Abstract:
A hand held cutting tool is provided for use with at plurality of different tool elements each having a two-sided shank portion of distinct longitudinal profile. The hand held cutting tool is described as comprising: (a) a barrel portion defining an equal plurality of longitudinally extending channels therewithin, with each said channel having a complimentary outline shape and otherwise dimensioned to receive one of said shank portions therewithin in close fitting relation, with a first side of said shank portion positioned adjacent the base of said channel; (b) one or more housing means mounted on the barrel portion for selectively contacting said shank portion remote from said first side to retain the respective tool element in mated held-fast relation within each said channel; and, (c) a handle portion attached to said barrel portion.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates generally to the field of hand tools, and more particularly to those having interchangeable tool elements, such as a knife blade or the like. 
       BACKGROUND OF THE INVENTION 
       [0002]    The field of hand held tools is one in which various previously known types of hand tools may have had interchangeable tool elements. For example, screw driver handles are known that have interchangeable screw driver bits for accommodating screw heads having different drive patterns. Also, utility knife handles are known that have interchangeable cutting blades. The vast majority of such utility knife handles provide for the use of a single type of cutting blade, typically being the standard quadrilateral-shaped utility blades having upper and lower parallel edges, the lower of which is typically sharpened and of generally longer length than the upper edge, with the upper edge typically being unsharpened and having one or more notches designed to index with a holding means mounted in the body of the utility knife. The other two opposed edges are also typically unsharpened, and are generally shorter and angled congruently, but in opposite directions from one another, to provide for a reversible blade having two points. A prior art utility knife blade of this general type is shown at reference numeral  21  in attached  FIG. 1   a.    
         [0003]    Most utility knives provide for replacement of a blade when it becomes dull or broken, and some even provide for interchangeability of the standard utility knife blades  21  with blades having different profiles. For example a standard utility knife blade  21  may be replaced with a hooked blade (not shown) for cutting linoleum or the like. 
         [0004]    Typically, however, the length and style of blades that can be interchanged with the handles of known utility knives are somewhat limited, with all being of the same general thickness, length and shank profile, as such, the shank portion must be accepted by, and held fast within, the blade holding means associated with the handle of the knife. In other words, the means for releasably holding the knife blade by its shank portion is typically static in the prior art, in the sense that such means is only capable of accommodating one particular profile and thickness of blade shank. Similarly, known screw driver handles accommodating interchangeable tool elements (in the form of screw driver bits) will (in the absence of having an adjustable chuck mechanism), only accept screw driver bits of a shank with a single cross-sectional profile. This is particularly limiting when one considers that limiting the length and/or thickness of the shank portion of a tool element will also place significant limitations on the overall length and size of the tool element that can be successfully anchored and supported thereby. Thus, prior art hand tools for use with interchangeable tool elements typically have relatively small handles for small length tool elements, and relatively larger handles for longer length tool elements. 
         [0005]    Another manner of providing different tool elements in association with a single hand tool takes the form of the well-known Swiss Army Knife™, available from, for example, Wenger S. A., of Delemont, Switzerland, which may have eight or more tool elements associated with a single knife handle. These tool elements may take many forms in addition to screw driver bits, sawing blades or cutting blades, including, for example and without limitation, corkscrews, can openers, scissors, magnifying glasses, cutlery items namely, forks, spoons, knives and the like, and the term “tool element” is used herein to have an equally broad scope of coverage. Nonetheless, the Swiss Army Knife™ solution for providing different tool elements in association with a single hand tool is different from that of the present invention, as the Swiss Army Knife™ uses a separate mounting means for attachment of each respective tool element to the body of the knife handle, which means that such tool elements are not truly “interchangeable” within the meaning of this word as used herein. 
       SUMMARY OF THE INVENTION 
       [0006]    In accordance with the present invention there is disclosed a hand held cutting tool which comprises and/or is for use with one of the following parts: a barrel portion having a plurality of longitudinally extending channels therewithin; at least two interchangeable tool elements each having different longitudinal cross-sectional shank profiles; and a handle portion. 
         [0007]    According to one aspect of the invention, the internal chamber may preferably, but need not necessarily, be adapted to accommodate therein at least two interchangeable tool elements with each having different longitudinal cross-sectional shank profiles. 
         [0008]    According to another aspect of the invention, the barrel portion may preferably, but need not necessarily, comprise a dividing member with recessed receiving portions formed therein that may preferably, but need not necessarily, correspond substantially with the cross-sectional shank profile of one of the two tool elements. 
         [0009]    According to another aspect of the invention, a shank portion of a first one of the tool elements may preferably, but need not necessarily, be operable to mate with the recessed receiving portion of a first side of the dividing member and a shank portion of a second one of said tool elements may preferably, but need not necessarily, be operable to mate with the recessed receiving portion of a second side of the dividing member. 
         [0010]    According to still another aspect of the invention, the barrel portion may preferably, but need not necessarily, comprise a dividing member with substantially flat non-recessed surfaces and at least two recessed receiving members in contacting relation with opposite sides of the dividing member, the recessed receiving members each having a recessed receiving portion formed therein that corresponds substantially with the cross sectional shank profile of one of the two tool elements. 
         [0011]    According to yet another aspect of the invention, a shank portion of a first one of the tool elements, may preferably but need not necessarily, be operable to mate with the recessed receiving portion of a first one of the recessed receiving members and a shank portion of a second one of the tool elements, may preferably but need not necessarily, be operable to mate with the recessed receiving portion of a second one of the recessed receiving members. 
         [0012]    According to still yet another aspect of the invention, the barrel portion of the cutting tool may preferably, but need not necessarily further comprise one or more securing/guard plates overlying the shank portion of a selected one of the tool elements, and pivotally mounted on the barrel portion, the securing plates may preferably, but need not necessarily be adapted to retain each of said tool elements within the barrel portion of the hand tool. 
         [0013]    According to a further aspect of the invention the barrel portion, may preferably but need not necessarily, further comprise a locking member pivotally mounted on an upper surface of the barrel portion and movable from an open unlocked position substantially transverse to the upper surface of the barrel portion to a closed locked position substantially parallel to the upper surface of the barrel position such that, in the closed locked position, the locking member overlies the upper surface of the barrel portion and an upper edge of one or more of the securing plates when the one or more securing plates overlay the shank portion of at least one of the tool elements. 
         [0014]    According to a yet further aspect of the invention, the handle and barrel portion of the hand tool, may preferably but need not necessarily, be pivotally attached to each other by means of a first pivot and may preferably be pivotable thereabout. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    The novel features which are believed to be characteristic of the hand held cutting tool according to the present invention, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following drawings in which various embodiments of the invention will now be illustrated by way of example. It is expressly understood, however, that the drawings are for the purpose of illustration and description only, and are not intended as a definition of the limits of the invention. In the accompanying drawings: 
           [0016]      FIG. 1   a  is a side elevational view of a hand tool according to a first embodiment of the present invention with one cutting element inserted therein and with one cutting element removed therefrom; 
           [0017]      FIG. 1   b  is a side elevational view of the hand tool opposite to the side view shown in  FIG. 1   a , on a reduced scale; 
           [0018]      FIG. 1   c  is an front perspective view of the hand tool shown in  FIG. 1   a;    
           [0019]      FIG. 2  is an exploded side perspective view of the hand tool of  FIG. 1   a , shown in a first partially disassembled configuration; 
           [0020]      FIG. 2   a  is a partially exploded front perspective view of the hand tool shown in  FIG. 2 ; 
           [0021]      FIG. 2   b  is an enlarged side elevational view of the encircled area A of  FIG. 2   a;    
           [0022]      FIG. 3  is a further exploded front perspective view of the hand tool of  FIG. 2   a;    
           [0023]      FIG. 3   a  is a front elevational view of the hand tool shown in  FIG. 3 ; 
           [0024]      FIG. 3   b  is a front perspective view similar to  FIG. 3   a , with a first cutting tool shown removed therefrom; 
           [0025]      FIG. 3   c  is a side perspective view similar to  FIG. 3   b , shown with a second cutting tool inserted therein; 
           [0026]      FIG. 4   a  is a further exploded side perspective view of the hand tool of  FIG. 3   c;    
           [0027]      FIG. 4   b  is an front perspective view of the hand tool shown in  FIG. 4   a;    
           [0028]      FIG. 5   a  is a further exploded front perspective view of the hand tool of  FIG. 4   a , shown with the second cutting tool removed therefrom; 
           [0029]      FIG. 5   b  is a further exploded front perspective view of the hand tool of  FIG. 5   a;    
           [0030]      FIG. 5   c  is a fully exploded front perspective view of the hand tool of  FIG. 5   b;    
           [0031]      FIG. 6  is an exploded side perspective view of the hand tool of  FIG. 5   c , from the opposite side to the side shown in  FIG. 5   c;    
           [0032]      FIG. 7   a  is a side elevational view of a second hand tool according to another embodiment of the present invention, with the handle portion removed and with two different cutting elements simultaneously inserted therein; 
           [0033]      FIG. 7   b  is a side elevational view of the hand tool of  FIG. 7   a , from a side opposite to the side shown in  FIG. 7   a;    
           [0034]      FIG. 7   c  is an front perspective view of the embodiment shown in  FIG. 7   a;    
           [0035]      FIG. 8  is a partially exploded side perspective view of the hand tool of  FIG. 7   a , shown in a first partially disassembled configuration; 
           [0036]      FIG. 9   a  is a front elevational view of the hand tool shown in  FIG. 8 , with the cutting element also removed; 
           [0037]      FIG. 9   b  is a further exploded side perspective view of the hand tool of  FIG. 9   a , shown in a second partially disassembled configuration; 
           [0038]      FIG. 10  is a side perspective view of the hand tool of  FIG. 9   b , from a side opposite to the side shown in  FIG. 9   b;    
           [0039]      FIG. 10   a  is a further exploded side perspective view of the hand tool of  FIG. 10 , shown in a third partially disassembled configuration; 
           [0040]      FIG. 11  is a top plan view of the hand tool shown in  FIG. 10   a;    
           [0041]      FIG. 12  is an exploded side elevational view of the hand tool shown in  FIG. 10   a;    
           [0042]      FIG. 13  is a further exploded side elevational view of the hand tool of  FIG. 12 , shown in a completely disassembled configuration, with a second cutting element shown removed therefrom; 
           [0043]      FIG. 13   a  is a side elevational view, on an enlarged scale, of the barrel portion and of a shank portion of the second cutting element shown in  FIG. 13 ; 
           [0044]      FIG. 14  is an exploded rear elevational view of the hand tool shown in  FIG. 11 ; 
           [0045]      FIG. 15  is front perspective view of yet another embodiment of a hand tool according to the present invention; 
           [0046]      FIG. 16  is an exploded right side perspective view of the hand tool of  FIG. 15 , shown in a partially disassembled configuration; 
           [0047]      FIG. 17  is an exploded left side elevational view of the hand tool of  FIG. 16 , shown in a completely disassembled configuration; 
           [0048]      FIG. 17   a  is an enlarged left side elevational view of the shank portion of the second cutting element and its corresponding recessed receiving portion of the hand tool shown in  FIG. 17 ; and, 
           [0049]      FIG. 18  is an exploded top plan view of the hand tool shown in  FIG. 17 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0050]    Referring now to  FIGS. 1 to 6  of the drawings, there is shown a hand tool in the form of a knife  30  having a pistol grip handle portion  32  and a barrel portion  34 . As best seen in  FIGS. 1   a  and  1   b , the pistol grip handle portion  32  is mounted to the barrel portion  34  by means of a first pivot  36 , and is selectively rotatable thereabout between an inline position having its longitudinal axis substantially aligned with that of the barrel portion  34  (as shown in  FIG. 1   a ) and an angled position having its longitudinal axis substantially transverse to that of the barrel portion  34  (which latter position is not shown in the Figures). 
         [0051]    In one embodiment, the handle portion  32  and barrel portion  34  may be formed from a resilient material, preferably a synthetic plastic material and/or a substantially rigid material, preferably a metal material. 
         [0052]    As best seen in  FIGS. 2 ,  2   a  and  3 , the pistol grip handle portion  32  is selectively locked against rotation about first pivot  36  in a selected one of its two described positions by respective locking engagement of pawl tooth  31  positioned adjacent a first end of pawl lever  40  with first  44  and second  46  turkey spurs positioned on the posterior end of the recessed receiving portion  49   c . The pawl lever  40  is itself pivotally mounted for rotation about a second pivot  50 , with a torsion spring  52  (as best seen in  FIG. 2 ) biasing the pawl lever  40  into said locking engagement. A storage compartment  108  for storing extra utility blades  21  within the body of the knife  30  is optionally mounted on the barrel portion  34  in swing down relation about pivot pin  110 . A locking means  114  for this compartment  108  is also optionally provided, which locking means  114  is activated by a push-button mechanism  112  located on the rear end of the pistol grip handle portion  32 . Contoured side panels  115  and  116  are provided for mounting on opposite sides of the pistol grip handle portion  32  for aesthetic reasons and to fill out same for the comfort of users. The side panels  115 ,  116  may be rubberized or otherwise cushioned. A belt clip  117  of resilient metal or plastic material is also optionally mounted on one side of the barrel portion  34 . These features are not essential to the invention, but are ancillary arrangements. 
         [0053]    The embodiments of the invention depicted in  FIGS. 7   a  to  18  are shown for simplicity of illustration with the handle portion  32  removed. However, it is to be understood that an analogous handle portion  32  to that described in the foregoing paragraphs is also operable with the barrel portion  34  shown in  FIGS. 7   a  to  18 . 
         [0054]    As best seen in  FIG. 3   a , the barrel portion  34  is formed so as to accommodate therein different tool elements, such as, for example, the utility knife blade  21  and a wallboard saw blade  22 , each having shank portions,  47   a  (as best seen in  FIG. 1   a ) and  47   b  (as best seen in  FIG. 2 ), of different lengths, heights and thicknesses along their respective shank lengths. More particularly, the shank portions  47   a ,  47   b  of the different tool elements each have distinct longitudinal profiles, meaning that each shank portion  47   a ,  47   b  has a distinct shape when viewed along the length of their longitudinal axis (i.e. a line parallel to the blade surface running lengthwise from the front of the blade to the shank portions thereof). 
         [0055]    In one embodiment, as seen in  FIG. 1   a  and as previously discussed, blade  21  is a conventional utility blade, which has a shank height  21   x . In contrast, blade  22  is a much longer wallboard saw blade, having a shank height  22   x , as best seen in seen in  FIG. 2 . Shank height  21   x  is greater than shank height  22   x.    
         [0056]    In another embodiment, although not shown in the accompanying drawings, the wallboard blade  22  may have a plurality of rearwardly positioned indexing notches (not shown) defined by its top edge so as to provide greater resistance to rotational moments generated during use. In such an alternate configuration, it may be appreciated that the length of the shank (not shown) of wallboard saw blade  22  may be greater than the length of the shank of utility blade  21 , as measured rearwardly (i.e. toward the rear of the cutting tool  30 ) from the congruent and congruently spaced indexing notches  25 , 25  (shown in  FIG. 1   a  for utility blade  21  and not shown for the saw blade  22 ) defined by the top edges of each blade  21 , 22 . 
         [0057]    As may be best appreciated from  FIG. 3   a , the thickness of the wallboard saw blade  22  may preferably be markedly greater than that of the utility blade  21 . 
         [0058]    The features of the barrel portion  34  that facilitate the interchangeability of blades having different lengths, heights and/or thicknesses will now be described in greater detail to illustrate the underlying principles of the present invention. 
         [0059]    In one embodiment according to the present invention, as best seen in  FIGS. 1   a  to  6 , the barrel portion  34  comprises two opposed housing segments, being the first barrel housing segment  48  (as best seen in  FIG. 5   a ) and a second barrel housing segment  49  (as best seen in  FIG. 4   b ). The two housing segments  48  and  49  are not mirror images of one another, but have different recessed profiles formed on their respective inner surfaces  48   a  (as best seen in  FIGS. 5   a  and  5   b ) and  49   a  (as best seen in  FIGS. 2   a  and  3   a ), and mate with dividing member  80  (as best seen in  FIG. 3   b ), which is situated along a medial plane of the barrel portion  34 , to form at least two internal chambers, each having respectively different cross-sectional heights and thickness along the length of their longitudinal axis, with the differences therein accommodating corresponding differences in the cross-sectional height and thickness of the shank portion of an associated blade adapted to be positioned by longitudinally rearward sliding movement into a respective one of said chambers. 
         [0060]    As best seen in  FIGS. 1   c ,  3   c ,  4   a ,  4   b ,  5   a  and  5   b , the first barrel housing segment  48 , may comprise a barrel housing portion  48   b  and a recessed receiving portion  48   c  in contacting relation with each other. The barrel housing portion  48   b  forms part of the exterior surface of the first barrel housing segment  48 , whereas the recessed receiving portion  48   c  is operable to receive therein a selected one of utility blade  21  or wall board saw blade  22 . As best seen in  FIGS. 4   a  and  5   a , the recessed receiving portion  48   c  contains a profile that corresponds substantially with the longitudinal profile of utility blade  21 , such that a lateral shank face of the shank portion  47   a  of the utility blade  21  is received within or mates with the recessed receiving portion  48   c.    
         [0061]    Likewise, and as also shown in  FIGS. 1   c ,  2 ,  2   a ,  3 ,  3   a  and  3   b , the second barrel housing segment  49 , may comprise a barrel housing portion  49   b  and a recessed receiving portion  49   c  in contacting relation with each other. The barrel housing portion  49   b  forms part of the exterior surface of the second barrel housing segment  49 , whereas the recessed receiving portion  49   c  is operable to receive therein a selected one of utility blade  21  or wall board saw blade  22 . As best seen in  FIGS. 2 and 2   a , the recessed receiving portion  49   c  contains a profile that corresponds substantially with the longitudinal profile of wall board saw blade  22 , such that a lateral shank face of the shank portion  47   b  of the wallboard saw blade  22  is received within or mates with the recessed receiving portion  49   c.    
         [0062]    It is to be appreciated that the receiving portions  48   c ,  49   c  may be fastened to respective inner surfaces  48   a  (as best seen in  FIG. 5   c ) and  49   a  (as best seen in  FIG. 3   a ) of the barrel housing portions  48   b ,  49   b  via conventional fasteners (e.g. screws, rivets, etc.), not shown. 
         [0063]    As best seen in  FIGS. 1   c ,  3   b ,  3   c ,  4   a ,  4   b  and  5   a , the barrel portion  34  may also be provided with a dividing member  80  for contacting relation with the respective other lateral shank faces of the blades  21 ,  22 . The dividing member may provide further assistance in retaining the respective other shank faces in mated held fast relation within the respective recessed receiving portions  48   c ,  49   c . As best seen in  FIGS. 4   a ,  4   b , and  5   a , the dividing member  80  may preferably be interposed between the recessed receiving portions  48   c ,  49   c . In one embodiment shown in  FIGS. 1   a  to  6 , the dividing member  80  may preferably be a plate having flat non-recessed surfaces on opposite sides thereof with a selected one of said flat non-recessed surfaces in contact with the other lateral shank faces of each of blades  21  and  22 . 
         [0064]    To further assist in retaining the blades  21 ,  22  in the barrel portion  34 , the hand tool  30  may be provided with a blade locking assembly comprised of a rocker member  90  operable to selectively engage at least one shank portion  47   a ,  47   b  against unintentional sliding removal of the blade  21 ,  22 . 
         [0065]    In some embodiments, rocker member  90  (as best seen in  FIG. 5   a ) is removably insertable into a selected one of the internal chambers to selectively engage a selected one of shank portions  47   a ,  47   b  and retain same against unintentional sliding removal of a selected blade  21 ,  22  from the respective one of said internal chambers. 
         [0066]    The rocker member  90 , (as best seen in  FIG. 5   c ) has a thumb-engagement portion  90   a  positioned on its side surface  93  adjacent a first longitudinal end  90   b , and a mounting bearing  90   c  positioned adjacent a second opposite second longitudinal end  90   d  (as best seen in  FIG. 6 ). At least one tooth  91   a  (as best seen in  FIG. 5   b ), may be longitudinally spaced along the bottom surface  95  (as best seen in  FIG. 6 ) of the rocker member  90 . The rocker member  90  is mounted for rotation about its bearing surface  90   c  by means of a pivot stub  97  (as best seen in  FIG. 5   a ) between a raised unlocked configuration (not shown) and a lowered, locked configuration (which configuration is illustrated in all assembly figures), and in which locked configuration engages with the shank of a selected blade  21 ,  22  to hold same fast within its respective internal chamber against unintentional forward sliding movement of the blade out of said respective internal chamber. 
         [0067]    The rocker member  90  (as best seen in  FIG. 5   b ) is biased to the locked position shown in the drawings by means of a coil spring  101  (as best seen in  FIG. 6 ) mounted about pivot stub  97 . The rocker member  90  is moved between its locking and unlocking configuration, respectively, upon urging by a user engaging thumb engagement portion  90   a  mounted on side surface  93  of rocker member  90  and rotating same upwards. 
         [0068]    More particularly, and as best seen in  FIGS. 4   a  and  4   b  when the conventional utility knife blade  21  is fully inserted in a rearward sliding motion into its respective chamber, and the rocker member  90  is thereafter pivoted to its locked configuration, tooth  91   a  engages one of the respective indexing notches  25 ,  25 . Lower shoulder  63  (as best seen in  FIG. 5   b ) formed on an internal face of the recessed receiving portion  48   c  of the first barrel housing segment  48  acts as a stop means to limit rearward sliding movement of the blade  21  within its respective internal chamber. 
         [0069]    In this fully inserted configuration, upward movement of the utility blade  21  is limited by engagement of the upper edge of the blade  21  with upper surface  65  (as best seen in  FIGS. 5   a  and  5   b ) formed on the internal face of the recessed receiving portion  48   c  of the first barrel housing segment  48 . In this fully inserted configuration, downward movement of the utility blade  21  is limited by engagement of the lower sharpened edge of the blade  21  with lower straight edge  62  (as best seen in  FIG. 5   b ) formed on the internal face of the recessed receiving portion  48   c  of the first barrel housing segment  48 . Side-to-side movement of the utility blade  21  is limited by engagement of one side face of the blade  21  with the internal surface  48   a  (as best seen in  FIG. 5   b ) of the first barrel housing portion  48   b , and by engagement of the opposite other side face of the blade  21  with the dividing member  80 . In this manner, the utility blade  21  is secured as against unintended movement during use of the knife  30 , within the respective chamber in which it is mounted. 
         [0070]    Similarly, although not shown in the appended drawings the wall board saw blade  22  may also be provided with a plurality of indexing notches  25 ,  25 . In this embodiment, when the wallboard blade  22  is fully inserted in a rearward sliding motion into its respective internal chamber, and the rocker member  90  is thereafter pivoted to its locked configuration, tooth  91   a  engages one of the respective indexing notches  25 ,  25  (not shown) of blade  22  to securely hold the blade  22  in its respective chamber against forward sliding movement of the blade  22 . 
         [0071]    Additionally, and as best seen in  FIG. 2   b , the medial  22   d  and rear  22   f  trailing edges of the saw blade  22  shank portion  47   b  respectively engage with congruently shaped medial  76  and rear  74  shoulder surfaces, formed on the internal face of the recessed receiving portion  49   c  of the second barrel housing segment  49  to act as stop means limiting rearward sliding movement of the blade  22  within its respective internal chamber. Similarly, an upper shoulder surface  71   a  and a lower shoulder surface  71   b  both of which are also formed on the internal face of the recessed receiving portion  49   c  of the second barrel housing segment  49  and are each respectively engageable with the upper  22   b  and lower  22   h  trailing edges of the blade body portion (which shoulder surfaces  71   a  and  71   b  mark the transition between the blade body portion and the shank portion  47   b ) to limit rearward sliding movement of the blade  22  within its respective internal chamber. 
         [0072]    As also best seen in  FIG. 2   b , in this fully inserted configuration, upward movement of the wallboard saw blade  22  is limited by engagement of the first upper straight edge  22   a , the second upper straight edge  22   c  and the medial straight edge  22   e  of the shank portion  47   b  of the blade  22  with upper straight shoulder surfaces  72   a ,  72   b  and medial straight shoulder surface  72   c , respectively, formed on the internal face of the recessed portion  49   c  of the first barrel housing segment  49 . Referring to  FIG. 2   b , downward movement of the saw blade  22  is limited by engagement of the lower straight edge  22   g  of the shank portion  47   b  of the blade  22  with lower straight shoulder surface  75  formed on the internal face of the recessed portion  49   c  of the first barrel housing segment  49 . Side-to-side movement of the wallboard saw blade  22  is limited by engagement of one side face of the blade  22  with the internal face  49   a  of the second barrel segment  49 , and by engagement of the opposite other side face of the blade  22  with dividing member  80 . Accordingly, the thickness of the blade  22  is substantially the same as the distance between the internal face  48   a  and the dividing member  80  when the barrel segment is fully assembled (see, for example  FIG. 1   c ). In this manner, the saw blade  22  is fully secured as against unintended movement during use of the knife  30  within the respective chamber in which it is mounted. 
         [0073]    Additionally, and as best seen in  FIG. 2   b , the shank portion  47   b  of the saw blade  22  may contain an indexing hole  29  operable to receive therethrough securing means  28  for securing blade  22  to dividing member  80 . It is to be appreciated that the securing means  28  may encompass conventional securing means as by way of non limiting example screws, rivets, pins, bolts, etc. 
         [0074]    Additional features of the barrel portion  34  according to alternate embodiments of the present invention will now be discussed with reference to  FIGS. 7   a  to  18 . It is to be understood that the same reference numerals described in the preceding paragraphs with respect to the embodiment illustrated in  FIGS. 1 to 6  are analogous in structure and function to the same parts bearing the same reference numerals shown in the embodiment shown in  FIGS. 7   a  to  18  and will not, for this reason, be again described in the following paragraphs. 
         [0075]    In the embodiment according to the present invention shown in  FIGS. 7   a  to  14 , the barrel portion  34  is formed from a first barrel housing segment  48 ′ (as best seen in  FIG. 7   a ) and a second barrel housing segment  49 ′ (as best seen in  FIG. 7   b ) and a dividing member  80 ′ (as best seen in  FIG. 7   c ) interposed therebetween. The two housing segments  48 ′,  49 ′ may preferably be mirror images of one another, and mate with the dividing member  80 ′ to form at least two internal chambers and/or longitudinal channels. Each of the longitudinal channels have different cross-sectional heights and thicknesses along the length of their longitudinal axis, with the differences therein accommodating corresponding differences in the cross-sectional height and thickness of the shank portion of an associated blade adapted to be positioned by longitudinally rearward sliding movement into a respective one of said channels. The housing segments  48 ′,  49 ′ are each pivotably mounted to the barrel portion  34  by means of a housing segment pivot  87  (as best seen in  FIGS. 7   a  and  7   b ). 
         [0076]    Of course it is to be appreciated that, in one embodiment (as best seen in  FIGS. 7   c  and  9   a ), the dividing member  80 ′ may be formed with recessed receiving portions  80   a ,  80   b  being integrally molded into opposite inner surfaces of the dividing member  80 ′. 
         [0077]    As best seen in  FIGS. 9   a  and  9   b , the recessed receiving portion  80   a  of the dividing member  80 ′ has a profile that corresponds substantially with the longitudinal profile of utility blade  21  such that a first lateral shank face of the shank portion  47   a  (as best seen in  FIG. 13 ) of the utility blade  21  is received within or mates with the recessed receiving portion  80   a  of the dividing member  80 ′. 
         [0078]    Likewise, as best seen in  FIG. 13 , the recessed receiving portion  80   b  has a profile that corresponds substantially with the longitudinal profile of wallboard blade  22  such that a first lateral shank face of the shank portion  47   b  of blade  22  is received within or mates with the recessed receiving portion  80   b  of the dividing member  80 ′. 
         [0079]    To further assist in retaining the blades  21 ,  22  in the barrel portion  34 , the hand tool  30  may be provided with blade retaining assembly operable to selectively engage a selected one of the shank portions  47   a ,  47   b  against unintentional removal of the blade  21 ,  22 . As best seen in  FIG. 9   b , the blade retaining assembly comprises at least two teeth  92   a ,  92   b , which extend downward from an upper portion  33  of the barrel portion  34 , and are operable to engage with the shank portion  47   a  of the utility blade  21  to hold same fast with its recessed receiving portion  80   a  against unintentional forward sliding movement of the blade but of the barrel portion  34 . 
         [0080]    More particularly, as best seen in  FIG. 8 , when the conventional utility knife blade  21  is fully inserted into hand tool  30  in a rearward sliding motion into its respective chamber, each of the downwardly extending teeth  92   a ,  92   b  engages one of the respective indexing notches  25 ,  25 . The rear edge  21   a  of the utility blade  21  abuts against rear shoulder  60 ′ of the barrel portion  34  which acts as a stop means to limit rearward sliding movement of blade  21  within its respective chamber. 
         [0081]    In this fully inserted configuration, upward movement of the utility blade  21  is limited by engagement of the upper edge of the blade  21  with upper shoulder  65  (as best seen in  FIG. 9   a ) of the dividing member  80 ′. In this fully inserted configuration, downward movement of the utility blade  21  is limited by engagement of the lower sharpened edge of the blade  21  with the lower straight edge  62 ′ of the dividing member  80 ′ (as best seen in  FIG. 9   a ). Side-to-side movement of the utility blade  21  is limited by engagement of the first lateral shank face of the blade  21  with either the dividing member  80 ′ (seen in  FIG. 9   a ) and by engagement of the opposite second lateral shank face of the blade  21  with the inner surface  48   a  (as best seen in  FIG. 9   a ) of the barrel housing segment  48 ′. In this manner, the utility blade  21  is secured as against unintended movement during use of the knife  30 , within the respective chamber in which it is mounted. 
         [0082]    Similarly, although not shown in the appended drawings, the wall board saw blade  22  may also be provided with a plurality of indexing notches  25 ,  25 . In this embodiment, when the wallboard saw blade  22  is fully inserted in a rearward sliding motion into its respective internal chamber, at least one of the downwardly extending teeth  92   a ,  92   b , engages one of the respective indexing notches (not shown) to securely hold the blade  22  in its respective chamber against forward sliding movement of the blade  22 . 
         [0083]    In the embodiment shown in  FIG. 13 , the blade retaining assembly comprises a fastener receiving means  79  formed through dividing member  80 ′ and operable to receive therein a fastener to retain the wallboard saw blade  22  within its respective chamber. Additionally, the shank portion  47   b  of the saw blade  22  may contain an indexing hole  29  operable to receive therethrough a fastener for securing the blade  22  to the dividing member  80 ′. 
         [0084]    Additionally, as best seen in  FIG. 13   a , the medial  22   d  and rear  22   f  trailing edges of the saw blade  22  shank portion  47   b  respectively engage with congruently shaped medial  76 ′ and rear  74 ′ shoulder surfaces, formed on the internal face of the recessed receiving portion  80   b  of the dividing member  80 ′ in  FIG. 13   a  to act as stop means limiting rearward sliding movement of the blade  22  within its respective internal chamber. Similarly, an upper shoulder surface  71   a ′ and a lower shoulder surface  71   b ′ each of which are formed on the internal face of the recessed receiving portion  80   b  of the dividing member  80 ′ are each respectively engageable with the upper  22   b  and lower  22   h  trailing edges of the blade body portion (which shoulder surfaces  71   a ′ and  71   b ′ mark the transition between the blade body portion and the shank portion  47   b ) to limit rearward sliding movement of the blade  22  within its respective internal chamber. 
         [0085]    In this fully inserted configuration, upward movement of the wallboard saw blade  22  is limited by engagement of the first upper straight edge  22   a , the second upper straight edge  22   c  and the medial straight edge  22   e  of the shank portion  47   b  of the blade  22  with upper straight shoulder surfaces  72   a ′,  72   b ′ and medial straight shoulder surface  72   c ′, respectively, each of which are formed on either the internal face of the recessed receiving portion  80   b  of the dividing member  80 ′ in  FIG. 13   a . Downward movement of the saw blade  22  is limited by engagement of the lower straight edge  22   g  of the shank portion  47   b  of the blade  22  with lower straight shoulder surface  75 ′ each of which are formed on either the internal face of the recessed receiving portion  80   b  of the dividing member  80 ′ in  FIG. 13   a . Side-to-side movement of the wallboard saw blade  22  is limited by engagement of one side face of the blade  22  with the internal face  49   a  of the second barrel segment  49 ′, and by engagement of the opposite other side face of the blade  22  with dividing member  80 ′. Accordingly, the thickness of the blade  22  is substantially the same as the distance between the internal face  49   a  (as best seen in  FIG. 14 ) and the dividing member  80 ′ when the barrel segment is fully assembled. In this manner, the saw blade  22  is fully secured for use as against unintended movement during use of the knife  30  within the respective chamber in which it is mounted. 
         [0086]    In another embodiment of the invention, as shown in  FIGS. 15 to 18 , the barrel portion  34 , may comprise a dividing member  80 ″ and two recessed receiving members  81  and  82  in contacting relation with opposite sides of the dividing member  80 ″ along its opposed inner surfaces (as best seen in  FIG. 15 ). The recessed receiving members  81  and  82  may be formed with recessed receiving portions  81   a  (as best seen in  FIG. 16) and 82   a  (as best seen in  FIG. 17 ) respectively. The recessed receiving members  81  and  82  are operable to receive therein a selected one of utility blade  21  or wallboard blade  22 . 
         [0087]    As best seen in  FIG. 16 , the recessed receiving member  81  contains a profile that corresponds substantially with the longitudinal profile of utility blade  21 , such that a first lateral shank face of the shank portion  47   a  of the utility blade  21  is received within or mates with the recessed receiving portion  81   a . Likewise, and as shown in  FIG. 17 , recessed receiving member  82  contains a profile that corresponds substantially with the longitudinal profile of wallboard blade  22 , such that a first lateral shank face of the shank portion  47   b  of the wallboard blade  22  is received within or mates with the recessed receiving portion  82   a.    
         [0088]    It is to be appreciated that the recessed receiving members  81 ,  82  may be fastened to the dividing member  80 ″ by conventional fasteners (e.g. screws, rivets, etc.), not shown. 
         [0089]    The barrel housing segments  48 ′ and  49 ′ overlay and are in contacting relation with a second lateral shank face of a selected one of utility blade  21  or wallboard blade  22 . The barrel housing segments  48 ′ and  49 ′ may provide further assistance in retaining the second lateral shank faces of each of blade  21  and blade  22 , respectively in mated held fast relation within the respective recessed receiving portions  81   a ,  82   b.    
         [0090]    To further assist in retaining the blades  21 ,  22  in the barrel portion  34 , the hand tool  30  may be provided with blade retaining assembly operable to selectively engage a selected one of the shank portions  47   a ,  47   b  against unintentional removal of the blade  21 ,  22 . In the embodiment shown in  FIG. 16 , the blade retaining assembly comprises at least one tooth  92   a ′ formed on an upper edge  81   b  of the first recessed receiving member  81  extending downward therefrom operable to engage with the shank portion  47   a  of the utility blade  21  to hold same fast with its recessed receiving portion  81 . Another tooth  92   b  may be formed on the upper portion on  33  of the barrel portion  34  extending downward therefrom, and in combination with  92   a  on the first recessed receiving member  81  hold utility blade  20  against unintentional sliding movement out of the barrel portion  34 . 
         [0091]    More particularly, as best seen in  FIG. 16 , when the conventional utility knife blade  21  is fully inserted into hand tool  30  in a rearward sliding motion into its respective chamber, each of the downwardly extending teeth  92   a ,  92   b  engages one of the respective indexing notches  25 ,  25 . The rear edge  21   a  of the utility blade  21  abuts against rear shoulder  60 ″ of the barrel portion  34  which acts as a stop means to limit rearward sliding movement of blade  21  within its respective chamber. 
         [0092]    In this fully inserted configuration, upward movement of the utility blade  21  is limited by engagement of the upper edge of the blade  21  with a bottom surface of upper portion on  33  of the barrel portion  34  (as best seen in  FIG. 16 ). In this fully inserted configuration, downward movement of the utility blade  21  is limited by engagement of the lower sharpened edge of the blade  21  with the lower straight edge  62 ″ (as best seen in  FIG. 16 ) formed on the first recessed receiving member  81 . Side-to-side movement of the utility blade  21  is limited by engagement of the first lateral shank face of the blade  21  with the recessed receiving member  81  (seen in  FIG. 16 ) and by engagement of the opposite second lateral shank face of the blade  21  with the inner surface  48   a  (as best seen in  FIG. 18 ) of the barrel housing segment  48 . In this manner, the utility blade  21  is secured as against unintended movement during use of the knife  30 , within the respective chamber in which it is mounted. 
         [0093]    Similarly, although not shown in the appended drawings, the wall board saw blade  22  may also be provided with a plurality of indexing notches  25 ,  25 . In this particular embodiment, when the wallboard saw blade  22  is fully inserted in a rearward sliding motion into its respective internal chamber, at least one of the downwardly extending teeth  92   a ,  92   b , engages one of the respective indexing notches (not shown) to securely hold the blade  22  in its respective chamber against forward sliding movement of the blade  22 . 
         [0094]    In the embodiment shown in  FIG. 17 , the blade retaining assembly comprises a fastener receiving means  79  formed through dividing member  80 ″ and operable to receive therein a fastener to retain the wallboard saw blade  22  within its respective chamber. Additionally, the shank portion  47   b  of the saw blade  22  may contain an indexing hole  29  operable to receive therethrough a fastener for securing the blade  22  to the dividing member  80 ″. 
         [0095]    Additionally, as best seen in  FIG. 17   a , the medial  22   d  and rear  22   f  trailing edges of the saw blade  22  shank portion  47   b  respectively engage with congruently shaped medial  76 ″ and rear  74 ″ shoulder surfaces, formed on the internal face of recessed receiving portion  82   a  of the recessed receiving member  82  in  FIG. 17   a , to act as stop means limiting rearward sliding movement of the blade  22  within its respective internal chamber. Similarly, an upper shoulder surface  71   a ″ and a lower shoulder surface  71   b ″ each of which are formed on the internal face of recessed receiving portion  82   a  of the recessed receiving member  82  in  FIG. 17   a , and are each respectively engageable with the upper  22   b  and lower  22   h  trailing edges of the blade body portion (which shoulder surfaces  71   a ″ and  71   b ″ mark the transition between the blade body portion and the shank portion  47   b ) to limit rearward sliding movement of the blade  22  within its respective internal chamber. 
         [0096]    In this fully inserted configuration, upward movement of the wallboard saw blade  22  is limited by engagement of the first upper straight edge  22   a , the second upper straight edge  22   c  and the medial straight edge  22   e  of the shank portion  47   b  of the blade  22  with upper straight shoulder surfaces  72   a ″,  72   b ″ and medial straight shoulder surface  72   c ″, respectively, each of which are formed on the internal face of recessed receiving portion  82   a  of the recessed receiving member  82  in  FIG. 17   a . Downward movement of the saw blade  22  is limited by engagement of the lower straight edge  22   g  of the shank portion  47   b  of the blade  22  with lower straight shoulder surface  75 ″ each of which are formed on the internal face of recessed receiving portion  82   a  of the recessed receiving member  82  in  FIG. 17   a . Side-to-side movement of the wallboard saw blade  22  is limited by engagement of one side face of the blade  22  with the internal face  49   a  of the second barrel segment  49 ′, and by engagement of the opposite other side face of the blade  22  with dividing member  80 ″. Accordingly, the thickness of the blade  22  is substantially the same as the distance between the internal face  49   a  (as best seen in  FIG. 18 ) and the dividing member  80 ″ when the barrel segment is fully assembled. In this manner, the saw blade  22  is fully secured for use as against unintended movement during use of the knife  30  within the respective chamber in which it is mounted. 
         [0097]    The barrel portion  34  further comprises a locking member  83  (as best seen in  FIGS. 7   c  and  15 ). Locking member  83  has a thumb-engagement portion  85  positioned on its side surface and a mounting bearing  84 . The locking member  83  is mounted for rotation about its mounting bearing  84  between a raised unlocked configuration (not shown) and a lowered, locked configuration (which configuration is illustrated in all assembly figures), and in which locked configuration the locking member  84  overlies an upper portion  33  of the barrel portion  34  and upper edges  48   d ,  49   d  (as best seen in  FIGS. 14 and 18 ) of the housing segments  48 ′ and  49 ′, respectively to hold the housing segments  48 ′ and  49 ′ in their closed configurations as best seen in  FIGS. 7   c  and  15 . Locking member  83  is pivoted upward to the open position by a user engaging thumb engagement member  83  and rotating same upward. 
         [0098]    A thumb rest  38  is optionally mounted in fixed relation atop the barrel portion  34  to assist the user in manipulating the knife during use. 
         [0099]    The foregoing description has been presented for the purpose of illustration and is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching and will be apparent to those skilled in the art. For example, while knife blades of two different forms and shank profiles are shown in the drawings and described in detail above, it will be appreciated that various other tool elements may be substituted therefore, including, without limitation, those tool elements known to have been previously used as a component of the well-known Swiss Army Knife™. Appropriate modification of the shank portion of such tool elements for operative fitment within a respective recess formed within the barrel portion  34  is well within routine skill of an average person skilled in the relevant tool making art, once they have fully read, digested and understood the implications of the present disclosure. Also, while only two internal chambers each having respectively different cross-sectional heights and thickness along the length of their longitudinal axis, are formed within the barrel portion  34  described above to accommodate two different tool elements having respectively different cross-sectional shank profiles, one skilled in the art will readily appreciate that the number of such internal chambers can be increased to three, four or even more, so as to accommodate an equal plurality of corresponding tool element shank profiles. Also, while the barrel portion  34  is described above as comprising two opposed housing segments  48 ,  49  that mate with dividing member  80  to form two separate internal chambers, one skilled in the art will readily appreciate that the housing segments  48 ,  49  may mate with each other along a medial plane of the barrel portion  34 , to form at least two chambers of overlapping volume that are not separated from each other by dividing member  80 .