US2192043A - Casting device - Google Patents

Description

Feb. 27, 1940.-

. L.. HQQPER CASTING DEVICE 2 sheets-sheet 1 Filed Aug. l5, 1938 .M /75N TOR BERT L HOOPER Feb. 27, 1940. 'I B L, HQOPERx 2,192,043

, I CASTING DEVICE Filed Aug, 15, 193s sheets-sheet 2 6 d Z5 e 7 f5 47a com . l ,g77-sf.

A Patented Feii.27,194o

UNITlszD STATES 'PATENT ori-ICE This invention relates to casting devices, and more particularly pertains to such a' device mainly for employment in dental work to produce such castings as inlays and bridges for teeth and the like.

One of the objects of the invention is to provide such a device having a rotating mould, and

wherein thev casting medium, such as gold usually employed in dental work, may be released from the melting means and directed into the mould by centrifugal force under a constant pressure While the mould is rotating at a constant high rate of speed, to produce a casting having uniformity of hardness throughout its various l5 portions.

Another object is to provide such a device wherein the gold may be brought to the proper melting point for casting, and then initially directed into the mould Within the shortest possibletime while the mould is rotating.

Another object is to provide such a device wherein the possibility of molten gold escaping from the device during the casting operation is practically eliminated.

Another object is to provide such a device having a mould constructed of a plastic substance.

such as plaster usually employed in dental work,v

and wherein the device vwill be capable of trapping any molten gold that may be discharged from the mould in the event same becomes damaged during the casting operation.

The type of casting device to which this invention relates includes'a rotating upright or shaft;

as power means for rotating the shaft at a high rate of speed; a carrier member mounted on theshaft to rotate therewith; means on the'carrier for attaching thereto to one side of the axis of the shaft any one of a number of moulds of various 40 sizes or Weight; an adjustable counterpoise on the carrier for counterbalancing the mould, and

means for directing a molten casting medium into the mould radiaiiy of the axis ofthe shaft by centrifugal force upon rotationof the shaft. To make it possible for an operator of the device to determine with a reasonable degree of certainty that the counterpoise properly counterbalances a mould placed on the carrier prepara,

tory to the casting operation, without depending vention to so mount the carrier on the shaft whereby it may pivot thereon in the manner of a scale at least prior to the casting operation, so

u that the mould may be weighed thereonI against upon guesswork, it is a further` object of this inthe counterpoise in determining the proper adjustment of the counterpoise. l

' In carrying out `the above objects, it is a further object to provide releasable holding means for holding the carrier in its balanced position on 5 the shaft after proper adjustment of the counterpoise has been made, and wherein the holding means will coact to position or support the directing means in cooperative relation with the mould to eliminate the possibility of the device 10 being set into operation while the carrier is `free to pivot on the shaft. i

Other objects and advantages will become ap parent by reference tothe specication and the accompanying drawings, in which: l Fig. 1 is a verticalV section of the casting device embodying one form of the invention. 1 Fig. 2 is a detail vertical section of a part of the device. as may be taken substantially on the section line 2--2 of Fig. 1. 20

Fig. 3 is a plan section of the device, as taken substantially on the section line 3-3 of Fig. 1.

Fig. 4 is a fragmentary plan view of the device,

as indicated by the arrow 4 in Fig. 1. l Fig. 5 is a fragmentary sectional view of the 25.

upper portion of the device similar to Fig. l, showing some parts in side elevation and showing other parts in changed position.

Fig. 6 is a detail section taken substantially on the section line 6 -6 of Fig. 5. i 30 Fig. 7 is an enlarged detail of certain parts as' substantiallyseen in Fig. l, certain parts shown in side elevation.

Fig. 8 is a vertical section of Fig. 7. as taken substantially on the section line 8 8 of Fig. 7. 35 I Fig. 9 is a fragmentary view of certain parts as substantially seen in Fig. 5, but illustrating a mould of a form differing from that seen in Fig. 5.

Fig.'10 is a sectional detail taken substantially on the section line Ill-l0 of Fig. 9. 40

Fig. 11 is a fragmentary perspective o'f certain cooperating parts of the device. v,

The casting device, Ias illustrated, includes an upright cylindrical housing I having upper and lowercompartments v2 v'and 3, respectively.y sepa- 45 rated by a disc-like partition 4. The partition 4 rests upon an annular ledge 5 within the housing and is secured in place thereon by means of screws 6 threaded in the base `1 of the housing.v The housing also includesa disc-like cover 8 which is hinged on the housing, as at 9. A pair of stops lll may be provided on the housingat the hinged connection tov be engaged by the edgey of the cover to hold the cover in an open position. u

Arranged within the lower compartment 3 and mounted on the base 1, is an electric motor II having a vertically disposed driving shaft I2 arranged central with the housing and projecting through a bearing aperture I4 in the partition to extend into the upper compartment 2.

An electrical circuit connection is provided on the housing for the motor. Said connection comprises a connector of conventional design including a terminal block I5, of insulating material, mounted in an aperture in the wall of the housing, and having spaced terminal pins I6 and I1 connected with the terminals IB and IS of the motor through conductors 20 and 2 I, respectively. Included in the conductor 20 is a switch, of conventional design, as seen at 22, mounted in an aperture in the wall of the housing for controlling energization of the motor.

Disposed within the upper compartment 2 and mounted on the shaft I2, to rotate therewith, is a mould carrier 25. In accordance with certain objects of the invention, the carrier mounts a mould at one side of the axis of the shaft and counterbalancing means therefor at the side of said axis opposite the mould. 'Ihe carrier is also mounted on the motor shaft for `pivotal movement in a vertical plane about a horizontal axis intersecting the axis of the shaft so that the mould thereon may be weighed against the counterbalancing` means,l with releasable holding means being provided for normally holding the carrier in its balanced position on the shaft during the casting operation, as will be hereinafter more fully described. The mould carrier comprises a normally horizontal arm portion 26 extending from one side of the shaft I2 and having the mould counter-balancing means supported thereon.

The mould counter-balancing means includes a pair of weights 21 and 2l of different sizes, each having a depending screw formation 29 adapted to be received lin one of a series of threaded apertures 30 in the arm portion 26 and spaced therealong to enable adjustment of the weights on the arm.

The mould carrier 25 also includes a mouldsupporting arm portion 3| arranged on the side of the shaft I2 opposite the arm portion 26. The arm portion II comprises a rod bent in the form of an open rectangular; frame having horizontally disposed side-rod portions 32 joined at their outer ends by a transverse end-rod portion 33. The side-rod portions 32 continue at their inner ends into converging portions 34 having ends soldered or otherwise xedly secured within apertures in the sides of the arm portion 26.

Detachably mounted within the frame of the arm portion II is a mould-positioning member, or mould adaptor 35, to position a mould of a. certain shape, as for instance a box-shaped mould seen in Figs. 1 and 2. Said mould adaptor 35 comprises a metallic strip bent in the form of a channel-section or trough having a bottom portion 36 and upright sides 31 provided with turned-over or hooked top edges 38 adapted to be hooked over the side-rod portions 32 of the arm portion 3|. The member 35 cooperates with the frame of the arm portion JI to form a basket or pocket adapted to receive and position a boxlike mould 39 for producing such large castings as bridges or dentures, or the like.

The mould I9 is clamped in position in the mould adaptor 15 by a clamping member 40.. The member 4I is in the form of a lever comprising a spring strip having a loop formation 4I at one end formed about one of the side-rod portions of the mould carrier to provide a pivotal connection therewith. From its pivotal connection, the clamping member 4I) continues over the mould and terminates at its free end in a hook formation 42 adapted to be hooked over the other side-rod portion of the mould carrier, and being arranged to cause the clamping lever to have pressure engagement with the top of the mould. Thus the clamping lever'4IJ serves to hold both the mould and its adaptor 36 in position on the mould carrier. The hooked edges of the sides of the mould adaptor 35 are recessed at their mid portions, as at 43, to receive the hook and pivotal formations of the clamping lever 40, and to permit detachment of the mould adaptor from the mould carrier when the clamping lever is released from the mould.

The mould is composed of a hardened plastic substance, such as plaster, incased within an open-ended rectangular casing 45 of sheet metal. The mould has an'outwardly flared inlet opening 46 directed toward the axis of the motor shaft I2 for receiving the molten casting medium directed therein by centrifugal force by directing means, arranged on the motor shaft, as the carrier is rotated by the motor at a constant high rate of speed.

The directing means includes a cup-shaped member or vessel 41 disposed coaxial with and detachably mounted upon the top end of the motor shaft I2. The vessel 41 has a spout-like outlet 41a at its bottom arranged to extend within the inlet of the mould central therewith.

The vessel is composed of a plastic substance, such as plaster, and is so formed internally that as the molten medium or gold is supplied therein, by ladling means arranged on the cover 8, the gold will be forcibly directed or deflected downward in the vessel toward its outlet, and then directed outward into the mould by centrifugal force within the shortest possible time while the carrier may be rotating at a constant high rate of speed in a clockwise direction, as viewed in plan. By so forcibly directing the molten gold into the mould, the casting produced will have uniformity of hardness. To this end, as best seen in Figs. 1, 3, 7 and 8, the vessel 41 is formed with a tapered bore 4B having side-wall portions flared outwardly and downwardly to the bottom of the vessel. The vessel also has a spiroconically-shaped bottom 49 having a spirally formed side-wall portion 50 tapering upward from the side-wall of the vessel to a point of the aXis of the vessel and forming, with the wall portions of the bore, a spirally extending V-shaped groove or channel-way 5I in the bottom of the vessel terminating at its lowest point in register with the outlet of the vessel. At the outlet passage of the vessel the groove 5I is provided with an end-wall 52 extending radially of the axis of the vessel in register with a side-Wall of the outlet and slanting upward and forward in the direction of travel or rotation of the vessel to further insure deflection of the molten gold into the outlet of the vessel.

For detachably mounting the vessel 41 on the motor shaft I2, so that a damaged vessel may be quickly replaced, the vesselis positioned snugly Within a cup-shaped positioning member 5l which in turn is detachably mounted on the top end of the motor shaft. The positioning member 53 has a vertical slot 54 in its side-wall to receive and'm'sition the spout outlet of the vessel.

in register with the inlet of the mould. For detachably mounting thepositioning member 53 on the motor shaft, said member is provided with a sleeve portion or socket formation 55 depending centrally from its-bottom4 and adapted to be. snugly received on the top end of the motor shaft I2. The member 53 is keyed to the shaft |2 to rotatetherewith byhaving its sleeve portion 55 provided with I opposed downwardly extending slots 58 adaptedhto'receive a` pin 51 which extends horizontally through the motor shaft so as to intersect theaxis thereof. i

In accordance with .the invention, the mould carrier isfulcrumed upon the pin 51 for its pivotal movement, but is arranged to be normally engaged by the sleeve portion and held thereby in a .fixed position with respect to the motor and 11the carrier arm portion 26 has its inner end provided with a circular opening 58 which is largerin diameter than the motor shaft and through whichbpening the shaft extends, with the pin 51 having its ends rotatably received within bearing apertures 59 provided in the arm portion at opposite sides of the opening. When the sleeve portion 55 of the positioning member 53 is received on the motor shaft it is adapted to snugly iit within the opening 58 of the arm portion 26, whereby the carrier will be rmly held by said sleeve portion in a xed position .with respect to the motor shaft as it rotates therewith. When the sleeve portion 55 is removed from the opening 58, the shaft being freely received within said opening will permit the carrier 25 to pivot on the pin 51 for the purpose of enabling an operator to weigh the mould on the carrier against the counterweights 21 and 28, in deter- Vmining the proper adjustment of the counterweights on the arm portion 26 prior to the casting operation.

The ladling means comprises a cupped ladle 60, composed of a suitable plastic substance, detachably mounted upon the ladle carrier 6| which is pivotally mounted on the cover 8, as at 62, and

insure proper direction of the metal into the vessel. To this end, the outer end portion 86 of the passage of the spout 64 extends at right angles to the axis of the ladle, and the inner portion 61 of said passage curves upward as it continues into the ladle. The inner portion 61 of the passage of the spout forms a baille wall or Weir formation 68 between the spout and the interior of the ladle, with the Weir being so arranged under the upper portion 69 of the cupped wall of the ladle that, as the ladle is initially tilted, the molten metal in the ladle will be deected over the weir and against said upper wall portion with such force as to cause suflicient retardation in the rate of flow of the metal to ,permit the ladle toapproach its finally tilted yposition before the metal will ow from the passage 68 into the vessel 41.

The ladle carrier 6| is in the form of a troughshaped member having a flat bottom '1D provided with upwardly converging side-walls 1| and an end-wall 12 forming a dovetailed trough having one end open. The ladle is formed with upwardly tapering or converging outer sides 13 adapted to snugly fit within the trough or carrier," with the spout of the ladle projecting through an aperture 14 in the end-wall of the trough- Thus the ladlemay be removed from the open-end of the trough and replacedquickly'in the event the ladle bel- .comes damaged. The ladle carrier may be provided with a handle 15,-which may extend from the open-end of the carrier and rest upon the cover of the housing' to support the ladle 'inits upright position.

The invention also contemplates 'providing mould adaptors for the mould carrier that may accommodate moulds having shapes differing from that of the mould previously described. To accomplish this, as seen in Figs. 9 and 10, a channel-shaped mould carrier 18 is provided, being formed of sheet metal and including a bottom 11 and sides 18 provided with hooked top edges 19, similar to the mould carrier or adaptor 35, to be hooked over the side-rod portions 32 of the mould carrier. The bottom portion 11 of the adaptor 16 'is formed with an arcuately shaped depression-or recess 80 extending longitudinally from about the mid-section of the bottom, and within which recess va cylindrically shaped mould 8| is adapted to be recel'r d and held in position in cooperative relatif/6th the vessel 41 by the clamping lever 40.-?? e mould 8| is of the type employed Yfor producing such small castings as inlays, or the like, for teeth'. Said mould 8| may be composed of a plastic substance, such as plaster, incased within a cylindrical casing 82 and having an inlet passage 83 adapted to register with the outlet of the vessel 41 when the mould is clamped in position on the adaptor 16. Brake means is provided for stopping rotation of the mould carrier as it rotates by force of momentum afterrthe motor is turned oi. Said brake means includes a brake rod 84 disposed radially of the motor shaft and below the partition 4, and being reciprocably mounted in spaced bearings 85 depending from the partition. On the inner-end of the brake rod is secured a brake shoe 86 adapted to engage a brake wheel 81 secured on the motor shaft |2. The brake shoe is resiliently held against one of the bearings 85 out of engagement with the brake wheel by a coil spring 88 which surrounds the brake rod and is interposed under compression between a collar 89 on the outer end of the rod and the adjacent bearing 85. For actuating the brake rod to cause application of the brake shoe to the brake wheel. the collar 89 has a threaded bore receiving the threaded stem 90 of a knob 9|. The knob is disposed exteriorly of the housing with its stem 90 passing freely through an opening 92 in the wall of the housing. Thus the knob may be detached from the brake rod to enable removal of the partition from the housing. Also the brake shoe may have its brake wheel engaging-surface 93 formed arcuately in accordance with the periphery of the wheel. A general explanation of the operation of th casting device will now be dwelt upon.

With the cover 8 in open position, and with the motor turned off, the vessel 41 with its positioning member 53 is removed from the shaft I2 to permit the mould carrier to pivot on the pin 51 extending through the shaft. The mould selected for the casting operation is then clamped on its adaptor and. the Weights 21 and 28 are adjusted until the mould carrier is properly balanced on the pin 51. The vessel 41 and its member 53 are then placed on the motor shaft to lock the carrier in fixed connection therewith and the cover 8 is closed. With the ladle in upright position, the proper amount of metal is placed in the ladle and then melted by any suitable means such as an acetylene torch, or the like. While the metal is being heated, the motor is turned on to make sure that the mould carrier will be rotating at a. constant high rate of speed during the casting operation. When the metal has reached the proper melting point, the ladle is tilted to direct the molten metal into the vessel 41 to complete the casting .operation as heretofore described more in detail.

Having thus described my invention, I claim:

1. In a casting device of the class described, a. housing, a mould mounted to rotate about an axis within the housing, a vessel for receiving a molten casting medium arranged central with the axis, said vessel being in passage communication with the mould and having its top open-end registering with a supply opening in the top of the housing, and a ladle mounte'd on the exterior of the housing for limited movement from an upright position to a tilted position in supplying relation with the opening in the housing. I

2. A ladle for a casting device of the class described, comprising aV side-wall provided with a discharge passage formed with an outer passage portion directed laterallyof the wall and an inner passage portion continuing angularly upward into the ladle and opening therein above the bottom thereof and forming therebetween a Weir formation between the interior of the ladle and the outer passage portion, and said sidewall having an upper deflecting Wall portion continuing angularly upward and inward of the ladle and over the Weir formation from the upper wall of the inner passage portion.

BERT L. HOOPER.

' CERTIFICATI- T.' OF CORRECTION. Patent No. 2,192,0t5. February 27, 19m.

BERT L. HOOPER.A

It is 'hereby certified that error appears in the printed specification ofthe above numbered patent requiring correction as follows: Page, fizrsl:l column, -lins 18 after' "motor" insert shaft. To this end, as best seeri in Figs. 7, 8; and that the said Letter-s Patent shouldbe readwith this cor--v rection therein that the same may conform to the record of the case in the Patent Office. v

Signed and sealed this 2nd day of April, A; D. 19h0.

Henry Van Ar'sdale, Seal) Acting Connnis'sionef of Patents.

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