US1917872A - Centrifugal casting machine - Google Patents

Description

' Juiy 11, 1933.- D. J. CAMPBELL 1,917,872

CENTRIFUGAL CASTING MACHINE Filed Nov. 9, 1951 3 Sheets-Sheet I I l I Ill: 9 L 7 Yb 55 ACW Qmme g Donakl' c5. Cgmpbe \nuenToY Jufiy 1 1, 1933.

D. J. CAMPBELL E HZWZ CENTRIFUGAL CASTING MACHINE Filed Nov. 9, 1931 s Sheets-Sheet 2 Donaud c). Cam mL Tiome 5 muen Im' y 1933- D. J. CAMPBELL CENTRIFUGAL CASTING MACHINE 5 Sheets$heet 5 Filed Nov. 9, 1931 operation Patented July 11, 1933 UNITED STATES PATENT OFFICE DONALD J'. CAMPBELL, OF MUSKEGON, MICHIGAN, ASSIGNOR TO CAMPBELL, & CANNON FOUNDRY COMPANY, OF MUSKEGON, MICHIGAN, A CORPORATION OF MICHIGAN CENTBIFUGAL CASTING Application filed November 9, 1931. Serial No. 573,949.

This invention relates to a centrifugal casting machine, the purpose of which is to deposit molten metal at the inner side of a revolving drum and integrally fuse the molten metal with the material of the drum as disclosed in my pending application, Ser. No. 512,792, relatin to a Process of centrifugal castings, filed lfebruary 2nd, 1931, and to produce specifically a double width drum having an outer shell of rolled or pressed metal and an inner integrallyfused band of cast iron which, after the process has been completed, may be divided between its edges to make two flanges for automobile brake drums as shown in my' pending application Ser. No. 544,350 for Composite drum, filed June 15th, 1931.

'The present invention is directed to an apparatus or machine for effectively carrying out the process mentioned and for producing the devices illustrated and described in the last mentioned application. The invention while of greatest use in connection with brake drums is not in any sense limited to such devices alone.

It is an object and purpose of the present invention to provide a practical machine and apparatus for casting and fusing cast metal bands at the inner side of surrounding rolled or pressed metal drums, wherein speed of in inserting the rolled or pressed drums and in ejecting the composite pressed drum with cast metal bands fused at theinner side thereof is attained.

It is a further object and purpose of the invention to provide the machine with a simple and effective mechanism for depositing or pouring the cast metal against the inner side of the outer rolled or pressed metal drum in a measured amount so as to provide the necessary thickness and yet not give too great a thickness of cast metal.

Other objects and purposes are to provide practical and'efiective means for the ready and easy insertion of the outer drum in a fixture and the clamping of the same against undesired movement while cast metal depositing takes place and to free the composite drum after it has been produced; and to provide various other practical and novel features of construction for effectively attaining the ends stated.

An understanding of the invention may be had from the following description taken in connection with the accompanying drawings, in which, I

Fig. 1 is a front elevation of a machine for lining pressed metal drums with inner" cast metal bands and fusing the same thereto.

2 is an end elevation thereof.

Fig. \3'is a fra entary plan View of one end of the mac ladle, turned to its outer filling position.

Fig. 4 is an enlarged central longitudinal sialction through the upper part of thema- 0 me.

- sheet metal drum into which the molten metal is poured and illustrating to pour the molten metal.

Fig. 6 is a vertical longitudinal section through the composite drum produced on'the machine.

Fig. 7 is a perspective view of the molten metal holding and pouring ladle. Fig. 8 is a fragmentary enlarged view lllustrating the manner in which the composite drum, after it has been produced, is released from the machine,and'

9 is a fragmentary plan and partial section showing one method by means of whlch the rotating fixture engaging head may be heated, if necessary.

Like reference characters refer to like parts in the different figures of the drawings.

In the construction shown, a support 1- is provided above and resting on which is a head 2 having two spaced apart upwardly extending housings 3 in which roller bearings 4 are mounted for the rotatable mounting of the ladle tipped ine showing the pouring a hollow shaft 5 which lies between and ex- The shaft 5 is adapted to be rotated at a relatively high speed, which speed in operation will range from 900 to 1800 R. P. M., depending upon the size and diameter of the drum being. processed. That is, a drum of large diameter will require slower rotation of the shaft 5 than will a smaller drum, and again, other factors such as the heat of the molten metal may enter in. For these and other reasons a rather wide range of speeds 1S necessary, the determination of which in each case lies largely with the skilled operator in charge of the machine. A gear 9 on the shaft 5 may be driven by an endless chain 10, which in turn passes around a drive gear 11 on the shaft of a variable speed electric motor 12 which is located conveniently andbetwecn the sides or lower part of base as shown in Fig. 1.

lVithin the hollow shaft 5 and extending the full length thereof and beyond the same at its ends is a tubular shaft 13. It is threaded at its outer end for the connection of a head 14 which is-located adjacent the inner end of the open head 6 previously described. At'the other end of the tubular shaft 13 is a ball bearing housing 15 carrying bearings 16 whereby the shaft 13 may freely rotate within the housing 15. Since considerable heat is generated during the operation of the device herein it may be desirable and even necessary in some instances to provide means for water or otherwise cooling the bearings thereof, said means notbeing shown in the drawings however as such is not an essential part of the instant invention.

A rod 17, connected at one end to the housing 15, extends therefrom in axial alincment with the tubular shaft 13 and carries a piston 18 mounted within a c linder 19. The cylinder 19 is cast integral with and extends from one end of a housing 20 which in turn is connected to the supporting head 2 of the machine, the housing 15-and parts of the shaft 13 and rod 17 extending lengthwise centrally of the housing 20 e The cylinder 19 is closed at both ends and has ports ateach end thereof through which compressed air or fluid may be entered or exhausted, using pipes 21 which connect at one end to the cylinder ports and at the other end to a valve housing 22 into which compressed air from a reservoir therefor is carried by an inlet pipe 23. A valve 24 manu-- ally operated by a handle 2 10, may be swung to two different positions to direct the compressed air to either end of the cylinder 19 and open the other end of the cylinder to the outside through an exhaust port 25' (see Fig. 8).

It is apparent from the foregoing construcpiston 18 may be selectlvely moved either to the forward position shown in Fig. 8 or to its back position shown in Fig. 4; and the tubular shaft 13, with the head 14 at its forward end, is moved from outer to inner position or vice versa depending upon the position to which the piston 18 is moved. In Fig. 8 the head 14 is shown at its outer position and in Fig. 4 at its innermost position. A rod 26 extends into the forward end of the tubular shaft 13 and for the major portion of its length, and bears against a coiled compressed spring 27 housed within the tubular shaft 13 and located between the end of the shaft 26 and a screw plug which closes the inner end of the tubular shaft. (Fig. 8). The front end of the rod 26 has a disk-like head 28 secured thereto with an annular groove 29 at the curved edges of the disk.

A separable and contractible drum holder xture is connected with theheads 14 and 28. The drum holding fixture is made up of a plurality of segments each having an inner are shaped side 30 with spaced grooves 31 therein, an outer tapering side 32, a front end 33 integrally connecting the front edges of the sides 30 and 32 and a rear end 34 connecting the same at their rear edges; and from the rear end of each of the segments a substantially trapezoidal shaped wing-35 extends radially inward and is formed at its inner end with a rounded head 36 to enter the annular groove 29 in the head 28 (Fig. 8). The space 37 enclosed by the sides 30 and 32 and ends 33 and 34 in each segment suitable heat insulating substance. In either case the dissipation of heat outward is very materially checkedso that when the pressed 37 may be cooled by air passing therethrough or by other suitable means.

From the segments thus described fingers are forced to closed position, as shown in Fig. 4, through the bearing of the tapered inner sides of the flange 7 against the tapered outer sides 32 of the foregoing it is apparent that this composlte member becomes, when closed, a true said segments. From of flange die to hold an article such as abrake drum, the shape and size of said die being determined b ments thereof. This form must be large enough to take care of the expansion of the heated the formation of the completed drum, as is explained more in detail elsewhere in this specification. From .008 to .012 per inch of diameter is usually allowed in the form for expansion, and for this reason a cold drum placed in the die has such clearance that it will hardly form sufiicient contact therewith to rotate. The allowance in the die for expansion of the drum must depend largely upon the temperature to which the drum is heated befoiaadnsertion forcasting, the higher the temperature the greater the expanslon.

A drum 41 of pressed or r\olled metal may be formed with spaced annular beads 42 and at the ends with inwardly turned annular lips 43. These drums are heated to a temperature of somewhere within the range of 1200 to 1500 Fahr. With the holding fixture in outer position, as in Fig. 8, the drum is inserted into the fixture and then by turning the handle 24a to, the position shown in Fig. 4 drawn into the head 6 and the fixture clamped against the drum, the beads 42 seating in the annular grooves "31 of the fixture segments. Although the segments of the inner form herein have been described as having annular grooves 31, it is apparent that the presence or absence of such grooves may depend largely upon the particular type and shape of drum being processed at the time, and for which the die has been prepared. A drum with a fiat outer surface will require no grooves in the form, and in fact, such would be useless, while a drum with one or more beads (Fig. 6) or other surface irregularities will work best with a die formed with corresponding indentations, the purpose in each case being to iiisure efiicient engagement between the drum and the .form.

It is likewise apparent that with the apparatus in drum receiving position, as in Fig. 8, there is no positive driving connection causing the shaft 13, head 14 and the fixture segments to rotate, but that as soon as the piston 8 is forced tothe outer end of cyhnder 19, as in Fig. 4, the fixture, being in firm frictional engagement with the inner sides 7 of head 6 and in further engagement at the back ofthe spider head 14 as at 14a, will rotate with said head 6. Likewise it is evident that on the contraction of the fixture against the the attached rod 26 are moved inwardly with a compression of the spring 27 which also acts to force the outer sides of the segments of the fixture into firm contact engagement the contact joints between the seg-' drum, which expansion 1s a factor in the fixture with the drum therein will be drum 41, head 28 andwith the inner sides of the flange 7, whereby rotation of the drum will be insured.

A supporting bracket 44 (Fig. 1) extends from one end of the support 1, carries the hood 8, and is utilized for mounting the ladle carrying arm 45 which at one end is formed 51 to the upturned end 45a of the arm 45. In

order to protect the outer shell thereof from burning through when filled with molten metal, the interior of the ladle 49 is lined with fireclay or other suitable refractory material.

The arm 45 has a branch 52 (Fig. 2) extending downwardly to which a vertical air cylinder 53 is pivotally connected. A piston rod 54, operated by the action of compressed air entering the lower end of the cylinder 53, extends from the upper end of the cylinder and is pivotally connected to other ears depending from the lower side ofthe ladle 49; whereby on upward movement of the rod 54 the ladle is tippedv from its horizontal position, shown in Fig. 2, to the pouring position shown in Fig. 5. Although the actuation of the piston 54, and more particularly the tilting of the ladle 49 in connection therewith, has been described as being accomplished by means of compressed air herein, it is apparent that this action may be effected in a number of different ways, as, for instance, by manually tilting the ladle, orby using fluid pressure means to do this, or for that matter by employing any suitable force to secure the desired result. The ladle at its upper edges on opposite sides is formed with depressions or notched recesses 55 and 56 (Fig. 7). The notch 55 governs the level of molten metal in the ladle when it is in its filled position as shown in Figs. 2 and 3, while the longer recesses at 56 governs the width of the stream of molten metal which flows from the ladle when it is tipped to pouring position.

Compressed air carried in a pipe 57 to and through a valve housing 58 and thence through a tube 59 may be entered into the lower portion of the cylinder 53 to elevate the rod 54 and tip the ladle, a valve in the valve housing 58 being utilized for control- *ling the How of air so as to tip the ladle gradually and cause the pouring to be uniform from the time the same begins until the ladle is completely tipped and all of the molten cast metal therein has been poured.

It is designed that the head 6 shall itself be initially heated and, if necessary, kept at the des red range of temperature by heat or, cold applied thereto as may be required. In

Fig. 9 is shown one way in WllICh said head may be heated, that is, by an electrical heating element 60 partly around the same. Similarly, a cooling unit may be utilized. In practice, at the beginning of the operation of the machine, the head may also be initially heated by a blow torch and thereafter reliance placed upon the escape of heat from theheated drums 41 and from the molten metal which is poured into said drums to maintain the head 6- at a desired working temperature. In this situation the radiation of heat through the space 37 is regulated as desired by utilizing a heat conducting material of the desired characteristics therein.

The shaft, 5 as shown in Fig. 4, may also be equipped with any suitable brake to stop its rotation and at 61 there is indicated a magnetic brake for such purpose.

lVith the drum holding fixture in its outer expanded position, as in Fig. 8, a drum 41, heated .to a temperature within the range of 1200 and 1500 Fahr. approximately, is placed within the open expanded segments of the fixture and the handle 24a turned from the position shown in Fig. 8 to that shown in Fig.4, whereupon the fixture with the drum in it are drawn to inner position as shown .in Fig, 4. In the meantime or at the same time the ladle 49 is filled with the molten cast iron. While such filling of the ladle is taking place the arm 45 on which the ladle is carried is swung to outer position shown in Fig.3. The molten cast iron, indicated at 62, fills the ladle until it overflows at the overflow notch. Arm 45 and the ladle are then swung through an arc of substantially 90 so as to bring the ladle partly within the drum carried by the contracting fixture described. The valve 58 is opened so as to permit the passage of a predetermined con-' tinuous quantity of compressed air to cylinder 53 whereupon the ladle is progressively tipped and molten iron flows in a thin sheet, indicated at 63, over the outlet lip at the bottom of the recess 56 and deposits upon the rapidly turning drum 41, which drum is rotated at a suitable speed as explained previously herein. In practice it takes anywhere from three to ten seconds to empty the ladle and during this time the drum will have turned through many revolutions. If, for example, the molten cast iron is deposited in three seconds the drum at 1100 R. P. M. will have turned through fifty-five revolutions; and if five seconds are consumed the drum will have turned through more than ninety revolutions.

After the iron from the ladle has been poured the valve at 58 is turned to exhaust the compressed air whereupon the ladle'will return to its normal position; and the ladle and arm 45 are swung outwardly to the position in Fig. 3/ After a reasonable time for the molten cast iron to solidify, handle 24a is turned to the position shown in Fig.8 whereupon the drum and fixture are moved outwardly and as the outer sides of the segments of the fixture leave the contracting flange 7 around them they are automatically expanded through the force of the compressed spring 27, and the composite drum 41 lined with a cast metal lining 64 integrally fused thereto is removed from the fixture and the apparatus is in condition for a repeating of the process.

The construction described is one very practical and useful and has proved exceptionally practical in quantity production of composite drum structures of the character described. The range of the temperature for the molten iron should be between 2600 and 3000 F ahrI. In practice for the best results and to secure a complete fusing at the contacting surfaces of the molten cast iron and the outer pressed drum the temperature of the drum should not be much below 1350 Fahr, though satisfactory production in most cases can be obtained with the outside drum at 1200 of more Fahr. with the temperature of the molten cast iron higher than the minimum of 2600 F ahr. which has been stated. The invention is defined in the appended claims and is to be considered comprehensive of all forms of structure coming within their scope.

I claim:

1. In a machine of the class described, a rotatably mounted shaft, means for driving the same, a head open at one end and having tapered inner sides at one end of the shaft, a tubular shaft mounted lengthwise of the first shaft, a second head mounted at one end thereof and located within the first head, a rod located lengthwise of the tubular shaft, a'threaded head secured at one end of the rod ad acent the second head and within the first named head, a fixture adapted clamp against a substantially cylindrical drum of rolled or pressed metal comprising, a plurality of segments connected with the two last mentioned heads, means for selectively moving the tubular shaft longitudinally in either direction to draw said fixture into the first head and close the segments thereof against the drum, and yielding means for causing said segments to separate on longitudinalmovement of the tubular shaft outward to carry the fixture segments out of the first mentioned head.

A construction of the class described, comprising, a horizontal rotatably mounted shaft, an enlarged head having an open outer vertical side at one end of the able therewith, means for driving the shaft,

pushed partially out of said head, said segto receive and ments having inwardly extending wings at their inner ends, a rod located lengthwise of and within the tubular shaft, means for pivotally connecting the inner ends of said wings to an end of said rod, means for connecting each of said segments to an end of said tubular shaft, spring means housed within the tubular shaft acting on said rod tending to force-the same outwardly, and means-for selectively moving said tubular shaftlongitudinally .in either direction. A

3. In a construction of the class described, a rotatably mounted head havingan open side the inner sides ofi said head being tapered inwardly, a drum holding fixture comprised of a series of segments located around the axis of said head, means for rotating the head,

'means for simultaneouslydrawing all of the DONALD J. CAMPBELL.

' ioo

Images