US1817975A

US1817975A - Electric lamp

Info

Publication number: US1817975A
Application number: US401723A
Authority: US
Inventors: Harry A Douglas
Original assignee: Individual
Current assignee: Individual
Priority date: 1929-10-23
Filing date: 1929-10-23
Publication date: 1931-08-11
Anticipated expiration: 1948-08-11

Description

g- 11, 1931- H. A. DOUGLAS 1,817,975

ELECTRIC LAMP Filed Oct. 23, 1929 2 Sheets-Sheet l fig Aug. 11, 1931. H, A. DOUGLAS ELECTRIC LAMP Filed Oct. 23, 1929 2 Sheets-Sheet 2 Patented Aug. 11, 1931 UNITED STATES PATENT OFFICE ELECTRIC LAMP Application filed October 23, 1929. Serial No. 401,723.

My invention relates to lamp structures employing sockets for receiving the bases of incandescent lamps. The invention has for its object the provision of improved means for fixing the lamps in predetermined ositions with respect to the sockets receiving the bases of the lamps. The invention finds an important use in connection with )lamps having concave reflectors that are m equipped with holders for the sockets and having in association therewith means for predetermining the positions of the sockets with respect to the holders and reflectors. A lamp thus constructed will direct light in a fixed path with respect to the axis of the reflector, thereby avoiding difliculty now frequently encountered in the adaptation of reflecting lamps to automotive vehicles, bodily or other adjustment of the lamps having frequently been required when the users happen to find that the light is improperly directed.

In my copending application Serial No. 403,613 filed October 30, 1929 (Case 256),

I have broadly claimed a lamp receiving. socket within a holder and smaller in cross section than the holder, and means pressing the socket laterally against one side of the holder. The structure disclosed in the g aforesaid copending application employs a concave reflector with respect to which the socket holder is fixed, the bore of the socket holder being in register with an opening that is formed through the reflector to permit of the insertion of the base of an incandescent lamp. The structure of the aforesaid application is also inclusive of spaced apart spacing means intervening between the holder and socket in the place at which the socket is pressed against the holder.

The structure herein disclosed is preferably inclusive of all of the characteristics above generally set forth. A portion of the structure involving my present invention is inclusive of an incandescent lamp having its base received in said socket and which base is smaller in cross section than the bore of the socket, and a spreader interposed be tween adjacent side portions of the lamp base and socket to force the lamp base against a side of the socket. My structure preferably fixes the location of the filament with respect to the reflector. By fixin the position of the lamp longitudinally o the socket the necessity of a special design for the reflector which has hitherto been roposed to procure the same lighting e ect of the filament in different positions along the reflector axis is avoided. The invention, however, is not to be thus limited.

If the holder be associated with a reflector, the position of the lamp filament with respect to the reflector is assured, it being understood that the lamp filaments of the incandescent lamps which are to be used in the structure of my invention preferably occupy predetermined uniform positions with respect to the lamp bases. To further assure the precise positions of the lamps, I desirably provide V-shaped seats in the bayonet slots that receive the ba onet pins upon the lamps, so that the lamps are brought to a uniform position rotatively.

The invention will be more fully explained in connection with the accompanying drawings, showing the preferred embodiment thereof, and in which Fig. 1 is a plan View with a portion of the reflector shown in section; Fig. 2 is a View from beneath, part of the bulb being broken away; Fig. 3 is a; sectional view on line 3-3 of Fig. 1; Fig. 4 is a sectional view on line H of Fig. 3. Fig. 5 is a sectional View on line 55 of Fig. 3; Fig. 6 is a sectional ,view on line 66 of Fig. 3; Fig. 7 is a perspective view illustrating component parts of the structure in separated relation; and Fig. 8 is a sectional elevation taken through the axis of the parabolic reflector.

The lamp illustrated includes a housing or back element 1 having a bracket 2 on its bottom side by which it may be assembled with the automotive vehicle or other support, as indicated. The housing or back 1 encloses a parabolic reflector 3 which is formed with a grooved flange 4 at its forward end. This flange is pressed against a rim 5, provided upon the housing, by an assembling ring 6. This assembling ring also presses the light transmitting closure 7, usually of glass, againsta gasket 8 which is seated in the flange 4.

The generally cylindrical socket holder 9 has its forward end passed through a circular ening formed through the crown of the re ector, in the embodiment of the invention shown. The forward end of the holder 9 is formed with

flanges

10 and 11 between which the surrounding edge portion of the reflector is clamped, whereby the holder and reflector are maintained coaxial, in the structure illustrated.

The generally cylindrical lamp socket 12 is held in assembly with and within the holder 9 b the means hereinafter set forth. This soc et is preferably formed with a single bayonet slot or channel 13 for receiving a bayonet projection 14 upon the base 15 of an incandescent lamp. This bayonet projection is maintained in a V-shaped retaining seat 13 of the bayonet slot by any suitable means, the V-shaped seat holding the lamp from rotative movement. The means illustrated is inclusive of a coiled spring 16 which surrounds a plunger 17 constituting a circuit terminal and presses forwardly upon the plunger head 18 and rearwardly upon the flan e 19 of a metallic guiding sleeve 20. This guiding sleeve is mounted upon an insulating disc 21 which is fixedly assembled with and within the rear end of the socket 12. The plunger head 18 presses against a contact 22 which is carried by the generally cylindrical lamp base 15 which is made of insulating material.

The lamp structure illustrated is a so-called single pole structure, though the invention is not to be thus limited. Where a single pole structure is employed, the contact 22 is upon the axis of the lamp base. A stiff leading in wire 24 establishes connection between the contact 22 and one terminal of the filament 25. Another stiff leading in wire 26 establishes a connection between the other terminal of the filament and the metallic sheath 27 which surrounds the insulating portion of the lamp base and, from the point of view of my invention, also constitutes a p: rt or enlar ement of the lamp base. The body of the re ector, the holder 9, and

'the socket 12 are grounded and when the lamp is in place the sheath 27 is also grounded as it has connection with the holder, as will more fully appear.

In carrying out my invention the cross section of the socket 12 is smaller than the bore of the holder 9 and the base of the lamp, inclusive of its sheath 27, is smaller, in cross section, than the bore of the socket.

Spaced apart spacing means intervene between the holder 9 and the socket 12. These spacing means are preferably in the form of ribs 28 which extend longitudinally of the holder and socket. Each rib is desirably integrally formed with one of the elements 9 or 12, both ribs being shown as being integrally formed with the holder. The ribs are spaced less than 180 degrees apart, preferably 120 degrees apart. The means for pressing the socket 12 against the holder 9 is desirably inclusive of two spring tongues 29 which are integrally formed with the holder 9. The socket 12 is formed with a lug 30 which is snugly engaged between re cessed portions of the spring tongues 29 and having an extension 30' engaging the rear wall 9' of a slot 9 that is formed in the holder to fix the socket with respect to the holder. This slot also serves to form the spring tongues.

The spreader employed for positioning the lamp base within and with respect to the lamp socket is desirably inclusive of the aforesaid lug 30 whose inner face is a wedging face that takes part in the spreading action. The spreader is also inclusive of a plunger 31 having one end entered between the lug 30 and the base of the lamp. A spring 32 surrounds the shank of the plunger. This spring is bottomed, at one end, upon the disc 21 and is coupled, at its other end, with a forward portion of the plunger. The spring is under compression and exerts forward movement upon the plunger which passes through and is in sliding engagement with said disc. The plunger has a hook end 31 by which the extent to which it is forwardly pressed is limited when the lamp is moved from the socket. The plunger serves to press the lamp base against a side of the socket that i" opposite the lug 30. Spaced apart distance preserving means are interposed between the lam socket and the lamp base where the base is pressed toward the socket. This distance preserving means is preferably in the form of two ribs 33 which are less than 180 degrees apart, preferably 120 degrees apart. Each rib is preferably integrally formed with one of the

elements

12 or 27. In the embodiment of the invention shown both ribs are integrally formed with the sheath 27. By the structure illustrated, identically constructed lamps having their filaments in exactly the same positions with respect to the lamp bases may be interchangeably assembled with the lamp sockets with the assurance that the filments will occupy one predetermined location with respect to the reflector axes.

While the lamp and socket assembly herein disclosed is preferably used in connection with a lamp structure that includes a concave reflector, the invention is not to be thus limited.

Changes may be made without departing from the invention.

Having thus described my invention, I claim:

of an incandescent lamp havin 1. The combination w1th a lamp socket; of an-incadescent lamp having its base received in said socket and which base is smaller in cross section than the bore of the socket; and a spring pressed wedging element interposed between adjacent side portions of the lamp base and socket to force the lamp base against a side of the socket.

2. The structure of claim 1 wherein there are spaced apart spacing means between the socket and lamp base where the lamp base is pressed toward the socket.

3. The structure of claim 1 wherein spaced apart spacing ribs extending longitudinally of the socket and lamp base in tervene between the socket and lamp base where the lamp base is pressed toward the socket.

4. The combination with a lamp socket; of an incandescent lamp having its base received in said socket and which base is smaller in cross section than the bore of the socket; and a spreader interposed between adjacent side portions of the lamp base and socket to force the lamp base against 'a side of the socket, said spreader being inclusive of a wedging element interposed between side portions of the socket and base and a spring which presses said wedging element into spreading engagement with the socket and lamp base.

5. The structure of claim 4 wherein there are spaced apart spacing means between the socket and lamp base where the lamp base is pressed toward the socket.

6. The structure of claim 4 wherein spaced apart spacing ribs extending longitudinally of the socket and lamp base intervene between the socket and lamp base where the lamp base is ressed toward the socket.

7. The com ination with a lamp socket;

its base received in said socket and which ase is smaller in cross section than the bore of the socket; and a spreader interposed between adjacent side portions of the lamp base and socket to force the lamp base a alnst a side of the socket, said spreader being inclusive of a wedgingelement interposed between side portions of the socket and base and a spring which is carried by the socket and presses said wedging element into spreading engagelllnent with the socket and lamp base.

8. e structure of claim 7 wherein there are spaced apart spacing means between the socket and lam base where the lamp base is pressed towar the socket.

9. The structure of claim 7 wherein spaced apart spacing ribs extending longitudinally o the socket and lamp base intervene between the socket and lamp base where the lamp base is pressed toward the socket.

10. The combination with a lamp socket; of an incandescent lam havin its base received in said socket an which ase is smaller in cross section than the bore of the socket; and a spreader interposed between adjacent side portions of the lamp base and socket to force the lamp base against a side of the socket, said spreader being inclusive of a wedging element interposed between side portions of the socket and base and a spring which presses said wedgin element into spreading engagement with t e socket and lamp base, the socket having a cam portion which is the part of the socket with which the wedging element has engagement.

11. 'The structure of claim 10 wherein there are spaced apart spacing means between the socket and lamp base where the lamp base is pressed toward the socket.

12. The structure of claim 10 wherein spaced apart spacing ribs extending longitudinally of the socket and lamp base intervene between the socket and lamp base where the lamp base is pressed toward the socket.

13. The combination with a lamp socket; of an incandescent lamp having its base received in said socket and which base is smaller in cross section than the bore of the socket; and a spreader interposed between adjacent side portions of the lamp base and socket to force the lamp base against a side of the socket, said spreader being inclusive of a wedging element interposed between side portions of the socket and base and a spring which is carried by the socket and presses said wedging element into spreading engagement with the socket and lamp base, the socket having a cam portion which is the .part of the socket with which the wedging element has engagement.

14. The structure of claim 13 wherein there are spaced apart spacing means between the socket and lamp base where the lamp base is pressed toward the socket.

15. The structure of claim 13 wherein spaced apart spacin ribs extending longitudinally of the s05; tervene between the socket and lamp base where the lamp base is pressed toward the socket.

In witness whereof, I hereunto subscribe my name.

HARRY A. DOUGLAS.

et. and lamp base in-