Abstract:
An apparatus for cutting expanded fibrous and soft foam materials has a linear clamping feature with an integrated blade guide, suspended in a position to allow unobstructed travel of a cutting blade. Compression and cutting features are separated so that the cutting blade is protected from undue wear, cuts are consistent and uniform, and the apparatus is safe to use.

Description:
RELATED APPLICATIONS 
     This application is related to provisional application 61/658,183, filed on Jun. 11, 2012, and being filed within one year claims international date priority thereof. The subject matter of application 61/658,183 is hereby incorporated herein by reference in its entirety. 
     BACKGROUND 
     The industrial field of this disclosure relates to cutting devices and cutting machines and specifically to such devices and machines applicable to severing materials that are compressible or fibrous. 
     Expanded fibrous materials are used in manufacturing and construction industries for insulating or sound dampening. These materials are not easily cut with standard techniques and equipment due to the inherent difficulty of simultaneously compressing and cutting dense and or resilient expanded materials. These materials are generally cut with a hand held knife guided by a straight-edge. The knife compresses the material against a supporting surface and the knife contacts this surface during the cutting operation. This causes the knife blade to become dull so that it must be sharpened or replaced frequently. Another problem is that manual cutting does not produce consistently clean cuts and is subject to inaccuracy and variations. 
     BRIEF SUMMARY AND OBJECTIVES 
     The presently described apparatus and its method of use is directed to overcoming the drawbacks found in the prior art. The present invention consists of a linear clamping device with an integrated blade guide, both suspended in a position to allow unobstructed travel of a cutting blade. By separating the compression and cutting steps and by ensuring that the cutting blade is protected from undue wear, the present invention teaches a way to cut the aforementioned material safely and without difficulty. 
     The advantages of the present invention include, without limitation, a means of compressing expanded fibrous materials or other compressible materials such that they may be cut more easily, while, in addition, providing a cutting guide for a knife or other bladed tool and suspending an active portion of the mechanism such that the blade is prevented from wearing on or running into other objects. Generally, the present apparatus is a clamping and cutting guide wherein upright members are secured to a base or stand such that a blade of a preferred size does not touch the base or stand. A moveable compressing member may be rotated into a raised position to allow a workpiece sheet material to be placed on a support bar. The compressing member may than be lowered onto the workpiece and latched which secures a knife guide in place. An adjustable and/or elastic means provides a desired amount of clamping force applicable to a range of material thicknesses and rigidities. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an example perspective view of a cutting apparatus according to a first embodiment, and shown with a clamp arm lowered, and a cutting blade inserted within cutting guides; 
         FIG. 2  is an example top plan view thereof; 
         FIG. 3  is an example vertical section view according to cutting plane line A-A of  FIG. 2  and showing a workpiece clamped between a support bar and the clamp arm; 
         FIG. 4  is an example perspective view thereof shown with the clamp arm raised; 
         FIG. 5  is an example side elevation view of a second embodiment of the apparatus; and 
         FIG. 6  is an example perspective view thereof. 
     
    
    
     Like reference symbols in the drawing figures indicate like elements. 
     DETAILED DESCRIPTION 
     In a first embodiment, an apparatus for cutting a sheet goods workpiece  20 , has a pair of spaced apart uprights  12  and  14  as shown in  FIG. 1 , the uprights extending in a common direction nominally referred to herein as “vertical” although an alternate direction may be used. The workpiece  20  as shown in  FIGS. 3 and 4 , may be any sheet goods and in particular may be an expanded fibrous material or compressible foam or other compressible material or other types. Such material may be any type of densely packed or resilient expanded materials. The uprights  12 ,  14  may be made of a rigid material such as steel configured as shown in  FIGS. 1-4  or otherwise as suitable for cutting operations as described herein. The uprights  12 ,  14 , may be rigidly secured to a base  17  in fixed mutual positions which define a first direction between them (see arrow “A”). The base  17  may be a wooden platform, or any other support structure made of any rigid material suitable for the intended purpose as described herein. 
     A support bar  18  may be engaged with and extensive between the uprights  12  and  14 . Support bar  18  may be fabricated from square tube stock as shown in  FIGS. 1-4  and may be slotted, notched or pierced at its opposing ends as shown in  FIG. 4  for engagement with uprights  12  and  14  in a manner allowing support bar  18  to move vertically (float) on uprights  12  and  14  while maintaining engagement and a horizontal attitude. Support bar  18  may have a first elongated slot  21  ( FIG. 4 ) therein lying in the first direction “A”. 
     A clamp arm  19  may have a second elongated slot  22  therein, the clamp arm  19  pivotally engaged, using a pivot pin or other pivotal means, with one of the pair of uprights. In this embodiment, clamp arm  19  is rotatable about upright  12 ; and is therefore movable between a first position “B” placing clamp arm  19  in parallel with support bar  18  as shown in  FIG. 1 , and a second position “C” placing clamp arm  19  angularly spaced apart from support bar  18  as shown in  FIG. 4 . When clamp arm  19  is positioned in first position “B” it may be latched in place by any common latching device  12  and therefore take a fixed rigid horizontal position. A means for setting a uniform space between support bar  18  and clamp arm  19  when clamp arm  19  is in the first position “B” may include a pin-in-hole arrangement  24  as shown in  FIG. 3 . The pin-in-hole arrangement may include plural holes  25  aligned in the vertical within each of the uprights  12  and  14  and, further, an adjustment pin  16  may be engaged within a selected one of said plural holes  25  in each of the uprights. A spring  15  may be positioned between the support bar  18  and the adjustment pin  16  in each of the uprights, and such a spring  15  may be a coil spring placed about each of the uprights  12 ,  14 . 
     In a second embodiment, the apparatus for cutting a sheet goods workpiece  20 , has a pair of spaced apart uprights  32  and  36  as shown in  FIG. 5 , the uprights extending in a common direction nominally referred to herein as “vertical” although an alternate direction may be used. The uprights  32 ,  36  may be made of a rigid material such as steel configured as shown in  FIG. 5  or otherwise as suitable for cutting operations as described herein. The uprights  32 ,  36 , may be rigidly secured to a base  34  in fixed mutual positions which define a first direction (see arrow “A”). The base  34  may be a wooden platform, or any other support structure made of any rigid material suitable for the intended purpose as described herein. 
     A support bar  35  may be engaged with and extensive between the uprights  32  and  36 . Bar  35  may be fabricated from extruded angle stock of a rigid and strong metal with two separate pieces placed in mirror image positions and fixed by common hardware to uprights  32  and  36  as shown in  FIG. 5 . Support bar  35 , although being mounted in a rigid and fixed position on uprights  32  and  36  may be positionally adjusted by changing its mounted position vertically on the uprights within alternate hole sets as shown in  FIG. 5 . Support bar  35  is not able to move dynamically as with support bar  18  described in the first embodiment. Support bar  35  may have a first elongated slot  21  therein lying in the first direction “A”, said slot  21  may be the result of a longitudinal separation between the L-rods as shown. 
     A clamp arm  31  may be constructed in the same manner as with support bar  35  thereby having a second elongated slot  22  therein, the clamp arm  31  may be pivotally engaged, using a compliant member  33  such as a tension spring, an elastomeric strip, a pneumatic cylinder or similar device engaged with upright  32 ; and is therefore rotatable between a first position “B” placing clamp arm  31  in parallel with the support bar  35  as shown in  FIG. 5 , and a second position placing clamp arm  31  angularly spaced apart from support bar  35  in a similar arrangement as shown in  FIG. 4 . Upright  32  may extend through slot  22  thereby assuring that clamp arm  31  rotates in a vertical plane. When clamp arm  31  is positioned in first position “B” it may be latched in place by any common latching device but more specifically by engagement between a latching pin  37  carried on a downwardly extending portion  38  of clamp arm  31  into any one of a set of vertically aligned notches  39  in upright  36  as shown in  FIG. 5 . Therefore, clamp arm  31  is able to be fixed into a rigid, approximately horizontal attitude. 
     In both of the above described embodiments, the support bar  18  or  35  may be set at a selected position on the uprights  12 ,  14  and  32 ,  36  respectively relative to base  17  or  34 . In the first embodiment it is clear that support bar  18  may be more easily adjusted as to its height above the base  17  and its space apart from clamp arm  19 . Also, in the first embodiment, support bar  18  may be spring mounted so that with workpiece  20  lying between support bar  18  and clamp arm  19  a clamping force is applied to workpiece  20  and this force is directly related to the space between support bar  18  and clamp arm  19 , as well as the resistance against being compressed of the workpiece  20  which is a characteristic that varies with the type and thickness of workpiece  20 . With respect to the second embodiment, once set, the support bar  35  is not movable, while clamp arm  31  may be secured in a variable clamping position which changes the space between bar  35  and arm  31  and thus the clamping force on the workpiece  20 . 
     Embodiments of the subject apparatus and method have been described herein. Nevertheless, it will be understood that modifications may be made without departing from the spirit and understanding of this disclosure. Accordingly, other embodiments and approaches are within the scope of the following claims. 
     Clamp arm  19  may have a handle  10  and a clamping screw  11 . Knife  13  is shown in  FIG. 1 . Handle  30  is shown in  FIG. 5