US3651860A

US3651860A - Apparatus for casting metal articles

Info

Publication number: US3651860A
Application number: US565912A
Authority: US
Inventors: Arthur W Ebeling
Original assignee: Amsted Industries Inc
Current assignee: Amsted Industries Inc
Priority date: 1966-07-18
Filing date: 1966-07-18
Publication date: 1972-03-28
Anticipated expiration: 1989-03-28
Also published as: DE1558165B1; SE324040B

Abstract

A mold having a bottom opening is secured to a car that is movable to and from a pouring tube that is engaged with a ladle of molten metal. The bottom opening and pouring tube are fluidly communicable through an ingate assembly that may be pivoted into airtight engagement with the mold assembly and lowered onto the pouring tube. After molten metal is passed into the mold through the ingate assembly and solidifies, the ingate assembly may be pivoted away from the mold assembly thereby breaking the metal in the ingate assembly away from the metal in the bottom opening.

Description

United States Patent Ebeling [4 1 Mar. 28, 1972 [54] APPARATUS FOR CASTING METAL ARTICLES [72] Inventor: Arthur W. Ebellng, Elmhurst, 111.

21 Appl. No.: 565,912

[52] 11.8. CI ..l64/339, 164/337 Takacs et a1. ..164/337 X 2,675,584 4/1954 Fienberg et a1. ..25/D1G. 27 3,435,884 4/1969 Orris et a1 164/341 2,963,308 12/1960 Valentyne et a1 ..,.74/1 10 X FOREIGN PATENTS OR APPLICATIONS 851,662 10/1952 Germany 164/306 Primary Examiner-Robert D. Baldwin Attorney-Walter L. Schlegel, Jr. and Spencer L. Blaylock, Jr.

[ ABSTRACT A mold having a bottom opening is secured to a car that is movable to and from a pouring tube that is engaged with a ladle of molten metal. The bottom opening and pouring tube are fluidly communicable through an ingate assembly that may be pivoted into airtight engagement with the mold assembly and lowered onto the pouring tube. After molten metal is passed into the mold through the ingate assembly and solidifies, the ingate assembly may be pivoted away from the mold assembly thereby breaking the metal in the ingate assembly away from the metal in the bottom opening.

3 Claims, 2 Drawing Figures PATENTEDMAR28 1972 SHEET 1 [1F 2 APPARATUS FOR CASTING METAL ARTICLES This invention relates generally to an apparatus for casting metal articles and more particularly to an apparatus for bottom pressure casting metal articles.

It has been proposed to bottom pressure cast metal articles by placing a movable mold in position over a pouring tube of a conventional bottom pressure casting apparatus. After the mold is filled, the flow of metal into the mold is shut off, the mold is removed from its position over the pouring tube, and a new mold is moved into position. Each mold is provided with an ingate assembly which provides communication between the pouring tube and the lower end of the mold. The ingate assembly carries with it a slide cutoff which is utilized to terminate flow of metal into the mold. Such an apparatus is shown in U.S. Pat. No. 3,015,863 to C. F. Strorn et al.

The ingate assembly is carried by the mold carriage away from the pouring tank. Operation of this apparatus has been successful. However, one drawback does exist in that the metal between the slide cutoff and the mold is difficult to remove. It sometimes freezes the ingate assembly to the metal in the mold, which necessitates the use of a sledge hammer to remove the ingate assembly. This invariably damages the ingate assembly, thereby increasing the cost of the casting operation.

It is, therefore, an object of the present invention to provide a bottom pressure casting apparatus wherein the above described difficulties are eliminated.

It is another object of the invention to provide a bottom pressure casting apparatus with an efficiently operating ingate assembly.

Another object of this invention is to provide an improved ingate assembly.

These and other objects and advantages of this invention will appear from a reading of the following detailed description of this invention when taken in conjunction with the accompanying drawings wherein:

FIG. 1 is a side elevational view in cross section of the apparatus of this invention, and

FIG. 2 is a front elevational view in cross section of the same apparatus.

Referring now to the drawings, reference numeral denotes a mold apparatus which is mobile and adapted to be moved on wheels (not shown) into position over a pouring tank 12 of a conventional bottom pressure casting apparatus. Reference may be had to copending application Ser. No. 382,533, filed July 14, 1964, entitled Casting Apparatus, for details of the construction and operation of the mold 10. Since all of the details of the construction of the mold 10 are shown in the above application, all that is required for an understanding of this invention is a schematic showing of the mold in the drawings. As shown it comprises a left side block 14, a right side block 16, a bottom block 18 and a front end block 20. The top and rear end blocks are not shown.

The mold 10 is positioned with raised ingate assembly 22 over the pouring tube 24 of the tank 12. The pouring tube 24 extends from outside of the cover 12 and projects into the molten metal 26 contained in the ladle 28. As will be described herein, the mold 10, the ingate assembly 22, and the pouring tube 24 are placed in sealed relationship with each other. The molten metal 26 may then be forced upwardly through the tube 24, the ingate assembly 22, and into the mold 10 by air pressure produced in the tank 12 by suitable conventional means (not shown).

The ingate assembly 22 comprises a housing 30 having a cylindrical opening 32 extending therethrough, which receives therein a bushing 34 of suitable ceramic material. The housing 30 has a horizontal slot 36 extending therethrough to receive a slide or cutoff plate 38. The slide 38 is provided with an opening 40 of substantially the same diameter as opening 32. A bushing 42 of suitable ceramic material is positioned in opening 40 and its inner diameter is substantially equal to the inner diameter of bushing 34. The slide 38 is provided with a solid flat portion 44 which is of greater length and width than the here 46 of the bushing 42. When the slide 38 is activated to shut off flow of molten metal through the ingate assembly 22, this portion 44 is moved across the slot 36 to a position covering the bore 48 of the bushing 34, thereby shutting off flow of metal therethrough. Reference may be had to the aboveidentified patent for details of the construction and operation of slide 38.

The housing 30 of the ingate assembly 22 is constructed in the nature of a spool having a reduced central portion 50, a radially enlarged upper portion 52, and a radially enlarged lower portion 54. The enlarged upper portion is provided with a substantially flat horizontal under surface 56 and the enlarged lower portion 54 is provided with a substantially flat horizontal upper surface 58, the function of which will be explained hereinafter.

On opposite sides of reduced central portion 50 and between flat surfaces 56 and 58 are positioned two arms 60 of lever mechanism 62. The two arms 60 extend from fulcrum 64, rotatably secured in a conventional inanner to the main carriage of the mold 10. For example, the fulcrum is rotatably mounted in a bushing 65 retained in an opening 67 of a support 69 of the mold carriage. The two ends 66 of the arms 60, remote from the fulcrum 64, are joined together by pin 68. Intermediate the end 66 and the fulcrum 64, the arms 60 are provided with recesses 70 which receive therein spring members 72. Each of these spring members 72 rests against the flat surface 56 of the upper enlarged portion 52 of the housing 30. The function of these springs will be explained hereinafter. Extending from and secured to fulcrum 64 in the direction opposite that of arms 60 is a lever arm 74 whose end 76 remote from the fulcrum 64 is secured to a conventional mechanical screw jack 78. The jack 78 is also carried by the main carriage of the mold 10.

In operation, the mold 10 is rolled into position over the pouring tube 24 .of the tank 12. The jack 78 and lever arm 74 are in the position shown in full lines in FIG. 1. The springs 72 exert pressure against the flat surfaces 56, forcing the housing 30 upwardly into airtight engagement with the opening 80 of the mold 10. The mold l0 and ingate assembly 22 are then lowered as a unit by a conventional jack or other mechanism (not shown) in order that the ingate assembly may be brought into airtight engagement with the pouring tube 24. Pressure is supplied to the tank 12 to force the molten metal 26 upwardly through the pouring tube 24 into and through the ingate assembly 22 to completely fill the mold 10.

After the mold has been filled, the slide cutoff 38 is moved to the right, shutting off flow of metal through the ingate assembly 22. The pressure in the tank is relieved, permitting the metal in the tube and in the ingate 22 below the slide to return to the ladle 28. The mold is then raised from the pouring tube 24 and rolled to a remote position for solidification of the article in the mold. After the article in the mold has substantially solidified, the jack 78 is activated to raise the lever arm 74 to the dotted line position shown in FIG. 1. This upward movement of lever arm 74 causes the fulcrum 64 to rotate in the direction shown by the arrow in FIG. 1 and brings the arms 60 into engagement with the flat surfaces 58 of the lower enlarged portion 54. This causes downward movement of the ingate assembly 22 breaking away from the mold opening 80 and stripping that portion of the metal in the ingate 22 above the slide cutoff 38.

It can be seen from the foregoing that the operation of the apparatus of this invention facilitates removal of the ingate assembly 22 from the mold 10 and thereby avoids the difficulties of the prior art devices. It should be understood that various modifications may be made in this apparatus without departing from the spirit and scope of the following claims.

I claim:

1. In a gate assembly adapted for use with a bottom pressure casting machine and through which molten metal passes to the mold assembly comprising:

a frame,

a gate housing, including a molten metal passageway. and

having one end adapted to be brought into a sealed condition with a portion of the mold,

a carrying arm on said frame freely engaging said housing and projecting away from one side thereof,

a mechanical self-locking device connected to said arm to vertically displace said arm and, hence, move said housing towards and away from said mold assembly,

a power means connected to said device for causing operation of said device,

said power means characterized in having the capacity to at least momentarily deliver the required sealing force between said housing and said mold assembly, and

wherein said self-locking device has means to maintain said sealing force on a reduction or discontinuation of the force developed by said power means.

2. In a gate assembly according to claim 1 wherein a pair of openings is formed in said housing:

said arm comprising a pair of fingers, one of which extends into one of said housing openings and the other of which extends into the other of said housing openings:

a shaft located on one side of said housing carrying said fingers in a manner that the fingers and the shaft form a three-sided channel into the open end of which is received said housing; and

means for holding said housing on said arms.

3. In a gate assembly according to claim 1, in which said arm is connected to said self-locking device by a shaft,

said self-locking device comprising a single screw jack having a gear ratio and pitch characteristic so as to hold the arm and, hence, the gate assembly at a force substantially equal to that developed by said power means, and

wherein said power means comprises a motor.

Claims

1. In a gate assembly adapted for use with a bottom pressure casting machine and through which molten metal passes to the mold assembly comprising: a frame, a gate housing, including a molten metal passageway, and having one end adapted to be brought into a sealed condition with a portion of the mold, a carrying arm on said frame freely engaging said housing and projecting away from one side thereof, a mechanical self-locking device connected to said arm to vertically displace said arm and, hence, move said housing towards and away from said mold assembly, a power means connected to said device for causing operation of said device, said power means characterized in having the capacity to at least momentarily deliver the required sealing force between said housing and said mold assembly, and wherein said self-locking device has means to maintain said sealing force on a reduction or discontinuation of the force developed by said power means.

2. In a gate assembly according to claim 1 wherein a pair of openings is formed in said housing: said arm comprising a pair of fingers, one of which extends into one of said housing openings and the other of which extends into the other of said housing openings: a shaft located on one side of said housing carrying said fingers in a manner that the fingers and the shaft form a three-sided channel into the open end of which is received said housing; and means for holding said housing on said arms.

3. In a gate assembly according to claim 1, in which said arm is connected to said self-locking device by a shaft, said self-locking device comprising a single screw jack having a gear ratio and pitch characteristic so as to hold the arm and, hence, the gate assembly at a force substantially equal to that developed by said power means, and wherein said power means comprises a motor.