MXPA99007592A - Safety razors - Google Patents

Abstract

A safety razor blade unit having a plurality of blades (4) presenting substantially parallel blade edges. The blades are disposed between a guard and a cap. The blades are independently movable and are carried by supports (5). At least one of the supports has spaced portions (12) projecting forwardly of the associated blade to present skin contacting portions.

Description

BLADE UNIT FOR SHAVING MACHINES DESCRIPTION OF THE INVENTION This invention relates to a blade unit for shaving machines and, in particular to a safety razor unit having at least one blade with a cutting edge that moves across the surface of the blade to be shaved. by means of a handle to which the blade unit is attached. The ho-unit may be mounted on the handle so as to allow the blade unit to be replaced by a new blade unit when necessary. Spare blade units are commonly referred to as cartridges. As an alternative, a blade unit can be permanently attached to the handle, with the intention that the entire razor be discarded when the razor is not nicked. The housings generally include protective and lid surfaces to contact the skin in front of and behind the leaves / s, respectively, playing an important role in the establishment of the so-called shaving geometry. , that is, the parameters that determine the orientation of the blade, and its position with respect to the skin during shaving.

REF-: 31002 Previous proposals have been made to equate a blade unit for shaving machines with a structure similar to comb, to be cut with the skin from the front of the edge of the ho, whose structure is arranged, in some cases , on the protective surface or part of the psma, while other arrangements include the comb structure in a space located between a pair of leaves arranged in tandem. Peir structures are designed to achieve, on the one hand, a balance between safety and comfort and, on the other hand, a shave close to the skin. Among the examples of comb structures of the prior art, we will mention that described in US Patents No. 3,004,337, 4,272,885 and 5,359,774, in which it is explained that improved safety and comfort originate in reduced contact between the skin and the cutting edge of the noja. Prior art units having comb structures are provided with fixed jaws and are not easily attachable to use blade units in which the blades are mounted to be movable due to the forces exerted during shaving, in order to vary the geometry of shaving. According to the present invention, a razor unit is provided for shaving machines comprising a frame with protective surfaces and cover therein, a plurality of sheets with substantially parallel cutting edges mounted on the frame, between the protective surfaces and cover, the sheets being held in respective sheet holders to move independently within the frame and to be able to vary the geometry of the shaving according to the forces applied on the sheets during shaving, having at least one of the sheet holders, elevents rigidly connected to the same, separated along the ho held in said blade holder and projecting towards the cutting edge of the blade, has the elements portions that come into contact with the skin to touch the skin located immediately in front of the blade. sheet and substantially tangential to the cutting edge of the sheet. The blade units having comb frames of the prior art sacrifice proximity to the skin to improve safety and comfort. It has been found that an excellent vicinity to the skin can be obtained with greater safety and comfort with a form or embodiment of a razor blade unit of the present invention. In the preferred embodiment, the projecting elements projecting forward have upper surface portions, which-viewed in lateral elevation-extend rectilinearly with respect to a point separated from the cutting edge of the sheet by a distance of the range of 0.10 to 0, 30 mm. The projecting elements are preferably integral with the sheet holder, although they may be formed in a member firmly attached to the sheet holder. In either case the elements can be easily and conveniently incorporated into a blade unit having movable blades and the elements remain effective despite the movements of the blades that occur during shaving. In addition, the elements have surfaces that touch the skin, which in all cases are closely adjacent to the cutting edge of the ho a. Thanks to the upper surface portions, which may be flat or arched, arranged substantially in a common plane with the cutting borae of the blade, the elements have a tendency to operate in a similar manner to skis or sled skates when they slide over the surface of the skin, thus guiding the sheet so that it makes an effective contact with the skin, while preventing any tendency of the sheet to move in a longitudinal direction with respect to the edge of the sheet.

In a preferred construction, the projecting elements have flat sides and the side edges of the upper surface portions gradually emerge towards radial or divergent flank surfaces extending to the flat sides. This feature contributes to the effectiveness of the elements, ensuring that comfort is maintained. Conveniently the width of the elements is in the range of 0.1 to 0.3 mm and the width of the upper surface portions in contact with the skin is not more than 0.1 mm, which avoids any tendency of the elements to flatten the hairs against the surface of the skin. The elements are preferably arranged with a light of less than 2 mm, for example in the range of 0.5 mm to 1.5 mm, a light of 1, Omm being especially suitable. To ensure a gradual initial contact between the elements and the surface of the skin, they can be provided with rounded nose portions at their anterior ends, gradually bringing these nose portions toward the upper surface portions.

These and other features of a preferred embodiment of the invention are described in detail below, with reference to the accompanying drawings, in which: Figure 1 is a partial perspective view of a blade unit for razors; Figure 2 is an enlarged perspective view showing part of a sheet and its support; Figure 3 is a final view of the sheet and its support; Figure 4 is a front view of a part of the sheet holder; Figure 5 is a perspective view, a modified leaf holder; Figure 6 is an enlarged perspective view of one of the elements of the sheet holder of Fig. 5; Figure 7 is a plan view of the element shown in Fig. or; Figure 8 is a front elevation view of the element shown in Fig. 6; Figure 9 is a side elevation view of the element shown in Fig. 6; Figure 10 is a perspective view of another blade and shaver support assembly; Figure 11 is an enlarged perspective view showing part of the assembly of Fig. 10; and Figure 12 is an exploded perspective view of the assembly shown in Figure 10. Figure 1 illustrates a blade unit for shaving machines or cartouche having a molded plastic frame 1 in which surfaces are provided of protection and cover and including, respectively, a strip 2 of elastomer material with longitudinal burrs and a strip 3 of lubricating material, both joined in a fixed manner to the frame. Mounted between the cover and the cover are three parallel sheets 4 with their cutting edges directed forward, arranged in series, between the cover and the cover. Each leaf 4 is fixedly connected to the leaf holder 5 and in a known manner, the ends of the leaf holders are connected to the frame to allow the movement of the leaves with respect to the frame, counteracting the action of the springs ique are not shown], by empire of the applied forces centers the leaves during shaving. As shown in more detail in Figures 2-4, each support from h to 5 includes an upright portion, in genre, of cross member 10, from whose upper edge extends a sheet platform 11 inclined forward and upward, against which surface upper is joined sheet 4, for example by spot welding. Evenly spaced along the sheet platform and projecting forward therefrom are comb elements 12 which are perpendicular to the edge of the sheet. The formation, shape, position and dimensions of the elements 12 in the sheet holder are the important novel aspects of this invention. As noted, the elements 12 have flat sides, at least in the sections protruding forward of the cutting edge of the sheet and flat upper surface portions 14 which are connected to the side faces by radial edges 15. The leading ends of the elements 12, located in front of the upper surface portions 14 have rounded noses 16 leading gradually to the surface portions 14. The lower portions 17 of the elements 12 have upper surfaces of steeper inclination than the sheet platform surface to remain close to the surface. edge, on the underside of the sheet 4, although this is not essential and a greater separation between the lower side of the ho and the elements is acceptable. The rear or rear ends of the upper surface portions 14 are closely adjacent to the edge of the sheet, the width of the separation therebetween being several times less than the distance A (Figure 3) that runs from the edge of the sheet. a to the front or the front ends of the surface portions 14. The surface portions 14 of all the elements of the hoof support are in a common plane which is generally tangential to the edge of the ho arranged in the bra, that is to say that it contains said edge. The distance A is in the range of 0.10 to 0.3 mm, more especially 0.15 to 0.2 pun. The width of the elements located between their flat side faces is in the range of 0.5 to 1.5 mm, for example approximately 1.0 mm and the elements are positioned at 1.0 mm intervals. In practice, the projecting elements 12 of the leaf holders have a guiding effect, the blade unit influencing to move on the skin in a direction perpendicular to the cutting edges of the leaves, the elements acting in a manner Similar to skis or sled skates, sliding on the surface of the skin. In this way it is possible to obtain greater security and comfort. At the same time, the elements 12 ensure an effective cooperation of the sheets with the surface of the skin, which produces excellent shaving results in terms of proximity to the skin. Figures 5 to 9 illustrate a modified blade holder that can be used with one or more blades in the razor nozzle unit of Figure 1. The modified blade holder is the same as described with reference to Figures 2 to 4, except that the shape of the forwardly projecting elements 22 is different. Instead of having flat upper surface portions, the elements have arcuate central upper surface portions 24, having a radius of curvature of about 0.07 mm, the lateral edges of which gradually emerge with diverging flank surfaces 25, which extend towards the flat side faces. As seen in the side plan view (Figure 9), the crests of the arcuate upper surface portions extend rectilinearly to a point 27, in which these surface portions emerge gradually with rounded noses 26. The dimensions of the elements 22, in terms of width and spacing, can be the same as those described for Figures 2 to 4 and when a sheet is mounted on the sheet holder, the distance of the point 27 from the edge of the sheet will be the same as the distance A mentioned above. Figures 10 to 12 illustrate a razor blade and a blade holder assembly which, instead of being integral with the blade holder as in the embodiments of Figures 1 to 9, projecting elements 32. forward of the edge of the sheet are formed in a separate injection molded plastic member 30 that is firmly attached to the sheet holder 31. As seen, the molded member 30 has integral projections 34, spaced along the same, which they are inserted through corresponding openings 35 in the sheet holder, the protruding ends of the projections being deformed for example by the application of heat and pressure, so that they enlarge radially towards the rear part of the sheet holder, holding the molded member to the sheet holder. The upper edge of the molded member has a shape that follows the outline of the sheet holder on the underside of the portion carrying the sheet 36 and the elements 32 project forwardly from this upper edge. The upper faces of the rear end of the member 30 define two abutting surfaces with the blade holder 31, to assist in obtaining an accurate alignment between the projecting elements and the sheet holder and therefore, with the cutting edge of the sheet 36. The projecting elements 32 may have the same shape and dimensions as the elements. elements 22 of the sheet holder described above with reference to Figures 5-9 and are preferably positioned relative to the cutting edge of the sheet 36 also in the same manner as in the previous embodiments. The sheet and the holding assembly of Figure 10-12 can be used with one or more of the sheets and sheet holding assemblies of the razor blade unit of Figure 1. Modifications and changes can be made within the spirit and scope of the present invention, limited only by the appended claims.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects or products to which it refers.

Claims (12)

n CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A blade unit for razors characterized in that it comprises a frame with protective and lid surfaces thereon, a plurality of sheets with substantially parallel cutting edges mounted on the frame, between the protective surface and the lid surface, being held the leaves in respective leaf holders to move independently within the frame, to vary the shaving geometry according to the forces exerted on the leaves during shaving, having at least one of the leaf holders elements separated at intervals along the blade held in said blade holder rigidly connected thereto and projecting forward of the cutting edge of the blade, the elements having skin protective portions to contact the skin immediately in front of the blade and substantially tangentially to the blade. the cutting edge of the blade.

2. A blade unit for razors according to claim 1, characterized in that the elements projecting forward are integral with the blade holder.

3. A blade unit for razors according to claim 1 or 2, characterized in that the elements have upper surface portions extending, viewed laterally in plan, in a rectilinear form with respect to a point separated from the edge of the blade, at a distance (A) in the range of 0.10 to 0.30 mm.

4. A blade unit for razors according to claim 3, characterized in that the length of the rectilinear surface portion is equal to several times the distance between said surface portions and the edge of the blade.

5. A blade unit for razors according to any of claims 1 to 4, characterized in that at its front ends, the upper surface portions emerge gradually with rounded nose portions of the elements.

6. A ho-ho unit for shaving machines according to any of claims 1 to 5, characterized in that the elements have flat sides and the side edges of the upper surface portions emerge gradually with radiating or diverging flanking surfaces extending from the flat sides.

7. A blade unit for razors according to any of claims 1 to 6, characterized in that the elements have a width of 0.1 to 0.3 mm.

8. A ho-ho unit for shaving machines according to claim 7, characterized in that the width of the upper surface portions is not greater than 0.15 mm.

9. A blade unit for shaving machines according to any of claims 1 to 8, characterized in that the elements are arranged longitudinally with respect to the blade, with a separation of less than 2 mm.

10. A blade unit for razors according to claim 9, characterized in that the separation of the elements, longitudinally with respect to the blade, is in the range of 0.5 to 1.5 mm.

11. A blade unit for razors according to claim 10, characterized in that the spacing is substantially equal to 1.0 mm.

12. A blade unit for razors according to any of claims 1 to 11, characterized in that behind the portions that come into contact with the skin, the elements have lower portions with inclined upper faces to follow the sheet on the side bottom of it.