Abstract:
A knife is described having a handle that at least partially conforms to the palm of a user and includes an arcuate surface opposite the palm portion of the handle that may be utilized by the user to provide additional leverage and force to a blade cutting edge. The handle also includes finger holds formed in the handle between the palm portion and arcuate portions of the handle. An embodiment further includes an interchangeable blade extending out of the handle from the arcuate surface and may also include an actuable blade lock that fixes a portion of an interchangeable blade within the handle.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not Applicable 
       TECHNICAL FIELD 
       [0002]    This invention pertains generally to knives and more particularly to knives having replaceable blades. Further, knives constructed in accordance with the present invention are particularly useful to hunters for gutting, skinning, fleshing, or even quartering of an animal. 
       BACKGROUND 
       [0003]    Generally, knives having blades extending from a handle parallel with a longitudinal axis of the handle are known in the art. Other knives have been described that include a uniquely shaped blade extending from the handle. Many of these knives are designed for a particular cutting function. By way of example, a prior knife described in U.S. Pat. Application Publication No. 2010/0146792A1 is particularly well suited for skinning an animal and includes spreading members disposed at the forward most portion of a knife blade to spread apart two portions of an animal hide when skinning an animal. Similarly, U.S. Pat. No. 5,033,987 describes a knife particularly well suited for skinning and cutting animal carcasses. 
         [0004]    Other prior devices describe knives that apply cutting forces utilizing the wrist as a pivot point, rather than utilizing the strength of the user&#39;s forearm, triceps, biceps and shoulder muscles. For example, U.S. Pat. No. 5,845,404 (at least at col. 10, lines 25-39) describes a knife that utilizes the hand or wrist as the pivot point for the blade, thus requiring a force to be applied on the handle near the wrist. There is a continued need for an ergonomic knife that reduces the force applied near the user&#39;s wrist while effectively providing a cutting force to the blade. 
       SUMMARY 
       [0005]    Embodiments according to aspects of the invention include a knife assembly having a handle, a blade, a palm receiving portion of the handle, and a blade receiving portion of the handle, where the blade receiving portion opposes the palm receiving portion and forms a convex surface extending away from the palm receiving portion. The handle includes finger holds extending through the handle. Interchangeable blades extend outwardly from the convex portion of the handle. The user is expected to grip the handle in the palm of the hand and utilize the convex surface of the handle as a pivot point, thereby transferring the force required of the user&#39;s arm to the rearward portion of the forearm and shoulder. In another embodiment of the invention the knife assembly further includes a blade lock engaged with the blade and the handle. Without limitation intended, another embodiment of the invention includes a palm receiving portion having a concave surface formed in the palm receiving portion. 
         [0006]    The accompanying drawings, which are incorporated in and constitute a portion of this specification, illustrate embodiments of the invention and, together with the detailed description, serve to further explain the invention. The embodiments illustrated herein are presently preferred; however, it should be understood, that the invention is not limited to the precise arrangements and instrumentalities shown. For a fuller understanding of the nature and advantages of the invention, reference should be made to the detailed description in conjunction with the accompanying drawings. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0007]    In the various figures, which are not necessarily drawn to scale, like numerals throughout the figures identify substantially similar components. 
           [0008]      FIG. 1  is a perspective view of the knife assembly in accordance with an embodiment of the invention; 
           [0009]      FIG. 2  is a partial exploded perspective view of the knife assembly in accordance with an embodiment of the invention 
           [0010]      FIG. 3  is a partial exploded perspective view of the knife assembly in accordance with an embodiment of the invention; 
           [0011]      FIG. 4  is a perspective view of the lower handle assembly of the knife assembly in accordance with an embodiment of the invention; 
           [0012]      FIG. 5  is a perspective view of the upper handle assembly of the knife assembly in accordance with an embodiment of the invention; 
           [0013]      FIG. 6  is a perspective view of the underside of the upper handle assembly of the knife assembly in accordance with an embodiment of the invention; 
           [0014]      FIG. 7  is a perspective view of the blade lock of the knife assembly in accordance with an embodiment of the invention; 
           [0015]      FIG. 8  is a perspective view of a blade insert of the knife assembly in accordance with an embodiment of the invention; 
           [0016]      FIG. 9  is a perspective view of a blade insert of the knife assembly in accordance with an embodiment of the invention; and 
           [0017]      FIG. 10  is a perspective view of a blade insert of the knife assembly in accordance with an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    The following description provides detail of various embodiments of the invention, one or more examples of which are set forth below. Each of these embodiments are provided by way of explanation of the invention, and not intended to be a limitation of the invention. Further, those skilled in the art will appreciate that various modifications and variations may be made in the present invention without departing from the scope or spirit of the invention. By way of example, those skilled in the art will recognize that features illustrated or described as part of one embodiment, may be used in another embodiment to yield a still further embodiment. Thus, it is intended that the present invention also cover such modifications and variations that come within the scope of the appended claims and their equivalents. 
         [0019]    The knife assembly of the present invention includes a handle assembly and an interchangeable blade. The handle assembly includes finger holds and is curved to fit in the palm of a user&#39;s hand. The handle assembly includes a convex curvature opposing the palm receiving curve and at least a portion of the convex curve may be used as a pivot point or leverage surface as the blade is drawn over a cutting surface. The handle assembly may include a blade lock that actuates between a locked and open position. Alternatively, the blade lock may engage the blade in a fixed position, requiring disassembly of the handle assembly to replace the blade. 
         [0020]    A user of the knife assembly will appreciate that the knife assembly of the present invention is particularly useful for gutting, skinning, fleshing, or even quartering of an animal, but is also particularly useful as a utility knife, and is also particularly useful as a trade knife. For example, without limitation intended, a carpet cutting blade of suitable known construction may be inserted in the handle assembly and the convex curve of the handle is particularly well suited to slide along the carpet while pressure is applied to the blade while cutting the carpet. 
         [0021]    Turning attention now to the Figures, embodiments of the knife assembly or versatile knife with removable blade  10  of the present invention will now be described in more detail. The knife assembly  10  is generally shown in  FIGS. 1-3  including a handle  12 , blade  14 , finger holds  18  and  20 , and fastener  24 . An embodiment of the knife assembly shown in  FIGS. 1 and 3  includes a blade lock  16  and actuation spring  26 . The embodiment of the knife assembly shown in  FIG. 2  includes blade locking pins  32 . Lower handle assembly  40  and upper handle assembly may be constructed to engage together with utilizing a configuration of known construction to snap fit the upper and lower assembly together or may be engaged together with a fastener  40 . The handle assembly  12  includes a concave curvature  22  configured to fit within the palm of a user&#39;s hand. Opposing the curvature  22  is a convex curvature  28  of the handle assembly  12 . The blade  14  extends outwardly from the handle  14  adjacent or near a portion of the convex curvature  28 . The remaining portion of the convex curvature  28  may be utilized by the user to rest on the cutting surface, guide the blade against the cutting surface, or rotate along the cutting surface in a rocking motion. 
         [0022]    Referring now to  FIG. 4 , the lower handle assembly  40  is shown including a rim  42 , blade pocket  44 , spring pocket  46 , blade lock pocket  48  and pivot aperture  50 . The rim is sized to mate and engage with lip  64  of the upper handle assembly  60 . The blade pocket  44  is configured in the shape of a blade  14 . The depth of the pocket  44  is only slightly more than the thickness of the blade  14  to reduce the potential movement of the blade in the pocket  44 . The spring pocket is adapted to receive a compression spring wherein one end of the spring engages a side of the spring pocket  46  and the other end of the spring  26  engages the spring face  34  of the blade lock  16  (refer also to  FIG. 2 ). The blade lock pocket  48  is configured to receive the shape of the blade lock  16  and is sized to allow sufficient rotation of the blade lock  16  within the blade lock pocket  48  to disengage the blade lock  16  from the blade  14 . The pivot aperture is adapted to receive a portion of fastener  24 . 
         [0023]    Referring to  FIGS. 5 and 6 , the upper handle assembly  60  includes a blade support  62 , lip  64 , pivot aperture  66  and inner cavity  68 . The lip  64  engages around the rim  42  and inner cavity  68  is configured to engage with the top planar surface of the lower handle assembly  40 . When the upper handle assembly is engaged with the lower handle assembly, the blade support  62  provides a slight friction fit against blade  14 . In this manner the blade  14  may be slid from the handle assembly, but the blade support  62  further restricts rotation of the blade within the blade pocket  44 . 
         [0024]      FIG. 7  illustrates the blade lock  16  which includes a lever arm  30 , locking finger pin  32 , spring face  34 , pivot aperture  36  and actuation tab  38 . The locking pin  32  engages in a blade notch  82  formed in the blade  14 . A user may apply a force to the actuation tab  38  to rotate the lever arm  30  about pivot aperture  36 . Spring  26  applies a force against spring face  34  to affectively rotate the locking pin  32  into the blade notch  82 . The force applied to the actuation tab must be sufficient to overcome the compression spring  26 . 
         [0025]    Without limitation intended,  FIGS. 8-10  illustrate a variety of interchangeable blades  14  that may be inserted into the handle assembly  12 . Generally a blade of suitable construction includes a blade body  80 , a blade notch  82 , and a cutting edge of the blade.  FIG. 8  illustrates a curved cutting surface  84 ,  FIG. 9  illustrates a straight cutting surface  86  and  FIG. 10  illustrates a hooked cutting surface  88 . The blade notch  82  is sized to engage with the locking pin  32  of the blade lock  14  or with the lock pin  32  as shown in  FIG. 2 . 
         [0026]    Having described the constructional features of embodiments of the invention, the mode of use will next be described. A user selects a blade  14  having a desired cutting configuration and inserts it into blade pocket  44 . The actuation tab  38  may be actuated upwards to reduce the amount of force required to insert the blade  14  into the pocket  44 . Once the blade is inserted the user may release the tab so that the locking pin  32  engages with the blade notch  82 . The user may then hold the handle  12  in the palm of the hand with or without inserting the fore and middle fingers into the finger holds  18  and  20 . The user may select a blade  15  having an angle that allows for rocking the handle on the convex curvature or radius of the handle  12 . By rocking the handle the blade  14  may move in and out of contact with the cutting surface. It has been found that a blade having a 25 degree angle allows for rocking the handle into engagement, but blades having other angles are equally well suited for cutting with the knife assembly of the present invention. When cutting with the blade, the user may press a portion of the convex curvature of the handle  12  against the cutting surface to assist in controlling the depth that the blade extends into the cutting surface. The user may store the cutting portion of the blade inside the handle  12  by removing the blade and inserting the cutting point into the blade pocket  44  until the blade notch  82  engages with the locking pin  32 . 
         [0027]    These and various other aspects and features of the invention are described with the intent to be illustrative, and not restrictive. This invention has been described herein with detail in order to comply with the patent statutes and to provide those skilled in the art with information needed to apply the novel principles and to construct and use such specialized components as are required. It is to be understood, however, that the invention can be carried out by specifically different constructions, and that various modifications, both as to the construction and operating procedures, can be accomplished without departing from the scope of the invention. Further, in the appended claims, the transitional terms comprising and including are used in the open ended sense in that elements in addition to those enumerated may also be present. Other examples will be apparent to those of skill in the art upon reviewing this document.