JPH0677424U - Junction box device with lamp failure box - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a junction box device with a lamp failure box, and an object of the present invention is to simplify the circuit configuration, facilitate the production and assembly, and perform the maintenance and management quickly and reliably. . [Structure] A structure in which a junction box body 1 is provided with a lamp circuit 5 in which a variable resistance element is interposed in series between bus bars 13 and 14 of a connector portion 7 and connected to loads of lamps such as tail lamps 2a and 2b. Detects the terminal voltage of the variable resistance element due to the abnormal current of the tail lamp.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a junction box device with a lamp failure box installed in a vehicle body of an automobile. It is installed to form a wiring concentrated portion between wire harnesses.

[0002]

[Prior art]

 Conventionally, for example, a junction box device with a lamp failure box equipped with a lamp failure (lamp disconnection detection device) for detecting disconnection of the tail lamp itself or disconnection of a wire harness for the tail lamp is shown in FIG. There is one shown in 6. That is, a lamp circuit 53 formed by a first connector 51 connected to tail lamps 50a and 50b mounted on the rear part of the vehicle body and a blade type fuse 52 connected in series to the connector 51, for example. A junction box main body 56 having a connector portion 55 having terminal portions 54a and 54b connected to the fuse 52 and the connector 51, a second connector 57 connected to an indicator lamp (not shown), And a voltage comparator 61 of a current detection circuit 60 connected in parallel to the terminal portions 59a and 59b on both sides of the detection resistor 58 which is connected to the lamp circuit 53 in series via the connector portion 55 and detachably. And a lamp failure box 62.

When a lamp switch (not shown) is turned on, the voltage of the current detection circuit 60 in the lamp failure box 62 detachably attached to the junction box body 56 via the fuse 52 and the connector portion 55. A current I flows through the comparator 61 to the lamp circuit 53 through the detection resistor 58 and the connector 55, and the tail lamps 50a and 50b are turned on.

If at least one of the plurality of tail lamps 50a and 50b has its own tail lamp 50a, 50b itself disconnected, or if the wiring of the associated wire harness or the like is disconnected, the current I flowing through the lamp circuit 53 decreases. Therefore, the voltages of the terminal portions 59a and 59b at both ends of the detection resistor 58 change. This voltage change is detected by the voltage comparator 61 of the current detection circuit 60 connected in parallel to the terminals 59a and 59b on both sides of the detection resistor 58, and the external indicator lamp (not shown) is turned on. The driver detects that the tail lamps 50a, 50b themselves are disconnected or that the wiring of a wire harness or the like related thereto is disconnected. Moreover, even when an excessive current I flows to the lamp circuit 53 due to a short circuit in the wire harness, the current comparison of the current detection circuit 60 connected in parallel to the terminal portions 59a and 59b at both ends of the detection resistor 58. The device 61 detects a change in voltage and lights an indicator lamp (not shown) to detect a short circuit in the wire harness.

[0005]

[Problems to be solved by the device]

 However, in the circuit configuration of the conventional junction box device with a lamp failure box shown in FIGS. 5 and 6, the fuse 52 of the lamp circuit 53 and the detection resistor 58 of the current detection circuit 60 are separately provided in the junction box body 56. Since it is provided on the lamp failure box 62, the circuit configuration becomes complicated, the number of parts increases, and it takes time to manufacture and assemble, and maintenance and management also take time. Therefore, an object of the present invention is to simplify the circuit configuration, facilitate the production and assembly, and perform the maintenance and management quickly and surely.

[0006]

[Means for Solving the Problems]

 The present invention has been made in view of the above problems, and a lamp box circuit in which a variable resistance element is connected in series to a load of a lamp such as a tail lamp is provided in a junction box body to form a junction box device with a lamp failure box. An element was inserted in series between the busbars of the connector section for the lamp failure box to detect the terminal voltage of the variable resistance element.

[0007]

[Action]

 Since a variable resistance element was inserted in series between the busbars in the main body of the junction box, abnormal current flows due to short-circuiting of the wire harness, etc., and the temperature rises rapidly. The resistance value, which was several tens of mΩ, suddenly increases, but the change in the voltage between the terminals of this variable resistance element is detected. Therefore, the variable resistance element becomes a resistance against the current and becomes a substitute part for the fuse. Moreover, since the variable resistance element normally has a resistance value of several tens of mΩ, it also serves as a detection resistance, and one of the plurality of tail lamps has a core disconnection or a wire related thereto. When the harness is broken and a small amount of current flows in the lamp circuit, the voltage change due to the change in the amount of current is detected by the voltage across the terminals of the variable resistance element.

[0008]

【Example】

 1 to 3, reference numeral 1 denotes a junction box body, and the junction box body 1 has connectors provided on the upper surface for a plurality of external tail lamps 2a and 2b (for example, two) mounted on the rear portion of the vehicle body. When the wire harness related to at least one of the tail lamps 2a and 2b is short-circuited and abnormal current flows and the temperature rises sharply above a certain temperature, the resistance value increases sharply. A variable resistance element, for example, a lamp circuit 5 for connecting the PTC element 4 in series, and a connector section 7 having detection terminals 6a and 6b connected to both ends of the PTC element 4 are provided on the lower side surface, for example.

Reference numeral 8 denotes a lamp failure box that is detachably attached to the lower surface of the junction box body 1 via the connector portion 7. The lamp failure box 8 has an external indicator lamp (not shown). Connector 9 provided on one side so as to be connected to a terminal 9 and terminals 11a and 11b of a current detection circuit 10 which can be connected in parallel to the lamp circuit 5 provided on the junction box body 1 via the connector portion 7. The current comparator 12 is provided.

As shown in the characteristic diagram of FIG. 4 showing the relationship between temperature and resistance, the PTC element 4 is operated when an abnormal current flows into the lamp circuit 5 due to a short circuit of wiring such as a wire harness. , The temperature rises rapidly and the resistance value increases more than the normal resistance value of several tens of mΩ, and at least one of the tail lamps among the plurality of tail lamps has a core disconnection or a wire related thereto. This is a standard for determining whether or not the amount of current flowing through the lamp circuit 5 is smaller than the set value of the detection resistor due to a broken wire in the harness. The PTC element 4 forms the current detection circuit 10 by being sandwiched in series between the front and rear bus bars 13 and 14 having the detection terminals 13 a and 14 a of the connector portion 7 protruding downward. It is supposed to do.

When a lamp switch (not shown) having the above-mentioned configuration is turned on, the PTC element 4 as a variable resistance element, which is connected in series to the tail lamps 2 a and 2 b and normally has a resistance value of several tens mΩ, A lamp failure box mounted on the lower surface of the junction box body 1 via bus bars 13 and 14 of a connector section 7 having detection terminals 13a and 13b to which terminal sections 6a and 6b on both sides of the PTC element 4 are connected. The current I flows to the voltage comparator 12 of the current detection circuit 10 in the lamp 8, and the tail lamps 2a and 2b are turned on.

When an abnormal current flows into the PTC element 4 due to a short circuit of the wire harness of the plurality of tail lamps 2a and 2b and the temperature rises sharply, the resistance of the PTC element 4 which is usually several tens mΩ. Since the value sharply rises as shown in the characteristic diagram showing the relationship between temperature and resistance shown in Fig. 4, the amount of current flowing through the PTC element 4 decreases, and the PTC element 4 serves as a fuse and both ends thereof. A voltage change occurs at the terminal portions 6a and 6b of the.

This voltage change is detected by the voltage comparator 12 of the current detection circuit 10 connected in parallel to the terminal portions 6a and 6b on both sides of the PTC element 4 via the detection terminals 13a and 14a of the connector portion 7, By turning on an indicator lamp (not shown), the driver can detect that there is a short circuit in the wiring of the wire harness or the like associated with the tail lamps 2a and 2b.

In addition, at least one of the plurality of tail lamps 2a and 2b has its own core lamp 2a, 2b itself disconnected, or a wire harness related thereto has a disconnection, so that a small amount of current is supplied to the lamp circuit 5. When a current I flows, at least one of the tail lamps 2a, 2b itself is disconnected by detecting the terminal voltage associated with the current change by the PTC element 4 having a detection resistance of several tens of mΩ. Or detect that the wire harness is broken.

Further, since the PTC element 4 is sandwiched between the bus bars 13 and 14 of the connector portion 7 having the detection terminals 13 a and 14 a connected to the lamp failure box 8, the structure is simple. It is convenient for Moreover, since the PTC element 4 is a single component, it has both a function as a fuse and a function as a detection resistor. Therefore, the number of parts is reduced, and maintenance and management such as replacement of parts at the time of failure are easy.

In the above embodiment, the tail lamps 2a, 2b are used as a load to short-circuit the related wire harnesses, the table lamps 2a, 2b themselves are broken, or the wire harness is broken. However, there are lamps such as clear lamps and hog lamps as well as tail lamps 2a and 2b as loads, and even when these lamps are disconnected, the wire harness is disconnected, or short-circuited. The present invention is applicable.

[0017]

[Effect of device]

 Since the variable resistance element of the lamp circuit is inserted between the bus bars of the connector and connected in series as described above, the variable resistance element functions as a conventional fuse and detection resistance, and the number of parts is small. This simplifies the circuit configuration, facilitates production and assembly, and facilitates replacement of parts in the event of a failure, ensuring reliable maintenance and management.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention.

FIG. 2 is a circuit configuration diagram of the same.

FIG. 3 is a perspective view of the main part of the same.

FIG. 4 is a characteristic diagram showing a relationship between temperature and resistance of a PTC element which is also a variable resistance element.

FIG. 5 is an exploded perspective view showing a conventional lamp failure box.

FIG. 6 is a circuit diagram of the same main part.

[Explanation of symbols]

 1 Junction box main body 2a, 2b Tail lamp 4 PTC element 5 Lamp circuit 7 Connector section 12 Voltage comparator

Claims (1)

[Scope of utility model registration request] 1. A junction box device with a lamp failure box in which a lamp circuit in which a variable resistance element is connected in series to a load of a lamp such as a tail lamp is provided in a junction box body is used, and the variable resistance element is a lamp failure. A junction box device with a lamp failure box, characterized in that the voltage between terminals of the variable resistance element is detected by being interposed in series between bus bars of a connector section for the box.