US3445904A - Apparatus for making forgings - Google Patents

Description

G. HARRKSON ET AL. 3,445,904

APPARATUS FOR MAKING FORGINGS Filed Oct. 6, 1966 Sheet 3 of4 J m@ N i U V. NS T 50! T 59 R oR TRH N E K VE gm a, on E5 G W S 1 b N E y 1969 G. HARRISON ET AL. 3,445,904

APPARATUS FOR MAKING FORGINGS Sheet 3 of 4 Filed Oct. 6. 1966 INVENTORS mmm R y NM o m M w 5 m A A m H K m 3 N 3 $9 40 y 27, 1969 G. HARRISON ET AL 3,445,904

APPARATUS FOR MAKING FORGINGS Filed Oct. 6, 1966 Sheet 4 of4 NL F. M Ilrl .523 9 $5 $6 Can a E .Y mwt z G2 i mm: M JQW mEu N l ma m B2 mH w m m3} NW qow mwmou v/ II w 1 I NvE Av: Ii n mmSM ll f? m= J mmZ MEU 5% INVENTORS GEORGE HARRISON NELSON K. Hanmsmu b 5M 4 0021mm Arm s.

United States Patent v 3,445,904 APPARATUS FOR MAKING FORGINGS George Harrison, Berwyn, and Nelson K. Harrison,

Riverside, Ill., assi'gnors, by mesne assignments, to

North American Rockwell Corporation, Pittsburgh,

Pa., a corporation of Delaware Filed Oct. 6, 1966, Ser. No. 584,695 Int. Cl. B23p 23/04 US. C]. 29-33 13 Claims ABSTRACT OF THE DISCLOSURE A machine for casting and forging metal pieces in which the casting metal is caused to engage a support adjacent to the casting mold and, following casting,.the cast piece is separated from the mold and carried by the support to a forging station for the forging operation and is thereafter carried by the support to the trimming station where the forged part is separated from the trim part.

This invention relates generally to casting and forging,

and more particularly to a novel method and apparatus for making forgings.

It is an object of this invention to provide a method and apparatus for making metal forgings in which metal is cast into a main cavity portion of a mold member, and after the main cavity portion has filled, an overflow of metal is channelled onto an adjacent supporting surface to cast the metal thereon. After the casting has solidified, the mold parts are retracted from the casting. The engagement of the solidified overflow with the support acts to strip the casting from the mold parts and leave the casting firmly in place on the support. While the casting is still hot, the support is shifted to move the casting between forging dies to forge the metal that was cast in the main cavity portion of the mold. The solidified overflow metal remains attached to the support at the places where the metal was cast thereon. Thereafter, the support is moved to bring the forged piece and excess metal (constituting the overflow and flashing from the forging) to trimming dies which punch out the forged piece leaving the scrap or trim attached to the support. Thereafter, the support is again shifted to a position wherein the scrap metal may be ejected from the support.

It is a further object of this invention to provide a method and apparatus of the type stated in which the cast ing is carried out in an open top mold and in which there is a chilled core that penetrates partially into the main cavity portion of the mold and against which the liquid metal solidifies. There is a space around the core for the flow of metal into the mold after the level of metal in the mold has reached the level of the core so that the shrinkage of the solidified metal is in the region between the chilled core and the adjacent upper end portion of the mold cavity wall. Preferably, the core is located relative to the mold cavity wall such that the shrinkage takes place in a region of the casting into which the flow of metal during the forging is great. In the forging operation there is a flow of metal between the dies toward the shrinkage area which tends to fill the shrinkage void, resulting in a forging that is free from unwanted voids and cracks. The recess left by the core is also forged out during the forging operation. In general, the core should approximately be' centered with respect to the main cavity portion of the mold, so that the shrinkage is near the outer edge of the part of the blank that is forged.

When casting into an open top mold and using a permanent core to form a casting having a hole therein, the metal flows around the core to form a hole which is a counterpart of the shape of the core. As the hot metal feedsinto the mold cavity through a runner, the metal "ice that solidifies around the core tends to shrink as the metal from the runner is being fed into the cold cavity. When the mold has filled, the metal shrinkage occurs in the reg1on between the runner and the core and usually results in a crack extending from the hole generally toward the runner.

It is a further object of the present invention to provide a method and apparatus for making a casting, which may be a forging slug, in which a hole is formed partially or completely through the casting but which eliminates the formation of a crack or cracks adjacent to the hole. In accordance with this object of the invention, the metal is cast into the open top mold in which there is a thin tubular core that is heated to a high temperature, less than the solidification temperature of the metal but much greater than the temperature of the cavity Wall, which may be water-cooled. As a result, the metal that flows around the heated core is not permitted to chill rapidly. The heated core and mold are separated after the metal has solidified around the core an amount sufiicient to be form-sustaining but while the metal is still quite hot and still able to undergo a substantial amount of shrinkage. Because the overwhelming amount of shrinkage takes place with the core removed and the shrinkage is substantially uniform around the hole rather than localized, cracking adjacent to the hole is avoided.

It is a further object of the present invention to provide a press, such as a forging or a punching press, which has a short stroke but yet is capable of imposing high pressure upon a workpiece that requires a large clearance between the dies in order to get the workpiece between the dies. In accordance with this object of the invention, the press may be of the toggle link type with two dies on opposite sides of the workpiece that are both movable toward the workpiece. At least one of the dies may be retracted relative to the other die to provide clearance for the workpiece. When the workpiece is in position, the one die may again be shifted toward the workpiece to take up the clearance and position the die preparatory to working the piece. Since the aforesaid movement of the one die does not operate on the piece, the die may be moved by an auxiliary low power source. When the two dies are in position, the main power source may be actuated to operate on the piece.

The attainment of the above and further objects of the present invention will be apparent from the following detailed description, reference being made to the accompanying drawing forming a part thereof.

In the drawing:

FIG. 1 is a vertical sectional view of a machine con- 'structed in accordance with and adapted to carry out the method of the present invention;

FIG. 2 is a partial sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is a fragmentary sectional view and partially broken away taken approximately along line 3-3 of FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3;

FIGS. 5, 6, 7 and 8 are fragmentary sectional views taken along lines 5-5, 6-6, 7-7 and 8-8 of FIG. 3;

FIG. 9 is a fragmentary sectional view taken along line 9-9 of FIG. 2;

FIG. 10 is a fragmentary sectional view taken along line 10-10 of FIG. 1;

FIG. 11 is a fragmentary elevational view of the structure of FIG. 10;

FIG. 12 is a fragmentary sectional view similar to FIG. 5 and showing a heated core used to make a casting with a hole therethrough;

FIG. 13 is a diagram of a hydraulic circuit for the machine of the present invention; and

FIG. 14 is a schematic of the circuit for controlling the automatic operation of the machine.

Referring now in more detail to the drawing, 1 designates a machine comprising a base 2 having a bottom plate 3, upstanding side walls 5, 6, 7, 8 and a top plate 10. The foregoing parts of the base 2 are suitably joined together and reinforced by an appropriate number of angle members. The top plate 10 has a hole 11 for receiving a bearing cup 13 which is secured to the top plate 10 by circumferentially spaced screws 14. A turntable 15 projects into bearing cup 13 and is supported therein by a thrust bearing 17, the latter being held in place by bearing retainers 18, 19.

The turntable 15 has four radial turntable arms 20, 21, 22, 23 which are 90 degrees apart. Each of the turntable arms 20, 21, 22, 23 terminates in spaced parallel radial fingers 25, 26 with the fingers having radially outwardly and laterally inwardly opening slots 27 which, as best shown in FIGS. 5-7, are T-shaped in cross section for purposes presently more fully appearing.

Secured to the outside of the side wall 5 through a bracket plate 29 is a hydraulic cylinder 31 that has a vertically reciprocating piston rod 32, the upper end of which carries a mold-support plate 34. An open top copper mold member 35 is secured as by screws 37 to the upper surface of the mold support plate 34.

The mold member 35 has a width which is slightly less than the distance between the fingers 25, 26, there being a slight clearance to permit the mold 35 to be shifted to a raised or casting position between the fingers 25, 26 and to a retracted position below the fingers 25, 26, as controlled by the operation of the piston rod 32.

The mold member 35 has a mold cavity 38 that comprises generally a main cavity portion 39 in which a forging slug is cast, a mold entry way runner 41, and four runners 42, two on each side of the central portion 39. The runners 42 extend to the lateral margins of the mold member 35, namely those margins that are adjacent to the spaced fingers 25, 26 when the mold member 35 is in its raised position. The mold member 35 also has a passageway 43 by which Water may be circulated through the mold from a water inlet tube 45 to a Water outlet tube 46 to chill the mold continuously.

For reasons hereinafter more fully explained, the casting operation is preferably carried out with another mold member, namely a water-cooled copper core 47. The core 47 may have a lower generally spherical head 48 that projects a short distance into the upper end portion of the mold cavity 38, somewhat centrally of the main cavity portion 39. The core 47 may have a suitable passageway 49 therein so that it may be continuously water-cooled. For this purpose, there is provided a water inlet pipe 50 and a water outlet pipe 51. The core 47 has an upwardly extending stem 53 which is clamped to a horizontal bar 54, the latter, in turn, also being clamped to a piston rod 55. This piston rod 55 projects loosely through the turntable '15 and is driven by a hydraulic motor 57, comprising a piston and a cylinder, that is suitably mounted on the bottom plate 3. This hydraulic motor 57 may be operated to lower the core 47 into molding position or to raise the core from the completed casting by moving the core to the broken line position shown in FIG. 5. The piston rod 55 may be hollow so that the water supply tubes for the core 47 may, if desired, extend therethrough.

To form a casting, the mold member-actuating cylinder 31 and the core-actuating cylinder 57 are operated to bring the mold member 35 and core 47 from their broken-line positions, shown in FIG. 5, to the full-line positions shown in FIGS. 5 and l. The mold member 35 is thus placed between the fingers 25, 26, such that the bottoms of the runners 42 coincide substantially with the lower edges 59 (FIG. 5) of the slots 27, 27. Preferably, the depth of the runners 42 adjacent to the edges 59 is approximately the same as the height of the slot opening at 59. The core 47 is lowered so that the major part of its arcuate head suitable mold release lubricant may be applied to the core head 48 and to the mold cavity 38. Molten metal, such as brass, aluminum or steel, is poured into the mold gate 60, and the molten metal flows downwardly through the entry runner 41 to fill the mold cavity 38. As the mold cavity 38 fills, the molten metal will first fill the main cavity portion 39. The overflow from the main cavity portion 39 will flow into and fill the runners 42 and from there will flow into the slots 37 so that the casting C is not only cast in the mold but also onto the fingers 25, 26. As the metal cools, it will shrink placing the metal in the runners 42 in tension, thereby resulting in the metal in the slots 27 being drawn into tight frictional engagement with the fingers 25, 26. The T-shape or undercut of the slots 27 prevents withdrawal of the metal from the slots 27. Thus, the main or forging slug portion 39 of the casting C is rigidly joined to the supporting fingers 25, 26 by a web of metal formed by the solidified overflow.

As the molten metal reaches the level of the chilled core 47, the metal engaging the core 47 will promptly solidify with the result that in further feeding of the metal to take up shrinkage, the flow of metal is around the core 47. When the metal fully solidifies, shrinkage will be in a region 61 (FIGS. 1 and 5) around the core and near the periphery of the mold portion 39 of the casting C. This will avoid the formation of a deep shrinkage crack at the center of the forging. The core 47 will, of course, leave an arcuate but crack-free depression 62 in the casting C.

The cylinders 31, 57 may then be operated to raise the core 47 and lower the mold 35. When this is done, the grip of the solidified web of overflow metal with the fingers 25, 26 results in stripping the casting C from the mold, leaving the casting rigidly supported on the fingers 25, 26. After a suitable time interval to allow the casting to solidify fully but while it still retains its heat of casting and is at or near a suitable temperature for hot forging, the turntable may be rotated counter-clockwise (FIG. 3) 90 degrees in a horizontal plane to bring the casting C between the dies of a forging mechanism, designated generally at F, and hereinafter more fully described.

To rotate the turntable 15, the latter has a gear 63 rigidly secured to the lower side thereof and driven by a pinion 65. A conventional rotary hydraulic motor 66 that is capable of rotation in both directions supplies power to drive the pinion 65. This motor 66 is rigidly secured to a bracket 67 that is secured to and depends from the underside of the top plate 10. The motor shaft 69 projects upwardly and is journalled in the top plate 10. On the motor shaft 69 is a one-way clutch 70 of conventional construction. The driving portion of the clutch 70 rotates with the motor shaft 69 while the driven portion of the clutch is coupled to the pinion 65 so that the pinion 65 rotates only in one direction, namely clockwise as viewed from FIG. 3. Above the pinion 65 is a cam 73 that is secured by the set screws 74 to the driving portion of the clutch 70 to rotate the cam 73 jointly with the motor shaft 69. The cam 73 rotates 270 degrees between two adjustable screw stops 76, 77. The ratio between the pinion 65 and gear 63 is such that rotation of the cam 73 from abutment with the stop 76 to abutment with the stop 77 causes the turntable 15 to rotate 90 degrees. When the motor 69 reverses its direction of rotation, the cam 73 will rotate until it engages the stop 76, but the pinion 65 will not rotate.

A releasable locking mechanism 79 (FIGS. 3 and 4) is employed to hold the turntable 15 rigidly in position after it has been rotated 90 degrees, the mechanism 79 being releasable prior to rotating the turntable 15. This mechanism comprises a bell crank 80 that is pivotally secured to a block 81 below the top plate 10. One arm of the bell crank 80 has a depending indexing pin 83 that engages between two teeth on the gear 63. A hydraulic cylinder 84 has a piston rod 85 that is pivotally secured to the other arm of the bell crank 80 by a pin 86. The

cylinder 84 also is pivotally secured by a pin 88 to a bracket 89, the latter being in turn bolted to the underside of the top plate 10. When the piston rod 85 is moved to move the pin 86 toward the cylinder 84, the pin 83 will be retracted from between the teeth on the gear 63, thus permitting the turntable 15 to be indexed. When the piston rod 85 moves in the opposite direction, the pin 83 is urged tightly between two teeth on the gear 63 to lock the turntable in position.

Because the pinion 65 might continue to rotate even though the cam 73 has stopped and thus causes overindexing of the turntable, braking may be applied to the turntable. This may consist of a brake mounted on the top plate 10. This brake comprises a brake shoe 92 having a lining 93 that engages the upper face of the gear 63. A sleeve 95 is threaded into the top plate and receives an adjusting screw 96 and a coil-compression spring 97, by which the pressure of the lining 93 on the gear 63 may be adjusted. The drag of the brake thus causes the turntable to stop when torque is no longer applied to the pinion 65.

Turning now to the forging mechanism F, this mechanism comprises upright generally trapezoidal-shaped plates 99, 100 that project above and below the top plate 10. L-shaped brackets (FIG. 3) 102, 103 are bolted to the top plate and to the plates 99, 100 to secure them in place. Near those vertical edges of the plates 99, 100 that are adjacent to the turntable are sets of gibs 107, 108 for slidably receiving die holders 105, 106 that reciprocate equally vertically toward and away from each other. As best seen in FIGS. 2 and 6, the die holders 105, 106 carry forging dies 110, 111 that are suitably secured to the die holders as by screws 113.

The die holders 105, 106 form part of a hydraulically actuated toggle link arrangement by which equal and opposite forces may be applied to the forging dies 110, 111 and hence to the forging slug portion 39 of the casting to make the forging 1. Between the plates 99, 100 and bolted to each is ahydraulic cylinder 114 having a piston rod 115. At the end of the piston rod 115 is a clevis with a block 17 that slides in horizontal guide slots 118 in the plates 99, 100. Links 119, 119, 121, 121 are pivotally secured to the clevis pin 122, and the links 119, 119, 121, 121 are in turn pivotally secured to rocker arms 123, 125 by pins 126, 127. The ends of rocker arms 123, 125 are pivotally secured by pins 129, 130 to the ends of the die holders 105, 106. Between their opposite ends the rocker arms 123, 125 are pivotally secured by a pin 131 and an eccentric 133 to links 134, 134, 135, 135 which are in turn pivotally secured by pins 137, 138 to the plates 99, 100. The purpose of the eccentric 133 will be hereinafter described.

In FIG. 2 the forging mechanism F is shown in its forging position. When the piston rod 115 moves to the right (FIG. 2), the die holders 105, 106 and forging dies 110, 111 will separate and will assume the broken line positions shown in FIG. 6. During the forging operation the forging dies 110, 111 move toward each other and apply equal and opposite forces to the casting. The metal is not stripped from between the fingers 25, 26 but remains in the slots 27. When the forging dies are retracted in a manner hereinafter more fully described, they are out of the way of the workpiece allowing the turntable to be indexed 90 degrees to a punching mechanism P. The turntable thus carries with it the workpiece.

During the forging there is a large flow of metal in the peripheral region 142 of the forged piece 7. This was the region of shrinkage of the casting. However, the flow of metal during the forging tends to fill the forging dies at the peripheral region so that the forging is not left with a shrinkage or incompletely shaped section. Likewise, the depression 62 is forged out of the metal. The flashing 141 from the forging tends to push the metal that solidified in the mold runners 42, and to which the forging remains attached, toward the fingers 25, 26. The forces tend to 6 place this flashing 141 and the metal that was cast in the runners 42 in compression and thereby impost forces on the fingers 25, '26 tending to push them apart. However,

the reaction forces of the fingers 25, 26 maintain the lingers in tight frictional engagement with the metal in the slots 27 after the forging, Consequently, when the forging dies are separated, the web of metal that joins the forging to the fingers 25, 26 results in the forging being stripped from both forging dies.

The trimming or punching mechanism P is in many respects similar to the forging mechanism F in that the punching mechanism P is a hydraulically actuated toggle link arrangement for operation of punching dies 146, 147. Accordingly, the parts of the punching mechanism P that are the same as those of the forging mechanism F have corresponding numerals followed by the letter p.

The punching die holders 143, 145 respectively carry the male and female punching dies 146, 147. These die holders with their respective dies reciprocate vertically toward and away from each other. They and the toggle linkage are shown in their retracted positions in FIG. 1 and in full lines in FIG. 7. The broken line positions of FIG. 7 show the dies in their punching positions between and in closely spaced relationship to the indexing arm fingers 25, 26. Upon movement of the piston rod 115p to the left (FIG. 1) the dies 146, 147 move toward each other, entering between the fingers 25, 26. The dies 146, 147 are shaped such that upon contact with the metal held by the fingers 25, 26, the forging f is cut cleanly entirely around its periphery leaving the trim or scrap metal s secured in the slots 27. The scrap s thus extends continuously from one finger 25 to the other finger 26 and has a hole therein where the forging has been punched out.

The female die 147 and its die holder 143 are hollow to form a passage 149 of a size sufficient to enable the forging f to drop downwardly therein. At the lower end of the passage 149 is an inclined wall 150 which deflects the forging through a lateral opening 151 and onto an inclined chute 153 that is adjacent to the opening 151 when the trimming dies are retracted. The forging 1 may then slide down the chute 153 and into a suitable collecting bin.

Where the parting line of the forging is at or near the mid plane of the forging, or the depth of the forging below the parting line is small, the normal retraction of the forging dies 1 10, 111 and of the trimming dies 146, 147 will generally provide sufficient clearance to enable the workpiece to be inserted between and removed from the forging dies and to be inserted between the trimming dies. However, many forgings which may be made by the machine of the present invention, such as the herein shown forging 7, have the parting line very close to the top edge of the forging. Therefore, the present invention provides auxiliary mechanisms for retracting the lower forging die and the lower trimming die relative to the associated upper die to provide clearance between the dies for insertion and removal of the casting or forging, as the case may be. These mechanisms also move the lower trimming die and the lower forging die up to positions adjacent to the workpiece preparatory to the working operation. Such a mechanism is best shown in FIGS. 10 and 11 with respect to the lower trimming die 147, but it will be understood that a like mechanism is employed for actuating the lower forging die 111.

As seen in FIG. 10, the eccentric 133p is driven by a rotary hydraulic motor 192p that is rigidly secured to the link 135p through a space collar 194p. The motor shaft 195p fits into one end of the eccentric 133p and is keyed or otherwise rigidly secured thereto. At its opposite end the eccentric 133 2 has a cap 196p that is rigidly secured to the remainder of the eccentric by the screw and key connection shown. The cap 196p also has opposed shoulders 197p, 198p which are degrees apart and engage a stop pin 199p which is mounted on the link 135p that is adjacent to the cap 196p. The hydraulic motor 192p is reversible so that the eccentric and its cap will rotate 180 degrees in opposite directions.

When the pin 199p abuts the shoulder 198p, the lower trimming die 147 and its die holder 145 will be in the full line position shown in FIG. 1. In this position the lower die 147 is retracted sufliciently to provide clearance to enable the forging f to be placed between the trimming dies 146, 147. When the eccentric 133;) is rotated 180 degrees until the shoulder 197p and pin 199 engage, the throw of the eccentric will rock the rocker arm 125p clockwise (FIG. 1) to the broken line position shown in FIG. 1 and raise the die holder and die 147 up to the broken line position adjacent to the forging f. In this position the lower end of the forging is within the lower trimming die 147. During the aforesaid movement of the lower die 147, the upper die 146 and its die holder remain stationary. Thereafter, the cylinder 114p may be operated to move both dies 146, 147 to punch the forging from the scrap s. After the cylinder 114p has retracted the dies 146, 147, the hydraulic motor 192p is rotated to bring the shoulder 198p into engagement with the pin 199p to retract the lower die 147 and its die holder to the full line positions of FIG. 1 preparatory to receiving the next forging when the turntable is again indexed 90 degrees.

The corresponding arrangement on the forging mechanism F operates at the same time as does that on the punching mechanism P. Thus, when the lower forging die 111 is retracted, sufficient clearance will be provided between the dies 110, 111 for receiving the next casting and for allowing the completed forging to move from between the forging dies to the space between the trimming dies.

It is possible, of course, to increase the clearance between the respective pairs of dies by simply increasing the throw of dies of the forging and trimming presses. This can be done by using an ordinary pin in place of the eccentric 133p and increasing the distance between the element 133p and the pin 130. However, this would reduce the force-applying capability of the press, all other things being equal. Likewise, the throw of the dies can be increased and the forging or punching pressure kept constant by increasing the overall size of the press. By the present invention, however, adequate clearance for the workpiece is obtained while, at the same time, the press has a high force-applying capability and is kept to a relatively small size.

It will also be apparent that while the aforesaid dieretracting devices are shown with respect to the lower die of each of the forging and punching mechanisms F, P, similar devices may be employed to operate the upper dies simultaneously with the lower dies.

After the punching dies have been separated, the turntable 15 may then again be rotated 90 degrees to an ejector mechanism E by which the scrap s may be ejected or removed from the fingers 25, 26. As best seen in FIGS. 2 and 9, the ejector E comprises an arm 154, the lower end of which is pivotally secured by a pin 155 to a block 157. The block 157 is vertically movable in a slide 158 that is suitably secured to the lower end of a side wall 8. The lower end of the block 157 has lateral projections 159, 159 which abut the slide 158 to limit the upward movement of the block 157. At its upper end, the arm 154 is bolted to an ejector chute support block 161, the upper end of which has a downwardly inclined chute 162 thereon. The chute 162 has an upwardly extending flange 163.

A rotary hydraulic motor 165 is secured to the side wall 8 through a bracket 166. This motor 165, like the motor 66, may be capable of rotation in either direction through an angle of about 270 degrees. The shaft 167 of the motor 165 is rigidly secured to a rotor 169. Eccentric to the shaft 167, an actuator rod 170 is rotatably secured to the rotor 169 by pin 171. The rod 170 projects into a bore 17. in the ejector block 161, and surrounding the rod 170 is a coil compression spring 174. A cross pin 175 in the ejector block 161 may be used to retain the rod 170 in the bore 173 prior to pinning the rod 170 to the rotor 169 and also to keep the spring 174 preloaded.

When the turntable 15 is indexed to bring the scrap s to the ejector mechanism E, the latter is in a position shown in FIG. 2. The center of the pin 171 will be below the center of the shaft 167. The hydraulic motor 165 is then caused to rotate in the direction of the arrow 177 through an angle of 270 degrees. Upon an initial rotation of the rotor 169 the driving force of the rod 170 will be transmitted through the spring 174 to the block 161, the arm 154 and chute 162, thereby raising the flange 163 upwardly and arcuately between the indexing arm fingers 25, 26 and behind the scrap s. This movement of the flange 163 continues until the projections 159 abut the slide 158. Continued rotation of the rotor 169 then causes the flange 163 to swing to the left (FIG. 2) about the axis of the pin and thereby eject the scrap s from between the indexing arm fingers 25, 26, as shown in FIG. 8. During the movement of the flange 163 about the axis of pin 155 the rod 170 simply compresses the coil spring 174. The ejected scrap s may drop downwardly onto the chute 162 and from there into a suitable collecting bin. Thereafter, the motor is rotated in the reverse direction to its initial position.

While each operation of the machine has been described with respect to the metal held between the fingers 25, 26 on one of the arms, it will be apparent that similar operations will take place in connection with the metal between the fingers 25, 26 of the other arms. Thus, with reference to FIG. 3, the casting held by the arm 21 will be forged and the forging held by the arm 23 will be trimmed and the scrap in the arm 22 will be ejected. The mold and core may be brought into position between the fingers of the arm 20 preparatory to pouring a casting. Successive indexing of the turntable moves the arms 20, 21, 22, 23 into positions for the next operations so that for each indexing of 90 degrees there is a casting, a forging, a trimming and a scrap ejecting operation.

While the forging 1 herein shown in a single piece f, the machine may be used to make multiple forgings. For this purpose, the mold member 35 is designed with a main cavity portion having a multiplicity of sections so that each forging slug is joined to another by one or more webs of overflow metal that will ultimately become scrap. The core 47 will also be designed to project into each section of the main cavity. Of course, the forging and trimming dies are appropriately designed to forge and cut out the forgings so that all of the blanks are forged at one time, and during the trimming operation all of the forgings are trimmed from the metal and the group of forgings fall downwardly into the passage 149.

In some instances, it is desired to cast a forging slug portion 39 (or multiple forging slug portions) with a hole in each forging slug portion, as shown in FIG. 12. This will permit the fabrication of forgings, each having a hole therethrough. For this purpose, the chilled core 47 may be replaced by a tapered thin wall tube 176 having a bottom closure 178. The tube 176 is heated in a suitable manner as by a gas burner 179 that is suitably mounted for movement with the tube 176. The burner 179 heats the tube to a high temperature but below the meltting point of the metal. For instance, if brass is the metal being cast, the tube may be of stainless steel heated to about 1200 to 1300 F.

With the heated tube 176 in the mold and with the bottom 178 of the tube against the bottom of the mold cavity, the metal is poured into the mold cavity in the manner previously described. After the metal around the tube 176 has sufficiently solidified to be form-sustaining, the tube 176 is retracted leaving a counterpart-shaped hole in the casting. The metal around the hole is still quite hot and able to undergo a substantial amount of shrinkage, but because the overwhelming shrinkage takes place with the tube 176 removed, the shrinkage around the hole is substantially'uniform and does not tend to form a crack at the hole. The casting may then be forged, punched out, and the scrap ejected in the manner previously described. Of course, the foregoing method is applicable to produce a casting With a hole therein, even where there is no subsequent forging or punching operation.

The automatic operation of the machine will now be described and for this purpose reference should be had to FIGS. 13 and 14. As shown in FIG. 13, a source of hydraulic pressure HP (which may include a pump, ac cumulators, pressure boosters, etc.) supplies oil to a high pressure line h for delivery to the cylinders 31, 57, 114,

114p, 84 and to the hydraulic motors 66, 1-65, 192, 192p. Oil is returned to the hydraulic pressure source HP through a return or low pressure line 1. Oil to the moldactuating cylinder 31 and the core-actuating cylinder 57 is supplied through hydraulic lines 181, 182 under control of a valve V6. The valve Vc is selectively movable to either of two positions by solenoids S3, S4. When the solenoid S3 is energized and solenoid S4 is deenergized, oil flows to the cylinders 31, 57 through the line 182 and returns through the line 181 to raise the mold 35 and lower the core 47 each to their casting positions. Energizing the solenoid S4 and dcenergizing solenoid S3 reverses the flow of oil in the lines 181, 182 thereby to lower the mold and raise the core.

Oil to the forging cylinder 114 is supplied through lines 183, 185 and controlled by a valve Vf that is actuated by solenoids S1, S2. When solenoid S2 is energized and solenoid S1 is deenergized, oil flows through the line 183 and returns through the line 185 to retract the forging dies..When the solenoid S1 is energized and solenoid S2 is deenergized, the oil now in the lines 183, 185 is reversed to close the forging dies. Because the pressure for the forging cylinder 114 may be high compared to the pressure required for the other hydraulic components, a pressure booster piston and cylinder 215 may be interposed in the line 185.

Oil to the punching or trimming cylinder 114p is supplied through lines 186, 187 under control of valve Vp which is operated by solenoid S9 to move it to one position and by a return spring 188 that moves the valve Vp to its alternate position when the solenoid S9 is deenergized. With the solenoid S9 deenergized, oil flows through the line 186 and returns through the line 187 to retract the trimming dies. When the solenoid S9 is energized, the flow of oil in the lines 186, 187 is reversed to move the trimming dies toward one another and punch out the forging.

Oil to the ejectment hydraulic motor 165 is supplied through lines 189, 190 and through a valve Ve that is selectively movable to either of two positions by solenoids S7, S8. When the solenoid S8 is energized and solenoid S7 is deenergized, oil flows through the line 189 and returns through the line 190 to move the ejector flange 163 and chute 162 to their retracted or at-rest positions. When the solenoid S7 is energized and solenoid S8 is deenergized, the flow of oil in the lines 189, 190 is reversed to rotate the motor shaft 167 and eject the scrap from between the fingers25, 26 of that turntable arm that is at the ejectment position on the machine.

Oil to the lower die operating motors 1'92, 192p is supplied through lines 184, 188 and is controlled by a valve Vr that is actuated by solenoids S10, S11. When solenoid S11 is energized and solenoid S10 is deenergibed, oil flows through the line 184 and is returned through the line 188. This rotates the motors 192 192p to raise the lower dies 111, 147 preparatory to the forging and punching operations. When solenoid S10 is energized and solenoid S11 is deenergized, the motors 192, 192p, rotate to retract the lower dies to provide the added clearance space between each lower die and its associated upper die.

The indexing hydraulic motor 66 and the locking pin cylinder 84 are oil supplied through lines 191, 193 under control of a valve Vi. The valve Vi is selectively operable by solenoids S5, S6. When the solenoid S5 is energized and solenoid S6 is deenergized, oil flows through the line 193 and returns through the line 191 to urge the locking or index pin 83 into engagement between two teeth of the gear 63. The motor shaft 69 rotates to return the cam 73 to its initial position wherein it abuts the stop 76. Energizing the solenoid S6 and deenergizing solenoid S5 reverses the flow of oil in lines 191, 193 and releases the index pin 84 from between the teeth on the gear 63 and at the same time the oil pressure rotates the motor shaft 69 to drive the pinion 65 and thereby index the turntable degrees.

A circuit arrangement such as that shown in FIG. 12 may be used to control the sequence of operation of the various hydraulic cylinders and motors of the machine. A cam motor CM with a cam shaft CS drives a number of cams which are diagrammatically illustrated as CM1 through CM8. One revolution of the cam motor CM constitutes a cycle. These cams CM1 through CMS are shown in diagrammatic development, the distance from X to y representing 360 degrees of rotation of the cam shaft CS. The cams CM1 through CM8 respectively control the operation of cam switches 201 through 208, i.e. cam CM1 controls the operation of cam switch 201, cam CM2 controls the operation of cam switch 202, etc. The cams CM3 through 0M8 make and break the solenoid circiuts across the power lines L1, L2 to energize and deenrgize the solenoids S1 through S11 in proper sequence.

The circuit for starting and operating the cam motor CM comprises the cam switch 201, a pushbutton starter switch 200 and a relay coil RE. A first pair of normally open contacts RB1, operated by the relay coil RB, is shunted across the starter switch 200'. In series with the cam motor CM is a second pair of normally open contacts RB2, operated by the relay coil RB, and a pair of normally closed relay contacts RC2. An adjustable timer motor TM is provided to regulate the delay in indexing of the turntable after pouring the casting an amount of time sufficient ot allow the metal in the mold to solidify. The timer motor starting and operating circuit comprises the cam switch 202, a timer switch 209 that is operated by a cam 212 driven by the timer motor TM, a relay coil RC which operates normally open contacts RC1 and normally closed contacts RC2, and a timer motor cycle control switch 214 that is operated by a cam 213 driven by the timer motor TM.

At the commencement of a cycle, assume that there is no casting in the mold and that the cam section M31 engages the switch arm 203 to energize the solenoid S3 so that the mold is up in casting position and the core is lowered to casting position. The previously made casting is now on the turntable arm that is at the forging dies and that casting has been forged. The cam section M41 has caused the switch arm 204 to be in its full-line position to energize the solenoid so that the forging dies are separates. The casting on the arm at the trimming or punching dies has been trimmed from the scrap and the cam section M71 has opened the switch 207 so that no current is flowing through the solenoid S4, keeping the trimming dies in their open or retracted positions. The cam section M61 is holding the switch arm 206 so that the solenoid S8 is energized keeping the ejector mechanism in its retracted or at-rest position. The scrap s has been ejected in the previous cycle of operation. The cam section M51 maintainsthe switch arm 205 in position to energize the solenoid S5 so that the index or locking pin 83 holds the turntable in the locked position. The cam section M81 closes switch 208 so that solenoid S11 is energized whereby the lower forging and trimming dies are in their raised positions.

A proper amount of liquid metal is introduced into the mold and thereafter the pushbutton starter switch 200 1 1 is closed by the machine operator. Upon release of the switch 200 its return spring causes the switch to break contact. Since the cam switch 201 is closed by the cam section M11 at the time the starter switch 200 is depressed, the relay coil RB is energized. Energizing the relay coil RB closes the pair of contacts RBI and the pair of contacts RB2 so that upon release of the pushbutton switch 200 the relay coil RB remains energized, and in addition a circuit is established through the cam motor CM causing the same to begin rotation.

Almost immediately after the circuit has been established through the cam motor CM, the cam section M21 closes the switch 202 thereby energizing the relay coil RC through the closed timer switch 209. Energizing the relay coil RC opens the normally closed contacts RC2 to stop the cam motor CM. Energizing the coil RC will close contacts RC1 to start the timer motor TM.

After the timer motor TM has operated for the preset time to allow metal in the mold to solidify, the timer motor TM opens the timer switch 209 to deenergize the relay coil RC and reclose the contacts RC2, thereby causing the cam motor CM to resume its rotation. The time interval after which the timer switch 209 is opened after the timer motor TM begins rotation may be determined by the selected angular position of the cam 212 on the timer motor shaft.

When the timer motor TM commences operation upon closing of the contacts RC1, the timer motor TM causes the cam 213 to rotate causing the normally open switch contacts 214, which are shunted across the contacts RC1, to close. The timer motor TM continues its cycle of rotation after opening of the contacts RC1 until the action of the cam 213 opens the contacts 214. Rotation of the timer motor TM through its cycle results in reclosing or resetting the timer switch 209. However, before the timer switch 209 is reclosed, the cam motor CM has rotated sufficiently to cause the cam switch 202 to move onto the cam section M22, thereby opening the cam switch 202 and preventing relay coil RC from being energized When the switch 209 is reset.

After the cooling delay, the cam section M32 moves the switch arm 203 to the dotted line position to energize the solenoid S4 and thereby lower or retract the mold and at the same time elevate the core. Then the cam section M82 moves the switch arm 208 to energize the solenoid S10 and deenergize the solenoid S11. This retracts the lower dies 111, 147 to provide the clearance space for the workpieces. Thereafter, the cam section 52 moves the switch arm 205 to energize the solenoid S6 which releases the indexing pin 83 and operates the indexing motor 66 to index the turntable 90 degrees. Thereafter, the switch arm 205 engages the cam section M53, resulting in the solenoid S6 being deenergized and the solenoid S being energized. This locks the indexing pin 82 in position and returns the motor 66 to its initial position. With the workpieces now between the respective pairs of dies in the forging and punching mechanisms F, P, the cam section M83 then moves the switch arm 208 to energize the solenoid S11 and deenergize the solenoid S to raise the lower dies preparatory to the forging and trimming operations.

Next, the cam section M42 engages the switch arm 204 to energize the solenoid S1 to close the forging dies and forge the casting therebetween. In the meantime the switch arm 203 becomes engaged by the cam section M3 3 to energize the solenoid S3 to raise the mold and lower the core preparatory to the next cycle of operation. After the forging is completed, the cam section M43 moves the switch arm 204 to deenergize the solenoid S1 and energize the solenoid S2 to retract the forging dies.

Before the forging dies have been retracted, the cam section M72 engages the switch arm 207 to energize the solenoid S9 and close the punching dies. While the punching dies are still closed, the cam section M62 engages the switch arm 206 to energize the solenoid S7 to operate the ejector motor 165 and eject the scrap s. Thereafter,

the cam section M73 releases the switch arm 207, allowing the return spring 188 to move the valve Vp to the position shown in FIG. 11 and retract the punching dies. Thereafter, the cam section M63 engages the switch arm 206 to energize the solenoid S8 and deenergize the solenoid S7, which reverses the rotation of the ejector motor 165 and returns the ejector mechanism to its initial position.

At the end of the cycle a short cam section M12 engages the cam switch 201, momentarily opening the same. This breaks the circuit to the relay coil RB and opens the relay contacts RB2, RBI and stops the operation of the cam motor CM. The cam section M12 is quite short, with the result that the inertia of the cam motor causes the switch 201 to be reengaged by the cam section M11 to close the switch 201 preparatory to the initiation of the next cycle of operation of the machine.

In compliance with the requirements of the patent statutes we have herein shown and described a preferred embodiment of the invention. It is, however, to be understood that the invention is not limited to the precise construction herein shown, the same being merely illustrative of the principles of the invention.

What is considered new and sought to be secured by Letters Patent is:

1. Apparatus for making metal forgings comprising a mold for casting metal, a support adjacent to said mold and having means for receiving some of the metal that is cast and gripping said metal upon solidification of the casting, means for separating the mold from said casting to leave the casting held by said support means for forging the casting to a different shape after separation thereof from the mold and while the casting is held by said support, and means for providing relative movement between the support and the forging means to bring the casting and forging means into positions for forging the casting.

2. Apparatus according to claim 1 in which said means for separating said mold from said casting comprises means for moving said mold relatively to the support and in a direction to retract the mold from the casting, the

. grip of said support on said casting holding the casting to strip the casting from the mold as it is retracted from the casting.

3. Apparatus according to claim 1 in which the mold has a main cavity portion and means for channeling overflow metal from the main cavity portion to said support whereby the solidified overflow secures a slug of metal cast in said main cavity portion in spaced relation to said support.

4. Apparatus according to claim 1 in which the support comprises spaced fingers, the mold is positioned between the fingers during the casting operation and the forging means comprises opposed dies that enter between the fingers during the forging operation.

5. Apparatus according to claim 1 in which said forging means comprises forging dies on opposite sides of the casting, first means for moving one of the forging dies toward the casting to take up clearance between that die and the casting and place said one die in a position preparatory to forging, and second means for moving both forging dies toward the casting and into sufficient pressure engagement therewith to forge the same.

6. Apparatus according to claim 1 in which the forging means forges the casting to form at least one forged piece and trim means for severing said forged piece from said trim such that said trim remains on said support, said moving means being operable to move the support and severing meansrelative to one another to bring the severing means and forged casting into positions for operation of said severing means thereon, and means for removing said trim from the support.

7. Apparatus according to claim 1 in which said forging means comprises forging dies on opposite sides of the casting and means for causing relative movement of the dies and casting into and out of forging engagement of the dies with the casting, the metal after the forging operation remaining a unitary piece that remains gripped by said support to strip the forging from the forging dies as the forging and dies are separated.

8. Apparatus according to claim 1 in which said forging means includes opposed forging dies, indexing means for moving the support and casting to bring the casting between the forging dies; said forging means further comprising first means for moving one of the forging dies toward the casting to take up clearance between that die and the casting and place said one die in position preparatory to forging, and second means for moving both dies toward the casting and into sufficient pressure engagement to forge the same and form at least one forged piece from said slug and at the same time leave the forged casting attached to said support; means for severing the forged piece from the remainder of said forged casting while leaving the part of the forged casting attached to said support, said severing means including opposed dies on opposite side of the forged piece, said indexing means being operable to bring the forged piece between said severing dies when they are separated, and means for ejecting said attached part of the forged casting from said support.

9. Apparatus for making a casting having a hole therein comprising an open top mold member, a core, means for heating the core to a temperature below the solidification temperature of the metal being cast, means for inserting the heated core into the open top portion of the mold member, means by which the metal may be introduced into the open top portion of the mold to flow around the core to form the casting with a hole that is a counterpart of the core, and means for retracting the core from the mold member after the metal has solidified sufficiently to be form-sustaining but While the metal is still sufficiently hot to undergo substantial shrinkage, said apparatus further comprising means for forging the casting, and means for transferring the casting to the forging means.

10. A machine for making metal forgings comprising means including a mold for casting a workpiece, means for forging said workpiece, said forging means comprising opposed die members, at least die members on opposite sides of the workpiece, one of said die members having a first position in which the clearance between it and the second die member is sufficient to permit insertion of a workpiece therebetween, first means for moving said one die member from the first position toward the workpiece to a second position to take up th clearance between that die member and the workpiece and place said die member in a position preparatory to forging applying pressure to the workpiece, second means for moving both die members into pressure engagement with the workpiece and for retracting both of said die member from the workpiece to return said first die member to said second position, said first means being operable to return said one die member to said first position to permit insertion of a like workpiece between said die members, and means for positioning a cast workpiece in the space between the die members when said one die member is in said first position. I

11. Apparatus according to claim 10 in which said second means for moving both die members includes a toggle linkage and said first means includes only a part of the toggle linkage that is connected to said one die member for moving it independently of the other die member.

12. A machine for making metal forgings comprising a mold for casting metal, forging means for imposing pressure on a workpiece cast in the mold to deform the workpiece into a shape that is different from the shape of the originally cast workpiece, means for severing at least one portion of the forged workpiece from the remainder thereof, and means for providing relative movement between the workpiece and both the pressure imposing means and the severing means to position the cast workpiece for forging by said forging means and then to position the forged workpiece for severing by said severing means.

13. A machine for making metal forgings comprising a casting means including a mold for successively casting workpieces, forging means for deforming each cast Workpiece into a shape that is different from that of the original casting, means for removing the workpieces from the mold, means for supporting the removed workpieces, and means for providing relative movement between the workpiece supporting means, the casting means and the forging means to position a cast workpiece for forging by the forging means and at the same time place a Workpiece support in a position for receiving another cast workpiece.

References Cited RICHARD H. EANES, JR., Primary Examiner.

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