SKIN TREATMENT APPARATUS

Abstract

A skin treatment apparatus, preferably an epilator, comprising at least one detector for detecting approximation and/or contact with the skin and a control unit to actuate the device depending on the signal received from the detector. The control unit has at least one regulator which increases the speed of the drive unit upon detection of an increased resistance and/or current consumption by a sensor and/or decreases the speed of the drive unit upon detection of an decreased resistance and/or current consumption by a sensor.

Claims

1. A skin treatment apparatus comprising at least one application device for contacting the skin of a user, a drive unit for driving the at least one application device, a control unit for controlling movement of the at least one application device, and at least one detector for detecting approximation of the at least one application device to the skin or contact of the at least one application device with the skin, wherein the detector is coupled to the control unit for transmitting a signal to the control unit and wherein the control unit is designed and arranged such that it controls actuation of the drive unit or of the at least one application device depending on the signal received from the detector, wherein the control unit comprises at least one regulator for tuning the speed of the drive unit and in that the detector comprises a sensor measuring the resistance to actuation of the at least one application device or the current consumption of the drive unit, wherein the control unit is designed and arranged such that the at least one regulator increases the speed of the drive unit upon detection of an increased resistance or current consumption by the sensor and that the at least one regulator decreases the speed of the drive unit upon detection of an decreased resistance or current consumption by the sensor.

2. The apparatus in accordance with claim 1, wherein the sensor is designed and arranged to determine the current consumption of the motor of the drive unit in a given time interval, and that the control unit is designed and arranged to calculate a mean value using a given number of previous values of the current consumption, to compare the current consumption with the calculated mean value and a given threshold and to tune the rotational speed of the motor and to adapt the mean value depending on the result of the comparison.

3. The apparatus in accordance with claim 1, wherein the control unit comprises at least one switch for turning the drive unit on and off.

4. The apparatus in accordance with claim 1, wherein the detector comprises a mechanical detector, wherein the signal transmitted to the control unit is a movement of the mechanical detector or a transmission element coupled to the mechanical detector.

5. The apparatus in accordance with claim 1, wherein the at least one application device is displaceably or pivotably mounted in the apparatus, wherein displacement or pivoting of the at least one application device is transmitted to the control unit.

6. The apparatus in accordance with claim 1, further comprising at least one stimulation element, wherein the at least one stimulation element is displaceably or pivotably mounted in the apparatus, wherein displacement or pivoting of the at least one stimulation element is transmitted to the control unit.

7. The apparatus in accordance with claim 6, wherein the at least one application device or the at least one stimulation element is biased by at least one elastically deformable element, wherein the at least one application device or the at least one stimulation element is movable against the bias of the at least one elastically deformable element by a force applied by contacting the skin of a user with the at least one application device or the at least one stimulation element.

8. The apparatus in accordance with claim 6, wherein the at least one application device is coupled to a plunger acting on the control unit which plunger is connected to a yoke-spring, wherein the yoke-spring is set into movement by pivoting of the at least one application device about a swiveling axis.

9. The apparatus in accordance with claim 1, wherein the at least one application device is coupled to the drive unit via a slipping-clutch, wherein displacement of the at least one application device or pivoting of the at least one application device about a swiveling axis couples or de-couples the application device and the drive unit.

10. The apparatus in accordance with claim 1, wherein the detector comprises at least one of a pressure sensor, a proximity sensor, a heat sensor and a contact sensor.

11. The apparatus in accordance with claim 1, wherein the at least one application device comprises a plucking cylinder for removing hair from the skin of a user, wherein the plucking cylinder is driven by the drive unit to rotate about an axis.

12. The apparatus in accordance with claim 1, wherein the control unit comprises a timer and that the control unit is designed and arranged such that the at least one application device is driven by the drive unit for a defined time span after detecting removal of the at least one application device from the skin of a user.

13. An epilator comprising at least one plucking cylinder for contacting the skin of a user, a drive unit for driving the at least one plucking cylinder and a control unit for controlling movement of the at least one plucking cylinder, wherein the apparatus further comprises at least one detector for detecting approximation of the at least one plucking cylinder to the skin or contact of the at least one plucking cylinder with the skin, wherein the detector is coupled to the control unit for transmitting a signal to the control unit and wherein the control unit is designed and arranged such that it controls actuation of the drive unit or of the at least one plucking cylinder depending on the signal received from the detector.

14. The epilator in accordance with claim 13, wherein the detector comprises at least a pressure sensor or a sensor measuring the resistance to actuation of the at least one plucking cylinder or the current consumption of the drive unit.

15. The epilator in accordance with claim 13, wherein the control unit comprises at least one regulator for tuning the speed of the drive unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1a shows in a schematic sectional view an epilator according to a first embodiment of the invention in a switched off state,

[0032] FIG. 1b shows the epilator of FIG. 1a in a switched on state,

[0033] FIG. 2 shows a cut away view on an epilator according to a second embodiment of the invention,

[0034] FIG. 3a, 3b show a schematic sectional view of an epilator according to a third embodiment of the invention in a switched off state and a switched on state, respectively,

[0035] FIG. 4a, 4b show schematic sectional views of an epilator according to a fourth embodiment of the invention in a switched off state and switched on state, respectively,

[0036] FIG. 5a, 5b show in a schematic sectional view an epilator according to a fifth embodiment of the invention in a switched off state and a switched on state, respectively,

[0037] FIG. 6 shows in a cutaway view on an epilator according to a sixth embodiment of the invention,

[0038] FIG. 7 shows a cutaway view on an epilator according to a seventh embodiment of the invention,

[0039] FIG. 8 shows in a schematic sectional view an epilator according to an eighth embodiment of the invention, and

[0040] FIG. 9 shows a flow chart of the algorithm of the epilator of FIG. 8.

DETAILED DESCRIPTION OF THE INVENTION

[0041] The epilators depicted in FIGS. 1 to 7 and as described in the following may comprise a sensor measuring the resistance to actuation of a plucking cylinder or the like application device and/or the current consumption of a drive unit as described e.g. with reference to FIGS. 8 and 9. A control unit may be designed and arranged such that a regulator increases the speed of the drive unit upon detection of an increased resistance and/or current consumption by the sensor and that the regulator decreases the speed of the drive unit upon detection of a decreased resistance and/or current consumption by the sensor.

[0042] In the embodiment of FIGS. 1a and 1b a skin treatment apparatus in the form of an epilator 1 is shown comprising a body 2 or housing. A drive unit is provided within the body 2 comprising an, e.g. rechargeable, battery 3 and an electric motor 4. The electric motor 4 is coupled by a gearing 5 (cf. FIG. 2) to a plucking cylinder 6, i.e. an epilator drum with e.g. pincer-like clamping element for plucking and removing hair from a user's skin. The epilator 1 further comprises two stimulation elements 7 in the form of rollers provided on either side of the plucking cylinder 6. The stimulation elements 7 are held in an idle state as depicted in FIG. 1a with respect to the body 2 of the housing. The stimulation elements 7 may perform a swiveling movement with respect to the body 2 as can be taken from a comparison of FIG. 1a and FIG. 1b.

[0043] Switch 8 is provided interposed between the battery 3 and the electric motor 4 such that actuation of the switch 8 turns the electric motor 4 on and off. The switch 8 is connected to a yoke spring 9 and a further spring 10 which are arranged such that the switch 8 is open, i.e. turning the electric motor 4 off, when the epilator 1 is in its idle state as shown in FIG. 1a.

[0044] As the epilator 1 is approaching the user's skin indicated by line 11 in FIGS. 1a and 1b the stimulation elements 7 contact the skin 11 the epilator 1 may be tilted slightly as indicated by arrow 12 in FIG. 1b to bring both stimulation elements 7 as well as the plucking cylinder 6 located there between in contact with the skin 11. This tilting movement results in closing switch 8 by the movement of yoke spring 9 and spring 10. In other words, the epilator 1 is switched on to set plucking cylinder 6 in rotating motion by contacting the user's skin 11 and tilting the body 2 of the epilator 1 as shown in FIG. 1b. In other words, the stimulation elements 7 together with the yoke spring and the further spring 10 act as a detector for detecting approximation and/or contact of the plucking cylinder 6.

[0045] FIG. 2 shows a more detailed embodiment of the epilator 1 depicted in FIGS. 1a and 1b with a slightly amended design of the yoke spring 9 which includes the further spring 10. Stimulation elements 7 are omitted in the embodiment of FIG. 2 but may be provided if desired. In addition, FIG. 2 shows that switch 8 may be covered by a membrane 13 such that within body 2 the drive unit (battery 3 and electric motor 4) and the switch 8 forming a control unit are sealed in a water-proof manner.

[0046] An alternative embodiment of an epilator 1 is depicted in FIGS. 3a and 3b. In a similar manner as in the embodiment of FIGS. 1a and 1b the switch 8 (control unit) is actuated by the stimulation elements 7 acting as a detector. However, in the embodiments of FIGS. 3a and 3b it is mainly an axial displacement in the vertical direction as seen in FIGS. 3a and 3b which turns the epilator 1 on and off. In this respect, the stimulation elements 7 are mounted in the body 2 of the epilator 1 in a displaceable manner biased by springs 14. This results in the epilator 1 being switched off as long as the stimulation elements 7 are not in contact with the skin 11 as shown in FIG. 3a. However, if the epilator 1 is pressed against the user's skin 11 as shown in FIG. 3b such that the stimulation elements 7 are axially displaced against the bias of springs 14 until the plucking cylinder 6 contacts the skin, the switch 8 is closed, thereby turning the epilator 1 on.

[0047] The embodiment depicted in FIGS. 4a and 4b shows a similar alternative wherein the plucking cylinder 6 is the detector which together with a transmission arm opens or closes switch 8, thereby turning the epilator 1 on and off depending on the pressure applied to a user's skin by plucking cylinder 6. More detailed embodiments of this idea area shown in FIGS. 6 and 7, wherein only a small axial displacement of the plucking cylinder 6 of less than 1 mm is allowed in the embodiment of FIG. 6, while a larger axial displacement of more than 1 mm is allowed in the embodiment of FIG. 7.

[0048] A still further alternative is depicted in the embodiment of FIGS. 5a and 5b. In this embodiment the plucking cylinder 6 and component parts of the drive mechanism form a unit which is axially displaceable with respect to the body 2 of the epilator 1. Although the switch 8, the battery 3 and the electric motor 4 are indicated as being outside the body 2 in the schematic views of FIGS. 5a and 5b, these component parts may be provided within the body 2 of the epilator, preferably within the unit comprising the plucking cylinder which is axially moveable with respect to the body 2. Again, the switch 8 is closed by pressing the plucking cylinder onto the user's skin 11 to thereby activate the epilator 1.

[0049] FIG. 8 shows a schematic view of an epilator 1 with a motor 4 for driving a plucking cylinder 6. A sensor 16 (detector) is provided cooperating with a regulator 17 of the control unit, e.g. a speed governor, for measuring the load, e.g. by measuring the rotational speed of the plucking cylinder, the torque or the current consumption, for driving the plucking cylinder 6 and for setting a rotational speed of the drive unit by the regulator 17. For example, the regulator 17 of the control unit may be provided with a control algorithm regulating the rotational speed of the drive unit to a predefined value, while the control unit is configured to increase and decrease the rotational speed of the drive unit depending on the load. FIG. 9 shows an example of a flow chart of such an algorithm, wherein the drive unit is initially tuned to a low speed. If the sensor 16 of the control unit detects a change in the current consumption, the algorithm tunes the drive unit to a higher speed. As soon as the current consumption drops below a threshold value, the algorithm tunes the drive unit back to the lower speed.

[0050] In more detail, the sensor 16 determines the current consumption Imotor of the motor 4 every 10 ms. A mean value Imean is calculated using the last 16 values. The current consumption Imotor is compared with the mean value Imean and a predefined threshold offset_1. This threshold may be used to adjust sensitivity of changes in current consumption. If the change in current consumption exceeds the mean value Imean by the threshold offset_1, regulator 17 tunes the rotational speed of the motor 4 to a higher speed and adapts the mean value Imean. Reducing speed is effected in a similar manner using a second threshold offset_2. This algorithm has the benefit of not requiring an absolute threshold, thereby increasing sensitivity.

[0051] The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as 40 mm is intended to mean about 40 mm.

[0052] Every document cited herein, including any cross referenced or related patent or application and any patent application or patent to which this application claims priority or benefit thereof, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.

[0053] While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.