US493341A

US493341A - John h

Info

Publication number: US493341A
Authority: US
Publication date: 1893-03-14
Anticipated expiration: 1910-03-14

Description

(No Model.)

J. H. PURDY.

LAMP.

No. 498,341. Patented Mar. 14, 1893.

UNITED STATES PATENT OFFICE.

JOHN H. PURDY, OF CHICAGO, ILLINOIS.

LAMP.

SPECIFICATION forming part of Letters Patent No. 493,341, dated March 14, 1893. Application filed September 12, 1892. $erial No. 445,672. (No model.)

To all whom it may concern:

Be it known that I, JOHN H. PURDY, of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Lamps, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part of this specification, in which Figure'l. is a side view of a lamp embodying the features of my invention,the base being shown in section, and Fig. 2. is a central vertical sectional view of the lamp and base, said lamp being shown in the position ordinarily occupied when in use.

Corresponding letters of reference in the different figures indicate like parts.

My invention relates to spherical lamps more especially adapted for jewelers use, and consists of an improvement upon Letters-Patent No. 232,206, issued to me on the 14th day of September, 1880. In said Letters-Patent I have described and shown a lamp, the body of which is spherical in form and arranged to rest loosely in a cup-shaped base,the object of this construction being to tilt the lamp to any desired angle; but, as there is nothing in said construction to serve as a counter-poise for the Wick-tube, great difficulty has been heretofore experienced in keeping the same in position when placed at a given angle. Roughened leather, rubber, sand, pumicestone and other things have been placed in the cup-shaped base to form a friction-surface, but with only partial success. The jar upon the work table upon which the lamp is placed caused by pounding or otherwise, sooner or later causes the lamp tube to fall to a horizontal position in spite of the utmost precaution, thereby changing the uniform character of the flame and enabling the alcohol to be wasted.

"The object of my invention is to overcome this objection; and to so construct the body of a spherical lamp that it may retain its position at whatever angle the wick tube may be tilted;-all of which is hereinafter more particularly described and claimed.

Referring to the drawings, A represents the body of the lamp which is spherical in form and is adapted to rest loosely in the cup shaped base B. The wick tube 0 is made of metal in the usual manner.. The body A is preferably formed from glass or other vitreous material, and is so blown or molded that that portion D diametrically opposite the wicktube is thicker than elsewhere. I prefer to gradually reduce the thickness of said body from the part which forms the bottom when the tube is upright. I have shown said reduction as terminating at the top of the lamp; but it is obvious that it may be at any intermediate point. As shown, the curve of the interior is made eccentricto the outer circumference. I have found in actual practice,that the lamp as thus constructed, may be tilted in any desired position and will retain said position indefinitely without being affected by jar or other movement.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is-

1. The combination in a lamp of a cup shaped base, a spherical lamp body loosely mounted therein, and a wick tube, the walls of said lamp body being made thicker at the bottom or opposite the wick tube, substantially as shown and described.

2. A spherical lamp body, the surface of the interior of which is eccentric to that of the exterior,in combination with a wick tube and cup shaped base, substantially as shown and described.

In testimony whereof I have signed this specification, in the presence of two subscribing witnesses, this 1st day of December, 1891.

JOHN H. PURDY.

WVitnesses:

D. H. FLETCHER, J. B. HALPENNY.