US2860760A - Lamp bulb loader - Google Patents

Description

E. E. YEo x-:T AL

Nov. 18, 1.958

LAMP BULB LOADER e sheetssheet 1 Filed June' 17, 1955 HENRY B MALNE Y ATTORNEY.

Nov. 18, 1958 Filed June 17, 1955 fr# @E 35 f35 n3 Fff- 5 E. E. YEO ET AL LAMP BULB LOADER 6 Sheets-Sheet 2 INVENTUM: EFA/57' E. YEO HE/VKY B.MALONY ATTORNEY.

Nov. 18, 1958 Filed June 17, 1955 E. E. YEo E1' AL 2,860,760

LAMP BULB LOADER 6 Sheets-Sheet 3 INVENTOR. MNEST E. YEO HENKY B. MALO/VE'Y BYMw-ww MM,

ATTORNEY' Nov. 18, 1958 E. E. YEo ETAL 2,860,760

LAMP BULB v'LOADER Filed June 17, 1955 6 Sheets-Sheet 4 gam a4 40 73 4o I 44 Q 4l 44 g as INVENTUM: srlvzsr Yeo MEN/:Y a. MALONEY diam/L4M Nov. 18, 1958 E, E. YEo ETAL LAMP BULB LOADER 6 Sheets-Sheet 5 Filed June 17, 1955 INVENTUM. ENET E: YED IVE/Vif Y B. MAL/VE Y W ,3A/Lm,

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Nov. 18, 1958 E. E. YEo ETAL LAMP BULB LOADER 6 Sheets-Sheet 6 Filed June 17, 1955 l/OV AC.

INVENTORS: ERNEST E. Yfo HENRY B. MALa/vEY United States atent LAMP BULB LOADER Ernest E. Yeo, Wenham, and Henry B. Maloney, Wakefield, Mass., assignors to Sylvania Electric Products Inc., Salem, Mass., a corporation of Massachusetts Application June 17, 1955, Serial No. 516,212 7 Claims. (ci. 19e- 24) `specifically concerned with such apparatus adapted for higher speed than that of bulb transfer mechanisms heretofore employed, although it is not limited to such use.

Inthe manufacture of incandescent lamps, one of the steps involved is that of sealing a glass envelope or bulb `over the so-called mount, which ordinarily includes a glass stern with lead-in wires and exhaust tube sealed therethrough. This operation is performed on a sealing l machine which is provided with a plurality of sealing heads each comprising a hollow sealing pin for receiving the amount and a bulb seat adapted to support and position the glass envelope in encompassing relationship over the mount. As it is delivered to the sealing pin, the amount comprises a stern tube having a flared portion resting upon the upper end of the sealing pin and an upper atportion sealed about lead-in wires, an exhaust tube extending downwardly into the sealing pin,

and a filament held under tension between the upper ends of the lead-in wires. The lower ends of the lead-in Wires also extend linto the sealing pin adjacent to the exhaust tube. With the mount in this position, the `bulb which generally has an enlarged rounded portion and a depending neck portion is then loaded over the mount with its neck encompassing the flared portion of the stern tube. It is to be noted that the extended nature of the filament leaves little clearance between its ends and the neck portion of the bulb as the latter is being loaded over the mount. It must also be appreciated that the filament is `a fragile article which may be destroyed if a bulb collides with it while being loaded. To avoid such collisions it is necessary that the neck follow an unobstructed path with a certain `degree of accuracy.

Heretofore bulbs have generally been loaded manually onto the spindles of sealing machines that operate at relatively low speeds. Attempts have been madeto load mechanically, but hitherto mechanical loading has not been entirely successful, particularly at high speeds. One form of loader has consisted of a rotating turret having a plurality of bulb supporting members and means for indexing the supporting members successively to a transfer station. The bulbs are then loaded into the sealing spindles by a transfer plunger having a vacuum chuck at its lower end adapted to engage the bulbs. `In

accomplishing this transfer in such conventional machines the plunger first moves downwardly to engage the bulb. Thereafter it moves upwardly to permit the neck of the bulb to clear the bulb support on the turret; sidewardly to position the bulb in registration with the spindle to be loaded; and finally downwardly to load the bulb into its seat.

During these motions the bulb is only retained by suction or vacuum in the chuck. Thus although it is y 2,860,760 Patented Nov. 18, 1958 ice readily possible to alignthe neck' of the bulb whileit is resting in the turret, such alignment maythereafter be disturbed by forces acting upon the bulb during subsequent transfer motions. b f

Another conventional bulb transfer mechanism` has employed a similar turret and plunger, `but instead of `lifting the bulb and moving it clear of the turret the must meet it without impact and preferably with great b accuracy in order to avoid breakage. Secondly, `the preliminary upward motio-n of the bulb takes time and increases the risk of the bulb slipping slightly out of position on the chuck. Thirdly, the required extra motions of the mechanism takes time as well as extrav care in co-ordination, and fourthly, the sideways motion of the plunger in the first described machine tends to dislocate the bulbs. These disadvantages are greatly increased when the operating speed of these machines is increased.

Therefore it is an object of our `inventionto provide mechanism for transferring bulbs which will at one and the same time accomplish the transfer accurately and at high speed. More specifically it is an object to provide a bulb transfer in which the motions `of the apparatus do not increase the chance of inaccuracy when the transfer rate is increased. j

An additional object of our invention isto provide such an apparatus with means for transferring bulbs un- Figure 2a is a fragmentary v1ew 1n cross-section of V the upper portion of the bulb transfer plunger;

` Figure 3 `is a View in side elevation showing ourapparatus together with `a spindle on the sealing `machine positioned to receive a bulb;

Figure 4 is a view inV front elevation of our apparatus and a portion of the adjacent` sealingturret; l'

Figures 5 and 6 are fragmentary end and side views respectively of `a turret index actuating mechanism;r

Figures 7 and V8 are fragmentary end and side views respectively of a transfer plunger operating mechanism;

Figure 9 is a View `in side elevation of amount `detecting device; and t Figure l0 is a schematic diagram of lockout mechanism cooperatively associated with the mount detector. As seen in Figure l, our apparatus is disposed adjacent to a portion of a sealing machine turret indicated at 25 having a plurality ofsealing` heads or spindles indicated at 27 mounted along its periphery. Turret 25 in this particular arrangement is double indexed or moved intermittently a distance equal to the space between alternate heads 27 on the turret. The stations `occupied `by heads 27 shown have been designated. for convenience `of reference in Figure l by the letters A through H. Thus a head 27 on the turret 25 is indexed successively to stations A, C, E, etc. while the other of a pair of adjacent heads 27 is moved to stations B, D, F, etc. Only a fragment of the turret 25 is shown `but it `will be understood that provision is made for supplying a mount t0 3 each head prior to reaching stations A or B. Our apparatus simultaneously loads a bulb 28 into bulb seats 24 Qof heads 27 at stations C and F during a dwell 1n the motion o'f turret 25.

AsA shown in Figures l-4, the 'general' arrangement "of our apparatus includes apair of turrets lndlcated generally fat which are indexed to transport bulbs 28 from the'inclined'rails 21 to a transfer station in vertical Vregistration with spindles to be loadedat stations C and P of sealingrriachine turret 25. Bulbs 28 are carried bythe turrets 20 Ion spring-loaded fingers 23 arranged in groupsof three and adapted to support the weight of VAthe bulb. These ngers yield under a load somewhat greaterthan the weight of the bulb to permit the bulb 2-81topass downwardly to the sealing machine. At each of the Vsaid transfer stations a loading plunger indicated at22 y-having a vacuum or suction cup indicated at '29 at its lower 'end engages the bulb 28 and in oney motlon urges 'the bulb 28 through the lingers 23 in turret 2@ 'and `deposits it into a bulb seat 24 of a head 27.

Prior to engagement of the bulb 28 by a suction cup at are placed at stations A and D, one station in advance of each bulb loading station. If a head 27 at station A, for example, does not carry a mount 30, the

mount detecting device 25 cooperates with mechanisms which will be described later to prevent indexing of right hand turret 20 (Fig. 1) and actuation of its associated plunger 22 when the vacant head` arrives at station C.

The turrets 2t) and their indexing mechanisms will now be described in detail with particular reference to Figures l, 3 and 4. Each turret supports a plurality of bulbs around its periphery with the bulbs 28 resting on cradles formed by spring-loaded fingers 23 arranged in groups of three. The fingers 23 project inwardly below appropriate openings in the outer edge of the turret.

The turrets 20 are rotatably mounted in suitable support elements and each is provided with an independent indexing mechanism. Generally this mechanism consists in a rachet wheel 31 secured to the under-side of each turret 2t) (Fig. 3), a spring-loaded pawl 32 and a pivotally mounted yoke 33 upon which the pawl 32 is carried. The yoke 33 is actuated by a vertical tie rod 34 operating through a pivotally mounted bell-crank 35 and rod 36.

The part of our mechanism which produces reciprocating motion of rod 34 is shown 'in Figures 5 and 6 and consists of a pivotally mounted rocker arm 36 having a follower roll 37 in contact with an actuating cam 3S mounted on a shaft 39 rotated in geared relation with the sealing machine. A spring 46 maintains follower 37 in contact with cam 38. Shaft 39 makes one revolution for each indexing cycle of the sealing` machine.

Since it is undesirable to feed a bulb to a sealing head 27 not carrying a mount, our apparatus is provided wlth a lockout mechanism adapted to prevent the index- .ing ofthe turrets 20 whenever a head 27 will arrive at the transfer station without a mount in it. A stud indicated at 83 is secured to the rocker arm 36 near its outer end and "engages a pair of drive members 40 one being attached tothe lower end of each rod 34. Each l' drive member 40 has an elongated vertical slot 45 enlarged at its lower end where it engages an enlarged 4 portion 41 of stud 83 during cycles when turret 20 is to be indexed. Compression springs 42 urge members 4t! inwardly and maintain the engagement between memb'ers 40 andstud 83 at such times. When the turret 20 is not to be indexed, a solenoid 43 is actuated as will be explained below, and forces a member 40 outwardly,

operatively disengaging it from the stud 83. At such times the stud is maintained in position relative to the drive member 40 by means of a guide 44 on the end of stud 83. The guide 44 has a sufficiently small diameter to ride freely in the said elongated slot 45 so that at such times the related rod 34 is not actuated.

l We will now proceed with a description of the plungers 22 and their associated actuating mechanisms. Since both plungers 22 are identical only one will be described with particular reference to Figures Y2 and 2a. Plunger 22 is slidably mounted in a housing 47 fast on a bracket 48. In turn, bracket 48 is fast on vertical shaft 61 (Fig. l) which is reciprocated vertically to accomplish the transfer of bulbs 23 from turret 20 to seats 24. The weight of plunger 22, which is tubular in form, having an internal passage 57 is supported by a flanged head 49 resting upon the upper surface of housing 47. A cap 5tlcarrying an internallymounted `O-ring 51 is disposed over the upper end of plunger 22. A stud 53 upon which cap 47 is suspended is provided :with a check nut 52, generally adjusted to permit cap 50 to move upwardly a short distance. Near its lower end housing 47 is provided with an internal port 55 in communication with a source of vacuum or suction (not shown) through ilexible hose 54. A cam operated valve (not shown) is disposed in this line to turn the suction on and off when required as will be explained below. The passage i 57 in plunger 22 communicates with an external annular groove 56 through an aperture 58. A vacuum chuck or suction cup indicated at 29 is mounted at the lower end of plunger and is adapted to contact bulbs 28 and support them during the transfer operation. A spring 59 supports suction cup 29 which is permitted a slight swivel to adapt to varying bulb contours. Internally chuck 29 carries 'a resilient O-ringv60 adaptedto seal itself under suction against a bulb 28.

The plunger 22 accomplishes the transfer of a bulb 28 from the turret 20 into a seat 24 in one continuous downward motion. As chuck 29 approaches the upper surface of the bulb 28, the cam operated valve is actuated thereby connecting port 55 to the vacuum source. After chuck 29 has engaged the bulb 28 plunger 22 is forced upwardly in housing 47 until head 49 contacts O-ring 5l and groove 56 is in registration with port 55. Since head 49 then becomes sealed against O-ring 51 and a bulb 28 closes olf the chuck 29 by contacting O-ring 60 plunger 22 will remain in this position until the suction is turned otf. Thus the plunger 22 continues its descent until the bulb 28 approaches the seat 24. At this point the suction is turned otlf by the cam operated valve thereby releasing the bulb 28 and permitting plunger 22 to drop to its initial position in housing 47. To facilitate retention of plunger 22 by vacuum against ring 51, it has been found advantageous to fabricate the plunger 22 of a light weight metal such as aluminum, for example.

Housing 47 is aixed to bracket 48 which is in turn mounted on vertical shaft 61 (Fig. 3). At its opposite end bracket 48 supports a second plunger assembly indicated 'at 62 whose function is retaining a bulb in turret Zti while it is being internally monogrammed. Assembly 62 consists of an outer sleeve 63, fixed to a bracket 48, in which plunger 65 is journalled and lightly springloaded. At its lower end plunger 65 is provided with a suitable cup member 64 which engages the bulb as plunger 22 completes its loading motion and before bulb 2S is contacted internally by a monograrnming stamp.

The part of our mechanism which reciprocates shaft 6l to effect vertical movement of plungers 22 and 62 will now be described in greater detail with particular reference to Figures 3, 7 and 8. Each shaft 61 is mounted in bearing members inside its respective turret 20, additionally journalled in an appropriate base supporting element 66 and suitably keyed to prevent rotation. Reciprocation of shafts 61 is accomplished by a mechanism located belowl support 66 and shown in Figures 7 and 8. Vertical supports 66 are tied together at their upper end by a cross member 67 in which the lower ends of shafts 61 are guided. A yoke 68, guided on slide rods 69 and 70 is reciprocated vertically by'tierod 71 whose upper end is pivotally connected to yoke 68. Slide rods 69 and 71 are supported in parallel relationship in any appropriate manner as for example, between cross member 67 and a similar member not shown at the lower end.

A lock out mechanism is provided to prevent the downward motion of either shaft 61 when it is not desired to `feed a bulb to a particular head 27 which does not contain a mount. When a shaft 61 is to be moved downwardly its weight is borne by yoke 68 and shaft 61 descends with the yoke 68. However when no mount hasbeen detected by mount detector 25 (Fig. l) appropriate solenoid 72 is energized as will be explained later. Upon being energized solenoid 72 projects its armature 73 into a slot 75 in the outer end of yoke 68 before the yoke starts its downward travel. At such times the lower end of shaft 61 cornes to rest upon armature 73 and does not travel downwardly with yoke 68. When solenoid 72 remains de-energized, its armature 73 remains retracted out of the path of shaft 61 by the tension of spring 74.

The reciprocating motion of tie-rod 71 is produced by mechanisms shown in Figure 8 comprising a rocker arm 76 pivoted on shaft 77 and having a follower roll 78 in contact with cam 79. Rotation of cam 79 is provided by the `cam shaft 39 previously referred to in connection with the turret index actuating mechanism illustrated in Figure 6. A link rod 80 connects rocker larm 76 to one l end of a lever 81 pivoted on shaft 82, thereby translating the motion furnished by cam 79 into repicrocation of tie rod 71 pivotally connected to the other end of lever 81. We Will now describe more particularly our mount detecting device 25 shown at Figure 1. Mount detector 25 may be seen in greater detail in Figure 9 and its associated electrical circuiting is shown diagrammatically in Figure l0. At station A components of mount detector including anfair nozzle 85 and a switch 86 are xedly positioned.l Nozzle 85 is suitably supported outside the path of heads 27 on turret 25 and switch 86 is mounted on any lixed supporting member not shown. Associated plumbing not shown, including solenoid operated valve 87 shown schematically in Figure l0 provides communica- "tion between nozzle 85 and a source of air under pressure.

Switch 86 has an actuating arm 91 provided with a buttery 88 at its upper end. With no mount in head 27 a blast of air from nozzle 85 is aimed directly at buttery 88 which is thereby moved rearwardly to a position shown in dot and dash thereby closing switch 86 which is normally open. However, with a mount present in head 27 the air stream is deflected and butterfly 88 remains unmoved.

The operation of our mount detector 25 and its cooperative relationship with lock out solenoids 43 and 72 will now be explained with reference to Figure l0. It is believed that it will be helpful to note at the outset that the entire operation to be described takes place during a period of time commencing just prior to the indexing of sealing machine turret 25 and ending prior to the next indexing motion. Cam actuated switch 90 is first closed by the action of cam 102 thereby energizing valve operating solenoid 87 and causing an air blast from nozzle 85. Assuming that no mount is present in head 27, buttery 88 will be moved, closing switch 86. When switch 86 is closed, relay solenoids 92 and 93 will be connected across the source of supply current and thereby energized. Solenoid 92 closes normally open switch 94 providing for current ilow through solenoids 92 and 93 as long as no-rmally closed switch 101 which is in the series circuit remains closed. At this point cam operated switch 90 is allowed to open cutting off current to valve operating solenoid 87 and terminating the air blast-from nozzle 85. When the air is shut o switch 86 again assumes its normally open position but closed switch 94 acts as a memory device while turret 25 is indexed bringing the head 27, in which no mount is present, to the bulb-loading station.

During the indexing of turret 25 shaft 61 is moving upwardly (Fig. 3). The timing of our apparatus is such that as soon as plunger 22 clears turret 20 the indexing motion of turret 20 should normally occur by the operation of mechanisms which have already been described. However, if a mount vacancy has been detected in head 27 switch 94 is closed, relay solenoid 93 remains energized and switches 95 and 96 which it operates are also closed. lust prior to the start of the upward motion of rocker arm 36 (Fig. 6) switch 97 is closed by the operation of cam 103 and solenoid 43 is energized disengaging drive member 40 from stud 83. At the end of the indexing motion of turret 20 plunger 22 normally descends to engage bulb 28. However, with switch 96 closed as a result of the absence of a mount in head 27, solenoid 72 is actuated just prior to the start of the descending motion of yoke 68 (Fig. 7). When this happens shaft 61 remains suspended on armature 73 and there is no resulting motion of shaft 61. Finally, before another mount detecting blast from nozzle 85, switch 99 is closed momentarily by cam 105, energizing relay solenoid 100 with which it is in series. Solenoid 100 opens normally closed switch 101, de-energizing solenoid 92, thus allowing switches 94, 95 and 96 to return to their normally open position for the next mount detection operation.

Although mount detector 25 and its associated circuit has been described as shown at turret station A in Fig. l, it will be understood that a similar device is located at station D. Thus mount detectors 25 at stations A and D inspect heads 27 for mount vacancies before the heads are moved to bulb-loading stations C and F respectively. In the event that a mount vacancy is revealed appropriate solenoids 43 and 72 are energized to lock-out motion of the particular tie rod 34 and shaft 61 concerned.

We will now describe in detail a bulb alignment mechanism 26, shown in Figures 1 and 3, which positions the neck of the bulbs 28 at the transfer stations before the said bulbs are engaged by their respective plungers 22. At each loading station we employ a pair of centralizing arms pivotally mounted on base plate 111 and actuated in geared relationship by a linkage comprising a link rod 117 reciprocated by a bell-crank 112 to which it is pivotally connected and tie rod 113 which is in turn reciprocated vertically (Fig. 3) by a standard cam, rocker arm, and follower arrangement now shown. Link rod 117 is pivoted to one end of a crank arm `114 fast on a rotatably mounted shaft and a lever 116 is also affixed to the shaft 115. A rod 118 links each end of lever 116 to a crank arm 119 fast upon a short shaft 120 on which one arm 110 of each pair is also xedly mounted. Shaft 120 is rotatably mounted in plate 111 and the two arms 110 of each pair move in unison in geared relation.

Just before plungers 22 engage bulbs 28 at the two loading stations rod 113 moves downward (Fig. 3) thereby effecting a closing of each pair of arms 110 about the neck of the bulb 28. This centralizing engagement is maintained briefly as the bulb 28 is engaged by plunger 22 and starts to move through turret 20. Then rod 113 moves upwardly, returning arms 110 to their open position permitting bulb 28 to pass down through.

Having thus disclosed and described a preferred embodirnent of our invention, several minor variations corning within its scope will now be apparent to those of ordinary skill in the art. It is therefore not intended that our invention be limited to the particular arrangement and combination of parts disclosed but rather to depend upon the limitations imposed by the appended claims.

What we. claim is;

1.,Apparatus for transferring bulbs comprising spring loaded lingers for receiving and bearing the weight of said bulb, means for positioning said bulb vertically on said fingers and while it rests thereon, a plunger for lurging said bulb downwardly against the spring'force of said fingers, and means for retaining said bulb from dropping after said bulb has passed clear below said fingers including suction means operatively associated with said plunger.

2. Apparatus for loading bulbs into seats o l spindles comprising spring loaded fingers defining cradle for holding a bulb, means for moving said cradle to a loading station in alignment with a seat, a plunger, means for moving said plunger to urge said bulb through said cradle against the spring forcee of `said fingers, suction means on s aid plunger for retaining said bulb on said plunger after saidfbulb has been pushed through said cradle, and means including a valve for thereafter interrupting said suction and releasing said bulb from said plunger to effect a deposit of said bulb into said seat. 3. Apparatus for loading bulbs into seats of sealing spindles comprising spring loaded fingers defining a cradle for holding a bulb, means for moving said cradle to a loading station in alignment with a seat, means for positioning said bulb accurately in ysaid cradle when at said loading station including a pair of arms and means for moving said arms into and out of contact with said bulb, a plunger, means for moving said plunger to urge said bulb through said cradle against the spring force of said fingers when said arms are out of contact with said bulb, suction means on said plunger for retaining said bulb on said plunger after said bulb has been pushed through said cradle, and means including a valve for thereafter interrupting said suction and releasing said bulb from said plunger to effect a deposit of said bulb into said seat.

4. Apparatus for transferring bulbs to seats of sealing spindles comprising a turret; a plurality of bulb cradles on said turret each including fingers spring loaded to support the weight of said bulb but displaceable under greater load to allow passage of said bulb through ysaid cradle; means for moving said cradles succesively to a transfer station; suction means for engaging said bulb at said station; means for urging said bulb through said cradle and transporting same toy one of s aid seats; and valve means operatively associated with said suction means to effect said suction engagement and its subsequent release thereby depositing said bulb into one of saidl seats.

v. Apparatus for transferring bulbs to seats of sealing spindles comprising a turret; a plurality of bulb radles on said turret each including lingers spring loaded to support the weight of said bulb but displaceable` under greater load to allow passage of said bulb through said cradle; means for moving said cradles successivelyf to a Galibier transfer station; suction means for engaging said bulb .at said station; means for positioning Said bulbs in ac,- curate vertical alignment including apair of pivotally mounted positioning arms adapted to grip the lewer portion of said bulb, and means for urging said arms into contact with said bulb; means for releasing said positioning arms; means for thereafter urging said bulb through said cradle and transporting same lto one of said seats; and valve means operatively associated with said suction means to effect said suction engagement and its subsequent release thereby depositing said bulb into one of said seats.

6. Apparatus for transferring bulbs to seats of sealing spindles comprising: a plurality of bulb cradles, resilient means on each said cradle for supporting the weight of a bulb and adapted to yield under load greater than said weight to allow passage of sjaid bulb through said cradle; means for positioning said cradles successively at a loading station; plunger means for urging a bulb at said station against said resilient means through said cradle and downwardly to one of said seats; vacuum chuck means carried by said plunger means for engaging and retaining said bulb during its movement towardI said seat, a source of vacuum, means for supplying said vacuum to said chuck and for controlling the same including a first valve, means for opening said first valve and supplying vacuum to said chuck in response to the pressure of said chuck against said bulb as said plunger is lowered, and external valve means for cutting off said vacuum after said plunger has transferred said bulb downwardly to said seat.

7. Apparatus for transferring bulbs to seats of sealing :spindles comprising: a substantially khorizontal turret; a plurality of bulb cradles on said turret each comprising resilient support membersbearing the Weight of said bulb but displaceable under a load greater than said weight to allow passage of said bulb `through said cradle; means for indexing said cradles successively to a loading station; means for urging a bulb at said station downwardly through said cradle into one of said seats including a vertically reciprocable plunger and a vacuum chuck mounted on said plunger for engaging said bulb; lost motion valve means for supplying vacuum to said chuck when said chuck engages said bulb; and exterior valve means for cutting off the vacuum to said chuck after the completion ofthe downward motion of said plunger thereby effecting a deposit of said bulb in said seat.

References Cited in the tile of this patent UNlTED STATES PATENTS Danziger July 19, 1949

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