Compact low profile magnetic input device

• US 20020093328A1
• Filed: 12/20/2001
• Published: 07/18/2002
• Est. Priority Date: 12/27/2000
• Status: Active Grant

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Eromaki, Marko, Maatta, Esa-Sakari
• Granted Patent: US 6,762,748 B2
• Time in Patent Office: Days
• US Class Current: 324/207.11
• CPC Class Codes: G06F 1/1616 with folding flat displays, e.g. laptop computers or notebooks having a clamshell configuration, with body parts pivoting to an open position around an axis parallel to the plane they define in closed position
• 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 3/03548 Sliders, in which the moving part moves in a plane
• CPC Class Codes: H01H 25/002 having an operating member rectilinearly slidable in different directions
• CPC Class Codes: H01H 36/0026 comprising a biasing, helping or polarising magnet
• CPC Class Codes: H01H 36/0066 magnet being removable, e.g. part of key pencil

Abstract

The invention discloses a low profile input device for moving a cursor, scrolling a page, or selecting a function on a display of a handheld device. In an embodiment of the invention, a planar joystick (402,940) for use moving a cursor on the display of a handheld device comprises a movable sliding button having a first magnet M1 embedded therein. The button is slid by a user'"'"'s finger over a second magnet M2, an action that distorts the magnetic flux 418 which is detected by a plurality of magnetic flux sensors 420. The direction and magnitude of the cursor movement on the display correspond to the change in flux caused by the movement of the sliding button.

Claims

1. An input device for moving a cursor on a display screen comprising:

a device housing;

a movable sliding member having a first ferromagnetic element attached thereto;

a second ferromagnetic element located in a fixed position relative to the first ferromagnetic element; and

at least two sensors for measuring the relative movement of the sliding member.

2. An input device according to claim 1 wherein the first ferromagnetic element and second ferromagnetic element combine to provide a centering effect for the sliding member.

3. An input device according to claim 1 wherein the first ferromagnetic element and the second ferromagnetic element are shaped as annular rings.

4. An input device according to claim 1 wherein the sensors are magnetic flux sensors that generate a current proportional to the density of the detected flux which is translated to signals interpreted by the input device into cursor movement.

5. An input device according to claim 1 wherein the motion of the sliding member is restricted to movement in one dimension by traveling within a groove or on a rail.

6. An input device according to claim 1 wherein the slide element is slidably engaged within a recess in the device housing.

7. An electronic device comprising a display screen for displaying a cursor during operation of the device, the electronic device is characterized in that the device includes an input device for moving a cursor on a display comprising:

a movable sliding member having a first ferromagnetic element attached thereto;

a second ferromagnetic element located in a fixed position relative to the first ferromagnetic element; and

at least two sensors for measuring the relative movement of the sliding member.

8. A electronic device according to claim 7 wherein the first ferromagnetic element and second ferromagnetic element combine to provide a centering effect for the sliding member.

9. A electronic device according to claim 7 wherein the first magnet and second magnet are permanent annular ring magnets.

10. A electronic device according to claim 7 wherein the sensors are magnetic flux sensors that generate a current proportional to the density of the detected flux which is translated to signals interpreted by the electronic device into cursor movement.

11. A electronic device according to claim 7 wherein the motion of the sliding member is restricted to movement in one dimension by traveling within a groove or on a rail.

12. A electronic device according to claim 7 wherein the slide element is slidably engaged within a recess in the device housing.

14. A discrete sliding input device according to claim 13 wherein the sliding member moves in one dimensional motion between the first position and the second position within a groove or on a rail.

15. A discrete sliding input device according to claim 13 wherein the sliding member moves in a two dimensional manner in discrete steps.

13. A sliding input device moving in discrete steps between a first fixed position and a second fixed position for selecting a function on a electronic device, the input device comprising:

a movable sliding member having a first magnet attached thereto;

a second magnet fixed in position at the first fixed position;

a third magnet fixed in position at the second fixed position a proximate distance from the first position;

a support layer for supporting the second magnet and the third magnet in their respective fixed positions; and

at least two sensors for detecting the position of the sliding member.

16. A method of moving a cursor on a display screen with an input device by sliding a slide element attached to a first magnet over a second magnet located in a fixed position, whereby by relative movement of the slide element is measured by at least two sensors and translated into movement of the cursor.