US1054789A

US1054789A - Die-casting machine.

Info

Publication number: US1054789A
Application number: US67362812A
Authority: US
Inventors: Layton M Parkhurst
Original assignee: INDIANA DIE CASTING DEV Co
Current assignee: INDIANA DIE CASTING DEVELOPMENT Co; INDIANA DIE CASTING DEV Co
Priority date: 1912-01-26
Filing date: 1912-01-26
Publication date: 1913-03-04
Anticipated expiration: 1930-03-04

Description

' L. M. PARKHURST.

DIE CASTING MGHINB. APPLmATmNnLm JAN. ze, 1912.

`Patented Mar. 4, 1913.

. mf)- I-' WITNESSES.

A TTORNE Y.

ENTTED sTATEs EATENT oEErcE.

LAYTON M. PARKHURST, OF INDIANAPOLIS, INDIANA, ASSIGNOR ,'lfO THE INDIANA DIE CASTING DEVELOPMENT COMPANY, A CORPORATION 0F INDIANA.;

DIE-CASTING MACHINE.

Specification of Letters Patent. i

do hereby declare t-hat the following is a full, clear and exact description thereof,

reference being had to the accompanying drawings.

The object of this invention is to improve the Construction and operation of stationary die Cast-ing machines whereby the manufacture of castings from certain metals will be facilitated and their quality, particularly theirl density, be improved. y

The chief feature of the invention consists in utilizing the products of Combustion for forcing the molten metal out of the Crucible into the die. It is accomplished by reversing the movement of the products of Combustion by introducing compressed air into the exhaust passageway far enough away from the Crucible so that the pressure of the air will force theproducts of Combustion backward under sufficient pressure to force out the molten metal and keep the air entirely out of Contact with the metal. Also a floating plunger plate rides loosely upon the metal .in the Crucible and around the outlet pipe therein. The foregoing not only facilitates the operation of such a device, but it enables the use of'compressed air or the like for causing the discharge of the metal into the mold without said air or the .like coming into Contact with'the molten metal. This prevents oxidation and other disadvantages resulting from an outer contact of the air or the like with the molten metal. It also simplies. the construction and mode Aof operation of the mechanism.

The nature -of the invention will be understood from the accompanying drawings andv v line 2+2 of Fig. 1. Fig. 3 is thedisk plunger shown in perspective.

In detail there is shown a semi-spherical melting oven 10 ixedly supported by the arms 11 on triangular end frames 12 which are held in place by Cross bars 13. The sort of frames whereby the melting oven 10 is secured rigid inplace is immaterial to the invention. The oven is open at the top 'and provided with a slightly beveled mouth 14 so that the top 15 can wedge vdownA ito place and fit tightly. The top 15 has a centrally located outletopening 16 for the molten metal, the lower part of said opening being threaded to receive a tube 17 which extends downward and the upper part of the opening 16 is surrounded by an annular projection 18 which surroundsa projection 19 on the lower part 2O of the die whereby the die is centered and held in place. The upper member 21 of the die is held in place beneath the lower end .of a screw 23 which screws through a frame 24 and is turned by a wheel 25. In this manner the die is held upon the top 15 and outlet 16 from the .Crucible vand after releasing, the screw 23 may be removed. The die may be of the usual Construction.

The melting oven 10 is provided with suitable fire clay lining 26 and within said oven there is a Crucible 27 having an oval bottomV The tube 17 projects down near the bot-torri o f the Crucible and below the wider'po'rtio thereof which is of the same diameter as the plunger so that 'said disk plslnger"` vcannot move so low in the Crucible as to escape' from the outlet tube 17. The Crucible extendsu'p within the proximity of 'the -to 15, but 'a space 30 is left between said "p and' the' Crucible for the passage of Compressed air or gas from the oven into the upper end of the Crucible. maintained heated by gaseous fuel Coming in through a pipe 31 which is supplied with gas through a pipe 32 and air through a pipe 33. A valve 34 Controls the 'air anda valve 35 Controls thegas and the mixture. The fuel pipe 31 enters the melting -oven on one side of the Crucible and there is an exhaust port at 40 from said .oven at the other side of the Crucible through a pipe 41. There is a compressed air pipe 42 Connected with the lair exhaust pipe and having a threeway valve 43 arranged so that when the valve is in one positionz the exhaust will Patented Mar. a, wie; Application/filed January 26, 1912. Serial'No. 673,628. I

The metal in the Crucible is the outer portion of the pipe 41 and openl communication between

pipes

41 and 42 and then the compressedair will rush in from the pipe 42 through the pipe 41. There is a check valve 44 in the fuel pipe 31.

The operation is as follows: The crucible is filled with molten metal and then the disk plunger 28 is placed therein and the top put in place with the outlet tube 17 projectlng centrally through the plunger disk ,28. l 'lhe mold is moved down into a tight fit and the fuel turned into the heating chamber. This heats or maintains the heat of the'molten metal in the crucible and the heated gases` cannot reach the molten metal on account of the plunger `disk 28. The products of combustion pass out through the pi 'e 41 which serves as a sort of flue. When it 1s desired to force the metal into the die, all. that is necessary is to close the valve tostop the flow of the mixture and operate the valve 43Y so as to close the exhaust pipe 41 and turn in lthe compressed air through the pipe 42 and pipe 41. The air is under a rather high state of compression and it rushes into the chamber surrounding the crucible and over the tube in the crucible above the plunger disk and suddenly and effectively forces the disk down and thus forces the 4metal up through the tube 17 into the die.

The arrangement of the

pipes

41 and 42 andvalve 43 is not necessary, but done for convenience. The advantage of the arrangement of the

tubes

41 and 42 and valve 43 isthat only the heated gases fromthe pipe A41 would return into the outer chamber and upper end of the crucible and the cool compressed air would not reach said members and tend to cool them. As they are arranged in the drawings, the compressed air forces'the products of combustion which are held -in the pipe 41, back into the oven chamber and crucible, but with the'same degree of pressure as the compressed air possesses. That does no harm to the metal in the crucible, however. All that is necessary is that there be some exhaust pipe leading from the oven chamber and also a means for turning compressed air or the like into said chamber. It is immaterial how this is done, whether exactly as shown or otherwise.

.The compressed air tube 42 is connected with the exhaust tube 41 remotely from the outer chamber 10 so that the capacity of the portion of said exhaust tube 41 between its connection with the tube 42 and the outer .chamber will at least be equal to the un occupied space in the outer chamber l0 and the crucible 27. With this construction,

Valve 43,it will force the warm and inert gases in the tube 41 back into the unoccupied portion of the outer chamber 10 and the crucible so that the air will not enter the chamber 10. The pipe 31 has a checkvalve 44 in it which will close umder the `in fluence of the extreme back pressure caused when the compressed air is turned on through the pipe 42. With this arrangement the continuous operation of the apparatus is possible and only one valve 43 needs to be operated after the device is under way.

'Ihe outlet pipe or nozzle 17 is readily re'y movable and, therefore, can be inserted, after the metal has become heated, into the crucible and through theplun er plate'28.. This enables the tube 17 to be ifted out of the crucible while casting and then said metal can be heated outside and introduced into the crucible highly heated and the casting operation .be commenced at once. When the nozzle 17, however, is thus removed, since it is secured to the top 15, another lid should preferably be placed upon the outer chamber while the casting operation is in progress, to 4keep the metal hot until time begin the casting operation.

I- claim as my invention:

1. A die casting machine including a crucible, a conduit from the lower part thereof through which the metal may be forced to a die, means for supplying heat to the crucible, and means for applying products of combustion under pressure upon the metal in the crucible for forcing the -same out through said tube.

2. -A die `casting machine including a crucible, an oven forming a chamber surrounding said crucible and in communication with the upper part thereof, a conduit from the lower part of the crucible through which the metal may be forced to a die, means for introducing heat into the oven chamber, and means for compressing the products'of combustion into said oven chamber and crucible for forcing out the metal during the casting operation.

3. A die casting machine including a crucible with an opening in the upper end, an oven surrounding said crucible leaving a chamber between the crucible and the oven in communication with the upper part of ioo connected with the exhaust tube, and a valve at the connection between said tubes for turning the compressed air into the exhaust tube and forcing the products of combustion backward into the crucible under pressure during the die casting operation.

5. A die casting machine including a crucible, a conduit -leading from the lower part thereof through which molten metal may be forced to a die, an oven forming a chamber surrounding the crucible, Valve controlled means` for introducing heat into the oven chamber, an exhaust tube leading` from the oven chamber, a compressed air tube connected with the exhaust tube' away from the oven so that the capacity 0f the exhaust tube between the compressed air tube and the oven will exceed the unoccupied space in the crucible and oven chamber, and a valve at the connection between said tubes for turning the compressed air into the exhaust tube and forcing the products of combustion backward into the crucible under pressure during the die casting operation.

6. A die casting machine including a crucible open at its upper end with an outlet for the molten metal, a plunger plate adapted to tit snugly but loosely into said crucible upon the molten metal, an outer chamber inclosing said crucible, a fuel supply tube entering said outer chamber at one side of the crucible, an exhaust tube'leading from said outer chamber at the other side of the crucible, a compressed air pipe leading to said exhaust tube, and a Valve for simultaneously opening the exhaust tube and closing the compressed air tube'when in one position and for closing the exhaust tube and opening the compressed air tube when in the other position.

v7. A die casting machine including a crucible o pen at its upper end, an oven surrounding the same, a plunger plate adapted to lie upon the metal in the crucible and having an opening therethrough, a removable tube insertible loosely through said plunger plate into the crucible, means for securing a die at the outer end of the tube, and means for introducing air under pressure into said oven and crucible.

In wit-ness whereof, l havehereunto affixed my signature in the-presence of the witnesses herein named. f

LAYTON M. PARKHURST. Witnesses:

Gr. H. BOINK,

E. H. MAYO.