Abstract:
A data input keyboard apportioned between two demi-boards, the splay and pronation of which may be adjusted. Each of the demi-boards include a plurality of user activated keys extending therefrom, and define a distal side for orientation away from the user and a proximate side for orientation adjacent the user. The distal and proximate sides of the demi-boards are joined by inwardly facing sides and outwardly facing sides. A universal joint rotatably couples the inwardly facing sides of the demi-boards. Pivot point selectors are slidably mounted to the demi-boards for selecting pivot points along the outwardly facing sides, about which points the demi-boards are pivotably connected to the base member and are constrained for pivotal movement about the selected pivot points between a retracted position in which the demi-boards are co-planar and the inwardly facing sides are parallel and an extended position in which the demi-boards are splayed and pronated.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates generally to keyboards used for data entry and, more particularly, to such keyboards having adjustable splay and pronation. 
     The frequent use of keyboards for interfacing with computers and other devices can cause serious physical injury and pain to the wrists and other areas of the arms of users. This is generally caused by repetitive motion of the user&#39;s fingers on the keys of the keyboards. These disorders are commonly known as cumulative-trauma disorders or repetitive-motion injuries. As the number of individuals using keyboards on a continuous and repetitive basis has been increasing, these types of disorders have become more prevalent. Such repetitive use can also cause physical damage to the wrist, particularly to the carpal tunnel of the wrist. Such damage to the carpal tunnel, known as Carpal Tunnel Syndrome, can cause serious weakening of the hands and reduction in dexterity. 
     Tests indicate that a standard monoplane keyboard, i.e., a keyboard defined in but one plane and lying generally fiat on a table, exacerbates the problems associated with repetitive-motion injuries. The monoplane keyboard forces the user to rotate his or her forearms from a relaxed position to an extreme position so that the fingertips of each hand are horizontal. Furthermore, both wrists must be flexed away from the thumb side of the hand in order to line up the fingertips with the longitudinal rows of keyboard keys. It has been determined that repositioning the keyboard to permit a more &#34;natural&#34; or unflexed positioning of the forearms and hands significantly reduces the stress on the wrists and elbows, thereby reducing the instances of repetitive-motion injuries resulting from the use of keyboards. To this end, several keyboard designs have been developed. 
     For example, U.S. Pat. No. 4,509,873 issued to Ryan discloses a &#34;split&#34; keyboard in which keys are apportioned between two smaller boards, or &#34;demi-boards,&#34; which may be configured into an A-frame orientation to effect the pronation of the keyboard. The keyboard incorporates a base member having a distal face oriented away from the user and a proximate face oriented adjacent the user. Adjustment from a fiat horizontal position to an angled position is achieved by raising the central portion of the demi-boards from the fiat base member. The base member is angled so that the distal side is higher than the adjacent side. Additionally, the intersection point of the two demi-boards is perpendicular to the plane of the top face of the base member. 
     In another example, U.S. Pat. No. 4,597,681 to Hodges discloses an adjustable keyboard having a base member and a pair of demi-boards which may be raised at their joining edge into an A-frame configuration to adjust the pronation. Furthermore, each demi-board may be pivoted within its respective plane about an axis perpendicular to that plane to adjust the splay, in addition to the pronation, of the keyboard. Hodges provides a generally fiat base member with a generally dish-shaped surface of the keys. The keys may be positioned in a non-planar manner on each demi-board. 
     Each of these A-frame type of adjustable keyboards, while representing an improvement over the m,n,plane keyboard in terms of hand positioning, do not generally provide sufficient optimization of wrist and forearm positions when the fingers are placed in contact with the key faces. More particularly, these keyboards still force the user to bend the wrists upwardly and/or outwardly to align the fingertips with the keys on each demi-board. It is not possible, if one is to maintain proper finger alignment to the keys, to orient the wrists in linear alignment with the forearm, as the planes of the demi-boards in an A-frame orientation are still parallel to the proximal-distal axis of the keyboard base. In other words, the user is still forced into a position where his wrists are bent backwards to some degree forming an angle with the forearm, in order to properly contact such a keyboard. 
     As a consequence, keyboards have continued to evolve, with more recent designs utilizing adjustable demi-boards which may be raised, with respect to a base member, to a position wherein the distal edge of the demi-boards is oriented inwardly as compared to the adjacent edges of the demi-boards. As a result, when compared to the A-frame configurations, the demi-boards more closely parallel the forearms of the user so that the fingertips of the user may contact the keys on the demi-boards while maintaining improved linear alignment of the wrist and forearms. 
     As an example of a more recent keyboard design, U.S. Pat. No. 5,351,066 to Rucker et al. discloses an adjustable keyboard in which a pair of demi-boards are extendable from a retracted, flat position to an extended, tetrahedral position wherein the distal side of one of the demi-boards is closer to the other demi-board than the proximate side. While the Rucker keyboard provides for adjustment of both the splay and the pronation of the keyboard, it does so with only a single degree of freedom, i.e., the splay and pronation can not be independently adjusted. Moreover, Rucker does not provide for independent adjustment of the separate demi-boards either. 
     U.S. Pat. No. 5,228,791 to Fort cures some of the deficiencies of the Rucker invention in a keyboard arrangement in which a conventional keyboard is divided into two sections, each of which is separably supported on a joint which is freely rotatable and pivotable. The joint however is unwieldy and would not be feasible in a portable personal computer such as a &#34;notebook&#34; or &#34;laptop&#34; computer. 
     Therefore, what is needed is a keyboard in which the splay and the pronation thereof may be independently adjusted and which would be compatible with the space constraints of a relatively small portable computer. 
     SUMMARY OF THE INVENTION 
     The present invention, accordingly, provides a keyboard having demi-boards with adjustable pivot points formed along the outer edges thereof that overcome or reduce the disadvantages and limitations associated with prior keyboard designs. 
     In accordance with the present invention, a data input keyboard is apportioned between two demi-boards, the splay and pronation of which may be adjusted. Each of the demi-boards include a plurality of user activated keys extending therefrom, and define a distal side for orientation away from the user and a proximate side for orientation adjacent the user. The distal and proximate sides of the demi-boards are joined by inwardly facing sides and outwardly facing sides. A universal joint rotatably couples the inwardly facing sides of the demi-boards. Pivot point selectors are slidably mounted to the demi-boards for selecting pivot points along the outwardly facing sides, about which points the demi-boards are pivotably connected to the base member and are constrained for pivotal movement about the selected pivot points between a retracted position in which the demi-boards are co-planar and the inwardly facing sides are parallel and an extended position in which the demi-boards are splayed and pronated. A lift controller is interconnected between the base member and the universal joint for adjusting and controlling the height of the universal joint and the pronation of the demi-boards, which pronation becomes more pronounced, and splay less pronounced, as the pivot selectors are moved toward the proximate ends of the outer sides. 
     A technical advantage achieved with the present invention is that it allows the splay as well as the pronation of a keyboard to be adjusted into a large number of configurations, thereby aiding in the reduction of cumulative-trauma disorders and repetitive-motion injuries which commonly result from the repetitive motion of the hands and fingers on conventional keyboards. 
     Another technical advantage achieved with the present invention is that it is sufficiently compact to be implemented in a portable computer, such as a laptop or notebook computer. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a personal computer (PC) utilizing a keyboard according to a first embodiment of the present invention. 
     FIG. 2 is an cross-sectional view of the PC of FIG. 1 taken along the line 2--2 of FIG. 1. 
     FIG. 3 is a perspective view of a portion of the PC of FIG. 1 showing the keyboard in a splayed and pronated configuration. 
     FIG. 4 is an elevational view of a broken-away portion of the PC taken along the line 4--4 of FIG. 1. 
     FIGS. 5A and 5B are broken away perspective views of the PC of FIG. 1 taken along the line 5--5 of FIG. 3. 
     FIG. 6 is a partially exploded perspective view of an alternate embodiment of the PC of the present invention. 
     FIG. 7 is a plan view of an elongated lever utilized in the alternate embodiment of the PC of FIG. 6. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In FIG. 1 the reference numeral 10 refers to a portable personal computer (PC) embodying features of a first embodiment of the present invention. The PC 10 includes a base member 12, a graphical pointing device 14, a display screen 16 and, as viewed in FIG. 1, a keyboard assembly 20 comprising a left demi-board 22 and a right demi-board 24. As will be described below, the PC 10 also includes, as viewed in FIG. 1, left and right pivot point selectors 26 and 28, respectively, for selecting a pivot point about which the respective demi-boards 22 and 24 may be rotated to effect a splayed and/or pronated configuration to be described. A lift controller 30, having a body 30a, is provided for lifting the demi-boards 22 and 24 to facilitate pronation thereof as will also be described below. It is understood that a conventional ribbon cable (not shown) is also provided for electrically connecting the demi-boards 22 and 24 to the PC 10 as the splay and pronation thereof are adjusted. 
     It will be appreciated that, as viewed in FIG. 1, the demi-boards 22 and 24 are configured in a retracted, fiat position rendering them co-planer with the base member 12 and virtually identical to a standard computer data entry keyboard. Optimally, the shaping, position, and tactile pressure required for depression of a key is similar to that found in a standard keyboard so that adjustment to the keyboard assembly 20 is minimized and so that the user&#39;s tactile abilities in orienting himself or herself with respect to the keyboard assembly 20 are unchanged. This enables the user to use the keyboard assembly 20 in the retracted, or fiat, position in much the same manner as a &#34;standard&#34; keyboard, while having the option to also use the keyboard assembly 20 in the manner to be described. 
     The demi-boards 22 and 24 contain a plurality of user-activated keys laid out in a QWERTY arrangement, though it should be appreciated that other key arrangements may be employed with the keyboard assembly 20, such as the Dvorak or other key layouts. Each key is reserved, in accordance with established typing convention, for actuation by the user to generate a signal to display or type the symbol, letter, or number corresponding to the key depressed. 
     The left and right demi-boards 22 and 24 are split in an offset manner along a line 32 which passes between adjacent keys on the keyboard assembly 20 and which is offset along each key row in order to avoid splitting a key position. The line 32 also bisects a space bar into two halves. As further shown in FIG. 1, the left and fight demi-boards 22 and 24 define, respectively, left and fight proximate sides 22a and 24a intended for orientation adjacent the user, left and fight distal sides 22b and 24b intended for orientation away from the user, left and fight inner sides 22c and 24c facing each other, and left and fight outer sides 22d and 24d opposing each other. 
     With reference to FIG. 2, and in accordance with conventional keyboard design, the demi-boards 22 and 24 comprise, respectively, metal plate substrates 36 and 38, overlaid by electrically responsive plastic membranes 40 and 42, the thickness of which has been exaggerated for convenience of presentation. The membranes 40 and 42 are overlaid by monoblocks 44 and 46, which monoblocks have keys arranged thereon. 
     In accordance with the present invention, and as partially shown in FIG. 2, a socket 36a is formed at the inner distal corner of the metal plate 36 and a mating ball 38a is formed at the inner distal corner of the metal plate 38. The ball 38a and the socket 36a are coupled to form a conventional ball and socket universal joint 50, thereby pivotably connecting the left and fight demi-boards 22 and 24 together at the intersection of the distal sides 22b and 24b and the inner sides 22c and 24c of the respective metal plates 36 and 38. 
     The outer sides 22d and 24d of the respective metal plates 36 and 38 are hingedly attached to a left rail 52 and a fight rail 54, respectively, via two conventional piano hinge pins 56 and 58, respectively, which pass through appropriate hinge barrel portions of each corresponding member. For example, as more clearly shown in FIG. 3 with respect to the left rail 52, the piano hinge pin 56 passes through a plurality of barrel portions 52a of the rail 52 as well as corresponding barrel portions extending from the plate 36. It is understood that the outer sides 22d and 24d may be hingedly attached to the left and right rails 52 and 54, respectively, via a number of other types of hinges such as, for example, plastic &#34;living&#34; hinges or clutch hinges. Since the connection between the rail 54 and the plate 38 is identical to the foregoing, it will not be described in detail. 
     As further shown in FIG. 3, the rails 52 and 54 include horizontally extending flange portions 52b and 54b, and tab portions 52c and 54c, for reasons to be described. As shown in FIG. 4, the tab 52c includes a downwardly extending portion 52c&#39; and a horizontally extending portion 52c&#34;. A left array of holes 52d (one of which holes is shown in FIG. 2) and a right array of holes 54d (FIG. 3) are formed in the rails 52 and 54 between the respective ends thereof for reasons to be described. 
     With reference to FIG. 2, the pivot selector 26 is in the form of a hollow housing 26a having pivot pin 26b depending from the lower wall thereof. The selector housing 26a is sized to slidingly mate with the rail 52 and the flange portion 52b and, furthermore, to be vertically moveable so that, as assembled, the pin 26b can be removably inserted into any of the holes 52d. The right pivot selector 28, having a housing portion 28a and a pin 28b, is identical, in design as well as operation, to that of the left pivot selector 26 and will, therefore, not be described in detail. 
     As viewed in FIG. 2, the base member 12 includes left and right shelves 12a and 12b on which the respective rails 52 and 54 rest. The shelves 12a and 12b define arrays of holes 12c and 12d (FIG. 3) which align with corresponding respective holes 52d and 54d (FIG. 3) when the demi-boards 22 and 24 are in the retracted position shown in FIG. 1. With the pivot selector 26 mounted on the rail 52, the pivot pin 26b may extend downwardly through a selected hole 52d and through a corresponding base member hole 12c, thereby, pivotably connecting the left demi-board 22 to the base member 12. Similarly, with the pivot selector 28 mounted on the rail 54, the pivot pin 28b may extend downwardly through a selected hole 54d and through a corresponding base member hole 12d, thereby, pivotably connecting the fight demi-board 24 to the base member 12. 
     As shown in FIG. 3, a left arcuate track 12e and a fight arcuate track 12f, are formed in the respective shelves 12a and 12b for receiving the respective tabs 52c and 54c, thereby constraining movement of the rails 52 and 54 in a horizontal plane across the base member 12 when the demi-boards 22 and 24 are pivoted. It will be noted that the track 12e has opposing edges 12e&#39; and 12e&#34; shaped to follow arcs formed by the tab portion 52c&#39; as the rail 52 is pivoted respectively about a distal hole 12c&#39; or a proximate hole 12c (not shown). It is understood that the tab portion 52c&#34; is sized to extend sufficiently to engage the edge 12e&#34; as the rail 52 is pivoted about the distal hole 12c&#39;, and that the tab portion 54c&#34; is formed similarly. It is further understood that the track 12f includes edges 12f&#39; and 12f&#34; formed, with respect to arcuate movement of the tab portion 54c, similarly to the edges 12e&#39; and 12e&#34;. 
     With reference to FIG. 5A, a socket portion 38b is formed on the distal side of the ball portion 38a of the plate 38 for rotatably receiving a first ball portion 60a formed at one end of a lever arm 60. A second ball portion 60b is formed at the other end of the lever arm 60 and is received by a socket 30b formed on the body 30a of the controller 30, thereby linking the universal joint 50 to the controller 30. 
     As shown in both FIGS. 5A and 5B, the body 30a of the controller 30 also includes proximate and distal longitudinal slots 30c and 30d. As shown in FIG. 1, the base member 12 defines a slot 12g, formed in the base member 12 between the keyboard assembly 20 and the display 16, having a proximate straight edge 12g&#39; and a distal notched edge 12g&#34; for engaging the slots 30c and 30d, respectively, thereby slidingly securing the controller 30 within the slot 12g. A tooth 30e extends from the body 30a for engaging a selected notch in the notched edge 12g&#34;. The slots 30c and 30d are sufficiently recessed in the body 30a to permit the controller 30 to be moved toward the proximate edge 12g&#39; and longitudinally therealong, or to permit the controller 30 to be moved toward the distal edge 12g&#34; and the tooth 30e to engage a selected notch therein, thereby securing the controller 30 in the slot 12g. It is noted that, as shown in FIGS. 3 and 5A with the controller 30 so secured in the slot 12g, the lever arm 60 extends under a portion of the base 12. 
     In operation, the keyboard assembly 20 may assume a large number of configurations of varying splay and pronation, including a fully retracted, or fiat, configuration, as shown in FIG. 1, which would be similar to a standard monoplane keyboard. To adjust the splay and/or pronation, the pivot points about which the demi-boards 22 and 24 pivot must first be adjusted. With respect to the left demi-board 22, the pivot point may be adjusted by lifting the pivot selector 26 sufficiently to remove the pin 26b from the associated pivot hole 52d, sliding the selector 26 along the rail 52 to a desired pivot point, and then lowering the selector 26 to insert the pin 26b through the desired hole 52d as well as the corresponding base member hole 12c. The point about which the fight demi-board 24 pivots may be similarly adjusted. The user may then move the controller 30 toward the proximate edge 12g&#39; of the slot 12g, physically grasp the demi-boards 22 and 24 and pivot them about their respective pivot pins 26b and 28b, and secure the demi-boards 22 and 24 in place by moving the tooth 30e of the controller 30 into the appropriate notch 12g&#34;. 
     It can be appreciated that, in accordance with the present invention, as the demi-boards 22 and 24 are pivoted, the splay as well as the pronation of the keyboards may be variably effected depending on where the pivot points are located via the pivot point selectors 26 and 28. As the pivot point selectors 26 and 28 are positioned closer to the distal sides 22b and 24b of the demi-boards 22 and 24, the splay is more greatly effected than the pronation as the demi-boards 20 and 22 are pivoted away from the retracted position of FIG. 1. As the pivot point selectors 26 and 28, however, are moved closer to the proximate sides 22a and 24a of the demi-boards 22 and 24, the pronation is more greatly effected than the splay as the demi-boards 22 and 24 are pivoted away from the retracted position of FIG. 1. Alternatively, the pivot point selectors 26 and 28 may be adjusted independently to provide further flexibility to the configuration of the keyboard assembly 20. 
     FIGS. 6 and 7 show an alternate embodiment of the present invention. Since the alternate embodiment is similar to the first embodiment of FIGS. 1-5, identical components are given the same reference numerals. According to the embodiment of FIGS. 6 and 7, the socket 38b is oriented downwardly (as viewed in FIG. 6) and, as in the previous embodiment, the first ball portion 60a of the lever arm 60 is rotatably seated therein. The second ball portion 60b of the lever arm 60 is rotatably seated in a socket 62a formed at one end of an elongated lever 62 extending substantially horizontally between the keyboard assembly 20 and the base member 12. A ball portion 62b is formed at the end on the lever 62 opposite the socket 62a, and a longitudinal slot 62c is formed between the socket 62a and the ball 62b. The base member 12 includes a pivot pin 66 extending upwardly (as viewed in FIG. 6) through the slot 62c for constraining the lever 62 to pivotal movement about, and sliding movement along, the pin 66. The ball portion 62b is seated in a socket 64a of a controller 64 similar to the controller 30. The controller 64, having a tooth and longitudinal slots (not shown), is operative for sliding in a notched slot 12h, formed in the left side of the base member 12, in a manner similar to that of the controller 30 in the slot 12g. Accordingly, the controller 64 may be moved incrementally in the slot 12h and secured into a notch, as in the previous embodiment, thereby causing the lever 62 to pivot about the pin 66 and to move the arm 60. As a consequence, the universal joint 50 may be elevated up or down to effect pronation of the keyboard assembly 20 as in the previous embodiment. 
     The present invention, as described herein, has many advantages over the prior art. For example, it enables the splay as well as the pronation of a keyboard to be adjusted to assume a large number of configurations, thereby meeting the needs of any potential user and reducing cumulative-trauma disorders and repetitive-motion injuries which commonly result from the repetitive motion of the hands and fingers on conventional keyboards. Furthermore, the present invention is sufficiently compact to be implemented in a portable computer, such as a laptop or notebook computer. 
     It is understood that the present invention can take many forms and embodiments. The embodiments shown herein are intended to illustrate rather than to limit the invention, it being appreciated that variations may be made without departing from the spirit or the scope of the invention. For example, the keyboard assembly 20 may be adapted for use with a full-size desktop keyboard. The pivot selectors 26 and 28 may be ratchet mechanisms operable on slots formed in the rails 52 and 54 and the demi-board shelves 12a and 12b. The pivot selectors 26 and 28 may also be spring-loaded for urging the respective pins 26b and 28b downwardly into selected holes, or for biasing respective ratchets into selected slots. The lift controller 30 or 64 may also be spring-loaded to secure selected positions in respective slots 12g or 12h. The operation of the universal joints may be performed using other techniques and components, such as double-acting hinges. The universal joint formed by the coupling of the ball 62b to the socket 64a (FIG. 7) could be replaced by a simple hinged connection. The universal joint 50 may be lifted by other mechanisms such as a variation of the T-bar support member disclosed by Rucker et al. in U.S. Pat. No. 5,351,066. The demi-boards 22 and 24 may be reinforced in splayed and pronated configurations with additional structure. The lift controllers 30 and 64 may be secured in selected positions by other techniques such as knobs adapted for adjusting the friction between the controllers and the base member 12o 
     Although illustrative embodiments of the invention have been shown and described, a wide range of modification, change and substitution is intended in the foregoing disclosure and in some instances some features of the present invention may be employed without a corresponding use of the other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.