Patent Publication Number: US-10323834-B2

Title: Rotable light assembly for an electronics rack

Description:
FIELD OF THE INVENTION 
     The present invention relates to a light assembly and, more particularly, to a rotatable light assembly for mounting to an electronics rack. 
     BACKGROUND 
     Electronics equipment, such as audio visual components and computer servers, are in many cases housed on racks designed to store and protect the equipment. Typically such racks are dimly lit, if lit at all, making maintenance of the equipment difficult. Maintenance personnel generally have to rely upon overhead lighting or portable flashlights to provide illumination. 
     Generally existing lighting is fixed in the direction of illumination, which could result in poor illumination, or even shadows being cast on the equipment making maintenance and inspection difficult. 
     A need, therefore, exists for an improved light assembly that permits orientation of a light fixture. 
     SUMMARY OF THE INVENTION 
     A light assembly for an electronics rack that includes a light fixture with a housing within which is mounted a light source, a cover mounted over the light source, and a rotatable mounting assembly for attaching the light fixture to an electronics rack. The mounting assembly includes at least one base that has a mounting flange adapted to be secured to the electronics rack. A support cradle is attached to the mounting flange and has an inner race with a curved surface defined by a radial axis. The inner race has a plurality of teeth formed on at least a portion of the curved surface. The teeth project radially inward. A stanchion is mounted to the flange adjacent to the cradle and has an axle extending laterally outward therefrom over the cradle. The axle has a center axis that is coaxial with the radial axis of the inner race. 
     At least one light mount is attached to the base. The light mount includes a fixture bracket that is removably attached to a portion of the light fixture. The light mount includes a mount frame with an outer race that has a curved surface, and a center hub with a hub axis that is coaxial with the radial axis of the outer race. The hub is rotatably mounted to the axle with the hub axis coaxial with the axle axis such that rotation of the mount frame causes the outer race to rotate relative to the inner race. 
     Preferably the light housing is an elongated housing and the light source is a strip of light emitting diodes. 
     In an embodiment the flange includes a plurality of notches that are sized to received screws for attaching to holes in the electronics rack for securing the base to the rack. 
     In an embodiment, the cradle includes at least one retention tab, and wherein the curved surface of the outer race has at least one notch formed in the surface of the outer race and adapted to permit passage of the retention tab, the mount frame being locked onto the axle by the retention tab. Optionally, the mount frame, and thus the light mount, is removable from the axle when the notch is aligned with the retention tab. In an embodiment, there are two retention tabs attached to the cradle at spaced apart locations on the opposite side of the cradle from the stanchion, and wherein there are two notches formed in the surface of outer race, the two notches are located so as to align with the two retention tabs. 
     Preferably the outer race includes a ratchet tooth that projects radially outward from the curved surface of the outer race so as to contact the teeth on the inner race and thereby provide ratcheting engagement. 
     In an embodiment, the hub axis is parallel to a longitudinal axis of the channel of the light mount. 
     The fixture bracket may include an open channel with two retaining lips, the channel configured to slidingly receive an end of housing of the light fixture. 
     In an embodiment, the mounting assembly includes two bases and two light mounts, where one base and light mount combination is attached to each end of the light fixture, and wherein the hub axes of the light mounts are coaxial with one another. 
     The foregoing and other features of the invention and advantages of the present invention will become more apparent in light of the following detailed description of the preferred embodiments, as illustrated in the accompanying figures. As will be realized, the invention is capable of modifications in various respects, all without departing from the invention. Accordingly, the drawings and the description are to be regarded as illustrative in nature, and not as restrictive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For the purpose of illustrating the invention, the drawings show a form of the invention which is presently preferred. However, it should be understood that this invention is not limited to the precise arrangements and instrumentalities shown in the drawings. 
         FIG. 1  is a perspective view of a rotatable rack mountable light assembly according to an embodiment of the invention with the light fixture rotated in one orientation. 
         FIG. 2  is a perspective view of the rack mountable light assembly of  FIG. 1  with the light fixture rotated into another orientation. 
         FIG. 3  is an enlarged perspective view of one end of the light assembly of  FIG. 1  with the mounting assembly shown separated. 
         FIG. 4  is an end view of the light assembly of  FIG. 2 . 
         FIG. 5  is an end view of the light assembly of  FIG. 1 . 
         FIG. 6  is an enlarged perspective view of one end of the light assembly of  FIG. 1  with the mounting assembly shown assembled. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the figures, a light assembly  10  is shown for mounting to an electronics rack. The light assembly  10  includes a light fixture  12 , with a housing  14  within which are mounted a light source (not shown), such as a strip of light emitting diodes (LEDs). A translucent or transparent cover  16  is mounted over the light source. A power source (not shown), such as a conventional A/C supply or an internally mounted battery supply, provides power to the light source. A switch  18  controls operation of the light source. The details of the light fixture  12  and its operation are conventional and, thus, no further discussion is necessary. 
     The light fixture is removably attached to a rotatable mounting assembly  20 . The mounting assembly  20  includes at least one base  22 , and at least one light mount  24  that attaches to the light fixture  12 . The base  22  includes a mounting flange  26  that is adapted to be secured to an electronics rack. In the illustrated embodiment, the flange  26  includes a plurality of notches  28  that are sized to received screws for attaching to holes in the electronics rack to secure the base  22  to the rack. The base  22  also includes a support cradle  30  that is fixed or otherwise attached to the flange  26  and includes an inner race  32  with a curved surface that is preferably semi-circular in shape with a radial axis IA. The inner race  32  preferably has a plurality of teeth  34  formed on at least a portion of the surface of the inner race. 
     An axle  36  is mounted to and extends laterally outward from a stanchion  38  that is mounted adjacent to the cradle  30 . The axle  36  has a center axis A that is coaxial with the radial axis IA of the inner race  32 . The axle  36  preferably includes one or more resilient legs  40  that are cantilevered off of the stanchion  38 . In the illustrated embodiment, there are four legs  40 . The cradle  30  also optionally has at least one retention tab  42 . More preferably, there are two retention tabs  42  attached to the cradle at spaced apart locations on the opposite side of the cradle  30  from the stanchion  48 . 
     The light mount  24  includes a fixture bracket  44  that removably attaches to a portion of the light fixture  12 . In the illustrated embodiment, the fixture bracket  44  includes an open channel  46  with two retaining lips  48 . The channel  46  is configured to slidingly receive an end of housing  14  so that the retaining lips  48  prevent removal. A screw or bolt  50  could be used to secure the housing  14  to the fixture bracket  44 . 
     The light mount  24  also includes a mount frame  52  with an outer race  54  that has a curved surface, preferably at least semi-circular in shape and more preferably slightly greater than semi-circular with a radial axis OA. The outer race  54  optionally has at least one, and more preferably two notches  56  formed in the surface of outer race. The notches  56  are located and sized to receive the retention tabs  42  of the cradle  30 . The outer race  54  optionally includes a ratchet tooth  58  that projects radially outward from the outer race  54 . The mount frame  52  includes a center hub  60  that has a hub axis HA that is coaxial with the radial axis OA of the outer race  54 . The hub axis HA is also preferably parallel to the longitudinal axis of the channel  46  of the light mount  24  such that rotation of the hub axis HA causes the channel, and thus the light fixture, to rotate about the hub axis HA. 
     The light mount  24  is rotatably mounted to the base  22  as shown in  FIG. 6 . More specifically, the hub  60  is mounted to the axle  36  with the legs  40  of the axle  36  extending through the hub  60 , thus locating the hub axis HA coaxial with the axle axis A. As such, rotation of the mount frame  52  causes the outer race  54  to rotate relative to the inner race  32 . The ratchet tooth  58  is sized so as to extend outward a sufficient distance from the outer race  54  so that it contacts the teeth  34  on the inner race  32 , thereby providing a ratcheting engagement. The ratcheting engagement permits the fixture bracket  44  (and, thus, the light fixture  12 ) to be resiliently held at different angular positions as it rotates about the hub axis HA. It should be readily apparent to those skilled in the art that other forms of engagement between the outer race and the inner race can be used, such as a frictional engagement. Also, the axle  36  and hub  60  could be reversed such that the hub is mounted to the stanchion and the axle is mounted to the light mount. 
     As noted above, the legs  40  of the axle are flexible and cantilevered off the stanchion  38 . Thus as the hub  60  is slid onto the axle  36 , the legs  40  flex. Barbs  41  may be formed on the distal ends of the legs  40  to lock the hub  60  onto the axle  36 . The mount frame  52  is locked onto the axle  36  by the retention tabs  42  as shown in  FIG. 6 . In order to mount the mount frame  52  on the axle  36 , the mount frame is positioned so that the notches  56  align with the retention tabs  42  as shown in  FIG. 5 , The mount frame  52  is then slid onto the axle until it passes the retention tabs  42 . At that point, rotation of the mount frame  52  will move the notches  56  out of alignment with the tabs  42 , thus preventing removal of the mount frame off the axle  36  (see  FIG. 6 ). 
     In the illustrated embodiment, the mounting assembly  20  includes a base  22  and a light mount  24  at either end of the light fixture  12  with the hub axes HA of the light mounts being coaxial. When the bases  22  are secured to an electronics rack, the configuration of the bases and light mounts permits angular rotation of the light fixture so as to orient the light in the desired direction. See, for example,  FIGS. 1 and 2  which show two alternate angular positions of the light fixture. The channels in the light mounts allow for the spacing of the bases to be adjusted. Also, the configuration of the mounting assembly is such that it can be mounted horizontally or vertically. 
     For the purposes of promoting an understanding of the principles of the invention, reference has been made to embodiments illustrated in the drawings, and specific language has been used to describe these embodiments. However, no limitation of the scope of the invention is intended by this specific language, and the invention should be construed to encompass all embodiments that would normally occur to one of ordinary skill in the art.