Abstract:
The present invention is a floor grinder assembly for grinding a floor. The assembly includes first and second rails configured for being mounted spaced apart from and parallel to one another. A plurality of stands is configured for mounting the first and second rails above the floor. The stands have an adjustable length for adjusting a height position of the first and second rails such that the rails define a plane above the floor. A truss is configured to mount between the rails and to be movable along a length of the rails. A grinding assembly includes a grinding wheel and a motor driving the grinding wheel. The grinding assembly is configured for mounting to the truss and for being movable along a length of the truss.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Application Ser. No. 60/922,056, filed on Apr. 5, 2007, entitled Floor Grinding Machine; the prior application is herewith incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
       [0002]    The invention relates to a machine for grinding concrete floors that need to be flat, more specifically, to a grinding machine that can be installed to grind a floor, thereby making the floor planar. 
         [0003]    Existing floor grinders are not able to produce a flat floor or a level floor that is flat over its entire surface area. For many years floor-covering professionals have gone to great lengths to remove high and low spots commonly found on concrete floors. While most floor grinders have reduced the time necessary to prepare a floor, by quickly removing adhesives and excess cement, they still have not been able to produce a flat surface to work on. Conventional floor grinders have rotating discs that make the floor flat within an area limited to the surface area of the discs but not relative to the rest of the area of the floor. Furthermore, these grinders are moved around the floor by way of wheels which simply roll over the high and low spots and therefore, they do not compensate for the varying elevations of the floor. The operator of the grinder, while working on area of the floor, has no idea how it correlates to the other areas of the floor. In order to see these high and low spots one must put a straight edged tool on the floor in both an “x” and “y” direction. Therefore, use of such conventional grinders relies greatly on skill and the time spent devoted to leveling the floor. 
         [0004]    The popularity of larger ceramic and marble tiles and smaller grout joints has made it even more difficult for installers to produce a flat finished product. Many installers will attempt to make a floor flat by “floating” it. This is a costly and time consuming process in which the low spots are filled in with cement to make them even with the high spots. Once again, this is only possible by using a straight edge. Marble or stone applications require that the installer must raise the entire floor up on a bed of cement in order to accommodate the unevenness of the floor. This installation process requires an enormous amount of cement and is extremely time consuming. The ability level the floor before putting down the tiles would greatly cut installation costs. 
       BRIEF SUMMARY OF THE INVENTION 
       [0005]    It is accordingly an object of the invention to provide a floor grinding machine which overcomes the above-mentioned disadvantages of the heretofore-known devices of this general type and which provides a floor grinding machine that is accurate, easily manufactured, easy to maintain, quick and simple to use, has a great deal of versatility, and is reliable. 
         [0006]    The present invention has the advantages that it can be set up on any floor surface and level a floor that is highly uneven. 
         [0007]    The simplicity of the present invention allows anyone with various skill levels to successfully the use the floor grinding machine. It is very lightweight and extremely portable and can be set up to cover surface areas of varying shapes and sizes. 
         [0008]    The present invention pertains to a floor grinding machine used to remove irregularities in the surface of concrete floors so that they may be covered easily and maintain a flat or level appearance. The present invention uses straight, level beams as guides to grind away the elevation variations commonly found in the surface of concrete floors. The floor grinding machine not only removes excess matter left behind by previous floor coverings but also produces an ideal surface to be covered with new flooring. The floor grinding machine has the advantage of a rate of production associated with the popular multidisc grinders while surpassing the shortcomings thereof by eliminating uneven areas in the floor. The present invention does not roll across the floor on wheels leaving uneven areas unaddressed. To the contrary, the floor grinding machine is suspended above the floor by a level framework of beams that act as a guide for removal of the uneven areas. 
         [0009]    With the foregoing and other objects in view there is provided, in accordance with the invention a floor grinder assembly for grinding a floor. The assembly includes first and second rails configured for being mounted spaced apart from and parallel to one another. A plurality of stands is configured for mounting the first and second rails above the floor. The stands have an adjustable length for adjusting a height position of the first and second rails such that the rails define a plane above the floor. A truss is configured to mount between the rails and to be movable along a length of the rails. A grinding assembly includes a grinding wheel and a motor driving the grinding wheel. The grinding assembly is configured for mounting to the truss and for being movable along a length of the truss. 
         [0010]    With the rails in a north-south direction and the truss in an east-west direction, together they form a plane above the floor. This plane can be manipulated very precisely to be level or pitched. The manipulation and height of the plane comes by way of adjustable stands located on both ends of each rail. The concept of the level plane is actually the basis of the invention. Once the level plane has been established, and the machine has passed over the entire floor, the floor itself will be a level plane. The mounting of the truss establishes a plane above the floor, which can be manipulated to be level, pitched or flat and acts as a guide by which the floor will be planed. The advantage of such a machine is that it produces the most ideal surface of a concrete floor to be covered. 
         [0011]    In accordance with another feature of the invention, the assembly includes a carriage, said carriage has a housing configured for selectively mounting said grinding assembly to said truss. 
         [0012]    In accordance with an additional feature of the invention the housing has rollers configured to roll on said truss and a hinged wall for releasably attaching said housing to said truss. 
         [0013]    In accordance with yet another feature of the invention, the rails and said truss are formed of rail segments. The segments have locating pins and corresponding holes configured for axially mounting said segments to one another. 
         [0014]    In accordance with yet a further feature of the invention, said truss includes sliding sleeves configured for being selectively affixed to opposite ends of said truss, the sleeves are configured for movably mounting said truss to said rails. 
         [0015]    In accordance with a further feature of the invention, the stands each have: a harness configured for removeably mounting said stand to said rails, a base, a threaded piston projecting from said base and being attached to said harness, and a threaded coupling disposed on said base for adjusting position of said threaded piston and thus said harness. 
         [0016]    In accordance with an added feature of the invention, the carriage has a pair of spaced apart legs mounted on said housing. The said legs each have a respective sleeve mounted thereon opposite said housing. The grinding wheel is rotatably mounted between said sleeves. 
         [0017]    In accordance with yet an added feature of the invention, the legs each have a respective array of holes and said sleeves each have a respective array of holes. Pins are configured to be inserted into corresponding holes thereby locking said sleeves with respect to said legs and establishing a height of said grinding wheel with respect to the truss and the floor. 
         [0018]    In accordance with yet an additional feature of the invention, one of said legs has a step for offsetting a bottom portion of said leg thereby allowing said grinding wheel to travel beyond said rail facing said leg with said step. 
         [0019]    In accordance with still another feature of the invention, the housing has a locking device configured for locking the carriage at a fixed position on said truss. 
         [0020]    In accordance with still yet another feature of the invention, the grinding wheel has a protective shroud. 
         [0021]    Other features which are considered as characteristic for the invention are set forth in the appended claims. 
         [0022]    Although the invention is illustrated and described herein as embodied as a floor grinding machine, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 
         [0023]    The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0024]      FIG. 1  is a diagrammatic perspective view of the floor grinding machine according to the invention; 
           [0025]      FIG. 2  is an enlarged perspective view of a rail segment according to the invention; 
           [0026]      FIG. 3  is an enlarged perspective view of a stand according to the invention; 
           [0027]      FIG. 4  is an enlarged perspective view of a truss and grinding carriage assembly according to the invention; 
           [0028]      FIG. 5  is an enlarged perspective view of a grinding wheel according to the invention; 
           [0029]      FIG. 6  is an enlarged perspective view of the grinding carriage assembly according to the invention; and 
           [0030]      FIG. 7  is an enlarged perspective view of the grinding carriage assembly housing according to the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0031]    Referring now to the figures of the drawing in detail and first, particularly, to  FIG. 1  thereof, there is seen a floor grinding machine or floor planer  100  according to the invention. The grinding machine  100  makes it possible to grind a floor in a plane that is level or that is sloped in a specific direction. 
         [0032]      FIG. 1  shows the concrete floor planer  100  assembled according to the invention. The floor planer  100  includes two horizontally rails  1  that are spaced apart from one another and which are parallel to one another. The rails  1  are supported and suspended by four adjustable stands  2 . One stand  2  is mounted at each of the opposing ends of both of the rails  1 . The floor planer  100  also includes a horizontal truss  3  that is perpendicular to and mounted to each rail  1  at opposite ends of the truss  3 . The truss  3  is movably mounted to the rail  1  by two sliding sleeves  4  removeably mounted on the opposite ends of the truss  3 . The sleeves  4  allow the truss  3  to move along the length of the rails  1  between the stands  2 . The floor planer  100  includes a grinding carriage  5  movably mounted on the to the truss  3 . The carriage assembly  5  is movable along the length of the truss  3  between the two rails  1 .  FIG. 1  also shows that the grinding carriage  5  includes a motor  6  for driving a grinding wheel  26  and a protective shroud  7  adjacent the grinding wheel  26 . The motor is approximately two H.P., 15 amps and has a speed of 12,000 R.P.M., which is consistent with most concrete grinding. The mounting of the truss  3  establishes a plane above the floor, which can be manipulated to be level, pitched or sloped and acts as the guide with which the floor may be planed. 
         [0033]      FIG. 2  shows a rail segment  8 , which is one of the rail segments  8  that makes up the rails  1 . Each rail segment  8  is approximately six feet in length and includes two parallel spaced beams  9  connected by a series of support studs  10 . The rail segment  8  is capped on each opposing end by a connecting plate  11 . Both support studs  10  and connecting plates  11  are affixed perpendicularly to the parallel beams  9 . In order to join multiple rail segments  8  to one another, one connecting plate  11  has two threaded pins  12  the connecting plate  11  at the opposite end has holes  13  formed therein corresponding to the spacing of threaded pins  12  of the adjacent rail segment  8 . The pins  12  of one segment  8  are inserted into the holes  13  in an adjacent rail segment  8 . The pins  12  are secured in the holes  13  with a threaded nut. The holes  13  and the pins  12  are constructed so that the rail segments  8  can be connected into a smooth continuous rail  1 . The above-noted connection is only an example of how the rail segments  8  may be connected, however there are many different way to achieve the same continuous rail  1  that are within the scope of the present invention. The truss  3  can also be constructed of segments in a similar manner. This type of system allows the floor planer to be applied to different shapes of areas and also allows for easy assembly and transport. 
         [0034]      FIG. 3  shows the adjustable stand  2 , which sits upright on the floor and has a base  14  at the bottom thereof. Extending outwards from the base  14  are legs  15  for stability. A threaded piston  16  projects from the base  14 . The piston  16  is raised or lowered by turning a threaded coupling  17  mounted on the threaded piston  16  at the top of the base  14 . An open-ended harness  18  is affixed to the top of the piston  16 . The harness  18  slides onto the rail  1  and securely affixes to the rail  1 . Although not shown in  FIG. 3 , it is possible for the base  14  to have holes formed therein so that the base may be fastened to the floor. 
         [0035]      FIG. 4  is an enlarged view of the grinding carriage  5  movably mounted on the truss  3 . The hollow, boxlike, upper area of the carriage  5  is known as the upper housing  19 . The housing  19  is affixed to the truss  3  and allows the grinding carriage  5  to move along the truss  3 . Extending from the upper housing  19  are two spaced apart vertical legs  20 . The vertical legs  20  are connected and supported by a cross member  21 . One leg has a step  2 , which offsets a bottom portion of the leg  20  with respect to a top  20  portion of the leg. The step  22  is approximately four inches, which allows the machine to pass under the corresponding rail  1  closely to a wall. The bottom portion of the carriage  5  is the grinding assembly  101 . The grinding assembly  101  of includes two vertical sleeves  23  which each mate with respective ones of the legs  20  for adjustably attaching the grinding assembly  101  to the carriage  5 . The grinding assembly  101  includes the grinding wheel  26  shroud  7 , the motor  6 , a torque limiter  33  ( FIG. 6 ), and a water attachment port  27  for attaching a water supply line (not shown). 
         [0036]      FIG. 5  is an enlarged view of the grinding wheel  26 . The grinding wheel  26  may be approximately 8-10 inches long. The grinding wheel includes an axle  28 , a drum  29 , and diamond segments  30 . The drum  29  is tubular in shape and approximately three inches in diameter. The axle  28  runs through the middle of the drum  29  and sticks out both ends. Located around the entire circumference of the drum  29  are a series of diamond segments  30  protruding outwards from the surface of the drum  29  and spaced approximately ⅛ inch apart. Each segment  30  spans the length of the drum  29 , has a width of approximately Y2 inch and a height of 10 MM. The segment  30  is a blend of metals and synthetic diamonds designed for optimum grinding. The axle  28 , drum  29  and segments  30  are of uniform construction and rotate on a horizontal axis as a solid unit. 
         [0037]      FIG. 6  shows an enlarged view of the grinding assembly  101 . A section of the shroud  7  is cut away to show the water duct  31  and the grinding wheel  26 . The water duct  37  is fluidically connected to the water attachment port  27  and has holes formed along its length for fluid flow. The grinding assembly  101  can be raised or lowered by way of the height adjustment holes  32  formed at the top of each sleeve  23  and at the bottom of the legs  20  and removable pins  36  that are inserted into the proper holes  32 . By manually lifting the assembly  101  as a whole, the sleeves  23  slide up the legs  20  until the holes  32  at the top of the sleeve  23  line up with the desired holes  32  in the legs  20 . Then the pins  36  are inserted into the proper holes  32 , this secures the assembly at that position. The height adjustment of the assembly enables the machine to run without the grinding wheel  26  engaging the floor. Moreover, the height adjustment of the assembly also gives the operator control of the depth of the cut of the wheel. For example, if one particular area of the floor needs to be reduced more than ½ inch, the height adjustment of the assembly allows the machine to make a series of ¼ inch deep passes without readjusting the height of the stands. The grinding wheel  26  is powered by the motor  6  which is protected by the torque limiter  33  should the wheel  26  bind to the concrete. 
         [0038]      FIG. 7  shows an enlarged view of the housing  19 . The grinding carriage  5  attaches to the truss  3  by way of the hollow housing  19 . The housing  19  has rollers  119  inside that allow the carriage  5  to move back and forth along the truss  3 . The housing  19  has a locking device  319  for locking the housing at a fixed position on the truss  3 . One side of the housing  19  opens with a hinge  219 , thereby allowing for easy mounting and reversing of the carriage  5 . The reversing if of the carriage  5  allows the step  22  to be reversed to face the opposite rail  1  thereby allowing the grinding wheel  26  to cut close to the wall along the opposite rail  1 . 
         [0039]    It is possible for the sleeves  4  to be constructed in a similar manner to the housing  19 . Although not shown in the drawings, it is possible for the carriage  5  to have drive for advancing the carriage  5  along the truss  3 . Furthermore, it is possible for the truss  3  to include a drive for advancing the truss  3  along the rails  1 . It follows that the sensors and a control unit can be included to control the drives for the advancement of the carriage  5  and the truss  3  based on appropriate cutting feed rates and to control the motor  6  for setting appropriate cutting speed rates. It within the scope of the invention to employ laser-leveling devices for leveling and adjusting the rails  1  with respect to one another.