Patent Publication Number: US-2010122510-A1

Title: Cage spacer with roller wheel

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Benefit of U.S. Provisional Application for Patent Ser. No. 61/193,328, filed on Nov. 18, 2008, is hereby claimed. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a spacer, and is more particularly concerned with a cage spacer for spacing a reinforcement structure apart from a forming surface of a forming structure during formation of a cementitious structure in the forming structure. 
     BACKGROUND OF THE INVENTION 
     Cage spacers for cement forming structures, for example a mould, for forming cementitious structures are well known in the art. Such spacers typically have a bracket having an inner face attached to and abutting against a reinforcement structure, for example a cage, with a cylindrical roller wheel, freely and rotatably mounted in the bracket with a portion of the circumference thereof extending beyond an outer side, disposed opposite the inner face of the bracket. Thus, one or more spacers may be attached to the reinforcement structure, preferably spaced apart around a perimeter thereof, with the outer facing away therefrom. The reinforcement structure may then be easily placed in a mould, or other forming structure, by rolling the reinforcement structure into the forming structure on the roller wheels. At the same time, each roller wheel is mounted on the bracket and is sized and shaped such that that the distance between the forming surface of the forming structure, against which the roller wheel abuts and rolls, and the cage, against which the inner face abuts, is equal to the desired spacing. Thus, use of the spacer also ensures that the desired spacing between the forming surface and the reinforcement structure are maintained. 
     Unfortunately, such conventional spacers often have metal or glass components, which may be expensive and damaged by cementitious materials such concrete or cement. Further, the roller wheels for conventional roller spacers are typically not removable or replaceable. Thus, the distance of the spacing provided by such spacers is not adjustable. Further, should the roller wheel be defective, then the entire spacer must be discarded and replaced. 
     Accordingly, there is a need for an improved spacer for spacing a reinforcement structure apart from a forming surface of a forming structure during formation of a cementitious structure in the forming structure. 
     SUMMARY OF THE INVENTION 
     It is therefore a general object of the present invention to provide an improved cage spacer for spacing a reinforcement structure, such as a cage, apart from a forming surface of a forming structure during formation of a cementitious structure in the forming structure. 
     An advantage of the present invention is that the spacer can provide an adjustable spacing at an adjustable distance for the reinforcement structure relative the forming surface. 
     Another advantage of the present invention is that the spacer is resistant to damage and impediment by the cementitious material of which the cementitious structure is formed. 
     In one aspect, the invention provides a cage spacer for spacing a reinforcement structure apart at a predefined distance from a forming surface of a forming structure for a cementitious structure during formation of the cementitious structure therein, the cage spacer comprising:
         a bracket having an attachment face and a generally opposed roller face, the bracket being connectable to the reinforcement structure with the attachment face abutting thereagainst; and   a cylindrically shaped roller wheel rotatably mounted in the bracket with an outer circumferential surface thereof extending from within the bracket partially beyond the roller face, the roller wheel being sized and positioned relative the attachment face for abutting and rolling of the outer circumferential surface against the forming surface at the predefined distance from the reinforcement structure, thereby spacing the reinforcement structure apart from the forming surface at the predefined distance and enabling rolling of the reinforcement structure into the forming structure at the predefined distance from the forming surface, the bracket and the roller wheel being constructed of a plastic material.       

     Other objects and advantages of the present invention will become apparent from a careful reading of the detailed description provided herein, with appropriate reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further aspects and advantages of the present invention will become better understood with reference to the description in association with the following Figures, in which similar references used in different Figures denote similar components, wherein: 
         FIG. 1  is a top perspective view of an embodiment of a cage spacer in accordance with an embodiment of the present invention; 
         FIG. 2  is an exploded view of the spacer shown in  FIG. 1 ; 
         FIG. 3  is a top plan view showing the spacer of  FIG. 1  in use in a mould for a cementitious structure; 
         FIG. 4  is a sectional view, taken along line  4 - 4  of  FIG. 3 , showing the spacer of  FIG. 1  in use in a mould for a cementitious structure; and 
         FIG. 5  is a top perspective view showing the spacer of  FIG. 1  in use in a mould for a cementitious structure. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the annexed drawings the preferred embodiments of the present invention will be herein described for indicative purpose and by no means as of limitation. 
     Referring to  FIGS. 1 and 2 , there is shown an embodiment of a cage spacer, shown generally as  10 , in accordance with the present invention. The spacer  10  consists of a bracket, shown generally as  12 , having generally first and second opposed side frames, shown generally as  18 , preferably identical. The side frames  18  each have a, preferably straight, bottom side  24  and a generally opposed top side  26 , the sides  24 ,  26  of each side frame  18  being connected to one another at longitudinally opposed frame ends  20  by a vertically extending side connecting member  28 , as well as by a plurality of spaced apart side connecting members  28  extending therebetween and which connect the bottom and top sides  24 ,  26  of each side frame  18 . 
     The frames  18  are, in turn, connected to one an other by a plurality of spaced apart frame connecting members  22  extending between and connecting the top sides  26  and bottom sides  24 , with the exception of a central portion of the frames  18 , where a cylindrically shaped side socket  30  is formed in, preferably centrally situated, side mounting wall  50  of each side frame  18 . The bottom sides  24  and horizontal members  22  extending therebetween define a, preferably straight and planar, attachment side or face  16  for the bracket  12 , whereas the top sides  26  and horizontal members  22  extending therebetween form an outer roller side or face  14  for the bracket  12 , disposed generally opposite the attachment face  16 . 
     As shown in  FIGS. 1 and 2 , the first and second side sockets  30  are axially aligned with one another along axis X and house a cylindrically shaped roller wheel, shown generally as  32 , mounted therein. Specifically, the first and second side sockets  30  are disposed in the side wall  50  of each side frame  18 . The side mounting wall  50  extends from the top side  26  downwardly to the bottom of the side socket  30  and, preferably, therebeyond to the bottom side  24 . Preferably the top side  26  slopes upwardly, again preferably in a central portion of the bracket  12 , towards the side mounting wall  50 , such that each side mounting wall  50  is elevated relative the longitudinal ends  20 . Thus, the top side  26  is relatively further spaced apart from the bottom side  24  at the side mounting wall  50  compared to the frame ends  20 . 
     The frame and side connecting members  22 ,  28  advantageously reinforce the bracket  12  and help to prevent compression or deformation thereof during use of the spacer  10 . 
     Referring now to  FIGS. 1 through 4 , the roller wheel  32  consists of centrally situated inner cylinder  34  and an outer cylinder  36  connected to the inner cylinder  34  by radial support members or arms  38  extending therebetween. The inner cylinder  34  extends axially along axis X through outer cylinder  36  and slightly beyond the radial support arms  38  and the outer cylinder  36  on both wheel sides, shown generally as  44 , of the roller wheel  32 , Thus, the inner cylinder extends slightly beyond the outer cylinder ends  40  of the outer cylinder  36  and the arm end  42  of the radial support arms  38 , which together form the wheel sides  44 , and into the side sockets  30 . 
     The inner cylinder  34  extends into the side sockets  30  when the roller wheel  32  is mounted in the bracket  12  and provides the rotatable mounting of the wheel  32 . The inner cylinder  34  is of slightly lesser circumference than the side sockets  30 , and is thus sized and shaped to be freely rotatable in the side sockets  30  while loosely abutting an inner socket surface of each side socket  30 . Advantageously, this loose abutment of the side socket  30  against inner socket surface allows free rotation of the roller wheel  12  in the side sockets  30  while promoting stability of the roller wheel  32  by reducing wobbling of the roller wheel  32  in the side sockets  30 . At the same time, the radial support arms  38  provide reinforcement of the wheel  32  when the spacer  10  is placed with in the forming structure  54 , shown as mould  54  in  FIGS. 3 and 4 , with the reinforcement structure  56 , shown as cage  56 , and helps ensure that the wheel  32  is not squashed or compressed during use, which could compromise the spacing between the reinforcement structure  56  and the forming structure  54 . 
     The respective thickness T 1  of the radial support arms  38  and the outer cylinder  36  between the wheel sides  44  is less than the distance D 1  between the respective interior sides  46  of the support frames  18 . Thus, the side frames  18  are spaced slightly further apart between respective interior sides  46  than a thickness of the radial support arms  38  and the outer cylinder  36 . Accordingly, the roller wheel  32  is sized and shaped such that when it is housed in the side sockets  30 , it may rotate freely without being obstructed by the side frames  18 . Similarly, the radius R 1  of the roller wheel  32  is less than the vertical distance D 2  between the centre of the side socket  30  and the frame connecting members  22  extending between the bottom sides  24  of the side frames  18 . Accordingly, the wheel  32  is also sized and shaped such that when it is mounted in the side socket  30  it may freely rotate without obstruction by the frame connecting members  22  extending between the bottom sides  24  of the side frames  18 . The distance between the side mounting walls  50  at the interior sides  46  is, preferably slightly, less than the thickness of the inner cylinder  34  extending between inner cylinder ends  52  thereof. Thus, the inner cylinder  34  is retained in the sockets  30  to prevent unwanted dislodging of the inner cylinder  34  from side sockets  30 . 
     Referring still to  FIGS. 1 through 4 , the roller wheel  32  is further sized and shaped, with regard to the radius R 1  thereof, such that an outer circumferential portion of the outer circumferential surface  64  of the wheel  32 , notably of the outer cylinder  36 , extends beyond the top side  26  when the wheel  32  is mounted in side sockets  30  of the bracket  12 . Thus, the outer circumferential surface  64  extends from within the bracket  12  beyond the roller face  14 . 
     When the spacer  10  is connected to the reinforcement structure  56 , typically with the frame connecting members  22  of the attachment face  16  abutting against the reinforcement structure  56 , the reinforcement structure  56  can be inserted into the forming structure  54  with the roller wheel  32 , specifically the outermost point of the circumferential surface  64  against the forming surface  58  of the forming structure  54 . As the roller wheel  32  is freely rotatable in the side sockets  30 , the reinforcement structure  56  can be rolled on the wheel  12  into the forming structure  54 . At the same time, the spacer  12  maintains the reinforcement structure  56 , or the portion thereof supported thereby, spaced apart from the forming surface  58  at a distance D 3  equal to the distance between the attachment face  16  and the point of contact, situated on the outer circumferential surface  64 , of the wheel  32  and the forming surface  58 . Thus, by providing a rolling wheel  32  of appropriate radius, which determines the circumference thereof, and a bracket  12  having the sockets at a desired distance from the attachment face  16 , a spacing of the cage  56  at a desired predetermined distance from the forming surface  58  can be provided. 
     The bracket  12 , and in particular the side mounting walls  50 , are constructed of a sturdy, but slightly resilient plastic, such that the frames  18 , and in particular the side mounting walls  50  are slightly outwardly and resiliently movable to provide removable insertion of said roller wheel into said side sockets between the side mounting walls  50 . To further facilitate mounting or seating of the roller wheel  32  in the side sockets  30 , the bracket  12  has, preferably centrally situated, guide indentations  48  extending into the side mounting wall  50  in each side frame  18 , from the top side  26  down to the side socket  30 . The guide indentation  48  is of similar, but slightly greater, width than the outer circumference of the inner cylinder  34 . Further, the guide indentations  48  are recessed into the interior of the side mounting wall  50  such that the inner cylinder  34  may be slid or pushed into the indentations  48  with the inner cylinder ends  52  disposed proximal and possibly abutting the interior of the side mounting wall  50  in the indentations  48 . Thus, roller wheel  32  may be mounted in the side sockets  30  by positioning the roller wheel  32  with the inner cylinder ends  52  aligned with guide indentations  48  and then forcing or wedging the roller wheel  32  towards side sockets  30  with the inner cylinder ends  52  engaged in the indentations  32 . As the inner cylinder  34  is inserted in the indentations  48  towards the side socket  30 , the side mounting walls  50  are biased or forced slightly away from one another, until the inner cylinder  34 , and notably the ends  52  thereof, are housed, i.e. snap into, the side sockets  30 . At this point, the walls  50  bias back towards one another due to the rigid nature of the plastic. To remove the roller wheel  30 , the side walls  50  need only be slightly pulled apart from one another and the inner cylinder  34  moved away from the side sockets  30  through the guide indentations  48  until the wheel  32  is removed. 
     As one skilled in the art will appreciate, the ability to easily insert and remove the roller wheel  32  presents a number of advantages over the prior art. For example, one may easily replace defective roller wheels  32 . Additionally, one may choose and install roller wheels  32  of differing radii, and therefore differing circumferences, to adjust the amount of spacing provided to a desired predefined distance for the reinforcement structure  56  from the forming surface  58 , while still using a common bracket  12 . Additionally, all components of the spacer  10  are made of a solid plastic material, resistant to erosion or damage by cementitious materials such as concrete and cement which form the cementitious structure in the forming structure  54 . 
     Reference is now made to  FIGS. 1  though  5 . In use, after determining the predefined distance for the desired spacing of the reinforcement structure  56  from the forming surface  58 , a roller wheel  32  of appropriate circumference and bracket  12  of appropriate size are selected and the roller wheel  32  is mounted in the side sockets  30  through the guide indentations  48 . The bracket  12 , preferably the frame connecting members  22  of the attachment face  16 , is attached to the cage  56 , as shown in  FIGS. 3 ,  4 , and  5 , preferably with the attachment face  16  extending along and preferably abutting the reinforcement structure  56 . For example, the bracket  12  may be tied to the reinforcement structure  56  with wires  60 , the wires  60  being tied around one or more of the frame connecting members  22  of the attachment face  16  and the reinforcement structure  56 . Preferably, and as shown in  FIGS. 3 and 5 , a plurality of spacers  10  are so attached, spaced apart from one another around the perimeter of the reinforcement structure  56 , which is preferably of similar shape to the forming surface  58 . For example, and as shown, for a cylindrical reinforcement structure  56 , i.e. cage  56 , and forming structure  54 , i.e. mould  54 , spacers  10  are attached spaced apart from one another at various positions on the circumference of the cage  56 . However, it should be noted that the spacer  10  may be used with any shape of reinforcement structure  56  and forming structure  54 , provided that the spacing/distribution of the spacers  10  is such that the desired predefined distance of spacing for the reinforcement structure  56  relative the forming surface  58  of the forming structure  54  is maintained and that the reinforcement structure  56  can be rolled into the forming structure  54  on the spacers  10 . 
     Once the spacers  10  have been attached, the reinforcement structure  56  is rolled thereupon into the forming structure  54 . The cementitious material is then poured into the reinforcement structure  56  to form the cementitious structure. It should be further noted that spacers  10  could also be attached with the outer face  14  facing inwardly from the reinforcement structure  56  towards an outer forming surface of inner forming structure, not shown, positioned inside the reinforcement structure  56  for spacing the reinforcement structure  56  at a desired distance from the inner forming structure. The cementitious material may be any material commonly used for forming cementitious structures, including cement, concrete, asphalt, or the like. 
     Although the present invention has been described with a certain degree of particularity, it is to be understood that the disclosure has been made by way of example only and that the present invention is not limited to the features of the embodiments described and illustrated herein, but includes all variations and modifications within the scope and spirit of the invention as hereinafter claimed.