US153341A - Improvement in reflectors - Google Patents

Description

UNITED STATES PATENT OFFICEo CHARLES E. JAooBsEN, vor NEW YORK, N. Y.

IMPROVEMENT IN REFLECTORS.

Speciiication forming part of Letters Patent No. 153,341, dated Juy 21, 187A; appli. aiion filed July 9, 1874.

To all whom it may concern:

Be itknown that I, CHARLES F. JACOBSEN, of the city, county, and State of New York, have invented certain new and useful Improvements in Iteflectors, particularly such as vare termed head-lights or locomotive-reiiectors,77 of which the following is a specification:

It is well known that nearly all concave reiiectors, whether parabolic or of other shape, are made of metal, polished, and silver-plated. This plating is constantly liable to tarnish, and requires to he continually cleaned. which rapidly wears it away and requires it to be renewed. Such reflectors are, therefore7 very expensive.

To overcome this difficulty attempts have been made to form reflectors of glass, blown in one piece, silvered, and fitted within a metallic casing; but it is not possible to make such glass true in all respects, and therefore the desired effect is lost. Moreover, the operation of forming the glass is expensive, the glass is very apt to become dulled in the operation, and a fracture of one part ruins the whole. Attempts have also been made to construct reilectors with a retlectingsurface cornposed of small pieces of glass, put together within a metal casing; but such reflectors, owing to the numerous angles formed, give but little light as comparedwith reiiectors having a true curve.

To remedy the defects of reflectors such as heretofore used, and to produce an article which, while adapted to obtain the best possible effect, is yet cheap and durable, I form the reiiecting-surface of glass, curved to conform with the shape desired for the reiiecting-surface, and made in independent sections, any one of which can be removed without disturbing the others. The sections are curved lon- `s ritudinally and transversely, and t ltogether accurately within their casing, so that, to all intents and purposes, a true reflecting-surface is obtained that will reiiect the light as well as the most perfect reiiector heretofore used.

rIhe manner in which my invention is or may be carried into effect will be readily understood by reference to the accompanying drawing, in which` Figure l is a front elevation, and Fig. 2 is a longitudinal central section, of a reflector made in accordance with my invention.

A A are the glass sections, (in this instance four in number,) each extending in continuous length from front to rear of the reiiector. They may be made of either plain or corrugated glass, silvered on the back. In this instance they are corrugated. Each section is curved longitudinally and transversely to the proper extent, so that, when put together, they will furnish a true and practically unbroken reflecting-surface of the shape desired, wh ether parabolic or other conformation. The reiiector in the drawing is a parabolic reiector.

The sections are formed from plain or plate glass, or other suitable glass. After being cut from the glass sheet, they are brought to the desired form by being laid on a mold of proper shape and heated in a mufiie or furnace until softened to that extent when they will drop into and take the shape of the mold. This is one convenient way in which they may be most accurately shaped. After shaping, they are silvered on the rear side, and are then fitted together within the metal casing, forminga true reiecting-suriace, as shown in the drawing.

The metallic casing is shown at B. It is provided at the front with a lip or, ange, a, or equivalent device, under which the front edges of the sections are placed. The sections at the rear are preferably held in place by a center plate or button, b, which overlaps the converging ends of all the sections, holding them firmly in place. It is itself held in position by a screw or pin, c, passing through it into the metal casing behind. By removing this center plate or button any one of the sections can readily be slipped out from the cas- 'ing at any time without disturbing the other sections. An aperture is formed at the bottom ofthe reiiector for the passage of the gasburner stem or pipe, and another aperture is formed in the top, just over the chimney of the burner. rIhese apertures, formed through both glass surface and metal casing, may be surrounded by a metallic binding, d, which is of sheet metal, readily removable whenever desired, an d serving, when in place, to afford additional security to the glass sectional lining.

It will be understood that my invention,

Within which they are fitted side by side, and formed and arranged so that the lines of section radiate from the apex of the reecting surface, as shown and set forth.

3. The combination ofthe metallic casing and curved glass sections with the removable center button or holding-plate overlapping the converging ends of the sections, substantially as shown and set forth.

In testim onywhereof I have hereunto signed my name this 26th day of June, A. D. 1874.

CHAS. F. JAUOBSEN. Witnesses: i

EWELL A. DICK, HENRY R. ELLIOTT.

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