US2137174A - Tubular lamp base and socket - Google Patents

Description

Nov. 15, 1938. A. J. MARSHAUS TUBULAR LAMP BASE AND SOCKET .Filed March 25. 1938 59 Inventor: 3y Anthohg J. Mar-shaus,

H s Attorneg.

Patented Nov. 15, 1938 UNITED STATES- mm Lamp Base Ann socxa'r Marshaus, East Cleveland, Ohio, assignor to General Electric Company, a corpo- Anthony J.

ration of New York REISSUED AUG 2 7 1940 App ication March 25, 1938, Serial No. 198,058

a 10 Claims.

My invention relates to electric lamps and similar devices, and more particularly to a base and socket construction for such devices. Still more particularly, my invention relates to a base and socket construction for electric lamps of the double-ended discharge type, in which a filamentary electrode is mounted at each end of the lamp. v

One object of my invention is to provide a base and socket construction for electric lamps wherein the lamp may be readily inserted in its socket and positively locked therein so as to eifectively prevent unwarranted or premature disengagement therebetween.

Another object of my invention is to provide an electric lamp socket in which the contact terminals are entirely concealed and unexposed so that the danger of shock or of short circuits is absent. 7

Still another object of my invention is to provide a base and socket construction for electric lamps wherein the lamp may be freely rotated in its socket, thereby eliminating the possibility of the base contact prongs being broken off the base, or the cement bond between the base and the glass envelope of the lamp being disrupted during insertion in or removal of the lamp from its socket.

A further object of my invention is to provide a lamp base construction which will insure the correct assembly of the lamp in its socket, thereby eliminating the possibility of any binding or Jamming oi the base in the socket during insertion of the lamp in such socket.

A still further object of my invention is to provide a socket and base construction for electric lamps in which the base is provided with a plurality of pins or prongs arranged in a common plane, and the socket is provided with a circular slot and a diametrical slot with leaf springs disposed in said circular slot on opposite sides of said diametrical slot, whereby the lamp base prongs may be inserted in said dlametrical slot'and the lamp then rotated to bring certain of said prongs into interlocking engagement with the leaf springs.

Further objects and advantages oi. my invention will appear from the following detailed description of a species thereof and from the accompanying drawing.

In the drawing, Fig. 1 is a side view, partly in section, of a base and socket construction comprising my invention, the base being mounted on a lamp disposed in correct position preparatory to its insertion in the socket; Fig. 2 is an isometric view of the socket shown in Fig. 1 with the cover plate removed and shown separate therefrom: Fig. 3 is an end view, partly in section, of the inner or lamp-engaging end of the socket shown in Fig. 1; Fig. '4 is a detailed view of the cover plate for the socket shown in Fig. l;-

Referring to the drawing, the socket l0 according to my invention comprises a base or body member ii, a pair of spring fingers or contact members i2, i2, and a cover plate i3. The base and cover plate members ii and i3 respectively are made of suitable insulating material, preferably that commercially known as Bakelite. The inner or lamp-engaging side it of the base member is hollowed out adjacent its front wall it to provide a circular slot l8 forming a cylindrical stud i1, and a diametrical slot i8 extending rearwardly from the front wall it back through the cylindrical stud ll. The inner side i4 ofthe base member is further hollowed out rearwardly of the circular slot i6 to provide a channel IS in substantial alignment'with the said diametrical slot is and extending rearwardly from the circular slot it to the back of the base member. To provide clearance for flexing of the spring contact members i2, the walls 20 of the channel l9 diverge forwardly. At its rearmost extremity the channel is is widened or enlarged, as indicated at M, to thereby provide suitable abutment shoulders 22, 22 for the spring contact members i2, i2. These abutment shoulders preferably extend at approximately right angles to the longitudinal axis of the channel IS. The base member'is provided at its rear with a pair of oppositely extending projections 23, 23 having: openings 24 through which socket mounting screws are adapted to extend.

Mounted within thehollowed-out portions i6 and IQ of the base members are the plate spring elements i2, i2 previously referred to, said spring elements constituting the terminal or contact members of the socket. These contact members are preferably made of full-spring phosphorbronze, and are bent laterally at their rear extrmities to provide mountinglugs 25 which are securely clamped against the abutment shoulders 22 by a clamping lug '26 extending from the rear of the cover plate l3. The two contact members are separated from each other by a spacing lug 21 provided for that purpose on the the contact members lying in said channel. The

width of the spacing lug 21 is preferably such as to clamp the finger portions 23 against the rear extremities of the forwardly diverging channel walls 23, 23.

The forward portions of the spring fingers 23 are curved away from each other to thereby provide arcuate portions 23 extending into the circular slot I6 on opposite sidesof the diametrical slot I3. The arcuate portions 23 are so formed as to be substantially concentric with the circular slot i6, and are preferably curved on a radius equal to or slightly larger than that of the inner wall 30 of the said circular slot. To provide a definite rotative locked position for the lamp, the arcuate portions 23 of the spring fingers 23 are provided with outwardly extending diametrically opposite notches 3|, 3| preferably located in a plane extending substantially at right angles to the diametrical slot I3. The forward extremities of the arcuate portions 23 are curled outwardly, as indicated at 32, and preferably terminate adjacent the plane of the walls of the diametrical slot l3 so as not to obstruct the same.

The hollowed-out side of the base member H is covered by the previously mentioned cover plate i3 which is secured to the base member by means of rivets 33, preferably of soft brass, embedded in the molded material of the base member and extending through' properly located openings 34 in the cover plate. The side wall it of the base member is preferably recessed an amount equal to the thickness of the cover plate to form a recessed mounting seat 35 therefor, thus providing a flush mounting for the cover plate. A circular opening 36, concentric with the circular slot it in the base member, is provided in the cover plate l3, as well as a slot 31 in alignment with and of the same width as the diametrical slot i3 in the base member. The slot 31 extends from the front of the cover plate back to the circular opening 36, thus providing a passageway thereinto.

As before described, the cover plate 13 is formed at its rear extremity with a clamping lug- 26 which extends into the widened recess 2| at the rear of the base member and clamps the mounting lug 25 on each spring contact member [2 against its co-operating abutment shoulder 22 on the base member. In addition, the cover plate is further provided with the previously referred to spacing lug 21 which extends into the channel l3 in the base member and maintains the spring contact members l2, I! in spaced relation. Circuit connections to the contact members of the socket are made by means of wire leads 38, 33 soldered to the finger portions 23 of the contact members closelyadjacent the bottom wall of the channel l3, and extending out through channels or grooves 33, 33 provided for that purpose in the clamping lug 23 on the cover plate.

The lamp base 40 for co-operation with the above-described socket l0 comprises a cup-shaped body of suitable insulating material preferably of Bakelite and consisting of a bottom or end wall 4| and a cylindrical wall 42. The cylindrical wall is of the proper internal diameter to fit loosely over the end or neck portion 44 of the glass envelope 45 of the lamp 43, to which neck portion the base is united by suitable cement 46. The base 431s provided with three outwardly extending equally spaced, and aligned prongs or pins 41 mounted in the end wall 4| of the base and extending therethrough. However, if desired, the center pin may be omitted and only the two outer pins employed. While not necessary, the pins 41are preferably mounted in a common plane extending radially through the axis of the cylindrical base. The said pins 41 are hollow and are preferably made of brass and nickel plated. To control the extent to their outward projection, which should be slightly less than the total depth of the pin slots in the socket ill, the pins are provided with an annular locating' shoulder 43 intermediate their ends. The

pins may be secured to the end wall 4| of the base either by being molded therein, or by staking, in which the inner edges of the pins are rolled or peaned over onto the inner or rear surface of the end wall 4|. The lamp lead wires 43, 43 extend into the hollow outer pins or prongs 41 and are soldered therein, preferably by dipping the hollow open-ended pins in a bath of molten solder.

Where the base and socket construction com.- prising my invention is to be used for mounting a double-ended lamp such as a fluorescent discharge tube, as shown at 43 in Fig. 1, a base 40 is mounted on each end of the lamp in such a way that alL of the pins or prongs 41 lie in a common plane. The filamentary electrode 50 at each end of the lamp is connected by the lead wires 43 to the two outer pins 41 of the adjacent base 40, leaving the center pin in each base as a dummy pin. A pair of sockets l3, l3 constructed in accordance with my invention are mounted on a suitable fixture 5| so as to be in alignment with each other. The sockets should be spaced the proper amount from each other to thereby freely receive the lamp 43 therebetween. The sockets are accordingly spaced so that the distance between the opposing or facing surfaces l4, I4 is slightly greater than the length of the lamp 43- exclusive of the projecting pins or prongs 41. The socket lead wires 33, 33 extend through openings in the mounting wall 52 of the fixture BI and are connected to suitable starting and operating apparatus which may be mounted, if desired, in the fixture.

To insert the lamp as m the sockets no, lo, the

lamp is first placed in the position shown in Fig. 1 with the pins 41 in alignment with the diametrical pin slots l3 and 31 in the sockets. The lamp is then inserted between the sockets by a straight inward movement, the pins 41 at each end of the lamp being guided at the same time into the cooperating diametrical pin slots in the sockets. The inward movement of the lamp is continued until the two outer pins at each end of the lamp are brought into alignment with, and the center or dummy pin coincides with the center of the circular slot IS in the socket base member Ii. To so align the outer base pins 41 with the said circular slot, the circular opening 33 in the socket cover plate I3 is made of the same diameter as, or slightly greater than the distance d (Fig. 1) between the outer sides of the two outer base pins 41. Thus, that portion 53 of the wall of the circular opening 36 opposite or in line with the diametrical pin slot 31 constitutes a stop for limiting the inward movement of the lamp and simultaneously aligning the outer base pins with the circular pin slots IS in each socket. The center or dummy pin at each end of the lamp inof the proper internal face of the Bakelite disc 5'! 2,187,174 the first pin inserted cannot be jammed into the front portion of the circular pin slot It when moved into alignment therewith.

Whe the outer base pins at each end of the lamp ave been moved into alignment with the circular pin slot I I in each socket. as described above, the lamp may then be readily rotated in either direction against the spring resistance of the contact members I! in each socket. By rotating the lamp in either direction, the two outer pins or prongs I! in each base will engage the arcuate portions "of the spring contact members i2 and so flex the said members. when the lamp has been rotated approximately ninety degrees, the two outer base pins at each end of the lamp will be brought into alignment with, and will become locked in the notches II in the spring contact members if, thereby providing a positive lock against unwarranted or premature disengagement of the lamp from the sockets. Thus where the lamp is to be mounted on a ceiling, so as to occupy an inverted position, there is no danger whatever of the lamp accidentally falling out of the sockets. During the above described rotation of the lamp in the sockets i0. iii, the center or dummy pins at each end of the lamp co-operate with the diametrical pin slot walls to thereby fix the axis of lamp rotation in a direction transversely of said diametrical slots.

In the modified form of lamp base shown in Fig. 7, the body portion thereof comprises a cylindrical metallic collar It provided with an inwardly extending end flange II forming a part of the base end wall. The collar 54 with its flange 55 is preferably punched as a unit from sheet brass, and is preferably nickel plated. The flange 55 is of uniform inward extent so as to thereby provide a centrally located circular opening 58 in the base end wall. This opening I! is closed by a disc 51 of insulating material, preferably Bakelite, which is molded to the ofl'set edge 58 of the flange 55 so as to lie flush with the outer surface of said flange. The desired number of base pins 41 (i. e., either two or three) are mounted in the Bakelite disc 51 in the same manner as in the previous form of base. The inner suris formed with a centrally located circular recess is for the purpose of accommodating therein the exhaust tip of the lamp bulb. 'I'he brass cylindrical collar 54 is diameter to flt loosely over the neck portion 44 of the glass lamp envelope-l5,

' and it is secured thereto in the same manner as before, i. e., by suitable cement ll.

The use of abrass collar 54 to encircle the neck portion 44 of the glass lamp envelope 5 obviates any danger of breakage of s the contraction of shrinkage of the encircling collar or band of the base upon cooling, following the base cementing operation. In addition, the use of the relatively thin brass collar 54 together with the centrally located Bakelite disc 5! permits closer mounting of the base to the end'of the 75 the socket in may be somewhat widened and: the

lamp envelope 45 since the said disc 51 can extend into the recess in the end of the envelope provided by the stem tube flare. The result of such a closer mounting is to reduce the longitudinal extent of the darkened or unillumlnated portions at each end of the lamp during operation, occasioned by the presence of a base thereat. This is particularly advantageous in cases where a series of lamps 43 are to be'mounted in alignment with one another so as to approximate a continuous line of light. In ,this connection,

'bers mounted within said neck portion by- 3 opposite faces each provided with a pair of contact members l2, I! thus 1011111118, in enact, a

double socket for mounting two lamps 43 end to end and. in axial alignment to thereby approximate a continuous line of light.

From the above description, it is evident that I have provided an.improved base and socket construction for the mounting of electric lamps and similar devices, pe. whereby the same may be positively locked in said sockets to guard against unwarranted disengagement therefrom. Furthermore, the contact members of my improved socket are well concealed by the cover plate thereof so as to prevent short circuits therebetween as well as iniurious shocks therefrom.

What I .claim as new and desire to secure by Letters Patent of the United States is:

l. A socket for electric lamps and similar devices comprising a member of insulating material, said member being provided in a face thereof with diametrically opposite arcuate slots and also with a slot extending diametrically of and intersecting both of said arcuate slots, said diametrical slot extending'to an edge of said face, and spring contact members mounted in'sald member adjacent said arcuate slots and on opposite sides of said diametrical slot.

2. A socket for electric lamps and similar devices comprislng a member of insulating material, said member being provided in'a face thereof with diametrically opposite arcuate slots and also with a slot extending diametrically of and intersecting both of said arcuate slots, said diametrical slot extending tov an edge of said face, and spring contact members mounted in said member adjacent said arcuate slots and on. opposite sides of said diametrical slot, said contact members being provided notches. a v

3. A socket for electric lamps and similar devices comprising a member of insulating material, said member being provided in a face thereof with a circular slot and 'also with a slot extending diametrically of said cireular slot and continuing to an edge of said face, and spring contact memsaid circular slot on oppoparticularly of the double-ended with diametrically opposite lo I site sides of said diametrical slot, said contact of with a circular slot and also with a slot extending diametrically of said circular slot and continuing to an edge of said face. and spring contact members mounted within said member and having arcuate portions disposed in said circular slot on opposite sides of said diametrical slot, said with the inner wall of said circular slot.

5. A socket for electric lamps and similar devices comprising-a member of insulating material. said member being provided in a face thereof with a circular slot and also with a .slot extending diametrically of said circular slot and continuing to an edge of said face, and spring contact members mounted within said member and having arcuate portions disposed in said circular slot on opposite sides of said diametrical slot, said arouate portions being substantially concentric with the inner wall of said circular slot and having diametrically opposite notches disposed in a arcuate portions being substantially concentric 4. plane extending substantially transversely of said diametrical slot. I

6. A socket for electric lamps and similar devices comprising a base member of insulating material, said base member being provided in a face thereof with a circular slot and also with a slot extending diametrically of said circular slot and provided with a continuing to an edge of said face. spring contact members mounted within said base member and having arcuate portions disposed in said circular slot on opposite sides of said diametrical slot, said arcuate portions being substantially concentric with the inner wall of said circular slot, and a cover plate of insulating material secured to said base member, said cover plate being provided with a circular opening concentric with said circular slot and of a diameter slightly larger than that of said arcuate portions and also being slot in alignment with said diametricalslot and extending to the edge of said cover plate.

7. In combination, an electric device provided with a base having a plurality of aligned pins extending outwardly therefrom, and a socket for co-operation therewith, said socket comprising a member of insulating material having diametrically opposite arcuate slots and a slot extending diametrically of and intersecting both of said arcuate slots, said diametrical slot extending to an edge of said member, and spring contact members mounted within said arcuate slots on opposite sides of said diametrical slot and constructed and arranged to engage certain of said pins upon their rotation in said arcuate slots.

8. In combination, a double-ended electric device having a base at each end, each of said bases having a plurality of aligned pins extending outwardly therefrom, all of said pins lying in a common plane, and a pair of spaced opposed sockets constructed and arranged to receive and mount the said .electric device therebetween, the opposing faces of said sockets being provided with circular pin slots and aligned straight pin slots extending diametrically of said circular slots and continuing to the front edge of said faces, said sockets also having spring contact members mounted in said circular slots on opposite sides of said diametrical slots and constructed and arranged to engage certain of said pins upon their 50 rotation in said arcuate slots.

mam-r4.

9. In combination, a double-ended electric device having a base at each end. each of said bases having a plurality of aligned pins extending outwardly therefrom, all of said pins lying in a common plane, and a pair of spaced opposed sockets constructed and arranged to receive and mount the said electric device therebetween, said sockets being provided with opposing circular pin slots having diametrically opposite spring contact members therein, said sockets also having aligned straight pin slots extending rearwardly from the front edge thereof and, diametrically intersecting said circular slots whereby the said electric device may be mounted in said sockets by insertion of the pins at each end of the device in the said straight pin slots in the adjacent socket followed by straight rearward movement of said device until the outer pins of each base are brought into alignment with the said circular slots whence the device may then be rotated in either direction to thereby bring the said outer pins into engagement with said contact members.

10. In combination, a double-ended electric device having a base at each end, each of said bases having a plurality of aligned pins extending outwardly therefrom, all of said pins lying. in a common plane, and a pair of spaced opposed sockets constructed and arranged to receive and mount the said electric device therebetween, said sockets being provided with opposing circular pin slots having diametrically opposite spring contact members therein, the spring contact members in each socket being provided with diametrically opposite notches, said sockets also having aligned straight pin slots extending rearwardly from the front edge thereof and diametrically intersecting said circular slots whereby the said electric device may be mounted in said sockets by insertion of the pins at each end of the device in the said straight pin slots in the adjacent socket followed by straight rearward movement of said device until the outer pins of each base' are brought into alignment with the said circular slots whence the device may then be rotated in either direction to thereby bring the said outer pins into interlocking engagement with the said notches in said contact members.

J. MARSHAUS.

Images