Integrated optical encoder

• US 20060202114A1
• Filed: 03/13/2006
• Published: 09/14/2006
• Est. Priority Date: 09/11/2003
• Status: Active Grant

• Current Assignee: PREH GmbH (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: PREH GmbH (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Ruttiger, Anton, Ofenhitzer, Thomas, Peschel, Markus
• Granted Patent: US 7,345,273 B2
• Time in Patent Office: Days
• US Class Current: 250/231.130
• CPC Class Codes: G01D 5/3473 Circular or rotary encoders
• CPC Class Codes: H03M 1/301 Constructional details of parts relevant to the encoding mechanism, e.g. pattern carriers, pattern sensors

Abstract

A rotary switch including a control element, a light-emitting device arranged on a printed circuit board and configured to emit light, and at least two receivers arranged on the printed circuit board in correspondence with the light-emitting device and configured to detect switching positions of the rotary switch. Further, the light-emitting device is mounted radially at an outside portion of inside of a hollow cylindrical extension of the control element, and wherein on level with the light-emitting device, the extension includes orifices evenly distributed around a periphery of the extension, and that opposite the light-emitting device, on an exterior side of the extension, the at least two receivers are arranged.

Claims

1. A rotary switch, comprising:

a control element;

a light-emitting device arranged on a printed circuit board and configured to emit light; and

at least two receivers arranged on the printed circuit board in correspondence with the light-emitting device and configured to detect switching positions of the rotary switch,

wherein the light-emitting device is mounted radially at an outside portion of inside of a hollow cylindrical extension of the control element, and

wherein on level with the light-emitting device, the extension includes orifices evenly distributed around a periphery of the extension, and that opposite the light-emitting device, on an exterior side of the extension, the at least two receivers are arranged.

2. The rotary switch of claim 1, further comprising:

a stationary shadow mask arranged between the extension and the receivers and configured to focus light emitted by the light-emitting device in the direction of the at least two receivers.

3. The rotary switch of claim 1, wherein the at least two receivers are arranged side-by-side in a plane that is at right angles with the printed circuit board.

4. The rotary switch of claim 1, wherein the orifices in the extension are spaced to provide the following settings:

each receiver is individually masked;

both receivers are simultaneously masked; and

neither receiver is masked.

5. The rotary switch of claim 1, wherein the control element is part of a control unit in a motor vehicle, the light-emitting device is a light-emitting diode (LED), each receiver is a phototransistor, and the LED and the phototransistors are connected to one another via an electric circuit arrangement.

6. A rotary switch, comprising:

a light-emitting unit configured to emit light;

a rotatable hollow cylindrical extension surrounding the light-emitting unit;

at least two receivers arranged outside of the rotatable extension in correspondence with the light-emitting unit and configured to detect light transmitted from the light-emitting unit; and

a control element configured to rotate the rotatable extension,

wherein the rotatable extension includes orifices around a periphery of the extension such that as the control element rotates the extension to a particular position, the light emitted by the light-emitting unit either passes through the orifices of the extension or is blocked by the extension.

7. The rotary switch of claim 6, further comprising:

an electronic circuit configured to generate bit patterns based on whether or not the light emitted by the light-emitting unit passes through the orifices and is received by any of the at least two receivers.

8. The rotary switch of claim 7, wherein in a first position, the extension is positioned such that the orifices allow the light emitted by the light-emitting unit to pass through and be received by only a first one of the at least two receivers.

9. The rotary switch of claim 8, wherein in a second position, the extension is positioned such that the orifices allow the light emitted by the light-emitting unit to pass through and be received by both of the at least two receivers.

10. The rotary switch of claim 9, wherein in a third position, the extension is positioned such that the orifices allow the light emitted by the light-emitting unit to pass through and be received by only a second one of the at least two receivers.

11. The rotary switch of claim 10, wherein in a fourth position, the extension is positioned such that the orifices are not arranged to allow the light emitted by the light-emitting unit to pass through and be received by any of the at least two receivers.

12. The rotary switch of claim 11, wherein the electronic circuit determines whether the extension has been rotated in a clockwise or counter-clockwise direction based on the first, second, third and fourth positions.

13. The rotary switch of claim 6, wherein the light-emitting unit and the at least two receivers are decoupled from the control element.

14. The rotary switch of claim 6, wherein the light-emitting unit and the at least two receivers are mounted on a printed circuit board.

15. The rotary switch of claim 14, wherein the at least two receivers are arranged side-by-side in a plane that is at right angles with the printed circuit board.

16. The rotary switch of claim 6, further comprising:

a stationary shadow mask arranged between the rotatable extension and the at least two receivers and configured to focus light emitted by the light-emitting unit in the direction of the at least two receivers.

17. The rotary switch of claim 6, wherein the orifices in the extension are spaced to provide the following settings:

each receiver is individually masked;

both receivers are simultaneously masked; and

neither receiver is masked.

18. The rotary switch of claim 6, further comprising:

a light-emitting diode arranged in a center of the of the rotatable extension and configured to illuminate the control element.

19. The rotary switch of claim 6, wherein the control element is associated with a control knob of the rotary switch.

20. The rotary switch of claim 6, wherein the control element is part of a control unit in a motor vehicle, the light-emitting device is a light-emitting diode (LED), each receiver is a phototransistor, and the LED and the phototransistors are connected to one another via an electric circuit arrangement.