Abstract:
A handle for a shaving razor is described in which the handle comprises a grip portion and a neck portion coupled to an end of the grip portion. The neck portion comprises a frame coupled to the end of the grip portion, the frame comprising a pin; a pod rotatably coupled to the frame, the pod defining an aperture to receive the pin of the frame, wherein the pod is configured to rotate about an axis substantially perpendicular to a length of the grip portion; and a spring coupled to the pod, wherein the spring generates a return torque when the pod is rotated.

Description:
FIELD OF THE INVENTION 
     The invention generally relates to handles for razors, more particularly to handles with a rotatable portion such that a safety razor blade unit including at least one blade with a sharp cutting edge is mounted on the handle to be movable pivotally relative to the handle under forces exerted on the blade unit in the course of shaving. Such a blade unit of the safety razor can pivot about more than one axis of rotation. A blade unit may have a plurality of blades, for example two, three, four or more blades, with straight parallel cutting edges disposed for contact with the skin between guard and cap surfaces also provided on the blade unit. The guard may include a strip of elastomeric material with a surface configuration, for example upstanding projections such as in the shape of fins, to produce a desired interaction with the skin as the blade unit is moved across the skin in the performance of a shaving stroke. The cap surface may include a strip of material containing a shaving enhancement product, such as a lubricant, which can gradually leach out of the strip material for application to the skin during shaving. The safety razor blade unit may be mounted detachably on the razor handle to allow the blade unit to be replaced by a fresh blade unit when the blade sharpness has diminished to an unsatisfactory level. Alternatively, the blade unit can be connected permanently to the handle with the intention that the entire razor should be discarded when the blade or blades have become dulled. Detachable and replaceable blade units are commonly referred to as shaving cartridges. 
     BACKGROUND OF THE INVENTION 
     Recent advances in shaving razors, such as a 5-bladed or 6-bladed razor for wet shaving, may provide for closer, finer, and more comfortable shaving. One factor that may affect the closeness of the shave is the amount of contact for blades on a shaving surface. The larger the surface area that the blades contact then the closer the shave becomes. Current approaches to shaving largely comprise of razors with only a single axis of rotation, for example, about an axis substantially parallel to the blades and substantially perpendicular to the handle (i.e., front-and-back pivoting motion). The curvature of various shaving areas, however, does not simply conform to a single axis of rotation and, thus, a portion of the blades often disengage from the skin during shaving as they have limited ability to pivot about the single axis. Therefore, blades on such razors may only have limited surface contact with certain shaving areas, such as under the chin, around the jaw line, around the mouth, etc. 
     Razors with multiple axes of rotation may help in addressing closeness of shaving and in more closely following skin contours of a user. For example, a second axis of rotation for a razor can be an axis substantially perpendicular to the blades and substantially perpendicular to the handle, such as side-to-side pivoting motion. Examples of various approaches to shaving razors with multiple axes of rotation are described in U.S. Pat. Nos. 5,029,391; 5,093,991; 5,526,568; 5,560,106; 5,787,593; 5,953,824; 6,115,924; 6,381,857; 6,615,498; 6,880,253; and 7,913,393; U.S. Patent Application Publication Nos. 2009/066218; 2009/0313837; and 2010/0043242; and Japanese Patent Laid Open Publication Nos. H2-34193; H2-52694; and H4-22388. However, to provide another axis of rotation, such as an axis substantially perpendicular to the blades and substantially perpendicular to the handle; typically, additional parts are implemented with increased complexity and movement, but durability, performance, and efficiency may suffer over time. As a result, current approaches introduce complexities and durability issues for manufacturing, assembling, and using razors with multiple axes of rotation. 
     What is needed, then, is a razor, suitable for wet or dry shaving, with multiple axes of rotation, for example, an axis substantially perpendicular to the blades and substantially perpendicular to the handle and an axis substantially parallel to the blades and substantially perpendicular to the handle. The razor, including powered and manual razors, is preferably simpler, cost-effective, reliable, and durable. 
     SUMMARY OF THE INVENTION 
     In one aspect, the invention relates to a handle for a shaving razor. The handle comprises a grip portion and a neck portion coupled to an end of the grip portion. The neck portion comprises a frame coupled to the end of the grip portion, the frame comprising a pin; a pod rotatably coupled to the frame, the pod defining an aperture to receive the pin of the frame, wherein the pod is configured to rotate about an axis substantially perpendicular to a length of the grip portion; and a spring coupled to the pod, wherein the spring generates a return torque when the pod is rotated. 
     This aspect can include any one or more of the following features. The neck portion can further comprise an anchor coupled to the end of the grip portion and to the spring. The anchor can be made from metal, optionally, brass. The spring can be a tension spring. The pin can be made from metal, optionally, stainless steel. The spring can be adjustable to vary the spring force and the return torque. The neck portion can be configured to releasably engage a razor cartridge. The neck portion can further comprise a razor cartridge releasing assembly. The pod can define a recess to receive the razor cartridge releasing assembly. The pin of the frame can fall along the axis. The pod can be unitary and formed from molded plastic. The pod can rotate about 10 degrees to about 20 degrees from an at rest position, preferably about 15 degrees from the at rest position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the present invention, as well as the invention itself, can be more fully understood from the following description of the various embodiments, when read together with the accompanying drawings, in which: 
         FIG. 1  is a schematic perspective view of a shaving razor in accordance with an embodiment of the invention; 
         FIG. 2  is a schematic perspective view of a partial cross section of a handle of a shaving razor according to an embodiment of the invention; 
         FIG. 3  is a partial schematic side view of the partial cross section of the handle of  FIG. 2 ; and 
         FIG. 4  is a schematic exploded perspective view of the handle of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Except as otherwise noted, the articles “a,” “an,” and “the” mean “one or more.” 
     Referring to  FIG. 1 , a shaving razor  10  of the present invention comprises a handle  20  and a blade cartridge unit  30 , which may releasably attach or be permanently attached to the handle  20  and contains one or more blades. The handle  20  comprises a neck portion  21  and a grip portion  23 . The grip portion  23  comprises a frame  22 , a pod  24 , and a razor cartridge releasing assembly  26 . The pod  24  is operably coupled to the frame  22  such that the pod  24  is configured to rotate about an axis of rotation  28  that is substantially perpendicular to the blades and substantially perpendicular to a length of the handle  20 . The blade cartridge unit  30  is configured to rotate about an axis of rotation  32  that is substantially parallel to the blades and substantially perpendicular to the length of the handle  20 . Nonlimiting examples of suitable blade cartridge units are described in U.S. Pat. No. 7,168,173. When the blade cartridge unit  30  is attached to the handle  20 , the blade cartridge unit  30  is configured to rotate about multiple axes of rotation, for example, a first axis of rotation  28  and a second axis of rotation  32 . 
       FIGS. 2-4  depict an embodiment of a handle  40  of the present invention. The handle  40  comprises a grip portion  42  and a neck portion  44 . The neck portion  44  comprises a frame  46  and a pod  48  operably coupled thereto such that the pod  48  is configured to rotate about an axis of rotation  50  that is substantially perpendicular to a length of the handle  40 . Coupled to the pod  48  and the frame  46  includes a docking station  52  engageable with a blade cartridge unit (not shown) and an ejector button assembly  54  for releasing a blade cartridge unit from the handle  40 . Nonlimiting examples of suitable docking stations and ejector button assemblies are described in U.S. Pat. Nos. 7,168,173 and 7,690,122 and U.S. Patent Application Publication Nos. 2005/0198839, 2006/0162167, and 2007/0193042. In an embodiment, the docking station  52  and the ejector button assembly  54  are coupled to one another within a cavity of the pod  48 . 
     The frame  46  is coupled to a grip portion  42  of the handle  40  so as to provide a fixed reference for the pod  48 . The frame  46  can be received within the grip portion  42  by a snap fit, interference fit, screw thread connection, etc. A pin  56  of the frame  46  couples the pod  48  to the frame  46 . In an embodiment, the pin  56  is a component releasably attached to the frame  46 , e.g., via snap fit, interference fit, screw thread connection, etc. Alternatively, the pin  56  is integrally formed with the frame  46  such that the pod  48  can define apertures defined to receive the pin  56  via snap fit or interference fit. The apertures of the pod  48  correspond in shape and are configured to mate with portions of the pin  56 . In an embodiment, the pin  56  does not have a uniform shape. By way of example, the pin  56  may be generally cylindrical with one portion being of a larger cylindrical portion than another, smaller cylindrical portion. In such an example, the apertures of the pod  48  are similarly proportioned—with one aperture having a larger size than the other aperture—to receive the pin  56 . The pod  44  may, optionally, include a tail portion  58  extending therefrom. The tail portion  58  may be coupled to a spring  60  in which the spring  60  is coupled to an anchor  62 . The anchor  62  may be received within the grip portion  42  to anchor the tail portion  58  of the pod  48  within a cavity of the grip portion  42 . 
     In an embodiment, the pin  56  of the frame  46  lies along an axis of rotation  50  about which the pod  48  rotates. The spring  60  is attached to the tail portion  58  of the pod  48  in which rotation of the pod  48  from an at rest portion puts the spring  60  into tension—e.g., into further tension as the spring  60  may optionally be in tension when at rest—so that the spring  60  provides a torque to return the pod  48  to the at rest position. Additionally or alternatively, the spring  60  is adjustable to vary the spring force and the return torques. In an embodiment, the spring  60  is a tension spring or a coiled spring. An embodiment to adjust the spring  60  is to lengthen the spring  60  in the at rest position, e.g., a neutral position, preferably a neutral, preloaded position, when coupled to the tail portion  58 , by deepening the anchor  62  within the grip position  42 , to which the spring  60  is attached. The pod  48  is configured to rotate about 10 degrees to about 20 degrees from the at rest position, preferably about 15 degrees. In an embodiment, the pod  48  is unitary such that the tail portion  58  is integrally formed with the rest of the pod  48 . 
     In an embodiment, at least a portion of the frame  46 , pod  48 , and anchor  62  are made from hard plastic, such as Zylar®. Additionally or alternatively, one or more of the frame  46 , pod  48 , and anchor  62  are made from the same material. In an embodiment, the pin  56  of the frame  46  is made from hard plastic or metal (e.g., stainless steel). In an embodiment, the spring  60  is also made from plastic, such as hard plastic. Alternatively, the spring  60  is made from metal. 
     A further advantage of the present invention is that the strength of the return forces can easily be modified by using various spring elements, in which the spring elements are optionally adjustable. 
     For razors embodying the present invention the return force characteristic increases smoothly to a maximum with the effective spring rate of the return force characteristic gradually increasing as the pivot angle increases from the respective rest position. Furthermore, during the return pivotal movement the return force characteristic curve closely follows that relating to the pivotal movement in the opposite direction so that the return force is always consistent for a given pivotal displacement and smooth pivotal motion is achieved, such as if the blade unit undergoes reversals of pivoting direction in the execution of a shaving stroke. 
     It should be understood that every maximum numerical limitation given throughout this specification includes every lower numerical limitation, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this specification includes every higher numerical limitation, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this specification includes every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein. 
     The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm.” 
     Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern. 
     While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.