Abstract:
The invention relates to an adjustable keyboard to be used, for example, at a computer terminal ( 12 ). The preferred embodiment is in the form of a keyboard having a number of keys ( 5 ), the keyboard being formed in at least two segments ( 2, 3 ) which are mutually movable relative- to one another using a hinge or joint ( 6 ). Each of the segments ( 2, 3 ) of the keyboard has mounted thereon some of the keys ( 5 ). The relatively movable nature of the keyboard aims at reducing stress and discomfort to the user by eliminating contortion to the user&#39;s wrists. More particularly, discomfort to the user caused by pronation of the wrists and/or ulnar deviation of the wrists is reduced. The hinge or joint ( 6 ) may be in the form of a ball and socket-type joint with a locking mechanism, which preferably includes a pivoted handle ( 100 ), in the form of a lever, used for locking and unlocking the hinge or joint ( 6 ).

Description:
This application is a continuation-in-part of Application Ser. No. 09/384,700, filed Aug. 27, 1999, now U.S. Pat. No. 6,641,316. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The following invention relates to keyboards, and more particularly to a keyboard formed in two or more mutually pivotable segments which may be adjusted and locked into a number of different ergonomic positions. 
   2. Description of the Prior Art 
   Known keyboards of the type used at a computer terminal, for example, generally include a unitary board onto which alphanumeric keys are attached. It is a disadvantage of such known keyboards that the wrists and/or arms and shoulders of an operator must be contorted into a configuration which is stressful to the user after prolonged use of the keyboard. This problem is brought about by the fact that the hands of the user must be turned outwardly by pivoting of the wrists relative to the forearms, resulting in ulnar deviation. Discomfort to the user caused by pronation of the wrists is also a problem with these known keyboards. Pronated posture can also transmit stresses into the neck and shoulders of the user. 
   It is desirable to reduce pronation and ulnar deviation of the wrists in computer keyboards. To that end, U.S. Pat. Nos. 5,424,728 and 5,543,790 describe adjustable keyboards with at least two segments which are movable relative to one another via a hinge or joint. By moving the segments, the orientation of the user&#39;s wrists and hands can be adjusted to allow for reduction of ulnar deviation and pronation of the wrists. The hinge or joint in those patents is disclosed as preferably being a ball and socket-type joint. 
   U.S. Pat. Nos. Des. 362,434 and 5,454,652, assigned to Lexmark and U.S. Pat. No. 5,527,116, assigned to Maxi Switch, each show adjustable keyboards including a mechanism for locking the keyboard segments in place. However, in each of the keyboards described in those patents, the locking mechanism includes a large number of parts. As a result, those keyboards can be difficult to manufacture and assemble and therefore can be expensive, and those keyboards can be difficult for the user to adjust and lock. 
   SUMMARY OF THE INVENTION 
   It is the object of the present invention to overcome or substantially ameliorate the disadvantages of the prior art. It is therefore an object of the present invention to provide an adjustable keyboard which is inexpensive and simple to manufacture, is made of few parts and parts which are easy to manufacture and assemble, and which is easy for the user to adjust to a large number of positions. 
   There is disclosed a keyboard having a plurality of keys, the keyboard having at least two segments which are mutually movable relative to one another, and wherein each segment of the keyboard includes some of the keys. Typically, the keyboard has at least two mutually pivotable segments which are attached to one another at a top end of the keyboard segments by way of a hinge or joint, such that a front edge of the keyboard may spread apart in at least a substantially horizontal plane, to thereby reduce ulnar deviation in the keyboard user. Advantageously, the hinge or joint is adapted to allow pivoting in both horizontal and vertical planes such that the two segments of the keyboard may reside in different planes, so that the center of the keyboard is raised to reduce pronation and therefore decrease tension in the wrists and forearms of the user. 
   The hinge or joint may preferably be composed of a ball and socket joint which includes a locking mechanism. The locking mechanism may be fashioned using a pivoting handle, in the form of a lever, which includes a cam. The cam may be used to force bearing surfaces against a ball on a ball element, to thereby frictionally retain the ball and socket joint in a fixed position. Upon pivoting of the handle away from the keyboard, the cam may release the ball from the friction fit with the bearing surfaces, thereby allowing the ball to slide in the socket, and therefore allowing the keyboard segments to be adjusted relative to one another. 
   A support may be provided generally below the ball and socket joint so as to maintain the central region of the keyboard at a raised preselected level, if needed. 
   Beneficially, a number pad region of the keyboard can be provided which is pivotable relative to one of the segments such that the number pad region may reside in a plane other than the plane of the segment to which the number pad is hinged. 
   Typically, the keyboard is divided into segments which coincide with generally accepted keyboard areas used by a particular hand. 
   The present invention provides a keyboard in which the wrists of the operator need not be contorted as they would be in use of a conventional keyboard. 
   In order to electrically connect the keys of one segment of the keyboard to the other, a cable or any suitable contact may be provided between the two segments. Additionally, an infrared or other electromagnetic signal may be used to transmit signals from the keyboard to the computing device without the need for a cable or other physical connection. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings, wherein: 
       FIG. 1  is a schematic plan view of a keyboard of the present invention; 
       FIG. 2  is a schematic elevational view of the keyboard of  FIG. 1 ; 
       FIG. 3  is an exploded perspective view of the components of an embodiment of the hinge or joint and locking mechanism of the present invention; 
       FIG. 3   a  is a cross-sectional view, through line IIIA—IIIA, of the cam of the embodiment of  FIG. 3 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention relates to a keyboard  1  to be used, for example, at a computer terminal  12 . In the accompanying drawings there is schematically depicted a keyboard generally indicated by reference numeral  1 . Keyboard  1  includes separate segments  2 ,  3 , and  4 , each having a plurality of keys  5 . It is to be understood that the configuration of the keys on segments  2 ,  3 , and  4 , may be in any suitable form which allows access to the appropriate hand corresponding to segments  2 ,  3 , and  4 , and need not be the configuration shown in  FIG. 1 . 
   Segments  2  and  3  of keyboard  1  are usually attached by a hinge or joint  6 , which may provide on e or more degrees of freedom of relative movement between segments  2  and  3 . Hinge or joint  6  in the preferred embodiments is described in more detail below. As described in more detail below, a handle  100 , in the form of a lever, forms a portion of a keyboard locking mechanism. The handle  100  may be pivoted from a locked position, which fixes the position of the hinge or joint  6 , to an unlocked position  101 ′ (dashed lines), which allows pivoting movement of the segments  2 ,  3  relative to one another in one or more planes. The segment  2  or  3  containing the handle  100  may include an indentation  110  near the end of the handle  100  to allow easier access to, and pivoting of, the handle  100  by the user. 
   Segment  4  of keyboard  1 , if provided, has mounted thereon numerical keys  5  and is attached to segment  3  by hinge or joint  7 . Hinge or joint  7  may extend along line  8  illustrated in  FIG. 1  so as to provide at least one degree of relative movement between segments  3  and  4 . Alternatively, a hinge or joint of the type described below may be employed between segments  2  and  3  and may be located at either an upper or lower end of line  8  in  FIG. 1 . Segment  4  is an optional segment, and the keyboard  1  may be formed of only segments  2  and  3 . 
   It should be appreciated that segments  2  and  3  of keyboard  1  may pivot with respect to one another while each remaining in a single plane (i.e., the plane of  FIG. 1 ), or in multiple planes (i.e., the planes of  FIGS. 1 and 2 ). Movement of the segments  2 ,  3  in the plane of  FIG. 1  acts to prevent or reduce ulnar deviation of the user&#39;s hands and wrists, while movement of the segments  2 ,  3  in the plane of  FIG. 2  acts to prevent or reduce pronation of the user&#39;s wrists. As depicted in  FIG. 2 , a center region of keyboard  1  is raised above the level of a desk  14  on which the keyboard  1  is supported. An optional support (not shown) may be provided generally below the hinge or joint  6  so as to maintain the central region of the keyboard  1  at a raised preselected level, if needed. 
   Should an operator of the keyboard  1  not be comfortable with a hinged-apart orientation of the keyboard  1 , the keyboard  1  may simply be returned to a conventional configuration. 
   In order to electrically connect the keys of one segment (e.g. segment  2 ) to the other (e.g. segment  3 ), a cable  10  or any suitable contact may be provided between the two segments. Additionally, an infrared or other electromagnetic signal may be used to transmit signals from the keyboard to the computing device without the need for a cable or other physical connection. 
     FIG. 3  shows an exploded view of the components of a first embodiment of a locking mechanism and hinge or joint of the present invention. A handle  100 , in the form of a lever, includes a handle section  101  at one end and a cam  102  at another end. Cam  102  includes a cam surface  103 . On either side of cam  102  are flanges  104 , each of which includes a hole  105 . A cam hole  107  passes through cam  102  and is aligned with holes  105 . Handle  100  is preferably made of an inexpensive, but relatively rigid, material such as an engineering plastic such as polyketon, sold under the trade name CARILON. 
   A retaining pin  200  passes through holes  105  and the cam hole  107 , to retain handle  100  on socket element  700 . Pin  200  is preferably manufactured of an inexpensive and somewhat resilient material, such as an engineering plastic, for example a glass-filled polyamide or nylon, sold under the trade name GRIVORY GV-5H, and has at least one end which is slightly enlarged, so as to allow a press or interference fit between the pin  200  and holes  105 , to thereby hold handle  100  and socket element  700  together. Flanges  701  on socket element  700  fit slidingly within slots  106  between flanges  104  and cam  102 , such that pin  200  fits through holes  105 , holes  702  on flanges  701 , and the cam hole  107 , thereby allowing pivoting of handle  100  relative to socket element  700  about the axis of pin  200 . 
   A camming pin  300  is retained adjacent to the cam  102 . Camming pin  300  includes a camming surface  301  and a pin  302  projecting away from camming surface  301 . Pin  302  fits through holes  401  and  501  in biasing element  400  and bearing element  500 , respectively, such that bearing element  500 , biasing element  400  and camming pin  300  are connected and aligned together. Camming pin  300  is preferably made of an inexpensive, but relatively rigid, material such as an acetal co-polymer or nylon, sold under the trade name DURACON-90. 
   A biasing element  400  is retained adjacent to the locking pin  300 . The biasing element is preferably disc-shaped, and includes a hole  401  passing through its center. Biasing element  400  is preferably made of a relatively resilient material, such as a urethane rubber, or could be made of a spring steel component, so that it acts as a spring to provide a bias against the action of cam  102  during locking and unlocking. The biasing element  400  serves to reduce the need for exacting tolerances in the locking mechanism of the present invention. The biasing element  400  also serves as a clutching mechanism so that if too much pressure is exerted on the keyboard segments  2 ,  3 , the provision of the biasing element  400  allows for slippage between the ball element  600  and socket element  700  described below. 
   A bearing element  500  is retained adjacent to the biasing element  400 . On the end of bearing element  500  adjacent to the biasing element  400 , the bearing element  500  includes a hole  501 , through which the end of pin  302  passes. The opposite end of bearing element  500  includes a bearing surface  502  which is preferably hemispherical in shape. The bearing element  500  is mounted within socket element  700  for sliding movement relative to both the keyboard segments  2 ,  3 . The bearing element  500  is preferably made of a relatively inexpensive and rigid material, such as an acetal copolymer, sold under the trade name DURACON M-90. 
   A ball element  600  is mounted adjacent to the bearing element  500 . A ball  601  on ball element  600  fits within, and is slidably mounted against, bearing surface  502 . A shaft  602  connects ball  601  to a retaining portion  603  of ball element  600 . Retaining portion  603  may include one or more holes  604 , which are used to affix ball element  600  to one of the keyboard segments  2 ,  3  or  4 , via suitable attachment mechanisms such as screws or bolts. The ball element  600 , although shown as spherical in the drawings, could alternatively be hemispherical in shape. The ball element  600  is preferably made of a relatively inexpensive and rigid material, such as a glass or mineral filled acetal copolymer, or alternatively could be fabricated of stainless steel. In an alternative embodiment of the invention, the cam surface  103  may provide direct contact with the ball element  600 , thereby eliminating the need for the bearing element  500  and biasing element  400 . 
   Ball  601  fits within a socket element  700 , such that the shaft  602  and retaining portion  603  project out of an opening  706  in socket element  700 . An interior bearing surface of socket element  700 , at socket end  705 , is hemispherical in shape. Ball  601  on ball element  600  fits within, and is slidably mounted against, the bearing surface within socket end  705 . Socket element  700  includes flanges  701 , which are spaced and shaped so as to slidably fit within slots  106  on handle  100 . Holes  702  on flanges  701  are spaced to align with holes  105  on handle  100 , and the cam hole on handle  100 , so that the pin  200  can fit through those holes, allowing the handle  100  to be pivoted relative to socket element  700 . Socket element  700  may also include a flange  703  with one or more holes  704 , which are used to affix socket element  700  to one of the keyboard segments  2 ,  3  or  4 —adjacent the segment  2 ,  3  or  4  to which ball element  600  is affixed—via suitable attachment mechanisms such as screws or bolts. The socket element  700  is preferably made of a relatively inexpensive and rigid material, such as a glass or mineral filled acetal copolymer, or alternatively could be fabricated of metal. 
   Operation and manipulation of the keyboard  1  of the present invention will now be described. When it is desired to set a new position of the keyboard  1  segments  2  and  3  relative to one another, the handle  100  is pivoted to its unlocked position  101 ′. Pivoting of the handle  100  is accomplished by rotating handle  100  about pin  200 , thereby moving cam  102  relative to camming surface  301 . In the unlocked position low  101 ′, the cam surface  103  is spaced a shorter distance d 1 , from the axis of pin  200  that the distance d 2  of cam surface  103  from the axis of pin  200  in the locked position. As a result, in the locked position, the cam  102  pushes the camming pin  300  in the direction of the ball element  600 , and in the unlocked position low  101 ′ the cam  102  allows camming pin  300  a degree of movement away from ball element  600 , under the influence of biasing element  400 . 
   In the unlocked position  101 ′ the bias of biasing element  400  allows camming pin  300  to move in the direction away from ball element  600 . This movement also allows movement of the bearing element  500  away from the ball element  600 . As a result, the ball  601  is unclamped between the bearing surface  502  and the bearing surface inside the socket end  705 , allowing the ball  601  to rotate between those surfaces. Rotation of the ball  601  is effected by pivoting movement, in one or more places, of the segments  2 ,  3  relative to one another, one of the segments  2 ,  3  being affixed to the retaining portion  603  projecting out of opening  706  in socket element  700 , and the other segment  2 ,  3  being affixed to socket element  700 . 
   When the segments are unlocked by moving handle  100  to unlock position  101 ′, the segments  2 ,  3  may be pivoted in a horizontal plane (i.e., the plane of  FIG. 1 ) relative to one another to reduce or eliminate ulnar deviation in the user&#39;s hands and wrists. The segments  2 ,  3  may also be pivoted in a vertical plane (i.e., the plane of  FIG. 2 ) relative to one another to reduce or eliminate pronation in the user&#39;s wrists. 
   After a desired orientation of the segments  2 ,  3  relative to one another is achieved, the handle  100  is pivoted around pin  200  to its locked position, thereby moving cam  102  relative to camming surface  301 . In the locked position, the cam surface  103  is spaced a longer distance d 2  from the axis of pin  200  than the distance d 1  of cam surface  103  from the axis of pin  200  in the unlocked position. As a result, in the locked position, the cam  102  pushes the camming pin  300  in the direction of the ball element  600 . In the locked position, the camming pin  300  moves in the direction toward ball element  600 . This movement pushes the biasing element  400 , and thus the bearing element  500 , toward the ball element  600 . As a result, the ball  601  is clamped between the bearing surface  502  and the bearing surface inside the socket end  705 , fixing the ball  601  against rotation between those surfaces as the result of frictional forces. The segments  2 ,  3  are thus fixed in position relative to one another, as a result of the clamping of ball  601  between the bearing surface  502  and the bearing surface inside the socket end  705 , as well as fixing of one of the segments  2 ,  3  to the retaining portion  603  and the other segment  2 ,  3  to socket element  700 . 
   While the forgoing represents a description of preferred embodiments of the invention, it is to be understood that the claims below recite the features of the present invention, and that other embodiments, not specifically described hereinabove, fall within the scope of the present invention.