CROSS REFERENCE TO RELATED APPLICATIONS

The present disclosure claims priority of U.S. provisional patent application No. 61/334,377 filed May 13, 2010, the entire contents of which are incorporated herein.

TECHNICAL FIELD

The present subject matter relates to shaving systems of a wet shave type, and in particular relates to blade supports in blade assemblies for the shaving systems. BACKGROUND

Some current conventional wet shaving systems feature razor cartridges that carry a plurality of razor blades in blade assemblies. Each blade assembly is formed by a razor blade being welded to a bent blade support. The blade assemblies each fit into respective slots at either end of a central opening of a razor cartridge housing. Some conventional razor cartridge housings ("cartridge housings") include springs such as cantilever or leaf-type spring fingers which bias the blade assemblies upward. A pair of metal clips is typically provided extending across the blades at respective opposing ends near the slots. The clips engage the underside of the cartridge housing to retain the blade assemblies in the cartridge housing. In certain designs, the slots and springs are arranged to allow the blades and blade supports to move under shaving forces, biased by the springs. In other designs, the springs are designed to allow movement during assembly only, to locate the blades to the surface of the blade retainers (or clips).

The cartridge housing also typically includes a soapbar or "guard" on a skin contacting surface in front of the blade opening, which can be made of an elastomeric material. The soapbar usually has a pattern of fins, pockets, or ridges for retaining a shaving aid and engaging the skin surface to induce tension. The cartridge housing further typically includes a lubricating strip behind the blade opening (and sometimes surrounding the blade opening) containing a water-leachable shaving aid.

The cartridge housing can also include a trimmer blade, for shaving sideburns and other hard-to-reach areas of the user's face. The edge of the trimmer blade typically extends parallel to the main shaving blades or approximately perpendicular to the main blades, and is located on the rear side of the cartridge housing, e.g., facing opposite the main shaving blades.

Blade supports for shaving razors fulfill several functions, such as: (i) providing a stable platform for the shaving razor blades, giving a reliably flat and properly angled blade assembly for optimum shaving performance; (ii) providing a means of positioning the blades within a razor cartridge housing incorporating other desirable attributes for shaving, and achieving control of shaving edges; (iii) allowing for a razor design with minimal restriction to flow of fluids around or between one or more blades, thus eliminating shaving debris; and (iv) providing a means for storage and transport of small blades during manufacture, preventing damage to the small blades, etc. While existing razors benefit from these functions provided by conventional blade support structures, there are a number of previously unaddressed problems. For example, conventional blade supports are fabricated from commonly used materials, possibly with edge treatments in an attempt to remove sharp edges by skiving or deburring, nevertheless retain residual "sharp" edges, corners, and burrs. These residual sharp features interfere with fluid flow between the blades, lead to inconsistency when attaching a blade to a blade support, and shed materials into precision assembly equipment possibly leading to damage and downtime. Further, these residual features obstruct insertion of the conventional blade support into precision fit, mating components made of plastic or other materials that can be deformed by these features, or require assembly clearance that would result in looseness at critical points.

As a result, there exists a need for blade supports without sharp edges, corners, etc. resulting in blade assemblies with functional advantages over conventional blade support designs.

SUMMARY

The teachings herein improve over conventional designs and provide designs of novel blade supports and methods for manufacturing the novel blade supports.

According to the present disclosure, the foregoing and other advantages are achieved in part by providing a blade support for a blade for a razor blade cartridge. The blade support includes an elongated body having two ends, wherein the elongated body is bent at an angle to form an upper blade attachment portion and a lower portion, and the blade support includes one or more bevels at its corners. The one or more bevels can be disposed at various corners of the blade support. For example, a first bevel can be disposed at a comer of the underside of the upper blade attachment; a second bevel can be disposed at an opposing comer of the end of the lower portion; and a third bevel can be disposed at a comer of the end of the lower portion, but on the same side as the first bevel.

In addition, in accord with another aspect of the disclosure, the blade support includes a radius at one or more comers of the elongated body. Further, the blade support can include a radius at each comer of the first bevel, second bevel, and/or third bevel.

In accord with another aspect of the disclosure, the elongated body of the blade support can include an indentation or channel near a bent portion of the elongated body in the underside of the upper blade attachment portion. Alternately, the elongated body of the blade support can be curved to wrap around and receive a blade support finger of the razor blade cartridge. Alternately, the blade support can include a blade mounted on the underside of the upper blade attachment portion of the elongated body, with a sharpened edge of the blade protruding beyond the end of the upper blade attachment portion.

In accord with another aspect of the disclosure, a method of manufacturing a blade support for a blade in a razor blade cartridge for a shaving system is provided. A wire having a cross section (e.g. circular) is shaped (via rolling or skiving operation) into a formed wire having a thickness and a substantially rectangular cross section. The formed wire is shaped into a precision shaped wire having a width and one or more bevels at comers. The precision shaped wire is bent at an angle to form the blade support including an upper blade attachment portion and a lower portion. The wire for blade supports can be made of carbon chrome nickel stainless steel. In more specific examples, materials having very low carbon are used. In accord with another aspect of the disclosure, the shaping in the method is performed so that the precision shaped wire includes a radius at each corner of the precision shaped wire. Further, the shaping is performed so that a first bevel of the one or more bevels can be disposed at a corner of the underside of the upper blade attachment; a second bevel can be disposed at an opposing corner of the end of the lower portion; and a third bevel can be disposed on the same side as the first bevel disposed at the corner of the underside of the upper blade attachment, but on the opposing side of the second bevel, at the end of the lower portion. The one or more bevels are shaped at a bevel angle between about 10 degrees and about 30 degrees.

In accord with another aspect of the disclosure, the rolling of the wire is performed so that the thickness of the formed wire is between about 0.07 mm and about 0.33 mm. Further, the shaping is performed so that the width of the precision shaped wire is between about 1.5 mm to about 4 mm. Furthermore, the shaping is performed so that the radius at each corner of the one or more bevels is between about 0.05 mm to a side-length divided by 2.

Additional advantages and novel features will be set forth in part in the description which follows and, in part, will become apparent to those having ordinary skill in the art upon examination of the following and the accompanying drawings or can be learned from production or operation of the examples. The advantages of the present teachings can be realized and attained by practice or use of the methodologies, instrumentalities and combinations particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference is made to the attached drawings, wherein elements having the same reference numeral designations represent like elements throughout, and wherein:

Figs. 1 and 2 illustrate cartridges utilizing the blade supports of the present disclosure.

Figs. 3 A and 3B illustrate some details of an example cartridge of Fig. 2.

Figs. 4 A and 4B illustrate a cartridge containing blade assemblies with blade supports according to the present disclosure.

Figs. 5 A and 5B illustrate a cross-sectional view of the cartridge of Fig. 4A showing blade assemblies in an enlarged view according to the present disclosure.

Fig. 6 illustrates a precision shaped wire before making a blade support according to the present disclosure.

Fig. 7 illustrates a blade assembly including a blade and a blade support according to the present disclosure.

Fig. 8 illustrates a blade assembly including a blade and another blade support according to the present disclosure.

Fig. 9 illustrates a blade assembly including a blade and a further example of a blade support according to the present disclosure.

Fig. 10 illustrates a blade assembly including a blade and a further example of a blade support according to the present disclosure. Fig. 11A illustrates a blade assembly including a blade and a further example of a blade support according to the present disclosure.

Fig. 1 IB is a partial front view of the blade assembly of Fig. 11A.

Fig. l lC illustrates a blade support including a guard portion according to the present disclosure.

Fig. 11D illustrates a blade support including a guard portion according to the present disclosure.

Fig. HE is a partial cross-sectional view of a guard portion shown in Figs. 11C, and 11D according to the present disclosure.

Fig. 1 IF is a partial cross-sectional view of a guard portion shown in Figs. 11C, and 11D according to the present disclosure.

Fig. 11G is a partial cross-sectional view of a guard portion shown in Figs. 11C, and 11D according to the present disclosure.

Fig. 12 illustrates a blade assembly including a blade and a further example of a blade support according to the present disclosure.

Fig. 13A illustrates a blade assembly including a blade and a further example of a blade support according to the present disclosure.

Fig. 13B illustrates a blade assembly including a blade and a further example of a blade support according to the present disclosure. DETAILED DESCRIPTION

A shaving cartridge using blade supports according to an embodiment of this disclosure will now be generally described with reference to Figs. 1-5. One example cartridge is a three-blade men's razor as shown in Fig. 1 and another is a five-blade women's razor as shown in Fig. 2. The cartridges shown in Figs. 1 and 2 are intended as merely examples and not exclusive or limiting in any way. Moreover, the features of one cartridge are intended to be usable by themselves or in combination with features of the disclosed blade supports.

Referring now to Figs. 3A and 3B, the men's and women's cartridge designs both include a housing 10 (also referred to as a "platform" herein) having a central blade opening 12 into which a plurality of blade assemblies (not shown) are inserted, where each blade assembly includes a blade attached to a blade support.

Fig. 3B shows that at either end of the central blade opening 12 are ribs 20 and springs 22 for supporting the blade assemblies in a desired orientation relative to the housing 10. The ribs 20 and springs 22 have substantially parallel opposing walls for orienting the blade assemblies. As shown in Figs. 4A and 4B, the springs 22 also support the blade assemblies from beneath the bent portions of the blade assemblies 24. Fig. 4B is a cross- sectional view of the cartridge of Fig. 4A illustrating a group of the blade assemblies 24a, 24b, 24c, 24d, and 24e.

As shown in Fig. 4A, the blade assemblies 24 are retained in the housing 10 by a pair of blade retainers 26 at respective ends of the central blade opening 12 of the housing 10, proximal the ribs 20. The blade retainers can be substantially U-shaped, with a central portion that extends across the blades, and a pair of legs that extend into cavities in the top of the housing 10. The legs form an interference fit with the cavities to retain the blade retainers 26 in the cavities. The springs 22 bias the blades against the retainers 26, thereby aligning the blade edges e.g. in a single plane defined by the underside of the central portion of the retainer. The elasticity of the springs 22 is such that the blades preferably do not move in response to shaving forces; that is, the blades remain in contact with the retainers during shaving.

Figs. 5A and 5B illustrate a cross-sectional view of the cartridge of Fig. 4A showing blade assemblies 24 according to the present disclosure. In Figs. 5A and 5B, the disclosed shaving system includes a cartridge including a housing 10, a plurality of blade assemblies (24a, 24b, 24c, 24d, and 24e) having blades (30a, 30b, 30c, 30d, and 30e) and blade supports (40a, 40b, 40c, 40d, and 40e). Here, each blade is attached to a blade support to form a blade assembly respectively. The blade can be attached to the support by welding, e.g. laser spot welding. For example, a blade assembly 24a includes a blade 30a attached to a blade support 40a, and a blade assembly 24b includes a blade 30b attached to a blade support 40b, etc. In addition, as shown in Fig. 5B, dl (the distance between one end of a blade and a sharpened cutting edge of an adjacent blade) is about 0.018 mm; d2 (the distance between one blade cutting edge to another blade edge) is about 0.048 mm; and d3 (the distance between a blade support and anther blade support) is about 0.038 mm. Fig. 6 illustrates a precision shaped wire for making a blade support according to the present disclosure. A method for manufacturing example blade supports according to the present teachings will now be described with reference to Fig. 6. First, a blade support material or a wire stock having a cross section is provided. The wire stock can be made of soft round wire, either 200/300 series stainless steel or other materials. In more specific examples, the wire stock is made of carbon chrome nickel stainless steel (SS), e.g., the wire stock is made from 300 series SS alloys (in the example, 304L to 316L alloys are used, "L" meaning very low carbon). By applying successive rolling (or skiving) operations to the wire stock in a known manner, a formed wire is formed without the burrs, corners, and sharp features of conventional processes, e.g. perforation or punching processes. Between successive rolling operations (or a number of rolling operations) the wire can be annealed to counteract any work hardening that might occur during a rolling operation. The formed wire has a thickness and a substantially rectangular cross section. After successive rolling (or skiving) operations, the formed wire is shaped into a precision shaped wire 100, as shown in Fig. 6, having one or more bevels or tapers (50 and 51). The one or more bevels 50, 51 provide a guiding feature for less sensitivity mating with other components, and increase the unrestricted opening between blades otherwise spaced apart by equal measure. In addition, those skilled in the art will appreciate that the above shaping, rolling, or forming step can include skiving, high pressure abrasion by either air or fluid mediums, laser or plasma material removal, abrasive shaping or electro-chemical shaping or burr removal, or any combinations thereof. The example precision shaped wire 100, as shown in Fig. 6, includes one or more bevels or tapers (50, 51), one or more radii (52a, 52b, 52c, 52d, 52e, and 52f) at corners, a thickness T, a bevel angle Θ, a width W, and a side-length J. The thickness T is in a range between about 0.07 mm and about 0.33 mm (for example, a thickness T is about 0.25 mm). The bevel angle Θ is in a range between about 10 degrees and about 60 degrees (for example, a bevel angel Θ is about 30 degrees). The width W of the precision shaped wire 100 is in a range between about 1.5 mm and about 4 mm (for example, a width W is about 2.67 mm). The side-length J is about 0.07 mm to 0.9 times the thickness T (for example, a side-length J is about 0.10 mm). The one or more radii (52a, 52b, 52c, 52d, 52e, and 52f) at the corners of the precision shaped wire 100 is in a range between about 0.05 mm to about a side-length J divided by 2 (for example, a radius is about 0.4 mm).

The precision shaped wire 100 is then formed into a final blade support by bending the precision shaped wire 100. For example, the precision shaped wire 100 is bent at an angle to form a blade support 200 having an upper blade attachment portion 72 and a lower portion 70, as shown in Fig. 7. The bending of the precision shaped wire 100 can be performed at an angle a by a coining bend which produces a sharp inside corner 76. The coining bend allows a reduction in the thickness t of the bent portion of the blade support 200, which further improves flow-through of liquid and shaving debris.

The exemplary blade support 200 provides significant improvements and benefits over conventional blade supports, as described below. First, a blade assembly including a blade attached to a blade support must fit the housing with a clearance such that they do not lead to inconsistent shave geometries, or blade "chatter" during shaving, that can cause cuts and nicks. This requires precision assembly equipment with virtually no allowable error. The one or more tapers or bevels of the example blade support 200 as described above and a lack of sharp features thereof allow assembly of blades to the housing 10 with a degree of tolerance. Furthermore, the most critical areas for fluid and debris to flow between blade assemblies are regions immediately behind the edges of the blades 30a-30e where hair cutting occurs. The tapered leading edge (or the edge of the bevel 50) of the blade support 200 and lack of sharp features greatly reduce the flow coefficient and potential for "catching" debris in the regions. Debris encounters a razor edge followed by smooth, streamline contours as opposed to blunt faces, burrs, or corners.

The exemplary blade support 200 provides other advantages as well. For example, the reduced frontal area of the tapered edges (or the bevel) 50, 51 of the blade support 200 (as impacting incoming debris and fluids) allows materials to be used for the blade support 200 with a larger nominal thickness than that of existing conventional blade supports, while still improving flow between blades. This stronger, more rigid support precludes any need for having additional supports or points of external reinforcement within the longitudinal blade span. Thus, flowing of fluids and debris is significantly improved by eliminating these blocking features otherwise required. Another advantage achieved by the exemplary blade support 200 is that the thicker blade support material described above also increases the inertial mass of the blade 30 during shaving. For example, as reducing unsprung weight in a vehicle suspension system makes the vehicle suspension system more responsive to outside forces, conversely increasing the blade mass at the very point of shaving increases the inertial mass of the blade 30 as it meets the resistance of a hair. This is a desirable feature because the blade impact is sustained through the cutting motion.

Referring now to Fig. 6, as previously discussed, the precision shaped wire 100 is made from a rolled wire stock with a substantially rectangular cross section, such as rolled and strip - annealed stainless steel wire. As shown in Fig. 6, the precision shaped wire 100 includes bevels such as 30 degree bevels 50, 51 at opposing corners. Alternately, the precision shaped wire 100 can include a single bevel. In addition, the precision shaped wire 100 has a radius at each corner or edge of the precision shaped wire 100. That is, there are no sharpened edges or burrs at each corner or edge of the precision shaped wire 100 so that a finished blade support 200 has rounded corners 52a - 52f as shown in Fig. 7. The rounded corners 52a-52f and bevels 50, 51 of the blade support 200 improve flow-through of water, soap, and other shaving debris away from the blades, thereby improving shaving performance and comfort during shaving operation.

Furthermore, the bevel 51 disposed at the bottom of the lower portion 70 ("the bottom bevel") and radii 52b-52d of the blade support 200 ease assembly operation of the cartridge by acting as a "lead in" for the blade support 200 when it is inserted into the cartridge. Thus, the disclosed blade support 200 enables faster, more reliable and less expensive cartridge assembly. Still further, the bevel 50 disposed on the upper blade attachment portion 72 ("the top bevel") of the blade support 200 advantageously allows the blade 30 to be supported closer to its cutting edge than it could be if the blade support 200 had a plain rectangular end. Support near the edge of the blade 30 results in additional shaving comfort.

As shown in Fig. 7, and previously discussed, the blade support 200 includes radii (52a-52f) at corners of the blade support 200 and bevels 50, 51 at opposing corners. Further, the blade support 200 is bent at an angle a using a coining bend, which produces a sharp inside corner 76. The coining bend allows a reduction into the thickness t of the blade support, which further improves flow-through of liquid and shaving debris. In the example, the bending angle a is between about 60 degrees and about 75 degrees (for example, a bending angle a is about 68 degrees); the length S is between about 0.25 mm and 1.50 mm (for example, a length S is about 0.75 mm); the length P is between about 0.075 mm to 1.0 mm (for example, a length P is about 0.28 mm); the blade width W _B is between about 0.30 mm and about 4 mm (for the example, a blade width W _B is about 1 mm); and the weld line W _L is about (W _B - P) divided by 2.

Fig. 8 illustrates a blade assembly including a blade and another exemplary blade support according to the present disclosure. The exemplary blade support 800 shown in Fig. 8 has a stamped indentation 880 near a bent portion in the underside of an upper blade attachment portion 872 of the blade support 800 to positively capture and locate a blade support finger 882 which are part of the springs 22 of the cartridge housing 10 (not shown in Fig. 8), for increased positional accuracy of the blade cutting edge e.g. in a fore and aft direction during shaving. The blade support finger 882 has a complementary shape to fit with the stamped indentation 880. Fig. 9 illustrates a blade assembly including a blade and a further example of a blade support according to the present disclosure. In another example, the blade support 900 shown in Fig. 9 includes a channel 984 disposed near a bent portion in the underside of the blade support 900 to capture and locate a complementary shaped blade support finger 986 to fit with the channel 984 to also provide the aforementioned positional accuracy benefits.

In still another example as shown in Fig. 10, the blade support 1000 is curved to wrap around and receive a blade support finger 1088 of the cartridge. The blade support 1000 includes a blade attachment portion 1072 to which a blade 30 is attached and a non -blade attachment portion 1070.

In another example, as shown in Fig. 11A and 1 IB, instead of a sharpened tip of the blade 30 extending well past the end of an upper blade attachment portion 1172 of the blade support 1100, a series of guard ribs 1190, similar to the "Virtual Guard" feature explained in U.S. Patent 6,378,211, is formed into the upper blade attachment portion 1172 extending toward the blade edge, as by stamping. Figs. 11 A and 1 IB illustrate that in this example, the blade edge is slightly behind the end of the upper blade attachment portion 1172 of the blade support 1100, and a series of guard ribs or protrusions 1190 extends upward from the front of the upper blade attachment portion 1172 of the blade support 1100 proximate the sharpened edge of the blade 30 such that a portion of the blade 30 adjacent the guard ribs 1190 has a negative exposure, thereby preventing cuts and abrasions to the skin. According to this example, the cartridge can have a separate Virtual Guard feature for every blade. Further, as shown in either FIG. 1 1C or FIG. 11D, the relationship between the blade edge and the virtual guard feature 1192a,b can be altered, either parallel or one extending past the other. The support or virtual guard attached to one blade can preferentially function as a guard for an adjacent blade. FIGS 1 lE-11G illustrate various forms and/or shapes of the guard portion 1192a,b in FIGS. 11C and 11D. FIG. HE shows the guard portion 1192a,b including a plurality of saw-tooth type protrusions 1194. FIG. HE shows the guard portion 1192a,b including a plurality of protrusions 1196, each protrusion spaced a predetermined distance apart from other protrusion. FIG. 11G shows the guard portion 1192a,b including a plurality of arc-shaped protrusions 1198.

In another example, as shown in Fig. 12, the blade 30 is mounted on the underside of an upper blade attachment portion 1272 of the blade support 1200, with the sharpened edge of the blade 30 protruding beyond the end of the upper blade attachment portion 1272 of the blade support 1200. The leading edge of the upper blade attachment portion 1272 of the blade support 1200 is rounded and the upper blade attachment portion 1272 can therefore act as a guard to increase shaving comfort.

In another example, as shown in Fig. 13 A, the blade support 1300 includes bevels 1350, 1351, and 1353. The bevel 1350 is disposed at a corner in the underside of the upper blade attachment portion 1372; the bevel 1351 is disposed at an opposing corner of the lower portion 1370 of the blade support 1300; and the bevel 1353 is disposed at an opposite side of the bevel 1351, but on the same side as the bevel 1350.

Also, in another example, as shown in Fig. 13B, the blade support 1400 includes bevels 1450, 1453 at corners on the same side of the blade support 1400. The bevel 1450 is disposed at a corner in the underside of the upper blade attachment portion 1472, and the bevel 1453 is disposed on the same side as the bevel 1450, at a corner of the lower portion 1470 of the blade support 1400.

The present disclosure can be practiced by employing conventional materials, methodologies and equipment. Accordingly, the details of such materials, equipment and methodologies are not set forth herein in detail. In the previous descriptions, numerous specific details are set forth, such as specific materials, structures, chemicals, processes, etc., in order to provide a thorough understanding of the present teachings. However, it should be recognized that the present teachings can be practiced without resorting to the details specifically set forth. In other instances, well known processing structures have not been described in detail, in order not to unnecessarily obscure aspects of the present teachings.

While the foregoing has described what are considered to be the best mode and/or other examples, it is understood that various modifications can be made therein and that the subject matter disclosed herein can be implemented in various forms and examples, and that the teachings can be applied in numerous applications, only some of which have been described herein. For instance, features disclosed in connection with any one embodiment can be used alone or in combination with each feature of the respective other embodiments. It is intended by the following claims to claim any and all applications, modifications and variations that fall within the true scope of the present teachings.