TOUCHSURFACE ASSEMBLY HAVING KEY GUIDES FORMED IN A SHEET METAL COMPONENT

• US 20140262716A1
• Filed: 06/26/2013
• Published: 09/18/2014
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Weber, Christopher Todd, Telin, Brad Lee
• Granted Patent: US 9,384,919 B2
• Time in Patent Office: Days
• US Class Current: 200/5.A
• CPC Class Codes: H01H 13/76 wherein some or all of the operating members actuate different combinations of the contact sets, e.g. ten operating members actuating different combinations of four contact sets
• CPC Class Codes: H01H 13/85 characterised by tactile feedback features
• CPC Class Codes: H01H 13/88 Processes specially adapted for manufacture of rectilinearly movable switches having a plurality of operating members associated with different sets of contacts, e.g. keyboards
• CPC Class Codes: H01H 2221/026 Guiding or lubricating nylon
• CPC Class Codes: H01H 2221/04 magnetic
• CPC Class Codes: H01H 2239/006 Containing a capacitive switch or usable as such
• CPC Class Codes: H03K 17/975 using a capacitive movable element

Abstract

Methods and apparatus for a touchsurface assembly such as a key assembly are described. The touchsurface assembly includes a sheet metal component having ramps formed therein and a keycap having ramp contacting features and a touchsurface for receiving a press force that moves the keycap toward a pressed position. The ramp contacting features contact at least one of the ramps in the sheet metal component while the keycap moves toward the pressed position, the ramps guiding the keycap to move in a second direction orthogonal to the press direction as the keycap moves from the unpressed position toward the pressed position.

Claims

1. A key assembly, comprising:

a sheet metal component having ramps formed therein; and

a keycap having ramp contacting features and a touchsurface for receiving a press force that moves the keycap toward a pressed position;

wherein the ramp contacting features contact at least one of the ramps while the keycap moves toward the pressed position, the ramps guiding the keycap to move in a second direction orthogonal to the press direction as the keycap moves from the unpressed position toward the pressed position.

2. The key assembly of claim 1, wherein the sheet metal component comprises a chassis for the key assembly.

3. The key assembly of claim 1, wherein the ramps are formed in the sheet metal component by a stamping process.

4. The key assembly of claim 1, further comprising a biasing mechanism that biases the keycap toward the unpressed position, wherein the biasing mechanism comprises:

a magnet fixed to the keycap; and

a magnet attracting feature formed in the sheet metal component.

5. The key assembly of claim 1, further comprising a biasing mechanism that biases the keycap toward the unpressed position, wherein the biasing mechanism comprises:

a first magnet fixed to the keycap; and

a second magnet disposed on a magnet supporting feature formed in the sheet metal component.

6. The key assembly of claim 1, wherein the ramps are formed in the sheet metal component by:

punching to create tabs in the sheet metal component; and

bending the tabs to form the ramps.

7. The key assembly of claim 1, wherein the ramps have a slope between 55-60 degrees relative to a plane of the sheet metal component.

8. The key assembly of claim 1, wherein the ramps comprise compound folds, and the ramps are formed in the sheet metal component by:

punching to create tabs in the sheet metal component;

bending the tabs at an intermediate location to form side retention features of the ramps; and

bending the tabs at a base location to form the ramps.

9. The key assembly of claim 1, further comprising a friction reducing coating applied to the ramps.

10. The key assembly of claim 1, further comprising a capacitive sensor for sensing when the keycap is in the pressed position.

11. The key assembly of claim 1, wherein the sheet metal component has second ramps formed therein, the key assembly further comprising:

a second keycap having ramp contacting features and a touchsurface for receiving a press force that moves the keycap toward the pressed position;

wherein the ramp contacting features of the second keycap contact the second ramps while the second keycap moves toward the pressed position, the second ramps guiding the second keycap to move in a second direction orthogonal to the press direction as the second keycap moves from the unpressed position toward the pressed position.

12. A keyboard, comprising:

a sheet metal component having a plurality of ramps formed therein; and

a plurality of keycaps each having ramp contacting features and a touchsurface for receiving a press force;

wherein the ramp contacting features of a pressed keycap contacts at least one of the plurality of ramps associated with the pressed keycap while the pressed keycap moves toward the pressed position, the at least one of the plurality of ramps guiding the pressed keycap to move in a second direction orthogonal to the press direction as the pressed keycap moves from the unpressed position toward the pressed position.

13. The keyboard of claim 12, wherein the sheet metal component comprises a chassis for the keyboard and wherein the plurality of ramps are formed in the sheet metal component by a stamping process.

14. The keyboard of claim 12, further comprising a plurality of biasing mechanisms that biases a respective keycap of the plurality of keycaps toward the unpressed position, wherein each of the plurality of biasing mechanisms comprises:

a magnet fixed to the respective keycap; and

a magnet attracting feature formed in the sheet metal component.

15. The keyboard of claim 12, wherein the plurality of ramps are formed in the sheet metal component by:

punching to create a plurality of tabs in the sheet metal component; and

bending the plurality of tabs to form the plurality of ramps.

16. The keyboard of claim 12, further comprising a friction reducing coating applied to each of the plurality of ramps.

17. A method of manufacturing a key assembly having the keycap configured to move between an unpressed position and a pressed position relative to a base, wherein the unpressed and pressed positions are separated in a press direction and in a lateral direction orthogonal to the press direction, the method comprising:

stamping ramps in a piece of sheet metal, the ramps providing guiding surfaces for ramp contacting features in the keycap that guide the keycap in the lateral direction while the keycap moves toward the pressed position.

18. The method of claim 17, wherein the stamping of the ramps includes:

stamping the piece of sheet metal to form tabs; and

bending the tabs to form the ramps.

19. The method of claim 18, wherein the stamping of the ramps further includes forming keycap leveling features by bending edges of the ramps toward the lateral direction.

20. The method of claim 17, further comprising creating a portion of a biasing mechanism in the piece of sheet metal.