US2709097A - Electric swivel fitting - Google Patents

Description

May 24, 1955 M. LEARY' 2,709,097 ELECTRIC SWIVEL FITTING Fil ed July 10, 1952 III Snnentor M0 96; [ET/9R) attorney United States Patent 6 ELECTRIC SWIVEL FITTING Michael Leary, New York, N. Y., assignor to Walter Freeman, New York, N. Y.

Application July 10, 1952, Serial No. 298,120 8 Claims. (Cl. 287-92) This invention relates to an electric swivel fitting, i. e. to an electric fitting having two members, one of which can be swivelled relative to the other about two axes at right angles to one another. In a fitting of this type at least one of the members is tubular and one of the axes of rotation coincides with the longitudinal axis of said tubular member. For convenience, the axis which is coincident with the longitudinal axis of the tubular member, hereinafter will be referred to as the longitudinal axis of rotation and the other as the transverse axis of rotation.

More particularly the invention relates to a fitting of the character described in which a casing is provided having an internal body disposed wholly within the same and rotatable with respect thereto about the transverse axis, the casing being formed with a slot and the internal body carrying a tubular member that extends through the slot and thereby limits the extent of transverse rotation.

customarily in a fitting of the character described the transverse rotation does not exceed 90 in order that an opening which is provided in the body for accommodation of an electric wire cannot be seen through the slot. This opening usually is quite large whereby to make certain that the wire is not pinched, cut or mutiliated. Therefore if the slot were long enough to permit a transverse rotation of 180 the opening could be seen through the slot. Accordingly, as just indicated, pursuant to standard practice the slot limits rotation about the transverse axis to 90 despite the fact that a transverse rotation of 180 would be highly desirable.

Primarily it is an object of the present invention to provide an electric swivel fitting of the character described in which the slot in the casing is long enough to permit transverse rotation of the internal body through a full 180, or more if desired, and yet in which the opening in the internal body never can be seen through the slot.

It is another object of this invention to provide a fitting of the character described having a unique arrangement for preventing the exposure of the inside of the casing through the slot.

It is another object of this invention to provide a fitting of the character described having novel flexible means movable with the internal body to conceal exposure of said body through the slot.

It is another object of this invention to provide a fitting of the character described having in conjunction with the concealing means above referred to, a skeletonized revolvable internal body whereby maximum freedom is aiiorded for an electric wire extending through the fitting.

It is another object of this invention to provide a fitting of the character described which constitutes but few simple and sturdy parts and is easy and inexpensive to manufacture.

Other objects of this invention will in part be obvious and in part will be pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements and arrangements of parts which will be exemplified in the device herein- 2,709,097 Patented May 24, 1955 after described and of which the scope of application will be indicated in the appended claims.

In the accompanying drawings in which is shown one of the various possible embodiments of the invention,

Fig. 1 is a side view of an electric fixture including a swivel fitting constructed in accordance with the present invention;

Fig. 2 is an enlarged front view of the fitting alone;

Fig. 3 is an end View of said fitting;

Fig. 4 is a sectional view taken substantially along the line 44 of Fig. 2;

Fig. 5 is a sectional View taken substantially along the line 5-5 of Fig. 4;

Fig. 6 is a side view of one of the two halves of which the casing is composed;

Fig. 7 is a side view of the rotatable internal body as it appears when removed from the casing; and

Fig. 8 is a sectional view taken substantially along the line 8-8 of Fig. 5.

Referring now in detail to the drawings, the reference numeral 10 denotes an electric fixture including a stem ceiling support 12 and a bowl reflector 14 joined by a swivel fitting 16 embodying the present invention.

it will be understood that, although the fixture here is shown as including a specific support and a specific lampholder (bowl reflector), the use of the swivel fitting is not limited thereto, but in general the fitting can be em ployed to join any two parts of an electric fixture which are to be relatively movable about two perpendicular axes and to be interconnected by a concealed electric wire extending from one part to the other through the fitting.

Said fitting comprises a hollow casing 13 which preferably is elongated and to simplify manufacture may be made in two parts. For instance the casing is split approximately parallel to its longitudinal axis so as to include a first half 20 and a second half 22 which are provided with suitable means for detachably securing the same to one another. For instance, one of the halves may include a pair of tapped openings 24 and the other half a pair of clear openings 26 in registry with the tapped openings. A pair of headed bolts 23 extending through the clear openings are threaded into the tapped openings to hold the halves of the casing together.

One end, 6. g. the end 30, of the casing is of broad semi-circular external shape and the other end 32 may be of narrow trapezoidal external shape. The outside of the casing converges smoothly from the broad end 30 to the narrow end 32. This configuration is entirely optional and, obviously, it is not a necessary element of a swivel fitting embodying this invention. I

The casing must have a cylindrical cavity 34 which preferably is located at one of the ends, and most conveniently at the broad round end 30. This cavity may be constituted by a pair of facing registered circular shallow depressions 36 in the two casing halves 20, 22.

Rotatable in said cylindrical cavity is an internal body 38 of generally cylindrical shape, of the same height as and of slightly smaller diameter than the cavity. More specifically said body includes two parallel spaced circular disks 40 joined by a base wall 42 integral with the disks. To facilitate assembly the cylinder thus formed may be slightly mutilated at said base 42 as by the removal of a shallow segment. By virtue of such construction the cylindrical internal body not only is hollow but its entire periphery is absent except for the short part constituted by the wall 42. Thereby an electric wire in the fitting can extend from any point between the disks save where it is blocked by the wall 42. This forms for accommodation of the wire an opening so large that it would be unsightly even in a conventional present-day swivel fitting which permits a transverse rotation of only 90. Nevertheless for reasons which shortly will be apparent this large opening will not be visible in a fixture embodying the present invention.

The internal body 38 carries a tubular member in the form of a radially projecting male threaded stud 44 which protrudes from the casing through an arcuate slot 46 in the curved periphery of the rounded end of the casing. In accordance with this invention the angular length of said slot is sufiiciently great to permit the internal body to be rotated about the transverse axis over any desired are, e. 'g. 180. Said slot do may comprise facing registered indentations 48 in the edges of the casing halves.

The stud 44 passes through a suitable opening in the wall 42 whereby to provide a wire entryway to the inside of the internal body. Said stud is secured against rotation relative to the body in any conventional manner as for instance by staking.

In accordance with the principal feature of the instant invention the fixture 16 includes means to conceal the internal body from view through the slot 46 and thereby to conceal the large opening in said body which accommodates an electric wire as the body is rotated. Said means comprises a long wide flexible member frictionally engaging the interior surface of the casing at both sides and ends of the slot, located in part between the body and casing and movable with the body. More specifically said means simply constitutes a broad thin strip 50 of resilient material and preferably a springy strip of sheet metal. The strip is secured to the internal body in a position for its width to lie perpendicular to the plane of the disks it) and so that it can be wrapped about the periphery of said body. Said strip is sufficiently broad to span the distance between the disks and to overlie the edges of the disks but desirably does 3 not extend beyond the same. I

The length of the strip should be at least slightly in excess of twice the length of travel of the internal body. That is to say, if the internal body can be turned through 180 the strip should have a length at least equal to 360 of the circumference of the body. If the arc through which the body is to sweep is either more or less, the length of the strip can be changed in proportion. It will be understood that the foregoing criterion for the length of the strip is merely a mini- -31 mode; the strip can be and preferably is somewhat longer. If of minimum length the strip should be centered 'with respect to the stud 2-4, and for symmetry of construc; tion the strip usually will be centered about said stud in any event.

Said strip conveniently is provided with an opening 52 which receives the stud 44, the stud having a shoulder 54 which permanenhy holds the strip against the wall 42 of the internal body. The opening 52 in the strip may be of non-circular outline and the external crosssection of thestud at this point of matching outline whereby once the strip is secured to the stud it cannot turn with respect thereto. It should be borne in mind nevertheless that, as soon will be apparent, other constraints are provided for the strip and therefore this use of the non-circular opening and section is not essential.

Sufiicie'nt space is provided within the casing 18 to permit the ends of the strip to frictionally slide along the interior surface of the casing as the body is rotated. More particularly I provide the casing with Ways '56 to slidably receive the moving ends of the strip. The distance between the lateral edges of the ways may just be suflicient to accommodate the strip. Thus the strip in any event would be fixed ag'a'ins't rotary movement with respect to the longitudinal axis of the stud 44.

'Better to frictionallyrestr'ain the strip during its sliding movement, the casing includes rails '58 spaced inwardly from the ways '56 thereby to define slots ill within which the strip 'frictionally slides as the internal body rotates. These slots are wide enough barely to slidably pass the strip so that the strip will frictionally engage the sides of the slots and particularly the ways 56.

l have found that if the strip has a relaxed shape (see F i g. 7) in which its radius of curvature exceeds the radius of curvature of the disks 4% the strip when constrained to lie within the slots 66 will engage the ways 56 with sufiicient frictional force to retain the internal body in any adjusted position against accidental displacement. Thus the strip 5% not only serves to block visual access through the slot 46 to the body 3-5 but also to retain said body in any given relationship with respect to the casing.

The casing also is provided with a tubular member which is mounted for axial rotation relative thereto about a longitudinal axis perpendicular to the transve se axis of rotation of the internal body. Said tubular member is carried by the casing 13 and is located at a point spaced from the internal body, more specifically at the opposite end of the casing from the internal body.

The second tubular member consists of a sleeve 62 journalled in a shoulder 64 upstanding at one end of the casing half 26*. Said sleeve extends to both sides of the shoulder. The end of the sleeve which projects from the casing is formed with an enlarged tapped cup 66 for connection to an element of an electric fixture, as for instance the ceiling support 12. The end of the sleeve which extends into the casing is peened to hold captive a washer d8 surrounding the sleeve. Said washer serves as an abutment member holding under compression between itself and the shoulder 64 a helical spring 70 that encircles the sleeve. The function of the spring is to frictionally restrain the sleeve 62 and thereby hold out against accidental displacement in any selected angular position.

Desirably suitable means is included to limit rotation of the sleeve to slightly less than 360 with respect to the casing. conventionally said means includes a slender projection on the sleeve adapted to abut a slender pro- ;Iection carried by the shoulder.

It thus will be seen that there is provided a device which 3C1 ieves all the obiects of the invention and is well adapted to meet the conditions or" practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein described, or shown in the accompanying drawings, is to be interpreted as illustrative and not in a limiting sense.

Having thus described the invention, there "is claimed as new and desired to be secured by Letters Patent:

1. An electric swivel fitting'co'mprising a hollow casing having an elongated internal cavity, said casing including a semi-cylindrical portion at one end and having side walls extending tangentially from opposite sides of said semicylindrical portion and converging toward one another and extending towards the other end, the axis of the semicylindri-cal portion'intersecting the longitudinal axis of the cavity, said casing having an opening at the other end, the axis whereof is coincident with the longitudinal axis of the cavity, said scrub-cylindrical portion including an approximately semi-circular slot concentric with the axis of the semi-cylindrical portion, a hollow, internal, cylindrical body rotatable within the sernicylindrical portion, a hollow stud carried by said body and protruding radially outwardly therefrom through the slot, said body being open on the side opposite said slot, and a strip of thin resilient sheet material carried by and secured to the body so as to be movable integrally with the body within the casing, said strip being wider than the slot and extending on each side of the'stud a distance at least as great as the length of the semi-circular slot so as to fully conceal the body from view through the slot, the relaxed shape of the resilient s.rip having a radius of curvature :greater than that of the cylindrical body, said strip lying between said body and the semi-cylindrical portion of the casing over a substantial arc and also lying against the side walls of said casing immediately adjacent the semi-cylindrical portion thereof whereby said strip frictionally engages the inside of the casing to retain the body in any adjusted position and whereby an electric wire may be threaded without deflection through said stud and cavity and will not be pinched or mutilated when the internal body is oscillated.

2. A fitting as set forth in claim 1 wherein the side walls include ways against which the strip rubs when the body is rotated.

3. A fitting as set forth in claim 1 wherein the internal body constitutes a pair of registered, spaced, parallel, circular discs joined by a wall which extends less than half way around the peripheries of said discs, the stud being carried by said wall.

4. A fitting as set forth in claim 1 wherein the side walls include ways against which the strip rubs when the body is rotated and rails spaced from the ways to define slots for guiding the strip.

5. A fitting as set forth in claim 1 wherein the strip is fabricated from springy sheet metal.

6. An electric swivel fitting comprising a hollow casing having an elongated internal cavity, said casing including a semi-cylindrical portion at one end and having side walls extending away from opposite sides of said semicylindrical portion toward the other end of the casing, the axis of said semi-cylindrical portion intersecting the longitudinal axis of the cavity, said casing having an opening at the other end the longitudinal axis whereof is coincident with the longitudinal axis of the cavity, said semicylindrical portion including an approximately semi-circular slot coincident with the axis of the semi-cylindrical portion, a hollow, internal cylindrical body rotatable within the serni-eylindrical portion, a hollow stud carried by said body and protruding radially outwardly therefrom through the slot, said body being open on the side opposite said slot, and a strip of thin resilient sheet material carried by and secured to the body so as to be movable integrally with the body within the casing, said strip being wider than the slot and extending on each side of the stud a distance at least as great as the length of the semi-circular slot so as to fully conceal the body from view through the slot, the relaxed shape of the resilient strip having a radius of curvature greater than that of the cylindrical body, said strip lying between said body and the semi-cylindrical portion of the casing over a substantial arc and also lying against the side walls of said casing immediately adjacent the semi-cylindrical portion thereof whereby said strip frictionally engages the inside of the casing to retain the body in any adjusted position and whereby an electric wire may be threaded without deflection through said stud and cavity and will not be pinched or mutilated when the external body is oscillated.

7. An electric swivel fitting comprising a hollow casing having a cylindrical internal cavity, said casing including a slot concentric with the axis of the cavity, a cylindrical internal hollow body rotatable within the cavity and hav- 6 ing a circular section extending over an arc of more than 180 whereby the body is snug within the cavity, said body being open on the side opposite said slot, a hollow stud carried by the body and protruding radially outwardly therefrom through the slot, and a strip of thin resilient sheet material carried by the body and rigidly secured to and movable with the body within the casing, the relaxed shape of the resilient strip having a radius of curvature greater than that of the cylindrical body, said strip being wider than the slot and extending on each side of the stud a distance at least as great as the length of the slot so as to fully conceal view of the body through the slot, said casing including ways against which the strip rubs when the body is rotated.

8. An electric swivel fitting comprising a hollow casing having an elongated internal cavity, said casing including a. semi-cylindrical portion at one end and having side walls extending away from opposite sides of said semicylindrical portion toward the other end of the casing, the axis of said semi-cylindrical portion intersecting the longitudinal axis of the cavity, said casing having an opening at the other end the longitudinal axis whereof is coincident with the longitudinal axis of the cavity, said semi-cylindrical portion including a slot coincident with the axis of the semi-cylindrical portion, a hollow, internal cylindrical body rotatable within the semi-cylindrical portion, a hollow stud carried by said body and protruding radially outwardly therefrom through the slot, said body being open on the side opposite said slot, and a strip of thin resilient sheet material carried by and secured to the body so as to be movable integrally with the body within the casing, said strip being wider than the slot and extending on each side of the stud a distance at least as great as the length of the slot so as to fully conceal the body from view through the slot, the relaxed shape of the resilient strip having a radius of curvature greater than that of the cylindrical body, said strip lying between said body and the semi-cylindrical portion of the casing over a substantial arc and also lying against the side walls of said casing immediately adjacent the semi-cylindrical portion thereof whereby said strip frictionally engages the inside of the casing to retain the body in any adjusted position and whereby an electric wire may be threaded without deflection through said stud and cavity and will not be pinched or mutilated when the external body is oscillated.

References Cited in the file of this patent UNITED STATES PATENTS 794,967 Baird July 18, 1905 1,123,839 Bridges Ian. 5, 1915 1,182,269 Gottschall et al May 9, 1916 1,474,304 Weber Nov. 13, 1923 2,217,407 Hansen Oct. 8, 1940 2,278,356 Livingston Mar. 31, 1942 2,594,242 Wilson Apr. 22, 1952

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