US1580311A

US1580311A - Headlight

Info

Publication number: US1580311A
Application number: US653512A
Authority: US
Inventors: John M B Lewis
Original assignee: Individual
Current assignee: Individual
Priority date: 1923-07-24
Filing date: 1923-07-24
Publication date: 1926-04-13
Anticipated expiration: 1943-04-13

Description

April 13 1926. I

J. M. B. LEWIS HEADLIGHT Filed July 24. 1923 2 Sheets-Sheet 1 Humm gnomi Voz April 13 1926.

J'. M. B. LEWIS HEADLIGHT Filed July 24. 1923 `2 Sheets-Sheet 2 Cucina Patented Apr. 13, 1926.

TED

PAENT nnannren'r. y

Application lea July 24, 1923. Serial No. 653,512.

To aZZ whom t may concern:

Be it known that I, JOHN M. B. Lnwis, a citizen of the United States, residing at Lynchburg, in the county of Campbell and t State of Virginia, have invented cert-ain new and useful Improvements' in Headlights, of which the following is a specification.

rThis invention relates to headlights and more particularly to headlights for automobiles, the arrangement of the various elements in the light being of a novel character whereby the usual glare in the eyes of approaching drivers is positivelyprevented.

It is an important object of the present invention to provide a headlight structure wherein the height of the uppermost ray of the light beam will at all times be below the legal height regardless of the adjustment of the light source. f

A. further object is the provision of means for adjusting the light source to secure proper focusing without bringing the machine upon which the lights are mounted, to a regular testing station.

Other obfects and advantagesof the` invention Will be apparent during the course of the following description.

In a copending application filed November 3, 1922, Serial No. 598,7 93,1 have disclosed a headlight construction wherein a light source isA mounted within a reflector which is adapted to reflect rays of light upon a second reflector arranged in the upper part of the casing, the rays from the second relector passing outwardly through the light 'opening inthe forward part of the casing. I have foundfthat the use of an elliptical reflector in place of the reflector shown in the above mention application permits of more accurate cont-rol of the light rays while with the present construction a materially larger main reflector may be employed.

The present application is an improvement over the above mentioned application andI also my copending application Serial No. 652,442 filed July 18, 1923.

Inthe drawings, I have shown several embodiments of the invention. In this Showing, 'l

Figure 1 is a central vertical longitudinal sectional view through a headlight embodying the present invention. i

Figure 2 is a adjustable reflector and associated elements.

detail perspective of theV Figure 3 is a vertical longitudinalfsec-l Y tional view through a modied form of re- Hector.

Figure 4 is a section taken on. line 4-4 of Figure 3, f `Figure 5 is a front elevation of the headlight, v

Figure 6 is a section taken on ,line 6--6 of Figure 1, and,

Figure 7 is a fragmentary perspective 'of the smaller end of the elliptical reflector and associated elements.

Referring to the drawings, the numeral 10 designates a casing as a whole, split as at 11 to provide upper and

lower sections

12 and 13. The upper section 12 may be provided with an outwardly off-set depending flange 14 surrounding 'the upper edge of the lower casing section as clearly shown. f Suitable vmeans is provided for supporting kthe casing upon the automobile. In the drawings, I have shown a bracket 15 riveted as at 16 or otherwise secured beneath the casing and provided with a depending tubular member 17 to receive a support 18 as shown in Figure 5.

The forward end of the casing is provided with alight opening 19 in which is mounted preferably a plain glass 20 held in position by an apertured plate 21 as will be clearly understood. p

An elliptical reflector 22 is mounted vin the rear of the casing and is provided upon its smaller end with a tubular section 23 having a slot 24 therein as shown in Figure 7, for a purpose to .be described. A bracket 25 is secured within the lower casing section by rivets 26 or the like and this bracket is provided with a portion 27 surrounding the tubular extension 23 but having its rear end slightly spaced from the rear end ofthe tubular member 23. A sleeve 28 has its forward end mounted within the opening in the extension 23 and is provided upon one side with the usual bayonet slot (not shown) for the reception of a pin 29 carried by the 100 basey 30 of an electric light bulbl 31. The sleeve 28 1s provided with a spring Contactl 32 adapted to contact with the base contact of the light bulb as will be obvious. The' sleeve 28 is provided with a pin 33 which 105 is adapted to be received within the slot 24 of the tubular extension 23. l The sleeve 28 is provided upon its outer -surface and near its rear end with teeth 34 adapted to engage the threads of a screw 35 rotatably 110 mounted within the rear of the casing and adapted to be rotated by a suitable knob 40. One end of the shaft 39 extends beyond the casing and is provided with a depending portion 41 pivotally connected with the forward end of an operating rod 42. The rear end of the rod 42 is adapted to be conveniently located near the seat of the driver in order that it may be readily operated. A coil spring 43 is mounted between the rear end of the reflector 37 and the upper wall ofthe casing section 12 as shown in Figure 1. The spring 43 is of the compression type and is fairly heavy so as not to be affected by the jolts and vibrations to which the automobile is subjected while traveling. A stop bracket 44 is secured to the upper wall of the casing section 12 above the forward end of the reflector 37. It will be obvious that 4the spring 43 will urge the rear end of the reflector downwardly, movement of the latter being limited by the stop 44. The reflector 37 is so arranged within the casing that the center of its lower or reflecting face will be arranged adjacent the focal point of rays of light from the' elliptical reflector 22. It will be obvious that light rays cast by the reector 22 will be reflected downwardly and outwardly by the reflector 37 through the light opening 19. Since the reflector 37 is -arranged wholly above the level of the light opening 19 itiwill be obvious that it will be screened from the view of drivers of vehicles approaching in the opposite direction.

A screen 45 is arranged within the lower casing section as shown in Figures 1 and 6 and this screen is arranged with its upper edge slightly spaced from the reecting face of the reflector 37. Inasmuch as the screen 45 is arranged almost directly beneath the focal point of the rays from the elliptical reliector it will be obvious that the upper edge of the screen may be arranged in close proximity to the reflector 37 without interfering in any way with the light rays passing to or from this reflector. 45 is adapted to be supported in position by brackets 46 secured in any suitable manner within the lower casing section 13.

Means are provided for determining the proper focusing of the bulb 31 within the elliptical reflector 22. In the drawings, I have shown a disk 47 pivotally mounted as at 48 upon one side of the screen 45, to

The screen` swing in a vertical plane. As is well known an elliptical reflector with a light source arranged at its principal focus will reflect light rays which converge substantially to a pointmat the conjugate focus of the reflector. I prefer to employ an elliptical re- Hector whose conjugate focus is in the same vertlcal plane yas the rear face of the disk -47, for a purpose to be described. Ob-

headlight will form a resulting beam which will be substantially .five feet in depth and extend not over four feet from the surface of the road. It is similarly required that the light beams from the two headlights of an automobile must spread to a widthof substantially twenty feet at a distance of seventy feet from the front ofthe vehicle. v In Figures 3 and 4 of the drawings, I have shown a Jsomewhat modified form of reflector which may be substituted for the reflector 37 in the States having the more rigid regulations as to light distribution. Asp,

shown, I provide a reflector 49 rigidly connected to the cross shaft 39 so as to be operated in the same manner as the reflector v37 previously described. Vhen the reflector 49 is employed the lower or reflecting surface thereof is preferably arranged slightlv below the focal point of the light rays from the reflector 22 in order that the beam cast upon this reliector will vcover a substantial arean As shown in Figure 3. the reflecting surface of the reflector 49 is convex longitudinally but is concave transversely as shown in Figure 4. When the reflector 49 is employed it will be seen that the upper rays '50 from the reflector 22 will be intercepted substantially to the rear of the reflector 49 in such a manner that the resulting ray 51 will pass downwardly at a slight angle throughy the glass 20. The lower rays 52 will be intercepted by the forward portion of the reflector 49, the resulting rays 53 also passing outwardly through the glass 20. The rays 51 and 53 designating the lowermost and uppermost rays from the casing diverge only sufficiently to cast a beam of substantially live feet in depth as above described. The reflector 49`is formed with its reflecting surface concave transversely as previously described so that the rays reected therefrom will be confined within such an angle that the resultin beam will b e substantially twenty feet 1n width at a distance of seventy feet in front of the vehicle.

The operation of the device is as follows:

When a bulb is inserted within the reflector 22 the upper casing section is first removed.l The light bulb is inserted in the usual manner and the knob 36 may be revolved to move the filament of the light forwardly or rearwardly until the propel' focus is reached. Rotation of the sleeve 28 is prevented by engagement of the pin 33 within the slot 24. The proper focusing of the light may be determined by removing the upper casing section 12 and swinging the disk 47 to t-he dotted line position, shown in Figure 6, whereby a point on the rear face `of the disk will coincide with the conjugate focal point of rays from the elliptical reflector. The bulb then may be moved forwardly or rearwardly until the smallest possible spot of light is obtained on the disk 47. Thus it will be apparent that adjustment-of the light and the determination of the proper focus thereof may be had without resorting Ato any special testing apparatus. It will be obvious that when the device is in use the light source 31 and

reflectors

22 and 37 will be wholly'screened from view from a point in front of the vehicle and above the upper limit of the light opening 19, when the vehicle is traveling upon a level street 0r road. `When the vehicle is traveling up a hill andv is approaching the top thereof, the driver of the vehicle, by moving the rod 42 rearwardly, may tilt the forward end of the reflector 37 downwardly to throw the rays of light on the road close to the vehicle in order that they may not be thrown into the eyes of drivers of approaching vehicles.

It is to be undetood that the form of my invention herewith shown and described is to be taken as a preferred example of the same, and that variogus changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention or `the scope of the subjoined claims.

Havin described my invention, I claim:

1. A eviee of the character described comprising a casing having a light opening therein, van elliptical reflector mounted in said casing, said reflector and the conjugate focus thereof being arranged on opposite s1des of a horizontal plane passlng t lrough said light opening, a light source mounted in -said reflector, and a second reflector arranged between said elliptical reflector and said light opening, said second named reflector being arranged with its reflecting surface near the focal point of light rays from therein, an elliptical reflector ranged with its reflecting surface near the focal point of light rays from said elliptical reflector, and a focusing member mounted within said casing and movable to intersect the axis of said elliptical reflector at its focusing point when said second named reflector is removed.

4. A device of the character described comprising a casing having a light opening mounted lin said casing, a light source mount-ed in said reflector, a movable reflector arranged between said elliptical reflector and said light opening. said second named reflector being arranged with its reflecting surface near the focal point of light rays from said elliptical reflector, a screen arranged with its edge slightly spaced from said second nalned reflector and near the focal point of light rays from said elliptical reflector, and a focusing member carried by said screen and movable to intersect the axis of said elliptical reflector at its focusing point when said second named reflector is removed.

' 5. A device of the character described comprising a casing having a light opening therein, an elliptical reflector mounted in said casing,la light source mounted in said reflector, means operable from without said easing for adjusting said light axially of said elliptical reflector, a second reflector arranged between said ellipticall reflector and said light opening, and means adapted to be arranged at the focusing point of light vrays from Isaid elliptical reflector for determining the proper focus of said light source. A6. A headlight including a casing, means for projecting a light beam which converges substantially to a focal point within said casv ing, an opaque member normally arranged wholl outside the path of travel of the light am and adapted to be moved wholly across the normal path of the beam at its focal point to determine the proper focus of said light projecting means, and means for focusing said light pro'ecting means.

In testimony whereof affix my signature.

JOHN M. B. LEWIS.