Abstract:
Various embodiments of the present invention comprise a signal generator for sending an electrical signal from an expandable, flexible layer of material, the signal generator comprising an upper layer of flexible, resilient material and a lower layer of flexible, resilient material which between them define a cavity for enclosing an expandable material such as a cellular foam or gas, whereupon localized distortion of one of the layers of flexible material, effects a signal generation within the structure, which is transmissible through a proper circuit to an outside electrical device. A circuit may be arranged adjacent a plurality of said keys which senses when several of said keys are depressed in a skewed or sideways manner, so as to effect movement of a cursor or pointer on a monitor in communication with a processing unit and said keyboard.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 11/005,168, filed Dec. 6, 2004, which is a continuation of U.S. patent application Ser. No. 10/011,241, filed Nov. 5, 2001, now abandoned, which was a divisional of U.S. patent application Ser. No. 09/549,080, filed Apr. 15, 2000, now U.S. Pat. No. 6,313,762, which is a continuation of U.S. patent application Ser. No. 08/974,356, filed Nov. 19, 1997, now U.S. Pat. No. 6,052,071, which is a divisional of U.S. patent application Ser. No. 08/564,631, filed Nov. 29, 1995, now U.S. Pat. No. 5,691,716, which is a continuation-in-part of U.S. patent application Ser. No. 08/447,116, filed Aug. 18, 1995, now U.S. Pat. No. 5,666,112, which is a continuation of U.S. patent application Ser. No. 08/098,851, filed Jul. 29, 1993, now U.S. Pat. No. 5,459,461. The aforementioned applications and patents are all hereby incorporated by reference in their entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    This invention relates to keyboards, and more particularly, to signal generating devices which have keys adapted for moving a cursor by themselves in addition to permitting other data input. 
       BACKGROUND OF THE INVENTION 
       [0003]    Miniaturization of electronic devices such as calculators, computers, telephones, amusement devices, and light electronic equipment has advanced rapidly over the past few years. Data entry devices have become miniaturized as well. The term “chicklet keys” has been used to identify very small tabs or keys utilized on some small devices for data entry into that device. While their keypads are somewhat “storable”, the problem with that type of terminal is that the operator has a difficult time in hitting the proper key to efficiently do the job. The data entry operators hands/fingers are relatively large, and these keys lack the full stroke, size and tactile contact feedback of full sized keyboards that are preferred. Current laptop and palmtop devices suffer from the problem of short stroke and compacted dense key layout. Further difficulties arise when cursor movement is desired. Touch pad screens are data entry devices which have replaced the “mouse” or trackball. Accuracy, however, may be lacking with such data entry devices, inasmuch as the exact location of a particular cursor/data entry point may be difficult to discern. One patent which has tried to show an improvement in the cursor moving art is U.S. Pat. No. 5,278,557 to Stokes et al. This patent, however, discloses only a single key which is dedicated exclusively to the movement of a cursor. This is similar to a joy stick “built-into” the keyboard. This does not facilitate cursor movement while the operator&#39;s hands are on the alpha/numeric keys themselves. 
       BRIEF SUMMARY OF THE INVENTION 
       [0004]    Aspects of the present invention comprise a signal generator arrangement for sending an electrical signal from an input stroke, the signal generator being defined by an upper layer of flexible, resilient, plastic-like material having an inner surface into which a fluid component is pressed thereagainst, and a signal completion means arranged within the fluid component, so as to establish an electrical signal to be sent in a proper circuit when the upper layer of flexible, resilient plastic material is deformed, or pressed by the input stroke. The fluid component adjacent the upper layer of flexible, resilient plastic material may be an expandable open or closed cellular foam material. The foam material may include a conductivity additive therewithin, which conductivity within the foam increases as the foam is compressed beyond a lower limit so as to establish a signal from that vicinity of the flexible, resilient plastic material of the upper layer. 
         [0005]    A lower layer of flexible material may be disposed adjacent to the upper layer of flexible material, so as to define a resilient cavity or foam filled chamber therebetween. The upper layer of flexible plastic material may have a plurality of molded structures formed thereon, the molded structures enclosing at least a portion of the fluid or foam filled component thereby. An arrangement of electrodes may be arranged on or adjacent the inner side of the upper layer of flexible material, the electrodes being in electrical communication with a proper circuit through at least one of the layers of flexible material, and in communication with a further electrical device. 
         [0006]    The cavity defined by the upper and lower layers of flexible, resilient plastic material may be filled with a gas through a valve arranged between one of the layers. The signal completion arrangement may include an arrangement of strain gauges arranged adjacent the inner surface of the upper resilient, flexible layer of material. 
         [0007]    One aspect of the invention thus comprises a signal generator for sending an electrical signal from an input stroke, comprising an upper layer of flexible, resilient plastic material having an inner surface, a fluid component pressing against the inner surface, and signal completion means arranged within the component pressing against the inner surface of the upper layer, so as to establish an electrical signal to be sent to an electrical device from the signal generator upon the receipt of a force input stroke thereon. The fluid component may in one embodiment, comprise an expandable cellular foam. The signal completion means may comprise a conductivity additive in the cellular foam. The signal generator may include a lower layer of flexible material having a periphery attached to the periphery of the upper layer, to define a fillable cavity therebetween. The upper layer has a plurality of molded structures molded therewith, the molded structures enclosing the fluid component means, and an arrangement of electrodes arranged adjacent the inner side of said upper layer, the electrodes being in electrical communication with a circuit through at least one of the layers of flexible material. A fluid controlling valve is arranged through at least one of the layers of flexible material, to permit entry of gas to the fillable cavity between the upper and lower layers of flexible material. The signal completion means in one embodiment, may comprise a strain gauge arranged adjacent the inner surface of the upper layer. The signal completion means also may comprise a plurality of layers of cellular foam, each layer having a different physical characteristic therewithin. The signal completion means may also comprise a plurality of spot electrodes arranged adjacent the inner surface of the upper layer, so as to establish a complete circuit during localized distortion of the upper layer. 
         [0008]    Another aspect of the invention comprises a signal generator for sending information to a computer monitor to effect proportional directional movement of a pointer or cursor on that monitor, comprising a plurality of the regular alpha-numeric depressible keys on the signal generator for the sending of electrical signals to the monitor through an electrical circuit, and a further electrical circuit arranged between each of said plurality of depressible keys and the signal generator, to effect motion in a cursor on the monitor, when the plurality of keys are depressed somewhat sideways or skewedly. The further electrical circuit in one embodiment, comprises a multiplicity of electrical components spaced adjacent the periphery of each of the plurality of depressible keys, each of the spaced components connected in parallel to correspondingly positioned components spaced about the other of the depressible keys, and connected to a processing unit for input to said monitor. The electrical components may comprise resistors which are variable in nature such as potentiometers, strain gages, or conductors in communication with the compressible foam (variable conductivity depending on the amount of conductors therein, and the amount of compression applied thereto), comprising part of a secondary contact point to receive signals when any of the keys are depressed or moved in a skewed or sideways direction. The signal generator may have an upper surface comprised of a layer of flexible plastic material, and the plurality of depressible keys may also formed of that flexible plastic material. A plurality of primary contact points are disposed on the lower surface of the layer of flexible material juxtaposed with respect to the secondary contact points to permit electrical communication therebetween when any of the plurality of keys are moved in a skewed manner, or pressed with an increased force to create a greater conductivity to get such cursor to move faster. 
         [0009]    Another aspect of the invention comprises a method of generating an electrical signal in order to effect proportional movement of a cursor on a computer monitor, comprising the steps of arranging a plurality of movable (depressible) keys on a keyboard so that when any of the keys (preferably standard alpha/numeric keys) are moved, an electrical signal is sent through a first electrical circuit to a processing unit and to a monitor for display of that signal thereon, and arranging a further electrical circuit in a spaced relationship with respect to the keys, so as to send a further electrical signal to the monitor to move a cursor in a particular direction when a plurality of the keys are moved with a sideways component of motion (skewed manner). The method of generating an electrical signal includes pressing simultaneously, more than one of the plurality of depressible keys in a common skewed direction, to effect movement of the cursor or pointer on the monitor in a corresponding direction. The method of generating an electrical signal also comprises the step of increasing the force/speed of the skewed moving or increasing the number of keys simultaneously pressed in a skewed manner, to effect an increase in the speed of movement of the cursor or pointer. 
         [0010]    Still another aspect of the invention includes a method of generating an electrical signal from a keyboard in order to effect movement of a cursor on a monitor, comprising the steps of: moving sideways a plurality of keys arranged on the keyboard so as to send a signal from a sideways motion sensor arranged with respect to each of the plurality of keys, to the monitor, to induce cursor motion in the monitor; arranging as the sideway motion sensors, a plurality of resistors about each of the plurality of keys; connecting in parallel, corresponding resistors from each of the plurality of keys, the parallel resistors arranged as a circuit connected to the processing unit, so as to establish a circuit for sending a proportionally increasing signal to the monitor, when an increasing number of keys are moved in a corresponding sideways direction. The method includes the step of arranging as the sideways motion sensors, a plurality of strain gages between the plurality of keys and the keyboard, the strain gages connected to the monitor through a processing unit, so as to establish a circuit for sending a proportional changing signal to the monitor depending on the quantity of keys moved sideways, to effect movement of the cursor or pointer. The method also includes the steps of: fabricating the upper surface of the keyboard from a layer of flexible plastic sheet material; molding the keys into a digit depressible form as a unitary component of the flexible plastic sheet material; arranging a lower layer of material as a base of the keyboard which is sealed at a common periphery with the layer of flexible plastic material comprising the upper layer; injecting a charge of compressible foam into a cavity defined between the upper layer of flexible plastic sheet material and the lower layer of material; placing a dispersion of electrically conductive particles within the foam, so as to permit portions of the foam to be electrically conductive when the particles are compacted against one another, increasing their conductivity to establish a completed circuit therein as the foam is compressed; and arranging a plurality of contacts adjacent the periphery of the lower surface of each of the plurality of keys, the contacts being part of a circuit connected to a processing unit to effect movement in a cursor or pointer on the monitor when a key is pressed sideways. The method includes the steps of: pressing downwardly towards the base of the keyboard at least one of the plurality of keys so as to send an electrical signal to the processing unit to generate an alpha/numeric response on the monitor; and moving sideways with respect to the base of the keyboard at least two of the plurality of keys so as to send an electrical signal to the processing unit to effect a corresponding movement in a cursor or pointer on the monitor; and decompressing the foam so as to separate any compacted conductive particles, to open any circuit established therein, to await further compression and establishment of another circuit therein for transmission of a signal to the processing unit and monitor. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The objects and advantages of the various embodiments of the present invention will become more apparent when viewed in conjunction with the following drawings, in which: 
           [0012]      FIG. 1  is a cross-sectional view of a signal generator with a foam arranged therewithin; 
           [0013]      FIG. 2  is a side-elevational view of a flexible keyboard assembly arranged on a force pad; 
           [0014]      FIG. 2   a  is a flexible keyboard according to one embodiment of the present invention shown in a rolled up configuration; 
           [0015]      FIG. 2   b  is a side-elevational view of the flexible keyboard shown in  FIG. 2   a , in an unrolled or generally planar configuration; 
           [0016]      FIG. 2   c  is a side-elevational view of the flexible keyboard shown in  FIG. 2   b , in an expanding state; 
           [0017]      FIG. 2   d  is a side-elevational view of the flexible keypad shown in  FIG. 2   c , wherein the keypad is fully expanded; 
           [0018]      FIG. 3  is a cross-sectional view of a portion of a flexible key shown with conductive means arranged on its upper material; 
           [0019]      FIG. 4  is a cross-sectional view of a key of flexible keyboard, having signal establishing conductive means on the upper flexible layer and within the enclosed material as well; 
           [0020]      FIG. 4   a  is a cross-sectional view of a key for a flexible keypad, showing conductive means arranged within material disposed within the key; 
           [0021]      FIG. 4   b  is a cross-sectional view of a key on a flexible keypad having multiple density materials disposed within the molded key; 
           [0022]      FIG. 5  is a cross-sectional view of a key on a keyboard showing a signal generating means arranged on the side walls of the molded key portion; and 
           [0023]      FIG. 6  is a schematic and cross-sectional representation of a portion of a keyboard showing a cursor movement arrangement according to one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0024]    One embodiment of the present invention relates to an expandable signal generator apparatus  58 , as shown in a partial side-elevational view, in  FIG. 1 , wherein an expandable key  60  has a pre-molded upper layer  62  in a desired key configuration, having an enclosed volume of open or closed cell foam  64 . The upper layer  62  of the key  60 , being made from a thin layer of plastic material which flexes when pressed by an outside force. The foam  64  is yieldable when pressed, yet has sufficient stiffness to maintain the fullness of the key in the absence of pressure thereon. A lower layer of thin, flexible plastic material  66  of about 10-20 mil thick PVC, or the like, may be disposed across the bottom of the key  60 , as shown in  FIG. 1 . The key may be one of a plurality of such keys on a signal generator  70 , which may be, in one embodiment, arrangable on the face of a force pad  68 , which pad  68  utilizes “pressure” to generate a signal therewithin, as is shown in a side-elevational view, in  FIG. 2 . 
         [0025]    The signal generator shown in  FIG. 1  may have a conductive means arranged therewithin. Such conductive means may be comprised of a conductive foam material  72  as shown in  FIG. 3 . The foam may be conductive by virtue of a mix of metallic powder  74  in a suspension within the foam  72 . A pair of electrodes  76  and  78  are shown arranged on the inner or lower side of the upper layer  62  of the flexible, plastic film. When the key  60  is distorted or compressed by an outside stroke of force, the density of the conductive components within that enclosed key  60  becomes high enough to carry a signal between the electrodes,  76  and  78 . The current path between the electrodes  76  and  78 , is thus complete. The electrodes  76  and  78 , are part of a proper circuit, not shown, for sending the desired signal to an attached electrical device, also not shown. 
         [0026]    Conductive strips are also shown in  FIG. 4 , wherein strip electrodes  80  are also arranged at a lower or base portion  82  of the conductive foam  72 . Spot secondary conductive components  83 , arranged within the foam  72 , or on a base  73  of the generator  70 , are connected to a proper response circuit, to provide directionality in the form of pointing device. Skewed pressure or distortion on one or more of the keys  60  will cause contact with, and hence signal transmission in appropriate spot electrode components such as may be disposed about the lower periphery of the appropriate keys  60 , thus permitting movement of a cursor or the like, by sideways or skewed movement of the key  60 , by energizing by contact, the particular secondary components  83 , to which the proper circuit may be attached. 
         [0027]    In a further embodiment, thin trace metallic conductors  84  may be disposed within the foam  86 , adjacent voids  88  therein, which conductors are then in contact when the key  60  is pressed or distorted by an outside force to create an electrical signal path therewithin, as shown in  FIG. 4   a . The conductors  84  are connected through thin wires  85 , to a processor unit, not shown, to complete the data circuit. The foam  86  may, in this embodiment, also have a conductive powder dispersed therethrough, to further increase conductivity when the key  60  is compressed. Such conductivity is increased in proportion to the force applied to the movement of the key  60 , because of a decrease in resistance due to the compaction and condensing of the conductive components of the foam. Similar cursor moving characteristics may be observed if the conductive components are strain gages or multiple corresponding resistors in a parallel circuit arranged on multiple keys, as described further hereinbelow. 
         [0028]      FIG. 4   b  shows a key  60  enclosing a foam cell material  90  having a upper foam layer  91  of high density conductive material  92  therein, and a lower layer of foam  93 , of lower density conductive material  94  therein. The conductivity of the materials  92  and  94  require a higher pressure or distortion in order to effect the respective signal conducting capabilities. Such conductivity may also be effected by differing resilience/stiffness of the respective foam cells in each layer. This arrangement provides for separate signals, depending upon the amount of force/distortion applied to a key  60 . 
         [0029]      FIG. 5  shows a further compressible key  60  having a pressurized fluid or gas  110  therein. The upper layer  62  in this embodiment, has a plurality of strain gauges  112  spaced on its inner surface, each connected to a proper circuit  114  connected to a processor unit, not shown. These gauges  112  may be utilized with a relatively rigid key, or with a foam or gas filled key in a manner of the earlier embodiments, to indicate a direct or a skewed force against the key  60 . 
         [0030]    These expandable key signal generators  58  may be stored in a collapsed or rolled up configuration, as shown in  FIG. 2   a . The signal generator  58  may have a valve  120  (i.e. a “duckbill” valve or the like), on one end thereof. As the rolled-up signal generator  58  unfurls, the material inside, be it foam or the like, begins to expand of its own nature, as shown in  FIG. 2   b . The valve  120  remains open, as shown in  FIG. 2   c , taking in gas/air, as the flexible upper and lower layers of the signal generator  58  are pushed apart from inside, until the expansion of the signal generator  58  is complete, as shown in  FIG. 2   d . The valve  120  may then be closed, (or sealed of its own accord as with a duckbill valve), thus trapping the air and the foam in which it is trapped, in its expandedmost configuration. Appropriate connectors, not shown, are attached to the conductive means within the signal generator  58 , to direct the signals to a proper external electric component, not shown. The connective means may be comprised of wires, trace metal strips, or optical fibers. 
         [0031]    A further aspect of one embodiment of the present invention also involves the sideways (skewed) directed force or eccentric bias typically provided to a standard alpha/numeric key when a keyboard operator presses that particular key on a keyboard. If that one key were able to move the position of the cursor on a monitor, such cursor movement would be haphazard and random when that particular key was depressed. However, if all or most of the regular alpha/numeric keys on a keyboard were made directionally sensitive through a circuit arrangement associated with each key, and when more than one such key was depressed in a skewed manner, then a computer keyboard operator could effect cursor positioning by the laying of two or more of his/her fingers on the top of the “regular” keys and skewedly depressing a plurality of those keys. This effects a summation of a plurality of resistances created when a plurality of those regular keys are moved with a sideways direction/component of motion, as shown by the arrows labeled “R-L”, as shown in  FIG. 6 . One of the exemplary additive systems embodying this concept is shown in  FIG. 6 , wherein a plurality of keys  160  represent a keypad  130 , all of which may be formed unitarily from a layer of flexible plastic material, as aforementioned. A plurality of primary contact points  132 , properly part of a common circuit  133  for each of the keys  160 , are disposed about the lower peripheral edge of each key  160 . Each of the primary contact points  132  are spaced slightly apart from a secondary contact point  134 . Each secondary contact point  134  is connected to a resistor R 1  or R 2  etc, all around the periphery of the key  160 . Each resistor R 1  of each key  160  is further connected in parallel to every other resistor R 1 , as shown in  FIG. 6 . Each combined resistor R 1 +R 1 +R 1  . . . is then in electrical communication with a proper computer circuit processing unit  80 , which itself is in communication with a monitor  82 . A similar circuit is arranged for each other resistor R 2 , R 3  etc. around the lower periphery of each key  160 . Furthermore, in a still further embodiment, the proportionally conductive foam or strain gages may be similarly connected in a parallel arrangement with similar effect, or they may be connected to a logic device, not shown, which senses the change in resistance of the keys and converts that output to a corresponding digital signal which in turn moves the cursor on the monitor  82 . 
         [0032]    Thus a computer operator may effect cursor positioning on the monitor  82 , (in addition to the standard data generated when a key  160  is pressed in the “usual” way, which may include being mounted on a support post  162 , and connected to its own circuit  164 ), by skewedly pressing a each of a plurality of keys  160  in a generally common direction, to effectuate simultaneous energization of corresponding components (R 1  for each key  160 , or R 2  for each key  160  etc.) to effect cursor motion in a desired direction on the monitor  82 . Multiple resistance in a parallel scheme shown in  FIG. 6 , provides a stronger signal when more keys  160  are skewedly pressed, thus providing the means to move a cursor faster, depending on the number of keys  60  or force on several keys, an operator may biasedly press or move simultaneously. 
         [0033]    Thus what has been shown in a preferred embodiment, is a signal generating device which may be unfurled or expanded from a compressed configuration into a flexible functional orientation. The device may utilize compressible or distortable keys which are maintained in an erect state by an expanded fluid or foam material swelled therewithin. The device may also be able to provide pointing, or cursor movement on a monitor, merely by the skewed pressing of a plurality of keys on a keyboard, which is particularly useful on lightweight portable keyboards, where simplicity, convenience and storability are desired. Such cursor movement may also be accomplished by adapting alpha/numeric keys of a standard keyboard with the secondary circuit according to one embodiment of the present invention so provide an indication when such keys are being given a sideways directed force. The additive secondary circuit is arranged so as to sense a tilted or sideways biased force against a plurality of keys to direct a signal to the central processing unit, to move a cursor or pointer in a connected monitor. There is no need for a “mouse”, joy-stick, roller-ball or other contrivance to get in the way of keeping an operator&#39;s hands on the keyboard. Such an arrangement for cursor movement may also be employed in a conventional “rigid” or hard keyboard, either by placing sensors such as strain gages under the keycaps which define the conventional keys, or on the keyposts which support the keycaps on conventional keyboards, with similar effectiveness for providing electrical signals for the proportional directional movement of cursors, provided that sufficient sideways motion is permitted by the conventional key/key support mechanism.