WO2009012723A1

WO2009012723A1 - Shielding device

Info

Publication number: WO2009012723A1
Application number: PCT/CN2008/071761
Authority: WO
Inventors: Steven Shen
Original assignee: Laird Technologies (Shanghai) Co., Ltd.
Priority date: 2007-07-25
Filing date: 2008-07-25
Publication date: 2009-01-29
Also published as: CN101355867B; CN101355867A

Abstract

A shielding device (1) for shielding at least one electronic element (13) disposed on a printed circuit board (PCB)(10), which has a frame (2) and a shielding case (3) engaging with the frame (2) and electrically connected thereto. The lower side of the frame (2) is provided with elastic sheets (24) that elastically and electrically contact a welding-pad (11) on the PCB (10), and the frame (2) is further provided with first mounting holes (23) that are aligned with screw holes (12) on the PCB (10) and allow screws (4) to pass therethrough. The shielding case (3) is provided with second mounting holes (32) that are aligned with the first mounting holes (23) and allow the screws (4) to pass therethrough. The screws (4) are sequentially passed through the second mounting holes (32), the first mounting holes (23), and are threaded into the screw holes (12) on the PCB (10), so as to fix the shielding case (3) and the frame (2) onto the PCB (10).

Description

SHIELDING DEVICE

Technical Field

The present invention relates to a shielding device for preventing electromagnetic interference (EMI), and more particularly, to a shielding device adapted to providing EMI shielding for one or more electric components on a substrate.

Background of the Invention

The descriptions in this section only provide background information related to the disclosure of the present invention, and do not constitute the prior art.

In normal operations, electronic/electrical components in an equipment often generate undesired electromagnetic energy, which may interfere in operations of neighboring electronic/electrical components due to EMI transmission caused by radiation. In order to eliminate or at least reduce the negative influence caused by the EMI, a shielding case/device may be used to shield electronic/electrical components from EMI.

One usual conventional shielding device is of a two-piece structure wherein a cover is mounted to a frame. Another usual conventional shielding device is of a one-piece structure, i.e., the shielding device consists of one component.

A conventional shielding case is usually fixed on a printed circuit board (PCB) through SMT welding. In case of a shielding device of a one-piece structure, if electronic elements (e.g., IC parts or the like) surrounded by the shielding device need to be maintained after the shielding device is welded onto the PCB, the maintainer will have to break the welding joints so as to remove the shielding case, thus the electronic elements surrounded by the shielding device are very likely to be damaged, and the maintenance is also very inconvenient. In case of a shielding device of a two-piece structure, the frame is welded onto the PCB, and the cover is mounted onto the frame, thus a mounting structure between the cover and the frame is very firm, which prevents the cover from dropping off the frame accidentally; when a maintenance is carried out, the cover should be removed with a large external force, and remounted after the maintenance is finished, so the electronic elements are likely to be damaged when the cover is removed from the frame. Furthermore, the frame may present an obstacle to maintenance. In addition, it is inconvenient to maintain such a structure.

Meanwhile, with respect to the shielding device of a two-piece structure, an internal elastic shielding sheet and an external metal drawing part are generally connected to each other via a laser welding method. The welding quality affects the shielding performance significantly, thus the performance of the fabricated shielding device tends to be degraded or destabilized; besides, the fabricating process is complicated, and the production efficiency and yield are also low.

Summary of the Invention

The aim of the present invention is to provide a shielding device that overcomes the defects of the current shielding device, and facilitate dismounting so as to conveniently maintain electronic elements surrounded by the shielding device.

One embodiment of the present invention provides a shielding device for shielding at least one electronic element disposed on a PCB. The shielding device has a frame and a shielding case engaging with the frame and electrically connected thereto. The lower side of the frame is provided with elastic sheets that elastically and electrically contact a welding-pad on the PCB, and the frame is further provided with a first mounting hole that is aligned with screw holes on the PCB and allow screws to pass therethrough. In addition, the shielding case is provided with a second mounting hole that is aligned with the first mounting hole and allows the screw to pass therethrough. The screw is sequentially passed through the second mounting hole and the first mounting hole, and is threaded into the screw hole on the PCB so as to fix the shielding case and the frame onto the PCB.

With the above structure, the present invention fixes the shielding device onto the PCB via a method other than welding, and the shielding case and the frame are also fixed to each other by same screws. Thus it only needs to loosen the screws when the electronic element in the shielding device is to be maintained, and the shielding case and the frame can be removed from the PCB simultaneously. Furthermore, re-welding and re-assembly are dispensed. In addition, it is not necessary to make use of laser welding to connect the frame and the shielding case according to the invention, which, after engaging with each other, can be fixed by screws relative to each other.

As compared with a current shielding device of a one-piece or two-piece structure, the present invention needs no SMT welding, resulting in cost and energy saving. Besides, as compared with the current conventional shielding devices, the present invention presents a firm structure, which improves the performance of the PCB in drop tests and torsion tests. In addition, it not necessary in the present invention to weld the frame and the shielding case of the shielding device, thus the process is simple and reliable, and the production efficiency and yield are also high.

In one embodiment of the present invention, a snap slot is provided on one of the frame and the shielding case, and an engaging convex portion that is to be engaged with the snap slot is provided on the corresponding position of the other one of the frame and the shielding case. Such an engaging structure can enhance the connection between the frame and the shielding case, and facilitate mounting. In a further embodiment, an internal side of the snap slot is provided with engaging contact bump, while the engaging convex portion is provided with engaging hole or engaging concave portion to be engaged with the engaging contact bump. With engagements between the engaging contact bump and the engaging hole or engaging concave portion, the frame and the shielding case may be connected to each other conveniently and firmly.

In one embodiment, the snap slot or the engaging convex portion may be disposed on a peripheral wall of the frame or the shielding case, i.e., the snap slot is disposed on the peripheral wall of one of the frame and the shielding case, and the engaging convex portion is disposed correspondingly on a peripheral wall of the other one of the frame and the shielding case. In addition, engaging structures may also be disposed at a position interior of the peripheral walls of the frame and the shielding case, i.e., the snap slot is disposed at a position interior of the peripheral wall of one of the frame and the shielding case, and the engaging convex portion is disposed correspondingly on the other one of the frame and the shielding case. As a particular structure, a plurality of snap slots are disposed at the position interior of the peripheral wall of one of the frame and the shielding case, and the snap slots are disposed to separate a region surrounded or covered by one of the frame and the shielding case into a plurality of separated sections, and hence a shielding device may be used to shield a plurality of electronic elements separately.

In one detailed embodiment, an external wall of the shielding case is formed as part of the engaging convex portion, so that the structure can be further simplified.

In one embodiment, the snap slot is configured in an approximate U-shape, or in a right-angled frame shape with one side open. The engaging contact bump is disposed on internal sides of two side walls opposing each other of the snap slot. Furthermore, as a particular structure, a peripheral portion of the engaging contact bump has a guiding bevel or guiding arc to facilitate engagement with and disengagement from the engaging hole or the engaging concave portion, so that the frame and the shielding case can be connected to and separated from each other easily. As another particular structure, the peripheral portion of the engaging contact bump is provided with an engaging locking portion to facilitate engagement lock with the engaging hole or engaging concave portion and prevent disengagement, so that the frame and the shielding case are more firmly connected to each other. Preferably, the external wall of the shielding case is formed as part of the engaging convex portion, an edge portion of the external wall extends outward from the snap slot by a predetermined length, so that the edge portion of the external wall extending beyond the snap slot can act as a holding portion in separating the frame from the shielding case, and the engaging contact bump can be disengaged from the engaging hole or the engaging concave portion by holding and pressing the edge portion of the external wall.

In one embodiment of the shielding device of the present invention, the elastic sheet of the frame is formed by punching from the lower side of the frame, so that one side of the elastic sheet is connected to the lower side of the frame to form a connecting base end, while other three sides detach from the lower side of the frame so as to form a free end, which elastically extends downward with respect to the lower side of the frame. With such a structure, the elastic sheet may be fabricated integrally with the frame, therefore material is saved, structural strength is improved, and the fabricating process is simplified. In one particular structure, the frame is provided with a snap slot opening upward to engage with the engaging convex portion on the shielding case, and the elastic sheet is formed at the lower side of the snap slot. The snap slot and the elastic sheet are disposed at the corresponding positions in upward/downward directions, so that the structure of the frame is more compact and the material is saved.

In one embodiment of the shielding device of the present invention, protruding sheets are disposed on the frame and the shielding case, and extend outward from peripheral walls thereof. The first mounting hole and the second mounting hole are disposed on the protruding sheets respectively, which is convenient for mounting and removing the shielding device without any impedance. In a particular structure, the protruding sheets are formed at respective corners of the frame and the shielding case configured in a rectangular shape.

In one embodiment of the shielding device of the present invention, the protruding sheets can be disposed at positions of the frame and the shielding case which are interior of the peripheral walls thereof and shunt the shielded electronic elements, and the first mounting hole and the second mounting hole are disposed on the protruding sheets respectively. The frame and the shielding case can be fixed more firmly on the PCB by disposing additional protruding sheets at positions outside the peripheral walls that pose no impedance.

Brief Description of the Drawings

Fig. 1 is an exploded perspective view showing a shielding device according to an embodiment of the invention to be mounted onto a PCB;

Fig. 2 is an exploded perspective view showing a frame and a shielding case in a shielding device according to an embodiment of the invention.

Figs. 3a~3e are structural diagrams showing the assembled frame and shielding case in a shielding device according to an embodiment of the invention, wherein Fig. 3a is a front view, Fig. 3b is a left view, Fig. 3c is a right view, Fig. 3d is a top view, and Fig. 3e is a bottom view, respectively, of the assembled state.

Figs. 4a~4e are structural diagrams indicative of a frame in a shielding device according to an embodiment of the invention, wherein Fig. 4a is a front view, Fig. 4b is a left view, Fig. 4c is a right view, Fig. 4d is a top view, and Fig. 4e is a bottom view, respectively, of the frame.

Fig. 5 is an amplified diagram showing an example of elastic sheets on a frame according to the present invention.

Fig. 6 is a partially amplified structural diagram showing a snap slot and engaging contact bumps disposed thereon.

Fig. 7 is a structural diagram showing an example of a snap slot according to the present invention.

Figs. 8a~8e are structural diagrams showing a shielding case of a shielding device in one embodiment of the present invention, wherein Fig. 8a is a front view, Fig. 8b is a left view, Fig. 8c is a right view, Fig. 8d is a top view, and Fig. 8e is a bottom view, respectively, of the shielding case.

Fig. 9 is a structural diagram showing an external wall of a shielding case which constitutes part of the engaging bumps in one embodiment of the present invention.

Detailed Description of the Preferred Embodiment

The details of a particular embodiment of the present invention are described below with reference to the accompanying drawings. However, it should be understood that the following descriptions are merely exemplary in nature and are in no way to limit the disclosure, application or utilization of the present invention.

In the description, some terms used herein are only for reference, and do not limit the present invention. For example, terms, such as "up", "down", "above", "below", "top" and "bottom", indicate directions in the drawing referred to. Terms, such as "front", "backward", "back", "bottom" and "side" describe orientations of respective parts of a component in consistent and arbitrary reference systems, and the reference system is made clear by referring to the text describing the component in question and the related drawings. Such terms may include those explicitly mentioned above, their derivatives and other words of similar meanings. Similarly, terms "first", "second" and other similar numerals do not imply any sequence or order, unless otherwise specified.

When elements or features, and exemplary embodiments are described, articles "a", "an", "the" and "said" mean one or more such components or features, while terms "including", "comprising" and "having" have an inclusive meaning, and there may be additional elements or features besides those having been mentioned.

In one embodiment of the present invention, there is provided a shielding device 1 for shielding at least one electronic element 13 disposed on a PCB 10, as shown in Fig. 1. The shielding device 1 has a frame 2 and a shielding case 3 engaging with the frame 2 and electrically connected thereto. The lower side of the frame 2 is provided with elastic sheets 24 that elastically and electrically contact a welding-pad 11 arranged on the PCB 10 (see Fig. 5), and the frame 2 is further provided with first mounting holes 23 that are aligned with screw holes 12 arranged on the PCB 10 and allow screws 4 to pass therethrough. In addition, the shielding case 3 is provided with second mounting holes 32 that are aligned with the first mounting holes 23 and allow the screws 4 to pass therethrough. The shielding case 3 and the frame 2 are fixed onto the PCB 10 by sequentially passing screws 4 through the second mounting holes 32 and the first mounting holes 23, and by threading these screws into the screw holes 12 on the PCB 10.

With the above structure, the present invention fixes the shielding device 1 onto the PCB 10 via a fixing method other than welding, and the shielding case 3 and the frame 2 are also fixed to each other by same screws 4. Thus, it only needs to loosen the screws 4 when the electronic element 13 in the shielding device 1 is to be maintained, and the shielding case 3 and the frame 2 can be removed from the PCB 10 simultaneously. Furthermore, re-welding and re-assembly are dispensed. In addition, it is not necessary, according to the invention, to make use of laser welding to connect the frame 2 and the shielding case 3, which, after engaging with each other, can be fixed by screws 4 relative to each other.

In addition, as the elastic sheets 24 disposed at the lower side of the frame 2 elastically and electrically contact the pad 11 on the PCB 10, the frame 2 (shielding device 1 ) is electrically connected to the PCB 10 at the same time when the frame 2 and the shielding case 3 are mounted on the PCB 10 with the screws 4, without welding the frame 2 onto the PCB 10, as in the case of prior art shielding devices.

In one embodiment of the present invention, as shown in Figs. 1 and 2, a snap slot 21 is provided on one of the frame 2 and the shielding case 3 (e.g., the frame 2), and an engaging convex portion 35 that is to engage with the snap slot 21 is provided on corresponding position of the other one of the frame 2 and the shielding case 3 (e.g., the shielding case 3). Such an engaging arrangement can enhance the connection between the frame 2 and the shielding case 3, and hence facilitate mounting. Although in the arrangement as shown in Figs. 1~5, the snap slot 21 is provided on the frame 2 and the engaging convex portion 35 is provided on the shielding case 3, it is easy for persons skilled in the art to contemplate other arrangements, e.g. a snap slot 21 disposed on the shielding case 3 and the engaging convex portion 35 on the frame 2, or some of the snap slots 21 and some of the engaging convex portions 35 disposed on the shielding case 3, and others on the frame 2, provided that the snap slots 21 and the engaging convex portions 35 on the frame 2 and the shielding case 3 correspond to each other and may engage with each other.

In one embodiment, the snap slot 21 or the engaging convex portion 35 can be disposed on a peripheral wall of the frame 2 or the shielding case 3, i.e., the snap slot 21 is disposed on a peripheral wall 25 of one of the frame 2 and the shielding case 3 (e.g., the frame 2), and the engaging convex portion 35 is disposed correspondingly on a peripheral wall 36 of the other one of the frame 2 and the shielding case 3 (e.g., the shielding case 3). With the snap slot 21 or the engaging convex portion 35 disposed on the peripheral wall, the frame 2 or the shielding case 3 can be firmly jointed with a small joining structure by means of an engagement between the snap slot 21 and the engaging convex portion 35.

In addition, engaging structures can also be disposed in a part interior of the peripheral walls 25 and 36 of the frame 2 and the shielding case 3, i.e., the snap slot 21 is disposed on a part interior of the peripheral wall 25 of one of the frame 2 and the shielding case 3 (e.g., the frame 2), and the engaging convex portion 35 is disposed correspondingly on the other one of the frame 2 and the shielding case 3 (e.g., the shielding case 3). The snap slot 21 and the engaging convex portion 35 can be set in a single pair, or in a plurality of pairs. As a specific implementation, a plurality of snap slots 21 are disposed on the part interior of the peripheral wall 25 of the frame 2, and they separate a region surrounded or covered by the frame 2 into a plurality of separated sections; correspondingly, the engaging convex portions 35 on the part interior of the peripheral wall 36 of the shielding case 3 are also disposed to separate a region surrounded or covered by the shielding case 3 into a plurality of separated sections. The snap slots 21 and the engaging convex portions 35 can engage with each other correspondingly, thus one shielding device 1 can act to shield a plurality of electronic elements 13 separately.

In one particular embodiment, as shown in Fig. 9, an external wall 33 of the shielding case 3 forms as part of the engaging convex portion 35, so that the structure can be further simplified. In addition, engaging holes 34 may be disposed on the external wall 33.

In one further embodiment, as shown in Fig. 6, an internal side of the snap slot 21 is provided with engaging contact bumps 211 , while the engaging convex portion 35 is provided with engaging holes 34 or engaging concave portions to engage with the engaging contact bumps 211. As shown in Figs. 1 , 2, 3a~3e and 8a~8e, with engagements between the engaging contact bumps 211 and the engaging holes 34 or engaging concave portions, the frame 2 and the shielding case 3 are connected to each other conveniently and firmly. The engaging contact bumps 211 can be formed as bumps that are directly disposed on the internal side of the snap slot 21 , e.g., formed by protrusions welded on the internal side of the snap slot 21. Alternatively, the engaging contact bumps 211 can be formed by protruding part of the internal side inward by pressing the external side of the snap slot 21 toward the internal side. In addition, the engaging holes 34 may be formed by punching side walls of the engaging convex portion 35, or engaging concave portions (not shown in the drawings) may be formed by pressing the side walls of the engaging convex portion 35 to produce concave structures.

In one embodiment, the snap slot 21 is configured in an approximate U-shape, or in a right-angled frame shape with one side open. The engaging contact bumps 211 are disposed on internal sides of two side walls opposing each other of the snap slot 21 , as shown in Fig. 6. Furthermore, as a particular arrangement, a peripheral portion 212 of the engaging contact bump 211 has a guiding bevel or guiding arc to facilitate engagement with and disengagement from the engaging hole 34 or the engaging concave portion, so that the frame 2 and the shielding case 3 can be connected to and separated from each other easily. Although not shown in figures, as another particular arrangement, persons skilled in the art can easily understand and carry out that the peripheral portion 212 of the engaging contact bump 211 is provided with an engaging locking portion to facilitate engagement lock with the engaging hole or engaging concave portion and prevent disengagement. For example, a relatively large angle forms between the surface of the engaging locking portion and the internal side of the snap slot 21 , so that it is difficult for edges of the engaging holes 34 to slide off or drop from the peripheral portion 212 of the engaging contact bump 211 under a normal force application, and hence the frame 2 and the shielding case 3 are connected more firmly to each other. Under this condition, although not shown in the figures, persons skilled in the art may easily carry out that the external wall 33 of the shielding case 3 is preferably formed as part of the engaging convex portion 35, and an edge portion of the external wall 33 extends outward from the snap slot 21 by a predetermined length. In this way, the edge portion of the external wall 33 extending beyond the snap slot can act as a holding portion in separating the frame 2 from the shielding case 3, and the engaging contact bump 211 can be disengaged from the engaging hole 34 or the engaging concave portion by holding and pressing the edge portion of the external wall.

In one embodiment of the shielding device 1 of the present invention, the elastic sheet 24 of the frame 2 is formed by punching from the lower side of the frame 2, so that one side of the elastic sheet 24 is connected to the lower side of the frame so as to form a connecting base end 242, while other three sides detach from the lower side of the frame so as to form a free end 241 , which elastically extends downward with respect to the lower side of the frame 2. With such a structure, the elastic sheet 24 may be fabricated integrally with the frame 2, therefore material is saved, structural strength is improved and the fabricating process is simplified. In one particular structure, the frame 2 is provided with a snap slot 21 opening upward to engage with the engaging convex portion 35 on the shielding case 3, and the elastic sheet 24 is formed at the lower side of the snap slot 21 , as shown in Fig. 7. The snap slot 21 and the elastic sheet 24 are disposed at the corresponding positions in upward/downward directions, so that the structure of the frame 2 is more compact and the material is saved. There may be one or more elastic sheets 24, but preferably, a plurality of elastic sheets 24 are disposed at the lower side of the peripheral wall of the frame 2 so as to come into good contact with the pad on the PCB 10 and be electrically connected thereto. If, on PCB, pads are disposed on positions of the snap slots 21 interior of the peripheral wall of the frame 2, the elastic sheets 24 extending elastically downward will also be disposed at the lower sides of the snap slots 21 correspondingly. In one embodiment of the shielding device of the present invention, protruding sheets 22, 31 are disposed on the frame 2 and the shielding case 3, and extend outward from peripheral walls thereof. The first mounting holes 23 and the second mounting holes 32 are disposed on the protruding sheets 22, 31 , thus the shielding device may be conveniently mounted and dismounted, without any impedance. In a particular arrangement, the protruding sheets 22, 31 are formed at respective corners of the frame 2 and the shielding case 3 configured in a rectangular shape. Of course, these protruding sheets can be disposed at other appropriate positions of the frame 2 and the shielding case 3. For example, in one embodiment of the shielding device 1 of the present invention, although not shown in figures, the protruding sheets can be disposed at positions of the frame 2 and the shielding case 3 which are interior of the peripheral walls thereof and shunt the shielded electronic elements, and the first mounting holes 23 and the second mounting holes 32 are disposed on the protruding sheets. The frame and the shielding case can be fixed more firmly on the PCB by disposing additional protruding sheets at positions outside the peripheral walls that pose no impedance.

The above descriptions are only exemplary in nature, and variations that do not deviate from the gist of the disclosure reside within the scope of the disclosure. Those variations shall not be deemed as deviating from the spirit and scope of the disclosure.

Claims

1. A shielding device for shielding at least one electronic element disposed on a printed circuit board, comprising a frame and a shielding case engaging with the frame and being electrically connected to the frame, characterized in that, the lower side of the frame is provided with a elastic sheet that elastically and electrically contact a welding-pad on the printed circuit board, and the frame is further provided with a first mounting hole that is aligned with a screw hole on the printed circuit board and allows a screw to pass therethrough; the shielding case is provided with a second mounting hole that is aligned with the first mounting hole and allow the screw to pass therethrough; the screw is sequentially passed through the second mounting hole and the first mounting hole, and is threaded into the screw hole on the printed circuit board so as to fix the shielding case and frame onto the printed circuit board.

2. The shielding device according to claim 1 , characterized in that, a snap slot is provided on one of the frame and the shielding case, and an engaging convex portion that is to be engaged with the snap slot is provided on a corresponding position of the other one of the frame and the shielding case.

3. The shielding device according to claim 2, characterized in that, an internal side of the snap slot is provided with an engaging contact bump, and the engaging convex portion is provided with an engaging hole or engaging concave portion to be engaged with the engaging contact bump.

4. The shielding device according to claim 2, characterized in that, the snap slot is disposed on a peripheral wall of the one of the frame and the shielding case, and the engaging convex portion is disposed correspondingly on a peripheral wall of the other one of the frame and the shielding case.

5. The shielding device according to claim 2 or 4, characterized in that, the snap slot is disposed at a position interior of the peripheral wall of the one of the frame and the shielding case, and the engaging convex portion is disposed correspondingly on the other one of the frame and the shielding case.

6. The shielding device according to claim 5, characterized in that, the snap slot disposed at a position interior of the peripheral wall of the one of the frame and the shielding case is dispose to be a plurality of snap slots, and they separate a region surrounded or covered by the one of the frame and the shielding case into a plurality of sections.

7. The shielding device according to claim 2, characterized in that, an external wall of the shielding case is formed as part of the engaging convex portion.

8. The shielding device according to claim 3, characterized in that, the engaging contact bump is disposed on internal sides of two side walls opposing to each other of the snap slot that has an approximately U-shaped cross-section.

9. The shielding device according to claim 3 or 8, characterized in that, a peripheral portion of the engaging contact bump is provided with a guiding bevel or guiding arc to facilitate engagement with and disengagement from the engaging hole or the engaging concave portion.

10. The shielding device according to claim 3 or 8, characterized in that, a peripheral portion of the engaging contact bump is provided with an engaging locking portion to facilitate engagement lock with the engaging hole or engaging concave portion and prevent disengagement.

11. The shielding device according to claim 10, characterized in that, an external wall of the shielding case is formed as part of the engaging convex portion, and an edge portion of the external wall extends outward from the snap slot by a predetermined length.

12. The shielding device according to claim 1 , characterized in that, the elastic sheet of the frame is formed by punching from the lower side of the frame, one side of the elastic sheet is connected to the lower side of the frame so as to form a connecting base end, while other three sides detach from the lower side of the frame so as to form a free end, which elastically extends downward with respect to the lower side of the frame.

13. The shielding device according to claim 12, characterized in that, the frame is provided with a snap slot opening upward to engage with the engaging convex portion on the shielding case, and the elastic sheet is formed at the lower side of the snap slot.

14. The shielding device according to claim 1 , characterized in that, protruding sheets are disposed on the frame and the shielding case and extend outward from peripheral walls thereof, and the first mounting hole and the second mounting hole are disposed on the protruding sheets respectively.

15. The shielding device according to claim 14, characterized in that, the protruding sheets are formed at respective corners of the frame and the shielding case configured in a rectangular shape.

16. The shielding device according to claim 1 , characterized in that, the protruding sheets are disposed at positions of the frame and the shielding case which are interior of the peripheral walls thereof and shunt the shielded electronic elements, and the first mounting hole and the second mounting hole are disposed on the protruding sheets respectively.