CA2050851A1 - Molded plastic casing with electromagnetic shielding structure - Google Patents
Molded plastic casing with electromagnetic shielding structureInfo
- Publication number
- CA2050851A1 CA2050851A1 CA 2050851 CA2050851A CA2050851A1 CA 2050851 A1 CA2050851 A1 CA 2050851A1 CA 2050851 CA2050851 CA 2050851 CA 2050851 A CA2050851 A CA 2050851A CA 2050851 A1 CA2050851 A1 CA 2050851A1
- Authority
- CA
- Canada
- Prior art keywords
- casing
- circuit board
- printed circuit
- molded plastic
- metal core
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
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- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
- Casings For Electric Apparatus (AREA)
Abstract
Abstract of the Disclosure A molded plastic casing having an electromagnetic shielding structure. A metal film is formed on an inner face of the casing, and a printed circuit board having a metal core embedded therein is accommodated in the inside of the casing in such a manner as to divide the inside of the casing into two chambers. A plurality of plated through-holes are formed in the printed circuit board, and high frequency functioning circuits are mounted on the opposite faces of the printed circuit board. A plurality of metal lands are formed on the opposite faces of a peripheral portion of the printed circuit board and individually connected to the metal core by way of the plated through-holes. A plurality of U-shaped springs each having a plurality of tongues formed integrally thereon are mounted at the peripheral portion of the printed circuit board in individual contact with the metal lands such that the tongues thereof are held in resilient contact with the metal film.
Description
jV ~ 3 MOLDED PLASTIC CASING WITH `~
ELECTROMAGNETIC SHIELDING STRUCTURE
Field of the Invention This invention relates to a shielding structure for a molded plastic casin~ with a high frequency -functioning circuit built therein.
Background of the Invention An ultimate object of communications is ~ ;
naturally to immediately transmit or exchange a will or information from any place to any person at any time, and moblle communications have been and are being developed gradually in addltion to conventional communlcations between flxed points. Moblle communications include communications be-tween a mobile body such as a ship, an automobile or an aircraft and a general subscriber's statlon, an offlce or the like and communications between mobile bodies, and automobile telephones, portable telephones, cordless telephones are included in such mobile communications.
Among ~uch mobile communlcatlons, wlreless apparatus such as portable telephones or -the like ~ ;
require use of a thin caslng due to a demand for , - . :"
:- . ; :~
reduction in size and weight, and electronic par-ts moun-ted in a high density are accommodated in such casing. Since a high frequency band of 800 to 900 MHz called quasl-microwave band is utilized for such radio equipment, it is required to strengthen electromagnetic shielding of the inside of a casing while reducing the weight of -the casing to prevent various possible impediments which may arise from electromagnetic interference.
10In a conventional construction wherein -the inside of a molded plastic casing such as a casing of a portable telephone set is divided in-to two sections by a printed circult board, U-shaped springs are soldered to ground patterns of the printed clrcuit board while a metal film is formed by platlng, elec-trostatlc painting, vapor deposition of aluminum or the like on an inner face of the molded plastic caslng having ribs, and the U-shaped springs are angaged wlth the rlbs to establish contact therebetween.
With such conven-tional electromagnetic shielding structure, however, since U-shaped springs are soldered to a printed circuit board, there is a problem that many ~ .
steps are required for mounting of such springs.
Besides, as reduction in size and weight of a radio 2 ~;., .
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appara-tus of a portable telephone set or the like proceeds, electronic parts must necessarily be mounted in a high density on a princed circuit board, and such conventional electromagnetic shielding structure cannot cope with such high densi-ty mounting of electronic parts.
Summary of the Invention Aceordingly, lt is an obJect of the present invention to provide an eleetromagnetie shielding strueture for a molded plastic easing by whieh the inside of the easing in whieh a high frequeney funetioning elreuit ls aecommodated can be eleetromagnetleally shlelded wlth a simple structure.
In aeeordanea with an aspeet of the present invention, there is provided a molded plastie casing, eomprising: a metal film formed on an inner ~aee of the casing: a prlnted eireuit board aeeommodated in the inside of the easing in sueh a manner as to divide the inside of the easing into two chambers, the printed eireuit board having a metal eore embedded therein and having a plurallty of plated through-holes formed therein, the printed eireuit board having hiBh frequeney ~ .
functioning clrcuits mounted on the opposite faces ,, . ' ~ ' ~ ' : ' ' ; - :
;
:
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-thereof; a plurality of metal lands formed on the opposite faces along a peripheral portion of the printed circuit board and individually connected to the metal core by way of the plated through-holes: and a plurality of U-shaped leaf springs mounted at the peripheral portion of the printed circuit board in individual contact with the metal lands. each of the U-shaped leaf springs havlng a tongue formed integrally thereon and held in resilien-t contact with the metal film.
In accordance with another aspect of the presen-t invention, there is provided a molded plastic casing, comprising: a metal film formed on an inner face of the casing: a printed clrcuit board accommodated in the ~ `
inside of the casing in such a manner as to divide the inside of the casing into two chambers. the prlnted circuit board having a metal core embedded therein, the metal core being exposed over a predetermined wid-th along an entire perlphery of the prlnted circuit board, the prin-ted circuit board having high frequency functioning circuits mounted on the opposite faces thereof: and a plurality of U-shaped leaf springs ` :`~
mounted at the periphery o-f the printed circui-t board along which the metal core is exposed in such a manner as to grip -the me-tal core. each of the U-shaped leaf . " ,;, . . , ~ ~ i .: :
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-springs having a tongue formed integrally thereon and ::
held in resilient contact with the metal film. :
Alternatively, the metal core of the printed circuit board may be exposed at only one of -the opposite faces thereof over a predetermined vidth along an entir0 periphery of the printed circuit board. .
The above and o-ther obJects, features and .
advantages of the present invention and the manner of realizing them will become more apparent, and the invention itself will best be understood, from a study of the following description and appended claims with reference to the a-ttached drawings showing some preferred embodiments of the invention.
Brief Description of the Drawings FIG. 1 is an explosed sectional view o-E a first embodiment of the present invention:
FIG. 2 is an enlarged sectlonal view of a leaf spring mounting portion of the firs-t embodiment;
FIG. 3 is a perspective view of a leaf spring with a tongue:
FIG. 4A is a sectional view of a leaf spring mounting portion according to a second embodiment of the present invention: :
. . - . ;: . , . ~ . . . . .
FIG. 4B is a sectional view of a leaf spring moun-ting portion according to a third embodiment of the present invention: and FIG. 5 is a sectional view wherein the present invention is applied to a molded plastic casing of a portable telephone set.
Description of the Preferred Embodiments Referring to FIG. 1, there is shown an exploded sectional view of a first embodiment of the present invention. A molded plastic casing 2 is constituted ` , from a front casing 4 and a rear casing 6. A step 4a is formed along an entire periphery of an openlng portion of the front casing 4. and a plurallty of rlbs ~ are formed in a substantially equidistantly spaced relatlonshlp from each other on an lnner face of the front caslng 4. A vapor deposlted fllm 10 of alumlnum --is formed on the entire lnner face of -the front casing 4. The aluminum vapor deposited film 10 may be replaced by a plated film of aluminum or such film may otherwise be formed by electrostatic painting.
A step 6a which is so shaped as -to just fit with the step 4a of the front casing 4 is formed at an opening portion of the rear caising 6, and a plurality of - : :, . i: ~ :. , ,. :
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ribs 12 are -formed at locations of an inner face thereof corresponding to the ribs 8 of the front casing 4. A
vapor deposited film 14 of aluminum is formed on the entire inner face of the rear casing 6 similarly to the front casing 4. Similarly, the aluminum vapor deposi-ted film 14 may be raplaced by a plated film of aluminum or such film may otherwise be formed by electrostatic painting.
Reference numeral l6 denotes a metal core printed circuit board, which has a core 18 of aluminum embedded therein. The core 18 i~ plated with copper or nickel so as to provide connection between the core 18 and plated through-holes 20. A plurality of metal lands 22 are formed on the opposite front and rear faces along a periphery of the metal core printed eircuit board 16 and are eonneeted -to the aluminum eore 18 by way of the plated through-holes 20.
Referenee numeral 24 denotes a leaf spring having a plurality of ton8ues 24a formed integrally ~:
thereon as shown in a perspeetive vlew of FIG. 3. The leaf spring 24 has a substantially U-shape in section and is mounted at a portion of each pair of lands 22 formed on the fron-t and rear faces of the metal core printed circuit board 16 as shown in an enlarged .. . ,. -., . .. : . ., ,~
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sectional view of FIG. 2. Such leaf springs 24 are mounted on four sides of the metal core printed circuit board 16.
In assembling the molded plastic casing 2, the fron-t casing 4 and the rear casing 6 are fitted at -the steps 4a and 6a thereof with each other in such a manner that the metal core printed circuit board 16 is held between the ribs 8 of the front casin~ 4 and the ribs 12 of the rear casing 6. Then, the front casing 4 and the rear casing 6 are coupled integrally with each other by means of screws not shown. As a result of such assembly, the tongues 24a of the leaf springs 24 are contacted resiliantly with the aluminum vapor deposited fllm lO oi' the front caslng 4, and consequently, the two ::
chambers formed in the inside of tho caslng 2 can be electromagnetlcally shielded completely. For example, logic clrcuit parts are carried on the front surface of ' -the metal core printed circuit board 16 while transmitter/receiver circuit parts are carried on the 20 rear surface of the metal core printed circuit board 16. ~.
Referring now to FIG. 4A, there is shown a sectional view of a leai spring mounting portion of a second embodiment of the present invention. In the present embodiment, the core 18 of aluminum is exposed ... , ~ ..... .. . . . . . ..
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fully along an en-tire periphery 18a thereof, and leaf springs 24 each having a plurality of tongues 24a are mounted a-t the exposed portion 18a of -the core 18.
Referring now to FIG. 4B, -there is shown a sectional view of a leaf spring mounting portion of a third embodiment of the present invention. In the present embodiment, the core 18 of aluminum is exposed only at one of the opposlte faces thereof along an en-tire periphery of an outer peripheral portion 18b thereof, and leaf springs 24 each having a plurality of tongues 24a are mounted such that tlle exposed core 18b is gripped by the leaf springs 24.
Where the leaf springs 24 are con-tacted directly with the core 18 oF the prlnted circui-t board 16 a~
~5 shown in FIG. 4A or 4B, the casing can be -formed wlth a reduced thickness. Further, pla-ted through-holes for connecting the core 18 to the leaf springs 24 are urlnecessary.
Even where an outer peripheral portion o-f a metal core printed circuit board is worked in such a manner as shown in FIG. 4A or 4B, if the molded plastic casing 2 is assembled with the metal core printed circuit board 16 held between the front casing 4 and the rear casing 6, then -the tongues 24a of the leaf springs .
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24 are contacted resiliently with the aluminum vapor deposited film 10 formed on -the inner face of the front casing 4, and consequently, an electromagnetic shielding effect similar to that of -the first embodiment described hereinabove can be obtained.
Referring now to FI~. 5, there is shown a sectional view of a casing of a portable telephone set to which an electromagnetic shield structure of the present invention is applied. A molded plastic casing 10 32 of the portable telephone set is cons-tituted from a -front casing 3~ and a rear casing 36. A plurality of ribs 38 are prov:ided in a substantially equidistantly spaced relationship from each other on an inner face of the front caslng 34. A vapor depos.lt0d film not shown of aluminum is formed on the entire inner face of the front casing 34.
A plurality of ribs 40 are formed also at locations of an inner face of the rear casing 36 opposing to the ribs 38 of the front casing 3~. A ~apor deposited film not shown of aluminum is formed on the entire inner face of the rear caslng 36.
A metal core prin-ted circuit board 42 having a core 44 of aluminum embedded therein is accommodated in the casing 32. If the front casing 34 and the rear - . . : :., ,~ . . , casing 36 are secured to each other by means of screws 46 and 48, then the printed circuit board 42 is supported from the opposite sides thereof by the opposing ribs 38 and 40 of the front and rear casings 34 and 36. Logic circuit parts not shown of the por-table telephone set are carried on a front surface of the printed circuit board 42 while transmi-t-ter/receiver circuit parts not shown are carried similarly on a rear surface of the printed circuit board 42.
The core 44 of the printed circuit board 42 is exposed completely over an entire periphery at an outer peripheral portion 44a thereof similarly as in the embodiment shown in FIG. 4A. Thus, if leaf springs 24 each having a plurali-ty of tongues 24a are mounted a-t the exposed portion 44a of the core 44 of the printed circuit board 42, then the tongues 2~a thereo~ are contacted reslllerltly wlth the alumlnum vapor deposlted film not shown formed on the inner face of the casing 42 so that the two chambers in the casing 32 defined by the metal core printed circuit board 42 can be electromagnetically shielded completely.
In each of the embodimen-ts described above, a core of a metal core printed circuit board has a function of electromagne-tically shielding two chambers :.
defined thereby in a casing and also has a heat radiating effect as a heat sink.
', :: `' :, .: ,:: , ,:
ELECTROMAGNETIC SHIELDING STRUCTURE
Field of the Invention This invention relates to a shielding structure for a molded plastic casin~ with a high frequency -functioning circuit built therein.
Background of the Invention An ultimate object of communications is ~ ;
naturally to immediately transmit or exchange a will or information from any place to any person at any time, and moblle communications have been and are being developed gradually in addltion to conventional communlcations between flxed points. Moblle communications include communications be-tween a mobile body such as a ship, an automobile or an aircraft and a general subscriber's statlon, an offlce or the like and communications between mobile bodies, and automobile telephones, portable telephones, cordless telephones are included in such mobile communications.
Among ~uch mobile communlcatlons, wlreless apparatus such as portable telephones or -the like ~ ;
require use of a thin caslng due to a demand for , - . :"
:- . ; :~
reduction in size and weight, and electronic par-ts moun-ted in a high density are accommodated in such casing. Since a high frequency band of 800 to 900 MHz called quasl-microwave band is utilized for such radio equipment, it is required to strengthen electromagnetic shielding of the inside of a casing while reducing the weight of -the casing to prevent various possible impediments which may arise from electromagnetic interference.
10In a conventional construction wherein -the inside of a molded plastic casing such as a casing of a portable telephone set is divided in-to two sections by a printed circult board, U-shaped springs are soldered to ground patterns of the printed clrcuit board while a metal film is formed by platlng, elec-trostatlc painting, vapor deposition of aluminum or the like on an inner face of the molded plastic caslng having ribs, and the U-shaped springs are angaged wlth the rlbs to establish contact therebetween.
With such conven-tional electromagnetic shielding structure, however, since U-shaped springs are soldered to a printed circuit board, there is a problem that many ~ .
steps are required for mounting of such springs.
Besides, as reduction in size and weight of a radio 2 ~;., .
... .
,:
, :::
~ .: ., 2 ` - ~` 3 -~ ~
appara-tus of a portable telephone set or the like proceeds, electronic parts must necessarily be mounted in a high density on a princed circuit board, and such conventional electromagnetic shielding structure cannot cope with such high densi-ty mounting of electronic parts.
Summary of the Invention Aceordingly, lt is an obJect of the present invention to provide an eleetromagnetie shielding strueture for a molded plastic easing by whieh the inside of the easing in whieh a high frequeney funetioning elreuit ls aecommodated can be eleetromagnetleally shlelded wlth a simple structure.
In aeeordanea with an aspeet of the present invention, there is provided a molded plastie casing, eomprising: a metal film formed on an inner ~aee of the casing: a prlnted eireuit board aeeommodated in the inside of the easing in sueh a manner as to divide the inside of the easing into two chambers, the printed eireuit board having a metal eore embedded therein and having a plurallty of plated through-holes formed therein, the printed eireuit board having hiBh frequeney ~ .
functioning clrcuits mounted on the opposite faces ,, . ' ~ ' ~ ' : ' ' ; - :
;
:
,, ~..
-thereof; a plurality of metal lands formed on the opposite faces along a peripheral portion of the printed circuit board and individually connected to the metal core by way of the plated through-holes: and a plurality of U-shaped leaf springs mounted at the peripheral portion of the printed circuit board in individual contact with the metal lands. each of the U-shaped leaf springs havlng a tongue formed integrally thereon and held in resilien-t contact with the metal film.
In accordance with another aspect of the presen-t invention, there is provided a molded plastic casing, comprising: a metal film formed on an inner face of the casing: a printed clrcuit board accommodated in the ~ `
inside of the casing in such a manner as to divide the inside of the casing into two chambers. the prlnted circuit board having a metal core embedded therein, the metal core being exposed over a predetermined wid-th along an entire perlphery of the prlnted circuit board, the prin-ted circuit board having high frequency functioning circuits mounted on the opposite faces thereof: and a plurality of U-shaped leaf springs ` :`~
mounted at the periphery o-f the printed circui-t board along which the metal core is exposed in such a manner as to grip -the me-tal core. each of the U-shaped leaf . " ,;, . . , ~ ~ i .: :
: :. . .:- , ~
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.: . . .
-springs having a tongue formed integrally thereon and ::
held in resilient contact with the metal film. :
Alternatively, the metal core of the printed circuit board may be exposed at only one of -the opposite faces thereof over a predetermined vidth along an entir0 periphery of the printed circuit board. .
The above and o-ther obJects, features and .
advantages of the present invention and the manner of realizing them will become more apparent, and the invention itself will best be understood, from a study of the following description and appended claims with reference to the a-ttached drawings showing some preferred embodiments of the invention.
Brief Description of the Drawings FIG. 1 is an explosed sectional view o-E a first embodiment of the present invention:
FIG. 2 is an enlarged sectlonal view of a leaf spring mounting portion of the firs-t embodiment;
FIG. 3 is a perspective view of a leaf spring with a tongue:
FIG. 4A is a sectional view of a leaf spring mounting portion according to a second embodiment of the present invention: :
. . - . ;: . , . ~ . . . . .
FIG. 4B is a sectional view of a leaf spring moun-ting portion according to a third embodiment of the present invention: and FIG. 5 is a sectional view wherein the present invention is applied to a molded plastic casing of a portable telephone set.
Description of the Preferred Embodiments Referring to FIG. 1, there is shown an exploded sectional view of a first embodiment of the present invention. A molded plastic casing 2 is constituted ` , from a front casing 4 and a rear casing 6. A step 4a is formed along an entire periphery of an openlng portion of the front casing 4. and a plurallty of rlbs ~ are formed in a substantially equidistantly spaced relatlonshlp from each other on an lnner face of the front caslng 4. A vapor deposlted fllm 10 of alumlnum --is formed on the entire lnner face of -the front casing 4. The aluminum vapor deposited film 10 may be replaced by a plated film of aluminum or such film may otherwise be formed by electrostatic painting.
A step 6a which is so shaped as -to just fit with the step 4a of the front casing 4 is formed at an opening portion of the rear caising 6, and a plurality of - : :, . i: ~ :. , ,. :
,. . . . : , , : .. .:
. :. ~ . .,, . . -:: ' , ~ :, , . . .
ribs 12 are -formed at locations of an inner face thereof corresponding to the ribs 8 of the front casing 4. A
vapor deposited film 14 of aluminum is formed on the entire inner face of the rear casing 6 similarly to the front casing 4. Similarly, the aluminum vapor deposi-ted film 14 may be raplaced by a plated film of aluminum or such film may otherwise be formed by electrostatic painting.
Reference numeral l6 denotes a metal core printed circuit board, which has a core 18 of aluminum embedded therein. The core 18 i~ plated with copper or nickel so as to provide connection between the core 18 and plated through-holes 20. A plurality of metal lands 22 are formed on the opposite front and rear faces along a periphery of the metal core printed eircuit board 16 and are eonneeted -to the aluminum eore 18 by way of the plated through-holes 20.
Referenee numeral 24 denotes a leaf spring having a plurality of ton8ues 24a formed integrally ~:
thereon as shown in a perspeetive vlew of FIG. 3. The leaf spring 24 has a substantially U-shape in section and is mounted at a portion of each pair of lands 22 formed on the fron-t and rear faces of the metal core printed circuit board 16 as shown in an enlarged .. . ,. -., . .. : . ., ,~
: ,~
:; .. : ~ ~ .
.;
., 2 ' ' ..,~
sectional view of FIG. 2. Such leaf springs 24 are mounted on four sides of the metal core printed circuit board 16.
In assembling the molded plastic casing 2, the fron-t casing 4 and the rear casing 6 are fitted at -the steps 4a and 6a thereof with each other in such a manner that the metal core printed circuit board 16 is held between the ribs 8 of the front casin~ 4 and the ribs 12 of the rear casing 6. Then, the front casing 4 and the rear casing 6 are coupled integrally with each other by means of screws not shown. As a result of such assembly, the tongues 24a of the leaf springs 24 are contacted resiliantly with the aluminum vapor deposited fllm lO oi' the front caslng 4, and consequently, the two ::
chambers formed in the inside of tho caslng 2 can be electromagnetlcally shielded completely. For example, logic clrcuit parts are carried on the front surface of ' -the metal core printed circuit board 16 while transmitter/receiver circuit parts are carried on the 20 rear surface of the metal core printed circuit board 16. ~.
Referring now to FIG. 4A, there is shown a sectional view of a leai spring mounting portion of a second embodiment of the present invention. In the present embodiment, the core 18 of aluminum is exposed ... , ~ ..... .. . . . . . ..
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fully along an en-tire periphery 18a thereof, and leaf springs 24 each having a plurality of tongues 24a are mounted a-t the exposed portion 18a of -the core 18.
Referring now to FIG. 4B, -there is shown a sectional view of a leaf spring mounting portion of a third embodiment of the present invention. In the present embodiment, the core 18 of aluminum is exposed only at one of the opposlte faces thereof along an en-tire periphery of an outer peripheral portion 18b thereof, and leaf springs 24 each having a plurality of tongues 24a are mounted such that tlle exposed core 18b is gripped by the leaf springs 24.
Where the leaf springs 24 are con-tacted directly with the core 18 oF the prlnted circui-t board 16 a~
~5 shown in FIG. 4A or 4B, the casing can be -formed wlth a reduced thickness. Further, pla-ted through-holes for connecting the core 18 to the leaf springs 24 are urlnecessary.
Even where an outer peripheral portion o-f a metal core printed circuit board is worked in such a manner as shown in FIG. 4A or 4B, if the molded plastic casing 2 is assembled with the metal core printed circuit board 16 held between the front casing 4 and the rear casing 6, then -the tongues 24a of the leaf springs .
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24 are contacted resiliently with the aluminum vapor deposited film 10 formed on -the inner face of the front casing 4, and consequently, an electromagnetic shielding effect similar to that of -the first embodiment described hereinabove can be obtained.
Referring now to FI~. 5, there is shown a sectional view of a casing of a portable telephone set to which an electromagnetic shield structure of the present invention is applied. A molded plastic casing 10 32 of the portable telephone set is cons-tituted from a -front casing 3~ and a rear casing 36. A plurality of ribs 38 are prov:ided in a substantially equidistantly spaced relationship from each other on an inner face of the front caslng 34. A vapor depos.lt0d film not shown of aluminum is formed on the entire inner face of the front casing 34.
A plurality of ribs 40 are formed also at locations of an inner face of the rear casing 36 opposing to the ribs 38 of the front casing 3~. A ~apor deposited film not shown of aluminum is formed on the entire inner face of the rear caslng 36.
A metal core prin-ted circuit board 42 having a core 44 of aluminum embedded therein is accommodated in the casing 32. If the front casing 34 and the rear - . . : :., ,~ . . , casing 36 are secured to each other by means of screws 46 and 48, then the printed circuit board 42 is supported from the opposite sides thereof by the opposing ribs 38 and 40 of the front and rear casings 34 and 36. Logic circuit parts not shown of the por-table telephone set are carried on a front surface of the printed circuit board 42 while transmi-t-ter/receiver circuit parts not shown are carried similarly on a rear surface of the printed circuit board 42.
The core 44 of the printed circuit board 42 is exposed completely over an entire periphery at an outer peripheral portion 44a thereof similarly as in the embodiment shown in FIG. 4A. Thus, if leaf springs 24 each having a plurali-ty of tongues 24a are mounted a-t the exposed portion 44a of the core 44 of the printed circuit board 42, then the tongues 2~a thereo~ are contacted reslllerltly wlth the alumlnum vapor deposlted film not shown formed on the inner face of the casing 42 so that the two chambers in the casing 32 defined by the metal core printed circuit board 42 can be electromagnetically shielded completely.
In each of the embodimen-ts described above, a core of a metal core printed circuit board has a function of electromagne-tically shielding two chambers :.
defined thereby in a casing and also has a heat radiating effect as a heat sink.
', :: `' :, .: ,:: , ,:
Claims (6)
1. A molded plastic casing, comprising:
a metal film formed on an inner face of said casing:
a printed circuit board accommodated in the inside of said casing in such a manner as to divide the inside of said casing into two chambers, said printed circuit board having a metal core embedded therein and having a plurality of plated through-holes formed therein, said printed circuit board having high frequency functioning circuits mounted on the opposite faces thereof:
a plurality of metal lands formed on the opposite faces along a peripheral portion of said printed circuit board and individually connected to said metal core by way of said plated through-holes; and a plurality of U-shaped leaf springs mounted at the peripheral portion of said printed circuit board in individual contact with said metal lands, each of said U-shaped leaf springs having a tongue formed integrally thereon and held in resilient contact with said metal film.
a metal film formed on an inner face of said casing:
a printed circuit board accommodated in the inside of said casing in such a manner as to divide the inside of said casing into two chambers, said printed circuit board having a metal core embedded therein and having a plurality of plated through-holes formed therein, said printed circuit board having high frequency functioning circuits mounted on the opposite faces thereof:
a plurality of metal lands formed on the opposite faces along a peripheral portion of said printed circuit board and individually connected to said metal core by way of said plated through-holes; and a plurality of U-shaped leaf springs mounted at the peripheral portion of said printed circuit board in individual contact with said metal lands, each of said U-shaped leaf springs having a tongue formed integrally thereon and held in resilient contact with said metal film.
2. A molded plastic casing according to claim 1.
wherein said molded plastic casing is constituted from a front casing and a rear easing each having a plurality of ribs formed integrally thereon in a spaced relationship from each other such that, when said front and rear casings are integrated with each other, said printed circuit board are supported between and by said ribs of said front and rear casings.
wherein said molded plastic casing is constituted from a front casing and a rear easing each having a plurality of ribs formed integrally thereon in a spaced relationship from each other such that, when said front and rear casings are integrated with each other, said printed circuit board are supported between and by said ribs of said front and rear casings.
3. A molded plastic casing, comprising:
a metal film formed on an inner face of said casing:
a printed circuit board accommodated in the inside of said casing in such a manner as to divide the inside of said easing into two chambers, said printed circuit board having a metal core embedded therein, said metal core being exposed over a predetermined width along an entire periphery of said printed circuit board, said printed circuit board having high frequency functioning circuits mounted on the opposite faces thereof: and a plurality of U-shaped leaf springs mounted at the periphery of said printed circuit board along which said metal core is exposed in such a manner as to grip the metal core, each of said U-shaped leaf springs having a tongue formed integrally thereon and held in resilient contact with said metal film.
a metal film formed on an inner face of said casing:
a printed circuit board accommodated in the inside of said casing in such a manner as to divide the inside of said easing into two chambers, said printed circuit board having a metal core embedded therein, said metal core being exposed over a predetermined width along an entire periphery of said printed circuit board, said printed circuit board having high frequency functioning circuits mounted on the opposite faces thereof: and a plurality of U-shaped leaf springs mounted at the periphery of said printed circuit board along which said metal core is exposed in such a manner as to grip the metal core, each of said U-shaped leaf springs having a tongue formed integrally thereon and held in resilient contact with said metal film.
4. A molded plastic casing according to claim 3, wherein said molded plastic casing is constituted from a front casing and a rear casing each having a plurality of ribs formed integrally thereon in a spaced relationship from each other such that, when said front and rear casings are integrated with each other, said printed circuit board are supported between and by said ribs of said front and rear casings.
5. A molded plastic casing, comprising:
a metal film formed on an inner face of said casing;
a printed circuit board accommodated in the inside of said casing in such a manner as to divide the inside of said casing into two chambers, said printed circuit board having a metal core embedded therein, said metal core being exposed at one of the opposite faces thereof over a predetermined width along an entire periphery of said printed circuit board: and a plurality of U-shaped leaf springs mounted at the periphery of said printed circuit board along which said metal core is exposed in such a manner as to grip the metal core, each of said U-shaped leaf springs having a tongue formed integrally thereon and held in resilient contact with said metal film.
a metal film formed on an inner face of said casing;
a printed circuit board accommodated in the inside of said casing in such a manner as to divide the inside of said casing into two chambers, said printed circuit board having a metal core embedded therein, said metal core being exposed at one of the opposite faces thereof over a predetermined width along an entire periphery of said printed circuit board: and a plurality of U-shaped leaf springs mounted at the periphery of said printed circuit board along which said metal core is exposed in such a manner as to grip the metal core, each of said U-shaped leaf springs having a tongue formed integrally thereon and held in resilient contact with said metal film.
6. A molded plastic casing according to claim 5.
wherein said molded plastic casing is constituted from a front casing and a rear casing each having a plurality of ribs formed integrally thereon in a spaced relationship from each other such that, when said front and rear casings are integrated with each other, said printed circuit board are supported between and by said ribs of said front and rear casings.
wherein said molded plastic casing is constituted from a front casing and a rear casing each having a plurality of ribs formed integrally thereon in a spaced relationship from each other such that, when said front and rear casings are integrated with each other, said printed circuit board are supported between and by said ribs of said front and rear casings.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23566290A JPH04116899A (en) | 1990-09-07 | 1990-09-07 | Shielding structure of molded resin case |
| JP02-235662 | 1990-09-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2050851A1 true CA2050851A1 (en) | 1992-03-08 |
Family
ID=16989339
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2050851 Abandoned CA2050851A1 (en) | 1990-09-07 | 1991-09-06 | Molded plastic casing with electromagnetic shielding structure |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JPH04116899A (en) |
| AU (1) | AU627666B2 (en) |
| CA (1) | CA2050851A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5946194A (en) * | 1993-12-23 | 1999-08-31 | Symbol Technologies, Inc. | Memory card assembly having an integral antenna |
| US6111746A (en) * | 1997-11-21 | 2000-08-29 | Dell Usa, L.P. | Computer processor module ground/EMI-shield spring clip and method |
| US6295031B1 (en) | 1993-12-23 | 2001-09-25 | Symbol Technologies, Inc. | Memory card assembly having an integral antenna |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5339222A (en) * | 1993-04-06 | 1994-08-16 | The Whitaker Corporation | Shielded printed circuit card holder |
| JPH07283573A (en) * | 1994-04-12 | 1995-10-27 | Nec Corp | Shield |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2529430B1 (en) * | 1982-06-25 | 1985-08-09 | Telecommunications Sa | SHIELDING STRUCTURE FOR AN ELECTRICAL CIRCUIT, FOR EXAMPLE MICROWAVE, ITS MOUNTING METHOD AND THE TOOLS FOR IMPLEMENTING SAID STRUCTURE |
| US4872091A (en) * | 1986-07-21 | 1989-10-03 | Ricoh Company, Ltd. | Memory cartridge |
| JP2631544B2 (en) * | 1989-01-27 | 1997-07-16 | 日本シイエムケイ株式会社 | Printed wiring board |
-
1990
- 1990-09-07 JP JP23566290A patent/JPH04116899A/en active Pending
-
1991
- 1991-09-06 CA CA 2050851 patent/CA2050851A1/en not_active Abandoned
- 1991-09-06 AU AU83721/91A patent/AU627666B2/en not_active Ceased
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5946194A (en) * | 1993-12-23 | 1999-08-31 | Symbol Technologies, Inc. | Memory card assembly having an integral antenna |
| US6295031B1 (en) | 1993-12-23 | 2001-09-25 | Symbol Technologies, Inc. | Memory card assembly having an integral antenna |
| US6111746A (en) * | 1997-11-21 | 2000-08-29 | Dell Usa, L.P. | Computer processor module ground/EMI-shield spring clip and method |
Also Published As
| Publication number | Publication date |
|---|---|
| AU8372191A (en) | 1992-04-30 |
| JPH04116899A (en) | 1992-04-17 |
| AU627666B2 (en) | 1992-08-27 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Dead |