Patent Document

RELATED APPLICATIONS 
       [0001]    This application claims the benefit of co-pending U.S. Provisional Patent Application Ser. No. 61/064,842, filed on Mar. 31, 2008, incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. The Field of the Invention 
         [0003]    This invention relates generally to hand tools, and, more particularly, to scrapers. 
         [0004]    2. The Background Art 
         [0005]    Portions of the world and of the United States of America have a combination of temperature extremes and high humidity. Temperature extremes cause cycling between evaporation of moisture and condensation of moisture during the 24 hours of the day. Likewise, with seasonal changes, weather may range from wet, snowy, icy, or the like to sunny and hot. 
         [0006]    One consequence of weather, temperature, and moisture is protection of paint and stain required to maintain wood. Periodically, paint must be removed. Meanwhile, underlying layers of previous years must typically be prepared for painting. This may involve scraping. In humid environments, it typically requires removal of layers of paint that have delaminated from the underlying wood. Various mechanisms have been used for the removal of old paint including blow torches, wire brushes, scrapers, and the like. Each approach has its benefits and difficulties. 
         [0007]    It would be an advance in the art to provide a scraper that is more effective than conventional scrapers. Whether using a putty knife or a scraper of another type, a user must apply significant downward pressure of a blade against the surface containing paint. The blade must slide along some paint at locations that maintain their integrity and do not remove. By the same token, the blade must penetrate and lift away portions of the paint adhered to the surface. Of course, some paint that is well adhered may still be stripped by a scraper. Nevertheless, it is not uncommon for a user to pass over a surface several times with a scraper blade trying to assure that the paint that should be removed has been removed. 
         [0008]    Thus, it would be an advance in the art to provide a paint scraping tool that could reduce the number of passes, and render more effective the scraping of paint. Scrapers may be used in combination with blow torches. Blow torches may help with softening or separating paint from the underlying wood by lifting it away from the surface. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    In view of the foregoing, in accordance with the invention as embodied and broadly described herein, a method and apparatus are disclosed in one embodiment of the present invention as including a scraper tool having multiple, independent, blades. So that all of them operate within the single plane they may be mounted in a frame or handle with parallel edges all acting in a plane. For example, most of the embodiments of such a tool may have two, three, or four blades. 
         [0010]    In one embodiment, the apparatus with two or more blades operates with both blades in contact simultaneously with the surface of the scraped material. In an alternative embodiment, the scraper may include many blades spaced from one another such that all of three, four, or more blades may be in contact with a surface at one time. Accordingly, a first blade edge may scrape along the surface, followed by a second blade edge shortly behind, and that of another optional blade therebehind. 
         [0011]    Thus, with the device spacing the blades apart, the user may capture by a second, third, or other subsequent blade those portions of loose paint on the surface over which previous blades passed but simply did not remove. For example, if a first blade rides up over a portion of the paint and refuses to lift the paint off the underlying wooden surface, a later blade may pass over that surface and remove it. Likewise, the blade may lift up on one side as a result of variations in surface texture, the paint thickness, or debris. Thus, further away, the blade may rise further and fail to remove paint from the surface. Following blades may still come along be, making better contact with the surface, for example, because they are independent or as a result of having less debris captured thereunder. By not riding up over the same material they may now remove it. 
         [0012]    Thus, it has been found that an apparatus and method relying on multiple, independent blades having parallel, coplanar, cutting edges are more effective then a single blade. Such an apparatus seems to perform better than multiple passes with a single blade. It has been found that multiple blades will each take paint material from the surface, and collect it in the space between the blades, discharging it out the sides, and at the end of the stroke. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The foregoing features of the present invention will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only typical embodiments of the invention and are, therefore, not to be considered limiting of its scope, the invention will be described with additional specificity and detail through use of the accompanying drawings in which: 
           [0014]      FIG. 1  is a perspective view of one embodiment of an apparatus having multiple, independent, blades having parallel, coplanar cutting edges in accordance with the invention; 
           [0015]      FIG. 2  is a perspective view of a paint scraper apparatus of  FIG. 1  illustrating the fastener portion for securement in an exploded configuration to show details; 
           [0016]      FIG. 3  is a perspective view of one embodiment of a blade assembly including three blades provided with a central aperture for mounting as well as peripheral apertures for registration on corresponding studs extending from the face of the handle holding the blade assembly; 
           [0017]      FIG. 4  is a perspective view of an alternative embodiment of a blade assembly in which each blade is identical to the other blades, and may be nested with one or more other blades, while also being reversible, thus providing durability, replaceability, and reduction of inventory parts by requiring only a single blade configuration; 
           [0018]      FIG. 5  is a perspective view of one embodiment of a scraper in accordance with the invention mounting the blade assembly of  FIG. 4  on a handle suitable for scraping the apparatus over a surface; 
           [0019]      FIG. 6  is a side-elevation view of one embodiment of a blade assembly in accordance with the invention; 
           [0020]      FIG. 7  is an alternative embodiment of a blade assembly in accordance with the invention, in which the blades are not double ended; 
           [0021]      FIG. 8  is a side elevation view of an alternative embodiment of a blade assembly corresponding to the scraper of  FIGS. 4 and 5 , and illustrating a system of aperture lobes that restrain the individual blades to operate together at a distinct spacing, while still maintaining one, two, or more blades to be accumulated together, and ye all may be identical shape and size; 
           [0022]      FIG. 9  is a bottom plan view of the blade assembly of  FIG. 6 ; 
           [0023]      FIG. 10  is a bottom plan view of the blade assembly of  FIG. 8 ; 
           [0024]      FIG. 11  is a bottom plan view of one embodiment of a scraper in accordance with the invention; 
           [0025]      FIG. 12  is a top plan view thereof; 
           [0026]      FIG. 13  is a front end elevation view thereof; 
           [0027]      FIG. 14  is a rear end elevation view thereof; 
           [0028]      FIG. 15  is a right side elevation view thereof; and 
           [0029]      FIG. 16  is a left side elevation view thereof. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0030]    It will be readily understood that the components of the present invention, as generally described and illustrated in the drawings herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the system and method of the present invention, as represented in the drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of various embodiments of the invention. The illustrated embodiments of the invention will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. 
         [0031]    Referring to  FIG. 1 , an apparatus  10  in accordance with the invention, may include a blade assembly  12  comprising one, two, three, or more blades  13  secured together. The blade assembly  12  may be made as a unitary, integrated component. In alternative embodiments, the blade assembly  12  may be made up of distinct pieces as blades  13 . In fact, the blades  13  in some embodiments may be identical to one another and interchangeable. 
         [0032]    In the illustrated embodiment the blades  13  may have active edges and inactive edges. The active edges are those at the front of the scraper and exposed to the surface being scraped. Meanwhile, the inactive edges are further back along apparatus  10  and may be simply held as replacements. 
         [0033]    A securement  14  may connect to penetrate through the blade assembly  12  to hold the blades  13  in place in the apparatus  10 . The securement  14  may pass through a handle  16  to secure the blade assembly  12  to the handle  16  held by a user. The handle  16  may include a grip  18  or grip portion  18  adapted to be grasped securely in the hand of a user. 
         [0034]    The grip  18  may be provided with knurling a soft elastomeric coating, a narrow portion and a wider portion, or multiple narrow and wide portions, or the like in order to improve over friction as the exclusive mechanism for securing a user&#39;s hand on the grip  18 . Finger rests, a central expansion of the body of the grip  18 , and the like may provide additional application of force by a user in pushing the scraper forward and backward, rendering more force available for scraping. 
         [0035]    A grip  18  may be connected to a foot  20  or foot portion  20  by a knee portion  22 . The knee may include a bend in order to place the plane of the foot  20  at an angle with respect to the plane of the grip  18 . In other embodiments, the grip  18  and foot  20  may actually be formed to extend substantially parallel to a single plane. They may even be in the same plane. 
         [0036]    In one embodiment, the foot  20  may include a toe portion  24  serving to register the blade assembly  12 , and to support it in at least one dimension. The toe  24  may serve to capture the blade assembly  12  between the heel  26  and the toe  24 . For example, the securement  14  may secure the blade assembly  12  to the foot in one direction, say for example, a nominal vertical direction, while the toe  24  and heel  26  secure the blade assembly  12  and support it in a horizontal direction orthogonal thereto. 
         [0037]    In one embodiment, the blades  13  may each include a base  28  or base portion that connects across a corner  29  to an extension  31  terminating at an edge  30 . For example, a single substrate of metal may be bent to form a base portion  28  and the extension portion  31  distinguished only by the existence of the corner  29  at which the bend is made. 
         [0038]    Meanwhile, the operating portion of the blade  32  is the edge  30  that may be sharpened by one of several means. For example, in several embodiments, the blades may be tapered such that they come to an edge, which may then be ground periodically on one or both sides in order to maintain its sharpness. Meanwhile, a tapered extension portion  31  may provide certain advantages including flexibility, a better, sharper edge  30 , and the like. 
         [0039]    Alternatively, a blade  13  may be formed with a single substrate material having a constant thickness. Accordingly, the edge  30  may be rendered sharp by grinding a chisel-like point or edge  30  that is simply a bevel. 
         [0040]    Referring to  FIG. 2  while referring generally to  FIGS. 1-16 , an apparatus  10  may include a fastener  32 , penetrating the blade assembly  12 , that connects to a retainer  34  through an aperture in the foot  20  of the apparatus  10 . A removable fastener  32  may be released by removing a threaded, keyed, twistable, or other form of retainer  34 . 
         [0041]    In the illustrated embodiment, the fastener  32  is threaded with a thread that mates with a thread inside the retainer  34 . In the illustrated embodiment the retainer  34  contains a blind hole that receives the fastener  32 . In other embodiments, the retainer  34  may have a through hole, threaded to permit use of a fastener  32  that can be of excessive length and still pass through the retainer  34 . 
         [0042]    The fastener  32  and retainer  34  may be formed to be of any of the well developed “quick-connect” types in which a single twist or even a fractional turn or a twist may apply pressure, operate a circumferential wedge, or lock in the blade assembly  12  into the foot  20 . It is contemplated that any suitable fastener may be used for the securement  14 , including clamps, screws, rivets, bayonet fittings, “T” bolts, “T” handles, and so forth as known in the art. In one embodiment, a cam lock such as is used on bicycle axles as a quick disconnect may be used to provide additional pressure holding the blade assembly  12  together and against the foot  20 . 
         [0043]    Referring to  FIG. 3 , while continuing to refer generally to  FIGS. 1-16 , the blade assembly  12  may include registers  38  or registration apertures  38  into which studs may extend from the surface of the foot  20  to maintain registration of the blades  13 . In the illustrated embodiments, four registers  38  or registration apertures  38  may be penetrated by studs extending from the foot  20  in order to maintain the blades  12  in alignment with one another. Thus, the various edges  30   a,    30   b,    30   c,    30   d,    30   e,    30   f  may always remain parallel to one another. Meanwhile, the edges  30   a - 30   c  may be active, while the edges  30   d - 30   f  may be inactive when connected to the foot  20 , and any, all, or each may be reversed, one at a time, or all together. 
         [0044]    Referring to  FIG. 4 , while continuing to refer generally to  FIGS. 1-16 , and particularly comparing with  FIG. 3 , one may note that the base  28  of each blade  13  may be a unique length or may be of the same length. For example, in the apparatus of  FIG. 3 , the individual blades  13  are nested in the assembly  12 . Accordingly, the corners  29  of each blade  13  may be unique to the size and location of the blade  13 . Meanwhile, the extensions  13  for each blade may extend a length suitable to space the edges  30  apart. 
         [0045]    In one embodiment, the three edges  30   a,    30   b,    30   c  may all operate in a single plane that is not parallel to the bases  28 . Thus, the grip  16  may be held at an angle to place the plane defined by the edges  30   a,    30   b,    30   c  to work on the surface being scraped. Thus, the edge  30   a  passes along the surface being scraped, followed by the edge  30   b,  followed by the edge  30   c.    
         [0046]    In certain embodiments, the blades  13  may be formed of a particular size, thickness, and angle  48  of the plane of the edges  30  with respect to the base  28  so that the thickness of the base  28  automatically provides the registration and height differentials between the various edges  30   a,    30   b,    30   c,  and so forth. Alternatively, spaces may be placed between the individual bases  28   a,    28   b,    28   c  in order to offset the edges  30   a,    30   b,    30   c,  respectively. 
         [0047]    In one embodiment, the aperture  40  may actually be formed with various lobes  42   a,    42   b,    42   c.  Accordingly, an offset in a horizontal plane, treating the base  28  as a horizontal plane, may provide preselected spacing between the edges  30   a,    30   b,    30   c.  For example, a base  28   a  may receive a fastener  32  through the lobe  42   c.  Meanwhile, the base  28   b  may receive a fastener through the lobe  42   b.  Meanwhile, the base  28   c  may receive the fastener through the lobe  42   a.  Thus, the various lobes  42  provide an offset and retention in place with the proper horizontal spacing between the various extensions  31  of the blades  13 . 
         [0048]    Referring to  FIG. 4 , while continuing to refer to  FIGS. 1-16 , the faces  44  of the blades  13  may be ground to provide a sharp edge  30 , as desired. In the illustrated embodiment, the individual blades  13  may be reground until the extensions  31  are so short as to be not useful anymore. Meanwhile, each of the blades  13   a,    13   b,    13   c  may be changed in position with any of the other blades  13   a,    13   b,    13   c,  or swapped end for end itself. Thus, in any particular location, six edges  30  are candidates for that particular location. One utility of this arrangement is that a leading edge  30   a  may receive more ware and damage then a trailing edge  30   b  or  30   c.  Therefore, at any appropriate time, the blade  13   b  may be substituted for either of the other two blades. Likewise, the blade  13   c  may be substituted for either of the other two blades. 
         [0049]    If a chip, crack, or other damage occurs along one edge  30 , the edges  30  that follow behind it in use may still pick up the ridge that is left by the flaw in the reading edge  30   a.  Meanwhile, any blade  13  can substitute for any other. Likewise, any blade  13  may be swapped end for end to present a new edge. Thus, a user may assure that by changing positions of the blades, and reversing them at any time, one may always present the best available and sharpest blade at the appropriate location. In fact, in some scenarios, a user may choose to maintain the last edge  30   c  as the sharpest, while permitting the first edge  30   a  to take the majority of the abuse and damage. 
         [0050]    The embodiment of  FIG. 4  may be provided with one or more registers  38  or registration apertures  38  if desired. The registration apertures  38  are optional. For example, the nose  24  and the heel  26  that form the housing that captures the blade assembly  12  may themselves provide support for a back-and-forth horizontal movement of the apparatus  10 , as well as resistance to twisting, and the like. By fitting the shape of the foot  20  to capture the blade assembly  12  precisely between the toe  24  and heel  26 , rotation of the blades  12  about the securement  14  may be precluded. 
         [0051]    In other embodiments, the aperture  20  may be a long rectangular aperture. Thus, the sides of the rectangular aperture, like the registration apertures  38 , may resist or preclude rotation. A fastener  32  may have a square shoulder or may be square along all of its length except the threaded portion, if present. In certain embodiments a rectangular fastener  32  may have steps formed in it, which themselves register the horizontal distances of the blades  13 , and specifically their bases  28 . Thus, various embodiments of an aperture  40  may be used to register the blades  13  with respect to the foot  20 . 
         [0052]    Referring to  FIG. 5 , the blade assembly  12  may be assembled with a securement  14  against the foot  20 . The assembly  12  may or may not be registered against the toe  24 , heel  26 , or both. In one embodiment, the securement  14  may cinch the blade assembly  12  at its corners  29  against the toe  24  of the foot  20 . Likewise, the heel  26  may register at the rear corners  29  of the blades  13  of the blade assembly  12 . 
         [0053]    Referring to  FIGS. 6-10 , while continuing to refer generally to  FIGS. 1-16 , a blade assembly  12  may be secured together by a fastener  32  of a securement  14 . The angle  48  may be dictated by the thickness of the base  28  of each blade  13 , or may be dictated by both the thickness of the blade  28 , and a spacer placed between one blade  28  and its adjacent blade  28 . In the apparatus of  FIG. 6 , the lower and inner most blade  13   c  may be shorter in length than the other blades  13   a,    13   b.    
         [0054]    However, in the embodiment of  FIG. 7 , the lowest blade  13   c  may be the same length as, or a length different from that of, the other blades  13   a,    13   b.  Again, the angle  48  in the embodiment of  FIG. 7  may be dictated by the thicknesses of the various blades  13 , or by spacers as well as spacing the blades  13 , and thus their respective edges  30  away from one another. 
         [0055]    Referring to  FIG. 8 , the aperture  40  may be configured to have various lobes  42   a,    42   b,    42   c  facilitating an offset in horizontal position of the various blades  13  with respect to the securement  14  as well as one another. In the illustrated embodiment, the base  28   b  in the center of the assembly  12  may receive a fastener  32  through the center lobe  42   b.  Meanwhile, the uppermost base  28   a  receives the same fastener  32  through the lobe  42   c.  Meanwhile, the lowest base  28   c  receives the fastener  32  through lobe  42   a.  Thus, the various lobes, here represented as circles that partially encroach on one another, may be configured to support registration of the bases  28  in the blade assembly  12  with a predetermined offset in the horizontal direction. 
         [0056]    Referring to  FIG. 9 , the blade assembly  12  showing the head of a fastener  32  and the registration apertures  38  reflects tapered blades having respective edges  30   a,    30   b,    30   c,  and opposite edges  30   d,    30   e,    30   f,  respectively, at their opposite ends. Meanwhile, the blades  13  are each bent at the appropriate angle at a vertex  29  or corner  29 . 
         [0057]    Referring to  FIG. 10 , the apparatus of  FIG. 8  may optionally include registration apertures  38 . As illustrated, the lobes  42   g,    42   h,    42   i  reflect the offset in the horizontal direction between the various edges  30   a,    30   b,    30   c.  Meanwhile, near the edges  30   a,    30   b,    30   c,  the corner  29  or vertex  29  is an inside corner  29 . Meanwhile, at the opposite end thereof, the corner  29  is an outside corner on the leg  13  corresponding to the edge  30   c.    
         [0058]    Referring to  FIGS. 11-17 , the relative proportions of the apparatus  10 , including the blade assembly  12  and the individual blades  13 , there includes a mechanism for securement  14 . The handle  16 , with its grip  18  and foot  20  are illustrated from the various orthogonal view points. 
         [0059]    In operation, an apparatus  10  in accordance with the invention may typically be used in a pushing motion. To a certain extent, the edges  30  traveling along a surface operate according to the laws of friction. The fundamental controlling equation for friction states that the normal (perpendicular) force applied against or between two surfaces multiplied by the frictional coefficient characteristic of the materials of those two surfaces, equals the frictional force resisting relative motion between the surfaces. Accordingly, no relationship or combination for surface area appears in the equation. 
         [0060]    Therefore, the net force applied by a user to the handle  16  controls the friction of the edges  30  together along the surface of the painted material being scraped. To the extent that one edge  30   a,  for example, receives more load than another edge  30   c,  the friction coefficient can at most act with the total normal force applied by and to the apparatus  10 . The area applied to the surface is not a relevant factor. Thus, an apparatus  10  in accordance with the invention should not increase frictional resistance for a user. Thus, no additional energy need be expended on the basis of friction. Therefore, the additional edges  30  at work costs no frictional penalty. 
         [0061]    Nevertheless, to a certain extent, the edges  30  may cut in under material and strip it away from the surface being scraped. To that extent, the force is not frictional force, but simply the shear force of the material. Accordingly, the sharpness of each edge  30  will have a direct relevance to cutting into material being scraped, while the peel strength of the material being peeled away will affect how much force is required to scrape. 
         [0062]    Surface texturing and variations in height may limit the effectiveness of a blade. As a practical matter, it has been found that the use of multiple blades  13 , and specifically of the multiple edges  30  working on a surface simultaneously, appear to have the benefit of capturing with each subsequent blade  30  portions of the underlying material that may have been missed due to a previous blade  30  riding up on debris, hard portions, or the like. 
         [0063]    For example, a rise or ridge on a surface may cause a leading blade  30  to ride up on that ridge, leaving almost nothing else scraped. In one embodiment of an apparatus  10  in accordance with the invention, the leading blade may take down a portion of that ridge, while the subsequent blades  30  take off other layers, and potentially reach the face surface. Thus, it has been found that each of the blades  13 , and each of the edges  30  will collect ahead of themselves the chips and debris scraped by that blade. It has been found that each of the blades actually contributes to the scraping. Thus, with no additional frictional penalty, the energy input goes directly to peeling the undesirable layers away from the underlying layer being prepared for repainting. 
         [0064]    Likewise, it has been found that a suitable spacing of from about ⅛ to about ¼ inch between each of the edges  30  and its adjacent edges  30  is suitable to easily clear debris therefrom. At spacings less than ⅛ inch horizontally between the edges  30 , it has been found that debris sometimes tends to collect. Likewise, the apparatus  10  may be made with blade assemblies  12  that provide greater than ¼ inch distance between the edges  30 . 
         [0065]    Wider spacing may create issues of strength, stabilization, vibrational chatter of the blades  13 , and the like. Nevertheless, wider spacings do serve. Thus, in general, between about ⅛ and ⅜ of an inch of a gap horizontally between the edges, or between the extensions  31  may be suitable. 
         [0066]    Meanwhile, an offset thickness of from about 1/16 to about ¼ inch may be used as the offset in the direction parallel to the extension  31 . Typically, the offset in the direction of the extensions  31 , or the plane thereof, may be selected according to the angle a user desires to hold the handle  16 . For example, less difference in length (the offset between the various edges  30 ) results in a more flat trajectory in the horizontal direction. Greater offset distance results in a higher angle of the handle  16  with respect to the operating plane defined by the three edges  30 . 
         [0067]    In certain embodiments of an apparatus  10  in accordance with the invention, the overall blade assembly  12  may have a total length from the outermost edges  30  of from about 2 to about 4 inches. Typically, a length of about 2½ inches has been found quite satisfactory. Meanwhile, the blades may have a width from about 1 inch to about 4 inches wide. Typically, for clapboard for houses, it has been found that a width of from about 1½ to about 3 inches is suitable. A width of approximately 2 inches has been found quite suitable. 
         [0068]    Meanwhile, the aperture  40  may be from about ¼ inch to about ½ inch diameter. In one embodiment, an aperture of about  3 / 8  inch with a lobe  42  interfering with its adjacent neighbor lobe  42  by about ⅛ inch provides about ¼ inch of horizontal offset between the edges  30  in a horizontal direction. Meanwhile, the apertures  28  or the registration apertures  38  may be circular or rectangular, or any other suitable shape. In one embodiment, the apertures may be from about ⅛ to about ½ inch. In one embodiment, approximately ½ inch has proven suitable as an outer dimension of diameter or effective diameter (side length) for a registration aperture  38 . 
         [0069]    In certain embodiments, the blades may be as thin as 1/32 inch. In other embodiments, the blades may be as thick as ⅛ inch each. If the blades are made in the embodiment of  FIG. 3 , it has been determined that a thickness of about 1/32 inch may be suitable. Nevertheless, so long as a suitable, chisel-type point is made by grinding the blades  13 , the blades  13  may be of a greater thickness. 
         [0070]    One advantage of thinner blades is flexibility, such that one blade  13  may deflect, and thus the three edges  30  may actually move out of plane with one another and provide additional scraping motion. Thus, the space between blades 13 , may suitably be set at from about ⅛ to about ⅜ inches. It has been found that more than about ⅛ inch and less than about ¼ inch is a completely suitable range in practice. 
         [0071]    In one embodiment, blades may be from between about 1/32 inch to about ⅛ inch in thickness. A thickness of between 1/32 and ⅛ inch may suitably be set at about 1/16 inch to provide for suitable stiffness and strength, with suitable flexibility. It has been found that an offset of 3/16 inch between the blades in a horizontal direction when using a blade assembly  12  comprising three 1/16-inch-thick blades has been found suitable. In certain embodiments, either the corner  29  or an opposite end lacking any edge  30  may be used as a registration location to fit against the heel  26  of the foot  20 . 
         [0072]    It has been found that the edges  30  may be offset in the plane of the extension  31  (e.g., parallel to the plane of the extension  31 ) by a distance of from about 1/16 to about ¼ inch. In one embodiment, an offset between edges of about ⅛ inch has proven quite serviceable. This provides a net angle  48  comfortable for pushing the scraper while keeping the hands above and away from the surface being scraped. 
         [0073]    In some embodiments, the widths of the blades  13  may be set at different values. For example, in certain embodiments, it has been found that for the embodiment of  FIG. 3 , the edge  30   c  may extend only ¼ inch below the base  28 . By the same token, the blade  13  closest to the foot  20  may be the shortest, or rather have the shortest extension  31 . If that extension extends only ¼ inch to the corresponding edge  30 , then the next blade in the center may extend an additional ⅛ inch further, with the final and closest to the work piece being approximately ¼ inch taller, and thus about ½ inch tall. 
         [0074]    Thus, in certain embodiments, it may be preferable to make blades  13  of various heights. In other embodiments, a combination of blade thickness and spacers may provide the difference in height, with each blade  13 , as illustrated in  FIG. 4  having exactly the same dimensions. Nevertheless, it has been found that an offset of from about 1/16 to about ¼ inch in the height of each edge  30  relative to its adjacent edges may be appropriate. About ⅛ inch has been found quite suitable in practice. 
         [0075]    The blades  13  may have different widths along the lengths of their edges  30 . Moreover, the distance between edges on a single blade may vary, according to the various angles with which each extension  31  may be fixed with respect to its base  28 . In the embodiment of  FIG. 4 , all the extensions  31  extend at the same angle with respect to the base  28 . In the embodiment of  FIG. 3 , the three extensions  31  may each have their own specific angle formed with their respective bases  28 . Thus, in one embodiment it has been found that a maximum length from one edge to an opposite on a single blade  13  may be from about 1 to about 3 inches. 
         [0076]    It has been found suitable to form a practical apparatus in which the maximum distance from one edge  32  to the opposite edge  30  of a single blade  13  may be about 2½ inches, and more specifically about 2 7/16 inch. Meanwhile, it has been found suitable to make the shortest blade  13  have a total length from one edge to an opposite edge of from about 1½ to about 2 inches, and one suitable embodiment has a total length of 1⅝ inches. 
         [0077]    The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Technology Category: 7