Linear electro-polymer motors and devices having the same

• US 9,099,939 B2
• Filed: 07/25/2012
• Issued: 08/04/2015
• Est. Priority Date: 07/25/2011
• Status: Active Grant

• Current Assignee: Braun GmbH (The Procter & Gamble Company)
• Original Assignee: Braun GmbH (The Procter & Gamble Company)
• Inventors: Jungnickel, Uwe, Heil, Benedikt
• Primary Examiner(s): Rosenau, Derek
• Application Number:
  US13/557,245
• Publication Number:
  US 20130025079A1
• Time in Patent Office: 1,105 Days
• Field of Search: 310/328, 310/800
• US Class Current: 1/1
• CPC Class Codes: A61C 17/3436 Rotation around the axis perpendicular to the plane defined by the bristle holder
• CPC Class Codes: A61C 17/3445 Translation along the axis of the toothbrush handle
• CPC Class Codes: B26B 19/282 Motors without a rotating central drive shaft, e.g. linear motors
• CPC Class Codes: H02N 2/02 producing linear motion, e.g. actuators; Linear positioners ; Linear motors
• CPC Class Codes: H02N 2/046 for conversion into rotary motion

Abstract

A linear electro-polymer motor includes a fixed member, a linear shaft having an axis, a polymer actuator, and a bias member. The polymer actuator includes a first end fixedly connected to the linear shaft and a second end fixedly connected to the fixed member. The bias member includes a first end fixedly connected to the linear shaft and a second end fixedly connected to the fixed member. The polymer actuator changes length after receipt of voltage to linearly move the linear shaft along the axis.

Claims

1. A linear electro-polymer motor comprising:

a fixed member;

a linear shaft having an axis associated therewith;

a polymer actuator comprising a first end and a second end, wherein the first end of the polymer actuator is fixedly connected to the linear shaft and the second end of the polymer actuator is fixedly connected to the fixed member; and

a bias member comprising a first end and a second end, wherein;

the first end of the bias member is fixedly connected to the linear shaft;

the second end of the bias member is fixedly connected to the fixed member such that a spring force provided by the bias member opposes a movement of the linear shaft provided by the polymer actuator; and

the polymer actuator changes length after receipt of voltage to move the linear shaft along the axis,

wherein the bias member comprises a second polymer actuator.

2. The linear electro-polymer motor of claim 1, wherein the bias member comprises a spring.

3. The linear electro-polymer motor of claim 1, further comprising a guiding sleeve, wherein the linear shaft is positioned through the guiding sleeve such that the movement of the linear shaft is substantially linear.

4. A device comprising:

a device housing defining a device enclosure therein; and

a linear electro-polymer motor at least partially positioned within the device enclosure defined by the device housing, the linear electro-polymer motor comprising;

a linear shaft having an axis associated therewith;

a polymer actuator comprising a first end and a second end, wherein the first end of the polymer actuator is fixedly connected to the linear shaft and the second end of the polymer actuator is fixedly connected to the device housing within the device enclosure; and

a bias member comprising a first end and a second end, wherein;

the first end of the bias member is fixedly connected to the linear shaft;

the second end of the bias member is fixedly connected to the device housing such that a spring force provided by the bias member opposes a movement of the linear shaft provided by the polymer actuator; and

the polymer actuator changes length after receipt of voltage to move the linear shaft along the axis,

wherein the linear shaft comprises an actuator protrusion and the polymer actuator is fixedly connected to the actuator protrusion and the bias member comprises a first flat spring and a second flat spring.

5. The device of claim 4, wherein the linear shaft at least partially extends out of the device enclosure defined by the device housing.

6. The device of claim 4, wherein the device is an electric toothbrush.

7. The device of claim 4, further comprising an adapter removably coupled to the linear shaft, wherein linear movement of the linear shaft moves the adapter along the axis of the linear shaft.

8. The device of claim 4, wherein:

the first and second flat springs each comprise a first end, and two outer arms and a middle arm extending from the first end;

a lower portion of the two outer arms are fixedly connected to the support wall of the chassis;

the middle arm is not fixedly connected to the device housing such that the middle arm acts as a cantilever spring portion; and

the linear shaft is fixedly connected to the middle arm of the first and second flat springs.

9. The device of claim 4, further comprising:

a chassis comprising a support wall, a first side wall, and a second side wall, wherein the chassis is fixedly connected to the device housing within the device enclosure;

a first actuator coupling plate and a second actuator coupling plate, wherein the linear shaft is fixedly positioned through the first actuator coupling plate and the second actuator coupling plate; and

a second polymer actuator comprising a first end and a second end, wherein the first end is fixedly connected to the second actuator coupling plate and the second end is fixedly connected to the second side wall of the chassis, wherein;

the first end of the polymer actuator is fixedly connected to the first actuator coupling plate and the second end of the polymer actuator is fixedly connected to the first side wall of the chassis;

the bias member comprises a first flat spring and a second flat spring; and

the first and second flat springs flexibly couple the linear shaft to the chassis.

10. The device of claim 9, wherein:

the first and second flat springs each comprise a first end, and two outer arms and a middle arm extending from the first end;

a lower portion of the two outer arms are fixedly connected to the support wall of the chassis;

the middle arm is not fixedly connected to the device housing such that the middle arm acts as a cantilever spring portion; and

the linear shaft is fixedly connected to the middle arm of the first and second flat springs.

11. The device of claim 9, wherein the first actuator coupling plate, the second actuator coupling plate, the first flat spring, and the second flat spring are orientated normal to the axis of the linear shaft.

12. A device comprising:

a device housing defining a device enclosure therein; and

a linear electro-polymer motor at least partially positioned within the device enclosure defined by the device housing, the linear electro-polymer motor comprising;

an actuator base coupled to the device housing within the device enclosure by an actuator spring;

a linear shaft having an axis associated therewith;

a polymer actuator comprising a first end and a second end, wherein the first end of the polymer actuator is fixedly connected to the linear shaft and the second end of the polymer actuator is fixedly connected to the actuator base;

a return spring having a first end fixedly connected to the actuator base and a second end fixedly connected to the linear shaft; and

a bias member comprising a first end and a second end, wherein;

the first end of the bias member is fixedly connected to the linear shaft;

the second end of the bias member is fixedly connected to the device housing; and

the polymer actuator changes length after receipt of a voltage,

wherein the device further includes an adapter comprising a first end, a second end, a recess extending between the first end and the second end, a push rod coupled to the linear shaft at a first end of the push rod, and a rotating member, wherein the rotating member is coupled to the push rod at a second end of the push rod, linear movement of the linear shaft oscillates the rotating member about a rotational axis, and the second end of the adapter is removably coupled to the actuator base such that application of voltage to the polymer actuator linearly moves the adapter and the linear shaft with respect to the device housing.

13. The device of claim 12, wherein the device is an electric toothbrush.

14. A device comprising:

a base located in a first plane;

an oscillation bridge flexibly coupled to the base and located in a second plane parallel to the first plane; and

a polymer actuator comprising a first end and a second end, wherein the first end of the polymer actuator is coupled to the base and a second end of the polymer actuator is coupled to the oscillation bridge, and a voltage applied to the polymer actuator translates the oscillation bridge with respect to the base such that the oscillation bridge linearly travels within the second plane,

wherein the base comprises an upper surface, a first polymer actuator mount extending from the upper surface, and a second polymer actuator mount extending from the upper surface, wherein the first polymer actuator mount is in a first vertical plane and the second polymer actuator mount is in a second vertical plane, the oscillation bridge comprises an upper surface, a first end, a second end, a lower surface, a first leaf spring extending from the first end of the oscillation bridge and fixedly connected to the upper surface of the base, a second leaf spring extending from the second end of the oscillation bridge and fixedly connected to the upper surface of the base, a third polymer actuator mount extending from the lower surface and located in the first vertical plane, the third polymer actuator mount is opposite from the second polymer actuator mount, and a fourth polymer actuator mount extending from the lower surface and located in the second vertical plane, wherein the fourth polymer actuator mount is opposite from the first polymer actuator mount;

wherein the polymer actuator further comprises a first polymer actuator comprising a first end and a second end, wherein the first end is fixedly connected to the first polymer actuator mount and the second end is fixedly connected to the fourth polymer actuator mount; and

a second polymer actuator comprising a first end and a second end, wherein the first end is fixedly connected to the second polymer actuator mount and the second end is fixedly connected to the third polymer actuator mount; and

an alternating voltage applied to the first polymer actuator and the second polymer actuator causes the oscillation bridge to linearly translate in the second plane.

15. The device of claim 14, further comprising a blade assembly comprising a plurality of blades, the blade assembly fixedly coupled to the upper surface of the oscillation bridge.