KR970003483B1 - Providing cutting edges on razor blade or the like - Google Patents

Abstract

none

Description

Apparatus and method for forming a cutting edge of a razor blade

1 is a schematic side view of the device of the invention used to make a razor blade;

2 is a schematic plan view of two abrasive wheels employed in a preferred embodiment of this invention;

3 is a schematic side view of the two abrasive wheels of FIG. 2;

4 is a schematic right end view of the two abrasive wheels of FIG. 2;

5 is an enlarged view of a blade cutting surface shape manufactured according to an embodiment of the present invention;

FIG. 6 is an enlarged view of a blade cutting face shape made according to the embodiment of US Pat. No. 3,461,616;

FIG. 7 is an exemplary schematic plan view of FIGS. 2-4 abrasive wheels, showing variations in the degree of polishing provided by the abrasive cars;

8 is a schematic illustration of the polishing performed on the cross section of the blade strip material by the fourth polishing wheels;

9 is a diagram illustrating the contour and mounting of the FIG. 2 abrasive wheels; FIG. And

10 is a detailed side view of an exemplary arrangement of the inventive device used to make a razor blade.

* Description of the symbols for the main parts of the drawings *

12: upper edge 12a: lower edge

16,18 grinding part 20,20 grinding wheel

28: inlet end 30: outlet end

50: cutting surface 54: cutting edge

56: rough honing mask 32: spindle

40: ridge 42: polishing surface

44: nip 70-76: part

The present invention relates to a novel and improved method and apparatus for forming a cutting surface in a cutting mechanism, and more particularly, to a novel and improved method and apparatus for manufacturing a blade or the like.

Razor blades are currently manufactured by continuous high speed mass production techniques involving multiple continuous grinding operations to form a cutting surface comprising cutting edges. Each polishing operation forms a surface on both sides of the cutting surface, which surface may or may not be changed by continuous polishing operations. Typically, at least three polishing operations are required to form the surfaces forming the cutting surface of the final razor blade. The first operation is a grinding operation and involves grinding both sides of a continuous sheet of metal to form a first or grinding surface on both sides. The metal sheet is then subjected to a rough honing operation to form a second or coarse honing mask on both sides, and the final honing operation forms cutting edge surfaces on both edges of the blade. Further details regarding current commercial blade manufacturing processes and apparatus can be found in co-owned US Pat. No. 3,461,616. As disclosed in the patent, continuous metal strips undergo computational, coarse honing and final honing operations to form convex cutting edges. In particular, US Pat. No. 3,461,616 is provided here by reference only.

The processes and apparatus disclosed in US Pat. No. 3,461,616 have made significant progress in the high speed continuous manufacture of razor blades. Basically the disclosed processes and apparatus comprise three conventional grinding operations, namely grinding, rough honing and final honing. In the grinding operation, one of the edge surfaces of the razor blade metal strip is polished first and the other opposite surface is later polished to provide the grinding surface of the cutting surface. In the rough honing operation and the final honing operation, both sides are polished at about the same time because the associated polishing means comprise two parallelly arranged polishing wheels. A new and unique feature of the processes and apparatus of US Pat. No. 3,461,616 is the final honing operation. In this operation, both sides of the cutting edge of the razor blade, which provides the cutting edge, are polished by grinding means. The edges are arranged to be suitable for grinding with the angles gradually decreasing. The final honing operation of US Pat. No. 3,461,616 provides several outstanding advantages to commercial razor blade manufacturing processes. The most significant advantage is that it can increase the production rate of the blade by about 5 times or more.

In the processes and apparatus of US Pat. No. 3,461,616, grinding was found to be a factor influencing the overall efficiency of the production process. Often the grinding operation produces sharp projections at the edges of the grinding surface, which removes more of the abrasive surfaces in the inlet area of the grinding means forming a rough honing face. In addition, automatic monitoring and adjustment means are typically arranged between the grinding portion and the rough honing portion to detect the irregularities of the grinding surfaces and send an appropriate adjustment signal to the grinding portion to compensate for the detected irregularities. These monitoring and coordination measures are expensive and very complex and can have a limited impact on production rates. Thus, while the processes and apparatus of US Pat. No. 3,461,616 are very efficient and cost effective, there is still room for improvement in processes and apparatus that provide maximum efficiency and cost effectiveness for mass production of razor blades with advanced performance characteristics. There is. The present invention has been undertaken in accordance with such necessity and most effectively copes with it.

This invention proposes new and improved processes and apparatus which are particularly suitable for shaving blades and which form cutting surfaces in a cutter.

Basically these new processes and apparatus are intended to polish a portion of both sides selected to support the cutting surface and form rough honing surfaces on the cutting surface. Grinding is related to the grinding means, which first polish the faces simultaneously with relatively high roughness and relatively small angles, then gradually reduce the roughness and gradually increase the angles. At the same time has the ability to polish. In this way, the surfaces of the metal strip are initially ground, but as polishing continues across the axial length of the metal strip, the surfaces are subjected to rough honing to form rough honing faces on the final polishing surfaces. Cutting edge facets can be formed at both end faces thereof by known final honing operations. Thus, the razor blade of this invention has a cutting surface formed by rough honing face and final honing face on both sides.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 shows an arrangement of a device suitable for forming a cutting surface at one edge of a razor blade according to an embodiment of this invention.

The blade stock in the form of a thin metal strip 10 having a constant width having an upper edge 12 and a lower edge 12a is arranged so that both sides of the upper edge 12 are polished with the grinding portions 16 and 18. It is arranged to be driven along a path forming one side 14 for movement.

The polishing section 16 includes two polishing wheels 20 and 22 (FIGS. 2-4). Each abrasive wheel 20, 22 may predominantly rotate the axes 24, 24a (FIG. 4) of spaced apart coplanar (preferably parallel) forming a plane. These axes 24, 24a are arranged to form an angle 26 (inclined angle) between the plane of the axes 24, 24a and the path of the upper edge 12 (ie the plane 14). Preferably, the abrasive wheels 20, 22 are arranged in parallel and joined together, with relatively high roughness on both sides of the strip 10 close to the edge 12 and of the inlet ends 28 (FIG. 2). The angle is relatively small and the ability to polish at the same time. Thereafter, as the strip 10 is moved from the inlet ends 28 toward the outlet ends 30 of the abrasive wheels 20 and 22, the abrasive wheels are gradually reduced in roughness and angled at their face portions. Polish at the same time to gradually increase.

When both surfaces are polished in the polishing section 16, rough honing face 56 is formed on both sides of the cutting face 50 (FIG. 5), and the angle of the face increases in distance from the cutting edge 54. FIG. Gradually decrease.

After exiting the polishing section 16, the strip 10 is moved to the polishing section 18 in which cutting edge facets 52 (FIG. 5) are formed on both sides of the cutting surface 50 (FIG. 5). . The cutting edge faces 52 may be formed of a known type of device, such as two parallelly arranged polishing wheels that are rotationally mounted and arranged to polish both sides of the upper edge 12.

Preferably, the cutting edge masks are formed according to the processes and apparatus disclosed in the above-mentioned reference US Pat. No. 3,461,616. The final razor blade consists of two facets on each opposing face of the cutting face 50. These masks are shown in FIG. 5 as rough honing surfaces 56 and cutting edge surfaces 52. Representative dimensions of both sides of the blade cutting surface 50 produced in accordance with an embodiment of this invention are between about 0.010 mm (0.0254 cm) -about 0.025 mm (0.0635 cm). Representative dimensions of the cutting edge masks 52 are between about 0.0006 mm (0.00152 cm) -about 0.008 mm (0.0203 cm), while rough dimensions of the rough honing surfaces 56 are about 0.002 mm (0.005 cm)- About 0.0244 cm (0.0620 cm).

In Figures 2-4, the abrasive wheels 20, 20 rotate about spaced parallel axes 24, 24a so that the plane of the axes 24, 24a and the path of the upper edge 12 are rotated. Is a modified truncated cone mounted to provide an angle of inclination 26. Each abrasive wheel is mounted on a spindle 32 comprising bearing mounts 34, 36 with a drive gear 38, the drive gear being located on each spindle between the bearing mount and the abrasive wheel. Spindle 32 is mounted to rotate in a suitable bearing block (not shown).

Spiral spirals formed on the circumferential surface of each polishing wheel form a plurality of container portions 40 which provide or support the polishing surface 42. This polishing surface 42 may be any of a known class of abrasives, such as diamond, among carbides, nitrides, alumina or others suitable for polishing razor blade metals. Preferably the abrasive wheels are joined to each other to form a nip 44 (FIG. 4), which passes through the strip 10 and is shown in the holder 46 as well shown in FIG. Is supported by. The diameter of each polishing wheel varies over the length so that each polishing wheel is effectively inclined so that the angle between the polishing surfaces 42 of the nip 44 also spans the axial length of the polishing wheels 20 and 22 coupled to each other. Variable. The diameter of the polishing wheels 20 and 22 is the minimum at the inlet ends 28, and the diameter of the polishing wheel thereafter is the outlet ends 30 over the length of the polishing wheel, although the polishing sweep angle of the inlet end 28 is relatively small. Gradually increasing toward the outlet ends 30 to increase gradually). Representatively illustrated relatively small abrasive angles are between about 10 ° to about 170, and the small angles are gradually increased to about 14.5 ° to about 21.5 °. Abrasive wheels 20 and 22 diameters representatively illustrated at the inlet ends 28 are between about 4.5 mm (11.43 cm) to about 0.6 mm (16.51 cm), and are representatively illustrated at exit ends 30. The wheel diameter is between about 4.6 mm (11.68 cm) and about 6.6 mm (16.76 cm).

As shown in FIG. 7, each polishing wheel is divided into portions 70, 72, 74, and 76 to provide different roughness to the polishing surfaces 42 of each portion. The roughness of the polishing surfaces 42 at the portion 70 is relatively high, while the roughness of the polishing surfaces 42 at the portions 72, 74, 76 gradually decreases. In this way both sides of the strip 10 are roughened at the inlet ends 28 which polish the surfaces to form temporary grinding surfaces on the surfaces, and the temporary grinding surfaces exit at the exit ends 30. It is gradually changed over the length of the abrasive wheel to form rough honing masks on both sides.

For the polishing operations of the polishing wheels 20, 22, see FIG. 8, which roughly shows the polishing operation performed on the cross section of the strip 10 by the portions 70, 72, 74, 76 (FIG. 7). Will be better understood. As can be seen, the portion 70 that provides a relatively high roughness with a relatively small polishing angle removes the pieces 170 to form grinding facets. However, portions 72, 74, and 76 gradually reduce the roughness and gradually increase the abrasive angles, thereby removing the pieces 172, 174, and 176, respectively, to form rough honing surfaces on both edges. Thus, the polishing operation of the polishing wheels 20 and 22 effectively merges the grinding surface and the rough honing surface in a single operation. The appearance of the final rough honing face depends on the differences present between the polishing angles provided by each of the portions 70-76 or on the differences between the roughness provided by each portion. Visually, the final rough honing face formed on both sides of the cut surface 50 appears to have a continuous surface of the face.

In close-up, it appears that a significant portion of the rough honing masks formed by this embodiment of the invention consists of a plurality of narrow individual adjacent masks. However, in a preferred embodiment of this invention, the width of adjacent individual facets is not so easily detected when enlarged and so narrow that coarse honing facets can actually appear as continuous surfaces. In some cases, the final coarse honing face is a convex surface where the angle of face gradually decreases as the distance from the cutting edge 54 (FIG. 5) increases. In a preferred embodiment of this invention, the final rough honing face, as shown in FIG. 5, has a convex surface where the angle of angle gradually decreases almost continuously as the distance at the cutting edge 54 increases.

Differences between the razor blade produced according to the embodiment of the present invention and the razor blade produced by known production techniques will be well understood with reference to FIGS. 5 and 6. 6 schematically illustrates the shape of the cutting surface 50a of a razor blade produced according to US Pat. No. 3,461,616. As shown in FIG. 6, the cutting surface 50a includes cutting edge facets 52a on both sides thereof. Cutting edge surface 52a is a convex surface in which the angle of convexity gradually decreases as the distance from cutting edge 54a increases.

The cutting surface 50a also includes coarse honing and rough surfaces unique to both sides. The angles of these masks are basically straight and become smaller for each mask as the distance from the cutting edge 54a increases. Thus, the cutting surface 50a is formed by the grinding operation, the rough honing operation and the final honing operation. There are three visually distinct masks. In contrast, the cutting face 50 of FIG. 5 comprises only two facets on both sides: rough honing face 56 and cutting edge face 52, both of which face cutting edge 54. As the distance from Es increases, their angle is gradually convex. The cutting face formed on both convex sides is connected with a relatively thin cutting edge with improved cross-sectional strength for the cutting face, providing improved performance characteristics in terms of shaving and durability.

As explained, the plane of the axes 24, 24a and the path of the edge 12 are arranged to form an inclination angle 26. As shown in FIGS. 3 and 4, the inclination angle 26 is opposite to the inclination angle of the polishing wheels shown in FIGS. 3 and 4 of US Pat. No. 3,461,616. The combination of the inclination angle and the design features of the polishing means of the present invention cooperate to allow for a very efficient and rapid removal of the metal in the manner shown in FIG.

As shown in FIG. 8, the polishing operation achieved by the cooperation between the inclination angle and the polishing means removes metal on both sides of the strip 10. As shown in FIG. In this way, as both sides are moved toward the exit end 30 of the polishing wheels 20 and 22, the metal is gradually gradually removed from both sides. Thus, the parts with greater roughness 70,72 are arranged to achieve the maximum effect in performing the function designed to remove a greater amount of metal. Smaller roughness portions 74 and 76 remove less metal, and the sharp polishing operation of these portions is gradually directed towards the edge.

The polishing operation achieved through the cooperation between the inclination angle and the design features of the polishing means causes the strip 10 to move through the polishing wheels 20 and 22 at higher speeds. The inclination angle 26 may vary widely depending on several factors, including the length or diameter of the polishing wheels, or the orientation of the polishing wheel axes, or the variation of the polishing angle or the desired roughness of the polishing wheel portions. have.

Suitable reverse tilt angles 26 illustrated are between about 0.3 ° to about 10 °, preferably between about 0.5 ° -5 °.

9 is a diagram showing the inclination angle 26 of one polishing wheel 20 or 22 with respect to the path of the blade 10 edge 12. As shown, the inlet circumference of the polishing wheel at the inlet end 28 is indicated by an arc or ellipse 60, and the outlet circumference of the polishing wheel at the outlet end 30 is indicated by an arc or ellipse 62. The path of the cutting edge (and the plane 14) is perpendicular to the line 66 and the drawing.

The axis 24 or 24a of the polishing wheel is indicated by line 68, the longitudinal position of the axis 24 at the polishing wheel inlet end 28 is indicated by point C, and the axis 24 at the outlet end 30. Or the position of 24a) is indicated by point A.

Further details of particularly preferred embodiments of this invention are set forth in the following illustrative, non-limiting examples.

Example 1

Particularly preferred arrangements of the devices used in this embodiment are described in relation to the first, second, third, seventh and tenth degrees. As shown, the polishing portion 16 comprises two parallelly arranged interconnected spiral wheels comprising a spiral wheel 20, the spiral wheel 20 being shown in FIGS. 2, 3, 10 degrees. As is arranged to be connected to each other with the other spiral wheel (22). Multi-helical wheels, such as double, triple, quadruple spiral wheels, are preferred because they can remove the metal completely uniformly without sharp projections, and also allow the wheel to wear in balance. In addition, multi-threaded wheels impart more stringent nip operation at greater normal forces on abrasive particles, resulting in more metal removal and higher razor blade speeds. Moreover, tighter nips can reduce wheel wear effects. Each wheel 20,22 is between about 6.5 mm-about 7.5 mm (16.51 cm-19.05 cm) in length, and has an inlet diameter of about 6.0 mm (15.24 cm) -about 5.75 mm (14.61 cm) and exits The diameter is about 6.05 mm (15.37 cm) to about 5.80 mm (14.73 cm), and the overall slope (hyperbolic) is between about 0.02 mm (0.051 cm) to about 0.05 mm (0.127 cm) per side, or about 0.01 mm ( 0.0254 cm) -about 0.025 mm (0.0635 cm).

The axes 24, 24a of each wheel are arranged in a common plane to form an inclination angle 26 of about 0.75 ° to about 1.25 ° with respect to the path of the edge 12. This inclination angle forms an inlet polishing angle between about 5.5 ° and about 8 ° at the inlet end 28 and an exit polishing angle between about 8.0 ° and about 10.0 ° at the delivery end 30 for each wheel.

Each wheel 20, 22 is divided into four parts as shown in FIG. Preferred abrasives for use with the wheels 20 and 22 are resin or vitrified bonded cubic fluorine nitride.

Preferably, the portion 70 (FIG. 7) adjacent to the inlet end 28 includes about 6-8 ridges 40, each ridge 40 supporting the polishing surface 42. This abrasive surface comprises a resin-bonded abrasive having particles having an average size of between about 50 microns and about 70 microns, providing a relatively high roughness to the portion 70. Preferably, portion 72 includes about 5-6 ridges 40 that support the polishing surface 42 on each side, the polishing surface having particles having an average size of between about 20 microns and about 40 microns. Resin-bonded abrasives are included. Portion 74 also preferably includes about 3-4 ridges 40.

The resin-bonded abrasive of each polishing surface 42 of the portion 74 has particles having an average size of about 10 µ to about 20 µ.

The portion 76 also preferably includes about 0.5-2 ridges 40, wherein each polishing surface 42 of the portion 76 has a resin-bonded abrasive having particles having an average size of between about 5 microns and about 7 microns. It includes. The preferred width of the polishing surface 42 is between about 0.1 mm (0.254 cm) and about 0.2 mm (0.508 cm).

The face shape of each of the wheels described above has been substantially modified in accordance with the methods disclosed and claimed in US Pat. No. 3,566,854, which is co-owned to form a nearly straight intersection between the two wheels. US Patent No. 3,566,854 is also incorporated herein by reference in its entirety. The two wheels are mounted on the bearing blocks of the polishing part 16 such that their axes are parallel and inclined to form a reverse tilt angle 26 of about 1 ° with respect to the plane 14.

When lubricant is injected into the wheels, the wheels are quietly transported into the upper edge 12 to determine the correct polishing head setting.

The setting of the spindle 32 is then adjusted to make uniform contact with the cutting edge over the entire length of the wheels.

In a preferred embodiment of this invention, the polishing section 18 comprises the final honing polishing means of US Pat. No. 3,461,616. Representatively preferred final honing polishing means comprise two paralleled interconnected spiral wires comprising a wheel 120, the wheel 120 having another parallel arrangement in the manner described and shown in US Pat. No. 3,461,616. Interconnected wheels are arranged. Each wheel is between about 2.5 mm (6.31 cm) and about 3.5 mm (8.89 cm) in length, and includes about 5-7 ridges 140, each ridge 140 having a polishing surface 142. This polishing surface comprises a hard resin-bonded metal oxide abrasive having particles having an average size of between about 7 microns and about 9 microns. The inlet diameter of each wheel is between about 6.0 mm (15.24 cm) and about 5.5 mm (13.97 cm), and the outlet diameter is between about 5.9 mm (14.99 cm) and about 5.4 mm (13.72 cm), and the overall slope of each wheel Hyperbolic is between about 0.09 mm (0.23 cm) -about 0.11 mm (0.28 cm) or about 0.045 mm (0.114 cm) -about 0.055 mm (0.140 cm) per side.

The axes 124 of the wheels 120 and the interconnected spiral spiral wheel 122 (not shown) are at an angle of inclination 126 between about 4.5 ° and about 5.5 ° relative to the path of the upper edge 12. Are arranged to form.

This inclination angle forms an inlet polishing site angle between about 26 ° and about 32 ° at the inlet ends 128 for each wheel, and an exit polishing site angle between about 16 ° and about 20 ° at the outlet ends 130. .

Each wheel is mounted on a spindle 132 that includes bearing mounts 135, 136, and a drive gear 138 is arranged on each spindle between the bearing mounts and the wheels. Spindle 132 is mounted to rotate on appropriate bearing blocks (not shown). The diameter of each wheel varies over its length so that each wheel is effectively inclined. Thus, the polishing angle between the polishing surfaces 142 in the nip formed between the interconnecting wheels varies with the length of the interconnecting wheel 122 arranged in parallel with the wheel 120. As described, the polishing angle of the inlet ends 128 of the wheels is greater than the polishing angle of the outlet end 130. In this way, the upper edge 12 is first polished with a relatively large grinding angle, and gradually decreases as the upper edge 12 is moved toward the exit ends 130 of the wheels. As disclosed in US Pat. No. 3,461,616, the polishing operation performed at the polishing portion 18 forms a final honing or cutting edge face 52 (FIG. 5) on both sides of the cutting edge of the cutting surface 50. As shown in FIG. Cutting edge surface 52 is a convex surface in which the angle of the surface gradually decreases almost continuously as the distance from cutting edge 54 increases.

Representative, including the above-described abrasive parts 16 and 18, in the on-line face mass production inspection operation, the razor blade strip is transferred through the abrasive parts at a speed of about 160 ft / min. The wheels 20 and 22 are rotated at a speed of about 4500 rpm in both directions, and the wheels 120 and 122 are rotated at a speed of about 3600 rpm in both directions to contact the upper edge 12 downwardly from both sides. Typical average production speed is about 76,800 units per hour. Moreover, it continues to be produced at high production rates of highly uniform, high quality razor blades over an extended period of time without interrupting operation for equipment maintenance or adjustment, such as wheel replacement. The average continuous run time for a series of test runs is about 8 hours, but some test runs continue to run for 8 hours or more without disturbing the advanced razor blades.

Based on inspection operations, the present invention presents processes and apparatus that are relatively simple but much more efficient and very cost effective than conventional for high speed mass production of razor blades with a good combination of performance characteristics.

The above description of this invention relates to an embodiment in which the cutting surface 50 including the rough honing face 56 and the cutting edge face 52 is formed on both sides of the upper edge 12 of the strip 10. However, the present invention may also form a similar cutting surface in the lower edge portion 12a to provide a double edge razor blade. According to the present invention, two parallel-arranged interconnecting wheels, which are almost identical to the wheels 20 and 22 in the on-line inspection production operations for producing a double-edged razor blade, have the wheels 20 and 22 attached to the upper edge 12. It is arranged to be in abrasive relationship with the lower edge 12a in the same manner as described above before being aligned with. However, the planes of the wheel axes arranged to polish the lower edge 12a are opposite.

In other words, the lower edge portion 12a is subjected to almost the same grinding operation applied to the upper edge portion 12 by the wheels 20 and 22. However, the plane of the wheel axes for grinding the lower edge 12a is the plane of the wheels 24 and 24a of the wheels 20 and 22, as shown in the third and ten degrees. It is inclined upward toward the path of the lower edge portion 12a (that is, the plane 14) so as to achieve the same inclination angle obtained by inclining toward the path of. In on-line inspection production runs, two paralleled interconnecting wheels, which are approximately equal to the wheels 120 and 122 (FIG. 10), are provided with a polishing portion 18 to form a cutting edge face 52 at the lower edge 12a. Is located after the.

The wheels are arranged to have the same polishing relationship as the lower edge 12a as described for the wheels 120, 122. However, the axis plane of the wheels polishing the lower edge part 12a has the same inclination angle obtained by tilting the plane of the axis lines 124 upwardly away from the path of the upper edge part 12 as shown in FIG. It is inclined downward in the path plane of the lower edge part 12a so that it may achieve. In on-line inspection production runs, the average production rate of double-edged razor blades is about 36,000 per hour,

It will be clear from the foregoing description that the processes and apparatus of the present invention are superior and offer advantages beyond expectations. The combination of the reverse inclination angle and the ability of the polishing means to simultaneously polish the edges of the blade stock to gradually reduce the roughness and gradually increase the polishing angle, effectively combining the grinding and rough honing masking operations into a single operation. The use of spiral wheels allows metals to be removed completely and evenly. Moreover, spiral wheels provide a tighter nip that contributes to the faster removal of metal and higher blade speeds, which reduce the effects of wheel wear. These features, in cooperation with the reverse tilt angle and the polishing ability to provide very reliable and efficient polishing operations, alleviate the need for automatic control means currently used to monitor and control grinding and rough honing finishing operations. In addition, the polishing operation obtained with this invention is that a finer polishing operation removes more metal in one direction from the stream edge, while a finer polishing operation removes the metal little by little and is also directed to the edge. It is designed to be.

This polishing operation makes the removal of the metal very efficient and at a higher speed. Accordingly, the processes and apparatus of the present invention provide advantages over expectations over processes and apparatus known in the art at the time this invention is completed.

Claims (13)

Polishing the two sides with a set of paralleled wheels each having an axial length defining an inlet end and an outlet end, wherein the wheels are roughened as the two sides move from the inlet end to the outlet end. Is arranged to be suitable for simultaneously polishing the two sides so that the polishing angle is gradually decreased and the polishing angle is gradually increased, thereby forming a face at each opposite face that decreases the angle between both sides as the distance from the edge increases. A method of forming a surface on both sides terminated at the edge of the cutting mechanism. The method of claim 1, wherein the polishing angle at the inlet end is between about 10 ° -about 17 ° and the polishing angle gradually increases between about 14.5 ° -about 21.5 °. The method of claim 1, wherein the two-sided portions are polished with steric boron nitride. A method of forming a face on both sides of a blade material, comprising the following steps. a) parallelly disposed wheels rotatable about coplanar axes forming one plane, the axial length of each wheel having an inlet end, at the inlet end the wheels having relatively high roughness and thereafter Providing the wheels to gradually reduce roughness over a length. b) providing a path to move both sides of the blade material in abrasive relation with the wheels. c) arranging the plane and the path such that the plane and the path are at an inclined angle between the plane and the path, thereby relatively reducing the polishing angle at the inlet end and gradually increasing the polishing angle along the axial length of the wheels. d) rotating said wheels in opposite directions, and e) moving the two sides along the path to contact the rotating wheels so that the wheels are in polishing relation with the two sides along the axial length. 5. The method of claim 4, wherein the wheels are provided or equipped with a polishing surface consisting of steric boron nitride. 5. The method of claim 4 including grinding the both sides of the face to provide cutting edge facets on the both sides. 7. The method of claim 6, wherein the two sides are first polished to a relatively large polishing angle to form cutting edge facets with convex surfaces, and then the polishing angle is gradually reduced. a) two parallelly arranged abrasive wheels rotationally mounted about coplanar axes forming one plane, each of the wheels having an inlet end and an outlet end, wherein the inlet end has a relatively high roughness and the outlet end Polishing means comprising the polishing wheels that gradually reduce the roughness toward the side, and b) guide means for moving the both sides of the cutting mechanism along a path, wherein the guide means and the polishing means comprise the plane and the path. The plane and the path diverge past the polishing wheels along the moving direction of the cutting mechanism such that the wheels have a relatively small polishing angle at the inlet end and a polishing angle toward the outlet end. On both sides of the cutting mechanism, designed to gradually increase Apparatus for forming the surface. The device of claim 8, wherein the angle of inclination is between about 0.3 ° to about 10 °. The device of claim 8, wherein the wheels provide or have steric boron nitride. 9. An apparatus according to claim 8, comprising a second polishing means arranged to be suitable for grinding the both sides to form cutting edge facets on both sides of the face, the apparatus having an inlet end and an outlet end and having a second plane. And two abrasively disposed abrasive wheels rotatably mounted on parallel axes forming a circumference, wherein the abrasive wheels are arranged so as to form a predetermined inclination angle between the second plane and the path, each of which is A device for relatively increasing the polishing angle at the inlet end and gradually decreasing the polishing angle toward the outlet end. A razor blade comprising a cutting surface formed by two sides terminating at a cutting edge, each of the two sides comprising a rough honing face and a cutting edge face, wherein each rough honing face has an angle approximately in the direction of the cutting edge face. Razor blades with a substantially convex surface that continuously decreases gradually. 13. The razor blade of claim 12, wherein each cutting edge face has a convex surface, and the angle of the convex surface gradually decreases substantially continuously in the direction of the cutting edge.

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