US2762092A

US2762092A - Turntable type machines for forming shell molds

Info

Publication number: US2762092A
Application number: US299606A
Authority: US
Inventors: Klamp Paul; Leonard J Bishop
Original assignee: Mechanical Handling Systems Inc
Current assignee: Mechanical Handling Systems Inc
Priority date: 1952-07-18
Filing date: 1952-07-18
Publication date: 1956-09-11
Anticipated expiration: 1973-09-11

Description

Sept. 11, 1956 P. KLAMP ErAL TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS l3 SheetsSheet 1 Filed July 18, 1952 IN VEN TOR.S P404 42 am Z. BISHOP BY M w\ nia.

ATTOi/WF/J- Sept. 11, 1956 P. KLAMP ETAL TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS Filed July 18, 1952 13 Sheets-Sheet 2 INVENTORJ 1 ,404 AZ/MP Z. E/Jf/OP BY Sept. 11, 1956 P. KLAMP EI'AL TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS l3 Sheets-Sheet 3 Filed July 18, 1952 M m w M Z w m 6 w r m \yp/v mmm WA Ea wJ M4. Y .T I d V B 7 6 Ill Sept. 11, 1956 P. KLAMP ETAL TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS l3 Sheets-Sheet 4 Filed July 18, 1952 INVENTORS A: 0.2 AAHMP p 11, 1956 P. KLAMP ETAL 2,762,092

TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS Filed July 18, 1952 13 SheetsSheet 5 Sept. 11, 1956 P. KLAMP ETAL 2,762,092

TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS Filed July 18, 1952 13 Sheeis-She'et e Sept. 11, 1956 P. KLAMP EI'AL 2,762,092

TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS Filed July 18, 1952 13 Sheets-Sheet 7 INVENTORJ P40 AZAMP 4. J. 6/67/01 BY ATTOP/VAVJ Sept. 11, 1956 P. KLAMP EIAL E TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS Filed July 18, 1952 1:5 Sheet s-Sheet 8 1 -llI] :13: :L 4 IJIVVENTORJ P1904 A: AM?

4. v. emu/0P Sept. 11, 1956 PLKLAMP ETAL 2,762,092

TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS Filed July 18,, 1952 13 Sheets-Sheet 9 INVENTORJ p404 A1 /9MP B LU v T TURNTABLE TYPE MACHINES FDR FORMING SHELL MOLDS Filed July 18, 1952 Sept. 11, 1956 P. KLAMP El'AL 1s sheets-sheet 1o 77 l as! Se t. 11, 1956 P. KLAMP EIAL, 2,762,092

TURNTABLE TYPE MACHINES FOR FORMING swam, MOLDS Filed July 18, 1952 16 Sheets-.Sfie et 11 mum 13 Sheets-Sheet l2 P. KLAMP ETAL TURNTABLE TYPE MACHINES FOR FORMING SHELL MOLDS Filed July 18, 1952 Sept. 11, 1956 F \R, 50% wow Sept. 11, 1956 P. KLAMP ETAL TURNTABLE TYPE MACHINES FOR FORMING SHELL. MOLDS l3 Sheets-Sheet 13 Filed July 18, 1952 LI lilllllll llllllllllll |I|| United States Patent TURNTABLE TYPE IVIACHINES FOR FGRMIN G SHELL MOLDS Paul Klamp, Detroit, and Leonard .l'. iiishop, Birmingham, Mich assignors to Mechanical Handling Systems, Inc., Detroit, Mich, a corporation of hfichigan Application July 18, 1952, Serial No. 299,606

52 Claims. (Cl. 22-21) This invention relates to machines for forming molds of the type known in the founding industry as shell molds, which are made by a process which involves the steps of depositing a layer of thermosetting mold forming material upon a heated pattern plate, curing the mold in an oven, and then stripping the mold from the pattern plate as the latter emerges from the oven, leaving the pattern plate in a heated condition to receive a new coating of mold forming material.

The term turntable is used to designate the type of machine of the invention due to the fact that the general arrangement of the machine involves the mounting of a plurality of pattern carriers, each adapted to receive a pattern plate, upon a turntable mounted for rotation on a vertical axis. Rotation of the turntable passes the pattern carriers by areas in which the essential steps of the shell molding process are performed, including a mold forming area, a stationary oven through which the pattern carriers travel for curing of the mold, and a mold stripping or ejector station.

The material of which the mold is formed is held in a container having an opening adapted to be covered by a pattern plate during the mold forming operation. With this opening so covered, the container is inverted over the pattern plate to deposit mold forming material all over the heated surface thereof, and then, the pattern plate is positioned above the container so that the excess material falls back into the container. This method of applying the mold forming material has been found to be perhaps the most satisfactory devised at the present time because it keeps the mold forming material under confinement, a feature very necessary due to the powderhe, dust-forming nature of the material.

This general method has been followed in machines previously constructed. For example, in one such prior machine of the turntable type, the mold forming material is applied by: 1

1. Turning the heated pattern plate upside down;

2. Moving a separate mold material container upward against the pattern plate;

3. Clamping the container to the pattern plate or pattern plate holder;

4. Lowering the container support to provide space for turning the container upside down;

5. Inverting the clamped container-pattern plate unit, superimposing the container above the pattern plate to deposit mold material over the surface of the pattern plate;

6. Reversing the position of the clamped unit again, moving the container'below the pattern plate with the excess mold material falling back into the container;

7. Raising the container support until it contacts the bottom of the container;

8. Loosening the clamps;

9. Lowering the container; and

10. Turning the pattern plate right side up again.

A machine operating in this fashion has several inherent disadvantages. First of all, the large number of successive motions of the various parts requires a large number of operating mechanisms and controls. Secondly, the hinge axis for inverting the pattern plate and mold material container is in such proximity to the pattern plate that it is not possible to move the pattern plate through an oven for curing the mold resting on the pattern plate, without moving the hinge bearings and some of the operating mechanisms for inverting, such as gears and racks, through the same oven, too. This makes it impossible to maintain proper lubrication on the bearing surfaces of the operating parts, and more heat is lost from the oven, being carried out by such parts. Furthermore, turning the pattern plate upside down after the mold material has been deposited thereon creates a tendency of parts of the newly formed mold to fall off.

Finally, when the pattern plate and container of mold material are inverted to the position Where the pattern plate is below the container, the mold forming material is not level. Its upper. surface is inclined at the angle of repose, usually 35 to 40. Consequently, one side of the level pattern plate is covered to a lower height than the other side, resulting in lack of uniformity of the product.

The present invention, therefore, is directed to correcting these more obvious disadvantages together with the attainment of additional new and useful features for these machines by a new combination and arrangement between the parts which comprise a molding unit, that is, a pattern carrier and molding material container and between a molding unit, a turntable, an oven, and mechanism for motivating the parts.

The more important features of the invention are: first, a mold forming unit wherein the pattern carrier and material container are hinged for movement about a common axis, this axis being located remotely from the position of a pattern plate in a carrier, and located remotely from the oven of .the machine. This results in a much simplified operation of the parts. In combination with the oven design it enables all major operating parts of the machine to be kept out of the oven heat. In combination with a new design of material container, it enables the amount of motion of the parts to be re duced considerably and, at the same time, results in greater uniformity of the finished product.

Second, a pattern carrier mounted on a turntable which supports the pattern plate in a normal horizontal position projecting outwardly from the circumference of the turntable, in combination with a semicircular oven arranged around the turntable and having a continuous slot in its vertically disposed inner wall. The pattern carrier projects into the oven through this slot and positions the pattern plate within the oven. Means are preferably provided to seal the vertical slot in the oven wall. This arrangement subjects a minimum number of parts of the machine to the direct heat of the oven and also improves the efficiency of the oven by reducing the heat loss through radiation and also through the amount of heat absorbed by the parts passing through the oven.

Third, a motivating mechanism and arrangement for moving all of the parts of the machine through their cycle from a single source of motive power so that the machine operates as a single geared unit in contrast to a unit employing multiple sources of motive power with necessary interlocking controls for governing the sequence of operation.

Fourth, basic relationships between the principal parts of the machine, as briefly outlined above, which can readily be applied to the construction of machines of various sizes, having varying capacities and rates of production.

Many other features are present in the machines of the invention which can only best be appreciated "from a consideration of specific constructions. These features and the main features pointed out above are incorporated in the machines illustrated in the accompanying drawstruction is an intermittently operating turntable type machine illustrated in Figs. 24 through 27.

'The individual views comprising these drawings are described as follows:

7 Fig.1, a plan view of the machineshowing the turntable, its driving mechanism, the oven, the ejector, and two of the pattern carrier-containermolding units. In the actual machine, these,rnold forming units are duplicated at equal intervals around the circumference of the turntable, the complete number being eliminated from this figure in order'that other constructional details of the machine would be'apparent; g i

Fig. 2, a sectional view of the machine taken along the line 22 of Fig. 1 showinghalf of the turntable, its

supporting structure and drive unit, and the relationship between turntable and oven and between the carrier and container components of the mold forming unit while tainer as a mold forming unit carried by the turntable passes the location of this section line;

Fig. 4, a section taken along the line 44 of Fig. 1 showing the relationship between carrier and container as a mold forming unit passes this section line, the container being invertcd'over the carrier. Position of carrier and container at maximum'degree'of inverted movement, is indicated in phantom. The'mold forming unit occupies this position a few degrees of turntable rotation in advance of the location of the section-line 4-4;

Fig. 5, a section taken along the line 55 of Fig. 1 showing the relationship between the container and car tier of a mold forming unit and the relationship between the latter and the ejector mechanism as this mechanism is operating to strip a mold from a pattern plate;

Fig. 6, a side elevation of the ejector mechanism shown r mold torrningcycle; 1 a

, Fig. 22, aneievation taken'along the line 22--221or".

in 5,- the pattern carrier being sectionalized in this view to more clearly illustrate the operation of the parts during stripping;

Fig. 7, a section taken along the hne 7--7 of Fig. 1 illustrating the construction and operation of a feeding device for replenishing the supply of mold forming material, and also illustrating the relationship between the carrier and container units while passing the location of this section line;

Fig; 8, a detail taken along the line 88 of- Fig. '7 showing a cam controlled device for actuating the feeder mechanism;

Fig. 9, an enlarged detail in plan taken in the direction ofthe arrows 9+9 of Fig. 4 showing a camming device for permitting movement of the mold forming unit to the maximum inverted position indicated in Fig. 4;

Fig. 10, a plan view, partly in section, containing an enlarged showing of a pattern carrier with a pattern plate mounted therein;

Fig. 11, an enlarged detail taken along the section line 11-11 of Fig. ,10; I s

Fig. 12, an enlarged detail taken along the section line 12-12 of Fig. 10.

*Fig. 13, a sectional detail of the mold forming unit support taken along the line 13-13 of Fig. 10 and showing this support in assembled relationship with the turntable;

Fig. 14, an enlarged detail taken along the line 14-14 of FigmlO;

headings.

Fig. 15, a sectional detail taken along the line 15-15 of Fig. 10; v V

Fig. 16, a side elevation taken along the line 16l6 of Fig. 1 showing a cam track for controlling pivotal movement of the carrier and container of a mold forming unit during the mold formingoperation;

Fig. 17, an enlarged detail of a cam actuated latch for engaging a pattern carrier to a container during the mold Fig. 19, a plan view of an alternate form of continu ousiy rotating turntabletype machine showing the mold forming segment thereof. In this view, the .molding units are -indicatied in phantom, and many. details previousiyillustratedin the machine of Figs. 1 .to'18 are eliminated tor the sake of simplicity and clarity;

Fig. 20,- an elevation showing the. cam tracktor controlling the mold forming operationof the machine of Fig.9; f

Fig. 21, an elevation taken along the line 21.-21 of Fig. 19 showing the materialcontainer and pattern carrier inthe relative position occupied at the beginning of the Fig. 19 showing the relationship .between the parts of the mold forming .unit at the positionof this section line;

Fig. 23, an elevationtaken along the line 2323 of Fig. 19 showing the relationship between the parts of the machine after thefmold' forming operation has beencompleted and thefpattern carrier has passeduinto the a Fig. 24,

four stations of this machine are shown, the fourthstation notbeing illustrated in full :due to the fact that in this particular machine-that station is a second curing station where the parts are in the oven in the same man nor as are the parts shown in dot-dash lines;

Fig. 25, anelevationtaken along the line 25-25 or" t Fig. 24' and 'showing in section both the 'mold forming station of the'machine and one of thecuring stations;

Fig. 26,.an'elevation taken alongtheline'2t3 -?.6 of Fig. 24- sllowingftheejector station and a portion of the turntable drive of the machine; and

Fig. 27, an end elevation of-the cam'which operates the parts through the molding cycle.

In the following detailed description of the invention the two general constructions -continuously rotating turntable machine and intermittently rotating turntable machine will be described separately under these general coNrrnUoUsLY norAr-nsto TURNTABLE MACHINE (Figs. 1 to 23) Due to the relative complexity of this machine, it is believed that a more adequate and understandable description of the construction thereof can be obtained by considering its major component parts individually. This is particularly truevbecau se of the fact that the constructional features of many'ofthese'major parts are common to the invention regardless of the'size of the machine or whetherthe machine employsa'co'ntinuously or intermittently rotating turntable.

be amplified by an over-all description of the operation.

of the machine.

a plan view of an intermittently rotating turntable type of'machine of the invention. Threeof the' Turntable and drive unit (Figs. 1 and 2) The turntable consists of a pair of

hub plates

21 and 22 each connected to a number of spokes 23 which extend radially from the center of the turntable at equal intervals. A center bearing 24 is carried by the lower hub plate 22 and receives a spindle 25 forming part of a pedestal assembly 26 which defines the rotational axis of the turntable. At their outer ends each adjacent pair of spokes 23 are interconnected by a channel ber 27 secured to their upper flanges, and by a sprocket segment 28 secured between a roller 29 and spacer 30, to their lower flanges. A circular rail 31 is positioned beneath the rollers 29 and supports the major portion of the weight of the turntable. The channel member 2'! serves as a support for each of the molding units and each of these channel members is braced by a sheet metal panel 32 having one end secured to the upper fiange 33 of the channel member 27 and its other end secured between the upper flanges of an adjacent pair of spokes 23. The panel member 32 also acts to define and support the container in its normal position and is provided with a supporting pad 34, preferably of resilient material, which is contacted by the container.

When the foregoing parts of the turntable are assembled, the sprocket segments 28 together form a complete circular sprocket positioned below the spokes of the turntable, and a caterpillar type of driving unit is provided to rotate the turntable by engagement with this sprocket. This drive unit, which is formed of conventional components, is not shown in detail, but its major parts are illustrated in Fig. l and comprise a motor 4%, coupled by a shaft 41 and overload clutch 42 to a re ducer 43. The output shaft of this reducer extends vertically and is provided with a driving sprocket 44. A driving chain 45 is trained around this sprocket and around a similarly disposed sprocket 46 forming part of a take-up unit 47. A portion of the chain 45 intermediate the driving and take-up sprockets engages the sprocket segments 28 of the turntable and a backup roller 49 is preferably employed to maintain the chain in driving engagement with the sprocket segments 28 and to define a sufficient degree of wrap-around.

This driving unit, then, is thus adapted to rotate the turntable on its supporting spindle 25 and supporting rollers 29. The principal component parts of the machine carried by the turntable and rotating therewith are the molding units. Other major component parts such as the oven, ejector and feeding mechanism are stationary.

Molding unit Each molding unit consists of a support assembly, a pattern carrier, and a container for holding a quantity of mold forming material, the carrier and container being pivotally mounted upon a support assembly. in this machine, the support assembly is secured to the turntable.

Considering first the support assembly, and comparing Figs. 3, l3 and 10, the main member of this assembly is a cast pedestal member 59 formed with a housing 51 of semicircular cross section at its upper end. The lower portion of the housing is provided with two ver ieally extending flanges 52 (Fig. 3) adapted to straddle the outer face of a channel 27 of the turntable, and the housing is attached to the channel 27 at a location nn'dway between a pair of adjacent spokes 23 of the turntable by bolts 53 (Fig. 13). A pair of bearings 54 are mounted in holes 55 formed in the side faces of the housing 51 and support a pivot shaft 56. A gear segment 57 is keyed to the shaft 56 and located within the housing 51. This gear segment 57 engages a rack 53, which is T-shaped in cross section (Fig. and which is provided with teeth 59. A pair of vertically extending gibs 6d are secured to the outer vertical face of the pedestal by screws 61, these gibs being located within shoulders 62 formed in such outer face and bordering a vertical slot provided therein. The T section of the rack bar 58 slidably engages these gibs and its teeth 59 engage the gear segment 57. A roller cam follower 63 is secured to the lower end of the rack bar 58, this cam follower contacting a control cam during the mold forming portion of the cycle of the machine to produce vertical movement of the rack bar 58 and consequent rotation of the pivot shaft 56.

Referring to Fig. 13, movement of the rack bar 58 in a downward direction is normally limited by a slide 64 which is held within the channel-shaped base 65 of the pedestal 50 by a plate 66. A cam roller follower 67 is secured to the inner end of the slide 64 by a downwardly extending bracket construction 68. When the slide 64 and rack bar 58 are in the normal position shown in Fig. 13, a limited degree of interengagement is provided between these parts by a detent 69.

The pattern carrier, best illustrated in Fig. 10, is constructed to form a rectangular open framework adapted to receive a pattern plate 70. This framework is defined by left and right

side arm members

71 and 72, respectively, interconnected by a member 73 which forms the inner end wall-of the frame. Each side arm extends inwardly past the end Wall 73 and is provided with a split hub 74 adapted to engage a portion 75 of the pivot shaft 5d and be connected for rotation therewith by a key 76. The outer end of the framework is formed by an end gate 77 which is hinged to the left-hand side arm 71 at 78 and carries a pivoted latch 79 and latch lever 80 which engage a striker 81 secured to the end of the right-hand side arm 72 by bolts 82.

A pattern plate slide 83 is pivotally secured to each of the side arms 7land 72 by a construction illustrated in the detail Fig. ll. Each of the slides 83 is formed with a longitudinally extending inwardly facing groove 84 dimensioned to receive a projecting rib 85 formed on the sides of the pattern plate 76 and is connected to the side arm 71 by a pin 86 having an enlarged head 37 eecentrically formed with relation to the center of the pin 86 as illustrated in Fig. 14. An adjusting and locking bar 88 (Fig. 11) is seated within a notch 89 formed in the portion of the pin which projects outwardly through the side arm 71 and is connected to the pin by a bolt 9% This bar serves to locate the pin 86 axially, and also serves to define the rotational position of the pin through the engagement of the locking bar with a pair of adjusting screws 91 which are threaded in holes 92 formed in an outwardly projecting flange 93 of the side arm 71. Through the adjustment of these screws 91, the pin 86 can be rotated to adjust the position of the pivotal axis of the slide 83 (defined by the eccentric head 87 of the pin) relative to the side arm 71. Pivotal movement of each slide 83 about this pivotal axis is limited as shown in Fig. 12, by a bolt )4- engaging a hole 95 and carrying a spacer 96, both bolt 94 and spacer 96 being received in an enlarged hole 97 formed in the side wall of the side arm 71.

An upwardly projecting latch dog 106 is pivotally carried between a pair of lugs 101 secured to the inner wall of the end gate '77. The upwardly projecting position of the latch dog 139 is defined by engagement between a surface 102, formed on its inner side, and a positioning boss 1&3 formed on a pattern plate 7ft. Thus, when a pattern plate 7G is not positioned within the pattern carrier framework, the latch 10!) is free to fall into a downwardly extending inoperative position (see Figs. 2 and 17), and can be left in this position, if desired, when a pattern plate is inserted in the carrier so that such carrier will cycle without forming a mold.

Construction or" the mold material container, generally indicated by the reference 110, may be understod from a comparison of the plan View thereof shown in Fig. 1 with the side elevation such as shown in Fig. 2. This 7 container is of sheet metal construction built around 'a pair of side frames 111 extending along either side of that portion of the container which will be referred to as its upper surface 112 or top. The container includes a pair of side Walls 113, a bottom wall 114 and inner and

outer end walls

115 and 116. A cleanout panel 117 is detachably secured to the bottom wall 114 alongthe inner end thereof An opening 118 is provided in the top wall 112, this opening being defined by a frame of interconnected tubing members 119 of rectangular cross section, and'a rectangular sealing plate 120 is secured to the outer surfaces of these members 119. The container construction includes an internal bafile 121 of mesh I material.

In over-all construction, the container may be considered to be composed of two sections, one, a material transfer section generally indicated in Fig. 2 by the reference 127 and the other, a storage section, generally indicated in this view by the reference 128. The volurne of the container comprising the material transfer section may be considered as that adjacent the rectangular opening 118. Referring to Fig. 4, where the container is shown with the opening 118 in a horizontal position, the material transfer section comprises that portion of the container located above the area of the opening. The remaining volume of the con tainer comprises the storage section. As will be more thoroughly appreciated when the operation of the machine is discussed in detail, this sectionalized construction of the container requires a lateral movement of material from the storage section to the discharge section in passing into or out of the opening 118.

I This container is mounted upon the pivot shaft 56'of the support assembly by a pair of brackets 122, each bracket being secured to one of the side frame members 111 of the container by bolts 123, and each bracket including a bearing hole 124 carrying a bushing 125. The pivot shaft 56 is provided with portions 126 which engage the bushings so that the entire container 110 is rotatably mounted thereon.

A toggle type latch assembly, generally indicated by the reference 130, is secured to the .outer end wall 116 of the container. Details of the. construction of this latch assembly are shown in Fig. 17 together with the manner in which this latch operates to engage the latch dog 100 carried by the end gate 77 of the pattern carrier. The

. principal parts of this assembly consists of a latch handle 131 and a latch 132 which is pivotally secured to the handle 131 by a pin 133. A U-shaped bracket having two sides 134 and a channel-shaped end section 135 carries a pivot pin 136 for mounting the latch handle 131 and a second pin .137 engaging a slot 138 formed in the latch 132. In Fig. 17, the parts are shown in full line in the unlatched position, latched position being indicated in phantom. Latching and unlatching movement of the latch handle 131 is controlled by the engagement of a roller type cam follower 139 carried by the latch handle with a pair of cam bars 140 carried by a stationary framework to be hereinafter described.

Figure 17 also discloses additional details of the construction and mounting of the latch dog 100, including the previously mentioned engagement between its surface 102 and the boss 103 of a pattern plate, the shape of the mounting lugs 101 in side elevation, and the fact that the latch dog 100 is carried by a pivot pin 104 whose ends are received in slotted holes formed in each of the lugs 101 and engaged by a pair of adjusting screws 105 so that the position of the pivot pin 104 can be changed rel.

ative to the end gate 77 of the pattern carrier, or more particularly, relative to the rectangular sealing flange 106 forming part of the construction of each pattern plate 70 and which is adapted to engage the sealing frame 120 of the container 110.

This sealing engagement between theflange of a pattern plate and the frame bordering the opening in the container takes place during the mold forming operation. Each molding unit, consisting ,of the support assembly, the pattern carrier and the container rotate with the turntable of the machine, and, except during that segment of their travel when the mold forming operation is performed, the pattern carrier and container occupy what may be termed'normal positions. These normal positions are shown in Figs. 2 and 7, which show the positions occupied by the pattern carrier and container while passing through the oven for the curing operation, and in Fig. 5, which shows these parts in the position they occupy during the ejecting or stripping operation. These views show that the normal position of the pattern carrier is one wherein its

side frame arms

71 and 72 extend outwardly from the center of rotation of the turntable in a substantially horizontal attitude, and in this position, the

meld forming surface 141 of the pattern plate (Fig. 2) is irected upwardly. The normal position of the con- 1 tainer is one where its end wall 115 rests against the bumper 34 carried by the plate 32 of the turntable,and its opening, bordered by the sealing frame 120, 'is directed upwardly and outwardly from the .center of the turntable.

Pattern plate assembly The pattern plate is an assembly consisting of a pattern As previously mentioned, the pattern plate 70 is bor- V dered' by a'sealing flange 106 (Fig. 10). Within this flange as a border, the plate is shaped to the pattern desired. The plate is provided with depending end and side Walls and which terminate in bosses 146 located adjacent eachcorner of the plate. A headed guide, pin 147 is slidably mounted in each 'of thesebosses, its headed end 148 being seated in a recess formed in the plate 713 so as to lie flush with the surface thereof. A stud 149 is formed on the opposite end of the guide pin 147 and serves to connect the pin to a knockout plate 150. Other bosses 151 depend from the surface of the plate 70 (Fig. 15) and are each drilled to slidably receive a knockout pin 152. Any number of these knockout pins may be used in a particular assembly, depending upon the nature of the pattern, each pin being conected to the knockout plate by a stud 153 and nut 154. This nut 154 together with a nut 155 which'engages the stud 149 of each guide pin 147 are seated in recesses formed in the lower surface 156 of the knockout plate.

During the ejecting operation the knockout plate is caused to be moved upwardly relative to the surface of the pattern plate 70, as shown in Fig. 6, and, to insure return movement to a normal position such as shown in Fig. 15, a number of return springs 157 are mounted around a numberof the knockout pins 152, these springs being positioned between the inner surface 158 of the knockout plate and the inner surface 159 of the boss 151.

Referring to Fig. 10, the inner end wall of the pattern plate is provided with a pair of locating bosses 160 which are adapted toregister against the end wall 73 of the pattern plate" carrier. Another locating boss 103 is formed on the outer end wall of the pattern plate, this 1 boss being adapted to register against the surface 102 on the latch dog 100. The side walls 145 of the pattern plate (Fig. 15) carry the flanges 85 which engage the pattern carrier slides 83.

Ejector This assembly A detail of the construction I porting frame and a roller table movable vertically relative thereto. The frame consists in a pair of side rails 165, connected at one end by a cross member 166, and each carrying a vertical panel 167 at the other end. Each of the panels 167 is reinforced by an upright member 168 of angle cross section and the two brackets 167 are interconnected by a transverse sheet metal end member 169. A pair of inner and outer upper arms 170 and inner and outer lower arms 171 are each pivotally secured to the uprights 168, with each pair of

arms

170 and 171 being interconnected by transversely extending channel members 172 and a plate 173. The arms are pivotally connected to inner and outer upright members 174, the upper arms 170 being pivotally secured to a cross shaft 175 and the lower arms to a cross shaft 176. The cross shafts are located so that a parallel relationship is defined between each pair of

arms

170 and 171.

Diagonal members 177 (Fig. interconnect the upright members 174, as do transverse angles 178. A horizontally extending platform 180 is connected to the upper ends of the uprights and braced by a pair of gusset plates 181. Two series of

rollers

182 and 183 are mounted in brackets 184 carried by the platform 18%], the rollers in each series having their rotational axes located substantially radially with reference to the center of rotation of the turntable of the machine, with each series being arranged arcuately with respect to the center of rotation of the turntable (see Fig. 1).

This mounting of the platform 180 allows it to move vertically in a horizontal position. Such vertical movement is obtained by a cam 185 carried by the inner upper arm 170, and the ejector is located with reference to the turntable in a position such that the lower or working surface 186 of the cam will be contacted by the roller cam follower 63 of the support assembly of each molding unit as such molding unit moves past the ejector. Normal or rest position of the ejector is defined by the engagement between an elevation controlling screw 18? and a cross member 188 extending between the side frame members 165.

The

rollers

182 and 183 contact a depending flange 189 formed along the edges of the knockout plate 150.

Oven construction The oven is rectangular in cross section and extends around more than half of the circumference of the turntable as can be seen from Fig. 1. Details of its construction are best shown in Figs. 2 and 7. It has an upper wall 190, an outer wall 191, a bottom wall 192, and an inner wall formed of two separate portions, an upper portion 193 and a lower portion 194, the adjacent ends of these

portions

193 and 194 being separated to form a continuous slot around the entire inner side wall of the oven. The bottom wall of the oven is supported on a series of horizontal beams 196, each resting on an inner leg 197 and being connected to an outer upright 198 which extends beyond the top wall of the oven. Each of the uprights 198 carries a cantilever beam 199 which supports the upper oven wall 190 and which is braced in position by a diagonal 2%.

A series of upper gas burners 291 and lower gas burners 202 extend throughout the length of the oven and a series of exhaust ducts 2133 communicate with the interior of the oven through the top wall 190 thereof, these ducts being connected by a manifold 204 to an exhaust stack, preferably equipped with a blower (not shown). This duct system is provided to insure combustion, to remove offensive odors accompanying the curing of the molding material, and to afford some control over the heat transfer from the oven to the working area surrounding the machine and particularly to the operating parts of the machine. Additional control over heat transfer is provided in the form of bafile plates of insulating material. These bafiie plates are indicated in Fig. and consist in one plate 266 connected to the inner end wall 73 of each pattern carrier by studs 297 and adjacent plates 2158 which are carried by and rotate with the turntable portion of the machine. These bafiie plates are positioned to substantially fill in the slot formed in the inner side wall of the oven and thus minimize the amount of heat that may escape through that opening.

Feeder mechanism This mechanism is carried by the oven structure and is shown in Fig. 7 and is provided to replenish the supply of the pulverant mold forming material carried within the container. An auger-type conveyor 21%) extends over the machine and terminates in a spout 211, the end of which overlies a discharge hopper 212 having a discharge spout 213. The hopper 212 is pivotally carried between a pair of brackets 214 carried by an oven supporting beam 192, and is positioned so that the spout 213 of the hopper closely overlies the opening 118 of each of the containers passing this station. In Fig. .7, the hopper 212 is shown in full line in a receiving position and in dotted line in a discharge position, and its pivotal movement between these positions is in response to the actuation of a fluid pressure cylinder 221 pivotally carried by a bracket 222 mounted upon a member 223 supported by the upper beam 199 of the oven. The free end of the rod 220 of the actuating cylinder 221 is pivotally secured to the hopper.

Operation of the fluid pressure cylinder 221 is controlled by a three-way valve assembly 225, shown in detail in Fig. 8. This assembly consists of a plate 226 mounted on one of the supporting legs 197 for the oven and carrying a pivoted lever 227 and either a suitable valve 228 or a solenoid, adapted to be actuated by a plunger 229. The lever 227 and valve assembly 225 is positioned so as to be contacted by the roller cam follower 63 of each molding unit. When this valve assembly is actuated by the passage of a molding unit, a resultant actuation of the fluid pressure cylinder 221 takes place, producing a movement of the hopper 212 to the discharge position indicated in dotted line. After the roller 63 moves out of contact with the lever 227, a spring 236 returns the lever to the dotted position, allowing the valve (which is of the spring loaded type) to return to its other position and returning the hopper to receiving position.

Cooling system This system is preferably included for controlling the temperature of certain critical parts of the machine. These parts are the bearings and gear segment of the molding unit assembly and the sealing frame of the container. Coolant is circulated to these parts through supply lines 231 and 232 (Fig. 2), line 231 being the inlet passage and line 232, the outlet. These lines are secured to a fitting 233, located on the rotational axis of the turntable, inlet line 231 being extended through the fitting 233 so that concentric passages are formed which are connected to the concentric passages of a commercial type of rotary joint 234. A cylindrical manifold, comprising an inlet section 235 and an outlet section 236 separated by a baflle 237, is mounted upon the upper hub plate 21 of the turntable, and the rotary joint 234 is connected to this manifold. The inner passage of the rotary joint connects with the inlet section 235 of the manifold, and the outer concentric passage of the joint is connected by a U-shaped line 243 to the outlet section of the manifold. The manifold and rotary joint 234 rotate with the turntable, while the supply lines 231 and 232, together with the fitting 233 are stationary.

A branch line 238 leads from the inlet manifold 235 to a. three-way swivel joint 239 secured to one end of the pivot shaft 56 of each molding unit (Fig. 10). The pivot shaft 56 is formed with a hollow center providing a passage 240 between its ends, and communicating with another three-way swivel joint 241 secured to the opposite end of the shaft. .A return line 242 leads from 1 11 this three-way swivel joint 241 to the return manifold 236. At the three-way .swivel joint 239 a portion of the coolant is diverted through a line 244 leading to a connection 245 on one side of the tubular frame member 119 of the container unit. A similar connection is provided at the opposite side of this tubular frame and a line 246 leads therefrom back to the swivel joint 241-at the other end of the pivot shaft 56. 7

Thus, coolant circulates through the shaft 56 to carry away heat transferred thereto through the side arms '1' 1 and 72 of the pattern carrier, and to the tubular members of the container unit to carry away heat transferred to the frame 12% thereof through contact with the pattern plate. The temperature control "of the frame 123 is desirable due to the fact that the outer surface of this frame must be kept perfectly clean so that it may be positioned in firm sealing engagement with the sealing flange1fi6 of the pattern plate. If the temperature of the frame 126 is not controlled it is likely to rise to a point where the thermo-setting resin in the mold forming material would adhere thereto and build up thereon; and, since the mold forming material is such a finely divided pulverant it is practically impossible to eliminate the presence of all material dust, which will settle over all parts of the machine and adhere thereto unless some means such as dust shields or temperature control is employed.

Operation of machine and control cams The means employed for moving the pattern carrier and container unit of each molding unit through a mold forming operation have not been described, it being felt that this description would be clearer if coupled with a description of the operation of the machine in general. The complete cycle of the machine, with respect to any individual molding unit, will include the operations of mold forming, curing, and ejecting or stripping.

Referring to Fig. 1, this cycle of operation begins at a point just beyond the section line 5-5, with the turntable rotating in a counterclockwise direction. At this point, a molding unit which has just passed over 'the ejector has had its mold removed from the pattern plate thereby, and is ready to pass through that portion of the cycle of the machine during which a new mold is formed. A brief-interval is provided between the end of the ejecting operation and the beginning of the next mold forming operation in order to allow the pattern plate to be cleaned and conditioned therefor if necessary. During this interval the'pattern carrier is still projecting outwardly from the centerof the machine in a horizontal position such as shown in Fig. 5.

The mold forming cycle begins at the position ofthebeam 250 shown in Fig. 1 just beyond the location of the section line 5-5 in the direction of rotation. This beam is located at subfioor level and extends radially inwardly toward the center of the machine beneath the track 31 and under the pedestal 26. Secured to this beam at a position radially outwardly from the circumference of the turntable is an upright stanchion 251 (Fig. 4). Two other similar beams 25!) each carrying similar stanchions 251 are arranged at radial intervals from the position of the beam first mentioned, and an end view of these three beams and. stanchions is shown in Fig. to. cross members, upper .252 and lower 253, are rigidly secured to each stanchion 251, each cross member carrying a pair of clamping screws 254 provided with lock nuts 255. a A mounting plate 255 is secured between each pair of

cross members

252 and 253 upon each stanchion 251 by the clamping screws provided for this purpose, and

upper and'lower cam track 'mernbers 257 and 258m spectively are secured to the mounting plates 256, the

lower cam track 258 being formed as a continuous membet and the upper cam track 257 being composed of two members having their adjacent ends each connected to the centerrnounting plate 256a. At intervals between the A pair of mounting plates, the cam track members are interconnected by C-shaped brackets 259. These cam tracks are spaced to receive the roller cam follower 63 on the support or pedestal assembly of each molding unit, and, referring to Fig. 16, travel of the roller cam follower 63 along the cam track is in the direction from left to right in this view.

As the roller 63 enters the cam track section, which extends'around and defines the mold forming section of the machine, it first contacts the lower cam track 258 and is forced upwardly of the pedestal unit thereby. This upward movement of the cam follower produces an upward movement of the rack bar 53 and a clockwise rotation of the gear segment 57 as the parts are viewed in melt upon coming in contact with the frame and would 7 Fig. 13. Rotation of the gear segment 57 is accompanied by rotation of the pivot shaft 56 and produces a clockwise pivotal movement of the pattern carrier from' the position shown in Fig. 5 ,to the position shown in Fig. 3, the section line for this latter View being taken immediately beyond the end of the upwardly inclined portion of the lower track member 258 at the-left hand side of Fig. 16. p

This movement superimposes the pattern carrier upon the container and, immediately prior to the completion of this movement the roller cam follower 139 of the toggle latch assembly 130 is moved to unlatched position through contact with the cam bar 140 and then moved to latched position after contact between the pattern car. rier and container has been established. In Fig. 3, this latching movement has just been completed and the carrier has been secured to the container with the sealing flange of its pattern plate in firm engagement with the frame 120 of the container.

The roller cam follower -63, which is now in contact with the upper cam bar 257, enters the downwardly in c'lined portion 270 thereof and is forced downwardly, producing a downward movement of the rack bar 58 and opposite rotation of thegear segment 57, shaft 56 and pattern carrier keyed thereto. This movement of the pattern carrier is accompanied by a free pivoting of the container unit about the shaft 56, and after pattern carrier and container pass through the vertical, their weight forces the cam follower 63 into contact with the lower cam track 258. The lower cam track 25$, along its portion 271 secured to the mounting plate 256a, extends below the level of its initial portion 272, and this results in a downward movement of pattern carrier and container to'a position where the pattern carrier moves downwardly past its normal horizontal position to the dotted line position indicated in Fig. 4a position produced by approximately 30 of rotation of the pivot shaft 56 past the normal or horizontal position of the pattern carrier. This movement is provided in order to insure that the mold forming material in the container will be.

evenly deposited over the entire surface of thepattern plate.

pedestals 280 positioned below the turntable and consists of a channel member having a pair of vertically extending flanges 281v spaced to receivethe roller cam follower 67 secured to the slide 64, and shaped to withdraw the slide from its interfering position with the rack bar 58, hold it in such withdrawn position, and then return the slide to normal position after therack bar has again been moved upwardly beyond the point of interference. v

Upward movement of the rack bar takes place as the cam follower 63 travels along the next upwardly in- In order for this movement to. take place, the slide 64 (Fig. 13) of the pedestal assembly of the mold-.

clined section 275 of the lower cam track 258 and is accompanied by pivotal movement of the shaft 56, pattern carrier and container until pattern carrier and container again reach a position corresponding to that shown in Fig. 3. After reaching this position, another latch bar similar to the latch bars 140 previously mentioned, is provided to operate the toggle latch assembly 130 to unlatched position, leaving the pattern carrier free to be returned to its normal position as the roller follower 63 travels along the remaining downwardly inclined portion of the cam track. This normal position, in which the pattern carrier arms extend horizontally outward from the turntable, is maintained during the remaining portion of the cycle of the machine.

The pattern plate supported by the pattern carrier is assumed to have entered the mold forming stage in a properly heated condition and this temperature of the pattern plate causes an even layer of mold forming material to adhere to all the surfaces thereof. All excess material is returned to the container, the baffle of mesh material 121 being provided to break up any lumps.

It is to be noted that the mold forming operation is accomplished with less than 180 of movement required in order to bring the mold material container from its normal position to a position Where it is superimposed over the upright pattern plate. At the same time, an extra 20 to 30 of rotation has been included to bring the container to a position below the horizontal for depositing mold forming material on the pattern plate. This extra degree of inverting movement compensates for the normal angle of repose of the material which would place the material at an approximate angle of 30 to 40 were the container merely moved to a horizontal position. In other words, the material container is moved below the horizontal in order to place the material level substantially parallel to the pattern plate surface and thus insure the application of an even coat to the pattern plate.

The reduction in pivotal movement of the parts is made possible largely through the design of the material container-the provision of the material storage section 128 thereof displaced laterally from the position of the material discharging section 127. When the material container is returned to its normal position after inverting movement, the excess material in the discharging section 127 is free to fall directly downwardly into the storage section 128.

After the mold forming operation has been completed a brief interval of travel of the molding unit is provided to permit the mold to be inspected and any necessary minor repairs to be accomplished before it enters the curing stage.

As the molding unit approaches the mouth 277 of the oven the

arms

71 and 82 of the pattern carrier enter the slot between the upper and

lower portion

193 and 194 of the oven inner wall, and the pattern plate 70 is positioned within the oven, while the remaining portion of the molding unit travels adjacent the outer surface of the oven inner Wall. Thus, only that portion of the pattern carrier framework immediately surrounding the pattern plate is subjected to the direct heat of the oven. The principal moving parts of the molding unit located along the hinge axis defined by the pivot shaft 56 remain outside the oven and are further separated from the heat thereof by the insulating panel 206 carried by each pattern carrier and the adjacent insulating panels 208 which extend between each two adjacent pattern carriers and are supported by the turntable framework. This separation of the principal moving parts from the oven heat, together with the coolant system provided for carrying away heat transferred to these moving parts by conduction, insures that their operation will not be adversely affected by the curing process.

During the travel of the molding unit through the curing stage, the supply of molding material in the con- 14 tainer is replenished through the operation of the feeder mechanism, as controlled by the passage of a molding unit by the feederstation. i

When the pattern carrier emerges from the oven, the curing of the mold has been accomplished, and the mold, while still in a heated condition, has been formed into a rigid unit which can absorb normal handling without likelihood of damage. This quality of the mold, when cured, permits the location of the ejector unit immediately adjacent the discharge end of the oven, and as a molding unit passes the ejector, the roller cam follower 63 of the molding unit contacts the cam surface 186 of the control cam 185 producing an upward movement of the ejector table and upward movement of the knockout plate 159 of the pattern assembly as this knockout plate travels along the two series of

rollers

182 and 183 on the ejector table 186. The accompanying movement of the guide pins 147 and knockout plungers 152 strips the mold from the pattern and the mold can then be removed from the pattern carrier either manually or by suitable mechanical equipment.

This completes the cycle of operation of the machine. The pattern plate, having just emerged from the oven, is in a properly heated condition to receive a new charge of material during the ensuing molding cycle.

Operation of the modified construction shown in Figs. 19 to 23 is similar, and since the modifications have to do solely with the manner of controlling the position and movement of the parts of the molding unit, these modifications will be outlined briefly at this point.

The pedestal or support assembly 50a for the molding unit in this construction is secured to the rim channel member 27 of the turntable in the same manner as previously described for the pedestal assembly 50. The assembly 50a, however,- does not include the rack and gear sector but merely supports a pivot shaft 56a and includes a stationary roller 282 in place of the roller 63. The pattern carrier is similar in construction to that previously described, its

arms

71a and 72a being keyed to the pivot shaft to stabilize the carrier frame. A depending arm 283, mounting a roller 284, is secured to the carrier frame, as is another roller 285 to the carrier end gate 77a. The container unit is identical to that previously described, and is pivoted on the shaft 56a.

In this construction the normal horizontal position of the pattern carrier is defined by the engagement of the roller 285, carried by the end gate thereof, with a circular supporting track 286 which extends around the entire circumference of the machine except for the mold forming segment thereof. Along the ejection segment of the circumference, the supporting track 286 is supplemented by a second supporting track carried above the track 286 on brackets 287, and the roller 285 extends between these two tracks to positively prevent any upward movement of the carrier during the ejecting operation.

At the end of the ejection segment, the roller 284, mounted on the crank arm 283 of the carrier, contacts a main cam bar 288 which takes over the function of supporting the carrier and defining its position. Fig. 21 shows the relationship of the parts at this time, with the roller 285 still in contact with the supporting track 236 and the roller 284 in contact with the initial portion of the cam bar 288. Cam bar 288 is shaped to produce pivotal movements of the carrier and container of the molding unit similar to those previously described. The first portion of this movement consists in rotating the carrier into juxtaposition with the container, as shown in Fig. 22, and during the last portion of this rotation a second cam bar 289 is employed to define the position of the carrier in a mannersimilar to the operation of the upper cam track shown in Fig. 16 and previously described. Similar cams are employed to operate the