# US 2020/0402736 A1 · Key structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0402736 A1 - Document ID: US20200402736A1 - Status: Published application - Kind: A1 - Application number: 16/904,575 - Filed: 2020-06-18 - Published: 2020-12-24 - Earliest claimed: 2019-06-18 - Assignees: Lite-On Electronics (Guangzhou) Limited; Lite-On Technology Corporation - Applicants: Lite-On Electronics (Guangzhou) Limited; Lite-On Technology Corporation - Inventors: Kuo-Hui Hsu; Cheng-Kun Liao; Li-Sheng Hsiao; En-Huei Wang - Web page: https://patentgrep.com/patent/US20200402736A1 ## CPC - G02B 6/0021: {for housing at least a part of the light source, e.g. by forming holes or recesses} - G02B 6/0031: {Reflecting element, sheet or layer} - G02B 6/0036: {2-D arrangement of prisms, protrusions, indentations or roughened surfaces} - G02B 6/0055: {Reflecting element, sheet or layer} - G06F 3/0202: {Constructional details or processes of manufacture of the input device} - H01H 3/125: {using a scissor mechanism as stabiliser} - H01H 13/14: Operating parts, e.g. push-button - H01H 13/704: characterised by the layers, e.g. by their material or structure (H01H13/703 takes precedence) - H01H 13/705: characterised by construction, mounting or arrangement of operating parts, e.g. push-buttons or keys - H01H 13/7057: characterised by the arrangement of operating parts in relation to each other, e.g. pre-assembled groups of keys - H01H 13/785: characterised by the material of the contacts, e.g. conductive polymers - H01H 13/83: characterised by legends, e.g. Braille, liquid crystal displays, light emitting or optical elements - G02B 6/0073: {Light emitting diode [LED]} - G02B 6/0088: {of the light guide or other optical sheets in the package} - G02B 6/009: {of the light source in the package (G02B6/0021 takes precedence)} - G02B 6/0091: {of the light source relative to the light guide (G02B6/0021 takes precedence)} - H01H 2203/052: for backlighted keyboards - H01H 2219/039: Selective or different modes of illumination - H01H 2219/056: Diffuser; Uneven surface - H01H 2219/06: Reflector - H01H 2219/062: Light conductor - H01H 2221/058: to avoid tilting or skewing of contact area or actuator - H01H 2221/066: replaceable - H01H 2229/044: Injection moulding - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) ## Abstract A key structure includes a keycap, a connection assembly, engaging members, and a base plate. The connection assembly disposed between the base plate and the keycap is movably connected to the keycap and the engaging members, so that the keycap and the connection assembly engaged with the engaging members are positioned on the base plate. The base plate includes engaging protrusions protruding from an upper surface, so that the engaging members are bonded to the base plate through the engaging protrusions. Each engaging protrusion is located between two openings of the base plate, connects the two openings, or is disposed corresponding to the openings. Each engaging member covers one or more engaging protrusions through injection molding, and is fixed to the base plate. The engaging members are respectively disposed on the openings, fill the openings, or completely cover the engaging protrusions. ## Claims ### Claim 1 A key structure, comprising: a base plate, having an upper surface, a lower surface opposite to the upper surface, a first opening, a second opening, and a third opening, and comprising a first engaging protrusion and a second engaging protrusion that are respectively extended from the upper surface, wherein the first engaging protrusion is located between the first opening and the second opening, and the second engaging protrusion is located between the second opening and the third opening; a first engaging member, covering the first engaging protrusion and the second engaging protrusion through injection molding, and being coupled to the first opening, the second opening, and the third opening; a keycap, disposed above the base plate; and a connection assembly, disposed between the base plate and the keycap, wherein one end of the connection assembly is movably connected to the keycap, and the other end of the connection assembly is movably connected to the first engaging member, so that the keycap is adapted to move up and down relative to the base plate with the connection assembly. ### Claim 2 (depends on 1) The key structure according to claim 1, wherein the first opening and the second opening communicate with each other through the first engaging protrusion, the second opening and the third opening communicate with each other through the second engaging protrusion, and the first engaging protrusion and the second engaging protrusion are obliquely aligned with an axis. ### Claim 3 (depends on 2) The key structure according to claim 2, wherein a bottom surface of the first engaging member is aligned with the lower surface of the base plate. ### Claim 4 (depends on 3) The key structure according to claim 3, further comprising: a second engaging member, a third engaging member, and a fourth engaging member, the base plate further having a plurality of openings and comprising a plurality of engaging protrusions, wherein the second engaging member covers at least two of the engaging protrusions through injection molding, the first engaging member and the second engaging member include two first engaging portions, the third engaging member and the fourth engaging member respectively cover one of the engaging protrusions through injection molding and include two second engaging portions, the connection assembly is pivotally connected to the two first engaging portions and the two second engaging portions respectively, and the second engaging member, the third engaging member, and the fourth engaging member are coupled to the corresponding openings of the base plate. ### Claim 5 (depends on 3) The key structure according to claim 3, further comprising: a second engaging member, a third engaging member, and a fourth engaging member, wherein the first engaging member and the second engaging member are respectively provided with two first engaging portions through injection molding, the third engaging member and the fourth engaging member are respectively provided with two second engaging portions through injection molding, the connection assembly comprises a first supporting member and a second supporting member pivotally connected with each other, the first supporting member is located at an outer side of the second supporting member, a first end of the first supporting member is pivotally connected to the two first engaging portions, a second end of the first supporting member is pivotally connected to the keycap, a first end of the second supporting member is pivotally connected to the two second engaging portions, a second end of the second supporting member is pivotally connected to the keycap, the first end of the first supporting member of the connection assembly is rotatably arranged within the two first engaging portions, and the first end of the second supporting member is slidably arranged within the two second engaging portions. ### Claim 6 (depends on 4) The key structure according to claim 4, wherein at least one of the first engaging portions is a retaining groove, and at least one of the second engaging portions is a retaining hook. ### Claim 7 (depends on 1) The key structure according to claim 1, further comprising: a membrane circuit board, disposed between the keycap and the base plate, wherein the membrane circuit board has a plurality of through holes exposing the first engaging member and a part of the base plate. ### Claim 8 (depends on 7) The key structure according to claim 7, further comprising: an elastic component, positioned within an aperture confined by the connection assembly and disposed between the keycap and the membrane circuit board. ### Claim 9 A key structure, comprising: a base plate, having a plurality of openings, an upper surface, and a lower surface opposite to the upper surface, and comprising a plurality of engaging protrusions protruding from the upper surface, wherein each of the engaging protrusions is located between two of the openings, and the two openings communicate with each other through an accommodation under each of the engaging protrusions; a first engaging member, a second engaging member, a third engaging member, and a fourth engaging member, wherein the first engaging member and the second engaging member respectively cover at least two of the engaging protrusions through injection molding, and the third engaging member and the fourth engaging member respectively cover one of the engaging protrusions through injection molding; a keycap, disposed above the base plate; and a connection assembly, disposed between the base plate and the keycap and having a first supporting member and a second supporting member pivotally connected to each other, wherein the first supporting member is located at an outer side of the second supporting member, a first end of the first supporting member is pivotally connected to the first engaging member and the second engaging member, a second end of the first supporting member is pivotally connected to the keycap, a first end of the second supporting member is pivotally connected to the third engaging member and the fourth engaging member, and a second end of the second supporting member is pivotally connected to the keycap, so that the keycap is adapted to move up and down relative to the base plate with the connection assembly. ### Claim 10 (depends on 9) The key structure according to claim 9, wherein the at least two of the engaging protrusions respectively covered by the first engaging member and the second engaging member are obliquely aligned with an axis passing through the openings. ### Claim 11 (depends on 10) The key structure according to claim 10, wherein a bottom surface of each of the first engaging member, the second engaging member, the third engaging member, and the fourth engaging member is aligned with the lower surface of the base plate. ### Claim 12 (depends on 11) The key structure according to claim 11, wherein the first engaging member and the second engaging member respectively have first engaging portions, the third engaging member and the fourth engaging member respectively have second engaging portions, and the connection assembly is pivotally connected to the first engaging portions and the second engaging portions. ### Claim 13 (depends on 12) The key structure according to claim 12, wherein at least one of the first engaging portions is a retaining groove, at least one of the second engaging portions is a retaining hook, so that the first end of the first supporting member of the connection assembly is rotatably positioned in the retaining groove, and the first end of the second supporting member is slidably positioned in the retaining hook. ### Claim 14 (depends on 9) The key structure according to claim 9, wherein further comprising: a membrane circuit board, disposed between the keycap and the base plate, wherein the membrane circuit board has a plurality of through holes exposing the first engaging member, the second engaging member, the third engaging member, the fourth engaging member, and a part of the base plate; and an elastic component, passing through the connection assembly and disposed between the keycap and the membrane circuit board. ### Claim 15 (depends on 9) The key structure according to claim 9, wherein any one of the engaging protrusions has a top surface and a bottom surface opposite to each other, and a contour of the bottom surface is different from a contour of the top surface. ### Claim 16 (depends on 9) The key structure according to claim 9, wherein a shape of any one of the engaging protrusions comprises an arch-shaped structure, a bridge-shaped structure, an arch- or bridge-shaped structure with a hole, or a divided arch- or bridge-shaped structure with disconnected protrusions. ### Claim 17 A key structure, comprising: a base plate, having an upper surface, a lower surface opposite to the upper surface, a first opening, and a second opening, and comprising a first engaging protrusion extended from the upper surface, wherein the first engaging protrusion is located between the first opening and the second opening, and a width of the first engaging protrusion is smaller than a width of the first opening or the second opening; a first engaging member, positioned in the first opening and the second opening, and covering a top surface and a bottom surface of the first engaging protrusion; a keycap, disposed above the base plate; and a connection assembly, disposed between the base plate and the keycap, wherein one end of the connection assembly is movably connected to the keycap, and the other end of the connection assembly is movably connected to the first engaging member. ### Claim 18 (depends on 17) The key structure according to claim 17, wherein the base plate further has a third opening and comprises a second engaging protrusion extended from the upper surface, wherein the second engaging protrusion is located between the second opening and the third opening, and the first engaging member is integrally positioned in the third opening and covers the second engaging protrusion. ### Claim 19 (depends on 18) The key structure according to claim 18, wherein the first engaging protrusion and the second engaging protrusion are in an off-centered alignment. ### Claim 20 (depends on 17) The key structure according to claim 17, wherein one of the top surface and the bottom surface of the first engaging protrusion comprises a beveled edge, a chamfered edge, or a rounded edge. ### Claim 21 (depends on 17) The key structure according to claim 17, wherein the first engaging member has a first engaging portion with a retaining interface for coupling the connection assembly.