Abstract:
A cabinet for mounting electronic equipment having power input port mounted external to the frame of the cabinet in order to make installation of a power input unit more convenient. The power input port may be mounted on the bottom of the cabinet whereby the power input unit, for example, a power distribution unit, may be installed prior to, during, or after installation of the cabinet. In addition, among other things, the mounting of a power input unit outside the frame of the cabinet provides for improved accessability and servicing of the power input unit and provides for more usable space inside the cabinet frame.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 60/291,117, entitled “Electronic Instrument Mounting Rack” filed May 15, 2001, the disclosure of which is incorporated by reference herein in its entirety. 
     This application contains subject matter which is related to the subject matter of the following applications, which is assigned to the same assignee as this application and was filed on the same day as this application. The below-listed applications are hereby incorporated by reference in their entirety: 
     “Method of Attaching Supports to an Electronic Equipment Cabinet”, U.S. Ser. No. 10/145,844. 
     “Support Member Having a Recess for Routing Cables and Method of Routing Cables in an Electronic Equipment Cabinet”, U.S. Ser. No. 10/145,157. 
     “A Trim Piece, a Trim Piece Mounting Arrangement and a Method of Mounting a Trim Piece for an Electronic Equipment Cabinet”, U.S. Ser. No. 10/145,846. 
    
    
     TECHNICAL FIELD 
     This invention relates generally to apparatus and methods used for mounting electronic equipment. Specifically, the present invention provides improved methods and apparatus for mounting electronic equipment in a cabinet, supplying power to the equipment, and supporting the housing, and routing electrical conduit within the housing. 
     BACKGROUND OF THE INVENTION 
     In the electronics industry, electronic equipment is typically mounted in enclosures or cabinets to facilitate installation, interfacing with related equipment, and to facilitate access by technicians for servicing and repair. One recognized standard enclosure used by electronic equipment manufacturers is the 19-inch standard for mounting electronic equipment or sub chassis into an enclosure. The 19-inch enclosure standard is defined by the Electronics Industries Association standard EIA310. The EIA310 standard, which is incorporated by reference herein, defines the specifications for the mounting of 19-inch panels and equipment. In compliance with this standard, electronic equipment manufacturers provide products, for example, computers or computer peripheral equipment, that are mountable or installable into 19-inch enclosures, cabinets, or racks, as they are referred to in the art. 
     Conventional electronic equipment racks include some form of frame or support structure upon which the equipment is mounted, typically by mechanical fasteners. This frame provides the structural support of the equipment while providing access to electrical conduit, that is, wires and cables, for power and data transfer. Panels, typically sheet metal or plastic are typically mounted to the frame to protect the equipment and to provide an aesthetically pleasing appearance to the cabinet. 
     Conventional cabinets or racks typically include some form of casters mounted on the bottom of the cabinet for facilitating installation, removal, and servicing of the equipment mounted in the rack. Conventional cabinets may also include some form of seismic support for preventing vibration damage to the equipment or toppling of the cabinets during an earthquake. In conventional equipment racks, casters and seismic supports are typically mounted to a sheet metal plate secured to the bottom of the cabinet. However, the mounting of the casters and seismic supports to the thin sheet metal of the cabinet is somewhat prone to damaging the sheet metal or failure of the caster or support during transport, handling, or vibration loading (for example, an earthquake). There is a need in the art to provide improved structural stiffness and strength to the mounting of casters and seismic supports to cabinets holding electronic equipment. 
     As would be expected, electronic equipment cabinets typically also contain numerous electrical conduits, that is, wires and cables, for power and data transfer. However, depending upon the equipment in the cabinet the number of conduits may be quite numerous and unwieldy. The presence of many exposed conduits, even when properly secured, can interfere with the installation and servicing of the cabinet as well as be prone to damage during installation and servicing. There is a need in the art to provide electronic equipment cabinets in which such cabling can be secured and possibly hidden to facilitate installation and servicing. 
     One electronic component that is typically installed in conventional electronic equipment cabinets is a power input unit, that is, the unit or component that receives electric power from an external source, such as a power outlet, and through which power is provided to the equipment in the cabinet. The power input unit may include some form of power conditioning if necessary. In conventional electronic equipment cabinets, the power input unit is typically located within the cabinet, that is, behind a panel or sheet metal barrier and thus not readily accessible to the operator or technician. Thus, in order to access the power input unit, a panel or barrier must be removed. This can be inconvenient when attempting to install, service, or simply access the power input unit. In addition, locating the power input unit within the envelope of the cabinet can consume valuable space within the cabinet that could be used for other equipment. There is also a need in the art to facilitate access to the power input unit of an electronic equipment cabinet, or to more advantageously use the space within the equipment cabinet. 
     These and other deficiencies of the prior art equipment cabinets are addressed by the present invention. 
     SUMMARY OF THE INVENTION 
     The present invention provides methods and apparatus which address many of the limitations of prior art methods and apparatus. One aspect of the invention is a cabinet for mounting electronic equipment comprising a rectangular cylindrical frame having a top, a bottom, and sides, and means for supporting the cabinet, the frame comprising vertical support members and horizontal support members, wherein the means for supporting the cabinet are mounted to at least one of the horizontal support members. 
     In one aspect of the invention, the at least one of the horizontal support members is located adjacent the bottom of the cabinet and the means for supporting the cabinet are mounted to at least one of the horizontal support members located adjacent the bottom of the housing. In another aspect of the invention, the means for supporting the cabinet comprises one at least one caster, at least one seismic support, or a combination of at least one caster and at least one seismic support. In one aspect of the invention, the means for supporting the cabinet comprises a plurality of casters or a plurality of seismic supports. 
     Another aspect of the invention is a cabinet for mounting electronic equipment comprising a rectangular cylindrical frame having a top, a bottom, sides, and casters for supporting the housing, the frame comprising vertical support members and horizontal support members, wherein the casters are mounted directly to at least one of the horizontal support members. The casters are typically mounted to one of the horizontal support members located at the bottom of the housing. 
     Another aspect of the present invention is a cabinet for mounting electronic equipment comprising a rectangular cylindrical frame having a top, a bottom, sides, and at least one seismic support for supporting the housing and minimizing the vibration load on the equipment, the frame comprising vertical support members and horizontal support members, wherein the at least one seismic support is mounted directly to at least one of the horizontal support members. Typically, the at least one seismic support is mounted to one of the horizontal support members located at the bottom of the housing. 
     Another aspect of the invention is a method for supporting an electronic equipment cabinet, the cabinet having a frame comprising at least one horizontal member, the method comprising: providing means for supporting the cabinet; and mounting the means for supporting the cabinet to the at least one horizontal member of the frame. In one aspect of this invention, providing means for supporting the cabinet comprises providing at least one of at least one caster and at least one seismic support. In another aspect of this invention, the electronic equipment cabinet has a top and a bottom and the frame comprises at least one horizontal member positioned adjacent the bottom of the cabinet, wherein mounting the means for supporting the cabinet comprises mounting the means for supporting the cabinet to the at least one horizontal member positioned adjacent the bottom of the cabinet. 
     A further aspect of the invention is a supporting arrangement for an electronic equipment cabinet, the cabinet comprising a cylindrical frame having a top and a bottom, at least one panel mounted to the frame, and at least one leveling device, the frame comprising vertical support members and horizontal support members, wherein the support arrangement comprises a supporting element mounted to a horizontal support member positioned adjacent the bottom of the frame. In one aspect of the invention, the supporting element comprises at least one caster. In another aspect of the invention, the supporting element comprises at least one seismic support. In one aspect of the invention, the frame comprises at least one L-shaped support member having a horizontal leg and a vertical leg. In another aspect of the invention, the supporting element comprises at least one caster or at least one seismic support mounted to the horizontal leg of the L-shaped support member. 
     Another aspect of the invention is a cabinet for mounting electronic equipment comprising a rectangular cylindrical frame having a top, bottom, and sides, the frame comprising vertical support members and horizontal support members, wherein at least one of the support members comprises at least one recess for installing electrical conduit, for example, electrical wires and electrical cables and the like. In one aspect of the invention, the at least one recess in the at least one support member comprises a longitudinal recess. In another aspect of the invention, the vertical support members comprise at least one vertical support member having a first recess and the horizontal support members comprise at least one horizontal support member having a second recess, wherein the first and second recesses communicate with each other. In another aspect of the invention, the frame further comprises at least one support member connecting element and wherein the first and second recesses communicate with each other via the at least one support member connecting element. 
     Another aspect of the invention is a method for routing at least one electrical conduit in an electronic equipment cabinet, the cabinet comprising a frame comprising at least one horizontal or vertical member having a longitudinal recess, the method comprising routing the at least one cable in the longitudinal recess. In one aspect of the invention, the frame comprises at least one horizontal member having a longitudinal recess and at least one vertical member having a longitudinal recess, and the method comprises routing the at least one cable through the longitudinal recess of the at least one horizontal member and through the longitudinal recess of the at least one vertical member. In another aspect of the invention, the frame further comprises at least one connecting element between the at least one horizontal member and the at least one vertical member, the at least one connecting element having a recess, and wherein the method comprises routing the at least one cable through the longitudinal recess of the at least one horizontal member, through the recess of the at least one connecting element, and through the longitudinal recess of the at least one vertical member. 
     Another aspect of the invention is a cabinet for mounting electronic equipment comprising a rectangular cylindrical frame having a top, bottom, and sides, the frame defining an internal cavity, and at least one power input unit for supplying power to at least some of the electronic equipment, wherein the at least one power input unit is mounted outside of the internal cavity. In one aspect of the invention, the at least one power input unit is mounted below the bottom of the frame. 
     Another aspect of the invention is a method of providing at least one power input unit to an electronic equipment cabinet, the cabinet comprising a support frame and the support frame defining an internal cavity of the electronic equipment cabinet, the method comprising: providing a power input unit; providing a power input unit interface for the electronic equipment cabinet positioned outside the internal cavity of the electronic equipment cabinet; and installing the power input unit in the power input unit interface. In one aspect of the invention, the electronic equipment cabinet further comprises at least one panel mounted to the frame, and wherein installing the power input unit comprises installing the power input unit without removing any panels from the electronic equipment cabinet. In another aspect of the invention, the support frame has a top and a bottom, wherein providing a power input unit interface comprises providing a power input unit interface below the bottom of the frame. 
     A further aspect of the invention is a trim piece mounting for an electronic equipment cabinet, the cabinet comprising a frame having at least one mounting surface, the trim piece mounting comprising: an elongated member having an inner surface and an outer surface; and means for attaching the elongated member to the mounting surface of the frame. In one aspect of the invention, the mounting surface of the frame comprises a perforated mounting surface and wherein the means of attaching the elongated member to the mounting surface comprises at least one projection located on the inner surface of the elongated member. In another aspect of the invention, the means for attaching the elongated member comprises at least one spacerthe at least one spacer comprising means for attaching the at least one spacer to the mounting surface of the frame and means for attaching the elongated member to the at least one spacer. In another aspect of the invention, the mounting surface on the frame comprises a plurality of threaded holes and the means for attaching the at least one spacer to the mounting surface comprises a threaded projection on the at least one spacer. 
     A still further aspect of the invention is a method of mounting a trim piece to an electronic equipment cabinet having a mounting surface, the method comprising: providing at least one spacer having a main body portion and a recess positioned in the main body portion; providing a trim piece having at least one extension engagable with the recess; mounting the at least one spacer to the mounting surface of the cabinet; and attaching the trim piece to the at least one spacer wherein the at least one extension engages the recess in the spacer. In one aspect of the invention, the mounting surface comprises a plurality of perforations, wherein mounting the at least one spacer to the mounting surface comprises engaging the at least one spacer with the plurality of perforations. In another aspect of the invention, the plurality of perforations comprises a plurality of threaded perforations and the at least one spacer comprises at least one threaded end, wherein mounting the at least one spacer to the mounting surface comprises threading the at least one threaded end of the spacer into the plurality of threaded perforations. 
     An even further aspect of the invention is a trim piece attachable to a mounting surface of an electronic equipment cabinet, the trim piece comprising: an elongated flexible member having an inner surface and an outer surface; and at least one extension on the inner surface for attaching the elongated flexible member to the mounting surface of the frame. In one aspect of the invention, the at least one extension comprises at least two elongated flexible extensions. In another aspect of the invention, the mounting surface comprises at least one spacer mounted to the mounting surface, and wherein the at least two elongated flexible extensions comprise at least two elongated flexible extensions having transverse projections, the transverse projections engagable with the at least one spacer. 
     The present invention addresses many of the limitations of the prior art including providing a secure support for the cabinet casters and seismic supports, providing recesses for the routing of electrical conduit, providing an easily accessible power input unit, and providing easily installable and removable trim pieces, that among, other things, provide a more pleasing appearance to the equipment cabinet. These and other embodiments and aspects of the present invention will become more apparent upon review of the attached drawings, description below, and attached claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, both as to organization and method of practice, together with further objects and advantages thereof, may best be understood by reference to the following detailed descriptions of the preferred embodiments and the accompanying drawings in which: 
     FIG. 1 is a front elevation view of an electronic equipment cabinet having one or more aspects of the present invention. 
     FIG. 2 is a perspective view of the structural frame and supports of the cabinet shown in FIG.  1 . 
     FIG. 3 is an exploded detailed view of one of the connections of the frame shown in FIG.  2 . 
     FIG. 4 is a detailed view of some of the structural members of the cabinet shown in FIG.  2 . 
     FIG. 5 is cross sectional view along the lines  5 — 5  shown in FIG.  4 . 
     FIG. 6 is a detailed view of the power input unit mounting for the cabinet shown in FIG.  1 . 
     FIG. 7 is perspective view of one power input unit that can be used for the present invention. 
     FIGS. 8A and 8B are perspective views of the mounting of trim pieces to an electronics cabinet according to another aspect of the present invention. 
     FIG. 9 is a cross-sectional view of the aspect of the invention shown in FIG. 8A as viewed along lines  9 — 9  in FIG.  8 A. 
     FIG. 9A is a detail view of the spacer shown in FIG. 9 according to one aspect of the invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 illustrates a typical elevation view of a rack or cabinet  10  having one or more aspects of the present invention. Cabinet  10  includes a rectangular cylindrical frame  12  which provides the structural support for the electronic components  13  (shown in phantom) mounted in cabinet  10 . Electronic components  13  may be computers, data storage devices, or communications devices, among others. Cabinet  10  also includes one or more panels  11 , typically sheet metal or plastic panels, that are typically mounted to the top, bottom, and sides of frame  12  to protect the equipment within and to provide an aesthetically pleasing appearance to cabinet  10 . Cabinet  10  of FIG. 1 also includes a set of casters  14 , for example, four casters, that are used to install and remove cabinet  10 . Though not clearly shown in FIG. 1, according to one aspect of the invention, casters  14  are not mounted to the sheet metal bottom (not shown) of cabinet  19  but casters  14  are rigidly mounted to the bottom support member of frame  12 . Also shown in FIG. 1 is a typical seismic support  16 . Seismic supports  16 , which are conventional floor mountings, restrain cabinet  10  from moving or being toppled during a seismic event, that is, an earthquake. Though only a single seismic support  16  as shown in FIG. 1 may be used, it is understood by those of skill in the art that two or more such supports  16  may be used when mounting electronic equipment cabinets such as cabinet  10 . As shown in FIG. 1, frame  12  of cabinet  10  may include a horizontal support ( 26  in FIG. 2) having a vertical projection  17  to which seismic support  16  can be mounted to frame  12 , for example, by means of mechanical fasteners  19 , for instance, threaded fasteners. Cabinet  10  may also include one or more leveling devices  15 , for example, adjustable leveling devices, for supporting cabinet  10  at a desired installed elevation and orientation. One or more leveling devices  15  may be threaded devices, or wedge-type devices, or ball-and-ramp type leveling devices. 
     According to one aspect of the present invention, cabinet  10  may be transported to its desired installation location by means of casters  14 . Then, when positioned as desired, leveling devices  15  may be adjusted to properly support cabinet  15  in its desired elevation, for example, relative to the flooring of the installation. This level adjustment may raise height of leveling devices  15  above the height of casters  14 , for example, wherein casters  14  are lifted off the floor of the installation. When located at its desired elevation, cabinet  10  may be secured to seismic mount  16 , for example, via mechanical fasteners, for instance, threaded fasteners. 
     According to one aspect of the invention, cabinet  10  also includes at least one power input device  18 , for example, a power distribution unit (PDU). Unlike conventional cabinets, power input unit  18  of cabinet  10  is mounted below and outside frame  12  of cabinet  10  so that the unit can be easily accessed. Unit  18  is inserted into a power input port  20  of cabinet  10 . As shown in FIG. 1, cabinet  10  includes at least two power input ports  20  for units  18 , and only one such power input unit  18  is installed. 
     FIG. 2 illustrates a perspective view of frame  12  of cabinet  10  shown in FIG. 1 with panels  11  removed. Frame  12  is typically comprised of extruded metal members, for example, extruded aluminum, formed into a cylindrical shape, for example, a rectangular cylindrical shape, though a circular cylindrical shape may also be used according to one aspect of the present invention. FIG. 2 also illustrates casters  14  and a seismic support  16  as shown in FIG.  1 . As shown in FIG. 2, frame  12  typically includes a plurality, typically four, vertical support members  22  and a plurality of horizontal support members  24 . According to another aspect of the present invention, FIG. 2 also illustrates a typical lower horizontal support  26  of frame  12 . Among other things, support  26  provides a surface for mounting cabinet  10 , for example, via casters  14  or seismic supports  16 . Support  26  provides a stiffer, more rigid mounting of cabinet  10  than conventional cabinets. Conventional cabinets are typical mounted to a less rigid bottom panel which can be prone to undesirable deflection, for example, under seismic loading. Again, though only one seismic support  16  is illustrated in FIG. 2, it is understood by those in the art that two or more seismic supports  16  may be used. 
     FIG. 3 illustrates an exploded detail view of one of the support member connections of frame  12  shown in FIG.  2 . Specifically, FIG. 3 illustrates the mechanical connection between two typically horizontal members  24 A and  24 B and typical vertical member  22  of frame  12 . Though these members may be fastened by any conventional means, for example, mechanical fasteners, in the embodiment shown in FIG. 3, the members are secured by means of connector  28 . Members  22 ,  24 A,  24 B, and connector  28  are typically made from extruded aluminum, though other materials may be used. Members  22 ,  24 A, and  24 B and connector  28  are typically secured to each other by welding, though mechanical fasteners or interference fits may be used. According to another aspect of the invention, at least one of members  22  and  24 A include a recess or cavity  30 ,  32 , respectively, in which electrical conduit may be inserted and routed as needed. Recesses  30 ,  32  are typically longitudinal recesses, that is, recesses that extend at least partially in the direction of elongation of members  22  and  24 A. As shown in FIG. 3, connector  28  may also include a corresponding recess  34  which communicates with recesses  30  and  32  such that conduit can be routed from recess  30  through recess  34  to recess  32 , or vice versa. As shown in FIG. 3, support members  22  and  24 A, and connector  28 , may include two recesses, or two or more recesses, for example, located on opposite sides of the members through which conduit may be routed. Thus, the support members  22  and  24 A, in addition to providing structural support for the electronic components in cabinet  10 , may also provide a pathway for routing conduit to and from the components  13  (see FIG. 1) mounted in cabinet  10 . FIG. 4 illustrates a detailed view of the of supports  22  and  24 A and connector  28  of FIG. 3 when assembled. The recesses  30 ,  32 , and  34  for electrical conduit that these elements provide when assembled are clearly illustrated in FIG.  4 . 
     FIG. 5 is an axial view down the axis of member  24 A as viewed along lines  5 — 5  in FIG.  4 . FIG. 5 also illustrates the connector  28  and a cover  36  that can be affixed over recess  32  in member  24 A. Cover  36  is typically a plastic cover having flexible extensions or tabs  38  that engage and are secured to the internal surface  40  of recess  30  in horizontal member  24 A, for example, via cooperating indentations or projections  41  (not shown) in surface  40 . For example, indentations or projections  41  may comprise notches or ribs, for instance, longitudinal notches or ribs,  41  as illustrated more clearly in FIG.  4 . 
     FIG. 6 is a detailed view of the power input units  18  mounted in the base of cabinet  10  of FIG. 1. A typical power input unit  18  that may be used for the present invention is shown in FIG.  7 . According to one aspect of the invention, power input unit  18  may be a power distribution unit, such as a PIM 24030 D power distribution unit (PDU) manufactured by Mack Molding of Arlington, Vt. though other types of units may be used. Power input unit  18  is installed in power input ports  20  mounted on mounting plate  43  in cabinet  10 . Power input ports  20  may be any typical electrical connection, but in the aspect of the invention shown in FIGS. 6 and 7, power input ports  20  are 6-pin male connectors. As shown in FIG. 7, power input unit  18  receives electrical power via an electrical cable  50  having a electrical connector  52 . Connector  52  can typically be plugged into a wall-mounted electrical outlet or other source of electrical power to supply power to cabinet  10  of FIG.  1 . 
     FIG. 6 illustrates the sheet metal bottom plate  42  which is mounted to the bottom of frame  12  (not shown in FIG.  6 ). According to the present invention, plate  42  includes at least one power input port  20  mounted on mounting plate  43 , though two such ports (one is hidden by units  18 ) are present in the aspect shown in FIG. 6, and at least one power input unit is installed into at least one port  20 . Note that since power input units  18  are readily removable, they can be installed at any time before, during or after installation. Furthermore, since units  18  are located outside frame  12  and external to, for example, plate  42 , units  18  are readily accessible for maintenance, service, or installation of electrical power. In addition, since unit  18  is located outside of frame  12  (see FIG.  1 ), unit  18  does not consume valuable space within the envelope of frame  12 . According to this invention, one or more units  18  may be installed after installation, that is, it is not necessary to install unit  18  during fabrication or during transport of cabinet  10 . 
     FIGS. 8A and 8B illustrate a further embodiment of the invention. FIGS. 8A and 8B are perspective views partially in cross-section similar to the perspective view shown in FIG.  3 . FIG. 8A illustrates the mechanical connection between two horizontal members  124 A and  124 B, similar to members  24 A and  24 B in FIG. 3, and typical vertical member  122 , similar to member  22  in FIG.  3 . Members  124 A,  124 B, and  122  comprise members of an equipment rack frame, such as frame  12  in FIG.  2 . As discussed earlier with respect to FIG. 3, members  124 A,  124 B, and  122  may be fastened by any conventional means, for example, mechanical fasteners. In the embodiment shown in FIG. 3, members  124 A,  124 B, and  122  are secured by means of connector  128 . Again, members  122 ,  124 A,  124 B, and connector  128  are typically made from extruded aluminum, though other materials may be used. Members  122 ,  124 A, and  124 B and connector  128  are typically secured to each other by welding, though mechanical fasteners or interference fits may be used. In one aspect of the invention, members  122 ,  124 A, and connector  128  include one or more recesses or cavities  130  (not shown),  132 , and  134 , respectively, in which electrical conduit may be inserted and routed as needed. 
     FIGS. 8A and 8B also illustrate recess cover pieces  136  and  137  which, according to one aspect of the invention, may be positioned over longitudinal recesses in support members  124 A and  122 , respectively. Cover pieces  136  and  137  may be similar to recess cover  36  shown in FIG.  5 . Similar to cover  36 , cover pieces  136  and  137  typically comprise a plastic cover having flexible tabs  138 , similar to tabs  38  of cover  36 , that engage and are secured to the internal surface recess  132  in horizontal member  124 A, and the recess (not shown) in vertical member  122 . Cover pieces  136  may have sides  136 A and  136 B which are essentially parallel to each other; however, in one aspect of the invention, sides  136 A and  136  may be non-parallel, for example, as shown in FIGS. 8A and 8B, side  136 A may have a curvilinear shape, for example, a parabolic shape. In one aspect of the invention, cover pieces  136  and  17  may include a power switch  139 , for example, for shutting off electrical power to one or more components in rack  10 . 
     According to the aspect of the invention shown in FIGS. 8A and 8B, vertical member  122  includes a trim piece  150  attached to vertical member  152 . As shown more clearly in FIG. 8B where trim piece  150  is shown detached from vertical member  122 , vertical member  122  (which may be similar to many vertical members in the art) typically includes a mounting strip  152  having mounting holes  154 , for example, threaded mounting holes. Mounting strip  152  may be integral with vertical member  122  or may be removably mounted to vertical member  122 , for example, by means of mechanical fasteners (not shown). Mounting strip  152  and mounting holes  154  are typically used in electronic cabinet design to mount electrical equipment in a cabinet, for example, by means of mechanical fasteners, for instance, mounting screws (not shown). According to one aspect of the present invention, trim piece  150  is mounted to mounting strip  152  to cover mounting strip  152  and conceal mounting holes  154  and any fasteners inserted into mounting holes  154 . Trim piece  150  is typically made from a plastic material, for example, a polyvinyl chloride (PVC)-type plastic, a polystyrene-type plastic, or their equivalents. In one aspect of the invention, trim piece  150  is attached to mounting holes  154  by means of a “snap on” fit, for example, by means of flexible projections (not shown) which project into and engage one or more mounting holes  154  to retain trim piece  150  on mounting strip  152 . In one aspect of the invention, trim piece  152  comprises one or more, trim pieces  152 , which may extend partially or completely along the length of vertical member  122 , for example, extend over essentially the entire height of cabinet  10 . 
     A detail of one aspect of the invention shown in FIGS. 8A and 8B is shown in FIG.  9 . FIG. 9 illustrates a cross-sectional view of trim piece  150  and mounting strip  152  as viewed along lines  9 — 9  shown in FIG.  8 A. As shown in FIG. 9, mounting strip  152  may be L-shaped having one leg  152 A mounted to vertical member  122  (not shown in FIG. 9) and one leg  152 B having mounting holes  154 . As shown in FIG. 9, according to one aspect of the invention, trim strip  150  is mounted to mounting strip  152  by means of at least one stand-off spacer  156 , typically, a plurality of spacers  156 . Spacers  156  are mounted to mounting strip  152 , for example, via mounting holes  154 , and one or more trim pieces  150  are mounted to spacers  156 . In one aspect of the invention, spacers  156  are metallic, for example, steel, stainless steel, or aluminum, but in another aspect of the invention spaces  156  may be non-metallic, for example, a plastic. Spacers  156  may be mounted to mounting strip  152  by any conventional means, for example, snap-fit, by adhesives, or even by welding or brazing, but in one aspect of the invention, spacers  156  are threaded, for example, threaded on one end  158 , and spacers  156  are mounted to mounting strip  152  by screwing end  158  into complementary threaded holes  154  in mounting strip  152 . 
     FIG. 9A illustrates a detailed view of spacer  156 . In one aspect of the invention, spacer  156  comprises a cylindrical main section  160 , for example, circular cylindrical or rectangular cylindrical, having a recess, slot, or gap  162 . When main section  160  is circular cylindrical, recess  162  may be an annular slot at least partially encircling body section  160 . When main section  160  is rectangular cylindrical, recess  162  may be a longitudinal or lateral recess or slot on the side of body section  160 . According to one aspect of the invention, spacer  156  has a height H of between about 0.30 inches and about 0.80 inches; a width or diameter W of between about 0.30 inches and about 0.60 inches; and an inner width or diameter w of between about 0.15 inches and about 0.25 inches. In one aspect of the invention, when the main section  160  is rectangular cylindrical in shape, the length of main section  160  may be about equal to the width W of main section  160 , however, the length of main section  160  may be longer than width W, for example, twice or three times or more as long as width W. 
     According to the aspect of the invention shown in FIG. 9, trim piece  150  includes extensions  164  having projections  166 , for example, transverse projections  166 , which engage slots  162  in spacer  156 . In one aspect of the invention, extensions  164  are elongated extensions which extend at least partially along the length of trim piece  150 . In one aspect of the invention, extensions  164  extend along the entire length of trim pieces  150 . In another aspect of the invention, extensions  164  are annular extensions and at least partially encircle, or completely encircle, circular cylindrical main section  160  of spacer  156 . In one aspect of the invention, extensions  164  define a cavity in trim piece  150  having a bottom  168  which contacts spacer  156 . Extensions  164  are preferably flexible and radially or laterally deflect outward when trim piece  150  is compressed against one or more spacers  156  and then radially or laterally deflect inward wherein projections  166  engage recesses  162  to retain trim piece  150 . 
     The outer surface  170  of trim piece  150 , which may be exposed to view, may be colored, decorated, or contoured to provide a pleasing appearance to trim piece  150 . Trim piece  150  may also include a side extension  172  to further conceal mounting strip  152  and also conceal spacers  156  and extensions  164  from view. 
     According to one aspect of the present invention, first, one or more, typically a plurality, of spacers  156  are threaded into threaded holes  154  in mounting strip  152 . Then, one or more trim pieces  150  are positioned above spacers  156  and compressed against spacers  156  wherein extensions  164  and projections  166  first deflect and then engage recesses  162  in spacers  156 . Trim piece  150  can simply be removed by pulling on trim piece  150  wherein extensions  164  again deflect and projections  166  disengage recesses  162 . According to one aspect of the invention, trim pieces  150  may be repeatedly attached and removed as needed. 
     According to another aspect of the invention, trim pieces  150  can be engaged to spacers  156  with little or no deflection of extensions  164 . In this embodiment of the invention, one or more trim pieces  150  are engaged to spacers  156  by positioning an end of one trim piece  150  so that projections  166  engage recesses  162  and then slidably engaging projections  166  into recesses  162  in one or more spacers  156 . In this aspect of the invention, trim pieces  150  are preferably made from a flexible material, for example, sheet metal or plastic, to facilitate engaging projections  166  in slots  164  and sliding one or more trim pieces  150  to engage further spacers  156  to attach one or more trim pieces  150  to mounting strip  152 . 
     The aspects of the present invention provide numerous advantages over prior art electronic equipment racks. In one aspect of the invention, an equipment rack is provided that provides a more rigid support for mounting hardware, such as casters and seismic supports, than is provided by prior art racks by mounting this hardware directly to the cabinet frame. Another aspect of the invention, facilitates the routing of wires and cables by providing cable routing paths in the horizontal and vertical members of the frame of the rack. Another aspect of the invention, improves the accessibility of power input modules while reducing the impact of the modules on the space within the rack. Still another aspect of the present invention provides easily attachable trim pieces which conceal unsightly mounting holes in the rack. 
     While the invention has been particularly shown and described with reference to preferred embodiment, it will be understood by those skilled in the art that various changes in form and details may be made to the invention without departing from the spirit and scope of the invention described in the following claims.