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BACKGROUND OF THE INVENTION
The present invention generally relates to a bus bar blank, bus bars formed
from the bus bar blank and a branch joint box including the bus bars and
more particularly, to bus bars mounted in a branch joint box, in which bus
bars of a plurality of patterns can be formed from one kind of a bus bar
blank molded from an identical die and a branch joint box in which the bus
bars of one pattern formed from the bus bar blank are mounted such that
efficiency for assembling the branch joint box is raised.
Conventionally, a plurality of kinds of bus bars are accommodated in a
branch joint box which is connected to intermediate portions of wiring
harnesses for a motor vehicle. Shapes of these bus bars, i.e., bus bar
patterns vary according to circuit configuration. When the bus bar
patterns are different from each other, the bus bar blanks have hitherto
been molded by different dies. Therefore, when there are a number of kinds
of the bus bar patterns, a number of kinds of dies are also required to be
prepared, thereby resulting in rise of production cost. When the bus bars
are mounted on the branch joint box, the bus bars having different shapes
are required to be attached to predetermined locations, respectively and
thus, assembly of the branch joint box is troublesome.
Meanwhile, in the branch joint box, a branch joint point is concentrated at
one spot so as to perform branch joint of wires reasonably and
economically. In response to recent rise of density of wiring harnesses,
branch joint boxes having various kinds of shapes are known.
For example, Japanese Utility Model Laid-Open Publication No. 4-131117
(1992) filed by the assignee assigned by the present inventors discloses a
branch joint box shown in FIGS. 1 to 3. In this known branch joint box, a
casing 73 is formed by upper and lower casings 71 and 72 which are formed
with connection openings 71a and 72a for a connector X, respectively. A
bus bar 74 is disposed between the upper and lower casings 71 and 72. The
bus bar 74 includes an elongated base portion 74a and a plurality of pairs
of tabs 74b arranged at a predetermined interval in a longitudinal
direction of the base portion 74a and extending from opposite sides of the
base portion 74a such that the tabs 74b project into the connection
openings 71a and 72a.
The upper and lower casings 71 and 72 are of identical shape. On upper and
lower faces of the casing 73, the connection openings 71a and 72a are
formed symmetrically. Hence, in this known branch joint box, even if the
connector X is connected to either one of the connection openings 71a and
72a of the upper and lower casings 71 and 72, an identical branch circuit
is formed. As a result, the connector X can be connected to the known
branch joint box without the need for paying attention to the upper and
lower faces of the casing 73.
However, the known branch joint box referred to above is structurally
complicated because the casing 73 is formed by two members, i.e., the
upper and lower casings 71 and 72. Meanwhile, since the upper and lower
casings 71 and 72 are molded by resin separately, resinous molding of the
upper and lower casings 71 and 72 should be performed a total of two
times, thereby resulting in rise of production cost. Furthermore, in the
known branch joint box, a case in which the upper and lower casings 71 and
72 have different shapes, respectively may happen. In this case, two kinds
of dies are required to be prepared, thereby resulting in further rise of
production cost due to increase of cost for the dies.
SUMMARY OF THE INVENTION
Accordingly, an essential object of the present invention is to provide,
with a view to eliminating the drawbacks inherent in prior art, a bus bar
blank molded by a single die, from which bus bars having a plurality of
patterns can be formed by properly cutting the bus bar blank such that
production cost of the bus bars is lowered and a branch joint box in which
the bus bar of one pattern are mounted such that efficiency for assembling
the branch joint box is raised.
Another important object of the present invention is to provide a branch
joint box which is simplified in structure so as to be produced at low
cost.
In order to accomplish the first object of the present invention, a bus bar
blank formed by punching an electrically conductive metal plate, according
to the present invention comprises: an elongated carrier; a plurality of
pairs of opposite coupling portions which extend orthogonally from
opposite sides of the carrier, respectively at a predetermined interval in
a longitudinal direction of the carrier; a pair of opposite connecting
portions which have a predetermined length and extend from a distal end of
each of the pairs of the opposite coupling portions in parallel with the
carrier; a pair of opposite first terminal portions which extend
orthogonally from the opposite connecting portions, respectively; a pair
of opposite second terminal portions which extend orthogonally from the
opposite connecting portions, respectively such that the first and second
terminal portions are disposed symmetrically with respect to a center of
the coupling portions; and a pair of opposite third terminal portions
which extend orthogonally from the opposite connecting portions,
respectively at a location outside the first and second terminal portions
and spaced a predetermined distance from one of the first and second
terminal portions or at locations outside the first and second terminal
portions and spaced the predetermined distance from the first and second
terminal portions, respectively; wherein the bus bar blank includes a
number of bus bar sets each including a pair of the opposite coupling
portions, a pair of the opposite connecting portions and a pair of the
opposite first, second and third terminal portions, wherein at a boundary
of neighboring ones of the bus bar sets, a boundary one of the first,
second and third terminal portions of one of the neighboring ones of the
bus bar sets lies next to an opposed boundary one of the first, second and
third terminal portions of the other of the neighboring ones of the bus
bar sets and a necessary gap is formed between the boundary one and the
opposed boundary one of the first, second and third terminal portions such
that a bus bar is formed from one of the bus bar sets or a plurality of
the bus bar sets by cutting the carrier; wherein by cutting off an
unnecessary one of the first, second and third terminal portions from the
bus bar, a bus bar of a different pattern can be formed.
Furthermore, the present invention provides a bus bar formed from the above
mentioned bus bar blank, wherein the first and second terminal portions
confront each other by bending the first and second terminal portions at
the connecting portions through 90.degree. and the third terminal portion
extends in parallel with the first and/or second terminal portion at a
predetermined distance therefrom.
Alternatively, the third terminal portion may be cut off from the bus bar.
Moreover, the present invention provides a branch joint box for
accommodating the bus bars referred to above, comprising: a pair of
connector coupling portions for receiving connectors, respectively, which
are provided on opposed faces of the branch joint box, respectively;
wherein a plurality of terminal holes are formed on each of the opposed
faces at identical positions of the opposed faces such that the first,
second and third terminal portions of the bus bars extend from the opposed
faces through the terminal holes.
In order to enable the bus bars of an identical pattern to be used for the
branch joint box, an interval of the terminal holes in a direction of a
centerline of the branch joint box is set to a pitch between the first and
second terminal portions of each of the bus bars and an interval of the
terminal holes in a direction perpendicular to the centerline is set to a
pitch between the first and third terminal portions of each of the bus
bars.
Meanwhile, in case a plurality of the connector coupling portions are
provided in parallel on each of the opposed faces of the branch joint box,
an interval of the connector coupling portions is set to a distance
between centers of neighboring ones of the connector coupling portions.
The casing of the branch joint box is formed by the upper and lower casings
of an identical shape by over-turning one of the upper and lower casing is
upside down. The coupling portions and the connecting portions of each bus
bar are accommodated between the upper and lower casings and a pair of the
terminal portions are, respectively, projected symmetrically from the
terminal holes which are formed at the identical positions of the opposed
faces in the connector coupling portions.
The bus bar blank of the present invention is formed by using a single die
and each bus bar set constituted by a pair of the coupling portions, a
pair of the connecting portions and a pair of the terminal portions
extending continuously from the carrier is shaped so as to cope with a
plurality of kinds of patterns for the bus bar. Therefore, by cutting off
unnecessary portions from the bus bar set properly, bus bars of different
patterns can be obtained from the bus bar blank formed by using the
identical die. Furthermore, if the bus bar blank is cut into bus bars each
corresponding to one bus bar set or a plurality of the bus bar sets as
required, the bus bars can be used for the branch joint box in which the
connector coupling portions are provided in parallel.
Moreover, the casing of the branch joint box is formed by the upper and
lower casings of an identical shape by overturning one of the upper and
lower casings upside down and the terminal holes are formed at the
identical positions of the opposed faces of the branch joint box.
Therefore, when the coupling portions and the connecting portions of each
bus bar are disposed between the upper and lower casings and the terminal
portions extending symmetrically from the opposite connecting portions are
projected out of the terminal holes on the opposed faces of the branch
joint box, the bus bars formed from the bus bar blank can be mounted on
the branch joint box.
By the above described arrangement of the branch joint box, the opposed
faces of the branch joint box have an identical circuit, so that
directivity of the upper and lower faces of the branch joint box is
eliminated, thereby resulting in rise of working efficiency at the time of
use of the branch joint box.
Meanwhile, in order to accomplish the second object of the present
invention, a branch joint box according to the present invention
comprises: a base plate; and a pair of connector coupling portions which
are, respectively, formed on opposite faces of the base plate so as to
confront each other; the base plate being formed with a plurality of
insertion openings for inserting therethrough bus bars each including an
elongated base portion and at least one pair of tabs extending from
opposite sides of the base portion, respectively; the insertion openings
extending through the base plate so as to communicate the connector
coupling portions with each other; wherein the bus bars are secured in the
insertion openings, respectively such that the tabs project into the
connector coupling portions, respectively.
In this branch joint box, since the insertion openings extend through the
base plate so as to communicate with each other the connector coupling
portions formed on the opposite faces of the base plate, the casing of the
branch joint box is formed by a one-piece member.
Meanwhile, in the branch joint box, the bus bars may be gripped between a
retainer plate retained in one of the connector coupling portions and
partition wall portions of each insertion opening. Therefore, even if a
force for drawing the bus bars towards either one of the connector
coupling portions is applied to the bus bars, displacement of the bus bars
is prevented by the retainer plate or the partition wall portions and
thus, the bus bars are secured in the insertion openings.
Furthermore, in the branch joint box, the bus bars may be gripped between a
pair of the retainer plates. Hence, even if a force for drawing the bus
bars towards either one of the connector coupling portions is applied to
the bus bars, displacement of the bus bars is regulated by the retainer
plates and thus, the bus bars are secured in the insertion openings.
In addition, in the branch joint box, if a tab for press fitting each tab
of each bus bar into each insertion opening is provided on each insertion
opening, the bus bars are held in the insertion openings more positively.
BRIEF DESCRIPTION OF THE DRAWINGS
These objects and features of the present invention will become apparent
from the following description taken in conjunction with the preferred
embodiments thereof with reference to the accompanying drawings, in which:
FIG. 1 is a top plan view showing one example of a prior art branch joint
box (already referred to);
FIGS. 2 and 3 are schematic sectional views of the prior art branch joint
box of FIG. 1 (already referred to);
FIG. 4 is a top plan view of a bus bar blank of the present invention;
FIG. 5 is a top plan view of a bus bar member obtained by cutting the bus
bar blank of FIG. 4;
FIGS. 6, 7 and 8 are a left side elevational view, a top plan view and a
right side elevational view of a bus bar formed from the bus bar member of
FIG. 5, respectively;
FIG. 9 is a top plan view of the bus bar member of FIG. 5 having cutting
portions;
FIG. 10 is a top plan view of a bus bar member obtained by further cutting
the bus bar member of FIG. 9;
FIGS. 11, 12 and 13 are a left side elevational view, a top plan view and a
right side elevational view of a bus bar formed from the bus bar member of
FIG. 10, respectively;
FIG. 14 is a top plan view of a bus bar blank having cutting portions
different from those of FIG. 4;
FIGS. 15, 16 and 17 are a left side elevational view, a top plan view and a
right side elevational view of a bus bar formed from the bus bar blank of
FIG. 14, respectively;
FIG. 18 is a view similar to FIG. 4, particularly showing its modification;
FIG. 19 is a top plan view of a bus bar member obtained from the bus bar
blank of FIG. 18;
FIGS. 20, 21 and 22 are a left side elevational view, a top plan view and a
right side elevational view of a bus bar formed from the bus bar member of
FIG. 19, respectively;
FIG. 23 is a top plan view of a branch joint box according to a first
embodiment of the present invention;
FIG. 24 is a front elevational view of the branch joint box of FIG. 23;
FIG. 25 is a sectional view taken along the line XXV--XXV in FIG. 24, in
which the bus bars of FIG. 6 are accommodated in the branch joint box of
FIG. 23;
FIG. 26 is a front elevational view of the branch joint box of FIG. 25;
FIG. 27 is a schematic view showing arrangement of the bus bars of FIG. 11
in the branch joint box of FIG. 23;
FIG. 28 is a front elevational view of a branch joint box which is a first
modification of the branch joint box of FIG. 23;
FIG. 29 is a front elevational view of the branch joint box of FIG. 28, in
which the bus bars of FIG. 15 are accommodated;
FIG. 30 is a front elevational view of a branch joint box which is a second
modification of the branch joint box of FIG. 23;
FIG. 31 is a front elevational view of the branch joint box of FIG. 30, in
which the bus bars of FIG. 6 are accommodated;
FIG. 32 is a top plan view of a branch joint box according to a second
embodiment of the present invention;
FIG. 33 is a sectional view taken along the line XXXIII--XXXIII in FIG. 32;
FIG. 34 is a sectional view taken along the line XXXIV--XXXIV in FIG. 32;
FIG. 35 is a bottom plan view of the branch joint box of FIG. 32;
FIG. 36 is a top plan view of a casing of the branch joint box of FIG. 32;
FIG. 37 is a sectional view taken along the line XXXVII--XXXVII in FIG. 36;
FIG. 38 is a sectional view taken along the line XXXVIII--XXXVIII in FIG.
36;
FIG. 39 is an enlarged view showing an insertion opening formed in the
casing of FIG. 36;
FIG. 40 is an enlarged sectional view taken along the line XL--XL in FIG.
36;
FIG. 41 is a front elevational view of a bus bar blank for obtaining bus
bars for the branch joint box of FIG. 32;
FIG. 42 is a side elevational view of the bus bar blank of FIG. 41;
FIG. 43 is a front elevational view of the bus bars obtained from the bus
bar blank of FIG. 41;
FIG. 44 is a front elevational view of a first retainer plate employed in
the branch joint box of FIG. 32;
FIG. 45 is a side elevational view of the first retainer plate of FIG. 44;
FIG. 46 is a front elevational view of a second retainer plate employed in
the branch joint box of FIG. 32;
FIG. 47 is a side elevational view of the second retainer plate of FIG. 46;
FIG. 48 is a sectional view of a branch joint box which is a modification
of the branch joint box of FIG. 32;
FIG. 49 is a top plan view of a casing of the branch joint box of FIG. 48;
FIG. 50 is a sectional view taken along the line L--L in FIG. 49;
FIG. 51 is a view similar to FIG. 41, particularly showing its first
modification; and
FIG. 52 is a view similar to FIG. 41, particularly showing its second
modification.
Before the description of the present invention proceeds, it is to be noted
that like parts are designated by like reference numerals throughout
several views of the accompanying drawings.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, there is shown in FIG. 4, a bus bar blank B
of the present invention. The bus bar blank B includes an elongated
carrier 1 and a plurality of pairs of coupling portions 2 extending
orthogonally from opposite sides of the carrier 1, respectively at a
predetermined interval L1 in a longitudinal direction of the carrier 1. A
connecting portion 3 having a predetermined length is provided at a distal
end of each of the coupling portions 2 so as to extend in parallel with
the carrier 1. A pair of first terminal portions 4 extend orthogonally
(perpendicularly) from the opposite connecting portions 3, respectively,
while a pair of second terminal portions 5 extend orthogonally from the
opposite connecting portions 3, respectively. The first and second
terminal portions 4 and 5 interpose a center 0 of the coupling portion 2
therebetween so as to be spaced a distance L2 from the center O,
respectively. Meanwhile, a pair of third terminal portions 6 extend
orthogonally from the opposite connecting portions 3, respectively. The
third terminal portion 6 is spaced a distance L3 from the first terminal
portion 4 at one side of the first terminal portion 4 remote from the
second terminal portion 5 such that the first terminal portion 4 is
interposed between the second and third terminal portions 5 and 6. The
first, second and third terminal portions 4, 5 and 6 have an identical
shape in length and width. The third terminal portion 6 is disposed at one
side of the first terminal portion 4 remote from the second terminal
portion 5 as described above but may also be disposed at one side of the
second terminal portion 5 remote from the first terminal portion 4.
At a base portion of each of the first and second terminal portions 4 and
5, a notch 7 for facilitating bending of the base portion of each of the
first and second terminal portions 4 and 5 is formed on the connecting
portion 3. A pair of the coupling portions 2, a pair of the connecting
portions 3 and a pair of the first, second and third terminal portions 4,
5 and 6, which are formed as one bus bar set symmetrically with respect to
the carrier 1, are successively arranged at the predetermined interval L1
in the longitudinal direction of the carrier 1. A gap S is defined between
the second and third terminal portions 5 and 6 of two neighboring bus bar
sets. Namely, as shown in FIG. 4, the gap S is defined between the third
terminal portion 6 of a first bus bar set S1 and the second terminal
portion 5 of a second bus bar set S2.
According to constructions of a branch joint box 10 (FIG. 23) to which bus
bars formed from the bus bar blank B are attached, one bus bar set can be
separated from the bus bar blank B each time by cutting time carrier 1 as
shown in FIG. 4 or a plurality of bus bar sets can be separated from the
bus bar blank B each time by cutting the carrier 4 as shown in FIG. 14. In
case one bus bar set is cut from the bus bar blank B each time, the
carrier 1 is cut along cutting lines l1 in FIG. 4 and thus, a bus bar
member 8A is obtained as shown in FIG. 5. Then, by using the notches 7 of
the bus bar member 8A as starting points, the bus bar member 8A is bent
through 90.degree. in an identical direction along bending lines l2 in
FIG. 5. As a result, a bus bar 9A in which the first and third terminal
portions 4 and 6 extend in an identical plane and the first and second
terminal portions 4 and 5 confront each other is obtained as shown in
FIGS. 6 to 8. In FIGS. 6 to 8, "P1" denotes a pitch between the first and
second terminal portions 4 and 5, while "P2" denotes a pitch (distance L3)
between the first and third terminal portions 4 and 6 in a direction
orthogonal to that of the pitch P1.
Meanwhile, when the bus bar member 8A obtained by cutting the carrier 1 of
the bus bar blank B as shown in FIG. 4 is further cut along cutting lines
l3 in FIG. 9 so as to cut off the third terminal portions 6 from the bus
bar member 8A and thus, a bus bar member 8B is obtained as shown in FIG.
10. Then, when the bus bar member 8B is bent along bending lines l2 and
thus, a bus bar 9B is obtained as shown in FIGS. 11 to 13. In the bus bar
9B, since the third terminal portions 6 are eliminated from the bus bar
9B, the first and second terminal portions 4 and 5 confront each other.
In case a plurality of bus bar sets are cut from the bus bar blank B each
time, two bus bar sets are cut from the bus bar blank B each time by
cutting the carrier 1 along cutting lines l4 as shown in FIG. 14. In
addition, the connecting portions 3 are cut along cutting lines l5 so as
to cut off the third terminal portions 6 from the connecting portions 3.
Subsequently, the connecting portions 3 are bent through 90.degree. along
bending lines l2. As a result, a bus bar 9C is obtained as shown in FIGS.
15 to 17.
By cutting predetermined portions of the carrier 1 and the connecting
portions 3 if necessary and by bending the bus bar blank B through
90.degree. along the bending lines l2, bus bars 9 including the bus bars
9A, 9B, 9C, etc. of a plurality of patterns necessary for the branch joint
box 10 for effecting branch joint of wiring harnesses can be formed from
the bus bar blank B. Since the bus bars 9A, 9B, 9C, etc. of a plurality of
patterns can be formed from the single bus bar blank B, the number of
kinds of dies for 10 molding the bus bar blanks can be reduced to one and
thus, production cost of the bus bars can be lowered.
Meanwhile, the bus bar blank B is not restricted to the above described
shape but may be modified as shown in FIG. 18. In a modified bus bar blank
B' shown in FIG. 18, a further third terminal portion 6' is additionally
provided at one side of the second terminal portion 5 remote from the
first terminal portion 4 so as to be spaced the distance L3 from the
second terminal portion 5. By cutting the bus bar blank B', a bus bar
member 8D of one bus bar set, for example, is formed as shown in FIG. 19.
Then, by bending the bus bar member 8D, a bus bar 9D is obtained as shown
in FIGS. 20 to 22. In the bus bar 9D, a pitch between the third and
further third terminal portions 6 and 6' is equal to the pitch P1 between
the first and second terminal portions 4 and 5, while a pitch between the
second and further third terminal portions 5 and 6' is equal to the pitch
P2 between the first and third terminal portions 4 and 6. In the same
manner as the bus bar blank B, the bus bars 9 of a plurality of patterns
can be formed also from the bus bar blank B'.
FIGS. 23 and 24 show a branch joint box 10 for accommodating the bus bars
9, according to a first embodiment of the present invention. A casing 11
of the branch joint box 10 is formed by upper and lower casings 11A and
11B of identical rectangular shape coupled with each other by overturning
one of the upper and lower casings 11A and 11B upside down. A locking
portion 11b and a mating locking portion 11c engageable with the locking
portion 11b are provided on each of opposite outer side faces of the upper
and lower casings 11A and 11B in the vicinity of one end face 11a of each
of the upper and lower casings 11A and 11B. Each of the upper and lower
casings 11A and 11B has a bracket 11dfor securing the casing 11 to a
mounting panel (not shown) of a motor vehicle.
Each of the upper and lower casings 11A and 11B has open opposite ends. At
one end face 11a, the upper and lower casings 11A and 11B are coupled with
each other and a bus bar mounting portion 12 in which the bus bars 9 are
arranged is provided. At the other end face 11e, a connector coupling
portion 13 for receiving a connector (not shown) so as to connect the
connector to the bus bars 9 is provided. The bus bar mounting portion 12
and the connector coupling portion 13 are separated from each other by a
partition wall 11f. The partition wall 11f acts as an end face of the
connector coupling portion 13, on which two rows of terminal holes 11g for
inserting therethrough the terminal portions 4, 5 and 6 of the bus bars 9
are formed as shown in FIG. 24 so as to be spaced a predetermined distance
from each other. In FIG. 24, a lateral distance between the two rows of
the terminal holes 11g is set to the pitch P1 between the first and second
terminal portions 4 and 5 and a vertical distance between neighboring ones
of the terminal holes 11g is set to the pitch P2 between the first and
third terminal portions 4 and 6.
The bus bars 9 of an identical pattern formed from the bus bar blank B or
B' are adapted to mounted on the branch joint box 10 of the above
described arrangement. For example, the bus bars 9A shown in FIGS. 6 to 8
are accommodated in the branch joint box 10 as shown in FIGS. 25 and 26 so
as to form a branch circuit. Meanwhile, it is needless to say that the bus
bars of another pattern or the bus bars of a plurality of patterns may be
used for the branch joint box 10. However, it is preferable that the bus
bars of one pattern are used for the single branch joint box 10.
The bus bars 9 are mounted on the branch joint box 10 as follows.
Initially, one bus bar 9A is disposed in the vicinity of the bus bar
mounting portion 12 of the upper casing 11A and the first, second and
third terminal portions 4, 5 and 6 located at one side X of the bus bar 9A
are inserted through the terminal holes 11g of the upper casing 11A so as
to be projected into the connector coupling portion 13 of the upper casing
11A. Subsequently, a bus bar 9A' identical with the bus bar 9A except for
positions of the first, second and third terminal portions 4, 5 and 6 is
provided such that the first and second terminal portions 4 and 5 of the
bus bar 9A' confront the second and first terminal portions 5 and 4 of the
bus bar 9A mounted already on the branch joint box 10, respectively. Thus,
the first and second terminal portions 4 and 5 of the bus bar 9A' are
inserted through the terminal holes 11g. By repeating such procedures, the
first, second and third terminal portions 4, 5 and 6 of the bus bars 9 are
inserted through all the terminal holes 11g.
Thereafter, the first, second and third terminal portions 4, 5 and 6
located at the other side Y of the bus bars 9A and projecting out of the
bus bar mounting portion 12 of the upper casing 11A are inserted through
the terminal holes 11g of the lower casing 11B so as to be protruded into
the connector coupling portion 13 of the lower casing 11B. Finally, the
locking portions 11b and the mating locking portions 11c of the lower
casing 11B are, respectively, brought into engagement with the mating
locking portions 11c and the locking portions 11b of the upper casing 11A
such that the branch joint box 10 is assembled in a state where the
carriers 1 of the bus bars 9A and 9A' are accommodated in the bus bar
mounting portions 12. Connectors (not shown) are coupled with the
connector coupling portions 13 disposed at opposite sides of the branch
joint box 10, respectively. Meanwhile, the bus bars 9B shown in FIGS. 11
to 13 can be mounted on the branch joint box 10 as shown in FIG. 27.
As described above, in the branch joint box 10, a branch circuit can be
formed by using the bus bars 9 of an identical pattern. Therefore, since
additional time is not wasted for selecting the bus bars 9, efficiency for
assembling the branch joint box 10 can be raised. Meanwhile, since the
branch joint box 10 obtained by coupling the upper and lower casings 11A
and 11B of an identical shape with each other, circuit patterns on the
opposite faces of the branch joint box 10 can be made coincident with each
other. Accordingly, directivity of the upper and lower faces of the branch
joint box 10 can be eliminated, thus resulting in further rise of
efficiency for assembling the branch joint box 10.
Meanwhile, FIGS. 28 and 29 show a branch joint box 10' which is a first
modification of the branch joint box 10. In the branch joint box 10', a
plurality of, for example, two sets of the connector coupling portions 13
each having two rows of the terminal holes 11g are provided side by side
such that a plurality of connectors (not shown) can be coupled with the
branch joint box 10'. A distance between the two connector coupling
portions 13 is set to the interval L1 between the centers O of neighboring
ones of the coupling portions 2 of the bus bar blank B. In the branch
joint box 10', a branch circuit can be formed by using the bus bars 9C
each having two sets of the first and second terminal portions 4 and 5 at
its one side as shown in FIG. 29.
FIGS. 30 and 31 show a branch joint box 10" which is a second modification
of the branch joint box 10. Since two connectors having different outer
shapes are coupled with the branch joint box 10", connector coupling
portions 13 and 13' different in size from each other are juxtaposed in
the branch joint box 10". As shown in FIGS. 31, a branch circuit can be
formed in the branch joint box 10" by using, for example, the bus bars 9A
shown in FIGS. 6 to 8.
As is clear from the foregoing of the bus bar blank of the present
invention, a plurality of pairs of the coupling portions extend from the
opposite sides of the carrier, respectively at the predetermined .interval
in the longitudinal direction of the carrier, while the first and second
terminal portions are symmetrically projected from each of the coupling
portions through the connecting portions. In addition, the third terminal
portion is provided at an outside of the first or second terminal portion
or at opposite sides of the first and second terminal portions. By cutting
the carrier and the coupling portions at the predetermined positions and
bending the base portions of the first and second terminal portions, the
bus bars of a plurality of patterns can be formed. When the bus bars of a
plurality of patterns are formed, the number of kinds of dies for molding
the bus bar blanks can be reduced to one, thereby resulting in great
reduction of production cost of the bus bar blank.
Meanwhile, in the branch joint box in which the bus bars formed from the
above mentioned bus bar blank, since the distance between the two rows of
the terminal holes for inserting the terminal portions therethrough is set
to the pitch between the first and second terminal portions and the
distance between neighboring ones of the terminal holes in each row of the
terminal holes is set to the pitch between the first and third terminal
portions, the two rows of the terminal holes are disposed symmetrically
with respect to a centerline L (FIG. 24) of the branch joint box
perpendicular to the rows of the terminal holes, a branch circuit can be
formed by the bus bars of one pattern. Therefore, since additional time is
not wasted for selecting the bus bars, efficiency for assembling the
branch joint box can be raised.
Meanwhile, since the branch joint box is formed by the upper and lower
casings of an identical shape such that the bus bars of one pattern can be
mounted on the branch joint box, branch circuits formed on the opposite
sides of the branch joint box are identical with each other. As a result,
since directivity of the upper and lower faces of the branch joint box is
eliminated, efficiency for assembling the branch joint box can be further
raised.
FIGS. 32 to 3S show a branch joint box 60 according to a second embodiment
of the present invention. In the branch joint box 60, bus bars 32 shown in
FIGS. 41 to 43 are accommodated in a resinous casing 31 shown in FIGS. 36
to 40 and are retained by first and second retainer plates 33 and 34 shown
in FIGS. 44 and 4B and FIGS. 46 and 47, respectively. As shown in FIGS. 32
to 38, the casing 31 includes a rectangular thick base plate 36. Connector
connecting portions 38A and 39A each having a tubular peripheral wall 37
are projected from an upper face 36a of the base plate 36, while connector
coupling portions 38B and 39B each having the peripheral wall 37 are
likewise projected from a lower face 36b of the base plate 36. The
connector coupling portions 38A and 38B receive connectors X of an
identical shape and are provided at symmetrical positions on the upper and
lower faces 36a and 36b of the base plate 36, respectively so as to
confront each other. Similarly, the connector coupling portions 39A and
39B receive connectors Y of an identical shape and are provided at
symmetrical positions on the upper and lower faces 36a and 36b of the base
plate 36, respectively so as to confront each other.
At the connector coupling portions 38A, 38B, 39A and 39B, insertion
openings 41a to 41n each having a shape of an elongated slot are passed
through the base plate 36 from the upper face 36a to the lower face 36b so
as to communicate the connector coupling portions 38A and 39A with the
connector coupling portions 38B and 39B, resp | | |
