EP0521295B1 - Shaver head, especially the razor blade unit of a wet razor - Google Patents

Abstract

The invention relates to a shaver head arranged at the front end of a handle, especially the razor blade unit of a wet razor, in which a single or double razor blade (5) is resiliently arranged in a plastic casing (1). In order to produce a shaver head, especially a razor blade unit of a wet razor, with improved spring bearing of the single or double razor blades, it is proposed according to the invention to attach the single or double razor blade (5) to a blade block (4) and to mount the blade block (4) on a four-bar mechanism (6) with two pivoting levers (7, 7') which can each be pivoted against the resistance of the spring between the plastic casing (1) and the blade block (4) on joints (A,C; B,D) with axes parallel to the cutting edge(s) (10) of the razor blade(s) (5). <IMAGE>

Description

The invention relates to a razor head arranged at the front end of a handle, in particular a razor blade unit of a wet razor, in which a single or double razor blade is resiliently arranged in a plastic housing.

With disposable wet shavers, a single or double razor blade is embedded in the shaver head in a plastic housing. If the razor head is designed separately and can be attached to a handle, for which purpose the handle and the razor head have mutually corresponding locking devices, this is referred to as a so-called razor blade unit.

In a razor blade unit of a wet shaving apparatus known, for example, from US Pat. No. 4,621,424, a plastic housing with a front guide strip is provided. Within this plastic housing two razor blades are each resiliently arranged to form a double razor blade. For this purpose, the two razor blades each rest on lateral spring tongues so that they can adapt to the contour of the face during the shave.

A disadvantage of this known system is that the angle and thus the position of the razor blades does not remain constant during the shave. Undesired vibrations or movements can occur in the respective razor blade, which can be the cause of unsatisfactory cutting performance.

Proceeding from this, the object of the invention is to create a razor head, in particular a razor blade unit of a wet razor, with an improved spring mounting of the single or double razor blades.

As a technical solution , the invention proposes that in a razor head according to the preamble of claim 1, the single or double razor blade is attached to a blade block and that the blade block on a four-bar mechanism with two each between the plastic housing and the blade block at joints with the (The) cutting edge (s) of the razor blade (s) parallel axes is pivoted against the spring force pivotable levers.

A razor head designed according to this technical teaching, in particular a razor blade unit of a wet razor with the single or double razor blade attached to a blade block, has the advantage of an improved spring suspension. Thus, when using the usual double razor blades, the two individual razor blades attached in parallel to one another can be moved in parallel and thus synchronously. A controlled directional movement of the razor blade block is achieved by means of the four-bar mechanism, this blade block executing a combination of rotational and translational movement. The appropriate movement of the blade block and thus the razor blades depends on a corresponding positioning of the joints. By this controlled directional blade bearing can achieve a movement in which undesirable vibrations or movements do not occur in the razor blade or in the razor blades, so that optimum cutting performance can be achieved. The resilient arrangement of the blade block within the plastic housing is such that the blade block is moved together with the razor blades essentially in the direction of the back during shaving. As soon as no more pressure is exerted on the razor block, the spring moves the blade block back into the basic position. Another advantage of the razor head according to the invention is that only slight frictional forces occur in the pivot points of the joints and that the razor head is insensitive to dirt.

In a preferred development, it is proposed that the one pivot lever in the front area of the blade block and the other pivot lever in the rear area of the blade block is hinged to the latter. This results in optimal possibilities for both rotary and translational movement of the blade block. The rear linkage of the pivot lever is also to be understood as the possibility that the rear side of the blade block has an indentation within which the pivot lever is, as it were, articulated within the blade block.

In a first alternative development of this it is proposed that the pivot lever pivoted in the front region of the blade block is pivoted with its other end in the front or middle, lower region of the plastic housing and the pivot lever arranged in the rear region of the blade block with its other end also in the lower region of the Plastic housing, but articulated behind it is. In a further development of this, the four joints preferably essentially form the corner points of a parallelogram.

In a second alternative variant it is proposed that the swivel lever articulated in the front area of the blade block is articulated with its other end in the front or middle, lower area of the plastic housing and the articulated arm articulated in the rear area of the blade block with its other end in the rear, upper area of the Plastic housing is articulated. If the plastic housing has the usual rear cover cap, it is proposed in a further development that the pivoted lever articulated in the rear, upper region of the plastic housing is articulated essentially below the cover cap.

These two variants are only two possible embodiments of the mounting of the blade block within the plastic housing, which enable a combination of rotary and translatory movement. However, the principle of the four-bar transmission is not limited to these two embodiments, but further embodiments are also conceivable. These depend on the corresponding choice of joint positions. Appropriate positioning of the joints within the plastic housing enables the desired movement guidance of the blade block and thus of the razor blades to be achieved.

In a preferred development of the swivel levers, they each have a bent-over tab at the end, through which parallel, round bearing rods are guided to the cutting edge (s) of the razor blade (s), which are fixed to the housing or fixed to the blade block. This represents a technically simple way to realize the joints.

In order to create a stable movement of the blade block overall, the width of the pivot levers extends essentially over the entire length of the plastic housing, so that the blade block is supported over its entire width.

A further development suggests that a spring is arranged on at least one pivot lever, which is supported on another part of the shaver head. This other part of the shaver head can be the plastic housing, the blade block or the other pivot lever. It is only required that the spring be supported in such a way that it brings about a restoring force of the blade block in the event of a deflection.

The spring is preferably integrally formed on the pivot lever. This represents a technically simple possibility of realizing the spring, in particular no additional part being required.

Alternatively, a compression spring can be arranged between the blade block or one of the pivot levers and the rear wall of the plastic housing. This compression spring, supported between these two parts, represents a technically simple possibility for pivoting the blade block back into the starting position.

This compression spring is preferably a curved leaf or wire spring.

Finally, it is proposed in a further development that the plastic housing and / or the blade block and / or the pivot levers define stops limiting the pivoting movement with respect to one another. This specifies the start and end positions of the blade block as it moves within the plastic housing.

Fig. 1

eine perspektivische Ansicht der Rasierklingeneinheit;

Fig. 2

eine Art Explosionsdarstellung der Rasierklingeneinheit in Fig. 1 vor dem Zusammenbau;

Fig. 3

eine Darstellung entsprechend der in Fig. 1, wobei jedoch der Klingenblock aus seiner Grundstellung ausgelenkt worden ist;

Fig. 4

einen Schnitt durch die Rasierklingeneinheit in der Grundposition des Klingenblocks;

Fig. 5

eine Darstellung entsprechend der in Fig. 4, jedoch nach dem Verschwenken des Klingenblocks;

Fig. 6

eine alternative Ausführungsform der Lagerung des Klingenblocks innerhalb des Kunststoffge häuses in einer Schnittdarstellung entsprechend der in Fig. 4;

Fig. 7

eine Darstellung entsprechend der in Fig. 6, jedoch nach dem Verschwenken des Klingenblocks.

Two embodiments of a razor head according to the invention in the form of a razor blade unit of a wet shaver are described below with reference to the drawings. In these shows:

Fig. 1

a perspective view of the razor blade unit;

Fig. 2

a kind of exploded view of the razor blade unit in Figure 1 before assembly.

Fig. 3

a representation corresponding to that in Figure 1, but with the blade block has been deflected from its basic position.

Fig. 4

a section through the razor blade unit in the basic position of the blade block;

Fig. 5

a representation corresponding to that in Figure 4, but after pivoting the blade block.

Fig. 6

an alternative embodiment of the storage of the blade block within the Kunststoffge housing in a sectional view corresponding to that in Fig. 4;

Fig. 7

a representation corresponding to that in Fig. 6, but after pivoting the blade block.

1 to 5 show a first embodiment and in FIGS. 6 and 7 a second embodiment of a razor blade unit.

The first embodiment of the razor blade unit shown in FIGS. 1 to 5 consists of a plastic housing 1. This is composed of a lower part 2 and an upper part 3, which can be placed and connected accordingly, for example welded, glued, latched, plugged together, etc.

A blade block 4 is resiliently mounted between the lower part 2 and the upper part 3 within the plastic housing 1, this blade block 4 being able to carry out a combination of rotational and translational movement by means of a corresponding bearing. On the blade block 4 two razor blades 5 are attached to form a double razor blade, for example glued or welded on.

The already mentioned storage of the blade block 4 within the plastic housing 1 for a combined rotary and translatory movement is realized by a so-called four-link mechanism 6. This four-link mechanism 6 consists of two pivot levers 7, 7 'which (as can be seen in FIG. 2) extend over the entire width of the plastic housing 1, ie from the left side to the right side. These pivot levers 7, 7 'are formed, for example, by a correspondingly bent sheet metal stamped part or by a plastic molded part and each have flanged ends at their ends 8 with a round inner recess. These tabs 8 are pivotally mounted on bearing rods 9 and thereby form joints A to D. The bearing rods 9 run parallel to the cutting edges 10 of the razor blades 5 and are either fixed to the housing (joints A and B) or fixed to the blade block (joints C and D).

As can be seen in FIGS. 4 and 5 of the first embodiment, the joints C and D of the blade block 4 are arranged on the front side and on the rear side thereof, while the joints A and B of the plastic housing 1 are inclined at the front downward in the plastic housing 1 are positioned so that the four joints A to D essentially form the corner points of a parallelogram.

Furthermore, it can be seen that a spring 11 is integrally formed on a pivot lever 7 and is supported on the front of the other pivot lever 7 'and thus tries to turn the pivot lever 7 counterclockwise into the basic position.

This basic position of the blade block 4 is shown in FIG. During shaving, pressure is exerted on the blade block 4, which has the effect that the blade block 4 is displaced in the direction of the rear wall 12 of the plastic housing 1 in a combined rotary and translatory movement (indicated by the arrow P). As soon as the pressurization ceases, the blade block 4 returns to the basic position shown in FIG. 4 due to the force of the force of the spring 11 from the pivoting position shown in FIG. 5. The basic position is defined by stops between the plastic housing 1 and the pivot lever 7, as is the maximum pivoting position by stops between the pivot lever 7 'and the rear wall 12 of the plastic housing 1.

In the alternative embodiment in FIGS. 6 and 7, the joints A to D of the four-bar transmission 6 are arranged somewhat differently. While the joints A and C of the front pivot lever 7 correspond in their positions substantially to those of the first embodiment, the joints B and C of the rear pivot lever 7 'are arranged somewhat differently. Thus, the joint D is arranged somewhat within the blade block 4 on the rear side thereof. Above all, the joint B is not in the lower region of the plastic housing 1, but in the upper region above the joint D below a cover cap 13 of the plastic housing 1. For this purpose, the rear pivot lever 7 'is also angled.

Another difference is that between the rear wall 12 of the plastic housing 1 and the blade block 4, a compression spring 14 is supported in the form of a leaf spring, which is received in a recess 15 of the plastic housing 1.

However, the mode of operation of this second embodiment is similar to that of the first embodiment, namely that the blade block 4 with its two razor blades 5 executes a combined rotational and translational movement, provided that a force is exerted on the blade block 4 starting from the basic position shown in FIG. 6. so that the blade block 4 reaches the end position shown in Fig. 7, which is limited by a stop between the rear pivot lever 7 'and the rear wall 12 of the plastic housing 1.

In the drawings, only two possible embodiments of the mounting of the blade block by means of a four-bar linkage 6 are shown. Other embodiments are basically conceivable. The main advantage of the storage of the blade block 4 by means of a four-bar mechanism 6 within the plastic housing 1 lies in a controlled directional movement of the blade block 4 during shaving, so that a movement of the razor blades 5 on the blade block 4 can be achieved, which is a combination of rotary and represents translational movement. Further advantages of the system are the low frictional forces in the joints A to D and the insensitivity to dirt, since the swivel levers 7,7 'can only be arranged sideways.

Reference list

1

Plastic housing

2nd

Lower part

3rd

Top

4th

Blade block

5

razor blade

6

Four-bar gearbox

7

Swivel lever

7 '

Swivel lever

8th

Tab

9

Bearing rod

10th

Cutting edge

11

feather

12th

Back wall

13

Cover cap

14

Compression spring

15

Recess

A

joint

B

joint

C.

joint

D

joint

P

arrow

Claims (13)

1. A razor head, especially a razor blade unit of a wet razor, with said razor head being disposed at the end of a handle and comprising:
   a plastic housing (1); with which a single or double razor blade (5) are displacebly arranged,
   characterised in that,
   the single or double razor blade (5) are fixed to a blade block (4) and that
   the blade block (4) is displaceably and yieldingly mounted in said plastic housing (1) against the spring force of two pivotable swivel levers (7, 7') to a four-pivot articulation arrangement (6) to pivot points (A, C; B, D) with two axes arranged between the blade block (4) and the plastic housing (1) and that extend parallel to said cutting edge means (10) of said razor blade means(5).
2. A razor had according to claim 1, characterised in that one of said swivel levers (7) is linked to a forward portion of said blade block (4) and the other of said swivel levers (7)' is linked to a rearward portion of said blade block (4).
3. A razor head according to claim 2, characterised in that said one of said swivel levers (7) that is linked to a forward portion of said blade block (4) has an opposite end that is linked to a forward or central, lower portion of said plastic housing (1), and wherein said other of said swivel levers (7) that is linked to a rearward portion of said blade block (4) has an opposite end that is also linked to a lower portion of said plastic housing (1) but rearward of where said one of said swivel levers (7') is linked thereto.
4. A razor head according to claim 3, characterised in that the four pivot point means ( A to D) essentially form the corners of a parallelogram.
5. A razor head according to claim 2, characterised in that one of said swivel levers (7) that is linked to a forward position of said blade block (4) has an opposite end that is linked to a forward or central, lower portion of said plastic housing (1), and wherein said other of said swivel levers (7') that is linked to a rearward portion of said blade block (4) has an opposite end that is linked to a rear, upper portion of said plastic housing (1).
6. A razor head according to claim 5, wherein said plastic housing (1) has a rear cover means (13), characterised in that said other of said swivel levers (7') that is linked to a rear, upper portion of said plastic housing (1) is linked essentially below said cover means (13).
7. A razor head according to any one of claims 1 to 6, characterised in that said swivel levers (7, 7') have ends which are provided with a bent-over tab (8) through which round mounting rods (9) are guided that extend parallel to said cutting edge means (10) of said razor blade means (5), with each of said mounting rods (9) being secured to one of said plastic housing and said blade block.
8. A razor head according to any one of claims 1 to 7, characterised in that said swivel levers (7, 7') have such a width that they essentially extend over the entire length of said plastic housing (1).
9. A razor head according to any one of claims 1 to 8, characterised in that said spring means (11) is disposed on at least one of said swivel levers (7) and is supported against another part of said razor head.
10. A razor head according to claim 9, characterised in that said spring means (11) is integrally formed on said at least one swivel lever (7).
11. A razor head according to any one of claims 1 to 8, characterised in that a compression spring (14) is arranged between the rear wall (12) of said plastic housing (1) and said blade block (4) or one of the swivel levers (7).
12. A razor head according to claim 11, characterised in that said compression spring (14) is a curved leaf- type spring or wore spring.
13. A razor head according to any one of claims 1 to 12, characterised in that at least one of said plastic housing (1), said blade block (4), and said swivel levers (7) define, relative to one another, stop means that delimit a pivoting movement of said swivel levers.

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