Abstract:
A section element for constructing frames, supporting structures and the like made up of a section body ( 10 ) having one or more flat surfaces ( 11 ) and one or more rounded sectors ( 12 ) as parts of a circumference with a preset diameter. In correspondence with each flat surface ( 11 ) a longitudinal groove ( 13 ) is provided with parallel borders defining undercuts ( 15 ). The section body can be connected to other elements by means of clamps ( 16 ) each one delimiting at least one cylindrical in diameter housing matching that of the cylindrical surface defined by the rounded sectors of the section body and having at least one additional centering member designed to fit in the groove along at least one of the flat surfaces.

Description:
FIELD OF THE INVENTION 
     This invention concerns an innovative section element in the form of a bar usable in particular, but nor exclusively, in making frames, supports, supporting structures and the like. 
     STATE OF THE TECHNIQUE 
     In making frames, supports, supporting structures and the like, both on a plane and three dimensional, at present tubular elements or even round cross section or polygonal cross section bars, mostly square are provided and used, with relative advantages and disadvantages that technicians working in the field are well acquainted with. 
     Usually, the tubular elements, that is the tubes for this use, are extruded, and joined when used in modular structures by means of linear, parallel, at an angle, T or three way, cross-shaped, etc. couplings or clamps, depending on the configuration of the structure to be made. The round cross-sectioned tubes do not require either constraints or limitations as regards to being fitted at an angle in the clamps or of the latter being fitted around the tubes. With polygonal cross-sectioned tubes on the other hand, the clamps have set positions, associated with the faces of each tube. 
     However, specific clamps are required for round tubes and other types of clamps for four-sided or polygonal tubes, in that the clamps for round tubes cannot be used for polygonal tubes, and vice versa. At the most, clamps for tubes with one cross-section shape are used in connecting the tubes with another cross-section shape, but with the use of and interposition of adaptors. In addition, for a possible combination of round tubes with square tubes for the same structure, clamps are required which have both a round and a square cross-section housing corresponding to the different tubes that require connecting. 
     Therefore it is evident, in the same way as for the composition of frames, supports and supporting structures according to the known technique, besides tubular elements with round and square cross-sections, there must be available at least two distinct series of clamps with different configurations that, also taking into consideration the various dimensions that tube cross-sections may have, implies making and having available, a large number of components that have a negative influence on tooling, construction and storing costs. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     The main object of this invention is to create the conditions by which a single extruded section may be sufficient and be used indifferently both as a tube or bar having a circular cross-section and as a tube o bar having a square, that is polygonal, cross-section, along any part of its length. 
     Another object of the invention is to provide a section element of aluminium or similar for forming frames, supports, etc, in which the characteristics of the round tubes and the square or polygonal tubes or bars with respective advantages are combined together and integrated. 
     Still another object of the invention is to provide a multivalent section element suitable to be combined with and connected both to other similar sections and with round tubes by the same type of connecting clamps. 
     Another object of the invention is to provide a section element which can be combined also with traditional round and square tubes by means of the usual clamps available on the market having compatible sizes. 
     Yet another object of the invention is to propose linear, at an angle, three-way, cruciform, etc. clamps, suitable for coupling both with the round and square, that is polygonal, component of the section element without limitations as regards to angular position when associated with the round component and with preset orientation when associated with square or polygonal component. 
     These object and implicit advantages which follow are achieved, according to the invention, with a section element characterized by a body having peripherally one or more flat surfaces and for the rest one or more circular sectors as part of a circumference, and in line with each flat surface a longitudinal groove with parallel borders forming undercuts, and wherein connecting clamps are associable to said section element, each forming at least one cylindrical housing having a diameter corresponding to that of a cylindrical surface formed by the circular sectors of the section body and at least an additional means of centring designed to engage the groove along at least one of said flat surfaces. 
     The flat surfaces of the section element can be advantageously, but not exclusively, four in number; correspondingly there will be four circular sectors, alternating with the flat surface. Thus, said flat surfaces correspond to the same number of parts of the sides of a square prism for a use of the section element such as a tube or bar having a square cross-section, whereas the rounded sectors correspond to the same number of parts of a cylindrical surface for a use of the section element like a round bar or tube, the flat surfaces resulting inside the cylindrical surface formed by the rounded sectors. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will however be illustrated more in detail in the continuation of this description made with reference to the enclosed indicative and not limiting drawings, in which: 
         FIG. 1  shows a view of a bar section in perspective according to the invention; 
         FIG. 2  shows an end view thereof; 
         FIG. 3  shows an exploded view of a clamp for connecting a bar section to another one; 
         FIG. 4  shows two bar sections assembled with the clamp in  FIG. 3 ; 
         FIG. 5  shows a side view of the group in  FIG. 4 ; 
         FIG. 6  shows an exploded view of a pair of clamps for joining two octagonal bar sections; 
         FIGS. 7 and 8  show the pair of clamps in  FIG. 6  before and after connection of the two octagonal bar sections; 
         FIG. 9  shows a side view of the group in  FIG. 8 ; 
         FIG. 10  shows an exploded view of a pair of clamps for connecting two parallel bar sections; 
         FIGS. 11 and 12  show the pair of clamps in  FIG. 10  before and after connecting the two parallel bar sections; 
         FIG. 13  shows a side view of the group in  FIG. 12 ; 
         FIG. 14  shows a tie type clamp; and 
         FIG. 15  shows an example of a use of the clamp in  FIG. 14  for connecting the two elements. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown, the section element of the invention includes a section body  10  with a prevalent length dimension and having, peripherally, in cross sections, one or more flat surfaces  11 , the remainder of the surface sectors being round  12 . 
     The section body  10  can be made by extruding aluminium or its alloys of preference with four flat surfaces  11  that alternate with an equal number of rounded sectors  12 . In the section body seen as a whole, the flat surfaces  111  form parts of the sides of a square prism B, the rounded sectors  12  join the flat surfaces and correspond to parts of a cylindrical surface A with a preset diameter D, and the flat surfaces  11  are on the inner side of the circumference of said cylindrical surface— FIGS. 1 and 2 . 
     A groove  13  is cut along each flat surface  11  with an opening formed by two parallel borders  14  defining internally, from opposite sides of the groove, two corresponding undercuts  15  the surface of which can be longitudinally grooved. 
     The section element  10  shaped in this way can be connected to other similar elements in various ways and even to conventional round and square tubes, by means of usual clamps for round or square tubes. The rounded sectors  12  define round outer surface engagement means for engagement by a round engagement part (e.g., a usual clamp for round tubes). The flat surfaces  11  define polygon outer surface engagement means for engagement by a polygonal engagement part (e.g., a usual clamp for square tubes). 
     But advantageously, this invention proposes a clamp  16  which can have different configurations, linear, at an angle, T, etc. and which is set up to connect up both to flat surfaces and to the cylindrical sectors of the section body  10 . 
     The clamp  16  comprises a first block  17  and a second block  18  which overlap and lock together by means of a series of bolts  19  and nuts  20  engaging coincident bores  17 ′,  18 ′ machined respectively in the two blocks. 
     The first block  17  has a flat base  21  and forms a substantially semi-cylindrical notch  22  that extends in length between two opposite sides of the block itself and that is open towards the second block  18 . This second block delimits in its turn a substantially semi-cylindrical notch  23 , facing towards the notch  22  of the first block to form with it, when the clamp  16  is assembled, a cylindrical housing the diameter D of which is compatible with the cylindrical sectors  12  of the section body  10 . 
     At least in the first block  17 , on opposite sides of its semi-cylindrical notch  22 , two recesses  24  are provided and in correspondence with each recess there is a bore  25  perpendicular to the flat surface  21  of the block itself. The bores  25  in said recesses  24  are provided to host bolts  26  to fix the clamp directly to any flat surface  11  of the section body  10  with the help of threaded anchoring elements  27  placed in the groove  13  running along a surface and engaging with the undercuts on the walls of said groove  13 . The anchoring elements  27  can be the same shape as the so-called hammer nuts or plates with a threaded hole in which to thread the bolts  26 . 
     On the bottom of the semi-cylindrical notch  22  at least in the first block  17  of the clamp, a centring member  28  is located, which is overhanging and designed to engage the opening of any groove  13  with the function of preventing the clamp from turning on the body section it is associated with and acting as a guide for the linear movement and positioning of the clamp along the flat surfaces  11  of said section body. 
     The centring member  28  can, for example, be in the shape of a key as shown in the drawing, it is applied in the semi-cylindrical notch and it can be removed to be used only when required. In order to be removed when needed, the centring device  28  can be provided with pins  29  which fit unto corresponding holes  30  provided in the bottom of the respective semi-cylindrical notch  22 . 
     A similar centring member  31  can be associated in the same way and with the same functions to the semi-cylindrical notch  23  of the second block  18  of the clamp, said centring member  31  being provided with pins  32  designed to engage in holes  33  machined in the bottom of said notch  23 . 
     The clamp  16 , on its own or connected to others, enables the connection of the section body  10  with other similar sections, using each time their flat surfaces, that is the prismatic part, or their cylindrical section. 
     In fact, a clamp  16  can be fixed on any flat surface  11  of the section body  10  and used to block another section body  10  in the housing formed by the respective blocks  17 ,  18 . In this way, the first block  17  is fixed to a groove  13  of a flat surface  11  of the section  10  by inserting bolts  26  in the bores  25  in the bottom of recesses  24  in the walls of the semi-cylindrical recess  22  of said block and engaging with the anchoring elements  27  that are provided in said groove and which engage the undercuts  15  inside the latter— FIGS. 4 and 5 . Then, between the first block  17  and the second block  18  of the same clamp  16  there can be a second section body  10  placed and held in position. This other section body can be blocked by connecting the blocks of the clamp  17 ,  18  together, by using a set of nuts and bolts  20 ,  19  so as to tighten them around the cylindrical sector of the second section body without using the centring members  28 ,  31 . In this case, the section, before blocking it, can be turned at an angle as required on its longitudinal axis. 
     By applying the centring members  28 ,  31  on the bottom of the semi-cylindrical notches  22 ,  23  of the clam blocks  17 ,  18 , the section element may on the other hand be blocked in the clamp according to a set angle and corresponding to the flat surfaces  11 . Consequently, in fact, the centring members engage the section element in the respective grooves  13 , stopping it from turning. 
     It is also possible to pair the clamps  16  to join two sections  10  using a cross formation—FIGS.  6 - 9 —or parallel—FIGS.  10 - 13 —each held and blocked in the cylindrical housing by a respective clamp, with or without centring members  28 ,  31 . The clamps are paired by resting the base  21  of the first block  17  of one clamp to the base  17  of the first block  21  of the other clamp and fixing all the blocks of both clamps together using suitable length bolts  19 ′ to tighten the sections  10  together. 
     By using a C clamp that is a tie clamp  34  as shown in  FIG. 14  it will also be possible to block two elements  35 ,  36  independently, e.g. two tubes or sections together or a tube or section with a tool or another device as shown in the example in  FIG. 15 , with the possibility of turning or directing an element differently from the other. The example of  FIG. 15  uses an alternate clamp  16 ′. 
     For this purpose, the tie clamp has two protruding tabs  37  each having a pair of bores  38  coinciding with the ones in the other to receive crossways, two blocking screws  39 ,  40 , The internal face of each tab  37  has two planes  41 ,  42  inclined in opposite directions which converge in an apex, resulting between the pair of bores and acting as an intermediate fulcrum  43 . Externally each tab has a groove  44  which facilitate flexibility when the tabs are engaged crossways by screws  39 ,  40 . 
     Practically, the tie clamp  34  is connected by a first screw  39  to a first element  35  and by another screw  40  to another element  36  to be associated with the first. Thanks to the intermediate fulcrum  43 , by fully tightening the first screw  39  and not the other screw  40  the clamp can be firmly blocked to the first element  35 , leaving the second element  36  loose so that it can be turned and/or moved axially in the clamp. On the contrary, by fully tightening the second screw  40  and not the first one  39 , it is possible to firmly block the second element  36  in the clamp and move the latter with respect to the first element  35  to which it is connected by said first screw. By firmly tightening both screws  39 ,  40  it will be possible to rigidly block the first and second elements without the possibility of moving one with respect to the other.