Abstract:
The present invention relates to a moulding machine ( 1 ) for producing flaskless moulds. The moulding machine ( 1 ) comprises a drag flask ( 3 ) and a cope flask ( 2 ), a drag squeeze plate ( 6 ) associated with said drag flask ( 3 ), and a cope squeeze plate ( 5 ) inserted in said cope flask ( 2 ), all arranged to be rotated between a horizontal and a vertical position and the drag flask ( 3 ) and cope flask ( 2 ) being arranged to be movable relative towards one another and away from one another. The drag flask ( 3 ), the cope flask ( 2 ), the drag squeeze plate ( 6 ), and the cope squeeze plate ( 5 ) are guided in their relative movement by a common set of guide rods ( 7 ), whereby the alignment procedure for these components is significantly facilitated.

Description:
TECHNICAL FIELD 
     The present invention relates to a machine for producing flaskless moulds of the kind set forth in the preamble of claim  1 . 
     BACKGROUND ART 
     Document EP 1,161,319 discloses a mould-forming machine of the above-mentioned type. This moulding machine is of a type in which a cope flask, a pattern plate and a drag flask are capable of rotating over an angle of 90° between a horizontal position and a vertical position. The horizontal position is associated with inserting the pattern plate between the cope and drag flask before the sand charging and compacting step and is associated with the removing of the pattern plate and the discharging of the cope and drag after the charging and compacting step. The sand charging and compacting step is performed with the cope flask, drag flask and pattern plate in the vertical position. The cope flask with the cope flask squeeze plate and the drag flask with the drag flask squeeze plate are supported by a swing frame and rotatable in unison between the horizontal position and the vertical position, and the relative movements of the cope squeeze plate, drag flask and drag squeeze plate are guided by separate guide rods, respectively, whereas the cope flask is held fixedly relative to the swing frame. In this way the alignment function is provided by the swing frame and the guide rods connected thereto, and a separate compression frame is used to transmit the relative large forces related to the compacting of the sand. 
     This construction is relatively complex and the alignment of the individual guide rods for each of the movable components, i.e. drag flask, cope squeeze plate, drag squeeze plate and pattern plate, requires a time-consuming procedure during assembly of the machine. 
     DISCLOSURE OF THE INVENTION 
     Based on this prior art it is the object of the invention to provide a moulding machine of the kind referred to above, with which the complexity is reduced and the alignment procedure is restricted to alignment of only one set of guide rods, said set of rods preferably consisting of two such rods, and these objects are achieved with a moulding machine of said kind, which according to the present invention also comprises the features set forth in the characterizing clause of claim  1 . With this arrangement the complexity and the aligning procedure for the guide rods is simplified and furthermore, the moulding machine can be made relatively compact, requiring only limited space in the production facility. 
     Further advantageous features, the advantages of which will be evident from the following description, are revealed in the sub-ordinate claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the following detailed part of the present description, the invention will be explained in more detail with reference to the exemplary embodiments of the moulding machine for producing flaskless moulds according to the invention shown in the drawings, in which 
         FIG. 1  shows a preferred embodiment of the rotatable part of the moulding machine in accordance with the present invention, 
         FIG. 2  shows the same part of the machine seen from the side, 
         FIG. 3  shows a cross section along the lines III-III in  FIG. 2 , 
         FIG. 4  shows a perspective view of a preferred embodiment of the moulding machine in a position ready for rotation, with the pattern plate positioned between the cope flask and the drag flask and the cope squeeze plate and drag squeeze plate in a position to define the mould-forming chambers, all positioned in the horizontal position, 
         FIG. 5  shows the moulding machine with the rotatable part rotated to the vertical position ready for sand charging, 
         FIG. 6  shows the moulding machine returned to the horizontal position and opened in order to be able to remove the pattern plate, 
         FIG. 7  shows the moulding machine with the pattern plate removed, and still in the open position to allow possible insertion of cores in the mould, 
         FIG. 8  shows the moulding machine in a position where the cope and drag flasks are brought into contact with one another ready for removing the finished mould parts, 
         FIG. 9  shows the moulding machine in a position where the mould parts have been expelled from the cope flask and drag flask, resting on the drag squeeze plate, 
         FIG. 10  shows the moulding machine in a position, in which the drag squeeze plate has been rotated about a vertical axis and with the expelling arm tilted to allow this rotation, 
         FIG. 11  shows the moulding machine with the expelling arm returned to the horizontal position ready for expelling the finished mould parts, and 
         FIG. 12  shows the moulding machine with the finished mould parts expelled to the side of the machine. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The machine for producing flaskless moulds shown in  FIG. 4  is provided with a base frame  15  which carries the other components of the machine. The machine comprises a rotatable part shown in  FIGS. 1-3 , rotatably mounted to the base frame  15  through bearings  12  associated with the cope flask  2 . In the  FIGS. 4-12  part of the frame  15  is cut away in order to be able to see the essential parts of the machine. A piston cylinder unit  13  is connected between the frame  15  and a connection point  14  associated with the cope flask  2 , the connection point  14  for the piston cylinder unit  13  being positioned at a suitable distance from the bearing  12  for providing the rotational movement. 
     As best shown in  FIG. 3 , the cope flask  2  is provided with linear bearings  20  for the guide rods  7 , thus rotating with the rotation of the cope flask  2 . At the upper end of the guide rods  7 , a yoke  8  is connected between the upper ends of the two guide rods  7 , said yoke  8  supporting a pressure cylinder  9 , the piston rod of which is connected to the cope squeeze plate  5  for compacting the sand moulds. 
     A drag flask  3  is disposed below the cope flask  2  and connected to the guide rods  7  by means of linear bearings  21  to allow a linear movement along these guide rods  7 . Furthermore, the drag squeeze plate  6  is connected to a yoke  35  with a set of linear bearings  22  for linear movement along the guide rods  7 . 
     When the rotatable system is in the vertical position, as shown in  FIG. 5 , a set of stays  10 , only one shown in  FIGS. 1 and 3 , are positioned as shown in  FIG. 1  and  FIG. 3 . In this position, the compacting of the sand is provided by means of the pressure cylinder  9  moving the cope squeeze plate  5  into the cope flask  2  and the yoke  8  and the guide rods  7  in the opposite direction, whereby the stays  10  engage the yokes  11  and a corresponding engagement point on the linear bearing  22  for the drag squeeze plate  6 , thus moving the drag squeeze plate  6  into the drag flask  3 , hence compacting the sand inside the cope flask  2  and the drag flask  3  around the pattern plate  4  which is inserted between those two flasks. 
     The pattern plate  4  can be moved in and out of the interspace between the cope flask  2  and the drag flask  3  by means of a pattern-plate-moving mechanism  19  comprising rails  28  for providing horizontal movement of the pattern plate  4 , said rails  28  being connected to piston cylinder units  26   b  for this movement, and said pattern-plate-moving mechanism  19  further being connected to the cope flask  2  via guide rods  27  providing the possibility of moving the pattern plate in a direction along the guide rods  7  by means of a piston cylinder unit  26   a  connected between the pattern-plate-moving mechanism  19  and the cope flask  2 . The pattern-plate-moving mechanism  19  comprises suitable means for engaging and supporting the pattern plate  4  when moved in and out of the interspace between the cope flask  2  and the drag flask  3 , and for disengaging the pattern plate  4 , when held in position between the cope flask  2  and the drag flask  3 . 
     The drag squeeze plate  6  is connected to the linear bearings  22  for the drag squeeze plate via a pivotal mechanism pivoting on a bearing  31  as said pivotal movement being provided by means of a piston cylinder unit  30 , said pivotal movement moving the drag squeeze plate  6  between the normal position for co-operating with the drag flask  3  to a position as shown in  FIG. 10  and  FIG. 11  for discharging the produced flaskless moulds sideways out of the moulding machine  1 . The discharge of the produced flaskless mould is provided by means of an expelling mechanism  18  comprising an expelling arm  32  being pivotal between a horizontal and a vertical position by means of a piston cylinder unit  33  and movable between a position inside the moulding machine  1  to a position outside the moulding machine  1  by means of a piston cylinder unit  34 . 
     The correct positioning of the cope squeeze plate  5  relative to the cope flask  2  is provided by means of a piston cylinder unit  23  connected between the cope flask  2  and the yoke  8 , thus positioning the cope squeeze plate  5 , the yoke  8  and the guide rods  7  relative to the cope flask. Correspondingly, a piston cylinder unit  24  is connected between the cope flask  2  and the drag flask  3  for positioning of the drag flask and a piston cylinder unit  25  is connected between the cope flask  2  and the drag squeeze plate  6  for positioning thereof. 
     A sand-charging system  16  is provided for charging sand into the cope flask  2  and the drag flask  3  through sand-charging openings  29  in the cope and drag flasks, said sand-charging openings  29  being connected to the sand-charging system  16  when the rotatable part of the machine is in the vertical position as shown in  FIG. 5 . 
     The production process of moulding a flaskless mould comprising two mould halves with the machine according to the invention will now be described with reference to  FIGS. 4-12 . 
     The sequence of operations starts in the state shown in  FIG. 4  with the flasks in a horizontal position and with the pattern plate  4  inserted between the cope flask  2  and the drag flask  3 . Furthermore, the cope squeeze plate  5  and the drag squeeze plate  6  are inserted in the cope flask  2  and the drag flask  3 , respectively, thus defining the mould chambers inside the flasks. In the next step, the rotatable system is rotated over 90° from the horizontal position to the vertical position by the hydraulic cylinder  13 , as shown in  FIG. 5 . The sand-charging system  16  is now connected to the sand-charging openings  29  of the respective flask. In the following step, still in the position as shown in  FIG. 5 , the mould-half-forming spaces in the cope flask  2  and the drag flask  3  are filled with sand by supplying sand from the sand-charging system  16 . 
     Then, the charged sand is compacted by the cope squeeze plate  5  and the drag squeeze plate  6  being forced further into the cope flask  2  and the drag flask  3 , respectively. This compaction is provided by means of the pressure cylinder  9 , as described previously. As a result, a cope and drag are moulded by compression in the cope flask  2  and the drag flask  3 . 
     After completion of the squeezing, the rotatable part of the machine is rotated over 90° back from the vertical position to its starting position, in which the cope flask  2  and the drag flask  3  take their horizontal position, essentially as shown in  FIG. 4 . In a next step, the drag flask  3  and the squeeze plate  6  are lowered in unison and the pattern plate  4  is lowered to take a position in between the cope flask  2  and the drag flask  3 , as shown in  FIG. 6 , causing the pattern plate  4  to separate from the cope flask  2  by being lowered while resting on the drag flask  3  until the pattern-plate-moving mechanism  19  engages the pattern plate  4 , causing the pattern plate  4  to separate from the drag flask  3 . In the next step, the pattern plate  4  is retracted from the space between the cope flask  2  and the drag flask  3  by the hydraulic cylinder  26   b  and moved upwards by the hydraulic cylinder  26   a  to the position shown in  FIG. 7 . The drag flask  3  and the drag squeeze plate  6  are raised in unison until the upper surface of the drag flask  3  is in contact with the lower surface of the cope flask  2 , causing the mould surface of the cope to be brought into contact with the mould surface of the drag. Thus, the cope and drag are superposed, as shown in  FIG. 8 . 
     Thereafter, the cope squeeze plate  5  is lowered by the piston cylinder unit  23  to separate the cope and drag from the cope flask  2  and drag flask  3 . The drag squeeze plate  6  is simultaneously lowered by the piston cylinder unit  25 , and the drag squeeze plate  6  serves as a table for the mould package  36  consisting of the superposed cope and drag moulds and moves the mould package  36  downwards to a position as shown in  FIG. 9 . 
     Following this, an expelling arm  32  is tilted to the position shown in  FIG. 10  by a piston cylinder unit  33 , and the drag squeeze plate  6  is rotated to the position shown in  FIG. 10 , said rotation being provided by the piston cylinder unit  30  turning the drag squeeze plate about a bearing  31  associated with the drag squeeze plate  6 . After this turning movement, the expelling arm  32  is turned back to the position shown in  FIG. 11  by the piston cylinder unit  33 , whereupon the piston cylinder unit  34  is activated to expel the mould package  36  to a position to the side of the mould-forming machine, as shown in  FIG. 12 , in which position the mould package  36  can be transported further on to a pouring unit on a separate transport system for this purpose. 
     Following this or at a later time before delivery of the next moulds, the expelling arm  32  is brought back to its starting position and the drag squeeze plate  6  is turned back into alignment with the drag flask  3 , whereupon the drag flask  3  is lowered to allow insertion of the pattern plate  4  between the cope flask  2  and the drag flask  3 , after which the drag flask  3 , the drag squeeze plate  6  and the pattern plate  4  are brought to the position shown in  FIG. 4  ready for a new cycle for the moulding machine. 
     The machine has now reached its starting position and is ready for producing the next mould as a part of a cycle operation, which is repeated for mass production of flaskless moulds. 
     Although the above described embodiment has been explained in detail, a man skilled in the art will be able to provide several deviations therefrom without departing from the scope of the following claims. Such deviations comprise e.g. 
     alternative positions of the bearings  12  to e.g. be associated with the drag flask  3 , alternative position of the pressure cylinder  9  to e.g. be connected to the drag squeeze plate  6 , use of other moving mechanisms than the described hydraulic cylinders for providing the relative movements of the different components, such as e.g. pneumatic cylinders or electric linear drives, etc. 
     LIST OF REFERENCE NUMERALS 
     
         
           1  Mould-forming machine for producing flaskless moulds 
           2  Cope flask 
           3  Drag flask 
           4  Pattern plate (match plate) 
           5  Cope squeeze plate 
           6  Drag squeeze plate 
           7  Guide rods 
           8  Yoke connecting the guide rods  7  and supporting the pressure cylinder  9   
           9  Pressure cylinder for compacting the sand moulds 
           10  Stays 
           11  Yokes on ends of guide rods  7  for engaging the stays  10   
           12  Bearing for rotational movement of the rotatable system 
           13  Piston cylinder unit for rotational movement 
           14  Connection for piston cylinder unit  13   
           15  Frame 
           16  Sand-charging system 
           17  Axis for rotational movement of rotatable system 
           18  Expelling mechanism 
           19  Pattern-plate-moving mechanism 
           20  Linear bearings for cope flask 
           21  Linear bearings for drag flask 
           22  Linear bearings for drag squeeze plate 
           23  Piston cylinder unit for relative movement of cope squeeze plate 
           24  Piston cylinder unit for relative movement of drag flask 
           25  Piston cylinder unit for relative movement of drag squeeze plate 
           26   a,b  Piston cylinder units for relative movement of pattern plate 
           27  Guide rods for pattern-plate-moving mechanism  19   
           28  Rails for pattern-plate-moving mechanism  19   
           29  Sand-charging openings 
           30  Piston cylinder unit for rotational movement of drag squeeze plate 
           31  Bearing for rotational movement of drag squeeze plate 
           32  Expelling arm 
           33  Piston cylinder unit for tilting expelling arm  32   
           34  Piston cylinder unit for moving expelling arm  32  to expel the produced superposed cope and drag 
           35  Yoke for drag squeeze plate  6   
           36  Mould package