Abstract:
A bricklayer&#39;s combination level and plumb having a first I-section beam, a second I-section beam, and a connector pivotally and slidably connecting the second I-section beam to the first I-section beam wherein the second I-section is angularly displaceable up to and including a right angle relative to the first I-section beam.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention concerns combination level and plumbs, and in particular combination level and plumbs for use in the building industry. 
   2. Discussion of the Related Art 
   Building brick walls can be difficult and time consuming, since accuracy can be of paramount importance. For example, when building any substantial structure, such as a house, it is important that the walls are vertical, and/or arranged exactly in accordance with the architect&#39;s plans. Failure to do this may result in the structure becoming unstable, eventually leading to degradation of the appearance and/or safety of the building. 
   Building walls vertically has traditionally been achieved by using a “plumb line,” which is a cord suspended from its upper end, which supports a weight attached to its lower end. Gravity causes the center of gravity of the weight to lie vertically beneath the point of suspension. The line of the cord, can therefore, be used as a guide against which the wall can be built. 
   In order to build a level wall, it is necessary for each layer or “course” of bricks to be level. This has traditionally been achieved by laying a spirit level on each course and tapping the bricks to bring them into alignment with the spirit level. Spirit levels are commonplace and require no further explanation. 
   Additional guides, commonly used by the builder include tri-squares and laser-sighting apparatus. There are a number of difficulties commonly encountered with any of the aforementioned items namely: 
   (a) they are independent of one another, and it is not therefore easy to make “spot checks” on the accuracy of the alignment of say, a single brick, or the “squareness” of a corner, without having to move or re-align two or more of aids; 
   (b) transporting or carrying all the necessary aids to accurately check, for example a comer, is difficult and inconvenient; 
   (c) certain guides, such as plumb lines, are not particularly portable, and can be influenced by external factors, winds for example, thereby degrading the accuracy of the build; and 
   (d) the aforementioned guides need to be re-aligned for each stage of a build, between each course of bricks for example. 
   PRINCIPAL OBJECTS AND ADVANTAGES OF THE INVENTION 
   The principal objects and advantages of the present invention include: providing an apparatus for setting level and plumb lines that solve one or more of the aforementioned problems; providing such an apparatus for setting level and plumb lines that comprises first and second beams hingedly connected to one another by way of a connector wherein the connector is arranged to allow the second beam to slide relative to the first beam; providing such an apparatus that includes a connector comprising first and second elements that are hingedly connected to one another wherein the first and second elements are adapted for cooperative engagement with a respective first and second beam and wherein the connector is arranged to slidably engage the first beam to allow the second beam to slide relative to the first beam; and generally providing such an apparatus for setting level and plumb lines that is reliable in performance, capable of long lasting life, and particularly well adapted for the proposed usages thereof. 
   Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. 
   SUMMARY OF THE INVENTION 
   The improvements of the present invention preferably include first and second beams that are substantially rigid and straight. The beams may be manufactured of any suitable material, although a rigid plastics material or a metal may be most suited to the invention. The beams may have any suitable cross-section, although it is envisaged that I-, T- or box-sections would be most suitable for most applications. 
   The beams preferably incorporate so called “spirit tubes,” i.e., a transparent tube partially filled with a liquid, such that the orientation of the beams relative to the vertical and horizontal can be ascertained. Each beam may comprise one or more spirit tubes. Where more than one tube is provided with each beam, the tubes may be oriented at desired angles to one another. Desirable angles may be right angles or half-right angles. The spirit tube or tubes may be rotatable relative to the beam. Where the spirit tubes are rotatable relative to the beams, graduations may be provided to set desired angles relative to a datum or edge of the beam. 
   The first and second elements are conveniently referred to as body and head components. The body is slidable relative to the first beam, preferably by way of formations that engage with the profile of the first beam. The formations may be claws that partially surround the flange of a T- or I-section beam. 
   The body and head of the connector are preferably hingedly connected to one another by way of a pintle hinge. The body may have one or more wings that are arranged to retain a tongue component of the head. There may also be a pin that passes through the one or more wings and tongue. Alternatively, the wing or wings and tongue may comprise formations, a cup and cone arrangement for example, enabling the head to be “snapped” into engagement with the wings of the connector. 
   Where provided, the cup and cone arrangement may comprise a protrusion on the wing or wings and an aperture or recess formed in or on the tongue or vice-versa. 
   The head of the connector is also preferably adapted to engage the second beam. Most preferably, the head of the connector engages the end of the second beam. The head of the connector may be bifurcated in order to receive the second beam. The head may be affixed to the second beam by way of a pin, rivet or screw, etc., which passes through the head and the beam. Additionally or alternatively, the head and/or second beam may be provided with a cup and cone arrangement, whereby the second beam can be “snapped” into engagement with the head of the connector. Where provided, the cup and cone arrangement may comprise a protrusion on the head and an aperture or recess formed in or on the second beam. 
   The connector is preferably manufactured of a substantially rigid material, such as a plastics material or metal. Where the connector is manufactured of a plastics material, it is preferably injection molded. 
   The tongue is preferably adapted to prevent the second beam from hinging relative to the first beam beyond a desired angle. The desired angle is preferably a right angle. The tongue may have an arcuate edge to enable it to be rotated and/or hinged relative to the first beam. The tongue may also have a seat that engages the first beam when the second bean is oriented at a desired angle relative to the first beam. The desired angle is preferably a right angle. 

   
     BRIEF DESCRIPTION OF THE DRAWING FIGURES 
       FIG. 1  shows a perspective view of a corner of a wall during construction. 
       FIG. 2  shows a perspective view of a preferred embodiment of a combination level and plumb in accordance with the present invention. 
       FIG. 3  shows an enlarged and fragmentary, side elevational view of a preferred embodiment of the combination level and plumb of the present invention in an open position. 
       FIG. 4  shows an enlarged and fragmentary, side elevational view of a preferred embodiment of the combination level and plumb of the present invention in a folded position; 
       FIG. 5  shows an enlarged and fragmentary, cross-sectional view of the combination level and plumb of the present invention taken along line  5 — 5  of  FIG. 3 ; and 
       FIG. 6  shows an enlarged perspective view of a preferred embodiment of a connector of the combination level and plumb in accordance with the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   As required, embodiments of the present invention are disclosed herein, however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
   Turning now to  FIG. 1 , a typical wall  10  is shown during construction. The wall  10  comprises a number of bricks  12 , which are keyed to one another using mortar  14 . The wall  10  is constructed by sequentially laying bricks  12  adjacent to one another, with mortar  12  between adjacent bricks. The wall is built layer-by-layer in courses  16 ,  18  and  20  on foundations (not shown) or on the ground  22 . A corner of a wall is ideally “square,” with each face parallel to the directions F, S and V, being mutually perpendicular. 
     FIG. 2  shows a combination level and plumb  30  according to the present invention, comprising first I-section beam  32  and second I-section beam  34 . The beams  32  and  34  comprise spirit tubes  36  and  38 , which are oriented parallel to and perpendicular to the longitudinal axis of each beam  32  and  34 , respectively. The spirit tubes  36  and  38  are viewable from a variety of angles either directly or through apertures  40  cut into the beams  32  and  34 . 
   The first beam  32  and second beam  34  are hingedly connected to one another by way of a sliding connector  42 . The connector  42  enables the second beam  34  to hinge relative to the first beam  32  through a right angle, as indicated by arrow A. The connector  42  is also arranged to slide relative to the first beam  32  as indicated by arrow B. 
   In use, first beam  32  of the level and plumb  30  is aligned vertically V using the spirit tubes  38  aligned perpendicular to the longitudinal axis of the beam  32  against the wall  10 . A brick  12   a  is then laid on a layer of mortar  12  on top of the preceding course  20  of bricks  12 . The second beam  34  is then slid down to lie on top of the newly laid brick  12   a . If the level and plumb  30  is opened fully, it will conveniently provide a set of mutually perpendicular reference axes, which are parallel to the vectors V, F and S. 
   Thus, the perpendicularity and alignment of the beams  32  and  34  can be easily checked using any appropriate ones of the conveniently located spirit tubes  36  and  38 . The brick  12   a  can then be adjusted so that its edges lie parallel to the beams  32  &amp;  34 , and hence parallel to the ideal vectors V, F and S. 
   Further bricks  12  can then be added to the wall  10 , each one being checked for alignment either individually, or as a course  20 . 
     FIG. 3  of the drawings shows a close up side view of the connector  42 , which comprises a foot  44 , a pair of wings  46  and a tongue  48 . The foot  44  has claws  45  that engage flange  50  of the I-section of the first beam  32 . This arrangement enables the foot  44  to slide along the first beam  32 . 
   The foot  44  is connected to the pair of wings  46  that retain the tongue  48 . The tongue  48  pivots relative to the pair of wings  46  about a pin  52 . A leading edge  54  of the tongue  48  is arcuate about the axis of the pin  52 . This enables the second beam  34  to hinge downwardly, as indicated by arrow A. 
   The tongue  48  is bifurcated  56 , enabling it to engage the end of the second beam  34 . A retaining pin  58  passes through the bifurcated ends  56  of the tongue  48  and the second beam  34  to lock the two components  34 ,  48  together. 
   The tongue  48  also has a flange  60  with a seat  62  at an end thereof, as shown in FIG.  6 . The flange  60  prevents the second beam  34  from opening relative to the first beam  32  by more than a right angle. The seat  62  is provided to bolster the end of the flange  60  and to squarely contact the flange  50  of the first beam  32 . Also shown in  FIG. 3  are the spirit tubes  36  and  38 , which are of conventional construction. 
     FIG. 4  of the drawings is similar to  FIG. 3 , but shows an enlarged side elevational view of the connector  42  in a folded position. As can be seen, the flange  60  and seat  62  of the connector  42  is free to rotate relative to the first beam  32  by virtue of the arcuate edge  54  of the tongue  48 . The flanges  50  of the beams  32  and  34  lie adjacent and parallel to one another, and the foot  44  of the connector  42  remains free to slide relative to the first beam  32 . 
     FIG. 5  shows, in partial section, how the claws  45  of the foot  44  of the connector  42  engage with the flanges  50  of the first beam  32 . Further, it shows how the tongue  48  pivots about the pin  52 , relative to the pair of wings  46  of the connector  42 . 
   Finally,  FIG. 6  shows a perspective view of the connector  42 . For convenience, all reference numerals are equivalent to those as indicated in  FIGS. 3 ,  4  and  5  above. 
   It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown.