Keypad in textiles with capacitive read-out circuit

• US 20050069695A1
• Filed: 06/14/2004
• Published: 03/31/2005
• Est. Priority Date: 12/14/2001
• Status: Active Grant

• Current Assignee: Future-Shape GmbH
• Original Assignee: Infineon Technologies AG
• Inventors: Jung, Stefan, Lauterbach, Christl
• Granted Patent: US 7,230,610 B2
• Time in Patent Office: Days
• US Class Current: 428/328
• CPC Class Codes: D03D 1/0088 Fabrics having an electronic function
• CPC Class Codes: D03D 15/67 Metal wires
• CPC Class Codes: D10B 2101/20 Metallic fibres
• CPC Class Codes: D10B 2401/16 antistatic; conductive
• CPC Class Codes: H01H 2203/0085 Layered switches integrated into garment, clothes or textile
• CPC Class Codes: H01H 2239/006 Containing a capacitive switch or usable as such
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2017/9602 characterised by the type or shape of the sensing electrodes
• CPC Class Codes: H03K 2217/960755 Constructional details of capacitive touch and proximity switches
• CPC Class Codes: Y10T 428/256 Heavy metal or aluminum or compound thereof

Abstract

Input apparatus including at least one textile fabric carrier, at least one flexible, wire- and/or thread-like electrical conductor comprising at least one weft and/or warp thread of the fabric carrier, and at least one electrically conductive, flexible key device which is electrically connected to a key connection of the conductor, wherein the conductor is designed for the connection of an evaluation device.

Claims

1. An input apparatus comprising:

at least one textile fabric carrier;

at least one flexible, wire-like and/or thread-like electrical conductor comprising at least one weft and/or warp thread of the fabric carrier; and

at least one electrically conductive, flexible key device which is electrically connected to a key connection of the conductor;

wherein the conductor is designed for the connection of an evaluation device.

2. The input apparatus as claimed in claim 1, wherein the key device comprises a conductive silicone adhesive.

3. The input apparatus as claimed in claim 1, wherein the key device has a key layer whose thickness is small relative to its dimensions in the layer plane and which is areally fixed to the fabric carrier.

4. The input apparatus as claimed in claim 1, wherein the conductor has an electrical insulation, which is locally removed for electrical connection to the key device.

5. The input apparatus as claimed in claim 1, further comprising a plurality of key devices arranged in particular linearly or in matrix-like fashion.

6. The input apparatus as claimed in claim 5, wherein the conductors are electrically connected to the key devices in each case being electrically connected at crossover points to contact redistribution conductors which run essentially perpendicularly thereto and in each case comprise at least one electrically conductive weft or warp thread of the fabric carrier.

7. The input apparatus as claimed in claim 6, wherein the contact redistribution conductor are arranged in a manner spaced apart uniformly from one another in the fabric carrier.

8. The input apparatus as claimed in claim 1, further comprising an evaluation device for detecting an actuation of at least one of the key devices.

9. The input apparatus as claimed in claim 8, wherein a first group of key devices is designed as reference key devices and a second group of key devices is designed as input key devices.

10. The input apparatus as claimed in claim 9, wherein the evaluation device is designed for evaluating electrical potential difference or electrical resistance between one of the input key devices and at least one of the reference key devices.

11. The input apparatus as claimed in claim 9, wherein the input key devices are connected, by a conductor arranged in the fabric carrier, serially and with high impedance to an input connection of the evaluation device and the reference key devices are connected with low impedance to a reference connection of the evaluation device.

12. The input apparatus as claimed in claim 11, wherein the evaluation device is designed for detecting an actuation of one of the input key devices by evaluation of the electrical resistance between the input and reference connections.

13. The input apparatus as claimed in claim 8, wherein the evaluation device is designed for outputting a control signal if it detects an actuation of at least two of the key devices in a predetermined temporal sequence.

14. The input apparatus as claimed in claim 8, wherein the evaluation device is designed for capacitively detecting an actuation of at least one of the key devices.

15. The input apparatus as claimed in claim 14, further comprising an electrical shielding device, which is designed for electrically shielding at least one of the key devices from a side of the textile fabric carrier.

16. The input apparatus as claimed in claim 15, wherein the shielding device is a thin conductive layer arranged spaced apart from and running essentially parallel to the at least one of the key devices.

17. A method for producing an input apparatus comprising the steps of:

providing a textile fabric carrier having at least one flexible, wire-like and/or thread-like electrical conductor comprising at least one weft and/or warp thread of the fabric carrier;

electrically connecting an electrically conductive, flexible key device to a key connection of the conductor; and

connecting an evaluation device to the conductor.

18. The method as claimed in claim 17, wherein the key device is fitted using a screen printing method.

19. The method as claimed in claim 17, wherein an electrical insulation of the conductor is locally removed before the step of electrically connecting the key device.