DESC:FORM-2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)

Title: A PROTECTIVE COVER ASSEMBLY FOR A KEYBOARD

APPLICANT DETAILS:
(a) NAME: Bharat Electronics Limited
(b) NATIONALITY: Indian
(c) ADDRESS: Outer Ring Road, Nagavara, Bangalore - 560045 Karnataka, India

PREAMBLE TO THE DESCRIPTION:
The following specification (particularly) describes the nature of the invention (and the manner in which it is to be performed):
A PROTECTIVE COVER ASSEMBLY FOR A KEYBOARD

FIELD OF INVENTION:
The present invention relates to a protective cover assembly for a keyboard that is flexible and provide protection to electronic devices/equipment from environment and electromagnetic interfaces /electromagnetic compatibility (EMI/EMC). The protective cover is a sandwiched structure that shields tactile functional keys and enables easy operation of programmable LCD key switches which is a set of self-identical function keys that may be interfaced with any electronic modules/terminals from environmental and EMI/EMC while protecting the electronic module as well as keyboard assembly from the environmental and EMI/EMC and providing more visibility of LCDs.

BACKGROUND OF THE INVENTION:
The following background discussion includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication expressly or implicitly referenced is prior art.
Generally, it is known that interactive programmable interfaces for liquid crystal display (LCD) key switches are used as input devices for a wide variety of electronic equipment’s such as computers, tele communication devices, handheld terminals, mobile phones and many embedded systems or equipment’s. LCD key switches are generally used as single LCD key switch or an array of separate keys that are depressed by a user to interface with the electronic devices or equipment’s. The said electronic devices may undergo environmental challenges like rain, dust and other contaminants and EMI/EMC problems through the LCD key switches clearances gaps. It is difficult to protect the LCD keys of the electronics devices from the harsh environment and EMI/EMC interferences due to the many contours of the keys and the spaces between the keys.
Conventionally, it is known to provide a cover or an elastomeric boot to the keyboard that may restrict entry of contaminants into the interior of a keyboard. The conventional and existing keyboard covers are formed to match the contours of the keys but have significant inherent limitations. The conventional covers fail to provide protection to the keyboard from the harsh environment, EMI/EMC interferences and such conventional keyboard covers rigidly cover the entire keyboard assembly, but they do not allow for ease operation of the keyboard in the covered state and visibility of the LCD keys are very poor.
Presently available keyboard covers lack rugged mounting, allow contaminants like dust, water, insects etc. Further, such keypad covers fit loosely over the keyboard, and they easily fall off the keyboard. They may also be made of elastomeric material which lacks electrical conductivity, which will lead to EMI/EMC disturbance for the electronic modules used in harsh environmental conditions.
Accordingly, there exists a need to provide a protective cover to overcome one or more of the aforementioned problems.

OBJECTIVES OF THE INVENTION:
The primary object of the present invention is to overcome the problem stated in the prior art.
Another object of the present invention is to provide a protective cover assembly for a keyboard that is flexible and provide protection to electronic devices/equipment from environment and electromagnetic interfaces /electromagnetic compatibility (EMI/EMC).

SUMMARY OF THE INVENTION:
The present invention provides a protective cover assembly (1000) for a keyboard comprising:
a) an electronic module (100) having a plurality of LCD key switches from an EMI/EMC and environmental protection and ease LCD key;
b) a PCB assembly (200) with cable interface to an electronic processing PCB assembly (140);
c) atleast one front bezel (110) and at least one rear panel (150);
d) at least one mounting bracket (130) is configured to fix the electronic processing PCB assembly (140);
e) at least one EMI/EMC and environmental protective gasket (120) mounted on the least one front bezel (110);
wherein the front bezel (110) comprises at least one cut-out or hole (116) for receiving an LCD key switch passage in which LCD keys are visible to a user.
In an embodiment, the plurality of mounting holes (118) for fixing the rear panel (150) to the front bezel (110).
In an embodiment, the plurality of mounting holes (117) for mounting said at least one LCD key switch PCB assembly (200).
In an embodiment, the one gasket groove (114) for mounting/fixing/locating the at least one EMI/EMC and environmental protective gasket (120).
In an embodiment, the plurality of mounting holes (112) for mounting the flexible sandwiched substrate structure protective cover assembly (300).
In an embodiment, the plurality of mounting holes (119) for mounting/ fixing the electronic processing PCB assembly (140) or the mounting bracket (130).
In an embodiment, the rear panel (150) comprises a plurality of mounting holes (152) for mounting / fixing the rear panel (150) to the front bezel (110) and at least an internal cavity (155) to cover the electronic modules (100).
In an embodiment, the LCD Key switch PCB assembly (200) comprises at least one or a two-layer PCB blank (210) having a plurality of mounting holes (220) for mounting / fixing the PCB assembly (200) to the front bezel (110) using a plurality of fasteners (160), at least one LCD key switch (240) having a LCD screen (242).
In an embodiment, the electronic processing PCB (140) comprises at least one or a two-layer PCB blank (142) with processing PCB and other supporting components that interface with LCD key switch assembly (200) to get user input, a plurality of mounting holes (144) for fixing the processing PCB (140) to the mounting bracket (130) or directly fixed into the front bezel (110) through mounting hole by the plurality of fasteners (160).
The present invention provides a method of assembling the protective cover comprising the steps of:
a) assembling an electronic module (100) having an electronic processing PCB assembly (140) and a LCD key switch assembly (200) housed within a metal front and rear panel enclosure of the electronic module (100);
b) electrically connecting electronic processing PCB assembly (140) and a LCD key switch assembly (200) by using a cable (230) or a connector;
c) placing an environmental and EMI/EMC gasket (120) to a front bezel (110) for ensuring environmental and EMI/EMC protection between the matrix key frame assembly (300) and the electronic enclosure front bezel (110);
d) after completing assembly of LCD key switch PCB assembly 200 and electronic processing PCB 140 into the electrically conductive metal or non-metal with electrically conductive coated enclosure (110 & 150) and connecting with connector or cable (230) interfaces; and
e) assembling the matrix keypad frame assembly (300) with the sandwiched flexible shielding substrate (400, 500) to the front bezel by using fasteners (160, 380) to cover or close the gap or passage and contours between the LCD key switches (240) and the front bezel matrix (110) or array based frame assembly (300) by which the electrical conductivity and continuity to be ensure to protect from the EMI/EMC disturbances.

DETAILED DESCRIPTION OF DRAWINGS:
To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of their scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings in which:
Fig. 1: illustrates a front isometric exploded view of a protective cover for a LCD key switches assembly of an embedded electronic equipment.
Fig. 2: illustrates a rear isometric exploded view of the protective cover for a LCD key switches assembly of the embedded electronic equipment.
Fig. 3: illustrates a front isometric assembled view of a keypad frame with the protective cover.
Fig. 3A: illustrates a front isometric exploded view of the keypad frame with the protective cover.
Fig.3B: illustrates a front and sectional assembled view of the keypad frame with the protective cover.
Fig. 3C: illustrates a sectional assembled view of the keypad frame with the protective cover of Figure 3B.
Fig. 4: illustrates a front isometric exploded view of the assembly of the protective cover.
Fig. 4A: illustrates a rear isometric exploded view of the assembly of the protective cover.
Fig. 4B: illustrates an exploded view of the assembly of the protective cover with conductive adhesive.
Fig. 5: illustrates a front isometric exploded view of the assembly of the protective cover with conductive adhesive.
Fig. 5A: illustrates a rear isometric exploded view of the assembly of the protective cover with conductive adhesive.
Fig. 6: illustrates a front and rear isometric assembled view of the LCD key switch PCB assembly.

DETAILED DESCRIPTION:
For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof.
The terms “comprises”, “comprising”, “includes”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, device or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or device or method. In other words, one or more elements in a system or apparatus proceeded by “comprises... a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or method.
The present invention discloses a protective cover having a flexible sandwiched substrate structure that shields and provide protection for a keyboard and LCD keys from environmental and EMI/EMC. The protective cover completely shields all contours of the keys and any spaces between formed between the keys of an electronic equipment with interactive programmable interfaces for liquid crystal display (LCD) key switches.
Generally, a keyboard keys have contours and spaces that may allow the contaminants, such as water, dust and the like, pass into the interior of the keyboard. These contours and spaces may create or may observe EMI/EMC disturbances whereby the electronic equipment may fail to operate. Therefore, the present invention provides a protective cover that provides a protection shield to the contours of the keys and the spaces between the keys of the electronic equipment with the interactive programmable interfaces for liquid crystal display (LCD) key switches. The protective cover also enables that the "touch' or "feel' of the individual LCD keys of the matrix keyboard is retained when the flexible sandwiched substrate structure protective cover is in its operative position.
According to an exemplary embodiment, the flexible sandwiched substrate structure protective cover. The protective cover has an upper and lower housing and is designed for a keyboard assembly having a plurality of LCD key switches. The protective cover comprises a sandwiched overlay flexible membrane extending over a plurality of keys, where the sandwiched overlay flexible membrane is adaptable to allow the keys to be depressed through the sandwiched overlay flexible membrane. The protective cover also comprises a rigid frame attached to entire periphery of the sandwiched overlay flexible membrane.
In an embodiment, the present invention provides a protective cover assembly (1000) for a keyboard comprising:
a) an electronic module (100) having a plurality of LCD key switches from an EMI/EMC and environmental protection and ease LCD key;
b) a PCB assembly (200) with cable interface to an electronic processing PCB assembly (140);
c) atleast one front bezel (110) and at least one rear panel (150);
d) at least one mounting bracket (130) is configured to fix the electronic processing PCB assembly (140);
e) at least one EMI/EMC and environmental protective gasket (120) mounted on the least one front bezel (110);
wherein the front bezel (110) comprises at least one cut-out or hole (116) for receiving an LCD key switch passage in which LCD keys are visible to a user.
In an embodiment, the plurality of mounting holes (118) for fixing the rear panel (150) to the front bezel (110).
In an embodiment, the plurality of mounting holes (117) for mounting said at least one LCD key switch PCB assembly (200).
In an embodiment, the one gasket groove (114) for mounting/fixing/locating the at least one EMI/EMC and environmental protective gasket (120).
In an embodiment, the plurality of mounting holes (112) for mounting the flexible sandwiched substrate structure protective cover assembly (300).
In an embodiment, the plurality of mounting holes (119) for mounting/ fixing the electronic processing PCB assembly (140) or the mounting bracket (130).
In an embodiment, the rear panel (150) comprises a plurality of mounting holes (152) for mounting / fixing the rear panel (150) to the front bezel (110) and at least an internal cavity (155) to cover the electronic modules (100).
In an embodiment, the LCD Key switch PCB assembly (200) comprises at least one or a two-layer PCB blank (210) having a plurality of mounting holes (220) for mounting / fixing the PCB assembly (200) to the front bezel (110) using a plurality of fasteners (160), at least one LCD key switch (240) having a LCD screen (242).
In an embodiment, the electronic processing PCB (140) comprises at least one or a two-layer PCB blank (142) with processing PCB and other supporting components that interface with LCD key switch assembly (200) to get user input, a plurality of mounting holes (144) for fixing the processing PCB (140) to the mounting bracket (130) or directly fixed into the front bezel (110) through mounting hole by the plurality of fasteners (160).
In an embodiment, the present invention provides a method of assembling the protective cover comprising the steps of:
a) assembling an electronic module (100) having an electronic processing PCB assembly (140) and a LCD key switch assembly (200) housed within a metal front and rear panel enclosure of the electronic module (100);
b) electrically connecting electronic processing PCB assembly (140) and a LCD key switch assembly (200) by using a cable (230) or a connector;
c) placing an environmental and EMI/EMC gasket (120) to a front bezel (110) for ensuring environmental and EMI/EMC protection between the matrix key frame assembly (300) and the electronic enclosure front bezel (110);
d) after completing assembly of LCD key switch PCB assembly 200 and electronic processing PCB 140 into the electrically conductive metal or non-metal with electrically conductive coated enclosure (110 & 150) and connecting with connector or cable (230) interfaces; and
e) assembling the matrix keypad frame assembly (300) with the sandwiched flexible shielding substrate (400, 500) to the front bezel by using fasteners (160, 380) to cover or close the gap or passage and contours between the LCD key switches (240) and the front bezel matrix (110) or array based frame assembly (300) by which the electrical conductivity and continuity to be ensure to protect from the EMI/EMC disturbances.
Referring figures 1-6, according to an exemplary embodiment, the present invention discloses a protective cover assembly (1000) having a flexible substrate assembly that provides protection for an electronic module (100) having a plurality of LCD key switches from an EMI/EMC and environmental protection and ease LCD key switch operation between the user and the electronic module (100). The protective cover provides more visibility of the LCD screen with the plurality of LCD key switches.
According to an exemplary embodiment, the electronic module (100) comprises at least one LCD key switch PCB assembly (200) or a chassis mount LCD key switch assembly (alternate) with cable interface to an electronic processing PCB assembly (140). The electronic module (100) also comprises least one front bezel (110) and at least one rear panel (150). At least one mounting bracket (130) is configured to fix the electronic processing PCB assembly (140). The electronic module (100) further comprises at least one EMI/EMC and environmental protective gasket (120) mounted on the least one front bezel (110). The electronic module (100) further comprises a flexible sandwiched substrate structure protective cover assembly (300).
According to the exemplary embodiment of the present invention, the front bezel (110) comprises at least one cut-out or hole (116) for receiving a LCD key switch passage in which LCD keys are visible to a user, a plurality of mounting holes (118) for fixing the rear panel (150) to the front bezel (110), a plurality of mounting holes (117) for mounting said at least one LCD key switch PCB assembly (200), at least one gasket groove (114) for mounting/fixing/locating the at least one EMI/EMC and environmental protective gasket (120), a plurality of mounting holes (112) for mounting the flexible sandwiched substrate structure protective cover assembly (300), a plurality of mounting holes (119) for mounting/ fixing the electronic processing PCB assembly (140) or the mounting bracket (130).
According to the exemplary embodiment of the present invention, the rear panel (150) a plurality of mounting holes (152) for mounting / fixing the rear panel (150) to the front bezel (110) and at least an internal cavity (155) to cover the electronic modules (100).
According to the exemplary embodiment of the present invention, the LCD Key switch PCB assembly (200) comprises at least one or a two-layer PCB blank (210) having a plurality of mounting holes (220) for mounting / fixing the PCB assembly (200) to the front bezel (110) using a plurality of fasteners (160), at least one LCD key switch (240) having a LCD screen (242).
According to the exemplary embodiment of the present invention, the electronic processing PCB (140) comprises at least one or a two-layer PCB blank (142) with processing PCB and other supporting components that interface with LCD key switch assembly (200) to get user input, a plurality of mounting holes (144) for fixing the processing PCB (140) to the mounting bracket (130) or directly fixed into the front bezel (110) through mounting hole by the plurality of fasteners (160).
According to the exemplary embodiment of the present invention, the flexible sandwiched substrate structure protective cover assembly (300) comprises at least one electrically conductive metal support frame (320) or at least a non-metal frame with an electrically conductive coated support frame (320) having a plurality of mounting holes (322) for mounting / fixing an array shaped frame (360) and environmental protective gasket (340). The protective cover assembly (300) also comprises a recessed window area (324) for mounting a sandwiched flexible shielding substrate (400). The protective cover assembly (300) includes a plurality of mounting holes (326) for mounting / fixing the protective cover assembly (300) to the front bezel (110) mounting holes (112) by using plurality of fasteners (380).
According to the exemplary embodiment of the present invention, the sandwiched flexible shielding substrate (400) comprises at least one matrix or array shaped electrically conductive metal frame (410) or at least one non-metal with electrically conductive coated frame having at least one cut out (412) for receiving the LCD key switches of the LCD Key switch PCB assembly (200). The LCD Key switches are projected to user for interface. The sandwiched flexible shielding substrate (400) also comprises at least one conductive mesh (420) having customized cut by required profile (422) by keeping a minimum of 10 to 45-degree angle mesh (424) to ensure clear visibility of the LCD screen (242) of the LCD key switch (240) of the LCD Key switch PCB assembly (200), at least one flexible membrane (430) with at least one raised dome or projected shape profile (432). The raised dome or projected shape profile (432) is transparent to see the LCD screen (242) and provides better flexibility to press and depress the LCD key switch (240).
According to the exemplary embodiment of the present invention, the sandwiched flexible shielding substrate (400) further comprises at least one conductive adhesive thin sheet (440) with a cut profile (442) to see the LCD screen (242). The cut profile (442) of the at least one conductive adhesive thin sheet (440) is configured to mount / fix the conductive mesh (420) to the one surface frame (410) for ensuring an electrical continuity between frame (410) and the mesh (420). The sandwiched flexible shielding substrate (400) further comprises at least one non-conductive adhesive sheet (450) with a cut profile (452) to see the LCD screen (242). The cut profile (452) of the comprises at least one non-conductive adhesive sheet (450) is configured to mount / fix the conductive mesh (420) to the flexible membrane (430) rear surface for ensuring better flexibility and transparency.
According to another exemplary embodiment of the present invention, the sandwiched flexible shielding substrate (500) comprises at least one matrix or array shaped electrically conductive metal frame (510) or at least one non-metal with electrically conductive coated frame which having at least one cut out (512) for receiving the LCD key switches of the LCD Key switch PCB assembly (200). The LCD Key switches are projected to user for interface. The sandwiched flexible shielding substrate (500) further comprises at least one conductive mesh (520) having a customized cut by required profile (522) by keeping a minimum of 10 to 45-degree angle mesh (524) to ensure clear visibility of the LCD screen (242) of the LCD key switch (240) of the LCD Key switch PCB assembly (200), at least one flexible membrane (530) with at least one raised dome or projected shape profile (432). The raised dome or projected shape profile (432) is transparent to see the LCD screen (242) and provides better flexibility to press and depress the LCD key switch (240).
According to the exemplary embodiment of the present invention, the sandwiched flexible shielding substrate (500) further comprises at least one conductive adhesive thin sheet (540) with a cut profile (542) to see the LCD screen (242). The cut profile (542) of the at least one conductive adhesive thin sheet (540) is configured to mount / fix the conductive mesh (520) to the one surface frame (410) for ensuring an electrical continuity between frame (410) and the mesh (520). The sandwiched flexible shielding substrate (400) further comprises at least one non-conductive adhesive sheet (550) with a cut profile (552) to see the LCD screen (242). The cut profile (552) of the comprises at least one non-conductive adhesive sheet (550) is configured to mount / fix the conductive mesh (520) to the flexible membrane (530) rear surface for ensuring better flexibility and transparency. The flexible membrane (530) may be made by PC, acrylic or any other similar flexible material which may allow water, dust or other contaminants, to make more protection, at least one gasket (540) with self-adhesive.
According to the exemplary embodiment of the present invention, the at least one extruded environmental and EMC/EMC gasket (120) is cut as per length requirement.
According to another exemplary aspect, the present invention discloses a method of assembling the protective cover comprising the steps of assembling an electronic module (100) having an electronic processing PCB assembly (140) and a LCD key switch assembly (200) housed within a metal front and rear panel enclosure of the electronic module (100); electrically connecting electronic processing PCB assembly (140) and a LCD key switch assembly (200) by using a cable (230) or a connector; placing an environmental and EMI/EMC gasket (120) to a front bezel (110) for ensuring environmental and EMI/EMC protection between the matrix key frame assembly (300) and the electronic enclosure front bezel (110); after completing assembly of LCD key switch PCB assembly 200 and electronic processing PCB 140 into the electrically conductive metal or non-metal with electrically conductive coated enclosure (110 & 150) and connecting with connector or cable (230) interfaces; assembling the matrix keypad frame assembly (300) with the sandwiched flexible shielding substrate (400, 500) to the front bezel by using fasteners (160, 380) to cover or close the gap or passage and contours between the LCD key switches (240) and the front bezel matrix (110) or array based frame assembly (300) by which the electrical conductivity and continuity to be ensure to protect from the EMI/EMC disturbances.
According to the present invention, the protective cover (1000) ensures that the said electronic module (100) provides protection from the environmental to meet at least IP54 ingress protection rating and the electronic module (100)’s EMI/EMC compatibility will be ensured to meet MIL-461 E/F.
According to the exemplary embodiment, the present invention discloses a protective cover (1000) for an electronic module (100) comprising at least one metal or non-metal with/without metallic coated enclosure/housing to cover the electronic components such as processing PCB (140), LCD key switch PCB assembly (200) and to fix the matrix frame assembly (300); at least one electronic PCB (140) which need to get protected from the EMI/EMC disturbances, and same is assembled into an electronic metal enclosure; at least one LCD key switch PCB assembly which is assembled inside the electronic enclosure which need to be interfaced with processing PCB through cable or board to board connectors; and the same LCD key switch screen to be visible and to be operated by user; a sandwiched flexible EMI/EMC shield apparatus comprising; at least one electrically conductive metal frame or non-metal with electrically conductive metal coated frame, at least one electrically conductive mesh; at least one transparent flexible pad and conductive or nonconductive adhesive sheet; a matrix frame assembly comprising; at least one sandwiched flexible EMI/EMC shield apparatus; at least one matrix form or array based frame; at least one environmental gasket; and keypad support frame to fix the matrix frame assembly into the electronic enclosure; at least one EMI/EMC and environmental gasket which will have a contact with electronic module front bezel and the shielding apparatus frame assembly; at least one chassis mounts electrical connector which is mounted/assembled on electronic metal enclosure/chassis and electrically connected to the electronic processing PCB which is assembled inside of the electronic enclosure/chassis to provide power and other communication inputs.
According to the exemplary embodiment, the structural material of the electronic module enclosure, the walls of the front bezel and rear panel are made from at least one metal material selected from aluminum, copper, alloys, plastics thereof, and metal matrix composites or nonmetallic material with electrically conductive metal coated.
According to the exemplary embodiment, the electronic enclosure comprises one front bezel with mounting holes to fix the LCD key switch PCB assembly, electronic processing PCB, rear panel and the matrix or array based frame assembly.
According to the exemplary embodiment, the processing electronic PCB assembly comprises; one electronic processing PCB which will interface with power and other input and output signal by the user and other communication terminal and interface with LCD key switch PCB assembly to get input from the user; the said processing PCB is mounted on the front bezel or support frame by using fasteners.
According to the exemplary embodiment, the flexible sandwiched substrate structure protective cover assembly (300) at least one support frame to keep or hold the sandwiched flexible shielding substrate (400, 500) acting as environmental and EMI/EMC protection cover; at least one environmental gasket in which one surface will contact support frame surface and other surface will have contact with surface of matrix or array based frame; at least one the matrix or array based frame to rigidly press/fix the one sandwiched flexible EMI/EMC shield apparatus to ensure the electrical continuity of conductive mesh to protect unit from the EMI/EMC disturbances and to fix the environmental gasket to protect the contaminants such as water, dust and other similar particles.
According to the exemplary embodiment, the flexible sandwiched substrate structure protective cover assembly (300) with sandwiched flexible shielding substrate (400, 500) at least one electrically conductive metal frame or non-metal with electrically conductive metal coated frame, wherein the structural material of the metal frame, the walls & surface profiles are made from at least one material selected from aluminum, copper, alloys, or any other electrically conductive similar material in which conductive mesh will stuck by using conductive adhesive and riveted at two or three places and thereof; and same is manufactured by at least any one of milling, CNC milling or sheet metal fabrication or 3D Printing or any other similar manufacturing processes; at least one electrically conductive mesh which is stuck into the conductive metal frame by conductive adhesive and at least one portion of the conductive mesh is riveted to the conductive metal frame to ensure the better electrical conductivity and continuity; and said may manufactured through Monel or any similar electrical conductive materials; at least one transparent flexible pad including a raised or domed portion of the flexible pad used to provide better visibility of the individual LCD screen of LCD key switches; and same will be depressed during operation of LCD key switches; wherein the said structural material, the walls & surface profiles of the transparent flexible pad are made from at least one material selected from transparent rubber, PU, elastomeric material or any other similar flexible material and thereof; and same is manufactured by at least any one of injection moulding, vacuum forming, heat stacking or 3D Printing or any other similar manufacturing processes; at least one array shape conductive or nonconductive adhesive sheet; which is used to stick the conductive mesh to the conductive metal frame and stick the flexible transparent material to the conductive mesh.
According to the exemplary embodiment, the LCD key switch PCB (200) comprises at least one LCD key switch which is solder into the at least one/ 2-layer PCB with connector provision which will interface with the electronic processing PCB and assembled into enclosure by using fasteners.
According to the exemplary embodiment, the electronic enclosure chassis or connector mounting plate (910), wherein the structural material of the chassis, the walls & surface profiles are made from at least one material selected from aluminum, copper, alloys, or any other conductive similar material which is required a portion of surface area to masked during painting or non-conductive coatings and thereof; and is manufactured by at least any one of milling, CNC milling or sheet metal fabrication or 3D Printing or any other similar manufacturing processes.
According to the exemplary embodiment, the flexible sandwiched substrate structure protective cover assembly (300) with sandwiched flexible shielding substrate (400, 500) comprises electrically conductive mesh to be stick into the electrically conductive array shaped metal frame by using conductive adhesive and at least one spot, the conductive mesh to be riveted into the metal frame to ensure better electrical conductivity and continuity; at least one projected or domed shape transparent rubber, PU or similar material based flexible pad to be stuck into the conductive mesh by using conductive adhesive sheet.
According to the exemplary embodiment, the flexible sandwiched substrate structure protective cover assembly (300) with sandwiched flexible shielding substrate (400, 500) comprises electrically conductive mesh to be stick into the electrically conductive array shaped metal frame by using conductive adhesive and at least one spot, the conductive mesh to be riveted into the metal frame to ensure better electrical conductivity and continuity; at least one projected or domed shape transparent PC, acrylic or any similar material based flexible pad to be stuck into the conductive mesh by using conductive adhesive sheet; also environmental gasket to be stuck into top of transparent sheet to ensure environmental protection.
According to the exemplary embodiment, present invention discloses a reusable and ease replaceable environmental and EMI/EMC protection shield the for the electronic modules having at least one LCD key switch for user interface through sandwiched flexible EMI/EMC shield apparatus; the said environmental and EMI/EMC shield apparatus is replaced or reused by without dismantling the electronic module if required; as a single shielding apparatus, it will protect the electronic module from the EMI/EMC disturbances from other electronic modules and it will not allow EMI/EMC disturbances to the other electronic modules; it will protect the electronic module from the entry of contaminants such as water, dust and the like into the interior of the electronic module through the gap or passage and contours between the LCD key switches and the front bezel of the electronic module; the said shielding apparatus is a multilayer overlay assembly which comprises; a sandwiched flexible overlay membrane; matrix/array shaped metal frame; keypad support frame; electronic module with LCD key switch PCB assembly and metal or non-metal enclosure; and environmental and EMI/EMC gaskets; with this arrangement user gets better user experience to interface said electronic modules and also the said module will get protection from environmental and EMI/EMC disturbances.
The foregoing description of the invention has been set merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the substance of the invention may occur to person skilled in the art, the invention should be construed to include everything within the scope of the invention.

,CLAIMS:We Claim:

1. A protective cover assembly (1000) for a keyboard comprising:
a) an electronic module (100) having a plurality of LCD key switches from an EMI/EMC and environmental protection and ease LCD key;
b) a PCB assembly (200) with cable interface to an electronic processing PCB assembly (140);
c) atleast one front bezel (110) and at least one rear panel (150);
d) at least one mounting bracket (130) is configured to fix the electronic processing PCB assembly (140);
e) at least one EMI/EMC and environmental protective gasket (120) mounted on the least one front bezel (110);
wherein the front bezel (110) comprises at least one cut-out or hole (116) for receiving an LCD key switch passage in which LCD keys are visible to a user.
2. The protective cover assembly (1000) for a keyboard as claimed in claim 1, further comprises a plurality of mounting holes (118) for fixing the rear panel (150) to the front bezel (110).
3. The protective cover assembly (1000) for a keyboard as claimed in claim 1, further comprises a plurality of mounting holes (117) for mounting said at least one LCD key switch PCB assembly (200).
4. The protective cover assembly (1000) for a keyboard as claimed in claim 1, comprises at least one gasket groove (114) for mounting/fixing/locating the at least one EMI/EMC and environmental protective gasket (120).
5. The protective cover assembly (1000) for a keyboard as claimed in claim 1 comprises a plurality of mounting holes (112) for mounting the flexible sandwiched substrate structure protective cover assembly (300).
6. The protective cover assembly (1000) for a keyboard as claimed in claim 1 comprises a plurality of mounting holes (119) for mounting/ fixing the electronic processing PCB assembly (140) or the mounting bracket (130).
7. The protective cover assembly (1000) for a keyboard as claimed in claim 1 wherein the rear panel (150) comprises a plurality of mounting holes (152) for mounting / fixing the rear panel (150) to the front bezel (110) and at least an internal cavity (155) to cover the electronic modules (100).
8. The protective cover assembly (1000) for a keyboard as claimed in claim 1 wherein the LCD Key switch PCB assembly (200) comprises at least one or a two-layer PCB blank (210) having a plurality of mounting holes (220) for mounting / fixing the PCB assembly (200) to the front bezel (110) using a plurality of fasteners (160), at least one LCD key switch (240) having a LCD screen (242).
9. The protective cover assembly (1000) for a keyboard as claimed in claim 1 wherein the electronic processing PCB (140) comprises at least one or a two-layer PCB blank (142) with processing PCB and other supporting components that interface with LCD key switch assembly (200) to get user input, a plurality of mounting holes (144) for fixing the processing PCB (140) to the mounting bracket (130) or directly fixed into the front bezel (110) through mounting hole by the plurality of fasteners (160).
10. A method of assembling the protective cover comprising the steps of:
a) assembling an electronic module (100) having an electronic processing PCB assembly (140) and a LCD key switch assembly (200) housed within a metal front and rear panel enclosure of the electronic module (100);
b) electrically connecting electronic processing PCB assembly (140) and a LCD key switch assembly (200) by using a cable (230) or a connector;
c) placing an environmental and EMI/EMC gasket (120) to a front bezel (110) for ensuring environmental and EMI/EMC protection between the matrix key frame assembly (300) and the electronic enclosure front bezel (110);
d) after completing assembly of LCD key switch PCB assembly 200 and electronic processing PCB 140 into the electrically conductive metal or non-metal with electrically conductive coated enclosure (110 & 150) and connecting with connector or cable (230) interfaces; and
e) assembling the matrix keypad frame assembly (300) with the sandwiched flexible shielding substrate (400, 500) to the front bezel by using fasteners (160, 380) to cover or close the gap or passage and contours between the LCD key switches (240) and the front bezel matrix (110) or array based frame assembly (300) by which the electrical conductivity and continuity to be ensure to protect from the EMI/EMC disturbances.