EP1539437B1 - Small electrical appliance with a drive device for generation of an oscillating movement - Google Patents

Abstract

A small electric appliance with a drive mechanism for generating an oscillatory motion of at least one working unit of the small electric appliance. The drive mechanism has a first drive component, a second drive component and a coil for producing a magnetic field that extends from the first drive component and acts on the second drive component that is movably arranged in the small electric appliance, in such a way that the second drive component is set in an oscillatory motion. The first drive component is movably arranged in the small electric appliance in order to execute an oscillatory motion in phase opposition to the second drive component. The mass centers of gravity of the first drive component and the second drive component, including parts co-moving with the first drive component or the second drive component, move on a common straight line.

Description

The invention relates to a small electrical appliance with a drive device for generating an oscillating movement. The small appliance can be in particular a electric razor or an electric toothbrush.

From DE 1 151 307 A is a rocker armature drive for dry shavers with back and hergehender work movement of a Schermesserers known. The well-known oscillating armature drive has a firmly connected to the housing of the shaver and U-shaped trained electromagnet on. Near the pole of the fixed electromagnet are a work anchor and on both sides of the work anchor mass symmetry ever one swinging compensating anchor arranged. In operation, the work anchor swings, which drives the shearing blade, parallel to the pole faces of the electromagnet, wherein the Compensating anchor perform an antiphase oscillatory motion to a transmission the vibrations of the working anchor on the housing of the shaver as possible prevent.

DE 196 80 506 T1 discloses an electric shaver with an oscillating Linear motor, which has a stationary electromagnet and several moving components having, by means of the electromagnet in mutually opposite-phase oscillatory movements be offset. To the phase relationship of the moving components to each other Even under load, these are by means of a link mechanism connected to each other, the oscillation movement, reversing the direction transmits from one to the other mobile component.

From DE 197 81 664 C2 an electric shaver with a linear drive is known, the a hollow cylindrical stator having an electromagnetic coil. in the Stator two movable elements are arranged, which are driven in opposite phase to each other one of which drives a razor and the other one for suppression unwanted vibrations may have a counterweight.

The invention is based on the object with a small electrical appliance as possible optimal way to create an oscillating motion.

This object is achieved by the combination of features of claim 1.

The small electrical appliance according to the invention has a drive device for Generating an oscillating movement of at least one working unit of the electrical Small appliance. The drive device has a first drive component, a second drive component and a coil for forming a magnetic field from the first Drive component goes out and on the second drive component, which is movable in the small electrical appliance is arranged, acts in such a way that the second drive component in an oscillating movement is added. The invention is characterized in that the first drive component for executing an antiphase to the second drive component oscillating movement is movably arranged in the electric Kteingerät and that the centers of mass of the first drive component and the second drive component Included with the first drive component or the second drive component Moving components move on a common line.

The fact that the two drive components oscillate in phase opposition to one another significantly higher relative speed between the drive components achieved than at a conventional drive in which moves only a drive component and the other drive component rests. Since the efficiency of such drives with the Relative speed of the drive components increases each other, reaches the inventive Small appliance a higher efficiency than comparable known small appliances. Furthermore, the movement of the centers of gravity on a common line prevents the drive from generating an angular momentum and thereby unwanted Vibrations, for example, be transferred to the housing of the small device.

The small device can be designed according to the invention so that the pulses of the first Drive component and the second drive component included with the first drive component or the second drive component with moving components opposite are the same. This has the advantage that another source of undesirable Vibrations, namely a resulting linear pulse, are turned off can.

In a preferred embodiment, the first drive component and the second drive component comb-shaped into each other. This makes it possible, the drive device of the small device according to the invention form very compact and yet To achieve an angular momentum compensation and thus a favorable vibration behavior.

At least one of the two drive components may have one or more permanent magnets exhibit. Furthermore, at least one of the two drive components can be a winding core have, on which the coil is arranged. This can be at relatively small dimensions realize a powerful drive whose power consumption is sufficient is low, for example, to allow a battery operation of the small appliance according to the invention.

In the drive device of the small device according to the invention, at least one elastic Be provided element for generating restoring forces. This will be a formed oscillatory system, which is preferably operated under resonance conditions becomes. The elastic element is designed in particular as a leaf spring, which on the first drive component and is attached to the second drive component. The leaf spring thus counteracts a deflection of the two drive components relative to each other and has the advantage that it requires extremely little space.

Furthermore, it is advantageous if the first drive component and the second drive component are mechanically coupled together by at least one coupling element. This allows a strict adherence to the antiphase of the oscillatory movements the two drive components are ensured. In particular, the coupling element to the first drive component and to the second drive component in each case rotatable hinged. Depending on the geometry of the drive device perform the two drive components also a transverse movement, d. H. they move slightly transversely to the one described Vibration direction. It is therefore advantageous if the coupling element respectively to at least one of the drive components with play transverse to the direction of movement of Drive components is articulated. In a particularly simple manner can with the coupling element an antiphase between the two drive components made thereby be that the coupling element is rotatably mounted. In a preferred embodiment is the coupling element on a mounting axis for attachment of the drive device rotatably mounted on the small device according to the invention. This is possible Therefore, because the fulcrum of the coupling element does not move and thus an attachment is easily possible on the small appliance. The attachment axis can be eccentric between the articulation of the coupling element on the first drive component and on the be arranged second drive component. This has the advantage of being characterized very simple way and without additional gear different vibration amplitudes generate their relationship to each other even under load of the drive components does not change.

The invention will be described below with reference to the embodiments illustrated in the drawings explained.

Fig. 1

eine Prinzipskizze eines Ausführungsbeispiels für einen oszillierenden Line-armotor des erfindungsgemäßen Kleingeräts,

Fig. 2

eine Prinzipskizze eines weiteren Ausführungsbeispiels für einen oszillierenden Linearmotor des erfindungsgemäßen Kleingeräts,

Fig. 3

ein Ausführungsbeispiel für einen oszillierenden Linearmotor eines elektrischen Rasierers in perspektivischer Darstellung,

Fig. 4

das Ausführungsbeispiel aus Fig. 3 in einer perspektivischen Explosionsdarstellung,

Fig. 5

die beiden beweglichen Motorkomponenten des Linearmotors aus Fig. 3 als separate Einheiten in einer perspektivischen Darstellung und

Fig. 6

die beiden Motorkomponenten aus Fig. 5 in zusammengefügtem Zustand in perspektivischer Darstellung.

Show it

Fig. 1

a schematic diagram of an embodiment of an oscillating line armotor of the small device according to the invention,

Fig. 2

a schematic diagram of another embodiment of an oscillating linear motor of the small device according to the invention,

Fig. 3

an exemplary embodiment of an oscillating linear motor of an electric shaver in perspective view,

Fig. 4

3 shows the embodiment of FIG. 3 in a perspective exploded view,

Fig. 5

the two movable motor components of the linear motor of FIG. 3 as separate units in a perspective view and

Fig. 6

the two engine components of Fig. 5 in assembled state in a perspective view.

To explain the principle underlying the invention, the strong first abstracted embodiments of FIGS. 1 and 2 used. Then it will open the embodiment of an electric shaver illustrated in FIGS. 3 to 6 with an oscillating linear motor, where both the figurative representation as well as the associated description limited to the drive system of the razor are. The other training of the razor can be done in the usual way and is not specifically described.

Fig. 1 shows a schematic diagram of an embodiment of an oscillating linear motor of the small device according to the invention. The linear motor has two movable engine components 1 and 2, which are arranged at a small distance from each other. The first engine component 1 consists of a rod-shaped iron core 3 and a wire wound coil 4. The second motor component 2 has two pairs of Permanent magnet 5 on. The permanent magnets 5 of each pair are each in antiparallel oriented polarity arranged side by side on a common support plate 6. The Support plate 6, like the iron core 3 made of a ferrous material and is U-shaped educated. As indicated in FIG. 1, the carrier plate 6 can optionally be designed as a closed, rectangular frame may be formed to reduce stray magnetic fields. The following description refers to a U-shaped design of the carrier plate 6, however, can be analogously transferred to a training as a framework. The permanent magnets 5 are respectively on the inner sides of the two legs of the U-shaped support plate 6 attached. Between the opposite pairs of permanent magnets 5 is the Iron core 3 arranged such that between the two end faces of the iron core 3 and the respective adjacent pair of permanent magnets 5 is an air gap 7. Near the end faces are attached to the side of the iron core 3 two springs 8, which are parallel to the Legs of the support plate 6 extend to the bottom and there also attached are. The first engine component 1 and the second engine component 2 are movably suspended, so that they move parallel to the legs of the support plate 6, d. H. in the representation of Fig. 1 can perform a movement in the horizontal direction. Under Considering the springs 8 results in a vibratory system in which the first engine component 1 and the second engine component 2 each have a linear one Perform vibration movement. The directions of movement of the two engine components 1 and 2 are each opposite each other, d h. the vibrations are lost out of phase with each other.

An essential aspect of the invention is that the center of gravity of the first engine component 1 and the second engine component 2 on a common Moving straight lines. This means that from the movement of the two engine components. 1 and 2 no angular momentum results. To the said condition for the movement of the centers of mass to meet, the two engine components 1 and 2 in the in Fig. 1 illustrated embodiment each formed symmetrically and also symmetrical arranged to each other. The physical symmetry in the training or in the arrangement the engine components 1 and 2 is not mandatory. If, in addition, the in the context of the movement of the two engine components 1 and 2 occurring linear Pulses of the engine components 1 and 2 are the same as each other at any time, generates the linear motor in a suspension carrying him, for example, the housing an electric shaver, no vibrations.

In the illustration of Fig. 1, the linear motor is in its equilibrium position, d. H. the springs 8 are neither stretched nor compressed. Without the influence of external forces remain the engine components 1 and 2 in this position, as for a deflection in horizontal Direction of the springs 8 generated restoring forces must be overcome. If it comes by a force to a deflection of the two engine components. 1 and 2 relative to each other, so is by the restoring forces generated by the springs 8 a Driven back to the equilibrium position. To those needed for a deflection To generate force, a current flow through the coil 4 is produced. The coil 4 acts as Electromagnet and generated by the iron core 3 generates a magnetic field on the Permanent magnets 5 acts and a relative movement between the coil 4 and the permanent magnet 5 result. In the illustration of FIG. 1, the relative movement is horizontal Direction. By appropriate control that can be generated with the coil 4 Be reversed magnetic field, so that the first and the second engine component. 1 and 2 are offset in opposite phase to each other. There is one essential Aspect of the invention in that both the first engine component 1 as also moves the second engine component 2, d. h., that the linear motor has no stator, with the help of a runner is driven, but two oscillating against each other Engine components 1 and 2, which drive each other. One of these engine components 1 or 2 corresponds to the rotor of a conventional linear motor. The other takes over the functions of the stator of a conventional linear motor, but is in contrast to this not static, but also moves. This leads among other things also to ensure that under otherwise identical conditions, the first and second engine component 1 and 2 of the linear motor according to the invention with a relative speed to each other move twice the relative speed between a stator and a rotor of a conventional linear motor. This can be in the inventive Linear motor achieve a relatively high efficiency.

The frequency of the oscillatory motion of the two engine components 1 and 2 is about set the control of the coil 4 and in particular adjusted so that they the resonance frequency the vibration system corresponds, by the two engine components 1 and 2 and the springs 8 is formed. Under resonance conditions results very robust vibration behavior and it is only a comparatively low energy input required.

Fig. 2 shows a schematic diagram of another embodiment of an oscillating Linear motor of the small appliance according to the invention. In this embodiment, the Iron core 3 is formed as a rectangular frame, in which one side of a breakthrough 9 has. The three remaining sides of the frame are designed and worn throughout one coil 4, so that a total of three coils 4 are present. In the breakthrough 9 is arranged a pair of antiparallel-oriented permanent magnet 5, the overall rod-shaped is formed, wherein the permanent magnets 5 in turn through air gaps 7 from the iron core 3 are separated. Between the breakthrough 9 opposite side of the iron core 3 and the permanent magnet 5, the spring 8 is clamped. Furthermore, the permanent magnets 5 via two struts 10, each of which overcome one of the air gaps 7, with the iron core. 3 mechanically coupled. For this purpose, each strut 10 has a first bore 11 and a second Bore 12 for the rotatable articulation of the iron core 3 and the permanent magnet. 5 on. Furthermore, each strut 10 in the area between the first bore 11 and the second bore 12, a third bore 13 for attachment of the linear motor, for example on a figuratively not shown housing. In addition to serve this attachment function the struts 10 to the two engine components 1 and 2 with each other in terms of movement to pair. This coupling causes the two engine components 1 and 2 at any time move exactly in opposite phase to each other, since the engine mount each spatially between the articulation on the first engine component 1 and the articulation takes place on the second engine component 2. In other words, when in the presentation 2, the first motor component 1 moves to the left, moves simultaneously the second engine component 2 to the right and vice versa. Because in this movement the Distance between the points of the linkage at the two engine components 1 and 2 varies slightly, the holes 11 and 12 are formed as slots, so that the Linkage with a certain play takes place.

A special feature of the illustrated embodiment is that the third bore 13 not centrally between the holes 11 and 12, but closer to the first hole 11 is arranged for articulation on the iron core 3 of the first engine component 1. This has the consequence that the two engine components 1 and 2 with different Oscillation amplitudes swing. In the illustrated geometry results for the first Engine component 1 a smaller oscillation amplitude than for the second engine component 2. The speeds at which the two engine components 1 and 2 move, behave accordingly inversely to each other. So that the linear pulses of the both engine components 1 and 2 opposite in this embodiment can assume the same values, the first engine component 1 is executed so that they has a larger mass than the second engine component 2. This geometry can be For example, use in an electric shaver, in which one or more shearing blades should perform fast oscillatory movements with large amplitude and a Shaving head to oscillate in phase opposition with small amplitude. This is the shearing blade or the shearing blades are driven by the second motor component 2 and the shaving head of the first engine component 1.

Fig. 3 shows an embodiment of an oscillating linear motor of an electric Razor in perspective view. An associated exploded view is shown in FIG. 5 displayed. Apart from the linear motor itself, there are only a few components of the razor represented, which are connected directly to the linear motor. The better one For clarity, a representation of the shaving head was also omitted. The others Training of the razor can be done in a conventional manner. For the description the designations according to FIG. 2 are used for components corresponding to each other, wherein the specific configuration of the components and also of the entire linear motor partly deviates considerably from Fig. 2.

The linear motor is mounted on a base plate 14 fixed to a non-figured Housing of the razor is connected. In the base plate 14 are two stepped Bolt 15 inserted, which are guided by the third holes 13 of the struts 10. About four pierced bearing blocks 16, the two engine components 1 and 2 are rotatable hinged to the struts 10. For this purpose, two pins 17 are provided on each strut 10, on which the bearing pads 16 are attached, each with a certain play between the Pin 17 and the holes 11 or 12 of the bearing blocks 16 is. From the two storage blocks 16, each plugged onto a strut 10, is one on the first motor component 1 and the other attached to the second engine component 2. Through this Arrangement, the two engine components 1 and 2 are suspended so that they are within certain limits can move parallel to the longitudinal side of the base plate 14. The Both engine components 1 and 2 are formed by a total of four leaf springs Springs 8 connected to each other, by the deflection from the illustrated equilibrium position Restoring forces are generated. With the first engine component 1 and the second engine component 2, a shearing blade 18 is fixedly connected, so that the two Shearing blades 18 are driven in opposite phase to each other. As further components The illustrated embodiment of the linear motor, the iron core 3 with the coil 4 and the permanent magnets 5 on and a number of other components in the frame of the invention are not of particular interest and therefore not closer will be received.

FIG. 5 shows the two motor components 1 and 2 of the linear motor from FIG. 3 as separate ones Units in a perspective view. In Fig. 6, the two engine components 1 and 2 shown together. In a comparison with Figs. 3 and 4, it should be noted that in order to illustrate further details in Figs. 5 and 6, a back View is shown, d. H. the object shown is about a vertical axis Turned 180 °.

As is apparent from Figs. 5 and 6, the two engine components 1 and 2 are constructed so that that they mesh together like a comb. This makes it possible for the linear motor very much form compact and yet the already mentioned angular momentum compensation to reach, d. H. to make the mass distributions of the two engine components 1 and 2 so that their centers of mass move on a common line. there It is easily possible, even the masses of the two engine components. 1 and 2 driven shear blades 18 and optionally a driven shaving head included. In the illustrated embodiment, the engine hitch succeed to the Bolt 15 each centrally between the linkage to the first engine component 1 and the second engine component 2. Thus, the two engine components 1 and 2 move with the same amplitude and same speed. By balancing the masses of the two engine components 1 and 2 each including mitbewegter components Also, the linear pulses can be compensated and thus a low-vibration Razor can be realized.

Claims (13)

1. A small electric appliance with a drive mechanism for generating an oscillatory motion of at least one working unit (18) of the small electric appliance, said drive mechanism having a first drive component (1), a second drive component (2) and a coil (4) for producing a magnetic field that extends from the first drive component (1) and acts on the second drive component (2) that is movably arranged in the small electric appliance, in such a way that the second drive component (2) is set in an oscillatory motion, characterized in that the first drive component (1) is movably arranged in the small electric appliance in order to execute an oscillatory motion in phase opposition to the second drive component (2), and the mass centers of gravity of the first drive component (1) and the second drive component (2), including parts co-moving with the first drive component (1) or the second drive component (2), move on a common straight line.
2. The small electric appliance as claimed in claim 1, characterized in that the momentums of the first drive component (1) and the second drive component (2), including parts co-moving with the first drive component (1) or the second drive component (2), are opposite and equal.
3. The small electric appliance as claimed in any one of the preceding claims, characterized in that the first drive component (1) and the second drive component (2) are in meshing engagement with one another.
4. The small electric appliance as claimed in any one of the preceding claims, characterized in that at least one of the two drive components (1, 2) has at least one permanent magnet (5).
5. The small electric appliance as claimed in any one of the preceding claims, characterized in that at least one of the two drive components (1, 2) has a core (3) around which the coil (4) is wound.
6. The small electric appliance as claimed in any one of the preceding claims, characterized in that provision is made for at least one elastic element (8) for producing restoring forces.
7. The small electric appliance as claimed in claim 6, characterized in that the elastic element (8) is constructed as a leaf spring that is fastened to the first drive component (1) and to the second drive component (2).
8. The small electric appliance as claimed in any one of the preceding claims, characterized in that the first drive component (1) and the second drive component (2) are mechanically coupled to each other by at least one coupling element (10).
9. The small electric appliance as claimed in claim 7, characterized in that the coupling element (10) is rotatably linked to the first drive component (1) and to the second drive component (2).
10. The small electric appliance as claimed in any one of the claims 7 or 8, characterized in that the coupling element (10) is linked to at least one of the drive components (1, 2) with play across the direction of movement of the drive components (1, 2).
11. The small electric appliance as claimed in any one of the claims 7 to 9, characterized in that the coupling element (10) is rotatably mounted.
12. The small electric appliance as claimed in claim 10, characterized in that the coupling element (10) is rotatably mounted on a mounting axle (15) for fastening the drive mechanism to the small electric appliance.
13. The small electric appliance as claimed in any one of the claims 10 or 11, characterized in that the coupling element (10) is rotatably mounted eccentrically between the linkage points of the coupling element (10) on the first drive component (1) and on the second drive component (2).

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