Systems and methods for lighting spring loaded mechanical key switches

• US 9,368,300 B2
• Filed: 08/29/2013
• Issued: 06/14/2016
• Est. Priority Date: 08/29/2013
• Status: Active Grant

• Current Assignee: Dell Products LP (Dell Technologies Inc.)
• Original Assignee: Dell Products LP (Dell Technologies Inc.)
• Inventors: Casparian, Mark A., Azor, Frank C., Olmsted, Joe A.
• Primary Examiner(s): Lim, Steven
• Assistant Examiner(s): Haile, Benyam
• Application Number:
  US14/013,603
• Publication Number:
  US 20150061901A1
• Time in Patent Office: 1,020 Days
• Field of Search: 341/34
• US Class Current: 1/1
• CPC Class Codes: G02B 1/045 Light guides
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• CPC Class Codes: G02B 6/0025 Diffusing sheet or layer; Prismatic sheet or layer
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G02B 6/3596 With planar waveguide arrangement, i.e. in a substrate, regardless if actuating mechanism is outside the substrate
• CPC Class Codes: G06F 3/0202 Constructional details or processes of manufacture of the input device
• CPC Class Codes: G06F 3/0219 Special purpose keyboards
• CPC Class Codes: G06F 3/023 Arrangements for converting discrete items of information into a coded form, e.g. arrangements for interpreting keyboard generated codes as alphanumeric codes, operand codes or instruction codes
• CPC Class Codes: H01H 13/28 using compression or extension of coil springs
• CPC Class Codes: H01H 13/52 the contact returning to its original state immediately upon removal of operating force, e.g. bell-push switch
• CPC Class Codes: H01H 13/70 having a plurality of operating members associated with different sets of contacts, e.g. keyboard mounting together a plurality of independent switches H02B
• CPC Class Codes: H01H 13/705 characterised by construction, mounting or arrangement of operating parts, e.g. push-buttons or keys
• CPC Class Codes: H01H 13/83 characterised by legends, e.g. Braille, liquid crystal displays, light emitting or optical elements
• CPC Class Codes: H01H 2219/014 LED
• CPC Class Codes: H01H 2219/028 Printed information
• CPC Class Codes: H01H 2219/036 Light emitting elements
• CPC Class Codes: H01H 2219/044 Edge lighting of layer
• CPC Class Codes: H01H 2219/06 Reflector
• CPC Class Codes: H01H 2219/062 Light conductor
• CPC Class Codes: H01H 2219/0621 Optical fiber light conductor
• CPC Class Codes: H01H 9/182 : Illumination of the symbols or distinguishing marks H01H9/181 takes precedence

Abstract

Systems and methods are disclosed that may be implemented to provide keycap lighting to a spring loaded mechanical key switch assembly using a light conductive structure, such as a light pipe, and without requiring a chassis housing of the mechanical key switch assembly to include a dedicated power-consuming light source mounted to or otherwise positioned at the location of the individual key switch assembly chassis housing. Additionally, the disclosed systems and methods may be implemented to use one or more common power-consuming light source/s to simultaneously provide key cap lighting to multiple such spring loaded mechanical key switch assemblies, for example, by feeding light to each key cap though a common light spreader and through an individual non-power consuming light pipe provided for each key switch assembly.

Claims

1. A keyboard system, comprising:

a light spreader component comprised of light transmissive material;

one or more light sources positioned to direct light into the light transmissive material of the light spreader component; and

at least one spring loaded mechanical key switch assembly comprising;

a key switch chassis housing having a first end and a second end,

a downwardly depressible key component movably received within the key switch chassis housing and having a first end and a second end, the first end of the depressible key component being linearly movable downward between an extended position and a depressed position relative to the first end of the key switch chassis housing with the first end of the depressible key component being closer to the first end of the key switch chassis housing in the depressed position than in the extended position,

a spring element configured to provide a resilient force to resist downward movement of the depressible key component from the extended position to the depressed position,

at least one of digital signal circuitry configured to provide an on/off digital output signal when the depressible key component is depressed downward by a predetermined extent, variable displacement-sensing circuitry configured to detect downward linear displacement of the depressible key component relative to the key switch chassis housing and to provide one or more variable displacement signals that vary in character based on the amount of linear displacement of the depressible key component between the extended position and the depressed position, or a combination thereof, and

at least one light conductive structure having first and second ends and extending upward from the second end of the key switch chassis housing to the first end of the key switch chassis housing, the first end of the light conductive structure being positioned adjacent the first end of the key switch chassis housing and the second end of the light conductive structure being positioned adjacent the second end of the key switch chassis housing;

where a second end of the light conductive structure is positioned to receive light from the light spreader component;

where the light conductive structure is configured to conduct light received from the light spreader upward to the first end of the light conductive structure; and

where the first end of the light conductive structure is configured to emit the conducted light upward from the first end of the light conductive structure; and

where the depressible key component further comprises a keycap on the first end of the depressible key component;

where the light conductive structure comprises a light pipe extending upward in adjacent side by side relationship with the downwardly depressible key component;

where the keycap comprises a top surface and an underside surface opposite the top surface, the underside surface of the keycap facing the first end of the light conductive structure to receive the light emitted therefrom, and the top surface of the keycap facing upward toward a user of the keyboard system; and

where the keycap further comprises one or more light transmissive features extending through the keycap from the underside surface to the top surface of the keycap such that light emitted from beneath the key cap by the light conductive structure is visible by a user of the keyboard system from above the key cap through the light transmissive key features.

2. The system of claim 1, where the light transmissive features comprise at least one of a laser etched alphanumeric character, a laser etched key cap rim, an aperture defined in the keycap, a transparent or translucent keycap material, or a combination thereof.

3. The system of claim 1, where the at least one spring loaded mechanical key switch assembly comprises multiple such spring loaded mechanical key switch assemblies;

where the light spreader is a planar light spreader component;

where each of the light conductive structures extends upward from a planar side of the planar light structure; and

where a second end of the light conductive structure of each of the multiple spring loaded mechanical key switch assemblies is positioned to receive light from the same planar light spreader component as is the second end of the light conductive structure of each of the other multiple spring loaded mechanical key switch assemblies.

4. The system of claim 1, comprising digital signal circuitry configured to provide an on/off digital output signal when the depressible key component is depressed downward by a predetermined extent.

5. An information handling system including the keyboard assembly of claim 4, comprising:

at least one host processing device configured to execute a user application thereon; and

a keyboard assembly according to claim 4;

where the keyboard controller is configured to process the on/off digital output signal and to provide the processed digital key information based on the on/off digital output signal to the host processing device.

6. The system of claim 1, comprising variable displacement-sensing circuitry configured to detect displacement of the depressible key component relative to the key switch chassis housing and to provide one or more variable displacement signals that vary in character based on the amount of linear displacement of the depressible key component between the extended position and the depressed position, or a combination thereof.

7. The system of claim 1, comprising each of digital signal circuitry configured to provide an on/off digital output signal when the depressible key component is depressed downward by a predetermined extent;

and variable displacement-sensing circuitry configured to detect displacement of the depressible key component relative to the key switch chassis housing and to provide one or more variable displacement signals that vary in character based on the amount of linear displacement of the depressible key component between the extended position and the depressed position, or a combination thereof.

8. The system of claim 1, where the depressible key component is linearly movable downward and upward along a single axis;

and where the light conductive structure comprises a light pipe extending upward in adjacent parallel relationship with the axis of the downwardly depressible key component.

9. The system of claim 1, where the second end of the depressible key component is closer to the second end of the depressible key switch housing when the key component is in the extended position than when the depressible key component is in the depressed position.

10. A keyboard system, comprising:

a light spreader component comprised of light transmissive material;

one or more light sources positioned to direct light into the light transmissive material of the light spreader component; and

at least one spring loaded mechanical key switch assembly comprising;

a key switch chassis housing having a first end and a second end,

a downwardly depressible key component movably received within the key switch chassis housing and having a first end and a second end, the first end of the depressible key component being linearly movable downward between an extended position and a depressed position relative to the first end of the key switch chassis housing with the first end of the depressible key component being closer to the first end of the key switch chassis housing in the depressed position than in the extended position,

a spring element configured to provide a resilient force to resist downward movement of the depressible key component from the extended position to the depressed position,

at least one of digital signal circuitry configured to provide an on/off digital output signal when the depressible key component is depressed downward by a predetermined extent, variable displacement-sensing circuitry configured to detect downward linear displacement of the depressible key component relative to the key switch chassis housing and to provide one or more variable displacement signals that vary in character based on the amount of linear displacement of the depressible key component between the extended position and the depressed position, or a combination thereof, and

at least one light conductive structure having first and second ends and extending upward from the second end of the key switch chassis housing to the first end of the key switch chassis housing, the first end of the light conductive structure being positioned adjacent the first end of the key switch chassis housing and the second end of the light conductive structure being positioned adjacent the second end of the key switch chassis housing;

where a second end of the light conductive structure is positioned to receive light from the light spreader component;

where the light conductive structure is configured to conduct light received from the light spreader upward to the first end of the light conductive structure; and

where the first end of the light conductive structure is configured to emit the conducted light upward from the first end of the light conductive structure; and

where the light spreader is a substantially planar light spreader component; and

where the system further comprises;

a substantially planar printed circuit board (PCB) disposed between the first end of the key switch chassis housing and the light spreader component with a plane of the PCB being oriented in substantially parallel relationship with a plane of the light spreader component, and with a first opening being defined to extend through the PCB that is dimensionally configured to receive the light conductive structure therein, and

where the light conductive structure extends from the key switch chassis housing through the first opening defined in the PCB such that the second end of the light conductive structure is positioned between the PCB and the light spreader component in a position adjacent to the light spreader component to receive the light from the light spreader component.

11. The system of claim 10, further comprising a substantially planar light reflective film having a plane oriented in substantially parallel relationship with a plane of the light spreader component, the light spreader component being disposed between the PCB and the light reflective film.

12. A keyboard system, comprising:

a light spreader component comprised of light transmissive material;

one or more light sources positioned to direct light into the light transmissive material of the light spreader component; and

at least one spring loaded mechanical key switch assembly comprising;

a key switch chassis housing having a first end and a second end,

a depressible key component movably received within the key switch chassis housing and having a first end and a second end, the first end of the depressible key component being movable between an extended position and a depressed position relative to the first end of the key switch chassis housing with the first end of the depressible key component being closer to the first end of the key switch chassis housing in the depressed position than in the extended position,

a spring element configured to provide a resilient force to resist downward movement of the depressible key component from the extended position to the depressed position,

at least one of digital signal circuitry configured to provide an on/off digital output signal when the depressible key component is depressed downward by a predetermined extent, variable displacement-sensing circuitry configured to detect downward linear displacement of the depressible key component relative to the key switch chassis housing and to provide one or more variable displacement signals that vary in character based on the amount of linear displacement of the depressible key component between the extended position and the depressed position, or a combination thereof, and

at least one light conductive structure having first and second ends and extending upward from the second end of the key switch chassis housing to the first end of the key switch chassis housing, the first end of the light conductive structure being positioned adjacent the first end of the key switch chassis housing and the second end of the light conductive structure being positioned adjacent the second end of the key switch chassis housing;

where a second end of the light conductive structure is positioned to receive light from the light spreader component;

where the light conductive structure is configured to conduct light received from the light spreader upward to the first end of the light conductive structure; and

where the first end of the light conductive structure is configured to emit the conducted light upward from the first end of the light conductive structure;

where the light spreader is a substantially planar light spreader component; and

where the system further comprises;

a substantially planar printed circuit board (PCB) disposed between the first end of the key switch chassis housing and the light spreader component with a plane of the PCB being oriented in substantially parallel relationship with a plane of the light spreader component, and with a first opening being defined to extend through the PCB that is dimensionally configured to receive the light conductive structure therein, and

where the light conductive structure extends from the key switch chassis housing through the first opening defined in the PCB such that the second end of the light conductive structure is positioned between the PCB and the light spreader component in a position adjacent to the light spreader component to receive the light from the light spreader component, and

where a second opening is defined to extend through the PCB adjacent to the first opening; and

where the key switch assembly further comprises a mounting guide that is dimensionally configured to be received within the second opening, the mounting guide being assembled into the second opening to mount the key switch assembly to the PCB with the light conductive structure extending from the key switch chassis housing through the first opening defined in the PCB.

13. The system of claim 12, where the at least one spring loaded mechanical key switch assembly comprises multiple such spring loaded mechanical key switch assemblies;

where multiple adjacent first and second openings corresponding to the multiple key switch assemblies are defined to extend through the PCB; and

where each of the given multiple key switch assemblies further comprises a mounting guide that is assembled into a respective second opening to mount the given key switch assembly to the PCB with the light conductive structure of the given key switch assembly extending from the key switch chassis housing through a respective first opening defined in the PCB adjacent to the respective second opening.

14. A spring loaded mechanical key switch assembly, comprising:

a key switch chassis housing having a first end and a second end;

1

a downwardly depressible key component movably received within the key switch chassis housing and having a first end and a second end, the first end of the depressible key component being linearly movable downward between an extended position and a depressed position relative to the first end of the key switch chassis housing with the first end of the depressible key component being closer to the first end of the key switch chassis housing in the depressed position than in the extended position;

a spring element configured to provide a resilient force to resist downward movement of the depressible key component from the extended position to the depressed position;

at least one of digital signal circuitry configured to provide an on/off digital output signal when the depressible key component is depressed downward by a predetermined extent, variable displacement-sensing circuitry configured to detect downward linear displacement of the depressible key component relative to the key switch chassis housing and to provide one or more variable displacement signals that vary in character based on the amount of linear displacement of the depressible key component between the extended position and the depressed position, or a combination thereof, and

at least one light conductive structure having first and second ends and extending upward from the second end of the key switch chassis housing to the first end of the key switch chassis housing, the first end of the light conductive structure being positioned adjacent the first end of the key switch chassis housing and the second end of the light conductive structure being positioned adjacent the second end of the key switch chassis housing;

where a second end of the light conductive structure is positioned to receive light from a light spreader component;

where the light conductive structure is configured to conduct light received from the light spreader upward to the first end of the light conductive structure;

where the first end of the light conductive structure is configured to emit the conducted light upward from the first end of the light conductive structure; and

where the depressible key component further comprises a keycap on the first end of the depressible key component;

where the light conductive structure comprises a light pipe extending upward in adjacent side by side relationship with the downwardly depressible key component; and

where the keycap comprises a top surface and an underside surface opposite the top surface, the underside surface of the keycap facing the first end of the light conductive structure to receive the light emitted therefrom, and the top surface of the keycap facing upward toward a user;

where the keycap further comprises one or more light transmissive features extending through the keycap from the underside surface to the top surface of the keycap such that light emitted from beneath the key cap by the light conductive structure is visible by a user from above the key cap through the light transmissive key features.

15. The key switch assembly of claim 14, where the light transmissive features comprise at least one of a laser etched alphanumeric character, a laser etched key cap rim, an aperture defined in the keycap, a transparent or translucent keycap material, or a combination thereof.

16. The key switch assembly of claim 14, comprising digital signal circuitry configured to provide an on/off digital output signal when the depressible key component is depressed downward by a predetermined extent.

17. The key switch assembly of claim 14, comprising variable displacement-sensing circuitry configured to detect displacement of the depressible key component relative to the key switch chassis housing and to provide one or more variable displacement signals that vary in character based on the amount of linear displacement of the depressible key component between the extended position and the depressed position, or a combination thereof.

18. The key switch assembly of claim 14, comprising each of digital signal circuitry configured to provide an on/off digital output signal when the depressible key component is depressed downward by a predetermined extent;

and variable displacement-sensing circuitry configured to detect displacement of the depressible key component relative to the key switch chassis housing and to provide one or more variable displacement signals that vary in character based on the amount of linear displacement of the depressible key component between the extended position and the depressed position, or a combination thereof.

19. The key switch assembly of claim 14, where the depressible key component is linearly movable downward and upward along a single axis;

and

where the light conductive structure comprises a light pipe extending upward in adjacent parallel relationship with the axis of the downwardly depressible key component.

20. The key switch assembly of claim 14, where the second end of the depressible key component is closer to the second end of the key switch housing when the depressible key component is in the extended position than when the depressible key component is in the depressed position.

21. A method of operating one or more key switch assemblies, comprising:

providing at least one spring loaded mechanical key switch assembly, comprising;

a key switch chassis housing having a first end and a second end,

a downwardly depressible key component movably received within the key switch chassis housing and having a first end and a second end, the first end of the depressible key component being linearly movable downward between an extended position and a depressed position relative to the first end of the key switch chassis housing with the first end of the depressible key component being closer to the first end of the key switch chassis housing in the depressed position than in the extended position,

a spring element configured to provide a resilient force to resist downward movement of the depressible key component from the extended position to the depressed position,

at least one of digital signal circuitry configured to provide an on/off digital output signal when the depressible key component is depressed downward by a predetermined extent, variable displacement-sensing circuitry configured to detect downward linear displacement of the depressible key component relative to the key switch chassis housing and to provide one or more variable displacement signals that vary in character based on the amount of linear displacement of the depressible key component between the extended position and the depressed position, or a combination thereof, and

at least one light conductive structure having first and second ends and extending upward from the second end of the key switch chassis housing to the first end of the key switch chassis housing, the first end of the light conductive structure being positioned adjacent the first end of the key switch chassis housing and the second end of the light conductive structure being positioned adjacent the second end of the key switch chassis housing, the light conductive structure being configured to conduct light upward from the second end to the first end of the light conductive structure,

where the first end of the light conductive structure is configured to emit the conducted light from the first end of the light conductive structure; and

providing light to the second end of the light conductive structure to cause the light conductive structure to conduct and emit the light upward from the first end of the light conductive structure;

where the depressible key component further comprises a keycap on the first end of the depressible key component;

where the light conductive structure comprises a light pipe extending upward in adjacent side by side relationship with the downwardly depressible key component;

where the keycap comprises a top surface and an underside surface opposite the top surface, the underside surface of the keycap facing the first end of the light conductive structure to receive the light emitted therefrom, and the top surface of the keycap facing upward toward a user;

where the keycap further comprises one or more light transmissive features extending through the keycap from the underside surface to the top surface of the keycap such that light emitted from beneath the key cap by the light conductive structure is visible by a user from above the key cap through the light transmissive key features.

22. The method of operating one or more key switch assemblies of claim 21, further comprising:

providing multiple spring loaded mechanical key switch assemblies; and

providing light to the respective second end of the light conductive structure of each of the multiple spring loaded mechanical key assemblies using at least one common light source to cause the light conductive structure of each the multiple mechanical key switch assemblies to conduct and emit the light from the respective first end of the light conductive structure of each of the multiple spring loaded mechanical key assemblies.

23. The method of operating one or more key switch assemblies of claim 21, where the depressible key component is linearly movable downward and upward along a single axis;

and where the light conductive structure comprises a light pipe extending upward in adjacent parallel relationship with the axis of the downwardly depressible key component.

24. The method of operating one or more key switch assemblies of claim 21, where the second end of the depressible key component is closer to the second end of the key switch housing when the depressible key component is in the extended position than when the depressible key component is in the depressed position.