Abstract:
A joining press for joining the ends particularly of a conveyor belt, comprising lower and upper heating plates which can be engaged by pusher pads in order to apply the necessary pressure, the plates being supported by reaction beams to contain a load applied by the pusher pads, the reaction beams having seats for detachably accommodating reinforcement elements.

Description:
BACKGROUND OF THE INVENTION 
     As is known, joining presses for joining the ends of conveyor belts and the like are already commercially available which generally speaking have a pair of heating plates functionally connected to two pneumatic pads, which provide the necessary pressure to the plates which are pressed onto the belt and are connected, together with the heating plates, to two structural beams which provide contrast to the load applied by the pads. 
     As is evident, flexing of the beam when loaded must be as limited as possible to avoid modifying the geometry of the system, and the beam must further have a limited height in order to be able to work with belts which have a limited extension. 
     Another problem relates to the weight of the beam in order to allow its easy maneuverability. 
     Another aspect further consists in that the presses are provided in different sizes as a function of the widths of the belts, and therefore with the solutions of the background art it is necessary to provide reaction beams which in each instance must be designed and manufactured as a function of the load to which they must be subjected. 
     Consequently, production is very expensive, because it is not possible to unify the production of the beam, regardless of the width of the belt to which it will be applied. 
     Another problem is also linked to the difficulties in manufacturing such beam and to the complexity encountered for correct mating of the heating plate. 
     SUMMARY OF THE INVENTION 
     The aim of the invention is to solve the problems described above by providing a joining press for joining the ends particularly of a conveyor belt and the like which allows to vary the rigidity of the beam as a function of the context of application, without therefore having to resort to a specific design as a function of its dimensions. 
     Within this aim, an object of the invention is to provide a beam with variable rigidity in which it is possible to contain the weight considerably, contributing to easy maneuverability of such beam. 
     Another object of the present invention is to provide a press in which it is possible to have rapid assembly of the heating plate without having to resort to the use of screws. 
     A further object of the present invention is to provide a joining press which, thanks to its particular constructive characteristics, is capable of giving the greatest assurances of reliability and safety in use. 
     Another object of the present invention is to provide a joining press which can be obtained easily starting from commonly commercially available elements and materials and is also competitive from a merely economical standpoint. 
     This aim and these and other objects, which will become better apparent hereinafter, are achieved by a joining press for joining the ends particularly of a conveyor belt and the like according to the invention, comprising lower and upper heating plates which can be engaged by pusher pads in order to apply the necessary pressure, said plates being supported by reaction beams to contain a load applied by said pusher pads, characterized in that said reaction beams have seats for detachably accommodating reinforcement elements. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further characteristics and advantages will become better apparent from the description of a preferred but not exclusive embodiment of a joining press for joining the ends particularly of a conveyor belt and the like, illustrated by way of non-limiting example in the accompanying drawings, wherein: 
         FIG. 1  is a schematic perspective view of the press in the closed position; 
         FIG. 2  is a transverse sectional view of the reaction beam and of the heating plate; 
         FIG. 3  is a sectional view of a constructive variation of the pusher pad; 
         FIGS. 4 ,  5 ,  6  and  7  are sectional views of different types of reinforcement of the reaction beam; 
         FIG. 8  is a perspective cutout view of the detail of the connection of the heating plate to the end of the reaction beam; 
         FIG. 9  is an enlarged-scale view of the fixing for connecting the heating plate to the reaction beam. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the figures, the joining press for joining the ends particularly of a conveyor belt and the like, generally designated by the reference numeral  1 , comprises lower and upper heating plates, which are both designated by the reference numeral  2  and can be engaged by a pusher pad  3  of the pneumatic type which acts between the plate  2 , as will become better apparent hereinafter, and the reaction beam, generally designated by the reference numeral  4 . 
     A peculiarity of the invention consists in that the reaction beam  4  is provided so as to have a constant cross-section with an extruded element, preferably made of aluminum, which defines in a downward region a lower plate  11  on which the pad  3  acts; such lower plate is flanked by engagement wings  12 , which allow coupling, as will become better apparent hereinafter, to the heating plate. 
     The extruded element which constitutes the reaction beam defines seats  15  which are arranged in mutually opposite pairs and are preset for the removable insertion and accommodation of reinforcement elements  16 , which are constituted by laminas which remain locked between mutually opposite seats  15 , so as to be able to vary the actual rigidity as a function of the size of the beam, without penalizing weight excessively. 
     As shown in the cross-sections, a central partition  17  is provided which protrudes from the lower plate  11  and blends, at the other end, with covering portions  18 , which provide an outer seat  20  arranged on mutually opposite sides for connecting the locking elements  21  of the conveyor belt to be joined. 
     Moreover, at the lower plate  11  guides  25  are provided for connecting a membrane  26  which defines the pneumatic pusher pad in cooperation with the lower plate, this solution replacing the use of the classic pad  3  which acts between the lower plate  11  and the heating plate  2 . In greater detail, the heating plate  2  has an outer face  30  which is substantially flat and is flanked by a heating resistor  31 , positioned by means of a spacing insulator  32 , which optionally can also be of the type which is directly integrated in the resistor. 
     The spacing insulator  32  is retained in position by means of an insulating body  33 , which has a structural function for supporting the heating plate and is provided laterally with lips  34  which protrude with respect to the plate and are positioned so that said body  33  can be retained by the wings  12  defined by the extruded body which constitutes the reaction beam. 
     The assembly is further completed by a thermocouple  36 , which adjusts the temperature, and ducts  38  for circulating cooling water are positioned on the longitudinal edges of the heating plate. 
     With this arrangement, the heating plate and the corresponding insulating body can be inserted without having to use screws. 
     Moreover, the longitudinal movement coupling between the reaction beam and the heating plate is provided by means of pins  40 , one for each side, which enter the threaded seat  41  defined by a block  42  which can be accommodated within the outer seat  20  defined by the profiled element; the pin intersects the lips  34  of the insulating body  33 , thus allowing to lock the relative longitudinal sliding between the reaction beam and the heating plate, leaving the possibility of free expansion of the heating plate when it is heated. 
     From what has been described above it can thus be seen that the invention achieves the proposed aim and objects, and in particular the fact is stressed that by providing the reaction beam by means of an extruded element provided with seats for detachable insertion of reinforcement elements, it is possible to have a single constructive element which in each instance is reinforced by introducing reinforcement elements  16  according to the different lengths, maintaining always the same shape with the consequent possibility to achieve very low weights for the assembly. 
     Another important aspect further consists in that the structure thus provided allows to simplify considerably the connection of the heating plate. 
     The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. 
     All the details may further be replaced with other technically equivalent elements. 
     In practice, the materials used, as well as the contingent shapes and dimensions, may be any according to requirements. 
     The disclosures in Italian Patent Application No. MI2006A002377 from which this application claims priority are incorporated herein by reference.