US3209417A - Apparatus for assembly die casting - Google Patents

Description

Oct. 5, 1965 w. F. FISHER 3,209,417

APPARATUS FOR ASSEMBLY DIE CASTING Filed March 26, 1965 8 Sheets-Sheet 1 EAR FEED IN VENTOR WILLIAM E FISHER 9202!) 7 ATT'EIINEY:

Oct. 5, 1965 W. F. FISHER APPARATUS FOR ASSEMBLY DIE CASTING Filed March 26, 1963 8 Sheets-Sheet 2- A a 50 I 35 29 3Q 44 4% -34: 0L suns ROTATES TO LOCK 37 53 -r P WHEN CLOSED 82 3g 39 40 6/ INVENTOR WILLIAM E FISHER fax Oct. 5, 1965 w. F. FISHER 3,209,417

APPARATUS FOR ASSEMBLY DIE CASTING Filed March 26, less 8 Sheets-Sheet 3 00 l/2 9s 89 97 l 115 F7618 A +175 [/0 'L I //2 i H9 10a 93 92 H8 J INVENTOR FIG. 7 WILL/AM F. FISHER Oct. 5, 1965 w. F. FISHER 3,209,417

APPARATUS FOR ASSEMBLY DIE CASTING Filed March 26, 1963 8 Sheets-Sheet 4 FIG. /0

INVENTOR WILLIAM E FISHER ATTORNEYS Oct. 5, 1965 w. F. FISHER APPARATUS FOR ASSEMBLY DIE CASTING 8 Sheets-Sheet 5 Filed March 26, 1963 INVENTOR W/I. LIAM F. F ISHE 1? jazz JMX f.

ATTORNEYS Oct. 5, 1965 w. F. FISHER AFPARATUS FOR ASSEMBLY DIE CASTING 8 Sheets-Sheet 6 Filed March 26, 1963 n M m E W WK Oct. 5, 1965 w. F. FISHER APPARATUS FOR ASSEMBLY DIE CASTING 8 Sheets-Sheet 7 Filed March 26, 1963 FIG. 16

FIG. 17

INVENTOR WILLIAM F: FISHER ATTORNEY Oct. 5, 1965 w. F. FISHER 3,209,417

APPARATUS FOR ASSEMBLY DIE CASTING Filed March 26, 1963 8 Sheets-Sheet 8 INVENTOR WILLIAM E FISHER ATTORNEY United States Patent 3 209 417 APPARATUS FOR ASSEMBLY DIE CASTING William F. Fisher, Peterborough, Ontario, Canada, as-

signor to Fisher Gauge Works, Limited, Peterborough, Ontario, Canada, a corporation of Ontario, Canada Filed Mar. 26, 1963, Ser. No. 268,037 13 Claims. (Cl. 2268) This invention relates to die casting apparatus and more particularly to such apparatus for making use of die casting to unite several different components into a permanent assembly.

It is a general object of the present invention to provide novel apparatus for assembly die casting,

More particularly, it is an object of the present invention to provide novel apparatus for automatically assembling a wheel or gear, a central pivot or spindle therefor and a plurality of parallel wires to form a lantern pinion of the unshrouded or cantilever type, by die casting metal about the said parts to immobilize them in proper relation to each other.

An important object of the invention comprises the fixing of a die unit in position after adjustments, and the supplying thereto of all the components of the assembly from various directions without hindering the delivery of die cast-ing material thereto, which latter is accomplished in a single operation.

Another important object of the invention comprises the use of a movable die part in addition to the fixed section so that the gear or wheel may be inserted laterally in a fixed seat, the pinion wires then advanced through the movable die part, to die parts closed, the spindle wire advanced through the fixed cavity part into a guide in the movable part, the casting nozzle advanced to the gate in the fixed die part and metal then injected to complete the assembly with all parts locked in position.

A further important object of the invention comprises the subsequent cutting of the spindle wire within and while the die is closed, and the opening of the die part while holding the pinion wires fixed in relation to the movable die part to withdraw the cast assembly from the fixed die part.

A still further essential object of the invention comprises the cut-otf of the pinion wires during the opening of the die parts, and after re-setting of the cutting portion of the die, the immediate advance of the pinion wire stock to push against the cut-off pinion wires of the assembly to eject the latter from the movable die section now fully separated from the fixed die section.

Included among the more important features of the invention are the following:

The two different methods and apparatus used for feeding the spindle wire through the fixed die part and the pinion wires through the movable die part;

The means for separating the sprue from the cast by rotation of the movable die part during die unlocking and prior to withdrawing casting nozzle;

The electrical heating of the casting nozzle to melt the sprue back into the nozzle; and

The use of a small, secondary casting pot which retracts with the nozzle and is kept full of metal by a pump from a primary melting pot via a chute and under the control of sensing means on the casting pot.

Other and further objects and features of the invention will be more apparent to those skilled in the art upon a consideration of the following specification and accompanying drawings wherein is disclosed a single exemplary embodiment of the invention with the understanding that such changes and modifications may be made therein as fall within the scope of the appended claims without departing from the spirit of the invention.

In said drawings:

FIGURE 1 is a general elevational view of the essential parts of the complete assembly die casting apparatus;

FIGURE 2 is a simplified elevational view, partly in vertical section, illustrating in principle only, the fixed and movable die parts, the melting and casting pots and the arrangement of the spindle and pinion wire feeds;

FIGURE 3 is a vertical central sectional .view on an enlarged scale, through the fixed die part and mostly in elevation a portion of the movable die part in a partly open position;

FIGURE 4 is a longitudinal central section of the gear, pinion, spindle and cast metal assembly which is one form of the product from the method and apparatus of the present invention, shown on a still larger scale;

FIGURE 5 is a side elevation, on an enlarged scale, of the pinion wire feed assembly which is mounted on the movable die assembly shown in its closed position and disengaged from the stationary operating cams therefor;

FIGURE 6 is a view similar to FIGURE 5 but with the movable die assembly fully retracted and cooperating with the stationary cams;

FIGURE 7 is a transverse, vertical section taken on line 7-7 of FIGURE 6;

FIGURE 8 is a transverse vertical section on line 8-8 of FIGURE 5 illustrating the stationary cam mounting arrangement;

FIGURE 9 is a right end elevation of the movable die structure;

FIGURE 10 is a vertical longitudinal section through the movable die assembly on a larger scale than FIGURE 3 and illustrating the pinion Wire guides and cut-oil? means, the section being taken on line 1010 of FIGURE 9;

FIGURE 11 is a front elevational view of the stationary pivot wire feed and cut-off mechanism in position at the end of a wire feed stroke of the actuating piston;

FIGURE 12 is a fragmentary elevation similar to FIG- URE 11, but showing the other extreme position of the piston and feed rolls; f=FIGURE 13 is a transverse section taken on line 1313 0 their drive and holding clutches;

FIGURE 14 is a left end elevation, partially sectioned on line 1414 of FIGURE 11 illustrating pivot wire cut-off mechanism;

FIGURE 15 is a vertical central, longitudinal section taken on line 15-15 of FIGURE 14, but illustrating the spindle wire guide and cut-ofi mechanism associated with the stationary die part, also in section, to disclose the wire shearing arrangement;

FIGURE 16 is a perspective view of the secondary casting-metal pot and its injection nozzle;

FIGURE 17 is a top plan view of the secondary pot and its attached nozzle and illustrates the overflow receptacle;

FIGURE 18 is a central, vertical section through the secondary pot taken on line 18-18 of FIGURE 17 and showing the metal pump incorporated therein and its delivery channels to the nozzle; and

FIGURE 11 showing the pivot wire feed rolls and FIGURE 19 is a longitudinal section through the nozzle structure taken on line 19-19 of FIGURE 17 and showing its incorporated electric heater.

The operation of permanently assembling into a unit of a number of small parts, both accurately and rapidly has long been a requirement for the low cost manufacture of such devices as clocks, meters and the like. In accordance with the present invention both the methods and apparatus for achieving such results in connection with gears or wheels, spindles and lantern pinion trundles are improved where the attachment of the several components to be unitized, derives from die casting about them a sufficient quantity of a relatively low melting point metal to hold the components firmly together. The basic idea is not novel but the present improvements permit simpler and more rapid automation of the whole project.

For an understanding of the apparatus of the present invention a grief look should first be had at FIGURE 4 of the drawings, which illustrates on a relatively large scale the product manufactured thereby comprising a central spindle 20, a plurality of lantern pinion trundles 21 and a relatively large wheel 22, which may be as shown, a gear, a ratchet, an escape wheel or the like. It is preferably a sheet metal stamping of appropriate thickness having a central aperture 23 of greater diameter than that of the pinion. The seven or eight trundles of the pinion are extended through the wheel opening and together with the spindle and the wheel are closed in a die and unitized by a mass of die cast metal 24, which may be a tin, antimony and lead mixture or one of the better known zinc alloys. Indeed, a plastic, in the sense that the term is now used, may also be found appropriate. This binding material is cast about the trundles and pivot wire or spindle and about the center portion of the wheel in a single shot or operation, hardens almost instantly and holds the parts in the positions illustrated with appropriate rigidity and accuracy of spacing. Obviously, the shapes and dimensions shown are arbitrary and may be varied widely with appropriate changes in the shape of the die parts which hold the wires and wheel and form the mold for the cast material.

To further a quick appreciation of the essential features of the invention, FIGURE 2 has been provided to show in a simplified form of the apparatus the principal features, with no attempt to show operating mechanisms or supports and mountings for many of the parts. In this figure the line marked CL is the center line of the spindle or axis of the part to be assembled and from the right along this center line is fed the wire which constitutes the spindle 20 of the assembly shown in FIGURE 4. From the opposite end are fed the plurality of wires or trundles 21 which are to form the lantern pinion, while down the track 25 the gears are gravity fed from a suitable mechanism which separates them from a hopper and delivers one for each casting operation.

At the lower end of track 25 is the fixed member 26 of the die into which the cast metal is injected. It is perforated along the center line for the passage of the spindle wire which is withdrawn from a large diameter coil of such character that the wire does not need straightening. From feeding mechanism, not illustrated, the wire is advanced through the bushing 27 and then passes loosely through the central cavity 28 in the die, which forms the smaller tapered portion of the hub about the spindle as seen in FIGURE 4. Beyond this there is the counterbore 29 forming the enlarged portion of the hub into which the right ends of wires 21 are introduced through and after the gear, which is first introduced by means of slot 30 into a seat appropriately sized to hold it with exact centering with respect to the center line.

The gear is held by the retaining ring 33 until engaged by the head 34 of the removable die part 35, longitudinally slidable and partially rotatable in die housing 36, and which presses it against the left face 32 of the stationary die. The part 34 contains a cavity complementary to the one 29 with which it cooperates in boss 32 and is also perforated for the passage of the wires for the pinion, feed mechanism for which is housed at 37. Upon the closing of the movable die section on engagement With the gear face, and its rotation for locking, hot metal is injected through the gate 38 by moving the nozzle 39, attached to the secondary casting-metal pot 40, upward into close engagement with the gate under the action of the advance and retract mechanism generally bearing reference character 42, which is power driven and timed in an obvious manner. When the nozzle fits tightly into the port and the signal is given that the die is locked the injection plunger 44 is advanced and forces hot die-casting-metal into the cavities in the two die parts and surrounding the inner portion of the gear, the spindle and the embedded sections of the cantilever pinion wires.

The movable die portion now starts to rotate slightly toward its release condition which shears off the sprue where it passes through the port 38 leaving it almost solely in the passage in the nozzle. This nozzle is electrically heated and as the secondary pot 40 is being withdrawn after the sprue has been cut loose, the latter melts and subsides into the pot. During this rotating motion, the shear finger 53 engages a shear arm so that the inner port of the movable die is restricted from rotating while the remainder of the die rotates, thus shearing the pinion wires.

The secondary pot 40 is of small dimension and offset below and to the rear so as not to intersect the center line of the die nor interfere with the introduction of the gears described or others which may be used for a multiple assembly, so a primary melting pot 50 is provided to replenish its supply and this mounts a pump 51 actuated by detecting mechanism, not shown, in the secondary melting pot to keep the latter replenished via the chute 52 and,'thus, maintain the level of the metal in the nozzle substantially at the tip, displacing the usual air space inside the nozzle with metal and contributing to denser casts.

After the casting is completed, mechanism to be later described shears oi? the spindle wire at the proper place, and the movable die part 35 is rotated by its carrier and the finger 53 thereon connected to a separate inner part of the die engages a stop mounted on the housing while the outer part of the movable cavity unit continues to rotate to fully unlock the die. Thus, the inner part is restrained causing the pinion wires to be sheared at cut-off points which will be later described in greater detail. A cam on the die housing then resets finger 53 to realign the pinion wire holes in the two cutting parts, one of which determines the length of the overhang of wires 21. The die now commences its opening stroke, and mechanism, to be later described, advances the fresh pinion wires into the removable die cavities to a predetermined extent and these advancing wires push against those in the just cast assembly ejecting it from its cavity for delivery for further use by a chute or by automatic mechanism which picks it up and orients it. This latter mechanism forms no part of the present invention, but does include detecting means indicating the presence of the removed cast assembly and initiating the operation of introducing a new gear and reclosing the die along with the other operations already described.

It will be clear from the above that the arrangement in general is such that both ends of the dies are left clear at all times, for the introduction of the spindle and pinion wires from opposite ends, and, that most of the side areas about the two parts of the die are available for the introduction of gears and similar parts, making the machine of more or less universal adaptability.

For a more complete illustration of the invention reference should be had now to FIGURE 1 which includes most all of the essential components mounted on a base from which the column 60 supporting the basic mechanism and the column 61 supporting the metal pot 50 arise. Insofar as possible the reference characters used on FIGURE 2 have been repeated on this figure, however, in this figure some elements, which were visible in FIGURE 2, are completely enclosed or hidden behind others which were illustrated in the more simplified form.

In FIGURE 1 the reference character 62 designates the mechanism which accepts gears from a hopper or container, not shown, and feeds them one at a time down the track 25, as previously explained. The pivot wire 20 as seen to the right passes through cleaning mechanism 63 and the multiple pinion wires 21, moving side by side in a flat band from the left, extend through the cleaning apparatus 64 which insures removal of the grease, dirt, scale and the like so that they will not slip in their embedment of the casting material. The important remaining components illustrated in FIGURE 1 will be referred to from time to time in connection with detailed showings of many of the parts.

Referring now to FIGURE 3 which illustrates on a large scale the stationary die or casting mold and portions of the movable die, partially withdrawn therefrom, it will be seen that the former 26 comprises a block of metal bored on the axis or center line of the die system and having the mold compartment 28 therein as well as the narrow gate 38 entering the largest portion of this central compartment adjacent the left face of boss 32 formed integral with the number 26. Below the gate is the flared or conical passage 38' which guides the nozzle of the casting pot. The face of boss 32 is covered with a locating ring 66 of suitable material bored to receive the gear 22 when the die closes and notched to catch the gear when delivered from the feed slot 30 heretofore referred to into which the gear is fed. The bore is sized and arranged to properly center the gear. This locating ring is held in position and the movable die member guided by the retaining ring 33 housed in the larger ring 33 forming the leading or nose end of the stationary housing or guide 85 for the movable die assembly 35. The retaining ring has a central aperture 67 through which the circular nose 68 of the movable die enters so that its flat face 69 presses the gear against the flat face of the boss 32 on the stationary die, whereby the gear is engaged throughout all of its area, except that to be occupied around its bore by the casting metal, and is tightly clamped so that no casting metal may flow over its faces. The nose 68 on the end of the movable die carries a replaceable external wear ring as shown.

Reference should now be had to FIGURES 9 and 10, shown on a larger scale, for the construction of the movable die and cavity member. The face 69 thereon, which is received against the face of the stationary die member, has cavity 70 opening therethrough to form the molded material about the left face of the gear and the inner ends of the pinion Wires. It is fitted with a non-rotatable insert 71 having a plurality of passages 72 arranged in a circle to receive the pinion wires which first pass through corresponding passages 73 in the partially rotatable assembly 73 to the left thereof. Thus, when the passages in these parts are aligned the wires may be introduced simultaneously to pass through openings 72 to the prescribed distance through and beyond the wheel into the stationary die to later be encased in metal as seen in FIG- URE 4. This insert 71 also has the larger central passage 74 to form the base around the pivot wire extension, the bare left end of which extends into bushing 75 fitted into the partially rotatable central core section 76 through which the passages 73 :also pass. The insert 71 is of hardened metal as is at least a part of the central core 76, and, at their meeting faces 7-7, relative rotation of the parts 71 and 76 serves to simultaneously sever all of the cantilevered pinion wires, the length of the cantilevered extensions being determined by the thickness of the insert 71 whose right face forms the left end of the cast. The

6 v central core 76 is mounted in a larger ring 78 which at 79 is journalled for limited rotation in the carrier head 35.

Motion is imparted to it by arm 53 secured thereto by the several pins and screws illustrated. The arm 53 extends below the outer cylindrical surface of the part 35 and its carrier slide 81, and has a rounded head, as seen in FIGURE 9, which in the closed position of the die assembly lies beside the hinged finger 80 shown in FIGURE 1, so that when the unlocking operation starts, by the clockwise (FIGURE 9) rotation of slide 81, the arm 53 is prevented from rotation by engagement with the side of finger 80', whereby the die part 76 is held stationary while the outer portion carrying the inset 71 achieves a partial rotation so that simultaneous cutting of all the pinion wires takes place at the plane 77.

As the movable die assembly is retracted, after unlocking, toward the position seen in FIGURE 1, the cam 82 returns arm 53 to its normal position in the die so that the openings in the die part 76 align with those in the insert 71 permitting feed of fresh pinion wires, by mechanism to be later described, because of the proper alignment of the holes through which they pass. On the return stroke the arm 53 is so positioned that it strikes the finger 80', shown in FIGURE 1, but the latter is hinged to permit forward motion as indicated in dotted lines to allow 53 to pass. As soon as the slide 81 and its carrier parts of the movable die advance and rotate counterclockwise, to lock the die sections together, the arm 53 moves laterally to permit finger 80 to resume its normal position, by spring action, ready for the next cutting operation.

FIGURE 7 shows the carrier slide 81 for the movable die, slidably and partially rotatably mounted in the irregularly shaped dotted guide member 85, which is stationary on the machine except for initial adjustments. Slide 81 is reciprocated by the rod of a piston, working in a cylinder 86 which is only visible in dotted lines in FIG- URE 1, on the left, being hidden behind the pinion wire cleaning mechanism 64. The movable cavity and its housing 35 are secured together and supported on the left end of the main slide 81. The assembly 35 is readily removed from 81 by lifting about inch and then withdrawing to the right. Such quick release is necessary for threading the pinion wires through their holes 72 and 73 in the cavity and housing parts.

FIGURES 5, 6, 7 and 8 illustrate the complete mechanism for feeding the pinion wires. However, the actual feeding mechanism including the feed rollers for advancing the wires is carried in and by the movable die unit carrier 81 as seen in FIGURE 7. This assembly designated 87 in FIGURE 5 cooperates with a stationery cam system 88, mounted on the main frame 89 of the machine in respect to which the carrier 81 for the movable die components slides longitudinally from right to left and back under the action of the pneumatic or hydraulic cylinder described.

As seen in FIGURE 5 the pinion wires 21 to the far left are unwound from the reel and pass into the pinion wire guide 90, supported in the movable die unit carrier 81, and emerge from its right end through the guide member 90 positioning them in a flat band, side-by-side, so that they pass betwen the serrated surfaces of upper feed roller 91 and lower feed roller 92. As seen in FIGURE 7 the lower feed roller is circumferentially channeled or grooved at 93, wide cough to accommodate the seven or eight pinion wires in a flat band. These are frictionally engaged by the extending rim 94, on the upper feed roll, which fits in the groove 93 and presses tightly against the wires to feed them as the rolls are rotated. The rolls are geared together for simultaneous operation by means of the inter-fitting gear teeth 95, best seen in FIGURES 5 and 6.

FIGURE 7 shows the mounting for the upper gear and its feed roller 91, which are integral, to comprise a dual set of ball bearings 96 the inner races of which are mounted on a spindle 97, which is carried in a boss on arm 100 of a bell crank lever pivoted at 101 on a stud secured in plate 98, which latter is secured directly to the rear wall 99 of a cavity in the main slide 81. The other arm 102 of the bell crank lever is connected to be tensioned by movement of the screw 103 so as to force the upper roller with its rim 94 tightly down onto the wires in the groove in the lower roller whereby feed of these wires toward the right in respect to slide 81 is achieved when the lower roller is given a partial clockwise rotation, as will now appear.

The lower roller 92 is supported by needle bearings 105 rolling on an enlarged portion of stud 106 secured in plate 98 as shown. This lower roller has an elongated sleeve 107 extending toward the left over two clutch elements, one 108 fixed to shaft 106 rotatable in respect to shaft 106 under the action of a cam operated roller 110 mounted near the outer end of arm 111 attached to 109, the whole assembly being held together by lock ring 112. Each of the clutches 108 and 109 is of the so-called roller variety with the rollers on clutch 109 being so cammed outwardly by surfaces thereon as to engage the sleeve 107 and drive the wire feed roller 92 when arm 111 is rotated clockwise as viewed in FIGURES and 6, such action being achieved by the roller engaging the surface 112 of the lower cam which is stationary in cam unit 88 referred to previously. Such cooperation occurs when the piston and cylinder referred to at 86 in FIGURE 1 move the die main slide 81 toward the left.

This action feeds pinion wires simultaneously to the right, in respect to the carrier, it being remembered that their ends are already in the small bores 73 in the movable die portion and have been cut off at the plane 77 therein as seen in FIGURE 10. The amount of movement effected by the cam follower riding on cam 112 is adjusted to be correct for the desired lengths for a set of pinion trundles, which are to be cut off after the next casting operation is completed and this amount is actually governed by the upper return cam.

On the return stroke of die carrier 61, cam follower 110 is moved back to the position illustrated in FIGURE 5 by the lower surface 113 of the upper cam as will be obvious. On this return the roller clutch 109 releases so as not to withdraw the wires. However, the clutch 108 which has permitted the wires to move to the right now locks them so that they move forward with the carrier and are withdrawn from the reel on which they are wound. This clutch insures that the portions of the wires which extend to the right of the feed rollers are not pushed back as a result of any friction with clutch 109.

To facilitate service on the parts just described and others which may be behind the cams, and to facilitate changing the latter, the support for the two cams is a substantial effort being used to pull it down when the plunger will be pressed in against the spring and the blade may be lowered.

With an understanding of the feed mechanism for the pinion wires, but little explanation is needed for the one used to feed the single pivot wire from the other end of the machine. It differs in principle only in that it is stationary in respect to the stationary die member and wire movement is achieved by directly rotating the upper feed roll by a piston and cylinder arrangement. Looking now at FIGURES 11, 12 and 13 the pivot wire enters in FIGURE 11 from a reel at the right and passes between feed rollers 120 and 121. In this case the upper roller is grooved as at 122, and is the driven one, while the lower roller has the rib or flange thereon for clamping the wire in the bottom of the groove. are geared together by 123 and 124. The upper roller is The upper and lower rolls mounted on shaft 125 secured to plate 126 which is adjustable in fixed frame 127 for obvious reasons. The guide tube 128, FIGURES 11 and 12, guides the pivot wire to the nip between the feed rollers, and some distance beyond them to the left, the wire enters the movable cutoff bushing 129 the left end of which is engaged in recess 130 against the stationary cut-off bushing 27 in the right face of stationary die member 26, as seen in FIGURES 3 and 15.

The lower feed roller is mounted on an arm 131 fulcrumed at 132 and having the bell crank arm 133, with adjusting mechanism 134 to properly tension the rollers against each other. The upper roller has a dual clutch system exactly as described in connection with the pinion wire feed rollers and the inner clutch member 135 is given its partial rotation and return by lever 136, line 137 (FIGURE 11) and piston rod 138 to which the link is pinned at 139. The rod oscillates in a cylinder, under the action of pneumatic or hydraulic pressure in a conventional manner, the stroke being from the position shown in FIGURE 11 to that shown in FIGURE 12, moving the roller through an angle of approximately 90. The stroke just completed in FIGURE 12 is the one in which the drive clutch releases, and then as the piston withdraws the rod to the position shown in FIGURE 11, roller 121 moves in a clockwise direction and feeds the pivot wire toward the left into both parts of the die.

FIGURES 11, 14 and 15 show that bushing 129, through which the pivot wire is fed into the stationary die member, is eccentrically bored for the passage of the pivot wire, although it is journalled for rotation about its own center axis in counterbore 30 in stationary die 26. The cut-01f bushing 129 is actually made in two halves to facilitate manufacture and is held together by beingpressed in sleeve 140. An arm 141 is secured to sleeve as seen in FIGURES 14 and 15 and is actuated by being pivoted to piston rod 142 actuated by a piston in cylinder 143. The hole in the bushing 129 through which the pivot wires passes is normally aligned with the hole in the pivot wire guide and cut-off bushing 27, seen in FIGURE 3, as well as in FIGURE 15, and this condition exists when the wire must be fed toward the left before each casting operation.

It will be remembered that among the important features of the present invention is an arrangement wherein wires may be fed into the two-part casting die from each end thereof either singly on the die axis or in multiple surrounding the axis. The die is partially rotatable about this axis for locking, wire cutting, sprue removal, and the like. Since the wires extend from coils supported at remote points at opposite ends of the machine, it is required that none of the working parts of the apparatus project across the axis of the dies or sufficiently close thereto to interfere with the wires being fed to form, for instance, the axle of a gear and a lantern pinion, which form portions of the finished casting.

FIGURES 1 and 2 illustrate generally the arrangement of a main or holding metal pot 50 in which a large quantity of the casting metal is melted in any desired manner and held in reserve for delivery through the action of a pump mechanism 51 and the spout 52 into a secondary casting-metal pot 40, as best illustrated in FIGURE 2, from which it is delivered through the action of a pump plunger rod 44 and an actuating cylinder through passages in the injector nozzle 39 and is finally injected thereby into the die cavity when the nozzle is inserted into the gate 38 in the stationary portion of the die. This gate is conical as best illustrated in FIGURES 2 and 3 and is vertically below the axis of the pivot wire 20. A common plane will contain the axis of the gate, the axis of the die and the axis of the injection nozzle.

Referring now to FIGURES 16 to 19, inclusive, the secondary casting-metal pot 40 and its associated injector nozzle 39 and accessory devices are illustrated in detail.

9 The diameter of this pot is largely determined by the stroke of the pot assembly since it is preferred that it remain beneath the spout 52 at all times. In the perspective view of FIGURE 16 the secondary pot 40 is seen as including a housing 152 extending radially from the lower portion thereof to receive Various electrical devices including electric heaters for maintaining the metal delivered to the secondary pot, from the principal or melting pot at 50, in a continuously molten condition. The resistance coils of the electric heaters are not illustrated, but are positioned directly below the bottom wall of the pot in order to be most effective on the casting metal, which melts at a relatively low temperature. Also housed within the compartment 152 may be detecting means for determining that the pot is sufficiently depleted to require operation of the pump 51 for delivery from the main supply.

The secondary pot 40, as viewed in FIGURES 16, 17 and 18 is provided with an overflow spout 154 directed to the rear, and, as seen in FIGURES 17 and 18, it overhangs the waste receptacle 155 which receives any overflow in case of overfilling, the intention being to maintain the level, as shown in FIGURE 18, substantially at the height of the tip of nozzle 39 so that the metal is always right at the tip ready for delivery thus avoiding air injection.

The pot has cast integral with it a side arm 156, inclined toward the gate 38 in the stationary part of the die as viewed in FIGURE 3, and this serves to carry the nozzle tip 39 and its protective cover 157 which extends over it and has a base flange 158 extending laterally secured in a copper closure plug 159 which closes the upper end of the cylindrical copper sleeve 160 which receives the electric heating cartridge 161 fitted into bore 160 and serves to maintain the metal molten at all times in the passages leading to the nozzle 39. Sleeve 160 is housed in the open ended bore 160' beside and slightly inclined to the nozzle axis.

The passages just referred to are seen in FIGURE 18 at 162 and 163, the latter being on the axis of the nozzle and the former extending at right angles thereto from the injection pump whose cylinder extends vertically downwardly from the center of the floor of the pot 40, as best illustrated in FIGURE 18.

The pump illustrated in FIGURE 18 comprises a headed sleeve 164 tightly fitting a bore in the center of the base of the pot in which is fitted the actual pump cylinder 165, closed at its lower end by plug 165. Sleeves 164 and 165 have bores aligned with passage 162. The inner sleeve closely receives the piston plunger 44, previously referred to, which is moved under the action of an air cylinder 150 as seen in FIGURE 2. Liquid metal obtains access to the space beneath the plunger by way of the longitudinal channel 166 in sleeve 164 which opens at its upper end beneath the surface of the molten metal and at its lower end delivers through bore 167 in sleeve 165. With the piston, as shown at the top of its stroke, metal will flow by gravity to fill the chamber beneath the piston and as soon as the piston starts to descend it shuts ofl? bore 167, and metal is forced through passages 162 and 163 to issue from the tip of nozzle 39 in a known manner.

'Arranged in the pot base on either side of the pump system are four holes 170, disposed horizontally and.

designed to receive electric heating elements, similar to the one shown at 161, accessible through the opening 152 previously described. They serve not only to heat the bottom Wall of the pot 40 to keep the metal therein molten, but serve to heat the pump and the fiuid passages in the extension 156 to insure the metal remaining molten, and in this latter function, are assisted by the heater 161 adjacent the upwardly extending passage 163 in the nozzle extension. It should be appreciated that thermostatic devices, one of which may even be housed in one of the bores 170 will control the supply of current to these heaters.

A number of holes 171 seen in FIGURES 16, 17 and 18 are arranged around the nozzle structure and between it and the edges of the extension flange 156 to substantially reduce the thermal-conductivity toward the outer portions of the flange and thus curtail loss of heat, which might tend to cause congealing of the metal in some of the passages. In a like manner deep saw cuts as seen at 172 may serve to isolate the heated sections of the flange from the peripheral areas thereof, which latter may serve for mounting the pot assembly on a slide and for holding insulating lagging and a cover as seen at 175 in FIGURE 2.

FIGURE 2 also illustrates in some detail the stationary guide member 176 of generally L shape and fitted with appropriate gibs and slides to guide the combined pot and nozzle assembly in its reciprocatory motion under the action of the actuating mechanism 42. Thus, the pot travels with the nozzle as the latter is advanced into the gate for injection and subsequently retracted after each such operation, in order that the sprue which has been cut off, as previously described, by the opening of the dies will be withdrawn on the tip of the nozzle and will have time to melt down into the opening therein under the action of the electric heater.

In the sequence of operations of forming an assembly which is a product of this invention, as soon as the pot nozzle has advanced to the die and metal is injected, the cylinder 143 is energized so that eccentric bushing 129 is partly rotated through the action of the piston, cutting off the pivot wire at the surface by a shearing action through the eccentricity of the bushing hole in respect to the cylindrical surfaces of the guide and the bore in which it fits. The movable die is now free to unlock by its rotational action and then is withdrawn, concentrically of its center and the guide hole therein for the far end of the pivot wire facilitates this.

The nineteen figures just described disclose all of the essential features of construction and the method of operation as outlined therein, except for the sequencing of the various steps of the power mechanisms for achieving them. Many ways remain for bringing about the desired results at the proper time and these may include such things as timing clocks for determining sequence and dwell in the various stages, but preferably an electronic sequence control panel is used. On the other hand, use may be made of light beams interrupted by the movements of parts, the delivery of the finished product and so on for activating photoelectric cells which then energize electric motors, magnets and the like for carrying out the various transitions and sequential operations. All of these are subject to so many variations that even a specific showing of any one of them seems superfluous, for the above descriptive matter includes statements of the operations which are to take place and in what order without in every case defining the actuating and sequencing means. Hence, such expressions as means to move, a power device to actuate, etc. as used in the claims are believed to be adequate.

I claim:

1 Assembly die casting apparatus including in combination; a two-part separable die having mating casting cavltres in the two parts and a chamber for clamping a wheel with the periphery of a central aperture therein extending into said cavities; one of said die parts being fixed and the other die being adapted for both rotation and reclprocation, means associated with the fixed die part to axially insert a spindle wire for said wheel through that par-t and beyond the cavity in the other, means associated with the'movable die part for inserting a plurality of wires to form pinion trundles into the cavity therein; a disc insert perforated for the pinion wires secured to the face of the movable die part, a gate in said fixed die part entering said die cavity, a casting pot having a nozzle, means to advance said pot to enter the nozzle into said gate, cutting means for the spindle wire adapted for actuation after the cast, locking means for the die parts actuated by partial rotation of the movable die part whereby unlocking rotates the cast with the movable die part and severs it from the sprue in said gate and means to withdraw the movable die part to release the cast assembly.

2. The apparatus of claim 1 in which said insert is of a thickness to determine the length of protrusion of the pinion trundles from the cast, a shaft axially aligned with said disc and perforated to guide said pinion wires into the disc perforations, and means to rotate said shaft relative to the disc to cut off the pinion wires from the trundles in the disc after the die has begun to rotate to unlock.

3. The apparatus of claim 1 in which the fixed die part has a spindle wire guide bushing leading to the cavity therein, the outer face of said bushing determining the length of spindle projecting beyond the cast, a spindle wire guide tube having an end abutting said bushing and a spindle Wire passage normally aligned with the bushing opening, means in said fixed die part forming a bearing for said guide tube eccentric to said passage and means to partially rotate said guide tube to cut-off the spindle wire at said bushing face.

4. The assembly die casting apparatus of claim 1 in which said spindle wire enters from one end along the axis of the die parts, and the pinion wires around the same axis from the other end, a wheel feeding mechanism above the die parts, a wheel chute leading from said apparatus to said chamber in the stationary die part, said chute extending substantially radially to said axis, the apparatus being so mounted that the said axis is inclined downwardly toward the spindle wire entry end to hold the wheel in its chamber after delivery, and means on the movable die part positioned to enter said chamber and clamp the wheel between the die parts prior to metal injection.

5. Assembly die casting apparatus including in combination; a two-part separable die having mating casting cavities in the two parts and a chamber for clamping a wheel with the periphery of a central aperture therein extending into said cavities; one of said die parts being fixed and the other die being adapted for both rotation and reciprocation, means associated with the movable die part for inserting a plurality of wires to form pinion trundles into the cavity therein; a spindle wire guide bushing in the fixed die leading to the die cavity, the outer face of said bushing determining the length of spindle projecting beyond the cast, a spindle wire guide tube having an end abutting said bushing and a spindle wire passage normally aligned with the bushing opening, means to feed spindle wire to said guide and beyond the cavity in said fixed die part including a pair of feed rolls geared for simultaneous rotation, groove and land guide means on said rolls for said wire, power means to rotate said rolls including a one-way clutch interposed between the power means and rolls, and a locking clutch between said rolls and a fixed part to prevent retrograde rotation of the rolls when the movable die part is advanced to meet the fixed part.

6. Assembly die casting apparatus including in combination; a two-part separable die having mating casting cavities in the two parts and a chamber for clamping a wheel with the periphery of a central aperture therein extending into said cavities, means associated with one of said die parts to axially insert a spindle wire for said wheel through that part and beyond the cavity in the other, means asociated with the other die part for inserting a plurality of wires to form pinion trundles into the cavity therein, one of said die parts being reciprocable from a closed position with the other to a wide open position for cast discharge, a longitudinally reciprocable carriage for said movable die part, means for feeding a plurality of pinion wires simultaneously into said movable die comprising a pair of geared together feed rolls, groove and land guide means on said rolls for said wires, means rotatably mounting said rolls on said carriage, a lever for advancing said rolls to feed said wires, a cam follower on said lever, a one-way clutch interposed between said lever and rolls, a locking clutch between said rolls and a part fixed to said carriage to prevent retrograde rotation of the rolls when the movable die part is advanced to meet the fixed part, and stationary cam means to move said follower when the carriage moves in either direction.

7. Assembly die casting apparatus, in combination, a die including a stationary part having an axial port for a spindle wire, a casting cavity connected with said port, a wheel seal against a face terminating said cavity, a wheel chamber and entry slot adjacent said face, and a gate entering said cavity from beneath on an axis inclined to the port axis and the plane of said face and said port axis being inclined downwardly a few degrees from the horizontal to hold a wheel in said seat by gravity.

8. The apparatus of claim 7 in which there is a movable die part having a die cavity adapted to complement the first cavity through an opening in said wheel, a plurality of entry ports in the movable part arranged around the axis of said first port for the entry of pinion Wires, a guide hole in said movable part beyond said cavity therein for said spindle wire, a carriage for said movable die part adapted to be reciprocated to move the second die part to meet the stationary part for casting and withdrawn to release a completed cast assembly.

9. The apparatus of claim 8 in which means is provided to rotate the carriage to lock the die parts together for casting, means to rotate the cast assembly with the carrier on unlocking rotation to cut off the casting sprue at the gate entry.

10. The apparatus of claim 8 in which means is provided to rotate the carriage to lock the die parts together for casting, a disc in the movable die having ports of predetermined length to provide cast free cantilevered trundles from said wires for said pinion, pinion wire guide means in said die having passages normally aligned with said ports and means to prevent rotation of said guide means with the die on unlocking to thereby cut off the pinion wires at the meeting faces of said disc and guide means resulting from the relative rotation of the disc and guide means.

11. The apparatus of claim 10 in which stationary cam means is provided to 'return said guide means to passage port alignment as the carrier is Withdrawn.

12. A secondary die casting-metal pot assembly for receiving molten metal from a primary melting pot including in combination; an open topped pot having a base housing, a centrally disposed delivery pump and surrounding heaters, said pump having a vertical plunger, means mounting said assembly to advance and retract on a surface inclined to about 45 degrees, a flange extending laterally from said base and generally parallel to said surface, a nozzle on said flange on an axis parallel to said surface, a metal nozzle cover positioned around said nozzle, an overflow spout for said pot, said nozzle being connected to said pot by a passage and elevated to the level of said spout, means to maintain the level of metal in the pot substantially to the spout tip, said pump being arranged in said passage and means to heat said base and said spout.

13. A movable secondary die casting-metal pot assembly for receiving molten metal from a primary melting pot, including in combination; a melting pot formed of metal with an open top, an overflow lip extending laterally from the pot to limit the level of molten metal therein, a catch basin positioned and sized to be beneath said lip in all positions of the secondary pot, a base for said pot, heaters embedded in said base to maintain the casting metal molten, a pump in said base between said heaters and having a vertically reciprocable plunger, a flange extending laterally from said base opposite said lip and inclined substantially 45 degrees to the vertical, a nozzle tip on the upper edge of said flange terminating substantially at the overflow level of said pot, a passage containing said pump extending from the bottom of the pot to 13 14 said nozzle tip, a bore in said flange adjacent said nozzle 782,869 2/05 Neureuther 22-58 and the passage leading to it, a metal sleeve in said bore 806,359 12/05 Neureuther 2258 XR closed at its upper end, a metal nozzle cover telescoped 844,389 2/07 Neureuther 22--58 over said nozzle and having a base flange engaging the 867,834 10/07 Neureu-ther 2258 top edge of said lateral flange and extending over said bore 5 2,660,769 12/53 Bennet 22-70 and a fastening securing said base flange to the said closed 2,717,433 9/55 McGervey 22-70 end of said sleeve. 3,137,045 6/64 Sunday 22-68 References Cited by the Examiner I. SPENCER OVERHQLSER, Primary Examiner.

UNITED STATES PATENTS 10 MARCUS U. LYONS, Examiner.

355,624 1/87 Stahlberg 22-58

Claims (1)

1. ASSEMBLY DIE CASTING APPARATUS INCLUDING IN COMBINATIOIN; A TWO-PART SEPARABLE DIE HAVING MATING CASTING CAVITIES IN THE TWO PARTS AND A CHAMBER FOR CLAMPING A WHEEL WITH THE PERIPHERY OF A CENTRAL APETURE THEREIN EXTENDING INTO SAID CAVITIES; ONE OF SAID DIE PARTS BEING FIXED AND THE OTHER DIE BEING ADAPTED FOR BOTH ROTATION AND RECIPROCATION, MEANS ASSOCIATED WITH THHE FIXED DIE PART TO AXIALLY INSERT A SPINDLE WIRE FOR SAID WHEEL THROUGH THAT PART AND BEYOND THE CAVITY IN THE OTHER, MEANS ASSOICATED WITH THE MOVABLE DIE PART FOR INSERTING A PLURALITY OF WIRES TO FORM PINION TRUNDLES INTO THE CAVITY THEREIN; A DISC INSERT PERFORATED FOR THE PINION WIRES, SECURED TO THE FACE OF THE MOVABLE DIE PART, A GATE IN SAID FIXED DIE PART ENTERING SAID DIE CAVITY, A CASTING POT HAVING A NOZZLE; MEANS TO ADVANCE SAID POT TO ENTER THE NOZZLE INTO SAID GATE, CUTTING MEANS FOR THE SPINDLE WIRE ADAPTED FOR ACTUATION AFTER THE CAST, LOCKING MEANS FOR THE DIE PARTS ACTUATED BY PARTIAL ROTATION OF THE MOVABLE DIE PART WHEREBY UNLOCKING ROTATES THE CAST WITH THE MOVABLE DIE PART AND SEVERS IT FROM THE SPRUE IN SAID GATE AND MEANS TO WITHDRAW THE MVABLE DIE PART TO RELEASE THE CASE ASSEMBLY.

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