Abstract:
Replaceable shaving assemblies are disclosed that include a blade unit, a shell bearing element, and an interface element. The interface element is configured to removeably connect the shaving assembly to a handle, on which the blade unit is pivotably mounted. In some cases, a return element is integrally formed on the shell bearing unit between the blade unit and interface element. Shaving systems including such shaving assemblies are also disclosed, as are methods of using such shaving systems.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a continuation application of U.S. patent application Ser. No. 14/661,032, filed Mar. 18, 2015, which is a continuation application of PCT Application Serial No. PCT/US2013/052099, filed on Jul. 25, 2013 which claims priority of U.S. Provisional Application Ser. No. 61/706,533, filed on Sep. 27, 2012 and U.S. Provisional Application Ser. No. 61/706,537, filed on Sep. 27, 2012. The complete disclosure of each of these applications is hereby incorporated by reference herein. 
     
    
     BACKGROUND 
       [0002]    The invention relates to shaving systems having handles and replaceable blade units. Shaving systems often consist of a handle and a replaceable blade unit in which one or more blades are mounted in a plastic housing. After the blades in a blade unit have become dull from use, the blade unit is discarded, and replaced on the handle with a new blade unit. Such systems often include a pivoting attachment between the blade unit and handle, which includes a pusher and follower configured to provide resistance during shaving and return the blade unit to a “rest” position when it is not in contact with the user&#39;s skin. 
       SUMMARY 
       [0003]    In general, the present disclosure pertains to shaving systems and to replaceable shaving assemblies for use in such systems. The systems include a flexible return element, e.g., of an elastomeric material, which provides the resistance and return force that are often provided by a pusher and follower mechanism in prior art shaving systems. 
         [0004]    In one aspect, the invention features a replaceable shaving assembly that includes a blade unit comprising a plurality of longitudinally extending blades and defining an open rinsing area surrounding the blades, a shell bearing unit, mounted on a back surface of the blade unit, the shell bearing unit defining a pair of arcuate members disposed outside of the open rinsing area, and an interface element, configured to removeably connect the blade unit to a handle, on which the shell bearing unit is pivotably mounted. 
         [0005]    Some implementations include one or more of the following features. The shell bearing element may interact with the interface element. In some cases, arcuate members define articulating surfaces that are configured to enable pivoting of the blade unit with respect to the interface element. The shell bearing element may include a return element formed integrally with the shell bearing unit. The return element is configured to bias the blade unit towards a rest position with respect to a pivot axis that is generally parallel to a long axis of the blade unit. The return element is generally elastomeric, and may comprise a synthetic elastomer or natural rubber material. The return element may include an elongated member that extends longitudinally between the arcuate members, and in some cases may further include anchoring members that extend generally perpendicularly to the elongated member and are molded onto the arcuate members. The elongated member may include an opening configured to receive a protrusion extending from the handle interface element, e.g., a central, generally rectangular opening. 
         [0006]    In another aspect, the invention features a shaving system that includes a handle having a distal end and a proximal end, and, mounted on the handle, a shaving assembly that includes (a) a blade unit comprising a plurality of longitudinally extending blades and defining an open rinsing area surrounding the blades; (b) a shell bearing unit, mounted on a back surface of the blade unit, the shell bearing unit defining a pair of arcuate members disposed outside of the open rinsing area; and (c) an interface element configured to removeably connect the blade unit to the handle, on which the shell bearing unit is pivotably mounted. 
         [0007]    Some implementations of this aspect can include any one or more of the features discussed above with regard to the shaving assembly. 
         [0008]    In a further aspect, the invention features replaceable shaving assembly that includes a blade unit, a blade unit interface element mounted on the blade unit, and a handle interface element pivotably mounted on the blade unit interface element and configured to removably receive a handle. The blade unit interface element includes a return element configured to apply a return force to the handle interface element. 
         [0009]    Some implementations include one or more of the following features. The return force comprises a torsional force. The return element may be configured to bias the blade unit towards a rest position with respect to a pivot axis that is generally parallel to a long axis of the blade unit. The return element may be elastomeric, for example the return element may comprise a synthetic elastomer or natural rubber material. The return element may include an elongated member that extends generally parallel to the longitudinal axis of the blade unit, and in some cases may further include anchoring members that extend generally perpendicularly to the elongated member and are molded onto the arcuate members. The elongated member may include an opening configured to receive a protrusion extending from the handle interface element, e.g., a central, generally rectangular opening. In some cases, the blade unit interface element includes a pair of spaced, generally parallel arcuate members, and the elongated member extends between the arcuate members. 
         [0010]    In yet another aspect, the invention features a shaving system that includes a handle having a distal end and a proximal end, and mounted on the handle, a shaving assembly that includes a blade unit, a blade unit interface element mounted on the blade unit, and a handle interface element pivotably mounted on the blade unit interface element and configured to removably receive the handle. The blade unit interface element includes a return element configured to apply a return force to the handle interface element. 
         [0011]    Some implementations of this aspect can include any one or more of the features discussed above with regard to the shaving assembly. 
         [0012]    The invention also features methods of shaving. For example, in one aspect the invention features a method of shaving comprising contacting the skin with the blade unit of a shaving system comprising a handle having a distal end and a proximal end, and a replaceable shaving assembly comprising a blade unit, a blade unit interface element mounted on the blade unit, and a handle interface element pivotably mounted on the blade unit interface element and configured to removably receive a handle, wherein the blade unit interface element includes a return element configured to apply a return force to the handle interface element. As another example, the invention features a method of shaving comprising contacting the skin with the blade unit of a shaving system comprising a handle having a distal end and a proximal end, and a replaceable shaving assembly comprising a blade unit, a plurality of longitudinally extending blades and defining an open rinsing area surrounding the blades, a shell bearing unit, mounted on a back surface of the blade unit, the shell bearing unit defining a pair of arcuate members disposed outside of the open rinsing area, and a return element disposed between the blade unit and interface element and an interface element configured to removeably connect the blade unit to a handle, on which the shell bearing unit is pivotably mounted. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective view of an assembled shaving system according to one embodiment. 
           [0014]      FIG. 2  is a perspective view of the shaving assembly portion of the shaving system. 
           [0015]      FIG. 3  is an exploded view of the shaving assembly. 
           [0016]      FIG. 4  is a side plan view of the shaving assembly. 
           [0017]      FIG. 5  is a rear plan view of the shaving system. 
           [0018]      FIG. 6  is a plan view of the shell bearing unit with the return element and blade unit. 
           [0019]      FIGS. 7-7B  are perspective views showing a shell bearing assembly and return element according to an alternate embodiment. In  FIG. 7A  part of the return element is cut away to show the underlying area of the shell bearing assembly, and in  FIG. 7  the guard is omitted whereas in  FIG. 7B  it is included. 
           [0020]      FIG. 8  is a series of diagrammatic views illustrating how the angle of the blade unit with respect to the handle is measured. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    The present disclosure relates generally to consumer products and, in particular, to shaving systems with interchangeable blade units. In one embodiment, the present disclosure features a reusable consumer product system having an interchangeable pivoting blade unit. 
         [0022]    Referring to  FIG. 1 , a shaving system  10  includes a handle  12 , an interface element  14 , a return element  16 , a shell bearing unit  18 , and a blade unit  20 , which includes a plurality of blades  22 . Referring to  FIG. 8 , the angle of blade unit  20  with respect to handle  12  can range from approximately 15° to 105°. The handle  12  provides a manner in which the shaving system can be manipulated and leverage can be applied to achieve desired shaving results. 
         [0023]    Referring to  FIG. 2 , a shaving assembly  5  comprises the blade unit  20 , shell bearing unit  18 , and interface element  14 . This shaving assembly would be sold to the user as a complete, replaceable unit. The interface element  14  has a handle interface portion  50  that allows the shaving assembly to be removably attached to the handle  12  ( FIG. 1 ). This could be accomplished in a number of manners, such as a mechanical locking mechanism, magnetic interaction, etc. For example, the handle interface element  14  and handle  12  can interface in the manner discussed in U.S. Ser. No. 61/651,732, filed May 25, 2012, the full disclosure of which is incorporated herein by reference. 
         [0024]    The shell bearing unit  18  includes arcuate members that define two articulating “shell bearing” surfaces  35 A and  35 B that are configured to interact with two complimentary surfaces  25 A and  25 B of the interface element  14 . This interaction allows controlled pivoting articulation of the blade unit  20  to occur. Pivoting of the blade unit  20  is about an axis that is generally parallel to the long axis of the blade unit and is generally positioned to allow the blade unit to follow the contours of a user&#39;s skin during shaving. 
         [0025]    Referring to  FIGS. 2 and 4 , the interface element  14  includes clip members  11 A,  11 B that are configured to grasp the outer edges of the articulating surfaces  35 A and  35 B of the shell bearing unit  18  to effectively hold the shell bearing unit  18  together with the interface element  14 . 
         [0026]    Referring to  FIGS. 1, 2, 3 and 5 , the shell bearing articulating surfaces  35 A and  35 B are positioned to align with the areas  21 A,  21 B ( FIG. 3 ) of the blade unit  20  that are outboard of the area of blades  22  that is exposed for rinsing. These areas  21 A,  21 B are generally where clips ( FIG. 3 ) are positioned to hold the blades in place. This configuration of the articulating surfaces  35 A and  35 B of the shell bearing unit  18  allows debris (e.g., hair) passing between the blades  22  in the rinsing areas  23 A- 23 C ( FIG. 3 ) to exit the blade unit  20 , resulting in less accumulation, increased rinsability and improved ease of cleaning. 
         [0027]    Referring to  FIG. 3 , the blade unit  20  is mounted on shell bearing unit  18  by the positioning of a pair of fingers  30  which extend from the shell bearing unit  18  into receiving bores  24  on the blade unit  20 . The receiving bores  24  may be molded integrally with the blade unit  20 . In addition, the shell bearing unit  18  includes tabs  40 A and  40 B that are received by bores  52 A and  52 B ( FIG. 3 ) on the blade unit  20  and serve as lateral attachment points for the blade unit  20 . 
         [0028]    Referring to  FIGS. 1-3 and 6 , a return element  16  extends longitudinally between the two arcuate members of the shell bearing unit  18 . The return element  16  may be integrally molded with the shell bearing unit  18 , e.g., by co-molding. It is noted that the term “co-molding,” as used herein, includes transfer molding and other techniques suitable for molding two or more different materials into a single part. 
         [0029]    The return element  16  includes an opening  48  that is configured to receive a protrusion  27  that extends from the interface element  14  as shown, e.g., in  FIG. 2 . Preferably, opening  48  is in the center of the return element as shown. The interaction of the protrusion  27  and return element  16  provides resistance during shaving, limiting the free pivoting of the blade unit about the pivot axis described above, and provides a torsional return force that biases the blade unit towards its rest position, in the same manner that resistance and return are typically provided by a pusher/follower assembly. No torque is applied at rest, but as soon as a force is applied to the blade unit a torsional load is generated on the return element. In some implementations, the return element is designed so that its geometry provides a force of up to 50 grams, e.g., from about 5 to 50 grams or about 10 to 40 grams. 
         [0030]    As shown in  FIGS. 7-7B , in some implementations the return element  16  includes a pair of anchoring portions  116 A,  116 B, that extend generally perpendicularly to the longitudinally extending portion of the return element  16  and are molded onto recessed areas  118  ( FIG. 7A ) of the shell bearing member. 
         [0031]    In an alternate embodiment (not shown), a portion of the return element  16  is reinforced with a hard plastic or another stiffening element, so that the movement of the return element  16  is primarily rotational and lateral deflection is minimized. 
         [0032]    The return element  16  can be formed, for example, from synthetic or natural rubber materials. Preferably, the return element is formed from the same material as the guard. Suitable materials are well known in the shaving system art, and include, for example, polyether-based thermoplastic elastomers (TPEs) available from Kraiburg HTP, thermoplastic urethanes (TPUs), silicones, and polyether-based thermoplastic vulcanizate elastomer (TPVs) available from GLS PolyOne Corporation under the tradename Santoprene™. The elastomeric material is selected to provide a desired degree of restoring force and durability. In some implementations, the elastomer has a Durometer of less than about 45 Shore A, e.g., from about 20 to 90 Shore A. 
         [0033]    A number of embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. 
         [0034]    For example, while the shell bearings have been shown as positioned entirely outboard of the rinsing areas, a small amount of the rinsing areas can be obstructed if necessary, e.g. less than 10%, preferably less than 5%, and more preferably less than 1% of the total rinsing area. 
         [0035]    Accordingly, other embodiments are within the scope of the following claims.