Abstract:
A pivotable work table for use with an electrical junction box is disclosed. The work table has a table member which is pivotally movable between a retracted position within the junction box and an extended position in which the table is oriented perpendicular to the box. The table member is hingedly connected to one or more retention pins which extend from the table member and slidably engage one or more respective bosses attached to the junction box. Coil springs coaxially disposed around the retention pins provide biasing forces which draw the table member toward the bosses and maintain the table member in either the retracted or extended positions.

Description:
FIELD OF THE INVENTION 
     This invention relates to work tables which are movably attached to a device or structure to provide a work surface which can be stowed away when not in use. 
     BACKGROUND AND OBJECTS OF THE INVENTION 
     Junction boxes and other devices used for telecommunications, cable television, power distribution, control systems and the like often require servicing by technicians to, for example, add new telephone or cable service lines, replace malfunctioning components, polish and splice optical fibers, or replace circuit breakers or spent fuses. The technician must often use a number of tools or handle numerous small parts when servicing a box, and many technicians find it convenient to bring a portable work table which they set up near the box to provide a ready surface upon which to place their tools and components while they work. 
     While the use of a work table may be convenient, carrying the table from one site to another, setting it up and breaking it down is not. Additionally, the junction box or other device to be serviced may be mounted high above the ground on a structure such as the side of a building, a utility pole, or a microwave or a radio transmission tower, where there is no convenient place to set up an extra table for use by the technician. 
     Clearly there is a need to provide a convenient work table for use by technicians servicing equipment which would be useable under all conditions no matter where the device to be serviced was located. Ideally the work table should require only a minimum of time and effort to set up and break down, and it furthermore should not comprise an extra piece of equipment which a technician must transport to and from a work site. 
     It is an object of the invention to provide a convenient work surface for use by a technician when servicing a device. 
     It is an object of the invention to provide a work table which pivots between a retracted position where the table is out of the way, and an extended position in which the table provides a work surface to hold small tools and components. 
     It is yet another object of the invention to provide a work table which is positioned to catch small parts or tools if they are dropped by the technician. 
     SUMMARY OF THE INVENTION 
     The pivotable work table according to the invention provides a solution to the above identified problems. The work table is designed to be permanently mounted on the housing of a junction box or other device, either as a retrofit to the box or as original equipment. The table pivots between a retracted position, in which the table is fully enclosed within the housing of the box and out of the way, and an extended position in which the table presents a work surface which extends substantially at a right angle to the housing convenient for the placement of tools, components and the like. The table thus positioned is idealy suited to catch small parts which fall from the device or are dropped by the technician. Fewer parts will be lost or damaged if the pivotable work table according to the invention is used. 
     The pivotable work table has a table member comprising a substantially flat plate providing the work surface. A surface portion is disposed along one edge of the table member and oriented perpendicular to the plate. A hinge member is mounted on the plate adjacent to the surface portion. 
     A mounting assembly preferably comprising a boss is attached to the housing on which the work table is to be mounted and the surface portion of the table member is arranged adjacent to the boss with the hinge member opposite the boss. The boss has a surface facing the hinge member. 
     The mounting assembly further preferably comprises an interconnecting member hingedly attached to the hinge member and movably engaging the boss, thus providing a connection between the boss and the table member. A biasing member is disposed between the interconnecting member and the boss for biasing the table member toward the boss. The table member is pivotable via the hinge member between a retracted position in which the plate is oriented substantially parallel to the surface of the boss, and an extended position in which the plate is oriented substantially perpendicular to the surface of the boss. When the table member is in the retracted position the biasing member serves to urge an edge of the surface portion into contact with the surface of the boss and keep the table member in the retracted position. When the table member is in the extended position the biasing member serves to urge a region of the surface portion into contact with the surface of the boss and keep the table member in the extended position. 
     These and other objects of the invention will become apparent upon consideration of the drawings and detailed description of the preferred embodiment. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross sectional view from above showing a pivotable table in its extended position mounted within a building entry protection unit (BEP); 
     FIG. 2 is a cross sectional view taken along line 2--2 of FIG. 1 showing a pivotable table in its extended position mounted within a BEP, the BEP being only partially illustrated; 
     FIG. 3 shows the pivotable table of FIG. 2 in its retracted position; 
     FIG. 4 is a detailed cross sectional view of a portion of FIG. 2 on an enlarged scale; 
     FIG. 5 is a detailed cross sectional view of a portion of the pivotable table mounted within a BEP on an enlarged scale showing the table positioned between its retracted and deployed positions; and 
     FIG. 6 is a detailed cross sectional view of a portion of FIG. 3 on an enlarged scale. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 1 shows a cross sectional view looking down on a building entry protection unit (BEP) 1 shown in the open position as it would be accessed by a technician during servicing. BEPs are commonly used to connect telephone lines within a building to the external lines of a regional telephone system. BEPs typically contain wiring blocks, connectors, and electrical surge protection equipment, and can also house optical fiber junctions as well as other components. BEP 1 comprises a housing 2, a cover 3 which swings on a hinge 4, and an inner door 5 which swings on a hinge 6. Both the inner door 5 and the housing 2 contain the various components of the BEP which a technician will service. Housing 2 has a mounting surface 7 located at the bottom of the housing. 
     A pivotable table 10 is shown mounted within BEP 1, table 10 comprising a table member 12 which is a substantially flat plate 13. Plate 13 has an end surface portion or flange 14, best seen in FIG. 4, comprising a curved segment 16 which extends from plate 13 through an arc of approximately 90°, and a straight segment 18 which extends from curved segment 16 and is oriented substantially perpendicular to plate 13. It is advantageous to provide sidewalls 46 entirely around the perimeter of plate 13. Sidewalls 46 extend substantially perpendicular to the plane of plate 13 and form a trough which prevents components on the table member from sliding or rolling off of the table member and being lost on the ground. 
     Although pivotable table 10 is shown in conjunction with a BEP, it is understood that the invention is not limited to this use and that table 10 could be used in conjunction with a wide range of housings, junction boxes and other devices or structures. 
     Hinge brackets 20 are mounted to plate 13, a plurality of hinge brackets 20 being shown and preferred, but it being understood that a single hinge bracket could also suffice. As seen in FIG. 4, each hinge bracket 20 preferably comprises a mounting flange 22 which provides an interfacing surface for attachment of hinge bracket 20 to plate 13. Any manner of attachment is possible, for example, by bolts, welding or adhesive as are commonly known in the art. Extending from each mounting flange 22 is a pair of gussets 24 which provide a mount for a hinged attachment. Through the gussets 24 are apertures 26 through which an axle 28 passes for rotational motion. 
     The flange 14 of table member 12 is disposed adjacent to a mounting assembly which preferably comprises a plurality of bosses 30 which are attached to housing 2, preferably near the bottom of the housing on or adjacent to the mounting surface 7 as seen in FIGS. 2 and 3. Although a plurality of bosses are preferred and shown, a single boss could be used. As best seen in FIGS. 4 and 5, each boss 30 is arranged opposite from one of the hinge brackets 20 and includes a surface 32 which faces the oppositely sited hinge bracket 20. An aperture 34 passes through each surface 32. The mounting assembly further comprises one or more elongated retention pins 36, a pin extending from each boss 30, each pin passing through a respective aperture 34. Pins 36 are slidably housed within each respective boss. One end of each pin 36 is pivotally attached to the hinge bracket 20 opposite the boss in which the pin is housed, pins 36 being rotatably attached via respective axles 28. The other end of each pin 36 has an enlarged head 38 best seen in FIG. 5. One or more biasing members are operatively associated with the mounting assembly, the biasing members preferably comprising coil springs 40. Each spring 40 is disposed coaxially about each pin 36 and trapped between enlarged head 38 and inner surface 32a of boss 30 opposite surface 32. Each spring 40 is compressed between a head 38 and an inner surface 32a of a boss 30 to provide biasing forces urging table member 12 toward the bosses 30. 
     When the table is in the retracted position as seen in FIG. 3 and in detail in FIG. 4, biasing forces from springs 40 acting through pins 36 urge an edge 18a of straight segment 18 against surfaces 32 of bosses 30. The biasing forces and the impingement of edge 18a against boss surfaces 32 creates torque or twisting force which tends to keep table member 12 in its retracted position. Sidewall 46 located at the end 42 of table member 12 impinges on a similar boss structure 43 to prevent table member 12 from further rotating. 
     However, table member 12 can be pivoted into the extended position as seen in the sequence of FIGS. 4, 5 and 6. To extend table member 12 a traction force is applied at the end 42 of table member 12 opposite the hinge brackets 20, thereby pulling the end 42 of table member 12 outwardly from housing 2. Table member 12 pivots about axles 28 drawing pins 36 outwardly from bosses 30 and compressing springs 40 between heads 38 and boss portions 32a. Edge 18a rides upwardly along surfaces 32 as seen in FIG. 5. Preferably, edge 18a is rounded so as not to gouge surfaces 32 and allow table member 12 to pivot smoothly. Curved segment 16 also facilitates the smooth pivoting of table member 12 as readily seen in FIG. 5 where the curved shape of segment 16 passes easily and naturally over mounting surface 7 of housing 2. 
     Once table member 12 has pivoted into the extended position as seen in FIG. 2 and in detail in FIG. 6, biasing forces from springs 40 draw table member 12 toward bosses 30 so that the outer surface region 18b of straight segment 18 is brought into contact with surfaces 32 of bosses 30. Straight segment 18 has cutouts 44 which allow pins 36 to pass through straight segment 18 which is preferably substantially continuous except for the cutouts. Table member 12 is maintained in its extended position at substantially a right angle to housing 2 by the biasing forces drawing outer surface region 18b against surfaces 32 as well as pins 36 impinging on straight segment 18 at the bottom 44a of cutouts 44. 
     With table member 12 in the extended position as seen in FIG. 2 the technician servicing BEP 1 has a convenient table on which to place tools and components and to perform tasks such as polishing and splicing optical fibers, using a wire wrap gun and the like. 
     It is preferred to construct the table member from sheet metal, although other materials, e.g., plastic materials such as PVC, would also serve equally well. 
     When the technician has completed his tasks table member 12 can be easily pivoted into its retracted position within BEP 1, out of the way but conveniently ready for use the next time the BEP needs servicing. Incorporation of a pivotable work table according to the invention in BEPs and other types of junction boxes or devices provides clear advantages to technicians servicing the device and eliminates the need for the technician to bring a separate table, in addition to the tools and components which he will need to perform his tasks.