computer controlled display screens provide drivers factory

Computer-controlled display screens provide drivers in the Indianapolis 500 with a variety of information about how their cars are performing. For instance, as a car is going through a turn, a speed of 237 mi/h (105.939 m/s) and a centripetal acceleration of 3.00g (three times the acceleration due to gravity) are displayed. Determine the radius of the turn.

[0154] An apparatus and method for supporting flat panel display devices is disclosed. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that these specific details need not be used to practice the present invention. In other circumstances, well-known structures, materials, or processes have not been shown or described in detail in order not to unnecessarily obscure the present invention.

[0155] FIG. 1E depicts one embodiment of a conventional computer system that may be used with a display device as described herein. The computer system 151 interfaces to external systems through a modem or network interface 167. It will be appreciated that the modem or network interface 167 may be considered part of computer system 151. This interface 167 may be an analog modem, an ISDN modem, a cable modem, an Ethernet interface, a satellite transmission interface (e.g. Direct PC), or other network interface for coupling a digital processing system to other digital systems (e.g. the interface 167 couples computer system 151 to a local computer network or to the internet).

[0156] The computer system 151 includes a processor 153 which may be a conventional processor, such as a Motorola Power PC microprocessor or an Intel Pentium microprocessor. Memory 155 is coupled to processor 153 by the bus 157. Memory 155 may be dynamic random access memory (DRAM) and may also include static RAM (SRAM). The bus 157 couples the processor 153 to the memory 155 and also to mass memory 163 and to display controller 159 and to the I/O (input/output) controller 165. Display controller 159 controls in the conventional manner a display on the FPDD 161, which may be a liquid crystal display device or other flat panel display device (e.g. organic light emitting diode display, vacuum fluorescent on silicon display, field emissive display, plasma display, etc.). The display controller 159 is coupled to the display 161 through a cable 160, which in one embodiment provides display data and power and control signals between the display 161 and the display controller 159.

[0157] The input/output devices 169 may include a keyboard, disk drives, printers, a scanner, a digital camera, and other input and output devices, including a mouse or other pointing device. The display controller 159 and the I/O controller 165 may be implemented with conventional well-known technology. The mass memory 163 is often a magnetic hard disk, an optical disk, or other form of storage for large amounts of data. Some of this data is often written, by a direct memory access process, into memory 155 during the execution of software in the computer system 151. It will be appreciated that the computer system 151 is one example of many possible computer systems which have different architectures. For example, Macintosh or Wintel systems often have multiple buses, at least one of which may be considered to be a peripheral bus.

[0158] Network computers may also be considered to be a computer system which may be used with the various display devices described herein. Network computers may not include a hard disk or other mass storage, and the executable programs are loaded from a network connection (e.g. through network interface 167) into the memory 155 for execution by the processor 153. A Web TV system, which is well-known in the art, may be considered to be a computer system according to the present invention, but it may not include certain features shown in FIG. 2B, such as certain input/output devices.

[0159] A cell phone, a personal digital assistant, or a digital camera having a suitable display interface (to couple to a display device as described herein) and a processor and memory may also be considered to be a digital processing system or a computer system which may be used with the present invention. A typical computer system will usually include at least a processor, a memory, and a bus coupling the memory to the processor. It will also be appreciated that computer system 151 is typically controlled by an operating system software which includes a file management system and a disk operating system.

[0160] Referring again to FIGS. 1E and 2A, in one embodiment of the invention, certain elements of the computer system 151 (e.g. processor 153, memory 155, bus 157, mass memory 163, display controller 159, I/O controller 165, an optical drive (not shown), and possibly also interface 167) are housed in a moveable enclosure 242A which is coupled to the base 242 of the moveable assembly (shown in FIGS. 2A-2D as moveable assembly 200). The opposite end of the moveable assembly is coupled with a FPDD (e.g. display 240, which corresponds to display 161). In this one embodiment, a cable is disposed within an interior portion of the moveable assembly 200 and couples the display 240 to the display controller 159, which provides display data to the display 240 through the cable 160. The cable may also provide power and the control signals (if any, such as brightness or contrast signals sent by an input device on the FPDD 240 to the system 151) to the FPDD 240.

[0165] In another embodiment, where moveable assembly 200 and/or display 240 are remotely (e.g. wirelessly or otherwise) coupled with moveable enclosure 242A, the base 242 of moveable assembly 200 may be clamped or otherwise fastened to a ground surface or an overhead surface. Base 242 of moveable assembly 200 may also be clamped or otherwise fastened to a substantially planar surface (e.g. desktop) or vertical surface (e.g. wall or side of a desk). Remote coupling may be accomplished using a wireless system or using extended lengths of power and data cables.

[0166] Still referring to FIG. 2A, moveable assembly 200 may be coupled with FPDD 240, as shown. Components of moveable assembly 200 may include: an actuator assembly 202, a display termination ball 222; a friction limit ball 226; a base 242; and a plurality of cables 234, including a tension cable, anti-torsion cable, data, microphone, power supply cables, and other cables.

[0167] As shown in FIG. 2A, actuator assembly 202 may be centrally and fixedly coupled with a backside of flat panel display device (FPDD) 240 using any of a number of suitable attachment methods (e.g. bolts, welds, adhesives, etc.) well-known in the art. Actuator assembly 202 is provided to reduce the amount of user force needed to collapse the moveable assembly. Typically, a user force of approximately 180 pounds to approximately 400 pounds is required. However, actuator assembly 202 reduces this force to an amount easily provided by an adult user (e.g. approximately 10.0 pounds to approximately 30.0 pounds). In the views of FIGS. 2A, 2B, 2C, 2D, 4A, and 4B, several of the ball-and-socket components are not shown in order to provide views of the cables which are within the ball-and-socket components.

[0169] In one embodiment, a proximal end of handle 241 may be shaped to include (or may be coupled with) a finger support member 260, which provides a first compression surface. Finger support member 260 may be made of the same or a different material that comprises the remainder of handle 241, and may take any suitable aesthetic or ergonomic shape, size, or contour. Similarly, a distal end of handle 241 may be pivotably coupled with one or more components of actuator assembly 202 such that handle 241 functions as a lever arm. As shown in FIG. 2A, handle 241 is angled away from the backside of FPDD 240 such that the proximal end of handle 241 is positioned near an edge of FPDD 240. In one embodiment, the edge may be the left-hand edge of FPDD 240 as viewed from the back (e.g. right-hand edge as viewed from the front).

[0173] Referring now to FIG. 2B, a back view of moveable assembly 200 is shown. In this view, it can be seen that display termination ball 222 and actuator assembly 202, in one embodiment, are positioned substantially in the center of the back of FPDD 240 in order to provide an axis of rotation substantially near FPDD 240"s center-of-mass. In other embodiments, display termination ball 222 and actuator assembly 202 may be non-centrally positioned on the back surface of FPDD 240. As shown in FIG. 2B, the outermost edge of handle 241 may be substantially coterminous with an edge of FPDD 240, or not.

[0176] It can be seen from FIGS. 2B, 2C, and 2D that the display surface area 240A of the FPDD 240 (which is usually most (e.g. more than 75%) of the surface area of the front surface of the FPDD) is substantially larger (e.g. at least 10 times larger) than a cross-sectional area of the moveable assembly 200 (which may be referred to as a neck). This cross-sectional area is a cross-section of the moveable assembly taken perpendicularly relative to the length of the moveable assembly (e.g. the cross section obtained at line 2D-2D shown in FIG. 2D). This cross-sectional area is typically a small fraction (e.g. about {fraction (1/50)} to about ⅙) of the display surface area 240A. It will be appreciated that the display surface area is the surface on which the display data (e.g. a graphical user interface such as the Macintosh OS X or Windows 2000) is displayed to a user of the computer system.

[0178] Referring now to FIG. 3, there is shown a diagram of exemplary torques and overturning moments associated with one embodiment of the invention. The three components of this embodiment, as shown in FIG. 3, are the base computer system 310A, the moveable assembly 310B, and the FPDD 310C. The base computer system 310A corresponds to the moveable enclosure 242A, and also includes a base which secures the moveable assembly 310B to the base computer system 310A. The base computer system 310A, in one embodiment, includes certain elements of the computer system (e.g. referring to FIG. 1E, a processor 153, memory 155, bus 157, mass memory 163, I/O controller 165, interface 167, and a CD-ROM drive or other types of optical drives) and is coupled electrically to the FPDD 310C through a power and data cable (or cables), which provides power to the FPDD 310C and provides data for display on the FPDD 310C (and optionally conveys data, such as control signals, from controls on the FPDD 310C to the computer system in the base computer system 310A. In one embodiment, such cable (or cables) are housed and concealed within the interior of moveable assembly 310B and are not normally visible to a user.

[0179] The moveable assembly 310B mechanically couples the base computer system 310A to the FPDD 310C. In one embodiment, this coupling is through a series of ball-and-socket joints which are held together by a tension cable within the ball-and-socket joints. The moveable assembly 310B is mechanically coupled to the base computer system 310A at a base end of the moveable assembly 310B and is mechanically coupled to the FPDD 310C at a display end of the moveable assembly 310B.

[0181] Using these exemplary measurements, together with an estimated distance 309 of approximately 13.29 inches, and an estimated distance 308 of approximately 6.64 inches, the upward force (Fu) 306 at the display needed to overturn the system is calculated to be approximately 9.25 pounds, while the downward force (Fd) 310 needed to overturn is calculated to be approximately 1.22 pounds. In one embodiment, distance 309 is measured from base center-of-mass to display center-of-mass. Similarly, distance 308 is measured from the base"s center-of-mass to the moveable assembly"s center-of-mass.

[0182] It will be appreciated that increasing the weight of the base will tend to improve the stability of the entire assembly. It is preferable that the base, and the rest of the assembly, should not be so heavy that it cannot be easily moved by a single human user (e.g. an adult user). For example, it is preferable that the whole assembly should be less than about 45 pounds (lbs) and have a footprint on the surface on which it rests of less than about four (4) square feet. Normally, the weight and size of the base (including the base computer system) are designed, as described herein, to counterbalance the weight of the moveable assembly and FPDD 310C so that the FPDD 310C can be selectively positioned at many possible positions (X, Y, Z, pitch, yaw, roll), and the whole assembly is still stable (e.g. does not tip or overturn). Thus, there is no need, normally, to require the base computer system to be fixedly attached to the surface on which it rests; no clamps or suction or adhesive are, in a preferred embodiment, normally needed to maintain stability of the entire assembly.

[0186] In one embodiment, the weight of the moveable assembly 200 shown in FIGS. 2A-2D is approximately 2.0 pounds (0.907 kg), including the balls, sockets, and cables. In one embodiment, the overall articulation length (as measured along a longitudinal dimension of the member 200) of moveable assembly 200 is approximately 15.5 inches (39.37 cm), and its maximum cantilever distance is approximately 13.5 inches (34.29 cm). The moveable assembly 200 provides the ability to move the FPDD in at least three degrees of freedom and preferably six degrees of freedom (X, Y, Z, pitch, yaw, and roll). Another example of a moveable assembly is described in U.S. patent application Ser. No. 10/035,417 entitled “COMPUTER CONTROLLED DISPLAY DEVICE,” filed Nov. 8, 2001, the contents of which are incorporated by reference herein.

[0191] On the other hand, because data, power, microphone, and other computer system-related cables are routed along the outer interior regions of the moveable assembly, it will be appreciated that the path length of these cables is not constant, but changes as the moveable assembly is twisted or bent. Accordingly, additional lengths of data, power, and communications cables may be provided to accommodate the path length change. Illustratively, the additional lengths may measure approximately 20% to 30% more than the straight line path length. The straight line path length is the path length measured from one end of the moveable assembly to the other when the moveable assembly is in a substantially straight, non-twisted, unbent position.

[0198] In one embodiment, the moveable enclosure has a weight in the range of approximately 12.0 pounds to approximately 13.0 pounds, with a footprint diameter of approximately 240.0 mm. It will be appreciated that the base is not limited to one particular size, weight, shape, or appearance. Rather, heavier bases may have smaller footprints, and vice versa. Additionally, the bottom surface of the moveable enclosure may be larger or smaller than the top surface. The bottom of the moveable enclosure may also be equipped with a non-slip surface. In one embodiment, the non-slip surface may be a tacky, spongy, rubber-like material. In another embodiment, the non-slip surface may be a rubber suction device. In a further embodiment, the non-slip surface may be a magnetic or electromagnetic device. Additionally, the base may be equipped with one or more input devices (e.g. push buttons, touch sensitive buttons, touch sensitive screens, etc.), peripheral ports, or peripheral devices (e.g. DVD and CD-ROM drives, speakers, etc.). As previously described, one or more components of a computer may be housed within the moveable enclosure.

[0205] Referring now to FIG. 4A, there is shown a cross-sectional top view of a moveable assembly 400, actuator assembly 400A, and FPDD 440, according to one embodiment of the invention. Tension cable 490 runs through central portions of balls 426 and terminates at the display end in a ball ferrule 434, which is coupled with distal end of handle 460. In another embodiment, ball ferrule 434 may be coupled with a crank (not shown), which is coupled with handle 460. In FIG. 4A, the distal end of handle 460 is coupled with a strut 409, which is coupled with a spring or piston assembly 470. The crank, handle 460, strut 409, and spring or piston assembly 470 are further described below.

[0207] Experiments performed to test the suitability of support mechanisms highlighted two significant drawbacks: substantial holding friction and the need to support the flat panel display device with one hand while manipulating the friction actuating device with the other. Although, gooseneck designs, such as a group of ball-and-socket joints, provide more degrees of freedom and a wider range of viewing positions than traditional support mechanisms, they require large amounts of holding friction to support heavy objects like flat panel display devices (FPDD"s) in stable positions. Typically, the amount of holding friction required is greater than an adult user can overcome (e.g. 180-400 lbs or more). In cases where the holding friction is of an amount (e.g. 20-30 lbs) that can be easily overcome by an adult user, the prior art gooseneck-like support mechanisms gradually droop, or suddenly fail altogether, causing damage to the FPDD.

[0212] Referring back to the embodiment shown in FIG. 4A, depressing proximal end 451A of handle 460 moves strut 409 laterally to compress spring/piston assembly 470. Simultaneously, the distal end of handle 460 moves upwards to relax the tension cable 490 and decompress the wave springs. Depressing proximal end 451A of handle 460 converts mechanical energy (e.g. that provided by the user depressing the handle 451) and potential energy (e.g. that stored in the tensioned cable and compressed wave springs) into kinetic energy as strut 409 moves laterally to compress spring/piston assembly 470 (e.g. 711 in FIG. 7A). This kinetic energy is converted into elastic potential energy, which is stored in the compressed spring/piston assembly 470. Likewise, releasing proximal end 451A of handle 451 converts the spring"s stored elastic potential energy into kinetic energy as strut 409 moves laterally to depress the distal end of handle 451. This kinetic energy is stored as potential energy in cable 490 is tensioned the wave springs as the moveable assembly is compressed.

[0217] In FIG. 4A, a display termination ball 424, having a substantially planar mating surface connects moveable assembly 400 to FPDD 440, but any suitable attachment method, such as bolts and/or interlocking grooves, may be used to attach display termination ball to FPDD 440. Anti-torsion cable 491 may be provided to prevent moveable assembly 400 from over-twisting and stretching the data, microphone, and/or the power supply cables.

[0220] Referring now to FIG. 5A, there is shown a side view of an assembled moveable assembly 500, including actuator assembly 502 (but without the FPDD and the base of the moveable assembly and the base computer display). In one embodiment, the length 551 of moveable assembly as measured from surface 503 of base termination ball 533 to surface 504 of display termination ball 522, measures approximately 397.00 mm.

[0224] FIG. 5E is a cross-sectional view of a portion 560 of a moveable assembly usable with an embodiment of the present invention showing the placement of data, tension, torsion, power, antenna, and other computer system related cables within one or more apertures 508, 512, 514, 504, 506, 520, and 516 of the moveable assembly. In one embodiment, portion 560 of the moveable assembly is a friction limit ball, having a wall (e.g. brace) containing a plurality of apertures (or bores) centrally located therein. Apertures 510, 516, and 520 are substantially circular in cross-section, while apertures 508, 514, 504, and 506 are irregularly shaped. Anti-torsion cables 512 and 518 extend through apertures 510 and 516, respectively, while torsion cable 590 extends through aperture 520. In one embodiment, one or more of the irregularly shaped apertures may include one or more data, power, antenna, and/or similar computer system-related cables.

[0225] As shown in FIG. 5E, aperture 508 includes an inverter cable 528 and a microphone cable 526, while aperture 514 contains a Transmission Minimized Differential Signaling (TDMS) cable 524. The inverter cable 528 powers the LCD flat panel display, while the TDMS provides data signals to the flat panel display. The TDMS cable is made up of four bundles of three wires each. Two wires within each bundle are twin-axial (e.g. helically twisted) signal wires, and the third wire is a drain wire. In one embodiment, the twin axial signal wires and drain wires are individually insulated with aluminum-mylar. Additionally, a plurality (in one embodiment, three) additional Extended Display Identification Data (EDID) wires may be included within TDMS cable 524 to provide additional signals to the flat panel display.

[0226] In an alternate embodiment, a Low Voltage Differential Signaling (LVDS) cable may be used. Low Voltage Differential Signaling is a low noise, low power, low amplitude method for high-speed (gigabits per second) data transmission over copper wire. LVDS differs from normal input/output (I/O) in a few ways: Normal digital I/O works with 5 volts as a high (binary 1) and 0 volts as a low (binary 0). When a differential is used, a third option (−5 volts), is added, which provides an extra level with which to encode and results in a higher maximum data transfer rate. A higher data transfer rate means fewer wires are required, as in UW (Ultra Wide) and UW-⅔ SCSI hard disks, which use only 68 wires. These devices require a high transfer rate over short distances. Using standard I/O transfer, SCSI hard drives would require a lot more than 68 wires. Low voltage means that the standard 5 volts is replaced by either 3.3 volts or 1.5 volts.

[0228] Referring now to FIG. 6, there is shown an exploded perspective view of a moveable assembly 600 and actuator assembly 602, according to one embodiment of the present invention. In one embodiment, tension cable 690 terminates at the actuator assembly end in a ball ferrule 634. Socket assembly 627 may be equipped with a wave spring (e.g. resilient member), plungers, and friction inserts, such that plungers supportably engaging friction limit ball 626 raise ball 626 from and lower ball 626 to a friction insert when the wave spring (e.g. resilient member) is either expanded or compressed. In one embodiment, moveable assembly 600 may have first friction area provided by a sequential series of socket assemblies 627 and a second friction area provided by a sequential series of friction limit sockets 625, which are not equipped with friction inserts, plungers, or wave springs. Instead, friction limit sockets 625 may be cast or machined out of a single material such as aluminum or stainless steel.

[0229] From an engineering point of view, the bottom third of moveable assembly experiences the highest stressing forces, and thus higher friction surfaces are needed to fix ball 626 in position, than are needed to fix ball 626A in position. In other embodiments, moveable assembly may be constructed using only friction limit sockets 625, or using only socket assemblies 627. Alternatively, one or more friction limit sockets 625 may be interspersed between two or more socket assemblies 627. In another embodiment, the concave interior contact surfaces of friction limit sockets 625 may be brazed with tungsten carbide to provide an improved friction surface.

[0230] Referring again to FIG. 6, an anti-torsion cable 639 may be provided to limit how much moveable assembly 600 may be twisted. Other components of moveable assembly 600 may include a base termination socket 637, a base termination ball 633, a tension cable ferrule 635, a strain relief 638 for the data cables, and ferrules 636 for the anti-torsion cable. In one embodiment, strain relief 638 is made of rubber or plastic.

[0234] FIG. 8 is an exploded perspective view of one embodiment of an actuator assembly 802. Actuator housing 807 may be made of any suitable durable material (e.g. metal, plastic, etc.) known in the manufacturing and computer arts. In one embodiment, housing 807 may be machined from a single block of aluminum or stainless steel, or cast from a liquid metal or liquid plastic injected or poured into a mold. It will be appreciated that the exterior and interior contours and protrusions or intrusions of housing 807 may be of any size, shape, or dimension necessary to fit a particular desired application.

[0236] Similarly, shafts 813, 814, and 816 may be formed of a metal such as stainless steel. The ends of shafts 813, 814, and 816 may be threaded to receive a nut, or equipped with an annular groove to receive a pressure fitted washer (e.g. retaining rings 817 and 821). Thrust washer 818 may be inserted within housing 807, at the blocked end, to provide a support surface for die spring 811. Spring shaft 806 may be coupled with die spring 811, and may be formed of a plastic or metal (e.g. stainless steel) using injection molding or machining processes well-known in the art.

[0239] Formed of a metal (e.g. stainless steel), tongue 805 is an oblong piece of metal, thick in its central portion and tapering to substantially flat ends. Each end may contain a circular orifice extending through its thickness. Similarly, a circular orifice may be bored through the tongue"s central portion from one side to the other. The edges of orifice may be recessed such that nylon washers 805A may be inserted into the orifice flush with the outer portions of tongue 805. Tongue 805 may be slidably inserted between the arms of crank 803 such that shaft 817 may be inserted through the orifices in housing 807, the crank arms, and the tongue"s central portion, to operatively couple tongue 805 with crank 803. A set screw 819 may be provided to adjust the tilt of tongue 805. Additionally, termination socket 824, equipped with insert 823, may be used to couple termination ball 822 with the proximal end of housing 807. In another embodiment, a flat base portion of display termination ball 822 that contains screw holes corresponding in number, dimension, and placement to the screw holes in the proximal end of housing 807 may be bolted directly to housing base 807.

[0263] FIG. 15A is a perspective view of one embodiment of a display termination socket 1524. In this one embodiment, socket 1524 is a hollow, annular ring. A first annular lip 1592 may be disposed within one end of socket 1524, and an annular lip 1591 may be disposed inside the socket 1524 near the other end. Socket 1524 is used to couple a display termination ball (not shown) with the actuator assembly previously described.

[0265] FIG. 16 is a side view of one embodiment of a tension cable 1634. Tension cable 1634 includes a ball ferrule 1654 on one end. The other end may be provided with a compression-fit ferrule (not shown) during assembly of the moveable assembly, as previously described. Additionally, a plastic or nylon sleeve 1656 is centrally disposed about cable 1634. In one embodiment, the distance 1651, measured from the center of ball ferrule 1654 to a first end of sleeve 1656, is approximately 398.90 mm. Approximately a 12.00 mm length 1655 of exposed cable 1634 may extend past the first end of nylon sleeve 1656. A distance 1653, measured from a second end of nylon sleeve 1656 to the center of ball ferrule 1654, is approximately 12.00 mm. In one embodiment, the diameter of ball ferrule 1654 may measure approximately 11.18 mm.

[0270] Referring to FIGS. 17A and 18A, in a further embodiment, annular friction rings 1892A and 1892B are coated with a high friction material such as tungsten-carbide to provide a high friction surface as previously described. Alternatively, annular friction rings 1892A and 1892B may be left uncoated. The annular friction rings not only contact concave surfaces 1792A and 1792B when moveable assembly 200 is tensioned, but also serve to limit the friction limit ball"s 1826 axis of rotation when moveable assembly 200 is relaxed. For example, friction limit ball 1826 may be tilted within socket 1725 until one of the friction limit rings contacts the inner lip of portion 1793A or 1793B. In embodiment, the axis of rotation is approximately in the range of approximately 10.0 to approximately 25.0 degrees. In other embodiments, the axis of rotation may be greater or lesser than the range illustratively given above.

[0273] FIG. 19A is a perspective view of one embodiment of an abrasive socket assembly 1927. A first plunger 1928A slidably fits around first friction insert 1930, which is coupled with a second friction insert 1931, which slidably fits within a second plunger 1928B. The plungers and friction inserts may be made of a metal (e.g. stainless steel or aluminum). Wave spring 1932 is disposed between the first and second plungers to space the plungers apart when moveable assembly 200 is relaxed. When thrust apart by wave spring (resilient member) 1932, plungers 1928A and 1928B lift friction limit balls 1826 out of contact with friction inserts 1930 and 1931, thus allowing friction limit balls 1826 to rotate freely within plungers 1928A and 1928B. In one embodiment, base portions of friction inserts 1930 and 1931 are threaded such that the friction inserts may be screwed together to assemble abrasive socket assembly 1927. Additionally, the concave inner surfaces of friction inserts 1930 and 1931 may be coated with an abrasive material such as tungsten carbide, aluminum oxide, or other abrasive material, as previously described, to provide a high friction support surface.

[0274] With reference back to FIG. 2A, in a further embodiment, abrasive socket assemblies 1927 are used in the bottom one-half to one-third portion of moveable assembly 200, while friction limit sockets 1725 are used in the upper one-half to two-thirds of moveable assembly 200. In this manner, moveable assembly 200 is equipped with at least two zones of friction: a high friction zone located near the base of moveable assembly 200, where the most torque occurs; and a low friction zone located towards the display end of moveable assembly 200. Alternatively, abrasive socket assemblies 1927 and friction limit sockets 1725 may be alternated throughout the length of moveable assembly 200.

[0277] FIG. 19D is a top view of first friction insert 1930, showing orifice 1991 bored through the base portion of first friction insert 1930 to allow passage therethough of data, torsion, tension, power, and other computer system-related cables.

[0282] FIG. 19I is a plan view of second friction insert 1931 showing an orifice 1994 bored through the base portion of the insert to allow for the passage therethrough of data, power, anti-torsion, tension, power, and other computer system-related cables.

[0289] It will be appreciated that aspects of the present invention may be used with a variety of moveable assemblies which allow for selectable positioning of a flat panel display device (FPDD). FIGS. 22A, 22B, and 22C show examples of such moveable assemblies which incorporate aspects of the present invention. Examples of these aspects include a base computer system which is moveable by a person and is not physically attached to a surface (except through the weight of the system due to gravity), or the use of a single actuator on the back of the FPDD in order to control the repositioning of the FPDD without requiring the actuation or loosening of multiple locks for the various joints, or a data cable which is housed within the structure of the moveable assembly.

[0290] FIG. 22A shows an example of a moveable assembly 2202 which is coupled to an FPDD 2203 at one end of the moveable assembly and is coupled to a base computer system 2201 at another end of the moveable assembly 2202. The base computer system 2201 is similar to the base computer system 242A. It includes many of the typical components of a computer system and has been designed in both size and weight to adequately and stably support the FPDD at a variety of different positions. For example, the base computer system 2201 is designed with sufficient weight such that, without physically attaching the base computer system 2201 (except through gravity) to the surface 2204, the base computer system 2201 will allow the FPDD 2203 to be extended out beyond the edge of the computer system 2201 as shown in FIG. 22A without causing the whole system to overturn. Thus the entire system 2200 allows the FPDD 2203 to be positioned at any one of a multitude of locations in which the FPDD 2203 can be positioned given the extent of reach provided by the moveable assembly 2202.

[0291] The moveable assembly 2202 includes a post (e.g. arm member) 2205, a post 2206, and a post 2207 which are coupled to each other through joints 2210 and 2209 as shown in FIG. 22A. The post 2205 is coupled to the base computer system 2201 through the rotatable joint 2208 which allows the post 2205 to rotate as shown by arrow 2216 around the joint 2208. The joint 2209 allows post 2206 to rotate relative to post 2205, allowing an angular displacement along the arrow 2214 as shown in FIG. 22A. Similarly, the angle between post 2206 and 2207 may be varied as these two posts are moved through the joint 2210, allowing motion along the arrow 2215. Both joints 2209 and 2210 include locking mechanisms 2212 and 2213 respectively, allowing the relative angular position between the corresponding posts to be fixed.

[0292] In the embodiment shown in FIG. 22A, articulation of both joints simultaneously will require loosening of both joints in order to allow complete control of the movement of the FPDD. In an alternative embodiment of the system shown in FIG. 22A, a single locking actuation control may be disposed on the surface of the FPDD 2203 in a manner which is similar to the handle 241 described above. In one embodiment, this single actuation control may be an electromagnetic control which loosens or tightens the joints electromagnetically under the control of the single actuation switch disposed on the FPDD 2203. The post 2207 terminates in a gimbal joint 2211 which is coupled to the FPDD to allow movement of the FPDD relative to the post 2207. Within the interior portions of the posts 2205, 2206 and 2207, there are disposed data and power cables 2220 and 2221. In one embodiment, these cables are concealed within the interior of the posts, which represent another form of a moveable assembly for supporting an FPDD. It will be appreciated that other computer system-related cables may be housed within the interior portions of posts 2205, 2206, and 2207.

[0293] FIG. 22B shows another example of a moveable assembly 2233 in a system 2233 which includes a base computer system 2232 and an FPDD 2248. The entire system 2233 rests, through gravity, on the surface 2239 without being physically attached to the surface except through gravity. As noted above, the bottom of the computer system 2232 may include a non-slip surface, such as rubber feet. Given that the weight and size of the base computer system 2232 is designed according to the teachings of the present invention to allow the support of the FPDD 2248 in a variety of selectable positions of the FPDD 2248, there is no need for the base computer system 2232 to be physically attached to the surface 2239 through the use of clamps or glues or bolts or screws, etc.

[0294] In one embodiment of the example shown in FIG. 22B, the computer system 2232 has a weight and size which allows a single human user to be able to move the computer system without assistance from another person or from a mechanical assistance. The base computer system 2232 is attached to post 2235 through a rotatable joint 2238, which allows the post 2235 to rotate around the base computer system along the arrow 2243. Post 2236 is coupled to post 2235 through the joint 2239, which will be locked through the locking mechanism 2240. The joint 2239 allows the angle between post 2235 and 2236 to be varied by moving the post 2236 along the arrow 2241. One end of the post 2236 supports a counterweight 2237 and another end of the post terminates in a gimbal joint 2244 which is attached to the back of the FPDD 2248. Posts 2235 and 2236, in the embodiment shown in FIG. 22B, include power and data cables 2270 and 2249, respectively, which are disposed within these posts and thereby concealed by these posts. A single actuating device or switch 2250 may optionally be located on the FPDD 2248 to allow for the release of one or more lockable joints in order to allow the selectable positioning or repositioning of the FPDD.

[0295] FIG. 22C shows another example of a moveable assembly 2264 in a system 2260 which includes the moveable assembly as well as an FPDD 2263 and a base computer system 2261 which rests on a surface 2262, which may be a desk surface. As noted above, the base computer system 2261 is typically designed to have a weight and size such that it will support the selectable positioning and repositioning of the FPDD 2263 over a large range of movement of the FPDD 2263. The moveable assembly 2264 includes three posts, 2267, 2268 and 2269, and also includes three joints 2271, 2272 and 2273, and also includes two counterweights 2277 and 2278. The moveable assembly 2264 also includes a gimbal joint 2274 which couples the post 2269 to the FPDD 2263. An optional single actuator control 2280 may be disposed on the FPDD 2263 in order to unlock or lock one or more of the joints. The embodiment shown in FIG. 22C may also optionally include the use of power and data cables, which are disposed within the posts 2267, 2268, and 2269.

[0296] In FIG. 23A, the computer controlled display system 2300 includes: a flat panel display device 2301 having a display surface 2302 and an input 2303 for receiving display data to be displayed on the display surface 2302. A moveable assembly 2304 is mechanically coupled to the flat panel display 2301. The moveable assembly 2304 has a cross-sectional area, which is substantially less than an area of the display surface 2302. Moveable assembly 2304 is moveable when handle 2307 is depressed, to allow the flat panel display device 2301 to be selectively positioned in space relative to a user of the computer controlled display system 2300. A base (e.g. moveable enclosure) 2305 is coupled mechanically to the moveable assembly 2304 and to the flat panel display device 2301 through the moveable assembly 2304. In one embodiment, the base houses concealed computer components, which include, but are not limited to: a microprocessor, a memory, a bus, an I/O (input/output) controller, optical drive, network interface, and I/O port. In such an embodiment, the microprocessor is coupled to the input of the flat panel display 2301. In a preferred embodiment, the cross-sectional area is defined by a cross-section taken perpendicularly to a longitudinal dimension of the moveable assembly 2304.

[0298] In a further embodiment, an actuator 2306 is attached to the flat panel display 2301 and coupled to a force generator (e.g. spring/piston assembly) which maintains the moveable assembly 2304 in a rigid mode when the actuator (handle) 2306 is in a first state, and which allows the moveable assembly 2304 to be moveable when the actuator (handle) 2306 is in a second state. In a preferred embodiment, the actuator 2306, through a single actuation, allows simultaneous positioning of the flat panel display 2301 and moveable assembly 2304 in multiple degrees of freedom.

[0299] In one embodiment, a data cable (not shown) is coupled to the input of the flat panel display 2301 at a first end, and coupled to a display controller (not shown) housed within the base 2305, the cable being disposed (and/or concealed) within the moveable assembly 2304. In a further embodiment, an anti-torsion cable (not shown) is coupled to (and preferably within) the moveable assembly 2304 to restrain the flat panel display (and the moveable assembly 2304) from being rotated beyond a pre-determined amount.

[0300] In a further embodiment, the longitudinal dimension of the moveable assembly 2304 extends from the flat panel display 2301 to the base 2305, and a weight of the system 2300 is less than about 25.0 lbs and a footprint size of the base 2305 is less than an area of about 500.0 square centimeters.

[0302] FIG. 23B is a perspective view of another embodiment of a computer controlled display device including a FPDD 2301 coupled with a moveable assembly 2304, which is coupled with a base 2305. As shown, actuator assembly 2306 is mounted on or contained within the rear housing 2308 of FPDD 2301. In one embodiment, the internal structure of FPDD is strengthened to withstand the compressive user forces applied simultaneously to handle 2306A and the front surface of FPDD 2301. The external shape of base 2305, in one embodiment, forms a toroid, as shown, and includes an inner metal Faraday cage, concealed by a layer of plastic, which repels external Electromagnetic Frequencies (EMF) that may interfere with operation of the computer components concealed within the base 2305. The Faraday cage also contains internal EMF generated by the concealed computer components. In one embodiment, the concealed metal Faraday cage, like the outer plastic layer, is manufactured in two pieces, a top portion and a bottom portion, which when fitted together form a toroid. The Faraday cage may be made of zinc, zinc alloys, or other suitable metals known in the art.

[0303] In one embodiment, the base 2305 and its internal components weighs approximately 13.0 pounds, while the FPDD 2301 weighs approximately 4.5 pounds. Additionally, the moveable assembly 2304, base 2305, and FPDD 2301 are manufactured such that a user can safely lift computer system 2300 using moveable assembly 2304 as a carrying handle. Additionally, the system is manufactured such that a user can safely hoist the entire system simply by grasping the FPDD 2301 and lifting. The terms “safely lift” and “safely hoist” mean that the various system components suffer minimal or no external or internal damage as a result of the user"s lifting actions.

[0304] As shown in FIG. 23B, the exterior plastic housing of base 2305 may be formed of two parts, a top portion and a bottom portion 2305A, which, when fitted together, form a toroid. The bottom portion 2305A may contain a plurality of peripheral ports and/or computer system-related controls 2310. Such ports and controls illustratively include, but are not limited to one or more of: a Firewire port, an Ethernet port, a modem jack, a power button, a reset button, a USB port, an infrared port, and similar computer system-related ports and controls.

[0305] FIG. 23C is a side view of the computer system 2300 shown in FIGS. 23A and 23B, according to one embodiment of the invention. System 2300 includes a FPDD 2301 having an actuator assembly 2306 attached thereto; a moveable assembly 2304 attached to the actuator assembly 2306, and a base 2305 attached to the moveable assembly 2304. In this embodiment, moveable assembly 2304 is a snake-like ball-and-socket assembly; however, it will be appreciated that other types of assemblies may also be used. Additionally, an optical drive (e.g. CD and/or DVD) aperture 2312 is provided in the top portion of base 2305. Aperture 2312, in one embodiment, includes an electronically activated fold-down door and an electronically activated slide-out optical disk tray. In one embodiment, pressing a button on a keyboard coupled with base 2305 activates the fold-down door and slide-out tray.

[0306] FIG. 23D is a rear-view of the computer system 2300 shown in FIGS. 23A-23C, according to one embodiment of the invention. As shown, system 2300 includes FPDD 2301, actuator assembly 2306, moveable assembly 2304, and base 2305, which includes a plurality of peripheral ports and computer system-related controls 2310, as described above.

[0307] FIG. 23E is a front view of the computer system 2300 of FIGS. 23A-23D, according to one embodiment of the invention, and showing FPDD 2301, viewing surface 2302, and base 2305.

[0308] FIG. 23F is another side view of the computer system 2300 of FIGS. 23A-23E, according to one embodiment of the invention, and showing FPDD 2301, actuator assembly 2306, moveable assembly 2304, and base 2305.

[0309] Referring now to FIG. 23G, a moveable assembly 2302 similar to that previously described with reference to FIGS. 4A and 4B is shown coupled with a flat panel display 2310, which, in one embodiment, includes a housing 2301 attached to a portion of the flat panel display obverse from a viewing portion 2311 of the flat panel display 2310. Housing 2301 is coupled to moveable assembly 2302 using at least one screw 2331 or a plurality of screws 2331. Within housing 2301 are various components of actuator assembly 2300A. Illustratively, such components include a tongue 2305, a crank 2303, a strut 2309, a spring guide 2308, and a spring 2370. Tongue 2305 has a distal end 2306B coupled with a ball ferrule 2335, which is attached to a tension cable 2334 extending through an interior portion of moveable assembly 2302. A proximal end 2306A of tongue 2305 is coupled with a distal end 2303B of crank 2303. The proximal end 2303A of crank 2303 is operatively coupled with the distal end of a strut 2309, and a proximal end of strut of 2309 is coupled with a distal end 2308B of spring guide 2308, which is inserted within the interior of a spring 2370. In one embodiment, spring guide 2308 progressively narrows or tapers downwards from the distal end 2308B to its proximal end 2308A, which includes a bushing 2350, which helps reduce friction and wear as proximal end 2308A slides within channel 2307. In one embodiment, tongue 2305 may include at its proximal end 2306A a channel extending therethrough into which a set screw or other screwlike mechanism 2305A is placed. Set screw 2305A may be adjusted to vary the angle at which the distal end of tongue 2305 contacts the ball ferrule of tension cable 2334.

[0312] Comparing FIGS. 4A and 23G, it will be appreciated that the angle at which tongue 2305 contacts ball ferrule 2335 is greater than the angle at which distal end of handle 460 contacts ball ferrule 434. In FIG. 23G, the changed tongue angle provides the tensioning mechanism (e.g. actuator assembly 2300A), with increased mechanical advantage as the cable 2334 becomes tighter, which reduces the amount of user force required to relax moveable assembly 2302. In one embodiment, an angle measured between a first horizontal line drawn through the center of pivot 2370 and a second oblique line extending from the center of pivot 2370, centrally through the distal end 2306B of tongue 2305, measures in the range of approximately 40.0 degrees to approximately 85.0 degrees, preferably approximately 70.0 degrees.

[0322] Glide ring 2500 may be made of various materials, including but not limited to: plastics, polymers, metals, glass, and fiberglass. Preferably, glide ring 2500 is made of Ryton®, having a nominal wall thickness of approximately 3.0 mm. In one embodiment, the material comprising glide ring 2500 may include an abrasive material or a lubricating material. For example, fiberglass strands may be incorporated within a glide ring formed of plastic, to increase the frictional qualities of glide ring 2500. Similarly, a lubricant such as (but not limited to) Teflon® may be incorporated within a glide ring formed of a polymer or a plastic. In one embodiment, a plurality of plastic glide rings 2500 may be manufactured, each having a different frictional quality. For example, Teflon®may be incorporated into a first glide ring positioned within a first socket assembly coupled with a flat panel display, while fiberglass may be incorporated within a second and third glide rings positioned within corresponding second and third socket assemblies operatively coupled with the first socket assembly. In one embodiment, glide rings 2500 are only used in the three socket assemblies nearest the flat panel display. In alternate embodiment, a plurality of glide rings 2500, having the same or different frictional qualities, may be used throughout the length of a moveable assembly.

[0329] Abrasive socket bearings 2600 may be comprised of various materials including, but not limited to: glass, metals, plastics, polymers, or fiberglass. In one preferred embodiment, abrasive socket bearing 2600 is comprised of Delrin® 500, AF, white; and has a nominal wall thickness of approximately 3.0 mm. In one embodiment, straight edges have a straightness tolerance of 0.05 per centimeter not to exceed 0.4 over the entire surface, and the flat surfaces have a flatness tolerance of 0.05 per centimeter, not to exceed 0.4 over the entire surface. The abrasive socket bearing 2600 may be added to a friction socket (not shown) to provide an improved and more stable friction performance than can be obtained using the friction inserts shown in FIGS. 19A-19C.

[0347] In one embodiment, a nylon sleeve 3203 may be fitted over tension cable 3202, and a Teflon® sheath 3204 may be fitted over the nylon sleeve 3203. Use of the nylon sleeve 3203 and the Teflon® sheath 3204 reduces sliding friction as tension cable 3202 passes through a moveable assembly (not shown). The reduced friction lessens the amount of work a user must provide on a state of the moveable assembly.

[0351] FIG. 33A is a perspective frontal view of a computer system 3300 including a flat panel display 3310 and a moveable base 3306 coupled with a moveable assembly 3302, according to another embodiment of the invention. In FIG. 33A, moveable assembly 3302 is coupled with a flat panel display 3310 to support the flat panel display 3310 at a designated space around the base 3306. In the embodiment shown, moveable base 3306 is hemispherical or toroidal in shape, and has a substantially flat, substantially circular, bottom portion 3306B from which a curved housing 3306A rises. The apex of housing 3306A is substantially centered at a pre-determined vertical distance above the center of the substantially circular bottom portion 3306B. In one embodiment, bottom portion 3306B is formed of a single piece of material and shaped so as to operatively couple with the hemispherical (or toroidal) top portion of housing 3306A. It will be appreciated that though the moveable base 3310 illustratively shown has a hemispherical shape, other designs, such as squarish shapes, rectangular shapes, cylindrical shapes, substantially pyramidal shapes, or other geometric shapes (together with modifications and/or combinations thereof) may be used. Thus, such designs, regardless of shape are to be construed as falling within the scope of the present invention.

[0352] The moveable base, together with the rest of the computer system 3300, weighs in the range of about 10.0 lbs to about 45.0 lbs, and is moveable by a single, unaided person. The moveable base is not required to be fixedly attached to the surface on which it rests. The size and weight of the moveable base is designed, in the manner described above, to allow the selective positioning of display 3310 at a wide variety of different positions without causing the system to overturn or flip over.

[0355] A plurality of holes 3304 may perforate the top of the hemispherical top portion of housing 3306A to allow airflow to flux in and out of the interior of base 3306 to cool electronic components housed within moveable base 3306. Such components may include, but are not limited to: a central processing unit, a memory, a display driver, and an optical drive (e.g. DVD and/or CD-rom drive).

[0357] Flat panel display device 3310, which may be of any type suitable for use with computer systems, includes a front viewing surface 3310. Its overall size and weight are chosen in coordination with the footprint and weight of the base 3306, such that base 3306 does not tilt when flat panel display 3310 is supported beyond the perimeter of base 3306 by moveable assembly 3302, which is attached to a rear surface of flat panel display 3310 and to a top portion 3306A of base 3306. The weight of base 3306 is chosen such that base 3306 adequately supports moveable assembly 3302 and flat panel display 3310 attached thereto without tipping; and such that a user can easily move computer system 3300. Thus, in one embodiment, the weight of base 3306 is in the illustrative range of approximately 10.0 to approximately 25.0 pounds.

[0358] FIG. 33B is perspective rear view of a computer system 3300 including a flat panel display device 3310 and a moveable base 3306 coupled with a moveable assembly 3302 according to one embodiment of the invention. In the embodiment shown in FIG. 33B, moveable assembly 3302 includes a tubular member 3326 having a distal end coupled with the rear portion 3310B of flat panel display 3310 and a proximal end coupled with the base 3306. The distal end of tubular member 3326 may include a flexible joint 3322A, secured to the distal end of tubular member 3326 by retaining assembly 3324A, which, in one embodiment, includes a tubular shaft and a retaining pin. Flexible joint 3322A may terminate in or be attached to a shaft 3320A, which is coupled to the rear portion 3310B through washer 3318A. The proximal end of tubular member 3326 may include a flexible joint 3322B, secured to the proximal end of tubular member 3326 by retaining assembly 3324B. Flexible joint 3322B may terminate in or be attached to a shaft 3320B, which is coupled to base 3306 through washer 3318B. Additionally, a gimbal (not shown) may be used to attach shafts 3320A and/or 3320B with flat panel display 3310 and/or base 3306, respectively. Retaining assembly 3324B secures flexible joint 3322A to tubular member 3326.

[0360] FIG. 33C is a side view of a computer system 3300 including a flat panel display 3310 and a moveable base 3306 coupled with a moveable assembly 3302 according to one embodiment of the invention. In FIG. 33C, computer system 3300 is viewed from the right hand side. Bottom portion 3306B of base 3306 may include a plurality of ventilation apertures 3326 used to cool the electronic components housed within the interior of base 3306.

[0361] FIG. 33D is a front view of a computer system 3300 including a flat panel display 3310 and a moveable base 3306 coupled with a moveable assembly (not shown) according to one embodiment of the invention. Flat panel display 3310 includes a viewing area 3310A. Base 3306 includes an aperture 3308, as previously described.

[0362] FIG. 33E is a rear view of a computer system 3300 including a flat panel display 3310 and a moveable base 3306 coupled with a moveable assembly 3302 according to one embodiment of the invention. Flat panel display 3310 includes a rear portion 3310B to which a distal end of moveable assembly 3302 is attached. As shown, a plurality of peripheral ports and system controls 3314, 3328, 3329, 3330, 3332, 3334, 3336, 3338, 3340, 3342, and 3344 may be included within base portion 3306B. Such ports and controls include but are not limited to: power button, microphone jack, speaker jack, Ethernet port, power plug, analog or digital telephone jack, infrared port, USB port, Firewire port, system reset button, and other computer system-related ports and controls.

[0363] FIG. 33F is another side view of a computer system 3300 including a flat panel display 3310 and moveable base 3306 coupled with a moveable assembly 3302 according to one embodiment of the invention. In FIG. 33F, computer system 3300 is viewed from the left hand side.

[0364] Referring now to FIG. 34, there is shown a simplified sectional side view of a computer system 3400 usable with an embodiment of the present invention. Computer system 3400 includes a base 3406 to which is attached one end of a moveable assembly 3401. The other end of moveable assembly 3401 is attached to a flat panel display device (FPDD) 3404. In the embodiment shown in FIG. 34, the moveable assembly 3401 is a mechanical linkage that supports the weight of FPDD 3404 as it is moved in one or more degrees of freedom relative to a weighted, moveable base 3406, which rests on a support surface such as a desk, table, or other substantially planar support surface. Alternatively, the end of moveable assembly 3401 attached to base 3406 (or the base 3406 itself) could be mounted on a wall or other support device.

[0365] It will be appreciated that the embodiments of the invention shown in FIGS. 34-39, and described below, use a novel four-bar linkage (e.g. closed loop mechanism), which generally includes three moving links, one fixed link, and four pin joints. For example, one embodiment of the invention includes a ground link (e.g. base biscuit) 3410B, an input link (e.g. canoes) 3401 (which correspond to canoes 3502A and 3502B in FIG. 35), an output link (e.g. compression rod) 3412, and a coupler link (e.g. display biscuit) 3410A. The uniqueness of the disclosed and claimed embodiments is that the packaging creates an illusion that an apparatus other than a four-bar linkage is used because the output link (e.g. compression rod) 3412 is hidden inside the structure of the input link (e.g. canoes) 3401.

[0366] It will be appreciated that a variety of relative motions of the coupler link (e.g. display biscuit) relative to the ground link (e.g. base biscuit) can be generated by varying the lengths of each of the lengths and the relative angles at which they attach to each other. Thus, the lengths of the input link (e.g. canoes) 3401 and output link (e.g. compression rod) 3412 may have the same or different lengths. Preferably, however, the lengths of the input link (e.g. canoes) 3401 and the output link (e.g. compression rod) 3412 are approximately the same. In such a configuration, the coupler link (e.g. display biscuit) 3410A maintains its orientation relative to the ground link (e.g. base biscuit) 3410B throughout the range of motion.

[0368] One of several unique features associated with the embodiment shown in FIG. 34, is that the counterbalancing spring 3408 and a moveable link (e.g. compression rod) 3412 of the four-bar mechanical linkage are housed within a cosmetic arm 3402 that acts as a fixed link. Cosmetic arm 3402 is formed of canoes 3502A and 3502B assembled together. The term “moveable link” means a link that moves relative to a fixed link. Unlike a fixed link, the angle(s) at which a moveable link attaches to a coupler link (e.g. display biscuit) 3410A and to a ground link (e.g. base biscuit) 3410B change as the four-bar linkage is raised and lowered. In the unique four-bar linkage shown in FIG. 34, canoes 3401 function as a fixed link when coupled to the center portions of display biscuit 3410A and ground biscuit 3410B. Thus, the angle at which canoes 3401 contact biscuits 3410A and 3410B remains substantially constant as the four-bar linkage is raised and lowered.

[0369] On the other hand, end 3412A of internal compression rod 3412 is attached to an off-center portion of ground biscuit 3410B. The other end of rod 3412 is attached at a corresponding off-center portion of display biscuit 3410A. When the four bar linkage is moved up and down, the lengths of compression rod 3412 and canoes 3401 do not change. However, the angle(s) at which compression rod 3412 attaches to biscuits 3410A and 3410B change relative to the angle(s) at which canoes 3401 attach to biscuits 3401A and 3410B. Thus, compression rod 3412 is said to “move” relative to canoes 3401. This movement occurs, in part, because compression rod 3412 is mounted to each biscuit a distance off center of the biscuit"s center, which creates a path length change.

[0371] Referring again to FIG. 34, it will be appreciated that the spring 3408 is not necessary to the operation of the four-bar linkage. Rather spring 3408 is provided, in one embodiment to counterbalance the weight of a flat panel display 3404 attached to display biscuit 3410A, such that the display feels substantially weightless to a user when the user grabs the display and attempts to move it. It will also be appreciated that the path length of spring 3408 changes as the four-bar linkage (e.g. moveable assembly) is moved up and down. For example, in one embodiment, spring 3408 expands as the four-bar linkage is raised, and contracts as the four-bar linkage is lowered. In its contracted state, spring 3408 stores potential energy. This stored energy is released to assist the user when spring 3408 expands during upward movement of display 3404.

[0372] Referring again to FIG. 34, cosmetic arm 3402 may also enclose and conceal a display data cable and a power cable for providing display data and power to the FPDD 3404. As shown in FIG. 35, base biscuit 3503 may include a channel 3507 through which the data and power cable may run.

[0374] In one embodiment, the physical specifications associated with computer system 3400 are as follows: Arm 3402 has a diameter of approximately 42.0 mm; rotational frictional elements (biscuits) 3410A and 3410B have centers spaced approximately 160.0 mm apart; and FPDD 3404 weighs approximately 4.94 lbs+/−10%. Regarding the range of motion provided in one embodiment, moveable assembly 3401 may yaw approximately +/−90.0 degrees from side to side; arm 3402 may pitch up and down approximately +/−90.0 degrees from the horizontal to the vertical; and FPDD 3404 may pitch approximately −5.0 degrees to approximately +30.0 degrees from vertical display orientation.

[0375] When manufacturing a computer system 3400 such as that shown in FIG. 34, it is desirable, but not necessary, that the system have one or more of the following characteristics. The display 3404 should be easily moved throughout the entire range of motion (when it is desired to move it). When the user has stopped moving the display, display 3404 should remain fixed at any point within the range of motion without noticeable sagging or backlash. During movement of display 3404, the motion of the moveable assembly 3402 should be smooth and silent (e.g. no “spronging” or other spring noises) and the friction feel should be constant, regardless of position or direction of motion. The moveable assembly 3402 should have no pinch points, and all cabling (e.g. display, data, and power cables) should be internal to the mechanism and not visible. Additionally, the moveable assembly 3402 should be designed for at least a 15,000 cycle lifetime without degradation of performance. The weight and size of the base 3406, arm 3402 and display 3404 should be light enough that one adult person, and even a child, can move the whole computer system (base, containing the majority of the electrical components of the computer system, arm and display) without any assistance and the base should be sufficiently heavy that it can support the whole computer system, with the display at a wide variety of locations, without requiring that the base be fixedly attached to the surface (e.g., a desk) on which it rests.

[0376] FIG. 35 is an exploded perspective view of one embodiment of the moveable assembly 3402 of FIG. 34. As shown in FIG. 35, component parts of moveable assembly 3402 include a first canoe 3502A designed to couple with a second canoe 3502B, and in so doing, to conceal various inner parts such as base rotation assembly 3503 and display mounting assembly 3505. A spring 3408 and a compression link 3412 may also be concealed within canoes 3502A and 3502B. Rod 3416 may be used to coupled spring core 3430 to canoes 3502A and 3502B.

[0377] FIG. 36 shows an exploded perspective view of one embodiment of a base biscuit assembly 3600 (which corresponds to base biscuit 3410B). Biscuit plate 3607 contains an adjustment mechanism and incorporates ratcheting features of that mechanism. Positioned behind the biscuit plate 3607, the counterbalance adjustment cam 3605 provides a way to change the effective moment arm of the counterbalance spring to allow for differences in display weight due to manufacturing tolerances. The operation of this cam is described in more detail in FIGS. 43A and 43B.

[0378] Friction element 3606, in one embodiment, is a conventional pivoting element that provides enough friction in