US2391715A - Core box - Google Patents

Core box Download PDF

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US2391715A
US2391715A US463206A US46320642A US2391715A US 2391715 A US2391715 A US 2391715A US 463206 A US463206 A US 463206A US 46320642 A US46320642 A US 46320642A US 2391715 A US2391715 A US 2391715A
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core box
core
cores
box
walls
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Expired - Lifetime
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US463206A
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Elmer C Kloss
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National Malleable and Steel Castings Co
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National Malleable and Steel Castings Co
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Priority to US463206A priority Critical patent/US2391715A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22CFOUNDRY MOULDING
    • B22C7/00Patterns; Manufacture thereof so far as not provided for in other classes
    • B22C7/06Core boxes

Definitions

  • This invention relates to an improved core lbox for making cores used in the manufacture of cast anchor chain, mooring chain and the like.
  • the molds for the links are made of a plurality of baked sand cores.
  • the cores are made in sections so that precast links can be assembled in certain cavities in the cores.
  • the connecting links, whichjoin the precast links, are formed by pouring metal in the mold cavities provided therefor in the assembled core sections,
  • the method of assembling the various links and cores is described in my copending application Serial No. 451,882, filed July 22, 1942, now Patent No. 2,348,979, issued May 16, 1944.
  • the present invention deals with improved apparatus for making the cores used with the method described and claimed in the aforesaid application.
  • the core box is mounted on a molding machine having provisions for inverting the core box and withdrawing the cores on a plate with which they are transferred to a baking oven.
  • parts of the core box must move relative to the remainder thereof so as to permit the core to be withdrawn.
  • a feature of my invention therefore relates to the means for clamping and releasing the movable parts of the core box so that the molder may clamp and release the movable parts simply and expeditiously during the molding operation.
  • a further feature of the invention relates to the means for clamping the cover plate on the core box so that it may be readily released and lowered with the core when the core box is inverted before removing the core therefrom.
  • Figure 1 is a plan view of the core box.
  • Figure 2 is a view of the core box in front eleration.
  • Figure 3 is a plan view of a core.
  • Figure 4 is a side view of a core.
  • Figure 5 is an end view of a core.
  • Figure 6 is a view similar to Fig. 1 with the parts moved to the position for removing a core.
  • Figure 7 is a view in vertical section, taken on line 1-1 of Fig. 6.
  • Figure 8 is a view partly in vertical section, taken on line 8-8 of 1528.1-
  • Figure 9 is a partial sectional view, taken on line 9-9 of Fig. 2.
  • Figure 10 is a plan view of the core box mounted on a molding machine (only partly illustrated) showing the clamping means for the plate on which the cores are supported when removed from the core box;
  • Figure 11 is a view partly in vertical section and partly in front elevation of the mechanism shown inFig. 10.
  • the core box comprises a bottom wall I0 and side walls II.
  • Extending through openings in walls Il are rods I2 whichmovably support members I3 and I4 at the front and rear respectively of the core box.
  • the openings in side walls II are provided with bushings I5 which may be replaced when wear occurs.
  • the rear end of each of rods I2 is formed with a shoulder I6 against which member I4 abuts.
  • Nuts I'I prevent rods I2 from being withdrawn from member I4 so that the rods and member move as a unit relative to the remainder of the core box.
  • At the forward end of the rods arev handles I8 by which member I4 can be moved forwardly and rearwardly until stopped either by the rear surface I9 of walls II or by pegs 20.
  • Member I3 at the forward end of the core box is formed with openings for slidably receiving rods I2. Adjacent each of said openings is a key slot 2I adapted to receive a key 22 on each of the rods when the rods are rotated so that the keys are in registry with the key slots. At such times as keys 22 are in registry with key slots 2
  • a wall 30 which divides the core box into two compartments so that two sections of the core can be made in one box.
  • which forms a portion of the mold cavity for a connecting link.
  • Pattern 32 which is joined to pattern 3l forms one-halfof the pouring opening of the mold. .
  • Pattern 33 which forms a mold cavity for anpositioning the cores when they are assembled y prior to the pouring operation.
  • Figs. 3, 4 and 5 the various mold cavities can readily be distinguished the views of one of the cores made in the front compartment of the core box.
  • patterns 3l and 32 form cavities 44 and 45 respectively.
  • Pattern 34 forms cavity 46 and pattern 35 forms cavity 41.
  • Depression 42 in the core box forms projection 48 on the core and projection 46 forms depression 49.
  • Depression 4I in member I3 results in projection 56 on the core;
  • members I3 and I4 are rst clamped by keys 22 into engagement with the opposite ends of walls I I.
  • the core box is then filled with core sand of usual composition and the sand rammed well around the patterns.
  • the excess sand is next wiped oif ush with the top surface of the core box and a supporting plate placed on the top surface so as to completely cover the cores.
  • Members I3 and I4 are then released by turning handles I8 until keys 22 are in registry with keyslots 2l after which member I3Yis pulled forwardly by handles 24 and memberM is moved rearwardly by pushing on rods'IZ thus withdrawing patterns 34, 35 and 36, 31 from the cores. (See Fig. 6.)
  • the core box is mounted on a molding machine in such a manner that it can be inverted and the supporting plate lowered, thus withdrawing the cores from the core box.
  • the plate and cores can then be transferred to an oven where the cores are baked and ready for use.
  • the plate must be securely clamped thereto.
  • a particularly simple and effective means for clamping the plate to the core box is shown in Figs. 10 and l1. Only one side of the clamping device is illustrated, it being understood that the other side is the same, the mechanism being symmetrical about the center of the machine.
  • Supporting members on the molding machine provide bearings for trunnions 56 on a cradle 51.
  • the core box is secured to the cradle by machine screws 58.V
  • cradle 51 On each side of cradle 51 is a bearing member 59 and a bushing 69 for a shaft 6I which extends aboveY and' below the cradle.
  • the shaft has an enlarged portion 62 forming a shoulder 63 that rests on the upper surface of bushing to limit downward movement of the shaft.
  • a collar 64 surrounds a part of portion 62 to give additional support to the shaft.
  • a pin or setscrew 66 is a lever 61 having a tapered roller 68 pivotally mounted thereon.
  • a center post 69 upon which a lever 19 is pivotally mounted.
  • a turnbuckle 1I joins lever 16 with an arm 12 secured to the bottom of shaft 6 I,
  • a compression spring 13 is positioned between aim 12 and the bottom surface of bushing 69 so as to normally pull the shaft downwardlyuntil shoulder 63 is in engagement with the-upper-surface of bushing 60. It will be ob-
  • the upper end of each shaft isI served that the pivotal connection at 14 between turnbuckle 1I and lever 19 is spaced from the pivot point of said lever. Therefore as end 15 of lever 10 is moved to the left (as viewed in Figs.
  • Supporting plate 16 is formed of a flat bottom portion 18 and upstanding reinforcing ribs 19. At each end of the bottom portion is a sloping surface adapted to be engaged by the adjacent roller 68 as the latter is moved into clamping position.
  • Roller 68 is located vertically on shaft 6I so that in clamping position spring 13 is slightly compressed as is indicated by the position of shoulder 63 which is shown in Fig. 11 raised in relation to the upper surface of bushing 66. level ⁇ 61 is rotated to released position spring 13 pulls shaft 6I, and hence lever 61, downwardly until shoulder 63 engages the upper surface of bushing 69.
  • the outermost part of roller 68 is slightly above the lower end of sloping surface 86.
  • the molder may perform all of the operationsfrom one side ofthe molding machine since members I3 and I4 and lever I5 are all operable from the front of the core box.
  • the operations may be performed rapidly and effectively by one molder with no loss of time in clamping, releasing and moving the various parts.
  • a core box comprising bottom and side walls, a movable member extending through each side wall, front and rear Walls mounted on said members, said rear wall being'secure'd to said members for movement therewith, said front wall being slidable on said members for movement forwardly and rearwardly of said box, and wedging means on said members and front wall for forcing said front and rear walls into engagement with the ends of said side walls.
  • a core box comprising bottom and side walls, movable means extending through said side walls, a rear wall mounted on said movable means for movement-therewith forwardly and rearwardly of said core box, a front wall slidably mounted on said movable means for independent movement forwardly and rearwardly of said core box, and wedging means on said front wall and said movable means for wedging said front and rear Walls into engagement with the ends of said side walls.
  • a core box comprising bottom and side walls, movable means extending through said side walls, a rear wall mounted on said movable means for movement therewith forwardly and rearwardly of said core box, a front wall slidably mounted on said movable means for independent movement forwardly and rearwardly of said core box, a pair of keyvvays in said front wall and a pair of keys on said movable means adapted, in one position of said movable means, to permit forward and rearward movement of said front and rear walls and in another position to wedge said front and rear Walls into engagement with the ends of said sidewalls.
  • a core box for making chain comprising a bottom wall having patterns for portions of a pair of connecting links secured thereto, side Walls, movable front and rear walls having patterns for portions of precast links secured thereto, and means for controlling movement of said rear wall from the front of said core box comprising a pair of members extending through said front, side and rear walls and adapted to move lwith said rear wall relative to said fro-nt and side walls.
  • a core box for making chain comprising a bottom Wall having patterns for portions of a pair of connecting links secured thereto, side walls, movable front and rear walls having patterns for portions of precast links secured thereto, means for controlling movement of said rear Wall from the front of said core box comprising a pair of members extending through said front, side and rear Walls and adapted to move with said rear wall relative to said front and side Walls, and means on said controlling means adapted to engage said front wall to wedge said front and rear walls into engagement with said side Walls.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)

Description

E. C. KLOSS com: Box
Filed' oct. 24, 1942 3 Sheets-Sheet l INVENfoR [limer Kar.: Bamf ATTORNEY E. c. KLoss Dec. 25, 1945.
CORE BOX 3 Sheets-Sheet 2 Filed 0G11. 24, 1942 INVENTOR B 707er 6. /f/ass UML/0. @ML
ATTORNEY Dec. 25, 1945. E. c, KLOSS 2,391,715
CORE' Box Filed Oct. 24, 1942 3 Sheets-Sheet 3 INVENTOR [//wcr /n//ass Namibi. CMP
ATTORNEY Patented Dec. 25, 1945 UNITED STATES PATENT OFFICE CORE BOX Application October 24, 1942, Serial No. 463,206
Claims.
This invention relates to an improved core lbox for making cores used in the manufacture of cast anchor chain, mooring chain and the like.
In the manufacture of cast chain the molds for the links are made of a plurality of baked sand cores. The cores are made in sections so that precast links can be assembled in certain cavities in the cores. The connecting links, whichjoin the precast links, are formed by pouring metal in the mold cavities provided therefor in the assembled core sections, The method of assembling the various links and cores `is described in my copending application Serial No. 451,882, filed July 22, 1942, now Patent No. 2,348,979, issued May 16, 1944. The present invention deals with improved apparatus for making the cores used with the method described and claimed in the aforesaid application.
In making the cores the core box is mounted on a molding machine having provisions for inverting the core box and withdrawing the cores on a plate with which they are transferred to a baking oven. Inasmuch as impressions for several links are formed in each core, one of the impressions being at right angles to the others, parts of the core box must move relative to the remainder thereof so as to permit the core to be withdrawn. A feature of my invention therefore relates to the means for clamping and releasing the movable parts of the core box so that the molder may clamp and release the movable parts simply and expeditiously during the molding operation.
A further feature of the invention relates to the means for clamping the cover plate on the core box so that it may be readily released and lowered with the core when the core box is inverted before removing the core therefrom.
Other features and advantages of the invention will, be understood from the following description taken in conjunction with the drawings, in which:
Figure 1 is a plan view of the core box.
Figure 2 is a view of the core box in front eleration.
Figure 3 is a plan view of a core.
Figure 4 is a side view of a core.
Figure 5 is an end view of a core.
Figure 6 is a view similar to Fig. 1 with the parts moved to the position for removing a core.
Figure 7 is a view in vertical section, taken on line 1-1 of Fig. 6.
Figure 8 is a view partly in vertical section, taken on line 8-8 of 1528.1-
Figure 9 is a partial sectional view, taken on line 9-9 of Fig. 2.
Figure 10 is a plan view of the core box mounted on a molding machine (only partly illustrated) showing the clamping means for the plate on which the cores are supported when removed from the core box; and
Figure 11 is a view partly in vertical section and partly in front elevation of the mechanism shown inFig. 10.
Referring to the drawings, the core box comprises a bottom wall I0 and side walls II. Extending through openings in walls Il are rods I2 whichmovably support members I3 and I4 at the front and rear respectively of the core box. The openings in side walls II are provided with bushings I5 which may be replaced when wear occurs. The rear end of each of rods I2 is formed with a shoulder I6 against which member I4 abuts. Nuts I'I prevent rods I2 from being withdrawn from member I4 so that the rods and member move as a unit relative to the remainder of the core box. At the forward end of the rods arev handles I8 by which member I4 can be moved forwardly and rearwardly until stopped either by the rear surface I9 of walls II or by pegs 20.
Member I3 at the forward end of the core box is formed with openings for slidably receiving rods I2. Adjacent each of said openings is a key slot 2I adapted to receive a key 22 on each of the rods when the rods are rotated so that the keys are in registry with the key slots. At such times as keys 22 are in registry with key slots 2|, member I3 may be moved forwardly on rods I2 until stopped by pegs 23. Handles 24 on member I3 are provided to slide the member as desired. Immediately adjacent each key slot 2| is a sloping surface 25 adapted to be engaged by the inner end 26 of the key as rods I2 are rotated. The wedging action caused by the engagement of ends 26 with surfaces 25 will draw members I3 and I4 tight against the forward and rear ends respectively of walls l I.
Extending across the middle of the core box is a wall 30 which divides the core box into two compartments so that two sections of the core can be made in one box. In the front compartment is pattern 3| which forms a portion of the mold cavity for a connecting link. Pattern 32 which is joined to pattern 3l forms one-halfof the pouring opening of the mold. .These patterns are secured to the bottom of the core box and a pair of cores made therefrom forms the upper half of the mold. In the rear compartment is pattern 33 which forms a mold cavity for anpositioning the cores when they are assembled y prior to the pouring operation.
In Figs. 3, 4 and 5 the various mold cavities can readily be distinguished the views of one of the cores made in the front compartment of the core box. Thus patterns 3l and 32 form cavities 44 and 45 respectively. Pattern 34 forms cavity 46 and pattern 35 forms cavity 41. Depression 42 in the core box forms projection 48 on the core and projection 46 forms depression 49. Depression 4I in member I3 results in projection 56 on the core;
In the process of moldingthe cores members I3 and I4 are rst clamped by keys 22 into engagement with the opposite ends of walls I I. The core box is then filled with core sand of usual composition and the sand rammed well around the patterns. The excess sand is next wiped oif ush with the top surface of the core box and a supporting plate placed on the top surface so as to completely cover the cores. Members I3 and I4 are then released by turning handles I8 until keys 22 are in registry with keyslots 2l after which member I3Yis pulled forwardly by handles 24 and memberM is moved rearwardly by pushing on rods'IZ thus withdrawing patterns 34, 35 and 36, 31 from the cores. (See Fig. 6.)
The core box is mounted on a molding machine in such a manner that it can be inverted and the supporting plate lowered, thus withdrawing the cores from the core box. The plate and cores can then be transferred to an oven where the cores are baked and ready for use. However, before the core box is inverted the plate must be securely clamped thereto. A particularly simple and effective means for clamping the plate to the core box is shown in Figs. 10 and l1. Only one side of the clamping device is illustrated, it being understood that the other side is the same, the mechanism being symmetrical about the center of the machine. Supporting members on the molding machine provide bearings for trunnions 56 on a cradle 51. The core box is secured to the cradle by machine screws 58.V On each side of cradle 51 is a bearing member 59 and a bushing 69 for a shaft 6I which extends aboveY and' below the cradle. The shaft has an enlarged portion 62 forming a shoulder 63 that rests on the upper surface of bushing to limit downward movement of the shaft. A collar 64 surrounds a part of portion 62 to give additional support to the shaft. square and secured thereto by a pin or setscrew 66 is a lever 61 having a tapered roller 68 pivotally mounted thereon.
Extending downwardly from the under side of cradle 51 is a center post 69 upon which a lever 19 is pivotally mounted. A turnbuckle 1I joins lever 16 with an arm 12 secured to the bottom of shaft 6 I, A compression spring 13 is positioned between aim 12 and the bottom surface of bushing 69 so as to normally pull the shaft downwardlyuntil shoulder 63 is in engagement with the-upper-surface of bushing 60. It will be ob- The upper end of each shaft isI served that the pivotal connection at 14 between turnbuckle 1I and lever 19 is spaced from the pivot point of said lever. Therefore as end 15 of lever 10 is moved to the left (as viewed in Figs. 10 and 11), arm 12, and hence shaft 6I, will be rotated in a counter-clockwise direction, Fig. 10, and roller 68 will be moved out of engagement with supporting plate 16 which covers the top of the core box. The released position of roller 6B is shown in dot-dash lines in Fig. 10 and to avoid confusion the position of turnbuckle 1I in released position is illustrated by a dot-dash center line 11.
Supporting plate 16 is formed of a flat bottom portion 18 and upstanding reinforcing ribs 19. At each end of the bottom portion is a sloping surface adapted to be engaged by the adjacent roller 68 as the latter is moved into clamping position. Roller 68 is located vertically on shaft 6I so that in clamping position spring 13 is slightly compressed as is indicated by the position of shoulder 63 which is shown in Fig. 11 raised in relation to the upper surface of bushing 66. level` 61 is rotated to released position spring 13 pulls shaft 6I, and hence lever 61, downwardly until shoulder 63 engages the upper surface of bushing 69. However, when in released position the outermost part of roller 68 is slightly above the lower end of sloping surface 86. Hence, when the roller is moved to clamping position it will roll up surface 89 and raise shaft 6I against the pressure of spring 13. Plate 16 is thus securely held in contact with the core box. The core box may then be inverted in the molding machine and supporting plate 16 released by moving handle 8l at the other end of lever 10 to the position corresponding to that shown in dot-dash lines in Fig. 19. The usual platform of the molding machine (not shown) on which plate 16 rests may then be lowered which results in the cores being withdrawn from the core box. The inner surfaces 82 of walls II and surfaces 83 of wall 30 are formed with the usual amount of pattern draft so that the cores will readily slip out of the core box.
It will be observed that in making cores with my improved core box the molder may perform all of the operationsfrom one side ofthe molding machine since members I3 and I4 and lever I5 are all operable from the front of the core box. Thus the operations may be performed rapidly and effectively by one molder with no loss of time in clamping, releasing and moving the various parts.
The terms and expressions which I have em? ployed are used as terms of description and not of limitation, and I have no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof, but recognize that various modifications are possible within the scope of the invention claimed.
What I claim is:
1. A core box comprising bottom and side walls, a movable member extending through each side wall, front and rear Walls mounted on said members, said rear wall being'secure'd to said members for movement therewith, said front wall being slidable on said members for movement forwardly and rearwardly of said box, and wedging means on said members and front wall for forcing said front and rear walls into engagement with the ends of said side walls.
2. A core box comprising bottom and side walls, movable means extending through said side walls, a rear wall mounted on said movable means for movement-therewith forwardly and rearwardly of said core box, a front wall slidably mounted on said movable means for independent movement forwardly and rearwardly of said core box, and wedging means on said front wall and said movable means for wedging said front and rear Walls into engagement with the ends of said side walls. f
3. A core box comprising bottom and side walls, movable means extending through said side walls, a rear wall mounted on said movable means for movement therewith forwardly and rearwardly of said core box, a front wall slidably mounted on said movable means for independent movement forwardly and rearwardly of said core box, a pair of keyvvays in said front wall and a pair of keys on said movable means adapted, in one position of said movable means, to permit forward and rearward movement of said front and rear walls and in another position to wedge said front and rear Walls into engagement with the ends of said sidewalls. Y
4. A core box for making chain comprising a bottom wall having patterns for portions of a pair of connecting links secured thereto, side Walls, movable front and rear walls having patterns for portions of precast links secured thereto, and means for controlling movement of said rear wall from the front of said core box comprising a pair of members extending through said front, side and rear walls and adapted to move lwith said rear wall relative to said fro-nt and side walls.
5. A core box for making chain comprising a bottom Wall having patterns for portions of a pair of connecting links secured thereto, side walls, movable front and rear walls having patterns for portions of precast links secured thereto, means for controlling movement of said rear Wall from the front of said core box comprising a pair of members extending through said front, side and rear Walls and adapted to move with said rear wall relative to said front and side Walls, and means on said controlling means adapted to engage said front wall to wedge said front and rear walls into engagement with said side Walls.
ELMER C. KLOSS.
US463206A 1942-10-24 1942-10-24 Core box Expired - Lifetime US2391715A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2572452A (en) * 1949-02-23 1951-10-23 Eerro Engineering Company Sectional tapered bottom ring for hot tops
US2716789A (en) * 1951-09-21 1955-09-06 Walworth Co Foundry core forming apparatus
US2741817A (en) * 1950-08-03 1956-04-17 Universal Castings Corp Heat disposable pattern for molding a blade cavity
US3089205A (en) * 1960-06-23 1963-05-14 Osborn Mfg Co Mold and core blowing machine

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2572452A (en) * 1949-02-23 1951-10-23 Eerro Engineering Company Sectional tapered bottom ring for hot tops
US2741817A (en) * 1950-08-03 1956-04-17 Universal Castings Corp Heat disposable pattern for molding a blade cavity
US2716789A (en) * 1951-09-21 1955-09-06 Walworth Co Foundry core forming apparatus
US3089205A (en) * 1960-06-23 1963-05-14 Osborn Mfg Co Mold and core blowing machine

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