Information
-
Patent Grant
-
6310293
-
Patent Number
6,310,293
-
Date Filed
Wednesday, December 22, 199924 years ago
-
Date Issued
Tuesday, October 30, 200122 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Reichard; Dean A.
- Estrada; Angel R.
Agents
- Bierman, Muserlian and Lucas
-
CPC
-
US Classifications
Field of Search
US
- 174 99 B
- 174 682
- 174 70 B
- 174 71 B
- 174 72 B
- 174 149 B
- 174 151
- 361 611
- 361 648
-
International Classifications
-
Abstract
An insulative plate is fixed to a bus bar stacked substrate by inserting projection formed on the bus bar into projection entry section, shaped like a covered box, on the insulative plate. By pressing the insulative plate onto the bus bar stacked substrate the projection is pushed into the projection entry section and the insulative plate is securely fixed to the bus bar.
Description
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The present invention relates to a stacked assembly having a bus bar and, more particularly, to an arrangement wherein a top insulating plate is securely held to the lower substrate without the need for welding.
2. Art Relating to the Invention
Conventionally, electrical connection boxes are used as connection junction points for wire harnesses and the like while also housing various electronic circuits, electronic components, and the like for automobiles.
Electrical connection boxes often house a stacked assembly as shown in FIG.
5
. In
FIG. 5
, stacked assembly
51
includes bus bar stacked substrate
52
, insulative plate
53
, and plurality of solid-core wires
54
. Bus bar stacked substrate
52
forms one portion of an internal circuit and includes a plurality of stacked insulative substrates
56
,
57
,
58
. Bus bars
61
are fixed above the insulative substrate
56
, between insulative substrates
56
,
67
,
58
, and below insulative substrate
58
. Bus bars
61
include plate-shaped bus bar tabs
62
, which are bent perpendicular to both the direction in which bus bars
61
are laid, and supporting bus bar tabs
63
. Bus bar tabs
63
have sections
63
a
which form a pincer shape for connecting to solid core wires
54
.
Insulative plate
53
is mounted on top of a portion of bus bar stacked substrate
52
. Insulative plate
53
is formed in a plate shape that covers a portion of insulative substrate
56
that portion being the part that has bus bar tabs
63
. Tab holders
66
are formed in insulative plate
53
and align with bus bar tabs
63
. Tab holders
66
are formed with tab insertion openings
69
, which have widths that are slightly greater than the widths of bus bar tabs
63
. When insulative plate
53
is mounted on bus bar stacked substrate
52
, bus bar tabs
63
are inserted through tab insertion openings
69
. When this is done, the ends of supporting sections
63
a
are projected from the upper end of tab holder
66
.
Solid-core wires
54
are connected to bus bar tabs
63
. In this process of assembly, the insulative covering on solid-core wire
54
is cut away by supporting section
63
a
, thus forming an electrical connection between solid-core wire
54
and bus bar tab
63
.
With the above operation, bus bar
61
and solid-core wire
54
are electrically connected, and an electrical circuit is formed on the upper surface of insulative plate
53
, thus forming the internal circuit in stacked assembly
51
.
Stacked assembly
51
is interposed and loosely fixed between an upper case and a lower case (not shown in the figure) and is housed inside the electrical connection box.
One of the problems associated with stacked assembly
51
is that insulative plate
53
can disengage from bus bar stacked substrate
52
thereby also disengaging solid-core wires
54
. This can result in time-consuming operation of re-wiring solid-core wires
54
.
Also, stacked assembly
51
, housed in the electrical connection box, is only loosely held by the upper case and the lower case. Thus, bus bar stacked substrate
52
and insulative plate
53
can become misaligned due to the leeway provided by the clearance and the vibrations that are inherent in an automobile when it is being operated. This can lead to bad connections between bus bars
61
and solid-core wires
54
. This also requires re-wiring solid-core wires
54
.
One measure that has been taken to prevent these types of bad connections is to weld bus bar substrate
52
to insulative plate
53
. However, this requires special equipment to perform welding and also requires a larger number of production steps for the welding operation, leading to increased production costs. Furthermore, extra space is required to provide for welding spots, leading to larger dimensions for stacked assembly
51
.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a stacked assembly that can prevent interruptions and delays of production operations, that can reduce production costs, and that can provide a more compact design.
In order to achieve the objects, the present invention provides a stacked assembly comprising a bus bar substrate including a bus bar fixed to an insulative substrate; and an insulative plate having an upper surface on which an electrical circuit is formed, a plurality (two or more) of projections are formed from the bus bar and extend upwardly above the insulative substrate, projection entry sections are formed on the insulative plate and correspond in location and number to the projections on the insulative substrate, such that the insulative plate is fixed onto the bus bar substrate by having the projections mate with the projection entry sections.
Preferably, the stacked assembly has two projections and those two projections are positioned on the bus bar substrate at points which correspond to the opposite corners of the insulative plate.
More preferably, there are four projections, one corresponding to each corner of the insulative plate.
It is also preferred that the projection entry sections on the insulate plate fully enclose and insulate the projections to prevent contact with the wire cores which are mounted on the insulative plate.
According to the present invention, the insulative plate is pressed against the bus bar substrate so that the projections are pushed into the projection entry section, thus reliably fixing the plate onto the bus bar substrate. As a result, interruptions and delays in assembly resulting from the bus bar substrate disengaging from the insulative plate are avoided.
Also, the need for dedicated equipment required for fixing the insulative plate onto the bus bar substrate through welding is eliminated, thus reducing the number of production steps. As a result, production costs can be reduced.
Furthermore, the need for extra space on the stacked assembly for weld spots is eliminated. This allows the stacked assembly and the electrical connection box to be made more compact.
Another advantage of the present invention is that the projections are formed from the bus bar. This provides a cost savings to the manufacture in that the bus bar is already present in the substrate assembly and no additional elements need be added.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects of the present invention may be more fully understood by reference to one or more of the following drawings wherein:
FIG. 1
is an exploded perspective drawing showing an embodiment of the stacked assembly according to the present invention;
FIG. 2
is a cross-section drawing of the same embodiment;
FIG. 3
is a cross-section drawing of the same embodiment;
FIG. 4
is a cross-section drawing showing another embodiment of a stacked substrate according to the present invention; and
FIG. 5
is an exploded perspective drawing showing a conventional stacked assembly.
DETAILED DESCRIPTION OF THE INVENTION
The following is a description, with references to FIG.
1
through
FIG. 3
, of an embodiment of a stacked assembly housed in an electrical connection box according to the present invention.
FIG. 1
shows an exploded perspective drawing of a stacked assembly according to the present invention. In
FIG. 1
, stacked assembly
11
includes bus bar stacked substrate
12
, insulative plate
13
, and a plurality of solid-core wires
14
.
Bus bar stacked substrate
12
forms a part of an internal circuit and includes a plurality of insulative substrates
16
,
17
,
18
. Ribs
16
a
,
16
b
are formed on the upper portion and the lower portion of the upper perimeter of insulative substrate
16
, respectively. Ribs
17
a
,
18
a
are formed on the lower portions of the outer perimeters of insulative substrates
17
,
18
. Bus bars
21
are fixed above and below insulative substrate
16
and below insulative substrates
17
and
18
in the space formed by ribs
16
a
,
16
b
,
17
a
,
18
a
, when insulative substrates
16
,
17
,
18
are stacked. Bus bars
21
are formed with plate-shaped bus bar tab
22
bent perpendicular to the direction in which bus bar
21
is laid and pincer-shaped bus bar tab
23
having supporting section
23
a
for making an electrical contact with solid-core wire
14
. Bus bar tab
22
is used for connections with electronic components.
Each bus bar
21
which is fixed on top of insulative substrate
16
is formed with plate-shaped projection
31
bent perpendicular to the direction in which bus bar
21
is laid (see FIGS.
1
and
2
). Similarly, each bus bar
21
fixed below insulative substrate
16
is formed with plate-shaped projection
32
which extends upwardly through insulative substrate
16
(see FIGS.
1
and
3
). Tapered sections
31
a
and
32
a
are formed at the ends of projections
31
,
32
and serve as guides for projections
31
,
32
in the projection entry sections.
Insulative plate
13
is mounted on bus bar stacked substrate
12
. Insulative plate
13
is formed in a plate shape that covers that portion of insulative substrate
16
, which has bus bar tabs
23
and projections
31
,
32
. Tab holders
36
and projection entry sections
37
,
38
are formed so that they are aligned with the positions of bus bar tabs
23
and projections
31
,
32
, respectively.
Referring now to
FIGS. 2 and 3
, tab holders
36
are projected upright from insulative plate
13
. The inner wall surfaces thereof are formed smoothly going downward from the outside toward the center. Tab holders
36
are formed with tab insertion openings
39
, which have widths that are slightly wider than the widths of bus bar tabs
23
. When insulative plate
13
is mounted on bus bar stacked substrate
12
, bus bar tabs
23
are inserted into tab insertion openings
39
. When this is done, the ends of supporting sections
23
a
project slightly from the upper ends of tab holders
36
.
Projection entry sections
37
,
38
are projected upright from insulative plate
13
and are shaped like covered boxes so as to insulate projections
31
,
32
. The inner walls thereof are formed with widths that correspond to the widths of projections
31
,
32
.
Tapered sections
37
a
,
38
a
are formed in the lower end of the inner walls of projection entry sections
37
,
38
. When insulative plate
13
is pressed against bus bar stacked substrate
12
, projections
31
,
32
are inserted into projection entry sections
37
,
38
. When this takes place, projections
31
,
32
are guided inside projection entry sections
37
,
38
by the interaction between tapered sections
31
a
,
32
a
and tapered sections
37
a
,
38
a
. With projections
31
,
32
pressed into the projection entry sections
37
,
38
respectively, insulative plate
13
is fixed to bus bar stacked substrate
12
without the need for welding.
Single-core wires
14
are connected to bus bar tabs
23
by guiding single-core wire
14
onto supporting section
23
a
, which project slightly from the upper end of tab holder
36
. When this takes place, the insulative cover of single-core wire
14
is cut away by supporting section
23
a
thereby forming an electrical connection between single-core wire
14
, bus bar tab
23
and bus bar
21
.
Thus, bus bar
21
and single-core wire
14
are electrically connected, an electronic circuit is formed on the upper surface of insulative plate
13
, and an internal circuit is formed in stacked assembly
11
.
Stacked assembly
11
is loosely fixed between an upper case and a lower case, not shown in the figures, and is then housed inside an electrical connection box.
As will be appreciated from the above discussion of the invention, work delays can be avoided. In the present invention, insulative plate
13
is pressed onto bus bar stacked substrate
12
, projections
31
,
32
are inserted into projection entry sections
37
,
38
, and insulative plate
13
is reliably fixed onto bus bar stacked substrate
12
. Thus, insulative plate
13
is prevented from disengaging from bus bar stacked substrate
12
, and delays and interruptions in work caused by bad connections between bus bars
21
and single-core wire
14
can be avoided.
It should also be noted that projections
31
,
32
are oriented in the same manner as bus bar tabs
23
. This prevents movement of insulative plate
13
in one direction and assists in alignment of single-core wire
14
with bus bar tabs
23
.
In addition, the assembly process is simplified. Tapered sections
31
a
,
32
a
,
37
a
,
38
a
are formed on projections
31
,
32
and in projection entry sections
37
,
38
, respectively. This allows projections
31
,
32
to be inserted quickly and smoothly into projection entry sections
37
,
38
. Also, because of the gap between the side walls of projections
31
,
32
and projection entry sections
37
,
38
along the other axis, easy mating is also provided between the two elements.
Also, the internal circuit can be formed through a combination of bus bars
21
and single-core wires
14
, thus increasing the degree of freedom provided for circuit design.
The embodiments of the present invention is not restricted to the embodiment described above, and the following modifications may also be implemented:
In the embodiment described above, the single-core wires laid on the upper surface of insulative plate
13
form an electrical circuit on this upper surface. However, the electrical circuit on the upper surface of an insulative plate can be formed using different bus bars fixed to this upper surface; or the electrical circuit can be formed using a printed circuit board.
In the embodiment described above, tapered sections
31
a
,
32
a
,
37
a
,
38
a
are formed on projections
31
,
32
and projection entry sections
37
,
38
, respectively. However, similar tapered sections can be formed only on either projections
31
,
32
or projection entry sections
37
,
38
. Furthermore, these tapered sections are not necessary.
In the embodiment described above, projections
31
,
32
are formed on bus bars
21
fixed to the top or below insulative substrate
16
. However, projections can be formed on a plurality of bus bars
21
selected from a single layer if a plurality of bus bars
21
are fixed at the same layer, or from the lowest level, like projection
45
in FIG.
4
.
In the embodiment described above, projections
31
,
32
are formed on bus bars
21
fixed above and below insulative substrate
16
. However, a plurality of projections can be formed only on a single selected bus bar
21
.
In the embodiment described above, two projections
31
,
32
are formed, but any number of projections can be formed as long as there is a plurality.
While only a limited number of specific embodiments of the present invention have been expressly disclosed, it is, nonetheless, to be broadly construed, and not to be limited except by the character of the claims appended hereto.
Claims
- 1. A stacked assembly comprising a stacked substrate including at least one bus bar fixed to an insulative substrate, an insulative plate having an upper surface with an electrical circuit thereon,a plurality of projections formed from and extending from said bus bar, a corresponding plurality of projection entry sections on said insulative plate, said insulative plate fixed onto said stacked substrate by said projections inserted into said projection entry sections, wherein said projection entry sections cover said projections when said projections are inserted into said projection entry sections.
- 2. The stacked assembly of claim 1 wherein there is a plurality of bus bars fixed to said insulative substrate.
- 3. A stacked assembly comprising a stacked substrate including a plurality of bus bars fixed to a plurality of insulative substrates, an insulative substrate having an upper surface on which an electrical circuit is formed,at least two of said bus bars having projections which are formed from and extending upward from said bus bar projection entry sections on an insulative plate corresponding to said projections in number and location, said insulative plate being fixed onto said stacked substrate by said projections in said projection entry sections, wherein said projection entry sections cover said projections when said projections are inserted into said projection entry sections.
Priority Claims (1)
Number |
Date |
Country |
Kind |
10-366949 |
Dec 1998 |
JP |
|
US Referenced Citations (4)
Foreign Referenced Citations (3)
Number |
Date |
Country |
2318226 |
Mar 1995 |
GB |
2293052 |
Mar 1995 |
GB |
2103723 |
Aug 1990 |
JP |