Abstract:
A shaving system comprising a razor handle having a razor cartridge pivotally connected thereto, the normal shaving process causing the razor cartridge to be pivoted to a first, upwardly pivoted, position and a second, downwardly pivoted, position, the razor handle comprising flexible spring fingers extending toward each other having cam followers for engaging a cam surface on an underside of the razor cartridge, the cam followers providing a biasing force on the cam surface such that the pivoted cartridge is returned to a neutral position.

Description:
RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/373,318 entitled “Razor Handle With Cantilevered Spring Fingers” invented by Frank Prochaska filed, Apr. 18, 2002, which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a shaving system. The present invention has particular applicability to razor handle and cartridge configured to permit pivotal rotation of a razor cartridge utilizing spring fingers to return the cartridge from a pivoted position to a neutral position. 
     BACKGROUND ART 
     Many conventional shaving razor handle heads are configured to permit rotation of a razor cartridge about a pivot point. Some arrangements permit free rotation of the razor cartridge through a predetermined range about pins attached to the head and engaging an underside of the razor cartridge. Other types include arcuate bearings formed in the handle head, which mate with hooks on the underside of the razor cartridge. The arcuate bearings determine the range of pivoting motion of the cartridge. Some handle heads spring-load or bias the pivotally mounted razor cartridge toward a neutral position, such as at or near the midpoint of the predetermined range, allowing the cartridge to be displaced away from the neutral position in one direction, and to then move back to the neutral position using complicated spring configurations or requiring unique or specialized razor cartridges. Thus, there is a need for a simplified, inexpensive razor cartridge biasing device that can be used with a conventional razor cartridge. 
     SUMMARY OF THE INVENTION 
     The present invention uses spring fingers to bias a pivoted razor cartridge back to a neutral position. The spring fingers, which have cam followers on each end, extend from the arms of the razor handle towards the middle of the handle to contact a cam surface of the cartridge. The spring fingers are molded integrally with the handle. Since they are separate from each other, they do not interfere with one another in operation. 
     According to the present invention, the foregoing and other advantages are achieved in part by a razor cartridge biasing device for a razor handle, comprising a razor handle having a pair of opposing arms extending from the handle head, distal portions of the arms comprising connectors to which a razor cartridge can be pivoltally connected; a first spring finger extending from one of the arms towards the other arm; a second spring finger extending from the other arm toward the first spring finger; each spring finger having a cam follower attached. One cam follower engages one portion of a cam located on the razor cartridge when the cartridge is pivoted in the upward direction during the normal course of shaving, thus urging the cartridge back to a neutral position. The other cam follower engages another portion of the same cam when it is pivoted in the downward direction, thus urging it back to the same neutral position. 
     Additional advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description, wherein only the preferred embodiment of the present invention is shown and described, simply by way of illustration of the best mode contemplated for carrying out the present invention. As will be realized, the present invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive. 
    
    
     
       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: 
         FIG. 1  is a perspective view of a razor handle having spring fingers in accord with the invention. 
         FIG. 2  is a side view of a razor handle having spring fingers in accord with the invention. 
         FIG. 3  is a top view of a razor handle having spring fingers in accord with the invention. 
         FIG. 4  is a bottom view of a razor handle having spring fingers in accord with the invention. 
         FIG. 5A  is a perspective view of a shaving system having spring fingers in accord with the invention with the cartridge in the first, upwardly pivoted, position. 
         FIG. 5B  is a enlarged partial view of a shaving system having spring fingers in accord with the invention as shown in  FIG. 5A . 
         FIG. 6A  is a perspective view of a shaving system having spring fingers in accord with the invention with the cartridge in the neutral position. 
         FIG. 6B  is a enlarged partial view of a shaving system having spring fingers in accord with the invention as shown in  FIG. 6A . 
         FIG. 7A  is a perspective view of a shaving system having spring fingers in accord with the invention with the cartridge in the second, downwardly pivoted, position. 
         FIG. 7B  is a enlarged partial view of a shaving system having spring fingers in accord with the invention as shown in  FIG. 7A . 
         FIG. 8A  is a rear view of a shaving system having spring fingers in accord with the invention. 
         FIG. 8B  is a cross-sectional view of a shaving system having spring fingers in accord with the invention taken through line  8 B— 8 B of  FIG. 7B . 
     
    
    
     DESCRIPTION OF THE INVENTION 
     In accord with the present invention, a razor handle is integrated with spring fingers which bias an attached razor cartridge toward a neutral position from either a first, upwardly pivoted, position, or a second, downwardly pivoted, position. In a one embodiment, the spring fingers of the present invention are angled to provide centering of the cartridge (i.e., displacement toward a neutral position) by imparting upon the razor cartridge a multi-dimensional force component (i.e., a direction that is not exclusively along a normal direction to the arcuate rails), thereby increasing the friction in the pivot. 
     As shown in one embodiment in  FIGS. 1–4 , razor handle  10  is provided with two outwardly protruding arms  10   a  and  10   b . Arms  10   a  and  10   b  include connectors  20   a  and  20   b , respectively, to which underside  75   b  of razor cartridge  75  may be connected. As illustrated, arms  10   a  and  10   b  also comprise retention collars  13   a  and  13   b , respectively, on which corresponding surfaces of underside  75   b  of razor cartridge  75  may slide. Spring fingers  40   a  and  40   b  extend inwardly toward longitudinal center line  45  from arms  10   a  and  10   b , respectively, (see  FIG. 4 ). 
     Spring fingers  40   a  and  40   b  extend away from arms  10   a  and  10   b , respectively. In this embodiment, spring fingers  40   a  and  40   b  are slightly angled, (best shown in  FIGS. 3 and 4 ) and are formed as integral parts of arms  10   a  and  10   b . Alternatively, spring fingers  40   a  and  40   b  may be added as separate components during the manufacturing process. As shown in  FIGS. 1 ,  3 , and  4 , spring fingers  40   a  and  40   b  are splayed from one another and are not coaxial. 
     Spring fingers  40   a  and  40   b  also include spring finger heads  50   a  and  50   b , respectively, and are disposed at a distal end of each spring finger  40   a  and  40   b . Spring finger heads  50   a  and  50   b  are generally box-like (e.g., about 0.040″×0.040″×0.050″), and possess a slightly angled or curved surface (e.g., 0.0150″ radius) on a face opposing a position to be ultimate occupied by a corresponding cam surface on underside  75   b  of razor cartridge  75 . Those skilled in the art would appreciate that the shape of spring finger heads  50   a  and  50   b  is not limited to a box, but can be any shape that would maximize the biasing force on cam surfaces  70   a  and  70   b  as described later herein. Spring finger heads  50   a  and  50   b  are positioned to straddle center line  45  of razor handle  10  along longitudinal axis  45  as shown in  FIG. 4 . 
     Razor handle  10  also includes arms  10   a  and  10  that include connectors  20   a  and  20   b , respectively, as shown generally in  FIGS. 1–4  and in detail in  FIGS. 5A–7B . Connectors  20   a  and  20   b  are identical in construction. Connectors  20   a  and  20   b  include retention collars  13   a  and  13   b  having rear surfaces  11   a  and  11   b  and front surfaces  14   a  and  14   b , best shown in  FIGS. 5A–7B . Connectors  20   a  and  20   b  are formed as integral parts of arms  10   a  and  10   b . Retention collars  13   a  and  13   b  are bounded by upper mechanical stops  12   a  and  12   b  and lower mechanical stops  15   a  and  15   b . For connector  20   a , rear surface  11   a , upper mechanical stop  12   a , and lower mechanical stop  15   a  combine to form a closed path to allow retention hook  78   a  to travel therein as described in further detail below. Similarly, for connector  20   b , rear surface  11   b , upper mechanical stop  12   b , and lower mechanical stop  15   b  combine to form a closed path to allow retention hook  78   b  to travel therein as further described below. 
     The shaving system of the present invention includes razor cartridge  75  having a topside  75   a  and an underside  75   b . Topside  75   a  is a conventional razor cartridge design which includes such standard features as soap bar  84 , razor blades  86 , and guard member  88 . Underside  75   b  includes cam  71 , retention struts  76   a  and  76   b , and pivot ridges  77   a  and  77   b.    
     Cartridge  75  includes cam  71 , best shown in  FIGS. 5A–7B . Cam  71  is located at the center of the length of cartridge  75  and spans at least a portion of the width of underside  75   b  of cartridge  75 . Cam  71  includes lower portion  71   a , center portion  71   b , and upper portion  71   c . Center portion  71   b  of cam  71  is of reduced thickness with respect to lower and upper portions  71   a  and  71   b , shown best in  FIGS. 5B ,  6 B, and  7 B. While shown as a “V” configuration in  FIG. 5B , cam  71  can be a convex or other configuration, best designed to provide a biasing force when used with cam followers, previously described as spring finger heads  50   a  and  50   b . Cam  71  also includes cam surfaces  70   a  and  70   b  that correspond to lower and upper cam portions  71   a  and  71   b . In one embodiment, cam  71  is a “V” configuration having vertex  80 . In such a configuration cam surfaces  70   a  and  70   b  are flat. However, in an alternate embodiment (not shown), cam  71  may be a convex configuration, among others, making cam surfaces  70   a  and  70   b  curved and eliminating vertex  80  altogether. 
     Cartridge  75  also includes pivot ridges  77   a  and  77   b , shown in  FIGS. 5A ,  6 B, and  7 B, but best shown in  FIG. 8B . Pivot ridges  77   a  and  77   b  are convex surfaces are located on underside  75   b  of cartridge  75  and in one embodiment of the present invention preferably are positioned such that they approximately divide the length of cartridge  75  into thirds. Pivot ridges  77   a  and  77   b  are illustrated as being formed as an integral part of cartridge  75  but in the alternative may be added separately during the assembly process and may be made of any suitable material. Pivot ridges  77   a  and  77   b  generally span the width of underside  75   b  of cartridge  75  as shown in  FIGS. 5A–7B . 
     Razor cartridge  75  also includes retention struts  76   a  and  76   b  that extend away from and generally perpendicular to underside  76   b  of cartridge  75 , best shown in  FIGS. 5A–7B . Retention struts  76   a  and  76   b  are located along the length of cartridge  75  closer to the ends than are pivot ridges  77   a  and  77   b . The exact spacing is a chosen such that retention struts  76   a  and  76   b  cooperate with connectors  20  located on razor handle  10 , the operation of which is discussed in detail below. Retention struts  76   a  and  76   b  are formed as an integral part of cartridge  75  according to one embodiment of the invention but in the alternative can be added separately during the assembly process and may be made of any suitable material. Formed on retention struts  76   a  and  76   b  are retention hooks  78   a  and  78   b , respectively. Retention hooks  78   a  and  78   b  are projections formed back towards underside  75   b  of cartridge  75  at an angle resembling a “check mark” or hook when viewed along the plane of cartridge  75 , best shown in  FIGS. 5A–7B . Retention strut  76   a , retention hook  78   a , and pivot ridge  77   a  combine to define retention slot  14   a  on one end of cartridge  75 . Similarly, retention strut  76   b , retention hook  78   b , and pivot ridge  77   b  combine to define retention slot  14   b  on the other end of cartridge  75 . 
     The present invention includes a shaving system having cartridge  75  with the ability to pivot through a range of motion from a first, upwardly pivoted, position, shown in  FIG. 5A , through a second, neutral position, shown in  FIG. 6A , to a third, downwardly pivoted, position, shown in  FIG. 7A . Of course, the first and third positions represent the extreme pivoted positions; cartridge  75  may pivot up or down to a lesser extent as the cartridge conforms to the contours of the user&#39;s face during the shaving process. 
       FIGS. 5A and 5B  depict razor cartridge  75  in the first, upwardly pivoted, position. Forces during the normal course of shaving, such as the contours of the user&#39;s face, may cause cartridge  75  to pivot in the upward direction. Cartridge  75  pivots on handle  10  on several of its surfaces. Pivot ridges  77   a  and  77   b  of cartridge  75  slidably engage front surfaces  14   a  and  14   b  of retention collars  13   a  and  13   b , respectively, best shown in  FIG. 5B . Furthermore, retention hook  78   a  rides against rear surface  11   a  of retention collar  13   a  and the corresponding retention hook (not shown) engages the corresponding rear surface (not shown) for retention collar  13   b . As cartridge  75  pivots upward, the travel of retention hook  78   a  is limited by lower mechanical stop  15   a . Similarly, the travel of retention hook  78   b  is limited by lower mechanical stop  15   b . Also, retention collar  13   a  engages slot  79   a  on one side of handle  10 , as does the corresponding rail (not shown) engage the corresponding slot on arm  10   b  on the other side of handle  10 . As cartridge  75  pivots upward, spring heads  50   a  and  50   b  contact respective cam surfaces  70   a  and  70   b  of razor cartridge  75 . In the exemplary embodiment of the present invention, cam surfaces  70   a  and  70   b  are different surfaces of cam  71  and are oppositely inclined about center point  80 , shown in  FIG. 5B . 
     When the forces on shaving cartridge  75 , such as the current contours of the user&#39;s face, are relieved, spring finger head  50   b  acts as a cam follower with respect to cam portion  70   b  and exerts a biasing force thereon, thus urging cartridge  75  back to a neutral position, as shown in  FIGS. 6A and 6B . 
       FIGS. 6A and 6B  show cartridge  75  in the second, neutral, position. Spring finger heads  50   a  and  50   b  either do not contact respective cam surfaces  70   a  and  70   b  or do not exert any appreciable centering force thereon. Thus, near the neutral position, centering forces are negligible. 
       FIGS. 7A and 7B  depict cartridge  75  in the third, downwardly pivoted, position. Forces similar to those that cause cartridge  75  to pivot in the upward direction, previously described, may also cause cartridge  75  to pivot in the downward direction. As such, the pivoting mechanism of cartridge  75  with respect to handle  10  is the same. Pivot ridges  77   a  and  77   b  of cartridge  75  slidably engage front surfaces  14   a  and  14   b  of retention collars  13   a  and  13   b , respectively, best shown in  FIG. 7B . Furthermore, retention hook  78   a  rides against rear surface  11   a  of retention collar  13   a  and the corresponding retention hook (not shown) engages the corresponding rear surface (not shown) for retention collar  13   b . As cartridge  75  pivots downward, the travel of retention hook  78   a  is limited by upper mechanical stop  12   a . Similarly, the travel of retention hook  78   b  is limited by upper mechanical stop  12   b . Also, retention collar  13   a  engages slot  79   a  on one side of handle  10 , as does the corresponding rail (not shown) engage the corresponding slot  79   b  on arm  10   b  on the other side of handle  10 . As cartridge  75  pivots downward, spring head  50   a  contacts cam surface  70   a  of razor cartridge  75 . In the embodiment depicted, cam surfaces  70   a  and  70   b  are different surfaces of cam  71  and are oppositely inclined about center point  80 , shown in  FIG. 5B . 
     When the forces on shaving cartridge  75 , such as the current contours of the user&#39;s face, are relieved, spring finger head  50   a  acts as a cam follower with respect to cam portion  70   a  and exerts a biasing force thereon, thus urging cartridge  75  back to a neutral position, as shown in  FIGS. 7A and 7B . 
     Additional advantages of the present invention will become readily apparent to those skilled in this art from the detailed description herein, wherein only exemplary embodiments of the present invention are shown and described by way of illustration of the best mode or modes contemplated for carrying out the present invention. As will be realized, the present invention is capable of other and different embodiments, and its details are capable of modifications in various obvious respects, all without departing from the concept of the disclosed invention. Accordingly, the drawings and description are to be regarded as merely illustrative in nature, and are not to be regarded as limiting or restrictive on the broad aspects of the invention provided herein.