Electric toothbrushes

• US 20030131427A1
• Filed: 12/05/2002
• Published: 07/17/2003
• Est. Priority Date: 02/08/2001
• Status: Active Grant

• Current Assignee: Braun GmbH (The Procter & Gamble Company)
• Original Assignee: Braun GmbH (The Procter & Gamble Company)
• Inventors: Hilscher, Alexander, Reick, Hansjorg
• Granted Patent: US 7,120,960 B2
• Time in Patent Office: Days
• US Class Current: 15/22.1
• CPC Class Codes: A46B 15/0012 with a pressure controlling device
• CPC Class Codes: A61C 17/3427 Rotation around the axis perpendicular to the axis of toothbrush handle and in the plane defined by the bristle holder
• CPC Class Codes: A61C 17/3436 Rotation around the axis perpendicular to the plane defined by the bristle holder
• CPC Class Codes: A61C 17/3472 with combined movements of the brush body

Abstract

An electric toothbrush has a brush head which is mounted in a movable manner, and a drive for producing an oscillating operating movement in the brush head. The drive includes a cyclically movable drive part and a follower part. The follower part is biased against the drive part so that the follower part follows the drive part'"'"'s cyclic drive movement. A sensor determines the brush head'"'"'s contact pressure by sensing the extent of coupling between the follower part and the drive part, and determining the contact pressure of the brush head based on the extent of coupling.

Claims

1. An electric toothbrush comprising:

a brush head;

a drive that produces an oscillating motion in the brush head, wherein the drive includes a cyclically movable drive part and a follower part connected to the brush head, and wherein the follower part is movably biased toward the drive part; and

a sensor that senses the contact between the drive part and the follower part.

2. The toothbrush of claim 1, wherein the sensor includes a pressure-determining circuit.

3. The toothbrush of claim 2, further comprising an indicator that is connected to the pressure-determining circuit and that displays the contact pressure.

4. The toothbrush of claim 2, wherein the pressure-determining circuit measures the contact pressure based on a duty cycle, and wherein the duty cycle is a function of the portion of the drive part'"'"'s movement cycle when the follower part is coupled to the drive part, and the portion of the movement cycle when they are uncoupled.

5. The toothbrush of claim 2, wherein the pressure-determining circuit includes a filter circuit, the input side of which is connected to the sensor.

6. The toothbrush of claim 2, wherein the pressure-determining circuit includes a computing unit.

7. The toothbrush of claim 6, wherein the computing unit comprises a microcontroller.

8. The toothbrush of claim 7, further comprising an indicator that is connected to the microcontroller and that signals the contact pressure.

9. The toothbrush of claim 8, wherein the indicator comprises an LED display.

10. The toothbrush of claim 1, wherein the follower part is biased against the drive part by a spring.

11. The toothbrush of claim 10, wherein the spring causes the follower part to couple to the drive part for a portion of the duration of the drive part'"'"'s movement cycle when the contact pressure is within a desirable range.

12. The toothbrush of claim 1, wherein the sensor senses electrically conductive contact between the follower part and the drive part.

13. The toothbrush of claim 1, wherein the sensor comprises an on-off switch that is defined by the follower part and the drive part.

14. The toothbrush of claim 1, wherein the drive comprises a stroke drive that produces a translatory stroke movement in the brush head.

15. The toothbrush of claim 1, wherein the drive part comprises a cam that can be rotatably driven.

16. The toothbrush of claim 1, wherein the follower part comprises a portion of a rocker, and wherein one end of the rocker is connected to the brush head, and the other end is biased against the drive part.

17. The toothbrush of claim 1, further comprising an adjusting device that adjusts the force of the follower part against the drive part.