Abstract:
A ruler for craft applications has an efficient construction which employs a pair of tearing edges to facilitate tearing and a pair of measurement scales. The tearing ruler may be angularly oriented to facilitate either tearing or measurement activities. The tearing edges are defined by various waveform patterns. The tearing edges may be interchangeable.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     This invention relates generally to rulers adapted for use in various craft applications. More particularly, the present invention relates to rulers which have a measurement scale as well as an extended non-linear tearing edge.  
         [0002]     A number of rulers and devices have been developed to accomplish the multiple functions of providing a measuring scale as well as a tearing edge to facilitate the tearing of paper in a non-linear pattern such as to form a deckle edge. In certain crafts such as, for example, the customization of scrapbooks, it is highly desired to form non-linear edges. Such edge configurations which may have highly irregular shapes referred to herein as waveforms. These edges present the appearance of a handcrafted, non-linear, quasi-random type edging. Some known devices employ opposite edges having a peripheral profile of different configurations and also include linear measuring scales.  
       SUMMARY OF THE INVENTION  
       [0003]     Briefly stated, the invention in a preferred form is a ruler for craft applications which comprises an elongated multi-sided body having a pair of longitudinally extending transversely spaced tearing edges. A longitudinally extending upright extension defines opposing convergent sides and terminates in a vertex substantially equiangularly spaced from the tearing edges. A measuring scale is disposed on at least one of said sides. The tearing edges are defined by waveforms which are preferably different. A measuring scale is disposed on each of the sides. The extension has a spade-like shaped profile and a pair of longitudinal indentations are defined at opposed locations of the body.  
         [0004]     The tearing edges may be formed on interchangeable members. An attachment member which defines one or both of the tearing edges is removably mounted to the base. The attachment member may be slidably received by the base and secured in a tongue and groove relationship. Alternatively, an attachment member which provides for interchangeable tearing edges has a plurality of lugs which snap into corresponding apertures of the base.  
         [0005]     An object of the invention is to provide a new and improved ruler or measuring device which also includes a pair of non-linear tearing edges.  
         [0006]     Another object of the invention is to provide a new and improved tearing ruler which may be efficiently and effectively used to provide an accurate measuring scale as well as a very efficient tearing edge.  
         [0007]     Other objects and advantages of the invention will become apparent from the detailed description and the drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]      FIG. 1  is a perspective view of a tearing ruler in accordance with the present invention;  
         [0009]      FIG. 2  is a side view of the tearing ruler of  FIG. 1 ;  
         [0010]      FIG. 3  is an enlarged sectional view of the tearing ruler of  FIG. 1  taken along the line  3 - 3  thereof;  
         [0011]      FIGS. 4A, 4B  and  4 C are top plan views of various embodiments of a tearing ruler in accordance with the present invention;  
         [0012]      FIG. 5  is an end view illustrating the tearing ruler of  FIG. 1  on a paper surface preparatory to tearing the paper;  
         [0013]      FIG. 6  is an enlarged schematic view illustrating how the ruler of  FIG. 1  may be efficiently grasped and employed for tearing purposes;  
         [0014]      FIG. 7  is an end view of the ruler of  FIG. 1  at a preferred measuring angular orientation on a surface illustrating how the ruler may be effectively employed for measuring purposes;  
         [0015]      FIG. 8  is an enlarged fragmentary top view of a tearing ruler in accordance with the present invention;  
         [0016]      FIGS. 9A, 9B  and  9 C are fragmentary perspective views illustrating alternative embodiments of a tearing ruler with interchangeable blades in accordance with the present invention, wherein  FIG. 9A  illustrates the main body of the ruler,  FIG. 9B  illustrates a double-sided tearing blade attachment and  FIG. 9C  illustrates a single tearing blade attachment; and  
         [0017]      FIGS. 10A, 10B  and  10 C are fragmentary perspective views illustrating additional embodiments of a tearing ruler with interchangeable blades, wherein  FIG. 10A  illustrates the main body of the ruler,  FIG. 10B  illustrates a single-sided tearing blade attachment and  FIG. 10C  illustrates a double sided tearing blade attachment. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]     With reference to the drawings, wherein like numerals represent like parts throughout the several views, a tearing ruler in accordance with the present invention is generally designated by the numeral  10 . The tearing ruler is a multi-function device which includes a pair of tearing edges and a pair of measuring scales as will be described below. The tearing ruler has numerous applications in connection with well known crafting activities such as scrapbook making.  
         [0019]     The tearing ruler  10  in a preferred embodiment includes an elongated body  20  which may be one foot in length or other suitable length and is in one embodiment manufactured from plastic material. In a preferred form, the ruler is a hollow member having a substantially uniform thickness, although the ruler may also have a solid configuration. The ruler may also be manufactured from aluminum, titanium or other suitable materials.  
         [0020]     The ruler  10  may best be appreciated by reference to  FIG. 3  which illustrates the multi-sided geometry principally defined by a base  21  having opposed tearing edges  22  and  24  and an upright, shoulder-like extension  30  which has a spade-like profile and converges to a vertex point  32 .  
         [0021]     Each of the tearing edges  22  and  24  are respectively peripherally defined by longitudinally extending waveform patterns  26  and  28 , respectively. The waveform patterns are preferably non-identical, non-linear and irregular in nature. In some embodiments, the patterns are configured to produce a deckle edge. The tearing edges may assume a wide variety of forms such as the waveform patterns  26 A,  26 B,  26 C,  28 A,  28 B, and  28 C illustrated in  FIGS. 4A-4C  and waveform patterns  26 D and  28 D of  FIG. 8  wherein one pattern has more closely spaced inward tear segments and the other pattern has a more gradual tear contoured pattern. Naturally, various patterns of a number of wide variety of forms such as sharply jagged, zig-zag and repeating and non-repeating, non-linear patterns, all of which are referred to as waveforms, may be employed.  
         [0022]     With reference to  FIG. 3 , the underside of the ruler base  21  adjacent each of the tearing surfaces is defined by longitudinally extending panel sides  51  and  52  and  53  and  54  which converge at substantially 30° angles. The tearing edges  22 ,  24  in preferred embodiments integrally extend from the converging vertex-like locations. Sides  51  and  53  have uniform widths, are coplanar and are medially connected by an arcuate longitudinally extending channel portion  50  to form a stable support base. In addition, longitudinally extending, transversely spaced recesses  56  and  58  traverse the sides  51  and  53  to provide a non-slip underside surface for the bases.  
         [0023]     The shoulder extension  30  has an axially symmetric spade-like shape. The extension  30  integrally extends from the oblique sides  52  and  54  to upwardly terminate at vertex  32  via convergent sides  42  and  44  which have a substantially linear planar portion. In a preferred form, panel side  42  is affixed with an English measurement scale  46  and the panel side  44  is affixed with a metric measurement scale  48 . The indicia graduations preferably extend toward the vertex point  32  as best illustrated in  FIG. 8 . The scales preferably have a central  0  and form a zero centering scale.  
         [0024]     As best illustrated in  FIGS. 5 and 6 , for tearing or tearing applications, the ruler rests against the surface of the paper  12  to be torn so that the coplanar base sides  51  and  53  engage the top surface of the paper  12 . The paper may be easily cut or torn by manually pressing down through the extension as illustrated in  FIG. 6  and upwardly pulling the paper to sever a portion of same along the selected tearing edge.  
         [0025]     The ruler  10  may also be efficiently used as a measuring scale by positioning the measuring scale ( 46  in  FIG. 7  illustration) not to be used against the surface of the paper or other material so that the tearing edge rests in the stable configuration illustrated in  FIG. 7 . In this fashion, the selected measuring scale  48  may be quite closely positioned along the paper and a precise measurement can be readily accomplished.  
         [0026]     In some embodiments such as illustrated in  FIGS. 2 and 8 , several parallel ribs  60  traverse the longitudinal extent of the ruler to facilitate the gripping and use of the ruler for tearing purposes.  
         [0027]     In addition, a pair of indentations  70  and  72  at opposing sides of the extension adjacent sides  52  and  54  respectively are provided to facilitate the grasping and use of the ruler with the fingers.  
         [0028]     With reference to  FIGS. 9A, 9B  and  9 C, a tearing ruler which employs interchangeable tearing blades is generally designated by the numeral  100 . The ruler  100  is similar in form and function to the previously described tearing ruler  10 , except for the base/tearing edge features. The base portion  120  includes at transversely opposite edge portions longitudinally extending blade slots  121  and  123 . A double-sided interchangeable blade attachment  110  is adapted to slidably mount onto the main body. The attachment  110  includes a pair of opposed, inwardly protruding tracks  122  and  124  which mate with the respective blade slots  121  and  123  in a tongue and groove fashion. The attachment  110  includes transversely spaced tearing edge patterns in the form of waveforms  126  and  128  which may be similar in form and function to the tearing edge waveforms  26  and  28 , as previously described. The interchangeable blade attachment  110  has a length commensurate with the length of the ruler body. Alternatively, the interchangeable tearing edges may each be provided by means of a single sided blade attachment  140  having a single tearing edge  141  and having a single track  142  which mounts into the blade slot  123  as illustrated in  FIG. 9C .  
         [0029]      FIGS. 10A, 10B  and  10 C illustrate another embodiment of a tearing ruler with interchangeable tearing blades which is designated generally by the numeral  200 . The tearing ruler  200  includes a plurality of longitudinally spaced apertures  202 ,  204 ,  206 , etc., in the bottom base portion of the body  220 . A single sided blade attachment  210  includes projecting lugs  212 ,  214 ,  216  which align and snap into the corresponding apertures to secure the blade attachment  210  to the main body  220 . The blade attachment peripherally defines a waveform pattern  226  which may be similar in form and function as those previously described. Alternatively, as illustrated in  FIG. 10C , a double-edged snap-type blade attachment  240  includes opposing tearing edges defined by various waveform patterns  226  and  228 . Transversely spaced strips of longitudinally spaced lugs snap into respective apertures at the underside of the main body.  
         [0030]     Multiple interchangeable attachments which incorporate various tearing edge configurations are provided in addition to the attachments  110 ,  140 ,  210  and  240 . It should be appreciated that the tearing rulers  100  and  200  provide a means wherein a single ruler body may be employed with multiple interchangeable blades so that if a different tearing pattern is desired, the tearing edge or edges may be removed and selectively replaced by a suitable tearing blade.  
         [0031]     While preferred embodiments of the foregoing invention have been set forth for purposes of illustration, the foregoing description should not be deemed a limitation of the invention herein. Accordingly, various modifications, adaptations and alternatives may occur to one skilled in the art without departing from the spirit and scope of the present invention.