US2104380A - Centrifugal casting machine - Google Patents

Description

Jan. 4, 1938. E. G. TOUCEDA 2,104,380

CENTRIFUGAL CASTING MACHINE Filed May 5, 1934, 2 Sheets-Sheet l Y TOR K ywifim Jan. 4, 1938.

E. G. TOUCEDA CENTRIFUGAL CASTING MACHINE 2 Sheets-Sheet 2 Filed May 5, 1934 & II:J%I INTOR X BY A'ITORNE Patented Jan. 4, 1938 UNITED STATES PATENT OFFICE CENTRIFUGAL CASTING MACHINE Enrique G; Touceda, Albany, N. -Y., assignor to Consolidated Car-Beating Company,

Inc.,

Albany, N. Y., a corporation of New York Application May 5, msns rm No. 724,005

Claims.

ed upon the same rotatable member as the device for melting the necessary metal.

A further object of the invention is the pro- 15 duction of a device of the type described which me'nt selected to illustrate the invention prorasses, and the novel features will be particularly pointed out in the appended claims.

In describing the invention in detail and the particular physical embodiment selected to illustrate the invention, reference will be had to the accompanying drawings and the several views thereon, in which like characters of reference designate like parts throughout the several views, 30 and in which:

Figure 1 is a side elevational view of a device embodying my invention; Fig. 2 is a top plan view of the device as shown by Fig. 1; Fig. 3 is a vertical sectional view of the device on the 35 plane indicated by the line III-III of Fig. 2, viewed in the direction'ofthe arrows at the ends of the line; Fig. 4 is a horizontal sectional view onthe plane indicated by the line IVIV of Fig. 3, viewed in the direction of the arrows at 40 the ends of the line; Fig. 5 is a vertical sectional view on the plane indicated by the line V-V of Fig. 33, viewed in the direction of the arrows at the ends of the line; Fig. 6 is a diagrammatic view illustrating a method of controlling elec- 45 trical energy for the device of Fig. 1.

The device, in general, includes an electric furnace designated, generally by F, mounted so as to communicate with the inlet of a mold M so that metal melted within the furnace F may 50 flow into the mold M when both. mold and furnace are rotated about a center. In order to secure the desired rotation, both the furnace F and the mold lvI aremounted upon an arm A which in turn" is mounted upon therotatable -55 spindle S. When the spindle S iscaused 'to..ro-'

tate the arm A is rotated withit so swinging the furnace F and mold M about the longitudinal axis of the spindle S whereby melted metal in the'furnace F is thrown by centrifugal force into the molcl M.

The particular specific embodiment of applicants invention shown in the drawings includes a substantially hollow, preferably cylindrical base member I. This bye member I is preferably provided with a iia ge 2 apertured, 10 as at 3, for the reception of bolts or screws whereby the base may be secured to a suitable support.

Preferably within the base member I, an en bearing is provided for the spindle S. This end bearing preferably includes an end plate 4 of appropriate material to take the end thrust of the spindle S and a ball bearing 5 of usual or appropriate form held in place by the annulus 6 and screws 1 to provide anti-friction means for allowing the rotation of thespindle S and for appropriately maintaining a fixed position for the lower end of the spindle S.

Shoulders 8 are provided on the interior of the wall of the base I. A plate 9 is supported 2: by these shoulders 8 and in turn serves to sup.- port a spiral spring I8, one end I I of which is attached, as by screw I2, to the base I, and

the other end I3, of which is attached to the sleeve I4 which is free on spindle S so that spindle S may rotate independently of sleeve I4 although sleeve, I4 does not move longitudinally of spindle S being supported by spring III and prevented from too great movement downwardly by plate 9. m,

The sleeve M has its upper end, as viewed in Fig. 3, formed into ratchet teeth I6 mating with ratchet teeth I 1 formed in the lower end of a. sleeve I8 about the spindle S: This sleeve I8 is freely movable longitudinally of the spindle S, 40 but is rotatable therewith by reason of the longitudinal slot I9 in the collar I8 and the pin 20 in the spindle S.

The construction heretofore described is such that if the spindle S is rotated in a clockwise direction, the pin 20 causes the sleeve I8 to turn thereby causing the teeth I! to engage with the teeth IS on the sleeve I4 thereby causing sleeve H to rotate in a clockwise direction which causes the spring III to be tension'ed or wound up. If the spindle S is then freed, it will rotate in a counter-clockwise direction being driven by the spring III through the sleeve I4 and its teeth I6 meshing with teeth I! of sleeve I8 which bearing against pin 20 causes the spindle S to rotate in 5 a counter-clockwise direction. If the spindle S or any parts attached thereto have considerable inertia therein after the spring l8 has been completely unwound there will be a tendency for the spindle S to continue its rotation. This may be done without winding the spring in the opposite direction, that is, in a counter-clockwise direction because when the spring has become completely unwound and the spindle S still continues to turn, the teeth I! of the sleeve l8 will ride up over the teeth l6 of the sleeve l4, being permitted by the slot IQ of the sleeve l8, so that spindle S can continue to turn until stopped by friction without winding the spring M in a counterclockwise direction.

. In order to suitably journal the upper end of the spindle S applicant provides a base cap 2| attached to the base l as by screws 22. This base cap is provided with an orifice 23 through which the spindle extends and properly supports a ball bearing 24, the inner race of which is attached to the spindle S so that the spindle S is suitably supported in an anti-friction manner enabling it to rotate freely, but is prevented from longitudinal movement by the base plate 4 and the collar 25 fixedly attached thereto and bearing against the ball bearing 24.

At the upp r end of the spindle S, a pin 26 is passed through the spindle and through the hub 21 of arm A. This binds the arm A to the spindle S so that the arm A must turn with the spindle S but the fit between the spindle S and the hub 21 is such that the arm A can pivot slightly at the pin 26 so that if the arm A is heavier at one and than it is at the other it will be shown by the slight pivoting, and, as will hereinafter be shown, may be corrected by a weight adjustment.

The arm A is provided on each side with trackways 28 for receiving slides 29 held to carriage 38 by appropriate means such as screw 3|. This trackway 28 extends longitudinally of the arm A and so allows the furnace carriage 38 to move longitudinally of arm A.

The furnace carriage 38 supports heat insulation material 32 which in turn supports what I term, an outer crucible cover 33, which is preferably made of a refractory material which can withstand a very intense heat without melting. Within the covering 33-is a trough-like member 34 which is the resistance element of an electric resistance furnace and to the ends of which the terminals of a source of electrical energy are connected. This trough-like member 34 is made preferably of recrystallized silicon carbide, which is a material having a negative resistance characteristic upon heating, and is at the same time infusible at the temperatures at which it is desired to operate, and is also quite fairly stable when heated in the presence of air. This troughlike member 34 may be formed in a variety of ways but applicant has found that an appropriate way is to grind out, into the form of a trough, one of the ordinary refractory recrystallized silicon carbon rods now sold as an article of commerce, although direct moulding thereof may be preferable.

The element 34 is the element which is heated by the passage of electric current and may well serve, in many cases, as the direct receptacle for the material to be melted so that the element 34 may well be called a crucible and may actually be used as a crucible. In some cases, however, applicant prefers to place a lining within the trough-like member or resistance element 34 to act as the direct receptacle for the material to be melted. In case such inner lining is used, such as 35, it would be made of highly refractory material so as to withstand the great heat to which it is subjected and would preferably be formed as best shown in Fig. 3, that is, with a prolonged neck 36 serving as an outlet duct, and would be open at 31 so that the material to be melted could be placed therein from above. In order to facilitate the placing of material within the crucible, applicant provides a removable cover 38 which may be taken away from in place, as shown in the drawings, while metal is being placed within the crucible or within the inner lining 35 thereof, and applicant further provides a peephole 39 through which the metal being heated may be viewed and through which any gases which may be generated may issue.

In order to transmit the electric current to the crucible 34, applicant preferably provides a conducting block abutting each end. -As shown in Fig. 3, one abutting block 40 is at one end and a similar abutting block 4| is at the other end. These blocks are made preferably of conducting carbon and are preferably formed with grooves 42 therein in which the end of the crucible 34 rests. In order to make a more perfect electrical union between the crucible 34 and the end blocks 48 and 4|, applicant prefers to place a conducting cement such as an electric graphite cement between the several parts.

The current is conducted to the carbon blocks by means of copper plates such as 43 and 44 abutting the carbon blocks 48 and 4| respectively. These copper plates 43 and 44 and the blocks 48 and 4| are held in copper stirrups 45 and 46.

The copper stirrup 46 is insulated from the frame 38 by a mica plate 41, and the parts 4|, 44, 46, 41 and the abutment plate 48 of carriage 38 are allheld firmly and rigidly together by bolts as 49, best shown in Fig. 2. These bolts have insulation under their heads and surrounding them so as to prevent an electrical connection to the carriage 38.

The members 48, 43, and 45 are held together by bolts, as 5| and 52, together with a mica plate 53 and an apertured steel plate 54. The form of construction adopted is such that all of the parts are held together and the apertured metal plate 54 is positioned to receive the end of a plunger 55 against the mica. plate and within the aperture 56 of the steel plate 54. The mica also serves as a heat insulator to prevent too great heating of 55.

The plunger 55 has a feather 51 therein which works in a keyway within the plunger shoulder 58 so that the plunger 55 is movable longitudinally but cannot rotate upon its own axis.

The plunger 55 is provided with an internal screw thread and a screw threaded rod 68 attached to a hand wheel 6| cooperates therewith. When the hand wheel 6| is rotated in a clockwise direction the plunger 55 is withdrawn, taking with it a metal plate 54, mica plate 53, stirrup 45, connector plate 43 and carbon contact 48, as 54 fits tightly on 55 and is preferably silver soldered thereto. When the hand wheel 6| is rotated counter-clockwise the plunger 55 is in effect merely spring pressed by the spring 62, that is the rotation of the hand wheel 6| cannot force plunger 55 into engagement with mica plate 53, but it can, in effect, release plunger 55 so that the spring 62 will press it into contact with mica plate 53. In order to have plunger 55 so act, spring 62 surrounds rod 60 and at one end presses against plunger 55 through the intermediary of spring,

seat 83 and at the other end presses againstru standard 84 through the intermediary of spring seat 88. Y Y

The eifect of the construction described, is that the several parts at each end of the crucible and the crucible 84 are tensioned to an extent depending upon the force exertable by the spring 82 I, so that the danger of crushing crucible and the associated parts is avoided, and if during heating the several parts expand, then expansion may be taken up by the spring 82.

In order to conduct current to the copper plate 48, a jumper 88 made of conducting material is connected from the copper plate to the carriage 88. The carriage 88 is in good electrical and mechanical contact with arm A through the bars 28. The arm A is connected by conducting jumper 81 to copper sleeve 88 positioned on spindle 8 and a conducting brush 88 bears upon the sleeve 88 and is supported by and attached insulatingly to the member. 2i by means of the screw 18 by which the electrical conductor from one side of a source of potential may be connected to-the device.

The copper plate 44 is connected through the conducting jumper H to the conducting plates 12 insuiatingly supported by insulation 18 upon the carriage 88 by means of bolts, as 14 and 18. Cooperating with the plates 12 is the conducting plow or wedge 18 insulatin'gly supported by insulation 11. bolted to the carriage 88 and having connected thereto a conducting jumper 18 passing down under and up as shown in Fig. 5 and attached by bolts, as 18, and insulation as 88, to the face of the arm A in position to be engaged by a reciprocating plunger 8i.

The reciprocating plunger 8i is made of conducting material and is preferably constructed with its upper end having an overhanging shoulder, as 82, which may rest on the top of the member 18. The plunger 8i passes through a bore 88 of a plunger carrier 84 supported on the member 2 I but insulated therefrom as by insulation 85 and bolted thereto, as by bolts 88, insulated from the plunger carrier 84. The plunger carrier 84 is further provided with any suitable means, such as contact clip 81 held by screw 88, by which a conductor from one side of the source of potential may be connected thereto.

For the purpose of properly holding a mold into which metal is to be poured applicant provides the mold standard 88 forming part of the the interior of the'extenslon 88 of the crucible I lining 38.

In making use of the device the mold M is put in place and secured by turning the screw rod 88 and the crucible 84 with its associated and surrounding parts are positioned as shown in Fig. 3 and the hand wheel 8i is turned counterclockwise, until the full force of the spring 82 is exerted upon the parts so as to properly hold them together. The metal to be melted is placed in .the crucible, or crucible lining, as the case may be, after removing the cover 88. The cover 88 is then. replaced and observation is made to see whether ornot the arm is balanced. If it is not balanced then the ratchet 88 is moved out of the teethofthe rack 81 against the spring by pressingupwardly, as shown in Fig. 1. on them 88 of the two arm lever pivoted at I88 on the weight member l8l, and'the weight "I is moved along until the arm A is in balance and then the ratchet freed to re-engage the raek 81. Terminals from a source of potential are eonnected one to 18 and the other to 81. The plunger 8| is -moved upwardly so that its overhanging shoulder 82 engages the top of the member 18 after the spring- I8 has been wound up by a clockwise movement of the arm A.- The plunger 8i prevents the spring from unwinding and also conducts the current to the wedge or plow 18. The passage of current through the crucible 84 generates heat suilicient to melt the metal within the crucible or the lin ing 88. when the lining is used the metal doesthe spindle S so as to throw the melted metal into the inlet 88 of the mold M and so fill the impression in the mold to give the desired article.

In order-to prevent the carriage 88 from moving when the mold M is pushed up against it the spring catch I88 is positioned on the carriage 88 to engage with a shoulder I84 on the arm A.

A suitable method of supplying current to the device is shown by Fig. 6 in which the connections from a source of potential are indicated as I88 and I88. One of these, I88, is connected to the center I81 of an ordinary switch arm which is mounted to turn to contact successively the contact points I88, I88, II8, "L1", and I Irrespectively which are tapped into the primary II4 of a transformer of which the secondary is I I8. By this arrangement various voltages may be generated at the terminals of the secondary H8 as de sired. The secondary II8 has one terminal II8 connected to 18 of Fig. 3 and the other terminal H1 is connected through an ammeter II8 to any suitable form of overload circuit breaker I I8 and then by wire I28 to the'terminal 81 as shown in Fig. 3. By this arrangement the desired flexibility and desired energy supply to the crucible is obtalned.

Although I have particularly described one particular physical embodiment of my invention and explained the operation, construction and principle thereof, nevertheless, I desire to have it understood that the form selected is merely illustrative, but does not exhaust the possible physical embodiments of the idea of means underlying my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

.1. In an electric furnace, in combination: a crucible formed as an elongated trough, open at each end and formed of refractory electrical conducting material; refractory electrical conductingblocks. one applied removably to either end of the trough and serving to close the same at one end while the other block has an orifice to permit discharge of fused material endwise from the trough: metallic conducting plates, one bearing against each block; and means for applying a diiference of potential to the metallic. conducting plates.

'2. In a centrifugal casting machine, in com...

4 arouse bination: an arm mounted for rotation and supported intermediate its ends; an electric furnace mounted on the arm, said electric furnace including a somewhat elongated trough-like member formed of refractory electrical conducting material; means for mounting a mold upon the arm, said mold formed with an inlet positionable to communicate with the trough oi the crucible; means for applying a difference of potential to the ends of the crucible whereby material therein may be melted; and means for rotating the arm whereby the melted material in the crucible is moved .by centrifugal force into the mold, said instrumentalities being arranged in approximately balanced position relatively to the axis of rotation of said arm, so that the moment of centrifugal forceis exerted chiefly upon said melted material.

3. In a centrifugal casting device, in combination: an arm mounted for rotation; an electric furnace mounted on the arm and formed with an outlet and terminals; a mold mounted upon the arm and formed withan inlet aligning with the outlet of the furnace; a carriage upon which the furnace is mounted; means for sliding the carriage longitudinally of the arm and for securing it in an adjusted position; means for rotating the arm; means for preventing rotation of the arm also serving to conduct electricity to one terminal of the furnace; and means for conducting electricity to the other terminal of the furnace, said instrumentalities being adjustable into approximately balanced position relatively to the axis of rotation of said arm, so that the moment of centrifugal force may be exerted chiefly upon the molten material.

4. In a centrifugal casting device, in combination: an arm; a spindle pivotally supporting the arm intermediate its ends: means for supporting a mold formed with an inlet on the arm; a furnace carriage; cooperating slides and slideways on the carriage and the arm whereby the carriage may be slid longitudinally of the arm; a somewhat elongated trough-like crucible formed of refractory electrical conducting material supported by the carriage; means for connecting one side of a source of potential to one end of the trough-like crucible including a refractory electrical conducting block bearing against one end of the crucible, a metal conducting plate bearing against the refractory block, spaced plates supported by the carriage and electrically connected to the metal plate, a wedge positioned .on the arm to engage between the plates, and

a conductor extending from the wedge to a side face .of the arm, and an electrical connection from the said side plate to one side of a source of potential; means for connecting the other end of the crucible to the other side of the source oi potential; and means for rotating the arm whereby material placed in the crucible may be melted and I thrown by centrifugal force into the mold.

5. In a centrifugal casting device, in combination: a rotatable member, an electric resistance furnace'mounted on the rotatable member and including, resistance element formed into substantlally an elongated hollow trough; a mold formed with an inlet communicating with the hollow trough; resilient means to bias said trough and moldinto cooperative relation; means for applying electric energy flow through the resistance element; means for .at times rotating the rotatable member whereby metal may be melted within-the trough thrown by centrifu 1 gal force intothe mold, a; movable abutment roisaid resilient means, .and a quick-acting manually operable device to'shift said abutment, so

that said mold and said trough are respectively and independently readily demountable.

ENRIQUE G. TOUCEDA.

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