Abstract:
A modular display system of interlocking components, and more particularly, a modular cubic display frame, comprising two sets of four mitered frame members, the two sets defining opposing rectangular end planes, and a set of longitudinal frame members extending perpendicularly between the corners of the two end planes. The end and the longitudinal frame members are interconnected at each corner utilizing a threaded bolt or screw having a lipped head. The lip projecting from the head engages a corresponding groove formed in the outer surfaces of the mitered corners of the end frame members, while the externally-threaded shaft of the screw engages an internally-threaded bore in the end of the longitudinal frame member. All of the frame members have longitudinal channels formed along each side and one corner, for attaching two modular display frames to each other, or for attaching a variety of auxiliary devices to a display frame. The channels are identical in size and configuration, having a T-shaped cross-section. The display frames are joined to each other by connecting strips configured to be matingly received in the channels; that is, the strips have I-shaped cross-sections.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to U.S. provisional application No. 60/031,869, filed Nov. 27, 1996, abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to modular display systems. More specifically, the invention relates to modular display systems, the basic modules of which are interlocking cubes adapted to received ancillary devices. 
     2. Related Art 
     Corner connection systems are disclosed in U.S. Pat. Nos. 3,912,410; 4,501,512; 4,021,128; and 3,835,354. The concept of providing longitudinal channels along frame members, for attaching various accessories, is disclosed in U.S. Pat. Nos. 3,399,856; 3,613,897; 5,255,803, and 5,477,594. Various interconnection systems using a member of I-shaped cross-section are disclosed in U.S. Pat. Nos. 3,425,721; 5,090,835; and 5,149,236. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a modular display system of interlocking components, and more particularly, a modular cubic display frame, comprising two sets of four mitered frame members, the two sets defining opposing rectangular end planes, and a set of longitudinal frame members extending perpendicularly between the corners of the two end planes. The end and the longitudinal frame members are interconnected at each corner utilizing a threaded bolt or screw having a lipped head. The lip projecting from the head engages a corresponding groove formed in the outer surfaces of the mitered corners of the end frame members, while the externally-threaded shaft of the screw engages an internally-threaded bore in the end of the longitudinal frame member. 
     All of the frame members have longitudinal channels formed along each side and one corner, for attaching two modular display frames to each other, or for attaching a variety of auxiliary devices to a display frame. The channels are identical in size and configuration, having a T-shaped cross-section. The display frames are joined to each other by connecting strips configured to be matingly received in the channels; that is, the strips have I-shaped cross-sections. 
     Auxiliary devices such as crossbars, hang rods, legs, shelves, panels, doors, and drawers can be attached to a display frame using specially configured connectors which are selectively lockable into the channels. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is better understood by reading the following Detailed Description of the Preferred Embodiments with reference to the accompanying drawing figures, in which like reference numerals refer to like elements throughout, and in which: 
     FIG. 1 is a perspective view of a cube module of the modular display system in accordance with the present invention. 
     FIG. 2 is a cross-sectional view of a frame member of the cube module of FIG. 1, taken along line 2--2 of FIG. 1. 
     FIG. 3A is an elevational view, partially in cross-section, of a connector for connecting frame members of the type shown in FIG. 2 to form the cube module of FIG. 1. 
     FIG. 3B is a top plan view of the connector of FIG. 3A. 
     FIG. 4A is an exploded plan view of three frame members of the type shown in FIG. 2 arranged to form a corner of a cube module, and the connector of FIG. 3A. 
     FIG. 4B is a cross-sectional view of FIG. 4A, taken along line 4B--4B. 
     FIG. 5A is an assembled view of the three frame members and the connector shown in FIG. 4A. 
     FIG. 5B is a cross-sectional view of FIG. 5A, taken along line 5B--5B. 
     FIG. 6A is a cross-sectional view of a connecting strip for connecting two cube modules of the type shown in FIG. 1. 
     FIG. 6B is a cross-sectional view similar to FIG. 6A, interlocked with the frame members of two cube modules, the frame members being shown in dashed lines. 
     FIG. 7A is an end elevational view of a clip for attaching wiring to the module of FIG. 1, in the uncompressed state. 
     FIG. 7B is a side elevational view of the clip of FIG. 7A. 
     FIG. 7C is a side elevational view of the clip of FIG. 7A, in the compressed state. 
     FIG. 8A is a front elevational view of a panel assembly for insertion into a side of the module of FIG. 1. 
     FIG. 8B is a side elevational view of a panel holder of the panel assembly of FIG. 8A. 
     FIG. 8C is a front elevational view of the panel holder of FIG. 8B. 
     FIG. 8D is a cross-sectional view of the panel holder, taken along line 8D--8D of FIG. 8B. 
     FIG. 8E is a cross-sectional view of the panel holder, taken along line 8E--8E of FIG. 8C. 
     FIG. 9A is an end plan view of a door hinge attached to a frame member of the type shown in FIG. 2, with the hinge in the closed position, the door being shown in dashed lines. 
     FIG. 9B is an end plan view of the door hinge and frame member of FIG. 9A, with the hinge in the open position, and the door being shown in dashed lines. 
     FIG. 10A is an elevational view, partially in cross-section of a crossbar for attachment between two frame members of the module of FIG. 1. 
     FIG. 10B is a partial cross-sectional view of the crossbar of FIG. 10A shown connected to a frame member. 
     FIG. 10C is a side elevational view of a screw for locking the crossbar of FIG. 10B into the channel of a frame member as shown in FIG. 10B. 
     FIG. 10D is a top plan view of the screw of FIG. 10C. 
     FIG. 10E is an end elevational view showing the screw of FIG. 10C inserted into a channel. 
     FIG. 10F is an end elevational view of a threaded disk to be screwed onto the shaft of the screw of FIG. 10C, as shown in FIG. 10B. 
     FIG. 10G is a cross-sectional view of the disk of FIG. 10F, taken along line 10G--10G of FIG. 10F. 
     FIG. 10H is a cross-sectional view of the disk of FIG. 10F, taken along line 10H--10H of FIG. 10F. 
     FIG. 10I is a locking ring for locking the disk of FIG. 10F onto the crossbar of FIG. 10A, as shown in FIG. 10B. 
     FIG. 10J is a cross-sectional view of the locking ring of FIG. 10I, taken along line 10J--10J of FIG. 10I. 
     FIG. 10K is a cross-sectional view of a screw for holding the locking ring of FIG. 10I onto the end of the crossbar of FIG. 10A, as shown in FIG. 10B. 
     FIG. 11A is an elevational view, partially in cross-section of a U-shaped hanging rod for attachment between two frame members of the module of FIG. 1. 
     FIG. 11B is a partial cross-sectional view of the hanging rod of FIG. 11A shown connected to a frame member. 
     FIG. 12 is an elevational view, partially in cross-section of a faceout rod for attachment to a frame member of the module of FIG. 1. 
     FIG. 13A is a side elevational view, partially in cross-section of a shelf assembly for mounting on the faceout rod of FIG. 12. 
     FIG. 13B is a top plan view of the shelf assembly of FIG. 13A. 
     FIG. 13C is a top plan view of the mounting bracket of the shelf assembly of FIG. 13A. 
     FIG. 13D is a cross-sectional view of the mounting bracket, taken along line 13D--13D of FIG. 13C. 
     FIG. 13E is a cross-sectional view of the mounting bracket, taken along line 13E--13E of FIG. 13C. 
     FIG. 13F is a top plan view of a module having the faceout rod of FIG. 12 attached thereto and the shelf assembly of FIG. 13B mounted on the faceout rod. 
     FIG. 14A is a top plan view of a shelf support pin for attachment to a frame member of the module of FIG. 1. 
     FIG. 14B is a cross-sectional view of the shelf support pin of FIG. 14A, taken along line 14B--14B of FIG. 14A. 
     FIG. 14C is an enlargement of the circled area 14C of FIG. 14A. 
     FIG. 15A is a side elevational view of a pair of modules of the type shown in FIG. 1, with legs attached to the bottom of the bottommost module. 
     FIG. 15B is a side elevational view of one of the legs shown in FIG. 15A. 
     FIG. 15C is a side elevational view of a single module as shown in FIG. 1, with legs attached to the bottom of the module. 
     FIG. 15D is a side elevational view of one of the legs shown in FIG. 15C. 
     FIG. 16A is an elevational view of an attachment rod for attaching a centered crossbar to the exterior of the module of FIG. 1. 
     FIG. 16B is an elevational view, partially in cross-section, of the attachment rod of FIG. 16A, rotated 90°. 
     FIG. 16C is a partial elevational view of the attachment rod of FIG. 16A attached to the exterior of a module. 
     FIG. 16D is a top plan view of a screw for attaching the attachment rod to a frame member of the module. 
     FIG. 16E is a cross-sectional view of the screw of FIG. 16D, taken along line 16E--16E of FIG. 16D. 
     FIG. 16F is an end elevational view showing the screw of FIG. 16D inserted into a channel. 
     FIG. 16G is an top plan view of a threaded ring for holding the screw of FIG. 16D In place in the attachment rod of FIG. 16A. 
     FIG. 16H is a cross-sectional view of the threaded ring of FIG. 16G, taken along line 16H--16H of FIG. 16G. 
     FIG. 17A is an elevational view of a crossbar for attachment between two attachment rods of the type shown in FIG. 16A, with the attachment rods being shown in dashed lines. 
     FIG. 17B is an elevational view, partially in cross-section, of the attachment rod of FIG. 16A, rotated 90°, with the attachment rods being shown in dashed lines. 
     FIG. 18A is a front elevational view of the module of FIG. 1 with a set of drawers therein. 
     FIG. 18B is a front elevational view of one of the drawers shown in FIG. 18A. 
     FIG. 18C is a side elevational view of the drawer of FIG. 18B. 
     FIG. 19A is a front elevational view, partially-exploded, of the module of FIG. 1 with a pair of panel holders. 
     FIG. 19B is a top plan view of one of the panel holders of FIG. 19A. 
     FIG. 20A is a side elevational view, partially in cross-section, of a connector for connecting various devices to a frame member. 
     FIG. 20B is an end plan view of the male fitting of the connector of FIG. 20A. 
     FIG. 20C is a side elevational view, partially in cross-section, of the male fitting of FIG. 20B. 
     FIG. 20D is an end plan view of the adjusting ring for the male fitting of the connector of FIG. 20A. 
     FIG. 20E is a side elevational view, partially in cross-section, of the adjusting ring of FIG. 20D. 
     FIG. 20F is a top plan view of the screw for attaching the connector to a frame member of the module. 
     FIG. 20G is a cross-sectional view of the screw of FIG. 20F, taken along line 20G--20G FIG. 20F. 
     FIG. 20H is an end elevational view showing the screw of FIG. 20F inserted into a channel. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In describing preferred embodiments of the present invention illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the invention is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. 
     Referring now to FIG. 1, there is shown a cube module 10 of the modular display system in accordance with the present invention. The cube module 10 comprises two end frames 12 of four end frame members 14a, and four side frame members 14b joining the two end frames 12. The twelve frame members 14a and 14b thus define the edges of the cube. Although the module 10 is referred to as a cube, it will be appreciated that by elongating any four parallel frame members 12 relative to the remaining parallel members 12, the module 10 can be configured as a rectangular prism, rather than a cube, without substantially affecting the function of the invention. 
     As can further be seen from FIG. 1, and as will be discussed in greater detail hereafter, the ends of the end frame members 14a are mitered at their joints with each other, while the ends of the side frame members 14b are squared off at their joints with the corners of the end frames 12. Otherwise, end frame members 14a and side frame members 14b are essentially identical frame members 14 having a unique cross-section, shown in FIG. 2, which enables individual modules 10 to be joined together, as will also be discussed in greater detail hereafter. 
     Referring now to FIG. 2, it can be seen that each frame member 14 has a cross-section which is a soft square (that is, a square with rounded edges), interrupted by five channels 20 of T-shaped cross-section and identical dimensions. The edges of all of the channels 20 are radiused. 
     Two channels 20a are formed in adjacent first and second sides S1 and S2 of the frame member 14 centered between the first and second edges E1 and E2 and between the second and third edges E2 and E3 of the adjacent first and second sides S1 and S2 of the frame member 14, two channels 20b are adjacent the first and third edges E1 and E3 between the first and fourth sides and between the second and third sides, respectively, and a fifth channel 20c is formed on the fourth edge E4 between the third and fourth sides S3 and S4, thus effectively cutting off the fourth edge E4. One side edge of each second channel 20b aligns with the center line of the first channel 20a on the opposite side of frame member 14. Each frame member 14 is symmetric about a diagonal plane through the second edge E2 and center C. When the frame members 14 are assembled to form a module 10, the third channel 20c is oriented toward the interior of the module 10. 
     Referring now to FIGS. 3A, 3B, 4A, 4B, 5A, and 5B, there is shown a connector 30 for connecting the end frame members 14a and side frame members 14b together to form a module 10 in accordance with the invention. As shown in FIGS. 3A and 3B, connector 30 is a screw having a head 32 and a shaft 34. Head 32 has an axial recess 32a in its upper surface for receiving the mating head of a wrench, and an annular tapered lip 32b projecting from its lower surface, while the shaft 34 is conventionally provided with external threads. 
     As shown in FIGS. 4A, 4B, 5A, and 5B, at each corner of the module 10, the mitered ends of end frame members 14a are bored to matingly receive the screw 30, the bores having an inner portion 40a with a smaller radius corresponding to that of the screw shaft 34 and an outer portion 40b with a larger radius corresponding to that of the screw head 32. The outer portion 40b is provided with a tapered circumferential groove 40c for matingly receiving the tapered lip 32b of the screw 30. Further, the squared off end of the side frame member 14b is provided with an internally-threaded axial bore 42 for matingly receiving the externally-threaded shaft 34 of the screw 30. 
     Preferably, frame members 14 and screws 30 are made of aluminum. However, it will be appreciated by those of skill in the art that other metals, as well as plastics, can also be used. 
     Referring now to FIGS. 6A and 6B, there is shown a connecting strip 50 for connecting two modules 10. Connecting strip 50 preferably is made of a plastic material such as PVC, although other materials having similar characteristics of flexibility, resilience, and durability can also be used. 
     The connecting strip 50 has an I-shaped cross-section with radiused edges, dimensioned to be matingly received in the channels 20 of the frame members 14, as shown in FIG. 6B. Although the frame members 14 in FIG. 6B are shown joined along two sides, it will be appreciated by those of skill in the art that as all of the channels 20 are of the same dimension, any two frame members 14 can also be joined corner to corner or side to corner, as well. Thus, the modules 10 can be jointed together in a variety of configurations simply by connecting their adjacent frame members 14 using the connecting strips 50. 
     In addition to providing a means for connecting adjacent modules 10 together, channels 20 can also be used for attaching a variety of ancillary or auxiliary devices to the frame members 14. Some of these devices are shown in the remaining Figures. 
     FIGS. 7A and 7B show a clip 102 designed to secure wiring to the frame members 14. The clip is formed of a flexible and resilient material, such as a soft steel, so that its legs 102a can be pressed together, enabling the feet 102b extending outwardly from the legs 102a to be inserted into a channel 20. 
     FIGS. 8A, 8B, and 8C show a panel assembly 104 and the components thereof intended for insertion into the sides or ends of a module 10. As shown in FIG. 8A, the panel assembly 104 comprises a panel 104a and four panel holders 104b secured along two sides of the panel 104a. The panel holders 104b can be made of a soft steel. 
     Each panel holder 104b has a slot 104c at one end for receiving an edge of the panel 104a and a spring-loaded bearing 104d at the other end for insertion into a channel 20. The slot 104c can be provided with pads 104e, to prevent scratching of the panel 104a and a screw 104f for tightening against the panel 104a to hold it in place in the slot 104c. The tension of the spring-loaded bearings 104d is adjusted so that they can be retracted easily to permit insertion or removal of the assembly 104 with respect to a side of the module 10, with the bearings 104d extending into the channels 20 when the assembly is in place. The panel 104a can be in the form of a mirror, a transparent or semi-transparent window, or opaque. 
     FIGS. 9A and 9B show a door hinge 110a for attaching a door 110b to one of the frame members 14 of a module 10. The door hinge 110a comprises a pin portion 110c and a barrel portion 110d, both preferably made of aluminum. The pin portion 110c in turn includes a cylindrical pin 110e and a connector 110f of T-shaped cross-section projecting outwardly from the pin 110e and dimensioned to be matingly received in one of the channels 20 of a frame member 14; while the barrel portion 110e includes at one end a channel 110g of generally C-shaped cross-section for pivoting engagement with the pin 110e, and at the other end a groove 110h of generally U-shaped cross-section for receiving an edge of the door 110b. 
     Referring now to FIGS. 10A-10K, there is shown a crossbar 120 for positioning between two frame members 14 of a module 10, and a locking assembly 122 for locking the crossbar 120 in place in the channels 20 of the two frame members 14. 
     As shown in FIGS. 10A, 10B, and 10K, the crossbar 120 has two axial end bores 120a, for a purpose to be discussed hereinafter. Crossbar 120 preferably is made of aluminum, but can also be made of other materials of suitable strength to serve as a crossbar. 
     A screw 122a is provided for locking the crossbar 120 into the channel 20. As shown in FIGS. 10C-10D, the screw 122a has a trapezoidal head 122b and a threaded shaft 122c, the head 122b being dimensioned to be insertable into and removable from the channel 20 when oriented in one direction and locked into the channel 20 when rotated 90° from that direction. 
     FIGS. 10F-10H show a threaded disk 122d, which can be made of brass, to be screwed onto the shaft of the screw of FIG. 10C, as shown in FIG. 10B. FIG. 10I in turn shows a locking ring 122e for locking the disk 122d onto the crossbar 120, as shown in FIG. 10B, and the locking ring 122e is held in place against the end of the crossbar 120 by a flat head screw 122f screwed into the bore 120a, as shown in FIGS. 10B and 10K. Locking ring 122e can be made of aluminum. 
     As will be appreciated by those of skill in the art, the locking assembly 122 can also be used to position the crossbar 120 between the frame members 14 of two spaced modules 10, in the same way as between two parallel frame members 14 of a module 10. 
     Referring now to FIGS. 11A and 11B, there is shown a U-shaped hanging rod 130 and a locking assembly 122 for locking the hanging rod 130 in place in the channels 20 of the frame members 14 of a module 10, the locking assembly 122 being the same as that described with reference to FIGS. 10B-10K. Like crossbar 120, hanging rod 130 has axial end bores 130a, each of which receives a screw 122f which locks the locking assembly 122 in place, and can be made of the same materials as the crossbar 120. Also as with the crossbar 120, the locking assembly 122 can be used to position the hanging rod 130 between the frame members 14 of two spaced modules 10, in the same way as between two parallel frame members 14 of a module 10. 
     FIG. 12 shows a faceout rod 140 for attachment to a frame member 14 of the module 10 using the locking assembly 122 described with reference to FIGS. 10B-10K. Faceout rod 140 has an axial end bore 140a at one end, which receives a screw 122f which locks the locking assembly 122 in place. At its other end, faceout rod 140 has a knob 140b, which is connected to the body of the rod by a necked-in area 140c. Faceout rod 140 can also be made of the same materials as the crossbar 120. 
     As will be appreciated by those of skill in the art, the faceout rod 140 can be positioned in a channel 20 either facing the interior or the exterior of the module 10. 
     Referring now to FIGS. 13A-13E, there is shown a shelf assembly 150 for mounting on the faceout rod 140. The shelf assembly 150 comprises a shelf 152 and a mounting bracket 154 which holds the shelf 152. Both the shelf 152 and the mounting bracket can be made of aluminum, although it will be appreciated by those of skill in the art that other materials can be used. 
     The shelf 152 can be configured and dimensioned to fit within the interior of the module 10. The mounting bracket 154 is in the shape of an inverted, truncated cone, and has both an axial bore 154a and a transverse bore 154b at a right angle to the axial bore 154a. The transverse bore 154b is dimensioned to receive the faceout rod 140. The shelf 152 has a central, counterbored aperture 152a, enabling a flat head screw (not shown) to be inserted through the shelf and the axial bore 154a to secure the shelf 152 to the mounting bracket 154. The faceout rod 140 can also be provided with a transverse bore (not shown) in registration with the axial bore 154a of the mounting bracket 154, to enable the flat head screw to pass through, or the screw can be dimensioned to be tightened against the surface of the faceout rod 140. 
     FIG. 13F shows a module 10 having the faceout rod 140 inserted into a corner channel 20c of a side frame member 14b, and the shelf assembly 150 mounted on the faceout rod 140. 
     FIGS. 14A-14C show a shelf support pin 160 for attachment to a frame member 14 of the module 10 using the locking assembly 122 described with reference to FIGS. 10B-10K. Shelf support pin 160 has an axial end bore 160a at one end, which receives a screw 122f which locks the locking assembly 122 in place. At its other end, shelf support pin 160 is provided with a radiused circumferential groove 160b. Four of these shelf support pins 160 can be inserted into the interior channels 20 of the side frame members 12b at the same level to provide support for a shelf in a conventional manner. The shelf support pin 160 can be made of aluminum or other suitable materials. 
     A module 10 can be mounted on legs 170 to raise it above floor level, as shown in FIGS. 15A and 15C. The height of the legs 170 used with a module 10 or a stack of modules will, as is conventional, depend upon the height to which it is desired to raise the module or stack of modules. Legs 170 of two different heights are shown in FIGS. 15A and 15B, and in FIGS. 15C and 15D, the legs 170 of FIG. 15A and 15B having a height equal to that of one module 10, and the legs 170 of FIGS. 15C and 15D having a height equal to that of two modules 10. 
     Other than their heights, the legs 170 are identical. Each leg 170 has a shaft portion 170a, a foot 170b at the bottom of the shaft portion 170a, and an integral screw 170c at the top of the shaft portion 170a. The screw 170c has substantially the same configuration as the screw 30 described in connection with FIGS. 3A and 3B, enabling the legs 170 to replace the screws 30 at the bottom of the module 10. Thus, the upper surface of the shaft portion 170a has an annular tapered lip 170c projecting from its upper surface for mating engagement with the tapered circumferential groove 40c provided in the bottom surfaces of the end frame members 14a; and an externally-threaded shaft portion 170d dimensioned for engagement with the internally-threaded bore 42 of the side frame members 14b. 
     Referring now to FIGS. 16A-16H, there is shown a cylindrical attachment rod 180 for attaching a centered crossbar 190 (to be described hereafter) to the exterior of a module 10. Attachment rod 180 has two end transverse bores and a center transverse bore 180b. The longitudinal axes of transverse bores 180a and 180b are parallel. Transverse bores 180a have constant diameters throughout their lengths; whereas transverse bore 180b has a first end having a first diameter and a second end having a second diameter greater than the first diameter, for a purpose to be described hereafter. Attachment rod 180 can be made from aluminum or other suitable materials. 
     Attachment rod 180 is attached to a frame member using a pair of screws 182, shown in FIGS. 16D-16F, inserted through end bores 180a and into a channel 20 in the manner shown in FIG. 16C. As shown in FIGS. 16D-16F, each screw 182 has a trapezoidal head 182a and a threaded shaft 182b, the head 182a being dimensioned to be insertable into and removable from the channel 20 when oriented in one direction and locked into the channel 20 when rotated 90° from that direction. 
     A ring 184 having a knurled circumference 184a and an internally-threaded bore 184b engages the exposed end of the threaded shaft 182b, is provided for securing the attachment rod 180 in place on screws 182 and against the frame member 14 of the module 10. The ring 184 can also be made of aluminum. 
     A pair of attachment rods 180 can be attached to a respective pair of spaced modules 10 to receive a centered cylindrical crossbar 190 between them, as shown in FIGS. 17A and 17B. The crossbar 190 has semi-cylindrical channels 190a formed at either end, dimensioned to engage the side surfaces of the two attachment rods 180; and internally-threaded axial bores 190b extending inwardly from the channels 190a. The crossbar 190 is held in place between the two attachment rods 180 by two screws 192 inserted into the center bores 180b of the attachment rods 180 and the axial bores 190b of the crossbar 190, the larger diameter portion of each center bore 180b being dimensioned to receive the head of a screw 192; and the smaller diameter portion of each center bore being the same diameter as its corresponding axial bore 180b and being dimensioned to receive the shaft of a screw 192. The crossbar 190 can also be made of aluminum or other suitable materials. 
     As shown in FIG. 18A, a set of drawers 200 can be installed in a module 10. In one embodiment, shown in FIGS. 18B-18C, each drawer 200 has a cutout 200a at its front top for use as a drawer pull, and at its sides, conventional ball bearing and wheel type drawer slides 200b. Conventional mating slides (not shown) for engaging the slides 200b can be mounted between the side frame members 14b using an attachment rod similar to that shown in FIGS. 16A-16B, but having the mating slides attached to the sides. 
     As shown in FIGS. 19A-19B, a pair of panel holders 210 can be installed on the top of a module 10, to hold a display panel P. Each panel holder 210 has a C-shaped cross-section, one edge of the panel P fitting into the channel 210a defined by the &#34;C.&#34; 
     Each panel holder 210 also has an integral screw 210b at its bottom end. The screw 210b has substantially the same configuration as the screw 30 described in connection with FIGS. 3A and 3B, enabling the panel holders 210 to replace the screws 30 at the top of the module 10. Thus, the lower surface of the panel holder 210 has a circumferential tapered lip 210c projecting from its lower surface for mating engagement with the tapered circumferential groove 40c provided in the upper surfaces of the end frame members 14a, and an externally-threaded shaft portion 210d dimensioned for engagement with the internally-threaded bore 42 of the side frame members 14b. 
     As will be appreciated by those of skill in the art, it may be desirable to attach numerous other ancillary accessories and articles to a module 10. A universal connector 220 therefore is provided, as shown in FIG. 20A. Referring to FIGS. 20A-20C, the connector 220 includes a bushing 220a for receiving the end of the article to be to a frame member 14. The bushing 220a has an axial bore at one end dimensioned to receive an end of the article, and another axial bore at the other end dimensioned to receive a male fitting 220b, shown in FIGS. 20B and 20C. The bore which receives the end of the article can be threaded or unthreaded, depending upon the application. The bore which receives the male fitting 220b is internally threaded. 
     The male fitting 220b has a head 220c which is knurled around its circumference and a shaft 220d which is externally threaded. Further, an internally-threaded axial bore extends through the head 220c and the shaft 220d for receiving a screw 220e for attaching the connector 220 to a frame member 14 of the module 10. As shown in FIGS. 20F-20H, the screw 220e has a trapezoidal head 220f and a threaded shaft 220g, the head 220f being dimensioned to be insertable into and removable from the channel 20 when oriented in one direction and locked into the channel 20 when rotated 90° from that direction. 
     The position of the male connector 220b relative to the bushing 220a is conventionally adjusted using an adjusting ring 220h, shown in FIGS. 20D and 20E. Adjusting ring 220h is also knurled on its circumference, and has an internally-threaded axial bore dimensioned to receive the shaft 220g of the screw 220e. 
     Both the male fitting 220b and the adjusting ring 220h can be made of aluminum or other suitable materials. 
     Modifications and variations of the above-described embodiments of the present invention are possible, as appreciated by those skilled in the art in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims and their equivalents, the invention may be practiced otherwise than as specifically described