US2698976A - Machine for making molds - Google Patents
Machine for making molds Download PDFInfo
- Publication number
- US2698976A US2698976A US207106A US20710651A US2698976A US 2698976 A US2698976 A US 2698976A US 207106 A US207106 A US 207106A US 20710651 A US20710651 A US 20710651A US 2698976 A US2698976 A US 2698976A
- Authority
- US
- United States
- Prior art keywords
- obtruder
- sand
- mold
- flask
- molding
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C15/00—Moulding machines characterised by the compacting mechanism; Accessories therefor
- B22C15/10—Compacting by jarring devices only
- B22C15/12—Compacting by jarring devices only involving mechanical gearings
Definitions
- This invention relates generally to machines for making molds and more particularly to machines for packing sand in a flask and around the pattern or patterns therein to form a mold having packed sand or other molding agent of uniform texture and hardness.
- Molding machines made in accordance with the teachings of the prior art, and with which I am familiar, pack sand in a flask with a piston. These pistons are usually retarded by the hard packed areas of the sand usually formed at the point of pouring from an overhead hopper with the result that sand in the mold box or flask is not packed uniformly and it is not firm. These molds produce scaly castings because of the non-uniformity of the packed sand. Some of the sand in these prior molds is packed too hard thereby causing a blow. Prior machines have only been practical for use in making comparatively small molds on bench machines.
- an object of my invention to provide a machine for forming a mold which overcomes the above and other defects in-present day mold making machines and it is more particularly an object of my invention to provide a machine for making molds which is simple in construction, economical in cost, economical in manufacture, and efficient in operation.
- Another object of my invention is to provide a machine for making a mold which has a folding flexible obtruder for packing sand around the patterns in a mold box and means for inflating the obtruder to force sand into and around the patterns in a mold box and further means for deflating the obtruder and drawing it upwardly out of the way of the flask or mold box.
- Another object of my invention is to provide an elastic obtruder in which a minimum of tension is placed on the fastened marginal portions thereof upon the inflation thereof to pack sand in a mold box.
- Another object of my invention is to provide a folding elastic flexible obtruder for packing sand into a mold box which packs the sand or molding agent so that the mold has an even and uniform texture of sand or molding agent.
- Another object of my invention is to provide a molding machine having a novel combination and arrangement of arts.
- Fig. l is a vertical sectional view of my novel molding machine with parts thereof broken away for better illustration thereof, the obtruding member being in an operative position to pack sand in the mold box;
- Fig. 2 is a vertical sectional view with parts thereof broken away of my novel molding machine with the obtruding member drawn against the underside of the upper frame;
- Fig. 3 is a view taken on the line 3-3 of Fig. 4;
- Fig. 4 is an end elevational view of my machine shown in Figs. 1 and 2;
- FIG. 5 is a vertical sectional view of a modified form of my novel molding machine.
- Fig. 6 is a vertical sectional view of a modified form of head for my novel molding machine.
- FIG. 1 to 4 inclusive an inverted U-shaped frame 1' having parallel legs 2 and 2a and a transverse top frame member 3.
- a cylinder 4 having a central bore 4a is disposed centrally of the legs 2 and 2a and it has outwardly extending brackets 50 secured to the legs 2 and 2a by screw bolts 6.
- the cylinder 4 has an inlet aperture 7 in the bottom thereof connected by a pipe line 8 to a valve 9.
- valve 9 is connected by a pipe 11) to a source of air (not shown), the air being selectively fed to the cylinder 4 through the valve 9, pipe 8, and aperture 7 by the selective operation of the handle 12.
- a piston 13 with ring 11 moves in the cylinder 4 and it has a table or platform 14 mounted on the upper end thereof.
- the table 14 supports a mold plate 15 having upwardly extending pointed guiding pins 16 for engagement by the apertures 17 in the lower flange 18 of the flask 19.
- a half pattern 20 is disposed on the mold plate 15 and sand is placed in the flask 19 by an overhead hopper or by any other suitable means.
- An arcuate shaped chamber 25 is formed in the cross frame member 1 between an arched top 26 and an arcuate shaped inner portion 27 having radially extending, circumferentially spaced apertures 28.
- the chamber 25 has an inlet aperture 29 connected by a pipe line 30 to a valve 3a.
- the valve 3a comprises a casing 5 having a rotatable valve member 31 with a transverse aperture 32 therein.
- a pipe line 33 connected to the valve 3a leads to a source of air for selectively obtaining and providing a source of air for inflating a folding obtruder 34 by operation of handle 35 on shaft 32a.
- An outlet 36 from chamber 25, said outlet having a flange 21, is connected to a suction pump 37 in casing 41 having an outlet 59 through a valve 33 in casing 42 controlled by a handle 39.
- the casing 41 is secured to casing 42 by screw bolts 23.
- the casing 42 is secured to the flange 21 by screw bolts 24.
- the suction pump 37 also has an inlet pipe 46 which is open to the atmosphere.
- An inverted seat 40 is formed on the underside of the top frame member 3 and the marginal edge 43 of the obtruder 34 is secured thereto by an inverted L-shaped clamping member 44 and screw bolts 45.
- the clamping member 44 has an outer depending marginal flange 49 to engage the lateral outer side of the upper flange 43 on the flask 19 and it has an inner depending flange 47 for sealingly engaging the upper surface of the flask 19.
- the obtruder 34 is mounted so that folds 52 are formed intermediate thereof. By providing these folds, there is practically no lateral tension of the marginal edges 43 of the obtruder 34, thereby preventing the pulling out and unfastening of the marginal edges 43 of the obtruder 34 and consequent leakage of air and the blowing outwardly of sand. At no time is there any lateral pulling on the marginal edges 43 of the obtruder 34.
- the mold plate 15 and flask 19 with a pattern 20 are seated on the table 14 as shown in Fig. 1.
- the valve 3a controlling the source of air to the arcuate chamber 25 is shut off and the valve 38 is actuated to permit the suction pump 37, which operates continuously, to evacuate air from the chamber 25 and the chamber above the obtruder 34, thereby causing the obtruder 34 to move upwardly adjacent the inner side of the arcuate member 27 as shown in Fig. 2 out of the way of the flask 19.
- the flask 19 is filled with sand 22 by an overhead hopper or any other suitable method and the table 14 is moved upwardly by actuation of the valve 9 which provides a source of air in the cylinder 4 through the pipe 10, valve 9, pipe 8, and aperture 7 in the cylinder 4.
- the upper side 48 of the flask 19 sealingly engages the inner depending flange 47 of the clamping member 44 and the outer side of the upper flanged portion 48 of the flask 19 sealingly engages the depending flange 49 of the clamping member 44.
- valve 38 is then actuated to shut off the line leading to the suction pump 37 and the valve 3a is actuated to provide a source of compressed air through the pipe 33, aperture 32, pipe 30, and aperture 29 to the chamber 25, thereby causing the inflation of the obtruder 34 to pack the sand in the flask 19 around the pattern therein.
- the obtruder 34 will pack the sand uniformly in all parts of the mold inasmuch as if there is a greater resistance to any portion of the obtruder, it will not move as far into the packed sand as where there is no resistance, such as around the edges of the flask 19.
- valve 3a is shut off and the valve 38 is again actuated to draw the obtruder 34 upwardly into engagement with the member 28 as shown in Fig. 2 and out of the way of the flask 19.
- the valve 9 is then actuated to bring down the flask away from the clamping member 44 whereupon it is removed and another flask is placed thereon and the process is repeated.
- top frame member '70 has an arched top 71 and an arcuate shaped, apertured inner member 76 forming an arcuate shaped chamber 73.
- Longitudinally extending side chambers 74 and 75 are disposed on opposite sides of the chamber 73.
- the top 71 has an aperture 77 for engagement with the flanged end 78 of a pipe line 79.
- the flanged upper ends 86 and 87 of the longitudinally extending recessed chambers 74 and 75 are fluidly connected to flanged connections 84 and 85 on the pipe 79 by screw bolts 88 and 89.
- Arcuate shaped apertured walls 82 and 81 having apertures 80 and 83 are disposed transversely of the chambers 74 and 75.
- a flexible folding obtruder 91 is connected to an inverted seat 92 by clamping member 93 and screw bolts 94 and the outer marginal edges of the obtruder 91 are connected by a clamping member 95 to a flanged seat 96.
- the clamping member 95 has a depending portion 97 for sealingly engaging the side face of the upper flange of a flask 98. The operation of this form of my device is the same as that for the one shown in Figs.
- Fig. 6 is another modified head for my novel molding machine in which a top frame member 100 has a wall 101 with apertures 102 leading to the upper side of an obtruder 103 of the accordion type, the obtruder 103 having the marginal edges 104 thereof secured to the underside of flange 105 by a clamping member 106 secured by screw bolts 107.
- the obtruder 103 is inflated and drawn from the mold box 108 in the same manner as has been heretofore described by providing a source of air for the chamber 110 and also means for evaucating the air therefrom through port 109.
- a molding machine comprising a support for a mold box, a mold box on. said support, a head having a wall forming an open cavity, said head being spaced from said support with said mold box disposed therebetween, a flexible obtruder secured to said head forming a closed chamber in said head cavity and movable therein prior to molding, said mold box being adapted to contain molding material, and means to supply compressed air to said chamber to exert a pressure on said obtruder to move said obtruder into engagement with said molding material to compress said molding material into molded condition, the area of said obtruder supported across said cavity being considerably greater than the cross sectional area of said mold box, the surface area of said obtruder adapted to engage the molding material exceeding that necessary to conform to the engaged surface of said molding material when said molding material is in compressed condition whereby substantially no tension results in said obtruder when in the compressed molding position.
- a molding machine comprising a support for a mold box placed thereon, a head having a wall forming an open cavity of considerable extent and spaced from said support, a flexible obtruder secured to said head forming a closed chamber in said head cavity and movable therein prior to molding, means for effecting relative movement between said head and said support to cause engagement of said head with said mold box placed on said support, said mold box being adapted to contain molding material, and means for supplying compressed air to said chamber to exert pressure on said obtruder to move said obtruder into engagement with said molding material to compress said material into molded condition, the surface area of said obtruder adapted to engage the molding material exceeding that necessary to conform to the engaged surface of said molding material when said molding material is in compressed condition whereby substantially no tension results in said obtruder when in the compressed molding position, the surface area of said obtruder being substantially equal to the inside area of said cavity.
- a molding machine comprising a support for a mold box placed thereon, a head having a wall forming an open cavity of considerable extent and spaced from said support, a flexible obtruder secured to said head forming a closed chamber in said head cavity and movable therein prior'to molding, means for effecting relative movement between said head and said support to cause engagement of said head with said mold box placed on said support, said mold box being adapted to contain molding material, means for supplying compressed air to said chamber to exert pressure on said obtruder forcing said obtruder into engagement with said molding material compressing said material into molded condition, and suction means connected to said chamber for drawing said obtruder upward into said cavity prior to the application of pressure thereto, the surface area of said obtruder adapted to engage the molding material exceeding that necessary to conform to the engaged surface of said molding material when said molding material is in compressed condition whereby substantially no tension results in said obtruder when in the compressed molding position, the surface area of said obtruder being substantially equal to the inside
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Casting Devices For Molds (AREA)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US207106A US2698976A (en) | 1951-01-22 | 1951-01-22 | Machine for making molds |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US207106A US2698976A (en) | 1951-01-22 | 1951-01-22 | Machine for making molds |
US340315XA | 1954-09-16 | 1954-09-16 |
Publications (1)
Publication Number | Publication Date |
---|---|
US2698976A true US2698976A (en) | 1955-01-11 |
Family
ID=21873870
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US207106A Expired - Lifetime US2698976A (en) | 1951-01-22 | 1951-01-22 | Machine for making molds |
US280223A Expired - Lifetime US2715758A (en) | 1952-04-03 | 1952-04-03 | Machine for packing sand in a mold box |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US280223A Expired - Lifetime US2715758A (en) | 1952-04-03 | 1952-04-03 | Machine for packing sand in a mold box |
Country Status (6)
Country | Link |
---|---|
US (2) | US2698976A (fr) |
BE (2) | BE527884A (fr) |
CH (2) | CH328509A (fr) |
DE (1) | DE1162973B (fr) |
FR (2) | FR1099258A (fr) |
GB (3) | GB750979A (fr) |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2767446A (en) * | 1955-09-12 | 1956-10-23 | Kelsey Hayes Wheel Co | Molding machine |
US2805455A (en) * | 1957-09-10 | whitesell | ||
US2835004A (en) * | 1955-08-29 | 1958-05-20 | Crane Co | Bulb guide on molding diaphragm |
US2847736A (en) * | 1954-12-31 | 1958-08-19 | Pulvermacher Dietrich | Device for making sand molds for metal casting |
US2847735A (en) * | 1958-08-19 | butler | ||
US2852820A (en) * | 1955-03-14 | 1958-09-23 | Taccone Pneumatic Foundry Equi | Molding machine with roller strike off |
US2854712A (en) * | 1958-10-07 | Molding machine | ||
US2864136A (en) * | 1955-09-19 | 1958-12-16 | Taccone Pneumatic Foundry Equi | Combination lateral and vertical pressure diaphragm molding machine |
US2903762A (en) * | 1957-09-18 | 1959-09-15 | Donald C Caudron | Method and apparatus for forming cores |
US2962775A (en) * | 1960-12-06 | rekart | ||
US2968846A (en) * | 1958-03-05 | 1961-01-24 | Osborn Mfg Co | Foundry molding machine |
US2973562A (en) * | 1958-08-04 | 1961-03-07 | Osborn Mfg Co | Mold blowing and squeeze machine |
US3089206A (en) * | 1958-01-13 | 1963-05-14 | Osborn Mfg Co | Blow and squeeze molding machine and method of molding |
DE1166420B (de) * | 1958-05-19 | 1964-03-26 | Russell William Taccone | Membran-Pressformmaschine zur Herstellung von Giessereiformen |
US3168764A (en) * | 1958-07-09 | 1965-02-09 | Osborn Mfg Co | Foundry molding machine and method of molding |
DE1225821B (de) * | 1959-04-09 | 1966-09-29 | Osborn Mfg Co | Sandblasmaschine mit Membranpressvorrichtung zur Herstellung von Formen fuer Giessereizwecke |
US3289256A (en) * | 1966-12-06 | Mold compacting apparatus | ||
US3318629A (en) * | 1965-04-09 | 1967-05-09 | Jr Richard W Brandt | Tree-clamping jaws with deformable pads containing granular material |
US3890830A (en) * | 1972-12-13 | 1975-06-24 | Gerhard J Dyck | Grain moisture tester |
US4452056A (en) * | 1983-04-27 | 1984-06-05 | Pellerin Milnor Corporation | Liquid extracting apparatus |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2859499A (en) * | 1958-11-11 | Molding press head control system | ||
US2882566A (en) * | 1959-04-21 | redhead | ||
US2822592A (en) * | 1954-02-24 | 1958-02-11 | Douglas C Wendt | Method for making investment molds and castings |
US2830339A (en) * | 1955-11-25 | 1958-04-15 | Taccone Pneumatic Foundry Equi | Molding machine |
US2843893A (en) * | 1957-03-05 | 1958-07-22 | Budd Co | Apparatus and method for gating with diaphragm packing machines |
US2948029A (en) * | 1957-07-29 | 1960-08-09 | Kelsey Hayes Co | Safety control for molding machines |
BE634361A (fr) * | 1962-07-02 | |||
US3557867A (en) * | 1969-06-04 | 1971-01-26 | Gruenzweig & Hartmann | Casting apparatus |
NO179604C (no) * | 1994-01-19 | 1996-11-13 | Tore Sundquist | Oljeabsorberende artikkel som omfatter furubark |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US318784A (en) * | 1885-05-26 | Matthew e | ||
US331208A (en) * | 1885-11-24 | Matthew b | ||
US408386A (en) * | 1889-08-06 | Sand molding machine | ||
DE323380C (de) * | 1913-07-01 | 1920-07-21 | Hugh Victor Mac Kay | Formmaschine mit einem von einem Rande umgebenen elastischen Kissen |
US1352295A (en) * | 1920-09-07 | Molding-machine | ||
US2335560A (en) * | 1940-11-26 | 1943-11-30 | Morton Brayton | Laundry apparatus |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US302349A (en) * | 1884-07-22 | Matthew b | ||
DE168647C (fr) * | ||||
CH64976A (de) * | 1913-07-03 | 1914-08-01 | Johann Fuelscher | Formmaschine |
DE648293C (de) * | 1933-10-07 | 1937-07-28 | Wilhelm Ihmig | Waeschepresse |
DE742795C (de) * | 1939-02-10 | 1943-12-11 | Karl Glemser Fa | Von Hand betriebene Kolbenpresse fuer Waesche |
US2336428A (en) * | 1940-12-11 | 1943-12-07 | Huebsch Mfg Company | Clothes drier |
DE864141C (de) * | 1944-02-05 | 1953-01-22 | Zimmermann Maschf Gustav | Press- und Ruettelformmaschine |
DE801574C (de) * | 1949-04-17 | 1951-01-11 | Johannes Wisser | Verfahren und Vorrichtung zum gleichmaessigen Verdichten des Sandes in Pressformmaschinen |
US2654901A (en) * | 1950-01-28 | 1953-10-13 | Goodrich Co B F | Pressing apparatus for footwear and the like |
-
1951
- 1951-01-22 US US207106A patent/US2698976A/en not_active Expired - Lifetime
-
1952
- 1952-04-03 US US280223A patent/US2715758A/en not_active Expired - Lifetime
-
1954
- 1954-04-02 FR FR1099258D patent/FR1099258A/fr not_active Expired
- 1954-04-05 BE BE527884D patent/BE527884A/xx unknown
- 1954-04-06 CH CH328509D patent/CH328509A/fr unknown
- 1954-04-09 DE DET9324A patent/DE1162973B/de active Pending
- 1954-06-16 GB GB17698/54A patent/GB750979A/en not_active Expired
- 1954-06-16 GB GB17699/54A patent/GB750980A/en not_active Expired
-
1955
- 1955-09-12 FR FR69675D patent/FR69675E/fr not_active Expired
- 1955-09-12 BE BE541229D patent/BE541229A/xx unknown
- 1955-09-13 CH CH340315D patent/CH340315A/fr unknown
- 1955-09-13 GB GB26215/55A patent/GB798854A/en not_active Expired
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US318784A (en) * | 1885-05-26 | Matthew e | ||
US331208A (en) * | 1885-11-24 | Matthew b | ||
US408386A (en) * | 1889-08-06 | Sand molding machine | ||
US1352295A (en) * | 1920-09-07 | Molding-machine | ||
DE323380C (de) * | 1913-07-01 | 1920-07-21 | Hugh Victor Mac Kay | Formmaschine mit einem von einem Rande umgebenen elastischen Kissen |
US2335560A (en) * | 1940-11-26 | 1943-11-30 | Morton Brayton | Laundry apparatus |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2805455A (en) * | 1957-09-10 | whitesell | ||
US2847735A (en) * | 1958-08-19 | butler | ||
US2854712A (en) * | 1958-10-07 | Molding machine | ||
US2962775A (en) * | 1960-12-06 | rekart | ||
US3289256A (en) * | 1966-12-06 | Mold compacting apparatus | ||
US2847736A (en) * | 1954-12-31 | 1958-08-19 | Pulvermacher Dietrich | Device for making sand molds for metal casting |
US2852820A (en) * | 1955-03-14 | 1958-09-23 | Taccone Pneumatic Foundry Equi | Molding machine with roller strike off |
US2835004A (en) * | 1955-08-29 | 1958-05-20 | Crane Co | Bulb guide on molding diaphragm |
US2767446A (en) * | 1955-09-12 | 1956-10-23 | Kelsey Hayes Wheel Co | Molding machine |
US2864136A (en) * | 1955-09-19 | 1958-12-16 | Taccone Pneumatic Foundry Equi | Combination lateral and vertical pressure diaphragm molding machine |
US2903762A (en) * | 1957-09-18 | 1959-09-15 | Donald C Caudron | Method and apparatus for forming cores |
US3089206A (en) * | 1958-01-13 | 1963-05-14 | Osborn Mfg Co | Blow and squeeze molding machine and method of molding |
US2968846A (en) * | 1958-03-05 | 1961-01-24 | Osborn Mfg Co | Foundry molding machine |
DE1166420B (de) * | 1958-05-19 | 1964-03-26 | Russell William Taccone | Membran-Pressformmaschine zur Herstellung von Giessereiformen |
US3168764A (en) * | 1958-07-09 | 1965-02-09 | Osborn Mfg Co | Foundry molding machine and method of molding |
US2973562A (en) * | 1958-08-04 | 1961-03-07 | Osborn Mfg Co | Mold blowing and squeeze machine |
DE1225821B (de) * | 1959-04-09 | 1966-09-29 | Osborn Mfg Co | Sandblasmaschine mit Membranpressvorrichtung zur Herstellung von Formen fuer Giessereizwecke |
US3318629A (en) * | 1965-04-09 | 1967-05-09 | Jr Richard W Brandt | Tree-clamping jaws with deformable pads containing granular material |
US3890830A (en) * | 1972-12-13 | 1975-06-24 | Gerhard J Dyck | Grain moisture tester |
US4452056A (en) * | 1983-04-27 | 1984-06-05 | Pellerin Milnor Corporation | Liquid extracting apparatus |
Also Published As
Publication number | Publication date |
---|---|
GB798854A (en) | 1958-07-30 |
CH328509A (fr) | 1958-03-15 |
DE1162973B (de) | 1964-02-13 |
GB750980A (en) | 1956-06-20 |
FR1099258A (fr) | 1955-09-01 |
US2715758A (en) | 1955-08-23 |
BE527884A (fr) | 1956-12-21 |
BE541229A (fr) | 1959-08-14 |
CH340315A (fr) | 1959-08-15 |
FR69675E (fr) | 1958-11-08 |
GB750979A (en) | 1956-06-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2698976A (en) | Machine for making molds | |
US2588669A (en) | Machine for forming molds | |
US3528481A (en) | Core making machine with hardening gas manifold | |
US3293703A (en) | Vacuum molding apparatus | |
US2937421A (en) | Machine for making molds for centrifugal castings | |
US4593740A (en) | Method and apparatus for freeing a pattern or shaping element from foundry material | |
US2791013A (en) | Sand blowing machine | |
JPS625701B2 (fr) | ||
US2962776A (en) | Double diaphragm molding machine | |
US2740243A (en) | Bag sealing machine | |
US3089206A (en) | Blow and squeeze molding machine and method of molding | |
US2864136A (en) | Combination lateral and vertical pressure diaphragm molding machine | |
US1950632A (en) | Core forming mechanism | |
US1480749A (en) | Molding machine | |
US3038221A (en) | Device for hardening foundry cores and foundry moulds by means of gaseous or atomized reagents, particularly co2 gas | |
JPS5841932B2 (ja) | 鋳型の連続造型装置 | |
US331208A (en) | Matthew b | |
US3540520A (en) | Foundry molding machine with sand valve seal and diaphragm blow valve means | |
KR20090101466A (ko) | 조형기 및 조형방법 | |
US1403809A (en) | Molding machine | |
US2209792A (en) | Molding machine | |
GB637002A (en) | Improvements in or relating to machines for making foundry cores and moulds | |
US1480747A (en) | Means for venting core boxes | |
US2854712A (en) | Molding machine | |
US1034336A (en) | Method and apparatus for making molds and cores. |