Trackpad with capacitive force sensing

• US 10,534,451 B2
• Filed: 06/01/2018
• Issued: 01/14/2020
• Est. Priority Date: 06/01/2018
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google LLC (Alphabet Inc.)
• Inventors: Costante, Diego Rivas, Vinci, Samuel, Porter, Emily, Jacobs, Steven, Chen, Guangqun, Mittan, Maggie, Ness, Andrew, Mukherjee, Debanjan
• Primary Examiner(s): Edun, Muhammad N
• Application Number:
  US15/996,056
• Publication Number:
  US 20190369759A1
• Time in Patent Office: 592 Days
• CPC Class Codes: G06F 1/1613 for portable computers cooling arrangements therefor G06F1/203; constructional details or arrangements for pocket calculators, electronic agendas or books G06F15/0216; constructional details of portable telephone sets: with several bodies H04M1/0202
• CPC Class Codes: G06F 1/169 the I/O peripheral being an integrated pointing device, e.g. trackball in the palm rest area, mini-joystick integrated between keyboard keys, touch pads or touch stripes G06F1/1643 takes precedence; constructional details of pointing devices G06F3/033
• CPC Class Codes: G06F 2203/0338 Fingerprint track pad, i.e. fingerprint sensor used as pointing device tracking the fingertip image
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/03547 Touch pads, in which fingers can move on a surface
• CPC Class Codes: G06F 3/0414 using force sensing means to determine a position
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: H05K 1/181 associated with surface mounted components
• CPC Class Codes: H05K 7/142 Spacers not being card guides

Abstract

A trackpad includes: a substrate; a circuit board coupled to the substrate for detecting a position of an object adjacent the substrate, the circuit board including a first plate; a second plate including a spring element, wherein a spacer couples the circuit board and the spring element to each other, the spring element facilitating first movement of the substrate and the circuit board relative to the second plate; and a capacitive force sensor that detects a capacitance of the first plate and the second plate. A trackpad can include a spacer coupling the circuit board and the spring element to each other, and facilitating second movement of at least the substrate and the circuit board by a haptic feedback component.

Claims

1. A trackpad comprising:

a substrate providing a trackpad surface;

a circuit board having a first surface coupled to the substrate for detecting a position of an object adjacent the trackpad surface, the circuit board including a first plate at a second surface of the circuit board, the second surface opposite from the first surface;

a second plate including a spring element, wherein a spacer couples the circuit board and the spring element to each other, the spring element facilitating first movement of the substrate and the circuit board relative to the second plate; and

a capacitive force sensor that detects a capacitance of the first plate and the second plate.

2. The trackpad of claim 1, wherein the spring element comprises a finger element in the second plate.

3. The trackpad of claim 1, wherein the second plate is integral with a housing accommodating the trackpad.

4. The trackpad of claim 3, wherein the spring element is formed by a cutout in the housing that defines a finger element.

5. The trackpad of claim 1, wherein the first plate includes a pad on a surface of the circuit board that faces the second plate.

6. The trackpad of claim 1, the capacitive force sensor to detect a change in the capacitance and provide a force signal based on the detected change in capacitance.

7. The trackpad of claim 1, further comprising a dielectric between the first plate and the second plate.

8. The trackpad of claim 7, wherein the dielectric is sized to facilitate the first movement of the substrate and the circuit board relative to the second plate without damage to the circuit board.

9. A trackpad comprising:

a substrate;

a circuit board coupled to the substrate for detecting a position of an object adjacent the substrate, the circuit board including a first plate;

a second plate including a spring element, wherein a spacer couples the circuit board and the spring element to each other, the spring element facilitating first movement of the substrate and the circuit board relative to the second plate; and

a capacitive force sensor that detects a capacitance of the first plate and the second plate;

wherein the spacer includes a stiffener plate for the circuit board and the substrate.

10. The trackpad of claim 9, further comprising a dielectric attached to the stiffener plate.

11. The trackpad of claim 10, wherein the stiffener plate is attached to the circuit board, and wherein the spacer further includes a foam disc between the stiffener plate and the spring element.

12. The trackpad of claim 11, wherein the foam disc comprises a silicone foam disc.

13. A trackpad comprising:

a substrate;

a circuit board coupled to the substrate for detecting a position of an object adjacent the substrate, the circuit board including a first plate;

a second plate including a spring element, wherein a spacer couples the circuit board and the spring element to each other, the spring element facilitating first movement of the substrate and the circuit board relative to the second plate;

a capacitive force sensor that detects a capacitance of the first plate and the second plate; and

a haptic feedback component coupled to at least the substrate.

14. The trackpad of claim 13, wherein the haptic feedback component is coupled to the substrate by being mounted to the circuit board.

15. The trackpad of claim 13, wherein the haptic feedback component comprises a layer abutting the substrate.

16. The trackpad of claim 13, wherein the haptic feedback component is divided between the circuit board and the second plate.

17. The trackpad of claim 16, wherein a coil of the haptic feedback component is mounted to one of the circuit board and the second plate, and wherein a magnet of the haptic feedback component is mounted to another of the circuit board and the second plate, the haptic feedback component providing haptic feedback through the substrate using the coil and the magnet.

18. The trackpad of claim 13, comprising multiple haptic feedback components coupled to the substrate to provide localized haptic feedback.

19. The trackpad of claim 13, wherein the haptic feedback component and the capacitive force sensor are decoupled from each other.

20. The trackpad of claim 19, wherein decoupling is provided by the spring element facilitating the first movement of the substrate and the circuit board relative to the second plate in a first direction, and by a foam disc between the circuit board and the second plate facilitating second movement of the substrate and the circuit board in a second direction essentially perpendicular to the first direction.