US 3872428 A
An adjustable lampholder is provided which is useful for positioning a light relative to a clamp suitable for clamping on a support. An articualted swivel mount between the lamp and clamp permits a rotary as well as a dual pivoting motion. The swivel portion of the articulated swivel joint includes a firt clevis and ring springs and is attached in swivel relation to an end of a wire lamp guard by an eyelet. The wire lamp guard is securely mounted to a lamp housing by a solid rivet extending through the eyelet, through the lamp housing and through a second end of the wire lamp guard to hold the lamp housing together and to hold the lamp guard to the lamp housing. The articulated portion of the mount is made up of a second clevis mounted to the first and straddling the coil spring of a spring clamp.
Claims available in
Description (OCR text may contain errors)
United States Patent 1 [111 3,872,428
Boisvert Mar. 18, 1975 1 ADJUSTABLE LAMPHOLDER WITH PrimaryExaminer-Richard M. Sheer ARTICULATED SWIVEL MOUNT  Inventor: Roger L. Boisvert, Blackstone,
[73} Assignee: General Electric Company, New
 Filed: Dec. 26, 1973  Appl. No.: 428,191
152] U.S. Cl. 240/52.l, 248/229  Int. Cl. F2lv 21/08  Field of Search 240/52 R, 52 BL, 52.1, 240/52.3, 54 R, 54 A; 248/229  References Cited UNITED STATES PATENTS 1,722,773 7/1929 Stewart 240/52.l X 2,465.519 3/1949 Eastman 240/52.l
2,515,659 7/1950 Michal r 240/52.l 2,727.137 12/1955 Oharenko.... 240/4l.55 X 7.479.500 11/1969 Duddy 240/52.1 X
Attorney, Agent, or FirmP. E. Rochford; P. L. Schlamp  ABSTRACT An adjustable lampholder is provided which is useful for positioning a light relative to a clamp suitable for clamping on a support. An articualted swivel mount between the lamp and clamp permits a rotary as well a dual pivoting motion. The swivel portion of the articulated swivel joint includes a tin clevis and ring springs and is attached in swivel relation to an end of i 4 Claims, 5 Drawing Figures PATENTH] PM I 8 i975 SsiiET 1 [If 2 ADJUSTABLE LAMPHOLDER WITH ARTICULATED SWIVEL MOUNT BACKGROUND The present invention relates to an adjustable lampholder as is customarily used temporarily in lighting applications where the positioning of a lamp relative to its support makes it desirable that the lamp be swiveled and turned and oriented in order to properly position it relative to the object to be illuminated on a temporary basis.
Such lamps have been known in the past and one form is the so-called trouble light" used by auto mechanics and others in providing temporary illumination on the specific work area where repair work is to be performed by the mechanic. Another common use is in photographic applications. Such lampholders have been used where the photographer wants to position lights on a subject to be photographed. Many such lampholders use a spring biased clamp for supporting the lamp socket on a bar or rail. The present invention relates primarily to this latter type of article and particularly to one having an articulated swivel joint extending between and connecting the socket portion of the light source to the clamp portion thereof. Articles of this sort have been known in the past and are taught in such US. Pat. Nos. as 1,690,491; 2,557,532; 2,727,137; 3,086,107; 3,183,384 and 3,479,500. Other patents are directed primarily to the type of swivel joint which operates by frictional engagement of the various parts so that once the swivel joint is placed in a certain orientation or position, it will remain in that position until intentionally repositioned. One article which provides articulated swivel motion between a clamp and bulb socket is the portable clamp light sold under catalog numbers GE3945 and GE3946 and available from the General Electric Company. This article has a spring biased clamp and has a double clevis mounted to the coil spring portion of the clamp to provide articulated motion between clamp and lamp socket.
One problem encountered in connection with such lamps is that where heavier lamp bulbs are employed, the force of gravity acting through the articulated swivel joint tends to cause the light to fall or to cause the joint to swivel beyond the point to which it is set by the user. This is particularly true where such joints are used in connection with larger bulbs held within protective enclosures commonly described as wire guards or cages for protecting the contained light bulb from impact. Such impact may occur when the lampholder is placed on a surface particularly in a heated condition or if some article should strike the bulb. It has been found that where some scheme for more firm gripping of the bulb housing has been worked out, there has been a resultant damage to the lamp socket housing in the manufacturing process and loss of production for this reason.
Another problem encountered is that of cost of articles used in fabrication of such articulated swivel joints where a multiplicity of parts and operations are necessary in order to form a suitable joint.
OBJECTS It is accordingly one object of the present invention to provide a lampholder having a relatively high capability to hold the light in a selected position.
pointed out in the description which follows.
SUMMARY OF THE INVENTION In one of its broader aspects,'objects of this invention are achieved by providing a lampholder with a wire guard at one end to protect a bulb in a lamp housing and with a spring clamp at the other. The lamp housing is made up of a lamp socket and switch within an insulating housing. The spring clamp permits the lampholder to be clasped onto a support and is attached to the lamp housing of the lampholder through an articulated swivel joint. The insulating housing is made up of two half shells having an assembly rivet hole extending through both half shells. The lamp guard is formed of wire and has two tines which are held to the insulating housing at looped ends of the tines. One of the tines is linked by a swivel joint to a clevis. The swivel joint is made up of an eyelet extending through the loop of the tine, through a hole in the bite of the clevis and through a ring spring which generates spring pressure between the tine and the clevis. A rivet extends through the second tine, the housing and the eyelet and holds these together without interfering with operation of the swivel joint.
A second clevis is held within the jaws of the first in pivoting relation and a coil spring of a spring clamp is held-within the jaws of the second clevis.
vention illustrating one pivot motion feasible for a clamp portion of the lampholder.
FIG. 2 is a side elevation of a portion of the article of FIG. 1 showing another pivot motion of an articulated joint of the lampholder.
FIG. 3 is a detailed side elevational view, in part in section, of a lamp housing, rivet and articulated joint assembly detailing the structure as illustrated in FIG. 1.
FIG. 4 is an exploded perspective view of a preassembly form and arrangement of components of the structure illustrated in FIG. 3.
FIG. 5 is an exploded perspective view of the elements of the articulated joint portion of the article in relation to a riveted swivel joint assembly.
DESCRIPTION OF THE PREFERRED I EMBODIMENT forms which permit light to be transmitted while protecting a lamp bulb within the guard. The tines or similar forked attachment means are held to the lamp housing so that a lamp extending from the socket end 24 of lamp housing 10 is protected by the wire rings 18 which extend about the space occupied by the fragile glass envelope of the bulb.
Opposite the socket end 24 of lamp housing 10 is a switch knob 26 which knob may be turned to energize or de-energize the filament of a lamp in socket 24. Current is supplied by the parallel pair of insulated wires 28 to a lamp extending from housing 10.
The lamp housing itself is made up of two insulating half shells 30 and 32 which are held together by a rivet 34 extending therethrough as best seen in FIG. 3. In FIG. 3 the insulating halves 30 and 32 are shown schematically in phantom to better illustrate the rivet 34. Rivet 34 has a head 36 and an upset end 38b. In FIGS. 4 and 5, the rivet 34 has straight end 38a which is the form of the rivet before it is mechanicallyupset as illustrated in FIG. 3. Its head bears against a looped end 40 of tine and holds the looped end against the upper half shell of housing 10. An integral collar 42 of rivet 34 serves as a spacer within the looped end of tine 20 and bears at a shoulder 44 against the upper half shell 30 of housing 10. A pair of protrusions 46 formed integrally with half shell 30 on its external surface and located on each side of tine 20 holds the time 20 in alignment relative to the housing 10.
The upset end 38b of rivet 34 does not bear directly against the lower half shell 32 of insulating housing 10. Rather, an eyelet head bears against insulating housing 10 at a collar 48 formed integrally with the lower half shell 32. The eyelet 52 is in turn held at its head 50 against half shell 32 by rivet 34 as is now explained. The eyelet 52 extends through a looped end 54 of tine 22, through a hole 56 in the bottom 58 or bite portion of a first clevis 60, through a pair of ring springs 62 and 64 and terminates in an outwardly deformed end 66!) as seen in FIG. 3. The deformed end 38!) of rivet 34 accordingly bears against the deformed end 6612 of eyelet 60. Prior to deformation the end 66a has the form shown in FIG. 4.
Clevis has a hole in each of its arms, one of these holes 68 in arm 70 being threaded and the other hole 72 in arm 74 being unthreaded. A screw 76 having head 78 and threaded end 80 fits through hole 72 and is threaded into hole 78 to capture the bite portion 82 of a second clevis 84 in the conventional manner to permit pivoting motion of the second clevis relative to the first.
The second clevis 84 also has an unthreaded hole 86 and an aligned threaded hole 88. These holes accept a screw 90 which screw has head 92 and threaded end 94.
The second clevis 84 has contoured arms 96 and 98 and these contoured arms are formed to fit about the strands 102, 104 and 106 of the coil spring 100. Tightening screw 90 increases or decreases frictional engagement between coil spring and contoured arms 96 and 98.
Coil spring 100 is the principal spring element of a spring clamp 108. Spring clamp 108 is made up of the coil spring 100, the arms 110 and 112 and the interlocked opposed cross pieces 114 and 116 which may have rubber covered clamp ends in the form of loops 118 and 120 as illustrated in the figures.
The looped ends 118 and 120 are the active clamp elements which actually bear against and grip an object serving as a supporting element for the lampholder such as a bar or rail not shown. Looped ends 118 and 120 may be separated by applying hand pressure along the arms 110 and 112 of the spring clamp 108. Once separated, the rubber covered looped ends 118 and 120 may be relaxed onto an object which is to support the lampholder in manner well known in the art.
Further well known in the art, the coil spring 100 is able to pivot as illustrated in FIG. 1 through a wide are marked 122 in FIG. 1 by the frictional fit of the coil spring within the contoured arms 96 and 98 of clevis 84. The clamp assumes the position shown by phantom clamp 128 at one end of the arc and assumes an opposite position indicated by phantom clamp 138 at the other extreme of the arc.
The use of the first and second clevis to provide an articulated motion at the joint which they form is also well known in the art and has been employed in the clamp product referred to above in the background statement.
What is new and unique in this product is the combination of eyelet and concentric rivet and springsand looped tines with the lamp housing to provide a lampholder which is easily and accurately positionable and which holds the position to which it'is set withreliability and accuracy. Because of its simple construction breakage in manufacture of this lampholder is reduced and a very servicable product is achieved.
In particular, the novel combination of elements includes a subcombination of the looped end 54 of tine 22 with clevis 60 and with ring springs 62 and 64, all held in spring compression contact by eyelet 52. This subcombination is assembled independently of the housing 10 and the spring pressure is maintained between its elements independently of housing 10. Moreover the swivel motion of which the lampholder is capable is accomplished at the interface between looped end 54 of tine 22 and bottom 58 of clevis 60. The development of spring pressure at this swivel joint and the maintenance of spring pressure is independent of the housing 10 andthe variation of dimensions of the parts as 30 and 32 of the housing.
Only after the swivel joint subassembly is fully assembled and operational is the assembly made of the other elements of the lampholder. Such assembly is accomplished by inserting rivet 34 through the looped end 40 of the other tine 20, through the assembled lamp housing, and through the hollow of eyelet 52. Upsetting end 38a of rivet 34 to the 38b form locks the lamp housing between the tines of the lamp guard and also locks the first clevis of articulated joint 16 to the combined housing and lamp guard.
The ring spring element need not be a ring form of spring nor a single spring element. It may be a single element, a double element as shown, or may be an alternative form of spring means. Also the spring means is most conveniently located in the trough of the clevis as it forces the clevis surface against the surface of looped end of tine 22 or against any other suitable means for attaching the lamp guard to the clevis. However it may be located between the looped end 54 and clevis 60 or it may be located between the eyelet head 50 and the looped end 54.
Tines 20 and 22 may conveniently have the form of wire strands in which case the ends may be looped as shown to form a hole for assembly onto a rivet. They may also have the form of strips with an assembly hole formed in the strip end.
Eyelet 52 may have a stepped outer diameter as shown or may have a more uniform diameter and its form is not critical to the operation of the invention. The stepped diameter may be helpful in centering the assembled parts and providing greater strength where greater strain is applied.
Clevis 60 is a conventional part and it is its combination into the new structure taught which makes possible the improved results obtained. Similarly rivet 34 is not unique but its combination with eyelet 52 and the other elements of the combination provide a uniquely economical and reliable structure.
What is claimed as new and desired to be secured by Letters Patent of the United States is:
l. A lampholder comprising,
a. an insulating lamp housing having two half shells,
b. a lamp guard,
c. forked attachment means extending from said lamp guard for attachment at each side of said lamp housing, said attachment means comprising a pair of tines, each having a hole therein;
(1. lampholder mounting means,
1 e. and an articulated swivel joint between the mounting means and housing,
f. said articulated swivel joint including a clevis having its bight portion proximate one of the tines of said guard,
g. said clevis having a hole at the bight portion and said hole being aligned with the hole of said one tine of said forked attachment means,
h. spring means between the clevis and the mounting means,
i. an eyelet extending through said aligned holes and holding said one tine of said attachment means, said clevis and said spring means together under spring pressure to permit swiveling of said clevis relative to said one tine of said attachment means, and
j. an assembly rivet extending through the other tine of said attachment means, through said housing and through the eyelet to hold said housing assembled and to hold said lamp guard to said housing.
2. The lampholder of claim 1, wherein said pair of tines is a pair of wire tines.
3. The lampholder of claim 2, wherein the wire tines have looped ends forming said holes.
4. The lampholder of claim 1, wherein the spring means is a ring spring.