Personal care device

Abstract

To provide a personal care device.SOLUTION: The invention relates to a personal care device, in particular a skin treatment device such as an electric shaver, comprising a housing forming an elongated handle for manually moving the personal care device along a body surface, a working head attached to said handle for performing a personal care treatment on said body surface, at least one detector for detecting at least one treatment parameter of said personal care device, and a feedback indicator for indicating feedback information to a user during the personal care treatment based on the detected treatment parameter. More specifically, such a feedback indicator includes a light emitter configured to emit a light signal onto a mirror in front of the user.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a personal care device, particularly a skin treatment device such as an electric shaver, including a housing forming an elongated handle for manually moving the personal care device along a body surface, a working head attached to the handle for performing a personal care treatment on the body surface, at least one detector for detecting at least one treatment parameter of the personal care device, and a feedback indicator for displaying feedback information to a user during the personal care treatment based on the detected treatment parameter. More specifically, such a personal care device may be a hair removal device such as an epilator or shaver, and such a shaver may be an electric shaver including at least one cutting unit, a drive unit for driving the at least one cutting unit, and a display device for displaying information. [Background technology]

[0002] Electric shavers typically have one or more cutter elements driven by an electric drive unit in an oscillatory fashion, where the cutter elements reciprocate under a shear foil; such cutter elements or undercutters may have an elongated shape and reciprocate along their longitudinal axes. Other types of electric shavers use rotary cutter elements that may be driven in an oscillatory or continuous fashion. The electric drive unit may include an electric motor or an electric linear motor, which may include a drive train with elements such as an elongated drive transmitter for transmitting the motor's drive motion to the cutter elements; the motor may be housed in the handle portion of the shaver, or alternatively in the shaver head.

[0003] Although such shavers are used by most users on a daily basis, it can be difficult to actually operate and handle the shaver perfectly. For example, even if the working head is pivotally supported to compensate for some angular displacement, the working head with the cutter elements can be pressed too hard against the skin, or the shaver can be held in an orientation that prevents the shear foil of the working head from full contact with the skin. Sometimes it is also difficult to move the shaver along the skin in the correct direction and at the correct speed relative to the relevant skin area. If the shaver offers a variety of different operating modes and complex functions, the proper use of the shaver becomes even more difficult.

[0004] For example, the drive unit of a shaver can sometimes be operated in different operating modes, e.g., in a fast or high-speed mode, the cutter speed or vibration frequency may be changed to improve shaving efficiency, while in a slow or low-speed mode, power consumption may be reduced. Depending on the shaver installation, other operating modes may be provided, including a long hair cutting mode or a fluid application mode in which a lubricant applicator such as a spray nozzle is activated.

[0005] To provide user feedback as to which operating mode has been selected, such shavers may have a display device for displaying information regarding such operating mode. For example, the selected cutter speed may be indicated, or the operation of functional accessories such as the fluid applicator or airflow generator described above may be displayed.

[0006] In addition to or instead of displaying such information regarding the operating mode, other information may be displayed by such a display device. For example, the charge state of the shaver's battery or accumulator may be indicated or the shaving time may be displayed; such additional information may also be displayed when the shaver or its drive unit is in an inactive state. For example, it has been proposed to extend the active state of the display for a period of several seconds after the shaver has been switched off, so that, for example, the battery charge level is displayed for several seconds after the shaver has been switched off, before fading out into an idle mode in which no information is displayed.

[0007] Although such display devices can provide some feedback information to the user, proper use remains difficult because such displays typically only inform the user of the selected operating option before and after the shaving process, and no feedback information is provided during shaving that can be communicated to the user to modify the shaving action.

[0008] To address such issues, it has been proposed to use audio and / or visual and / or haptic feedback information to guide the user in using the device appropriately.

[0009] For example, WO 2017 / 032547 A1 discloses a shaving device that provides acoustic and / or visual shaving instructions to a user, such as "apply gentle pressure to the user only" or "use a sensitive speed setting," based on usage data such as pressure and / or motion data measured by the shaving device. It is also suggested to take into account historical usage data to select an appropriate instruction from a list of stored instructions.

[0010] German Patent No. 196 01 780 (C1) suggests determining the pivot angle of the shaver head relative to the shaver handle when the shaver head reaches its maximum pivot position and providing an LED signal to warn the user that further angular displacement of the handle cannot be compensated. In addition to such an LED signal, it is mentioned that an acoustic or tactile warning signal may be provided, for example, regarding a change in the rotation speed of the motor that can be felt by the user.

[0011] WO 2015 / 165935 discloses a shaver having a feedback module that provides visual, audible, and / or tactile feedback to a user depending on the angular orientation of the shaver detected by an angular orientation sensor. The visual feedback may include a laser beam signal that displays a visible line on the part of the body being treated.

[0012] EP 2888086 B1 shows a shaver that generates an optical or acoustic warning signal when a user presses the hair-cutting members against the skin with excessive force, such excessive force being determined by measuring the axial displacement of the hair-cutting module relative to a handle that supports the module via a spring device.

[0013] EP 1549468 B1 describes a shaver that detects proper contact of the shear foil with the skin to be shaved, and states that such contact can be detected using an inductive sensor, a capacitive sensor, or an optical sensor that may include a light barrier directly above the shear foil. In the event of improper contact with the skin, it is suggested that the position of the shaver head relative to the handle be automatically changed by an actuator for pivoting or tilting the shaver head.

[0014] EP 3183992 A1 also suggests detecting proper skin contact of the shaver, with such contact being detected by a mechanical detector having a spring-loaded tracer pin and further by measuring the torque required to drive the cutter.

[0015] EP 3082020 A1 shows a shaver with different operating modes, the selected operating mode being indicated on a display unit showing the respective symbol.

[0016] DE 10 2010 023 681 (B4) discloses a shaver having an acceleration sensor for measuring the acceleration of the shaver due to manual handling thereof and for determining three-dimensional movement patterns as the cutters are switched on and off and the long hair trimmer is activated or deactivated.

[0017] EP 1165294 B1 discloses a shaver that measures the gripping force applied to the housing by the user's hand, and an LED emits green, yellow, and red light to indicate whether the actual gripping force is too low, average, or too high. The gripping force applied to the handle is assumed to indicate the force with which the shaver head is applied to the skin, and gripping the handle with excessive force indicates excessive pressure on the shaver head.

[0018] US 2002 / 0088121(A1) suggests a shaver with an LED display that indicates whether the user should shave faster or slower or use more shaving cream, the appropriate shaving speed being detected by an accelerometer and the use of shaving cream being detected by a microphone that detects shaving noise. [Prior art documents] [Patent documents]

[0019] [Patent Document 1] International Publication No. 2017 / 032547(A1) [Patent Document 2] German patent no. 196 01 780 (C1) [Patent Document 3] International Publication No. 2015 / 165935 [Patent Document 4] European Patent No. 2888086(B1) [Patent Document 5] European Patent No. 1549468(B1) [Patent Document 6] European Patent No. 3183992(A1) [Patent Document 7] European Patent No. 3082020(A1) [Patent Document 8] Patent Application Publication No. 10 2010 023 681(B4) [Patent Document 9] European Patent No. 1165294(B1) [Patent Document 10] U.S. Patent No. 2002 / 0088121(A1) Summary of the Invention [Means for solving the problem]

[0020] The object underlying the present invention is to provide an improved personal care device that avoids at least one of the drawbacks of the prior art and / or further develops existing solutions. A more specific object underlying the present invention is to improve the display of feedback information to the user.

[0021] A further object underlying the present invention is to improve the control of the information displayed to the user during shaving, without sacrificing easy handling of the shaver. More specifically, a self-explanatory and intuitive handling and use of the information functions of the shaver should be achieved.

[0022] A further object underlying the present invention is to provide an improved multi-purpose personal care appliance that provides users with different operating habits with appropriate operating guidance during use.

[0023] To achieve at least one of the aforementioned objectives, it has been proposed to transmit an optical signal from a personal care device to a mirror where a user would normally view the currently treated body surface to monitor the treatment process, so that the user can perceive the optical signal in the mirror that reflects the optical signal. To reach the mirror positioned in front of the user, the optical signal is emitted from the personal care device in a direction from the personal care device that is substantially perpendicular to the mirror in front of the user, using such a personal care device in a typical orientation. The handle of the personal care device is elongated, allowing for an intuitive grip, sometimes referred to as a "peeper grip," in which the thumb grasps the front of the handle and the other four fingers grasp the rear of the handle with the longitudinal axis of the handle extending across the fingers and / or substantially parallel to the first row of knuckles on the palm of the hand. The working head and lower end of the handle protrude from both sides of the gripping hand, and the central portion of the handle extends to the palmar side of the hand surrounding the central portion. The light emitter for emitting the light signal is configured to emit the light signal onto the mirror in front of the user, so that the user can see the light signal in the mirror when the personal care device is held in such a typical peer grip on the body surface to be treated.

[0024] More specifically, the feedback indicator comprises a light emitter configured to emit light from the end of the elongated handle and / or from the working head having a primary emission direction towards a bottom surface of the personal care device facing the working head, and therefore downwards when considering the personal care device in an upright position with the working head on top of it. In other words, since a user typically holds the body surface portion to be treated substantially parallel to and / or in front of the mirror to view such body surface portion in the mirror, the primary emission direction of light is towards the rear, away from the contact surface of the working head, and therefore substantially perpendicular away from the body surface portion to be treated.

[0025] According to a further aspect, the feedback information is adapted to the level of the detected treatment parameter so as to provide substantially a full range of feedback information to users with different operating habits. More specifically, the personal care device includes a calibration device for calibrating the relationship between the feedback information signal and the detected treatment parameter according to a user history of the detected treatment parameter. If the detection of the treatment parameter includes detection of a force with which the working head is pressed against the body surface to be treated, and the feedback information includes different pieces of information indicating a low force, an average force, and a high force, the controller for controlling the feedback information can be calibrated to issue information indicating the average force when the detected force corresponds to an average value of the detected force of the user history.

[0026] These and other advantages will become apparent from the following description, which refers to the drawings and possible examples. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a perspective view of an electric shaver including a handle and a shaver head connected thereto, the display device of the shaver including a display on the handle and a light emitter at its base. [Figure 2] 1 is a schematic diagram of the shaver's light emitter at the bottom of the handle that sends a light signal towards the mirror when the shaver is in use. [Figure 3] 3 is a schematic diagram of a shaver similar to FIG. 2 according to a further embodiment, in which the light emitter of the shaver is positioned at the top of the handle adjacent to the shaver head, and the light emitter transmits a light signal to a mirror used during shaving, similar to FIG. 1. [Figure 4] 3 is a schematic diagram of a shaver similar to FIG. 2 according to a further embodiment, in which the light emitter of the shaver is positioned in the shaver head, and the light emitter transmits a light signal to a mirror used during shaving, similar to FIG. 1. [Figure 5]10A-10C are schematic diagrams illustrating different functional relationships between the detected force on the skin and the color of the emitted light signal for calibrating the light emission of a shaver for users with different operating habits. DETAILED DESCRIPTION OF THE INVENTION

[0028] The personal care device provides a comfortable way to convey relevant information to the user, and according to one aspect, the user can easily perceive such information while using the personal care device. In contrast to a regular display on the housing, the user obtains information presented on a mirror in front of the user without having to look at the device housing or any other element of the device.

[0029] More specifically, according to a first aspect, the handheld personal care device is adapted to transmit a light signal to a mirror through which the user normally views the currently treated body surface to monitor the treatment process, so that the user can perceive the light signal in the mirror that reflects the light signal. To reach the mirror positioned in front of the user, the light signal is emitted from the personal care device in a direction toward the rear and / or bottom surface of the personal care device, and thus away from the working head and away from the body part where the working head is positioned for treatment. More specifically, the direction of emission is away from the personal care device substantially perpendicular to the mirror in front of the user when such a personal care device is held in a typical orientation for treating a user's body surface.

[0030] Because the handles of personal care devices are elongated, they offer an intuitive grip, sometimes referred to as a "peeper grip," in which the thumb grasps the front of the handle and the other four fingers grasp the rear of the handle with the handle's longitudinal axis extending across the fingers and / or substantially parallel to the first row of knuckles on the palm of the hand. The handle's working head and bottom end protrude from both sides of the gripping hand, with the handle's central portion extending on the palmar side of the hand surrounding the central portion. More specifically, shaver or epilator handles are typically grasped with the thumb positioned on the front side, where an on-off switch is located so that the thumb can operate the on-off switch; such an on-off switch is often located on one of the two larger surfaces of the substantially rectangular handle. If the device is equipped with a long hair trimmer on one side, the on-off switch is often located on the opposite side of the handle. Such a side with the on-off switch can be considered the front side of the handle.

[0031] The light emitter for emitting the light signal is configured to emit the light signal onto the mirror in front of the user, so that the user can see the light signal in the mirror when the personal care device is held in such a typical peer grip on the body surface to be treated.

[0032] More specifically, the feedback indicator comprises a light emitter configured to emit light from the end of the elongated handle and / or from the working head having a primary emission direction towards a bottom surface of the personal care device facing the working head, and therefore downwards when considering the personal care device in an upright position with the working head on top of it. In other words, since a user typically holds the body surface portion to be treated substantially parallel to and / or in front of the mirror to view such body surface portion in the mirror, the primary emission direction of light is towards the rear, away from the contact surface of the working head, and therefore substantially perpendicular away from the body surface portion to be treated.

[0033] The bottom of the handle may include an electrical connector for connecting the handheld device to a charging station and / or an electrical wire for charging a battery inside the handle. In either case, the bottom of the handle is the portion of the handle farthest from the working head. The bottom surface from which light is emitted refers to the space adjacent to the lower end of the handle. When the personal care device is in an upright position with the working head on top of it, the bottom surface is below the handle.

[0034] Advantageously, the light emitter may be configured to emit light towards the bottom surface as well as towards the rear side of the personal care device opposite the front side where the handle has an on / off switch, the main emission direction being inclined at an acute angle to the longitudinal axis of the elongated handle.

[0035] More specifically, the light emitter may be configured to have its main emission direction at an angle of between 80° and 10° or between 60° and 20° relative to the longitudinal axis of the handle.

[0036] Furthermore, the light emitter may be configured to emit the light for a 2x30° or 2x60° illumination beam with a substantially uniform light intensity across the cross section of the illumination beam.

[0037] More specifically, the light emitter may be configured to emit a substantially uniform bright cone or pyramid of light (if not circular in cross section) having a sufficiently large angle or divergence to allow sufficient perception of the light on the mirror, even when the angular position of the handle changes during processing. Advantageously, the emitted light may have a divergence angle between π and 3π, i.e., any intensity within the range of one-quarter to three-quarters of the full solid angle or full sphere (4π), not exceeding a factor of 100.

[0038] Furthermore, the light emitter may include multiple light sources of different light colors and / or at least one light source of variable light color, and a controller is provided to control the light emitter to vary the color of the emitted light in response to at least one detected process parameter.

[0039] To avoid shadowing of the light emitter by the hand gripping the handle, the light emitter can be located at an end of the handle outside the middle of the handle that forms the grip. In this regard, it should be noted that the handle has two ends that are not covered by the hand gripping the handle in its center. One end is the aforementioned bottom end farthest from the working head, while the other end of the handle is next to the working head. By providing the light emitter at the bottom, any shadowing by the gripping hand can be avoided. If the light emitter is located at the end next to the working head, it may be provided at a high position so that it can emit light toward the bottom surface above / over the fingers gripping the center of the handle.

[0040] Alternatively or additionally, the same or another light source may be positioned on the work head. In addition to the optical feedback described above, the feedback indicator may also provide acoustic information. Such acoustic feedback information may be provided via a loudspeaker. However, according to a further aspect, the sound representing the feedback information may be generated by varying the operation of a motor for driving a work tool of the work head.

[0041] To modify the motor sound, various options exist. More specifically, key motor output parameters such as amplitude and / or frequency and / or rotational speed can be modulated. Additionally or alternatively, additional sounds may be generated by the motor by mixing new signals into the motor's drive signal.

[0042] The feedback information may take into account various treatment parameters, and depending on the type of treatment, the personal care device may include various detectors for detecting such parameters.

[0043] More specifically, the device may include at least one of the following detectors: a force detector for detecting a force pressing the working head against a body surface; a touch detector for detecting contact of the working head with the body surface; a velocity and / or acceleration detector for detecting the velocity and / or acceleration of the personal care device; a rotation detector for detecting the rotation and / or orientation of the personal care device in three dimensions; a displacement detector for detecting linear and / or rotational displacement of the working head relative to the handle; a cutting activity detector for detecting cutting activity of the personal care device; and / or a trimmer position detector for detecting the position of the long hair trimmer.

[0044] The feedback indicator may be configured to provide feedback information in response to various process parameters detected during use of the personal care device. More specifically, the feedback information may be provided based on at least one of the following detected process parameters: force of pressing the working head against a body surface, contact of the working head with the body surface, velocity and / or acceleration of the personal care device, rotation and / or orientation of the personal care device in three dimensions, linear and / or rotational displacement of the working head relative to the handle, cutting activity of the personal care device, and position of the long hair trimmer.

[0045] The feedback indicator may indicate feedback information based on a current value of the at least one detected process parameter and / or based on a history of said values ​​of the at least one detected process parameter.

[0046] According to a further aspect, a calibration device is provided in the personal care device to enable rendering of substantially a full range of feedback information to users with different operating habits. More specifically, the personal care device includes a calibration device for calibrating the relationship between the feedback information signal and the detected treatment parameter in response to a user history of the detected treatment parameter. If the detection of the treatment parameter includes detection of a force with which the working head is pressed against the body surface to be treated, and the feedback information includes different pieces of information indicating a low force, an average force, and a high force, the controller for controlling the feedback information can be calibrated to issue information indicating the average force when the detected force corresponds to an average value of the detected force in the user history.

[0047] Such a calibration device may calibrate the feedback indicator based on a user history of the values ​​of the detected process parameters described above.

[0048] The calibration device may include an adaptive controller that adaptively controls the feedback indicator in response to at least one detected process parameter to provide different feedback information for different process parameters within a range of values ​​of the detected feedback parameter for that user history.

[0049] If the feedback indicator includes the aforementioned light emitters that emit light of different colors to provide the user with feedback information based on the light color, the adaptive controller can vary the functional relationship of the color of the light emitted by the light emitters to the detected force of the working head on the body surface and / or another detected processing parameter.

[0050] The personal care device may include a display on the shaver handle, which may include, for example, an LED display device or other suitable display type.

[0051] To achieve a space-saving display arrangement, the display device may include at least one display field, which is used to display information related to the operating mode as well as information related to other aspects of the shaver, such as the above-mentioned charge level, shaving time, cleaning status, or wear status. For example, such a display field may be configured to display a cascade or row of display dots or pictograms such as LEDs.

[0052] In addition to, or instead of, a display being provided on the electric shaver itself, a display may be provided on a cleaning and / or loading station configured to receive and / or be connected to the electric shaver in order to charge the shaver's battery and / or clean the shaver, where fluid may be applied to the shaver head for cleaning the shaver. Such a cleaning and / or charging station may include a display configured to communicate with the electric shaver at least when the shaver is docked in the station in order to display the information mentioned above. Additionally, if the shaver is provided with such a display / LED, it is advantageous to better recognize the signals provided by said display / LED. This is achieved by storing and holding the shaver in the cleaning tub of the cleaning / loading station essentially upside down (opposite the upright position of the shaver) so that the display on the rear of the head or handle is clearly visible.

[0053] These and other features will become apparent from the examples shown in the drawings. As can be seen from Figure 1, the shaver 1 may have a shaver housing forming a handle 2 for holding the shaver, which handle may have different shapes, such as a substantially cylindrical shape or a box-like or bone-like shape, which generally allows the shaver to be gripped ergonomically.

[0054] At one end of the shaver 1, a shaver head 3 is attached to a handle, and the shaver head 3 may be pivotally supported about one or more pivot axes.

[0055] The shaver head 3 includes at least one cutter unit 4, which may include a cutter element or an undercutter (which reciprocates under a shear foil). The shaver head 3 may also include a long hair cutter 8, as shown in FIG.

[0056] To drive such a cutter unit 4 and long hair cutter 8, a drive unit 5 may be received within the handle 2 and may include a motor that may be connected to the cutter unit 4 and long hair cutter 8 by a transmitter or drive train extending from the motor to the cutter unit.

[0057] As can be seen in Figure 1, an on-off switch or power switch 17 may be arranged on the handle 2, for example on the front side FS of the handle 2. By means of such a power switch 17, the drive unit 5 can be activated and switched off again.

[0058] As can be seen in Figure 1, the shaver 1 further comprises a display 18 which may be provided on the handle 2, for example on its front side. Such a display 18 may be part of a display device 6 which may further comprise additional electronic or other components such as a display controller 11, memory, power supply components, etc.

[0059] The display 18 can show various shaver parameters, such as, for example, on / off status or battery load status.

[0060] After such an initialization procedure, or in the alternative, the display 18 may display the battery level, where the number of cascading bars that are illuminated may correspond to the battery level.

[0061] As can be seen from FIG. 1, the shaver 1 may further comprise an input element 7 in the form of a touch button 16 which may for example be positioned in the vicinity of a power switch 17 .

[0062] While the aforementioned display 18 is useful for presenting information to the user before or after shaving, it is rather difficult to read information on such a display while shaving. To provide user guidance while shaving, the shaver 1 includes a feedback indicator 22 that presents feedback information on a mirror 70 in front of the user. As is well known, the mirror 70 is used when shaving the user's skin (see FIG. 2).

[0063] To present feedback information on the mirror 70, the feedback indicator 22 may include a light emitter 50 that may be positioned on the bottom 2b of the handle 2. As shown in FIG. 2, such bottom 2b typically protrudes from the hand gripping the handle 2 and is free of shadows cast by the hand. When the handle 2 is held in a "pipper grip" as shown in FIG. 2, the bottom 2b of the handle 2 extends toward the mirror 70, and the light emitter 50 may thus emit light 51 directly onto the mirror 70. Such light 51 may form an illuminating bundle, such as a light cone, having a divergence angle of at least 2×30°, or 2×45°, or 2×60°, or even 2×80° or more. The distribution of the emitted light 51 may be controlled by several optical systems or elements, such as lenses and / or reflectors associated with the light source. Advantageously, the light emitter 50 is configured to provide a substantially uniform light intensity and / or brightness over at least a significant portion of the illuminating bundle. For example, in the cross-sectional area having the lowest intensity, such intensity may be, for example, at least 25%, 30%, 45%, 50%, or 60% or more of the maximum intensity that can be imparted to the center of the luminous bundle.

[0064] As can be seen in FIG. 2, the emitted light 51 is returned to the user's eye by a mirror 70 so that the user can easily perceive the light signal.

[0065] 2, the light emitter 50 may be configured to emit light 51 having a main emission direction 52 away from the working head 3 and thus away from the user's skin. More specifically, the main emission direction 52 may be at an acute angle to the longitudinal axis LA of the handle 2 towards a bottom side BS of the handle and slightly inclined towards a rear side RS, which is the side of the handle opposite the front side FS, where the thumb may grip the handle 2 and / or an on / off switch may be provided.

[0066] The main radiation direction 52 may be inclined to the longitudinal axis LA of the handle at an angle of, for example, 10° to 40°, or 25° to 35°, or about 30°. Such an orientation of the main radiation direction 52 can compensate for the normal tilt of the handle 2 to the horizontal during normal operation, i.e., normal shaving.

[0067] 3, the light emitter 50 may also be located at the upper end portion 2h adjacent to the working head 3, or may be located at a raised portion of the handle so as to emit light 51 onto the fingers of the gripping hand and avoid shadows caused by the fingers when emitting light 51 backwards towards the bottom side BS. Nevertheless, the main emission direction 52 and the light distribution on the luminous flux may be as described above.

[0068] As can be seen from Figure 4, the light emitter 50 may also be positioned in the working head 3, in which embodiment the main emission direction 52 and light distribution over the light cone or luminous bundle may be as described above.

[0069] The light emitter 50 may be configured to emit light 51 of different colors, and advantageously, the light color may be adjusted in steps, gradually, or even continuously. More specifically, the light emitter 50 may be adjusted to emit light colors ranging from green to yellow to red, as shown by Figure 4. For example, the light emitter 50 may include multiple LEDs that emit different light colors, e.g., in an LED cluster.

[0070] Thus, the feedback information may be represented by different colored lights.

[0071] The feedback indicator 22, and therefore the aforementioned light emitter 50, is controlled by a control unit 80 which can vary the colour of the emitted light when the light emitter 50 is adjustable in colour.

[0072] Such a control unit 80 may take into account different process parameters detected by the multiple detectors during operation of the shaver 1. In addition, the control unit 80 may also be responsive to a history of the values ​​of the detected parameters, as will be explained in more detail.

[0073] Such detectors may in particular include a force detector 41 for detecting the force with which the working head 3 is pressed against the body surface 30. Such a force detector 41 may include various sensing means such as a sensor measuring the drag of the working head 3 against the handle 2, a sensor measuring bending stress in the handle, or a sensor measuring the torque and / or load of the motor driving the working tool, all of which are indicative of contact pressure.

[0074] Depending on the detected pressure or force with which the working head is pressed against the skin, the control unit 80 can change the color of the emitted light 51. For example, a green light may indicate a relatively low force, a yellow light may indicate an average force, and a red light may indicate a relatively high force. Advantageously, the color can be changed gradually or continuously to provide accurate feedback.

[0075] To accommodate a full range of colors for different users with different habits, the calibration device 60 can calibrate the relationship between color and detected force, as illustrated by FIG. 5 . Otherwise, a user who consistently applies a relatively high force would only receive feedback in the form of a red light, whereas a user who typically applies only a small amount of force would only receive feedback in the form of a green light. To avoid such unnecessary feedback situations, the calibration device 60 can take into account the user's history of detected force values. More specifically, the adaptive controller 61 can change the curve representing the relationship between light color and amount of force. For example, if the user history indicates a relatively high average force, the adaptive controller 61 can change the normal linear curve to one that maintains green and / or yellow light for higher force values, i.e., one of the right-hand curves in FIG. 5 . On the other hand, if the user history indicates a relatively low average force, the curve may be changed to already provide yellow and / or red light for lower forces (the left-hand curve in FIG. 5 ).

[0076] In addition to, or as an alternative to, the detection of the above forces, various other process parameters may be detected, and the above-described calibration device 60 may provide for calibration of the control functions of such other process parameters in a similar manner.

[0077] More specifically, the following detectors may be provided: a touch detector 42 for detecting contact with the body surface 30 of the working head 3; a speed and / or acceleration detector 43 for detecting the speed and / or acceleration of the personal care device, a rotation detector 44 for detecting the rotation and / or orientation of the personal care device in three dimensions; a displacement detector 45 for detecting the linear and / or rotational displacement of the working head 3 relative to the handle 2; a cutting activity detector 46 for detecting cutting activity of a personal care device; a trimmer position detector 47 for detecting the position of a long hair trimmer;

[0078] The shaver 1 may further be provided with a detection unit for detecting or measuring other parameters related to the process, such a detection unit may include a voltage and / or current detector for detecting the power consumption of the drive unit during shaving and / or a time measurement means for measuring, for example, the shaving time.

[0079] The control unit 80 may include a microcontroller 21 that may receive signals indicative of the parameters and analyze such signals to determine the process parameters, and a display means 22, such as the described lights 50, may be controlled by the microcontroller 21 to display feedback to the user. Additionally, such feedback information may be communicated to the charging and / or cleaning station.

[0080] The dimensions and values ​​disclosed herein should not be understood as being strictly limited to the exact numerical values ​​recited. Instead, unless otherwise indicated, 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 "approximately 40 mm."

Claims

[Claim 1] 1. A personal care device, in particular a skin treatment device such as an electric shaver (1), comprising: a housing forming an elongated handle (2) for manually moving the personal care device along a body surface (30); an operating head (3) attached to the handle (2) for performing a personal care treatment on the body surface (30); at least one detector (40) for detecting at least one treatment parameter of the personal care device; and a feedback indicator (22) for showing feedback information based on the detected treatment parameter to a user during the personal care treatment, characterized in that the feedback indicator (22) comprises a light emitter (50) configured to emit light (51) from end portions (2b, 2h) of the elongated handle (2) and / or from the operating head (3) having a main emission direction (52) towards a bottom side (BS) of the personal care device opposite the operating head (3), and therefore downwards when considering the personal care device in an upright position with the operating head (3) above the personal care device.

Images