Abstract:
Disclosed is a mold-closing device for an injection molding machine used for processing plastic materials, in which the mold supports accommodating an injection mold therebetween and a support element ( 13 ) for a mold-closing mechanism (C) are mounted on the machine base ( 14 ). In order to be able to precisely align the mold supports, the first mold support is also mounted on the machine base ( 14 ) so as to be movable in the closing direction, the support element ( 13 ) is mounted on the machine base ( 14 ) or a part thereof via a stationary bearing, and a positioning mechanism ( 16 ) is provided for adjusting the angle between the support element ( 13 ) and the machine base ( 14 ).

Description:
REFERENCE TO RELATED APPLICATIONS 
   The present application claims the priority of German Patent Application 103 09 906.9, filed on Feb. 25, 2003, the disclosure content of which is hereby incorporated by reference in its entirety. 
   FIELD OF THE INVENTION 
   The invention relates to a mould closing unit for an injection molding machine for processing of plastics materials and other plasticizable substances such as ceramic or pulverulent substances in accordance with the preamble of claim  1 . 
   BRIEF DESCRIPTION OF RELATED ART 
   The conventional design of a plastics material injection molding machine, as underlies the preamble of claim  1 , is made known in EP 1 121 237 B1 or DE 21 33 540 A. In the case of this type of injection molding machine, a stationary mould carrier is provided and it is fixedly secured to the machine base. A closing mechanism supported on a supporting member moves a movable mould carrier towards this stationary mould carrier and away from this stationary mould carrier in a cyclical manner and thereby closes the injection mould accommodated between the mould carriers. On the injection molding side, an injection molding unit abuts against the stationary mould carrier in order to inject plasticizable material into the mould cavity through an opening of the stationary mould carrier. The angular alignment and also the longitudinal alignment of the machine on the machine base are oriented on the stationary mould carrier. When the closing pressure is built up, the braces interconnecting the mould carriers are forcibly extended. This brace extension leads to a displacement of the supporting member in horizontal direction. 
   In principle, during injection molding, a precise mould closure is significant to the quality of the parts produced. In this regard, care must be taken to ensure that the mould carriers are disposed parallel to each other and not at an angle one to the other. The necessary angular perfection can certainly be realized with known injection molding machines, however in existing systems distortions can arise to the parallelogram formed between supporting member, stationary mould carrier and movable mould carrier. These problems occur more especially when the mould closing unit is transferred into a vertical disposition. In this case, the fixed plate can tip due to the base securement and consequently a parallelogram is created. This makes it difficult to adjust the parallelity of the mould carriers and at the same time also makes it difficult to maintain the concentricity of the two centering bores in the mould carriers. 
   SUMMARY OF THE INVENTION 
   Proceeding from this state of the art, the present invention creates a mould closing unit, which enables precise alignment of the mould carriers one relative to the other. 
   The supporting member now becomes the fixed point within the system, which means that even the mould carrier, which up to now has been stationary, is displaceably mounted relative to the machine base. At the same time, the support plate can be secured and adjusted at preferably three points on the machine frame or a part thereof. The angularity of the supporting member can be adjusted by means of the adjusting mechanism. The effect of the brace extension on the “stationary” mould carrier is such that it is displaced in a cyclical manner. However, as the injection molding unit is fixedly connected to this mould carrier, this does not result in any reference problems with regard to the injection molding unit. 
   In a preferred embodiment, a three-point supporting of the supporting member is produced and this enables precise adjustment. This is effective in particular when the mould closing unit has to be transferred into a vertical position or is in this position permanently. Through the three-point supporting of the supporting member, the supporting member is retained at an angle relative to the machine base or to a pivotable bearing element in such a manner that no parallelogram is created. The entire weight of the injection mould and the mould carriers is supported rathermore centrally via the braces on the supporting member. Consequently, optimum parallelity and centricity is guaranteed in this position also. 
   Further advantages are produced from the sub claims and the following description. 

   
     BRIEF DESCRIPTION OF THE FIGURES 
     The invention is described in more detail below by way of the Figures. In which: 
       FIG. 1  is a three-dimensional view of a plastics material injection molding machine including mould closing unit and injection molding unit, 
       FIG. 2  is a representation as in  FIG. 1  with the mould closing unit pivoted into vertical position, 
       FIG. 3  is a three-dimensional view of the machine base with supporting member, 
       FIG. 4  is a representation as in  FIG. 3  with the supporting member pivoted into vertical position, 
     FIGS.  5 , 6  are side views of the representation in  FIGS. 3 and 4 , 
       FIG. 7  is an enlarged, partial cut cutout from  FIG. 6 , 
       FIG. 8  is a top view of the machine base with the mould closing unit removed. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   The invention is now described in more detail as an example with reference to the enclosed drawings. However, the exemplified embodiments are only examples, which are not to restrict the inventive concept to any one specific arrangement. 
     FIGS. 1 and 2  show an injection molding machine for processing plastics materials and other plasticizable substances such as ceramic or pulverulent substances using a mould closing unit F and an injection molding unit S. In  FIG. 2  the mould closing unit that is horizontally disposed in  FIG. 1  is pivoted into a vertical position. The pivoting mechanism  20  necessary to accomplish this will be looked at in detail at a later point. 
   The injection molding machine has a first mould carrier  10 , on which the injection molding unit S is preferably secured. In addition, an additional movable mould carrier  11  is provided which is displaceable relative to the first mould carrier  10  by means of a mould closing mechanism C. Between the mould carriers  10 ,  11  is provided a mould clamping area, in which at least one multiple-part injection mould is receivable between the mould carriers, the parts of the injection mould  12  being detachably secured to the mould carriers  10 ,  11 . A supporting member  13  is provided for the mould closing mechanism C. The mould closing mechanism C is for the cyclical opening and closing of the injection mould  12  with the displacement of the additional movable mould carrier  11  towards the first mould carrier  10  and away from this first mould carrier  10  in the closing direction s-s of the injection mould  12 . 
   Mould closing unit F and injection molding unit S are disposed on a machine base  14  and, where applicable, on a part of the machine base. The first mould carrier  10 , the additional movable mould carrier  11  and the supporting member  13 , in particular, are mounted on the machine base. Force transferring elements, which are provided in the form of braces  18  in the embodiment, absorb the forces occurring between the first mould carrier  10  and the supporting member  13  when the mould is closed and when the plasticizable substances are injected into the injection mould  12 . A U-shaped force transferring element, which allows free access to the mould clamping area, can be provided in place of the braces  18 . 
     FIG. 8  in particular shows that the first mould carrier  10  is also mounted on the machine base or on a part thereof so as to be displaceable in the closing direction s-s. Consequently, both mould carriers are mounted so as to be displaceable in closing direction. The supporting member  13 , contrary to this, is secured via a stationary bearing arrangement at the bearing points  17  on the machine base  14  or on a part thereof, such as, for example, on the bearing element  15 . In addition, an adjusting mechanism  16  ( FIG. 7 ) is provided for adjusting the angle between the supporting member  13  and the machine base  14  or the part of the machine base. According to  FIGS. 7 and 8 , the stationary bearing arrangement of the supporting member  13  on the machine base  14  or a part thereof is spaced from the adjusting mechanism  16  in the closing direction s-s. The stationary bearing arrangement of the supporting member  13  is effected at the bearing points  17 , which are disposed on both sides of a central line m-m and the connecting line therebetween is at right angles to the closing direction s-s. The two bearing points  17  and the adjusting mechanism  16  as the third point consequently form a three-point bearing arrangement, which allows precise adjustment of the supporting member relative to the machine base. The supporting member is preferably produced from one piece, as is known from former patent application DE 102 09 921. According to the solution there, the supporting member itself is also one-piece and compact such that a high level of dimensional accuracy of the supporting surfaces is produced. In principle, however, the adjusting mechanism  16  can also engage another part of the mould closing unit F, which is preferably fixedly connected to the supporting member. 
   Consequently, the three-point bearing arrangement firstly guarantees that, via the bearing points  17 , a disposition at right angles to the central line of the injection molding machine is guaranteed, whilst via the third point, that is to say via the adjusting mechanism  16 , the angularity of the plate is adjustable. The compact supporting member at the same time produces a wide support base, which also meets the demands for vertical operation. The supporting member is stable in itself and no parallelogram is created as the entire weight of injection mould and mould carriers is supported centrally via the four braces  18  relative to the supporting member. Consequently, optimum parallelity and centricity is guaranteed. 
   According to  FIG. 7 , the adjusting mechanism  16  is in the form of a vertical adjusting means for a part of the supporting member  13  spaced from the stationary bearing arrangement. Where applicable, this part can, however, also be an other part of the mould closing unit connected to the supporting member.  FIGS. 2 ,  4 ,  6  and  7  show the disposition of the mould closing unit in the vertical position. In principle, it is also possible to provide a stationary disposition of the supporting member without a pivoting mechanism, however, in the exemplified embodiments the mould closing unit, but at least the supporting member  13 , is mounted on a part of the machine base  14 , a pivotable bearing element  15 . When pivoting, this bearing element  15  enables a transferring at least of the mould closing unit F from a horizontal position of the closing directing s-s into a vertical position. During this pivoting movement, the injection mould unit S can also be pivoted at the same time—as is shown in the embodiment in FIG.  2 —if it is secured to the first mould carrier  10 , however, in principle injection into the separating plane can also be accomplished. 
     FIGS. 3 to 7  show the pivoting mechanism  20 . The bearing element  15  is rotationally displaceable relative to the machine base at the pivotal axis  19 . The pivoting mechanism  20  is mounted at the pivotal axes  22 ,  23  on the supporting member  13  and on the machine base, such that when the pivoting mechanism  20  is actuated, as is represented in  FIGS. 5 and 6 , the transfer from the horizontal position into the vertical position is effected. The supporting member  13  has brace receiving means  21  and at its rear end also bearing means  24 , which come to rest on a bearing face of the machine base  14  during the transfer into the vertical displacement. According to  FIG. 7 , adjustment elements  25  can be provided on the bearing faces  24  in order to adjust the system.  FIG. 7  shows the securement at the bearing points  17  as well as the adjusting mechanism  16  for the supporting member  13 . 
   According to  FIG. 8 , bearing members  26  are provided for the first mould carrier  10  as well as a guiding for the additional, movable mould carrier  11 . These are disposed in the exemplified embodiment on a turntable as bearing element  15 . In principle, however, it is possible to only use the rear part of the bearing element  15 , which bears the actual supporting member  13 , as the mould carriers are guided directly onto corresponding surfaces of the machine base  14 . In the case of a vertical disposition, the supporting is effected anyway via the braces on the supporting member such that further guiding of the mould carriers is not necessary. 
   It is obvious that this description can be subject to the most varied modifications, changes and adaptations which range in the region of equivalents to the attached claims.