US3063108A

US3063108A - Automatic die casting machine

Info

Publication number: US3063108A
Application number: US800769A
Authority: US
Inventors: Frank P Gardner
Original assignee: Louis Marx and Co Inc
Current assignee: Louis Marx and Co Inc
Priority date: 1959-03-20
Filing date: 1959-03-20
Publication date: 1962-11-13
Anticipated expiration: 1979-11-13

Description

Nov. 13, 1962 F. P. GARDNER Y 3,

AUTOMATIC DIE CASTING MACHINE '7 Sheets-Sheet l INVENTOR. F24 /'\/K R GAEDNE/Z Nov. 13, 1962 F. P. GARDNER 3,063,103

AUTOMATIC DIE CASTING MACHINE Filed March 20, 1959 7 Sheets-Sheet 2 l 244 274 32 Ti :2. 4 A.

2%" Z54 INVENTOR. FRANK. R mA'BDNER ATTOE/VEYS Nov. 13, 1962 F. P. GARDNER 3,063,108

AUTOMATIC DIE CASTING MACHINE )INVENTOR. FQANK A QAkLW/Ee Nov. 13, 1962 F. P. GARDNER AUTOMATIC DIE CASTING MACHINE Filed March 20, 1959 v IZYVENTQRI WW J BY FRANK F 6,4 DA/ g A TTOE/VEXS Nov. 13, 1962 Filed March 20, 1959 F. P. GARDNER AUTOMATIC DIE CASTING MACHINE 7 Sheets-Sheet 5 I ll :1. 12.

INVENTOR.

FRANK F. (iAzoA/se True/vans Nov. 13, 1962 Filed March 20, 1959 F. P. GARDNER AUTOMATIC DIE CASTING MACHINE 7 Sheets-Sheet 6 n5 3 36 [E] 35 H 4 g q! 'LJ 0 f/f/ AT'EIID 95 l [02F 'i 14 i 62 l I q" 266 50 q l I /t I ii Cg Tic 1'7.

CLAMP FLU/V652 PLUNGER EETZ/RN CLAMP QELEASE TT 1a.

INVENTOR. FQ/I/VK R Qua/v52 BYf) M Nov. 13, 1962 F. P. GARD NER 3,063,108

AUTOMATIC DIE CASTING MACHINE Filed March 20, 1959 7 Sheets-Sheet '7 ,R. FRANK R-AZDNEZ Patented Nov. 13., 1962 3,063,108 AUTOMATKI DIE CASTING MACHINE Frank P. Gardner, Erie, Pa., assignor to Louis Marx & Company, Inc., New York, N.Y., a corporation of New York Filed Mar. 20, 1959, Ser. No. 800,769

' 9 Claims. (Cl. 22-68) This invention relates to molding, especially die casting, and more particularly to an automatic die casting machine. I

The primary object of the present invention is to generally improve die casting machines. A more particular object is to provide a die casting machine which is fully automatic and which operates cyclically without manual intervention.

Still another object is to obtain fast operation for high output, yet with adequate cooling time before actually ejecting the molded parts.

Still another object of the invention is to provide a machine which trims the parts and separates them from the gate in addition to ejecting the same from the die. In accordance with a further feature of the invention, the die itself is used as an important part of the trimming mechanism. It then'is convenient to eject the molded parts alone at the trimming station, and a further object of the invention is to provide a separate station for removing the remaining gate (the sprue and the runners) from the die.

Still another object of the invention is to combine the aforesaid mechanism with a standard die casting machine, preferably of the air operated type, in which case air is employed for some of the operations while electric motor driven mechanism is employed for other operations and also for timing, the different operations being favorably divided as between air and motor operation.

To accomplish the foregoing general objects, and other more specific objects which will hereinafter appear, my invention resides in the die casting machine elements and their relation one to' another as are hereinafter more particularly described in the following specification. The specification is accompanied by drawings in which:

' FIG. 1 is an elevation of a machine embodying features of my invention, with parts of the machine broken away at the top for lack of room;

FIG. 2 is a fragmentary transverse section taken approximately in the plane of the line 2-2 of FIG. 1;

" FIG. 3 is'a partially sectioned elevation similar to FIG. 1, but showing the upper left portion of the machine;

FIG. 4' is a view looking toward the stationary dies, that is, in the plane of the line 4-4 of FIG. 3;

FIG. 4Ashows the sprue vise in open position;

FIG. 5 is an end View of the machine looking toward the right end of FIG. 1;

FIGS. 6 and 7 show the gate here being cast, including the sprue and nine runners leading to eighteen pinions;

FIGS. 8 and 9 show one of the pinions, this being the cast product here being molded;

FIG. 10 is' a horizontal section through the dial shaft and carriage, and is taken approximately in the plane'of the line 10-10 of FIG. 1, without the cover die;

FIGS. 10A and 10B correspond to a part of FIG. 10, but show progressive relations of the parts;

FIG. 11 is a view looking toward the dial, with only two of the ejector dies mounted thereon;

FIG. 12 is a horizontal section taken approximately in the plane of the line 12-12 of FIG. 1;

FIG. 13 is a fragmentary section taken approximately in the plane of the line 13-13 of FIG. 12; FIG. 14 is a fragmentary section taken approximately in the plane of the line 14-14 of FIG. 12;

FIG. 15 is explanatory of a detail;

FIG. 16 is a view looking in the direction of the arrows 16-16 in FIG. 15;

FIG. 17 is a vertical transverse section through the machine taken approximately in the plane of the line 17-17 of FIG. 1;

FIG. 18 is a wiring diagram for the cam operated timing switches and solenoid valves;

FIG. 19 is explanatory of the timing;

FIG. 20 is a section drawn to enlarged scale and taken approximately in the plane of the line 20-20 of FIG. 10;

' FIG. 21 is a section through the ejector and cover dies when closed at the casting station;

FIG. 22 is a section somewhat like FIG. 21, but taken at the trimmer station;

FIG. 23 is a section through the timing shaft at one of the cam operated switches; and

FIG. 24 isan elevation of the cam operated switches.

Referring to the drawing, and more particularly to FIGS. 1- and 3, the automatic die casting machine comprises a stationary cover die 12 having an upright parting face, metal injecting means generally designated 14 (see also FIG. 10) for feeding molten metal to the cover die, and a dial 116 rotatable on a horizontal axis or shaft 18. The dial 16 carries a plurality of like ejector dies 20, and the radial relation of these on the dial 16 is shown in FIG. 11.

The machine further employs means to move the dial axially toward and away from the cover die 12, and in the present case this includes reduction gearing and cam mechanism driven by an electric motor 22 (FIG. 12), and also an air operated clamping means shown at 24 in FIG. 3 for increasing the die closing pressure during the injection of metal, that is, during the casting operation. The machine further includes indexing means which in the present case include a ratchet pinion 26 (FIG. 5) and a pawl 28 to cause the ejector dies 20 (FIG. 1) to register succesively with the cover die 12. The machine further comprises appropriate cam operated switches shown in FIGS. 18, 23 and 24 to operate the parts of the machine in properly timed relation.

Referring now to FIG. 4, the machine preferably includes not only the stationary cover die 12 at one dial station, but also a stationary trimmer die 30 at another dial station, and a sprue vise or gate pull means 32 at still another dial station. These are all located generally in the same plane, but are angularly displaced from one another, and in the particular case here shown they are located apart. However, as will be seen from inspection of FIG. 11, there are six ejector dies on the dial, located 60 apart, and the indexing means advances the dial 60 for each casting shot. Thus, much more cooling time is afforded before ejection and trimming, compared to opening of the die, and inasmuch as it is found that the die may be opened before the metal has set hard enough for trimming, the overall speed of operation and consequently the output of the machine are substantially increased. Forexample, with fifteen cycles or shots per minute, the die is opened after one or two seconds, butthe molded parts are not subjected to ejection and trimming until another four or more seconds after opening of the die.

Carriage Reciprocation zontal reciprocation for closing and opening the dies.

Referring now to FIG. 12 of the drawing, electric motor 22 is a gear-reduction motor with reducing gearing housed at 54. This turns a pulley 56 connected by a belt 58 (omitted for clarity) to a pulley 60, which may be formed integrally with a flywheel 62. The

parts

68, 62 are also shown in FIGS. and 14, which additionally show how they are rotatably carried by a pedestal 63 on base 42. They are keyed (key 61 in FIG. 14) on the hub of a pinion 64, the latter being freely rotatable on shaft 65, and meshing with a gear 66 (FIGS. 5 and 12) secured to the driving portion 68 of a clutch. The driven part 70 of the clutch is connected to a bevel gear 72. These parts are also shown in FIG. 13 in which shaft 74 is carried in bearing

pedestals

76, 78 secured to the base 42. The generally upright clutch operating lever 80 (FIGS. 5 and 13) is pivoted on the base at 82 and may be swung to one side or the other to engage or disengage the clutch, thereby starting or stopping the machine.

Referring to FIGS. 1, 5 and 12, bevel pinion 72 meshes with a bevel gear 86 on a horizontal shaft 88 carried in bearing 89 and two bearings 90 which latter form a part of the frame 40. Shaft 88 carries a miter gear 92 meshing with a miter gear 94 on the upright shaft 48.

Referring now to FIGS. 1, and 17, cam 50 is secured to upright shaft 48 by means of a hub 96. The upper face of the cam has a cam track 98 in which the cam roller 52 is received. The latter is rotatable on a pin 180 which is rigidly secured in the carriage 34. The latter is preferably thickened by means of a boss 102 to help strengthen the mounting of cam roller 52. From inspection of the shape of cam track 98 in FIG. 10, it will be seen that rotation of the cam will cause reciprocation of the carriage 34, and that it will remain in forward position for a large part of the revolution of the cam. It is during this forward dwell period that the die is clamped and molten metal is injected in and initially sets in the die.

Indexing Mechanism Referring now to FIGS. 1, 5 and 12 of the drawing, the horizontal shaft 88 carries a cam 104, one face of which has a cam groove or track 106. This receives a cam roller 108 (FIGS. 5 and 12) carried on an arm 110 pivoted at 112 on a bearing 114 secured to the base 42. A generally upright connecting rod 116 (FIGS. 1 and 5) is connected at its lower end 118 to the free end of arm 110, and is connected at its upper end 120 to a pawl plate 122. The latter is also shown in FIG. 10, and it will be seen that the hub 124 of pawl plate 122 is rotatable in the stationary frame plate 40.

In FIG. 5 the pawl plate 122 carries pawl 28 which engages ratchet pinion 26. FIGS. 1 and 10 show the unusual axial length of ratchet pinion 26, which keeps the pawl 28 in engagement with the pinion 26 during reciprocation of the carriage 34.

Inasmuch as the dial, weighted as it is with its ejector dies, may tend to over-travel, it is preferably provided with means to positively stop the dial at substantially correct index point. However, this stop action is preferably cushioned.

Referring to FIG. 20, the dial shaft 18 carries a ratchet wheel 130 with reversely directed teeth 132. There are six teeth corresponding to the six dial positions. When the dial is indexed, a tooth 132 bears against an overhung stop 134 and moves it from the initial or broken line position 134' to the solid line position 134. The base end of stop 134 is welded or otherwise secured to a slide 136 which meets a stationary stop screw 138. The position of the latter is adjustable in a block 140, and the adjustment may be locked by means of a lock nut 142.

The slide 136 is normally held in its retracted position by means of a compression spring 144 bearing against a collar 146 on a threaded rod 148. The other end of rod 148 is connected at 150 to the slide 136. The tension of spring 144 may be adjusted by means of lock nuts 152.

With this arrangement the indexing of the dial is positively stopped, and the stop action is cushioned. The indexing is performed while the dial is in and near its retracted position, and when the dial later is advanced axially the tooth 132 slides along and free of the stop 134, whereupon the latter with slide 136 is returned to the initial position 134. When the dial is again moved axially back, the tooth 132 is disposed ahead of the stop 134' and it is the next tooth 132' which will be stopped for proper indexing.

The carriage preferably is additionally provided with a friction brake to maintain the dial position as it is reciprocated axially, but the brake action is preferably relieved when the dies are nearly closed, in order to permit them to register in accordance with their own pilots.

Referring to FIGS. 1, 2, and 10, the dial shaft 18 is fitted with a brake drum 154 cooperating with an arcuate brake shoe 156. The latter is pivoted at 158, and its opposite end is urged downward by means of a compression spring adjustable at 161. The brake drum 154 is immediately adjacent the cushion stop ratchet wheel 130 (FIGS. 1 and 10) and the latter may be secured by screws (see 131 in FIG. 20) against the brake drum, with the latter being fixed to the dial shaft. In FIG. 2 it will be seen that the entire brake mechanism is mounted on the slidable carriage 34, and the brake shoe moves along with the drum so that the braking effort is applied continuously. When the dial has moved nearly all the way forward it is of some advantage, though not essential, to relieve the brake action so that the die will more readily close in accordance with its own piloting action. For this purpose the brake shoe may be provided with a cam roller 162 (FIG. 2), and the stationary rail 38 with a Wedge-shaped cam surface 164 (FIG. 1). The cam 164 is adjusted, either by shims or by sliding action, to relieve the brake pressure when the carriage has moved to its forward position.

Casting Mechanism Referring to FIG. 3, the casting mechanism here is intended for use with zinc, and it is of the submerged plunger type. More specifically, there is a pot of molten metal at 170, with heating means therebeneath at 172, and surmounted by an air cylinder 174. The latter drives a plunger 176 in a submerged cylinder 178 and forces metal upward through a gooseneck 180 to a nozzle 182. This entire mechanism generally designated 14 is mounted on the stationary head 184 by means of spaced trunnions 186. The angular position is determined by an adjustable screw threaded connection 188. It will be evident that adjustment at 188 may be used to adjust the position of and to tighten the fit at the nozzle 182.

Referring now to FIG. 21, the nozzle bears against a mating seat 190 in the cover die 12. As usual the metal flows through a main sprue passage 192, and the latter is preferably water cooled, as indicated by the cylindrical jacket 194. The entire cover die 12 preferably is water cooled, and cooling passages for that purpose are indicated at 196 and 198. Pipe connections are made at the top of the die (238 in FIG. 4) for the jacket 194 and the

passages

196, 198.

The ejector dies are not Water cooled. Water cooling is unnecessary because of the long interval between shots in any one die. The cover die 12 is being used continuously, whereas each ejector die is used only one-sixth als1 much, and has ample time for air cooling between s ots.

Referring now to FIGS. 8 and 9, the particular product here being made is a pinion 200 with a shaft hole 202, and having a flange 284 at one face. Such pinions are commonly employed in mechanism for toys and for other purposes, and are made in huge quantities.

The die may be laid out in various ways, and With different numbers of cavities. In the present case eighteen pinions are cast in onesh t, and these are disposed in a circle around the sprue, there being nine radial runners leading outward to pairs of pinions. The resulting gate iis shown in FIGS. 6 and 7, referring to which sprue 206 feeds metal through radial runners 208 leading outward to pairs of pinions 200. The individual pinions are edge gated atthe flange 204 of each pinion.

Reverting now to FIG. 21 of the drawing, the radial passages for the runners are formed in the ejector die onesuch passage being shown at .210. A mold cavity for forming a pinion is shown at 212, and as here designed ,the toothed portion of the pinion is formed in a die insert 214 forming a part of the cover die 12, while the flange ,is formed in an insert 216 in the ejector die. The hole through the pinion is formed by a core 218, the other end of which is secured at 220 in a laminated core plate 222.

The pinion may be ejected by means of a tubular ejector 224, the outer or rear end of which is secured in a laminated ejector plate 226. The latter is moved back to proper position when the die is closed by means of restoring pins 228. .Itmay be moved to the left for ejection by means of a stud 230 which is secured to the ejector plate at 232, and which passes through a clearance ,hole in the core plate 222. It also passes through the dial whichhas large triangular openings 223 (FIG. 11). The core plate 222 (FIG. 21) is not movable in the present case, itbeing fixed by bolts 234 with tubular spacers surrounding the same. Registration of the

die portions

12 and 20 as the die closes is assured by the usual pilots 236.

Referring now to FIG. 4 of the drawing, the cover die 12 may be rectangular, and the die cavities 212 are disposed in a circle about the sprue passage 192. Water cooling connections are shown at 238, andthere maybe separate connections for the sprue and the die, or the connections may be combined.

Land core pins. The plates are smallenough to fit in the jopenings 223.

Before'injecting metal into the die, it is imperative that W the diebetightly closed so as to withstand the parting pressure .at the parting face, and to minimize the formation of fin. The mechanical cam and sliding carriage arrangement so f ar described serves to provide the necessary die travel and indexing movements,but it would not be adequate to clamp the die tightly closed. For this purpose I provide an additional clamping mechanism which is air operated, and referring to FIG. '3 of'the drawing, the stationaryhead 184 carries an overhanging bracket 244) with an upright frame 242 for an air cylinder 24. The piston rod 244 is connected t'o thefree end of a cam 246 pivoted at 248. The cam surface bears on the sloping rear edge 250 of the dial as shown at 246, when the dial is in its forward orbrolrn line position.

5 When the cam 24i6is in its raised or retracted" position, it clears the dial 16 for its rearward oropening movement. I ,Because no appreciable movement or travel of dial 1 6 is required jto be produced by cam 248, the cam may be given a cam shapewhich develops a large closing pressure by reason of its sliding wedge 'action, and therefore the air cylinder24need not be large indiameter'.

It will be. understood that a separate and larger melting pot m'ay'be' associated with the pot I4 and arranged for automatic ladling ofaddit onal molten rnetal from the larger potin'to the pot 14, this being in accordance with "already known practice in the die castingart. "With a I supply ofjmolten metal assured, the machine becomes 6 fully automatic and requires little or no supervision by an operator. Trimming Mechanism The ejector die has bene designed to act also as one part of a trimmer die. The stationary trimmer'die is shown at 30 in FIG. 4, and it maybe quie simple, it comprising merely a plate with a ring of holes 252 proper dimension for the diameter of the pinion flange 204 (FIGS. 8 and 9). The pinions are pushed through the holes 252, and may then fall downthrough an appropriate chute 254 leading to a tote boxi Referring to FIG. 10, the trimmer die 30, when viewed in plan, comprises merely a front plate mounted on spaced supports 256. The individual holes may be provided with hardened tool steel bushings (see FIG. 22),' and the holes may diverge somewhat from front to rear, thus providing the desired trimmer cutting edge.

The manner in which the ejector die 2t) cooper-ates with the trimmer die 36 is shown in FIG. 22. The ejector die 20 corresponds to that shown in FIG. 21. "In FIG. 22 the ejector plate 226 has been forced to the left by its stud 230, and is therefore separated from the core plate 222. In consequence, the tubular ejector 224 has been advanced into the trimmer die 30 and has severed pinion 230 from the gate. The gate and fin are left behind in the ejector die 20. The ejector plate 226 may be restored to initial position by the restoring pins 228, which go into holes in trimmer die 36, but there are no corresponding holes in the cover die (12 in FIGS. 1, 4and21).

The mechanism for moving the ejector plate 226 to the left in order to trim the pinions from the gate may be described with reference to FIGS. 10, 10A and 10B. Referring to FIG. 10, the stud 230 of the ejector plate passes thru dial 16 and is aligned with a projecting screw 260 which is secured to a slidable bar 262' The projection may be adjusted by means of the thread, and the adjustment maybe locked by means of a lock nut 264. The bar 262 is carried by the slidable carriage 34-, and thus moves back and forth with the dial 16 and the stud 236. It is operated at appropriate timing by means of a cam follower lever 266 which is pivoted at 268. Lever 266 carries two different successively operated

cam rollers

272, 276 which are shown in FIG. 10, but more clearly in FIGS. 10A and 10B.

Referring to FIG. 10A, the main cam 50 has a cam projection27t) on its outer periphery. This approaches a cam roller 272 at a time when the bar 262'has moved leftward (with the carriage) to a point adjacent the roller 272. It will be seen that cam 270- bearing against roller 272 will move the latter against the sloping cam surface 274 of bar 262, thus moving it toward stud 230.

Referring now to FIG. 10B, as cam'270 leaves roller 272 it reaches a second cam roller 276 and moves the latter outward. This causes a further outward movement of roller arm 266 so that the first roller 272 travels further along the cam surface 27 4 and moves the stud 230 further to the left.

The first roller 272 may provide a limited travel with suitable force. This is desirable for the first part or the cutting action of the ejector sleeves, when there is greatest resistance to movement. Cam roller 276 is much nearer the pivot 268, and thus when cam 270 reaches roller 272 the motion of roller 272 is multiplied, so that at this time there is greater travel with less force, which is as it should be because after severance the ejection requires less force but more movement.

Reverting to FIG. 10, when the carriage 34 is in its righthand position, the sloping end 274 ofthe bar 262 is far to the right of roller 272, and at this time the peripheral cam projection 27% is far from the

rollers

272 and 276. However, as the main cam 50 rotates, and brings projection 2'70 around to the roller 27 2, the entire carriage 34 with the bar 262 moves 'to the left, and the parts are brought into proper working relation to etfect the desired ejection movement. This occurs during the dwell of the trimmer die in its closed position, and corresponds to the closed interval at the cover die for the casting operation.

The lever 266 is preferably forked or double, as is best shown in FIG. 17. It is pivoted at 268, and is channeled to straddle a part of the periphery of cam 50. The pins which carry the cam rollers extend between the top and bottom walls of the channel, with the rollers therebetween, as indicated at 272 and 276 for their corresponding rollers.

The bar 262 may be restored to initial position by resilient means, but here is positively restored by a mechanism which is illustrated in FIGS. 15 and 16 of the drawing. Referring to these, it will be seen that the bar 262 has a vertical pin 280 received in the bifurcated end 282 of a lever 284 pivoted at 286. A stationary adjustable stop bolt 288 on the fixed frame 40 bears against the end of lever 284 when the carriage is moved to the right. This causes a clockwise turning of the lever about pivot 286, which causes restoration of pin 280 and bar 262 to the right. Pin 286 is carried by a bracket 287 which is secured to the end of the horizontally slidable carriage. This is shown in FIG. 10.

Gate Pull r Ejection As so far described the remainder of the gate, that is the sprue and runners, remain in the ejector die, and referring to FIGS. 4 and 10, these are removed with the aid of a sprue vise shown at 32. The sprue vise comprises a stationary jaw 290 and a movable jaw 292. The latter is carried on slide rods 294 which are resiliently urged to the left by means of a compression spring 296. The jaws are opened momentarily by means of an air actuator 298, the plunger of which moves to the right in FIG. 4 in opposition to the compression spring, as shown in FIG. 4A, in which movable jaw 292 has been moved away from stationary jaw 290 by the plunger of actuator 298.

During advance of the dial the sprue is forced axially between the jaws, which then grip the sprue. As the dial is pulled back the sprue and gate are held by the vise, thus pulling the gate out of the die. When the dial has been retracted the vise is opened by the air cylinder and the sprue drops gravitationally into an appropriate tote box.

The timing of the air actuator 298 may be controlled directly by the reutrn movement of the dial, and this is shown in FIG. in which the operating arm 302 of an air valve 304 moves to the left or dotted line position 302 when the dial moves to the left, but is forced back to the solid line position 302 when the dial 16 has moved to the right as shown. This opens the air valve 304, and air is led through a flexible hose connection 306 to the actuator 298, which is single acting. Thus, the sprue vise is opened when the dial is in retracted position, but is closed most of the time. Indexing takes place while the dial is retracted, and when the dial again moves forward, the next sprue is pushed between the jaws and is there held.

Timing Mechanism The timing of many operations is determined by the mechanical relation of the parts and cams. It yvill be recalled that cam 104 (FIG. 1) times the indexing of the dial; cam 50 times the reciprocating travel of the dial; and cam 270 times the trimming. The timing of the clamp cylinder 24 (FIG. 3) and of the metal injection cylinder 174 is determined electrically, and may be accurately adjusted by means shown, FIGS. 23 and 24 of the drawing. The vertical shaft 48 carries a split sleeve 310, which in turn carries a series of cams 312. These are rotatably displaced, although the displacement is not shown in the drawing, and the exact location of each cam projection is adjustable by reason of slots 314. In FIG. 24 there five cams cooperating with five precision switches or micro switches marked 1, 2, 3, 4 and 5.

The manner in which each cam cooperates with the roller 316 of a micro switch will be clear from FIG. 23 of the drawing.

Referring now to FIG. 18, the clamp cylinder is controlled by a solenoid air valve 320, and the metal injecting air cylinder is controlled by a solenoid air valve 322. These are each four-way valves, and the air cylinders (24 and 174 in FIG. 3) are double acting. Switch 1 operates through conductor 324 to energize the solenoid which forces the clamp cylinder down in order to hold the die tightly closed. Switch 2 through conductor 326 energize the solenoid which sends the plunger cylinder down for the casting shot. Switch 3 through conductor 328 energizes the solenoid which restores the plunger to its return or up position. Switch 4 through conductor 330 energizes the solenoid of valve 320 which releases the clamp. All of these circuits have a common return conductor 332, with power being supplied at 334.

Switch 5 is optional, and in the present case through conductor 336 operates either a solenoid or a solenoid air valve which causes a spray of cleaning air with some lubrication mist against the ejector die in a selected station, most simply one of the idle stations between the three main working stations for casting, trimming and gate pull. This is shown at 342 in FIG. 4. Inasmuch as it is not necessary to clean and lubricate after each shot, a stepping relay or counter 340 (FIG. 18) may be interposed between switch 5 and the solenoid air valve 338. If this is done, the counter is preferably set to an odd number, say 5 or 7, so that the lubrication will be distributed over the six different ejector dies, instead of repeating on a favored ejector die.

The first four switches all operate within one-quarter revolution of the shaft, and this is indicated in FIG. 19, which shows how the positions for clamping the die; operating the plunger; returning the plunger; and releasing the die, are within Lubrication may take place elsewhere and at random, but it is mechanically convenient to locate it too within the 90.

Summary It is believed that the construction and method of operation of my improved automatic die casting machine, as well as the advantages thereof, will be apparent from the foregoing detailed description. With molten metal in the pot and with air supply available, the operator starts the motor and engages the clutch, whereupon the machine goes into operation. The dial moves forward to close the casting die, whereupon the clamp cylinder operates, and metal is injected into the die. It solidifies almost instantly because the die is cool. The injector plunger rises, the clamp is released, and the dial moves back with the ejector die. It is indexed ahead to the next position and again moved forward for another shot. On the next retraction, the dial is again indexed, which brings the first ejector die to the trimming station. At the trimming station the stud of the ejector plate is nudged forward by the

successive cam rollers

272 and 276, thereby trimming the pinions from the gate, and they descend gravitationally.

The dial again retracts and is indexed, thus bringing additional ejector dies to the cover die and trimer die, and moving the initial ejector die toward alinement with the sprue vise. On reaching that station, the sprue is forced into the sprue vise and there is gripped, so that during the next retraction of the dial, the gate is pulled out of the ejector die. On retraction of the dial, the sprue vise is openedand drops the gate. The operation continues uninterruptedly at a high rate of speed and with consequent high output.

It will be understood that while I have shown and described my automatic die casting machine in a preferred form, changes may be made in the structure shown without departing from the scope of the invention, as sought to be defined in the following claims.

I claim:

1. An automatic die casing machine comprising a single cover die having a parting face and having a sprue passage therethrough, means to eject molten metal under pressure through said sprue passage, a rotatable dial, a plurality of like ejector dies carried on said dial, said .dies having ejector pins for ejection in the direction of ranged for reciprocation, a ratchet pinion on said shaft,

a pawl operating on said ratchet pinion for indexing the dial, a cam for reciprocating the carriage, and a motor to drive both the indexing pawl and the cam, said ratchet pinion being sufliciently long in axial direction to remain in engagement with the pawl during reciprocation of the carriage.

2. An automatic die casting machine comprising a stationary cover die, a stationary trimmer die located in generally the same plane but displaced from said cover die, a rotatable dial a plurality of like ejector dies carried on said dial, said dies ejecting in the direction of the axis of the dial, means to move said dial axailly toward and away from said cover and trimmer dies in order to close and open the same, means to cause ejection after closing of the dies, means to index the dial to cause said ejector diesto mate successively with said cover die and trimmer die, whereby the castings are trimmed as they are ejected, and means toicause operation of the aforesaid means in properly timed relation, the aforesaid means including a dial shaft carrying said dial and rotatable in a carriage arranged .for reciprocation, a ratchet pinion on said shaft,..a.pawl operating on said ratchet pinion for indexing, the dial, a cam for reciprocating the carriage, and a m.otor.to driveboth the indexing pawl and the cam, saidiratchet pinion being sufficiently long in axiad direction toremain in engagement with the pawl during reciprocation of the carriage.

3. An automatic die casting machine comprising a single cover die having a parting face and having a sprue passage therethrough, means to eject molten metal under pressure through said sprue passage, a rotatable dial, a plurality of like ejector dies carried on said dial, said dies having die pilots, said dies having ejector pins for ejection in the direction of the axis of the dial, means to move said dial and all of said ejector dies bodily axially toward and away from said cover die for a substantial distance in order to close and open one of said ejector dies relative to the cover die, means to index the dial to cause said ejector dies to mate successively with said single cover die, and means to cause operation of the aforesaid means in properly timed relation, the aforesaid means including a dial shaft carrying said dial, a ratchet pinion on said shaft, a pawl operating on said ratchet pinion for indexing the dial, a motor to drive the indexing pawl, a ratchet wheel with reversely faced teeth on said shaft, and a resilient stop means engaged by one of said teeth to arrest the indexing motion, said stop means being disengaged when the dial is advanced to close the dies in order not to interfere with the normal action of the die pilots.

4. An automatic die casting machine comprising a stationary cover die, a stationary trimmer die located in generally the same plane but displaced from said cover die, a rotatable dial, a plurality of like ejector dies carried on said dial, said dies having die pilots, said dies ejecting in the direction of the axis of the dial, means to move said dial axially toward and away from said cover and trimmer dies in order to close and open the same,

1% means topauseejection after closingtof the dies, means .to index the dial to cause said ejector dies to mate successively with said cover die and trimmer die, whereby the castings are trimmed as they are ejected, and means to cause operation of the aforesaid means in properly timed relation, the aforesaid means including a dial shaft carrying said dial, a ratchet pinion on said shaft, a pawl operating on said ratchet pinion for indexing the dial, a motor to drive the indexing pawl, a ratchet wheel with reversely faced teeth on said shaft, and a resilient stop means engaged by one of said teeth to arrest the indexing motion, said stop means being disengaged when the dial is advanced to close the dies in order not to interfere with the normal action of the die pilots.

5. An automatic die casting machine comprising a single cover die having a parting face and having a sprue passage therethrough, means to eject molten metal under pressure through said sprue passage, arotatable dial, a

plurality of like ejector dies carried on said dial, said dies having die pilots, saiddies having ejector pins for ejection in the direction of the axis of the dial, means to move said dial and all of said ejector dies bodily axially toward and away from said cover die for a substantial distance in order to close and open one of said ejector dies relative to the cover die, means to index the dial to cause said ejector dies to mate successively with said single cover die, and means to cause operation of the aforesaid means in properly timed relation, the aforesaid means including a dial shaft carrying said dial, said shaft being rotatable in a carriage arranged for reciprocation, a ratchet pinion on said shaft, a pawl operating said ratchet pinion for indexing the dial, a cam for reciprocating the carriage, and a motor to drive both the indexingpawl and-the cam, said ratchet pinion being sufficiently long in axial direction to remain in engagement with the pawl during reciprocation of the carriage, a ratchet wheel with reversely faced teeth on said shaft, and a resilient or cushion stop means engaged by one of said teeth to arrest the indexing motion, said stop means being disengaged when the carriage is advanced to close the dies in order not to interfere with the normal action of the die pilots.

6. An automatic die casting machine comprising a stationary cover die, a stationarytrimmer die located in generally the same plane but displaced from said cover die, a rotatable dial, a plurality of like ejector dies carried on said dial, said dies having die pilots, said dies ejecting in the direction of the axis of the dial, means to move said dial axially toward and away from said cover and trimmer dies in order to close and open the same, means to cause ejection after closing of the dies, means to index the dial to cause said ejector dies to mate successively with said cover die and trimmer die, whereby the castings are trimmed as they are ejected, and means to cause operation of the aforesaid means in properly timed relation, the aforesaid means including a dial shaft carrying said dial and rotatable in a carriage arranged for reciprocation, a ratchet pinion on said shaft, a pawl operating said ratchet pinion for indexing the dial, a cam for reciprocating the carriage, and a motor to drive both the indexing pawl and the cam, said ratchet pinion being sufiiciently long in axial direction to remain in engagement with the pawl during reciprocation of the carriage, a ratchet wheel with reversely faced teeth on said shaft, and a resilient or cushion stop means engaged by one of said teeth to arrest the indexing motion, said stop means being disengaged when the carriage is advanced to close the dies in order not to interfere with the normal action of the die pilots.

7. An automatic die casting machine comprising a stationary cover die, a stationary trimmer die located generally in the same plane but displaced from said cover die, a sprue vise also located generally in the same plane but displaced from said cover and trimmer dies, a rotatable dial, a plurality of like ejector dies carried on said dial, said dies having die pilots, said dies ejecting in the direction of the axis of the dial, means to move said dial axially toward and away from said cover and trimmer dies in order to close and open the same, means to cause ejection after closing of the dies, means to index the dial to cause said ejector dies to mate successively with said cover die and trimmer die and sprue vise, whereby the castings are trimmed as they are ejected, and the residual sprue and runners are removed from the ejector die by the sprue vise, and means to cause operation of the aforesaid means in properly timed relation, the aforesaid means including a dial shaft carrying said dial and rotatable in a carriage arranged for reciprocation, a ratchet pinion on said shaft, a pawl operating said ratchet pinion for indexing the dial, a cam for reciprocating the carriage, and a motor to drive both the indexing pawl and the cam, said ratchet pinion being sufliciently long in axial direction to remain in engagement with the pawl during reciprocation of the carriage, a ratchet wheel with reversely faced teeth on said shaft, and a resilient or cushion stop means engaged by one of said teeth to arrest the indexing motion, said stop means being disengaged when the carriage is advanced to close the dies in order not to interfere with the normal action of the die pilots.

8. An automatic die casting machine comprising a single cover die having a parting face and having a sprue passage therethrough, means to eject molten metal under pressure through said sprue passage, a rotatable dial, a plurality of like ejector dies carried on said dial, said dies having die pilots, said dies having ejector pins for ejection in the direction of the axis of the dial, means to move said dial and all of said ejector dies bodily axially toward and away from said cover die for a substantial distance in order to close and open one of said ejector dies relative to the cover die, means to index the dial to cause said ejector dies to mate successively with said single cover die, and means to cause operation of the aforesaid means in properly timed relation, the aforesaid means including a dial shaft carrying said dial and rotatable in a carriage arranged for reciprocation, a ratchet pinion on said shaft, a pawl operating on said ratchet pinion for indexing the dial, a cam for reciprocating the carriage, a motor to drive both the indexing pawl and the cam, a brake drum on said shaft, a brake shoe mounted on said carriage and engaging said drum,

and means operative, when the carriage has been advanced to close the dies, to release the brake shoe in order not to interfere with the normal action of the die pilots.

9. An automatic die casting machine comprising a stationary cover die, a stationary trimmer die located in generally the same plane but displaced from said cover die, a rotatable dial, a plurality of like ejector dies carried on said dial, said dies having die pilots, said dies ejecting in the direction of the axis of the dial, means to move said dial axially toward and away from said cover and trimmer dies in order to close and open the same, means to cause ejection after closing of the dies, means to index the dial to cause said ejector dies to mate successively with said cover die and trimmer die, whereby the castings are trimmed as they are ejected, and means to cause operation of the aforesaid means in properly timed relation, the aforesaid means including a dial shaft carrying said dial and rotatable in a carriage arranged for reciprocation, a ratchet pinion on said shaft, a pawl operating on said ratchet pinion for indexing the dial, a cam for reciprocating the carriage, a motor to drive both the indexing pawl and the cam, a brake drum on said shaft, a brake'shoe mounted on said carriage and engaging said drum, and means operative, when the carriage has been advanced to close the dies, to release the brake shoe in order not to interfere with the normal action of the die pilots.

References (Iited in the file of this patent UNITED STATES PATENTS 859,640 Bright July 9, 1907 1,648,415 McGee Nov. 8, 1927 1,913,945 Morris June 13, 1933 1,931,489 During Oct. 24, 1933 2,243,835 Brunner June 3, 1941 2,515,915 Voigt July 18, 1950 2,568,956 Fienberg Sept. 25, 1951 2,569,083 Wilhelm Sept. 25, 1951 2,762,094 Vieth Sept. 11, 1956 2,830,323 Krebs Apr. 15, 1958 2,848,770 Schuchardt Aug. 26, 1958