIG. 2 is provided so that even if such a battery is reversely connected, the machine is not damaged or the battery is not discharged. Some have been done.

That is, in FIG. 2, a load driving device 1
It has a control circuit 2 inside and controls a large number of loads 3 by applying a control signal via a drive circuit 4. The power supply input terminal A of the control circuit 2 is connected to the battery connection terminal 1a via a reverse connection protection diode 5 of the illustrated polarity, and the other power supply input terminal B is connected to the battery connection terminal 1b.
It is connected to the.

The drive circuit 4 for driving the load 3 includes a transistor 4a and a diode 4b connected in parallel to the transistor 4a with the polarity shown in the drawing. The base of the transistor 4a is connected to the control output terminal of the control circuit 2.

In the protection relay 6, the relay coil 6
Both terminals of a are connected between the power input terminals A and B of the control circuit 2, and the relay switch 6b is connected between the emitter of the transistor 4a of each drive circuit 4 and the battery connection terminal 1b. One end of each load 3 is connected to the collector of the transistor 4a of the corresponding drive circuit 4, and the other end is connected to the battery connection terminal 1a.

The battery 7 is externally connected as a driving power source. The positive terminal 7a is connected to the battery connecting terminal 1a via the key switch 8, and the negative terminal 7b is connected to the battery connecting terminal 1b. Has become.

According to such a configuration, when the key switch 8 is turned on in a state where the battery 7 is connected with the correct polarity as shown in the figure, the battery 7 supplies power to the control circuit 2 and connects to the relay coil 6a. The energization turns on the relay switch 6b to form an energization path to the load 3. Thus, when a drive signal is output from the control circuit 2 to each drive circuit 4, the corresponding load 3 is controlled to be energized.

On the other hand, when the battery 7 is
a, 1b, the power supply to the control circuit 2 is cut off by the diode 5, and the relay coil 6a
, So that no current is supplied in the reverse direction.

[0010]

However, in such a conventional configuration, when the battery 7 is reversely connected, protection against reverse energization of the control circuit 2 and the load 3 is provided. for the user, when to turn on the key switch 8 with the intention of connecting the battery 7, so no action, the load driving device 1 is faulty or or battery 7 is not lie in the power consumption state There is a possibility that it takes time to recognize that the battery 7 is in the reverse connection state.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a battery for a load driving device capable of quickly recognizing a reverse connection of a battery with a simple configuration even if the battery is incorrectly connected. A reverse connection protection device is provided.

[0012]

SUMMARY OF THE INVENTION A battery reverse connection protection device of a load driving device according to the present invention is intended for a load driving device to which control power is supplied when a battery is connected to a power input terminal with a correct polarity. From the battery
A drive circuit for driving the load by the connected control output current path to the load, and notifying means, the from the battery
Connected to the power supply path to the notification means,
Notification driving means for supplying power to the means to perform a notification operation;
When the battery is reversely connected, the notification means is formed with an energization path not depending on the control output to the notification drive means to perform the notification operation, and when the battery is connected with the correct polarity, The current path and the front of the load
And a switching means for switching and connecting to the power supply path of the notification means .

[0013]

According to the battery reverse connection protection device of the load driving device of the present invention, when the battery is correctly connected to the power input terminal, control power is supplied to the load driving device, and at this time, switching is performed. The means is a load energizing path.
And by switching to the energizing path of the notifying means, it is possible to perform the power cutoff control by the control output to the drive circuit for the load, and to the notifying means to the notifying drive means.
The notification operation can be performed by giving the control output . On the other hand, when the battery is reversely connected, the control power is not supplied, and the switching means
Since the power supply path to the load and the power supply path to the notification drive unit are not formed, the notification unit performs the notification operation by forming the power supply path that does not depend on the control output, so that the elements constituting the drive circuit are protected. And the user can quickly recognize that the battery has been reversed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

That is, in FIG. 1, a load driving device 11 incorporated in an agricultural machine or the like has a control circuit 12 therein, and supplies a control signal to a large number of loads 13 via a driving circuit 14 to control driving. Is what you do. The power supply input terminal A of the control circuit 12 is connected to the battery connection terminal 11a via a reverse connection protection diode 15 of the illustrated polarity, and the other power supply input terminal B is connected to the battery connection terminal 11b.

The driving circuit 14 for driving the load 13 includes a transistor 14a and a diode 14b connected in parallel to the transistor 14a with the polarity shown in the drawing. The base of the transistor 14a is connected to the control output terminal of the control circuit 12, respectively.

The protection relay 16 has a function as a switching means. Both terminals of the relay coil 16a are connected between the power input terminals A and B of the control circuit 12, and the normally open contact a of the relay switch 16b. Is connected to the emitter of the transistor 14a of each drive circuit 14, and the movable contact c is connected to the battery connection terminal 11b. The normally closed contact b of the relay switch 16b is connected to the battery connection terminal 11a via a notification circuit 18 serving as notification means formed by connecting a buzzer 17a and an indicator lamp 17b in parallel.

One end of each load 13 is connected to the collector of the transistor 14a of the corresponding drive circuit 14, and the other end is connected to the battery connection terminal 11a.

A notification driving means for driving the notification circuit 18
All of the driving circuits 19 include a transistor 19a and a diode 19b connected in parallel to the transistor 19a with the polarity shown in the drawing. The base of the transistor 19a is connected to a control output terminal of the control circuit 12, and the collector is a relay switch 1
The emitter is connected to the normally open contact a of the relay switch 16b.

The battery 20 is externally connected as a driving power source, and its positive terminal 20a is connected to the key switch 2
1, the negative electrode terminal 20b is connected to the battery connection terminal 11b.

According to such a configuration, when the key switch 21 is turned on in a state where the battery 20 is connected with the correct polarity as shown in the figure, the battery 20
2 and energize the relay coil 16a to establish a conductive state between the movable contact c of the relay switch 16b and the normally open contact a, thereby forming an energizing path to the load 13. Thus, when a drive signal is output from the control circuit 12 to each drive circuit 14, the corresponding load 13 is controlled to be energized.

On the other hand, when the battery 20 is
1a and 11b, the diode 15
As a result, the power supply to the control circuit 12 is cut off, whereby the power is not supplied to the relay coil 16a, and the reverse power supply is prevented.

In this state, a current path from the positive terminal 20a of the battery 20 to the negative terminal 20b of the battery 20 via the key switch 21, the notification circuit 18, the normally closed contact b and the movable contact c of the relay switch 16b is established. The buzzer 17a of the notification circuit 18 and the display lamp 1 are formed.
When the power is supplied to 7b, it is notified that the battery is in the reverse connection state.

When the battery 20 is normally connected, the control circuit 12 outputs a control signal to the drive circuit 14 so that the notification circuit 18 can be driven. Even in the state, the buzzer 17a and the display lamp 17b are used for other notification operations.
And can be operated.

According to the present embodiment, the notification circuit 18 is connected between the normally closed contact b of the relay switch 16b and the battery connection terminal 11a. In the case of reverse connection, these can be made to perform a notification operation, and the user can be quickly notified of the notification operation.

Further, according to the present embodiment, the notification circuit 18 is controlled by the control circuit 12 while the battery 20 is normally connected.
Therefore, other notification operations can be performed even when the load 13 is in a normal drive control state.

In the above embodiment, a configuration is used in which a parallel circuit of the buzzer 17 and the display lamp 18 is used as the notification means. However, the present invention is not limited to this, and a configuration in which only one of them is used may be used.

[0028]

According to the battery reverse connection protection device, according to the invention present invention in the load driving device, when the battery is reversely connected to the power supply input terminal, the switching means, Oyo current path to the load
Current path to the fine informing driving means a state that does not form, and
In addition, for the notification means, a notification operation can be performed by forming an energization path that does not depend on the control output, so that the user can be quickly notified of the reverse connection state of the battery and the battery can be correctly When connected, the notification means can be caused to perform the notification operation by the control output to the notification drive means, so that another notification operation by the control output can be performed without providing a separate notification means. It works.

[Brief description of the drawings]

FIG. 1 is an electrical configuration diagram showing an embodiment of the present invention.

FIG. 2 is a diagram corresponding to FIG. 1 showing a conventional example.

[Explanation of symbols]

11 is a load driving device, 12 is a control circuit, 13 is a load,
4 is a drive circuit, 15 is a diode, 16 is a protection relay (switching means), 17a is a buzzer, 17b is a display lamp,
18 is a notification circuit (notification means), 19 is a drive circuit (notification drive)
Motion means), 20 denotes a battery, 21 is a key switch.

Claims (1)

(57) [Scope of request for utility model registration] 1. A load driving device to which control power is supplied when a battery is connected to a power input terminal with a correct polarity, wherein the driving device is connected to an energizing path from the battery to the load and drives the load by a control output. A circuit, a notifying means, and a power supply path from the battery to the notifying means.
Power is supplied to the notification means by a control output to perform a notification operation.
And a notification drive unit for performing the notification operation by forming an energization path that does not depend on a control output to the notification drive unit when the battery is reversely connected, so that the battery has a correct polarity. When connected with the load energizing path and before
And a switching means for switching and connecting to an energizing path of the notification means .