WO2001008856A1

WO2001008856A1 - Improved shaving system

Info

Publication number: WO2001008856A1
Application number: PCT/US2000/020948
Authority: WO
Inventors: Mingchih M. Tseng; Cheng-Jih Li; Alfred Porcaro; Kevin L. Powell
Original assignee: The Gillette Company
Priority date: 1999-08-03
Filing date: 2000-08-01
Publication date: 2001-02-08
Also published as: AU6394700A

Abstract

A shaving system including a holder, and a blade member secured to said holder. The blade member has at least one nonlinear sharpened edge with a tip radius less than 400 Å. Also disclosed is blade member that is curved about a longitudinal axis and has a field of apertures defining annular sharpened edges. Also disclosed is a blade member with a field of aperture having different amounts of upturn (or in some cases some apertures could have no upturn).

Description

IMPROVED SHAVING SYSTEM

The invention relates to shaving systems including a blade member with annular sharpened edges .

Shaving systems with a plurality of apertures and a thin metal foil to define annular sharpened edges have been proposed, e.g., in U.S. Patent No. 5,088,195 and the references cited therein. That patent, which is hereby incorporated by reference, describes a shaving system including a holder and a blade member that has a plurality of apertures defining annular sharpened edges that are upturned to. have the cutting edges raised above the shaving plane of the upper surface of the metal foil. The patent describes an edge height of 0.01 to 0.1 mm (10-100 microns) .

In one aspect, the invention features in general, a shaving system including a holder and a blade member having a nonlinear sharpened edge having a tip radius less than 400 Angstroms (A) .

Particular embodiments of the invention may include one or more of the following features. There are a plurality of sharpened edges provided by a plurality of apertures. The sharpened edges have a tip radius below 300 A and preferably between 150 A and 200 A. The edges have a height between 1 and 20 microns (preferably between 5 microns and 15 microns) .

In another aspect, the invention features, in general, a shaving system including a holder, and a blade member including a field of apertures secured to the holder. The blade member has a length along a longitudinal axis and a width and a curvature about an axis parallel to the longitudinal axis (e.g., as shown in Fig. 6) . The apertures have sharpened edges with a tip radius below 400 A. Particular embodiments of the invention may include one or more of the following features. The edges have a tip radius below 300 A (preferably between 150 A and 200 A) . The blade member has an average radius of curvature about the axis parallel to a longitudinal axis between 1 and 5 inches, preferably between 1 1/2 and about 2 inches. It can also have a curvature about an axis parallel to a width axis that is greater than 2" (preferably 5" or greater) . The field of apertures has between 10 and 50 apertures. In another aspect, the invention features, in general, a shaving system including a holder, and a blade member secured to the holder. The blade member has a field of apertures defining annular sharpened edges. The apertures have different amounts of upturn (or in some cases some apertures could have no upturn) , depending upon the location of the apertures in the field.

Particular embodiments of the invention may include one or more of the following features. One area of the field has apertures with sharpened edges that are upturned so as to curve upward, and another area of the field has apertures with sharpened edges that have not been upturned. The blade member is curved about an axis parallel to a width axis (e.g., as shown in Fig. 1) . In some preferred embodiments, the area without the upturned edges is at a central area, and there are upturned edges in areas at both sides of the central area. Alternatively, there could be less upturn at the apertures in the central area, and more upturn at the side areas. There could also be gradual change in the amount of upturn in an area or across the field. The blade member has an average radius of curvature about an axis parallel to the width axis that is greater than 2" (preferably 5" or greater) . The apertures at the central area can have uplifted (i.e., raised but not curved⁾ or flat edges. Having more upturn at the side areas of a curved blade member and less (or no) upturn in a central area provides a closer shave where it is needed and avoids irritation at the central region where the shaving force tends to be greater.

In some particular embodiments, the upturn edges are provided only in an outer ring of apertures; alternatively, upturn edges can be provided only in the two outer rows . In some other embodiments apertures are provided with upturn only on one side of each aperture; e.g., only on the outer edge portions of the two outer rows. The upturned portions could all also be directed in the same direction in a razor that has directional shaving.

Embodiments of the invention may include one or more of the following advantages. The use of tip radius below 400 A (preferably less than 300 A and most preferably between 150 A and 200 A) provides for improved shaving.

In another aspect, the invention features, in general a shaving system including a holder and a blade member with a field of apertures. The blade member has a length and a width along a width axis, and a curvature about an axis parallel to the width axis (e.g., as shown in Fig. 1) . The apertures define annular sharpened edges with a tip radius below 400 A. The apertures can have a uniform amount of upturn.

Other advantages and features of the invention will be apparent from the following description of a preferred embodiment thereof and from the claims .

Fig. 1 is a perspective view of a shaving system.

Fig. 2 is a partial vertical sectional view through an aperture with an annular sharpened cutting edge of the Fig. 1 shaving system. Fig. 3 is an enlarged partial sectional view of a cutting edge of an aperture with an uplifted edge in a central area of the blade member of the Fig. 1 system.

Fig. 4 is an enlarged sectional view of a sharpened annular cutting edge of an aperture with an upturned edge in a side area of the blade member of the Fig. 1 system.

Fig. 5 is a perspective view of an alternative embodiment of a shaving system.

Fig. 6 is a perspective view of a further alternative embodiment of a shaving system.

Referring to Fig. 1, there is shown shaving system 10 including handle portion 12 that is secured to cap portion 14. Curved metal foil strip 16 is secured to cap portion 14 and has an array of 28 apertures 18 divided into three areas: central area 40, and side areas 42. Skin conditioning member 19 extends around foil strip 18. Shaving system 10, e.g., can have a height of about 6.5 cm, a width of about 5.7 cm and a thickness of about^' 2.4 cm. Referring to Figs. 1 and 2, metal foil strip 16 is, e.g., manufactured of 0.1 mm thick strip steel and has a length of about 4.0 cm and a width of about 1.5 cm. The steel has 0.4% carbon, 13.5% chromium, 1.25% molybdenum, 0.37% manganese, 0.35% silicon, and the balance iron with incidental impurities. Circular apertures 18 are disposed in three rows that are spaced about 4 mm on center. Each aperture 18 has a diameter of about 3 mm and a circular sharpened edge 20. Alternatively, other numbers of rows, e.g., two or four rows, could be used, and the apertures could be between 1.0 mm and 5 mm in diameter. Also, there could be different numbers of holes; e.g., instead of 28 holes (as in Fig. 1), there could be 25 holes (as in Figs. 5 and 6) , or 22 holes in a three-row design. The body of strip 16 has upper surface 22 and lower surface 24. Surrounding each aperture are annular portions 26, 28 that are inclined with respect to surfaces 22 and 24. Each hole is also surrounded by ground surface 31, which begins at plane 30 (indicated by dashed lines on Figs. 2-4) and is inclined upward to sharpened edge 20. Some upper inclined portions 26 have a sharpened edge 20 that is an uplifted edge 44, as shown in Fig. 3, while others have the ultimate edge 20 turned up further in upturned edge 46, as shown in Fig. 4. (Figs. 3 and 4 are enlarged partial views of the portion indicated by 33 on Fig. 2.) Apertures in central area 40 have uplifted edges 44, whereas apertures in side areas 42 have upturned edges 46. (Alternatively, central area 40 could have flat edges. Alternatively, there could be less upturn at the apertures in the central area, and more upturn at the side areas. There could also be gradual change in the amount of upturn in an area or across the field.) The height h_x of uplifted edge 44, measured from plane 30, is about 7 microns. The height h₂ of upturned edge 46, measured from plane 30, is about 10 microns. The tip radius for edges 44, 46 is below 400 A, and preferably below 300 A (and most preferably 150 A - 200 A) . Uplifted edges 44 and upturned edges 46 could also have heights between 5 microns and 20 microns (preferably between 5 microns and 15 microns) .

The foil apertures with sharpened edges are made by a process of piercing, dimpling, hardening, sharpening, deburring, electropolishing, telomer spraying, and sintering to provide flattened or uplifted edges, and potentially further pressing to provide upturned edges. The last step only applies to the apertures in the side regions for the Fig. 1 embodiment; the last step may or may not also apply to the Figs. 5 and 6 embodiments, described below. A press is used to pierce the apertures at 2.8 mm diameter, and then dimple the apertures to a dimpling height of about 0.20 mm and about 20° dimpling angle. The individual blades are then cut from the strip of metal and provided with an curve about an axis parallel to the width dimension of the foil for the Fig. 1 embodiment. The radius of curvature about an axis parallel to a width axis is about 5" in the Fig. l embodiment. It should be greater than 2" and preferably is 5" or greater. As a result of processing, the apertures are not perfectly round, but can vary somewhat in circularity and tend to be slightly oblong. The tip radius can also vary somewhat at different locations. The tip radius is less than 400 A, and preferably less than 300 A. Most preferably the tip radius is between 150 A and 200 A.

The height of edges can be determined using a three- dimensional imaging surface structure analyzer. Tip radius can be determined using scanning electron microscopy. Upturned edges 46 provide a closer shave than uplifted edges 44. Central area 40 tends to have more shaving force than side areas 42. Having the upturned edges 44 in the side portions only, provides less irritation and improved shaving closeness .

Referring to Fig. 5, there is shown shaving system 110 including handle portion 112 that is secured to cap portion 114. Flat metal foil strip 116 is secured to cap portion 114 and has an array of apertures 118, which have the same diameter and tip radius as described for the Fig. 1 embodiment. Apertures 118 can have uplifted edges or upturned edges as described above.

Referring to Fig. 6, there is shown shaving system 210 including handle portion 212 and metal foil strip 214, which has an array of apertures 216. Skin conditioning member 218 extends around foil strip 214. Metal foil strip 214 has a curvature about an axis that is parallel to the longitudinal axis of foil strip 216. Apertures 216 have uplifted edges as shown in Fig. 3 and described above. (Alternatively, apertures 216 could have flat edges.) Apertures 216 have the same diameter and tip radius as described for the Fig. 1 embodiment. Metal foil strip 214 is provided with apertures 216 while the strip is flat, as described above. Strip 214 is thereafter provided with a curve about an axis parallel to a length axis and is mounted on handle portion 212. Metal foil strip 214 has a radius of curvature between 1 and 5 inches, preferably between 1 1/2 and about 2 inches. Metal foil strip 214 can also be provided with a curvature in the transverse direction about an axis parallel to a width axis; this transverse curvature should preferably have a radius of curvature greater than 5" (most preferably greater than 15"). The apertures could also be provided with upturned and/or uplifted edges.

Other embodiments of the invention are within the scope of the appended claims. For example, in the Figs. 1, 5 and 6 embodiments, the upturn edges could be provided only in an outer ring of apertures, or upturn edges could be provided only in the two outer rows . The interior apertures could have uplift. Also, apertures could be provided with upturn only on one side of each aperture_? e.g., upturn could be provided only on the outer edge portions of the two outer rows. There could be a height of about 15 microns at the upturned portion and a height of about 5 microns at the remainder of the aperture. The upturned portions could all also be directed in the same direction in a razor that has directional shaving. Apertures could also be provided with uplift at only exterior apertures.

Claims

1. A shaving system comprising a holder, and a blade member secured to said holder, said blade member having at least one nonlinear sharpened edge having a tip radius below 400 A.

2. The shaving system of claim 1 wherein said nonlinear sharpened edge is an annular sharpened edge.

3. The shaving system of claim 2 wherein said annular sharpened edge is formed at an aperture in a sheet of metal .

. The shaving system of claim 1 wherein said blade member has a plurality of said nonlinear sharpened edges defined by apertures having annular sharpened edges having a tip radius less than 300 A, said apertures being in a field of apertures .

5. The shaving system of claim 4 wherein said apertures have a diameter of about 1.0 mm to 5.0 mm.

6. The shaving system of claim 1, 2 or 4 wherein said tip radius is between 150 A and 200 A.

7. The shaving system of claim 1 , 2 or 4 wherein said edges have a height between 1 and 20 microns.

8. The shaving system of claim 1, 2 or 4 wherein said edges have a height between 5 microns and 15 microns.

9. The shaving system of claim 4 wherein said field of apertures includes between 10 and 50 apertures.

10. A shaving system comprising a holder, and a blade member secured to said holder, said blade member including a field of apertures, said blade member having a length along a longitudinal axis and a width, said blade member having a curvature about an axis parallel to said longitudinal axis, said apertures defining annular sharpened edges with a tip radius below 400 A.

11. The shaving system of claim 10 wherein said tip radius is below 300 A.

12. The shaving system of claim 10 wherein said blade member has an average radius of curvature between 1" and 5" .

13. The shaving system of claim 12 wherein said radius of curvature between 1 1/2" and 2".

14. The shaving system of claim 13 wherein said blade member also has a second curvature about a width axis that is transverse to said longitudinal axis with a radius of curvature greater than about 2".

15. The shaving system of claim 13 wherein said blade member also has a second curvature about a width axis that is transverse to said longitudinal axis with a radius of curvature greater than 5".

16. The shaving system of claim 12 wherein said field of apertures has between 10 and 50 apertures.

17. The shaving system of claim 11 wherein said tip radius is between 150 A and 200 A.

18. The shaving system of claim 11 wherein said apertures have a diameter of about 1.0 mm to 5.0 mm.

19. The shaving system of claim 11 wherein said apertures have upturned edges .

20. A shaving system comprising a holder, and a blade member secured to said holder, said blade member having a field of apertures, at least some apertures having upturn and other apertures having less or no upturn depending upon the location of the apertures in the field.

21. The shaving system of claim 20 wherein said field includes first and second areas, said first area having apertures with sharpened edges that are upturned, said second area having apertures with sharpened edges that are not upturned.

22. The shaving system of claim 21 wherein said blade member has a length and a width along a width axis, said blade member is curved about an axis parallel to said width axis, said second area is at a central area, said first area is at one side of said central area, and a third area of said field is on the other side of said central area and has apertures with sharpened edges that are upturned, said curvature being greater than about 2".

23. The shaving system of claim 21 wherein said curvature has a radius of curvature greater than 5" .

24. The system of claim 21 wherein said apertures at said central area have uplifted edges.

25. The shaving system of claim 21 wherein said edges have a tip radius below 400 A, and a height between ₁ microns and 20 microns.

26. The system of claim 24 wherein said uplifted edges and said upturned edges have a tip radius below 300 A, and said uplifted edges and upturned edges have a height between 5 microns and 20 microns.

27. The system of claim 20 wherein said edges have a tip radius between 150 A and 200 A.

28. The shaving system of claim 20 wherein said field of apertures includes between 10 and 50 apertures.

29. The shaving system of claim 20 wherein said apertures have a diameter of about 1.0 mm to 5.0 mm.

30. The shaving system of claim 20 wherein some apertures have a first amount of upturn and other apertures have lesser upturn.

31. The shaving system of claim 30 wherein the amount of upturn gradually changes.

32. A shaving system comprising a holder, and a blade member secured to said holder, said blade member including a field of apertures, said blade member having a length and a width along a width axis, said blade member having a curvature about an axis parallel to said width axis, said apertures defining annular sharpened edges with a tip radius below 400 A.

33. The shaving system of claim 31 wherein said tip radius is below 300 A.

34. The shaving system of claim 32 wherein said curvature has a radius of curvature greater than about 2 " .

35. The shaving system of claim 34 wherein said radius of curvature is greater than 5".

36. The shaving system of claim 32 wherein said field of apertures has between 10 and 50 apertures.

37. The shaving system of claim 32 wherein said tip radius is between 150 A and 200 A.

38. The shaving system of claim 32 wherein said apertures have cutting edges with a uniform amount of upturn.

39. The shaving system of claim 4, 10, 20, or 32 wherein said field of apertures includes exterior apertures at the periphery of said field and internal apertures inside the periphery, and wherein the exterior apertures have upturn and the internal apertures do not have pturn.

40. The shaving system of claim 4, 10, 20, or 32 wherein said field of apertures includes exterior rows of apertures and an internal row of apertures between the exterior rows, and wherein the apertures in the exterior rows have upturn and the apertures in the interior row do not have upturn.

41. The shaving system of claim 4, 10, 20, or 32 wherein at least some said apertures have upturn only at upturn portions of said annular sharpened edges of said apertures .

42. The shaving system of claim 4, 10, 20, or 32 wherein said field of apertures includes at least some said apertures have upturn only at upturn portions of said annular sharpened edges of said apertures, upturn portions of apertures in the same row being oriented in the same direction.

43. The shaving system of claim^' 4 , 10, 20, or 32 wherein said field of apertures includes at least some said apertures have upturn only at upturn portions of said annular sharpened edges of said apertures, said upturn portions of said apertures all being oriented in the same direction.

44. The shaving system of claim 4, 10, 20, or 32 wherein said field of apertures includes exterior apertures at the periphery of said field and internal apertures inside the periphery, and wherein the exterior apertures have upturn and the internal apertures have uplift.

45. The shaving system of claim 4, 10, 20, or 32 wherein said field of apertures includes exterior rows of apertures and an internal row of apertures between the exterior rows, and wherein the apertures in the exterior rows have upturn and the apertures in the interior row have uplift.

46. The shaving system of claim 4, 10, 20, or 32 wherein said field of apertures includes exterior apertures at the periphery of said field and internal apertures inside the periphery, and wherein the exterior apertures have uplift and the internal apertures do not have uplift.

47. The shaving system of claim 4, 10, 20, or 32 wherein said field of apertures includes exterior rows of apertures and an internal row of apertures between the exterior rows, and wherein the apertures in the exterior rows have uplift and the apertures in the interior row do not have uplift.

48. The shaving system of claim 4, 10, 20, or 32 wherein said field of apertures includes at least some said apertures that have uplift.