US2850802A - Bolt cutter - Google Patents

Description

W. F. BROSKE BOLT CUTTER Filed May 6, 1957 Sept. 9, 1958 imwwwm zw INVENTOR. \A/ILLIAM F.BRosKE 2,850,802 Patented Sept. 9, 1958 BDLT CUTTER William F. Broske, Camp Hill, Pa., assignor to AMP "Incorporated, Harrisburg, Pa.

Application May 6, 1ss7, Serial No. 657,195

Claims. (21. 30-226) This invention relates to bolt cutting devices and constitutes an improved alternative in bolt cutters over the type shown in U. S. patent to Wenger, No. 2,560,318.

The Wenger patent discloses a bolt cutting device comprising a pair of parallel plates, one of which provides a threaded aperture and the other of which provides an unthreaded oversized aperture for the bolt which is to be cut or sheared. In operation, the bolt is threaded through the threaded aperture until the end which is to be removed extends beyond and through the unthreaded aperture in the second one of the plates. At least one of the plates is then moved relative to the other and in a parallel plane to bring the end of the bolt against the edges of the unthreaded aperture. This movement of the plates results in a shearing of the end of the bolt and produces a clean fracture without damage to the threads at the end of bolt in the vicinity of the fracture. One of the principal advantages of the Wenger type bolt cutter is that a clean fracture is produced and the threads of ,the bolt are not damaged or deformed.

In the past, tools in accordance with the Wenger patent have been manufactured by drilling the holes for the threaded apertures (where more than one bolt size is accommodated on the single tool) and then tapping the holes to the desired thread standards for the bolts. Furthermore, it is usually, if not always, necessary to harden the plate having the threaded apertures therein since the material from which the plate is made must be relatively machineable during the drilling and tapping operations but must be relatively hard and tough if it is to withstand prolonged usage. It can be readily perceived that these operations of drilling, tapping, and heat treating of each tool as it is produced are relatively time consuming and expensive and tend to inflate the cost of any tool incorporating the Wenger invention to an unduly high level. This is particularly true since it is usually desirable in a tool incorporating the Wenger invention to provide a number of threaded apertures to accommodate several of the more common sizes of bolts which are encountered in use and, of course, for each bolt a separate drilling and tapping operation is required.

An object of the present invention is to provide an improved bolt cutting device which is reliable and sturdy and which can be manufactured in a simple and inexpensive manner. A more specific object is to provide a bolt cutter which can be manufactured without the necessity of drilling and tapping operations for each bolt size which is to be provided for. A further object is to provide a bolt cutting device incorporating parts which can be manufactured from sheet or thin plate material by conventional punch press operations. Further objects and attainments of the invention will be apparent from the description which follows and from the annexed drawings in which:

Figure l is a frontal view, with the front plate removed, of a preferred embodiment of the invention;

Figure 2 is a view similar to Figure 1 but showing the parts in a different relationship relative to each other; and

Figure 3 is a side view with parts broken away, taken in the direction of the arrows 3-3 of Figure 2 and showing a bolt in position for shearing.

In my preferred embodiment of the invention I provide a pair of plates 2, 4 having handle portions 3, 5 integral therewith and extending from their lower ends as viewed in Figure 2. These plates are maintained in spaced apart relationship by spacer 6 and by fasteners such as rivets 8 which extend through each of the plates and through the spacer 6. An additional spacer 10 is provided between the plates at the top portions thereof and additional rivets or other fasteners 12 secure the plates in their spaced apart relationship through this top spacer.

Interposed between the pair of plates 2, 4 is a slidable plate 14 having a central opening 16 of generally rectangular shape but having notches 18 cut out from the ends thereof. These notches are of a width slightly greater than the width of spacer 6 to permit entry of the spacer into the notches during sliding movement of plate 14 relative to fixed plates 2, 4. The height of opening 16 is preferably slightly less than the height of spacer 6 as shown by the drawing, and the edges of opening 16 are spaced from the edges of spacer 6. A plurality of nuts 20 having threaded apertures 22 adapted to accommodate a range of bolt sizes are loosely positioned between the edges of opening 16 and the edges of spacer 6. These nuts may be of standard type in all respects excepting that they advantageously should have parallel flat faces rather than curved surfaces on one face as is common in some types of standard nuts. Substantially flat, parallel faces can be produced by grinding nuts 20 but it is not essential that this be done. If the faces of the nuts are slightly dished (as is often the case where they are produced by a punch press), they can be accommodated in the type of tool shown in Figure 1 since it is not essential that the nuts fit snuglybetween plates 2, 4. Opening 16 is so dimensioned relative to the size of the nuts that they fit within the space between the edges of spacer 6 and the edges of opening 20 as shown, although the fit need not be tight and it is not necessary to secure the nuts in place, as shown in Figure l, by welding or otherwise. Preferably and in the disclosed embodiment, square nuts are employed in the invention although it will be apparent that nuts of other shapes can be used if the marginal portions of opening 16 conform sufficiently to the edges and the peripheries of the nuts to retain them in position.

Plate 2 provides a plurality of apertures 24, the centers of which are spaced from each other by approximately the same amount as the centers of threaded apertures 22 in nuts 29. The aperture in plate 2 for each nut is slightly oversized relative to the threaded aperture in the nut so that a bolt threaded through the nut can extend freely through its proper one of the apertures 24. The other one of the plates 4 is slotted as indicated at 23 to permit access to the faces of nuts 20 from the front of the tool as viewed in Figure 2. Slots 23- are somewhat narrower than nuts 20 so that the longitudinal edges of these slots extend over the marginal portions of the nuts to retain them between plates 2, 4 and within opening 16 of plate 14. These slots should also be of sufficient length to permit movement of any of the nuts for a distance sufficient to effect shearing at the interface of the nuts and plate 4. This-is illustrated in Figure 2 by the uppermost one of the nuts which shows the threaded apertures of the nuts in nonaligned position relative to the openings 24 of plate 2 but the threaded apertures do not extend beneath the surface of plate 4.

Force multiplying means are provided for causing sliding movement of plate 14 relative to fixed plates 2, 4 and in the disclosed embodiment this force multiplying means takes the form of a cam 25 on the end of a lever having a handle 26 which is pivoted as at 28 to fixed plates 2, 4. The arrangement is, of course, such that upon movement of the handle portion 26 of the lever towards handles 3, 4, plate 14 is moved relatively upwardly in Figure l to theposition of Figure 2. When the handles are moved away from each other, plate 14 is returned to its initial position by virtue of the extension 27 of plate 14 which bears against the end portion of the cam 25.

It is desirable under some circumstances to provide additional guide means and stop means for plate 14 and in my preferred embodiment this additional guide means takes the form of an extension 29 of plate 14 which fits within a cut out section 31 of top spacer 10. In the disclosed embodiment, sliding plate 14 also functions as a crimping die for electrical terminals and to this end provides a die surface 30 adapted to cooperate with a corre sponding die surface 32 on fixed spacer 10.

In use, handle 26 is manipulated to position sliding plate 14 such that the threaded apertures of nuts 20 are in aligned relationship to the oversized apertures 22 in plate 2. Thereafter, the bolt which is to be cut is threaded through the appropriate one of the nuts 29 until the end which is to be removed extends through the appropriate aperture 24 as shown in Figure 3. The handles are then closed and the bolt is sheared at the plane of the interface of fixed plate 2 and sliding plate 14.

Several advantages of the invention will be apparent from an inspection of the drawing and particularly from a consideration of some of the features which permit economical and rapid manufacture. For example, many of the parts can be manufactured by inexpensive punch press operations from an ordinary carbon steel plate or sheet (e. g., of about 0.083 inch in thickness). The nuts 20 can be of an ordinary commercially available type and are of course extremely inexpensive, particularly if their cost is compared with the manufacturing cost involved in a drilling and tapping operation as required in the previously known Wenger invention. These nuts can be hardened as by carburizing, nitriding or by any suitable similar process, and this operation can be carried out with ease on the nuts which are extremely small and are highly responsive to a case hardening operation. It will be apparent from the drawing that the construction of the tool is such that extremely close dimensional tolerances are not needed. This fact ic of importance since it permits the use of parts formed by stamping or other metal forming techniques which are inexpensive but not dimensionally precise. A further point is that assembly of the component parts of the tool is an extremely simple operation and the final assembly need only be riveted to l secure the parts together.

While I have disclosed a preferred embodiment of my invention, obvious modifications thereof will occur to those skilled in the art to which it appertains.

I claim:

1. A bolt cutter comprising a pair of plates slidable over each other, an opening in one of said plates and a nut positioned within said opening co-planar with said one plate, said opening in said one plate conforming to the outline of said not thereby to prevent substantial movement of said nut relative to said one plate, a boltreceiving aperture in the second one of said plates which is oversize relative to the threaded aperture of said nut, said bolt-receiving aperture and said threaded aperture being relatively movable from an axially aligned to an axially nonaligned position as said plates are moved relatively to each other, whereby a bolt threaded through said threaded opening and having end portions extending through said bolt-receiving aperture is sheared at the plane of the interface of said plates.

2. A bolt cutter comprising a pair of plates slidable over each other, an opening in one of said plates and a plurality of nuts positioned within said opening co-planar with said one plate, said nuts substantially filling said opening thereby to prevent substantial movement of any of said nuts relative to said one plate, a plurality of bolt-receiving apertures in the other of said plates, each of said nuts being movable from an axially aligned position relative to one of said apertures to an axially nonaligned position as said plates are moved relatively over each other, whereby a bolt threaded through one of said nuts and having an end extending through one of said bolt-receiving apertures is sheared in the plane of the interface of said plates.

3. A bolt cutter as set forth in claim 2 including means for retaining said nuts within said opening.

4. A bolt cutter comprising, a pair of plates secured to each other in spaced-apart relationship, a third plate slidably positioned between said spaced-apart plates, an opening in said third plate and a plurality of nuts positioned within said opening, said nuts each incorporating a threaded aperture and substantially filling said opening thereby to prevent substantial movement of said nuts relative to said third plate within said opening, a plurality of bolt receiving apertures in a first one of said spacedapart plates, and slot means in the second one of said plates aligned with said opening and with said bolt-receiving apertures, marginal portions of said slots extending over edge portions of said nuts to retain said nuts between said plates, said third plate being slidable from a position in which said threaded apertures of said nuts are aligned with said bolt-receiving apertures to a position where the threaded apertures in the nuts are not aligned with said bolt-receiving apertures whereby, upon threading a bolt through one of said nuts and upon moving said third plate relative to said pair of spaced-apart plates, the end portion of said bolt is sheared.

5. A bolt cutter comprising a pair of plates secured to each other in parallel, spaced-apart relationship, a guide member positioned between said plates, '21 third p ate slidably interposed between said pair of plates and providing an opening in surrounding relationship to said guide mem her, said guide member functioning to limit movement of said third plate relative to said pair of plates, edge portions of said opening being parallel to and spaced from edge portions of said guide member, a plurality of nuts disposed eoplanar with said third plate between said edge portions of said guide member and edge portions of said opening, one of said pair of plates providing slot means providing access to the threaded apertures of said nuts, the marginal portions of said nuts extending beyond the edges of said slot means whereby said nuts are retained between said plates, a plurality of bolt-receiving apertures in the other one of said plates, the threaded openings of said nuts being alignable with said bolt-receiving openings whereby, upon inserting a bolt through said slot means and threading said bolt through one of said nuts a distance such that its curl extends through one of said bolt receiving Openings, and upon sliding of said third plate, said bolt is sheared at the interface of said third plate and the said other one of said plates.

No references cited.

Images