JPS6246385B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the wiring of a wire harness for a vehicle, and more particularly to a wiring harness wiring method for preventing the generation of radio noise in a vehicle having a rear differential camera and a radio antenna.

Since vehicles generally have many sources of radio noise, various measures have been taken, such as incorporating noise prevention devices into each device that is a source of noise.

Particularly in these days when car radios have become essential accessories for vehicles, if the radio's performance is hampered by these noises, it will affect the commercial value of the vehicle itself, so it has been a long time since we've worked hard to suppress radio noise. Various studies have been conducted for this purpose.

First, a conventional wire harness wiring method will be described.

FIG. 1 shows a layout diagram of the rear trunk area of a vehicle. A trunk room main harness 2 is arranged on the body panel side of the trunk room 1, and rear combination lamp harnesses 3R, 3L, a stop tail sensor harness 4, and a license lamp harness 5 are branched from the trunk room main harness 2, respectively.

And rear combination lamp 6R, 6
The license lamp 7 is grounded to the body panel 8 by a body ground harness 7a.

Figure 2 shows the rear combination lamp 6R,
This shows the wiring diagram for 6L, where 8' is the ground line for rear combination lamps 6R and 6L.
A ground line using a body panel is shown.

Note that B is an on-vehicle battery, and 9 is a switch circuit including an ignition switch, a turn signal switch, a hazard switch, an ignition relay, and a flasher unit. Also, 19
R and 19L are side combination lamps.

FIG. 3 shows a layout diagram of a rear parcel in front of the trunk of a vehicle having a whip antenna in the rear fender.

In this part, the body harness 11, which is the main harness from the body, is located below the rear parcel. The body harness 11 includes a speaker harness 12 connected to rear speakers 10R and 10L below the rear parcel, harnesses 45R and 45L connected to the rear differential gear, and a trunk room lamp 1.
A wire harness 15 and a trunk room lamp switch harness 16 connected to the trunk lamp switch 4 are branched.

Furthermore, a tank unit gauge harness 17 is branched from the trunk main harness 2 at the trunk room side portion. Power antenna motor harness 1 from speaker harness 12
8 are branched.

FIG. 4 shows a wiring diagram of the right side of the dash. Here, the instrument harness 2
1, room lamp harness 22, fuse box 23, time control unit 2
4. There are an automatic door lock timer unit 25 and a power window timer unit 26.

On the right side of the dashboard, the main harness 20 branches into an instrument harness 21, a room lamp harness 22, various harnesses connected to each unit, and an air conditioner/audio harness 27, which are connected to electrical equipment installed at the rear of the vehicle. This is body harness 11.

FIG. 5 shows an example of a body harness wired on the side of the body. As shown in the figure, all the body harnesses 11 are bundled and wired on the body panel 8.

In this body side part, body harness 11
A handbrake harness 30 and a seatbelt harness 31 are branched from there. Here, 32 is a handbrake, 33 is a console box, and 34 is a
indicates a door.

Figures 6 and 7 show an example of conventional wiring harness wiring for a vehicle that has a rear differential and a radio antenna on the rear window.
FIG. 6 shows the wiring as viewed from the seat side toward the rear window of the vehicle, and FIG. 7 shows the wiring as viewed from above the rear parcel tray panel toward the rear of the vehicle.

Hereinafter, in explaining the wiring configuration of this wire harness, the wiring will be divided into two types and explained.

In other words, the thick solid lines indicate the wiring connected to the radio antenna and the rear differential camera-related equipment, and the thick broken lines indicate the radio and rear differential camera-related wiring arranged on the back side of the shield when viewed from the viewpoint. shall be. In addition, two parallel solid lines indicate wiring connected to lights, lamps, speakers, motors, air purifiers, etc., and two parallel dashed lines indicate wiring connected to the back side of the shield as seen from the viewpoint. This figure shows the wiring of these lights, etc.

In FIG. 6, 41 is a radio antenna, and 42 is a rear differential camera. These multi-wire radio antenna 41 and rear differential gear 42
are printed with conductors on the vehicle interior side of the rear glass 43 on the rear surface of the vehicle, and are connected to defogger power supply terminals 44R and 44L provided on both sides of the rear glass 43, respectively.

The reason why the radio antenna 41 is electrically integrated with the rear defogger 42 in this way is to improve the sensitivity of the radio antenna 41 in the AM band by also using the rear defogger 42 as an antenna.

Note that in FIG. 6, AT is an antenna output terminal, which is connected to an in-vehicle radio via a shielded wire (not shown).

Here, the wire harness 45R connected to the defogger power supply terminal 44R is guided to the right (left side of the vehicle) along the upper surface of the rear parcel tray panel (hereinafter simply referred to as "tray panel") 46, and is connected to the defogger power supply terminal 44L. An inductor filter 4 for reducing high frequency noise is provided at the bottom of the tray panel 46 along with the connected wire harness 45L.
Guided by 7. From here, the two wire harnesses 45R and 45L are combined to form a wire harness 45, which is wired along the lower rear portion of the tray panel 46 toward the right side of the vehicle together with other wire harnesses.

48 is a defogger sensor attached below the rear defogger 42. The rear defogger 42 is turned on and off based on the sensor signal detected by the defogger sensor 48. Wire harness 49 connected to both terminals of rear differential sensor 48
R and 49L each pass through the tray panel 46 and then form a wire harness 50 together with the wire harness 45 described above on the lower surface side thereof.

In the following explanation, these defogger-related wire harnesses 45R, 45L, 45, 49R,
49L and 50 are collectively referred to as a defogger wire harness.

Further, in FIGS. 6 and 7, 10R and 10L are both rear speakers, 14 is a trunk room lamp, and 51 is an air cleaner. 6R and 6L are rear combination lamps installed on the left and right sides of the rear end of the vehicle, respectively.

Wire harnesses 12R and 12L connected to rear speakers 10R and 10L, and wire harnesses 15 and 5 connected to trunk room lamp 14 and air cleaner 51, respectively.
2 are bundled at the rear of the lower surface of the tray panel 46,
The wire harness 53 is sequentially bundled together with the wire harness 50 described above.

Here, in FIGS. 6 and 7, the hatched portion of the line representing the parallel wire harnesses shows the state of the combined wire harness wiring.

Next, wire harnesses 3R and 3L connected to rear combination lamps 6R and 6L
The two wires are guided as one toward the rear right side wall of the vehicle toward the tray panel 46, and then
It is combined with the wire harness 53 on the lower surface to form a rear main harness 54, and is wired so that the upper surface of the rear seat back body panel 8a faces toward the front of the vehicle, forming the body harness 11 shown in FIG.

Note that, among the wire harnesses forming the rear main harness 54, the defogger sensor 4
Wire harnesses 49R and 49 connected to 8
In L, a defogger sensor amplifier 55 is interposed in the middle of the wiring of the rear main harness 54.

In addition, in the following explanation, the wire harnesses 3R, 3L, 12R, 12 connected to electrical components are
When L, 15, and 52 are collectively referred to as an electrical wiring harness.

As described above, according to the conventional main harness wiring method, the rear combination lamp 6R,
The ground side terminals such as 6L are grounded to the body panel, and the rear combination lamps 6R, 6L, etc. Panel 8 was used as ground.

For this reason, the earth line, which is supposed to be lossless, naturally has a loss in the body panel section, which is a little over 2 meters long in a straight line, resulting in a voltage drop.

Therefore, most of the contact opening/closing noise, slider noise, etc. that occur when turning on/off electrical components such as various lamps (for example, turn signals, cross clamps, etc.) are radiated from the body panel 8. This increases the probability that the signal will enter the antenna, causing radio interference.

Further, wire harnesses for electrical components such as various lamps and a defogger wire harness are combined at the rear parcel portion to form a body harness 11, which is wired on the body panel 8 and extends to the front of the vehicle.

Therefore, contact opening/closing noise and slider noise superimposed on the electrical component wire harness are guided to the defogger wire harness, radiate through the rear defogger 42 as an antenna, and mix into the radio antenna 41.
This caused a lot of noise on the radio.

In particular, radios in vehicles in which a rear differential and a radio antenna are integrated with the surface of the rear glass or are wired close to each other generate a large amount of noise.

In addition, in order to prevent the generation of such noise, it is necessary to take measures such as installing a noise preventer for each electrical component that is a noise source.

The object of the present invention is to eliminate the above-mentioned drawbacks of conventional wire harness wiring methods.

Therefore, when wiring a wiring harness for a vehicle that has at least a rear differential, various lamps, electrical components such as various motors, and a radio antenna, the present invention provides a method for wiring the wiring harness of a vehicle that has at least a rear differential gear, various lamps, electric components such as various motors, and a radio antenna, by connecting the ground of various lamps via lead wires without connecting them to the body panel. the battery to the negative terminal, and keep the defogger wire harness associated with the rear defogger and the electrical wiring harness connected to the electrical components separated from each other at least at the rear of the vehicle from the dash side to prevent noise radio waves from coming from the body panel and rear defogger. To provide a wiring harness wiring method that prevents noise from entering a car radio by preventing radiation from being irradiated.

Furthermore, in a second invention, when wiring a wire harness of a vehicle in which the radio antenna is disposed close to or integrated with the rear differential gear and is disposed on the rear glass, in addition to the above, To provide a wire harness wiring method in which a noise prevention filter element is interposed between the wire harness and a body panel, and even noise slightly induced in the defogger wire harness can be removed.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 8 shows an embodiment of the present invention.
It is a wiring diagram of rear combination lamps 6R, 6L, etc.

As shown in this figure, the ground side terminals of the rear combination lamps 6R, 6L are wired and connected by lead wires 60 without being grounded to the body panel up to the battery.

FIG. 9 shows an example of wiring in the rear parcel section in front of the trunk of a vehicle having a radio antenna in the rear fender section.

As shown in the figure, the harnesses 45R and 45L connected to the rear differential gear are not combined with the trunk room main harness 2, which is an electrical equipment harness, but are led to the body in a separated wiring state.

FIG. 10 shows an embodiment of the harness wiring method for the body part. As shown in the figure, a conventional body harness 11 (fifth
) is separated into the electrical equipment wire harness 11a connected to the above-mentioned electrical equipment and the defogger wire harness 11b related to the above-mentioned rear defogger 42,
Both harnesses 11a and 11b are wired so as to be separated by at least 5 cm.

In this way, the defogger wire harness 11b
By separating this from the electrical equipment wire harness 11a, it is possible to prevent contact opening/closing noise from being induced in the defogger wire harness 11b.

For example, if you bundle other harnesses into a harness that has contact switching noise, the induction will be around 60%, and the
It has been confirmed that it decreases to about 10% if the distance is ~10 cm.

FIG. 11 shows an embodiment in a rear parcel area in front of a trunk room of a vehicle having a rear differential camera and a radio antenna on the rear glass.

Here, there is no change from the conventional wiring method for each wire harness connected to the electrical components, that is, the trunk room lamp 14, the air cleaner 51, the rear speakers 10R and 10L, and the rear combination lamps 6R and 6L.

However, the wire harness 61 connected to the input terminal side of the inductor filter 47 for high frequency noise reduction is connected from the inductor filter 47 to the rear end of the vehicle of the rear parcel tray panel 46 like the conventional wire harness 45 shown in FIG. Along,
Wire harness 12L, 1 to connect to other electrical equipment
5, 52, 12R, etc., and connect the rear seat back body panel 8 from the terminal provided at the front end of the vehicle of the inductor filter 47.
Wires are routed toward the right side wall of the vehicle along line a, and are separated from wiring related to electrical components.

Also, wire harnesses 69R and 69 connected to the terminals of the defogger sensor 48 shown in FIG.
L is conventional wire harness 49R and 49L
Instead of forming the wire harness 53 together with the electrical wiring harness, wires are connected to the defogger sensor amplifier 55 by wiring each independently with the upper surface of the tray panel 46 facing the front of the vehicle, and the output wire 56 is connected to the wire harness. 61 to form the defogger wire harness 11b, and as mentioned above, the electrical equipment wire harness 11a as a body harness.
Wire the wires to the side of the needle while keeping the distance between the two.

Further, near the input side of the defogger sensor amplifier 55 or inside the unit of the defogger sensor amplifier 55, between the wire harnesses 69R and 69L and the rear seat back body panel 8a (conducted to the body panel 8), Filter elements 62R and 62L, such as capacitor filters, are interposed to reduce noise.

By wiring the wire harness in this way, the wire harness 4 connected to the defogger
5R, 45L, 61, 56, 69R and 69L
(This is collectively referred to as the defogger wire harness 11b) and the electrical equipment wire harness 11a can be separated, so that the noise signal superimposed on the electrical equipment wire harness 11a is transmitted to the defogger wire harness 1.
1b is prevented.

Here, when the capacitors 62R and 62L are inserted on the output side of the defogger sensor amplifier 55, that is, in the defogger wire harness 11b, it has been experimentally found that the effect of inserting the capacitors is not so great. In addition, the defogger wire harness at the rear of the vehicle from the rear seat back panel 8b is wired on the top surface of the tray panel 46, and the electrical wiring harness is wired on the bottom surface of the tray panel 46, so that the tray panel 46 has a shielding effect. You can have it.

The defogger wire harness 11b and the electrical equipment wire harness 11a form a main harness 20 in the dash side portion shown in FIG. Most can be avoided.

Although the noise is slight, the noise induced in the main harness on the side of the dash is between the wire harness 61 and the wire harnesses 45R and 45L connected to the rear differential hog 42 in the defogger wire harness 11b. An inductor filter 47 is connected to the rear defogger sensor 48, and capacitor filters 62R and 62L as noise prevention filter elements are connected to the wire harnesses 69R and 69L of the rear defogger sensor 48 near the input terminal of the defogger sensor amplifier 55 to ground the body. By doing so, it is possible to remove even a slight amount of noise superimposed on the defogger wire harness 11b.

Note that as the filter elements 62R and 62L used here, it is preferable to use ceramic capacitors with a capacitance of about 0.001uF to 0.1uF from a cost standpoint, and if the capacitance is smaller than this, the filter effect will be reduced. Moreover, if the capacitance becomes larger than this, there is a possibility that the operation of the sensor amplifier will be adversely affected.

In addition, the input wire harness 61 to the inductor filter 47 is connected to the output side wire harnesses 45R and 45L of the inductor filter 47 as in the conventional case.
If the wire harness 61 is pulled out from the rear of the vehicle and bundled together, the filter effect of the inductor filter 47 will be canceled due to the induction of noise between the input and output lines. Pull out the wire harnesses 45R and 45L as shown in FIG.
The output lines to the filter case are respectively taken out from the opposing surface of the filter case.

Note that the above is a way to prevent noise from entering the car radio by wiring the wire harness behind the darts side, but noise may be caused by other paths of noise, such as direct radiation from the instrument harness. Possible causes include noise entering the radio antenna.

However, it has been confirmed through experiments that the noise from such a path is extremely slight. Therefore, in order to effectively reduce radio noise, the above-mentioned wiring method and interposition of a filter are sufficient.

Furthermore, since a shielded wire (not shown) is used from the antenna output terminal AT (see FIG. 6) to the in-vehicle radio (not shown), noise will not be mixed in from the shielded wire.

FIG. 12 is a comparison diagram of noise measured at the terminals of a radio speaker.

Here, the horizontal axis lists the operations of in-vehicle electrical components as noise generation sources. The vertical axis indicates the magnitude of the generated noise expressed in terminal voltage (VP-P) at the speaker terminal of the radio. Moreover, the black circles are the measured values of noise according to the conventional example, and the white circles are the measured values of noise according to the embodiment of the present invention.

Note that the displayed values are average values measured at several points in three AM broadcast band frequencies, and the arrows indicate the noise reduction effect achieved by implementing the present invention.

As is clear from this figure, the level of noise generated in the radio by various in-vehicle electrical components is uniformly reduced by employing the wiring method according to the present invention.

As explained above, according to the present invention, when wiring a wiring harness for a vehicle that has a rear differential, various lamps, electrical components such as various motors, and a radio antenna, it is possible to wire the wiring harness for a vehicle that has a rear differential, various lamps, electric components such as various motors, and a radio antenna without connecting the ground of various lamps to the body panel. Wire the wires to the negative terminal of the battery via the lead wire, and separate the defogger wire harness associated with the rear defogger and the electrical wiring harness connected to the electrical components at the rear of the dash side to prevent noise radio waves from the body panel and defogger. prevent exposure to radiation.

In addition, when wiring a wire harness for a vehicle that has a radio antenna that is close to or integrated with the rear defogger on the rear window, it is also necessary to wire the wiring harness between the defogger wire harness and the body panel, preferably each wire harness connected to the defogger sensor. Just before connecting to the defogatsuga sensor amplifier,
By interposing a noise prevention filter element between each wire harness and the body panel, the very slight noise induced in the defogger wire harness can be further reduced.

Therefore, the noise that enters the car radio can be significantly reduced without having to select and insert a noise suppressor for each individual electrical component as in the past.

It goes without saying that this invention can be applied to any of these types of vehicles, and this eliminates the need for noise countermeasures for each vehicle type and electrical component, which was required in the past, and also contributes to shortening the development period for new models. do.

[Brief explanation of the drawing]

Figures 1 to 7 are diagrams for explaining the conventional wiring harness wiring method. Figure 1 is a sketch of the wire harness wiring at the rear of the trunk of the vehicle, and Figure 2 is the wiring for the combination lamp. Figure 3 is a diagram of the wire harness wiring in the rear parcel area in front of the trunk of a vehicle that has a whip antenna in the rear fender.
Wire harness wiring diagram on the right side of the darts,
FIG. 5 is a wiring harness wiring diagram of a body part, and FIGS. 6 and 7 are wiring harness wiring diagrams of a rear parcel part of a vehicle having a rear differential camera and a radio antenna on a rear window. 8 to 11 are diagrams for explaining an embodiment of the present invention, FIG. 8 is a wiring diagram of a combination lamp, and FIG. 9 is a front view of a trunk room of a vehicle having a radio antenna in the rear fender. , FIG. 10 is a wiring harness wiring diagram for the body portion, and FIG. 11 is a wiring harness wiring diagram for the rear parcel portion of a vehicle having a rear differential camera and a radio antenna on the rear glass. FIG. 12 is an explanatory diagram comparing the measured values of noise generation in an in-vehicle radio between wire harness wiring according to the conventional method and wire harness wiring according to the method of the present invention. B...Battery, 1...Trunk room, 6
R, 6L...Rear combination lamp, 8...
...Body panel, 10R, 10L...Rear speaker, 11...Body harness, 11a...Electrical wiring harness, 11b...Default power supply wire harness, 14...Trunk room lamp, 20...
Main harness, 41...Radio antenna, 42
...Rear differential, 43...Rear glass, 46
...Tray panel, 47...Inductor filter, 48...Defogger sensor, 51...Air purifier, 55...Defogger sensor amplifier, 60...
...Lead wire, 62R, 62L...Filter element.

Claims (1)

[Claims] 1. When wiring a wiring harness for a vehicle that has a rear differential, various lamps, electric components such as various motors, and a radio antenna, the ground side of the various lamps is not connected to the body panel. The wiring is routed to the negative terminal of the battery via the lead wire, and the defogger wire harness associated with the rear defogger and the electrical equipment wire harness connected to the electrical component are separated from each other at least in a region rearward of the vehicle from the dashboard side. A wiring harness wiring method characterized by: 2. When wiring a wiring harness for a vehicle that has a rear differential camera, electrical components such as various lamps and various motors, and a radio antenna that is installed in the rear window and is adjacent to or integrated with the rear differential camera, the ground side of the various lamps should be without connecting it to the body panel, wire it to the negative terminal of the battery via the lead wire, and connect the differential gear wire harness associated with the rear differential gear and the electrical equipment wire harness connected to the electrical component at least to the rear of the vehicle from the side of the dash. 1. A method of wiring a wire harness, characterized in that the wires are laid apart from each other in the parts, and a noise prevention filter element is interposed between the defogger wire harness and the body panel.