Abstract:
The present invention relates to an apparatus for the production of window frames made of profile sections with a joining device in which the profile sections are joined into window frames and with a conveying device for the supply of profile sections to the joining device. A substantially automated production is achieved in such a way that the joining device is in connection with an insertion device which is provided upstream with at least one turning device in order to turn the profile sections into the respective position and that the insertion device is arranged so as to convey the profile sections to an insertion position on the joining device in a configuration corresponding to the completed window frame.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to an apparatus for producing window frames from profile sections, with a joining device in which the profiles are joined into window frames and with a conveying device for supplying the profile sections to the joining device. 
     Window frames are merely produced in an automated manner from respective profiles. Within the terms of the present invention the term “window frame” shall mean both the generally movable arranged component which carries the window pane so as to form a wing of a window as well as the component fixedly arranged in the building in which one or several wings of windows are arranged. In the case of plastic windows, the joining device is arranged as a welding machine which at first heats the ends of the profile section which are cut to mitre and then presses them against one another in order to bring about a fixed connection. Metal windows can be produced in such a way that a respective connection part made of plastic or the like is introduced into the hollow spaces of the metal profiles at the ends cut to mitre, whereupon a predetermined zone of the metal profile is plastically deformed by a die in order to ensure a secure connection to the metal profile sections with the fixing parts. 
     The insertion of the profile sections into the respective joining device is generally made manually. The profile sections that belong to one another are conveyed into the vicinity of the joining device, whereupon an operator performs the insertion process. As a result of high need for staff, this procedure is expensive and very inefficient. As an alternative, it is possible to have the insertion of the profile sections into the joining device performed by a machine, namely by a buckling arm robot. However, the cycle time of modern joining devices is so short that it is not possible for such a rotor to insert four profile sections in the available time. That is why the robot becomes a capacity-limiting component. 
     DESCRIPTION OF PRIOR ART 
     From DE 37 21 861 A a method and apparatus for the production of a rectangular frame, in particular a window frame, has become known. In this method the plastic profile pieces which are cut to size are deposited into an intermediate storage for each frame so as to be taken from there individually by a gripper movable in three planes and so be deposited successively in the welding machine. In respect of magnitude, the duration of the insertion process corresponds to that of the actual welding process, i.e. the welding machine is utilized in such a case only with half of its theoretically possible capacity. 
     From DE 38 31 471 A a method for the production of plastic windows is known in which a capacity increase is achieved in such a way that a window frame profile and a wing profile are simultaneously extruded from a tool, cut and welded. The problem of insertion into the welding machine has also not been solved in the this known method. 
     An arrangement for the production of corner joints in window and door frames is also known from DE 23 54 233. The joining of the corner is substantially performed on a mounting table. The problem of an efficient insertion of the profile sections is also not mentioned here. 
     SUMMARY OF THE INVENTION 
     It is the object of the present invention to improve the aforementioned apparatus in such a way that an increase in performance can be achieved with the smallest possible expenditure. 
     This object is achieved in accordance with the invention in such a way that the joining device is in connection with an insertion device which is provided upstream with at least one turning device in order to turn the profile sections into the respective position and that the insertion device is arranged so as to transport the profile sections in a configuration corresponding to the completed window frame into an insertion position on the joining device. 
     The relevant aspect in the present invention is that the profile sections which are all conveyed in the same orientation are turned by the insertion device into the respectively required position. A turning device within the terms of the present invention is generally understood as being a component which can grip the respective profile section and turn it respectively. In accordance with the invention the individual profile sections are brought prior to the insertion to a position which corresponds principally to the completed frame. Depending on the employed joining method, there can still be spaces between the sections to be joined. For example, if the joining is performed by a four-head welding machine, the surface areas which are cut to mitre are present at a distance which allows the introduction of a welding mirror. 
     The present invention can be applied to different types of windows. In the production of plastic windows the joining of the profile section occurs in the known manner by welding. A pressing process is usually employed for alumina profiles. Gluing or nailing can additionally be performed for composite profiles having a wood portion. 
     A further increase in the cycle time can be achieved in such a way that the insertion device is provided with two turning devices which can be operated independent from one another. It is particularly favourable if one turning device is arranged for the rotation of a profile section by 180°, whereas the other turning device is arranged for turning profile sections by 90° clockwise in one direction and counterclockwise in another direction. In such an embodiment the production of the profile sections is favourably programmed in such a way that alternatingly horizontal and vertical profile sections are conveyed to the joining device. In this way the turning device is used for turning by 180° only every fourth profile section, whereas the other turning device will come into action for turning by 90° every second profile section. It is ensured in this way that the work speed of the turning device is no limiting factor for the capacity of the installation. 
     In an especially preferable embodiment of the invention it is provided that several feed devices are provided which each supply one or several joining devices with profile sections. In this way cycle times and production capacities of the extrusion lines can optimally be matched to one another in such a way that maximum throughput is achieved. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     The invention is now explained below in closer detail by reference to the embodiments shown in the drawings, in which: 
     FIG. 1 shows an overview of a production line for the production of windows with apparatuses in accordance with the invention; 
     FIG. 2 shows a detail of FIG. 1 on an enlarged scale and 
     FIG. 3 shows a further detail of FIG. 1 on an enlarged scale. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The production unit of FIG. 1 is provided for the production of double-wing windows. The first production line  1  is used for producing frames to be fixedly installed in buildings, whereas the product line  2 , which branches at its end into lines  2   a  and  2   b,  is used for the production of window wings  3   a,    3   b.  In an extrusion line which is generally known and is not shown herein, profile bars are produced for the frames and windows to be manufactured. A conveying device  4  for the frames, and conveying devices  5   a,    5   b  and  6  for the wings  3   a,    3   b  convey the bars to the mitre-box saws  7 ,  8   a,    8   b  and  9 . The window wings  3   a,    3   b  are arranged in such a way that they each consist of three narrow profile sections and a wide profile section. The conveying device  6  with the mitre-box saw  9  is used for supplying the wide profile sections for both wings  3   a,    3   b.  The conveying device  5   a  with the mitre-box saw  8   a  is used for delivering and producing the profile sections for the first window wing  3   a,  whereas the conveying device  5   b  with the mitre-box saw  8   b  is used for supplying and manufacturing the narrow profile sections for the second window frame  3   b.  A machining station  10  in the first production line  1  is used to manufacture the required bores, grooves and the like. 
     The actual production of the frames in the production line  1  occurs in a section which comprises a conveying device  11 , an insertion device  12  which can be extended by additional mounting devices such as the additional mounting of corner connectors  12   a  for example, an additional device  12   b  for the application of sealing media or glues (e.g. for composite wood windows) consisting of the components  12   c   1  for the insertion of the traverse pair of bars as well as of  12   c   2  and  12   c   3  for inserting the lengthwise bars, and which is provided with a joining device  13  which is arranged as a pressing apparatus. This section of the production line  1  is shown in FIG. 2 on an enlarged scale and will be explained on the basis of this figure in closer detail. The production line  2  comprises a common conveying device  14  which is supplied with profile sections by the mitre-box saws  8   a,    8   b  and  9 . The insertion devices  15   a,    15   b  (consisting of the mounting devices  15   a   1 ,  15   b   1  for the corner connectors for example and the actual insertion devices  15   a   2 ,  15   bs ) and joining devices  16   a,    16   b  of the production lines  2   a,    2   b  for the production of the window wings  3   a,    3   b  are each provided with a separate arrangement. This section of the production line  2  is shown in detail in FIG. 3 on an enlarged scale and will be explained in closer detail in connection with this figure. 
     FIG. 2 shows a part of the production line  1  on an enlarged scale. A buffer storage means  17  is provided so as to enable an optimization of wastage. It is relevant for the progress of the production of the frames or wings that the individual profile sections are delivered in a precisely defined sequence. If these profile sections are cut from bars of six meters length, optimization of wastage is no longer possible. As a result of using a buffer storage means, profile sections can be produced from bars of six meters length by minimizing waste, with a resorting occurring in the buffer storage means  17  in such a way that subsequently the correct sequence is produced again. The sorting device can be extended by an additional device  17   a  in order to perform mounting processes on the single bar for example (such as the automated joining of aluminium and wood in wood and aluminium composite windows, the automated insertion of reinforcing profiles in PVC windows and the screwing in of the reinforcing profile). The profile sections are placed on a middle conveying path  18  and moved in a cycled manner to the left in FIG. 2. A first cross belt  19  will take over every fourth profile section in order to place the same on a second conveying path  20  which is parallel to the first conveying path  18 . The cross belt  19  is equipped with a turning device  21  which turns the respective profile section by 180°. In this way the individual profile sections already have the correct orientation on the second conveying path  20  in order to form the upper part of the frame. A further cross belt  22  removes the profile sections in order to place them on a further conveying path  23  which is also parallel to the conveying path  18 . A further turning device  24  is provided on the conveying path  18  downstream of the cross belts  19  and  22 , which turning device turns the profile sections on the conveying path  18  alternatingly clockwise and counterclockwise. The insertion device  12  where the profiles from the conveying paths  18 ,  20  and  23  are supplied to thus contains all profile sections already in the correct orientation. The insertion device  12   c  is used to simultaneously insert, in one work pass, the four profile sections in the correct position into the joining device  13 . Corner connectors are inserted into the end of the profile sections in this joining device  13  which is arranged for aluminium profiles, which connectors form the joining elements. The aluminium profiles are squashed in the joining device  13  in order to thus produce a stable and permanent connection. Such a joining device is principally known. Plastic profiles can be treated in an analog manner, with the connection being made by welding at the edges cut to mitre. 
     The present machine is controlled by an electronic control device in such a way that the respective first, fifth, ninth, etc. profile section is placed in one row from the cross belt  19  onto the second conveying path  20  by rotation of 180°. The third, seventh, eleventh, etc. profile section is placed by the second cross belt  22  on the further conveying path  23 . The second, sixth, tenth, etc. profile section remains on the first conveying path  18  and is rotated by the second turning device  24  clockwise by 90°. The fourth, eighth, twelfth, etc. profile section also remains on the first conveying path  18  and is turned by the second turning device  24  by 90° counterclockwise. In this way it is possible to achieve high production speeds and short cycle times. 
     FIG. 3 shows that the mitre-box saw  8   a  produces the upper, the left and the right profile section for the window wing  3   a.  The mitre-box saw  8   b  produces the lower, the left and the right profile section for the window wing  3   b.  Saw  9  is arranged as a combined mitre-box and oscillating saw in order to produce the respectively wide profile section for the two window wings  3   a  and  3   b.  A first conveying path  25  is provided for the production of the first window wing  3   a  from which a cross belt  26  takes profile sections in order to place them on a second conveying path  27 . A first turning device  28  turns the respective profile sections by 90° clockwise or counterclockwise. Similarly, a first conveying path  29  is provided for the second window wing  3   b  from which a cross belt  30  takes profile sections in order to place them on a second conveying path  31  which on its part is equipped with a turning device  32 . Additionally, the conveying path  29  is provided downstream of cross belt  30  with a further turning device  33  in order to turn the profile sections by 180°. The wide profile sections are supplied on a conveying path  34 . A cross belt  35 , which is equipped with a turning device  36 , places the profile sections on a conveying path  37  for the first window wing  3   a.  Downstream of the same a cross belt  38  is provided in order to place the profile sections on a conveying path  39  for the second window wing  3   b  while maintaining the orientation of said sections. The profile sections are thus already present in the correct orientation in the insertion devices  15   a,    15   b.  The final production of the window wings  3   a,    3   b  is made in the joining devices  16   a,    16   b,  as has been described above. 
     The arrangement of the apparatuses in this manner allows a production of windows and window frames with extremely short cycles times and substantial automation. In particular, labor-consuming manual insertion processes can be avoided.