U.S. patent application number 09/903653 was filed with the patent office on 2002-01-17 for resin shield circuit device.
Invention is credited to Irie, Hitoshi, Yamamoto, Naoki.
Application Number | 20020006749 09/903653 |
Document ID | / |
Family ID | 18708902 |
Filed Date | 2002-01-17 |
United States Patent
Application |
20020006749 |
Kind Code |
A1 |
Yamamoto, Naoki ; et
al. |
January 17, 2002 |
Resin shield circuit device
Abstract
In the resin shield circuit device, a resin case is provided
with a recess having an opening. Each end of connector terminals is
exposed out of the resin case and the other end thereof is embedded
into the resin case. Base portions of wiring metal pieces are
embedded into the resin case and connected in circuit with the
other ends of the connector terminals. Connecting portions of the
wiring metal pieces protrude into the recess. Lead terminals of
circuit elements are connected and fixed to the connecting
portions, respectively. A resin shield portion filled in the recess
covers the circuit elements and the connecting portions of the
wiring metal pieces in such a manner that only a flat surface of
the resin shield portion is exposed out of the opening of the
recess to outside.
Inventors: |
Yamamoto, Naoki; (Chita-gun,
JP) ; Irie, Hitoshi; (Nagoya-city, JP) |
Correspondence
Address: |
Pillsbury Winthrop LLP
1600 Tysons Boulevard
McLean
VA
22102
US
|
Family ID: |
18708902 |
Appl. No.: |
09/903653 |
Filed: |
July 13, 2001 |
Current U.S.
Class: |
439/620.21 |
Current CPC
Class: |
H05K 3/202 20130101;
Y10S 439/936 20130101; H01R 13/66 20130101; H01R 43/24 20130101;
H05K 3/284 20130101 |
Class at
Publication: |
439/620 |
International
Class: |
H01R 013/66 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 13, 2000 |
JP |
2000-213086 |
Claims
What is claimed is:
1. A resin shield circuit device comprising: a resin case being
provided with a recess having an opening; connector terminals whose
each end is exposed out of the resin case and whose each another
end is embedded into and fixed to the resin case; a plurality of
wiring metal pieces each having a base portion and a connecting
portion, the base portion being embedded into and fixed to the
resin case and connected in circuit with the another end of the
connector terminal inside the resin case and the connecting portion
protruding into the recess; a plurality of circuit elements each
having a main body and lead terminals, any of the lead terminals
being connected and fixed to any of the connecting portions; and a
resin shield portion filled in the recess to cover the main bodies,
the lead terminals and the connecting portions, the resin shield
portion having a flat surface exposed out of only the opening to
outside.
2. A resin shield circuit device according to claim 1, wherein all
of the lead terminals are connected inside the resin shield portion
to the wiring metal pieces and not exposed out of the flat surface
of the resin shield portion.
3. A resin shield circuit device according to claim 1, wherein the
circuit elements and the wiring metal pieces are arranged not to
overlap each other in a direction perpendicular to the flat surface
of the resin shield portion.
4. A resin shield circuit device according to claim 3, wherein the
connecting portions extend in the recess in parallel to the flat
surface of the resin shield portion.
5. A resin shield circuit device according to claim 4, wherein the
connecting portions extend in the recess on a single hypothetical
surf ace parallel to the flat surface of the resin shield
portion.
6. A resin shield circuit device according to claim 3, further
comprising: a shelf formed integrally with the resin case in a
shape of protruding inward out of an inner surface of the recess so
that any of the main bodies and lead terminals of the circuit
elements is mounted on the shelf at a given distance from the flat
surface of the resin shield portion.
7. A resin shield circuit device according to claim 3, wherein any
of the connecting portions is provided with a depression serving to
restrict a movement of the lead terminal mounted thereon.
8. A resin shield circuit device according to claim 6, wherein the
shelf is provided with a depression serving to restrict a movement
of said at least one of the main body and lead terminals of the
circuit element that is mounted thereon.
9. A resin shield circuit device according to claim 1, further
comprising: another recess formed in the resin case, the another
recess having another opening that is opened in a direction
different from that of the opening of the recess; a plurality of
another wiring metal pieces each having another base portion and
another connecting portion, the another base portion being embedded
into and fixed to the resin case and connected in circuit with the
another end of the connector terminal and the another connecting
portion protruding into the another recess; another circuit element
having another main body and another lead terminals, any of the
anther lead terminals being connected and fixed to any of the
another connecting portions; and another resin shield portion
filled in the another recess to cover the another main body and
lead terminals and the another connecting portions, the another
resin shield portion having another flat surface exposed out of
only the another opening to outside.
10. A resin shield circuit device according to claim 1, wherein the
resin case is provided with a connector recess, into which the ends
of the connector terminals protrude.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of
priority of Japanese Patent Application No. 2000-213086 filed on
Jul. 13, 2000, the content of which is incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a resin shield circuit
device.
[0004] 2. Description of Related Art
[0005] Conventionally, a resin shield circuit device is formed by
accommodating a circuit board (a printed wiring board), on which
circuit elements are mounted and which has connecting terminals
leading to outside, into a recess of a resin case and, after
pouring liquid resin from an opening of the recess into inside of
the recess by potting, hardening the liquid resin. This is
hereinafter called a potting type resin shield circuit device.
[0006] Further, a conventional resin mold semiconductor device is
formed by bonding semiconductor chips on metal bases stamped
together with lead frames, connecting respective wiring metal
regions of the semiconductor chips to the respective lead frames by
wire bonding or in use of balls or pumps, then, shielding the
connecting portions and the semiconductor chips by resin molding
and, finally, cutting off junctions connecting the respective lead
frames. This is hereinafter called molding type resin shield
circuit device.
[0007] Furthermore, a conventional resin connector has a connecting
terminal protruding into a recess of a connector body for coupling
with an opponent plug. A base of the connecting terminal is fixed
to the connector body by insert molding. Moreover, a resin shield
circuit device, in which the resin connecter mentioned above and
the potting type resin shield circuit device are integrated into
one body, is also known.
[0008] The potting type resin shield circuit device has good
characteristics such as exclusion of moisture and improved
reliability since the resin filled in the recess of the resin case
is exposed to outside only from the opening of the recess, but has
problems to solve as described below.
[0009] When many of the circuit elements (discreet circuit
elements) having lead terminals and many wiring metal pieces are
mounted on the printed wiring board, it becomes necessary to cut in
advance respective lengths of the lead terminals and connecting
portions of the wiring metal pieces to respective predetermined
values before inserting the lead terminals and the wiring metal
pieces into apertures of the printed wiring board for soldering.
Further, it becomes necessary to form wiring patterns on the
printed wiring board. Accordingly, manufacturing processes of the
circuit device are complicated and much more material is used.
[0010] Further, when the circuit element rises for a certain
distance out of a flat surface of the printed wiring board, it is
necessary that the circuit device has thickness corresponding to at
least a sum of length of each of the lead terminals and height of
the circuit element. As a result, a more amount of resin for
shielding and a larger body of the circuit device are required.
Furthermore, in a case of the circuit element having lead terminals
that extend in opposite directions from the ends thereof, the lead
terminal on a side opposite to the printed wiring board is required
to bend by 180 degrees angle. When the circuit element lies on the
printed wiring board, the lead terminals are required to bend at
approximately right angles so that the manufacturing process is
complicated.
[0011] Moreover, outside connecting terminals, which connect the
wiring patterns of the printed wiring board to outside, protrude
out of a resin shield portion. Since heat stress occurs between the
outside connecting terminals and the resin shield portion whose
heat expansion rates are different, a crack or a small gap, through
which moisture is entered into inside of the circuit device, is
likely formed at a boundary between contacts of the outside
connecting terminals and the resin shield portion, during a long
time when the circuit device is used.
SUMMARY OF THE INVENTION
[0012] An object of the invention is to provide a compact and
reliable resin shield circuit device that is manufactured at
simpler manufacturing processes and with less amount of material to
be used.
[0013] To achieve the above objects, in the resin shield circuit
device, a resin case is provided with a recess having an opening.
Each end of connector terminals is exposed out of the resin case
and the other end thereof is embedded into and fixed to the resin
case. Base portions of wiring metal pieces are embedded into and
fixed to the resin case and connected in circuit with the other
ends of the connector terminals. Connecting portions of the wiring
metal pieces protrude into the recess. Respective lead terminals of
circuit elements are connected and fixed to the respective
connecting portions. A resin shield portion filled in the recess
covers the circuit elements and the connecting portions of the
wiring metal pieces in such a manner that only a flat surface of
the resin shield portion is exposed out of the opening of the
recess to outside.
[0014] According to the resin shield circuit device mentioned
above, the resin shield portion is formed generally by potting
process and has the flat surface exposed only out of the opening of
the recess to outside, resulting in good characteristics of
moisture exclusion and reliability, similarly to the conventional
potting type resin shield circuit device.
[0015] Further, each of the circuit elements is directly mounted on
and fixed to each of the wiring metal pieces without using the
conventional printed wiring board to be housed in the recess of the
resin case so that a volume of the recess is smaller and the
manufacturing processes is simpler. It is not necessary to connect
a wiring of the printed wiring board to the wiring metal
pieces.
[0016] Furthermore, since the wiring metal pieces are formed
together with the resin case by insert molding, the manufacturing
process is simpler.
[0017] When the circuit elements are mounted on the printed wiring
board, it is very common that main bodies of the circuit elements
are positioned at certain distances from a surface of the printed
wiring to secure faster flow of potting resin and not to make voids
of resin. Accordingly, the amount of resin for shielding of the
conventional device is larger, compared with the resin amount of
the resin shield portion of the circuit device, in which the lead
terminals of the circuit elements are directly fixed to the wiring
metal pieces so that idling space in the recess is reduced.
[0018] It is preferable that all of the lead terminals are
connected inside the resin shield portion to the wiring metal
pieces and not exposed out of the flat surface of the resin shield
portion. Since the lead terminals of the circuit elements are
connected in circuit to outside only through the wiring metal
pieces and the connector terminals, there is no risk that moisture
enters through gaps between the lead terminals and the resin shield
portion that is formed by relatively low density resin, as is the
conventional potting type resin shield circuit device. Accordingly,
reliability of excluding moisture and hydrolysis due to the
moisture is remarkably improved.
[0019] Further, preferably, the circuit elements and the wiring
metal pieces are arranged not to overlap each other in a direction
perpendicular to the flat surface of the resin shield portion. with
this arrangement, mounting of the circuit elements on the wiring
metal pieces in the recess becomes very easy since the circuit
elements can be inserted into the recess and soldered to the wiring
metal pieces in a depth direction of the recess without interfering
with each other.
[0020] Further, it is preferable that the connecting portions
extend in the recess in parallel to the flat surface of the resin
shield portion. More preferably, the connecting portions extend in
the recess on a single hypothetical surface parallel to the flat
surface of the resin shield portion. With these constructions,
manufacturing processes including setting the wiring metal pieces
in an insert molding die and mounting the circuit elements on the
wiring metal pieces become simpler and easier.
[0021] Furthermore, it is preferable to have a shelf formed
integrally with the resin case in a shape of protruding inward out
of an inner surface of the recess so that any of the main bodies or
lead terminals of the circuit elements is easily mounted on the
shelf at a given distance from the flat surface of the resin shield
portion.
[0022] To secure an adequate positioning of the main body or lead
terminal of the circuit element when the circuit element is mounted
on the wiring metal piece, it is preferable that the shelf or the
connecting portion of the wiring metal piece is provided with a
depression.
BRIEF DESCRIPTION OF THE DRAWING
[0023] Other features and advantages of the present invention will
be appreciated, as well as methods of operation and the function of
the related parts, from a study of the following detailed
description, the appended claims, and the drawings, all of which
form a part of this application. In the drawings:
[0024] FIG. 1 is a plan view of a circuit device according to a
preferred embodiment (a resin shield portion omitted);
[0025] FIG. 2 is a cross sectional view taken along a line H-H of
FIG. 1; and
[0026] FIG. 3 is a partly enlarged cross sectional view taken along
a line III-III of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] A potting type resin shield circuit device according to a
preferred embodiment of the present invention is described with
reference with FIGS. 1 to 3.
[0028] The potting type resin shield circuit device is a voltage
regulator with a connector. A resin circuit case 1 has a main body
1c and a connector body 1d formed integrally with the main body 1c.
The main body 1c is provided with first and second recesses 1a and
1b which are opened in opposite directions and in which circuit
elements are accommodated.
[0029] An IC module 2 is one of the circuit elements in which a
regulator IC chip (not shown) is housed in a resin molding package.
Circuit elements 3 to 5 are outside mounting circuit elements for
the IC module 2. The IC module 2 and the circuit 3 to 5 constitute
the voltage control regulator installed in a known alternator for
vehicles.
[0030] Wiring metal pieces 6 to 11 are fixed to the circuit case 1
and protrude out of a side wall 100a surrounding the first recess
1a toward an inside of the first recess 1a. Each of the wiring
metal pieces 6 to 11 is composed of a base portion embedded into
the circuit case 1 (FIG. 2 shows only a part of the base 71 of the
wiring metal piece 7) and a lead terminal connecting portion
protruding into the inside of the first recess 1a in parallel to a
bottom surface 100b (or an opening surface thereof) of the first
recess 1a at a mutually identical interval from the bottom surface
100b. Lead terminals 12 and 13 of the circuit element 3, lead
terminals 14 and 15 of the circuit element 4 and lead terminals 16
and 17 of the circuit element 5 are separately mounted on and
soldered to the respective lead terminal connecting portions of the
wiring metal pieces 6 to 11.
[0031] A shelf 18 is formed integrally with the circuit case 1 and
rises out of the bottom 100b to constitute a resin pedestal. A body
(other than the lead terminals 16 and 17) of the circuit element 5
is mounted on the shelf 18. The shelf 18 is not always necessary
for mounting the lead terminals 16 and 17 on the wiring metal
pieces 10 and 11 and whether the shelf 18 is provided or not
depends on a shape of the circuit element 5. Further, a shelf or
pedestal similar to the shelf 18 may be provided for mounting a
body of the other circuit element 3 or 4. A resin shield portion 19
is formed in such a manner that epoxy resin is poured into the
first recess 1a by potting after the lead terminals 16 to 17 are
mounted on the wiring metal pieces 6 to 11, respectively.
[0032] Wiring metal pieces 20 to 22 are fixed to the circuit case 1
and protrude out of a side wall 200a surrounding the second recess
1b toward an inside of the second recess 1b. Each of the wiring
metal pieces 20 to 22 is composed of a base portion embedded into
the circuit case 1 and a lead terminal connecting portion
protruding into the inside of the second recess lab in parallel to
a bottom surface 200b of the second recess 1b (or an opening
surface thereof) at a mutually identical interval from the bottom
surface 200b. Lead terminals 23 to 25 of the IC module 2 are
separately mounted on and soldered to the respective lead terminal
connecting portions of the wiring metal pieces 20 to 22.
[0033] A shelf 26 is formed integrally with the circuit case 1 and
rises out of the bottom 200b to constitute a resin pedestal. A body
(other than the lead terminals 23 to 25) of the IC module 2 is
mounted on the shelf 26. A resin shield portion 27 is formed in
such a manner that epoxy resin is poured into the second recess 1b
by potting.
[0034] Connector terminals 28 and 29 protrude into a connector
recess 1e provided in the connector body 1d. The connector
terminals 28 and 29 are inserted into holes of a plug (not shown)
that is detachably fitted to the recess 1e and connected
electrically to female terminals provided in the holes of the plug.
The connector terminals 28 and 29 are connected in circuit with the
wiring metal pieces 12 to 17 inside the circuit case.
[0035] A manufacturing method of the resin shield circuit device
according to the preferred embodiment is described below.
[0036] The circuit case 1 having the wiring metal pieces 6 to 11,
and 20 to 22, the connector terminals 28 and 28 is formed by resin
insert molding. Then, the circuit elements 3 to 5 are inserted into
the first recess 1a from the opening thereof to position at given
places in the first recess 1a and the read terminals 12 to 17 are
soldered to the wiring metal pieces 6 to 11 from a side of the
opening of the first recess 1a. Any of the wiring metal pieces 6 to
11 may have a depression for easily mounting or positioning any of
the read terminals 12 to 17, as shown in FIG. 3 as an example of
the wiring metal piece 11 and the read terminal 17. Further, the
shelf 18 may be provided with a depression for easily mounting or
positioning any of the bodied or lead terminals of the circuit
element 3 to 5.
[0037] Further, solder may be put or coated in advance on the
respective wiring metal pieces 6 to 11 and be melted after mounting
the respective read terminals 12 to 17 thereon. Moreover, to
prevent each deformation of the read terminal connecting portions
of the wiring metal pieces 6 to 11, the recess 1a may be provided
with a shelf (pedestal) rising from the bottom 100b so that each
back surface of the read terminal connecting portions of the wiring
metal pieces 6 to 11 comes in contact with a top surface of the
shelf. After the soldering process, liquid epoxy resin is poured
into the recess 1a until the epoxy resin completely covers the
circuit elements 3 to 5 and is hardened to form the resin shield
portion 19. With respect to the second recess 1b, the IC module 2
is mounted on the wiring metal pieces 20 to 22 under similar
manufacturing processes mentioned above.
[0038] The embodiment mentioned above has many advantages. The
resin shield circuit device has a good characteristic of excluding
moisture and a good reliability, since any terminal does not
penetrate the resin shield portion 19 or 27 so as to be exposed to
outside. Further, since the circuit elements 3 to 5 or the IC
module 2 are fixed to wiring metal pieces 6 to 11 or 20 to 22, that
are fixed to the circuit case 1 and protrude into the recess 1a or
1b, the conventional printed wiring board, on which the circuit
elements 3 to 5 or the IC module 2 are mounted in advance, is not
necessary so that the recess 1a or 1b is more compact. Furthermore,
as the wiring metal pieces 6 to 11, or 20 to 22 are fixed to the
circuit case 1 by well known insert molding process and the resin
shield portion 19 or 27 is formed by simple potting process, the
manufacturing processes becomes simpler. Moreover, as the circuit
elements 3 to 5 or the IC module 2 and the read terminals thereof
12 to 17 or 23 to 25 are arranged not to overlap with each other in
a direction of the opening surface of the resin shield portion 19
or 27 so that inserting, mounting and soldering processes of the
circuit elements or the IC module are easier and a flow of the
epoxy resin is smoother not to form voids.
* * * * *