Dual oscillating motor and vibration reduction methods in a personal care appliance

Patent metadata

Field	Value
Publication number	US-2017194849-A1
Application number	US-201514986080-A
Country	US
Kind code	A1
Filing date	Dec 31, 2015
Priority date	Dec 31, 2015
Publication date	Jul 6, 2017
Grant date	—

Abstract

An oscillating motor for a personal care appliance that aims to reduce or substantially eliminate vibration transmitted to the appliance handle. In order to reduce vibration in the handle, the oscillating motor in one embodiment includes dual workpiece mounts. Each workpiece mount is moved independently by one of the two output drives or armatures of the oscillating motor. The oscillating motor utilizes dual, counter-oscillating armatures, each armature/inertial device being configured to offset the inertia generated by the other of the armature/inertial device, thereby creating zero or almost zero moments about the oscillating axis of the workpiece.

First claim

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1 . An electric motor, comprising:
at least one stator configured to be connectable to a source of alternating current; an armature mount defining an axis, the armature mount positioned a spaced distance from the at least one stator; a first armature pivotably coupled to the armature mount about said axis, the first armature including a first magnetic device disposed a spaced distance from the at least one stator and a first device mount configured to be coupleable to a first inertial device, wherein the first armature is configured to exhibit an oscillatory motion about said axis responsive to receipt of alternating current by the at least one stator; a second armature pivotably coupled to the armature mount about said axis, the second armature including a second magnetic device disposed a spaced distance from the at least one stator and a second device mount configured to be coupleable to a second inertial device, wherein the second armature is configured to exhibit oscillatory motion about said axis responsive to receipt of alternating current by the at least one stator, wherein the oscillatory motion of the second armature being opposite the oscillatory motion of the first armature; and at least one linkage interconnecting the first armature and the second armature, wherein the first armature and the second armature have substantially identical mass moments of inertia about said axis.

2 . The electric motor of claim 1 , wherein the device mounts of the first and second armatures are symmetrically disposed with respect to a first plane that bisects the stator.

3 . The electric motor of claim 2 , wherein the first device mount and the second device both lie on a second plane that is orthogonal to the first plane.

4 . The electric motor of claim 1 , wherein the first inertial device is a first workpiece or a first workpiece section.

5 . The electric motor of claim 4 , wherein the second inertial device is selected from the group consisting of a flywheel, a second workpiece, and a second section of a workpiece having first and second sections.

6 . The electric motor of claim 1 , wherein the first and second inertial devices are first and second workpiece sections of a singular workpiece, respectively.

7 . The electric motor of claim 1 , wherein the first and second magnetic devices each include a magnet with a curved configuration that defines an arc, the center of each arc being coincident with said axis.

8 . The electric motor of claim 1 , wherein the first and second magnetic devices each include a pair of magnets, each pair of magnets including a first dipole magnet spaced apart from a second dipole magnet, wherein the first and second dipole magnets are arranged so as to have opposite polarity.

9 . The electric motor of claim 1 , wherein the at least one linkage is a single flat spring.

10 . The electric motor of claim 9 , wherein the flat spring is generally aligned with the first and second device mounts.

11 . The electric motor of claim 1 , wherein the at least one linkage includes two pairs of flexure elements.

12 . The electric motor of claim 1 , wherein the stator includes a monofilar coil having at least 20 gauge wire.

13 . The oscillating electric motor of claim 11 , wherein the at least one stator includes first and second stators, and wherein the first magnetic device is disposed a spaced distance from the first stator and the second magnetic device is disposed a spaced distance from the second stator.

14 . An apparatus, comprising:
a handle; a power source; a drive circuit electrically coupled to the power source and configured to output alternating current; an electric motor carried by the handle and electrically coupled to the drive circuit, wherein the electric motor includes first and second counter-oscillating output drives that oscillate about an axis; first and second workpieces or workpiece sections coupled to the first and second output drives, respectively, for movement therewith, wherein the first output drive and the first workpiece or workpiece section collectively having a mass moments of inertia about said axis substantially the same as a mass moment of inertia of the second output drive and the second workpiece or workpiece section, collectively, about said axis in order to reduce vibration imparted by the oscillating electric motor to the handle.

15 . The apparatus of claim 14 , wherein the first and second workpieces or workpiece sections are cooperatively configured to interleave with one another as each workpiece or workpiece section oscillates.

16 . The apparatus of claim 14 , wherein the first workpiece or workpiece section is cooperatively configured to nest within the second workpiece or workpiece section.

17 . The apparatus of claim 14 , wherein the electric motor includes at least one stator electrically connected to the drive circuit, and wherein the first and second output drives include a first armature configured to move about said axis responsive to receipt of alternating current by the at least one stator and a second armature configured to move about said axis responsive to receipt of alternating current by the at least one stator, and wherein the electric motor further includes at least linkage interconnecting the first armature and the second armature.

18 . The apparatus of claim 17 , wherein the first and second armatures include first and second curved magnets, respectively, and wherein the first and second curved magnets each define an arc, the center of each arc being coincident with said axis.

19 . The apparatus of claim 18 , wherein the first and second curved magnets are mutually aligned and are bisected by a plane that bisects the at least one stator and is coincident with said axis.

20 . A method for reducing vibration imparted by an electric motor to an appliance handle, the electric motor have dual armatures, the method comprising:
driving, with a first armature of the electric motor, a first inertial device in an oscillating manner about an axis, the first inertial device and the first armature collectively having a first mass moment of inertia about said axis; driving, with a second armature of the electric motor, a second inertial device in an oscillating manner about said axis and opposite of the oscillating motion of the first inertial device, wherein the second inertial device and the second armature collectively having a second mass moment of inertia about said axis that is substantially equal to the first mass moment of inertia.

Assignees

• Oreal

Inventors

• Meginniss Iii Stephen M
• Reishus Richard A
• Sabin San Francisco

Classifications

• A61C17/34

  driven by electric motor · CPC title

• A47K7/043

  hand operated · CPC title

• H02K33/12 Primary

  with armatures moving in alternate directions by alternate energisation of two coil systems · CPC title

• H02K7/02

  Additional mass for increasing inertia, e.g. flywheels · CPC title

• A46B5/0008

  Brushes with two or more heads on the same end of a handle not intended for simultaneous use · CPC title