Abstract:
A base beam for formation of a horizontal and vertical, rod-like framework for use in clamping workpieces to be measured, includes a main body defined by a substantially square cross section and having drawn-in flanks formed centrally with a rib, and a carriage detachably securable on the main body for displacement longitudinally in direction of the main body, with the carriage having at least one side formed with one or more precision bores.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application claims the priority of German Patent Application Serial No. 198 10 771.4-15, filed Mar. 6, 1998, the subject matter of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     The present invention relates, in general to frameworks, and more particularly to a base beam for use in realization of a horizontal and vertical, rod-like framework for clamped attachment of workpieces to be measured. 
     Conventional clamping systems for attachment of workpieces in the measuring technique typically utilize in addition to base plates primarily precision-bored beams which are used for realizing a basic vertical and horizontal framework and oftentimes are of great length. These precision-bored beams are formed with a continuous raster of bores. These bores as well as the spacing between the bores are manufactured at high precision so that the overall costs of such precision-bored beams are substantial. 
     The provision for such expensive precision-bored beams with the plurality of precision bores, however, is frequently not required, in particular in situations where a user has a need for precision bores only at the ends or in the center of the precision-bored beams. In these situations, the provision of the other precision bores is redundant. 
     SUMMARY OF THE INVENTION 
     It is thus an object of the present invention to provide an improved framework, obviating the afore-stated drawbacks. 
     In particular, it is an object of the present invention to provide an improved framework of horizontal and vertical structure which can be suited to a customer&#39;s needs and is more flexible with respect to the clamping task and thus more cost-efficient, without adversely affecting a required precision. 
     These objects, and others which will become apparent hereinafter, are attained in accordance with the present invention by providing a base beam having a main body which is defined by a substantially square cross section and has drawn-in flanks formed centrally with a rib, whereby the base beam is complemented by a first carriage which is detachably securable on the main body for displacement longitudinally in direction of the main body, with the carriage having at least one side formed with one or more precision bores. 
     Suitably, a second carriage is so associated to the first carriage as to be movable transversely to the base beam, with the second carriage also having at least one side formed with one or more precision bores. 
     According to another feature of the present invention, a connector kit is provided which is attachable to at least one end face of the main body for coupling the base beam to a conventional precision-bored beam. 
     According to still another feature of the present invention, each of the first and second carriages has a bottom side of half-dovetailed configuration, with a clamping mechanism disposed in the bottom and including a swingable clamping member for cooperation with one or more screw fasteners. 
     Through the provision of a base beam according to the present invention, a framework can be established which can be suited to the customer&#39;s needs in a highly cost-efficient manner, e.g. for purposes of precise clamping and subsequently measuring of workpieces. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The above and other objects, features and advantages of the present invention will now be described in more detail with reference to the accompanying drawing, in which: 
     FIG. 1 is a front view of a base beam according to the present invention; 
     FIG. 1 a  is a partially sectional, side view of the base beam of FIG. 1; 
     FIG. 2 is a front view of the base beam of FIG. 1 in conjunction with an attached carriage; 
     FIG. 2 a  is a partially sectional, side view of the assembly of base beam and carriage of FIG. 2; 
     FIG. 2 b  is a partially sectional, top view of the assembly of base beam and carriage; 
     FIG. 3 is a front view of the base beam of FIG. 1 in conjunction with two attached carriages; 
     FIG. 3 a  is a partially sectional, side view of the assembly of base beam and two carriages of FIG. 3; 
     FIG. 3 b  is a partially sectional, top view of the assembly of base beam and two carriages; 
     FIG. 4 is a front view of the carriage of FIG. 2; 
     FIG. 4 a  is a side view of the carriage of FIG. 4; 
     FIG. 4 b  is a top view of the carriage of FIG. 4; 
     FIG. 5 is a schematic illustration of a clamping member for securement of a carriage; 
     FIG. 5 a  is a schematic side view of the clamping member of FIG. 5; and 
     FIG. 6 is a top and side perspective view of a fragmentary framework comprised of a base beam according to the present invention and other conventional elongated, rod-like beams. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Throughout all the Figures, same or corresponding elements are generally indicated by same reference numerals. 
     Turning now to the drawing, and in particular to FIGS. 1 and 1 a , there are shown a frontal view and a side view of a base beam, generally designated by reference character B and including an elongated hollow main body  1  which is of substantially square cross section and formed with a central hole  17 . The main body  1  is formed on each side thereof with inwardly directed converging flanks  2  which terminate in a central rib  3  extending longitudinally along the main body  1 . The main body  1  has opposite end faces  8  which have formed therein bores  15  and  15 ′ of different sizes, and threaded bores  16  in the area of the ribs  3 , to allow attachment of the base beam B to other beams, such as precision-bored beams formed with a raster of precisely formed and spaced-apart bores  6 , through use of a suitable connection kit  9 , as shown, for example, in FIG.  6 . Suitably, the main body  1  is made through extrusion. 
     Unlike conventional precision-bored beams, shown in FIG. 6 by way of example and labeled by reference numeral  10 , the base beam B does not have any precision bores  6  for attachment of a workpiece. However, in order to permit precise attachment of a workpiece to the base beam B of the present invention as well, a carriage  4  is provided which can be detachably mounted at any suitable location onto the main body  1 , as shown in FIGS. 2,  2   a  and  2   b . The carriage  4  is of generally U-shaped configuration (cf. FIG. 4) so as to be placeable over one flank  2  of the main body  1 . On its main body distal side  5 , the carriage  4  is formed with one or more precisely shaped and spaced-apart bores  6  for attachment of a workpiece. As best seen in FIG. 2, the carriage  4  is secured to the main body  1  by a clamping member  13  (cf. also FIGS. 5 and 5 a ) which is pivotally mounted at the underside  11  of the carriage  4  for rotation inwardly toward the main body  1  in direction of arrow  18  (FIG.  4 ). The inward rotation of the clamping member  13  is realized by one or more screw fasteners  14  which are received in respective throughbores  19  that are accessible from outside to allow engagement of an appropriate tool (not shown). By screwing the screw fastener or screw fasteners  14  inwardly, the clamping member  14  is urged against the confronting flank  2  of the main body  1  to secure the carriage  4 . 
     The carriage  4  can be displaced longitudinally along the main body  1  and is so dimensioned as to permit a second carriage  7  which is also formed with precision bores  6  to be placed over the main body distal side of the carriage  4 . This configuration is shown in particular in FIGS. 3,  3   a  and  3   b , and allows certain mounting tasks that require a displacement in a transverse direction and thus vertical with respect to the base beam B. The securement of the carriage  7  to the carriage  4  is realized in a same manner as the securement of the carriage  4  to the main body  1  of the base beam B, and thus includes a clamping  13  which is urged by one or more screw fasteners  14  against a confronting wall of the carriage  4 . 
     The carriages  4  and  7  are of identical design and are shown in FIGS. 4,  4   a  and  4   b , without illustration of the base beam B. The clamping member  13  is disposed in the recess at the underside  11  which is of half-dovetail configuration, whereby the other half of the dovetail is formed by the clamping member  13 , when the carriage  4 ;  7  is placed accordingly, and the clamping member  13  is rotated inwardly by the screw fastener  14 . 
     Turning now to FIG. 6, there is shown a top and side perspective view of a fragmentary framework comprised of a base beam B according to the present invention and other conventional elongate precision-bored beams  10  to illustrate a situation in which precision bores  6  are needed only at certain locations. The base beam B is shown without carriages  4 ,  7  and thus does not exhibit any precision bores  6 . Each axial end face  8  of the base beam B is linked by a connection kit  9  to a confronting end face of a precision-bored beam  10  which is formed with precision bores  6 . The framework of FIG. 6 is shown by way of example only. Certainly, the configuration may differ to suit other clamping tasks. For example, the base beam B may require the use of one or more of the detachably secured carriages  4 ,  7  to permit attachment of respective workpieces. 
     While the invention has been illustrated and described as embodied in a base beam for use in frameworks for mounting workpieces to be measured, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.