US2037618A - Motor driven casting machine - Google Patents

Description

April 1936. w. l. CARPENTER MOTOR D RIVEN, CASTING MACHINE Filed May 31, 1934 3 Shets-Sheet l "@Zsier I. Cur 0611i] April 14, 1936. w. l. CARPENTER MOTOR DRIVEN CASTING MACHINE 5 Sheets-Sheet 2 Filed May 51, 1954 April 1936 w. I. CARPENTER MOTOR DRIVEN CASTING MACHINE Filed May 31, 1934 3 Sheets-Sheet 3 a 144) C YVLCW/ 'Wesi er I. Oar- 0 m structed in a manner as Patented Apr. 14, 1936 PATENT OFFICE,

, 2,031,011: moron. mnvan cas'rmo mourns Web ter 1. carpenteramut. vs." Application May :1, 1934, Serial No. 128,454 1 claims. (01. 22-654) UNITED. TATES This invention relates to a centrifugal casting machine designed primarily for use in the making of metallic dental castings, but it is to be understood that a machine, in accordance with this invention may be employed in any connection for which it is found applicable, and has for its object to provide a machine of the class referred to conhereinafter set forth whereby the applied force thereto will initially create a lifting action upon a casting element carrying a body of molten. metal for throwing the latter down into the mold on the first half of the first revolution of the machine and immediately following the throwing of the metal into the mold building up a centrifugal force sufficient to retain the metal in the mold during the second half of said first revolution and during successive revolutions of the machine until the metal has cooled sufliciently to retainshape. I

Centrifugal force is a delayed force, it takestime to build it up and for that reason it is not dependable to force'the metal in the mold while it is very hot. It is true that centrifugal force is used in some forms of casting machines to force the molten metal into the mold, but it is recog nized also that the metal has slightly cooled before the centrifugal force has built up sumciently to force the metal into the 'mold, and for this reason it is found that when using a specified size sprue opening to mold that the molten metal, having slightly cooled while waiting for the centrifugal force to build up, does not flow as freely, thereby preventing as much molten metal flowing through the specified sprue opening as would be possible, co d the molten metal be forced into the mold ediately while it is very hot, and in a very high state of fluidity. It is further recognized, that molten metal in; a very high state of fluidity or while very hot, will adapt to the shape, and crevices of the mold more perfectly, than it is possible to do when ithas slightly cooled, yet though, still in a fluid state, is not as mobile as a very hot freely flowing molten metal. It is the primary object oi! this invention to immediately on the start of the machine to throw a very hot freely flowing molten metal into the mold to attain the advantage as aforesaid.

A further object of the invention is to provide a construction of casting machine whereby molten metal will be thrown immediately into a mold on the starting of the machine. resulting in more molten metal being forced into the mold through a specified size sprue opening than would be the case should the metal be allowed to slightly 0001. This has a practical value to the dentist,

v in a very fluid state or the user of the machine. It means that the one using the machine does not have to use a large number of sprue openings to the mold to accommodate the passage of the molten metal. Why, because the machine acts to throw the 5 molten metal immediately into the'mold while the metal'is in a very fluid state.-

A further object of the invention is to provide a centrifugal casting machine for throwing metal into a mold, whereby the 1 very hot fluid state metal will adapt itself to all nooks and crannies of the mold, thereby making a casting with sharp detail, that is a perfect casting. It is a well known fact that when the molten I metal has seriously cooled, that it does not, in a rather stiffened condition, flowto all nooks and crannies of the mold. Castings,.therefore, have no detail, and the edges all are round, without sharp detail.

A further object of the invention is to provide a motor driven centrifugal casting machine with mean'sto prevent a too fast starting thereof, to

overcome the throwing of the molten metal from off of the top of the casting element and waste it.

A further object of the invention is toprovide a centrifugal casting machine which will permit of the metal, being heated in the end of .the casting element, itself. This keeps the said element hot while the metal is being melted. When the metal is melted, the machine is started, the metal does not have to travel through the air from a crucible to the casting element and thereby, cool off seriously, but it being already on the top of the casting element, when themachine starts, is thrown immediately into the mold 5 through the sprue opening leading-to the latter.

To the above ends essentially, and to others which may hereinafterv appear, the invention consists of such parts, and such combination of parts which fall within the scope of the invention as claimed.

In the drawings: 0

Figure l is a side elevation of the machine and further illustrating in dotted lines one position of the ha ger shaft during the operation 45.

thereof, I v

Figure 2 is a section on line 2-2 Figure 1. v Figure 3 is a section on line 3-3, Figure 2, Figure 4 is a detail sectionillustrating the coupling means between-the operating and motor shaft,

[Figure 5 is a fragmentary iri side elevation and in section of the upper portion of the machine,

Figure 6 is an elevation partlyixf'section leoking towards one end of the hanger shaft, and

Figure '7 is a fragmentary in side elevation of the lower portion of the machine.

The machine includes a windable spring motor of any suitable type, not shown and which will have its power spring housed within the intermediate portion I of a base 8. The motor will be of that type including a power transmitting shaft 9 extended upwardly from the top portion I8 of base 8. Preferably the form of spring motor employed will be similar to that disclosed by Patent 1,195,803, August 22, 1916. It is to be understood however that any suitable motor capable of being installed in the base 8 for driving the operating shaft of the machine may form a part of the latter. The base 8 is permanently disposed at an inclination with respect, tothe support, not shown, upon which it is mounted and anchored to. The lower portion II of base 8 is formed with an outwardly directed flat annular flange I2 having apertures for the passage of holdfast devices I3 for the purpose of flxedly securing the base to its support. tions I, I8 and II of base 8 are disposed at an inclination to flange I2. The top edge of portion I of base 8 is disposed at an inclination. The portion I I of base 8 is flared at its lower part in one direction sidewise, as at I4. The base 8 is tubular. The portion 1 of the base is of uniform diameter. The portion I8 of the base tapers. The portion II of the base 8 has a lengthwise offset web I5 which merges into the bottom of portion I and which provides a guide channel for a latching rod I6. The purpose of the latter will be hereinafter referred to. The portion I has an opening IT. The rod I6 is of a length to extend from the lower part of portion I I up through opening I1 and beyond the top of portion I. The rod which extends outwardly through a slot I9 formed in the web I5. The finger piece I8 facilitates the shifting of rod I6 to and from latching position. The rod I6 is disposed at an inclination similar to that of base 8.

The shaft 9 is of that type capable of being rotated in opposite directions. It is rotated in an anti-clockwise direction manually to wind up the power spring of the motor. It is rotated in a clockwise direction by the power spring of the motor and then functions as a power transmitting shaft. The shaft 9 has its upper end portion 28 of enlarged outer diameter with'respect to that portion of shaft 9 from which it extends. The shaft 9 is disposed at an inclination similar tothat of base 8. The portion 28 at its inner end is formed with an outwardly directed annular flange 2 I. The'portion 28' is bifurcated and with the furcation, indicated at 22 opening at the outer end thereof. The portion 28 has peripheral threads designated 23, extending from its outer end to a point in proximity to its transverse median.

There is associated with shaft 9 a weighting means in the form of a fly wheel 25 consisting of a circular disc 26 of materially greater diameter than the portion I of base 8. The disc 26 has an axial bore having its wall of two different diameters. Thepart of largest diameter is designated 21 and the other at 28. The junction of the two diameters of the wall of the bore forms a seat or shoulder 29. The part 21 is of less length than part 28 and is arranged at the upper portion of the disc. The latter is formed with a groove 38 which extends from seat 29 and terminates at a point adjacent the inner face of the The por- I6 carries a finger piece I8 disc. The groove 38 opens at seat 29 and into the part 28 of the bore. The disc 28 is positioned in encompassing relation with respect to portion 28 of shaft 9. The disc 26 is coupled to shaft 9 by a key 3I having its upper portion 32 of reduced width with respect to its lower portion 33. The key 3| is seated upon the base wall of the furcation 22 and has its wider portion 33 extend into groove 38 whereby disc 26 will be coupled with shaft 9 to bodily rotate with the latter. The purpose of reducing the upper portion 32 of key 3| will be hereinafter referred to.

The machine includes a horizontally disposed hanger shaft 34 and an inclined operating shaft 35 acting upon shaft 34 to cause it to travel in an inclined circular path. The shaft 35 is permanently inclined to the vertical. The shaft 34 is disposed at an oblique angle to the shaft 35. The latter has its lower portion peripherally threaded as at 36 for engagement by an internally threaded coupling sleeve 31. The internal threads 24 of the latter also engage with the threads 23, of the portion 28 of shaft 9 whereby the latter is coupled to shaft 35 to provide for the latter extending at the same inclination as that of base 8 and to provide for shafts 9 and 35 operating in unison. The sleeve 31 extends into the part 2? of the wall' of the bore of disc 25 and bears against seat 29 whereby the inner end of sleeve 31 will coact with seat 29 and flange 2| for holding disc 26 in a manner to prevent it shifting lengthwise of portion 28 of shaft 9. The reducedupper portion 32 of key 3l functions to provide a clearance for the threads on the inner face of sleeve 31. Formed integral with the upper end of the shaft 35 is an internally threaded sleeve 38 which is disposed at an angle with respect to the axis of shaft 35, and extends from one end to the other at a slight upward inclination with respect to the upper end of shaft 35. The length of sleeve 38 is greater than the diameter of and extends forwardly and rearwardly beyond opposed sides of shaft 35.

The shaft 34 extends through and projects beyond each end of sleeve 38. The shaft 34 is peripherally threaded intermediate its ends, as at 39 for engagement with the threads 39 of sleeve 38. The shaft 34 is adjustable lengthwise of sleeve 38 and has one end portion formed with an integral counterweight 48. The other end portion H of shaft 34 has peripheral threads 43 and a concave recess 42 which is formed in the end edge 44 of portion 4|. At the inner end of the threads 43 shaft 34 is provided with a peripheral shoulder 45. The shaft 34 extends at the same pitch as that of sleeve 38.

Extended from the end edge 44 of shaft 34 is a suspension member 45 for a carrier or basket 41 for a casting element 48. The member 46 consists of a stem 48 provided at its upper end with a spherical enlargement 58 which seats in the recess 42. The lower end of stem 49 is reduced,

as at 58' and formed with an aperture 5|. Threadedly engaged with the threads 43 is a retaining collar 52 formed at its outer end with an inwardly arranged annular flange 53 having its rear face 54curved for seating against the eni largement 58. The latter, recess 42 and the flange 53 coact to provide a universal joint connection between shaft 34 and member 4 Carried on a pivot 55 disposed at right angles to the axis of shaft 34 is a torsionally twisted hanger 58 for the carrier 41. The upper portion of hanger 56 is in the-form of a yoke 51 having its arms formed with aligning openings 58. ,The

stem 48 is positionedbe- 51 with the aperture lower end In" of the tween the arms of yoke aligning with the openings 58. The pivot 55' exthe openings 58.

carries a retaining nut 58 therefor. The lower portion of hanger 56 is designated 68 and formed ,with an opening 6! disposed at right angles to The carrier 41 includes a bottom plate 82 uponwhich is seatcd'the casting element 48 and a pair of oppositely disposed arms 63, 64 formed with portions 65, 66 respectively terminating in vertically disposed parallel spaced portions 61, 68 respectively formed with parallel openings 68. The carrier 41 also includes a support 18 in the form of an annulus which is arranged between and securedto the arms 65, 86 between the transverse medians of said arms and plate62. The lower portion 68 of hanger 56 is arranged between the portions 61, 68 of the arms of the carrier and has its opening 6! align with the openings 68. Extending through the aligning openings 6|, 6.9 is a pivot bolt II carry a securing nut 12. The support 18- is adapted to have removably mounted therein a balance member 13 in the form of an annulus and which also functions as a retainer for the element 48. The inner edge of member 13 is oppositely beveled as'at 14'.

The casting element 48 includes a casting ring I8, an investment 19, a molding chamber 88, and a sprue opening 8| leading to chamber 88. One end of investment 19-is formed with an opening 84 the base thereof formed with a cavity 82 for receiving the body of metal 83 to be melted. The sprue opening 8| communicates with-the cavity'82. Thewa-ll of opening 84 is terraced as at 85.

As is well known in all motor driven machines they areopen to the objection of too quick starting, now to overcome the objection it is necessary to have the machine in accordance with this invention so constructed to overcome that too quick starting. In connection with this invention it is accomplished by adding weight in the form of the fly wheel 25 and also rigidly fixing the counterbalance 48 to the shaft 38 which gives added weight to the fly wheel 25. i It is recognized that 7 released, the greater mill is therefore, the fly wheel structure absorbs this iniof the casting element.

when the spring of a spring motor is wound up that the pull forceof the spring increases as it is wound up. Consequently when the spring is right from the start,

tial strong pull of the spring and prevents a too fast starting of the machine, which otherwise would throw the molten metal from off of the top The fly wheel 25 not only acts to absorb the initial strong pull of the motor spring, but also constitutes a momentum for a shaft 8. The wheel 25 is latched from movement by the rod l6. being extended into a socket 86 (Figure 2) formed in the lower face of the disc 25. The fly wheel 25 is disposed in an inclined plane parallel to that of the edge of the upper end of portion of base 8.

' The machine permits of the metal being heated in one end of the casting element itself by a blow pipe, and this keeps the said element hot while the metal is being. melted. When the metal is melted the machine \metal travels immediately into the molding is started and the molten chamber through the sprue opening. The conthrows the very struction ofthe machine will givea lift action on the starting thereof, before any centrifugal.

had time'to build up and such action hot molten'metal force has until the metal The arranging of sleeve 38 in the manner as shown prevents the carrier suspended from shaftv 34 hitting the support to which base 8 is attached, the metal or other objects on the support in proximity to the machine during therevolving of shaft 34 and which wouldnot be the case if the ends 38 of sleeve 38 were parallel .to the axis of shaft 35. a

The shaft 34 is adjustable lengthwise of the one end thereof is moved away from and its other end moved towards the center of gravity resulting without the necessity of ajusting the counterbalance lengthwise of said shaft.

, When the machine is operated, the shaft 34 sweeps out two conical paths with the apices of the cones adjacent. The axis of the two cones blow pipe employed for heating the.

' sleeve to balanced position and when so adjusted being common to each other and being. one and the same as the axis of the shaft 35.v Upon initially starting the machine the shaft 34 not only starts to course in a circle but as the shaft 34 travels in a slightly upward direction, the carrier 41 swings outwardly and the shaft 34 tends to lift the carrier 41 until its long axis approaches a point approximately at a right angle to the axis of shaft 34, and therefore the centrifugal force does not whip the carrier up to position as aforesaid outward and lifting action applied to the machine speeds up. During the the carrier 41, the latter is at the same time being carried in a circular path, the axis of which is parallel and one and the same as the axis of shaft 35. As the latter is permanently inclined to the vertical and the shaft 34 disposed at an oblique angle to shaft 34 no two points on the shaft 34 travel in the same path, but each individual point of shaft 34 travels in a circular path, the axis of which is the axis of shaft 35.

The fly wheel not tarding function referred to, but also acts to develop a gyroscopic' force that steadies the superstructure of the machine should the counterbalance and the carrier be slightly out of balance.

' .What 'I claim is:-

1. In a centrifugal casting machine, an upstanding rotatable operating shaft permanently inclined to the vertical, a revoluble hanger shaft having a fixed counterbalance at one end and universally suspended from its other end a casttation of said. operating shaft a lifting action will 7 shaft to immediatelybe impartedto the hanger throw the molten metal into the casting element and on continuation of the rotation of the, operating shaft centrifugal force will be built up 'to maintain the metal within said element.

2. In a centrifugal casting machine, an upstanding rotatable operating shaft permanently inclined to the vertical, a revoluble hanger shaft only provides for the rehaving a fixed counterbalance at one end and universally suspended from its other end a casting element arranged to carry a body of molten metal, said hanger shaft being connected intermediate its ends to, operated from and being permanently disposed at an oblique angle to said operating shaftwhereby on the start of each rotation of said operating shaft a lifting action will be imparted to the hanger shaft to immediately throw the molten metal into the casting element and on continuation of the rotation of the operating shaft centrifugal force will be built up to maintain the metal within said element, a motor driven shaft permanently inclined to the vertical and having its axis corresponding to the axis of saidv operating shaft, and means for connecting said operating and driven shafts in endwise opposed relation.

3. In a centrifugal casting machine, an upstanding rotatable operating shaft permanently inclined to the vertical, a revoluble hanger shaft having universally suspended fmm one end thereof a casting element arranged to carry a body of molten metal, said-hanger shaft being connected intermediate its ends to, operated from and being permanently disposed at an oblique angle to said operating shaft whereby on the start of each rotation of said operating shaft a lifting action will be imparted to the hanger shaft to immediately throw the molten metal into the casting element and on continuation of the rotation of the operating shaft centrifugal force will be built up to maintain the metal within said element, a motor driven shaft perma-.

nently inclined to the vertical and having its axis corresponding to the axis of said operating shaft, means for connecting said operating and driving shafts in endwise opposed relation, 9. combined absorbing and momentum means of disc-like form connected to, bodily moving with and disposed concentrically to the axis of said driven shaft for retarding quick starting of said operating shaft, and 'a coupling connecting the operating shaft to the driven shaft including means to prevent the disc shifting lengthwise of the driven shaft, said .4. In a centrifugal casting machine, a revoluble hanger shaft provided with a fixed counterweight at one end, a suspension means for a casting element carrier formed of an inner and an outer section pivotally connected together, said shaft at its other end and said inner section having coacting parts forming a ball and socket joint, means for pivotally connecting the outer couplingmeans disposed con- .centrically to the axes of said shafts.

for revolving the hanger shaft, and means for connecting said hanger shaft to the upper end of said operating shaft at anoblique angle.

5. In a centrifugal casting machine, a suspended carrier for-a casting element arranged to support a body of molten metal at its top, and a bodily rotatable structure including an operating shaft and a hangershaft connected upon the upper end of the operating shaft, means for suspending the carrier from: said hanger shaft, the said operatingshaft being permanently disposed at an inclination to the vertical and said hanger shaft being permanently disposed at an oblique angle to-the operating shaft to provide during each rotation of the operating shaft for' the hanger shaft applying a lifting action on the carrier to immediately throw the'molten metal into the casting element and for applying centrifugal force to the said carrier immediately following the lifting action to maintain the metal within said element.

6. In a centrifugal casting machine a rotatable operating shaft permanently inclined to the vertical, a revoluble hanger shaft operated from said operating shaft, means for suspending a casting element from the hanger shaft, and means at the upper end of the operating shaft for connecting the hanger shaft intermediate its ends to and for permanently maintaining the hanger shaft at an oblique angle to said operating shaft.

7. In a centrifugal casting machine aweightcd rotatable operating shaft permanently inclined to the vertical, a revoluble hanger shaft operated from said operating shaft and having a fixed counterweight at one end and a recess at its other end, a suspension formed of an inner and an outer section pivotally connected together at one end, said inner section .being formed with a globular enlargement at its other end arranged in said recess, means for loosely connecting the enlargement to the hanger shaft in extended relation thereto, means at the other end of the outer section of the suspension and disposed at right angles to the pivot between said sections of the suspension for pivotally connecting a casting element carrier to said suspension, and means at theupper end of the operating shaft for connecting the hanger shaft intermediate its ends, to the operating shaft and for permanently maintaining the hanger shaft at an oblique angle to saidioperating shaft. WEBSTER I. CARPENTER.

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