JP2005210797A - Wire connecting box with safety function, safety device for power supply circuit, and safety system of power supply circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure safety for the installation and removal of the wire connecting part of a power supply line. <P>SOLUTION: This power supply circuit comprises: a high-voltage battery B1; a low-voltage battery B2; a high-voltage power supply line 205; a low-voltage power supply line 206; and a DC/DC converter 200 that converts a high voltage at the high-voltage power supply line 205 side to a low voltage at the low-voltage power supply line 206 side. In the power supply circuit, a safety device 100 is inserted between the wire connecting parts of the power supply line. The safety device 100 comprises: a first terminal 101 at the battery side; a second terminal 102 at the DC/DC converter side; a first switch SW1 that is inserted above a conduction passage 103 that connects both the terminals; a low conductive member 104; a control circuit 106 that turns on the first switch SW1 by being fed with power via the first terminal; and a short-circuit conductor 120 that is detachably installed between both ends of the low-conductive member 104. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a connection box with a safety function mainly applied to a power supply circuit for a vehicle, a safety device for a power supply circuit, and a safety system for a power supply circuit including the safety device.

  2. Description of the Related Art In recent years, for example, in a power supply circuit for a vehicle, development for improving fuel efficiency by increasing a power supply voltage and performing efficient load driving has been advanced. As such a power supply circuit, a high voltage (36V) battery is used as the main power supply, and the current low voltage (12V) driving load power supply voltage is supplied by stepping down 36V to 12V by a DC / DC converter. Has been. In such a power supply circuit, the main power supply and the driving load are shut off by a breaker device or the like during maintenance or the like (see Patent Document 1).

  FIG. 14 is a configuration diagram of such a conventional power supply circuit.

In the figure, 801 is a motor generator, 802 is an AC / DC converter that converts electric power generated by the motor generator 801 into direct current, 803 is a high voltage (36V) drive load, and B1 is for supplying power to the high voltage drive load 803. A high voltage (36V) battery, 810 is a positive terminal of the high voltage battery B1, a high voltage power line connected to the AC / DC converter 802 and the drive load 803, 804 is a low voltage (12V) drive load, and B2 is a low voltage. A low voltage (12V) battery for supplying power to the drive load, 820 is a low voltage power line connected to the positive terminal of the low voltage battery B2 and the drive load 804, and 200 is a high voltage power line 810 and a low voltage power line 820. The DC / DC converter is connected between the two and converts a high voltage on the high voltage power supply line 810 side into a low voltage on the low voltage power supply line 820 side. , 500 is a terminal box.
Japanese Patent Laid-Open No. 9-223439

  By the way, in this type of power supply circuit, for example, an arc is generated at the connection site when connecting / disconnecting the connection portions of the power supply wires 810 and 820 connected from the DC / DC converter 200 to the batteries (36V, 12V) B1 and B2. There is a case. In particular, the high voltage (36V) side electric wire 810 is dangerous because it is at a high voltage during installation / removal and maintenance.

  An arc is generated in the following case.

  (1) When the connection part is disconnected in a voltage application state (load operation state), an arc is generated when the connection part is connected in a dischargeable state. This arc increases with increasing voltage and increases the risk. In particular, an arc is generated when the terminals of the batteries B1 and B2 and the terminals of the DC / DC converter 200 are attached / detached.

  (2) When the DC / DC converter 200 is left for a long time or when the DC / DC converter 200 is operated for the first time, the capacitor provided in the DC / DC converter 200 is in an empty state ( Therefore, when the power supply lines 810 and 820 are connected, the larger the batteries B1 and B2 are fully charged, the larger current flows from the batteries B1 and B2 to the capacitors. An arc occurs when the terminals of lines 810 and 820 are connected.

  (3) In the power supply circuit described above, when the DC / DC converter 200 is in a state of being operated even once, since the electric charge is stored in the capacitor provided in the DC / DC converter 200, the power supply When the wires 810 and 820 are removed, if the terminals of the power wires 810 and 820 connected to the positive terminal of the DC / DC converter 200 come into contact with the vehicle body or other metal, they are short-circuited to cause an arc. Occur.

  In the state of (3) above, when the power supply line 810 is first attached to the high voltage battery B1, an arc is generated when the power supply line 810 is attached to the DC / DC converter 200. When the power supply line 810 is attached to the DC / DC converter 200 first, an arc is generated when the power supply line 810 is attached to the high voltage battery B1.

  Further, in order to avoid the occurrence of arc in the case of (3), it is necessary to work according to a predetermined procedure, but there is a problem that there is a possibility of mistakes and the work is difficult to do.

  In consideration of the above circumstances, the present invention is a connection box with a safety function, a safety device for a power supply circuit, and a power supply using the safety device, which can safely connect and disconnect a power supply wire by a simple procedure. An object is to provide a circuit safety system.

  The invention of claim 1 is a connection box with a safety function that is inserted into a connection part of a power supply line, and has an insulation box having a pair of terminal accommodating parts that can be separated from each other to accommodate terminals, and the insulation box A pair of low-conductivity members that are disposed between the pair of terminal accommodating portions, and in which the terminals contact and conduct at both ends when the terminals are accommodated in the respective terminal accommodating portions, and a pair that respectively contact and conduct to both ends of the low-conducting member A short-circuit conductor that is detachably mounted between the terminals in order to short-circuit the terminals, and an insulating cover that is detachably mounted to the insulation box so as to hold the short-circuit conductor and close the opening of the insulation box; , Provided.

  When connecting a power supply line using this connection box, first, both terminals attached to each end portion to be connected to the power supply line are respectively accommodated in the terminal accommodating portion of the insulating box. If it does so, a temporary conduction state will be ensured between both terminals via the low electroconductive member arrange | positioned in the insulation box. Thereafter, an insulating cover is attached to the insulating box to attach the short-circuit conductor between both terminals. Then, since the resistance value of the short-circuit conductor is much smaller than that of the low-conductivity member, the original (normal) conduction state through the short-circuit conductor is ensured between both terminals. In this way, at the beginning of the connection, a temporary conduction state in which only a weak current flows first can be created, so that the generation of an arc at the initial stage of the connection can be suppressed. In addition, since the provisional conduction state is secured and the original conduction state is secured by mounting the short-circuit conductor, it is possible to suppress the occurrence of arcing at that stage.

  When disconnecting the wires, remove the insulating cover and remove the short-circuit conductor from between both terminals. Then, at that stage, a state in which a current flows through the low conductive member instead of the short-circuit conductor is ensured, so that there is no possibility that an arc is generated when the short-circuit conductor is removed. After that, even if the terminal is removed, only a weak current flows through the low conductive member at that stage, so that no arc is generated.

  The invention according to claim 2 is the connection box with safety function according to claim 1, wherein the short-circuit conductor has an engagement protrusion inserted into an engagement hole formed in each terminal, and a flat plate portion of each terminal. The contact box is provided with an abutting surface contact portion, and the insulating box is provided with an engaging groove into which a tip of the engaging protrusion penetrating the engaging hole of the terminal is fitted.

  In the case of this connection box, when the short-circuit conductor is mounted between both terminals, the engagement protrusion of the short-circuit conductor is inserted into the engagement hole of the terminal, so that the engagement between the two is reliably performed. Further, since the surface contact portion of the short-circuit conductor is in contact with the flat plate portion of the terminal, conduction is ensured, so that a connection state that can withstand a large current is obtained. In addition, since the tip of the engagement protrusion penetrating the engagement hole of the terminal fits into the engagement groove provided in the insulating box, the terminal and the short-circuit conductor are more firmly coupled.

  According to a third aspect of the present invention, there is provided a safety device for a power supply circuit inserted and connected between connection portions of a power supply line connected to a positive terminal of a battery, wherein the first connection portion is connected to a connection portion on the positive terminal side of the battery. A second connection portion connected to the connection portion on the opposite side, a high-resistance low-conductivity member inserted on the conduction path connecting the first connection portion and the second connection portion, and the conduction path A normally-open first switch that is inserted closer to the first connection portion than the low-conductivity member to open and close the conduction path, control means having a function of controlling the opening and closing of the first switch, A short-circuit conductor that is detachably mounted to short-circuit both ends of the conductive member, and when the control means is turned on by being supplied with power from the battery via the first connection portion. , Closing the first switch, and A function of ensuring conduction of a conduction path connecting two connecting parts, and a function of opening the first switch when the short-circuit conductor is removed from a state where both ends of the low-conductive member are short-circuited. It is characterized by having.

  When connecting a power line using this safety device, connect the positive terminal side connection part of the battery to the first connection part, and connect the opposite side connection part (load side or DC / DC converter side, for example). The connection part) is connected to the second connection part. Then, the electric power from the battery is supplied via the first connection portion, so that the control means is turned on, the first switch is closed (ON), and the low conductivity is established between the first and second connection portions. A temporary conduction state is ensured through the sex member. Next, when a short-circuit conductor is attached and both ends of the low-conductive member are short-circuited, the resistance value of the short-circuit conductor is much smaller than that of the low-conductive member, so that the first and second connection portions are connected. The original (normal) conduction state through the short-circuit conductor is ensured.

  In this way, since the first switch keeps the conduction path cut off during connection, there is no possibility that an arc will occur between the terminals to be connected. Further, when the first switch is closed (ON) by the command of the control means, since a weak current flows only through the low conductive member as described above, the first switch is connected between the switch contacts. There is no risk of arcing. Therefore, there is no risk of arcing when the short-circuit conductor is attached.

  Further, when disconnecting the power supply line, since a state in which a current flows through the low-conductive member instead is secured at the stage of removing the short-circuit conductor, there is no possibility that an arc is generated when the short-circuit conductor is removed. After that, the first switch is opened (OFF), the conduction between the first connection end and the second connection end is released, and in this state, the battery is removed from the first connection end side, so that the arc is It does not occur.

  The invention according to claim 4 is the safety device for the power supply circuit according to claim 3, wherein the control means detects the voltage across the low-conductive member after opening the first switch, It has a function of outputting a signal permitting the mounting of the short-circuit conductor when the voltage between both ends becomes a predetermined value or less.

  In the case of this safety device, when the voltage at both ends of the low-conductivity member falls below a predetermined value, a signal permitting the installation of the short-circuit conductor is output. Connection work can be performed.

  For example, when the second connection portion is connected to a DC / DC converter in which the amount of power stored in the built-in capacitor is empty, the voltage at both ends is large at the beginning of the connection, so a slightly larger current flows through the low conductive member. As the battery is charged, the voltage across the low conductive member decreases. Therefore, when the voltage becomes a predetermined value or less, a signal for prompting the mounting of the short-circuit conductor is output, so that the short-circuit conductor can be mounted safely.

  According to a fifth aspect of the present invention, in the safety device for a power circuit according to the third or fourth aspect, a ground line that is grounded via an arc prevention resistor is connected to the second connecting portion, and the ground line In addition, a normally open second switch for opening and closing the ground wire is inserted, and the control means removes the first short circuit conductor that has shorted both ends of the low conductive member. It has a function of closing the second switch after opening the switch.

  In the case of this safety device, there is a configuration in which the second connection portion is appropriately grounded by closing (ON) the second switch after the first switch is opened (OFF) with the removal of the short-circuit conductor. Therefore, for example, when the second connection portion is connected to the DC / DC converter, the connection can be safely removed.

  That is, when the second connection portion is connected to the DC / DC converter, if a large amount of electricity is stored in the capacitor built in the DC / DC converter, remove the connection portion on the second connection portion side as it is. Then, since the second connection portion side is at a high voltage, there is a possibility that an arc may occur when the removed terminal or the like comes into contact with another metal member. After 1 switch is opened, the electricity accumulated in the capacitor of the DC / DC converter is positively discharged to the ground through the second connection part. Therefore, by working after sufficiently discharging, the DC / DC converter side The connection part can be removed safely.

  The invention according to claim 6 is the safety device for the power supply circuit according to claim 5, wherein the control means detects the voltage on the second connection portion side, and the voltage on the second connection portion side is not more than a predetermined value. When this happens, it has a function of outputting a signal notifying the end of the discharge through the second connection portion and opening the second switch.

  In the case of this safety device, the connection can be safely disconnected by removing the connection part on the second connection part side based on a signal notifying the end of the discharge.

  The invention according to claim 7 is the safety device for the power circuit according to claim 5 or 6, wherein the power line connected to the positive terminal of the battery connects between the positive terminal of the battery and the DC / DC converter. It is a line.

  When this safety device is used, the connection between the battery and the DC / DC converter can be connected and disconnected while preventing arcing.

  The invention of claim 8 includes a high voltage battery for supplying power to the high voltage load, a low voltage battery for supplying power to the low voltage load, a high voltage power supply line connected to the positive terminal of the high voltage battery, Connected between the low voltage power line connected to the positive terminal of the voltage battery and between the high voltage power line and the low voltage power line, and converts the high voltage on the high voltage power line side to the low voltage on the low voltage power line side In the power supply circuit having a DC / DC converter, between the connection portions of the high voltage power supply line connecting the plus terminal of the high voltage battery and the primary plus terminal of the DC / DC converter, and the secondary of the DC / DC converter The safety device according to claim 5 or 6, wherein the safety device according to claim 5 or 6 is inserted and connected between at least one of the connection portions of the low-voltage power supply line connecting the side plus terminal and the plus terminal of the low-voltage battery.

  In this safety system, when the safety device described above is connected between the DC / DC converter and the battery, the control means is turned on when power is supplied from the battery, and the first switch is then closed by a signal from the control means. (ON) and the conduction path becomes a conduction state. Before the short-circuit conductor is mounted, the battery and the DC / DC converter are temporarily connected via the low-conductive member, and several mA to several tens mA from the battery to the capacitor inside the DC / DC converter. A small amount of current flows. For this reason, an arc does not occur at the time of connection.

  When the voltage at both ends of the low conductive member becomes equal, the battery and the DC / DC converter can be fully connected via the shorted conductor by attaching the short circuit conductor between both ends of the low conductive member. it can. In this case, the control means monitors the voltage at both ends of the low-conductivity member, and when both voltages are the same, it is safe to attach the short-circuit conductor by turning on the indicator lamp and notifying that it is safe. Can do. By mounting the short-circuit conductor in this way, the current hardly flows to the low-conductive member having a high resistance value, but flows from the first connection portion to the second connection portion via the short-circuit conductor, and the original connection A state is obtained.

  On the other hand, when removing the connection, the short-circuit conductor is first removed. If it does so, a control means will detect removal of a short circuit conductor, will open a 1st switch (OFF), and will interrupt conduction with the 1st connecting end and the 2nd connecting end. Therefore, the battery and the DC / DC converter are surely cut off. Here, once the first switch is opened (OFF), it does not close again (ON) unless it is in the initial connection start state, so it is safe to re-install the short-circuit conductor by mistake.

  After the short-circuit conductor is removed and the first switch is opened (OFF), the ground wire is opened by closing (ON) the second switch. Therefore, electricity accumulated in the capacitor inside the DC / DC converter is discharged to the ground through the arc-preventing resistor dedicated to the capacitor. Also in this case, since the discharge is performed with a very small amount of current, no arc is generated.

  When it is confirmed that the battery has been sufficiently discharged, the power line is removed. Thereby, for example, it is possible to prevent an arc generated when the power supply line is removed during maintenance.

  As explained above, according to the connection box with a safety function of the invention of claim 1, a temporary conductive state in which only a weak current flows is created by the low conductive member before the short circuit conductor is initially attached. Therefore, it is possible to suppress the occurrence of arc at the initial stage of connection. Moreover, since the original conductive state is ensured by mounting the short-circuit conductor after the temporary conductive state is secured by the low conductive member, the occurrence of an arc at that stage can be suppressed. Also, when removing the connection, it is possible to secure a state in which a weak current flows through the low-conductive member instead of the short-circuit conductor by removing the short-circuit conductor from both terminals. Occurrence can be prevented. Further, even if the connection is removed after that, since only a weak current flows through the low conductive member at that stage, the generation of an arc can be prevented. Therefore, it is possible to effectively prevent the occurrence of an arc when the power supply line is attached and detached, and the work safety can be improved.

  According to the connection box with safety function of the invention of claim 2, when the short-circuit conductor is mounted between the two terminals, the engagement protrusion of the short-circuit conductor is inserted into the engagement hole of the terminal. Can be performed reliably. In addition, since the surface contact portion of the short-circuit conductor is brought into contact with the flat plate portion of the terminal, high conductivity can be ensured and a connection state that can withstand a large current can be obtained. In addition, since the tip of the engagement protrusion that penetrates the engagement hole of the terminal is fitted into the engagement groove on the insulating box side, the connection between the terminal and the short-circuit conductor can be performed more firmly, and the connection reliability Can be increased.

  According to the safety device for a power supply circuit of the invention of claim 3, since the continuity is cut off at the time of connection by the built-in first switch, an arc generated between the terminals to be connected can be prevented. In addition, when the first switch is closed (ON) by a command from the control means, an arc is generated at the switch contact because only a weak current flows through the low conductive member. Nor. Therefore, the generation of an arc can be prevented even when the short-circuit conductor is attached in order to secure the original conduction state. Further, when the power supply line is removed, a state in which a current flows through the low-conductive member instead at the stage where the short-circuit conductor is removed is secured, so that an arc can be prevented from being generated when the short-circuit conductor is removed. After that, the first switch is opened (OFF), the conduction between the first connection part and the second connection part is released, and in this state, the battery is removed from the first connection part side. Occurrence can be reliably prevented.

  According to the safety device for a power supply circuit of the invention of claim 4, when the voltage across the low conductive member becomes a predetermined value or less by the control means, a signal for permitting the mounting of the short-circuit conductor is output. Therefore, the connection work can be performed safely by attaching the short-circuit conductor at that timing.

  According to the safety device for a power supply circuit of the fifth aspect of the present invention, the second switch is closed (ON) after the first switch is opened (OFF) with the removal of the short-circuit conductor. Since the connection portion is appropriately grounded, for example, when the second connection portion is connected to the DC / DC converter, the electricity of the capacitor built in the DC / DC converter is reliably discharged. Later, the connection can be safely removed and maintenance can be performed.

  According to the safety device for the power supply circuit of the sixth aspect of the invention, since the control means generates the signal notifying the end of the discharge of the capacitor of the DC / DC converter, the second connecting portion side is based on the signal. The connection can be safely disconnected by removing the connection part.

  According to the seventh aspect of the present invention, since the power line connected to the positive terminal of the battery is connected to the DC / DC converter via the safety device, the connection between the battery and the DC / DC converter is prevented from generating an arc. While connecting and disconnecting.

  According to the power circuit safety system of the eighth aspect of the present invention, it is possible to avoid the occurrence of an arc that occurs when a power supply line is attached or removed by simply performing a simple operation of attaching or removing a short-circuit conductor. Can work on. In particular, when the power supply component is maintained, the power supply from the battery can be cut off by removing the short-circuit member before the work, so that the work can be performed safely on the high voltage side. In addition, when the operation is suspended for a long period of time, the battery can be prevented from rising simply by removing the short-circuit conductor. Furthermore, since the control circuit provided in the safety device exhibits a predetermined function, the work can be safely performed with a simple procedure.

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

  1 to 6 are diagrams showing the configuration of a connection box with a safety device, FIG. 7 is a configuration diagram of a safety device for a power circuit, and FIGS. 8 to 12 are safety diagrams of a power circuit configured using the safety device of FIG. It is a block diagram of a system.

《Connection box with safety function》
First, the connection box with a safety device shown in FIGS. 1 to 6 will be described.

  1 is a perspective view showing a state of a connection box before connection, FIG. 2 is a cross-sectional view thereof, FIG. 3 is a perspective view showing a state of a connection box with terminals attached, FIG. 4 is a cross-sectional view thereof, and FIG. The perspective view which shows the state of the connection box at the time of completion | finish of a connection, FIG. 6 is the same sectional drawing.

  The configuration of the connection box will be described with reference to FIGS.

  The connection box 10 includes a fixed box 10A and a service plug 10B that is detachably mounted thereon.

  The fixed-side box 10A is disposed between the pair of terminal accommodating portions 15A and 15B in the center of the insulating box 11 having the pair of terminal accommodating portions 15A and 15B, and the low-conductive member 13 having a rectangular flat plate shape is disposed. It is installed and fixed.

  The low conductive member 13 is a resistor for preventing arcing, and has a resistance value set to several kΩ to several tens kΩ so that only a small amount of electricity can flow.

  Each terminal accommodating portion 15A, 15B is a portion that accommodates the terminals 21A, 21B attached to the ends of the power supply lines 20A, 20B to be connected, and in a state of receiving the terminals 21A, 21B inserted from above, Female screw holes 16 for fixing the terminals 21A and 21B with screws 28 and locking ribs 17 for positioning the terminals 21A and 21B are provided. Further, at both ends of the insulating box 11, there are provided wire lead-out grooves 18 for drawing out the power supply lines 20A and 20B.

  The terminals 21A and 21B attached to the ends of the power supply lines 20A and 20B have a front flat plate portion 22 and a rear wire crimping portion 23. An insertion hole 24 for passing the screw 28 is provided, an engagement hole 25 is provided on the front side of the insertion hole 24, and the engaging ribs 17 are engaged on both side edges on the rear side of the insertion hole 24. A notch 26 is provided. The locking rib 17 is divided on both sides so as to be engaged with the engagement notch 26, and has a space 17a in which the terminals 21A and 21B are fitted in the intermediate portion.

  Then, when the terminals 21A and 21B are put in the terminal accommodating portions 15A and 15B of the insulating box 11, the engagement notches 26 of the terminals 21A and 21B are engaged with the locking ribs 17, thereby positioning the terminals 21A and 21B. Can be temporarily locked.

  One service plug 10B has a structure in which a metal short-circuit conductor 14 is attached to the inner surface (lower surface) of an insulating cover 12 having electrical insulation. The insulating cover 12 is detachably attached to the insulating box 11 so as to close the upper surface opening of the insulating box 11, and has a planar shape matching the upper surface opening of the insulating box 11.

  The insulating cover 12 is provided with a convex portion 12b that can be grasped by hand on the upper surface of the central wide flat plate portion 12a. The narrow width that closes the upper surface of the wire lead-out groove 18 of the insulating box 11 is formed on the left and right ends of the wide flat plate portion 12a. A flat plate portion 12c is provided, and ribs 12d that overlap the locking ribs 17 on the insulating box 11 side and protrusions 12e that fit into the voids 17a of the locking ribs 17 are provided on the left and right ends of the lower surface of the wide flat plate portion 12a. It has been.

  A short-circuit conductor 14 attached to the lower surface of the insulating cover 12 is detachably mounted between the terminals 21A and 21B in order to short-circuit the pair of terminals 21A and 21B connected to both ends of the low-conductivity member 14, respectively. It is comprised by the good conductor which can flow a big electric current.

  The short-circuit conductor 14 includes a flat surface contact portion 14a that abuts against the flat plate portion 22 of both terminals 21A and 21B in a form straddling both terminals 21A and 21B, and an engaging protrusion 14b that protrudes downward at both ends thereof. Have The engagement protrusion 14b is a portion inserted into the engagement hole 25 of the terminals 21A and 21B, and is formed in the same shape on the left and right so that it can be attached in either direction.

  Further, a connecting member having an engaging groove 19a for fitting the tip of the engaging protrusion 14b penetrating the engaging hole 25 of the terminals 21A and 21B at the bottom of each terminal accommodating portion 15A and 15B of the insulating box 11. 19 is fixed.

  Next, a procedure for connecting the power supply lines 20A and 20B using the connection box 10 having such a structure will be described.

  When connecting the power supply lines 20A and 20B using the connection box 10, first, the two terminals 21A and 21B attached to the ends of the power supply lines 20A and 20B to be connected are shown in FIGS. Are accommodated in the terminal accommodating portions 15A and 15B of the insulating box 11 of the fixed side box 10A, respectively.

  That is, the screw insertion holes 24 are aligned with the female screw holes 16, and the positioning notches 26 provided on both side edges of the terminals 21A and 21B are engaged with the locking ribs 17, and the terminals 21A and 21B are placed in the voids 17a. Fit. In this state, the terminals 21A and 21B are positioned and temporarily locked.

  Next, the terminals 21 </ b> A and 21 </ b> B are permanently fixed by tightening the screws 28 into the female screw holes 16 through the insertion holes 25. Then, the flat plate portions 22 of the terminals 21A and 21B are in surface contact with the upper surface of the low conductive member 14 disposed in the insulating box 11, and the low conductive member 14 is interposed between the terminals 21A and 21B. A temporary conduction state is ensured. In this state, the terminals 21A and 21B of the power lines 20A and 20B arranged from the left and right are held at positions where they cannot be directly contacted.

  Thereafter, as shown in FIGS. 5 and 6, the service plug 10B is mounted on the fixed side box 10A. If it does so, the short circuit conductor 14 will be mounted | worn in the form straddling between both terminal 21A, 21B. That is, the engagement protrusion 14b of the short-circuit conductor 14 is inserted into the engagement hole 25 of the terminals 21A and 21B, and the tip of the engagement protrusion 14b passing through the engagement hole 25 of the terminals 21A and 21B is the bottom of the insulating box 11. It fits in the engaging groove 19a of the connecting member 19 provided in the. Thereby, the terminals 21A and 21B and the short-circuit conductor 14 are firmly coupled. Further, the surface contact portion 14a of the short-circuit conductor 14 is in pressure contact with the upper surface of the flat plate portion 22 of the terminals 21A and 21B, so that both the terminals 21A and 21B are reliably contacted and connected by the short-circuit conductor 14.

  In this case, since the resistance value of the short-circuit conductor 14 is set to be remarkably smaller than that of the low-conductive member 13, the original (normal) conduction state through the short-circuit conductor 14 is between the terminals 21A and 21B. Secured.

  In this way, since the provisional conduction state in which only a weak current flows first is created through the low conductive member 13 at the beginning of the connection, the generation of an arc at the initial stage of the connection can be suppressed. Moreover, since the original conduction | electrical_connection state is ensured by mounting | wearing with the short-circuit conductor 14, after ensuring a temporary conduction | electrical_connection state, generation | occurrence | production of the arc at that stage can also be suppressed.

  Next, when disconnecting the wiring, first, the service plug 10B having a lid function is removed, and the short-circuit conductor 14 is pulled away from between both terminals 21A and 21B. Then, at that stage, a state in which a weak current flows between the terminals 21A and 21B through the low conductive member 13 instead of the short-circuit conductor 14 is ensured, so that there is no possibility of an arc occurring when the short-circuit conductor 14 is removed. . After that, even if the terminals 21A and 21B are removed, only a weak current flows through the low conductive member 13 at that stage, so that no arc is generated.

《Safety device for power circuit》
Next, a safety device for a power supply circuit will be described with reference to FIG.

  The safety device 100 is inserted and connected between the connection portions 201 and 202 of the power line 205 connected to the positive terminal of the battery B, and is connected to the connection portion 201 on the positive terminal side of the battery B (first terminal ( The first connection portion 101 is inserted into the second terminal (second connection portion) 102 connected to the connection portion 202 on the opposite side, and the conduction path 103 connecting the first terminal 101 and the second terminal 102. A high-resistance low-conductivity member 104; a normally-open first switch SW1 that is inserted closer to the first terminal 101 than the low-conductivity member 104 on the conduction path 103 to open and close the conduction path 103; A control circuit (control means) 106 having a function of controlling the opening and closing of the switch SW1 and a short-circuit conductor 120 that is detachably mounted to short-circuit both ends of the low-conductive member 104 are provided. A DC / DC converter 200 is connected to the connection portion 202 connected to the second terminal 102.

  The second terminal 102 is connected to a ground line 107 that is grounded via an arc prevention resistor 108. The normally open type second switch SW2 that opens and closes the ground line 107 is connected to the ground line 107. Has been inserted. The ground wire 107 is connected to, for example, a vehicle body by a ground terminal 113.

  The control circuit 106 performs the following functions.

  (1) First, the power is supplied from the battery B through the first terminal 101, so that the control circuit 106 is turned on.

  (2) Thereafter, the first switch SW1 is turned on (closed), and the conduction of the conduction path 103 connecting the first terminal 101 and the second terminal 102 is ensured.

  (3) Next, the voltage between both ends of the low conductive member 104 is monitored, and when the voltage between both ends becomes a predetermined value or less, a signal permitting the mounting of the short-circuit conductor 120 is output. For example, the display lamp is turned on by the signal to notify the operator that the short-circuit conductor 120 is ready to be attached.

  (4) Next, when the short-circuit conductor 120 is removed from the state where it is mounted to short-circuit both ends of the low-conductive member 104, the first switch SW1 is turned off (opened).

  (5) Further, after the first switch SW1 is turned off, the second switch SW2 is turned on (closed), and the ground line 107 is turned on.

  (6) Next, the voltage on the second terminal 102 side is monitored, and when the voltage on the second terminal 102 side becomes equal to or lower than a predetermined value, a signal notifying the end of the discharge through the second terminal 102 is output. For example, the display lamp is turned on by the signal to notify the operator of the end of the discharge.

  (7) Then, the ground switch 107 is returned to a non-conductive state by turning off the second switch SW2.

  In the safety device 100, the portion including the low conductive member 104 and the short-circuit conductor 120 can be configured by the connection box 10 shown in FIGS. 1 to 6. In that case, the portion including the short-circuit conductor 120 corresponds to the service plug 10 </ b> B of the connection box 10. Further, the portion including the low conductive member 104 has a configuration on the fixed side box 10A side. At this time, other parts of the safety device 100 may be provided outside the fixed side box 10A, but may be provided inside the fixed side box 10A.

<Safety system for power supply circuit>
Next, a safety system for a power supply circuit incorporating the safety device 100 will be described with reference to FIGS. The effect of the safety device 100 of FIG. 7 will be clarified in the description of this safety system.

  The power supply circuit shown in FIGS. 8 to 12 includes a high voltage battery B1 for supplying power to the high voltage load, a low voltage battery B2 for supplying power to the low voltage load, and the high voltage battery B1 via the terminal box 500 and the like. The high voltage power line 201 connected to the plus terminal of the low voltage battery B2, the low voltage power line 206 connected to the plus terminal of the low voltage battery B2, and the high voltage power line 205 and the low voltage power line 206 are connected to each other. And a DC / DC converter 200 that converts a high voltage on the voltage power supply line 205 side to a low voltage on the low voltage power supply line 206 side.

  The safety device 100 includes the high-voltage power supply line 205 connecting the plus terminal of the high-voltage battery B1 and the primary plus terminal 210 of the DC / DC converter 200, and the secondary of the DC / DC converter 200. The side plus terminal 220 and the plus terminal of the low voltage battery B2 are respectively inserted and connected between the connection portions of the low voltage power supply line 206.

  The DC / DC converter 200 includes a transistor 231 and a coil 232 between positive and negative terminals 210 and 220 on the primary side, and capacitors 241 and 242 are connected between the positive terminal 210 and the negative terminals 212 and 222, respectively. A diode 245 is connected between the connection point of the transistor 231 and the coil 232 and the negative terminals 212 and 222, and charges are stored in the capacitors 241 and 242 during operation.

  FIG. 8 shows a state before connection. That is, the DC / DC converter 200, the batteries B1 and B2, and the safety device 100 are not connected.

  Here, it is assumed that the control circuit 106, the switches SW1 and SW2, and the arm prevention resistor 108 are arranged in the fixing box 10A constituting the connection box 10 described above.

  At this stage, since the control circuit 106 is not supplied with power, it is in an OFF state. Accordingly, both the first switch SW1 and the second switch SW2 are in an OFF state (a state in which the switch is open). In the initial state, the capacitor in the DC / DC converter 200 is 0 V (empty). Further, the service plug 10B (short-circuit conductor 120) is removed from the fixed side box 10A.

  FIG. 9 shows a state when the DC / DC converter 200 and the batteries B <b> 1 and B <b> 2 are connected via the safety device 100. That is, the fixed side box 10A is inserted between the power supply lines 205 and 206 connected to the batteries B1 and B2 and the DC / DC converter 200. The black thick line in the figure indicates the current flow at the beginning of the connection.

  Note that the power supply voltage range of the internal control circuit 106 is set between 12V and 36V so that the safety device 100 (particularly the fixed side box 10A) can be attached to both the high voltage side and the low voltage side. Yes.

  When using this safety device 100 and connecting the power lines 205 and 206 connected to the positive terminals of the batteries B1 and B2 to the positive terminals 210 and 220 of the DC / DC converter 100, the positive terminals of the batteries B1 and B2 The side connection parts 201 and 207 are connected to the first terminal 101 of the safety device 100, and the plus terminals 210 and 220 of the DC / DC converter 200 are connected to the second terminal 102 of the safety device 100. Thereby, the DC / DC converter 200 and the batteries B1 and B2 are connected via the safety device 100.

  When connected in this way, the power from the batteries B1 and B2 is supplied via the first terminal 101, whereby the control circuit 106 in the safety device 100 is turned on. When the control circuit 106 is turned on, first, the first switch SW1 is turned on to make the first terminal 101 and the second terminal 102 conductive. Accordingly, the batteries B1 and B2 and the DC / DC converter 200 are temporarily brought into conduction through the high-resistance low-conductive member 104, and are transferred from the batteries B1 and B2 to the capacitors 241 and 242 in the DC / DC converter 200. A small amount of current of about several mA to several tens mA flows.

  Thus, at the beginning of the connection, the first switch SW1 keeps the conduction path 103 in a disconnected state, so there is no possibility that an arc will occur between the terminals to be connected. In addition, when the first switch SW1 is turned on by a command from the control circuit 106, a weak current flows through the low conductive member 104, so that an arc may occur between the contact points of the switch. Absent.

  When the batteries B1 and B2 and the DC / DC converter 200 are connected via the low conductive member 104, the voltage between the both ends of the low conductive member 104 is slightly higher at the beginning of the connection. As the capacitors 241 and 242 are charged, the voltage across the low conductive member 104 decreases. The control circuit 106 monitors the voltage between both ends of the low-conductive member 104, and when both voltages become substantially the same, for example, a display lamp is turned on to inform the operator that it is safe. .

  Therefore, the short-circuit conductor 120 can be safely mounted by mounting the short-circuit conductor 120 between both ends of the low conductive member 104 at that timing.

  FIG. 10 shows a state where the short-circuit conductor 120 is mounted.

  As described above, when the voltage between the both ends of the low conductive member 104 becomes equal, the short-circuit conductor 120 is attached between both ends of the low-conductive member 104, so that the batteries B 1 and B 2 are connected via the short-circuit conductor 104. The DC / DC converter 200 can be fully connected. That is, the current hardly flows through the low-conductive member 104 having a high resistance value, and flows between the first terminal 101 and the second terminal 102 via the short-circuit conductor 120, and the original connection state is obtained. Thereby, the DC / DC converter 200 exhibits the original voltage conversion function, and converts the high voltage on the high voltage power supply line 205 side to the low voltage on the low voltage power supply line 206 side.

  Next, the case of removing the connection will be described.

  For example, when the connection is removed for maintenance or long-term operation stop, first, the service plug 10B, that is, the short-circuit conductor 120 is removed from between both ends of the low conductive member 104.

  FIG. 11 shows a state in which the short-circuit conductor 120 is removed from both ends of the low conductive member 104.

  At the stage of removing the short-circuit conductor 120 (service plug 10B), since a state in which a current flows through the low conductive member 104 instead of the short-circuit conductor 120 is secured, there is no possibility that an arc is generated when the short-circuit conductor 120 is removed. .

  When the short-circuit conductor 120 is removed, the control circuit 106 detects the removal of the short-circuit conductor 120, turns off the first switch SW1, and interrupts conduction between the first terminal 101 and the second terminal 102. When the first switch SW1 is turned off, only a small current flows through the low conductive member 104, so that no arc is generated at the switch contact.

  Here, once the first switch SW1 is turned off, the first connection SW1 is not turned on again unless the first connection is started. Therefore, it is safe even if the short-circuit conductor 120 is erroneously attached again.

  In this state, since the batteries B1 and B2 and the DC / DC converter 200 are securely cut off, the batteries B1 and B2 can be safely removed from the first terminal 101 side without fear of arcing.

  When removing the connection on the DC / DC converter 200 side, the connection on the battery B1, B2 side is not yet removed at this point. The reason is that if the connection on the battery B1, B2 side is removed, the control circuit 106 is turned OFF, and the subsequent safety control at the time of removing the connection on the DC / DC converter 200 side cannot be performed.

  After the short-circuit conductor 120 is removed and the first switch SW1 is turned off, the second switch SW2 is turned on by a command from the control circuit 106, whereby the ground line 107 is opened.

  Accordingly, the electricity accumulated in the capacitors 241 and 242 inside the DC / DC converter 200 is discharged to the ground (for example, the vehicle body) through the arc prevention resistor 108 dedicated to the capacitors 241 and 242. Also in this case, since the resistance value of the arc prevention resistor 108 is set to a value of several kΩ to several tens kΩ, the above discharge is caused by the capacitors 241 and 242 in the DC / DC converter 200 to the ground. It is carried out with a very small current of several mA to several tens mA. Therefore, no arc is generated.

  Thereafter, the control circuit 106 monitors the state in which electricity is discharged from the capacitors 241 and 242 inside the DC / DC converter 200 to the ground by detecting the voltage value on the second terminal 102 side, and the voltage value becomes low (that is, When it is detected that the electricity that can be discharged has decreased, the control circuit 106 turns off the second switch SW2 and cuts off the ground line 107.

  FIG. 12 shows this state. At this stage, the control circuit 106 is ON, and the first switch SW1 and the second switch SW2 are OFF.

  In this state, an LED or the like is lit to inform the worker that it is safe. In this state, it is possible to safely remove the power line and perform maintenance work. Then, by removing the terminal of the power supply line from the batteries B1 and B2 connected to the fixing box 10B, the control circuit 106 is turned off without power supply.

  As described above, according to the safety system described above, it is possible to avoid the occurrence of arcs that occur when a power line is attached or removed, by simply performing a simple operation of plugging / unplugging the service plug, and work safely. be able to. In particular, when the power supply component is being maintained, by removing the service plug before the work, the power supply from the battery can be cut off, so the work can be performed safely on the high voltage side. Further, when the automobile is not used for a long period of time, it is possible to easily prevent the batteries B1 and B2 from rising simply by removing the service plug 10B. In addition, since the control circuit 106 provided in the safety device 100 exhibits a predetermined function, it is possible to proceed safely with a simple procedure.

  FIG. 13 is a diagram illustrating an example of the insertion position of the safety device 100.

  8 to 12, the position indicated by P <b> 1 in FIG. 13, that is, the case where the safety device 100 is inserted and connected between the terminal box 500 and the DC / DC converter 200, is indicated by P <b> 2 in FIG. 13. The safety device 100 may be inserted and connected at a position, that is, between the batteries B1 and B2 and the terminal box 500, or the safety device 100 may be inserted and connected at both positions.

It is a block diagram of the connection box with a safety device of embodiment of this invention, and is a perspective view which shows the state of the connection box before connecting. It is sectional drawing of the said connection box of the state of FIG. It is a perspective view which shows the state of the said connection box which attached the terminal. It is sectional drawing of the said connection box of the state of FIG. It is a perspective view which shows the state of the said connection box at the time of completion | finish of a connection. It is sectional drawing of the said connection box of the state of FIG. It is a block diagram of the safety device for power supply circuits of embodiment of this invention. It is a block diagram of the safety system of the power supply circuit of embodiment of this invention, and is a figure which shows the state before a connection. It is a block diagram which shows the state before mounting | wearing of a short circuit conductor (service plug) after the connection of the said safety system. It is a block diagram which shows the state after mounting | wearing with a short circuit conductor (service plug) after the connection of the said safety system. It is a block diagram which shows a state when a short circuit conductor (service plug) is removed from the state after the connection of the safety system. It is a block diagram which shows the state which can remove a connection safely in the said safety system. It is explanatory drawing for demonstrating the location which can insert a safety device in the said safety system. It is a block diagram of the conventional power supply circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Connection box 11 Insulation box 12 Insulation cover 13 Low electroconductive member 14 Short-circuit conductor 14a Surface contact part 14b Engagement protrusion 15A, 15B Terminal accommodating part 19a Engagement groove 20A, 20B, 205, 206 Power supply line 21A, 21B Terminal 25 Engagement Joint hole 22 Flat plate portion 100 Safety device 101 First terminal (first connection portion)
102 2nd terminal (2nd connection part)
DESCRIPTION OF SYMBOLS 103 Conduction path 104 Low electroconductive member 106 Control means 120 Short-circuit conductor 108 Arc-preventing resistance 107 Ground line 200 DC / DC converter 201,202,207 Connection part 210 Primary side positive terminal of DC / DC converter 220 DC / DC converter Secondary side positive terminal B, B1, B2 Battery SW1 First switch SW2 Second switch

Claims (8)

It is a connection box with safety function that is inserted into the connection part of the power line,
An insulating box having a pair of terminal accommodating portions that can be spaced apart from each other to accommodate terminals; and
A low conductive member that is disposed between the pair of terminal accommodating portions in the insulating box, and in which terminals are contacted and conducted at both ends when the terminals are accommodated in the terminal accommodating portions;
A short-circuit conductor that is detachably mounted between the terminals in order to short-circuit between a pair of terminals that are in contact and conduction with both ends of the low-conductivity member,
An insulating cover that is detachably attached to the insulating box so as to hold the short-circuit conductor and close the opening of the insulating box;
A connection box with a safety function characterized by comprising A connection box with a safety function according to claim 1,
The short-circuit conductor is provided with an engagement protrusion to be inserted into an engagement hole formed in each terminal, and a surface contact portion in contact with a flat plate portion of each terminal, and the insulation box is engaged with the terminal. A connection box with a safety function, wherein an engagement groove for fitting a tip of the engagement protrusion penetrating the hole is provided. A safety device for a power supply circuit inserted and connected between connection parts of a power supply line connected to a positive terminal of a battery,
A first connection portion connected to a connection portion on the positive terminal side of the battery;
A second connecting portion connected to the opposite wiring portion;
A high-resistance low-conductive member inserted on a conduction path connecting the first connection portion and the second connection portion;
A normally-open first switch that is inserted closer to the first connection portion than the low conductive member on the conduction path and opens and closes the conduction path;
Control means having a function of controlling opening and closing of the first switch;
A short-circuit conductor that is detachably mounted to short-circuit both ends of the low-conductivity member, and
The control means is
When the power is supplied from the battery through the first connection portion and the ON state is established, the first switch is closed to ensure conduction of a conduction path connecting the first connection portion and the second connection portion. Function to
A function of opening the first switch when the short-circuit conductor is removed from a state where the short-circuit conductor is mounted to short-circuit both ends of the low-conductive member;
A safety device for a power supply circuit, comprising: A safety device for a power supply circuit according to claim 3,
The control means detects a voltage between both ends of the low-conductive member after opening the first switch, and when the voltage between both ends becomes a predetermined value or less, a signal for permitting the mounting of the short-circuit conductor A safety device for a power supply circuit having a function of outputting A safety device for a power supply circuit according to claim 3 or 4,
A ground line to be grounded is connected to the second connection part via an arc prevention resistor, and a normally open type second switch for opening and closing the ground line is inserted into the ground line,
The control means has a function of closing the second switch after opening the first switch in accordance with the removal of the short-circuit conductor that has short-circuited both ends of the low-conductive member. A safety device for a power circuit. A safety device for a power supply circuit according to claim 5,
The control means detects the voltage on the second connection portion side, and when the voltage on the second connection portion side becomes a predetermined value or less, outputs a signal notifying the end of discharge through the second connection portion, A safety device for a power supply circuit having a function of opening the second switch. A safety device for a power supply circuit according to claim 5 or 6,
A safety device for a power supply circuit, wherein the power supply line connected to the positive terminal of the battery is a power supply line connecting the positive terminal of the battery and a DC / DC converter. A high voltage battery for powering the high voltage load;
A low voltage battery for powering the low voltage load;
A high voltage power line connected to the positive terminal of the high voltage battery;
A low voltage power line connected to the positive terminal of the low voltage battery;
A DC / DC converter connected between the high-voltage power line and the low-voltage power line and converting a high voltage on the high-voltage power line side to a low voltage on the low-voltage power line side;
Between the connecting portion of the high voltage power supply line connecting the plus terminal of the high voltage battery and the primary plus terminal of the DC / DC converter, and the secondary plus terminal of the DC / DC converter and the plus terminal of the low voltage battery. 7. A safety system for a power supply circuit, wherein the safety device according to claim 5 or 6 is inserted and connected between at least one of the connecting portions of the low-voltage power supply lines to be connected.

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