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BACKGROUND INFORMATION 
     Field of the Invention 
     The invention relates to a masonry block. More particularly, the invention relates to a building block having cavities for insulation. 
     Discussion of the Prior Art 
     Masonry blocks are frequently used for building walls of residential and commercial structures. In a conventional masonry block wall, the blocks are laid on bond, that is, the one block covers one half of two blocks below it, so that the vertical joint formed by adjacent blocks in one row does not align with a vertical joint similarly formed in a previous row. The blocks typically have passageways that allow reinforcement bars (hereinafter referred to as “re-bar”) to be inserted through the blocks to form a rectangular grid. For example, every four feet in the horizontal direction a re-bar is inserted in the vertical direction through the rows of block in that vertical four-foot length, and every four feet in the vertical direction a re-bar is inserted in the horizontal direction through the blocks that form that four-foot expanse. The re-bar is then tied together to form a rigid grid by filling cement grout into the cavities with the re-bar. 
     It is highly desirable these days to provide a masonry block that contains insulation material. The fact that re-bar is inserted in masonry blocks makes it difficult to easily and economically provide a masonry block with insulation. It is also difficult to secure the insulation within the block. 
     BRIEF SUMMARY OF THE INVENTION 
     The masonry block according to the invention, which includes a stretcher block, an end block, a corner block, a half block, and a corner block, has chambers or cavities for receiving insulation and re-bar. The layout of the chambers and recesses in the masonry block is such that, when the blocks are laid on bond, the re-bar may be inserted in the horizontal and vertical directions for rectangular grid reinforcement. Additional chambers with small notches are provided in the block for receiving and securing insulation material. Small notches for line pins are also provided in front and rear faces of the blocks. These blocks are used to construct a wall without the use of mortar and, when a course of blocks is put in place, conventional line pins may be inserted in these notches and a line inserted through the pins and pulled taut, thereby ensuring that the block formation is straight. A narrow chamber on the front face of the block allows electrical cables to be placed within the wall such that an electrical box may be placed flush against the wall. A wall constructed with this masonry block thus has greater strength and rigidity than a conventional masonry block wall and a greater insulation value. The wall construction is less expensive than conventional construction and has a positive environmental impact, because of a reduced amount of energy that is required to heat or cool a building constructed with the masonry block according to the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention is described with reference to the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements. The drawings are not drawn to scale. 
         FIG. 1A  is a first perspective view of a stretcher block, showing the top face, the first wall face, and the first end face. 
         FIG. 1B  is a second perspective view of the stretcher block, showing the second end face and the second wall face. 
         FIG. 1C  is a third perspective view of the stretcher block, showing the bottom face and first wall face. 
         FIG. 1D  is a fourth perspective view of the stretcher block, showing the second wall face. 
         FIG. 1E  is a fifth perspective view of the stretcher block, showing the second end face and the second wall face. 
         FIG. 1F  is a planar view of the top face of the stretcher block. 
         FIG. 1G  is a planar view of the second end face of the stretcher block with female connector. 
         FIG. 1H  is a planar view of the wall face of the stretcher block. 
         FIG. 2A  is a first perspective view of an end block, showing a first wall face, the top face, and an outer end face. 
         FIG. 2B  is a second perspective view of the end block, showing the first wall face and the inner end face. 
         FIG. 2C  is a third perspective view of the end block, showing the outer end face and the bottom face. 
         FIG. 2D  is a fourth perspective view of the end block, showing the bottom face and the inner end face. 
         FIG. 2E  is a fifth perspective view of the top plan view of the end block, showing the top face, the inner end face and the second wall face. 
         FIG. 2F  is a planar view of the end block, showing the top face. 
         FIG. 2G  is a planar view of the end block, showing the inner end face. 
         FIG. 2H  is a planar view of a wall face of the end block. 
         FIG. 3A  is a first perspective view of a corner block, showing a first wall face, a top face, and an outer end face 
         FIG. 3B  is a second perspective view of the corner block, showing the top face, the second wall face, and an inner end face. 
         FIG. 3C  is a third perspective view of the corner block, showing the bottom face and the outer end face. 
         FIG. 3D  is a fourth perspective view of the corner block, showing the bottom face, the first wall face, and the inner end face. 
         FIG. 3E  a fifth perspective view of the corner block, showing the second wall face, the top face, and the inner end face. 
         FIG. 3F  is a planar view of the corner block, showing the top face. 
         FIG. 3G  is a planar view of the corner block, showing the inner end face. 
         FIG. 3H  is a planar view of a wall face of the corner block. 
         FIG. 4A  is a first perspective view of a half block, showing a first wall face, an outer end face and a top face. 
         FIG. 4B  is a second perspective view of the half block, showing a second wall face, the top face, and the inner end face. 
         FIG. 4C  is a third perspective view of the half block, showing the bottom face, the outer end face and the first wall face. 
         FIG. 4D  is a fourth perspective view of the half block, showing the bottom face, the second wall face, and the inner end face. 
         FIG. 4E  is a fifth perspective view of the half block, showing the second wall face and the inner end face. 
         FIG. 4F  is a planar view of the half block, showing the top face. 
         FIG. 4G  is a planar view of the half block, showing the inner end face. 
         FIG. 4H  is a planar view of the half block, showing a wall face. 
         FIG. 5  is a top plan view of a wall constructed of the building block system according to the invention. 
         FIG. 6A  is a planar view of a wall constructed of the blocks according to the invention. 
         FIG. 6B  is a perspective view of two course of block laid on bond. 
         FIG. 7  is a perspective view of a spacer block. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will now be described more fully in detail with reference to the accompanying drawings, in which the preferred embodiments of the invention are shown. This invention should not, however, be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be complete and will fully convey the scope of the invention to those skilled in the art. 
     The invention is a masonry block  100  for building masonry block walls. The masonry block  100  is constructed to receive insulation material. The insulation material may be in any suitable form, for example, a rigid foam block, batting, or spray foam insulation. 
     The term “masonry block  100 ” is a general term for the block according to the invention and includes a stretcher block  120 , a half block  140 , an end block  160 , a corner block  180 , and a spacer block  190 . Incorporated into each block  100  are one or more chambers or recesses  200  for receiving insulation among other things, as well as a connector means  300  for mating adjacent blocks with each other. The general shape of the blocks  100  is rectangular, whereby the generally rectangular outer perimeter has one or more indentations, protrusions, and/or cavities on one or more of the faces of the particular block. Each block has two wall faces  102  that form opposite sides of the block and are the faces of the block that are visible on the two faces of a wall, and each block has a first end face  104  and a second end face  106 , a top face  110 , and a bottom face  112 . Elements that are functionally identical in the various blocks  120 ,  140 ,  160 ,  180 , and  190  retain the same reference designation. 
       FIGS. 1A-1H  illustrate the stretcher block  120 , whereby  FIGS. 1A-1E  are perspective views that show all six faces and  FIGS. 1F-1H  planar views of various faces of the block  120 . The wall faces  102  are mirror-reverse images of each other and, thus, one reference designation shall be used to indicate one or both of the wall faces. The connector means  300  on the stretcher block includes a male connector  302  and female connector  304 , as shown in  FIG. 1E , on each end face  104 ,  106 . When two stretcher blocks  120  are assembled adjacent to one another on a row, the male connector  302  on the first end face  104  mates with the female connector  304  on the second end face  106  of the adjacent block. 
     The  FIGS. 1A-1G  show a plurality of chambers, recesses and cavities  200 . One center chamber  202  is provided in the center portion of the block  120 , that portion that is between the bounds of the male and female connectors  302 ,  304 , on the end faces  104 ,  106 , respectively. Four inner chambers  204  are provided, two on either side of the center chamber  202  and positioned within the bounds defined by the male and female connectors  302 ,  304  on the end faces  104 ,  106  respectively. Center webs  206  separate the center chamber  202  from the inner chambers  204 . An intermediate web  208  separates the inner chambers  204  from outer chambers  210 , which are bounded by an outer web  211 . The center chamber  202  is bounded on the ends by a cavity wall  212 . The inner chambers  204  are separated from one another by inner chamber walls  214  and bounded on the ends by the cavity walls  212 . The outer chambers  210  are bounded on the ends by end faces  104 ,  106 . The cavity walls  212  also form outer recesses  220 . When the stretcher block  120  is placed adjacent to any of the other types of blocks  100 , each block  100  will have an outer recess that aligns with the outer recess  220  of the stretcher block  120 . The chambers  202 ,  204  and  210  and the recesses  220  are open passages that extend through the stretcher block  120 . Small notches  205  are provided in the upper corner of each face  104 ,  106  of the block  100 , which allow for the insertion of line pins (not shown). After a course of blocks  100  has been put in place, a line may be run through the line pins which, when drawn tight, will force the blocks into a straight alignment. Chamber notches  207  are provided inside of the center chamber  202  and the inner chambers  204  to help secure insulation inside of the chamber. The block  120  has a center front cavity  209  that, for example, provides space for the placement and running of electrical cables. 
       FIGS. 2A-2E  are perspective views of the end block  160 , which has the two wall faces  102  and the second end face  106  described above in connection with the stretcher block  120 , but the first end face is a solid outer end face  114  with a number of grooves  115 .  FIGS. 2F-2H  are planar views of the end block. A comparison of the end block  160  with the stretcher block  120  reveals that the end block  160  is very similar in construction to the stretcher block, but that the first end face  104  with the male connector  302  and female connector  304  has been replaced by the outer end face  114 . This end block  160  is used to finish off the end of a wall, as shown in  FIG. 5 . 
       FIGS. 3A-3E  are perspective views and  FIGS. 3F-3G  planar views of the corner block  180 , which is used to form a corner in a wall, as shown in  FIG. 5 . The corner block  180  has the wall faces  102 , a first end face that is now a solid wall  182 , and a second end face  184  that includes the male connector  302  and the female connector  304  with the recesses  230 . Arranged symmetrically about the centerline C L  are two large chambers  216  that are bounded by the outer webs  211 , a center web  206 , and the second end face  184 . As with the chambers in the other blocks, the large chambers  218  are open passageways through the block  180 . 
       FIGS. 4A-4F  are perspective views and  FIGS. 4G-4H  planar view of the half block  140 . This block is used as an end block, in place of the full-size end block  160 , so that the blocks  100  may be laid on bond relative to the previously laid course of blocks  100 . In other words, the half block  140  and the end block  160  are used in alternating rows at the corner, to that the joint formed by the end faces of two adjacent blocks will be over the approximate center of the block  100  in the course just below. See the half block  140  in  FIG. 5 . The construction of this half block  140  is very similar to that of the end block  160 , in that it has the wall faces  102 , the recesses  220  and cavities  212 . The center chamber  202  is now a truncated half-block chamber  203 . As with the other blocks, the chambers  203 ,  204 , and  210  are open passages through the block  140 . 
       FIG. 5  illustrates a course of a wall constructed with the building block  100  according to the invention. The course of wall starts with an end block  160 . Stretcher blocks  120  are interconnected with each other. In the embodiment shown, the wall includes a first wall and a second wall that extends at a 90-degree angle to the first wall. At the corner, a corner block  180  is used to bring the wall to the desired length and provide a finished outer face on three sides. Stretcher blocks  120  are then laid out along the second wall. In this particular course, the second wall is finished off with a half block  140 . 
       FIG. 6A  illustrates a wall constructed of the blocks  100 .  FIG. 6B  illustrates two courses of blocks  100 , one laid on top of the other. 
       FIG. 7  illustrates the spacer block  190  for filling any gaps or spaces that are created in the wall, particularly at or near the corners of the wall. The spacer block&#39;s  190  two end faces  104 ,  106 , each have a male connector  302  and a female connector  304 . Placing the spacer block  190  between, for example, a stretcher block  120  and a corner block  140  causes the male connector  302  on the first end face  104  of the spacer block  190  to mate with the female connector  304  on the second end face  106  of the adjacent block. Similarly, the female connector  304  of the spacer block  190  mates with the male connector  302  of the adjacent block. 
     The blocks  100  are made in standard sizes, but it is understood that the true size may be slightly smaller than the nominal dimension, for example, 12 inches or 10 inches, to ensure that the size of the wall is kept to specified dimensions. 
     It is understood that the embodiments described herein are merely illustrative of the present invention. Variations in the construction of the masonry block system may be contemplated by one skilled in the art without limiting the intended scope of the invention herein disclosed and as defined by the following claims.

Summary:
A masonry block having chambers and cavities that form recesses in the block such that, when the blocks are laid on bond, re-bar may be inserted in horizontal and vertical directions for rectangular grid reinforcement, and the wall may be constructed without the use of mortar. The masonry block includes a stretcher block, end block, and a half-block and each block block has recesses for receiving insulation, re-bar, and/or a line pin.