US3802487A

US3802487A - Apparatus for producing foundry moulds

Info

Publication number: US3802487A
Application number: US00186156A
Authority: US
Inventors: K Feller
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-10-03
Filing date: 1971-10-04
Publication date: 1974-04-09
Anticipated expiration: 1991-04-09
Also published as: DE2048749A1; FR2112251A3; FR2112251B3

Abstract

An apparatus for producing foundry moulds comprising a machine frame, a flask turntable and a pattern turntable vertically journaled on the machine frame. A flask rests on the flask turntable, and a pattern depends from the pattern turntable. The apparatus is provided with means for placing sand in the flask and has means for rotating the flask turntable and the pattern turntable to position the pattern above the flask. The apparatus also has means for pressing the pattern into the sand while confining the sand to the compartment.

Description

United States Patent 1191 Feller Apr. 9, 1974 APPARATUS FOR PRODUCING FOUNDRY MOULDS [76] Inventor: Kurt W. Feller, lnder Sommeraull,

Zurich, Switzerland 8053 [22] Filed: Oct. 4, 1971 [21] Appl. No.: 186,156

[30] Foreign Application Priority Data Oct. 3, 1970 Germany 2048749 [52] US. Cl. 164/194, 164/37 [51] Int. Cl. B22c 15/02 [58] Field of Search 164/29, 37, 38, 40, 44,

[56] References Cited UNITED STATES PATENTS 3,181,207 5/1965 Schaible 164/181 X 2,752,646 7/1956 Lasater 3,516,475 6/1970 Dougherty 961,702 6/1910 Lewis 1,762,125 6/1930 Perry 164/181 3,029,482 4/1962 Burnett 164/18 2,904,858 9/1959 Pinch0n..... 164/193 X 3,172,173 3/1965 Ellms 164/192 X 3,284,858 11/1966 Taccone 164/171 3,397,737 8/1968 Tuttle 164/339 X 3,618,668 11/1971 Dupre 164/194 Primary Examiner-J. Spencer Overholser Assistant Examiner-John S. Brown Attorney, Agent, or Firm-Otto John Munz [5 7] ABSTRACT An apparatus for producing foundry moulds comprising a machine frame, a flask turntable and a pattern turntable vertically journaled on the machine frame. A flask rests on the flask turntable, and a pattern depends from the pattern turntable. The apparatus is provided with means for placing sand in the flask and has means for rotating the flask turntable and the pattern turntable to position the pattern above the flask. The apparatus also has means for pressing the pattern into the sand while confining the sand to the compartment.

7 Claims, 13 Drawing Figures PMENTEDAPR 9 I924 SHkET 1 [IF 7 TMENTEUAPR 9 I974 3,802,487

sum

5 or 7 FIG. 6

APPARATUS FOR PRODUCING FOUNDRY MOULDS This application relates to a method for making foundry moulds in flasks on automatic turntable moulding machines with multiple work stations, whereby the flask circulation is arranged separately from the pattern circulation and whereby the pattern is compressed from above directly into the sand package.

It is important that automatic moulding units are operated economically with almost full utilization of the mould area and with the possibility of pattern exchange within the cycle time of the unit and besides the pattern circulation, that the machines are also arranged for the alternative possibility to operate with one pattern in the compression station for a number of successive cycles, if necessary.

Multiple station index arm machines as well as turntable machines are known which circulate the flask together with the pattern. Those units have the disadvantage that it is not possible to change the pattern without stopping the machine. Furthermore, it is impossible to change the pattern within the cycle time. Furthermore, it is not possible because of the fixed attachment of flask with pattern to retain one pattern in the compression station for moulding of high series moulds. Furthermore, prior machines produce high series production with one pattern only, requiring melting-and coremaking facilities balanced accordingly. Other prior turntable units permit a pattern circulation but do not permit, within the same arrangement, the indexing of the flask from work station to work station to achieve high production performances with short cycle times.

To avoid those disadvantages, an apparatus and method is provided by this invention, whereby the flask circulation is separated from and is below the pattern circulation. Hereby it is possible, according to a program setting, to direct any desired pattern to any flask. it is even possible for one pattern to remain for a longer period in the compression station to produce a higher series of that particular casting. Furthermore, the arrangement by'this invention is such that patterns not required anymore for castings, can be exchanged for new patterns without stopping the apparatus.

Other prior units include automatic units containing a pattern circulation system. They also allow for exhange of patterns within the cycle time. The disadvantage of those systems is that a gap in the pattern circulation is not permissible and that it is not possible to have such a controlled pattern circulation by which a pattern can remain in the compression station for a number of cycles. This is not possible with those systems since the flasks must pass various work stations while their transporting is done by the indexing of the patterns. Therefore, none of the patterns can remain on the compression station for more than one work cycle. These disadvantages are also overcome by the present invention.

All existing known automatic units for producing moulds in flasks are basically not designed to permit an optimum moulding process. The compressive pressure is applied from above through the sand onto the pattern. Hereby a large portion of the compressive pressure is absorbed by the sand and the flask wall. Therefore, it is proposed by the present invention to arrange the pattern on top with its pattern area directed downwards. The loose sand is compressed from below directly against the pattern and all of the compressive pressure is utilized directly on the pattern surface. Even moulds produced by high pressure hydraulic machines do not reach a satisfactory evenly distributed hardness in the area of the pattern surface, unless a simultaneous jolt compression method is applied. According to the present invention it is therefore further proposed to equalize the different heights of the pattern elevations by different supports on the bottom of the mould through means of equalizing pistons arranged below the sand. In this manner it is possible to adjust the pressure on those equalizing pistons.

At the same time, this compression system permits utilization of the downstroke of the compression unit for the pattern draw operation which is the most advantageous separation procedure of the mould from the pattern. By this method there are no roll-over units required for subsequent handling procedures since the mould halves are already in proper position for core setting in the drag and inspection of the cope. Not one of the units presently available on the market allows the expansion of the installed capacity by adding to the installation, utilizing components already used for the unit, i.e., after the building block concept. Those units are designed and built either for specific pattern sizes in existence, or require new patterns or very expensive pattern changes.

The present invention therefore provides a system permitting fastening of the pattern onto a flat, torsionresistant frame. Pattern segments are just as easily mounted as complete patterns. Also loose patterns made from wood, plastic, metal and plated patterns are easily assembled at relatively low cost onto the flat, torsion-resistant frame.

To satisfy all the requirements necessary for modern moulding techniques, the invention provides a process to produce casting moulds inflasks using automated moulding machines with multiple work stations as summarized in the following.

The necessary work functions for this integrated mould making process are separated into individual stations. After the transfer of an empty flask from a pallet conveyor onto a turntable, the index of the flask from station to station is provided by this turntable. For low and medium capacities, copes and drags are produced in a subsequently changed sequence. For high capacities, two turntable combinations are introduced for the flask index and the mould making, whereby one turntable system is used for the cope moulds and the other for the drag moulds. The turntable system is equipped with one pattern circulation table each and one turntable for sprue drilling circulation and venting fixture circulation.

When practicing the process of the present invention with only one turntable, the copes are separated ahead of the first turntable in a separating station and positioned onto a pallet for the copes. (The pallets for the copes are later returned underneath the core setting conveyor.) The transferred empty flask then is indexed into the sandfill station by the flask turntable. First backing sand and then facing sand are aerated and discharged into the flask. The flask is positioned upon a lower frame which itself is located on the turntable. The turntable and'this frame have an inner opening which is precisely the same as the inner opening of the flask. This opening is closed on the bottom in the sandfill station by a sheetmetal section. This sheetmetal section corresponds directly to the upper surface of the equalizing pistons in the compression station. The sand filled flask is next positioned directly above the equalizing pistons after the index movement. Immediately after the exact positioning, the equalizing pistons are raised first and then the compression cylinder lifts the lift table with the equalizing pistons mounted on it, and by simultaneously vibrating a unit above the pattern is this pressed into the moulding sand. The lift table lifts the lower frame and flask simultaneously and presses those against the upper frame which was brought previously together with the pattern into this position by the turntable. These two mentioned frames and the flask tightly close a room against the outside, and the compressive process takes place without any loss of sand.

The equalizing pistons are actuated by further raising of the lift table. After the desired compressive pressure has been reached, during lifting a pressure relief valve at the equalizing pistons permits the movement of the press cylinder only into the final position, whereby sand, pattern and flask finish with a slight sand projection in accordance with normal moulding practices.

Now the press cylinder and the equalizing pistons move back, first slowly, then fast and draw the flask with the mould down and away from the simultaneously vibrating pattern. The flask is lowered to the turntable and is then indexed with the turntable into a new operating position.

This system has the advantages of the direct compression of the pattern surface into the moulding sand, lowering the flask away from the pattern when drawing the pattern, separation of the operations into sandfill station and compression station, the fixed pattern positioning despite pattern circulation separate from flask circulation, producing large series by retaining the pattern in the compression station and proper positioning the drag for core setting without the necessity of prior drag rollover.

A transfer unit transports the flask into a position in which a milling unit is arranged below for cutting off the bottom of the mould. The flask is then moved onto a drilling circulation turntable. In two successive stations the cutting of the pouring basin and the sprue drilling are accomplished. Depending on the number of cope patterns, a corresponding circulation system operates with the arrangement of different sprue drilling machines.

An additional station is provided for piercing air holes for the mould venting from the top down into the mould. Also, this venting turntable unit corresponds in the number of venting units with the requirements of the different cope patterns; A transfer unit transports the finished mould to a pallet conveyor for further transport through the core setting line. Two of the described units are operated to achieve twice the capacity. In these units the copes are produced on one unit and the drags on the other unit but this one without the facilities for the sprue drilling and the venting turntables.

Here the pallet conveyor for the copes is equipped with a pallet return conveyor. The empty cope flasks in this arrangement are lifted from the empty drag flask by the first transfer unit and transported onto the first turntable for the flask circulation. The cope flask is arranged symmetrically to the center line with bushings to avoid the necessity of a rollover, while the drag is equipped with pins on the parting line and with bushings on the opposite side for proper positioning on the pallets and turntables.

The basic units of the turntables can be used for the flask circulation, pattern circulation and the index movements in the areas of the sprue drilling and venting holes piercing units circulation.

Other turntable units for the sprue drilling and vent hole piercing are easily mountable in operative relationship to the other previously mentioned turntables.

The pallet conveyor can be used either for the combined cope and drag line or for separate cope and drag systems. Therefore it is possible to expand these lines in phases. Spare parts deliveries become a simple matter subject to the establishment of flask size program. Within a standard machine size it is possible to vary flask sizes by reducing or adding of equalizing pistons whereby the lower and upper frames are constructed to have their inner dimensions corresponding to the inner dimensions of the flask.

An automatic pouring unit can be controlled from the program established for the pattern circulation.

Further details and features of the present invention are given in the following description of the drawings which show three preferred embodiments of the possibilities of the process which can be manufactured for the automatic production of casting moulds in flasks after the direct moulding method through the use of multiple station machines, wherein:

FIG. I is a top view showing an embodiment having one multiple station machine group for the alternate moulding of copes and drags for a capacity of approximately 200 complete moulds per hour ready for pour- FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a sectional view taken along line B--B of FIG. 1;

FIG. 4 is a schematic representation of the direct moulding system in the seven basic phases of operation;

FIG. 5 is a top view showing an embodiment having two multiple station machine groups for the moulding of cope and drag moulds each on one of the groups for a capacity of approximately 400 complete moulds per hour ready for pouring;

FIG. 6 is a sectional view taken along the lines CC and DD of FIG. 5; and

FIG. 7 is a top view of an embodiment showing only one multiple station machine for the alternative moulding of cope and drag moulds for a capacity of approximately 100 complete moulds per hour, and ready for pouring and in the stage of a first installation phase with the possibility of expansion by adding same and similar tuntable units to achieve capacities of approximately 200 respectively 400 complete moulds per hour ready for pouring.

Referring now to FIG. 1 there is shown turntables l, 2, 3 with supporting fixtures arranged for example at to each other to perform the cycling index of the flasks counter clockwise as described more completely below.

A return conveyor 4 for empty flasks transports the empty cope flasks 5 and drag flasks 6 automatically and separately to a position 7 in front of the turntable 1 where they are stopped mechanically. A transfer unit 8 (not shown) transports the empty cope flask 5 to the station 9 of the turntable 1.

Further operations take place simultaneously at the operating stations 10, ll, 12, 13, 14, l5, 16 of the turntables 1 and as well as on the operating station 17 of the milling station 18 shown in FIG. 2 which are described in the following with the sequence of the example of the cope flask 5. 1

After the cope flask 5 has been set down on station 9, the turntable 1 indexes the cope flask 5 to station 10. A special measuring sand hopper 19c, as shown in FIG. 2 and as described later, discharges first back-up sand 19a and subsequently facing sand 19b through the cope flask 5 to the compartment 20 having the same clear widths dimensions as the cope flask 5. This compartment 20 is formed by the lift table 46 and the frame 21 and by an opening of the same size in turntable 1. The compartment 20 is closed on the bottom by a fixed sheetmetal bridge 23 which reaches from station to station 1 1. Subsequently, the cope flask 5 is indexed by turntable 1 to position 11 where the compression and draw cycle takes place. The corresponsing pattern 27 (see FIG. 3) has been indexed simultaneously from position 24 by turntable 2 into a position precisely above position 11 of the turntable l. (The sequence of operations of compressing and vibrating and subsequently drawing the mould downwards, taking place now, is described later in more detail.) The cope flask 5 is again set down on turntable l in position 11. Thereafter, turntable l indexes to position 12 where the cope flask 5 is transferred by means of clamping fixtures 28 (FIG. 2) of the transfer unit 29 to position 17 from position 12. The automatic milling unit 18 cuts off the sand projecting from the bottom of the mould (position 17). (During the transfer of the cope flask 5 onto position 17, the drag flask positioned there prior to this movement, is transferred with the same transfer unit 29 but with different clamping fixtures 30 simultaneously to station 13 of the turntable 3 see FIG. 2.)

After another index of the turntable 1 by 90 during the following cycle, the cope flask 5 is transferred by means of the clamping fixtures 30 of the transfer unit 29 into position 13 of turntable 3. The flasks are indexed by turntable 3 to the operating stations for the cutting of-the pouring basin, the drilling of the sprue hole and the piercing of the vent holes. The operations are separated into position 13 for the automatic cutting of the pouring basin (pouring system for the metal receiving) by means of the milling unit 13a, into position 14 for the automatic drilling of one or more sprue holes by means of the sprue drill unit 31 and into position for the automatic piercing from top of the air vents by means of the venting fixture 32. The cope flask is set down into position 34 of the core setting line 35 from position 16 of the turntable 3 with a transfer unit 33 (not shown). Cope moulds and drag moulds follow each other during the production run on the core setting line 35 with the opened pattern area facing upwards in the proper position for core setting and inspection. The

empty flasks

5 and 6 which move individ-' ually on conveyor 4 are each located on a pallet 5a which moves after take off of the flask empty to position 7 and receives the drag flask 6 at position 34.

v The cope flasks 5 from position .34 are also transferred to a freed pallet 5a in the core setting line 35. Those pallets 5a have been previously returned on a pallet return line (not shown) arranged beneath the core setting line 351

Thee flasks

5, 6 are indexed with turntable 2 into the compression station 11 of turntable 1. Cope

patterns

25, 27 and drag patterns 24a, 26a (not shown) residing respectively in

positions

24 and 26 on FIG. 1 are normally moved alternately to compression station 11 of turntable 1. When larger series are required from one pattern pair, then only these patterns are indexed back and forth into the compression station 11. The removal of those patterns that are no longer required takes place at position 36, corresponding to the storage area for used patterns and after a turn, a new pattern half is introduced into the system at position 37, corresponding to the storage area for new patterns. A pattern exchange without interruption of the cycle is possible. After the pattern exchange at a later point of time, the sprue drilling unit 31, 31a of the sprue drilling circulation unit 38 must be readjusted. The venting combination 32 and 32a of the venting circulation unit 39 is exchanged two cycles later if required, after a prior pattern exchange. One operator, therefore, can take care of all work functions successively in connection with a pattern exchange without disruption of production.

FIG. 2 shows the sandfill station 19, which is station 10 shown in FIG. 1. The sandhopper 19c is separated by two

blade locks

40 and 41 into two

compartments

42 and 43, one on top of the other. The required facing sand is in the top compartment 42. The required amount of backing sand has been charged into the lower compartment 43 by a sand delivery system (not shown). After the index of, for example, the cope flask 5 into position 10 of the turntable l, the blade lock 41 opens automatically simultaneously operating an aerating unit 44 to achieve an even distribution of backing sand in the compartment 20 below. Thereafter, the blade lock 40 is opened and the facing sand 19b falls through the already opened blade lock 41 and through the aerating unit 44 evenly distributed into the compartment 20. The required amount of moulding sand for the mould making has so been charged at station 10 without any loss of sand. The precharging of the sandhopper 19c with backing sand into the compartment 43 takes place after closing of the blade lock 41 and the precharging of facing sand into the compartment 42 after closing of the blade lock 40.

An important unit of the multiple station direct moulding automat is shown in FIG. 3. In this station, the compacting and drawing down of the mould takes place. In this position 11 of turntable 1, beginning at the bottom, the press cylinder 45 with the lift table 46 above, are arranged. On top of the lift table 46 area number of equalizing cylinders 47 with equalizing pistons 48 arranged so that the complete mould flask area is covered by the equalizing pistons 48. The upper surfaces of the equalizing pistons 48 are in their lower start-up position in horizontal alignment with the upper surface of fixed sheetmetal bridge 23 of the sandfill station 10, or respectively in one line with lower surface of the opening 22 of turntable 1 and therefore closing the bottom of the opening.

Each of the equalizing cylinders 47 is in liquid communication with a line 47a which in turn is provided with an adjustable pressure relief valve (not shown). By adjusting these pressure relief valves to different pressures, the outer equalizing pistons can be adjusted to give a pressure on the sand which is different from the inner equalizing pistons. The lift table 46 is equipped with four lift pins 49 which correspond with the above guide pins 50 which are fastened in the vertically slidable frame 21. The frame 21 encloses the compartment 20 and can be lifted upwards from turntable 1. The cope flask 5, for example, rests on the top surface of frame 21 and is properly positioned with locating pins 51. Above the cope flask is the frame 53 movable in guide pins 54 with inner dimensions to enclose precisely the pattern 27 and only far enough above the cope flask 5 to avoid its locating pins 52 during the rotation of either the cope flask 5 or the frame 53. The pattern 27 is fixed to turntable 27a with a spacer 55 and is supported against the compressive force by a bearing 56 which is connected by the machine frames at the side with the lower foundation frame 57. A vibrating unit 58 is mounted within the bearing 56.

The loose back up sand 19a and the loose facing sand 1912 as shown in FIG. 4, Position a, has been indexed over the fixed sheetmetal bridge 23 from the sandfill station into the operating position. The top surfaces of the equalizing pistons 48 support the sand and close the lower opening 22 of the turntable 1. First, the equalizing cylinders 47 receive pressure and the equalizing pistons 48 move the sand up. As soon as the evenly upward moving equalizing pistons 48 have reached the parting line 59, which is identical with the lower surface of frame 21, the press cylinder 45 also receives pressure. In addition, the lift table 46 now moves up together with the equalizing cylinders 47 and the four lift pins 49. The lift pins 49 position themselves in the guide pins 50 and lift the frame 21 as well as the cope flask 5 from the turntable 1 whereby the cope flask 5 in Position b comes into contact with frame 53 and so closes completely tightly the entire compartment in which the sand is moving up. The frame 53 slides simultaneously on guide pins 54 upwards past the pattern parting line 60 according to the lifting speed of press cylinder 15. The vibrating unit 58 is switched on now. Since it is not possible for the sand to escape sideways, a counteracting pressure is applied to the equalizing pistons 48 according to the different elevations of the pattern 27 and the equalizing pistons 48 adjust themselves to different stroke lengths (see Position c). The desired compressive pressure is controlled by a relief valve (not shown) to a desired pressure per square inch moulding area (above 100 psi high pressure moulding) and after exceeding this pressure, the cope flask 5 moves past the sand package into its final upper position because of the greater force of the press cylinder 45. The pattern 27 is pressed directly into the sand (direct moulding method) from the top down under simultaneous vibrations to maintain the fluidity of the sand. The final upper position of the cope flask 5, according to Position d, has been reached if the

complete frame arrangement

21, 5, 53, is pressed against the support bearing 56. The high dimensions of the upper frame 53 are selected so that the generally desired sand projection is maintained. Herewith, the compression cycle is completed. The draw cycle of the compacted mould half is initiated by a slow and thereafter (Position 2) fast lowering of the lift table 46 by switching off the vibrator 58 during the last part of the slow draw. The equalizing pistons 48 are moved down faster in relation to the lift table 46 to relieve the pressure at the mould surface. This situation is shown in Position f.

Position 3 shows the cope flask 5 resting on turntable 1, ready for further transport to position 12.

FIG. 5 demonstrates how it is possible to double the capacity of the previously explained system by adding a second turntable group. In this complex, one turntable group produces only cope flask moulds and the other turntable group produces only drag flask moulds. The return conveyor 61 for empty flasks transports pairs of cope flasks 89 and drag flasks 90 upon a pallet 91 into position 62. A transfer unit 63 (not shown) takes the cope flask 89 from position 62 and transfers it into position 64 of turntable 65 for the making of the cope flask mould. The cope flask 89 is indexed by turntable 65 into the sandfill station 66 and subsequently into compression station 67. Prior to this, a pattern has been indexed into station 67 by turntable 68. This pattern circulation unit 68 contains three different patterns, for example. It is however, possible to arrange for any other number of patterns according to the existing production schedule requirements. At similar sized production series, the patterns 69 and 70 pass the compression station 67 one after the other. At the production requirements of a larger series from one and the same casting however it is possible to contain a pattern in the compression station 67 for a longer period of time once it has been indexed into this station. This is controlled by a program selection at the automatic control system (not shown) for this unit. After the cope flask 89 completes the compression and draw cycle, it is indexed by turntable 65 into position 71 from where the cope flask 89 is transported by a transfer unit 72 (not shown) into position 73 for automatic cut-off of the mould back in this position. During the following operation cycle, the transfer unit 72 moves the cope flask 89 with the other set of clamping fixtures into position 74 of turntable 75. The pouring basin is cut into the mould at position 74. The turntable 75 indexes further by 90 and indexes the cope flask 89 into station 76 for automatic drilling of the sprue holes. The fixture for the drilling of one or more sprue holes is a part of drilling circulation system 77. The number of

different drilling systems

78 and 79 correspond with the number of patterns in the pattern circulation unit 68 and, for example, is shown here with three stations. The finished drilled mould in cope flask 89 is further indexed by turntable 75 into station 80. The vent holes are pushed from the top into the mould by the venting circulation unit at station 80. The venting circulation unit consists of turntable 81, with, for example, two venting

pierce fixtures

82 and 83. The number of fixtures in this arrangement corresponds with the number of fixtures in the pattern circulation unit 68. Another index cycle of turntable 75 moves the mould in cope flask 89 into position 84. The transfer unit 85 as shown in FIG. 6 takes this cope flask and transports it into position 86 which is above the conveyor 85a for empty drag flasks.

At further cycles of operations the cope flask mould is moved with transfer units 85 and 86a to position 87. Here the cope flask 89 is set down onto a pallet 88 which has been returned to this station by a pallet return conveyor 92 (not shown) which is arranged beneath the cope flask transport conveyor 92a. Those moulds can be inspected. Cores can be set on this cope mould transport conveyor 92a and the transport moves on to a mould closing fixture (not shown). After removing the cope flask 89 in position 62, only the empty drag flask remains in this position on pallet 91. Both are further transported underneath station 86 to position 93. A transfer station 94 (not shown) transports the empty flask 90 into station 95 of turntable 96. The drag flask moulds are produced in this station. The sequence of operations is the same as described for the machine producing the cope flask moulds. This turntable 96 is identical in its dimensions with the

turntables

65 and 75. The operations follow with sand filling in station 97, mould compressing and mould draw in station 98 and index into station 102. Prior to this, the proper pattern has been indexed into station 98 by the pattern circulation unit 99 which is identical in arrangement with the pattern circulation unit 68 and contains the pattern plates 100 and 101. A transfer unit 103 (not shown) moves the drag flask 90 into station 104 where the lower mould back is cut off. The same transfer unit 103 subsequently moves the drag flask 90 into station 105 of the turntable 106 which is identical with the turntable 75. No further operations are performed in this turntable. Cores can be set in

stations

107 and 108. These stations are especially suitable for the automatic core setting, for example, of cylinder block cores also with circulating core setting fixtures (iron arms), similar to

turntables

68, 81 and 99. The turntable 96 is used for the transport of the drag flask 90 over

stations

107, 108 to 109. The drag flask 90 is from here transferred by transfer unit 100 (not shown) into station 111 on the pallet 91 which arrived in the meantime. From here, the drag flask mould moves into the core setting conveyor 112 where the cores are set.

FIG. 7, for example, shows a system with only one turntable 113 for the flask circulation and one turntable 114 for the pattern circulation. For low capacity requirements, cope and drag flask moulds are produced here successively. A separating unit (not shown) has already separated the cope flasks 116 from the drag flasks 117 and replaced the cope flask behind the drag flask upon a pallet 118 in the return conveyor for empty flasks. The pallets for the cope flasks are returned later beneath the core setting conveyor 119.

An empty drag flask 117 is removed from the pallet 118 in station 121 and transferred with a transfer unit 120 onto the free station 122 of turntable 113. The turntable 113 indexes this flask into the sandfill station 123 whereby another moulded drag flask 117 is indexed into station 122 which is further transferred back by transfer unit 120 onto the free pallet in station 121. Station 122 of the turntable is therefore empty now and during the following cyle is indexed without an empty flask into sandfill station 123 which does not operate during this coming cycle of operations. At the same time the turntable 114 indexes a new pattern into the compression station ahead. Also the previously mentioned drag flask 117 has been indexed simultaneously into the compression station 124, compressed and the pattern drawn according to the previously explained method. An empty cope flask 116 is transferred at the same time with th transfer unit 120 from station 121 to the free station 122 of the turntable 113. Therefore, the following situation is established: station 121 on the pallet conveyor 119 is emtpy, station 122 is occupied with an empty cope flask, station 123 for the sand charging is empty, a finished drag flask mould is located in compression station 124, the turntable 114 for the pattern circulation indexes only every other cycle of the turntable 113 for the flask circulation since every other station in the area of the compression station 124 is without a flask.

The mould is indexed from station 124 to 126 and further transported into station 128 with a transfer unit 127 (not shown) where the mould back is cut smooth. After a further index cycle of turntable 113 and of the pallet conveyor 119, this drag flask mould 11-7 is returned to the emptied station 126 by the transfer unit 127.

During another index cycle of turntable 113, the cope flask mould 116 is moved to station 126 and further to station 128 for the smooth cutting of the mould back as well as the piercing of the vent holes with the venting fixture and subsequent return transfer to station 126 for the cutting of the pouring basin from underneath. The last operation on the cope flask mould is performed in station 122 by the drilling of the sprue hole.

The patterns can be exchanged without stopping the machining cycles in

stations

129 and 130 of the turntable 114 for the pattern circulation.

As many moulds as desired can be produced from only one pattern by turning the turntable 114 for the pattern circulation back and forth. Therefore, also this system permits the adjustment of the pattern scheduling to larger series of production.

The capacity of this system is only one quarter of the previously described system equipped for separate production of cope and drag flask moulds. Since this transport system moves only every other cycle, one pattern half of the four circulation pattern halves is moved into the compression station.

What is claimed is:

1. An apparatus for producing foundry moulds comprising:

A. a machine frame,

B. a flask turntable vertically journaled on the machine frame,

C. a pattern turntable vertically journaled on the machine frame,

D. a flask resting on the flask turntable,

E. a pattern depending from the pattern turntable,

F. means for placing sand ina compartment comprising the flask,

G. means for rotating the flask turntable and the pattern turntable to position the pattern above the flask,

H. equalizing pistons means for pressing the pattern into the sand while confining the sand to the compartment;

I. a drilling turntable vertically journaled on the machine frame adapted to drill holes up from the bottom in the mould while the mould is in the flask,

J. means for transferring the mould in the flask from the pattern turntable to the drilling turntable.

2. The apparatus of claim 1, wherein the compartment comprises:

a. an opening in the pattern turntable,

b. a first vertically slidable frame resting on the turntable,

0. the flask resting on the slidable frame, the flask having a cavity,

d. a second vertically slidable frame surrounding the pattern, the second frame having a cavity, wherein the inner transverse dimensions of the opening and the cavities of the frame are all equal.

3. The apparatus of claim 1, wherein the outer equalizing pistons can be adjusted to different compressive pressures from the inner equalizing pistons.

4. The apparatus of claim 1, further comprising a sand hopper positioned above the flask turntable and adapted to deposit a premeasured amount of sand into the flask,

wherein the sand hopper is divided into two vertically spaced compartments separated by a bladelock, the bottom of the lower compartment having a bladelock, whereby the flask can be filled with coarse sand located in the lower compartment and finer facing sand located in the upper compartment.

5. An apparautus of claim 1 for the production of foundry moulds comprising:

A. said flask support table having a major opening therein flanked by two minor openings adapted to receive guide pins,

B. said pattern means including a first vertically slidable frame having an inner cavity of transverse dimensions exactly corresponding to the major opening in the flask support table, the walls of the vertically slidable frame being positioned over the minor openings in the flask support table,

C. said flask having an inner cavity, the inside transverse dimensions of which exactly correspond to the inside transverse dimensions of the inner cavity of the vertically slidable frame and of the major opening in the flask support table,

D. said pattern turntable vertically journaled on the frame on an axis parallel to the axis of rotation of the flask support table,

E. a pair of guide pins depending from the pattern table,

a second vertically slidable frame slidably mounted on the guide pins, the second frame having a central cavity, the transverse dimensions of which are identical to the transverse dimensions of the flask, the first slidable frame, and the major opening in the flask support table,

G. a pattern attached to, and depending from, the

pattern turntable, the pattern lying within the cavity of the second slidable frame,

H. an upwardly opening press cylinder attached to the machine frame,

I. a piston slidably mounted in said press cylinder,

J. a lift table attached to the press piston,

K. a plurality of vertically extending equalizing cylinders attached to said lift table,

L. a number of equalizing pistons slidably mounted on each of said equalizing cylinders, the upper surfaces of said equalizing pistons defining a surface closing the bottom of the compartment defined by the major opening in the flask support turntable, the first slidable frame, and the flask, each of said equalizing cylinders being in liquid communication with a line having an adjustable relief valve therein,

M. a pair of lift pins attached to said lift table being vertically mounted to slide through the minor holes in the pattern turntable and contact the first slidable frame in order to move it upward, wherein:

a. the major opening in the pattern turntable, the first slidable frame, the second slidable frame, and the flask define a sand-retaining compartment,

b. application of hydraulic pressure on the press cylinder raises the lift table causing the equalizing cylinders to raise the sand compressing it around the pattern in the compartment.

6. An apparatus for continuous manufacture of casting moulds in mould boxes prefilled with sand comprising:

a plurality of work stations;

a first turntable provided with means to carry said mould boxes and means to index at a predetermined cycle said mould boxes from work station to work station;

a squeeze unit and a compressing station;

a plurality of pattern plates with patterns facing downwards;

a second turntable;

means to mount said plurality of pattern plates on said second turntable;

means to lift said mould boxes prefilled with sand against one of said patterns at a time; and

means to lower said boxes;

said second turntable mounted with its orbit to cross the orbit of said first turntable at the compression station;

said first turntable comprising a mould box unloading station further comprising:

a third turntable to receive and transport said mould boxes;

an intermediate station with a cut-off unit;

said third turntable spaced from said mould box station by said intermediate station;

a sprue drilling fixture and a venting fixture mounted with their orbital path to intercept the paths of said plurality of work stations.

7. An apparatus for continuous manufacture of casting moulds as claimed in claim 6,

said first turntable further comprising means to index within one rotation successively into four working positions;

said plurality of work stations further comprising:

a mould box loading station;

a sandfill station;

said second turntable provided with a plurality of work stations and means to index at the said cycle of said first turntable differing to size and directions.

Claims

1. An apparatus for producing foundry moulds comprising: A. a machine frame, B. a flask turntable vertically journaled on the machine frame, C. a pattern turntable vertically journaled on the machine frame, D. a flask resting on the flask turntable, E. a pattern depending from the pattern turntable, F. means for placing sand in a compartment comprising the flask, G. means for rotating the flask turntable and the pattern turntable to position the pattern above the flask, H. equalizing pistons means for pressing the pattern into the sand while confining the sand to the compartment; I. a drilling turntable vertically journaled on the machine frame adapted to drill holes up from the bottom in the mould while the mould is in the flask, J. means for transferring the mould in the flask from the pattern turntable to the drilling turntable.

2. The apparatus of claim 1, wherein the compartment comprises: a. an opening in the pattern turntable, b. a first vertically slidable frame resting on the turntable, c. the flask resting on the slidable frame, the flask having a cavity, d. a second vertically slidable frame surrounding the pattern, the second frame having a cavity, wherein the inner transverse dimensions of the opening and the cavities of the frame are all equal.

4. The apparatus of claim 1, further comprising a sand hopper positioned above the flask turntable and adapted to deposit a premeasured amount of sand into the flask, wherein the sand hopper is divided into two vertically spaced compartments separated by a bladelock, the bottom of the lower compartment having a bladelock, whereby the flask can be filled with coarse sand located in the lower compartment and finer facing sand located in the upper compartment.

5. An apparautus of claim 1 for the production of foundry moulds comprising: A. said flask support table having a major opening therein flanked by two minor openings adapted to receive guide pins, B. said pattern means including a first vertically slidable frame having an inner cavity of transverse dimensions exactly corresponding to the major opening in the flask support table, the walls of the vertically slidable frame being positioned over the minor openings in the flask support table, C. said flask having an inner cavity, the inside transverse dimensions of which exactly correspond to the inside transverse dimensions of the inner cavity of the vertically slidable frame and of the major opening in the flask support table, D. said pattern turntable vertically journaled on the frame on an axis parallel to the axis of rotation of the flask support table, E. a pair of guide pins depending from the pattern table, F. a second vertically slidable frame slidably mounted on the guide pins, the second frame having a central cavity, the transverse dimensions of which are identical to the transverse dimensions of the flask, the first slidable frame, and the major opening in the flask support table, G. a pattern attached to, and depending from, the pattern turntable, the pattern lying within the cavity of the second slidable frame, H. an upwardly opening press cylinder attached to the machine frame, I. a piston slidably mounted in said press cylinder, J. a lift table attached to the press piston, K. a plurality of vertically extending equalizing cylinders attached to said lift table, L. a number of equalizing pistons slidably mounted on each of said equalizing cylinders, the upper surfaces of said equalizing pistons defining a surface closing the bottom of the compartment defined by the major opening in the flask support turntable, the first slidable frame, and the flask, each of said equalizing cylinders being in liquid communication with a line having an adjustable relief valve therein, M. a pair of lift pins attached to said lift table being vertically mounted to slide through the minor holes in the pattern turntable and contact the first slidable frame in order to move it upward, wherein: a. the major opening in the pattern turntable, the first slidable frame, the second slidable frame, and the flask define a sand-retaining compartment, b. application of hydraulic pressure on the press cylinder raises the lift table causing the equalizing cylinders to raise the sand compressing it around the pattern in the compartment.

6. An apparatus for continuous manufacture of casting moulds in mould boxes prefilled with sand comprising: a plurality of work stations; a first turntable provided with means to carry said mould boxes and means to index at a predetermined cycle said mould boxes from work station to work station; a squeeze unit and a compressing station; a plurality of pattern plates with patterns facing downwards; a second turntable; means to mount said plurality of pattern plates on said second turntable; means to lift said mould boxes prefilled with sand against one of said patterns at a time; and means to lower said boxes; said second turntable mounted with its orbit to cross the orbit of said first turntable at the comprEssion station; said first turntable comprising a mould box unloading station further comprising: a third turntable to receive and transport said mould boxes; an intermediate station with a cut-off unit; said third turntable spaced from said mould box station by said intermediate station; a sprue drilling fixture and a venting fixture mounted with their orbital path to intercept the paths of said plurality of work stations.

7. An apparatus for continuous manufacture of casting moulds as claimed in claim 6, said first turntable further comprising means to index within one rotation successively into four working positions; said plurality of work stations further comprising: a mould box loading station; a sandfill station; said second turntable provided with a plurality of work stations and means to index at the said cycle of said first turntable differing to size and directions.