JP2007014165A - Reverse connection protection device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reverse connection protection device for a vehicle that can achieve power saving, low heat generation and a low-voltage drop by surely protecting electric loads at the reverse connection of a battery by using a latched relay. <P>SOLUTION: The latched switching electromagnetic relay 3 is arranged between the battery 2 and the electric loads 14, 15, and a diode 11 is connected to an electromagnetic relay drive means 5 in parallel therewith that drives an exciting coil by making a current flow to the coil, so that a direction is set forward where the current flows to the battery 2 via the exciting coil that drives the connecting point of the latched switching electromagnetic relay 3 to a releasing side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a reverse connection protection device for a vehicle that protects an electric load when a battery that supplies electric power to various electric loads mounted on the vehicle is connected in reverse polarity (reverse connection).

  In a vehicle such as an automobile, a battery (storage battery) is used as a power source for supplying power to various electric loads. However, when the battery is replaced, the battery may be connected in reverse polarity (reverse connection) by mistake. There is sex. Therefore, in a vehicle, it is necessary to protect an electrical load when the battery is reversely connected, and as a countermeasure therefor, a technique for providing a fuse that cuts off power supply to the electric load when the battery is reversely connected has been proposed (for example, (See Patent Document 1).

  Specifically, Patent Document 1 includes a circuit that short-circuits a safety device (circuit breaker) including a battery and a fuse, and a switch that opens and closes the circuit. Based on the detection information of the reverse connection current, A reverse connection protection device for controlling a switch is disclosed.

  However, since it is necessary to replace the fuse once it is used as a circuit breaker, the conventional technique has a problem that it is necessary to prepare a spare fuse. Further, in such a conventional technique, it is necessary to provide means for detecting a reverse connection current, a switch, and a means for controlling the switch only for the purpose of protecting the reverse connection, resulting in a system price increase. There was also.

  On the other hand, as a technique for protecting the reverse connection of an electric load without using a fuse, a technique for providing an electromagnetic relay between the battery and the electric load has been proposed (for example, Patent Document 2 and Patent Document 3). reference.).

  Specifically, in Patent Document 2, an electromagnetic relay is provided between a battery and an electric load, and when the battery is normally connected, the electromagnetic relay is always energized as the ignition key is turned on. A technique is disclosed in which an electromagnetic relay is maintained in an off state by closing a battery and preventing a current in the reverse direction from flowing by a diode provided in a relay excitation circuit when the battery is reversely connected.

In Patent Document 3, an electromagnetic relay is provided between a battery and an electric load, and a diode is provided in parallel with a switching element that drives the electromagnetic switch, and current is passed by the diode when the battery is reversely connected. A technique for forcibly turning off each contact of an electromagnetic switch is disclosed.
Japanese translation of PCT publication No. 2004-527997 JP-A-5-30653 JP 2002-238135 A

  By the way, in a vehicle, it is desirable to suppress power consumption as much as possible with an increase in the type and number of electric loads to be mounted. From this point of view, when using a relay that switches between opening and closing of a circuit to protect the reverse connection of an electrical load, the relay is temporarily energized only at the time of switching, and power is maintained while the open or closed state is maintained. It is desirable to use a latch-type relay that has excellent features such as power saving, low heat generation, and low voltage drop.

  However, in the conventional techniques described in Patent Document 2 and Patent Document 3 described above, when the electromagnetic relay is replaced with a latch-type relay, the excitation coil current does not flow when the battery is reversely connected. There was a problem that could not be done.

  The present invention was devised in view of the above-described conventional situation, and it is possible to reliably protect an electrical load when a battery is reversely connected using a latch-type relay, thereby reducing power consumption and reducing power consumption. An object of the present invention is to provide a reverse connection protection device for a vehicle which can realize heat generation and low voltage drop.

  In order to achieve the above object, the reverse connection protection device for a vehicle according to the present invention is provided with a latch-type relay between a battery and an electric load, and an excitation coil for driving the contact of the latch-type relay to the open side A driving means for driving the battery by supplying a current is provided, and a diode is connected in parallel to the driving means so that the direction in which the current flows to the battery via the exciting coil is the forward direction. Thereby, in the reverse connection protection device for a vehicle according to the present invention, when the battery is reversely connected, current flows from the diode to the battery via the exciting coil, and the contact of the latch type relay is driven to the open side.

  According to the reverse connection protection device of the present invention, when the battery is reversely connected, the contact of the latch-type relay is driven to the open side, and the battery and the electrical load are electrically disconnected, so that power saving, low heat generation, and low While realizing the voltage drop, it is possible to reliably protect the electric load when the battery is reversely connected.

  Hereinafter, specific embodiments of a vehicle reverse connection protection device to which the present invention is applied will be described in detail with reference to the drawings.

  This reverse connection protection device for a vehicle is for protecting an electric load when a battery as a power source for supplying electric power to various electric loads mounted on the vehicle is reversely connected in reverse polarity (reverse connection). It is. In particular, this reverse connection protection device for a vehicle is provided with a latch-type relay between a battery and an electric load that is temporarily energized only at the time of switching and does not require electric power while maintaining an open state or a closed state. It is.

(First embodiment)
First, a reverse connection protection device for a vehicle according to a first embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, the reverse connection protection device for a vehicle is applied to a power supply circuit for a vehicle that supplies electric power to an electric load 14, 15 from a generator (alternator) 1 and a battery 2 as a storage battery, The electric loads 14 and 15 are protected when the battery 2 is reversely connected.

  Specifically, the reverse connection protection device for a vehicle according to the present embodiment is configured by providing a latch opening / closing electromagnetic relay 3 which is a kind of latch type relay between the battery 2 and the electric loads 14 and 15.

  The latch opening / closing type electromagnetic relay 3 allows a current to flow only when opening and closing, so that power consumption is extremely low and contact pressure can be increased, so that a low contact resistance can be achieved. Ideal for relays that open and close large current power circuits.

  Such a latch opening / closing type electromagnetic relay 3 generally has two terminals, that is, a SET terminal and a RESET terminal. By passing a current through the SET terminal, an excitation coil connected to the SET terminal is excited. While the contact is driven to the closed side, by passing a current through the RESET terminal, the excitation coil connected to the RESET terminal is excited and the contact is driven to the open side. In order to realize such driving, electromagnetic relay driving means 4 and 5 that are driven by flowing current through the exciting coil are electrically connected to the SET terminal and the RESET terminal of the latch opening / closing electromagnetic relay 3, respectively. Yes.

  The electromagnetic relay driving means 4 and 5 are each configured using a transistor or the like. When the electromagnetic relay driving means 4 and 5 are configured using transistors, each emitter terminal is connected to the ground, and each collector terminal is connected to each of the SET terminal and the RESET terminal of the latch opening / closing electromagnetic relay 3. The Therefore, in the latch opening / closing type electromagnetic relay 3, when the electromagnetic relay driving means 4 is turned on, a current flows through the SET terminal, and accordingly, the contact is driven to the closed side, while the electromagnetic relay driving means 5 is turned on. By setting the ON state, a current flows through the RESET terminal, and accordingly, the contact is configured to be driven to the open side.

  The electromagnetic relay driving means 4 and 5 are controlled by a microprocessor 7 that is driven by electric power supplied from the constant voltage power circuit 6. Specifically, when the electromagnetic relay driving means 4 and 5 are configured using transistors, the microprocessor 7 is connected to each base terminal. Here, the constant voltage power circuit 6 is electrically connected to the upstream side of the latch opening / closing electromagnetic relay 3 in a state where reverse connection protection is applied. Therefore, in the reverse connection protection device for a vehicle according to the present embodiment, electric power is supplied from the constant voltage power supply circuit 6 to the microprocessor 7 without being affected by the opening / closing operation of the latch opening / closing electromagnetic relay 3, and the electromagnetic relay driving The means 4 and 5 can be controlled.

  Note that the microprocessor 7 may also serve as drive control for the power supply control means 8 and 9 for controlling power supply to the electric loads 14 and 15, for example. Specifically, when the power supply control means 8 for controlling the electric load 14 is configured using a semiconductor relay made of an n-channel MOS-FET (Metal Oxide Semiconductor-Field Effect Transistor) or the like, The machine 1 and the latch open / close electromagnetic relay 3 are connected, the electric load 14 is connected to the source terminal, and the microprocessor 7 is connected to the gate terminal. Drive control can be performed. When the power control means 9 for controlling the electric load 15 is configured by using an electromagnetic relay, the power control is performed by controlling the transistor 10 and the like driven by flowing a current through the exciting coil by the microprocessor 7. The drive control of the means 9 can be performed. As described above, in the reverse connection protection device for a vehicle according to the present embodiment, the microprocessor 7 also serves as the drive control of the power supply control means 8 and 9, so that an inexpensive system can be constructed.

  In the reverse connection protection device for a vehicle having such a configuration, when the battery 2 is normally connected, a current flows through the exciting coil connected to the SET terminal of the latch opening / closing electromagnetic relay 3, and the contact is closed. Thus, the generator 1 and the electrical loads 14 and 15 that are electrically connected to the downstream side of the latch opening / closing electromagnetic relay 3 are electrically connected to the battery 2.

  On the other hand, when the battery 2 is reversely connected, it is necessary to drive the latch opening / closing electromagnetic relay 3 to the open side to electrically disconnect the battery 2 from the generator and the electric loads 14 and 15 to protect them. For this reason, in the reverse connection protection device for a vehicle according to the present embodiment, when the battery 2 is reversely connected, in order to pass a current through the exciting coil connected to the RESET terminal of the latch open / close electromagnetic relay 3, A diode 11 is provided in parallel with the electromagnetic relay driving means 5 connected to the RESET terminal. Specifically, the diode 11 has an anode terminal connected to the ground and a cathode terminal connected to the electromagnetic relay driving means 5. That is, the diode 11 is in parallel with the electromagnetic relay driving means 5 so that the direction in which current flows to the battery 2 through the exciting coil connected to the RESET terminal of the latch opening / closing electromagnetic relay 3 is the forward direction. Connected.

  Thereby, in the reverse connection protection device for a vehicle according to the present embodiment, when the battery 2 is reversely connected, it is composed of the ground, the diode 11, the exciting coil connected to the RESET terminal of the latch opening / closing electromagnetic relay 3, the fuse and the fusible link. Thus, a current path to the overcurrent breaker 12, the battery 2, and the ground is formed. That is, in the reverse connection protection device for a vehicle according to the present embodiment, when the battery 2 is reversely connected, a current flows through the exciting coil connected to the RESET terminal of the latch opening / closing electromagnetic relay 3, so that the contact is driven to the open side. become.

  Therefore, in the reverse connection protection device for a vehicle of this embodiment, when the battery 2 is reversely connected, the generator 1 and the electric loads 14 and 15 that are electrically connected to the downstream side of the latch opening / closing electromagnetic relay 3 are connected to the battery 2. It will be electrically disconnected and protected against reverse connection. In the reverse connection protection device for a vehicle according to the present embodiment, when the reverse connection of the battery 2 is eliminated, a current flows through the excitation coil connected to the SET terminal of the latch opening / closing type electromagnetic relay 3 and is automatically The contact is driven to the closed side, and the generator 1 and the electrical loads 14 and 15 electrically connected to the downstream side of the latch opening / closing electromagnetic relay 3 are electrically connected to the battery 2.

  In the reverse connection protection device for a vehicle of this embodiment, when the battery 2 is reversely connected, the above-described current path is formed, so that the electromagnetic relay driving means 5 and the microprocessor 7 do not operate, and these electromagnetic relays The driving means 5 and the microprocessor 7 operate only when the battery 2 is normally connected.

  By the way, in the vehicle reverse connection protection device of the present embodiment as described above, when the battery 2 is reversely connected, the reverse connection protection is appropriately performed. There is an aspect that is difficult to grasp.

  Therefore, in the reverse connection protection device for a vehicle according to the present embodiment, it is desirable to provide a light emitting diode 13 that emits light when the battery 2 is reversely connected upstream of the latch opening / closing electromagnetic relay 3. Specifically, the light emitting diode 13 has an anode terminal connected to the ground and a cathode terminal connected to the above-described current path formed when the battery 2 is reversely connected.

  Thereby, in the reverse connection protection device for a vehicle according to the present embodiment, when the battery 2 is reversely connected, the light emitting diode 13 can be caused to emit light as the current flows through the above-described current path. It is possible to appropriately notify that the battery 2 is in a protected state due to reverse connection, and to promote normal connection of the battery 2.

  As described in detail above, in the reverse connection protection device for a vehicle according to the present embodiment, the latch opening / closing electromagnetic relay 3 is provided between the battery 2 and the electric loads 14, 15. In parallel with the electromagnetic relay driving means 5 that drives the current through the exciting coil such that the current flows to the battery 2 through the exciting coil for driving the contact to the open side. The diode 11 is connected.

  Thereby, in this reverse connection protection device for a vehicle, when the battery 2 is reversely connected, a current flows from the diode 11 to the battery 2 via the exciting coil, and the contact of the latch opening / closing electromagnetic relay 3 is driven to the open side. Since the battery 2 and the electric loads 14 and 15 are electrically disconnected, the electric loads 14 and 15 are reliably protected when the battery 2 is reversely connected while realizing power saving, low heat generation, and low voltage drop. Can be planned.

  In particular, in this reverse connection protection device for a vehicle, when the exciting coil connected to the SET terminal is excited as a latch type relay, the contact is driven to the closed side, and the exciting coil connected to the RESET terminal is When the reverse connection of the battery 2 is eliminated by using the latch opening / closing electromagnetic relay 3 whose contact is driven to the open side when excited, the contact is automatically driven to the closing side, and the latch opening / closing type The electric loads 14 and 15 electrically connected to the downstream side of the electromagnetic relay 3 can be electrically connected to the battery 2, and the contacts can be freely opened and closed by controlling the electromagnetic relay driving means 4 and 5. It becomes possible to do.

  In addition, since the reverse connection protection device for a vehicle includes the light emitting diode 13 that emits light when the battery 2 is reversely connected, it can appropriately notify that the battery 2 is in a protected state due to the reverse connection of the battery 2 under an inexpensive configuration. The normal connection of the battery 2 can be promoted.

  Further, the reverse connection protection device for a vehicle includes a constant voltage power supply circuit 6 electrically connected to the upstream side of the latch opening / closing electromagnetic relay 3 and a microprocessor 7 driven by electric power supplied from the constant voltage power supply circuit 6. By supplying power to the microprocessor 7 from the constant voltage power supply circuit 6 without being affected by the opening / closing operation of the latch opening / closing electromagnetic relay 3, the electromagnetic relay driving means 4 and 5 are controlled. Can do.

(Second Embodiment)
Next, a reverse connection protection device for a vehicle according to a second embodiment of the present invention will be described with reference to FIG. This reverse connection protection device for a vehicle uses a latch opening type (normally closed) electromagnetic relay instead of the latch opening / closing type electromagnetic relay in the reverse connection protection device for a vehicle of the first embodiment. In addition, since the other structure in the reverse connection protection apparatus for vehicles of this embodiment is the same as that of 1st Embodiment mentioned above fundamentally, it is the same about the structure similar to 1st Embodiment below in the figure. The description which overlaps and abbreviate | omits the duplication description is demonstrated centering on the characteristic part of this embodiment.

  As shown in FIG. 2, the reverse connection protection device for a vehicle according to the present embodiment is configured by providing a latch opening type electromagnetic relay 21, which is a kind of latch type relay, between the battery 2 and the electric loads 14 and 15. . The latch open type electromagnetic relay 21 normally closes the contact, and drives the contact to the open side by current input to the exciting coil to mechanically maintain the open state.

  In the reverse connection protection device for a vehicle according to the present embodiment, as the latch opening type electromagnetic relay 21 is provided, a single unit configured by using a transistor or the like as electromagnetic relay driving means that drives the exciting coil by passing a current. It is only necessary to provide the electromagnetic relay driving means 22. Specifically, when the electromagnetic relay driving means 22 is configured using a transistor, the emitter terminal is connected to the ground, and the collector terminal is connected to the terminal of the latch-open electromagnetic relay 22.

  In the reverse connection protection device for a vehicle having such a latch opening type electromagnetic relay 21, when the battery 2 is normally connected, the contact of the latch opening type electromagnetic relay 21 is on the closing side, and the latch opening / closing is performed. The generator 1 and the electrical loads 14 and 15 that are electrically connected to the downstream side of the electromagnetic relay 21 are electrically connected to the battery 2.

  Further, in the reverse connection protection device for a vehicle according to the present embodiment, an electromagnetic relay drive connected to the open latching electromagnetic relay 21 in order to pass a current through the exciting coil of the open latching electromagnetic relay 21 when the battery 2 is reversely connected. A diode 11 is provided in parallel with the means 22. Specifically, the diode 11 has an anode terminal connected to the ground and a cathode terminal connected to the electromagnetic relay driving means 22. That is, the diode 11 is connected in parallel to the electromagnetic relay driving means 22 so that the direction in which the current flows to the battery 2 via the exciting coil of the latch-open electromagnetic relay 21 is the forward direction.

  Thereby, in the reverse connection protection device for a vehicle according to the present embodiment, when the battery 2 is reversely connected, the electromagnetic relay driving means 22 is turned on, so that the ground, the diode 11, the excitation coil of the latch open electromagnetic relay 21, A current path to the current breaker 12, the battery 2, and the ground is formed, and a current flows through the exciting coil of the latch-open electromagnetic relay 21, and accordingly, the contact is driven to the open side.

  Therefore, in the reverse connection protection device for a vehicle according to the present embodiment, when the battery 2 is reversely connected, the generator 1 and the electric loads 14 and 15 that are electrically connected to the downstream side of the latch-open electromagnetic relay 21 are connected to the battery 2. It will be electrically disconnected and protected against reverse connection.

  However, in the reverse connection protection device for a vehicle according to the present embodiment, when the reverse connection of the battery 2 is eliminated by using the latch opening type electromagnetic relay 21, the latch opening / closing type electromagnetic relay used in the first embodiment. As shown in FIG. 3, the contact is automatically returned to the contact recovery state, that is, the normal close state is not returned. Therefore, when the contact on the open side is returned to the close side, manual operation is required.

  As described in detail above, in the reverse connection protection device for a vehicle according to the present embodiment, the contact is normally closed as a latch-type relay, and the contact is driven to the open side by current input to the excitation coil. A latch opening type electromagnetic relay 21 that is mechanically kept open is used, and the cathode terminal of the diode 11 is connected to the electromagnetic relay driving means 22.

  Thereby, in this reverse connection protection device for a vehicle, when the battery 2 is reversely connected, a current flows from the diode 11 to the battery 2 via the exciting coil, and the contact of the latch opening type electromagnetic relay 21 is driven to the open side. Since the battery 2 and the electric loads 14 and 15 are electrically disconnected, the electric loads 14 and 15 are reliably protected when the battery 2 is reversely connected while realizing power saving, low heat generation, and low voltage drop. You can plan.

  In particular, in this reverse connection protection device for a vehicle, a latch opening type electromagnetic relay 21 which is less expensive than a latch opening / closing type electromagnetic relay is used as a latch type relay, and a single electromagnetic relay is employed by employing the latch opening type electromagnetic relay 21. Since only the drive means 22 is required, the number of parts can be reduced, and an inexpensive system can be constructed.

(Third embodiment)
Next, a reverse connection protection device for a vehicle according to a third embodiment of the present invention will be described with reference to FIG. This vehicle reverse connection protection device uses a diode built-in type electromagnetic relay drive means 31 in which these are integrated instead of the electromagnetic relay drive means 5 and the diode 10 in the vehicle reverse connection protection device of the first embodiment. is there. In addition, since the other structure in the reverse connection protection apparatus for vehicles of this embodiment is the same as that of 1st Embodiment mentioned above fundamentally, it is the same about the structure similar to 1st Embodiment below in the figure. The description which overlaps and abbreviate | omits the duplication description is demonstrated centering on the characteristic part of this embodiment.

  In the reverse connection protection device for a vehicle according to the present embodiment, instead of the electromagnetic relay driving means 5 and the diode 11 connected to the RESET terminal of the latch opening / closing electromagnetic relay 3, as shown in FIG. And a diode built-in electromagnetic relay driving means 31 in which the diode 11 is integrated.

  This diode built-in type electromagnetic relay driving means 31 is normally used for driving an inductive large current load such as a large current motor or a solenoid, and is configured by connecting a transistor and a diode in parallel with each other. In the reverse connection protection device for a vehicle, the diode built-in type electromagnetic relay driving means 31 is applied to a new application.

  Specifically, in the diode built-in type electromagnetic relay driving means 31, the emitter terminal of the transistor and the anode terminal of the diode are connected to each other, and these are connected to the ground, and the collector terminal of the transistor and the cathode terminal of the diode Are connected to each other, and these are connected to the RESET terminal of the latch opening / closing electromagnetic relay 3. Accordingly, in the latch opening / closing type electromagnetic relay 3, when the electromagnetic relay driving means 4 is turned on, a current flows through the SET terminal, and accordingly, the contact is driven to the closed side, while the diode built-in type electromagnetic relay driving. When the means 31 is turned on, a current flows through the RESET terminal, and accordingly, the contact is driven to the open side.

  Thus, in the reverse connection protection device for a vehicle according to the present embodiment, as an electromagnetic relay driving unit, one terminal of the transistor and the anode terminal of the diode are connected to each other, and the other terminal of the transistor and the diode are connected to each other. By using the diode built-in type driving means 31 that is connected to and integrated with the cathode terminal, the number of parts can be reduced, and an inexpensive system can be constructed.

(Fourth embodiment)
Next, a reverse connection protection device for a vehicle according to a fourth embodiment of the present invention will be described with reference to FIG. This vehicle reverse connection protection device uses an IPS (intelligent power switch) 41 with an overcurrent detection function in place of the electromagnetic relay drive means 5 and the diode 10 in the vehicle reverse connection protection device of the first embodiment. . In addition, since the other structure in the reverse connection protection apparatus for vehicles of this embodiment is the same as that of 1st Embodiment mentioned above fundamentally, it is the same about the structure similar to 1st Embodiment below in the figure. The description which overlaps and abbreviate | omits the duplication description is demonstrated centering on the characteristic part of this embodiment.

  In the reverse connection protection device for a vehicle according to the present embodiment, instead of the electromagnetic relay driving means 5 and the diode 11 connected to the RESET terminal of the latch opening / closing electromagnetic relay 3, as shown in FIG. Is provided. The IPS 41 with an overcurrent detection function can turn on the power MOS-FET by applying a reverse voltage to the overcurrent detection terminal, and is connected to the RESET terminal of the latch opening / closing electromagnetic relay 3. A diode is connected in parallel to the power MOS-FET formed.

  Specifically, the IPS 41 with an overcurrent detection function has an anode terminal connected to a gate terminal of a power MOS-FET whose source terminal is connected to the ground and whose drain terminal is connected to the RESET terminal of the latch opening / closing electromagnetic relay 3. Are connected to the cathode terminal of a diode connected to ground. Therefore, in the latch opening / closing type electromagnetic relay 3, when the electromagnetic relay driving means 4 is turned on, a current flows to the SET terminal, and accordingly, the contact is driven to the closed side, while the IPS 41 with an overcurrent detection function. When the power MOS-FET is turned on, a current flows through the RESET terminal, and accordingly, the contact is driven to the open side.

  Here, the IPS 41 with an overcurrent detection function is turned on by applying a reverse voltage to the gate terminal of the power MOS-FET via a diode. That is, in the reverse connection protection device for a vehicle according to the present embodiment, when the battery 2 is reversely connected, it is connected to the ground, the diode 41 of the IPS 41 with overcurrent detection function, the power MOS-FET, and the RESET terminal of the latch opening / closing electromagnetic relay 3. The exciting coil, the overcurrent breaker 12, the battery 2, and the current path to the ground are formed, and the contact of the latch opening / closing electromagnetic relay 3 is driven to the open side.

  Therefore, in the reverse connection protection device for a vehicle of this embodiment, when the battery 2 is reversely connected, the generator 1 and the electric loads 14 and 15 that are electrically connected to the downstream side of the latch opening / closing electromagnetic relay 3 are connected to the battery 2. It will be electrically disconnected and protected against reverse connection. Further, in the reverse connection protection device for a vehicle according to the present embodiment, when the reverse connection of the battery 2 is eliminated, a current flows through the excitation coil connected to the SET terminal of the latch opening / closing electromagnetic relay 3, so that The contact is driven to the closed side, and the generator 1 and the electrical loads 14 and 15 that are electrically connected to the downstream side of the latch opening / closing electromagnetic relay 3 are electrically connected to the battery 2.

  In the reverse connection protection device for a vehicle according to the present embodiment, when the battery 2 is reversely connected, the above-described current path is formed, so that the microprocessor 7 does not operate, and the microprocessor 7 is normal. It will only work when connected.

  As described in detail above, in the reverse connection protection device for a vehicle according to the present embodiment, as an electromagnetic relay driving means, a power MOS-FET that is turned on by applying a reverse voltage to an overcurrent detection terminal is used. IPS 41 with an overcurrent detection function in which a diode is connected in parallel is used.

  Thereby, in this reverse connection protection device for a vehicle, when the battery 2 is reversely connected, current flows from the diode 41 of the IPS 41 with an overcurrent detection function to the battery 2 via the exciting coil, and the latch opening / closing electromagnetic relay 3 The contact is driven to the open side, and the battery 2 and the electric loads 14 and 15 are electrically disconnected, so that the electric load when the battery 2 is reversely connected is realized while realizing power saving, low heat generation, and low voltage drop. 14 and 15 can be reliably protected.

(Fifth embodiment)
Next, a reverse connection protection device for a vehicle according to a fifth embodiment of the present invention will be described with reference to FIG. This vehicle reverse connection protection device uses the light emitting diode 51 instead of the diode 10 in the vehicle reverse connection protection device of the first embodiment, thereby eliminating the need for the separately provided light emitting diode 13. In addition, since the other structure in the reverse connection protection apparatus for vehicles of this embodiment is the same as that of 1st Embodiment mentioned above fundamentally, it is the same about the structure similar to 1st Embodiment below in the figure. The description which overlaps and abbreviate | omits the duplication description is demonstrated centering on the characteristic part of this embodiment.

  In the reverse connection protection device for a vehicle according to the present embodiment, as shown in FIG. 5, as a diode for flowing a current through the excitation coil connected to the RESET terminal of the latch opening / closing electromagnetic relay 3 when the battery 2 is reversely connected, A light emitting diode 51 that emits light when a voltage is applied is provided.

  Thereby, in the reverse connection protection device for a vehicle of this embodiment, when the battery 2 is reversely connected, the generator 1 and the electric loads 14 and 15 that are electrically connected to the downstream side of the latch opening / closing electromagnetic relay 3 are connected to the battery. 2 is electrically disconnected and protected from reverse connection, and the light emitting diode 51 emits light to appropriately notify that the battery 2 is in a protected state due to reverse connection. Can be encouraged.

  Thus, in the reverse connection protection device for a vehicle according to the present embodiment, the number of components can be reduced by using the light emitting diode 51 as a diode necessary for performing reverse connection protection using a latch-type relay. An inexpensive system can be constructed.

  The first to fifth embodiments described above are one application example of the present invention, and the present invention is not limited to the contents disclosed in the description of each of the above embodiments, and the technology according to the present invention. It goes without saying that various modifications can be made in a specific hardware configuration or the like as long as it does not deviate from the technical idea.

1 is a diagram showing a schematic circuit configuration of a reverse connection protection device for a vehicle as a first embodiment of the present invention. It is a figure which shows the schematic circuit structure of the reverse connection protection apparatus for vehicles as the 2nd Embodiment of this invention. It is a figure which shows schematic circuit structure of the reverse connection protection apparatus for vehicles as the 3rd Embodiment of this invention. It is a figure which shows the schematic circuit structure of the reverse connection protection apparatus for vehicles as the 4th Embodiment of this invention. It is a figure which shows the schematic circuit structure of the reverse connection protection apparatus for vehicles as the 5th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Generator 2 Battery 3 Latch opening / closing type electromagnetic relay 4, 5, 22 Electromagnetic relay drive means 6 Constant voltage power supply circuit 7 Microprocessor 8,9 Power supply control means 10 Transistor 11 Diode 12 Overcurrent circuit breaker 13,51 Light emitting diode 14, 15 Electric Load 21 Latch Open Type Electromagnetic Relay 31 Built-in Diode Type Electromagnetic Relay Drive 41 IPS with Overcurrent Detection Function

Claims (8)

In the reverse connection protection device for a vehicle that protects the electric load when a battery that supplies power to various electric loads mounted on the vehicle is connected in reverse polarity,
A latch-type relay provided between the battery and the electric load;
Driving means for driving the current by passing an electric current through an exciting coil for driving the contact of the latch type relay to the open side;
A reverse connection protection device for a vehicle, comprising: a diode connected in parallel to the drive means so that a direction in which a current flows to the battery via the excitation coil is a forward direction.   The vehicle reverse connection protection device according to claim 1, further comprising a light emitting unit that emits light when the battery is in reverse polarity contact.   The reverse connection protection device for a vehicle according to claim 2, wherein the diode is a light emitting diode as the light emitting means. When the first exciting coil connected to the first terminal is excited, the latch type relay drives the contact to the closed side, and the second exciting coil connected to the second terminal This is a latching electromagnetic relay that drives the contact to the open side when energized.
2. The reverse connection protection device for a vehicle according to claim 1, wherein a cathode terminal of the diode is connected to the driving means. The latch-type relay is a latch-open type electromagnetic relay that normally closes the contact, drives the contact to the open side by current input to the exciting coil, and mechanically maintains the open state.
2. The reverse connection protection device for a vehicle according to claim 1, wherein a cathode terminal of the diode is connected to the driving means.   The driving means includes a diode built-in type driving in which one terminal of the transistor and the anode terminal of the diode are connected to each other, and the other terminal of the transistor and the cathode terminal of the diode are connected to each other. The vehicle reverse connection protection device according to claim 1, wherein the vehicle reverse connection protection device is a means.   The drive means is an intelligent power switch in which the diode is connected in parallel to a power MOS-FET that is turned on by applying a reverse voltage to a terminal for detecting overcurrent. The reverse connection protection apparatus for vehicles according to 1. A constant voltage power circuit electrically connected to the upstream side of the latch-type relay;
The vehicle reverse connection protection device according to claim 1, further comprising a control unit that is driven by electric power supplied from the constant voltage power supply circuit and controls the driving unit.

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