Abstract:
The portable workstation includes a frame having an adjustable mounting mechanism, which permits the case to be mounted on a variety of telecommunication equipment racks and other field structures. When mounted on the rack, the workstation provides a horizontal surface for working on fiber optic cables or other telecommunication equipment. A smooth, clean surface for working on fiber optic cables is an essential requirement for users of the workstation. The workstation includes a drawer for storing tools, instruments, and supplies required for working on fiber optic cables or copper wire. The drawer slides in and out of the frame when the workstation is mounted on the rack to provide convenient access to the contents. The frame of the workstation is formed from extruded metal and includes an internal channel for the drawer and an external channel for securing the adjustable mounting bars. The bars are adjustable to accommodate the various rack or other mounting configurations used in the telecommunication and other industries.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a portable workstation for rack mounting, and more particularly, to a workstation for field use when servicing fiber optic telecommunications equipment. The workstation includes a special mounting fixture which provides a means for mounting the workstation on a fiber optic telecommunications rack, ladder, pedestal, or other stationary field stand. The workstation includes a storage area for tools and supplies, and a clean work surface for working on the fiber optic and related communications equipment. 
     SUMMARY OF RELATED ART 
     Fiber optic technology is the transmission of energy by light through glass fibers, and is used to transmit and receive analog and digital signals. Fiber optic cable is the premier medium to meet the demand for higher speeds and greater information carrying capacity. Telephone, cable television, communication companies, and other businesses around the world are investing billions of dollars in fiber optic lines which have an enormous capacity for carrying data. Because of the advantages of fiber optic systems over conventional electrical and electronic components and systems, significant growth and expansion is anticipated in the use of fiber optic systems. 
     One of the main advantages of the fiber optic system is the ultra clear and clean signals in such system. Fiber optic systems are non-conductive, and are not effected by interference from radio frequency or electromagnetic fields. The losses associated with the transmission of fiber optic signals are significantly less than the losses in an electrical system. Another major benefit of a fiber optic system is the greater information carrying capacity. The fiber optic cable is significantly smaller and lighter in weight than the comparable copper conductors required for equivalent transmission capabilities. Optical data is transmitted through fiber optic cable at speeds up to 100 times faster than data transmitted using copper wire. 
     A typical fiber optic system consists of a transmitter, a transmission medium, and a receiver. The transmission medium is a fiber optic cable which includes a core made from extremely pure glass drawn out into a fine strand that is strong and flexible. The fiber optic cable also requires an outer sheath or cladding formed around the highly transparent core of glass that carries the light. The cladding reflects light back into the core such that the light is propagated by internal refraction. Fiber optic cable is classified by transmission type (single mode, graded index multimode, etc.) and by core/cladding diameter (i.e. 62.5/125 microns). 
     The single mode fiber only propagates one mode of light which makes it highly efficient. This type of cable is used with laser sources and requires an exact coupling alignment to a well-defined beam of light. The graded index multimode fiber exhibits a variable core density cross-section, which reduces intermodal dispersion and acts to focus broader bandwidths of reflected light into the fiber&#39;s core. Precision alignment of splices and connections are also essential in the graded index multimode fiber. 
     The single mode and/or multiple mode fibers can be assembled into multi-fiber bundles with a single outer cover. The bundles may include a central strength member for additional strength during installation. The bundle is designed to facilitate the splitting out of individual fibers for connection purposes. 
     The core size may be as small as 10 microns in diameter for a single mode fiber and as large as 85 microns for a multiple mode fiber. When the cladding is included, the total diameter for a single mode fiber can range up to 125 microns. The single mode fiber is very efficient at transmitting light, but such fiber has a small numerical aperture and is not effective in gathering light. Consequently, the single mode fiber is generally used for long distance applications with laser light transmitters, which can provide a concentrated beam of light. The multiple mode fiber has a much larger numerical aperture, but is less efficient at transmitting the light. The multiple mode fibers are used with light emitting diodes with a broader light wave for more local applications (50 miles or less). The diameter for multi mode fibers ranges from 125 microns to 400 microns. 
     In fiber optic systems, engineers and technicians perform power budget calculations to determine original and periodic operational system integrity in regard to attenuation. The transmitter spectral output power and receiver maximum sensing range are compared to the system losses in the fiber, connectors, splices, and couplers. The transmitter and receiver must be sized to ensure power to propagate the signal from the source to the receiver. 
     The total attenuation is significantly affected by the quality of the connections and/or splices in the fiber optic system. The losses at a dirty or poor quality connection can easily increase losses in the fiber optic system by as much as ten times the projected amount for a high quality connection. Poor quality connections are the most frequent cause of power loss, which results in operating defects and breakdowns in the fiber optic system. 
     Each fiber optic system will have optical connections at each junction between a fiber optic cable and a light source or detector. Connections are also needed to join or splice together the ends of two cables. Since each fiber optic system will include a number of junctions of fiber optic cable, it is essential that the technicians working on fiber optic cables in the field have a clean and convenient surface for properly connecting the fiber optic cables. 
     In the installation of a fiber optic system, transmitters and receivers may be positioned throughout the system at the desired locations for transmitting and receiving signals. The transmitters and receivers are mounted in a light interface unit which includes both electrical receptacles for input/output of electrical signals and lighting receptacles for the input/output of light signals. After the light interface units with transmitters and receivers have been installed and the cable between the light interface units pulled, one of the final field steps to complete the installation is connectorization, which is the connection of fiber optic connectors to the ends of the fiber optic cables to facilitate the proper alignment of the core of the fiber optic cable at the fiber optic connections. 
     The fiber optic cables used in a system will have a connector secured to each end of the fiber optic cable, the connector being designed for insertion and locking in the receptacle. The cable is stored on spools and is pulled from the spools in the field during installation. Several different types of receptacles and connectors are available for use in fiber optic systems. 
     The connectorization will typically occur at a telecommunications rack. The racks come in various sizes, but the two standard widths for such racks are 19 inches and 23 inches. The light interface units and the other components in the system are mounted on the rack. The racks are frequently mounted in a storage area or other enclosed facility where space is at a premium. 
     The connectors are usually installed on the fiber optic cable in the field at the time of installation. The fiber optic cable is stripped of its protective covering and the glass core and cladding are inserted into the connector such that the glass core extends from the ferrule at the end of the connector. The cable is epoxied into the connector and the glass core at the end of the ferrule is cleaved and polished using a lapping process. 
     The polished end of the core of the cable must be inspected to ensure that the end surface is clean and scratch free. Any scratches or cracks in the end of the glass fiber will adversely effect the integrity of the connection. Even body oils, lint or dust can cause unacceptable losses at the connection. 
     Because a good connection is essential to the overall efficiency of the system, a technician working on fiber optic connections requires a clean and convenient workstation for use in the field. The technician in the field must be able to inspect the end of the core of the fiber optic cable to ensure a smooth and clean surface for transmission of the light. The technician must have a place to rest his tools and materials when attaching the connectors to the fiber optic cable, which typically requires a clean, flat surface to work upon. A clean and convenient place to store tools and work materials is also desired by the technician. 
     As the application of fiber optic systems for business and personal use has increased, the demand for technicians to install and service the systems has not kept pace. In addition, there is a critical need for tools and supplies which are suited for use by technicians in the installation and servicing of the fiber optic systems. 
     One of the problems in field work is obtaining a clean, flat work surface to work on the fiber optic cable. The areas where telecommunication racks are located do not usually have a work surface available for the technician. Because a clean work area is important to achieving a proper fiber optic connection, technicians prefer using their own workstation. But positioning a workstation at a convenient height for performing service work is typically a problem. Technicians cannot carry a full size station and in most field locations, there are no tables or flat surfaces available for positioning a portable workstation at the desired height. 
     Another important consideration for technicians in the field is the convenience in transporting the workstation. Technicians need a workstation which includes the capability of carrying their tools, work supplies, and a work surface all at one time to minimize the need to make additional trips to carry such items to the site where the work is performed. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, there is provided a portable workstation that can be mounted on a telecommunications rack, ladder, pedestal, or other stationary field stand to provide a sturdy, horizontal work surface and tool storage area. The workstation is ideally suited for use in field inspection and work on fiber optic components, copper wire, and other electronic components. 
     A technician working on copper wired systems primary need is for a tool box with supplies and tools to perform necessary services in the field. In addition, a technician working on fiber optic systems needs not only supplies and tools, but also a clean working surface to clean and polish the fiber optic cables and to perform the connections required in a fiber optic system. The portable workstation of the present invention provides a technician with an easy to carry combination unit that provides both a tool box for tools and supplies, and a work surface for performing the services in the field. By adjusting the mounting mechanism, the workstation is mounted on the fiber optic rack such that the work surface is horizontal for convenient use. A clamp-like bracket may also be provided which enables a technician to clamp the workstation onto ladders, pedestals, and any other stationary field stand. 
     The workstation is formed from a U-shaped, extruded frame. The frame may be made by forming a single length of extruded metal or by welding individual frame members together. The frame includes an internal channel which forms a mounting track for a drawer. The drawer is inserted into the channel at the open side of the U-shaped frame. The drawer slidingly engages the channel such that the drawer is moveable between a closed position inside the frame and an open position extending from the frame. In order to carry the portable workstation, the drawer can be secured in the closed position to permit transport of the workstation. 
     Tools, supplies, instruments, and other items are stored in the drawer. The standard size drawer fits totally within the frame of the workstation. Larger size drawers may also be used in which the drawers are deeper and extend from the frame opposite the cover. A layer of foam with cutouts may be positioned inside the drawer to store and protect the tools and instruments. Mutiple layers of foam inserts may be used to provide additional storage area. 
     The workstation also includes an adjustable mounting mechanism to secure the workstation to the telecommunication racks. The mounting mechanism is adjustable so that the workstation can be used on mounting racks, ladders, pedestals, and other stationary field devices of varying widths. The U-shaped frame includes an external channel, and mounting bars may be inserted in the channel of the frame. The position of the bars can be adjusted within the channel so that the mounting mechanism is aligned for mounting on the rack. The bars are typically inserted at opposite ends of the external channel of the cross member of the frame, which extends between the two side members of the frame. The mounting bars have a mounting hole situated in a biased forty-five degree angle from a vertical position. The mounting holes are used to mount the workstation on mounting bolts extending from the rack. 
     The bars may also be configured for securing the workstation to field devices, such as ladders, pedestals, and other stationary field stands. A set of vice-type threaded cinching knobs and mounting bars are used for such mounting configuration. Different positioning and configurations of the end members can be used to mount the workstation on a majority of rack and other structures used in the communications industry and other similar applications. 
     A cover is mounted on the frame adjacent the open side of the drawer. The cover is secured to the frame and is positioned over the contents of the drawer when the drawer is in the closed position. The cover has a flat, hard outer surface which serves as a work area when the workstation is mounted on the rack. The cover is designed to be scratch resistant and easy to clean. The smooth outer surface does not retain oil or dust or other contaminants which my come in contact with the surface during use or when in transport or storage. 
     All of the mounting configurations are arranged such that the outer surface of the cover provides a horizontal work surface for a technician to work on fiber optic and other communication systems deployed on the rack. The workstation can be mounted on the rack at the height most suitable for performing the service work. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which: 
     FIG. 1 is front elevational view of a portable workstation mounted on a telecommunications rack, including adjustable mounting bars for securing the workstation to the rack; 
     FIG. 2 is a perspective view of an adjustable mounting bar extending from the workstation and mounted on a bolt in the rack; 
     FIG.  3 . is a side elevational view of the workstation mounted on a telecommunications rack; 
     FIG. 4 is a perspective view of the frame of the workstation; 
     FIG. 5 is a perspective view of the drawer which is positioned in the frame of the workstation, and FIG. 5A is front elevational view of an alternative drawer configuration with an extended storage area; 
     FIG. 6 is a partial cross-sectional view of the drawer with a foam insert in the drawer; 
     FIG. 7 is a partial cross-sectional view of the drawer with two foam inserts to provide an additional storage area; 
     FIG. 8 is a back view of the workstation showing the mounting bars in the channel of the frame; 
     FIG.  9  and FIG. 9A are side views of alternative workstation configurations; 
     FIG. 10 is an end view of an alternative extrusion used to form the frame, such configuration having an additional channel for securing the cover which forms the work surface; 
     FIG. 11 is a front end view of side member of a frame with the alternative extrusion, with the partial cover, drawer, and mounting bar also shown; 
     FIG. 12 is a side view of an adapter mounted on the workstation for securing the workstation on a ladder, with the mounting bars and frame shown in cut away view; and 
     FIG. 13 is a top plan view of the extended extrusion before cutting and welding to form the frame of the workstation. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIGS. 1-3, a portable workstation  10  of the present invention is mounted on a fiber optic rack  12 . The rack  12  also includes a fiber optic patch or connection panel  14  having fiber optic cables  16  which require cleaning and connection to the terminals of the fiber optic patch panel  14 . 
     The workstation  10  includes a U-shaped frame  18  having a drawer  20  positioned within the frame  18 . The drawer  20  may be slid out of and then back into the frame  18  to provide access to the contents of the drawer  20 . A hole  22  may be drilled in the side of the drawer  20  to provide a means for opening and closing the drawer. Other handle mechanisms are also acceptable for opening and closing the drawer  20 . 
     A cover  24  is secured to the edge of the frame  18  and provides a horizontal work surface for working on the fiber optic cables. The type of work performed on the fiber optic cables  16  is described in my pending application Ser. No. 09/361,703 and my U.S. Pat. Nos. 5,982,533 and 5,731,893, which material is incorporated herein by reference. 
     The cover  24  may be secured to the frame  18  in a number of different ways. The cover  24  may be glued or epoxied to the frame  18 . Clips or other fasteners may be used to secure the cover  24  to the frame  18 . The U-shaped frame  18  may be provided with a separate groove or channel extending around the upper edge of the frame  18 , such channel facilitating the insertion and retention of the cover  18  in the channel (FIG.  11 ). The cover  24  is preferably made from PVC or other similar material. The PVC cover  24  is easy to keep clean and is very durable in field environments. A smooth, clean working surface is very important when working with fiber optic cables  16 . The PVC cover does not absorb oils or other contaminants which may come in contact with the cover  24 . 
     Mounting bars  26  are adjustably secured to the frame  18 . The frame  18  includes an external channel  28  to retain the bars  26  and the bars can be slid along the channel to accommodate various widths of the rack  12 . The standard fiber optic telecommunication racks are typically 19 inches or 24 inches in width. By sliding the bars  26  in the channel  28 , the bars  26  can be positioned for mounting on racks of varying width. The external channel  28  is typically required only on the back surface of the frame  18  along the cross member  30 . However, to simplify the manufacturing process, the same frame member configuration is used for both the cross member  30  along the bottom of the U-shaped frame  18  and the two side members  32  of the frame  18 . The external channel  28  is the same for both the cross member  30  and the side members  32 . 
     The rack  12  includes a column of pre-drilled and tapped holes  34 . All racks in the telecommunications industry have the same hole size and pattern. To secure the workstation  10  to the rack  12 , a screw  36  is secured on each side of the rack  12  in holes  34  at the same height. The mounting bars  26  include a forty-five degree angle biased key hole  38 . Instead of having the key hole with the narrow portion aligned vertically above the wider opening, the keyhole is formed at a forty-five degree offset from the typical vertical configuration. The purpose of the forty-five degree angle biased key hole  38  is to cause the bars  26  to slide inward when the workstation  10  is mounted on screws  36  of the rack  12 , which promotes a more secure locked-in position for the bars  26  in the external channels  28 . The mounting bars  26  are adjusted in the external channels  28  until the key holes  38  are aligned with and then positioned on the screws  36  in the rack  12 . 
     In FIG.  3  and FIG. 9, an optional support line  40   a ,  40   b  is shown which may be used to steady the workstation  10  when mounted on the rack  12 , and may also be used to retain the bars  26  in the external channels  28  when the workstation is not mounted on the rack  12 . The support line may be made of elastic material  40   a  (FIG.  3 ), may be a spring loaded wire  40   b  (FIG.  9 ), or other similar line which has some elasticity. The support line  40   a  has one end secured to a side member  32  of the frame  18 . The other end of the support line has a hook  42 . The support line  40   a  can be secured in hole  34  of the rack to provide additional stability to the workstation  10  (FIG.  3 ). The mounting bars  26  by themselves are sufficient to secure the workstation  10 , and such a mounting configuration can support up to one hundred pounds. The support line  40   b  is also used as a means for securing the mounting bars  26  in the external channel  28  when not mounted on the rack  12  (FIG.  9 ). The hook  42  is hooked in the key whole  38  to prevent the bars  26  from sliding out of the channel. 
     Other support mechanisms could be used to support the workstation  10  when mounted, and other fasteners or locking mechanisms could be used to secure the bars  26  in the external channels  28  when being transported. For example, telescoping legs could be pivotably mounted on the side members  32  and secured along the side members  32  when not in use. When required, the telescoping legs could be pivoted and extended to support the workstation  10  engaging the rack  12  or the ground. 
     One embodiment of the frame  18  is shown in FIG.  4 . The U-shaped frame as two side members  32  and a cross member  30 . The corners  44  are welded along the edges of the miter joint formed by at the junction of the cross member  30  and the side members  32 . In addition to the external channel  28 , the frame  18  includes an internal channel  46  to receive and support the drawer  20 . The drawer  20  slides in the internal channel  46  between a closed position when fully inserted in the channel  46  and an open position when the drawer  20  is extended from the frame  18 . 
     The rectangular drawer  20  shown in FIG. 5 is a basic drawer made from composite material, wood, or other suitable material. Using a hole  22  to open and close the drawer  20  keeps a flat surface along the outer edge of the drawer  20 . Other mechanism would also be suitable for opening devices. The drawer  20  and frame  18  are typically 14-16 inches wide, 12-15 inches deep, and 2.5-3.5 inches in height. The frame  18  is typically made from an extrudable metal, such as aluminum. The frame  18  is preferably extruded to facilitate the forming of the external channel  28  and the internal channel  46 . 
     FIG. 5A shows an alternative configuration for the drawer in which a bottom segment  84  of the alternative drawer  82  is extended to provided additional height to the drawer for added storage capacity. The sides  86  of the alternative drawer  82  are maintained in the same configuration to ensure proper mounting of the alternative drawer  82  in the frame  18 . The height of the alternative drawer  82  is typically 3-4 inches. 
     FIGS. 6-7 show how foam inserts can be used inside the drawer  20  to secure and protect tools, instruments, and supplies. In FIG. 6, a single foam layer insert  48  is secured on a shelf board  49  and positioned within the drawer  20 . The foam layer insert  48  includes cutouts  50  to form storage areas for tools and instruments. The foam insert  48  is supported on spacers  52 , which supports the insert  48  above the base of the drawer  20  to form an additional storage area  54  for documents, supplies, and other items carried in the workstation  10 . The shelf board  49  with foam insert  48  rests on the spacers  52  and can be easily lifted to gain access to the additional storage area  54 . FIG. 7 shows a drawer  20  having a second foam layer insert  56  positioned beneath the shelf board  49  of the first foam insert  48 . Storage areas  58  may also be formed in the second foam insert  56 . 
     The positioning of the mounting bars  26  in the external channel  38  of the cross member  30  is shown in FIG.  8 . The bars  26  can be positioned in the channel  28  until the keyhole  38  is aligned with the screws  36  on the rack  12 . The retention means, such as the support line  40   b  (FIG.  9 ), can be used to retain the bars  26  in the channel  28 . The bars  26  are made from aluminum or other suitable metal. The height of the bars  26  is approximately 2 inches and the bars can have a length of 6-8 inches. 
     FIG. 9 shows the support line  40   b  with a spring  60  and a wire extension  62 . The support line  40   b  can be mounted in several different locations along the side member  32 . The support line could be mounted in the channel  28  and extend through a hole in the top of the channel  28 . The support line  40   b  could also be mounted on the outer surface of the side member  32  adjacent the cover  24 . 
     FIG. 9 also shows a handle mechanism formed by an elastic, nylon, or canvas strap  64  secured to the frame by clip  66 . When the workstation is not mounted on the rack  12 , the strap  64  is positioned around the end of the side member  32  and engages the side of the drawer  20  to retain the drawer in a closed position (FIG.  9 ). When the workstation  10  is mounted on the rack  12 , the strap  64  can be positioned about the bottom edge of the side members  32  of the frame  18  opposite the cover  24  so that the drawer  20  can be moved to the open position. 
     An alternative mounting strap configuration and locking mechanism is shown in FIG.  9 A. The carrying strap  88  is looped around an aluminum bar  90  secured in the external channel  28  of the side member  32 . A binding post  92  is secured in the external channel  28 . The end of the strap  88  is selectively secured to the binding post  92  by a D-ring  94  and an elastic band  96  made from rubber or other similar material. When the elastic band  96  is secured to the binding post  92 , the carrying strap  88  remains adjacent the drawer  20  in a brief case-type carrying configuration. When the elastic band  96  is detached from the binding post  92 , the looped carrying strap  88  may be pulled through the external channel  28  until the D-ring engages the bar  90 . In the detached position, the carrying strap  88  may be extended away from the workstation and be used as a shoulder harness to carry the workstation. A latch  98  may be used in connection with the carrying strap  88  so that the strap  88  can be unlatch to facilitate the movement of the drawer  20  to an open position. 
     The alternative configuration shown in FIG. 9A also includes an aluminum travel clip  100  pivotably mounted to the binding post  92 . The clip  100  can be rotated to extend across the external channel  28  of the cross member  30  to retain the mounting bars  26  in the external channel  28  during travel of the workstation. The clip  100  can be pivoted away from the mounting bars  26  when the bars  26  are extended for mounting on the rack  12 . 
     FIGS. 10-11 show an alternative frame configuration  18   a  with an additional internal channel  68  formed to retain the cover  24 . The configuration of the external channel  28  and the internal channel  46  in alternative frame  18   a  are similar to the configuration used in frame  18 . The cover  24  is slid into the channel  68  and is secured in place in the frame  18   a . The channel  68  can provide a smoother outer edge compared to an outer edge of the cover  24 , so there is less likelihood of damaging a fiber optic cable  16 . There is no change in the functioning of the bars  26  in the external channel  28  of the cross member  30 . 
     As shown in FIGS. 10-11, the frame  18   a  may also include a small retention flange  25  formed in cover channel  68  for insertion into the corresponding cover groove  25   a  formed along the outer edges in the top surface of the cover  24 . This flange and groove configuration provides a very secure mounting of the cover  24  on the frame  18 . 
     When mounting the workstation  10  on telecommunication racks  12 , the preferred positioning of the mounting bars  26  is to insert both bars  26  in the external channel  28  of the cross member  30 . However, use of the workstation for other applications, such as ladders, pedestals, or other stationary field stands, may require alternative mounting configurations. For ladders and other field stations which have cross members, an adapter kit may be provided for each of the mounting bars  26 . 
     As shown in FIG. 12, the mounting bar  26  includes a counter sink hole  102  drilled through the bar  26 . The adapter kit consists of an elongated screw  104 , a mounting bracket  196  and a screw-on handle  108 . The elongated screw  104  is positioned in the counter sink hole  102  such that the head of the screw  104  is recessed within the bar  26 . The mounting bracket  106  may then be slid onto the elongated screw  104 . A screw-on handle  108  is then screwed on until the mounting bracket  106  is tightly engaging the object on which the frame  18  is mounted, such as the ladder cross member  110  shown in FIG.  12 . The cross member is secured between the mounting bars  26  and external channel  28  on one side and the mounting brackets  26  on the other side. 
     At least two adapter kits are required for mounting the workstation to a ladder or other similar field stand. Other configurations of the mounting bracket  106  may be used. A flange or other hooking-type configuration may be used to mounting bracket  106  to ensure that the workstation is firmly secured. The mounting bracket  106  may be coated with a rubber coating or other non-slip coating to further improve the mounting. 
     When constructing the workstation  10 , using the same channel configuration for both the cross member  30  and the side members  32  provides certain efficiencies in manufacturing the frame  18 . The extruding of the frame material and the formation of the frame  18  are the most important steps in the manufacturing process. After the frame is formed, the cover  24  is secured to the frame  18 . The insertion of the drawer  20  and the mounting bars  26  in the frame  18  complete the formation of the basic workstation  10 . 
     Aluminum can be extruded in long pieces with the appropriate channels for the frame  18  or frame  18   a . The extruded aluminum is then cut into appropriate length pieces  72  as shown in FIG. 13 to accommodate various size workstations. The preferred length of the extruded aluminum pieces  72  is 42-48 inches. The piece  72  of aluminum is then cut as shown in the top plan view of FIG.  13 . The external channel is saw cut along line  74  to the vertical wall  75 . The cut  74  occurs in two places at equal distance from the ends  76 . Then four bevel cuts, to the vertical wall  75 , are performed along lines  78  and the miters  80  are removed. After the six cuts are completed, the piece  72  is bent in two places and welded to form miter joints at the corners  44 . The vertical wall  75  has not been cut and remains intact to provide a strong corner. The edges of the miter joint in corner  44  are welded along the lines shown in FIG.  4 . Such frame construction with strong corners provides a sturdy workstation  10 , and the frame is capable of supporting the weight in the drawer  20  and cover  24  as well as live loads up to 100 pounds, even when the frame  18  is mounted on the rack  12 . Such frame construction method is much stronger than cutting three separate pieces of metal to form the cross member and the two side members and then welding the three pieces together. 
     After the frame  18  is formed, the cover  24  is attached to the frame  18 . As noted above, the frame can be epoxied to the upper surface of the frame  18 . If the frame  18   a  is used with the second internal channel  68 , the cover  24  is inserted into the channel  68  to secure the cover  24 . The mounting bars are then inserted into the external channel  28  and the drawer  20  is inserted into the internal channel  46 , which completes the main steps of the formation process. Additional accessories, such as support lines, retention clips, foam inserts, and a handle strap may be added to the workstation as discussed above. 
     In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.