US2923050A - Lamp basing machinery - Google Patents

Description

Feb. 2, 1960 D. J. DWINELL' ET AL 2 LAMP BASING MACHINERY Filed Feb. 10, 1958 5 Sheets-Sheet 2 INVENTORS DWWWTADWWWML -aawumlueluorr BY IHTHARW a A4xamer FRwMKiM0nuHr Feb. 2, 1960 D. J. DWINELL ET AL LAMP BASING MACHINERY 5 Sheets-Sheet 4 Filed Feb. 10, 1958 INVENTORS DWIGHT J. DWI/(ELL GL'OKGE A. [LL/0T7 Feb. 2, 1960 A D. J. DWINE LL ETAL LAMP BASING MACHINERY Filed Feb. 10, 195B 5 Sheets-Sheet 5 United States LAMP BASING MACHINERY Application February 10, 1958, Serial No. 714,327

8 Claims. (Cl. 29-25.19)

This invention relates in general to the manufacture of lamps. More particularly, the invention relates to the operations of preparing lamp leads for basing, the threading of the leads through bases, and the actual basing of the lamps.

High speed lamp manufacture requires that processing operations be mechanized wherever possible. In the particular case of elongated tubular lamps of which fluorescent lamps are typical, a major step forward has been made by the relatively recent development of horizontal machinery on which the processing operations are carried out while the lamps are in a horizontal position.

The horizontal machinery consists usually of a conveyor which moves the lamps along a predetermined path. Disposed at both sides of the conveyor are similar devices for performing certain manufacturing operations on the lamps during their travel along the aforesaid path. After such operations as lamp sealing, evacuation, gas fill and tipping off are performed by suitable automatic devices, bases must be placed on the lamps. Electrical contacting pins on the bases must be connected in suitable conducting relationship to lead wires of the lamps, and the bases themselves must be firmly attached mechanically to the glass ends of the lamps. The usual practice is to solder or weld the lamp leads to the base contacts or pins and to cement the bases to the glass of the lamp by a tenaciously adherent cement, such as a Bakelite cement which may be heat cured to assure the permanent adherence of the bases to the lamps.

There are some lamps, for example, the so-called instant-start types which have single contact bases. That is, each base is provided with only one conducting mem her for contacting a single contact receptacle at each end of the socket in which the lamp is used. The conducting member of the base is usually a centrally located, roundended, metallic thimble which projects outwardly from an annular member made of Bakelite or other insulating material. The annular member is dished to accommodate a ring of basing cement and to fit over the end of the lamp to which it is cemented. The metallic thimble has an opening formed in its extreme end to receive leads from the lamp.

Because the lamps are provided with oxide coated filamentary electrodes through which current must be passed during manufacture, two leads are necessarily present at each end of the lamp. It is desirable for several reasons that both these leads be electrically connected to the single contact of the base. These leads are usually of the order of .020" diameter each and the opening in the base contact runs about .059 to .060 diameter. Obviously, there is sufficient clearance to pass the leads through the opening, but the fit is relatively close. The fit must be maintained relatively close or the subsequent soldering operation will not join the leads and the base member in good electrical contact.

First attempts at threading the two leads through a base contact were purely manual. The operator merely drew the leads out straight and parallel to each other Patented Feb. 2, 1960 lamp end. A slight twisting motion applied to the base aided the manual threading operation. Subsequently, a conically tapered base contact was used in an early automatic threader. The conical internal surface facilitated threading, but the conical external surface failed to make good contact in the receptacle of the socket designed to hold it. A mechanical threading device which merely drew the leads out straight and held them in that posidon while a base was forced over them was also tried. This device was unsatisfactory in numerous respects, but primarily because jamming of the leads rather than the desiredthreading too often occurred.

It is, therefore, an object of the present invention to provide automatic, trouble-free threading of lamp leads and basing of lamps.

it is a further object to avoid the jamming of leads encountered in using previously known equipment.

A still further object is to further mechanize the manufacture of discharge devices such as fluorescent lamps.

Another object is to reduce the cost of lamps by mechanization of process steps and elimination of waste and duplication of effort in lead-threading and basing of lamps.

In general, the present invention is organized about a conveyor along which lamps are indexed. At each dwell position of the lamps, one or more of various processing operations take place. For purposes of description of the present invention it may be assumed that such process steps as evacuation, gas-filling and tipping have been completed as have certain electrical operations and checks on the lamp. Two leads extend from each end of the lamp and may be oriented in any random position, when the lamps reach the point on the conveyor at which the present invention comes into play.

At a dwell position of the lamp, a rotating head advances toward each end of the lamp. Each of the rotating heads includes a pair of jaws which are sprung wide apart as the head advances toward the lamp end. The head stops its advance adjacent the lamp, but rotation continues. When, however, retraction of the head occurs, the jaws close tightly. As the rotary retractive movement begins, the wires are seized by the jaws and are then given a long helical twist as retraction continues. The jaws remain closed even after they are re tracted to a point beyond the full length of the leads and do not reopen until a new cycle of operation begins.

The lamp is then indexed forward to a new dwell position, adjacent base-threading heads. Guide structures which may be in the form of gravity feed slides are dis, posed at'each end of the lamp and carry bases which have previously been filled with basing cement. The cases are released one by one to vacuum chucks adjacent the ends of the lamp. Each of the vacuum chucks consists of a hollow rammer shaft which rotates and which may be advanced and retracted relative to the lamp end. The base carried by the hollow shaft is rotated and advanced toward the lead wires of the lamp which were provided with a helical twist at the previous dwell position. The base has a central contact pin in which an opening is formed. The base is rotated during its travel toward the lamp end, the rotation aiding the lead wires to enter and pass through the relatively small hole at the end of the base pin. As the base approaches the glass end of the lamp, rotation of the hollow shaft is discontinned by the disengagement of a clutch. Finally, as

received by the vacuum chuck at the end of the hollow shaft to repeat the threading cycle.

For a better understanding of the present invention together with other and further objects, features and advantages, reference should be made to the following description of a preferred embodiment thereof which should be read in connection with the accompanying drawings in which:

Fig. 1 is a plan view of an embodiment of the present invention;

Fig. 2 is a side elevation partly in section of the wire twisting portion of the present invention;

Fig. 3 is a side elevation partly in section of the basethreading portion of the present invention;

Fig. 4 is an enlarged side elevation, partly in section, of working elements of the mechanism shown in Fig. 3;

Fig. 4a is a detailed sectional view of the vacuum breaking device of the base-threader;

Fig. 5 is a detailed view of the jaws of the wire twisting mechanism, the jaws being shown in an open position; and

Fig. 6 is a further detailed view of the jaws of the wire twisting mechanism of the present invention, the jaws being shown in a closed position.

General layout and operation Understanding of the present invention may be facilitated by a general consideration of Fig. 1 before going more deeply into structural details. In the various figures of the drawings, a convention has been adopted with regard to reference numerals. Numerals of the 100 series refer to the wire twisting portion and reference numerals of the 200 series refer to the base-threading portion of the invention, while numerals less than 100 are applied to elements common to both portions.

A number of fluorescent lamps are shown at the right hand side of Fig. 1 of the drawing. These lamps are indexed along a conveyor 12'by a chain 13 on which the lamps are retained. Lamps reaching the point indicated by the lowermost lamp 14 have been evacuated, gas-filled and tipped. Various electrical operations and checks such as the initial breakdown also are performed prior to the operations which are carried out by the present invention. To all intents and purposes, the lamp 14 is substantially complete but no base has yet been applied.

Electrical connecting members such as the lead wires 15 extend from the lamps and may have been given a preliminary orientation at a previous point to draw them more or less axially outward from the lamps. This preliminary orientation is not essential to proper operation of the present invention, although operation is aided to some extent if the leads are so treated. Apparatus is provided adjacent the conveyor on both sides in order that processing operations may be performed simultaneously at both ends of the lamps as they proceed along the conveyor. In other words, apparatus which is a mirror image of that shown in Fig. 1 is disposed at the opposite ends of the lamps on the other side of the conveyor which is not shown.

The general operation of the present invention is such that as a lamp is indexed into the position occupied by the lamp 16, second from the bottom in the showing of Fig. 1, a pair of jaws are advanced toward the end of the lamp. The jaws are caused to swing open as they are advanced toward the lamp and they are rotated continuously during their entire forward progress. The rotaltion is imparted to the jaws by means of a motor, a reduction gear, and a pair of pulleys joined by a V-belt. The second pulley is pinned to a sleeve on which the jaws are mounted and, in this manner, the jaws are maintained in continuous rotation.

As will be explained in greater detail below with reference to subsequent figures of the drawing, the jaws are advanced by means of a cam driven lever the end of which is slotted to accommodate a trunnion block.

When the rotating jaws in their open position reach a point adjacent the end of the lamp, their forward motion is discontinued.

Retraction of the entire mechanism then occurs in response to continued action of the cam driven lever on the trunnion block. As the retraction begins, the jaws close, seizing upon the lead wires extending from the end of the lamp. The retraction combined with the rotating of the jaws causes the leads to be twisted hclically. Furthermore, the retracting action of the closed jaws draws the helically twisted leads out roughly along the axis of the lamp.

At the next index of the conveyor chain 14, the lamp is carried to the position indicated by the lamp 17 shown third from the bottom in Fig. 1 of the drawing. Here it is desired to thread a base on the helically twisted lead wires which are now prepared to receive it. The base is provided with a contact pin which has a small central opening, and it is desired to pass the twisted leads through that opening.

Now, a rammer shaft having an advancing and retracting motion is used. During the retracting motion, a base is dropped by an escapement device against a stop adjacent the end of the lamp. A vacuum chuck on the end of the base rammer shaft picks the base from the stop and carries it toward the end of the lamp. As the base is moved toward the end of the lamp, it is rotated causing the helically twisted'leads to go easily through the opening in the pin of the base. In this instance, however, in contrast to the action of the lead-twisting device, the rotation of the tool is not continuous. A clutch in the rammer shaft drive disengages as the base approaches the end of the lamp. This is necessary because a small quantity of basing cement is carried around the inner edge of the base and it would be removed or displaced if rotation were to continue when the basing cement comes into contact with the end of the lamp.

Not only is the rotating motion discontinued when the base nears its intended final position on the lamp, but also the vacuum exerted on the base through the hollow shaft is broken by the opening of a port in the shaft adjacent the clutch and the base is merely pressed onto the lamp end. Thus, as the retracting motion of the base-threading mechanism follows, there is no tendency for the base to be withdrawn from the lamp end.

With the aid of the foregoing general explanation of layout and operation, understanding of structural details and specific processing steps of the embodiment of the invention described below should be facilitated.

The wire twisting mechanism The upper most portion of the wire twisting mechanism, amongst other apparatus, is shown in the plan view of Fig. 1. However, the side elevation of Fig. 2 provides a better reference to be used in connection with the description immediately following.

Basic structural support for the entire apparatus is derived from a frame 99 on which a support bracket 100 is bolted. A fulcrum shaft 101 is supported in a downwardly depending extension of a support member which, in turn, is bolted to the bracket 100. A major actuating lever 102 is pivoted on the fulcrum shaft and carries at its end a rotatable cam follower 103 bearing upon a contoured cam 104. A rod 105, spring loaded in a manner explained below, is pivotally attached to the lever 102 adjacent its other or upper end and maintains the follower 103 in contact with the earn 104.

A finger cam 107 is provided on the same shaft as cam 104. A finger cam follower 108 is rotatably attached to a lever 109 and bears upon the finger cam 107. At the other end of the lever 109 there is pivotally attached a finger spring guide 110. The finger spring guide extends through matching openings in the support bracket 100 and in a finger bracket 113 which is bolted to the support bracket 100. At the upper end of the finger bracket 113 is a finger stud 114 about which a finger 115 pivots. A finger stop 117 adjustable in its bearing upon the bracket 113 is provided in a depending portion of the finger.

At the upper end of the finger spring guide 119 a pivotal attachment, not shown, is made to the finger 115. A compression spring 120 disposed between the finger spring cup 119 and the adjustable finger spring collar 121 maintains the finger 115 in the normally raised position in which it is shown, and also tends to hold the follower 108 against the finger cam 107. in its normally raised position, as it is shown, the finger 115 is adjacent the end of the fluorescent lamp 116. The finger thus prevents the lamp 116 from moving to the right off the conveyor bed;

The mechanism for performing the wire twisting funetion also derives basic support from the bracket 100. Bolted to the bracket 100 is a casting 130 at the upper end of which two aligned cylindrical members are formed. The member 131 is at the left and the member 132 at the right as seen in Pg. 2. A third circular opening is formed in the casting at 133 to accommodate the spring rod 105. In a depending portion of the casting 130 a fourth opening is formed for the fulcrum shaft 101.

Bushings are inserted in the cylindrical members 131 and 132. A tubular slide 133 passes through the bushing of the member 131 and a sleeve 134 is carried in the bushing of the member 132. Lubrication is provided for the contacting surfaces'of the slide 133 and the bushing of member 131 by a reservoir assembly 135. An oiling device 136 permits lubrication of the contacting surfaces of the sleeve 134 and the bushing of member 132.

A rod 137 is spring-loaded against the sleeve 134- by means of acompression spring 138. A screw 139 is threaded into a housing 140 to bear against the spring 135 to adjust the pressure that the rod 137 exerts upon the sleeve 134. The'sleev'e 134- has a flanged end against whicha ball bearing assembly 141 is retained by means of a pair of check nuts 142 threaded on the sleeve 134. A housing143 encloses the ball bearing assembly 141 and the housing is'att'ached by means of screws to a pulley 144. A V-b'elt 145 driven by a motor, reduction gears and pulley (see Fig. 1), engages the pulley 144- The pulley 144 is fixed to the tubular slide 133 by a pinor'by a screw threaded into the pulley and bearing on a'fiat in the slide 133. In this manner, rotation is imparted to the tubular slide 133 and to its attached jaw support member 123 on which the jaws are mounted. Dietailsof the support and structure of the jaws are given below in conneetion'with an enlarged view of the jaws and their associated structure. 7

At the' other end of the mechanism, adjustable check nuts 149 are provided at the end of the sleeve 134. A rod end-150 is threaded on the end of the shaft 125 and held in'place by a lock nut. Pivotally attached to the rod end is a trunnion block 151 arranged for sliding actionin a slot 152 formed in the end of the lever 102. An adjustable forward motion limit step 153 designed to contact a surface of the member 132 extends inwardly from a point adjacent the end of the lever 102. The previously mentioned spring rod 105 is pivotally attached to the lever 102 just below the stop 153. The spring rod passes through the opening at 133 in the support 130 and is urged to the left, as seen in Fig. 2, by the action of a compression spring 155 which is held betweena spring cup 156 and the wall surrounding the opening at 133.

At thispoint, an explanation of the operation of this p'o'rtionofthe apparatus with the exception of the details of jaw operation, may be useful to promote understanding of the invention. The cam 104 is rotated continuou 1y by a primary power source, not shown. After a lamp is indexed into position adjacent the wire twister, the finger cam 107 permits the follower 103 to move inwardly to the left as shown in the drawing under the influence of the compression spring 120 which also forces the finer 115 up to the position in which it is shown in Fig. 2. Neglecting for the moment the operation of the wire twisting mechanism, if rotation of the cam 104 continues until the follower 108 is picked up by the plateu of the cam 107, the rod is drawn downwardly to swing the finger downwardly and away from the lamp end against which it abuts. The entire purpose of the finger 116 is to prevent lamps from being drawn endwise off the conveyor during the wire twisting operation.

Clearly, however, the timing of the operation of the finger 115 is critical to prevent interference between the finger, the lamps as they are indexed, and the twisting mechanism. Motions of the conveyor chain, the wire twister and the finger are therefore carefully synchronized by proper cam design and relative rotation.

Reverting to primary functions, the wire twisting operation itself must now be considered. Action is initiated by the eccentricity of the cam 104. As the cam 104 rotates from the position in which it is shown, the cam follower 103 is moved in a generally upward direction. The lever 102 pivots about the fulcrum 101 against the pressure of the compression spring 155. The same spring 155 mantains the follower 103 against the contoured surface of the cam 104 at all times.

Taking the downward movement of the follower 103 into consideration first, the lever 102 pivots about the fulcrum 101 in a counter-clockwise direction. The upward movement of the right hand end of the lever 102 causes the trunnion block 151 to move to the left as shown in the drawing.

Movement of the trunnion block 151 to the left causes a corresponding movement of the shaft 125. As is explained below in connection with the detailed showing and description of the jaws, thse members are forced open against spring pressure. The shaft moves within the sleeve 134 fora distance great enough to open the jaws before the sleeve 134 moves at all. The friction engendered by the rod 137 bearing on the sleeve 134 prevents that sleeve from moving until the shaft 125 has moved as far as the check nuts 149 permit. Movement of the shaft 125 ceases when the check nuts 149 encounter the end of the cylindrical member 132. At this time, the entire rotary mechanism moves to the left, the slide 133 moving in the bushing in the member 131 and the sleeve 134 moving in the bushing in the member 132. The slide 133 is rotated continuously during this movement, as, of course, are the jaws 124 which are held by the jaw support 123 on the slide 133. This leftward movement of the entire rotary mechanism continues until the adjustable stop 153' encounters the end surface of member 132.

At about this time the contoured cam surface begins to carry the cam follower 103 in an upward direction. The lever 102 pivots about the fulcrum shaft 101 and the trunnion block 151 is moved to the right. The first action occurring on the withdrawal of the trunnion block 151 is a movement to the right of the shaft 125, the pressure of the rod 137 on the sleeve 134 inhibiting its movement. Movement of the shaft 125 to the right causes the jaws to close as will be shown and explained in greater detail hcreinbelow. As the jaws close, they seize upon the lead wires 118. Retraction of the slide 133 and the sleeve 134 commences as the trunnion blocks 151 are drawn further to the right by the action of the lever 102.

With the jaws rotating continuously and seized upon the lead wires 113, the retracting movement to the right causes the lead wires to be drawn out and twisted into a helix. Retraction of the entire unit continues until the cam follower 103 reaches the point of greatest radius on the cam 104, at which point the jaws are beyond the furthest extension of the lead wires.

Base threading mechanism After the lead wires have been twisted into a helix in the manner described above, the fluorescent lamp is indexed to a new position indicated by lamp 17 which is shown in the position third from the bottom in Fig. 1. Also, as is shown in Fig. 1, and in some particulars more clearly shown in Fig. 3, a device is provided at this point for completing the basing function by threading bases onto the lead wires which were prepared by the twisting operation performed at the previous position. In Fig. 3 some of the basic structural elements are shown fragmentarily as, for example, the basic support bracket 201 which is attached to the conveyor frame. This bracket can be the same as bracket 100 previously described or may be a separate member. An outward extension of the bracket 201 has bolted to it a support which includes a downwardly depending fulcrum shaft bearing member 203. A fulcrum shaft 204 is held in the member 203 and provides a pivot for the cam lever 206. The lower portion of the cam lever 206 carries a cam follower 208 which bears upon a contoured cam 209. The cam 209 may have a slightly roughened surface for purposes explained below. A spring lever 210 is bolted to the lower portion of the cam lever 206 and a tension spring 212 is attached to the end of the spring lever 210 to retain the cam follower 208 in contact with the contoured surface of the cam 209. The upper end of cam lever arm 206 is provided with a catch 214, a stop surface 216 and a yoke 218. A latch 220 designed to cooperate with the catch 214 is normally held from engagement with the catch by a tension spring 222 which is stretched between the end of the latch and a pin in an arm 224 of the support member. A solenoid 226 is retained on the extending portion of the bracket 201 by means of a plate 228 which is bolted to the bracket. The solenoid has a shaft 230 extending outwardly from its core and attached pivotally to the latch 220. A motor support 232 which may be independent or derive its basic support from the conveyor frame, carries a motor 234 which drives a pulley 235 through a reduction gear 236. A V-belt 238 connects the drive pulley 235 to a second driven pulley 240.

A vacuum line 241 is connected at the left end of a base rammer shaft 242. The base rammer shaft 242 is hollow throughout its entire length permitting the vacuum to be exerted at the end adjacent the lamp 245. A vacuum line support 246 extends outwardly from the basic support arm 224 and retains the vacuum line 241 in its proper position. Means are provided to break the vacuum in the base rammer shaft at a point intermediate its length as is illustrated in another figure of the drawing and described in detail below.

A feeder sleeve 248 surrounds the base rammer shaft and has a threaded end on which a check nut 249 is adjustably engaged. The upper end of the arm 224 terminates in a cylindrical member 250 which serves as the base feed bracket. To the right of the base feed bracket as seen in the drawing is a heavy compression spring 251. A thrust bearing 252 is provided between the compression spring and the previously mentioned pulley 240. These three elements are mounted upon the feeder sleeve 248 which has a flanged end against which the pulley abuts. To the right of the pulley 240 is a clutch mechanism which includes a clutch shoe 254 and a flanged clutch collar 256. The base rammer shaft 242 as shown in the drawing is provided with a flat against which a screw through the clutch collar bears to maintain the collar fixed against rotation relative to the base rammer shaft.

At the upper left of Fig. 3 (and more clearly and in enlarged detail in the same area of Fig. 4), is a base supply guide 257. Along this guide, a supply of bases 258 are led to where they are presented to a chuck 261 at the end of the base rammer shaft 242. The bases are circular in shape and a pair of spaced stop fingers of which finger 260 is typical are provided to serve as an escapement mechanism. The two fingers go between the two lowermost bases at either side of their point of contact.

In the yoke 218 of the cam lever arm, a trunnion pin 262 is disposed for sliding movement. The trunnion pin is pivotally attached to the base rammer shaft 242 by means of a clamping device and is also connected to an overtravel mechanism. The overtravel mechanism includes a tension spring 264 which is stretched between the base feed guide 257 and a spring plate 265. A cap screw 266 is provided to adjust the position of the spring plate 265 and thereby to adjust the tension of the spring 264. The overtravel function is explained in greater detail hereinbelow, its function being accomplished primarily by the positioning of a shoulder screw 270 in the slot 271 of the mechanism.

The extent of forward movement of the lever arm 206 is controlled by an adjustable cap screw 272 against which the stop surface 216 strikes at the furthest forward point of movement of the upper portion of the lever arm 206.

An explanation of the phase of the basing operation for which the apparatus described immediately above is responsible may help in understanding the invention. When a lamp is indexed into the position at which lamp 245 is shown in Fig. 3 of the drawing, the base threading operation begins. The existing conditions include a vacuum being drawn through the vacuum connection 141 and extending through the entire length of the base rammer shaft 242 to the base holding chuck 261. Also, the motor 234 is operating, causing the pulley 236 to drive the pulley 240 rotating the base rammer shaft and its associated components. The base guide member 257 is filled with bases, one of which rests against the base stop 259. Furthermore, the solenoid 226 is de-energized, causing the latch 220 to be out of engagement with the catch 214 as shown in the drawing. A microswitch or similar device, not shown, is disposed upon the conveyor and is so arranged that the energizing circuit to the solenoid 226 remains open as long as fluorescent lamps are being indexed along the conveyor. In the absence of a lamp, the switch is not tripped, causing the solenoid energizing circuit to remain closed and the latch 220 to engage the catch 214 thereby preventing the lever arm 206 from moving about the fulcrum 204. The cam follower 208 is shown in a position adjacent the greatest radius of the cam 209. After the roller 208 passes over the portion of greatest radius of the cam 209, the tension spring 212 draws the spring lever 210 and the cam lever 206 downward and to the left as shown in the drawing. The portion of the periphery of the cam 209 which the follower 208 traverses at this time may be slightly roughened to give a slight vibration to the cam lever 206. As the device pivots about the fulcrum 204, the upper forked end of the lever arm 218 begins to move to the right. The base holding chuck 261 encounters a base 258 resting on the base stop 259 and the base so encountered is held in the base chuck by reason of the vacuum existing throughout the length of the base rammer shaft. Rotation of the base rammer shaft continues as the shaft moves to the right and a very light vibration of the shaft also occurs because of the roughened surface of the cam 209. The vibration aids in passing the lead wires of the lamp through the opening in the base 258.

The fingers 260 pass between the two lowermost bases on the guide 257 until the fingers contact the front portion of the guide. The clutch shoe 254 remains in intimate contact with the pulley 240 by reason of the pressure exerted by the compression spring 251 on the thrust bearing 252.

When the fingers 260 encounter the front portion of the base guide 257, the overtravel mechanism comes into play, as is most easily seen in Fig. 4. Further movement of the trunnion 262 to the right is not effective to move the finger 260 to the right. Instead, the finger support plate moves forward guided by the shoulder screw 27% which is disposed in the slot 271 in the support memher.

When the check nut 249 strikes the left hand surface of the feeder member 250, travel of the clutch sleeve 24% ceases. The clutch shoe 254 breaks from the surface of the pulley 240 and rotation of the base rammer shaft ceases. This occurs just prior to seating of the base 258 on the end of the lamp 245. Thus, as the base rammer shaft continues to the right, the base is merely jammed on the end of the lamp and not rotated relative to the lamp end. Simultaneously with the breaking of the clutch, the vacuum within the base rammer shaft is broken by means of a port 243 extending radially through the shaft adjacent the break point of the clutch as shown in Fig. 4A. The clutch is shown in solid lines in its engaged position and in dashed lines in its disengaged positon. The port 243 is similarly shown and it'will be noted that the port is open to atmospheric pressure when the clutch is disengaged. Thus, there is no tendency for the base to be retracted from the lamp when the base rammer shaft is retracted as described below.

As the cam 209 continues its rotation and the radius increases, the cam follower 208 causes the upper portion of the lever arm 206 to move to the left to retract the base rammer shaft. This action continues until the clutch is reengaged. The finger 260 is retracted and another base drops into position against the base stop 259 awaiting the next thrust of the base rammer shaft when a new lamp has indexed into position.

Description and operation of jaws The structure and operation of the jaws which prepare the lead wires for basing by twisting them and drawing them out along the axis of the lamp may best be understood by referring to the enlarged showings of this device in Figs. 5 and 6. In Fig. 5, the jaws are shown in the open position which they assume as their advance toward the lamp takes place. As was previously explained in connection with the view of the entire wire twisting mechanism, a jaw support member 123 is attached at the end of the tubular slide 133. The tubular slide is provided with a pair of flats on its outer surface which are 90 degrees apart and which are engaged by lock screws passing through the jaw support at corresponding points.

As may be seen in Fig. 2, a pair of radial slots are cut in diametrically opposite areas of one face of the disk shaped jaw support member 123. In these slots, there are welded a pair of arms 161 and 162. These arms extend parallel to the axis of the support and terminate in rounded ends which are bored to accommodate fulcrum screws 163 and 164. Pivoted about each fulcrum screw is a jaw lever composed of an arm and a holder welded together at an obtuse angle. The levers are similar and the bottom lever, as seen in Figs. 5 and 6, includes the arm 166 and the holder 167. The top lever includes the arm 168 and the holder 169.

Bolted to the arm 166 is a bushing 170 which may be eccentrically mounted for ease of operation. A similar bushing and bolting arrangement exists for the arm 168, but is hidden in the drawing. These bushings, one above the shaft 125 and the other'below it, are designed to be contacted by a pair of contact disks 171 and 172 which are locked to the shaft 125.

A tension spring 173 extends between pins or bolts on the holders 167 and 169, respectively, and tends to hold them in the position shown in Fig. 6. At the end of the holder 167, there is bolted an L-shaped gripper 175 and a similar gripper 176 is bolted to the holder 16 9. Both grippers have forked ends, and the gripper 176 has its forward end relieved to permit the passage of the gripper 175 during the closing movement.

The jaw operation is fairly obvious from the drawing. With the advance of the shaft (to the left as' shown in the drawing) the disk 171 contacts the upper and lower bushings on the arms 166 and 168 pushing them forward and openings the jaws as the levers pivot about their fulcrums 163 and 164. Similarly, when the shaft 125 retracts (to the right, as shown) the contact disk 172 contacts the bushings and thus pulls the jaws shut.

Although What has been shown is a preferred embodiment of the invention, numerous modifications within the scope of the invention will immediately suggest themselves to those skilled in the art. Hence, the invention should be limited only as required by the breadth of the appended claims.

What is claimed is:

1. Basing machinery for affixing a base having an opening formed therethrough to a lamp having at least a pair of leads extending outwardly therefrom comprising jaws for seizing said leads, means for rotating and retracting said jaws from said lamp to form said leads substantially into a helix, a chuck for holding said base and means for rotating and advancing said chuck toward said lamp to thread said helically formed leads through said opening formed in said base.

2. Basing machinery for affixing a base having an opening formed therethrough to a lamp having at least a pair of leads extending outwardly therefrom comprising jaws for seizing said leads, means for rotating and retracting said jaws from said lamp to form said leads substantially into a helix, a hollow chuck, means for applying a vacuum to said chuck to hold said base therein, means for rotating and advancing said chuck toward said lamp to thread said helically formed leads through said opening formed in said base, and means for discontinuing said vacuum to said chuck to release said base therefrom adjacent said lamp.

3. Basing machinery for affixing a base to the end of a lamp from which a pair of leads extend, said base having an opening formed therethrough, comprising a lead preparing station, a base threading station, and means for indexing lamps sequentially to said stations, said lead preparing station including a pair of jaws, means for continuously rotating said jaws, means for advancing said jaws in open position toward said lamp end, means for closing said jaws to seize upon said leads, means for rotating and retracting said jaws from said lamp end to form said leads substantially helically, said base threading station including a hollow chuck, an escapement mechanism for supplying bases one at a time to said chuck, means for applying a vacuum to said hollow chuck to retain a base therein, means for rotating and advancing said chuck toward said lamp end to thread said helically formed leads through said opening in said base, and means for disconnecting said vacuum from said chuck to release said base as said chuck approaches said lamp end.

4. Basing machinery for afiixing a base to the end of a lamp from which a pair of leads extend, said base having an opening formed therethrough, comprising a conveyor for said lamps, a lead preparing station and a base threading station, said lead threading station being disposed adjacent said conveyor at a first point, means for indexing said lamps one after another along said conveyor to said first point, each said lamp dwelling at said first point for a predetermined period of time, a pair of jaws, a reciprocating support therefor, and means for continuously rotating said jaws included in .said lead preparing station, means within said reciprocating support for opening said jaws, advancing said jaws toward a lamp dwelling at said first point, closing said jaws upon said leads, and retracting said jaws, the retraction and rotation of said jaws causing said leads to be twisted helically and drawn outwardly from said lamp, means for indexing said lamps one after another along said conveyor to a second point, said base threading station being adjacent said second point, each said lamp dwelling at said second point for said predetermined period of time, a hollow shaft, a vacuum line connected to one end of said shaft, and a chuck at the other end of said shaft for holding a base by means of said vacuum, a supply of bases adjacent said other end of said shaft, an escapement mechanism at said supply of bases for presenting bases one at a time to said chuck, means for rotating and advancing said shaft toward a lamp dwelling at said second point on said conveyor, said chuck encountering and holding a base during its advance, the advance and rotation of said shaft and chuck threading a base upon said helically twisted leads during the dwelling of a lamp at said second point, a clutch in the rotating means for said shaft, and means for disengaging said clutch to terminate rotation of said shaft as the base approaches the end of the lamp on which it is being threaded.

5. Apparatus as in claim 4 wherein a port is formed in said shaft adjacent said clutch, said port being opened to air pressure by disengagement of said clutch to break the vacuum from said vacuum line to said chuck.

6. Apparatus as in claim 4 wherein said means for rotating said hollow shaft includes a cam having a 7. Basing machinery for afiixing a base to the end of a lamp from which a pair of leads extend, said base having an opening formed therethrough, comprising means for twisting said leads together into a substantially helical configuration, a hollow chuck, means for applying a vacuum to said chuck to retain a base therein, means for rotating and advancing said chuck to thread said helically formed wires through the opening in said base, means for substantially simultaneously breaking said vacuum in said hollow chuck and discontinuing the rotation of said chuck as said base approaches said end of said lamp to release said base from said chuck and to prevent rotation of said base relative to said end of said lamp as said base approaches contact therewith.

8. Apparatus as in claim 7 wherein said means for rotating and advancing said chuck includes means for imparting a light vibration to said base to expedite the threading of said leads through said opening in said base.

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