US2818159A - Sealing head orienting apparatus - Google Patents

Description

Dec. '31, 1957 E. E. YEO ETAL 2,818,159

SEALING HEAD ORIENTING APPARATUS Filed Aug. 17, 1955 3 Sheets-Sheet 1 INVENTORS: EANEJT E. YEO DAV/0 P BROWN JTTORNEK Dec. 31, 1957 E. E. YEO ETAL 2,818,159

SEALING HEAD ORIENTING APPARATUS Filed Aug. 17, 1955 s Sheets-Sheet 2 ERNEST E. YEO DAV/D F. D/POW/V BYW JTTORNEY Dec. 31, 1957 E. E. YE IO ETAL SEALING HEAD ORIENTING APPARATUS 5 Sheets-Sheet 5 Filed Aug. 17, 1955 INVENTORS, 5mm E. Y0 0/11 10 mow/v BY M,

1! TTOR NE Y SEALING HEAD ORIENTING APPARATUS Ernest E. Yeo, Wenham, and David P. Drown, Beverly, Mass., assiguors to Sylvania Electric Products Inc., Salem, Mass., a corporation of Massachusetts Application August 17, 1955, Serial No. 528,977

4 Claims. (Cl. 198-33) This invention relates to automatic machinery for manufacturing electric lamps and the like, and particularly to machines in which the lamp is rotated during a portion of its travel in the machine and the rotation stepped during another period of the travel. Such action generally occurs in apparatus for sealing a flared glass stem to the open neck of a lamp bulb as a closure member therefor. The bulb and stem are rotated together during the first portion of the sealing operation and the rotation is afterward stopped for the application of a mold to shape the seal.

However, the lamp must be stopped in a particular orientation, because lead-in wires ordinarily extend outward from the stem, and their position must be fixed for subsequent operations on the lamp, such as the bending and cutting of the wires, the threading of a wire through a contact base, and the soldering, welding or otherwise affixing of said wires to the base contacts. The orientation is additionally important when a fuse is used in one lead-in wire, because the lead-in wire containing the fuse generally needs to be attached to a particular one of the base contacts.

The stem, usually called a mount when it includes lead-in wires and a filament connected thereto, can be received from a previous machine in a particular orientation, and the sealing apparatus must then control the orientation in which the lamp after scaling is delivered to subsequent apparatus for performing additional operations upon it. In this way, the orientation of the lead-in wires can be controlled throughout the lamp-making process, thereby making possible the complete automation of lamp-making machinery from the feeding of the bulbs, stem flare, lead-in wires, exhaust tube and filament, to the removal of the completed lamp from the machine. The speed at which lamp-making machines operate can thus be greatly increased in such an integrated unit, because of the elimination of manual operations such as feeding of parts, threading of lead-in wires through the base, and transfer of lamps or parts from one machine to another.

In an integrated lamp-making unit, a series of operations are performed successively on the lamp parts at a series of fixed positions or stations, the machine indexing from one station to another. In such a case, the time of dwell in each station is determined by the longest time of dwell necessary in any station. The molding station is one of the stations requiring the longest dwell, because of the large number of successive steps performed there, and because sufficient time has to be provided for the glass to solidify in the mold so that it will retain its shape when the mold is removed.

It will therefore be readily appreciated that even slight reductions in the time required for the molding operation can effect substantial improvements in production rates. Thus, in a sealing machine requiring eight-tenths of a second for each indexing motion and two seconds of dwell or a total time of 2.8 seconds from the start of "ice one index to the start of the next, production will be at the rate of 1285 units per hour on a single index machine. If the dwell time is reduced by four-tenths of a second, a sealing machine single-indexed every 2.4 seconds will produce at the rate of 1500 units per hour, a net gain of 215 units per hour.

The holder for the bulb and mount on a sealing machine is generally referred to as a head, and heretofore orienting devices for such heads have been located at the molding station, with a consequent delay between the arrival of a head at the molding station and the closure of the mold. The delay was necessary to permit the head to be stopped in position for molding. To avoid such delay, the head-orienting device can be located at the station preceding the molding station so that the head is already oriented when it arrives at the molding station. However, this practice is unsatisfactory when conventional head-stopping devices are used at the head-orienting station.

In the usual mechanism of that type, the head is stopped by the engagement with a fixed track of a projection on the spindle to which the head is attached, and this would stop the rotation of the head relatively early in the dwell at the head-orienting station. Hence if burners were provided at that station, the heat therefrom, instead of being distributed around the circumference of a rotating lamp neck would be concentrated on a small portion of a fixed lamp neck, with consequent damage to the lamp. On the other hand, the omission of burners from the head-orienting station would allow the glass to cool, losing the plasticity required for molding.

The present invention overcomes both such difficulties by allowing the heads to rotate until the latter part of the dwell time at the head-stopping station, and only then, ending the rotation. In the particular embodiment later described, this is accomplished by a cam-actuated finger which engages a projection on the head when the rotation is to be stopped. A short, movable track-like guide then engages a flat on the head to insure proper orientation after the head is stopped. On indexing of the machine, the fiat leaves the movable track member, to ride along a fixed track which maintains orientation during further movement of the sealing head.

Although the speed of the machine, in the sense of the number of stations through which a lamp or its parts is moved per hour, is limited by the dwell time required in the station of longest dwell, we have found that the number of lamps produced per hour can nonetheless be increased greatly by having a given operation performed on two or more lamps simultaneously, and then indexing the machine correspondingly through two or more stations at once. We have found that the performance of a particular operation upon two lamps simultaneously, with consequent double-indexing, that is, indexing through two stations at a time, is especially effective in cooperation with automatic apparatus for transferring lamps from one machine to another during manufacture. Some aspects of the invention can be used with the single-indexing customary in the art, but double-indexing greatly increases the speed of production, permitting a production rate of 3000 lamps per hour, for example, with only 1500 indexing motions. The usual single-index machine would only produce half as many lamps with the same number of indexing motions.

In double-indexing machines, a so-called lost-motion mechanism can be used in the linkage which actuates the movable track members to maintain fixed orientation of heads leaving the station while allowing heads arriving at the station to continue rotating. The burners directed onto the lamp neck to heat the same, can therefore be continued in operation without damage to any particularv spot on'the-lamp, because-the rotation distributes-the heatover the circumference of the bulb neck, and is not stopped until just before the bulb leaves the station.

Further objects and novel features of our inventionwill be-cl'arified' from'adetailed descriptionofa preferred embodiment of our invention with particular reference to the accompanying drawings in which:

Figure 1 is a plan view of our apparatus shown ad'- jacent a segment of a sealing machine turret;

Figure 2 is a view'of our apparatus in side elevation taken along line 22 of Figure 1;

Figure 3- is a plan view of our apparatus inenlarged scale taken along line" 33' of Figure 2;

Figure 4- is' a fragmentary end view of'our apparatus showing bell-cranks for actuating; arresting fingers and movable track members;

In Figure 1-, several sealing heads indicated at' 21 and each comprising a bulbseat 17 supporting" a lamp 18 and in" turn supported hy'a pair of posts 19', are rotatably v mounted at the periphery of a sealing'm'achine" turret' indicated at 20. For convenience of reference; the stations occupied by the various heads 21 in Figs. 1 and 3 have" been identified by letters A" through H; It" is believed thatthe operation of our apparatus will b'e more clearly understood if it is first explained that turret 2'0- employs a double index motion, that is, heads 21" are" moved eachtime a distance equal to-the space between alternate head's. Thus the head 21 shown atstation-A will bem'ovedsuccessively to stations C, E, G, etc:, while" thehead-ZI shown at station'B" will beindexedin turn to stations D; F, H, etc. A roller chain 22 suitablydriven in a manner now shown is in engagement with a sprocket 23" on each head 21 at station A throughE'in the drawings and serves to rotate the heads 21" in a counterclockwisedirection (Figs. l3) through a slip clutch 9' (Fig. 2). Itis intended that molding apparatus not shown, but of a type'used in the art, be provided at'stations'F andG; It will also beunderstoodthat'suitable" burners'are furnished-at stations Dand E.

The general arrangement of our apparatus shown at stations'D'and E which'precede'molding stations F and 6 comprises apair' of'fi'ngers' 24 slidably mounted'in base 25 and actuated by a'linkage' indicated at'26; Each of" the heads '21 is providedwith a suitably aifixed'projecting' member 27' en'gageable by'itsrespective' finger'24 at'on'e'. of the head positioning, stations D and E, to stop the rotation of' the heads 21'. After the rotation of the heads-21 has been" arrested; movable-track orguide'mem' bus 28 and 29' also slid'ably mounted in base 25 are moved inwardly toward the' center of the turret 20 by a cam actuated mechanism" indicated at 31, each" engaging afiat 300m thehead 21at=itsrespectivestation: Guides 28" and 29 serve to maintain orientation of the heads23 for'theremainder of the: dwell anddurin'g partof the in engagement with a'fixed' track 32 which exten'dsto' subsequent stationswhere'it is necessary tomaintainorientation o'fih'eads 21;

We-will'now proceedwitha more detaileddescription of the fingers 2'4" and their associated actuatin'gjlinkage' 26 which movesthe fingers 24 into andout of engagement with the members 27' of the" heads 21. during a dwellperiod of the turret'20. Thefingers24are linked together at their outer ends, away from'the turret'20', by

a cross-bar 33, seen in Figure 4, having a cylindrical center section 34enga'gedby a slot35 in the upperen'dof with an actuatingcam 43 mounted on :rshaft 44; whichmakes; one completes revolution during each indexing;

cycle of the turret 20. A link rod 45 pivotally connected. tetheouterend of the lever 39 and the inner end of the arm 38 transmits the motion of the lever 39 to the arm 38. A tension spring 46 fastened to the inner end of the arm 38 and suitably anchored to the base urges the follower 42 into contact with the cam 43.

The movable guides 28 and 29 and their actuating mechanism" 31, which wehave provided for maintaining orientation. of. the heads 21 at stations D and E after the fingers 2 4-have' Eeenwithdrawnafrom their head stopping position, will now be described with: particular reference to Figures 2-4. The guides 28 and 29 are slidably mountedin'b'ase ZS and'each is movab'lebetween'an inward position abuttinga' flat one-head 21 and an outwardly retracted position out of contact with any part of the head 21. A cross bar 50 having a cylindrical center section 51 is fast on the outward end of the guide 282 On the other hand between the guide 29' and the bar 50 there is a lost motion mechanism comprising a stud 52Tfij ed"to'-theouter end" of the guide 29 and free-to move in a-hole 53 in thebar'50; a-spring 54 compressed between th'e guide 29 and'thebar 5'0-and' urging the guide 2'9 ii1war'dl'y into" contact with the'fiat30' of the head 21' atstation E; and a'pa'ir of'checlenuts 55 which adjustably limit thespac'ing Between the bar 50and the guide 29 Motion is supplied to the guides 28 and 29 by a mechanism' comprising a" bell" crank indicated at 56 (Fig; 4) having a vertical arm 57 provided at itsup'per end Witha slot 5'8 which engages the" cylindrical section 51' of the cross hat- 50'. The Bell crank 56is' pivoted on a shaft 59 andinclu'ds agenerall'yhorizontal armfifl wig. 2) which isicoupled to anactuating' linlage comprising alever'61 pivotally mounted on thesh'a-ft 40 and carrying at its inner end a: foll'ower'roll 62" in contact with a cam63' which is fiked to-theaforementioned' shaft 44. A link rod 64- pivotally' connected to the-outer end of' the lever 61 and' the inner end of the'arm Gil-transmits themotion of-the' lever 61 to the bell cranl'56: A spring 65 con nected to the arm at one end and anchored'tothebase 2'5 at= the otherurges' the follower roll 62 into contact Withthe cam 63.

Although our apparatus'is" adapted to being" employed in conjunction with s'ealing" machines driven at a wide rangeofspeeds,- it-"is believed-that'its operation will'lbest' be appreciated from an" example in which specific rates aregiven'for purposesof-illustration only; Thus itisto be assumed that the turret 20 is'indexed 1500 tim'es per hour or once each 234 seconds'and that motion and dweIl periods are .8 and" 116*second's respectively. It'may also be assumed forpurposes of this illustration'that the heads hypothetical case under" consideration .6" second is required at "the latter" part ofthe dwell period of the'"turret 20 for"the operation'ofour apparatus and the heads 21' are allowed to rotate duringthefirst'full secondof the" with .6 secondofl the dwell rem'aining.

required to arrest the rotation of the heads 21 each contacts the flat 30 on its respective head during the .2 second remaining before the start of the index motion of the turret 20. After the flats 30 have been engaged by the guides 28 and 29, the fingers 24 are withdrawn out of engagement with the members 27.

It will be found convenient for purposes of clarity in describing the action of the guides 28 and 29 during the index motion of the turret to designate the heads shown in Figures 1 and 3 at stations E, D, and C as the first, second and third head respectively. Shortly after the turret 20 starts to move the flat 30 on the first head 21 slides into contact with the fixed track 32. The second head 21 is then moving into engagement with the guide 29 as the third head 21 approaches the guide 28. The relative lengths and positions of the guides 28 and 29 is such that the second head is retained against rotation by the guide 29 before the third head can contact the guide 28. At this point, the bell crank 56 is revolved part way in a clockwise direction (Fig. 2) withdrawing the guide 28 which is fixed to the cross-bar 50 and thereby allowing the third head to continue rotating. The guide 29, however, remains in contact with the flat 30 on the second head, under the inwardly directed force of the spring 54. As the index motion of the turret 20 continues, the flat 30 on the second head moves into contact with the track 32 before the third head which is still rotating can touch the guide 29. After the second head is secured against rotation by sutficient engagement of its flat 30 with the fixed track 32, the bell-crank 56 is pivoted further in a clock- Wise direction. In its resultant outward motion, cross bar 50 contacts the check nuts 55 on the stud 52, thereby forcing the guide 29 outwardly away from its head orienting position and permitting the third head 21 to continue rotating as it arrives at station E. It will be understood that in the same motion of the turret which carried the third head 21 from station C to station E, the adjacent head 21 occupying station B (Fig. l) at the commencement of the indexing cycle is moved to station D. With the fingers 24 and the guides 28 and 29 retracted, the heads 21 at stations D and E continue to rotate until our apparatus is again actuated to repeat its head positioning operation.

From the foregoing description of a preferred embodiment, of our invention, various modifications within the scope and spirit of our invention will be apparent to those skilled in the art. For example, the guides 28 and 29 may be actuated by separate mechanisms. On the other hand, some aspects of our invention can be used with a single index machine if desired. It is therefore not intended that the invention be limited to the particular arrangement of parts illustrated and described but rather to rely upon the definitions of the invention provided by the appended claims.

What we claim is:

1. In a lamp sealing machine having a turret and a plurality of rotatively driven heads mounted at regular intervals on said turret, said heads being moved intermittently by said turret to a plurality of stations, apparatus at one of said stations for angularly orienting each said head, said apparatus comprising releasable means for arresting the rotation of the said head in a pre-determined orientation; movable guide means for engaging said positioned head to prevent further rotation; a fixed track thereafter engageable by the said oriented head whereby said orientation is maintained as the said head is moved by said turret to subsequent stations; and means for moving the said arresting means and the said guide means in required time sequence.

2. Apparatus for angularly orienting rotatable heads mounted on an intermittently movable turret and carried thereby to a plurality of stations, said apparatus comprising: a projecting member on each said head; a finger at one of said stations, said finger being slidable between an inward and a retracted position and engageable in its inward position by the said member to arrest the rotation of the same in a predetermined orientation; means for thereafter maintaining the said arrested head in said predetermined orientation during the motion of said turret including a substantially flattened surface on each head, said surface having a fixed position relative to the said projecting member, a guide also movable between an inward and a retracted position and engageable in its inward position by the said surface; a fixed track also engageable by the said surface during the motion of said turret; and means for actuating the said slide and the said guide in predetermined time relation.

3. Apparatus for angularly orienting two adjacent rotatively driven heads on a sealing machine turret provided with a double index motion, said apparatus comprising means for arresting the rotation of said heads in predetermined positions at a first and second station; means for retaining each said positioned head against further rotation including a movable guide at each said station, a fixed track at subsequent stations and a generally flattened surface on each head engageable by said guide and said track; and means for actuating said arresting means and said guide in required time sequence.

4. Apparatus for angularly orienting two adjacent rotatively driven heads on a sealing machine turret provided with a double index motion, said apparatus comprising means for arresting the rotation of said heads in predetermined positions at a first and second station; means for retaining each said positioned head against further rotation including a movable track section at each said station, a fixed track at subsequent stations, and a flat surface on each head engageable by said tracks; means for moving said track sections into and out of engagement with said flat surfaces including a lost motion mechanism whereby the track section at said first station is withdrawn to permit continuing rotation of a head arriving at the positioning station while the track section at the second said station maintains engagement with a head moving toward subsequent stations; and means for actuating said arresting means and said moving means in required time sequence.

References Cited in the file of this patent UNITED STATES PATENTS 2,109,505 Rue et al. Mar. 1, 1938 2,630,204 Lichtenberg Mar. 3, 1953

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