JP3092472B2 - Power supply device for automotive wiring harness - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device for an automobile wire harness, and more particularly, to an automobile wire harness in which a plurality of lines are bundled to connect a power source (battery) and various electric components. The present invention relates to a device for supplying electric power from a power supply to electric components mounted on an automobile, and more particularly to a device for preventing generation of heat and smoke when a short circuit occurs in the power supply device.

[0002]

2. Description of the Related Art Conventionally, in a wire harness for a vehicle, a power supply device for supplying power from a power source to various electric components such as a horn, a washer motor, and a parking brake switch mounted on the vehicle is shown in FIG. Configuration.

In FIG. 6, reference numeral 1 denotes a power supply (battery).
The positive terminal 1 a of the power supply 1 is connected to the positive terminal 3 a of the electrical component 3 via the positive line 2. A fuse 4 that is blown when a required amount of current flows is provided in the positive line 2. Some of the positive side lines 2 have an ignition switch 6 interposed therebetween. The negative terminal 3b of the electrical component 3 is a negative line 7
Is connected to the body 8 of the automobile. On the other hand, the negative terminal 1 b of the power supply 1 is connected to the body 8 via the ground line 9.

In this power supply device, when the ignition switch 6 is closed, the power is supplied from the plus terminal 1a of the power supply 1 to the power supply via the plus side line 2, the electrical component 3, the minus side line 7, the body 8 and the earth side line 9. A closed circuit that returns to the minus terminal 9 of 1 is formed, and power is supplied from the power supply 1 to the electrical component 3 by this closed circuit.

[0005] The body 8 has a large area and has burrs.
Since there is a sharp portion such as an edge, the plus side line 2 and the body 8 may interfere with each other and come into contact with each other as shown by a dotted line 2 'in FIG. At this time, the plus side terminal 1a and the minus side terminal 1b of the power supply 1 are connected by a closed circuit as indicated by a dashed line S1, and the power supply 1 is connected without the electric component 3.
Is connected to the plus side terminal 1a and the minus side terminal 1b. When this short-circuit occurs, an excessive current flows through the fuse 4, and the heat generated at the time of energization causes the fuse 4
Is melted, the closed circuit indicated by the dashed-dotted line S1 is opened, and heat generation and smoke generation at the contact portion C between the plus side line 2 and the body 8 are prevented.

[0006]

However, in the case of an intermittent short circuit (rare short) that occurs when the positive terminal 1a of the power supply 1 intermittently contacts the body 8, the fuse 4 is surely blown. Not necessarily. For example, when the blown portion of the fuse 4 blows at about 1000 ° C., the heat generated at the blown portion is 800 ° C. due to the rare short circuit.
If the fuse 4 is saturated to the extent, the fuse 4 will not be blown, and the contact portion C between the positive line 2 and the body 8 may generate heat or smoke, or the resin portion of the fuse 4 may be melted.

As described above, in the conventional power supply device, the body 8 of the vehicle having a large area and many sharp portions such as burrs and edges is connected to the minus terminal 3b of the electrical component 3 and the minus terminal 1b of the power supply 2. Since it is used for connection, there was a possibility that heat and smoke would be generated during a short circuit. The present invention has been made in order to solve the problem in the conventional power supply device for a wire harness for an automobile and to reliably prevent heat generation and smoke generation at a contact portion between a body and a line when a short circuit occurs. is there.

[0008]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a first method.
A power supply device for supplying power from a power supply to a general electrical component such as a horn mounted on a vehicle body with an insulating portion interposed therebetween so as not to be directly electrically connected to the body. First the positive terminal side of the electrical components
Ground line, the negative terminal side of the electrical component is directly connected to the body of the vehicle, and the negative terminal side of the power supply and the body of the vehicle are connected via a second fuse. And the second
The capacity of the fuse is set to be smaller than the capacity of the first fuse.

A second aspect of the present invention is a power supply apparatus for supplying power from a power supply to general electrical components such as a horn mounted on a vehicle body with an insulating portion interposed therebetween so as not to be directly electrically connected to the body. Connecting a positive line having an ignition switch and a first fuse on the positive terminal side of the power supply to the positive terminal side of the general electrical component;
Branched into a positive line and a second positive line connected to the positive terminal side of the equipment grounding electrical component, and connected the negative terminal side of the general electrical component to the negative terminal side of the power supply with a negative line, Connecting the negative terminal side of the equipment ground type electrical component directly to the body of the vehicle, and connecting the negative terminal side of the power supply to the body of the vehicle with a ground line having a second fuse interposed therebetween; A power supply device for an automotive wire harness, wherein the capacity of the first fuse is smaller than the capacity of the first fuse.

[0010]

[0011]

In the first power supply device, since the minus terminal of the power supply is connected to the body by the ground line having a small-capacity fuse, the short circuit occurs because the plus line interferes with and contacts the body. Then, a closed circuit returning from the positive terminal of the power supply to the negative terminal of the power supply via the positive line, the body and the ground line is closed, and the small-capacity fuse interposed in the ground line is instantaneously blown.

In the second power supply device, the negative terminal of the first electrical component is directly connected to the negative terminal of the power supply via the negative line without interposing a body, and the negative terminal of the power supply is connected to the negative terminal of the power supply. Are connected to the body by an earth line with a small capacity fuse. Therefore, the first plus side line interferes with the body,
When a short circuit occurs due to contact, a closed circuit is returned from the positive terminal of the power supply to the negative terminal of the power supply via the positive line, the body and the ground line, and the second positive line interferes with the body. If a short circuit occurs due to contact, a closed circuit that returns from the positive terminal of the power supply to the negative terminal of the power supply through the positive line, the body, and the ground line is closed. Fuse of capacity surely blows instantaneously.

[0014]

Next, the present invention will be described in detail with reference to the embodiments shown in the drawings. The power supply device for a wire harness for a vehicle according to the reference embodiment of the present invention shown in FIG. 1 is provided with an electric device mounted on a vehicle body via an insulating portion so as not to be directly electrically connected to the body 8 of the vehicle. A power is supplied from a power supply 1 to a product 10 (hereinafter, referred to as “general electrical component”).

The plus terminal 1a of the power supply 1 and the general electrical equipment 10
Are connected by a plus side line 12. The ignition switch 6 and the first fuse 14 are provided on the positive line 12 in this order from the positive terminal 1a of the power supply 1. Further, the minus terminal 1 b of the power supply 1 and the minus terminal 10 b of the general electrical component 10 are connected by a minus line 15.

In this power supply device, when the ignition switch 6 is closed, the positive terminal 1a of the power supply 1 is connected to the negative line 12 of the power supply 1 via the positive line 12, the general electrical component 10, and the negative line 15. A return closed circuit S2 is formed, and power is supplied from the power supply 1 to the general electrical component 10 by the closed circuit S2.

As described above, in this power supply device, the negative terminal 10b of the general electrical component 10 is directly connected to the negative terminal 1b of the power supply 1 by the negative line 15, and the body 8 is interposed therebetween. Therefore, even if the plus side line 12 interferes with and contacts the body 8 as shown by a dotted line 12 'in FIG. No heat or smoke is generated at the contact portion C of No. 8.

Next, a first embodiment of the present invention shown in FIG. 2 will be described. In this embodiment, the electric power is supplied from the power supply 1 to the general electric component 10 in the same manner as in the above-described reference embodiment, and the negative terminal 1b of the power supply 1 is connected to the body 8 through the ground line 17, and this ground Line 17
Is provided with a second fuse 18. The capacity of the second fuse 18 is set to a small capacity (about 10 A) which is less likely to generate heat and smoke at the contact portion C between the plus line 12 and the body 8 than the first fuse 14.
Other configurations of the present embodiment are the same as those of the reference embodiment, and the same components are denoted by the same reference numerals.

In this power supply device, when the ignition switch 6 is closed, the positive terminal 1a of the power supply 1 is connected to the negative line 12 of the power supply 1 through the positive line 12, the general electrical equipment 10, and the negative line 15. A return closed circuit is formed, and by this closed circuit, the general electrical component 10
Is supplied with power from the power supply 1.

As described above, in the power supply apparatus of the first embodiment, the negative terminal 10b of the general electrical component 10 is directly connected to the negative terminal 1b of the power supply 1 by the negative line 15. 8 is not interposed,
The negative terminal 1b of the power supply 1 is connected to the body 8 by an earth line 17 provided with a second fuse 18. Therefore, the plus side line 12 corresponds to the dotted line 1 in FIG.
When a short circuit occurs due to interference or contact with the body 8 as shown by 2 ', as shown by a dashed line S3, the positive terminal 1a of the power supply 1 is connected to the plus side line 12 and the body 8
And the negative terminal 1 of the power supply 1 via the ground line 17
The circuit returning to b is closed. Since the second fuse 18 interposed in the ground line 17 has a small capacity, when the short circuit occurs, the second fuse 18 is instantaneously blown, and the circuit indicated by the dashed-dotted line S3 is quickly opened to eliminate the short circuit. Therefore, in this power supply device, even when a short circuit occurs,
Heat is generated at the contact portion C between the positive side line 12 and the body 8,
Does not emit smoke. Further, even when the rare short occurs as described above, the second fuse 18 may be operated as described above.
Has a small capacity, so that it is surely melted and does not generate heat or smoke at the contact portion C.

Next, a second embodiment of the present invention shown in FIG. 3 will be described. The power supply device according to the second embodiment includes an electrical component 11 that is directly attached to a body 8 of a vehicle such as a horn, a washer motor, a parking brake switch, etc., and directly connects a minus terminal 11b to the body 8 without interposing an electric wire. (Hereinafter referred to as “Equipment grounding type electrical equipment”)
The power is supplied from the power supply 1 to the power supply.

FIG. 4 shows the above-mentioned equipment grounding type electrical component 11.
2 shows an attachment structure to the body 8. In FIG. 4, the equipment grounding type electrical component 11 is a horn. However, in the case of another device grounding type electrical component 11 such as a washer motor, it is mounted on the body 8 by the same mounting structure. The device ground type electrical component 11 includes a plate-shaped mounting portion 20 made of a conductor, and the mounting portion 20 is provided with a through hole 20a. On the other hand, the equipment ground type electrical component 11 of the body 8
Is provided with a screw hole 8a at the mounting position, and the equipment grounding type electrical component 11 is mounted on the body 8 by screwing the screw 21 inserted through the through hole 20a into the screw hole 8a. The mounting portion 20 is connected to the minus terminal 11b (shown only in FIG. 3) of the equipment grounding type electrical component 11, and the minus terminal 11b and the body 8 are electrically connected via the mounting portion 20. I have.

The plus terminal 1a of the power supply 1 and the plus terminal 11a of the equipment grounding type electrical component 11 are connected in the same manner as in the first embodiment.
The ignition switch 6 is connected to the ignition switch 6 by a positive line 12 having a first fuse 14 having a relatively large capacity. On the other hand, the minus terminal 1b of the power supply 1
It is connected to the body 8 by an earth line 17 provided with a second fuse 18 having a small capacity of about A. Therefore, in the second circuit, when the ignition switch 6 is closed, the plus terminal 1a of the power supply 1 is connected to the plus line 12, the equipment grounding type electrical component 11, the body 8,
A closed circuit that returns to the minus terminal 1b of the power supply 1 via the ground line 17 is formed, and power is supplied from the power supply 1 to the equipment ground type electrical component 11 by this closed circuit.

In FIG. 3, when the plus side line 12 interferes with and comes into contact with the body 8 as shown by a dotted line 12 'and a short circuit occurs, as shown by the dashed line S4, the positive terminal 1a of the power supply 1 The circuit returning to the minus terminal 1b of the power supply 1 through the plus line 12, the body 8 and the ground line 17 is closed. Since the second fuse 18 interposed in the ground line 17 has a small capacity, when the short-circuit occurs, the second fuse 18 is blown instantly, and the circuit indicated by the dashed-dotted line S4 is quickly opened to eliminate the short-circuit. Therefore,
In this power supply device, even when a short circuit occurs, heat generation and smoking do not occur at the contact portion C between the positive line 12 and the body 8. In addition, even when the rare short occurs, the second fuse 18 has a small capacity as described above, so that the second fuse 18 is reliably blown, and no heat or smoke is generated in the contact portion C.

The power supply device according to the third embodiment of the present invention shown in FIG. 5 has a structure in which the first embodiment and the second embodiment are combined. In this power supply device, the plus side line 12 provided with the ignition switch 6 and the first fuse 14 is connected to the first plus side line 12a connected to the plus terminal 10a of the general electrical component 10 at the branch point P1, and the equipment ground. It branches into a second plus side line 12b connected to the plus terminal 11a of the mold electrical component 11. Other structures of this embodiment are the same as those of the above-described embodiment.
The same elements are denoted by the same reference numerals.

When the first positive side line 12a interferes with and comes into contact with the body 8, the positive terminal 1a of the power supply 1 passes through the positive side line 12, the body 8 and the earth line 17 as in the first embodiment. The circuit returning to the negative terminal 1b of the power supply 1 is closed. Further, when the second plus side line 12b interferes with and contacts the body 8 to cause a short circuit, the power supply 1 is turned on in the same manner as in the second embodiment.
From the plus terminal 1a to the minus terminal 1b of the power supply 1 via the plus line 12, the body 8 and the ground line 17, is closed.

As described above, in the third embodiment, when either the first positive line 12a or the second positive line 12b is short-circuited, a closed circuit including the ground line 17 is formed. Since the second fuse 18 interposed between the first and second fuses 18 has a small capacity, the second fuse 18 is reliably and instantaneously blown, and the first positive line 12a and the second
Heat generation, smoke generation, and the like do not occur at the contact portion between the plus side line 12b and the body 8.

[0028]

As is apparent from the above description, in the first power supply device of the present invention, the negative terminal of the power supply is connected to the body by the earth line provided with a small capacity fuse. If the positive line interferes with and contacts the body, causing a short circuit, a closed circuit that returns from the positive terminal of the power supply to the negative terminal of the power supply through the positive line, the body, and the earth line is closed and intervenes in the earth line. The blown small-capacity fuse blows instantly without fail. Therefore, in the present power supply device, it is possible to prevent heat generation and smoke generation at the contact portion between the plus line and the body when a short circuit occurs. In particular, since the fuse interposed in the ground line as described above has a small capacity, it can be reliably blown even when a rare short circuit occurs, thereby preventing heat generation and smoking at the contact portion.

[0029]

In the second power supply device of the present invention, the negative terminal of the first electrical component is directly connected to the negative terminal of the power supply through the negative line without interposing the body, and the negative terminal of the power supply is connected. The terminals are connected to the body by an earth line with a small capacity fuse. Therefore, the first plus side line interferes with the body,
When a short circuit occurs due to contact, a closed circuit is returned from the positive terminal of the power supply to the negative terminal of the power supply via the positive line, the body and the ground line, and the second positive line interferes with the body. When a short circuit occurs due to contact, a closed circuit that returns from the positive terminal of the power supply to the negative terminal of the power supply through the positive line, the body, and the ground line is closed. Fuse of capacity surely blows instantaneously. Therefore, in this power supply device, it is possible to prevent heat generation and smoking at a contact portion between the plus line and the body when a short circuit occurs. In particular, since the fuse interposed in the ground line as described above has a small capacity, it can be reliably blown even when a rare short circuit occurs, thereby preventing heat generation and smoking at the contact portion.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a power supply device for an automobile wire harness according to a reference example of the present invention.

FIG. 2 is a circuit diagram showing a power supply device for an automobile wire harness according to a first embodiment of the present invention.

FIG. 3 is a circuit diagram illustrating a power supply device for an automobile wire harness according to a second embodiment of the present invention.

FIG. 4 is an exploded perspective view showing a structure for attaching a horn to a body.

FIG. 5 is a circuit diagram showing a power supply device for an automobile wire harness according to a third embodiment of the present invention.

FIG. 6 is a circuit diagram showing a conventional power supply device for an automobile wire harness.

Claims (2)

(57) [Claims] (1)No direct electrical connection to the body
Such as a horn attached to the vehicle body with an insulating part
To a power supply device that supplies power from a power supply to general electrical components
And  With the positive terminal of the power supplyGeneral aboveConnect the positive terminal side of
Connect the positive side line with the first fuse
GeneralConnect the negative terminal of the electrical component to the car body
Connect and connect the negative terminal of the power supply to the car body
-Connected with a ground line via a second fuse,
The capacity of the second fuse is larger than the capacity of the first fuse.
Set to small capacityAutomotive wire characterized by the following:
Harness power supply. (2)No direct electrical connection to the body
Such as a horn attached to the vehicle body with an insulating part
To a power supply device that supplies power from a power supply to general electrical components
And Connect the ignition switch and the first
Connect the plus side line with a fuse
The first positive line connected to the positive terminal side of the
The second positive side connected to the positive terminal side of the ground type electrical component
Branch into the line and Connect the negative terminal of the above general electrical equipment to the negative terminal of the power supply.
Side with a negative line, and
The negative terminal side of the electrical component is directly connected to the car body.
Connect the negative terminal of the power supply to the car
Dee connected with earth line with second fuse
Then, the capacity of the second fuse is changed to the capacity of the first fuse.
Smaller capacity than Automotive wiping characterized by the following:
Yaharness power supply.