Cutter head for personal care appliances

Patent metadata

Field	Value
Publication number	US-10478980-B2
Application number	US-201715621014-A
Country	US
Kind code	B2
Filing date	Jun 13, 2017
Priority date	Jun 24, 2016
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

An electric shaver having a cutter head with a plurality of cutting rotors driven by a drive train connectable to a motor. The number of tooling rotors is significantly increased while at the same time the size of the tooling rotors is significantly reduced, thus being able to define an approximately smooth surface by the front faces of the tooling rotors.

First claim

What is claimed is:

1. A tool head for a personal care appliance, including a plurality of tooling rotors rotatably supported about rotor axes and a drive train for rotatably driving said tooling rotors from a motor, wherein the tooling rotors are separately displaceably supported to elastically dive along their axes of rotation into a retracted position against a biasing force provided by biasing devices onto said tooling rotors, said biasing devices being configured to allow for a diving travel of at least about ¼ of a diameter of a tooling rotor,
wherein said drive train includes:
an input crank element having connection means for connecting to a drive shaft, said input crank element being rotatably supported about a first crank rotation axis, wherein a first crank connecting pin is attached to said input crank element at a position eccentric to said first crank rotation axis, said input crank element having a first crank lever arm (h) defined by a distance between said first crank connecting pin and said first crank rotation axis;
a transmitter element configured to be driven by said input crank element; and
a plurality of output crank elements configured to be driven by said transmitter element to rotate about said rotor axis, said output crank elements being rotatably supported about second crank rotation axes and second crank connecting pins being attached to each of said output crank elements at a position eccentric to a respective one of said second crank rotation axes, wherein said output crank elements each have a second crank lever arm (h) defined by a distance between said second crank connecting pins and said respective one of said second crank rotation axes,
wherein said first and second crank rotation axes are parallel to each other and said first and second crank lever arms (h) have substantially a same lever length.

2. The tool head according to claim 1 , wherein said biasing devices are configured to allow for a diving travel greater than about ⅓ of the tooling rotors' diameter or greater than about ½ of the tooling rotors' diameter.

3. The tool head according to claim 1 , wherein in said retracted position, the tooling rotors are substantially flush with a functional tool head surface surrounding the tooling rotors, whereas in a projecting position, the tooling rotors have a height above said surrounding tool head surface of at least about ¼ of the tooling rotors' diameter.

4. The tool head according to claim 1 , wherein said drive train includes a drive pin portion for rotatorily driving said tooling rotors, wherein said drive pin portions each include a torque transmitting connector for slidably connecting to each of said tooling rotors to allow axial displacement and thus, diving of said tooling rotor relative to said drive pin portion under torque.

5. The tool head according to claim 4 , wherein said biasing devices are integrated into said drive pin portions and/or into said tooling rotors and/or wherein said biasing devices include spring elements acting between said drive pin portions and said tooling rotors.

6. The tool head according to claim 1 , wherein said plurality of tooling rotors include at least ten tooling rotors each having a diameter smaller than about 1/12 of a length of an enveloping line enveloping a rotor field defined by said tooling rotors.

7. The tool head according to claim 6 , wherein said plurality of tooling rotors include more than twenty or more than thirty tooling rotors each having a diameter of less than about 1/25 of the length of said enveloping line.

8. The tool head according to claim 1 , wherein each tooling rotor has a diameter of less than about 10 mm.

9. The tool head according to claim 1 , wherein a distance between neighboring pairs of tooling rotors is less than about 2 mm.

10. The tool head according to claim 1 , wherein said tooling rotors are arranged to define a rotor field having a rectangular or oval enveloping line.

11. The tool head according to claim 1 , wherein said tooling rotors are arranged in at least three rows, each row including at least three tooling rotors, wherein the tooling rotors in any two neighboring rows are offset relative to each other in the rows' longitudinal extension by half the distance between the centers of two neighboring tooling rotors in a row.

12. The tool head according to claim 1 , wherein the tooling rotors are arranged to define a rotor field having an enveloping area less than about 4/3 of the sum of front surface areas of the plurality of tooling rotors.

13. The tool head according to claim 1 , wherein the tooling rotors are arranged at different heights with respect to one another to define a rotor field surface having a convex and/or concave contour and/or a contour having concave and/or convex and/or flat sections.

14. The tool head according to claim 1 , wherein said transmitter element has a plate-like contour and/or a flat body with main extension axes transverse to the rotor axis, wherein said transmitter element includes a plurality of receiving recesses therein such as bores for rotatably receiving crank connection pins attached to the output crank elements.

15. The tool head according to claim 1 , wherein said transmitter element is supported only by the output crank elements, said input crank element, or a combination thereof.

16. The tool head according to claim 1 , wherein the transmitter element and the output and input crank elements are designed in terms of their mass (m) and their eccentricity (r) of their center of gravity from the rotation axis such that the centrifugal force of the transmitter element is compensated by the centrifugal forces of the input and output crank elements.

17. A personal care appliance comprising a tool head comprising a plurality of tooling rotors rotatably supported about rotor axes and a drive train for rotatably driving said tooling rotors from a motor, wherein the tooling rotors are separately displaceably supported to elastically dive along their axes of rotation into a retracted position against a biasing force provided by biasing devices onto said tooling rotors, said biasing devices being configured to allow for a diving travel of at least about ¼ of a diameter of a tooling rotor and a housing forming a handpiece and supporting said tool head,
wherein said drive train includes:
an input crank element having connection means for connecting to a drive shaft, said input crank element being rotatably supported about a first crank rotation axis, wherein a first crank connecting pin is attached to said input crank element at a position eccentric to said first crank rotation axis, said input crank element having a first crank lever arm (h) defined by a distance between said first crank connecting pin and said first crank rotation axis;
a transmitter element configured to be driven by said input crank element; and
a plurality of output crank elements configured to be driven by said transmitter element to rotate about said rotor axis, said output crank elements being rotatably supported about second crank rotation axes and second crank connecting pins being attached to each of said output crank elements at a position eccentric to a respective one of said second crank rotation axes, wherein said output crank elements each have a second crank lever arm (h) defined by a distance between said second crank connecting pins and said respective one of said second crank rotation axes,

wherein said first and second crank rotation axes are parallel to each other and said first and second crank lever arms (h) have substantially a same lever l

Assignees

• Braun Gmbh

Inventors

• Fischer Uwe
• Schuebel Christian
• Kluge Martin
• Fuellgrabe Martin

Classifications

• B26B19/14

  of the rotary-cutter type; Cutting heads therefor; Cutters therefor (B26B19/04 takes precedence) · CPC title

• B26B19/28

  Drive layout for hair clippers or dry shavers, e.g. providing for electromotive drive (electric motors per se H02) · CPC title

• B26B19/3886

  Actuating members, e.g. switches or control knobs · CPC title

• B26B19/32

  providing for mechanical drive, e.g. installation of a spring motor · CPC title

• B26B19/282 Primary

  Motors without a rotating central drive shaft, e.g. linear motors · CPC title