Method and device for producing mould material moulds for the casting of metals

Abstract

Methods for improved molds for the casting of metals and to prevent the complexity of the production from increasing are disclosed. “Improved” may be defined such that a mold consisting of the molding material has a surface of uniform hardness, even in the event of a change or variation in the quality of at least one of a plurality of properties of the molding material.

1 . A method for producing a molding-material mold for a cast having a strength for casting of metals, wherein:
 a granular molding material as a molding substance ( 41 ) is filled into a molding box ( 40 );   the molding material ( 41 ) is compacted above a pattern ( 44 ) standing on a pattern plate ( 46 ) within the molding box ( 40 ) in a molding system; wherein:
 in a first step, the molding box ( 40 ) is moved across a first distance by a pressing device ( 1 ) to stop against a frame ( 13 ) of a press head ( 10 ); 
 in a second step, the pattern plate ( 46 ) is moved across a second distance (s 1 , s 2 ) to an end position by the pressing device ( 1 ) for hardening or compacting (creating) the molding-material mold; 
   and wherein the second distance is changed as a function of a determined force at the end of a previous hardening or compacting process of the molding material of a previous mold ( 100 ,  102 ;  102 ′) as a result of a change in at least one property of the non-compacted molding material ( 41 ); or   a length of the second distance is changed as a function of the molding material.   
     
     
         2 . The method according to  claim 1 , wherein a force applied to the molding material ( 41 ) by the pressing device ( 1 ) or the press head ( 10 ) is determined or measured by a sensor ( 30 ) during compaction of the molding material ( 41 ). 
     
     
         3 . The method according to  claim 1 , wherein the applied force is determined or measured by the sensor ( 30 ) and transmitted to a controller ( 100 ), wherein a nominal value or limit values of a nominal range for the applied force are preset in a memory ( 101 ) of the controller ( 100 ), and wherein the measured value is compared to the nominal value or limit values. 
     
     
         4 . The method according to  claim 3 , wherein a deviation is detected by a comparator provided in the controller ( 100 ), and wherein the second distance (s 1 , s 2 ) is changed (Δs) as a result thereof. 
     
     
         5 . The method according to  claim 3 , wherein a program calculates a correction value from the determined deviation, the correction value is converted into a signal by the controller ( 100 ), and the signal is output to an actuator ( 20 ) which changes a length of the second distance. 
     
     
         6 . The method according to  claim 1 , wherein the stored value is a predetermined or pre-determinable value. 
     
     
         7 . The method according to  claim 1 , wherein the determined force value is detected by the sensor ( 30 ) during compaction of a preceding molding-material mold, especially the molding-material mold created immediately prior to the current compaction and measured subsequently thereto. 
     
     
         8 . The method according to  claim 1 , wherein the comparative value is detected during creation of the previous molding-material mold ( 90 ), especially immediately prior to the current compaction. 
     
     
         9 . The method according to  claim 1 , wherein the change in length of distance is determined as a function of the calculated correction value. 
     
     
         10 . The method according to  claim 3 , wherein a correction value is determined from the detected deviation, which correction value is, in particular, proportional to the deviation, and wherein the correction value is converted into a signal by the controller ( 100 ), which signal is output to an actuator ( 20 ) which changes a length of the second distance; wherein the deviation is one of:
 a non-achievement of the nominal range, i.e. is outside of the nominal range;   a shortfall of the target value of the force as a nominal value; and   an exceedance of a target value of the force as nominal value.   
     
     
         11 . The method according to  claim 1 , wherein a detected deviation of a measured ( 30 ) or determined force at the end of the current compaction process from a desired force as a representative of strength causes the following control direction:
 if the measured force is too high, the second distance (s 1 , s 2 ) is decreased; or   if the measured force is too low, the second distance (s 1 , s 2 ) is increased;   especially proportionally to the previously detected deviation in each case.   
     
     
         12 . The method according to  claim 1 , wherein a time range is spanned at the end of the hardening or compacting process, which ranges from the time of the end of compaction, when the lower edge ( 40   a ) of the molding box ( 40 ) is reached, to at most the duration of the molding cycle or sampling cycle of the control (T), since no or no noticeable change in mold hardness occurs within this range. 
     
     
         13 . The method according to  claim 1 , wherein a changed force-distance characteristic of the currently compacted molding material ( 41 ) is compensated or balanced by the change in distance of the pattern plate ( 46 ) from a lower edge of the molding box ( 40 ) as compared to the force-distance characteristic of the molding material ( 41 ) that was compacted more than one compaction process earlier, even though it is supposed to be the same molding material. 
     
     
         14 . The method according to  claim 1 , wherein the force-distance characteristic of the preceding, i.e. immediately preceding compaction process is used in the change in distance of the pattern plate ( 46 ) from a lower edge of the molding box ( 40 ) for the force-distance characteristic of the currently compacted molding material ( 41 ). 
     
     
         15 . A molding system for casting molds for the casting of metals, the system comprising:
 a linearly movable pressing device for exerting pressure on the mold being created which includes a pattern ( 44 ) and a pattern plate ( 46 ) carrying this pattern, a molding box ( 40 ) for the casting mold and a filling frame ( 42 ) for receiving an upper portion of a molding material ( 41 ) for the mold;   a press head ( 10 ) including at least one mold stamp ( 11 );   an actuator ( 20 ) being coupled to the pressing device or the molding box and including a linear drive that is decoupled from a drive of the pressing device;   a force sensor ( 30 ,  90 ) for measuring a force applied to or exerted on the molding material ( 41 ) by the pressing device or the press head ( 10 );   a controller ( 100 ,  102 ), wherein a distance (s 1 ) between the pressing device and the molding box can be adjusted by the controller ( 100 ) via the actuator ( 20 ), when the molding box abuts the press head or a frame of the press head.   
     
     
         16 . (canceled) 
     
     
         17 . The molding system according to  claim 15 , wherein the press head ( 10 ) comprises a plurality of parallel mold stamps ( 11 ). 
     
     
         18 . The molding system according to  claim 15 , wherein the adjustment of the distance (s 1 ) is carried out before the pattern plate ( 46 ) can be moved upwards by the pressing device. 
     
     
         19 . The molding system according to  claim 15 , wherein the force sensor ( 30 ) is configured such that it detects a force value during compaction of a preceding molding-material mold, especially the molding-material mold created immediately prior to the current compaction. 
     
     
         20 . A method for producing a force-controlled molding-material mold suitable for a cast metal, the molding-material mold having a predetermined or pre-determinable minimum strength at, at least, the surface thereof receiving the cast metal, wherein:
 a compactible molding material ( 41 ) is filled into a box stack including a molding box ( 40 );   the molding material ( 41 ) is compacted within the box stack above a pattern ( 44 ) standing on a pattern plate ( 46 ) which initially has a distance (s 1 ) from a lower edge of the molding box ( 40 ), wherein:
 the box stack, together with the pattern plate, is moved across a first distance by a pressing device ( 1 ) for initially compacting the molding material ( 41 ); 
 a changed second distance (s 2 ) is adjusted instead of the first distance as a function of a detected or determined force (F 2 ) at the end of a compaction process of one of the preceding compaction processes; 
 the pattern plate ( 46 ) is moved relative to the molding box ( 40 ) across the changed second distance (s 2 ) to an end position by the pressing device ( 1 ) for a second compaction and creation of the molding-material mold. 
   
     
     
         21 . The method according to  claim 20 , wherein the molding-material mold is a mold half. 
     
     
         22 . The method according to  claim 20 , wherein the second distance (s 2 ) for the subsequent compaction process is changed as a function of the detected or determined force (F 2 ) at the end of the compaction process preceding in time. 
     
     
         23 . (canceled) 
     
     
         24 . The method according to  claim 20 , wherein the press head ( 10 ) comprises a plurality of mold stamps ( 11 ). 
     
     
         25 . The method according to  claim 20 , wherein the initial adjustment of the distance (s 1 ) is carried out before the pattern plate ( 46 ) can be moved upwards by the pressing device. 
     
     
         26 . A method for producing a molding-material mold for a cast having a minimum strength for the casting of metals, wherein:
 a granular molding material as a molding substance ( 41 ) is filled into a molding box ( 40 );   the molding material ( 41 ) is compacted above a pattern ( 44 ) standing on a pattern plate ( 46 ) within the molding box ( 40 ) in a molding system; wherein:
 in a first step, the molding box ( 40 ) is moved across a first distance by a pressing device ( 1 ) to stop against a frame ( 13 ) of a press head ( 10 ); 
 in a second step, the pattern plate ( 46 ) is moved relative to the molding box ( 40 ) across a second distance (s 1 , s 2 ) to an end position by the pressing device ( 1 ) for hardening or compacting (creating) the molding-material mold; 
   and wherein the second distance (s 1 , s 2 ) is changed as a function of a determined force at the end of a previous hardening or compacting process of the molding material of a previous mold ( 100 ,  102 ;  102 ′) as a result of a change in at least one property of the non-compacted molding material ( 41 ).   
     
     
         27 . The method according to  claim 1 , wherein a force applied to the molding material ( 41 ) by the pressing device ( 1 ) or the press head ( 10 ) is determined by a sensor ( 30 ) during compaction of the molding material ( 41 ). 
     
     
         28 . The method according to  claim 27 , wherein the applied force is determined or measured by the sensor ( 30 ) and transmitted to a controller ( 100 ), wherein a nominal value or limit values of a nominal range for the applied force are preset in a memory ( 101 ) of the controller ( 100 ), and wherein the measured value is compared to the nominal value or limit values. 
     
     
         29 . The method according to  claim 26 , wherein a correction value is calculated from the determined deviation, the correction value is converted into a signal by the controller ( 100 ), and the signal is output to an actuator ( 20 ) which changes a length of the second distance (s 2 ). 
     
     
         30 . The method according to  claim 26 , wherein a detected deviation of a measured ( 30 ) or determined force at the end of a current compaction process from a desired force as a representative of strength causes the following control direction:
 if the measured force is too high, the second distance (s 1 , s 2 ) is decreased; or   if the measured force is too low, the second distance (s 1 , s 2 )  15  increased;   
     
     
         31 . The method according to  claim 30 , wherein the second distance is changed proportionally to the previously detected deviation in each case. 
     
     
         32 . The method of  claim 27 , wherein the determination is done at the end of the compaction process. 
     
     
         33 . The method of  claim 9 , wherein the distance is reduced when the detected force is too high.