US786231A - Electric lamp. - Google Patents

Description

PATENTED MAR. 28, 1905.

P. MCDONNELL.

ELECTRIC LAMP.

APPLICATION FILED JAN. 5, 1905.

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Patented March 28, 1905.

UNITED STATES PATENT OEETCE.

GEORGE P. MGDONNELL, OF ST. LOUIS, MISSOURI, ASSIGNOR TO AMERI- CAN ELECTRIC COMPANY, OF EAST ORANGE, NE\V JERSEY, A CORPO- RATION OF NEW JERSEY.

ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 786,231, dated March 28, 1905.

Application filed January 5,1905- Serial No. 239,817.

To (Ml who/n it Duty concern..-

Be it known that I, GEORGE I MoDoNNELL, a citizen of the United States, residing at St. Louis, Missouri, have invented a certain new and useful Improvement in Electric Lamps, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same,reference being had to the accompanying drawings, forming part of this specification, in which Figure 1 is an elevational view of my improved lamp, and Fig. 2 is an enlarged detail sectional view through the end of the lamp.

This invention relates to a new and useful improvement in electric lamps, the object being to remove the sharp point or teat resulting from the closure of the tubulature.

Heretofore upon closing the tubulature the lamp or bulb was left with a projecting teat, which was not only susceptible to breakage in transportation, but was very brittle and frangible and in addition was objectionable, particularly if it was accidentally struck by a person.

In practicing my invention I prefer to fol' low the method set forth in an application filed by me November 2,, 1904, Serial No. 231,077. Briefly, this method consists in rotating the lamp on a suitable support coincident with the application of heat to the teat, which renders the glass sufficiently plastic to enable the atmospheric pressure to force the teat inwardly, the vacuum inside of the lamp of course causing this, until the bulk of the material which vhad previously formed the teatis located inside of the globe, as shown in Fig. 2. The rotation of the globe when the teat is heated causes the teat in addition to the sinking action to have the appearance of a countersunk button, the rounded portion projecting slightly beyond the peripheral line of the globe. Around this button is a circular cavity, resulting from the method of finishing the lamp.

In the drawings, 1 indicates the lamp, 2 the material which formed the usual external teat, and 3 the button or blunted teat, which has been countersunk and which is surrounded by the cavity above referred to.

\Vhile I have referred to a companion application as illustrating the method and apparatus for producing this article of manufacture, I do not wish my present invention to be confined to the practice of the said method and apparatus, nor do I wish to be understood as limiting my invention to the exact details of construction herein shown and described, as I am aware that minor changes may be made in the same without departing from the nature and principle of my invention.

Having thus described the invention, what is claimed as new, and desired to be secured by Letters Patent, is

1. As a new article of manufacture, an electric-lamp bulb having the material composing the teat located partially within the lamp or bulb; substantially as described.

2. As a new article of manufacture, an electric-lamp bulb havinga sunken, blunted teat; substantially as described.

As a new article of manufacture, an electric-lamp bulb having acircular cavity at one end, in which cavity is located a blunted teat; substantially as described.

4. As a new article of manufacture, an electric-lamp bulb having a sunken, blunted teat with material for strengthening said teat located within the inner peripheral lines of the lamp or bulb; substantially as described.

In testimony whereof I hereunto afiix my signature, in the presence of two witnesses, this 20th day of December, 1904:.

GEORGE P. MoDON N ELL.

itnesses:

LENORE WILsoN, GEORGE BAKEWELL.

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