ILLUMINATED KEY-PAD ASSEMBLY

• US 20090107816A1
• Filed: 10/29/2007
• Published: 04/30/2009
• Est. Priority Date: 10/29/2007
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Penner, Dennis James, Kyowski, Timothy Herbert, CHEN, Chao Carl
• Granted Patent: US 7,671,290 B2
• Time in Patent Office: Days
• US Class Current: 200/314
• CPC Class Codes: H01H 13/83 characterised by legends, e.g. Braille, liquid crystal displays, light emitting or optical elements
• CPC Class Codes: H01H 2219/044 Edge lighting of layer
• CPC Class Codes: H01H 2219/062 Light conductor
• CPC Class Codes: H01H 2221/006 Adhesive
• CPC Class Codes: H01H 2221/07 transparent
• CPC Class Codes: H01H 2231/022 Telephone handset

Abstract

For a cell-phone or PDA, the rows of key-caps include respective light-strips, which pick up light from respective LEDs surface-mounted on the PCB. The light-strips are sandwiched between the key-caps and the key-switch actuators (whereby the light-strips move with the keys when the keys are depressed). Sockets for receiving the key-caps are co-molded to the light-strips. Sockets are provided in the resilient webs of the keys for receiving under-blocks co-molded to the light-strips.

Claims

1. An illuminated key-pad unit, having depressible keys, wherein:

[2] the unit includes a set of keys mounted on a base-frame;

[3] the unit includes a light-strip of transparent or translucent light-transmitting material;

[4] the physical structure of the light-strip is such that the light-strip is capable of transmitting light received from a light source along the light-strip, and of radiating that light from an overface of the light-strip;

[5] the keys include respective key-caps;

[6] each key-cap comprises a molding of a transparent or translucent light-transmitting material;

[7] the key-cap has a visible over-surface and a non-visible under-surface;

[8] the overface of the light-strip is in a face-to-face relationship with the under-surface of the key-cap; and

[9] the overface of the light-strip is in a direct light-transmitting relationship with the under-surface of the key-cap.

2. As in claim 1, wherein the overface of the light-strip is in direct touching contact with the under-surface of the key-cap.

3. As in claim 1, wherein the material of the light-strip is flexible, in that the light-strip can be repeatedly flexed and deflected, substantially without damage.

4. As in claim 1, wherein:

[2] the key-caps are provided with respective under-buttons;

[3] the said under-surface of the key-cap is an under-surface of the under-button;

[4] the unit includes respective button-receiving sockets, each shaped to receive the respective under-button;

[5] in respect of each button-receiving socket;

—

[6] the socket is so arranged in the unit that the socket serves to position the under-button laterally and rotationally with respect to the light-strip;

[7] the button-receiving socket is of an opaque material;

[8] the button-receiving socket has side-surfaces that face side-surfaces of the under-button received therein, and those surfaces are opaque to light, and are of a light-reflective nature.

5. As in claim 4, wherein the button-receiving-socket is bonded fast to the overface of the light-strip, for example by being co-molded with the material of the light-strip.

6. As in claim 1, wherein:

[2] the unit includes webs, respective to the key-caps;

[3] the webs are comparatively soft, springy, and resilient, being e.g silicone rubber;

[4] the unit is so configured and arranged that the key-caps are urged by the resilience of the webs into respective rest positions, from which the key-caps can be depressed by manual pressure, against the resilience of the webs.

7. As in claim 6, wherein:

[2] the frame is configured as a grid, in that the frame includes rails that define pockets respective to the key-caps between the rails;

[3] the webs are secured to the rails, and are arranged in the pockets defined by the frame;

[4] located on the webs are respective block-receiving sockets;

[5] the unit includes respective under-blocks, respective to the key-caps, located underneath the light-strip;

[6] the under-blocks have respective upper-surfaces that face an underface of the light-strip, and the upper-surfaces of the under-blocks are opaque to light, and are of a light-reflective nature; and

[7] the block-receiving sockets are so configured and arranged in the unit that the sockets serve to position the respective under-blocks laterally and rotationally with respect to the light-strip.

8. As in claim 7, wherein the under-blocks are bonded fast to the underface of the light-strip, for example by being co-molded with the material of the light-strip.

9. As in claim 1, wherein:

[2] the keys are arranged in the key-pad unit in a plurality of rows of keys;

[3] the key-pad unit includes a corresponding plurality of the light-strips;

[4] the light-strips are disposed respectively side by side along the rows of keys;

[5] the light-strips are linked at their ends by means of respective linking-straps;

[6] the linking-straps are formed with notches, which are hooked under tenons formed in the frame.

10. As in claim 9, wherein:

[2] the frame includes dividing rulers between adjacent rows;

[3] the unit includes light-strips respective to the rows;

[4] the unit includes light-catchers respective to the light-strips.

11. As in claim 1, wherein:

[2] the visible over-surface of the key-cap includes an opaque coating;

[3] a transparent or translucent window in the coating is of such configuration as to signify a key-identification marking;

[4] the physical structure of the key-cap is such that light entering the key-cap through the under-surface of the key-cap can pass through the light-transmitting material of the key-cap, and can emerge through the window.

12. Combination of the unit of claim 1 with a PCB carrying a light-source, wherein:

[2] the light-strip includes a light-catcher, which is so located in the unit as to receive light from the light-source when the unit is assembled to the PCB;

[3] the light-source comprises a light-emitting diode (LED) mounted on, and fixed in, the PCB;

[4] the light-catcher comprises a portion of light-transmitting material that is thicker than the light-strip;

[5] the light-catcher is bonded fast to the material of the light-strip, e.g by being co-molded to the light-strip.

13. Procedure for manufacturing an illuminated key-pad unit, including:

[2] providing a plurality of depressible key-caps, in which each key-cap is of a transparent or translucent light-transmitting material;

[3] providing a corresponding plurality of key-switch-actuators, adapted for contacting respective key-switches mounted on a PCB;

[4] providing a light-strip, of such structure as to be capable of transmitting light received from a light-source, along the light-strip, and of radiating that light from an overface of the light-strip;

[5] bonding the key-caps onto the overface of the light-strip;

[6] bonding the key-switch-actuators onto an underface of the light-strip;

[7] whereby the light-strip resides between the key-caps and their respective key-switch-actuators, and whereby the light-strip is depressed when the key-cap is depressed.

14. As in claim 13, including bonding the key-caps, or the key-switch-actuators, or both, to the light-strips, by gluing.

15. As in claim 13, including assembling the key-pad unit to the PCB, which contains key-switches and which contains a light-source.

16. As in claim 13, including:

[8] providing a light-shield, comprising a strip of opaque sheet material, having a corresponding plurality of cut-outs; and

[9] bonding the key-caps to the light-strip through the respective cut-outs in the light-shield.

17. Procedure for manufacturing an illuminated key-pad unit, including:

[2] providing a plurality of depressible key-caps, in which each key-cap is of a transparent or translucent light-transmitting material;

[3] providing respective profiled under-buttons in the light-transmitting material of the key-caps;

[4] providing respective button-receiving sockets, profiled to receive the under-buttons;

[5] providing a light-strip, of such structure as to be capable of transmitting light received from a light source along the light-strip, and of radiating that light from an overface of the light-strip; and

[6] co-molding the button-receiving sockets to the overface of the light-strip.

18. As in claim 17, including:

[2] providing a corresponding plurality of key-switch-actuators, adapted for contacting respective key-switches mounted on a PCB;

[3] providing the key-switch-actuators with respective block-receiving sockets;

[4] providing respective under-blocks, profiled to fit the block-receiving sockets;

[5] co-molding the block-receiving sockets to an underface of the light-strip.