US2429203A - Mercury doser - Google Patents

Description

Oct. 21, 1947.

G A. FREEMAN ET AL MERCURY DOSER Filed March 17, 1942 I NVENTORS H. I (UNA/IV 6+". 14. BEE/141V BY WARM W,

ATTORNEY Patented Oct. 21,1947

MERCURY DOSER George A. Freeman, East Orange, N. J., and Howard J. Conlin, Fairmont, W. Va, assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application March 17, 1942, Serial No. 435,020

g 12 Claims. (01. 222-357) This invention relates to electric lamp manufacture, and more particularly to gas charging apparatus, which, in the present embodiment, is specifically a mercury doser for lamps utilizing mercury vapor.

In the electric art which includes not only lamps but also electronic devices, the use of mercury within lamp, tube or other device becomes increasingly prevalent. An outstanding present use is in fluorescent lamps. The amount of mercury required and used in a lamp is dependent upon the size of the lamp, and for some of the smaller lamps the mercury dosage is so small that the usual mechanical valve type of closer introduces too great an error in operation. When it is realized that mercury used in some of the smaller lamps is about the size of an ordinary pin-head, and that mercury exhibits a tenacious surface tension, the difiiculty of withdrawing from the body of mercury an assured amount of that minute size each time it is wanted can be appreciated.

An object of the invention is to overcome the insufiiciencies of prior art dosers.

A further object is to accurately measure the dosage of mercury. A

Another object is to provide means which will accurately measure a minute dosage of mercury.

Yet another object of the invention is to provide a means operable in a vacuum, one that is visual to the operator, and responsive to magnetic contro..

Still further objects of the invention will appear to those skilled in the art as the description progresses, both by direct statement thereof and by implication from the context.

In the accompanying drawing, wherein like numerals of reference indicate similar parts throughout the several Views, and wherein a preferred physical embodiment of the invention is disclosed by way of example:

Figure 1 is an elevational section of our improved mercury doser;

Figure 21s a perspective view of the dosing shuttle; and

Figure 3 is a sectional view of said shuttle.

In the specific embodiment of the invention illustrated in said drawing, the reference numeral I ll designates the mercury doser body portion which is preferably a tube of inverted J-shape of which the short leg H is closed at its bottom i2 thereby forming a container or reservoir for a mercury supply l3. As this body portion is in an upright position, mercury in the reservoir portion ll thereof remains therein until intermit --tent1y removed in operation in minute doses. The

body portion provides an interior passage from one leg to the other. The said body portion is furthermore preferably clear glass in order that the quantity and level of mercury may be readil observed, and, as will later appear herein, that the shuttle may be observed.

The long leg Id of the body portion of the mercury doser is likewise vertical, and below the curved joining upper portion I5 connecting the legs, said long leg provides a shuttle stop It. A convenient and desirable construction for said stop is obtained by forming a peripheral constriction in the tubular wall of the leg in the vertical portion thereof. By this construction, the stop is next the wall of the tube leaving a central opening through the same. Below this stop it, a T-branch ll forms appropriate connection to the vacuum pump (not shown). Still further below, the tube contracts at l8 to appropriately join with the lamp tubulation and lamp bulb I9.

In order to pick up and transfer a measured minute dosage of mercury from the reservoir supply !3 to the lamp, we provide a shuttle 26 detail structure of a preferred form of which is shown in Figures 2 and 3. Said shuttle comprises a disc-like or other head 2! of iron or other material responsive as an armature to an electro or other "magnet 22.

Said head is loose within the tubular body portion to an extent permitting passage of mercury therearound, and to keep it approximately normal to the wall of the said body portion wherever situated at the moment, the disc-like head has a guiding tail the specific form of which is of an open character and shown of wire formation. Thus, the tail shown comprises a single piece of wire the end portions 23, 23 whereof are parallel and extend into the disc-like head parallel to the axis thereof. The said end portions of the wire forming the tail are suitably secured in the disc-like head to remain permanently fixed with respect thereto. Furthermore said end portions of the wire are situated quite close to the periphery of the head so as to be close to the walls of the tube in use. The mid-portion of the wire forming the tail is bent into a plane parallel to the disc-like head and provides extended arcuate portions 25, 24 in said plane with radius of curvature substantially equal to that of the head. The arcuate portions are diametrically opposed to each other and at their extremities most distant from the ends of the wire, are joined by a substantially diametrically disposed portion 2 5 of the wire.

reservoir portion thereof to an inverted position in another portion of said passageway for picking up and discharging mercury doses, and an external magnet movable in parallelism to the said passageway and effective on said means for moving the same back and forth in the passageway from one portion thereof to another.

8. A mercury doser comprising an inverted J- shaped body portion of which the short leg constitutes a reservoir and the long leg constitutes a discharge passage, means in said body portion transferable from within one leg thereof to the other and free of external mechanical attachment for picking up mercury in the reservoir leg and discharging the mercury in the discharge passage upon transfer of said means into said discharge passage, and external electro-magnetic means movable contiguous to and along said body portion and effective on said means in the body portion to move the same correspondingly within the body portion as the said electro-magnetic means moves longitudinally at the exterior of the body portion.

9. A mercury doser comprising a body portion having an inverting passageway one part whereof constitutes a mercury reservoir and another part constitutes a, discharge passage, a shuttle transferable from within one leg of the body portion to the other and free of external mechanical attachment and loosely slidable in said passageway and adapted to be submerged in the mercury right side up and thereby receive a dose of mercury, said shuttle being movable to an upside down position in the discharge passage for discharge of the dose of mercury received from the reservoir, and magnetic means outside the body portion and effective therethrough on said shuttle for operating the shuttle from submerged position to upside down position and back again.

10. A mercury doser comprising a body portion formed with a passageway having a curved portion and at opposite ends thereof having depending portions, one of said depending portions being closed at the bottom and constituting a mercury reservoir, a huttle slidable in said passageway from upwardly directed position in the mercury reservoir portion thereof to an inverted position in another portion of said passageway, said shuttle having means adapted to receive and retain a dose of mercury while the shuttle is upright in the reservoir portion of the passageway and to carry said dose of mercury as the shuttle passes to the other depending portion of the passageway, and an external magnet movable adjacent said passageway and efiective on said shuttle for moving the same back and forth in the passageway from one portion thereof to another, whereby a dose of mercury may be picked up in one portion of the passageway and transferred free from the mercury in the reservoir by said shuttle and discharged in another position of the passageway.

"ing portions, one of said depending portions bev ing closed at the bottom and constituting a mercury reservoir, a shuttle slidable in said passageway from upwardly directed position in the mercury reservoir portion thereof to an inverted position in another portion of said passageway, said shuttle having a head and a tail by which the shuttle is guided longitudinally of said passageway and said shuttle having means adapted to receive and retain a dose of mercury while the shuttle is upright in the reservoir portion of the passageway and to carry said dose of mercury as the shuttle passes to the other depending portion of the passageway, and an external magnet movable adjacent said passageway and effective on said shuttle for moving the same back and forth in the passageway from one portion thereof to another, whereby a dose of mercury may be picked up in one portion of the passageway and transferred free from the mercury in the reservoir by said shuttle and discharged in another position of the passageway.

12. A mercury doser comprising a body portion having a hermetically closable passageway of substantially uniform cross-section throughout its length, said passageway having one part thereof vertically upright and closed at its bottom for constituting a mercury reservoir and having another part extending vertically downward for constituting a discharge passage, said passageway having an intermediate and uppermost part thereof curved downwardly and in connecting continuation of both said vertically positioned parts, and a magnetic cup transfer mechanism loosely slidable in said passageway and in all of said parts of said passageway and constructed and arranged to be submerged in the mercury,

- the upper side of the cup transfer mechanism having a, cavity therein for receiving a mercury dose, and said cup transfer mechanism being,

movable from an upright position in said reservoir and through said passageway to an upside down position in the discharge passage with said cavity then directed vertically downward for discharge of the dose of mercury therein.

GEORGE A. FREEMAN. HOWARD J. CONLIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number

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