EP1979137B1 - Electrically operated shaver - Google Patents

Abstract

An electrically operated shaver includes a shaver housing and a cutter head. The cutter head is arranged on the shaver housing and includes at least one cutting device comprised of an outer cutter equipped with apertures and an under cutter. The cutters are driven into sliding relationship to one another by an electric drive, so that hairs entering the apertures are cut off by the cutting device. Provided on the cutter head adjacent to the cutting device is a supporting element which, like the cutting device, is engaged by an operator's skin surface during a shaving operation. Both the cutting device and the supporting element are mounted in the cutter head for displacement against the force of a spring. Means are provided for enabling a different distribution of the contact forces (F1, F2) to the cutting device and the supporting element.

Description

The invention relates to an electrically operated razor according to the features of patent claim 1.

From the US 5,398,412 An electric razor is already known in which the cutting head is mounted on an upper side of a shaving housing. The cutting head carries a head frame to which two outer cutters are attached. Two inner cutters are forced into forced contact with the outer cutters by means of a biasing spring and are oscillated to shave the hair relative to the outer cutters. The outer cutters may be brought into contact with different areas of a user's face to allow a more effective shave.

The head frame is held in a floating manner on the cutting head, so that the outer and inner cutting devices are depressed with him under compression of the springs. Thereby, the biasing forces of the springs are increased when the head frame is depressed. When a user wants to shave hard hair, the head frame is pressed down more firmly so that the biasing force, that is, the contact pressure between the outer and inner cutters, is increased. As a result, the hard hair with an increased contact pressure can be successfully cut off or sheared off. The deeper the head frame is depressed to increase the contact pressure, the more back pressure the skin receives from the outer cutters.

The back pressure is essential for shaving, but it should be kept within a tolerated range because too much back pressure can irritate the skin. This results from the fact that the skin penetrates too deeply into the holes of the external cutting devices, ie the upper knives, and the inner cutting devices, namely preferably two blade blocks, can injure the skin. However, when shaving hard hair with the floating head frame of the above patent, the head frame must be depressed deeply, resulting in an increase in back pressure. In other words, the shaving of the hard hair is made possible only after the head frame has been depressed deep or in the cutting head, but with the acceptance of the increased back pressure. Shaving soft hair, on the other hand, can be done almost without the head frame being pressed down and therefore with only a slight counterpressure on the skin.

Therefore, in order to reduce the irritation of the skin, it is highly desirable that the head frame exerts a reduced back pressure on the skin even in the case of shaving the hard hair with increased contact pressure between the outer and inner cutter.

From the DE 600 02 040 T2 Further, a razor is known which is capable of being uniformly depressed in different positions but with different contact pressures between the outer and inner cutters. In this case, the inner cutting devices, which are formed here by two juxtaposed blade blocks, set by an electrically driven motor in oscillating movements, so that they are formed because of their cutting or Scherkontaktes with the outer cutting devices here of upwardly curved shear sheets , Hair can shear off or cut off. The inner cutters are pushed up with a biasing spring so that a contact pressure is generated on the undersides of the shear sheets with which the inner cutters are pressed against the outer cutters.

The outer cutters are carried by a holder for the cutting devices, which is movably supported on a head frame mounted on top of the housing. In the razor, a height regulating mechanism for regulating the height of the head frame relative to the housing between a high position and a low position is included while the bias springs are more or less compressed to vary the contact pressure and to allow in that the holder for the cutting device can be pressed down relative to the head frame in both the upper and the lower position. Therefore, in addition to the fact that the outer cutters can be depressed even in the lower position when shaving hard hair, the shaving of hard hair can be realized in the lower position in which the increased contact pressure is available. However, in this case, the outer cutters are not held compressed relative to the head frame, and therefore, no increased back pressure is exerted on the skin, thereby allowing shaving of hard hair to be successfully performed with increased contact pressure but without irritation of the skin.

In other words, the increased contact pressure effective for shaving the hard hair can be initially adjusted without depressing the outer cutters, which would otherwise increase the back pressure on the skin. By contrast, shaving soft hair can be performed with a head frame held in the up position, allowing the outer cutters to follow the contour of the skin, but with less back pressure on the skin.

From the DE-A 103 44 564 is an electric shaver with a arranged between two shear foil applicator known which is submersible stored and elastically biased.

From the DE 102 46 519 A1 Furthermore, a razor is known, which has a movable cutting head with at least one cutting device for removing hair on a skin surface. The peculiarity of the invention here is that a detection device is provided for detecting a size that is related to the position of the cutting device relative to the skin surface. Furthermore, the invention consists of at least one actively confirmed adjusting device for changing the position of the cutting head and a control device for controlling the adjusting device, depending on the detected size. As a result, an optimal skin contact of each cutting element is to be achieved continuously. This is said to have a positive effect, in particular, when the razor has two or more cutting devices which should be in contact with the skin surface of an operator for optimal hair removal at the same time.

Object of the present invention is to improve the thoroughness of Haarentfemung during a shaving with the greatest possible skin protection.

This object is achieved by the features of claim 1. By the means according to the invention, a different distribution of the contact pressure on the cutting device and the support element, which is designed as a second cutting device whose upper diameter holes smaller cross-section than the upper blade of the first cutting device allows, so that the largest possible holes on the upper blade of the first cutting device can be used at the same time thin film. As a result, hair is threaded well into the larger holes of the shaving foil and there is a thorough shave even with slight pressure of the upper knife on the skin surface. To prevent the surface of the skin from increasing contact pressure is pressed deep into the holes of the upper blade, the contact pressure of the upper blade is changed according to the invention to the skin surface. This is not an attempt to influence the force with which the user presses the razor to the skin, but it is rather this contact pressure on the above upper blade, which is usually a shaving foil, and a second support element divided. This results in a better shaving performance with optimal skin care. It is advantageous if both the cutting device and the support element are movably mounted against the force of a spring in the cutting head.

According to the features of claim 3, the means consist of differently selected spring preloads of the springs on the cutting device and the support element, wherein the spring preload on the cutting device is greater than the spring preload on the support element. In this arrangement, the hole geometry of the cutting device can be chosen so that it is pressed against the skin surface to overcome the spring preload on the cutting device, while the support takes over virtually no support work up to this value. In this way, the shearing performance is optimized on the cutting device, while on the other hand, after overcoming the spring bias on the cutting device, the support element for receiving the contact pressure, whereby the penetration depth of the skin is braked in the holes of the cutter and kept in this way in limits.

According to the features of claim 4, the spring constant for the cutting device is smaller than the spring constant for the support element. It follows that the firmer the razor is pressed against the surface of the skin, the more the cutter and the support member must be supported by their springs. Due to the different spring constants but now makes the support a greater resistance than the cutting device and therefore takes over more shares of the contact pressure. This advantageously leads to a limitation of the skin penetration depth in the holes of the upper blade of the cutting device, so that the skin is spared more. Initially, however, the cutting device is pressed more strongly against the skin, but only up to an area that is tolerable to the skin. Due to the initial higher support of the pressing force on the cutting device relative to the support element, the cutting device is initially pressed more strongly against the skin, which strongly favors the cutting process. The firmer the skin pushes against the cutting device, the more force component is then transferred to the support element, so that the penetration depth of the cutting device into the skin no longer appreciably increases.

It is also conceivable to form more than two cutting devices on the cutting head, in which case the pair of identical hole geometry is adjacent. As a result, those cutting devices are always arranged side by side, which are formed with the same spring force and therefore can evenly lower even when force is applied. These then make the same support work over the other cutting devices, which also has a positive effect on the cutting result.

According to the features of claim 7, the cutting head is additionally pivotable about a pivot axis, so that, regardless of the different reduction of the cutting device and the supporting element or the second cutting device, the pressing forces F1, F2 can be influenced by the Verschwenkgrad of the cutting head. This solution relates in particular to the type of razor, as mentioned for example in the beginning under "Braun Synchro". However, if the cutting head is not pivotably mounted, but is stationary in the razor housing, then only the cutting device or the support element can be displaced in the cutting head.

According to the features of claim 8 in addition, the pivot axis of the cutting devices in the cutting head itself is displaced, whereby the fact can be taken into account that with operators who usually press the razor against the skin surface with a greater force, the cutting head is pivoted so in that a higher contact pressure is taken over by the cutting device with the smaller holes. For operators who usually push the razor with less force against the skin surface, the pivot axis in the cutting head can be pivoted so that the cutter with the larger holes absorbs more pressing force, which of course then on a higher penetration depth of the skin In the larger holes.

According to the features of claim 9 is in the lateral displacement of the pivot axis on the cutting head, the ratio of the two pressure forces acting on the upper blade and the lower blade, approximately reciprocal to the ratio of the two distances of the upper blade and the lower blade to the pivot axis.

While a purely mechanical Andruckregelung the size of the contact forces was released to the cutting devices by the features of claims 3 to 9, now according to the features of claim 11 and following the contact forces on the Cutting devices and the support to the skin surface additionally regulated by electrical / electronic means. For this purpose, at least one sensor formed on the cutting head and an electrical adjusting device and a microcontroller that detects the data from the force sensor and evaluates according to a predetermined scheme and then controls the actuator with electrical signals that held by pivoting the cutting head, the cutting device only a limited Contact pressure is exposed. By pivoting the cutting head, namely, the application of force can be more or less rolled onto the support element, so that the skin does not engage too deeply in the holes of the cutting device with a good shaving result.

Advantageously, the adjusting device is formed on the shaver housing, over which then the cutter housing pivotally mounted on the shaver housing is pivoted. For this purpose, it is advantageous if according to the features of claim 11 of the cutting device driving motor is formed in the cutting head itself. The cutting head is then pivotally mounted only on the shaver and preferably designed as a linear motor motor is connected via flexible electrical lines to the electrical connection in the shaver housing. The coupling device of the servomotor to the cutting head can be formed, for example, from a toothed belt arrangement or a toothed wheel consisting of gear arrangement, which causes the pivoting movement on the cutting head.

As a sensor may preferably be formed according to claim 12, a force sensor on the cutting device, the output measured data serve as a measure of the depth of penetration of the skin surface in the upper blade. Of course, a directly the depth of penetration of the skin into the holes of the foil measuring measuring arrangement, such as an optical or radiation-exerted sensor device, would be possible, but also the degree of contact pressure or the contact pressure on the cutter provides good information about the penetration of the Skin into the holes, if one has previously measured by means of experiments, the penetration depth in the laboratory at a given hole geometry of a foil in response to precisely defined contact forces.

An extremely practical solution results in a force sensor according to claim 13, which consists of a mounted on the cutter magnet on the one hand and a cutting head attached to the Hall sensor on the other hand, which is implemented by the Hall sensor, the distance travel of the magnet into electrical signals and these as a measure of the Serve size of the contact pressure.

According to the features of claim 14, the electronic pressure control solution according to claim 11 is particularly advantageous in that the support element is formed by a cutting device which corresponds in its embodiment of the first cutting device substantially, but with the difference to a smaller hole geometry and with at least a spring is formed which has a smaller spring bias than the first cutting device. To avoid repetition, we refer to the advantages of the features of the claim 6, which can also be used here. The electronic control of the contact forces is superimposed on the mechanical control by means of the spring forces, so that the control can be even more sensitive to increased pressure forces, without an operator must additionally intervene. The decisive advantage is also here that the cutting device with the larger holes at low contact forces takes over the main cutting performance and the skin does not engage too deeply in the larger holes.

According to the features of claim 15, it is also advantageous in this system, when the pair of cutting devices with the same hole geometry is always arranged side by side. Advantages are also found in the advantages of claim 7.

A lateral displacement of the pivot axis on the cutting head according to the features of claim 16 in turn changes the torques acting on the cutting head due to the changing contact forces, so that also the basic setting of a razor can be changed within small limits. Operators with a more robust skin shift the pivot axis in accordance with the 4 and 5 more to the right so that the cutter with the larger holes is more effective. People with softer skin take the other direction.

According to the features of claim 17, a further sensor is provided on the razor, which measures the razor speed. That is, the faster shaving, the less skin can penetrate into the larger holes of the first cutter and the later the cutter head must be pivoted so that the first cutter is relieved.

Advantageously, an optical sensor has proven to be a sensor for the razor speed according to claim 18, which is constructed in the same way as in the optical sensor a computer mouse is the case. Therefore, a closer description is not discussed here.

In addition to or instead of the speed sensor, according to the features of claim 19, a skin moisture sensor of the skin surface of an operator measuring sensor can be used on the cutting head, which also supplies the electronic control device with data, which ultimately cause the particularly moist skin Pressure force to the cutter with the larger holes can be greater than when the skin is very dry. For this purpose, according to the features of claim 20, the two resistors between the shear films of the two cutting devices are measured and fed to the microcontroller, which then pivots the adjusting device and thus the cutting head accordingly.

In addition to the speed sensor and the skin moisture sensor can still be formed according to the features of claim 21, a position of the shear films determining position sensor on the cutting head, which also provides information on whether softer skin parts - because they are more in the horizontal area - or harder skin parts - because this are more in the cheek, so in the vertical area - present. In the more horizontal position, the cutting head is rotated so that the cutter with the larger holes absorbs less pressing force, which reduces the penetration depth of the skin into the holes. Each of the individual sensors mentioned above may also be arranged alone or with one or even all of the razors.

Finally, even a friction sensor according to the features of claim 22 may be formed on the razor, which - similarly as the skin moisture sensor - also indirectly on the nature of the skin information, but additionally determines the influence of the contact pressure of the shaving head to the skin surface and the Microcontroller communicates. The larger the values on the friction sensor, the more the cutting head is pivoted so that the pressing force on the foil with the larger holes decreases. Advantageously, the friction sensor according to claim 23 is formed by a strain gauge, which is integrated in the shear foil.

Preferably, a mode switch can be formed on the shaver housing, via which the individual sensors are switched on or off. In addition, the mode switch can also be set to the "hard", "medium" or "soft" position, so that there enlarged (hard) or reduced (soft) by the penetration depth of the skin into the larger holes of the first foil.

Fig. 1

skizzenhafte Darstellung eines Längsschnittes eines elektrisch betriebenen Rasierers, bei dem im Schneidkopf zwei nebeneinander angeordnete Schneidvorrichtungen ausgebildet sind und die unabhängig voneinander im Schneidkopf verschiebbar sind,

Fig. 2

skizzenhafte Darstellung eines Längsschnittes eines gerade während eines Rasiervorgangs an der Hautoberfläche einer Bedienungsperson anliegenden Schneidkopfes, der über eine elektrisch steuerbare Stelleinrichtung schwenkbar an einem teilweise nur dargestellten Rasierergehäuse gelagert ist,

Fig. 3

schematische Darstellung eines Blockschaltbildes für eine elektrisch steuerbare Andruckregelung entsprechend dem Ausführungsbeispiel nach Fig. 2,

Fig. 4

skizzenhafte Darstellung eines weiteren Ausführungsbeispiels eines teilweise nur im Längsschnitt dargestellten und in einem Rasierergehäuse schwenkbaren Schneidkopfes, wobei zur Einstellung der Andruckverteilung die Schwenkachse des Schneidkopfes selbst im Schneidkopf beweglich gelagert ist und wobei die Schwenkachse in diesem Ausführungsbeispiel gerade ihre Mittelstellung gegenüber dem Schwenkkopf eingenommen hat,

Fig. 5

skizzenhafte Darstellung eines teilweise nur dargestellten Schneidkopfes gemäß Fig. 4, wobei allerdings die Schwenkachse nicht mehr mittig zu den Schneidvorrichtungen verläuft sondern mehr zu der linken Schneidvorrichtung hin im Schneidkopf verschoben wurde und

Fig. 6

schematische Darstellung eines Teilausschnittes eines weiteren Ausführungsbeispiels einer Schneidvorrichtung, bei der nur eine Feder sowohl für die Vorspannkraft des Untermessers an das Obermesser wie bei für das federnde Absenken von Obermesser und Untermesser bei einem Rasiervorgang sorgt.

Several embodiments of the invention are illustrated in the drawings and will be explained in more detail below. Show it:

Fig. 1

sketchy representation of a longitudinal section of an electrically operated razor, in which two juxtaposed cutting devices are formed in the cutting head and which are independently displaceable in the cutting head,

Fig. 2

sketch-like representation of a longitudinal section of a cutting head which is in contact with the skin surface of an operator during a shaving operation and which is mounted pivotably on a shaver housing partly shown by means of an electrically controllable actuating device,

Fig. 3

schematic representation of a block diagram for an electrically controllable pressure control according to the embodiment according to Fig. 2 .

Fig. 4

sketchy representation of a further embodiment of a partially shown only in longitudinal section and pivotable in a razor housing cutting head, wherein the adjustment of the Andruckverteilung the pivot axis of the cutting head itself is movably mounted in the cutting head and wherein the pivot axis in this embodiment has just taken its center position relative to the swivel head,

Fig. 5

sketchy representation of a partially only shown cutting head according to Fig. 4 However, although the pivot axis is no longer centered to the cutting devices but has been moved more towards the left cutting device in the cutting head and

Fig. 6

schematic representation of a partial section of another embodiment of a cutting device, in which only one spring provides both for the biasing force of the lower blade to the upper blade as for the resilient lowering of upper blade and lower blade in a shaving.

In Fig. 1 the razor 1 consists of a razor housing 2, in which one of an electric power source 3, here a battery, driven electric motor 4 is formed, which is connectable by an electrical on / off switch 5 with the electric power source 3. At the top 6 of the razor housing 2, a cutting head 7 is fixed, are mounted on the at least two juxtaposed cutting devices 8, 9 in the direction of movement X or Y to the razor housing 2 and away from it.

The cutting devices 8, 9 consist in the embodiments of the FIGS. 1, 2 . 4 and 5 essentially of a respective housing portion 10, 11, in each of which an inner cutter 12, 13 is formed. The inner cutting devices 12, 13 each consist of a blade block on which successively arranged individual blades 14, 15 are attached. The blades 14, 15 lie with their shear surfaces on the underside of the blades 14, 15 from the outside limiting upper blade 16, 17 at. In Fig. 1 However, between the blades 14, 15 and the upper blades 16,17 small distances to represent these parts better. The upper blades 16, 17 are curved upwards and run parallel in the vertical plane in the drawing. The same applies to the lower blades 12, 13. A tangent applied to the upper blades 16, 17 forms the cutting plane 54 for the razor 1 in the case of a very firm skin surface 29.

The blade blocks 12, 13 are pressed against the undersides of the upper blades 16, 17 via pretensioned springs 18, 19. The upper blades 16, 17 have a great many small holes 20, 21, of which only one hole 20, 21 has been shown as an example in the upper blades 16, 17 in a larger cross-section. In Fig. 1 are at the top of the cutting head 7 to the cross sections of the housing sections 10, 11 adapted openings 22 are formed, in which the housing sections 10, 11 are inserted flush and in which they can be slid according to the movement direction X, Y upwards or downwards , On the housing sections 10, 11 stops 23, 24 are formed, which limit the movement of the cutting devices 8, 9 upwards when they strike from below at the top 25 of the cutting head 7. On the underside of the housing sections 10, 11 engage springs 26, 27, which are supported on the other side on a wall 6 on the cutting head 7. The wall 6 should be in the sketchy FIG. 1 represent both the wall of the cutting head 7 as the wall of the razor housing 2. The springs 26, 27 push the cutting devices 8, 9 so far up until they strike with their stops 23, 24, at the top 25. The springs 18, 19 are used in Fig. 1 primarily to the lower blade 12, 13 with a spring bias to the underside of the upper blade 16, 17 to press. The springs 26, 27 are in Fig. 1 responsible for the lowering and the force distribution on both cutting devices, which will be explained later in more detail.

The electric motor 4 is connected via a mechanical transmission device 28 with the blade blocks 12, 13 and brings them into a fast oscillating motion, so that the blades 14, 15 at the holes 20, 21 of the upper blade 16, 17 a Create shearing motion and thus during shaving in the holes 20, 21 entering hair shear (not shown) or cut off.

Instead of the two acting on the cutting devices 8, 9 springs 18, 26 and 19, 27, only one spring 18, 19 can be used, as is made Fig. 6 is apparent. The springs 26, 27 are then responsible both for the pressing of the blade blocks 12, 13 to the outer diameter 16, 17 and for lowering the cutting devices 8, 9 at externally acting contact pressure F1, F2. In Fig. 6 is only the acted upon by the force F1 right cutting device 8 ( Fig. 1 ). Such a razor arrangement with two cutting devices 8, 9 and a central cutter separating them is known, for example, from the razor "Braun Synchro 7650", which has long been sold by the applicant, and is therefore only roughly explained here.

In this razor type, the two blade blocks 12, 13, of which, however, in Fig. 6 only the right blade block 12 is shown, resiliently and independently of one another in the movement direction X or Y to a foot 61 against the force of a spring 26, 27 slidably mounted. In the future only the one in Fig. 6 illustrated cutting device 8 received, since the second cutting device 9 with the exception of the biasing force and the spring rate of the spring 27 and the hole geometry of the upper blade 17 is otherwise identical.

From the bottom of the blade block 12 extends downwardly a guide rod 64 which penetrates a bore 61 formed in the foot 61 and which engages behind the bore by means of an extension 66 formed at its end. Due to the biasing force of the spring 26, it is supported on the one hand on the underside of the blade block 12 and on the other hand on the top 67 of the foot 61, so that the blade block 12 on the underside of the upper blade 16, here a very thin foil, is flush with a biasing force , The foot 61 and thus the blade block 12 is in turn fixed on the drive axle 62 of the drive motor 4 and clipped free of play. The upper blade 16 is slidably mounted in the direction of movement X in a removable frame 63, which in turn is releasably secured in the cutting head 7. The removable frame 63 has on both sides of the lower blade 12 guide means 69, in which the end portions of the upper blade 16 are guided in the direction of movement X. At the end portions of the upper blade 16 stops 70 are formed, which limit the direction of movement X in the removable frame 63.

In place of in the Fig. 1, 2 and 4 to 6 shown cutting system in the form of on upper blades 16, 17 back and forth sliding blade blocks 12, 13 can of course also a cutting system in the form of rotating cutting devices occur, in which then on the undersides of two juxtaposed, provided with holes upper blades ever a lower blade with a spring preload slidably rotates so that hair is cut off, if this over the holes of the upper blade to the lower blade reach. In this case, it is important that each individual cutting device, upon application of a contact force F1 or F2, descends into the cutting head after overcoming the biasing force, wherein the cutting device with the contact pressure F1 has larger holes than the cutting device with the force F2.

In the Fig. 1 and 2 are the springs 26, 27 biased between the top 6 and the housing sections 10, 11 with a certain spring preload and also have different spring constants. In Fig. 1 For example, the shaving foil 16 is provided with larger holes 20 than the holes 21 of the shaving foil 17. The spring 26 assigned to the housing section 10 has been selected in this exemplary embodiment such that the cutting device 8 only lowers with a force F1 after the upper blade 16 has been acted on. This force F1 is inventively greater than the force acting on the cutting device 9 force F2. According to the invention, however, then the spring constant of the spring 26 is smaller than the spring constant of the spring 27th

In a preferred embodiment, the spring 26 is lowered from a force of 3 Newton and then with a spring constant of 0.5 Newton per mm (N / mm). The spring 27, however, already dips at 0 Newton contact pressure, but then with a spring constant of 2 Newton per mm (N / mm). As a result, it is achieved according to the invention that it is possible to use the largest possible holes 20 on the shaving foil 16 at the same time as a thin foil. Because hair is known to engage in larger holes 20 better than in smaller holes 21. At the same time require larger holes 20 a lower contact pressure of the skin surface 29 on the upper blade 16 (shaving foil), which, however, according to the invention is only possible if the excess force on the support element or is transferred to the second cutting device 9, because this can accommodate more pressing force F2, because the upper blade 17 has smaller cross sections at the holes 21. In this way, in the same period of time, a more thorough and more gentle skin shave as in conventional razors arise.

In Fig. 1 is still a mechanical switch 30 shown, with which you can block both cutting devices 8,9 in their movement. Furthermore, with this switch 30, the biasing forces of the springs 26, 27 are changed, so that an earlier or later lowering of the cutting devices 8, 9 is possible. This is particularly advantageous if people press too hard against the skin surface 29. When adjusting the mechanical switch 30 then operates the razor 1 according to the invention more or less sensitive.

In Fig. 2 a razor 1 is shown only partially and also very sketchy. In contrast to Fig. 1 the cutting head 7 is rotatable about a pivot axis 31, which in the longitudinal direction of the cutting devices 8, 9 - that is perpendicular to the plane - runs. To avoid repetition will be in Fig. 2 only to the differences Fig. 1 received. On the corresponding same components is therefore not particularly discussed here.

In contrast to the razor 1 after Fig. 1 the electric drive motor 4 is no longer formed in the razor housing 2 but in the cutting head 7 and the cutting head 7 is pivotable about a pivot axis 31 via a drive belt 32 or otherwise a gear means, wherein the drive belt 32 is connected to a drive shaft 33 in the razor housing 2 at a drive motor (not shown) is attached. The outer surfaces of the shear sheets 8, 9 slide along a skin surface 29 on the chin bottom of the head 36 of an operator. Between the two cutting devices 8, 9, a central cutter 34 is still formed on the cutting head 7, which is connected via a transmission device 35 to the electric motor 4. Advantageously, the electric motor 4 is a linear motor, since it can be designed to be particularly compact and can therefore be easily integrated in a relatively small cutting head 7. Instead of the drive device 32, 33, which is shown in a very simple manner, it is also possible to use a gear arrangement or otherwise a well-known pivoting device, it is only important that the cutting head 7 be more or less at very short intervals as a function of certain variables which will be mentioned later its pivot axis 31 can be pivoted.

In Fig. 3 is a block diagram of an electronic Andrucksteuerregelung for the razor after Fig. 2 shown in principle. The core is a microcontroller 37 in which electrical impulses are received, processed and forwarded. For this purpose, two Andrucksensoren 38, 39 are present, of which the Andrucksensor 38, for example, the contact pressure F1 on the cutting device 8 and the Andrucksensor 39, the force F2 on the cutting device 9 measures and accordingly electrical signals via the lines 40, 41 to the microcontroller 37 forwards.

Finally, a skin sensor 42, or a speed sensor (not shown) may also be formed on the upper blade 16, 17, which likewise sends its electrical data to the microcontroller 37 via a line 43. Finally, a mode switch 44 may also be formed on the shaver housing 2, which sends its data via a line 45 to the microcontroller 37. Further sensors, such as a speed sensor 56, a position sensor 57 or a friction sensor 58 can be connected to the microcontroller 37 via electrical lines 71, 72, 73. They provide the microcontroller 37 with information about which conditions are currently present for the razor. In accordance with these states and depending on the contact forces F1 and / or F2, the adjusting device 47 and thus the cutting head 7 are then brought into the correct position for this data.

The microcontroller 37 is further connected via a line 46 with an electrically operated actuating device 47, which with the drive shaft 33 after Fig. 2 is coupled. From the microcontroller 37 via the line 46 outgoing signals go to the adjusting device 47, which then in turn according to the size and length of the signals, the cutting head 7 about the pivot axis 31 more or less pivots. The adjusting device 47 also has a servo position transmitter 48, which determines each position of the adjusting device 47 and conducts this electrical data via the line 49 to the microcontroller 37. The servo position transmitter 48 is connected via a line 50 to the servo drive or the adjusting device 47.

In 4 and 5 are still schematic representations of the upper portion of a razor 1 on an enlarged scale and shown only very sketchy from one side. In this case, extending on the shaver housing 2 on both sides of arms 51 (the second is not visible in the drawing) upwards, which are connected to each other via a pivot axis 52. Again, both the pivot axis 52 as the cutting head 7 extend perpendicular to the plane. The cutting head 7 is on the one hand in the counterclockwise direction on the pivot axis 52 pivotally and on the other hand it is simultaneously movable from left to right or vice versa according to the arrow 53 in a trained on the cutting head gate 59 (shown in phantom) laterally. Due to the lateral displacement of the cutting head 7 according to the arrow 53, the distance a and b changes, this being measured in each case from the center of the upper blade 16 or 17 to the pivot axis 52.

According to Fig. 5 The distance b was increased by the extent to which the pivot axis 52 has moved to the left with respect to the cutting head 7, while the dimension a is around this Has reduced amount. As a result, the torque attack on the cutting head 7 changes, so that the cutting head 7 rotates clockwise with the same application of force to the forces F1 and F2, than after the position of the cutting head 7 Fig. 4 the case is.

The mode of action of the razor 1 according to the invention FIG. 1 is the following.

After switching on the shaver 1 via the on / off switch 5, the electric motor 4 is supplied with power from the battery 3 or else an electrical energy source. The electric motor 4 sets via the mechanical transmission device 28, the blade blocks 12, 13 in a longitudinal direction of the lower and upper blades 12, 13 and 16,17 running oscillating reciprocating motion, the upper blade 16, 17 substantially fixed in the housing portion 10, 11 are arranged. In this case, the blades 14, 15 over the formed on the upper blades 16, 17 holes 20, 21, so that in the holes 20, 21 entering hairs (not shown) detected by these and sheared or cut off. As the upper blades 16, 17 slide along the skin surface 29 of an operator, a different contact force F1, F2 is applied to the cutters 8, 9 due to the unevenness of the skin surfaces 29 and the uneven pressing of the razor 1 against the skin surface 29. According to the invention, a lower blade 12 with an initially higher spring force is pressed against the upper blade 16 than is the case with the cutting device 9. In addition, the upper blade 16 of a cutting device 8 has a larger hole geometry than the upper blade 17 of the second cutting device 9. The hole geometry is to be understood that at least a portion or all holes 20 in diameter or cross section are larger than the holes 21 of the other Upper knife 17.

Assuming now that the cutting devices 8, 9 bear the same contact pressures, the upper blade 16 emerges at a predetermined contact pressure of F1, for example, equal to 3 Newton, and that then with a spring constant C1, due to the different spring preloads of the springs 18, 19 for example, 0.5 Newton per mm. The upper blade 17 with the smaller holes 21 already emerges at a lower pressure, for example at F2 of 0 Newton, but then with a spring constant C2 greater than the spring constant C1 of the spring 18, for example C2 equal to 2 Newton per mm. For smaller pressures up to 3 Newton makes the upper blade 16 with the larger holes 20, the greater shaving performance, because the hair can penetrate into larger holes 20 easier than in the smaller holes 21 of the upper blade 17th

Up to the predetermined value of, for example, 3 Newton, the upper blade 16 remains fully extended while the upper blade 17 with the smaller holes 21 has already submerged. For larger pressures of the razor 1 to the skin surface 29, however, the pressure of the upper blade 16 with the larger holes 20 only slightly increased, since then this outer blade 16 due to its lower spring constant C1 at the same force increase more than the upper blade 17 with the higher spring constant C2, which dips at a contact force greater than zero, but then the Abtauchweg decreases with increasing force. In this way, a thorough shave with the larger holes 20 having upper blade 16 is achieved and at the same time the skin is protected by the limited pressure, because it is not pressed so deep into the outer blade 16 into it.

In the above description of the operation of the razor 1 after Fig. 1 was spoken by a second cutting device 9. According to the invention, however, the second cutting device 9 may also be a pressing device, preferably a pressure roller (not shown), which runs parallel to the cutting device 8. When pressing against the skin surface 29 while the pressure roller behaves exactly as if there a second cutting device 9 would be present. The pressure roller has even the advantage that lower frictional forces during shaving through the skin surface 29 arise, however, in this system, only a single cutting device 8 is used, so that the cutting performance per back and heart movement of the razor 1 will be reduced.

The operation of the razor 1 according to the FIGS. 2 and 3 is the following: First, however, it must be mentioned that the two cutting devices 8, 9 can be constructed substantially the same as the cutting devices 8, 9 according to the Fig. 1 and 6 , but with the difference that the springs 26, 27 can also have the same or different preload forces and the same but also different spring constants C1, C2. With the same spring constants C1, C2, this has the consequence that, with the same contact pressure, both cutting devices 8, 9 equally lower with equal forces F1, F2. However, due to the electrical control of the cutting head 7 by the adjusting device 47 different contact forces F1, F2 generated on the cutting devices 8,9, by which the Hauteindringtiefe is affected.

In a first embodiment, only at the first cutting device 8 is a pressure sensor 38 (FIG. Fig. 3 ) (in Fig.2 not shown), which measures the pressure of the skin surface 29 on the cutting device 8. Since the upper blades 16, 17 as very thin shear foil are formed, it is difficult here directly to measure the penetration depth of the skin surface into the holes 20, 21. For this reason, a force sensor 38 is used whose electrical measurement data represent a measure of skin penetration depth.

The value measured at the force sensor 38 will decrease Fig. 3 supplied to the microcontroller 37 via the line 40. If the pressing force F1 is too high, the microcontroller 37 sends a signal to the electrically operated adjusting device 47, which pivots the drive shaft 33, the drive belt 32 and thus the cutting head 7 clockwise about the pivot axis 31, so that the cutting device 9 a higher contact pressure F2 experiences, which means that the contact pressure F1 is reduced. In turn, the pressure sensor 38 measures this reduction and sends a signal to the microcontroller 37, which stops the adjusting device 47. Decreases the contact pressure F1 below a predetermined level, which was communicated to the microcontroller 37 by the Andrucksensor 38, the actuator 47 is set in motion and the cutting head 7 is pivoted counterclockwise about the pivot axis 31 until the contact pressure F1 back to a certain Dimension has increased. In this way, a relatively constant application of force to the two cutting devices 8, 9 is achieved. Of course, the actuator 47 moves so fast that in a fraction of a second, the forces F1 and F2 adapt to the current state of shaving.

In a further embodiment, the cutting device 8 and the support element 9 can each have a pressure sensor 38, 39, so that the microcontroller 37 compares both values with one another and then controls the adjustment device 47 in accordance with an evaluation table such that the contact forces acting on the devices 8, 9 F1, F2 can be optimally divided between the two systems. If the application of force is too great, of course, the support element 9 takes over the largest share in order to protect the skin on the cutting device 8.

If two cutting devices 8, 9 are formed on the cutting head 7, of which the one upper blade 16 has larger holes 20 in cross-section than the holes 21 in the other upper blade 17, the distribution of the pressure forces on the two shear systems can be changed to one Pressure force F1 (less than 3 Newton), this force is supplied to the upper diameter 16 with the larger holes 20 substantially. If the pressure is increased by the user, the additional force in the ratio of the spring constant proportionally from the upper blades 16, 17 is added. For this purpose, the microcontroller 37 receives the data output by the pressure sensors 38, 39, evaluates them and controls the adjusting device 47 and thus the cutting head 7 accordingly.

As a further feature, the razor 1 can still be equipped with an electrically operated skin sensor 42. The skin sensor 42 measures the torque acting on the cutting head 7 pivotable about the pivot axis 31. The torque is converted by a servo generator 48 into electrical values, which are supplied to the microcontroller 37. On the basis of these data and the data of the Andrucksensoren 38, 39, the microcontroller 37 can determine or calculate a value and pass it to the adjusting device 47, which in turn pivots the cutting head 7 more or less in a rotational direction to the pressing forces F1, F2 in to bring specified permissible values. The servo current which is necessary on the adjusting device 47 in order to hold the cutting head 7 in a certain position is therefore a measure of the skin friction. For larger skin friction, therefore, the cutting head is pivoted so that the contact pressure F1 on the upper blade 16, which has the larger holes 20, is reduced. Of course, the skin friction can also be determined by means of a strain gauge which detects, for example, the deflection on the suspension of the shaving head or the stretching of a very thin shaving foil 16, 17. These values can also be supplied to the microcontroller 37, which then processes and compares this data accordingly and instructs the actuator 47 to bring the cutting head 7 into the correct position.

The razor 1 can also be provided with a mode switch 44, which communicates various requirements to the microcontroller 37 via the line 45 different requirements, such as in a first position "very sensitive skin", in a second position "sensitive skin" or in a third position "normal skin". These positions can also be called "gentle, aggressive or fast". In accordance with these positions, the microcontroller 37 will then control the adjusting device 47 such that the cutting head 7 assumes a position in which the cutting device 8 can absorb more or less pressing force F1.

The razor 1 may further be connected to a speed sensor 56, a position sensor 57 and / or a humidity sensor 58 via the lines 71, 72 and 73. To measure the shaver speed, the speed sensor 56 may be an optical sensor which may be constructed as the optical sensor in a computer mouse. Since the skin surface can penetrate deeper into the holes 20, 21 at very low speeds, in this case the cutting head 7 is pivoted in its basic setting by a predetermined fixed amount, so that the upper blade 16 with the larger holes 20, the pressure force generally by a fixed amount is reduced. For this purpose, the microcontroller 37 controls the adjusting device 47 and thus the cutting head 7 accordingly.

As a further sensor, a position sensor 57 may still be arranged in the razor 1, with which can be determined, for example, on the neck - here the razor 1 must be held rather vertically - or on the cheek - here, the razor must be kept more horizontal - shaved becomes. Since the skin on the neck is more elastic or sensitive than on the cheek, in this case, the cutting head 7 is pivoted so that the contact pressure F1 of the upper blade 16 is reduced with the larger holes 20.

Finally, a moisture sensor 56 measuring the skin surface 29 can still be arranged on the razor 1. The skin moisture can be done for example by measuring the electrical resistance between the two upper blades 16, 17. Since moist skin is more elastic than dry skin and thus penetrates deeper into the holes 20, 21 of the upper blades 16, 17, in this case the cutting head 7 is pivoted so that the pressing force F1 of the upper blade 16 is reduced with the larger holes 20.

The operation of the razor 1 according to the 4 and 5 is the following.

The pivot axis 52 is located centrally to the cutting head 7, ie, the distances a and b are the same size, the cutting head 7 remains approximately in a horizontal position, as in Fig. 4 to recognize, but only if the contact forces F1, F2 are the same. In order to let the distance b be greater than the distance a, you now move the pivot axis 52 according to Fig. 5 on the cutting head 7 in the gate 59 to the left. By means not shown in the drawing fastener is now attached to the axis 52 in the swivel head 7 so that it receives a fixed reference point relative to the arms. Now, if the cutting head 7 is acted upon by the same contact force F1, F2, so this pivots clockwise about the pivot axis 52, so that the upper blade 17 must absorb more pressing force F2, while the outer diameter 16 is relieved by this amount. In this case, the cutting devices 8,9 decrease correspondingly in the direction of movement X, Y as a function of the spring forces. In this way, a harder or softer shave can be performed.

The operation of the cutting device after Fig. 6 is the following.

First of all, however, it is mentioned that the cutting device 8 shown here can be arranged twice on a cutting head 7, as also in FIG Fig. 1 is shown and that the mode of action on both cutting devices 8, 9 and the mode of action in Fig. 1 so that it will not be discussed here again to avoid repetition. It will therefore only the functioning of in Fig. 6 presented and opposite Fig. 1 discriminating embodiment of the cutting device 8 received.

If the upper blade 16 is acted upon by a contact pressure F1, the upper blade 16 shifts downward in the direction X and presses the blade block 12 against the spring bias of the spring 26 down, the extension 66 from the stop 68 of the foot 61 lifts. The upper blade 16 is guided in the guide device 69 of the removable frame 63. Although in Fig. 6 the bore 65 has a lot of game play, so this is not the case in practice, since the connection of the drive shaft 62 to the blade block 12 must be rigid so that the oscillating movements without energy loss from the drive shaft 62 to the lower blade 12, 13 are transmitted.

As soon as the contact pressure F1 decreases, the spring 26 pushes the lower blade 12 and thus also the upper blade 16 upwards. Upper blade 16 and lower blade 12 are usually always flush with each other to always optimally ensure the shearing movement and thus the cutting pressure at the holes 20.

Claims (23)

1. An electrically operated shaver (1) comprising a shaver housing (2) and a cutter head (7) arranged on the shaver housing (2) on which cutter head is arranged at least one cutter assembly (8) consisting of an outer blade (16) with apertures (20) and an under blade (12), both of which are movable relative to one another by an electric drive (4), such that hairs entering the apertures (20) are cut off by the cutter assembly (8), wherein adjacent the cutter assembly (8) on the cutter head (7) a support element (9) is arranged, on which support element as well as on the cutter assembly (8) the skin surface (29) of a user is engaged during a shaving operation, and wherein means (18 and/or 26; 19 and/or 27; 52, 53) are provided that enable different distribution of contact forces (F1, F2) on the cutter assembly (8) and the support element (9), characterized in that the support element is designed as a second cutting device having an outer blade (17) with apertures (21) that have smaller cross-sections than the outer blade (16) of the first cutter assembly (8).
2. The shaver according to claim 1, characterized in that both the cutter assembly (8) and the support element (9) are movably mounted in the cutter head (7) against the force of a spring (18 and/or 26; 19 and/or 27).
3. The shaver according to claim 1, characterized in that the means is comprised of springs (18 and/or 26; 19 and/or 27) that operatively bear on the cutter assembly (8) and on the support element (9) under different spring biases, respectively, and in that the spring (18 and/or 26) bearing on the cutter assembly (8) has a greater spring bias than the spring (19 and/or 27) bearing on the support element (9).
4. The shaver according to claim 2 or 3, characterized in that the spring constant of the spring(s) (18 and/or 26) of the cutter assembly (8) is smaller than the spring constant of the spring(s) (19 and/or 27) of the support element (9).
5. The shaver according to claim 3, characterized in that the cutter assembly retracts only at a contact force (F1) of approximately 3 newtons, and that during the retraction the spring constant equals 0.5 newtons per mm, whereas the support element (9) already retracts at a contact force of 0 newtons, but which then exhibits a spring constant of 2 newtons per mm (N/mm).
6. The shaver according to any of claims 2 to 5, characterized in that the second cutter assembly (9) is also comprised of an outer blade (17) provided with apertures (21) and a blade block (13) comprising blades (15) biased into engagement with the outer blade (17), in that the blade block (13) also retracts against the force (F2) of a spring (27) when the outer blade (17) is depressed, in that the outer blade (16) of the first cutter assembly (8) has a smaller aperture geometry than the outer blade (17) of the second cutter assembly (9), and in that the first cutter assembly (8) has a greater spring bias than the second cutter assembly (9).
7. The shaver according to claim 1, characterized in that the cutter head (7) is pivotable about a pivot axis (31, 52) in the shaver housing (2), the pivot axis being disposed below a cutting plane (54) that is formed when the outer blade (16) is placed against the skin surface (29) during shaving, and in that the pivot axis (31, 52) extends parallel to the longitudinal direction of the outer blade (16) and the under blade (12).
8. The shaver according to claim 7, characterized in that a pivot axis (31, 52) is provided that may be displaced laterally on the cutter head.
9. The shaver according to claim 1, characterized in that the ratio of the two contact forces (F1, F2) acting on the outer blade (16) and the under blade (12) is approximately reciprocal to the ratio of the two distances (a, b) of the outer blade (16) and the under blade (12) relative to the pivot axis (31, 52).
10. The shaver according to claim 1, characterized in that the means is comprised of at least one sensor (38 and/or 39) arranged on the cutter head (7) and/or on the support element (9), in that the cutter head (7) is pivotable about a pivot axis (31, 52) in the shaver housing (2), in that the pivot axis (31, 52) extends parallel to the longitudinal direction of the outer blade (16) and the under blade (12), in that an electrically activated actuator means (47) is provided for pivoting the cutter head (7), and in that a microcontroller (37) serves to control the actuator means (47) in response to the values captured by the sensor (38 and/or 39).
11. The shaver according to claim 10, characterized in that a motor (4) is arranged on the cutter head (7) for driving the cutter assembly (8), in that the actuator means (47) is disposed outside of the cutter head (7) on the shaver (1), and in that a coupling device (32, 33) serves to couple the actuator means (33, 55) to the cutter head (7).
12. The shaver according to claim 10, characterized in that the sensor (38 and/or 39) is a force sensor, and in that the contact force (F1) serves as a measure of the depth of penetration of the skin surface (29) into the outer blade (16).
13. The shaver according to claim 12, characterized in that the force sensor (38 and/or 39) is comprised of a magnet mounted on the cutter assembly (8) on one hand and on the other hand of a Hall sensor mounted on the cutter head (7), in that the travel distance of the magnet is converted by the Hall sensor into electrical signals, and in that the electrical signals serve as a measure of the magnitude of the contact force (F1).
14. The shaver according to claim 10, characterized in that the second cutter assembly (9) is also comprised of an outer blade (17) provided with apertures (21) and a blade block (13) comprising blades (15) biased into engagement with the outer blade (17), in that the blade block (13) also retracts against the force (F2) of a spring (27) when the outer blade (17) is depressed, in that the outer blade (16) of the first cutter assembly (8) has a smaller aperture geometry than the outer blade (17) of the second cutter assembly (9), and in that the first cutter assembly (8) has a greater spring bias than the second cutter assembly (9).
15. The shaver according to claim 10, characterized in that more than two cutter assemblies (8, 9) are arranged in the cutter head, and in that each pair with like aperture geometry are arranged in adjacent relationship.
16. The shaver according to claim 10, characterized in that the pivot axis (31, 52) may be displaced laterally on the cutter head.
17. The shaver according to claim 10, characterized in that an additional sensor (56) may be arranged in the cutter head (7) for measuring the speed of the shaver, in that the additional sensor (56) is electrically connected to the microcontroller (37), in that the microcontroller (37) controls the actuator means (47) and the cutter head (7) in response to the values captured by the additional sensor (56) in such a way that a contact force (F1) that can act on the cutter assembly (8) is greater or smaller by a certain amount than the contact force that was set based on the value provided by the sensor (38 and/or 39).
18. The shaver according to claim 17, characterized in that the sensor (56) for measuring the speed of the shaver is an optical sensor.
19. The shaver according to claim 10, characterized in that an additional sensor (42) is arranged on the shaver (1) for measuring the moisture of the skin, in that the additional sensor (42) is electrically connected to the microcontroller (37), in that the microcontroller (37) controls the actuator means (47) and the cutter head (7) in response to the values captured by the additional sensor (42) in such a way that a contact force (F1) that can act on the cutter assembly (8) is greater or smaller by a certain amount than the contact force that was set based on the value provided by the sensor (38 and/or 39).
20. The shaver according to claim 19, characterized in that the sensor (42) for measuring the moisture of the skin is a measuring device that measures the electrical resistance between the two outer blades (16, 17).
21. The shaver according to claim 10, characterized in that a position sensor (57) is arranged on the shaver (1) for determining the position of the outer blade (16), in that the position sensor (57) is electrically connected to the microcontroller (37), in that the microcontroller (37) controls the actuator means (47) and the cutter head (7) in response to the values captured by the position sensor (57) in such a way that a contact force (F1) that can act on the cutter assembly (8) is greater or smaller by a certain amount than the contact force that was set based on the value provided by the sensor (38 and/or 39).
22. The shaver according to claim 10, characterized in that a friction sensor (58) is arranged on the outer blade (16) for measuring the skin friction, in that the friction sensor (58) is electrically connected to the microcontroller (37), in that the microcontroller (37) controls the actuator means (47) and the cutter head (7) in response to the values captured by the friction sensor (58) in such a way that a contact force (F1) that can act on the cutter assembly (8) is greater or smaller by a certain amount than the contact force that was set based on the value provided by the sensor (38 and/or 39).
23. The shaver according to claim 22, characterized in that the friction sensor (58) is comprised of a strain gauge, in that the friction sensor (58) is arranged on the cutter assembly (8), and in that the degree of deflection of the strain gauge is a measure of the magnitude of the friction force acting on the cutter head (7).

Images