Abstract:
Pliers-like tools having opposing and cooperating jaw elements wherein one of the jaw elements includes a heelpiece having a non-circular recess formed therein and in which a mechanical element associated with a jaw carrier portion of a handle is selectively inserted so as to be in non-movable relationship with respect to the one jaw element. Mechanical elements are provided for fastening the handle to the one jaw element at the area of the recess.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to pliers-type tools which are operatively connected to manipulate opposing jaws and more particularly to such tools having one jaw of the tool having a fixing heelpiece mounted to a support part of one handle. 
     2. Description of the Related Art 
     A number of difficulties are encountered if the jaw is to be made in one piece. On the one hand, the necessary small diameter holes cannot be punched in the jaw. On the other hand, the assembly is fragile because of the high shear stresses exerted on the rivets when the pliers are used. 
     Pliers-like tools are known and described in GB-A-2 067 451 and CH-A-685 749. These prior art devices have hole problems referred to above and are also relative bulky. 
     SUMMARY OF THE INVENTION 
     The aim of the invention is to provide pliers-like tools wherein components of the jaws thereof can be assembled in a highly economic and compact but nevertheless reliable manner. 
     To this end, the invention consists in pliers of the aforementioned type characterised in that one of the opposing jaws of the pliers includes a heelpiece having a non-circular recess therein in which a mechanical projection associated with a portion of at least one component of a tool handle is selectively inserted and wherein mechanical means are provided through the area of the recess to secure the handle portion to the heelpiece of the jaw element. 
     The pliers of the invention can have one or more of the features of claims  2  through  12 . 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Embodiments of the invention will now be described with reference to the appended drawings, in which: 
     FIG. 1 represents in perspective a jaw of adjustable pliers in accordance with the invention; 
     FIG. 2 is a plan view of this jaw to a larger scale; 
     FIG. 3 is a view of a sheet metal handle part to be assembled with the jaw in cross-section taken along the line III—III in FIG. 4; 
     FIG. 4 is a plan view of the part from FIG. 3; 
     FIG. 5 is a plan view of adjustable pliers constructed from the parts shown in FIGS. 1 and 2, on the one hand, and FIGS. 3 and 4, on the other hand; 
     FIG. 6 is an end view of the same pliers; 
     FIG. 7 is a view of the same pliers in section taken along the line VII—VII in FIG. 6; 
     FIG. 8 is a view of a detail of the pliers to a larger scale and in section taken along the line VIII—VIII in FIG. 7; 
     FIG. 9 is a partial plan view of a variant embodiment; 
     FIG. 10 is a view to a larger scale in section taken along the line X—X in FIG. 9; 
     FIG. 11 is a partial view in cross-section of a second variant embodiment; 
     FIG. 12 is a partial view in longitudinal section of a third variant embodiment; 
     FIG. 13 shows flat nose pliers in accordance with the invention; and 
     FIGS. 14 and 15 are partial views in section taken along the lines XIV and XV in FIG. 13, respectively. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1 and 2 represent a one-piece jaw  1  for adjustable pliers  2  shown in FIGS. 5 through 7. In addition to the jaw, the pliers  2  comprise a forged interior one-piece handle member  3 , a hinge pin  4  attached to the handle  3  and an exterior handle member  5  attached to the jaw  1 . The handle member  5  is made of two elongate parts  6 ,  7  symmetrical to each other about the median plane P of the pliers, which is the section plane of FIG.  7 . 
     The jaw  1 , which is called the top jaw, is symmetrical about its own median plane Q which coincides with the plane P when the pliers are assembled. The jaw comprises a thick jaw member  8  the lower active face of which has striations  9  and, to the rear of this jaw member, a plane fixing heelpiece  10 . The thickness e of the heelpiece is significantly less than the thickness E of the jaw member and is typically in the order of half the thickness E. For example, e is in the order of 4 mm and E is in the order of 9 mm. 
     The boundary between the jaw member  8  and the heelpiece  10  forms a rectilinear shoulder  11  perpendicular to the plane Q on either side of the heelpiece. There is a cut-out  12  in the heelpiece over a substantial part of its area. 
     The handle member  3  is an elongate part which constitutes, in one piece, on one side of the pin  4  the top handle  13  of the tool and on the other side of the pin  4  the bottom jaw  14  of the pliers. The top side of this jaw carries striations  15  and the jaw  14  has the same thickness E as the jaw  1 . 
     One of the two parts of the handle member  5  will now be described, namely the part  6 . 
     One end of the part  6  forms the bottom handle  16  of the tool and there is a slot  116  through an intermediate portion of the part  6 . As is usual in adjustable pliers, the slot is elongate and has undulating sides to enable the pin  4  to be put into any one of a plurality of positions along the slot. 
     In front of its intermediate portion the part  6  has a jaw-carrier portion  17  the bottom surface  18  of which is rectilinear. The portion  17  has a stamped area that forms a projection  19  on its inside face, a hole  20  punched more or less at the centre of this projection and a hole  21  punched in front of the projection. As is well known to the skilled person, a stamped area of this kind is formed by displacement of the sheet metal in translation in a direction perpendicular to its plane by a distance less than its thickness (FIG.  3 ). 
     Referring to FIGS. 2,  4 ,  5  and  7 , it can be seen that the top contour  22  of the heelpiece  10  of the jaw  1  follows that of the portion  17  and that its bottom contour  23  is slightly above the top contour of the bottom jaw  14  when the pliers are closed with the jaws in contact with each other. 
     The cut-out  12  is not circular, but broadly triangular with rounded corners, and has a rectilinear front surface  24  parallel to the shoulders  11 , an arcuate top surface  25  and a rectilinear first rear surface  26 , both parallel to the contour  22 , and a rectilinear second rear surface  27  at an acute angle, in the order of 45°, to the surface  24  and at an obtuse angle, in the order of 120°, to the surface  26 . The surfaces  26  and  24  are at a small acute angle to each other, in the order of 15°. 
     The projection  19  on the part  6  is the shape of a trapezium with rounded corners which more or less mates with the rear half of the cut-out  12 , three of its sides cooperating with the surfaces  24 ,  26  and  27  of the latter. This is shown in chain-dotted line in FIG.  2  and in continuous line in FIG.  7 . When the projection  19  is nested in the cut-out  12  in this way, the front hole  21  is in the radius between the surfaces  24  and  25  (FIG.  2 ). 
     To assemble the pliers the parts  6  and  7  are offered up facing each other on respective opposite sides of the handle  3  and the jaw  1  and the two projections  19  are inserted in the cut-out  12 . A small space remains between the two projections, as shown in FIG.  8 . This positions the heelpiece  10  perfectly parallel to its general plane relative to the parts  6  and  7  and brings each shoulder  11  into contact with the corresponding surface  18 . A spacer  28  is provided between the rear portions  16  of the parts  6  and  7  (FIG.  7 ). 
     Assembly is then completed by fitting four rivets  29 , two of which pass through corresponding holes in the portions  16  and the spacer  28 , one of which passes through the holes  20  in the two projections  19  and the last of which passes through the two holes  21  and through the cut-outs  12 . Peening this last rivet expands its shank which presses it firmly into the radius between the surfaces  24  and  25  of the cut-out  12 . 
     Finally, the hinge pine  4  of the pliers is fitted, The jaw  1  is perfectly positioned by cooperation of the projections  19  with the cut-out  12  and by cooperation of the shoulders  11  of the jaw  1  and the surfaces  18  of the parts  6  and  7 , these shoulders and these surfaces forming bearing surfaces which withstand the clamping forces. Consequently, the front rivets  29  are not loaded in shear during use of the pliers and merely hold the three parts  1 ,  6  and  7  pressed together. The holes  20  and  21  for these rivets are made in the two sheet metal parts  6 , the thickness of which is typically in the order of 2.5 mm, and can therefore be punched in these two parts with a very small diameter, for example 3 mm. This would not be possible in the heelpiece  10 , the thickness of which is in the order of 4 mm, as indicated above. 
     In the variant of FIGS. 9 and 10 the projections  19  mate with all of the cut-out  12  and two holes  20  are punched in each of the projections for the two front rivets  29  to pass through. The projections  19  can be forcibly inserted into the cut-out  12  if necessary. 
     As shown diagrammatically in FIG. 11, in another variant the heelpiece  10  is solid and has a projection  19 A on each face, and each part  6 ,  7  has a stamped area projecting outwards that forms an inside recess  12 A. Each projection  19 A mates with at least part of the contour of the corresponding recess  12 A, in the sense explained above with reference to FIGS. 1 through 10, and holes  20 ,  21  and front rivets  29  are disposed in a corresponding manner. The heelpiece includes at least one rivet hole, preferably outside the increased thickness areas  19 A. Note that in this variant, to obtain a hole or holes in the heelpiece with a diameter as small as previously the heelpiece must be machined (drilled). 
     In the FIG. 12 variant the heelpiece  10  again has a cut-out  12 , although of oblong shape, with rounded ends and a major axis more or less parallel to the top surface of the parts  6  and  7 . The latter do not have the projections  19  but include two punched holes  21  each inscribed within one of the radii at the longitudinal ends of the cut-out. The parts  1 ,  6  and  7  are simply assembled by means of two front rivets  29  through the holes  21 . When these rivets are peened their shank expands and they are therefore pressed firmly against the rounded ends of the cut-out. 
     Note that in this variant the rivets are loaded in shear. Consequently the holes  21  and the rivets have a larger diameter than in the variants previously described. 
     FIGS. 13 through 15 show an application of the invention to flat nose pliers. The pliers comprise two one-piece jaws  30  each assembled to a handle  31 . The two jaws  30  are hinged together by a fixed pin  32 . In front of the pin they form a jaw proper (or nose)  33  and they are extended beyond the pin  32  by a thinner rear fixing heelpiece  34  in one piece with them. 
     Each heelpiece has a non-circular cut-out  12  consisting in this example of a front circular arc  35  of relatively large radius, a rear circular arc  36  of relatively small radius and two tangents common to these two arcs. 
     Each heelpiece  34  locates between two sheet metal parts  37 ,  38  which together form the corresponding handle  31  and each of which has a circular stamped area  19 . The inwardly projecting stamped area  19  forms a projection that mates with the front arc  35 . A rivet  29  passes through central holes  20  in the projections  19  and another rivet  29  passes through rear holes  21  in the parts  37  and  38  inscribed within the rear arcs  36 . At the front each sheet metal part has a rectilinear edge  39  that cooperates with a rectilinear shoulder of the part  30  situated at the root of the heelpiece  34 . 
     Note that if the handle of the pliers is positioned relative to the attached part  1 ,  30  by means of a surface such as the surfaces  18  or  39  the assembly could alternatively include circular projections like the projections  19  from FIG. 13 nested in a circular recess. If the circular projections are stamped areas in sheet metal parts, the advantage is again obtained of being able to punch small diameter rivet holes. 
     It is to be understood that the invention applies equally to fixing any tool jaw to any support part, which can be made not only from sheet metal but also from plastics material, aluminium, etc.