Patent Publication Number: US-3878881-A

Title: Method for producing and assembling cope and drag mold parts

Description:
United States Patent 1191 Lund et a1.  
 [451 Apr. 22, 1975 METHOD FOR PRODUCING AND ASSEMBLING COPE AND DRAG MOLD PARTS [75] lnventors: Robert S. Lund, Elmhurst; Vernon .1. Koss, Niles. both of I11.  
 [73] Assignee: Pettibone Corporation, Chicago, 111.  
 [22] Filed: Oct. 23, 1973 [21] Appl. No.: 408,483  
  Related U.S. Application Data [62] Division of Ser. No. 233.438. March 10, 1972, Pat.  
 [52] U.S. C1. 164/37; 164/137; 164/200; 164/243 [51] Int. Cl. B22c 11/04; 1322c 15/24 [58] Field of Search 164/37, 40, 137, 200, 243  
 [56] References Cited UNITED STATES PATENTS 3.181.207 5/1965 Schaible et a1. 164/195 X 3.229.336 1/1966 Hunter ct a1 164/195 3.508.598 4/1970 York 164/137 X 3.556.196 1/1971 Buhlcr 164/38 3.589.431 6/1971 Fellows 164/37 X 3.630.268 12/1971 Hatch 164/226 X 3.760.866 9/1973 Larkin 164/200 Primary E.\&#39;aminerR. Spencer Annear Attorney, Agent, or FirmNorman H. Gerlach [57] ABSTRACT A particular method of producing and assembling cope and drag mold parts, such method being designed to be carried out in a foundry machine embodying a rotary turntable which supports four pairs of flask sections and is repeatedly indexed to move the pairs repeatedly and successively in a circular path through four stations, namely, (1) a working station where the flask sections are variously and automatically handled and in cooperation with a patterncarrying match plate are filled and compacted with foundry sand so as to produce the two mold parts, (2) a core-setting station where, if required or desired, a core may be applied to one of the formed mold parts, (3) a stripping station wherein the flask sections are again variously handled to strip the sections from the mold parts and the latter are assembled and then deposited on a bottom board which is ejected from the machine, and (4) an idle or dwell station where an empty pair of flask sections awaits handling of a preceding pair of flask sections at the working station before being returned to such station for refilling thereof at the commencement of the next machine cycle.  
 3 Claims, 36 Drawing Figures ffi22i975 8.878.881  
 am 3 0f 8 FIG. 5  
 HIENTEE FIG. 8  
 WENTEB APR 2 21975 saamsq gs 370 37 s sogn I82 an L METHOD FOR PRODUCING AND ASSEMBLING COPE AND DRAG MOLD PARTS This application is a division of our copending US. patent application Ser. No. 233,438, filed on Mar. 10. 1972, now US. Pat. No. 3,828,840 and entitled MATCH PLATE MOLDING MACHINE WITH RO- TARY FLASK TRANSFER FOR PRODUCING AND ASSEMBLING COPE AND DRAG MOLD PARTS.&#34;  
  The present invention relates generally to a method of producing sand molds for foundry use and has par ticular reference to a method which may effectively be carried out by means of a foundry machine such as that which is shown and described in said copending US. patent application Ser. No. 233,438.  
  Heretofore, in connection with a foundry machine which resorts to the simultaneous blowing of the cope and drag parts of a composite sand mold by the utilization of a dual-sided, horizontally positioned, pattern carrying match plate, it has invariably been the practice to perform all machine functions at a single working station where various flask and match plate movements take place with vertical in-line motion under the control of a ram, such movements including, first, bringing a pair of cope and drag flask sections into clamping engagement with the match plate in order to define above and below the match plate cope and drag sandreceiving cavities which are then filled with sand by a simultaneous combined blow and compacting operation, second, performing a squeeze operation by means of which the sand in both cavities is simultaneously and additionally compressed or compacted about the match plate so as to produce the cope and drag parts of the composite mold, third, separating the flask sections with the mold parts therein in order to permit withdrawal of the match plate to an out-of-the-way po&#39; sition. fourth, closing the two flask secitons on each other in order to assemble the mold parts and produce the completed composite mold, fifth, performing a push-out or stripping operation by means of which the assembled composite mold is pushed bodily from the confining flask sections, and last, widely separating the flask sections and then pushing or ejecting the completed and assembled mold bodily from the working station and onto a bottom board. One molding machine of this general type is illustrated and described in US. Pat. No. 3,229,336; granted on Jan. 18, 1966 and entitled &#34;MATCH PLATE MOLDING MACHINE FOR THE SIMULTANEOUS PRODUCTION OF COPE AND DRAG MOLD SECTIONS. Another example of such a molding machine is to be found in US. Pat. No. 3,648,759, granted on Mar. 14, I972 and entitled MACHINE FOR MAKING SAND MOLDS.&#34;  
  Method of the present invention is designed as an improvement over the method which is carried out by such single-station match plate molding machines in that it contemplates the provision of a method wherein the aforementioned stripping operation is completely divorced from the working station and performed at a separate stripping station, while an additional station, namely, a core-setting station, is provided to the end that, if required, the step of placing a core between the two mold parts preparatory to performance of the stripping and ejecting station may be attended to. The provision of these two additional steps at two separate stations, obviously necessitates transfer of the flask sections from the working station where the complemental cope and drag mold parts are initially created within the flask sections, to the core&#39;setting station and from thence to the stripping station. Thus, in order that the flask-handling instrumentalities at the working station shall not remain idle while awaiting performance of the core-setting and stripping operations successively at the two other stations, the present method makes provision for the use of plural pairs of cope and drag sand mold flask sections, together with transfer means whereby as soon as given pair of flask sections has been operated upon the working station, the step of conducting such sections with the mold parts therein to the core-setting station is performed while at the same time a second pair of empty flask sections is moved into the working station for handling thereat according to the present method while the coresetting steps are being carried out at the core-setting station. Similarly, according to the present foundry method, when the second pair of flask sections has been operated upon at the working station and core-setting operations have been completed at the core-setting station, steps are performed whereby both pairs of flask sections are con ducted from such stations, the first pair of flask sections moving to the stripping and ejecting with the core in place and the second pair being conducted to the coresetting station while a third pair of flask sections is brought into the working station.  
  After the three pairs of flask sections have been operated upon at the working station, the core-setting station and the stripping and mold-ejecting station by the performance of the various necessary steps simultaneously at such stations, all three pairs of flask sections are then moved from such stations, the first pair (now empty of contents) being conducted to a fourth idle or dwell station, the second pair being conducted to the stripping and mold-ejecting station, and the third pair being conducted from the working station to the coresetting station, while a fourth pair of flask sections is moved into the working area from the idle or dwell station. The various steps of moving the four pairs of flasks and of operating or handling them at the sequentially arranged stations are all performed within the limited area which is offered by the machine which is employed in carrying out the method and the flask&#39;sections never leave the confines of such machine.  
  The object of the invention is the provision of the particular aforementioned method.  
  In the accompanying eight sheets of drawings forming apart of this specification, a foundry machine which is capable of carrying out the method of the present invention is disclosed. In these drawings:  
  FIG. I is a top plan view of a match plate molding machine which is capable of performing the method steps of the present invention, the machine being shown as devoid of flasks but with flask positions being illustrated in dotted lines;  
  FIG. 2 is a side elevational view of the machine of FIG. I with a similar dotted line flask disclosure;  
  FIG. 3 is an end elevational view of the machine of FIG. I with a similar dotted line flask disclosure;  
  FIG. 4 is a fragmentary side elevational view, some what schematic in its representation, of the Geneva drive mechanism which is employed in connection with the molding machine of FIG. 1;  
  FIG. 5 is an end view of oneof a series of cope flask sections which are employed in. the performance of the present method,  
  FIG. 6 is an end view of the match plate which is employed in connection with the method at the working station;  
 FIG. 7 is an end view of one of a series of drag flask sections which are employed in connection with the method;  
  FIG. 8 is a side elevational view of an assembled cope flask section and drag flask seciton, such sections being previously illustrated in FIGS. and 7, respectively:  
  FIG. 9 is a top plan view of the structure which is shown in FIG. 8;  
  FIG. 9a is an horizontal sectional view taken on the line 9a 9a of FIG. 2 and representing, largely, a plan view of the upper turntable spider. the lower turntable spider and the underlying portions of the machine being omitted in the interests of clarity;  
  FIG. 9b is a side elevational view of the structure of FIG. 9a;  
  FIG. 90 is a sectional view taken on the line 9c9c of FIG. 2 and representing, largely, a plan view of the lower turntable spider with the underlying portions of the machine omitted;  
  FIG. 9d is a side elevational view of the structure of FIG. 9(&#39;;  
  FIG. 10 is an enlarged detail sectional view taken substantially centrally and longitudinally through one of the numerous vents or filter screen units which are employed in connection with cope and drag flask sections of the machine;  
  FIG. 11 is a perspective view of the vent or filter screen unit of FIG. 10;  
  FIG. 12 is a sectional view, largely schematic in its representation, taken vertically and centrally through the working area or station of the machine and illustrating the associated ram assembly. the flask sections and the match plate in their normal positions of the commencement of a machine cycle;  
  FIG. 13 is a schematic sectional view similar to FIG. 12 but illustrating a preliminary movement ofa certain part of the ram assembly which takes place at the commencement of the machine cycle and invloves upward shifting of the lift sleeve of the assembly together with the associated cope upset while the lift plunger of the ram assembly remains stationary;  
  FIG. 14 is a schematic secitonal view similar to FIG. 13 but illustrating an upward lift plunger movement which takes place in order to lift the drag flask section against the match plate;  
  FIG. 15 is a schematic sectional view similar to FIG. 14 but illustrating the drag and cope flask sections in position against the match plate due to a further upward movement of the lift plunger of the ram assembly;  
  FIG. 16 is a schematic sectional view similar to FIG. 15 but illustrating the drag flask section and the cope flask section. both in their fully clamped positions and immediately prior to the blow operation whereby moldforming sand is introduced and compacted into both flask sections;  
  FIG. 17 is a schematic sectional view similar to FIG. 16 but illustrating the blow operation whereby the cope and drag flask sections are filled with sand and simultaneously compacted by blowing;  
  FIG. 18 is a schematic sectional view similar to FIG. 17 but illustrating the positions of the drag and cope flask sections and the parts of the ram assembly during the sand-squeezing operation which takes place between upper and lower squeeze plates.  
  FIG. 19 is a schematic sectional view similar to FIG. 18 but illustrating the downward movement of the lift plunger of the ram assembly which takes place immediately after the sand-squeezing operation;  
  FIG. 20 is a schematic sectional view similar to FIG. 19 but illustrating a further downward movement of the lift plunger of the ram assembly which takes place in order to restore the cope flask section to its normal supported position on the turntable;  
  FIG. 21 is a schematic sectional view similar to FIG. 20 but illustrating a still further downward movement of the lift plunger of the ram assembly which takes place in order to restore both of the sand-filled and compacted flask sections. and also the match plate, to there respective normal supported positions;  
  FIG. 22 is a schematic sectional view similar to FIG. 21 but illustrating the sand-filled and compacted cope and drag flask sections indexed away from and out of the working area or station of the machine, and also showing or illustrating new empty cope and drag flask sections being indexed into the working station in order to replace the withdrawn flask sections;  
  FIG. 23 is a schematic sectional view taken vertically through the core-applying station of the machine. that is, the station to which the sand-filled and compacted cope and drag flask sections that are removed from the working area of the machine are indexed, and showing a core in position on the lower or drag mold part;  
  FIG. 24 is a side elevational view. largely schematic in its representation, illustrating the mold-stripping mechanism at the stripping station in the normal position which is assumes at the time the sand-filled and compacted cope and drag flask sections are indexed into respective normal suported positions at the stripping station;  
  FIG. 25 is a schematic side elevational&#39;view similar to FIG. 24 but illustrating the preliminary upward movement of a certain mold-closing lift bracket into effective lifting engagement with the filled drag flask I to FIG. 25 but illustrating a further upward shifting movement of the lift bracket so as to bring the filled drag flask section into initial effective lifting engagement with the filled cope flask section;  
  FIG. 27 is a schematic side elevational view similar to FIG. 26 but illustrating a still further upward movement ofthe lift bracket so as to bring the filled drag and cope flask sections into operative relationship with respect to a stripping platen which is employed in connection with the machine;  
  FIG. 28 is a schematic side elevational view similar to FIG. 27 but illustrating the actual stripping operation wherein the cope and drag flask sections are stripped bodily and in unison from the assembled complemental moldparts;  
  FIG. 29 is a schematic side elevational view similar to FIG. 28 but illustrating a downward movement of the lift bracket preparatory to restoring the cope and drag flask sections to their normal turntable-supported positions within the stripping station;  
  FIG. is a schematic side elevational view similar to FIG. 29 but illustrating a further downward movement of the lift bracket which restores the cope flask section to its normal turntable-supported position at or within the mold-stripping station of the machine;  
  FIG. 31 is a schematic side elevational view similar to FIG. 29 but illustrating a still further downward movement of the lift bracket which restores the drag flask section to its normal supported position within the stripping station of the machine and deposits the assembled composite mold on a bottom board; and  
  FIG. 32 is a side elevational view of the structure of FIG. 31.  
 BRIEF DESCRIPTION OF THE MACHINE Referring now to the drawings in detail and in particular to FIGS. 1 and 2, one exemplary form of an automatic molding or mold-forming machine for carrying out the present method is designated in its entirety by the reference numeral 10. This machine is shown in the drawings as being positioned upon the floor 12 or other supporting surface of a foundry or similar establishment.  
  Briefly, the mold-forming machine involves in its general organization a fixed machine framework 14 which establishes a series of four quadrilaterally disposed areas or stations in the form of a main working area or station WS, a core-setting station CS, a moldstripping station SS. and an idle or dwell station DS. The four stations are disposed 90apart circumferentially about the central vertical axis of an intermittently indexable or moveable turntable 16 having facilities associated therewith for loosely supporting four pairs of flask sections. each pair including an upper or cope flask section 18 and a lower or drag flask section 20. Such flask sections are illustrated in dotted lines in FIGS. 1 and 3, inclusive, in the interests of clarity. The turntable 16 is indexable in 90increments of rotary motion and, upon each indexing operation thereof, the pairs of flasks at each station are transferred bodily to the next adjacent station in the direction of rotation of the turntable, such direction being clockwise as viewed in FIG. 1.  
  During each turntable indexing operation, a pair of empty cope and drag flask sections 18 and 20 is transferred from the idle or swell station DS to the main working station WS where the sections are operated upon by automatic flaskhandling mechanism in a cyclic manner to the end that they are first brought into operative enagement with a pattern-carrying match plate 22 by a clamping operation, the two flask sections are then simultaneously filled with prepared molding sand by a blow operation which compacts the sand in a preliminary manner in the mold cavities in the cope and drag flask sections. the sand in the two flask sections 18 and 20 is then further compacted about the pattern on the match plate 22 by a squeeze operation, and the flask sections are thereafter separated from the match plate 22 by a pattern draw operation in order to release them for transfer to the core-setting station CS with the compacted sand therein, while leaving the match plate 22 with its associated pattern in its normal position at the working station WS. These various automatic flaskhandling operations which are performed upon the cope and drag flask sections 18 and 20 at the working station WS are schematically illustrated in FIGS. 12 to 21, inclusive, and will be described in detail subsequently when the operation of the machine is set forth.  
  At the coresetting station CS, no automatic operations are performed on the two sand filled and compacted flask sections 18 and 20, these two sections sim ply remaining in situ on the turntable while a core is manually positioned on the compacted sand in the lower drag section 20 as shown in FIG. 23, providing. of course, that such a core is required or desired. If no core is to be used, the core-setting station CS functions in the manner of an idle or dwell station. the filled and compacted cope and drag flask sections 18 and 20 merely awaiting a succeeding or second turntableindexing operation before transfer thereof bodily to the mold-stripping station SS.  
  At the mold-stripping station SS, the separated cope and drag flask sections 18 and 20, with the compacted sand therein, are again operated upon by automatic handling apparatus in a cyclic manner whereby a bottom board 24 (see FIGS. 2 and 24 to 33, inclusive) which underlies the two mold sections is caused to move upwardly in order to effect closing of the two flask sections upon each other with consequent mating of the compacted sand mold parts therein to produce the completed composite sand mold which then engages a reaction platen 26 in a gentle manner so that further upward movement of the closed flask sections strips the flasks simultaneously from the assembled and board-supported composite sand mold. After this stripping operation, the bottom board, upon lowering thereof, carries the assembled mold downwardly to an ejecting position within the mold-stripping station SS where it may be pushed from the stripping station by a conventional ejecting mechanism (not shown). At the same time the empty cope and drag flask sections 18 and 20 are restored to their normal positions within such station, awaiting transfer to the idle or dwell station DS during the next indexing operation of the turntable 16. The automatic flask-handling functions which take place at the stripping station SS are schematically illustrated in FIGS. 24 to 32, inclusive.  
  The succesive indexing operations of the turntable which take place four times during each machine cycle are effected under the control of an hydraulicallypowered Geneva mechanism which is designated in its entirety by the reference numeral 32 in FIGS. 1, 3 and 4 and is driven by a conventional hydraulic Geneva actuator 33.  
  The flask-handling operations which take place at the main working station WS are effected under the control of an hydraulically-operable ram assembly 34 which cooperates with an upper platen assembly 35 (see FIGS. 2 and 12 to 22, inclusive). The flaskhandling operations which take place at the stripping station SS are effected under the control of an hydraulically-operable primary cylinder 36 (see FIGS. 1, 2 and 24 to 33, inclusive), as well as a set of four secondary cylinders 38 which likewise are hydraulically operated.  
  The hydraulic circuitry and associated electrical control circuitry by means of which there is effected automatic actuation of the various operating or actuating cylinders which perform flask-handling operations at the working station WS and the stripping station SS, the Geneva actuator 33 which drives the Geneva mechanism for turntable-indexing purposes, and the ejecting cylinder 40 which pushes the mold-carrying bottom boards 24 from the stripping station SS, have not been disclosed or illustrated herein since a wide variety of them is capable of performing the necessary control functions. It is deemed sufficient for purposes of discussion or disclosure herein to point out the sequence of operations which is involved during the operation of the machine, as well as particular moments in the machine cycle at which such cylinders and other hydraulic mechaisms are supplied with motive fluid.  
 THE MACHINE FRAMEWORK The machine framework 14 appears only in FIGS. 1 to 3, inclusive, and has been omitted from the remaining views in the interests of clarity except for small fragments of the framework such as various vertical supporting standards or posts. stationary flask &#34;rests or supports and platen-supporting brackets, etc. which are disposed in the working station WS and the moldstripping station SS for storage of the cope and drag flask sections 18 and 20 while they are not actually being handled by the aforementioned flask-handling mechanisms. This machine framework 14 involves in its general organization a pair of relatively massive, laterally spaced. side supports and 52 which are in the form of flat but thick castings of generally C-shape configuration, thus providing upper relatively narrow horizontal legs 54, lower relatively wide horizontal legs 56. and vertical connecting bight portions 58. Side bars 59 extend along the lower edge regions of the lower legs 56 of the side supports 50 and 52.  
  Extending forwardly from the lower legs 56 of the two side supports is a horizontal bottom frame including forwardly converging side bars 60 and a lower front end bar 62 between the front ends of the side bars. Similarly, extending forwardly from the upper legs 54 of the side supports 50 and 52 is a horizontal top frame including forwardly converging side bars 64 and a top front end bar 66 between the front ends of the lastmentioned side bars. The horizontal top frame directly overlies the horizontal bottom frame. The opposite ends of the lower front end bar 62 overhang the front ends of the forwardly converging side bars 60, and these overhanging portions have fixedly secured thereto vertical corner posts 68, the upper ends of which are fixedly secured to similarly overhanging end portions of the top front end bar 66 of the aforementioned top frame. Upper and lower intermediate transverse bars 70 and 72 extend horizontally between and are suitably secured to the two corner posts 68. The posts 68, as well as the two relatively massive side supports 50 and 52, are mounted on steel floor pads 74.  
  Mounted on the two side supports 50 and 52 in the upper regions thereof is a sand magazine 75 which is supplied with processed&#39;foundry sand from a hopper 76 through the medium of a conventional shut-off gate mechanism 78. The function of the magazine, the hopper, and the gate mechanism will be set forth subsequently when the operation of the machine 10 is described in detail.  
 THE FLASK SECTIONS As previously stated. the functioning of the present match plate molding or mold-forming machine 10 is predicated upon the provision of four sets or pairs of flask sections. each pair including the aforementioned upper or cope flask section 18 and the lower or drag flask section 20. Thesse paired sections travel in a circular path of movement under the control of the indexing movements of the turntable l6. Normally, at the commencement of any given machine cycle of operation, the flask sections of each pair are disposed at a position of rest at one of the four stations WS, CS. SS and DS and in vertically separated or spaced relationship with the cope flask section 18 overlying the drag flask section 20. At such time as the turntable 16 is actuated for indexing purposes, the thus paired flask sections at each station are transferred in an arcuate path of 90 extent to the next adjacent or following station with the four pairs of flask sections moving in a clockwise direction as viewed in FIG. 1 and as previously indicated. As will be set forth in greater detail presently, these transfer operations are made possible by the provision of an upper turntable spider 80 for supporting the four cope flask sections 18 and a lower turntable spider 82 for supporting the four drag flask sections 20. These spiders 80 and 82 consitute fixed components of the rotary&#39;turntable 16. The upper turntable spider 80 serves normally to support the four cope flask sections 18 in quadrilaterally and circumferentially spaced relationship, while the lower turntable spider 82 similarly serves normally to support the four drag flask sections 20 beneath and in vertical register with the associated cope flask sections. The specific nature of these two spiders 80 and 82 will be described subsequently when the character of the turntable 16 as a whole is described and it is deemed sufficient at present for a proper understanding of the nature of the two flask sections to state that the upper spider 80 embodies four radially extending spider arms having provision at their outer ends for supporting the associated cope flask sections 18, and the lower spider 82 embodies four similar radially extending spider arms having provision at their outer or distal ends for supporting the associated drag flask sections 20.  
 (The Upper Cope Flask Sections) Referring now to FIGS. 5 and 8 of the drawings, each of the four upper or cope flask sections 18 is in the form ofa cast metal, box-like and generally rectangular structure having opposed end walls and opposed side walls 92. These walls 90 and 92 slope upwardly and inwardly at a small angle so that each wall is of trapezoidal configuration. The upper and lower ends of the upper cope flask sections are open.  
  In the upper region of each upper cope flask section 18, each end wall 90 is provided with a horizontally extending, suspension flange 94. The latter is of appreciable width and in the medial region thereof is a bushingequipped pilot hole 96. The two pilot holes 96 of each cope flask section are designed for cooperation with mating leader pins on the upper turntable spider 80, and these, as will be made clear presently, are for the purpose of insuring proper alignment of the core flask section with the various actuating instrumentalities at the working station WS of the machine.  
  At positions near the opposite ends of the laterally extending suspension flanges 94 of each cope flask section 18 are pairs of vertical bolts 98 which extend downwardly below the level of the bottom rim of the flask section and are encompassed helical compression springs 100. The upper ends of such springs abut against the end regions of the suspension flanges 94 and the lower ends of the springs are captured by washers 102 which bear against boltheads at the lower ends of the bolts. These compression springs function in a manner that will be set forth more in detail subsequently to separate the match plate 22 from the cope flask section 18 during the aforementioned pattern draw operation at the working station WS.  
  Each cope flask section 18 is further provided with a pair of additional bushingequipped locating or pilot holes 104 and these are provided in lateral ears 105, one such ear being provided on one end wall 90 near the lower edge thereof and the other ear being similarly provided on the other end wall 90 but in offset relationship so that one of these ears appears in full lines in FIG; while the other ear appears in dotted lines. The two bushing-equipped pilot holes 104 cooperate with upstanding leader pins on the associated drag flask section 20 as will become apparent when the nature of such flask section is set forth presently.  
  The four walls 90 and 92 of each cope flask section 18 are lined with inner facings 106 (see FIGS. 5 and of elastomeric or other wear-resistant material. such walls being. therefore. of dual thickness. These walls are provided with a multiplicity of perforations 107 and each perforation has mounted therein a small cup-shaped sand screen unit 108 (see FIGS. 10 and 11), the bottom wall of which is formed with a series of narrow parallel slits 109. The latter are of such small width that, during the blow operation of the machine air may escape through the walls of the cope flask sections while the blown and compacted sand remains confined within the interior of such sections. This blow operation is performed through the open upper rim of each cope flask section 18.  
 (The Lower Drag Flask Section) Referring now to FIGS. 7 and 8 of the drawings. each lower drag flask section is in the form of a cast metal, rectangular. box-like structure having upper and lower open rims and including a pair of opposed end walls 110 and a pair of opposed side walls 112. Such end and side walls slope upwardly and inwardly to the end that each drag flask section 20 assumes the same general tapered appearance as its previously described and associated cope flask section 18. The size of the rectangular open upper rim of each drag flask section is identical to the size of the rectangular open lower rim of the associated superjacent cope flask section 18 so that these two rims will mate with each other during the flaskclamping operation which will be described hereafter. The four walls 110 and 112 of each drag flask section 20 are provided with perforations 114 which are similar to the perforations 107 in the walls and 92 of the cope flask sections 18. Each perforation 114 has associated therewith one of the screen units 108.  
  The end walls of each drag flask section 20 are provided with two lateral ears 116, there being one such each on each end wall. These ears are laterally offset from each other and have fixedly mounted thereon upstanding leader pins 118 which are adapted to register vertically within the aforementioned pilot holes 104 in the lateral ears 105 on the lower edge portions of the end walls 90 of the cope flask section 18. Additional ears 120 on one ofthe side walls 112 of each drag flask section 20 are provided with bushing equipped holes 122 (see FIG. 9) which are designed for cooperation with upstanding pilot pins on the ram 34 in a manner that will be made clear when the operation of the machine 10 is set forth.  
  Lateral flanges 124 on the end walls 110 of each drag flask section 20 are provided with bushing-equipped holes 126, the latter being designed for cooperation with depending leader pins on the match plate 22 in order properly to align the match plate and the subjacent drag flask section during the blow operation as will likewise be set forth subsequently. The holes 126 are dual-purpose holes and, in addition to being capable of mating engagement with depending leader pins on the match plate 22, they are also capable of cooperation with upstanding leader pins which are provided on the turntable and determine the normal position of the drag flask section while it is supported on the turntable.  
  As best shown in FIG. 8, one: of the end walls 110 of each drag flask section 20 is formed with an outwardly offset or displaced area 128 in which there is formed a horizontally elongated rectangular blow opening 130 through which aerated sand is blown during the blow operation when both flask sections 18 and 20 are simultaneously charged with sand. The shaded&#34; circles which appear within the confines of this blow opening 126 represent an inside view of the various sand screen units 108 which are disposed in the far side wall 112 of the illustrated drag flask section. An elongated thin bridge strip 132 defines the lower boundary of the blow opening 130. It is held in position by screws and thus obviates the disadvantage incident to a corresponding thin wall strip in the original casting from which the drag flask section is made.  
 THE MATCH PLATE AND PATTERN The match plate 22 is shown in detail in FIG. 6 of the drawings and its functional relationship in the machine is illustrated in FIGS. 12 to 22, inclusive. This match plate is sometimes referred to in the foundry industry as a pattern plate and is in the form of a flat rectangular plate to the upper and lower sides of which there are suitably secured an upper or cope pattern part and a lower or drag pattern part 142. The upper surface of the match plate 22 is designed for contact with the lower open rim of the superjacent box-like cope flask section 18 during the blow and squeeze operations of the machine at the working station WS. while the lower surface of said match plate is similarly designed for contact with the upper open rim of the subjacent boxlike drag flask section 20 during such blow and squeeze operations. When this sealing relationship is attained, the side walls 92 and end walls 90 of the superjacent cope flask section 18. in combination with the upper surface of the match plate 22, establish a cope flask cavity 144 (see FIG. 16) which, during the blow operation, becomes filled and compacted with sand as shown in FIG. 17. Additionally, the side walls 112 and end walls 110 of the subjacent drag flask section 20, in combination with the lower surface of the match plate 22, establish a drag flask cavity 146 which likewise is adapted to become filled and compacted with sand during the blow operation.  
  Four bushing&#39;equipped pilot holes 148 are provided in the four corners of the match plate 22 and are designed for cooperation with four upstanding pilot pins 150 (see FIG. 2). The latter are provided on a fixed match plate supporting bracket 152 (see also FIG. 21) which is mounted on the two side supports 50 and 52 of the machine framework and projects into the working station WS. This bracket 152 includes a pair of rearwardly and horizontally extending parallel arms 154 which are adjacent to the path of travel of the flask sections 18 and 20 as the latter move into the working station WS, and which are maintained spaced from the side supports 50 and 52 by means of inwardly extending supporting bars 156.  
  Normally, the match plate 22 rests by gravity loosely upon the two parallel arms 154 of the supporting bracket 152. It is, however, adapted to be lifted vertically from said arms by the subjacent drag flask section during flask-handling operations at the working station WS under the control of the ram 34 as will be described in detail presently.  
  The vertically extending pins 158 are fixedly connected to and depend from the match plate 22 near the side edges thereof and midway between the end edges of the match plate, and they are designed for cooperation with the aforementioned bushing-equipped holes 126 in the ears 124 on the sides of the subjacent cope flask section 20 for match plate and flask alignment purposes as previously set forth.  
  Still referring to FIG. 6, and additionally to FIG. 8, the match plate 22 is provided with a series of four holes 160 near the corners thereof, these holes being designed to accommodate and cooperate with the lower head-quipped ends of the aforementioned bolts 98 which are carried by the superjacent cope flask section 18 at such time as the lower open rim of such flask section is brought into engagement with the upper side or surface of the match plate during the flask-clamping operation at the working station WS of the machine. The diameter of these holes 160 is such that the heads of the bolts 98 may pass therethrough while the washers 102 which are loosely and slidably mounted on the bolts may not pass through such holes. Therefore. when flask-clamping operations are in progress. the springs 100 which surround the bolts 98 are placed under compression and, thereafter, after the sand-compacting or squeeze operation has been completed and clamping pressure is relieved during the push-out operation. these springs assist in separating the match plate from the bottom side of the cope mold part by overcoming any adhesive bond which may exist between the match plate and the cope mold part or the cope pattern part 140 and said cope mold part.  
 THE FLASK-SUPPORTING TURNTABLE AND ITS DRIVE MECHANISM As best shown in FIGS. 1 to 3, inclusive, the turntable 16 is supported for rotation about a vertical axis in the central region of the machine framework from a central supporting pedestal 170 from which there projects upwards a rotatable cylindrical column 172. On such column. there is fixedly secured a tubular turntable hub 174 having a cylindrical inside surface and a square outside surface. the surface presenting four vertical planar side surfaces. Secured to these four planar side surfaces of the hub 174 by way of Allen head-type bolts 175 or the like are an upper series of rectangular hub plates 176 and a lower series of rectangular hub plates 177. Such hub plates. in effect. constitute supporting brackets for a plurality of radially extending spider arms which constitute components of the aforementioned upper and lower turntable spiders 80 and 82. These turntable spiders include a series of four radially extending upper arms 180 and a similar series of four radially extending lower arms 182. The latter spider arms are in vertical register with the former arms, or stated otherwise. the lower spider arms 182 directly underlie and extend parallel to the upper spider arms 180 and are spaced downwardly therefrom as clearly shown in FIG. 2. Upper and lower bearing assemblies 184 and 186 on the machine framework 14 and the pedestal 170, respectively. receive the opposite ends of the column 172 and thus maintain the turntable as a whole in its erect vertical position. The upper bearing assembly I84 is in the form ofa ball bearing flange block and is mounted on a plate 188 on the central upper portion of the framework 14 of the machine 10.  
 (The Upper Cope Flask-Supporting Spider) Referring now to FIG. 9a of the drawings, the four radial spider arms 180 of the upper turntable spider are identical and, therefore, a description of one of them will suffice for them all. Each spider arm 180 includes one of the aforementioned rectangular hub plates I76 and from such hub plate there project radially outwards two parallel side bars 190, the inner ends of such side bars being welded to their respective or associated hub plate 176. The outer or distal ends of the two side bars 190 serve tosupport a generally T-shaped bracket 192 which consists of an intermediate leg 194, a long outer T-head 196, and a short inner T-base 198. Welded or otherwise secured to the opposite ends of the long outer T-head 196 and short inner T-bare 198 are two supporting plates 200, each plate having associated therewith an upstanding leader pin 202. Each supporting plate 200 serves normally to support one end of an associated cope flask section 18, such section thus having its opposite ends effectively resting in chordal fashion on the outer ends of a pair of adjacent radially extending upper arms 180 with the main body portion of the flask section being disposed in the general plane of the upper turntable spider 80 between adjacent upper arms 180 as shown in dotted lines at four places in FIG. 1.  
 (The Lower Drag-Supporting Spider) Referring now to FIGS. 1, 2, and 9b of the drawings, the lower turntable spider 82 is similar to the previously described upper turntable spider 80 which overlies it. the lower rectangular hub plates 177 serving to support the radially extending lower arms 182 of said lower turntable spider 82. Said lower arms 182 are similar to the upper spider arms 180 and. therefore. in order to avoid needless repetition of description, similar reference numerals with a prime suffix are applied herein to the component parts of the spider arms 182 which have corresponding counterparts as compared to the upper spider arms I80. Otherwise, it is deemed sufficient for an understanding of the nature of the lower spider arms 182 to point out the differences which exist between these lower spider arms and the upper spider arms 180.  
  The side bars 190 of the lower spider arms 182 are slightly wider in a vertical direction than the upper spider arms 180 and the supporting plates 200&#39; which are associated therewith and serve to support the drag flask sections 20 are welded along the lower edgesof the longer outer T-heads 196&#39; and the short inner T-bases 198 instead of along the upper edges thereof. This does not change the elevation of the drag flask sections 20 when they are supported by the plates 200&#39; in view of the cope flask sections 20 are positioned lower on said end walls than the lateral flanges 94 on the end walls of the cope flask sections 18.  
  Another difference between the lower spider arms 182 and the upper spider arms resides in the fact that the upstanding leader pins 202 on the supporting plates 200&#39; of the lower turntable spider 82 are not in vertical alignment with the upstanding leader pins 202 on the supporting plates 200 of the upper turntable spider 80. The distance between the leader pins 202&#39; on adjacent lower spider arms 182 is less than the distance between the leader pins 202 on adjacent upper spider arms 180. The reason for this is that the leader pins 202&#39; are designed for cooperation with the bushing equipped holes 126 which are provided in the lateral flanges 124 on the end walls 110 of the drag flask sections 20 and which also cooperate with the downwardly projecting or depending pins 158 on the match plate 22. Insofar as the leader pins 202&#39; are concerned, their spacing must, therefore, be equal to the spacing of the pins 158 on the match plate.  
  An important difference between the lower turntable spider 82 for supporting the drag flask sections 20 and the upper turntable spider 80 for supporting the cope flask sections 18 resides in the provision of pairs of anti-friction wear liners 210 which are disposed in opposed relationship on the inner sides of the parallel side bars 190&#39; of the lower spider arms 182. These antifriction wear liners define therebetween radially extending guide slots and cooperate in a manner that will be set forth subsequently with the aforementioned Geneva mechanism 32 for turntable-indexing purposes.  
  Additional components on the lower turntable spider 82 which are not present on the upper spider 80 are a series of four turntable-stabilizing and locating sockets 212. The latter are formed in four brackets 214 which are fixedly mounted on the outer surfaces of the long outer T-heads of the T-shaped brackets 192 at the distal ends of the lower spider arms 182. These sockets are thus disposed 90 apart on the turntable and are designed for successive cooperation with a vertically slid able, hydraulically-operable shot pin 216 (see FIGS. 1 and 2) to stabilize the turntable in between indexing operations in a manner that likewise will be made clear during a subsequent discussion of the Geneva mechanism 32 and the manner in which such mechanism causes turntable-indexing operations. The shot pin 216 is spring-biased in such manner that it is urged upwardly.  
 (The Turntable Drive Mechanism) As previously stated, the turntable 16 is adapted to be periodically indexed throughout an angle of 90 under the control of the Geneva mechanism 32 and its drive motor or actuator 33. This Geneva actuator 33 (see FIGS. 1 to 4, inclusive) may be of any conventional construction. there being several forms of commercially available actuator units which are capable of use in connection with the molding machine 10. One such unit is manufactured and sold by HydraPower, Inc. of Wadsworth, Ohio, and is designated as Model No. 150M.&#34; Briefly, the Geneva actuator 33 embodies four hydraulic cylinders 220 which are arranged in opposed pairs, each pair controlling the longitudinal sliding movement of an internal rack (not shown). A central pinion (likewise not shown) meshes with both racks and carries a vertical oscillatory output shaft 222 which, in the present case, is capable of rotation in opposite directions about an angle of 90. The Geneva actuator 33 is mounted on a supporting bracket 224 which is secured by bolts 225 (see FIG. 4) to the side support 52 in such positional relationship that the actuator 33 underlies the peripheral or circumferential sweep of the arms 182 of the lower turntable spider 82 as clearly shown in FIG. 3 of the drawings. Mounted on the oscillatory output shaft 222 is a Geneva drive arm 226, the distal end of which serves to support an hydraulic cylinder unit 228 by means of which a spring-biased. vertically extending, shot pin 230 with a roller 232 is selectively projected into and withdrawn from the radially extending confining spaces or guide slots which exist between the spaced apart anti-friction wear liners 210 of the lower spider arms 182.  
  It will be understood, of course, that each 90 turntable indexing operation is effected by causing the Geneva drive arm 226 to swing from the full-line position in which it is illustrated in FIG. 1, in a counterclockwise direction as seen in this view through an angle of 90 to the end that the shot pin. 230 and its roller 232 (which normally remain in their upwardly projected, spring-biased position) will ride radially inwardly in the associated guide slot which is provided by the adjacent pair of anti-friction wear liners 210, thus causing the turntable 16 to rotate in a clockwise direction by a simple harmonic motion. At the completion of the drive stroke of the drive arm 226 as shown in dotted lines in FIG. 1, the turntable 16 will have been indexed throughout an angle of exactly 90 thus causing it to shift each pair of flask sections 18 and 20 on the turntable 16 from its present station to the next adjacent or following station for flask-handling or other operations at such latter station. At the completion of such turntable-indexing operation, the hydraulic cylinder unit 228 is energized to withdraw the shot pin 230 with its roller 232 from the adjacent radial guide slot between the wear liners 210 and, during such time as the hydraulic cylinder unit 228 remains energized, the hydraulic Geneva actuator 33 is actuated in a reverse direction to restore the drive arm 226 to its full-line normal position as shown in FIG. 1, after which the hydraulic cylinder unit 228 is deenergized in order to allow the shot pin 230 with its associated roller .232 to be projected into the guide slot which exists between the anti-friction wear liners 210 of the next adjacent lower spider arm 182.  
  In order to stabilize the turntable 16 in between indexing operations of the Geneva mechanism 32, and thus. insure proper flask section alignment with the flask-handling components at the working station WS, the aforementioned shot pin 216 is projected at the completion of each indexing operation into the socket 212 at the distal end of the adjacent lower spider arm 182 where it remains until the commencement of the next succeeding indexing operation. As best shown in FIG. 2, the aforementioned shot pin 216 is extensible and retractible under the control of a cylinder 240 which is secured to the outer side of the side support 52 of the machine framework 14. Thus, immediately before a given indexing operation takes place, the cylinder 240 is energized to retract the roller-equipped shot pin 216. This retraction of said shot pin remains effective during the entire indexing movement of the turntable 16, after which the cylinder 240 is deenergized so as to allow the spring-biased shot pin 216 to enter the socket 212 at the distal end of the succeeding lower spider arm 182 which has been brought into vertical alignment with such shot pin.  
 THE HYDRAULICALLY-OPERABLE RAM ASSEMBLY The hydraulically-operable ram assembly 34 appears in outline FIG. 2 and in detail in FIGS. 12 to 22, inclusive. This ram assembly is supported on a platform 242 (SEE FIG. 2) which extends between the horizontally. spaced apart, side bars 59 of the machine framework 14. Such platform supports the ram assembly so that it is centered within the working station WS with the result that it is properly aligned with the various flaskhandling and other instrumentalities at this station.  
  As shown in FIG. 12 and also subsequent views, the ram assembly 34 embodies a vertically extending, central lift plunger 250 on the upper end of which there is fixed, mounted or secured a lower drag section squeeze plate 252. The lift plunger 250 is surrounded by a fixed, vertically extending, cylinder body 254 within which the plunger operates with a vertical sliding action. The upper end of the cylinder body 254 is open and the lower end is provided with a closure wall 256. As shown in FIG. 12, an oil inlet port 258 is formed in the cylinder body 254 in the vicinity of said closure wall 256. The lower drag squeeze plate 252 is formed with a downwardly extending tubular floating plunger 260 which is surrounded by an outer lift sleeve 262. The latter is slidable vertically to a small extent relatively to the floating plunger 260 and is provided with an upper. vertical, continuous rectangular wall 264 and also an inner, horizontal, upwardly facing, ledge-like surface 266 on which the lower drag section squeeze plate 252 normally seats or rests as shown in FIGS. 13 to 17, inclusive. When oil under pressure is supplied to the cylinder body 254 through the port 258, the lift plunger 250 together with the floating plunger 260 and the lift sleeve raises.  
  The upper rectangular wall 264 constitutes a socalled drag upset and is designed for engagement with the lower open rectangular rim of the superjacent drag flask section during flask-closing, sandsqueezing, and other mold-forming operations and, therefore, this wall 264 and the lift sleeve 262 may be regarded as constituting a lower drag flask section extension, and it will sometimes be referred to hereinafter as such. The central lift plunger 250 functions to control the absolute movements of the lower drag section squeeze plate 252 and the intermediate tubular floating plunger 260. The lift sleeve in response to upward movement of the lift plunger 250 effectively engages and moves the superjacent drag flask section 20 during handling of the various pairs of flask sections at the working station WS.  
  An upper oil port 267 is formed in the upper region of the lift sleeve 262 and leads to the upper end of an annular chamber 268 which exists between said lift sleeve and the tubular floating plunger 260, and a lower oil port 269 is formed in the lower region of the lift sleeve 262-and leads to the lower end of said annular chamber 268. The region of the tubular floating plunger 260 between the two oil ports 267 and 269 is enlarged in order to form a piston 270 which operates in an internal recess 272 in the wall of the lift sleeve 262 as well as in the aforementioned chamber 268. The ports 267 and 269 are adapted to be connected by flexible oil lines (not shown) to a source of oil under pressure with the flow of oil through such lines being regulated by suitable control valves (also not shown). When oil under pressure is admitted into the lower end of the chamber 268 via the lower oil port 269 while the upper oil port 267 is in a vented condition, the lift sleeve 262, together with the rectangular wall 264 (drag upset), moves downwards with respect to the tubular floating plunger 260 and the lift plunger 250, and when oil under pressure is introduced into the upper end of the annular chamber 268 by way of the upper oil port 267 and the lower oil port 269 is in a vented condition, the lift sleeve 262, together with its upper vertical continuous rectangular wall 264, moves upwards with respect to said tubular floating plunger 260-and the lift plunger 250.  
  The operation of the ram assembly 34, i.e., the specific and relative movement of the central lift plunger 250, the drag flask section control plunger 260 and the lift sleeve 262, which take place during the machine cycle will be described in detail when the operation of the sand mold-forming machine 10 is set forth in detail subsequently. However, for the present, it is deemed sufflcient to state that the admission of oil under pressure to the port 258 in the lower end of the stationary cylinder body 254 will serve forcibly to slide the lift plunger 250 upwardly, thus positively forcing upwards the lower drag squeeze plate 252 and the floating plunger 260. Such upward movement of the lift plunger 250 will impart upward movement to the aforesaid drag section extension (lift sleeve 262 and drag upset or rectangular wall 264) by reason of the column of oil which is trapped within the upper end of the chamber 268 between the floating plunger 260 and the lift sleeve 262. The admission of oil under pressure through the port 269 will force the lift sleeve 262 downwardly with respect to the tubular floating plunger 260 as previously pointed out. It should be borne in mind when the operation of the machine is set forth in detail subsequently, that when either oil port 267 or 269 is employed as an inlet port to admit oil to the chamber 268, the other port will function in the manner of an outlet port to allow oil to escape from said chamber.  
  As shown in FIG. 2 of the drawings. the lift sleeve 262 of the ram assembly 34 carries a horizontal bar 274 from which there project upwardly a pair of pilot or leader pins 276. The latter are designed for cooperation with the aforementioned holes 122 which are associated with the superjacent drag flask section 20 as shown in dotted lines in FIG. 1. When the leader pins 276 are shifted upwards into the holes 122, the superjacent drag flask section 20 is held against lateral displacement with respect to the ram assembly 34.  
 THE UPPER PLATEN ASSEMBLY As previously stated, the ram assembly 34 cooperates with the upper platen assembly 35 (see FIG. 2) during flask-handling operations at the working station WS and particularly during the squeeze operation wherein the lower squeeze plate 252 compresses the previously &#39;compacted sand in the associated cope and drag flask sections as shown in FIGS. 17 and 18 of the drawings. This upper platen assembly 35 includes a fixed or stationary platen proper or upper squeeze plate 280 which is supported in the upper region of the machine framework 14 and normally is encompassed by a rectangular cope upset frame 284. The lower rim of said cope upset frame is designed for edge-to-edge engagement with the upper rim of the subjacent cope flask section 18 during the squeeze operation as shown in FIG. 18. The cope upset frame 284 is vertically slidable on a pair of vertically extending guide rods 286 (see FIG. 2), and immediately after the squeeze operation, two doubleacting hydraulic cylinders 288 having verticallyslidable plungers 290 associated therewith are adapted to be actuated to restore the cope upset frame 234 to its upper retracted position as shown in FIGS. 12., 19, 20, 21 and 22. When the cylinders 288 are reversely or oppositely actuated, the plungers 290 slide downwards with the result that the cope upset frame 284 is shifted downwards into the position in which it is shown in FIGS. 13 to 17, inclusive.  
 THE FLASK-STRIPPING MECHANISM The stripping mechanism which is disposed at the moldstripping station SS is illustrated in FIGS. 1. 2, and 24 to 32, inclusive. It is adapted effectively to receive in a separated condition a pair of sand-filled and compacted cope and drag flask sections 18 and 20 after such pair has been moved throughout a 90 are from the core-setting station CS to bring the two separated flask sections together in order to assembly or unite the cope and drag sand mold parts (designated cm and dm in the drawings) which are contained in the flask sections 18 and 20, respectively, to provide a bottom board support for the assembled mold, and finally to push the assembled flask sections bodily as a unit from the assembled composite sand mold cm and dill, leaving the latter resting on the bottom board.  
  During the following discussion of the flask-stripping mechanism at the stripping station SS, it should be borne in mind that this mechanism as disclosed in FIGS. 24 to 32 is purely schematic in its representation and the disclosure of these views does not necessarily correspond to the structural details of FIGS. 1 and 2.  
  Referring now particularly to FIGS. 1 and 2 of the drawings, the flask-stripping mechanism involves in its general organization a pair of vertical guide rods 300, the latter being disposed in spaced apart relationship transversely of the stripping station SS and also being supported at their upper and lower ends by angle brackets 302 and 304 which are fastened, respectively. to the intermediate transverse bars 72 and 70 of the machine framework 14. Slidable vertically on the guide rods 300 is a stripping carriage 306 which comprises a horizontal platform 308. The latter is provided at its inner corners with two tubular guide sleeves 310 which encompass the guide rods 300 and slide vertically thereon. The carriage 306 is vertically shiftable under the control ofa vertically slidable plunger 311 which is associated with the aforementioned hydraulicallyoperable primary stripping cylinder 36. The carriage 306 further includes or comprises on the upper surface of the platform 308 a pair of spaced apart. horizontally extending skids 312, the latter being adapted to receive thereon the aforementioned bottom board 24 as it is fed thereto from a stack S under the control of a suitable ejector mechanism (not shown). The skids 312 serve to maintain the boards 24 in an elevationed position above the effective level of the platform Additionally, the carriage 306 serves to support the aforementioned four secondary flask-stripping cylinders 38. The latter depend below the platform 308 of the carrige M16 and have vertically-slidable stipping plungers 316 which project vertically upwardly above the effective level of said platform and which, normally, in their retracted position, underlie the effective level of the skids 3122. Upon energization &#39;of the secondary cylinders 33, the plungers 316 are adapted to be projected upwardly to the position wherein they are illustrated in FIGS. 28, 29 and 30 so that the upper or distal ends thereof are disposed above the level of the skids 312 for the purpose of engaging and raising the superjacent cope flask section 18 for flask-stripping operations as will be made clear presently when the operation ofthe machine is described hereafter.  
  The carriage 306 is shiftable vertically upwardly on the guide rods 300 from the lowered position in which it is shown in FIGS. 2 and&#39;24 wherein the bottom board 24 is disposed an appreciable distance below the level of the superjacent drag flask section 20 which has been brought into position at the stripping station 58 by the lower turntable spider 82 of the turntable 16 in order that such bottom board will pick up the drag flask section 20 and force itupwardly against the superjacent cope flask section 18 and then carry both flask sections further upwardly so that the thus assembled mold parts cm and dm within the two flask sections will be projected against the aforementioned stationary reaction platen 26 and held there while the plungers 316 of the cylinders 38 perform their flask-stripping operation. The platen 26 is fixedly mounted on a bracket 318 (See FIG. 2) which is suitably mounted on the side bars 64 of the machine framework 14. Such vertical movement of the carriage is effected under the control of the aforementioned hydraulically-operable primary cylinder 36, the latter being fixedly secured to the upper portions of the corner posts 68 of the framework 14 by means of a clamping bracket 319.  
 OPERATION OF THE MACHINE (General Considerations) In reciting the operation of the present sand moldforming machine, since the four paired cope and drag mold flask sections 18 and 20 shift simultaneously in a circular path throughout an arc of during each indexing operation of the turntable 16, with each pair of flask sections returning to its original position at the end of a complete machine cycle. it will be considered that one complete machine cycle involves four such indexing operations with a complete revolution of each pair of flask sections taking place about the central ver&#39; tical axis of the turntable. Considering the machine at the time any given run of composite sand molds is to be effected and with four pairsof empty flask sections in the machine at the four stations WS, CS, SS and DS, the first quarter cycle involves handling of a pair of flask sections at the working station SS to the point where the sand blow operation is effected, and then further handling of such sections to the point where the completed cope and drag sand mold parts are contained in the spider-supported cope and drag flask sections 18 and 20, followed by the shifting of the pair of sandfilled and compacted cope and drag flask sections 18 and 20 from the working station WS to the coresetting station CS, the shifting of a second pair of initially empty flask sections from the core-setting station CS to the stripping station SS, the shifting ofa third pair of initially empty flask sections from the stripping station SS to the idle or dwell station DS, and the shifting ofa fourth pair of initially empty flask sections from the dwell station DS to the working station WS to replace the first pair of flask sections which were transferred in a sand-filled and compacted condition from such station to the core-setting station CS.  
  The second quarter cycle of machine operation involves the production of a second pair of mold parts as the working station WS followed by transfer thereof to the core-setting station CS; the manual setting ofa core at the core-setting station by placing the core on the formed drag mold part then at such station. and the transfer of the mold parts with the set core to the stripping station SS; the transfer of an initially empty pair of mold sections from the mold-stripping station SS to the dwell DS; and the transfer of an initially empty pair of mold sections from the dwell station DS to the working station WS.  
 , The third quarter cycle of machine operation involves the production of a third pair of cope and drag mold parts at the working station WS and their transfer to the coresetting station CS; the transfer of the second pair of juxtapositioned core-equipped mold parts and their respective separated flask sections from the coresetting station to the stripping station; the assembly of a pair of mold parts. the placement of the assembled mold on a bottom board at the stripping station of the bottom board; and the transfer of a pair of empty flask sections to the dwell station; and the transfer of a pair of empty flask sections from the dwell station DS to the working station WS.  
  The fourth quarter of the machine cycle involves the production of a fourth pair of mold parts at the working station WS and transfer thereof to the core-setting station CS; the setting of a core in the juxtapositioned third pair of mold parts at the core-setting station and the transfer thereof to the stripping station SS; the assembly of the second pair of mold parts; the ejection of the second mold on a bottom board at the stripping station. and the transfer of the empty flask sections to the dwell station; and the transfer of empty flask sections from the dwell station to the working station WS.  
  Because the machine commenced its operation with four pairs of empty cope and drag flask sections 18 and 20., only two completed composite molds were discharged from the machine at the stripping station SS during this first cycle of operation. However. with filled flask sections remaining at the core-setting station CS and with fulled flask sections remaining at the stripping station at the end of the first complete molding machine cycle. the second cycle. as well as all succeeding cycles. will be productive of four complete molds. each positioned on a bottom board.  
 (Turntable-Indexing Operations) As previously pointed out, turntable indexing operations take place at the end of each quarter-cycle of machine operation although the net result would be substantially the same if such operations were caused to take place at the beginning of each quarter cycle. Such turntable indexing is initiated by energizing the hydraulic cylinder unit 228 at the distal end of the Geneva drive arm 226 (see FIGS. 1. 2 and 4) in order to project the roller-equipped. spring-biased shot pin 230 into the guideway or guide slot which exists between the antifriction wear liners 210 of the adjacent lower spider arm 182, after which the Geneva actuator 33 is supplied with oil under pressure in order to actuate the same and effect swinging movement of the Geneva drive arm 226 in a counterclockwise direction and consequent swinging movement of the associated or adjacent spider arm 182 in a clockwise direction in the usual manner of conventional Geneva drive mechanisms, thus causing the turntable 16 as a whole to rotate throughout an angle of 90. At the end of the Geneva arm movement, the cylinder 240 (see FlG. 2) is actuated so as to cause the shot pin 216 to be projected 20 upwardly into the adjacent and overlying locating socket 212. thus locking the turntable in its indexed position. In such position, two adjacent pairs of upper and lower spider arms 180 and 182 are in proper position at the working staton WS for flask-handling movements at such station.  
 (Machine Functions at the Working Station) A schematic representation of the various machine functions which take place at the working station WS is illustrated in FIGS. 12 to 21, inclusive. In these views, substantially all of the machine framework has been omitted in the interests of clarity and the representation of the cope flask section 18, the drag flask section 20, and the match plate 22 has been simplified by the omission of such flask or match plate adjuncts as the flask-supporting flanges, vents or screen units, blow slots. leader pins. and the like. Furthermore, no portions of the flask-supporting spider arms 180 and 182 have been shown.  
  In the start position of the molding machine 10, all of the components of the ram assembly 34 assume the positions in which they are shown in FlG. l2 and at the commencement of any given machine cycle. oil under pressure is admitted to the port 267, thus causing the lift sleeve 262 (lower drag flask section extension) to rise relatively to the lower squeeze platen 252 to the position of FIG. 13. At the same time. the cylinders 288 are actuated to lower the rods 290 and cause corresponding movement to the cope upset frame 284. The associated cope and drag flask sections 18 and 20 remain supported. respectively. on the upper and lower turntable spiders and 82. Oil under pressure is then admitted to the port 258 at the lower end region of the vertically extending cylinder body 254, thus driving or forcing the central lift plunger 250 upwardly and causing the lift sleeve 262 and said plunger 250 to rise in unison so that the rim of the rectangular wall or drag upset 264 forming part of the lift sleeve 262 (drag flask section extension) engages the lower rim of the superjacent flask section 20 as shown in FIG. 14. Continued upward movement of the lift sleeve 262 and the plunger 250 in unison raises the superjacent drag flask section 20 and bring the upper rim thereof into engagement with the lower surface of the match plate 22 as also shown in FIG. 14. As the lift plunger 250 and the&#39; lift sleeve 262 rise still further, the match plate 22 is forced upwardly so as to engage the lower rim of the turntable-supported superjacent cope flask section 18 as shown in FIG. 15. The supply of oil under pressure to the port 258 is continued until the lift plunger 250, the lift sleeve 262, the drag flask section 20, the match plate 22, and the cope flask section 18 have all moved upwardly to bring the upper rim of the cope flask section into engagement with the lower rim of the cope upset frame 284 as shown in FIG. 16.  
  At this time. the blow operation is initiated by blowing sand simultaneously through two distribution heads 350 and 352 (see FIG. 17) into the mold cavities in the two flask sections 18 and 20. The distribution head 350 extends downwards through the upper squeeze plate 280, and the distribution head 352 extends laterally through the blow slot 130 in one of the end walls of the drag flask section 20. The blowing of sand is continued until the two mold cavities within the two flask sections are filled and the blown sand is compacted in a preliminary manner in said flask sections. During the blow operation. the lower drag section squeeze plate 252 is locked in place by the column of oil in the lower interior portion of the cylinder body 254. the lift sleeve 262 is locked in place or against vertical displacement by the trapping of oil under pressure in the upper por- 1 tion of the chamber 268 and the cope upset frame 284 is locked against vertical displacement by locking the plungers 290 in their down position through the medium of proper operation of the double-acting cylinders 288. The manner in which sand issuing from the hopper 76 is caused to pass through the shut-off gate mechanism 78 and the magazine 75 is not illustrated in the drawings, only the distribution heads 350 and 352 being disclosed. These sand-feeding instrumentalities are substantially the same as corresponding instrumentalities which are shown and described in aforemen tioned US. Pat. No. 3,648,759 and reference may be had to such patent for a full understanding of such instrumentalitiesv After completion of the blow operation and the cavities in the two flask sections have been filled with compacted sand, the oil pressure at the port 267 is relieved,  
  while at the same time the oil pressure in the two hydraulic cylinders 288 is also relieved. At this time, continued upward movement of the lift plunger 250 and the lower squeeze plate 252 causes further compacting or compressing of the sand in the drag flask section cavity against the match plate 22 which, in turn, further compacts or compresses the sand in the cope flask section cavity against the upper platen or squeeze plate 280, thereby effecting the squeeze operation and producing completed cope and drag mold parts cm and (fill in the mold cavities in the drag and cope flask sections. In connection with this squeeze operation. it is to &#34;be noted that a sprue 354 (see FIGS. 12 to 22, inclu- ;.sive) which establishes the usual sprue passage leading V to the upper mold part cm is of a telescopic nature in order that it will not be pinched between the aforementioned upper pattern part 140 and the upper platen or squeeze plate 280.  
  The aforementioned squeeze operation is followed by actuation of the cylinders 288 so as to move upwards the cope upset frame 284 (see FIG. 19) and also to effect a pattern draw operation wherein oil pressure at the port 258 is relieved while oil under pressure is supplied to the port 269. This has the effect of causing downward retraction of the lift sleeve 262 with respect to the lower or drag squeeze plate 252 and also causing the lift plunger 250 and its associated squeeze plate 252 and tubular floating plunger 260 to shift downwardly, thus lowering the two flask sections 18 and 20, together with the now-completed cope and drag mold parts cm and dm, away from the upper platen or squeeze plate 1rest on the match plate supporting bracket I52 as {shown in FIG. 20, while still further downward movement of the lift plunger brings the drag flask section 20 to a position of rest on the adjacent pair of lower spider arms 182 and the various flask and ram components assume the positions in which they are shown in FIG. 21. It is to be noted that, in this view, the various flask and match plate positions. as well as the condition of the ram assembly 34, are identical with the disclosure of FIG. 12 except for the fact that in FIG. 12 the flask sections 18 and 20 are empty. However, at the completion of the first quarter cycle of machine operation, the cope and drag flask sections 18 and 20 with the cope and drag mold parts cm and zlm therein will be shifted out of the working station WS while an empty pair of flask sections will be conducted into such station as shown in FIG. 22, this latter view representing the positions of the flask sections at approximately in the 360 total machine cycle.  
 (Machine Functions at the Core-Setting Station) At the end of the first quarter cycle of machine operation and after the mold parts and the flask sections which encompass them have been transferred to the core-setting station CS as shown in FIG. 23, no automatic flask handling or other operations take place. such station constituting, in effect. a dwell area where, if desired, a core such as the core 360 may be manually positioned in place on the drag mold part (In: while the latters encompassing drag flask section 20 rests on the two adjacent lower spider arms 182, it being understood that when the two flask sections are disposed at the coresetting station C5. the cope flask section 18 is in raised or separated relation with the drag flask section 20. The only machine function which occurs at this station CS is a movement of the flask sections 18 and 20 into such station at the end. of the first quarter machine cycle and a movement of these flask sections away from the station CS at the commencement of the second quarter cycle of machine operation.  
  It is to be noted that this point that. unlike a conventional match plate molding machine where core setting operations are performed at a main working station where vertical flask movements are carried out in the performance of the squeeze and other operations, the core setting operation of the present machine is carried out at a region remote from the working station where the cope and drag flask sections are fixedly supported at different levels and are thus incapable of closing upon each other so that there will be no danger to the hands of the operator incident to closing of the mold flask sections upon each other.  
 (Machine Functions at the Stripping Station) Referring now to FIGS. 24 to 32, inclusive, FIG. 24 represents the positions of the machine parts at the commencement of the third quarter machine cycle. At this time, the bottom board supporting platform 308 of the vertically-movable carriage 306 remains in its lowermost position with a prepositioned bottom board 24 resting on the skids 312 while the mold-containing flask sections 18 and 20 are disposed in their spaced apart positions on the adjacent pairs of upper and lower spider arms 180 and 182 which support them.  
  Flask-handling operation at the mold-stripping sta tion SS are commenced by supplying oil under pressure to the primary stripping cylinder 36 so as to retract the plunger 311 thereof, thereby raising the platform 308 until the bottom board 24 thereon engages the underneath surface or side of the drag pattern part dm as