EP2004364B1 - Electric shaver with pivotable shearing head - Google Patents

Abstract

A dry shaver with a housing features a drive motor and a shaving head connected to the housing for pivotal movement about a pivot axis. The shaving head mounts at least two shaving systems, each comprised of an outer cutter and associated under cutters. The under cutters are adapted to be driven in an oscillatory linear motion relative to the outer cutter. The at least two under cutters are mounted respectively on separate oscillatory elements in the shaving head. The oscillatory elements are each connected to the drive motor via drive elements and are driven in mutually opposite directions.

Description

The invention relates to a dry shaver according to the preamble of patent claim 1.

Such a razor is from the US 2003/0221319 A1 known. This has oscillating elements with coupling portions which are straight, so that during a pivoting of the shaving head relative to the housing an undesirable elevational displacement of the coupling sections takes place relative to the drive elements.

From the WO 01/51260 A1 a razor is known, the shaving head is pivotally mounted about two axes relative to the housing.

Another dry shaver is from the DE 36 10 736 C2 known. The dry shaving apparatus disclosed there, although already characterized by very good adaptability to the shaving contour of the skin and thus provides superior shaving results. The known razor has a projecting from the housing oscillating driven drive pin which drives a drive plate which is arranged on the pivotable shaving head, wherein on the drive plate two lower blades are arranged, then soft together and in the same direction back and forth with the drive motor. Without suitable countermeasures, the same oscillating bottom blades would create disturbing vibrations for the user. Corresponding vibration reduction measures, for example by counterbalancing weights, are complex and require additional space in the pivotable shaving head, wherein the weight of the shaving head is additionally increased. Such additional measures are therefore unfavorable in terms of the compactness of the shaving head, complicate the balance and the dynamics in the adaptation to the respective skin contour and thus reduce the shaving performance and comfort.

The object of the present invention is to improve the known dry shaver; In particular, care should be taken with the least possible effort to ensure that no disturbing vibrations occur during operation. This should nevertheless allow a compact design of the dry shaver; In particular, the shaving head should be feasible in low height.

This object is solved by the characterizing features of claim 1.

By the solution according to the invention, the vibration behavior of a dry shaver with a pivotable shaving head can be extremely improved in a surprisingly simple manner or it can already compensate for vibrations directly in the shaving head itself. An embodiment of the invention provides that at least two translationally driven oscillating drive elements are present, which are each coupled to one of a plurality of vibrating elements. As a result, the space required for the arrangement of swing bridges in the shaving head itself can be extremely minimized. The oscillating elements are provided with coupling sections. These coupling sections are according to the invention concentric to the pivot axis. As a result, the coupling sections are moved during the pivoting about the axis exclusively on a respective associated radius. The axial distances of the eccentric sections from each other can therefore be chosen very small. Likewise, the coupling sections can be designed to lie close to each other. The eccentric portions must therefore have only a small axial extent, since, in contrast to straight-line design of the coupling sections no tilting of the coupling elements relative to the drive shaft in dependence on the pivot angle occurs about the axis.

An embodiment of the invention, in which only a rotationally driven drive element must be led out of the housing, provides that the drive motor has a rotationally driven drive shaft, which has at least two in the axial direction one behind the other arranged eccentric portions. Furthermore, it is conducive to a simple construction, when the drive elements engage directly in sections of the oscillating elements. Depending on the requirements or restrictions with regard to the available installation space, it can be advantageous if the drive elements are each connected to the oscillation elements by means of intermediate transmission means. This transfer means can be designed, for example, as a connecting rod or else as a joint push rod. The transmission of the drive energy into the shaving head is structurally particularly simple if each of the oscillating elements has a section provided with a slot for direct or indirect coupling of the respective drive element, the slot extending transversely to the pivot axis of the shaving head. Advantageously, at least one of the slots is formed as a passage slot, so that according to a particularly simple embodiment of the invention, the drive elements can be designed as two consecutively arranged eccentric. An optimized with respect to the required components and the associated assembly costs embodiment of the invention provides that two oscillating elements are mounted one inside the other, so that no additional storage means must be used.

Particularly large constructive and design freedom with respect to the entire geometry and design of the shaving head - for example, a shaving head with two different sized shear systems is conceivable - provides an embodiment of the invention in which the oscillating elements are driven with different sized amplitudes. If, for example, the lower blades of the respective shearing systems have masses of different sizes, unwanted vibrations result from this. By correspondingly tuned vibration amplitudes of different sizes, these can be compensated.

Other objects, features, advantages and applications of the present invention will become apparent from the following description of the embodiments. All described or illustrated features alone or in any combination form the subject matter of the present invention, also regardless of their summary in the claims or their dependency.

Fig. 1

in räumlicher Darstellung den prinzipiellen Aufbau eines Trockenrasierers gemäß der Erfindung,

Fig. 2

einen Schnitt parallel zur Hochachse und quer zur Schwenkachse durch einen erfindungsgemäßen Trockenrasierer,

Fig. 3

eine erfindungsgemäße Schwingbrückenanordnung in perspektivischer Dar- stellung,

Fig. 4

eine weitere Ausführungsform gemäß der Erfindung,

Fig. 5 bis 8

in mehreren Darstellungen einen alternative Ausführungsform die nicht unter den Schutzbereich der Ansprüche fällt, und

Fig. 9 und 10

eine weitere Ausführungsform der Erfindung.

It shows:

Fig. 1

in a spatial representation of the basic structure of a dry shaver according to the invention,

Fig. 2

a section parallel to the vertical axis and transversely to the pivot axis by a dry shaver according to the invention,

Fig. 3

an inventive swing bridge arrangement in perspective view,

Fig. 4

another embodiment according to the invention,

Fig. 5 to 8

in several illustrations an alternative embodiment not falling within the scope of the claims, and

FIGS. 9 and 10

a further embodiment of the invention.

Corresponding structural and functional parts are assigned the same reference numerals in the following.

Fig. 1 shows a dry shaver with a housing 1, which has in the region of the upper end face a recess 2 through which a first and a second eccentric portion 3 and 4 of a drive shaft protrudes. This drive shaft is driven in rotation by a not visible in this illustration electric motor.

At the front wide side of the housing, a trimmer 5 is arranged, which is displaceable and switchable via a switch 6. The upper end face also has two arms 7 and 8 designed as an extension of the narrow housing sides, which have bearing points 9 for receiving the shaving head 10. For this purpose, the shaving head 10 has corresponding bearings 11, which are arranged on the side cheeks. In the assembled state of the shaving head 10 is then mounted in the housing 1 such that it is pivotable about the axis X-X.

This pivoting ensures that the two shear systems of the shaving head 10 to be described later always rest optimally on the skin to be shaved, regardless of the angular position of the housing 1 relative to the skin.

In the shaving head 10, a first and a second lower blade 12 and 13 by means of associated swing bridges, namely the first swing bridge 14 and the second swing bridge 15, translationally parallel to the pivot axis X-X slidably mounted. Each lower blade 12, 13 has a plurality of successively lined up and parallel aligned blades.

If the shaving head 10 is mounted on the housing 1 via the bearing points 9, then the two eccentric sections 3 and 4 respectively engage in corresponding coupling sections of the associated vibration bridges 14 and 15. When the drive shaft is rotating, the two lower blades 12, 13 are then moved in an oscillatory manner in opposite directions relative to one another. Each lower blade 12, 13 is associated with a shaving foil 16, which is provided in a removable frame 17. The latter has on its inside corresponding recesses, by means of which the removable frame 17 can be coupled in conjunction with arranged on the shaving head 10 locking bars 18 fixed to the shaving head 10.

The shear sheets 16 are curved, include the rounded blades of the lower blades 12, 13 partially and have a plurality of holes for the entry of the hair to be shaved. In conjunction with the oscillating reciprocating motion of the lower blades 12, 13, the hairs passing through the holes are then sheared between the shear foil and the corresponding blade of the lower blade.

Fig. 2 shows a central section perpendicular to the axis XX through a dry shaver according to the invention. In this illustration, one recognizes the arranged in the housing 1 electric motor and its drive shaft 20, which is driven to rotate. The electric motor 19 is firmly integrated in the housing 1 and can be actuated by an on / off switch, not shown. On the drive shaft 20 is secured against rotation and axially secured against displacement, a molded part, which has a first and a second eccentric portion 3 and 4 respectively. In this case, these eccentric portions are arranged axially one behind the other and their eccentricities are diametrically opposite, so are rotated by 180 ° from each other. The first eccentric portion 3 is closer to the electric motor 19, while the second eccentric portion facing the shaving head 10. The first eccentric portion 3 engages in the coupling portion 21, which is integrally formed on the first swing bridge 14 and thus connects the first lower blade 12 with the electric motor 19. At the second swing bridge 15, a coupling portion 22 is also formed, which is in communication with the second eccentric portion 4 and thus with the electric motor 19.

The eccentricities of the two eccentric portions 3 and 4 are about 1.5 mm, so that when operating the electric motor 19, the lower blade 12, 13 perform a mutually opposite vibration with the amplitude of about 3 mm. Since the eccentric portions are arranged on the same drive shaft 20, the vibrations of the lower blades 12, 13 also have the same vibration frequency. As long as the moving masses are the same size, vibrations are completely compensated by the opposing motion. Of course, it is also possible to build a shaving head, which has shear systems of different sizes, which then leads to different sized moving masses. In order to achieve a complete compensation of the vibration forces in this case, it is possible to tune the drive system so that the eccentricities of the eccentric portions differ from each other. This would impose a lower amplitude on the larger mass shear system than the lighter shear system.

The coupling portion 21 has to receive the eccentric portion 3 a transverse to the pivot axis XX slot 23, while the coupling portion 22 has an equally extending slot 24 in which the second eccentric portion 4 is received. The length of the slots 23 and 24 is matched to the maximum pivot angle of the shaving head 10. In the vertical direction, the slots 23 and 24 are made continuous; at least the slot 23 must be continuous, so that the second eccentric portion 3 can be passed through it. The slot 24 may also be formed as a non-continuous slot-shaped groove. Both swing bridges 14, 15 each carry a receiving pot 25 and 26, respectively, in which the lower blades 12 and 13 can be mounted in a conventional manner by means of corresponding axes or pins. Between the receiving pots 25, 26 and their associated lower blades 12 and 13 are each spring elements arranged biasing the lower blade in the direction of the shear sheets 16. In this way, a flat concern of the lower blade on the associated shaving foil is always ensured.

The Fig. 3 shows a swing bridge assembly according to Fig. 2 In this figure, it can be clearly seen how the two coupling sections 21 and 22 are interleaved and each cover at least perpendicular to the direction of oscillation (double arrow) the area below both swing bridges.

In the region of the attachment points 27, by means of which the swinging bridges are fixed in the shaving head 10, the same are gezinken into each other, so that they can be fixed in the shaving head 10 due to this positive connection in each case by means of a single common fixing screw. From this attachment zone lead a total of four leaf-shaped sections 28, 29 vertically downwards, the sections 28 of the first swing bridge 14 are left and right next to the carrier 30 of this swing bridge, and connect this elastic with the attachment zone. The same applies to the second swing bridge 15 and its leaf-shaped sections 29, which are assigned to the carrier 31. Thus, the coupling portion 22 can move swinging in its installation space, a sufficient clearance is provided between this and all parts of the first swing bridge 14.

Fig. 4 shows an embodiment of the invention in which the coupling portions 21, 22 of the swing bridges 14, 15 are not interleaved, but are arranged side by side. Also in this example, an electric motor 19 is arranged with a drive shaft 20 in the housing 1 of the shaver, wherein on the drive shaft 20, two eccentric portions 3 and 4 are arranged. On each of the eccentric portions 3, 4, a connecting rod 32 and 33 is mounted, the pins 34 and 35 with associated coupling portions 21 and 22 of the swing bridges 14 and 15 is in communication. The pins 34 and 35 are slidably mounted in groove-shaped slots 23 and 24, wherein, as in the preceding figures, these slots 23 and 24 in the associated coupling portions 21 and 22 extend transversely to the pivot axis XX of the shaving head 10. The oscillating bridges 14 and 15 lie one behind the other in the drawing plane and each carry one of the lower blades 12 and 13. When the drive shaft 12 rotates, the oscillating linear oscillation is transmitted to the swing bridges parallel to the pivot axis XX via the connecting rods 32, 33. Since - as in the previous example - the eccentric sections 3, 4 by 180 ° against each other are twisted, the swinging movement, the swing bridges 14, 15 in opposite directions to each other. Due to the course of the slots 23, 24 transversely to the pivot axis XX and the displaceable receiving the pins 34, 35 in them, the shaving head 10 can be pivoted while maintaining the driving connection between the electric motor 19 and swing bridges 14, 15.

FIGS. 5 to 8 show an embodiment which does not fall under the scope of the claims, in which two opposite to each other oscillating moving drive elements protrude from the housing 1. These drive elements are two pin-shaped oscillators 36 which are guided out of the housing in a sealed manner and have recesses for the articulated reception of the lower end 38, each of which has a joint push rod 37. The storage of the joint push rods in the oscillators is both pivotable, as well as linearly displaceable.

In the FIGS. 5 and 6 the housing of the dry shaver and the shaving head 10 is shown separated from each other, it was dispensed with the representation of a retaining fork for pivotally receiving the shaving head 10. This fork is led out of the housing 1 through the openings 39 and contains bearings which cooperate with corresponding bearing points of the shaving head in a conventional manner.

Fig. 7 shows a side view in which the shaving head 10 is in a central position, while the Fig. 8 the deflected pivot position of the shaving head 10 relative to the housing 1 represents.

The upper end 40 of each of the two articulated push rods 37 is articulated via corresponding eyelets 41, each with a swing plate 42. This connection allows a pivotability of the joint push rod 37 about an axis parallel to the pivot axis XX extending axis. It also lies parallel to the direction of oscillation of the oscillators or the respectively associated with them vibrating plates 42. Due to this connection, the vibrating plates 42 are driven in opposite directions linearly oscillating. These contain not shown arrangements for receiving the lower blade. The pivotability of the articulated push rods within their bearings and the linear displaceability of the lower end 38 within the oscillators 36 is coordinated so that this drive connection can follow the maximum pivoting of the shaving head 10 relative to the housing 1 about the pivot axis XX.

Another embodiment of the invention show the FIGS. 9 and 10 which, like the representation in the FIGS. 5 and 6 on the one hand show a housing 1 with this separated shaving head 10. Also in this embodiment, two adjacently located oscillators 36, which are linearly driven in opposite directions to each other in an oscillating manner, protrude out of the housing 1. The oscillators 36 have plate-shaped sections 43, which carry pin elements 44 at an inwardly bent region. These pin members 44 are arranged so far inward that they move in oscillating operation of the oscillators 36 on a common line. As in the previous embodiment, the shaving head 10 is connected via an unillustrated fork member about the axis XX pivotally connected to the housing 1. In the assembled state of the shaving head 10, the pin elements 44 each engage in an associated transverse groove 45, which is respectively formed on a swing plate 42, and extends transversely to the pivot axis XX. The two oscillating plates 42 are mounted parallel to the pivot axis XX displaceable in the shaving head 10 and are parallel to each other. Each transverse groove 45 extends arcuately about the pivot axis XX. In addition, each transverse groove 45 is disposed in a portion of the associated rocking plate 42 which also at least partially overlaps the adjacent rocking plate. These sections are nested in a staircase shape. The two swing plates can be supported by appropriate arrangements, such as tongue and groove or dovetail connection slidably. The double arrows in the FIGS. 9 and 10 in each case indicate the direction of oscillation of the oscillatory movement of the affected components, wherein the two oscillators 36 and thus also the respective lower blade-carrying vibrating plates 42 are driven in opposite directions to each other.

Claims (10)

1. A dry shaver having a housing (1) accommodating a drive motor (19), further having a shaving head (10) connected to the housing (1) so as to be pivotable about a pivot axis (X-X), the shaving head supporting at least two cutter assemblies, each comprising an outer cutter (16) and associated undercutter (12, 13), the undercutters (12, 13) being drivable linearly oscillating relative to the outer cutter (16) and the at least two undercutters (12, 13) each being mounted on separate oscillation elements (14, 15; 42) in the shaving head (10), each of which are in communication with the drive motor (19) via drive elements (3, 4; 37; 44) and driven in mutually opposite directions, characterized in that the oscillation elements have coupling sections (21, 22) that are formed concentrically with respect to the pivot axis (X-X).
2. The dry shaver according to Claim 1, characterized in that at least two drive elements (36) are provided that are driven translationally oscillating, each being capable of being coupled to an oscillation element (42).
3. The dry shaver according to either of the preceding Claims, characterized in that the drive motor (19) has a rotationally driven drive shaft (20) that has at least two eccentric sections (3, 4) arranged one behind the other axially.
4. The dry shaver according to any of the preceding Claims, characterized in that the drive elements (3, 4; 36) directly engage in sections (23, 24; 45) of the oscillation elements (14, 15; 42).
5. The dry shaver according to any of the preceding Claims, characterized in that each of the drive elements (3, 4) is connected to the oscillation element by means of interposed transmission means (32, 33).
6. The dry shaver according to Claim 5, characterized in that each of the transmission means has at least one connecting rod (32, 33).
7. The dry shaver according to any of the preceding Claims, characterized in that each of the oscillation elements (14, 15; 42) has a section provided with a slot (23, 24; 45) for direct or indirect coupling-in of the drive elements, the slot extending transversely to the pivot axis (X-X) of the shaving head (10).
8. The dry shaver according to Claim 7, characterized in that at least one of the slots (23) is formed as a through slot.
9. The dry shaver according to any of the preceding Claims, characterized in that at least two oscillation elements (14, 15; 42) are mounted one inside the other.
10. The dry shaver according to any of the preceding Claims, characterized in that the oscillation elements (14, 15; 42) are driven at differently sized amplitudes.

Images