Personal care device

Patent metadata

Field	Value
Publication number	US-9919437-B2
Application number	US-201414428994-A
Country	US
Kind code	B2
Filing date	Oct 27, 2014
Priority date	Nov 5, 2013
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A personal care device comprising a main housing, a hair-cutting module displaceable with respect to the main housing against spring force in a direction parallel to a main axis, and a sensor comprising a first sensor unit connected to the main housing and a second sensor unit connected to the hair-cutting module. The hair cutting module is also tiltable in directions relative to the main housing. By measuring average displacement of the hair cutting module at multiple locations, the sensor is sensitive only to displacement parallel to the main axis. The sensor measures such displacement and determines the force needed to effect such displacement. If the force is larger than a predetermined value, a warning signal will be produced.

First claim

The invention claimed is:

1. A personal care device comprising:
a main housing disposed around a main axis;
a hair-cutting module that is displaceable relative to the main housing in a direction parallel to the main axis;
a spring arrangement disposed in the device for applying a predetermined spring force against displacement of the hair-cutting module in said direction parallel to the main axis;
a sensor arrangement comprising a first sensor unit connected to the main housing and a second sensor unit connected to the hair-cutting module for movement with said module;
the hair-cutting module also being rotatable relative to the main housing about at least one tilt axis extending perpendicularly to the main axis and against said predetermined spring force;
the first sensor unit including first and second sensory portions disposed at respective first and second locations relative to the main housing;
the second sensor unit including third and fourth sensory portions disposed at respective third and fourth locations relative to the hair-cutting module that are opposite to the first and second locations, respectively;
said first and second sensor units being adapted to move relative to each other during tilting of the hair-cutting module about the at least one tilt axis such that distances between the first and third sensory portions and between the second and fourth sensory portions will change, but the average distances between the first and second sensor units will remain unchanged; and
the sensor arrangement being adapted to be insensitive to said unchanging average distances during tilting but to be sensitive to said changes in displacement of the hair-cutting module relative to the main housing in the direction parallel to the main axis.

2. A personal care device according to claim 1 where, with respect to a plane extending through the main axis and the tilt axis, the first and the third location are located on a first side of said plane whilst the second and the fourth location are partly located in said plane or on a second side of said plane.

3. A personal care device according to claim 1 where the hair-cutting module is tiltable with respect to the main housing about two tilt axes extending perpendicularly to each other.

4. A personal care device according to claim 1 where the first sensor unit and the second sensor unit are arranged symmetrically around the main axis.

5. A personal care device according to claim 1 where the hair-cutting module comprises a number of cutting units, each cutting unit being provided with an external cutting element and an internal cutting element being rotatable about a rotation axis with respect to the external cutting element, wherein the rotation axes of the cutting units are located symmetrically around the main axis and each enclose an angle between 0 degrees and 15 degrees with the main axis.

6. A personal care device according to claim 5 where the hair-cutting module is connected to the main housing via a central shaft member which accommodates a main driving axle for commonly driving the internal cutting elements of the cutting units, and wherein the sensor arrangement is arranged symmetrically around said main driving axle.

7. A personal care device according to claim 1 , wherein the first sensor unit or the second sensor unit comprises a ring-shaped coil and the other of the sensor units comprises a plate influencing a magnetic field of the ring-shaped coil by a displacement of the second sensor unit with respect to the first sensor unit in a direction parallel to the main axis.

8. A personal care device according to claim 1 , wherein the first sensor unit or the second sensor unit comprises at least three Hall-sensor elements arranged at predetermined different locations around the main axis, and the other of the sensor units comprises at least three magnets, each magnet being arranged opposite a respective one of the Hall-sensor elements, seen in directions parallel to the main axis.

9. A personal care device according to claim 8 , wherein the Hall-sensor elements as well as the magnets are arranged at regular intervals around the main axis.

10. A personal care device according to claim 1 , wherein the hair cutting module comprises an intermediate part, which is provided with the second sensor unit, and a first hair cutting part, which is detachably connectable to the intermediate part, whilst the personal care device comprises a second hair cutting part which is different from the first hair cutting part, wherein by connecting the first hair cutting part to the intermediate part the second sensor unit is displaced into a reference position relative to the first sensor unit, or obtains a geometry or a material characteristic which is different from, respectively, a reference position, a geometry or a material characteristic obtained by connecting the second hair cutting part to the intermediate part.

11. A personal care device according to claim 10 , wherein the second sensor unit is displaced against spring force with respect to the intermediate part by connecting the first hair cutting part to the intermediate part.

12. A personal care device according to claim 10 , wherein the first hair cutting part is a hair shaving part and the second hair cutting part is a hair trimming or brushing part.

13. A personal care device according to claim 1 where a distance between the first and second locations is at least 25% of a distance between the first and the third locations.

Assignees

• Koninklijke Philips Nv

Inventors

• Veltman Eddy Gerrit
• Durksz Hedzer
• Ten Hove Matthijs Jaap Wolter
• Wind Liesbet Hillechina

Classifications

• B26B19/388 Primary

  Sensors; Control · CPC title

• B26B19/146

  Complete cutting head being movable · CPC title

• B26B19/14

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

• B26B19/38 Primary

  Details of, or accessories for, hair clippers, or dry shavers, e.g. housings, casings, grips, guards (cutters, cutting heads B26B19/04, B26B19/12, B26B19/14; cleaning or disinfecting devices A45D27/46; drying devices A45D27/48; casings for electric apparatus in general H05K) · CPC title