A novel trowel for use by bricklayers comprised of a flat blade having a first face and an opposing second face and containing at least one protrusion on one face.

FIELD OF THE INVENTION 
       [0001]    The present invention relates to a novel trowel for use by bricklayers. The trowel comprises a flat blade having a first face and an opposing second face and containing at least one protrusion on one face. 
       BACKGROUND OF THE INVENTION 
       [0002]    Bricklayer's trowels are used in the building trade for applying and spreading mortar. Such trowels are employed to apply and spread mortar on horizontal layers or courses of bricks before the bricks of the next higher course are laid. The thickness of mortar between courses is regulated by horizontal cords and/or by the skill and experience of the bricklayer. Bricklayers sometimes use trowels for cutting or chopping bricks. 
         [0003]    A problem encountered in bricklaying is that there is no straightforward means or method of regulating the amount of mortar in the gap or cross joint between the adjacent vertical faces of adjacent bricks in the same course. As a result, a course of bricks could be longer or shorter than the desired length. The present invention is intended to address this problem. 
         [0004]    The present invention provides a bricklayer's trowel having the features recited in claim  1  of the set of claims following this description. Optional and/or preferred features of the trowel are the subject of other claims in the said set of claims. 
       SUMMARY OF THE INVENTION 
       [0005]    In accordance with the present invention there is provided a trowel comprised of a substantially flat quadrilateral blade having four corners and having a first face and an opposing second face and having a handle at one corner, the blade having at least one protrusion on one face of the blade in the region of another corner of the blade. 
         [0006]    In a preferred embodiment the trowel also contains a handle at one of its corners. 
         [0007]    In another preferred embodiment each protrusion is a substantially smoothly curved surface. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0008]      FIG. 1  hereof is a plan view of part of a trowel of the invention. 
           [0009]      FIG. 2  hereof is side elevation of the trowel of  FIG. 1 . 
           [0010]      FIG. 3  is a plan view of another trowel according to the invention. 
           [0011]      FIG. 4  hereof is a plan view of another trowel according to the invention. 
           [0012]      FIG. 5  hereof is a a perspective view of the trowel of  FIG. 4  hereof 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0013]    The present invention provides a novel bricklayer's trowel capable of better regulation of the gap or cross joint between adjacent vertical faces of adjacent bricks in the same course of bricks. The result being that the resulting course of bricks will be of the desired length compared with use of conventional trowels. 
         [0014]    Turning now to the figures hereof, the trowel  10  of  FIGS. 1 and 2  comprises a flat quadrilateral blade  11  having four corners (or “shoulders”) and a shaft, ferrule or tube  12  for receiving a handle  12   a.  The blade  11  preferably has two corners or shoulders  13 ,  14  adjacent to the end where handle  12   a  is located. Adjacent to one corner  13 , there is provided, or formed, a protrusion  15  which projects from the flat (main or top) surface of blade  11 . Protrusion  15  is preferably in the vicinity of corner  13  (e.g., 5 to 12 mm from the corner, preferably 10 mm or thereabouts for a blade having an overall length of about 20 to 30 cm and a width of about 70 mm to about 110 mm) and preferably on or near to the edge of blade  11  between handle  12   a  and corner  13 . 
         [0015]    The protrusion  15  may be on a notional line (not shown) joining corners  13  and  14 . In some preferred embodiments, protrusion  15  is at a location on blade  11  that is slightly displaced from this notional line so as to be closer to handle  12   a.  This displacement leaves the adjacent corner  13  substantially unaffected by the presence of protrusion  15  so that it can be employed for cutting bricks in the well-known manner. 
         [0016]    Protrusion  15  may be an integral or unitary part of the blade or it may be a separate part which is secured to blade  11  by any suitable means. Thus, protrusion  15  may be a dimple which is integral with blade  11  and formed by pressing or stamping. Alternatively, protrusion  15  may be a separate member secured to the blade, e.g., by spot welding. A suitable separate member (not shown) might be, e.g., a piece of metal resembling the domed head of a dome-headed bolt. 
         [0017]    Protrusion  15  is preferably of a substantially smoothly-curved dome-like form and may will preferably have a substantially circular base, as depicted in the figures hereof, since this will be easier to clean than a protrusion having sharp angles. A smoothly-curved domed protrusion can be made by stamping or pressing blade  11 . Alternatively, the blade may be formed from suitable sheet metal having a ridged section at or adjacent to the edge of blade  11  which is subjected to a grinding process to form a desired protrusion  15 . Another form (not shown) of the protrusion is cylindrical with a flat outer face. This latter form can be made by welding or spot-welding a cylindrical disc (e.g., a stud or boss) to the face of the blade. 
         [0018]    Although the present invention is not limited to exact dimensions of instant trowel there are preferred dimensions. For example, it is preferred that the total distance between the free end of the protrusion and the lower or bottom face (as shown) of blade  11  be equal to (or approximately equal to) the desired gap for mortar between adjacent vertical faces of adjacent bricks in the same course. In UK, this distance is typically 10 mm. In USA, this distance is ¼ inch (6.35 cm). Thus for UK use, blade  11  will preferably have a thickness of about 2 mm, protrusion  15  should preferably extend about 8 mm from the surface of the blade  11  from which it protrudes. However, blade  11  may have a thickness in the range of about 1 to 3 mm, and protrusion  15  would then extend a distance in the range of about 9 to 7 mm so that the total thickness of the blade and protrusion will preferably be about 10 mm if the desired gap between adjacent bricks in the same course is about 10 mm. 
         [0019]    In use, trowel  10  is employed to apply and spread mortar on bricks. When bricks are being laid, bricks are laid in a bed of mortar to form a horizontal course. As each additional brick is added to the course, mortar is applied by the trowel to the vertical face of the last-laid brick of the course. The corner region  13  of trowel  10  of the present invention is located in the vertical gap between adjacent bricks where it serves as a gauge or spacer, wherein one brick abuts a face of the trowel's blade and the adjacent brick abuts the “top” or free, distal, end of protrusion remote from the main face of blade  11 . Thus, the gap or space between adjacent bricks in a course is relatively accurately defined. When adjacent bricks in a course are thus disposed with a gap of the desired size between them, corner region  13  of the trowel is withdrawn from the gap and the gap is filled with mortar to complete the joint. The gaps between bricks in each course can therefore be of substantially uniform dimensions, substantially equal to the thickness of the blade plus the “height” of the protrusion. As a result, each course laid by the method described has substantially the desired length. It has not previously been possible to ensure readily that the gaps or cross-joints between bricks in a course were uniform by use of conventional trowels. The trowel of the present invention enables this difficulty to be surmounted. 
         [0020]    The trowel of  FIG. 1  hereof is shown with protrusion  15  near one corner or shoulder  13  of blade  11 .  FIG. 3  hereof shows a trowel of the present invention in which protrusion  15  is near the opposite corner or shoulder  14 . All the matters mentioned regarding protrusions  15  of  FIG. 1  hereof apply equally to the protrusions  15  of  FIG. 3  hereof. The side elevation of the trowel of  FIG. 3  is the same as shown in  FIG. 2  hereof. The trowel of  FIG. 3  hereof could be suited to a left-handed bricklayer, and the trowel of  FIG. 1  hereof could be suited to a right-handed bricklayer. 
         [0021]      FIG. 4  hereof shows a trowel having two protrusions  15 , one near one corner  13  and the other near opposite corner  14 . The trowel of  FIG. 4  hereof could be suited to bricklayers who are either right handed or left handed. The side elevation of the trowel of  FIG. 4  hereof is the same as  FIG. 2  hereof. All the matters mentioned regarding the protrusions  15  of  FIGS. 1 and 3  apply equally to the protrusions  15  of  FIG. 4  hereof. The trowels of  FIGS. 3 ,  4  and  5  are used to set the gap between adjacent bricks in a horizontal course in the same way as the trowel of  FIG. 1  hereof. 
         [0022]    At least one protrusion  15 , preferably all, are preferably located on blade  11  slightly offset from its respective corner(s)  13  or  14  in a direction towards handle  12   a,  so that the corner(s)  13 ,  14  can be used for cutting bricks in the well-known manner. The offset distance from the respective comer(s) will preferably be in the range of about 2 to about 20 mm, e.g. about 3 to about 15 mm, for example about 4 to about 12 mm, suitably about 5 to about 10 mm, so that the corner(s)  13 ,  14  are available for cutting bricks despite the provision of the protrusion(s)  15 . 
         [0023]    Features of one embodiment described herein may be employed in any feasible combination with features of another embodiment.