US2847699A - Lamp basing head - Google Patents

Description

1958 D. MULLAN ETAL 2,847,699

VLAMP BASING HEAD 2 Sheets-Sheet 2 Filed March 31, 1953 4% w% M Z m W 4w I. 5 PM United States Patent fitice LAMP 'BASING HEAD Daniel Mullan, Hillside,and Edward Z. Zilahy, Nut ley, N. J., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application March 31, 1953, Serial No. 345,962

6 Claims. (Cl. 18-1) This invention relates to machines for manufacturing electrical devices and is more particularly directed to the mechanism generally identified. in the trade as a basing head.

in the manufacture of electrical devices, such as lamps or the like, which comprise a sealed envelope and a base portion, it is necessary to provide mechanism for securing the base to the envelope or bulb. The operation of at taching a base to a bulb includes the positioning of the base on the tip-turned basal end of the bulb and utilization of an interposed quantity of basing cement. The assembly is then longitudinally compressed in the basing head of the machine and passed through an oven to obtain setting of the cement and permanent attachment of the base to the bulb. Heretofore an operator has been required to properly locate the bulb and base in the basing head while the cement is still soft so as to obtain axial alignment of bulb and base before clamping the assembly. The individual operator attention thusrequired has not been conducive to high speed manufacture.

Broadly stated, the present invention contemplates a structure of basing head by which basing may be accomplished at high speed.

Likewise in its broadaspect, the invention proposes automatic positioning ofthe bulb and base assembly in the basinghead.

More specifically, an object of the invention is to utilize gravity to influence stable bulb location in a temporary loaded position before clamping. becomes effective.

A further objectof the invention is to provide automatic mechanical means to obtain axial alignment of the bulb and base.

Another object of the invention is to utilize the pressure clamping of the bulb and base to both right the assembly from its gravitationaltemporary location and to obtain the aforementioned axial alignment.

Still other objects of the invention will become ap* parent to persons skilled in the art to which it appertains as the description proceeds, both by directrecitation thereof and by implication from the context.

Referring to the accompanying drawings, in which like numerals of reference indicate similar parts throughout the several views:

Figure 1 is an elevation, partially in section, of a basing head in loading position and showing, by dotted lines, a bulb and base assembly inits temporary gravitational location as loaded;

Figure 2 is a longitudinal sectional view of the basing head and showing the bulb and base assembly. in axially aligned loaded position;

Figure 3 is a perspective view of the basing head approaching position of discharge;

Figure 4 is a plan of the basing head; and

Figure 5 is a fragmentary sectional view on increased scale of the upper seating end of the basing head as shown in Fig. 2.

In the specific embodiment of the invention illustrated in said drawings, the basing head therein shown will be in succession through a cycle from loading position back to discharge position. Those positions are closely related so that as soon as a lamp or similar article desig nated by numeral 10, is discharged from the particular head, it is forthwith replaced by a lamp assembly to be worked upon through the same cycle. The lamp comprises essentially a sealedbulo or envelope 11 having a neck end adaptedto receive a metal base 12 thereon. Initially a soft cement is interposed between the envelope and base permitting limited adjustment by virtue of which the base may be brought to axial coincidence with the bulb axis. Thereafter, in the cycle of operation, the lamp assembly is baked to harden the cement and finally the lamp is discharged from the head and the operation repeated with another lamp assembly.

It will be evident from the above that it is necessary to provide suitable means whereby the base is properly aligned with respect to the bulb so that. when the two parts become a unitary structure they will have the desired symmetrical appearance. In the prior art where the lamp assemblies were placed by hand in the basing angle to the axis of its ultimate clamped position. Advancement of the lamp assembly is utilized to straighten up. the lamp assembly to properly address the base end to the fixed clamping ledge. After the lamp assembly is thus straightened up, it is automatically centered and pressed longitudinally. The pressingoperatesto also align the axis of the bulb with the axis of the base, and while thus held throughout the remainder of the cycle, it is baked, the cement hardens and permanent symmetrical assembly of the lamp thus has a base and bulb.

The mechanism employed in accomplishing the abovedescribedoperations includes a bulb-receiving, centering and. supporting member 15 having the configuration of an inverted tripod thereby providing three. downwardly converging arms 16 withinwardly facing surfaces afford ing a centering support for the globular endof the lamp assembly. These arms are evenly spaced angularly of the axis with the spread between two arms toward What will be termed the front of the head and the third arm directed toward the rear of the head, the front spread of the arms being conducive to most convenient introduction of a lamp assembly into the supporting member as well as discharge of the lamp therefrom at the end of the cycle.

Said centering and supporting member 15 is fixed, as by a shoulder 1'7 thereunder and set screw 13 to the upper end of a slide rod 19 movable vertically in appropriate spaced bearing lugs 20 of a bracket 21 which is carried by the machine or its conveyor as well understoodin the art.

The rod 19 and its member 15 are spring loaded upwardly in. any convenient manner. According to the present showing, an adjustable winged collar 22 is mounted on said rod between the bearing lugs. and has upward resilient impetus applied thereto by a spring 23 thereunder. The spring is conveniently coaxially mountedon said rod and supported at its bottom by the lower bearing lug 20. Adjustment of the winged collar is obtained by provision of aplurality of diametric holes 24 in the,

Patented Aug. 19, s

The construction is such that the lamp 1s first placed in a temporary stable position under gravitational influence with the lamp axis at an i to its clamped position .3 rod and selected use thereof by a pin 25 insertable diametrically through the collar. At one end of said pin is a transverse latch 26 which can be swung down into a keeper 27 to hold the pin from sliding out inadvertently. The pin is shown in the drawings as applied in the uppermost hole of the rod so the bulb supporting member 15 is at its lowest adjustment for receiving a large lamp assembly. For smaller lamps the collar would be adjusted to apply the pin in an appropriate one of the lower holes 24.

As a further function of said winged collar, one of the wings thereof, designated by numeral 28 has a forked outer end adapted to ride on a guide 29 parallel to rod 19 to keep the collar and rod from rotating. The other wing, identified by numeral 30 has the characteristic of a boss carrying a roller 31 by means of a stud 32 constituting the bearing for said roller. The axis of the roller is perpendicular to the axis of rod 19. The machine provides a horizontally disposed bar cam 33 having a downwardly sloping surface to be engaged by said roller. This bar cam has a length which functions during the discharge and reloading portion of the cycle of the machine operation. It will be understood that as soon as a completed lamp is discharged, a new assembly to be worked upon by the machine is immediately inserted in the emptied basing head. The far end of the cam (not shown) is preferably also tapered as shown for the near end so the rod and lamp support have a sufficiently gradual rise under influence of the spring 23 to avoid injury to the glass bulb.

An important features of the present invention is provision of means for receiving, locating, aligning and seating the base end of the lamp assembly. As the machine operates with the base end of the lamps projecting upwardly, reference to the upper end of the lamp herein a synonymous with base end thereof.

The basing head bracket 21 is here shown having a shape in general a segmental part of a cylinder coaxial with the axis of rod 19 and projecting upward from the level of the upper lug 20. The upper end of the bracket is flanged, as at 34, and on this flange is secured a cap 35 the front of which is cut away thereby providing an opening to permit lateral introduction of the upper end of the lamp assembly. The inside face of this cap 35 is substantially frusto conical or otherwise sloped from a bottom large diameter to an upper smaller diameter. The front edges of this cap where cut away likewise slope in such manner that the cut-away at the bottom of the cap is more than an angle of 180, whereas the cut-away at the top of the cap is less than an angle of 180. Furthermore, the diameter of the inside surface of the cap at its upper end is substantially the diameter of the base. Thus when the base approaches proximity to the upper end of the cap, it cannot fall forwardly out of the cap opening, but when the base is closer to the bottom of the cap, there is ample opening for its insertion and removal in a lateral direction through the opening.

The upper end of cap 35, has its inside surface a continuation of the slope heretofore mentioned, of dimension and shape to constitute a ledge 36 with which the end rim of the base comes into centered and seated engagement when the lamp assembly is pushed upward thereagainst. The cap is upwardly open within the inner circumference of the ledge so the central end portion of the base is accessible as the lamp passes through its cycle in the machine.

In operation, a lamp assembly in which the cement has not yet hardened, is applied in the basing head with the bulbous envelope resting on the three arms 16 of supporting member'15. At the time of introducing the assembly to the basing head, the rod 19 and member 15 are held in lowered position by cam 33 and roller 31. The lamp assembly may therefore be tilted, as shown in Fig. l, with the back edge of the base 12 leaning against the tapered inner surface of cap 35. Since this tilting of the lamp assembly moves its center of gravity back of the axis of rod 19, gravitational influence will function to keep the lamp assembly tilted, and due to the curvature of cap 35, the lamp assembly cannot roll sidewise. As cam 33 releases the rod 19 to rise, the edge of the lamp base where leaning against the cap surface will be slid up that surface until the base seats upon ledge 36. The ledge requires the base to nest coaxially therein so the assembly therefore is axially aligned and the base pressed against the cement and bulb in ultimate position where it becomes permanently assembled during the remainder of the cycle of the machine.

It may be appropriate to make mention of the fact that as the assembly is lifted and the base slides on the sloping surface of the cap straightening up the lamp assembly, the center of gravity moves to the front, but before it attains coincidence with the axis of the rod, the base has so far risen in the cap as to be within the part thereof where the opening is less than and consequently there is no possibility of the lamp assembly being able to tilt forwardly out of the basing head as a result of its upward forward movement. At the end of the cycle, as the support member 15 and lamp it move downward due to action of cam 33, the lamp is then tilted forward, by an air jet or otherwise, thereby unloading the basing head ready to immediately receive a new assembly.

We claim:

1. A basing head for holding a bulb and base assembly comprising means for supporting said assembly by its bulbous portion, means opposite said supporting means for engaging said base, and means for moving said supporting means and base-engaging means toward and away from each other into positions of clamping and loading respectively, said base-engaging means comprising a caplike member contoured to define an arcuate surface convergent in a direction away from said supporting means and terminating in a ledge, said cap-like member having an opening therein opposite said arcuate surface and contoured to permit the basal end portion of said assembly to be laterally inserted into and removed from said caplike member when said supporting means and cap-like member are disposed in loading position but prevent its withdrawal after said moving means have been actuated preparatory to clamping, and said supporting means and cap-like member being spaced and movable along an axis such that said assembly, when in loaded position on said supporting means, is retained within said basing head, and the base of said loaded assembly, upon the movement of said supporting means and cap-like member toward each other, slidingly contacts and is continuously guided by said arcuate surface toward said ledge into seated engagement therewith and subsequently clamped in predetermined relation with said bulb.,

2. A basing head for holding the base and bulb of a partly fabricated lamp assembly comprising a retractable support adapted to receive the bulbous end of said lamp assembly, and a cap-like member opposite said support engageable by said base and disposed to maintain said lamp assembly in upstanding position, said caplike member having a tapered opening and defining an arcuate surface opposite said opening, said arcuate surface being convergent in a direction away from said support and terminating in a ledge, said opening extending longitudinally of said cap-like member from its larger end and being tapered toward said ledge and proportioned to permit said lamp assembly to be laterally inserted into and removed from said basing head when said support is retracted but prevent its withdrawal after said lamp assembly and support have been advanced a predetermined distance toward said ledge, the slope of said arcuate surface being such that the portion of said surface away from said ledge is offset from the axial line of movement of said support distances such that a lamp assembly, when placed on said support and having its basal end 5 portion in contact with said arcuate surface, will lean away from said axial line and thus be gravitationally retained within said basing head until said lamp assembly has been advanced toward said ledge said predetermined distance and is mechanically retained by said cap-like member.

3. A basing head for holding the base and bulb of a partly fabricated lamp assembly comprising a support movable along a vertical axis between loading and clamping positions and adapted to laterally receive the bulbous end of said lamp assembly, a cap disposed above said support and spaced therefrom along said vertical axis to engage the basal end portion of said lamp assembly, said cap defining an arcuate surface convergent upwardly away from said support and terminating in an annular ledge coaxial with the axial line of movement of said support and contoured to nestingly receive and provide a seat for the free end of said base, a part of said cap being removed to provide an opening that extends upwardly from the bottom of said cap, said opening being tapered upwardly and proportioned to permit said lamp assembly to be laterally inserted into and removed from said basing head when said support is in loading position but prevent its withdrawal after said lamp assembly and support have been advanced a predetermined distance toward said ledge, said arcuate surface away from said ledge and opposite the part of said opening proportioned to permit the lateral passage of said lamp assembly being spaced from the axial line of movement of said support distances greater thanthe radius of said ledge so that a lamp assembly, when initially loaded on said support and having its basal end portion in contact with said arcuate surface, will lean away from said axial line of movement and be gravitationally retained within said basing head, and means for actuating said support upwardly toward said cap and sliding the basal end portion of said loaded lamp assembly along said arcuate surface toward and into seated engagement with said ledge to thus straighten said lamp assembly from its gravitationally-stabilized loaded position and clamp said base in coaxial alignment with said bulb.

4. In a basing head for compressively clamping and holding a base and bulb assembly in predetermined relation, base-engaging means comprising a cap-like member having a front portion and an interior contoured to provide a surface of conical configuration tapered toward and terminating in a ledge, the inner dimension of said cap-like member at said ledge being substantially the same as that of the free end of said base, said front portion having an opening therein extending longitudinally of said cap-like member and being tapered in a direction toward said ledge from a dimension greater than the width of said'base to a dimension less than the width of said base to thuspermit the basal end portion of an assembly to be laterally inserted into and removed from said cap-like member and be mechanically retained therein, said cap-like member being of suflicient length that when in its position of use in said basing head the base of an assembly loaded therein will be continuously guided seated engagement therewith.

5. In a basing head for aligning and compressively clamping the bulb and base of a partly fabricated lamp assembly, base-engaging means comprising a cap having a front portion and an interior contoured to define a frusto conical surface tapered toward and terminating in a ledge, said ledge being coaxial with the longitudinal axis of said cap and contoured to nestingly receive the basal end of said lamp assembly, an opening in said front portion extending longitudinally of said cap and being-tapered in a direction toward said ledge from a dimension greater than the width of said basal end portion to a dimension less than the width of said basal end portion to thus permit a lamp assembly to be laterally inserted into and removed 7 from said head and be mechanically retained therein, said cap being of suflicient length that when in its position of use in said basing head the base of a lamp assembly loaded therein will be continuously guided from its inserted position toward said ledge into seated engagement therewith and clamped in coaxially-aligned relation with said bulb.

6. In a basing head for aligning and compressively clamping the bulb and base of a partly fabricated lamp assembly along a vertical axis, base-engaging means comprising a cap having a front portion and an interior contoured to define a frusto conical surface tapered toward and terminating in an annular ledge, said annular ledge being coaxial with the longitudinal axis of said cap and contoured to nestingly receive the end of said base, the inside diameter of said cap at said ledge being substantially that of the free end of said base, an opening in the front portion of said cap which extends longitudinally thereof from its larger end, said opening being tapered toward said ledge from a circumferential angle of more than 180 at the larger end of said cap to an angle of less than 180 at said ledge to thus permit the basal end portion of a lamp assembly to be laterally introduced into and removed from said cap and be mechanically retained therein proximate and at said ledge, the inner face of said cap opposite the portion of said opening adapted to permit the lateral passage of said basal end portion be ing spaced from the longitudinal axis of said cap distances greater than the radius of the interior of said cap at said ledge, said cap being of sufficient length that when in its position of use in said basing head a lamp assembly loaded therein and having its basal end portion placed in contact with said surface will be gravitationally retained 7 within said head and the base of said loaded assembly continuously guided from its inserted position toward said ledge into seated engagement therewith and clamped in coaxially-aligned relation with said bulb.

References Cited in the file of this patent UNITED STATES PATENTS 835,377 Swan Nov. 6, 1906 935,503 Hetherington Sept. 28, 1909 1,826,505 Conn Oct. 6, 1931

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