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Publication numberUS2433982 A
Publication typeGrant
Publication dateJan 6, 1948
Filing dateOct 27, 1944
Priority dateOct 27, 1944
Publication numberUS 2433982 A, US 2433982A, US-A-2433982, US2433982 A, US2433982A
InventorsJr Clarence W Clarkson, Edward J Krok
Original AssigneeJr Clarence W Clarkson, Edward J Krok
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Lamp structure
US 2433982 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Jan. 6, 1948. n y c. w. cLARKsoN, JR., a-r All A 2,433,982


Filed hat. l27. 1944 3 wenrow Clarence d'.CZcbrlnSO-nl,v n #Edward J. l1 rok f u #gk w v l y Cltroz'ueljs Patented Jan. 6, 1948 LAMrsTRUcTURE Clarencew. jClarlrson, Jr.,i Washington, D. C., and-EdwardJ. Krek, Chicago, Ill.

' ApplicationV October 27, 1344, Serial No. 560,612

` 1 This invention relates to lamp structures, and more particularly to those which are used in surgery, although not limited thereto.

Generally stated, surgical lamps are designed to produce on a restricted operating eld a beam of light which is shadowless, intense yet cool, and at the same time color-corrective. In the case of a wound, it is particularly important that besides being cool the restricted beam o'f light be not only shadowless but possess natural color characteristics .as otherwise proper diagnosis is very diiiicult. The proper illuminationv of'rdepth is best obtained lby a light beam derived from multiple sources; and itis therefore most expedient to employ multiple unitsl each of which can be adjusted both physically and optically to train their respective projected light rays upon the focal object.

Numerous prior art lamp structures have sought to attain the foregoing objectives, but, so far as we are aware, they are all possessed of one or more shortcomings, among which are expensiveness to manufacture and maintain, diinculty of operation, and excessive bulk.

It is among the objects of the present invention to provide a comparatively simple and efiicient illuminating apparatus, particularly of the type used in surgery, which projects al light beam of restricted cross-sectional area and which is intense yet cool, practically shadowless, and possessed of substantially natural color.

Another object is the provision of a compact structure of the class described which 'is easilyI portable and vreadily adjustable to project the desired type of light beam in almost any direction.

The invention, then, comprises the features hereinafter fully described, and as particularly pointed out in the claim, the following description and the annexed drawing setting.'v forth in detail a certain lillustrative embodiment of the invention, this being indicative of but one of a number of ways in which the principle of the invention may be employed.

In said drawing:

Figure 1 is a sectional elevation of the lamp structure of Vthe invention.

FigureZ is a fragmentary plan.

Referring more particularly to the drawings, the numeral 2 designates a large conical reflector of standard design, the same being made of either metal or glass in the manner well known in the art. At its inner. or reduced, end the conical reilector 2 is provided with a short annular flange 3 depending froman annular flange 3', which is Y 1 Claim. -(Cl. Z740-1.4:)` y

2 y substantially at right angles to a somewhat longer annular sleeve, and at its outer or enlarged end, the conical reilector is provided with an annular shoulder 23 and a depending side wall 26.

Disposed within the conical reflector 2 is an annular Fresnel lens 5- of standard design`the same being supported in position by means of a series of screws 6 which extend radially inward through the short annular flange 3 and grip the said lens at spaced peripheral points adjacent its inner end.' y

As is well known to those skilled in the art of illumination, a Fresnel lens may be -regarded as a plurality of lenses, the curvature of the back surface of each lzoney being so chosen as to eliminate .spherical aberration. This construction can be modified to distribute light in almost any desired manner. In the embodiment shown, the annular lens 5 has a cylindrical bore and the exterior of the said lens is shaped to provide the Fresnel lens elements, the same being designated at 5a.

Disposed within the annular sleeve 4 is a light bulbA socket I which is supported by an adjusting vmechanism generally indicated at 9. The adjusting mechanism 9 is provided with an operating thumb-screw 9a which "is disposed exteriorly of the annular sleeve 4, the same being operable to adjust the bulb socket 'I longitudinally of the said annular sleeve. The thumbscrew 9a is mounted on the outer end of 4a transversely extending shaft I4 rotatably mounted in bearing members I5 provided on the annular reflector sleeve 4. The shaft I4 has a pinion I'S i mounted thereon adjacent to the inner end of the shaft, which pinion meshes with a rack I I provided on the light socket housing I8, which rack I1 ts into a slot I9 formed in the reector sleeve 4.

The bulb socket 'I carries a light bulb I0 which f projectsinto the annular-Fresnel lens 5. For the purposes of a surgical lamp the light bulb i0 may suitably be any one of a number of concentrated lfilament types, the same as such form ling no part of the present invention.

The outer' end of the annular Fresnel lens 5 is provided with a light-impregnable closure I I which may suitably take the form of a concave- Vconvex cap vprovided with a continuous radially of the adjacent end of the annular lens l, and held in position therein by a series of screwsl2.

According'to the foregoing construction and arrangement each of the light rays emitted by the light bulb l must, in order to be projected from `the outer end of the conical reflector 2, travel through the annular Fresnel lens 5. In this manner, then, the light rays transmitted to the conical reflector 2 are directed by the latter to a point of concentration which is coincident with the axis thereof. In addition, the point of concentration may be varied by the simple expedient of adjusting the longitudinal position of the light bulb .8 withrespect to the annular Fresnel lens 5.

When the light bulb is raised by means of the adjusting mechanism 9 the light rays passing through the lens 1 are bent down and are concentrated at a lower point than was the case prior to said adiustment, but on the same axis. When the light bulb vIl! is lowered, the converse is true (i. e. the light beams concentrate at a higher point out on the same axis as aforesaid). Whatever the degree of adjustment, the reflected light beam is in effect the same as.derived from multiple sources because of the optical effect of the combined annular Fresnel lens and the conical reflector 2. Thus, the projected light beam is inherently shadowless.

The outer end of the conical reflector 2 is provided with a conventional heat-absorbing and color-corrective glass I3 which is suitably removably maintained in position by spring clips 20 mounted in an annular closure member 22 for the outer or enlarged end of the conical reflector, the closure member 22 being connected hingedly on the side wall 26 of the reector by the hinge 25. The closure member 22, when in closing position,abuts against the annular shoulder 23 on the reflector 2 and is held removably in position by screw 24 threadedly mounted in the side wall 26 and contacting the closure member 22 at its inner end in diametrically opposite relation to the hinge 25. Upon loosening the screw 24, the closure member 22 may be swung open about its hinge 25 for replacing or cleaning the parts of the lamp structure. The effect of the glass I3 is to intercept the light rays projected by the con-l ical reiiector and remove therefrom the heat-giving infra-red rays and also any color characteristics, whereby the proiected beam of light is rendered cool and colorless.

Other modes of applying the principles of the invention may be employed, changes being made as regardsthe details described, providing the features stated in the following claim, or the equivalent of such, be employed. l

Having thus described our invention, what we claim as new and wish to secure by Letters Patent is:

A lamp structure comprising a reiiector housing havin-g a cylindrical sleeve portion and a conical reflector portion, a cylindrical housing adjustably mounted in the sleeve; an annular flange extending from the sleeve portion at substantially right angles thereto, and a second flange depending substantially perpendicularly therefrom, the conical reflector portion extending divergingly from the second ange, means for slidably adjusting the housing in the sleeve, a light socket mounted in the housing, a lamp mounted in the socket, a tubular Fresnel lens enclosing the lamp, a series of screws threadedly mounted in the second flange and extending therethrough in engagement with the Fresnel lens for holding the lens in position, an opaque cap closing the lens, means for securing the cap to the lens, the said conical reiiector portion terminating in an annular shoulder having a flange depending therefrom to form an annular wall, an annular closure member for the conical reflector positioned in the wall, a heat-absorbing and col- 'or-corrective glass removably mounted in the arinular closure member for closing the annulus thereof, a connection between the annular closure member and the wall, and a securing screw threadedly mounted in the wall and extending therethrough in engagement with the annular closure member in diametrically opposite relation to the said connection for holding the closure member in closing position against the shoulder `for closing the conical reiiector portion.


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

UNITED STATES PATENTS Great Britain Jan. 8, 1942

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1806384 *Apr 19, 1928May 19, 1931Anciens Ets BarbierShadowless lighting apparatus
US1985922 *Oct 17, 1931Jan 1, 1935Gelb JosephOperating table illuminator
US2173325 *Feb 24, 1936Sep 19, 1939American Sterilizer CoSurgical operating luminaire
GB542417A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2536533 *May 13, 1946Jan 2, 1951Bank Citizens National Trust SDirectional-beam lighting unit
US2831104 *Jan 30, 1956Apr 15, 1958Brandt Robert JayPhotographic illuminating means
US2896066 *Jun 10, 1957Jul 21, 1959Quetin EmmanuelLighting apparatus for dental surgeries
US3103156 *Mar 30, 1961Sep 10, 1963Emerson Electric Mfg CompanyArea lighting and air exchange apparatus
US3786244 *Oct 2, 1972Jan 15, 1974Physical Syst IncSurgical lamp
US4037096 *Aug 9, 1974Jul 19, 1977American Sterilizer CompanyIlluminator apparatus using optical reflective methods
US4604679 *Mar 6, 1985Aug 5, 1986Carello Industriale, S.P.A.Method of assembling a motor vehicle headlight, and headlight produced using such a method
U.S. Classification362/277
International ClassificationF21S8/00
Cooperative ClassificationF21W2131/205