Abstract:
A razor cartridge is provided including a blade unit having a first side wall, a second side wall, and a pair of end walls interconnecting the first side wall and the second side wall and one or both of the side walls of the blade unit having at least one connection member. A plurality of blades secured to the blade unit with a clip positioned at each end of the blade unit adjacent to the end walls. A frame is provided having a first interior wall and a second interior wall spaced apart from first interior wall that define an opening extending completely through the frame. One or more of the interior walls of the frame include at least one connection member, the latter engaged with the at least one connection member of the blade unit so that the frame is secured to the blade unit.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a Continuation of U.S. application Ser. No. 11/788,672, filed on Apr. 20, 2007. 
    
    
     FIELD OF THE INVENTION 
     The present invention is directed to a razor cartridge and more particularly to a razor cartridge constructed of a blade unit and a frame secured to the blade unit. 
     BACKGROUND OF THE INVENTION 
     Razor cartridges are designed to cut or shave a user&#39;s hair. The cartridges include one or more blades having at least one sharpened edge. The blades are held in place by what is commonly referred to as a housing. The housing typically includes one or more features to improve the overall shaving experience. Such common features include a guard which is located on the housing in front of the blades and a cap which is located behind the blades. The guard often includes an elastomeric member and the cap often includes a lubricating strip of some kind. 
     On the market today are a vast number of razor cartridge configurations. Some have big guards, some have smaller guards, some guards have elastomeric members with fins while others have elastomeric members with depressions and some guards have lubricating strips. Similarly some razor cartridges have big caps, some have smaller caps, and some caps have a lubricating strip. 
     In order to meet the demands of consumers, numerous designs have been configured. The numerous designs come at a cost however as much effort is spent on each design. That is, each cartridge is designed from scratch such that none of the molds and production equipment used to make one cartridge can be utilized to make a cartridge of a different design. For example, the molds and production equipment used to make the Gillette™ Mach3™ razor cartridge could not be used to make the Gillette™ Fusion™ razor cartridge. This results in higher cost as product design, molding and production equipment has to be executed separately for each product. Thus, there is a need for an alternative design to reduce cost and effort to produce different razor cartridges to meet the demands of consumers. 
     Ideally, one would like to start with a standard blade unit that houses the blades. One could then have the flexibility to add frames of various configurations to the standard blade unit. To keep the blade unit in its simplest form the pivot portion of the cartridge should be part of the frame and not part of the blade unit. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention a razor cartridge for connecting to a handle is provided. The razor cartridge comprises a blade unit comprising a plurality of shaving blades. The shaving blades extend along respective parallel blade axes. The shaving blades comprise sharpened edges. The sharpened edges define a blade plane. A frame is secured to the blade unit. The frame has a frame perimeter, an upper surface and a pivoting structure. The frame perimeter defines a razor cartridge perimeter for the razor cartridge. The pivoting structure defines a pivot axis for pivoting the razor cartridge with respect to the handle. The pivot axis is positioned within the frame such that a line drawn through the pivot axis perpendicular to the blade plane intersects the upper surface of the frame at a pivot frame intersection location where a tangent line drawn along the upper surface at the pivot frame intersection location is parallel to the blade plane. A first planar surface on the upper surface is located in front of the pivot frame intersection location and a second planar surface on the upper surface is located behind the pivot frame intersection location. The first planar surface is coplanar with the second planar surface. 
     In accordance with another aspect of the present invention a razor cartridge for connecting to a handle is provided. The razor cartridge comprises a blade unit comprising a plurality of shaving blades. The shaving blades extend along respective parallel blade axes. The shaving blades comprise sharpened edges. The sharpened edges define a blade plane. A frame is secured to the blade unit. The frame has a frame perimeter, an upper surface and a pivoting structure. The frame perimeter defines a razor cartridge perimeter for the razor cartridge. The pivoting structure defines a pivot axis for pivoting the razor cartridge with respect to the handle. The pivot axis is positioned within the frame between the upper surface and the lower surface such that a line drawn through the pivot axis perpendicular to the blade plane intersects the upper surface of the frame at a pivot frame intersection location where a tangent line drawn along the upper surface at the pivot frame intersection location is parallel to the blade plane. A first planar surface on the upper surface is located in front of the pivot frame intersection location and a second planar surface on the upper surface is located behind the pivot frame intersection location. The first planar surface is coplanar with the second planar surface. 
     In accordance with another aspect of the present invention a razor cartridge for connecting to a handle is provided. The razor cartridge comprises a blade unit comprising a plurality of shaving blades secured to the blade unit. The shaving blades extend along respective parallel blade axes. The shaving blades comprise sharpened edges. The sharpened edges define a blade plane. A frame is secured to the blade unit. The frame has a frame perimeter, an upper surface and a pivoting structure. The frame perimeter defines a razor cartridge perimeter for the razor cartridge. The pivoting structure defines a pivot axis for pivoting the razor cartridge with respect to the handle. The pivot axis is positioned within the frame between the upper surface and the lower surface such that a line drawn through the pivot axis perpendicular to the blade plane intersects the upper surface of the frame at a pivot frame intersection location where a tangent line drawn along the upper surface at the pivot frame intersection location is parallel to the blade plane. A first planar surface on the upper surface is located in front of the pivot frame intersection location and a second planar surface on the upper surface is located behind the pivot frame intersection location. The first planar surface is coplanar with the second planar surface. 
     In accordance with the present invention the pivot axis may be located in front of the blade axes or in back of the blade axes. 
     In accordance with the present invention the blade unit comprises a first shaving blade and a last shaving blade, said first shaving blade extends along a first blade axis and the last shaving blade extends along a last blade axis. The pivot axis may be located in between the first blade axis and the last blade axis, at the first blade axis or at the last blade axis. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as forming the present invention, it is believed that the invention will be better understood from the following description taken in conjunction with the accompanying drawings. 
         FIG. 1  is a top plan view of a razor cartridge of the present invention. 
         FIG. 2  is a bottom plan view of the razor cartridge of  FIG. 1 . 
         FIG. 3  is a top plan view of the blade unit of  FIG. 1  shown without the frame. 
         FIG. 4  is a perspective view of the blade unit of  FIG. 3 . 
         FIG. 5  is a bottom plan view of the frame of  FIG. 1  shown without the blade unit. 
         FIG. 6  is a perspective view of the frame of  FIG. 5 . 
         FIG. 7  is a cross-sectional view of the razor cartridge of  FIG. 1  taken along section line  7 - 7 . 
         FIG. 8  is a cross-sectional view of another razor cartridge of the present invention. 
         FIG. 9  is a cross-sectional view of another razor cartridge of the present invention. 
         FIG. 10  is a cross-sectional view of another razor cartridge of the present invention. 
         FIG. 11  is a cross-sectional view of another razor cartridge of the present invention. 
         FIG. 12  is a top plan view of another razor cartridge of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to  FIGS. 1-2 , there is shown a razor cartridge  20 . The razor cartridge  20  comprises a blade unit  22  and a frame  40  secured to and surrounding the blade unit  22 . The blade unit  22  comprises a plurality of blades  23  each comprising a blade edge  24 . 
     Referring now to  FIGS. 3-4 , the blade unit  22  is provided with first side wall  25 , second side wall  26 , and end walls  27  and  28  interconnecting the first side wall  25  and the second side wall  26 . The first side wall  25  and the second side wall  26  are provided with first connection members  30  and second connection members  32 . Preferably, first connection members  30  comprise projections  31  extending outwardly from each of first and second side walls  25  and  26 . Preferably, second connections members  32  comprise recesses  33  in each of the first and second side walls  25  and  26 . 
     Blades  23  are secured within blade unit  22  by a pair of clips  35 . Each clip  35  is positioned at an end of blade unit  22  adjacent to end walls  27  and  28 . Blades  23  are secured within blade unit  22  by clips  35  such that blade edges  24  contact the bottom surface of clips  35 . Blades  23  extend along respective parallel blade axes  36 . 
     Referring now to  FIGS. 5-6 , frame  40  is provided with a first interior wall  43  and a second interior wall  44  spaced apart from first interior wall  43  to define an opening  45 . Opening  45  is sized and shaped to receive blade unit  22 . The first interior wall  43  and the second interior wall  44  are provided with first connection members  46  and second connection members  48 . Preferably, first connection members  46  comprise notches  47  in each of the first and second interior walls  43  and  44 . Preferably, the second connection members  48  comprise projections  49  extending outwardly from each of the first and second interior walls into opening  45 . 
     First connection members  46  on interior walls  43  and  44  are adapted to receive first connection members  30  on side walls  25  and  26 . Second connection members  48  on interior walls  43  and  44  are adapted to receive second connection members  32  on side walls  25  and  26 . In securing the frame  40  to the blade unit  20  the projections  31  slide into notches  47  and projections  49  snap into recesses  33 . 
     Referring now to  FIGS. 1 and 2  frame  40  has a perimeter  50 . Perimeter  50  of frame  40  defines a razor cartridge perimeter  51  for razor cartridge  20 . Perimeter  50  comprises a front surface  52 , a rear surface  53  and a pair of side surfaces  54  extending from front surface  52  to rear surface  53 . Frame  40  also has an upper surface  62  and an opposing lower surface  64 . 
     Referring now to  FIGS. 2, 5 and 6 , at each end of frame  40  there is a pivoting structure  55 . Pivoting structure  55  includes an arm  56  extending from interior surface  57  of frame  40  to first interior wall  43  to define a recess  58 . Recess  58  of pivoting structure  55  defines the pivot axis  60  for the razor cartridge  20  and while the pivot axis  60  is within the recess  58  it is not the same as recess  58 . 
     Pivot axis  60  is located within frame  40 , below upper surface  62 , above lower surface  64 , and in front of the blade axes  36 . The pivot axis  60  divides the razor cartridge  20  into a front portion  70  and a rear portion  74 . Front portion  70  extends from pivot axis  60  to front surface  52 . Rear portion  74  extends from pivot axis  60  to rear surface  53 . Preferably, the front portion is less than the rear portion. Preferably, the front portion  70  extends from the pivot axis  60  to the front surface  52  by a distance from about 6 mm to about 12 mm. Preferably, the rear portion  74  extends from the pivot axis  60  to the rear surface  53  by a distance from about 15 mm to about 20 mm. 
     Referring now to  FIG. 1 , the front portion  70  of upper surface  62  includes guard  80 . Guard  80  is that portion of upper surface  62  of frame  40  that contacts the skin prior to or before blade edges  23 . Guard  80  preferably comprises an elastomeric member  82 . 
     The rear portion  74  of upper surface  62  includes a cap  84 . Cap  84  is that portion of upper surface  62  of frame  40  that contacts the skin after blade edges  23 . Cap  84  preferably comprises a lubrication member  86 . 
     Referring now to  FIG. 7 , blade edges  24  of blades  23  define a blade plane  90 . In this embodiment pivot axis  60  is located in front of blade axes  36  and thus closer to front surface  52  than rear surface  53 . Pivot axis  60  is positioned within frame  40 , below upper surface  62  and above lower surface  64  such that a line  92  drawn through pivot axis  60  perpendicular to blade plane  90 , intersects upper surface  62  at a pivot frame intersection location  93 . A tangent line, such as tangent line  94 , drawn along upper surface  62  at pivot frame intersection location  93  will always be parallel to blade plane  90 . This is one requirement for properly positioning of the pivot axis  60  within frame  40 . 
     The second requirement for proper positioning of pivot axis  60  within frame  40  is that the frame  40  must have a first planar surface on the upper surface  62  in front of pivot frame intersection location  93  and a second planar surface on the upper surface located behind the pivot frame intersection location  93  and that these two surfaces be coplanar with one another. As seen in  FIG. 7 , first planar surface  96  on upper surface  62  is in front of pivot frame intersection location  93  and second planar surface  97  on upper surface  62  is located behind the pivot frame intersection location  93 . The first planar surface  96  is coplanar with the second planar surface  97 . The first planar surface  96  extends along upper surface  62  from line  92  to line  98  and second planar surface  97  extends along upper surface  62  from line  92  to line  99 . 
     Referring now to  FIG. 8 , blade edges  24  of blades  23  define a blade plane  90 . In this embodiment pivot axis  60  is located in behind blade axes  36  and thus closer to rear surface  53  than front surface  52 . Pivot axis  60  is positioned within frame  40 , below upper surface  62  and above lower surface  64  such that a line  92  drawn through pivot axis  60  perpendicular to blade plane  90 , intersects upper surface  62  at a pivot frame intersection location  93 . A tangent line, such as tangent line  94 , drawn along upper surface  62  at pivot frame intersection location  93  will always be parallel to blade plane  90 . This is one requirement for properly positioning of the pivot axis  60  within frame  40 . 
     The second requirement for proper positioning of pivot axis  60  within frame  40  is that the frame  40  must have a first planar surface on the upper surface  62  in front of pivot frame intersection location  93  and a second planar surface on the upper surface located behind the pivot frame intersection location  93  and that these two surfaces be coplanar with one another. As seen in  FIG. 8 , first planar surface  96  on upper surface  62  is in front of pivot frame intersection location  93  and second planar surface  97  on upper surface  62  is located behind the pivot frame intersection location  93 . The first planar surface  96  is coplanar with the second planar surface  97 . The first planar surface  96  extends along upper surface  62  from line  92  to line  98  and second planar surface  97  extends along upper surface  62  from line  92  to line  99 . 
     Referring now to  FIG. 9 , a first shaving blade  101  extends along a first blade axis  102  and a last shaving blade  103  extends along a last blade axis  104 . A second shaving blade  105  positioned between first shaving blade  101  and last shaving blade  103  extends along a second blade axis  106 . Blade edges  124  of blades  101 ,  103  and  105  define a blade plane  190 . In this embodiment pivot axis  160  is located in between first blade axis  102  and last blade axis  104 . The pivot axis  160  is spaced equidistant from front surface  152  and rear surface  153 . Pivot axis  160  is positioned within frame  140  below upper surface  162  and above lower surface  164  such that a line  192  drawn through pivot axis  160  perpendicular to blade plane  190 , intersects upper surface  162  at a pivot frame intersection location  193 . A tangent line, such as tangent line  194 , drawn along upper surface  162  at pivot frame intersection location  193  will always be parallel to blade plane  190 . This is one requirement for properly positioning of the pivot axis  160  within frame  140 . 
     The second requirement for proper positioning of pivot axis  160  within frame  140  is that the frame  140  must have a first planar surface on the upper surface  162  in front of pivot frame intersection location  193  and a second planar surface on the upper surface located behind the pivot frame intersection location  193  and that these two surfaces be coplanar with one another. As seen in  FIG. 9 , first planar surface  196  on upper surface  162  is in front of pivot frame intersection location  193  and second planar surface  197  on upper surface  162  is located behind the pivot frame intersection location  193 . The first planar surface  196  is coplanar with the second planar surface  197 . The first planar surface  196  extends along upper surface  162  from line  192  to line  198  and second planar surface  197  extends along upper surface  162  from line  192  to line  199 . 
     Referring now to  FIG. 10 , a first shaving blade  101  extends along a first blade axis  102  and a last shaving blade  103  extends along a last blade axis  104 . A second shaving blade  105  positioned between first shaving blade  101  and last shaving blade  103  extends along a second blade axis  106 . Blade edges  124  of blades  101 ,  103  and  105  define a blade plane  190 . In this embodiment pivot axis  160  is located at the first blade axis  102 . The pivot axis  160  is spaced closer to front surface  152  than rear surface  153 . Pivot axis  160  is positioned within frame  140  below upper surface  162  and above lower surface  164  such that a line  192  drawn through pivot axis  160  perpendicular to blade plane  190 , intersects upper surface  162  at a pivot frame intersection location  193 . A tangent line, such as tangent line  194 , drawn along upper surface  162  at pivot frame intersection location  193  will always be parallel to blade plane  190 . This is one requirement for properly positioning of the pivot axis  160  within frame  140 . 
     The second requirement for proper positioning of pivot axis  160  within frame  140  is that the frame  140  must have a first planar surface on the upper surface  162  in front of pivot frame intersection location  193  and a second planar surface on the upper surface located behind the pivot frame intersection location  193  and that these two surfaces be coplanar with one another. As seen in  FIG. 10 , first planar surface  196  on upper surface  162  is in front of pivot frame intersection location  193  and second planar surface  197  on upper surface  162  is located behind the pivot frame intersection location  193 . The first planar surface  196  is coplanar with the second planar surface  197 . The first planar surface  196  extends along upper surface  162  from line  192  to line  198  and second planar surface  197  extends along upper surface  162  from line  192  to line  199 . 
     Referring now to  FIG. 11 , a first shaving blade  101  extends along a first blade axis  102  and a last shaving blade  103  extends along a last blade axis  104 . A second shaving blade  105  positioned between first shaving blade  101  and last shaving blade  103  extends along a second blade axis  106 . Blade edges  124  of blades  101 ,  103  and  105  define a blade plane  190 . In this embodiment pivot axis  160  is located at the second blade axis  104 . The pivot axis  160  is spaced closer to rear surface  153  than front surface  152 . Pivot axis  160  is positioned within frame  140  below upper surface  162  and above lower surface  164  such that a line  192  drawn through pivot axis  160  perpendicular to blade plane  190 , intersects upper surface  162  at a pivot frame intersection location  193 . A tangent line, such as tangent line  194 , drawn along upper surface  162  at pivot frame intersection location  193  will always be parallel to blade plane  190 . This is one requirement for properly positioning of the pivot axis  160  within frame  140 . 
     The second requirement for proper positioning of pivot axis  160  within frame  140  is that the frame  140  must have a first planar surface on the upper surface  162  in front of pivot frame intersection location  193  and a second planar surface on the upper surface located behind the pivot frame intersection location  193  and that these two surfaces be coplanar with one another. As seen in  FIG. 11 , first planar surface  196  on upper surface  162  is in front of pivot frame intersection location  193  and second planar surface  197  on upper surface  162  is located behind the pivot frame intersection location  193 . The first planar surface  196  is coplanar with the second planar surface  197 . The first planar surface  196  extends along upper surface  162  from line  192  to line  198  and second planar surface  197  extends along upper surface  162  from line  192  to line  199 . 
     Referring now to  FIG. 12 , there is shown a razor cartridge  220 . The razor cartridge  220  comprises a blade unit  222  and a frame  240  secured to and surrounding the blade unit  222 . The blade unit  222  comprises a plurality of blades  223  each comprising a blade edge  224 . Razor cartridge  220  is identical to razor cartridge  20  of  FIG. 1  except that no clips are used to secure blades  223  within blade unit  222 . Instead, a portion of frame  240  extends over each end of blade unit  222  to maintain blades  223  within blade unit  222 . A partial cut-away of one end of frame  240  in  FIG. 12  reveals the underlying blades  223  within blade unit  222 . 
     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”. 
     All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. 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.