DE1194289B - Dry shaver - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

B26b

German class: 69-12 / 02

Number:
File number:
Registration date:
Display day:

1194289
T24799IC / 69
September 28, 1963
June 3, 1965

The invention relates to a dry shaving apparatus with a cover shear plate and one of these shear plates adapted cutting element that maintains contact with the shear plate is held in a rotationally free manner by a drive device parallel to the plate, wherein on the Cover shear plate has a large number of openings for receiving the hair and on Cutting element a plurality of cutting edges are provided.

In the training of dry razors, it is important to ensure that when quiet, vibration-free and low-noise operation results in the highest possible shear performance. Aimed for a design of the dry shaver as small as possible and a shape of the cover shear plate, in which at least one delimiting edge running in a straight line is present.

It is known that the shear performance depends, among other things, very much on the relative speed between the cutting element and the cover shear plate is dependent. In known dry shavers as the cutting element rotates, this relative speed between the cutting element and cover shear plate increases from the center of rotation in the radial direction. That means that the ideal relative speed only prevails where the cutting edges of the cutting element at a given Speed have the distance from the center of rotation at which the peripheral speed of this corresponds to the ideal relative speed. The zone of the ideal relative speed is therefore a very narrow circular ring that covers only a very small part of the total shear surface.

In another known embodiment of dry shavers, the cutting element is out and moved here. It follows that the relative speed between the cutting element and the cover shear plate rises and falls continuously from the value zero to a certain maximum value. the ideal relative speed between the cover plate and the cutting element is therefore only during present for a brief moment.

In dry shavers with a reciprocating cutting element, there is also the Disadvantage that a high motor power is required to constantly accelerate and decelerate the cutting element and its drive elements. The movement of the cutting element produces very strong noises and vibrations. Included it does not matter whether the back and forth movement is straight or circular.

Dry shaver

Applicant:

Ralph Landon Tweedale, Southfield, Mich.

(V. St. A.)

Representative:

Dipl.-Ing. F. Thieleke and Dr.-Ing. R. Döring,

Patent attorneys, Braunschweig, Jasperallee la

Named as inventor:

Ralph Landon Tweedale, Southfield, Mich.

(V. St. A.)

Finally, dry shavers are known in which the cutting element of at least three elongated helical springs, which are attached to a plate, held and against the cover shear plate is pressed. This cutting element is connected to a drive motor via a crank. This is intended to ensure that the cutting element is moved without rotation and a movement path describes, which is designed in the form of a self-contained trajectory, in which Describe the cutting element is always moved parallel to itself.

In this known dry shaver, however, there is the disadvantage that a rotation-free movement of the cutting element can only occur if there is load symmetry. It will However, the cutting element is more heavily burdened on one side by thicker whiskers that are standing more densely on one side, see above torsional vibrations are triggered, which superimpose the movement of the cutting element, so that rotate and vibrate again. In addition, this known dry razor are not prevented that the springs give way and that the cutting element lifts off the cover shear plate against the pressure of the spring and without any shearing action Hair moving past.

Another, not insignificant disadvantage of the known dry shaving apparatus also exists in that to the required constant deformation of the springs that the cutting element in contact hold with the cover shear plate and the it

509 578/46

anchor in such a way that it is moved parallel to itself, energy is required from the drive motor of the dry shaver must be applied and is lost for the shearing process. Of the The rule mentioned at the outset, to make dry shavers as small and handy as possible, stands this Fact, however, hinders, because it leads to the need to use more powerful motors, than would be necessary for the cutting process itself.

The invention is based on the object of addressing the disadvantages of the known dry shavers avoid and train a dry shaver of the type mentioned so that the cutting element to achieve a level that is the same at all points on the shear surface and remains constant over time Shear action is moved rotation-free and parallel to itself, without any drive energy is lost and without superimpositions can occur in the rotation-free movement.

To solve this problem, a dry shaving apparatus of the type mentioned is characterized according to the invention in that the drive device engages at least two on the cutting element Has cranks at a distance from each other, preferably on the longitudinal center line of the Cutting element are rotatably mounted.

The use of two cranks to guide the cutting element creates a positive guide achieved along a self-contained path in which the cutting element is always parallel to itself itself is moved, but never perform reciprocating movements or torsional vibrations can.

If two cranks are provided, it is useful to place them on the longitudinal center line of the cutting element to store, while with three or more cranks a storage is to be used in which the Crank together to form a triangle or square.

The leadership of the cutting element and the achievement of its rotation-free movement is at the According to the invention trained dry shaver the result of using the two or several cranks, so that the drive energy of the motor is not lost. With the self-contained The path movement of the cutting element continues to be constant over time and over the entire length Shear surface evenly distributed relative speed between cutting element and cover shear plate, so that the shear action is the same at all points on the shear surface. There going back and forth Movements are avoided, results in the dry shaving apparatus designed according to the invention in addition, it also runs smoothly and quietly.

In the case of cutting elements moving back and forth, the direction of the relative movement a main cutting direction is already essentially defined between the cutting element and the cover shear plate. The slots in the cover shear plate and also run in accordance with this cutting direction the cutting edges on the cutting element.

In order to have a substantially non-directional in the dry shaver according to the invention To achieve cutting effect, the invention further provides that the openings in the cover shear plate designed as elongated slots and extending in a plurality of different directions are arranged and that the cutting edges of the cutting element in a plurality of different Directions run.

In an expedient embodiment of the dry shaving apparatus according to the invention, it is provided that the elongated slots in a consisting of three groups of slots, themselves repeating patterns are arranged on the shear surface, each group of at least

ίο two parallel to each other, but inclined to the Slits of the other groups of the pattern are individual slits and that the Cutting element has cutting edges arranged like a pattern, which form equiangular triangles, the distance of the cutting edges and the stroke of the cranks so to the dimensions of The patterns formed by the slots are matched to each slot of a group at least once in the course of a self-contained path movement of the cutting element one parallel to the Cutting edge running slitting passes.

An embodiment of the dry shaving apparatus according to the invention is shown in the drawings.

F i g. 1 is a perspective view of a dry shaving apparatus according to the invention;

F i g. 2 shows a part in section along section line 2-2 in FIG. 1, in a larger one Scale;

F i g. 3 is a section taken along section line 3-3 in FIG. 2, and

F i g. Figure 4 is an even larger scale diagram showing a preferred pattern of the slots the shear plate and the webs on the cutting element illustrated.

The shaver has a base body 10, which has the drive means in the form of an electric motor (not shown) and has a socket 12 for receiving the connecting cable. At A head piece 14 is attached to the base body and is used to drive the motor. The head piece can according to the details in FIGS. 2 to 4 be formed.

The head piece 14 has a peripheral frame 16 which is T-shaped in cross section and is releasably fastened to the body 10 by fastening means not shown. On the frame 16 is suitably a perforated steel blade (shear plate) 18 attached, for example by at 20 indicated flanging. For this purpose, a beaded edge extending around the entire edge can be used be provided, which is made before the final assembly of the head piece. It however, only flanged areas can be provided in a few places that are less pronounced are so that the shear plate 18 is removed from the frame 16 by hand and put back on again can be. The shear plate 18 is spherical over its larger area, with on its circumference sharper shaped shoulders are provided. A cutting element 22 made of substantially thicker Metal that has slightly smaller dimensions in projected area than the shear plate 18, is located under the shear plate and has a spherical surface, with its edges corresponding the curvatures of the shoulders of the shear plate 18 are curved and adapt to these exactly.

The frame 16 has two transverse bridge elements 24 which extend downward, as shown in FIG. 3 shows, can be cranked. These bridge elements have central sections which are arranged along the longitudinal center line of the frame and form bearings 26 for two crank arms 28 balanced against one another. The crank arms 28 are provided with non-circular drive recesses and with eccentric bearings 32 for receiving drive pins 34 which are integrally attached to the lower surface of the cutting element 22. The pins 34 are preferably slightly barrel-shaped to accommodate the slight conical movement in which they participate. The crank arms 28 are equipped with counterweights 36 which are arranged to counterbalance the imbalance caused by the crank arms and the cutting element 22. The crank arms can be driven by two rotating shafts 38 which are mounted in bearings 40 and are driven synchronously in the same direction by the drive motor (not shown).

The pattern of the slots in the shear plate 18 and the cutting webs in the cutting element 22 can be designed in various ways. A preferred shape of the pattern is shown in FIG. 4 illustrates. In this pattern, the elongated slots 42 are arranged in three groups of three slots each and are distributed over a hexagonal area. These surfaces are repeated over the entire working surface of the spherical top of the cover shear plate 18. The cutting element 22 is designed in the form of a grid of webs 44 which are arranged in three directions at 60 ° so that triangular spaces remain between the webs. The spacing of the rods or webs 44 and the pitch caused by the crank arms 28 are selected in relation to the size of the hexagonal pattern of the slots 42 so that each group formed from three slots is through a cutting web 44 which runs parallel to the direction of the slot group , is swept over one or more times during each orbit cycle of the movement of the cutting element 22. So if the cutting element 22 in the direction of FIG. 4 indicated arrows is moved, the web 44 α has a shear position with the longitudinal edges of the slot 42 a, to which the web maintains a parallel position at all times. The web 44 b is in the same way in shear with the edges of the slot 42 δ and the web 44 with the slots 42. It can also be used other patterns of non-parallel slots 42 and corresponding web grids of the cutting element, which on squares, pentagons or build other regular or irregular figures as a basic pattern. The step size of the crank arms 28 should be equal to a single or multiple of the distance between parallel cutting webs, increased by a small addition.

The spherical outer shape of the cutting element and the shear plate gives the two elements much greater strength than one flat shape, on the grand of the arc effect. The cutting element, which has a substantial thickness, supports almost the entire underside of the shear plate with the help of a grid-shaped pattern of a small distance between adjacent bars. Although it is not in itself necessary to be in To provide slots in the shoulders 46 or 48 of the shear plate 18, such slots may be provided if desired the cutting element corresponding cutting ridges along the edges of the cutting element 22 has. Due to the fact that the slots 42 in the shear plate are elongated and Oriented in several directions, it ensures that long hair has a corresponding opportunity have to penetrate through the shear plate to be sheared. Because the cutting ridges a component of movement in the direction of the length of the slot in the shear plate during the Has shearing process, a combined rolling and shearing effect occurs on each hair that the shearing process can be particularly effective.

The contact between the cutting element 22 and the shear plate 18 is resiliently maintained, in order to take the wear and tear and minor changes into account. This yielding Support is preferably achieved in that the edge of the shear plate 18 in such Way is crimped or crimped that the bridge webs 24 are slightly bent. On the other hand, the drive shafts 38 can be resiliently loaded so that they the crank arms Pretension 28 upwards.

In a modified embodiment, the cutting webs 44 can be replaced by slots, the side walls of which present spaced-apart cutting edges.

It was found that with a razor as described above, a high effective shear rate is obtained with negligible skin stress. At the same time, the circular movement of the cutting element leads together with the non-parallel movement Alignment of the slots for an effective clipping of long hair on the ground a combined roll and shear effect. In addition, it was found that such a razor is equally effective regardless of the direction in which it is moved. aside from that a very improved shear effect is obtained on concave, convex and flat skin areas, which is also an excellent way to shave a straight edge.

Claims (3)

Patent claims: 1. Dry shaver with a cover shear plate and one of this shear plate adapted Cutting element that by maintaining contact with the shear plate a drive device is held in a rotationally free movement parallel to the plate, wherein on the Cover shear plate a large number of openings and serving to accommodate the hair a plurality of cutting edges are provided on the cutting element, characterized in that that the drive device has at least two cranks (28) which engage the cutting element (22) and which are spaced apart from one another are preferably rotatably mounted on the longitudinal center line of the cutting element (22). 2. Apparatus according to claim 1, characterized in that the openings in the cover shear plate (14) designed as elongated slots (42) and in a plurality of different Directions are arranged to run and that also the cutting edges (44) of the cutting element (22) in a plurality of different directions get lost. 3. Apparatus according to claim 2, characterized in that the elongated slots in one each consisting of three groups of slots, which are continuously repeated on the shear surface Patterns are arranged, each group consisting of at least two parallel to each other, however individual slits running inclined to the slits of the other groups of the pattern consists, and that the cutting element (22) has cutting edges (44) arranged in a pattern, IO which form equiangular triangles, the distance between the cutting edges and the stroke of the Cranks are matched to the dimensions of the pattern formed by the slots that at each slot of a group at least once in the course of a self-contained path movement of the cutting element passes a cutting edge running parallel to the slots. Considered publications:
German patent specifications No. 802 052, 810 970,
685, 1 007 664, 1 014 879, 1 066 912, 1077 568; U.S. Patent No. 2372401. 1 sheet of drawings 509 578/46 5.65 © Bundesdruckerei Berlin