ELECTRIC HAIR CUTTER

• US 20180207817A1
• Filed: 01/22/2018
• Published: 07/26/2018
• Est. Priority Date: 01/26/2017
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: WANG, Wei, Yamaguchi, Takashi, Yan, Qinghui
• Granted Patent: US 10,737,402 B2
• Time in Patent Office: Days
• CPC Class Codes: B26B 19/06 involving co-operating cutting elements both of which have shearing teeth
• CPC Class Codes: B26B 19/105 with a secondary cutting unit being rotated into an operating position
• CPC Class Codes: B26B 19/28 Drive layout for hair clippers or dry shavers, e.g. providing for electromotive drive electric motors per se H02
• CPC Class Codes: B26B 19/3846 Blades; Cutters B26B19/044, B26B19/141 take precedence
• CPC Class Codes: B26B 19/3853 Housing or handle
• CPC Class Codes: F16H 25/20 Screw mechanisms with automatic reversal F16H25/12

Abstract

An electric hair cutter includes a motion conversion mechanism that converts rotary motion of an output shaft of an electric motor into reciprocating linear motion and a movable blade driven by reciprocating linear motion of the motion conversion mechanism. The motion conversion mechanism includes a first conversion portion, converting rotary motion of the output shaft into reciprocating rotary motion about a first axis, a second conversion portion, converting the reciprocating rotary motion into reciprocating linear motion, and an output portion, coupling the second conversion portion to the movable blade. The second conversion portion includes a motion transmission part, coupling the first conversion portion to the output portion, and an elastic deformation part coupled to the motion transmission part to restrict motion of the motion transmission part caused by motion components differing from a motion component in an output direction so that the motion transmission part linearly reciprocates.

Claims

1. An electric hair cutter comprising:

an electric motor including an output shaft;

a motion conversion mechanism that converts rotary motion of the output shaft into reciprocating linear motion; and

a movable blade driven by the reciprocating linear motion transmitted from the motion conversion mechanism, wherein

the motion conversion mechanism includes a first conversion portion, a second conversion portion, and an output portion,

the first conversion portion converts the rotary motion of the output shaft into reciprocating rotary motion about a first axis, wherein the first axis intersects with a direction parallel to the output shaft,

the second conversion portion converts the reciprocating rotary motion into the reciprocating linear motion,

the output portion couples the second conversion portion to the movable blade so that the movable blade performs the reciprocating linear motion,

the second conversion portion includes a motion transmission part, which couples the first conversion portion to the output portion, and an elastic deformation part, and

the elastic deformation part is coupled to the motion transmission part to restrict motion of the motion transmission part caused by motion components that are contained in the reciprocating rotary motion, which is transmitted from the first conversion portion to the motion transmission part, and differ from a motion component in an output direction, which is a direction of the reciprocating linear motion, so that the motion transmission part performs the reciprocating linear motion caused by the motion component of the output direction.

2. The electric hair cutter according to claim 1, wherein the first conversion portion includes

an eccentric shaft coupled to the output shaft so as to rotate about the output shaft at a position eccentric to the output shaft, and

an input conversion part coupled to the eccentric shaft to convert rotary motion of the eccentric shaft into the reciprocating rotary motion, and

the second conversion portion is coupled to the input conversion part to convert the reciprocating rotary motion of the input conversion part into the reciprocating linear motion.

3. The electric hair cutter according to claim 2, wherein

the input conversion part includes a first arm coupled to the eccentric shaft and a second arm extending from the first arm and coupled to the second conversion portion, and

the second conversion portion includes a restriction coupling part coupled to the second arm to allow the second arm to relatively move in a direction intersecting with the output direction and restrict relative movement of the second arm in the output direction.

4. The electric hair cutter according to claim 1, wherein

the motion conversion mechanism further includes a turning pair that couples the second conversion portion to the output portion, and

the turning pair includes

a rotation shaft having a second axis intersecting with the output direction, and

a coupling portion coupled to the rotation shaft to allow the second conversion portion and the output portion to relatively rotate about the second axis.

5. The electric hair cutter according to claim 1, further comprising a case that accommodates the electric motor and the motion conversion mechanism,

wherein the elastic deformation part includes a first part coupled to the case, a second part coupled to the motion transmission part, and an elastic part that couples the first part to the second part so as to elastically deform.

6. The electric hair cutter according to claim 5, wherein the elastic part includes a first elastic part and a second elastic part spaced apart from each other by a gap in the output direction.

7. The electric hair cutter according to claim 6, wherein the first axis is located between the first elastic part and the second elastic part.

8. The electric hair cutter according to claim 4, further comprising a case that accommodates the electric motor and the motion conversion mechanism, wherein

the elastic deformation part includes a first part coupled to the case, a second part coupled to the motion transmission part, and an elastic part that couples the first part to the second part so as to elastically deform,

the elastic part includes a first elastic part and a second elastic part spaced apart from each other by a gap in the output direction, and

the turning pair is located between the first elastic part and the second elastic part.

9. The electric hair cutter according to claim 3, wherein

the motion conversion mechanism further includes a turning pair that couples the second conversion portion to the output portion,

the turning pair includes

a rotation shaft having a second axis intersecting with the output direction, and

a coupling portion coupled to the rotation shaft to allow the second conversion portion and the output portion to relatively rotate about the second axis, and

the first conversion portion and the second conversion portion are configured so that the output direction extends parallel to a straight line that extends through the second axis and a coupled portion of the second arm and the restriction coupling part.

10. The electric hair cutter according to claim 1, wherein

the output portion includes a blade connector coupled to the movable blade, and

the electric hair cutter further comprises a guide that guides the blade connector in the output direction.