Keyboard assemblies having reduced thicknesses and method of forming keyboard assemblies

• US 10,128,064 B2
• Filed: 09/12/2016
• Issued: 11/13/2018
• Est. Priority Date: 05/13/2015
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Leong, Craig C., Zercoe, Bradford J., La, Thai Q., Cao, Robert Y., Lehmann, Alex J., Mathew, Dinesh C.
• Primary Examiner(s): Jimenez, Anthony R.
• Application Number:
  US15/262,249
• Publication Number:
  US 20160379775A1
• Time in Patent Office: 792 Days
• Field of Search: 200 5 A, 200402, 200405, 200406, 200408, 200412, 200440, 200468
• CPC Class Codes: G06F 1/1662 Details related to the integrated keyboard
• CPC Class Codes: H01H 13/10 Bases; Stationary contacts mounted thereon
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 13/7065 characterised by the mechanism between keys and layered keyboards
• CPC Class Codes: H01H 13/807 characterised by the spatial arrangement of the contact sites, e.g. superimposed sites
• 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 2203/028 embedded in layer material
• CPC Class Codes: H01H 2205/026 Adhesive sheet
• CPC Class Codes: H01H 2215/006 Only mechanical function
• CPC Class Codes: H01H 2231/002 Calculator, computer
• CPC Class Codes: H01H 3/125 using a scissor mechanism as stabiliser

Abstract

Keyboard assemblies having reduced thicknesses and methods of forming the same. A keyboard assembly may include a printed circuit board (PCB) and a single membrane sheet adhered directly to the PCB. The single membrane sheet may substantially cover the PCB. The keyboard assembly may also include a group of dome switches coupled directly to the single membrane sheet. Another keyboard assembly may include a group of conductive pads and a group of membrane pads. Each of the group of membrane pads may be adhered directly to a corresponding one of the group of conductive pads. The keyboard assembly may also include a group of dome switches coupled directly to the membrane pads. Each of the group of dome switches may be coupled directly to a corresponding one of the group of membrane pads.

Claims

1. A keyboard assembly, comprising:

a key cap configured to receive a user input;

a collapsible dome positioned below the key cap and having a peripheral portion and a top portion;

a membrane pad positioned below the collapsible dome and coupled to the peripheral portion, the membrane pad comprising a center conductor separated from the top portion when the dome is in an uncollapsed state;

a switch housing having an opening in which the collapsible dome is positioned;

a hinge mechanism surrounding the switch housing and supporting the key cap above the collapsible dome; and

a printed circuit board (PCB) connected to the switch housing and the membrane pad, wherein;

the user input received at the key cap causes the top portion of the dome to displace the center conductor such that the center conductor contacts the PCB.

2. The keyboard assembly of claim 1, wherein the membrane pad is a substantially flexible material that deforms upon input from the top portion of the collapsible dome.

3. The keyboard assembly of claim 1, wherein the membrane pad further comprises:

a ring conductor positioned on the peripheral portion of the collapsible dome and electrically coupled with the center conductor and an outer contact of the PCB when the dome is in an uncollapsed state.

4. The keyboard assembly of claim 3, wherein:

the center conductor contacts an inner contact of the PCB in response to the input of the dome; and

the ring and center conductors form an electrically conductive path between the outer and inner contacts of the PCB when the dome is in a collapsed state.

5. The keyboard assembly of claim 3, wherein the membrane pad further comprises:

an intermediate conductive spacer positioned between the ring conductor and the center conductor.

6. The keyboard assembly of claim 5, wherein the intermediate conductive spacer is defined by a material that is distinct from the ring conductor and the center conductor.

7. The keyboard assembly of claim 6, wherein the intermediate conductive spacer is electrically conductive adhesive.

8. A keyboard assembly, comprising:

a printed circuit board (PCB);

an array of membrane pads coupled to the PCB, each membrane pad of the array of membrane pads having a center portion separated from the PCB;

an array of deformable structures, each deformable structure of the array of deformable structures coupled to a corresponding one of the array of membrane pads opposite the PCB; and

an array of key caps positioned over the array of deformable structures, wherein;

each of the array of key caps is configured to displace a corresponding deformable structure such that the center portion of an associated membrane pad contacts the PCB.

9. The keyboard assembly of claim 8, wherein the array of deformable structures is one of adhered or laminated to the corresponding one of the array of membrane pads.

10. The keyboard assembly, of claim 8, wherein the PCB includes a pair of electrical contacts for each of the array of membrane pads.

11. The keyboard assembly of claim 10, wherein each of the array of membrane pads includes:

an inner electrode defining the center portion;

an intermediate conductive spacer surrounding the inner electrodes; and

an outer electrode surrounding the intermediate conductive spacer.

12. The keyboard assembly of claim 11, wherein for each of the array of membrane pads:

the outer electrode contacts a first of the pair of electrical contacts when a corresponding deformable structure of the array of deformable structures is in an undeformed state; and

the inner electrode contacts a second of the pair of electrical contacts when the corresponding deformable structure is in a deformed state.

13. The keyboard assembly of claim 12, wherein for each of the array of membrane pads:

the corresponding pair of electrical contacts are electrically isolated on a surface of the PCB; and

the outer electrical contact, intermediate conductive spacer, and inner electrical contact form an electrically conductive path between the pair of electrical contacts when the corresponding deformable structure is in the deformed state.

14. The keyboard assembly of claim 8, wherein each of the array of deformable structures is a dome-shaped member.

15. The keyboard assembly of claim 14, wherein the dome-shaped member is configured to provide a predetermined tactile response when an associated membrane pad contacts the PCB in response to a user input.

16. A keyboard assembly, comprising:

a printed circuit board (PCB) comprising inner and outer conductive contact pads and defining an aperture extending through the inner conductive contact pad;

a membrane layer having a pair of concentric electrodes, a first of the pair of concentric electrodes directly adhered to the outer conductive contact pad and a second of the pair of electrodes positioned above the PCB and in substantial alignment with the aperture;

a dome positioned above the membrane layer; and

a keycap configured to collapse the dome in response to a user input, wherein the dome, in a collapsed state;

partially extends into the aperture; and

causes the second of the pair of electrodes to contact the inner conductive contact pad.

17. The keyboard assembly of claim 16, wherein the aperture is configured to provide a predetermined tactile response to a user.

18. The keyboard assembly of claim 16, wherein:

the first of the pair of concentric electrodes has a diameter that is larger than a diameter of the outer conductive contact pad; and

the second of the pair of concentric electrodes has a diameter that is smaller than a diameter of the inner conductive contact pad.

19. The keyboard assembly of claim 16, wherein:

the pair of concentric electrodes are electrically coupled on the membrane layer; and

the inner and outer conductive contact pads are electrically isolated from one another on the PCB.

20. The keyboard assembly of claim 19, wherein:

the contacting of the second of the pair of concentric electrodes completes an electrically conductive path between the inner and outer conductive contact pads using the membrane layer.