US2250276A

US2250276A - Wiring device

Info

Publication number: US2250276A
Application number: US325614A
Authority: US
Inventors: Charles E Rutherford; Ducer Arthur O La; Robert H Murphy
Original assignee: Wiremold Co
Current assignee: Wiremold Co
Priority date: 1940-03-23
Filing date: 1940-03-23
Publication date: 1941-07-22
Anticipated expiration: 1958-07-22

Description

July 22, 1941. c. E. RUTHERFORD Erm.

WIRING DEVICE Filed March 25, 1940 4 Sheets-Sheet 1 July 22, 1941. c. E. RUTHERFORD Erm. 2,250,276

WIRING DEVICE Filed March 23, 1940 4 Sheets-Sheet 2 July 22 1941- c. E. RUTHERFORD ETAL. 2,250,275

WIRING DEVICE Filed March 25, 1940 4 Sheets- Sheet 5 ATTORNEYS July 22, 1941- c. E. RUTHERFORD ETAL 2,250,276

w'IRING DEVICE Filed March 23, 19,40

. 4 Sheets-Sheet 4 Patented July 22, 1941 UNITED STATES PATENT OFFICE WIRING DEVICE Charles E. Rutherford, Arthur 0. La Ducer, and

Robert H. Murphy, West Hartford, Conn., assignors to The Wiremold Company, a corpora.-

tion ot Connecticut Application March 23, 1940, Serial No. 325,614

15 Claims.

'The new conduit may be mounted on a wall or other surface in the conventional manner, or it may be embedded in a wall so that the top of the conduit is flush with the surface of the wall. The fluorescent lamp assembly of our invention eliminates a large number of the parts and attachments, as well as numerous critically spaced holes drilled in the receiving wall, heretofore required for fluorescent lamp installations.

Fluorescent lamps of the type comprising an elongated gas-filled tube having an interior coating of a fluorescent material with a separate heating filament at each end of the tube are being used increasingly because of their operating efficiency and because of the numerous colors as well as the excellent simulation of natural daylight which they can be made to produce. The lamps are used not only for general illumination purposes but also for the purpose of illuminating show cases, show windows, and the like. The conventional tubular fluorescent lamp is provided with contacts at both ends and requires a lamp receptacle provided with a lamp socket for each end of each individual lamp. Care must be exercised in the spacing of cooperating lamp receptacles, but in addition to this detail a further problem arises due to the fact that fluorescent lamps of the same nominal size are apt to vary in their overall length to the extent of an eighth of an inch and some times more. Accordingly, the placing of cooperating lamp receptacles for a given fluorescent lamp may not be satisfactory for the reception of a replacement lamp. Furthermore, fluorescent lamps require an auxiliary unit adapted to provide the necessary and distinctly different conditions required for starting the lamps and for operating the lamps after they are started. A separate auxiliary unit is generally required for each lamp and, to permit efficient wiring connectionsshould be positioned in close proximity to the lamp and its receptacles. Conventional auxiliary units must be readily accessible inasmuch as the primary source of failure of these lamp assemblies resides in the starting switch which serves automatically to change from starting to normal operating electrical conditions. A recent advancement in this art consists in the removal of the starting switch (the part most likely to fail) from the auxiliary unit and placing it in the base of one of the pair of cooperating lamp receptacles so that the starting switch may be readily replaced without replacing the entire auxiliary unit.

The fluorescent lamp assembly of the invention comprises a conduit adapted to receive and to hold in adjustable but stationary position all l of the equipment usually employed with fluoresposition and for eihciently directing and distributing light from the lamp in any desired manner.

The new fluorescent lamp assembly comprises a channel-shaped conduit of generally rectangular cross-section having side walls and a bottom wall, each of the side walls being provided with a relatively narrow internal groove running longitudinally of the conduit adjacent the bottom wall thereof and being further provided adjacent the top thereof with an outwardly projecting oiset. Lamp receptacles each having a base adapted to be received within the conduit and an upper portion provided with a lamp socket, are mounted in the conduit by a clamp comprising a strap provided with a cut-out portion adapted to engage the receptacle above the base thereof with the strap extending transversely of the conduit between the offsets at the top of the side walls. The clamp is provided with legs projecting from the ends of the strap downwardly toward the bottom of the conduit to a level below the base of the receptacle. Means associated with said legs are provided to support the bottom of the receptacle base and to hold the receptacle in firm engagement with the clamp strap. A fluorescent lamp auxiliary unit is disposed within the walls of the channel-shaped conduit. This unit comprises a body portion provided with a projecting lip, and is placed in the conduit with the lip lying adjacent the bottom wall of the conduit. A locking device is provided for holding the wiring device in position within the condiut. `The locking device comprises a strap of a length approximately equal to the width of the channel between the grooves at the bottom thereof and having rounded ends which permit the strap to be turned, after insertion over a lip of the wiring device, to enter the in- 0 ternal grooves formed at the base of the conduit. The locking device is preferably provided with a set-screw which may be turned down to engage the lip of the wiring device, thereby forcing the ends of the strap upwardly with locking effect within the internal grooves at the base of the conduit.

A cover member for the conduit is held between the offsets at the top of the side walls of the conduit and is positioned substantially to abut the strap of the receptacle clamp. A cover clamp is provided to cover the joint between the cover member and the strap of the receptacle clamp. lThe cover clamp comprises a strap the ends of which are bent downwardly to engage the outside of the side walls of the conduit at the upper edge thereof.

A reector extends between cooperating lamp receptacles and comprises an elongated troughshaped member having a light-reflecting interior surface. The reflector advantageously is provided with a plurality of scored knock-out portions immediately adjacent one another along the end edges of the reflector. By removing appropriate knock-out portions, the reflector may be mounted in any of a plurality of angular positions relatively to the body of the lamp receptacle.

The apparatus of our invention will be more fully understood by reference to the accompanying drawings in which:

Figure 1 is a side view of the fluorescent lamp assembly of our invention taken substantially along line I-l in Figure 2;

Figure 2 is a plan view of the assembly shown in Figure 1 taken substantially along line 2-2 in Figure l with the cover member of the conduit partially removed;

Figure 3 is a plan of the assembly shown in Figure 1;

Figure 4 is a crosssection taken substantially along line 4-4 in Figure 1;

Figure 5 is a section taken substantially along the line 5-5 in Figure 1;

Figure 6 is a section taken substantially along the line 6 6 in Figure 1;

Figure '7 is a section taken substantially along the line 1--1 in Figure 1;

Figure 8 is a perspective of the form of lamp receptacle clamp shown in Figure 7;

Figure 9 is a perspective from the back of the lamp receptacle shown in Figure 7;

Figure 10 is a perspective of the end fitting on the conduit shown in Figure 1;

Figure 11 is a view of the end fitting shown in Figure 10, taken substantially along the line II-ll in Figure 1 with the lamp receptacle and receptacle clamp removed;

Figure 12 is an end view of another type of lamp receptacle and clamp mounted in a conduit, taken substantially along the line |2-I2 in Figure 1;

Figure 13 is a perspective of the lamp receptacle clamp shown in Figure 12;

Figure 14 is a perspective from the rear of a type of lamp receptacle adapted to be held by the clamp shown in Figure 13;

Figure 15 is a conventional type of starting switch received by the base of the lamp receptacle shown in Figure 14;

Figure 16 is a sectional side view of a conduit elbow having an internal bend and showing one form of conduit connector fitting;

Figure 17 is a longitudinal section through adjacent conduits connected by the fitting shown in Figure 16;

Figure 18 is a cross-section taken substantially along line |8-l8 in Figure 16;

Figure 19 is a perspective of a conduit elbow for connecting conduits disposed along the same plane surface;

Figure 20 is a perspective of the conduit elbow shown in Figure 16;

Figure 21 is a perspective from the rear of a conduit elbow having an external bend;

Figure 22 is a perspective of the interior of a section of a cover member adapted to be bent as indicated by the arrow and dotted lines to provide e. cover for the internal elbow shown in Figures 16 and 20;

Figure 23 is a perspective view of a section of the top of a cover member adapted to be bent as indicated by the arrow and dotted lines to form a cover member for the external elbow shown in Figure 21;

Figure 24 is a side elevation of an assembly in accordance with the invention showing in section two reflectors placed end to end around two adjacent lamps;

Figure 25 is a schematic drawing showing the wiring of adjacent fluorescent lamps;

Figure 26 is a schematic wiring diagram of a fluorescent lamp assembly in which the starting switch is contained within the auxiliary unit;

Figure 27 is a section in elevation of a modified conduit end fitting in position in a conduit;

Figure 28 is a section taken substantially along the line 28-28 in Figure 27;

Figure 29 is a perspective of the end fitting shown in Figures 27 and 28, showing the knockout portions in the end wall thereof;

Figure 30 is a composite plan looking downwardly into adjacent reectors before they are interconnected and showing end pieces and a. connecting strap for the adjacent reflectors;

Figure 3l is a cross-section across the end of one reflector showing the relative positions of the reflector, shown in section in Figure 32, and the connecting strap, shown in section in Figure 33;

Figure 34 is an end view of the reflector shown in Figure 30, showing the position at the end of the reflector of the end piece shown in Figure 35;

Figure 36 is a plan of a trough-shaped reflector provided at the end with a plurality of immediately adjacent knock-out portions;

Figure 37 is a perspective of the interior of a conduit, showing a cable fastened to the conduit bottom and wires leading into the interior of the conduit; and

Figure 38 is a perspective oi the interior of a conduit showing the connection of a cable to the end tting for the conduit shown in Figures 27-29.

Referring to Figures 1 and 2 of the drawings, the fluorescent lamp assembly of the invention comprises a channel-shaped conduit of gener-Y ally rectangular cross-section having side walls 40 and a bottom wall 4l. Each of the side walls is provided with a relatively narrow internal groove 42 running longitudinally of the conduit adjacent the bottom wall of the conduit. The top of the side walls is provided with an outwardly projecting offset 43 running longitudinally of the conduit.

Clamps are disposed within the conduit for holding lamp receptacles in the desired position` One type of clamp is adapted to hold a lamp receptacle such as that shown in Figure 9 comprising a base portion 44 and an upper portion 45 provided with a lamp socket 46. This lamp receptacle is of conventionaldesign with the clamp. Strap 41 is further provided with a 10 threaded aperture 50 disposed centrally between,` the ends of the strap. The ends of the strap are provided with projecting shoulders I of appropriate size to be received within the offsets 43 in the top of side walls of the conduit the overall length of the strap being approximately equal to the maximum internal width of the conduit measured across the offsets at the top of the side walls thereof. The ends of the strap are bent downwardly below the shoulders 5I to provide 20 legs 52 which project downwardly toward the bottom of the conduit. 'Ihe legs 52 are of suillcient length so that outwardly extending projections 53 at the ends of the legs will be received within the longitudinal grooves 42 adjacent the 25 bottom of the conduit.

The legs 52 are provided with supporting members 54, which may with advantage be stamped out of the central portion of legs, extending from the legs adjacent their extremities upwardly and inwardly toward the base 44 of the lamp receptacle. The supporting members provide means for supporting the bottom of the receptacle base 44 and for holding the top of the receptacle base against the clamp strap 41, as shown in Figure 7.

This result is accomplished by providing the ends of supporting members 54 with lugs 55 bent inwardly on a plane substantially parallel to strap 41 in order to support the bottom of receptacle base 44, and by further providing the supporting members 54 with vertically projecting lugs 56 adapted to hold the sides of the receptacle base 44 in a stationary position.

The position of the legs 52 and supporting members 54 is such that with the clamp out of 45 the conduit, the lamp receptacle slides easilyeven somewhat loosely-into position in the clamp with the upper portion 45 of the receptacle received within cut-out portion 48 and with the bottom of receptacle base 44 resting upon 50 lugs 55. The positioning of the legs 52 and supporting members 54, however, is also such that when the legs are forced downwardly within the side walls 40 of the conduit until projections 53 engage the longitudinal grooves 42 of the con- 55 duit, thecompression of the legs 52 toward one another presses the Alugs 56 against the sides of receptacle base 54 and the upward component of this compressive movement forces the lugs 55 upwardly against the receptacle base 44, thus 6'0 holding the lamp receptacle stationary in a viselike grip.

A second type of receptacle clamp is shown in Figure 13 and is adapted to hold a conventional lamp receptacle of the type shown in Figure 14 65 comprising a base portion 51 and an upper portion 58. This lamp receptacle is constructed in conventional practice from the receptacle shown in Figure 9 by adding an additional base portion held adjacent the bottom of the smaller recep- 70 tacle (that shown in Figure 9) by av bolt 59 and held in position by the projection 59 on the bottom of receptacle base 44. The added portion of the receptacle base 51 is provided with a socket 60 adapted to receive a conventional type of 75 starting switch 6| (Figure 1b) provided with bayonet-lock contacts 62 so that the starting switch may be placed in operating position within the socket by merely inserting the contacts 62 into socket 60 and turning the switch until contacts 62 are locked in position.

The receptacle clamp shown in Figure 13 comprises a strap 63 provided with a cut-out portion 64 having sutlcient width and depth to receive the upper portion 5 6 of the lamp receptacle. Strap 63 is further provided with a circular cutout portion 65 so positioned as to permit insertion of the starting switch 6| through the strap into its socket 60 in the receptacle base 51. A threaded aperture 66 is also provided in strap 63 between the two out-out

portions

64 and 65 for a purpose hereinafter more fully described. 'I'he ends of the strap 63 terminate in shoulders 61 adapted to be held within the oisets 43 in the side walls 40 of the conduit the overall length of the strap being approximately equal to the maximum internal width of the conduit measured across the offsets at the top of the side walls thereof. The clamp is further provided with substantially U-shaped legs provided with threaded apertures 68 at the bend of the U to permit the legs to be held against the strap 63 by means of screws 69 projecting downwardly through the strap shown in Figures 12 and 13. Outer sections 10 of each leg are slightly arched inwardly at their central portions, and terminate in outwardly projecting edges 1I adapted to engage in the longitudinal internal grooves 42 of the conduit. Downwardly projecting lugs 12 at the bottom of the leg sections 10 are adapted to rest on the bottom wall 4I of the conduit. Inner sections 13 of the U-shaped legs terminate in horizontal projections 14 adapted to support the bottom of the receptacle base 51. The length of sections 13 is substantially equal to the depth of receptacle base 51, so that the lamp receptacle may be inserted easily into the cut-out portion 64 when the screws 69 are loosened. Upon tightening the screws 66, the projections 14 press upwardly against the bottom of receptacle base 51, forcing the top of the receptacle base against the underneath portion of strap 63 and simultaneously securing the U-shaped legs rmly to strap 63. The assembled lamp receptacle and clamp may then be placed in position Within the conduit by forcing it downwardly into the position shown in Figure 12. When the clamp is so placed in position, the outer leg sections 10 are squeezed together, and the inner leg sections 13 are correspondingly squeezed against the base 51 of the lamp receptacle. This effect is so pronounced that even when the screws 69 are ,not tight, and the lamp receptacle is fairly loose in the clamp before inserting lt into the conduit, the compression of the legs 10 when the clamp is forced into the conduit causes the lamp receptacle to be' gripped tightly.

The two lamp receptacle-clamp assemblies, whether they be both of the type shown in Figure 9 or one assembly as in Figure '7 and one assembly as in Figure 12, may be slid toward or away from one another with their lamp sockets facing each other until they are in the proper position to receive the two ends of a fluorescent lamp 15.

The end of the conduit where it is not desired to introduce electric conductors may be provided with an end fitting such as that shown in Figure 10. This fitting comprises an end wall 16, conforming in outline substantially to the cross-sectional shape of the conduit. The end fitting is further provided with a bottom retaining member 'll of substantially less width than end wall 16 or the bottom of the conduit. The retaining member is provided with upwardly flaring projections T8 adjacent its extremity, the projections 16 being adapted to engage the internal grooves 42 at the base of the conduit. The retaining member 1l advantageously is further provided with a longitudinal depression 80 in order to press against the bottom wall 4| of the conduit and thus impart a vertical spring tension on projections 18 (as shown in Figure ll) so as to lock them within the internal grooves 42 at the base of the conduit.

The auxiliary unit for the fluorescent lamp is placed in position within the walls of the conduit, advantageously intermediate two cooperating lamp receptacles. The auxiliary unit comprises a body portion 8| provided at the bottom thereof with projecting lips 82 which are disposed adjacent the bottom wall 4| of the conduit when the auxiliary unit is placed in position within the conduit. The auxiliary unit is held in position by a locking device comprising a strap 83 having rounded and downwardly flaring ends 84 (Figures l, 2, and 5) to permit the strap being turned, after insertion over the lip 82 of the auxiliary unit (as indicated by the dotted lines and arrow in Figure 2), to enter the internal grooves 42 at the base of the conduit. The strap 03 is provided with a threaded aperture 85 in the central portion of the strap and an additional threaded aperture 88 located between aperture 85 and one end of the strap. A setscrew 8l is inserted in one of these threaded apertures (85 or 85), and by turning the setscrew down the end of the screw presses against lip 82 of the auxiliary unit pressing the lip 82 against bottom wall 4| of the conduit and simultaneously forcing strap 83 upwardly so as to lock ends 84 of the strap within the internal grooves 42 of the conduit. The question of selecting either aperture 85 or aperture 86 for the insertion of set-screw 8l depends upon the position of the lip 82 of the auxiliary unit as well as the width of this lip across the end of the unit as will be clearly understood by one skilled in the art.

The auxiliary unit and the lamp receptacles are connected electrically as shown in Figures and 26., The wiring diagram shown in Figure 25 is that provided for lamp assemblies in which the starting switch is positioned in the base of one of each pair of cooperating lamp receptacles, and according to this circuit the fixtures are connected in series across power line 88 in the seriatim order of the auxiliary unit 8|, lamp filament 88', starting switch 6|, and lamp filament 88. The wiring diagramy shown in Figure 26 is that provided for a lamp assembly in which the starting switch is contained within the auxiliary unit, and according to this circuit the xtures are connected in an equivalent manner, the only difference being that

filaments

88 and 88" are connected in series with the starting switch terminals of auxiliary unit 8|.

After making suitable connections between the auxiliary unit and the lamp receptacles, a cover member for the conduit is snapped into place. This cover member comprises an elongated strip 89 provided along its longitudinal edges with shoulders 90 adapted to be received within the offsets 43 in side walls 40 of the conduit. The cover member, which may be supplied in various lengths, is cut to a length approximately equal to the distance between the straps of the cooperating lamp receptacle clamps.

The joint between the cover member of the conduit and the strap of an adjoining receptacle clamp is covered with a cover clamp comprising a strap 9| provided with shoulders 92 adapted to engage the outside of offsets 43 as shown in Figure 6. The strap 9| serves to hold the side walls of the conduit together and prevents the cover from becoming dislodged. If desired, additional straps 9| may be mounted midway between the lamp receptacles. The strap 9| is provided with a slot 93 (Figure 2) disposed centrally of the strap and extending transversely across the strap so as to permit alignment between this slot and the threaded

apertures

50 and 65 in the straps of the lamp receptacle clamps shown in Figures 8 and 13.

Long sections of conduit, which must sometimes be rigidly connected together to make a single unit of uniform rigidity, are connected by the fitting shown in Figures 1 4. This connector tting comprises a bottom wall 94 and side walls 95 with offsets 96 extending longitudinally of the connector along the edges of the bottom wall 94. These offsets provide shoulders which engage the longitudinal grooves 42 at the base of the conduit. Set-screws 91 project downwardly through the bottom wall 94 in engagement with threaded collars 98 raised above the surface of bottom wall 94. These collars are preferably staggered as shown inv Figures 2 and 3 and are so positioned that at least two set-screws may be screwed down against the bottom wall 4| of each of the adjoining conduits. By screwing down set-screws 91 the bottom wall 94 of the connector fitting is forced upwardly from bottom wall 4| of the conduit, thus locking the offsets 96 within the internal grooves 42 of the conduit. The side walls 95 of the connector fitting provide the necessary longitudinal rigidity for the bottom wall 94, thus insuring a rigid connection between the interconnected adjoining conduits. The interconnected conduits are secured to any substantially fiat surface by screws, or the like, inserted into the surface through knock-out holes 99 defined by suitable scorings placed at appropriate intervals in the bottom wall 4| of the conduits.

Conduits meeting at an angle may be connected to one another by means of the internal elbow shown in Figures 16 and 20, or by an external elbow such as that shown in Figure 2l, or by a flat elbow such as that shown in Figure 19. Each of these elbows comprises channelshaped legs identical in construction with the conduits, that is, the legs of the elbows are provided with longitudinal internal grooves 42 and outwardly projecting offsets 43. Interconnection between the leg of one such elbow and an adjoining conduit (or between adjoining conduits where rigidity in handling is not essential) is provided by means of the connector fitting shown in Figures 16-20. This fitting comprises a substantially flat member |00 having upwardly projecting side straps |0| of sufficient width to overlap substantially the interior of side walls 40 of adjoining conduits, and of height not in excess of the height of the side walls 40 up to the offsets 43. The edges |02 of the fiat member |00 adjoining the side straps |0| project beyond the plane of the side straps and flare upwardly so as to engage the longitudinal internal grooves 42 at the base of the conduit. Thus, the overall width of the connector fitting is approximately equal to apertures the maximur'n'internal width of the conduit measured across the internal grooves at thebasev of the conduit.- The flat member |is further provided with longitudinal upwardly-projecting ridges |03-ln order to impart additional rigidity to the flat member to prevent flexing of the member along its longitudinal axis. lThe flat member |00 is further provided with a somewhat downwardly projecting tongue |04 disposed along the longitudinal axis of member |00 with the end of the tongue terminating at approximately the midpoint of this axis. The tongue is preferably stamped out of flat member |00 as shown in Figures 19-`21. 'I'he tongue |04 serves as a stop when the end of flat member |00 towards which the tongue points is inserted in place along the bottom wall 4| of the conduit, as shown in Figure 16. AWhen the free end of the connector fitting is inserted in place in an adjoining conduit, tongue |04 is sprung upwardly thereby permitting insertion of the flat member |00 the full distance up to its center point within the adjoining conduit. 'I'his connector fitting is thus provided with means for insuring equally rigid connection with each of the two abutting ends of adjoining conduits as well as complete covering of the joint between these abutting ends. Cover members for the internal elbows shown in Figures 16 and 20 are provided by cutting a slot (as by a saw) at in the shoulders |06 of a flat cover member, as shown in Figure 22. The cover member is then bent as indicated by the arrowY in Figure 22 into the position indicated by the dotted lines. A cover member is similarly provided for the external elbow shown in Figure `2l by cutting a relatively wide groove |01 in the shoulders |06 of the flat cover member as shown in Figure 23, and by then bending the cover member into the position indicated by the dotted lines in this figure.

Electric conductors may be introduced into the conduit either through knock-out portions |08 defined by appropriate scorings ln the bottom wall 4| of the conduit, as shown in Figure 37, or through appropriate knock-out portions in an end fitting such as shown in Figure 38. In either event the cable ||0 carrying the conductors are inserted through the knock-out portions and are held in place by a lock nut ||2 withinl the interior of the conduit.

The end admission of wires into the end of the conduit is shown in greater detail in Figures 27-29. This end fitting comprises an end wall |3 conforming substantially to the cross-sectional shape of the conduit and being provided with scorings defining knock-out portionsA H4 adapted to fit various standard sizes of electric conductor cables. The end fitting is further provided with a cover wall ||5 projecting from the top of the end wall I|3 with the sides of the cover wall bent inwardly to provide shoulders ||6 adapted to engage the interior of projecting offsets 43 of the conduit. The fitting is further provided with a bottom wall ||1 ,projecting from the bottom of end wall ||3 and of a width approximately equal to the maximum internal width of the conduit measured across the internal grooves at the base of the conduit. The edges of bottom wall ||1 terminate in upwardly flaring edges ||8 adapted to engage the longitudinal internal grooves 42 at the base of the conduit.. The cover wall and the bottom wall of the fitting are provided with aligned apertures with the apertures in the bottomwall |1 being threaded so that screws |20 projecting through the apertures in the cover wall ||5 may engage in the fitting shown in Figure 38 providing for in bottom wall H0. When the screws |20 are turned downwardly, they press against the bottom wall 4| of the conduit and simultaneously 1 force the bottom wall I1 and its projecting edges ||8 upwardly to lock the edges H0 within the internal grooves 42 at the base of the conduit. The junction between the cover wall of the end fitting and the cover member 88 of the conduit may be covered with acover strapsuh as that described above and shown in Figure 6.

The lamp reflector |2| shown in Figure 1 comprises an elongated trough-shaped member having a light-reflecting interior surface. A particularly advantageous form of such reflector is that shown in cross-section in Figures l and 12 and in plan view in Figure 36, this reflector having a substantially parabolic cross-section. The ends of the reflector` are 4provided with a plurality of knock-out portions |22 defined by suitable scores flector may be placed in any one of a pluralityv of positions with the ends of the reflector engaging the upper portion 45 (or 58, or both as the case may be) of cooperating lamp receptacles. This result is obtained by making the scorfngs defining the knock-out portions of sufficient depth to receive the upper portion of the lamp receptacles and of a width equal to one-half the width of the upper portion of the lamp receptacles. By providing a plurality (say, six) of such knock-out portions immediately adjacent one another it is possible to install the reflector in position and in engagement with two cooperating lamp receptacles with its plane of symmetry either ina vertical position relatively to the channel cover or about 221/; or 45 from the vertical, thus providing for distribution of light as desired on the articles to be illuminated. It will be notedthat Y with knock-out slots |23 so placed within the body of the reflector near the knock-out portions |22 as to be aligned with threaded

apertures

50 and 66 in the lamp receptacle clamps shown in Figures 8 and 13, respectively. After the reflector is placed in the desired position, screws |24 are inserted (Figures l, 'I and 12) through the4 slots |23 in each end of the reflector, through the slot 03v in the cover clamp 9|, and into engagement with the threaded

aperture

50, or 66, as the case may be, in the lamp receptacle clamps. ln this manner the reflector ls firmly held in position in engagement with the lamp receptacle clamps. The reflector may also be provided interiorly of the knock-out slots |23 at one end of the reflector with overlapping circular knock-out portions |25 so placed as to permit removal of an appropriate knock-out portion which will receive the top of starting switchvSl if` a lamp receptacle such as that shown in Figure 14 is used in the lamp assembly.

The longitudinal edges of the reflector |2| are further provided with rolled edges |26 which impart additional strength to the reflector, and also facilitate interconnection of adjacent connectors as well as the attachment of end pieces, as is hereinafter more fully described.

A modified form of lamp reflector is shown in Figure 30 and comprises a trough-shaped member |21 having a substantially flat bottom section as shown in Figure 32. This type of reflector is provided with knock-out portions |28 in the flat portion of the reflector and on one side of the reflector with both knock-out portions disposed adjacent the ends of the reflector. The reflectors are further provided with small knock-out slots |3D to permit the attachment of the reflector to the assembly by screws |24 (Figure 1), and with large knock-out holes |3| adjacent one end of the reflector interiorly or slots |30. The knock-out portions 3| are of suitable size and are appropriately placed to receive the starting switch 6| when a lamp receptable such as that shown in Figure 14 is used in the lamp assembly. By providing this type of reflector with knock-out portions in the bottom section and on only' one side of the reflector it will be apparent that the reflector may be installed with itsplane of symmetry in a vertical position relatively to the conduit cover, or in a position tilted away from the vertical in either direction by merely turning the reflector so that the appropriate knock-out portions will be in the proper location. The longitudinal edges of the reflector are also provided with rolled edges |26 asin reflectors |2|.

Both types of reflectors (|2| and |21) may be attached to another reflector of similar shape by means of the connecting member |32 (Figures 30 and 33). This connecting member is provided with the same cross-sectional shape as the particular reflector with which it is to be used, and in the drawings the connecting member is shown with a shape conforming to that of reflector |21. The sides and bottom of this type of connecting member are provided with knock-out portions |33 of sufficient width to receive the upper portion of a lamp receptacle, and are of a depth at least twice that of the thickness of the upper portion of a lamp receptacle. With this construction adjacent lamp reflectors may be placed in position around fluorescent lamps 15 as shown in Figure 24. 'Ihe ends of adjacent reflectors engage the upper portions 45 (or 45 and 58, as the case may be) of adjacent receptacles mounted back to back, and the connecting mem- |32 is slid along the interior of one reflector until the appropriate knock-out portion |33 engages both of the upper portions 45 (or 45 and 58) of the adjacent lamp receptacles. The rolled edges |34 along the side edges of the connecting member |32 are smaller than the rolled edges |26 of reflectors |2| and |21 so that the smaller rolled edges |34 can enter the interior of rolled edges |26 as shown in Figure 31.. This cooperation between the rolled edges of the connecting member and of the reflectors provides rm interconnection of adjacent reflectors, maintains the reflector in alignment, and closes any gap between them. Connecting member 32 is further provided with knock-out slots |35 to permit insertion of the screw |24 through the connecting strap.

The reflectors may be provided with end pieces comprising an end wall |36 conforming in shape to the cross-sectional shape of the interior of the reflector with which it is to be used, the end piece shown in Figure 35 being one for use with reflector |21 (Figure 30). The sides and bottom of the end wall |36 are provided with a projecting edge |31 adapted to fit into the end of the re- 75 flector. This projecting edge |31 is provided with cut-out portions |38 of a. width sufficient to receive the upper portion of a lamp receptacle so that the reflector end piece covers the back of the upper portion of a lamp receptacle a: shown in Figures 1 and 24. Lugs |40 are provided at the top side edges of the end wall |36, and are formed with apertures |4| in alignment with the rolled edges |26 of the reflectors. The reflector end piece may be secured in position at the end of the reflector by means of conventional self-tapping screw |42 inserted through aperture 4| and engaging the interior of the rolled reflector edges |26.

It will be seen that the lamp assembly of the invention comprises a unitary structure composed of relatively simple parts which permit the installation of fluorescent lamps in substantially any desired position within a show window, or the like, and that the assembly is such as to permit proper distribution of the light given of! by the fluorescent lamp. Additional flexibility is imparted to the lamp assembly by the novel receptacle clamps and other elements of our lamp assembly which permit a relatively small but highly important movement of the lamp receptacles toward or away from one another to accommodate replacement lamps which vary slightly in their overall length. The lamp assembly of our invention may be assembled readily in a very short time and provides easy accessibility to all portions of the assembly, such as starting switches and auxiliary units, which may have to be replaced due to mechanical or electrical failure. The various parts of our novel lamp assembly may be made inexpensively and may be stamped from standard metals of various types depending essentially upon, the part to be produced. The entire lamp assembly is attached etiher directly or indirectly to the conduit so that the only part of the assembly which must be attached directly to a plane surface such as a wall, ceiling, or the like, is the conduit thus eliminating the necessity, as in conventional practice heretofore, of accurately spaced drilled holes.

We claim:

1. Apparatus of the character described comprising a clamp for a lamp receptacle having a base and also an upper portion provided with a lamp socket, said clamp comprising a strap provided with a cut-out portion adapted to engage the receptacle above the base thereof, legs projecting from the ends of the strap to a level below the base of the receptacle, and means associated with said legs for engaging the bottom of the receptacle base and adapted to hold the top of the receptacle base against the strap.

2. Apparatus of the character described comprising a clamp for a lamp receptacle having a base and a portion of reduced size immediately above the base, said clamp comprising a strap provided with a cut-out portion of suitable size and shape to receive the reduced portion of the lamp receptacle, legs projecting from the ends of the strap to a level below the base of the receptacle, and means connected to said legs and configured so as to be adapted to engage the undersurface of the receptacle base and hold the receptacle in firm engagement with the strap.

3. Apparatus of the character described comprising a clamp for a lamp receptacle having a base and also an upper portion provided with a lamp socket, said clamp comprising a strap provided with a cut-out portion adapted to receive the receptacle above the base thereof, legs projecting downwardly from the ends of the strap to a level below the base of the receptacle, and supporting members extending from the legs adjacent the bottom thereof upwardly and inwardly in such manner as to be adapted to engage the base of the receptacle for supporting the bottom of the receptacle base and for holding the top of the receptacle base against the strap.

4. Apparatus of the character described comprising a clamp adapted for mounting in a U-shaped conduit a lamp receptacle having an upper portion of substantially rectangular crossseotion provided with a lamp socket and having a base of substantially greater cross-sectional area, said clamp lcomprising a strap of a width about equal to the width of the conduit provided with a cut-out portion adapted to engage the upper portion of the receptacle adjacent the base thereof, legs projecting downwardly from the ends of the strap to a level below the base of the receptacle, and means connected with said legs adapted to engage the bottom of 'the receptacle base, said means being so arranged that when the clamp legs are squeezed together for insertion into lthe conduit the receptacle base is rmly pressed between said members and the clamp strap.

5. Apparatus of the character described comprising a clamp for a lamp receptacle having a base and also an upper portion of reduced size provided with a lamp socket, said clamp cornprising a strap provided with a cut-out portion adapted to receive the receptacle above the base portion thereof, legs projecting downwardly from the ends of the strap to a level below the base of the receptacle, and supporting members connected to said legs adjacent the bottom thereof and extending upwardly and inwardly therefrom, said members terminating in a plurality of lugs arranged and positioned so as to be adapted to support the bottom of the receptacle base and for holding the top of the receptacle base against the strap.

6. Apparatus of the character described comprising a clamp for a lamp receptacle having a base provided with a starting switch and also having an upper portion of reduced size provided with a lamp socket, said clamp comprising a strap provided with a cut-out portion adapted to receive the reduced portion of the receptacle above the base thereof and further provided with a 'cut-out portion adapted to permit projection of the starting switch through the strap, legs projecting downwardly from the ends of the strap to a level below the base of lthe receptacle, and means associated with said legs for supporting the bottom of the receptacle base in a stationary position and for holding the top of the receptacle base against the strap.

7. Apparatus of the character described comprising a clamp for a lamp receptacle having a base and also having an uppe'r portion of reduced size provided with a lamp socket, said clamp comprising a strap provided with a cut-out portion adapted to receive the receptacle above the base thereof, substantially U-shaped legs projecting downwardly from the ends of the strap to a level below the base of the receptacle, said legs being secured to the strap at the bend in the U, and means associated with the inner downwardly extending portion of each leg for supporting the bottom of the receptacle and for holding the top of the receptacle base against the strap.

8. Apparatus of the character described 'comprising a clamp for a lamp receptacle having a base and an upper portion of reduced size provided with a lamp socket, said clamp comprising a strap provided with a cut-out portion adapted to receive the receptacle above the base thereof, substantially U-shaped legs each having an inner portion and an outer portion projecting downwardly from the ends of the strap to a level below the base of the receptacle, each of said legs being secured at the bend in the U to the strap by means of a leg screw, and inwardly projecting lugs formed at lthe bottom edge of the inner portion of each leg and adapted to receive and support the bottom of the receptacle base, said lugs being so positioned that upon tightening the leg screw with a lamp receptacle positioned in the clamp the base of said receptacle is supported by the lugs and pressed upwardly into firm engagement with the strap.

9. A fluorescent lamp assembly of the character described comprising a channel-shaped conduit of generally rectangular cross-section having side walls and a bottom wall, each of the side walls being provided with a relatively narrow in-ternal groove running longitudinally of the conduit adjacent the bottom wall thereof, a pair of lamp receptacles positioned in said conduit, clamp means securing each lamp receptacle' in the conduit, a fluorescent lamp mounted in said lamp receptacles, a fluorescent lamp auxiliary unit comprising a body portion provided with a lip mounted in the conduit with said lip adjacent the bottom wall of the conduit, locking means for securing said auxiliary unit in the conduit comprising a strap of a length approximately equal to the width of the conduit across the grooves in the side walls thereof, said strap having rounded ends permitting it to be turned transversely of the conduit and into the grooves after insertion over the lip of the auxiliary unit, and means connected to said strap for engaging the lip of the auxiliary-unit and holding the auxiliary unit in position in the conduit, and wires positioned in the channel and operatively connecting the fluorescent lamp through the lamp receptacles and the auxiliary unit with a sourcel of electric current.

10. In apparatus of the character described, a clamp for,k locking a fluorescent lamp auxiliary unit having a projecting lip in a channel shaped conduit having side walls and a bottom wall and with each of said side walls being provided with a relatively narrow inturned groove running longitudinally of the conduit, said clamp comprising a strap approximately equal in length to the interior width of the conduit across the grooves in the side walls thereof, said strap being formed with ends sufilciently rounded to permit it to be turned transversely of the conduit and into the grooves after insertion over the projecting lip oi' the auxiliary unit, and means connected with said strap and adapted to engage the lip of the auxiliary unit in a manner to l? ld the auxiliary unit in position in the conduit.

11. A fluorescent lamp assembly of the character described comprising a channel-shaped conduit of generally rectangular cross-section having side walls and a bottom wall, each of the side walls being provided with a relatively narrow internal groove running longitudinally of the conduit adjacent the bottom wall thereof, a lamp receptacle positioned in said conduit immediately adjacent the end thereof, clamp means securing said lamp receptacle in the conduit comprising a receptacle-engaging strap extending transversely of the conduit at the end thereof and legs extending downwardly from the ends of said strap within the confines of the'channel and engaging in the grooves in the conduit side walls adjacent the bottom wall, a closure for the end of the conduit comprising a closure member conforming in outline to the cross-sectional shape of the conduit abutting against the end of the conduit, a bottom wall retaining member connected to said closure member' and extending into the conduit adjacent the bottom thereof, the side edges of said retaining member being spaced inwardly from the legs of the receptacle clamp, and projections extending laterally from said retaining member at the free end thereof and engaging in the grooves in the conduit side walls inwardly of the receptacle clamp legs in a manner to hold the closure member in place, a second fiuorescent lamp receptacle mounted in the conduit, a fluorescent lamp mounted in said receptacles, and means operatively connecting said lamp with a source of electric current.

12. In apparatus of the character described, an end closure for a channel-shaped conduit having side walls and a bottom wall in which a lamp receptacle is mounted at the end thereof by means of a clamp comprising a strap extending transversely of the conduit at the end thereof and legs extending downwardly from the strap within but adjacent the conduit side walls, said end closure comprising a closure member conforming in outline to the cross-sectional shape of the conduit and adapted to abut the end of the conduit, a bottom wall retaining member connected to said closure member and adapted to extend into the conduit adjacent the bottom wail thereof, said retaining member being substantially narrower than the closure member so as to be adapted to lie in the conduit with its side edges spaced inwardly from the side walls of the channel and from the legs of the receptacle clamp, and projections extending laterally from said retaining meiber at the free end thereof and adapted to engage the side walls of the conduit inwardly of the receptacle clamp legs in a manner to hold the closure member in the conduit,

13. A fluorescent lamp assembly of the character described comprising a channel-shaped conduit having side walls and a bottom wall, said side walls being formed with grooves running longitudinally of the conduit adjacent the bottom wall thereof, a pair of lamp receptacles mounted in said conduit, a fluorescent lamp mounted in said lamp receptacles, means for admitting wires to said conduit for connection to the lamp receptacles comprising an end fitting including an end portion closing the end of the conduit, said end portion being formed with a knock-out opening adapted to permit the passage of wires, a bottom portion connected to said end portion and extending into the grooves in the conduit side Walls adjacent the bottom wall, threaded apertures being formed in said bottom portion, a cover portion also connected to the fitting end portion and forming a cover for the conduit at the end thereof, said cover portion being formed with apertures aligned with the apertures in the bottom portion, and screws extending through the apertures in the cover portion engaging in the threaded apertures in the bottom portion and pressing against the conduit bottom wall to force the bottom portion of the fitting into tight engagement in the grooves in the conduit side walls, and wires entering the channel through the knock-out opening in the fitting end portion and operatively connected with the fluorescent lamp.

14. In apparatus of the character described, an end fitting adapted to permit wires to enter the end of a conduit having side walls and a bottom wall and having the side walls formed with grooves running longitudinally of the conduit adjacent the bottom wall thereof, said fitting comprising an end portion adapted to close the end of the conduit, said end portion being formed with a knock-out portion adapted to be removed to permit the passage of wires therethrough, a bottom portion connected to said end portion adapted to extend into the grooves in the conduit side walls adjacent the bottom wall, threaded apertures being formed in said bottom portion, a cover portion also connected to the fitting end portion and adapted to form a cover for the conduit at the end thereof, said cover portion being formed with apertures aligned with the apertures in the bottom portions, and screws extending through the apertures in the cover portion engaging in the threaded apertures in the bottom portion and adapted to press against the conduit bottom wall in a manner to force the bottom portion of the fitting into tight engagement in the grooves in the conduit side Walls.

15. Apparatus of the character described comprising a clamp for an electrical tting having a. base portion, said clamp comprising a strap adapted to engage the top of the fitting base portion, legs projecting from the ends of the strap to a level below the fitting base portion, and means associated with said legs for engaging the bottom of the fitting base portion and adapted to hold the top of the fitting base portion against the strap.

CHARLES E. RUTHERFORD. ARTHUR O. LA DUCER. ROBERT H. MURPHY.