JP2002301998A - Earth connection structure for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve efficiency of installation and connection of an earthing wire harness and to simplify them. SOLUTION: A mounting part 11 of an engine control unit 10 connected to a wire harness W/H-10 is formed of a conductive material, an earthing bus bar 13b electrically connected to the mounting part 11 is formed in an internal circuit 13, and earth wires d11-d13 are included in the wire harness W/H-10 and connected to the bus bar 13b to electrically connect them to the mounting part 11. The control unit 10 is mounted to a body panel P through the mounting part 11, and thus the wire harness W/H-10 is connected to the body panel P for earthing it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth connection structure for a motor vehicle, and more particularly, to an overall earth circuit in a vehicle body for realizing an efficient earth circuit.

[0002]

2. Description of the Related Art Various electrical components mounted on a vehicle are connected by a wire harness routed on a vehicle body to form a required electric circuit. These electric circuits include an earth circuit that is electrically grounded. The earth circuit is formed by connecting a wire harness for earth connection to a vehicle body panel.

FIGS. 4 (A) and 4 (B) show a ground connection structure to a vehicle body panel P in a conventional ground circuit. A wire harness W / H for ground connection uses a ground joint connector J / C at a terminal. Are combined. The ground joint connector J / C is a terminal J / C- made of conductive material.
1 and protrude, and a bolt hole J / C-1a is inserted into the terminal J / C-1.
And a protrusion J / C-1b for preventing rotation at the tip
Is protruding.

On the other hand, the ground connection portion Pa of the vehicle body panel P is provided with a screw hole portion Pb and a hole portion Pc, and the terminal portion J / C-
No. 1 projection J / C-1b is inserted into the hole Pc, and the bolt B is inserted into the bolt hole J / C-1a to insert the screw hole Pb.
To the ground joint connector J / C
Is attached to the vehicle body panel P. By this attachment, the wire harness W / H is electrically connected to the vehicle body panel P via the terminal portion J / C-1 of the joint connector J / C and is grounded. In some cases, a ground terminal may be attached to the terminal of the wire harness W / H to connect the ground to the vehicle body panel P.

FIG. 5 shows an earth circuit of a portion related to the earth connection. The lights L and switches SW as electric components mounted on the vehicle body, an engine control unit (ECU) 1 as an on-vehicle unit, and an anti-lock brake device. Ground wire d extending from control unit 2 of (ABS)
A wire harness W / H constituted by 1 to d4 is connected to a ground joint connector J / C. Since the ground joint connector J / C is electrically connected to the vehicle body panel P, the ground wires d1 to d4 are also grounded.

[0006] In addition to the above, the on-vehicle unit includes a control unit of a traction control device (TRC), an electric connection box, a relay box, and the like. The housings of these in-vehicle units, such as covers and cases, are molded of resin.
It is integrally formed of resin and attached to the vehicle body panel via bolts or the like via this attachment portion.

[0007]

As described above, in the conventional ground connection, the wire harness W / H for ground connection is routed and routed to the ground connection portion Pa provided on the vehicle body panel P. There is a problem that the length of d1 to d4 becomes longer and there is a routing portion used only for ground connection, which complicates the wiring of the harness, and requires much labor for the routing work.

Further, it is necessary to provide the ground connection portion Pa independently on the vehicle body panel P, and there is a problem that the processing of the vehicle body panel P requires time and effort. Furthermore, if the vehicle body is a small car, if the wiring of the grounding harness is complicated as described above, it becomes difficult to secure the ground connection portion Pa in the wiring space and the vehicle body panel P due to the layout. There are many.

In addition, the ground connection work is difficult because the terminal J / C-1 or the ground terminal of the ground joint connector J / C to be attached to the terminal of the wire harness W / H is small in size, so that the bolt fastening work is also difficult. There is a problem that takes time. In particular, in the case of a small car or the like, the work space around the ground connection portion Pa is also limited, so that the above-mentioned work becomes more difficult.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has reviewed the ground circuit in the vehicle body as a whole, and effectively utilizes a vehicle-mounted unit mounted on a vehicle body panel to route and connect the ground circuit. The challenge is to improve efficiency.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a vehicle-mounted unit which is connected to a wire harness of an external circuit and is formed of a conductive material on a vehicle body panel. In addition, while providing an earth circuit portion that is electrically connected to the mounting portion, a ground wire is included in a wire harness connected to the on-vehicle unit and connected to the ground circuit portion, so that the ground wire is connected through the mounting portion. A ground connection structure for an automobile is provided, which is configured to be grounded to a vehicle body panel.

When the vehicle-mounted unit is formed as described above,
Since the vehicle-mounted unit is always mounted to the vehicle body panel via the mounting portion, the ground circuit provided in the internal circuit can be electrically connected to the vehicle body panel through the conductive material mounting portion. On the other hand, if the ground wire is included in the wire harness connected to the vehicle-mounted unit and connected to the ground circuit of the vehicle-mounted unit,
The ground wire and the vehicle body panel are conducted to easily form a ground circuit.

[0013] By forming the ground circuit with the vehicle body panel in this manner, the wiring portion required only for the conventional ground circuit can be greatly reduced, and the joint connector and the ground terminal for connection to the vehicle body are not required. This eliminates the need to provide a separate ground connection on the vehicle body panel. As a result, complicated earth connection work can be eliminated and efficient earth connection can be achieved, and the cost of earth connection can be greatly reduced by reducing the amount of harness and the number of required operations. The ground connection via such an in-vehicle unit may be performed at a plurality of locations via a plurality of in-vehicle units as well as at one location.

The on-vehicle units are an engine control unit, a control unit for an anti-lock brake device, a control unit for a traction control device, an electric connection box, a relay box, and a fuse box.
By using such various in-vehicle units for ground connection, ground connection can be made to the vehicle body panel via the nearest on-vehicle unit, and the harness length required for the ground circuit and the wiring space for ground are reduced. It can be further reduced. Depending on the type of vehicle to be applied, all the on-vehicle units mounted may be used for ground connection, or the ground connection may be made only via the on-vehicle unit located at an appropriate location for ground connection.

These on-vehicle units include a bus bar,
The internal circuit is composed of electric wires, printed circuit boards, etc., and the ground circuit can also be formed of bus bars, electric wires, printed circuit boards, etc., especially if a bus bar can be used. is there.

The on-vehicle unit is provided with a ground connection for conducting to the ground circuit, and a unit connection for connection to a unit circuit for ensuring the function of the on-vehicle unit of the internal circuit. The harness is
It is preferable that the ground wire harness be composed of a ground wire harness composed of a ground wire and a unit wire harness that ensures the function of the vehicle-mounted unit, and that the ground wire harness be connected to the ground connection portion.

With the above arrangement, the internal circuit of the on-vehicle unit can be clearly divided into the ground circuit unit and the unit circuit unit, so that the reliability of the circuit can be improved and the circuit layout and the like can be facilitated. In addition, if the number of wire harnesses connected to the on-vehicle unit is also divided into two and divided into a ground wire harness and a unit wire harness, the purpose of use of each wire harness will be clear, and it will be easier to arrange the wiring harness for each application. In particular, when the number of electric wires required for connection is large, complication can be prevented.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. Note that the same reference numerals are given to the same electrical components and the like as those in the related art. FIGS. 1A and 1B show a vehicle ground connection structure according to a first embodiment of the present invention, in which a wire harness W / H-1 includes ground lines d11 to d13 in an engine control unit 10 as a vehicle-mounted unit.
0, and is grounded to the vehicle body panel P.

The engine control unit 10 has a mounting portion 11 made of a conductive material having a screw hole 11a and a projection 11b from the upper surface 10b of a box-shaped housing 10a.
Is protruding. In the housing 10a, a CPU (Central Processing Unit) 12 for control calculation is provided.
12 and the strip-shaped bus bar 13a to connect the internal circuit 1
3 is formed. These bus bars 13a are connected to connector portions 10d provided on the lower surface 10c of the housing 10a.
It is connected to the terminal 14A housed inside.

The internal circuit 13 is also provided with a ground bus bar 13b which is connected to the mounting portion 11 to form a ground circuit portion.
d, and the CPU 1
It is also connected to the second ground contact 12a.

On the other hand, the engine control unit 10
Wiring harness W / H-10 which is an external circuit connected to
In addition to the plurality of ground wires d11 to d13, signal input / output wires for ensuring the function of engine control of the engine control unit 10 are bundled.
Further, a connector 15 that is connected to the connector portion 10d of the engine control unit 10 by a connector is attached to an end of the wire harness W / H-10 via a terminal 16 of a wire terminal.

The mounting portion of the engine control unit 10 of the vehicle body panel P on the vehicle body side is substantially the same as the conventional ground connection portion Pa. A hole Pe and a screw hole Pd are formed by bolts B. The engine control unit 10 is attached.

For ground connection to the vehicle body panel P, first, the wire harness W / H-10 is connected to the engine control unit 10 by coupling the connector portion 10d and the connector 15. With this connection, the CP of the internal circuit 13 is
U12 and the signal input / output wires of the wire harness W / H-10 are electrically connected, and the ground wires d1 to d3 are connected to the mounting portion 11 via the ground bus bar 13b through the connection of the terminal 16 and the ground terminal 14B. Conducted.

In this state, the bolt B is inserted into the bolt hole 11a of the mounting portion 11 and fastened to the screw hole Pd of the vehicle body panel P, and the engine control unit 10 is mounted on the vehicle body panel P. With this mounting, the mounting portion 11 and the vehicle body panel P are kept in contact with each other, and become conductive,
As a result, the ground wires d11 to d13 are also grounded to the vehicle body panel P via the mounting portion 11, thereby forming a ground circuit.

FIG. 2 shows a ground circuit for the above-described ground connection, which corresponds to the conventional ground circuit of FIG.
, The earth joint connector J / C and the earth connection part Pa of the vehicle body panel P are abolished, and an independent earth connection work to the vehicle body panel P is not required. The wire harness W / H-10 itself is
Compared to the wire harness W / H-1, the configuration is simplified at each location and the length of the harness is reduced, such that the ground wire d4 extending from the conventional engine control unit 1 becomes unnecessary.

The ground connection structure for the vehicle body panel P according to the present invention includes a control unit for an antilock brake device, a control unit for a traction control device,
The present invention is also applicable to other on-vehicle units such as an electric connection box (including a junction box), a relay box, and a fuse box.

Also in this case, the mounting portion of each vehicle-mounted unit to the vehicle body panel is formed of a conductive material.
By providing an earth circuit portion that is electrically connected to the mounting portion in the internal circuit, it is possible to connect the wire harness to the in-vehicle unit and connect the ground to the vehicle body panel via the in-vehicle unit. Incidentally, the ground connection to the vehicle body panel in such a form may be singular or plural.
Since it can be connected to the body panel at the closest location,
Harness wiring required for ground connection has been further simplified. Further, the ground circuit portion can be formed of an electric wire, a printed circuit board, or the like in addition to the bus bar according to the internal circuit.

FIGS. 3 (A) and 3 (B) show a ground connection structure to a vehicle body panel according to a second embodiment of the present invention. The engine control unit 20 is connected to an engine control unit 20 which is a vehicle-mounted unit. Wire harness W for unit that sends and receives signals for securing functions
/ H-11 and the ground wire harness W / H-12.

The engine control unit 20 has a housing 20a corresponding to a plurality of wire harness connections.
Connector portion 2 as a unit connection portion on the lower surface 20c of the
A second connector portion 20f is provided on the side surface 20e as a ground connection portion, and a mounting portion 21 made of a conductive material protrudes from the upper surface 20b as in the first embodiment.

The internal circuit 23 is provided with a strip-shaped bus bar 23a connected to the CPU 22, forms a unit circuit portion 23c, and connects the bus bar 23a to a terminal 24A housed in the first connector portion 20d. Also, the internal circuit 23
Is provided with an earth bus bar 23b and
d, the mounting portion 21, the CPU ground contact 22a,
And a ground terminal 2 housed in the second connector portion 20f
4B.

Unit wiring harness W / H-11
Is connected to the first connector section 20d via a terminal connector, and is connected to the unit circuit section 23c.
The grounding wire harness W / H-12 is dedicated to grounding connection consisting of only a plurality of grounding wires d21 to d24 extending from various electric components mounted on the vehicle body and other on-vehicle units. The two connector portion 20f and the terminal connector are connected to each other via a terminal connector to form a ground circuit portion 23d.
Through the mounting portion 21.

The attachment of the engine control unit 20 to the vehicle body panel P is performed in the same manner as in the first embodiment.
It is bolted through. With this mounting, the ground wire harness W / H-12 is electrically connected to the vehicle body panel P and is grounded. As described above, in the ground connection structure of the second embodiment, the plurality of wire harnesses connected to the engine control unit 20 are divided into those for the ground and those for the unit. In addition, since the internal circuits can be clearly distinguished, the layout configuration and the like of the internal circuits are also facilitated.
When the number of necessary connection circuits is large, the number of wire harnesses W / H may be further increased. In this case, an internal circuit is also formed according to the increased connection form of the harness.

Further, the ground connection structure of the second embodiment is also a control unit of an anti-lock brake device, a control unit of a traction control device, an electric connection box (including a junction box), a relay box, and a fuse box, which are other on-vehicle units. Etc. can be applied to other on-vehicle units.

[0034]

As is apparent from the above description, the use of the vehicle ground connection structure of the present invention makes it possible to eliminate the conventionally required ground joint connector and the dedicated ground connection portion of the vehicle body panel. The work of connecting the ground to the independent body panel can be eliminated. In addition, it is possible to partially shorten the length of the honeys required for the ground connection and to omit the ground wire, thereby simplifying the configuration and wiring configuration of the wire harness for the ground connection. In particular, when a plurality of ground connection structures according to the present invention are provided on a vehicle body, the ground connection can be made at a familiar place, and the circuit configuration of the ground connection can be further simplified.

Further, since an independent ground connection portion of the vehicle body panel is not required, the degree of freedom in layout design of other devices is increased, and a space for mounting other devices is easily secured, and the space for the vehicle body can be easily secured. The workability of mounting parts can also be improved.
In addition, the cost for ground connection can be significantly reduced by eliminating the ground joint connector and shortening the length of the harness.

[Brief description of the drawings]

FIG. 1 is a perspective view of a ground connection structure of a vehicle according to a first embodiment of the present invention, in which (A) is a perspective view of a ground connection state to a vehicle body panel via a vehicle-mounted unit, and (B) is a connection state of an internal circuit. FIG.

FIG. 2 is a ground circuit diagram of the first embodiment.

FIG. 3 is a perspective view of a ground connection structure of a vehicle according to a second embodiment of the present invention, in which (A) is a perspective view of a ground connection state to a vehicle body panel via a vehicle-mounted unit, and (B) is a connection state of an internal circuit. FIG.

FIGS. 4A and 4B are schematic diagrams of a conventional structure for connecting a ground to a vehicle body panel.

FIG. 5 is a conventional ground circuit diagram.

[Explanation of symbols]

 Reference Signs List 10 engine control unit 10d connector part 11 mounting part 12 CPU 13 internal circuit 13b bus bar for grounding W / H-10 wire harness d11-d13 ground wire

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H02G 3/38 H02G 15/08 J 15/08 3/28 F F term (reference) 5G355 AA03 BA01 BA12 5G361 BA01 BA03 BA06 BB01 BC01 5G363 AA16 BA02 DC02 5G375 AA02 BA03 CA02 CA19 CC07 DA36 DB11

Claims (3)

[Claims] A mounting portion for connecting the vehicle-mounted unit to the vehicle body panel, which is connected to a wire harness of an external circuit, is formed of a conductive material, and an internal circuit of the vehicle-mounted unit is provided with a ground circuit portion that is electrically connected to the mounting portion. An automobile having a configuration in which a ground wire is included in a wire harness connected to the vehicle-mounted unit and connected to the ground circuit section, whereby the ground wire is grounded to the vehicle body panel via the mounting section. Ground connection structure. 2. The vehicle ground connection according to claim 1, wherein the on-vehicle unit is an engine control unit, a control unit for an anti-lock brake device, a control unit for a traction control device, an electric connection box, a relay box, and a fuse box. Construction. 3. The on-vehicle unit is provided with a ground connection portion that conducts to the ground circuit portion, and a unit connection portion that connects to a unit circuit portion that ensures the function of the on-vehicle unit of the internal circuit. The wire harness is composed of a ground wire harness made of a ground wire and a unit wire harness that secures the function of the vehicle-mounted unit. The ground wire harness is connected to the ground connection portion and the unit wire is connected to the ground wire. The vehicle ground connection structure according to claim 1 or 2, wherein a harness is connected to the unit connection portion.