Abstract:
An apparatus including a plurality of input keys for user interfacing  
     said input keys being relocatably mounted on said apparatus and can be relocated to other positions on said apparatus adapted for receiving said input keys,  
     said input keys include identification means which co-operate with detection means of said apparatus for ascertaining the individual identity of said input keys,  
     said input keys also include indicia for user identification and selection.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to electronically controlled devices, appliances and apparatus with data input or user interfacing terminals. More specifically, although of course not solely limited thereto, this invention relates to electronic devices with key-location reconfigurable input terminals. This invention also relates to methods for reconfiguration of data input keys on data input terminals of electronic devices, appliances and apparatus and electronic devices, appliances and apparatus incorporating same.  
         BACKGROUND OF THE INVENTION  
         [0002]    Electronic devices, appliances and apparatus (collectively “electronic apparatus”) are frequently provided with data input or user interfacing keyboards or terminals. For example, computers are provided with keyboards for data entry as well as user interaction. Many industrial, scientific and medical apparatus nowadays are usually digitally or microprocessor controlled so that control or data input terminals are required to set apparatus or system parameters. With the ever decreasing costs of microprocessors and peripheral devices, domestic or household appliances nowadays are also widely equipped with microprocessors. As a result, input keyboards for controlling are also more commonly found on such appliances.  
           [0003]    In general, data input or user interaction terminals (collectively for succinctness, the “keyboards”) are generally provided with a plurality of data input or command keys. The keys are generally provided with physical indicia, for example, symbols, alphabets, characters for user identification and selective actuations. Such indicia may be in the form of two-dimensional labels or three-dimensional contoured patterns. Typically, the data input or controlled keys are disposed or arranged in a fixed manner pre-determined by the manufacturers. An operator using the keyboards is therefore required to learn, memorize and be accustomed to the key arrangements in order to perform efficient data entry or interactive commands.  
           [0004]    Furthermore, where alphanumerical keyboards are provided with such computers, appliances or apparatus, they are usually the “QWERTY” type as the basic version of the QWERTY keyboard has been around since the 19 th  century. However, it is known that the QWERTY configuration is inefficient and new keyboard arrangements, for example, the Dvorak simplified keyboard, have been developed to reduce errors and increase typing speed. Thus, an operator familiar with the Dvorak keyboard may be found provided with the QWERTY and vice versa. For devices or apparatus with numerical inputs, for example, mobile phones, it is also known that the various arrangements of the 0-9 numerical keys can cause user inconvenience and confusion.  
           [0005]    As computers and other electronic apparatus are usually factory provided with a specific data entry keyboard, this inevitably means a sacrifice in speed or accuracy for operators not particularly proficient with the keyboard provided. While software is available to convert or reconfigure the disposition of the alphanumerical keys or other keys on a keyboard from, for example, QWERTY to the Dvorak keyboard or other arrangements, the individual keys are generally labelled with specific numerals or alphabets which may affect the operator in the course of data entry or even confuse the unaware.  
           [0006]    Hence, it will be desirable if there can be provided keyboards with reconfigurable keys which alleviate the shortcomings of conventional alphanumeric or other keyboards. Such keyboards should be easily reconfigurable without undue complexity or without the need of specialized tools so that individual operators can conveniently reconfigure the keyboards to maximize their performance.  
         OBJECT OF THE INVENTION  
         [0007]    Hence, it is an object of the present invention to provide reconfigurable keyboards and apparatus incorporating same which alleviate the shortcomings associated with conventional keyboards. At a minimum, it is an object of the present invention to provide the public with a choice of an alternative reconfigurable keyboard.  
         SUMMARY OF THE INVENTION  
         [0008]    According to the present invention, there is provided an apparatus including a plurality of input keys for user interfacing  
           [0009]    said input keys being relocatably mounted on said apparatus and can be relocated to other positions on said apparatus adapted for receiving said input keys,  
           [0010]    said input keys include identification means which co-operate with detection means of said apparatus for ascertaining the individual identity of said input keys,  
           [0011]    said input keys also include indicia for user identification and selection.  
           [0012]    Preferably, said apparatus includes a keyboard housing and said input keys being mounted on said keyboard housing, said keyboard housing includes a distributed detection network for identifying the input key being physically actuated.  
           [0013]    Preferably, said input keys being detachable from and re-insertable onto said keyboard.  
           [0014]    Preferably, said input keys being reconfigurable by sliding along predetermined tracks or channels on said keyboard housing.  
           [0015]    Preferably, said input keys include electrical identification characteristics for electrical signal identification by said detection means.  
           [0016]    Preferably, said input keys include electrical identification means and said distributed detection network includes corresponding electrical characteristic detection means.  
           [0017]    Preferably, said distributed network includes a plurality of detection means corresponding to the number of said input keys, said detection means includes a detection matrix for ascertaining the identity of said input keys.  
           [0018]    Preferably, said detection matrix includes a plurality of contact pads and said input keys include contact means disposed corresponding to a predetermined selection of contact pads on said input housing for identification.  
           [0019]    Preferably, the contact pads on said detection matrix are disposed on a plurality of piled circuit boards wherein the contact pads on one circuit board surrounds that on the others.  
           [0020]    Preferably, the identification on said input keys include optically recognizable patterns and said detection means include pattern recognition means.  
           [0021]    According to a preferred embodiment of the present invention, there is therefore provided an apparatus including a plurality of relocatable input keys, wherein said input keys include physical indicia for user identification and selection, said input keys being provided with identification means and said apparatus include common detection means for ascertaining the identity of said input keys.  
           [0022]    According to a further aspect of the present invention, there is provided a detachable key for use with a key location-reconfigurable keyboard including an outer key housing, a resilient means, an intermediate member and an identification means, said identification means being characteristic of the identity of said detachable key, said outer means includes means for detachably engaging with the housing of said key-reconfigurable, said intermediate member including means to co-operate with said housing of said location-reconfigurable keyboard and said housing of said detachable key so that said outer housing being resiliently movable towards said keyboard, said resilient means being disposed between said outer housing and said intermediate member so that relative movement between said outer housing of said detachable key and said intermediate member being under spring urge. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0023]    Preferred embodiments of the present invention will be explained in further detail below by way of example and with reference to the accompanying drawings in which:— 
         [0024]    [0024]FIG. 1 is an example of an alpha-numerical keyboard of the present invention configured according to the conventional “QWERTY” arrangement,  
         [0025]    [0025]FIG. 2A is a cross-sectional view along the section line A of the keyboard of FIG. 1,  
         [0026]    [0026]FIG. 2B is the enlarged view of the encircled portion of FIG. 2A,  
         [0027]    [0027]FIG. 3A shows the plan view of a keyboard of a second embodiment of the present invention,  
         [0028]    [0028]FIG. 3B shows schematically the partial layout of the channels or tracks of the keyboard of FIG. 3A as well as the corresponding projections of some of the keys on the layer underneath the top housing of the keyboard,  
         [0029]    [0029]FIG. 4A is a cross-sectional view showing the keyboard of FIG. 3A along the section line A-A,  
         [0030]    [0030]FIGS. 4B and 4C show respectively the enlarged view of the enclosures marked “A 1 ” and “B 1 ” of FIG. 4A,  
         [0031]    [0031]FIG. 4D is a cross-sectional view showing the cross section of some of the keys of the keyboard of FIG. 3A,  
         [0032]    [0032]FIG. 4E is an enlarged view showing the enclosure marked “C 1 ” of FIG. 4D,  
         [0033]    [0033]FIGS. 4F, 4G,  4 H and  41  show various component parts of the input key and the circuit board for use in the present invention,  
         [0034]    [0034]FIG. 5A illustrates the circuit board layout of part of the detection means of the keyboard for the present invention,  
         [0035]    [0035]FIG. 5B is an enlarged view of enclosure marked “D” of FIG. 5A,  
         [0036]    [0036]FIG. 6A shows the circuit board layout of another part of the detection means of the present invention,  
         [0037]    [0037]FIG. 6B shows in more detail the enlarged view of the enclosure marked “E” of FIG. 6A,  
         [0038]    [0038]FIG. 7A shows the circuit board layout of another part of the detection means of the circuit board of the present invention,  
         [0039]    [0039]FIG. 7B is an enlarged view of enclosure marked “F”,  
         [0040]    [0040]FIG. 8A, FIG. 8B and FIG. 8C illustrate respectively the parts of an input key of a first example, the assembled form and the correspond projection on detection matrix,  
         [0041]    [0041]FIG. 9A, FIG. 9B and FIG. 9C illustrate respectively the parts of an input key of a second example, the assembled form and the correspond projection on detection matrix,  
         [0042]    [0042]FIG. 10 illustrates inter-relationship of various parts constituting the detection matrix,  
         [0043]    [0043]FIG. 11 illustrates the inter-relationship between actuation key and the underlying detection means of the present invention, and  
         [0044]    FIGS.  12 A- 12 E show other possible combination of the identification counter points on actuation and the corresponding detection matrix projection.  
         [0045]    [0045]FIG. 13A shows an exploded view of a first preferred embodiment of a removable key sub-assembly of the present invention,  
         [0046]    [0046]FIG. 13B is a longitudinal view of the component parts of two adjacent keys and the correspondence receiving structure on a keyboard,  
         [0047]    [0047]FIG. 13C shows a cross-sectional view of one of the removable keys sub-assembly of FIG. 13A when mounted onto a keyboard,  
         [0048]    [0048]FIG. 13D is a perspective view showing a corresponding structure on a keyboard for receiving the key of FIG. 13A,  
         [0049]    [0049]FIG. 13E is an exploded view of the component parts  313  and  314  of the sub-assembly,  
         [0050]    [0050]FIG. 13F shows the assembled form of the components  313  and  314 ,  
         [0051]    [0051]FIG. 13G is a partially exploded view of FIG. 13D,  
         [0052]    [0052]FIG. 14A is an exploded view of a removable key of a second preferred embodiment of the present invention,  
         [0053]    [0053]FIG. 14B is a cross-sectional view of two of the keys of FIG. 14A when mounted on a keyboard,  
         [0054]    [0054]FIG. 14C is a cross-sectional view along a substantially orthogonal direction of FIG. 14B,  
         [0055]    [0055]FIG. 14D is a perspective view showing the corresponding structure on a keyboard for receiving the key sub-assembly of FIG. 14A, and  
         [0056]    [0056]FIG. 14E shows a longitudinal cross-sectional view of the components of the keys of FIG. 14A and part of the keyboard. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0057]    Referring firstly to a first preferred embodiment of a keyboard of the present invention, the keyboard  100  includes a plurality of input keys  110  which may be alphabetical keys  1 ; 11 , numerical keys  112 , function keys  113 , control keys  114  and other appropriate keys. The input keys  110  (including generally the alphanumeric keys, function keys and control keys) are mounted on a keyboard housing  120  which may be rigid, flexible, foldable or resilient. It will be noted from the description below that the locations of the input keys  100  are reconfigurable at various predetermined locations to be determined by a user. A more detailed cross-section of the key arrangements of the keyboard  110  are shown in FIGS. 2A and 2B as well as FIGS.  4 A- 4 H.  
         [0058]    Referring, for example, to FIGS. 2B to  4 B, the input keys  110  include a body  115  with a pair of resilient arms  116  with inverted hooks. The keys  110  are mounted on the housing of the keyboard against spring bias  117  and the pair of resilient arms are provided to guide the movement of the keys along a direction to actuate and de-actuate the keys  110 .  
         [0059]    As shown in FIGS. 4B to  4 F, the input key  110  includes a cap portion  118  and the stem portion  119 . An operator activates the input key  110  by pressing downwards on the top of the cap  118  which then moves the stem portion  119  downward to make contact with or trigger the associated detection means on the keyboard or apparatus. A hard plastic key housing  120  may be provided to receive the key body  115 . A collar means may be formed on the housing to surround the stem to allow guided relative translation movements of the key body  115  along the actuation direction. A washer  150 , for example, a soft plastic washer, is inserted into the stem portion  119  to shield the detection circuitry on the keyboard housing  120  to prevent dust or other contaminants from entering the electrical contact areas and to hold the keys in place. Each of the input keys  110  are generally provided with physical indicia to enable an operator to identify and select the appropriate keys. Such physical indicia may, for example, include two dimensional or three-dimensional labels corresponding to the symbols representing the alphabets, numerals and control or function options.  
         [0060]    To enable flexible reconfigurability, each input key  110  is provided with a characteristic identification means which, when incorporated or coupled with the corresponding detection means provided on the keyboard or apparatus, will provide sufficient identification information enabling the decision circuitry, for example, the embedded microprocessor, to be informed of the specific key being actuated. In the present preferred embodiments and as shown more particularly in FIGS. 8A to  9 C, each input key  110  includes an identification board  130  which includes a pair of contact pads  131 ,  132  on the underside which is the side opposite the detection board  200  on the keyboard housing  120 . The contact pads  131 ,  132  include, for example, contact conductive bumps for more effective and reliable contact and are disposed so that their projections coincide with a specific grid combination on the corresponding detection means on the keyboard detection circuitry as shown in FIGS. 8C and 9C.  
         [0061]    The detection means as shown in the present embodiments include a matrix of orderly arranged conductive grid array  140 . For example, the physical locations of the conductive bumps formed on the underside of the identification board  130  of FIG. 8A correspond to row 1 column 1 and row 1 column 5 of the detection grid array  140  of FIG. 8C. Similarly, the projection of the identification conductive bumps  131 ,  132  on the input keys of FIG. 9A corresponds to locations row 1 column 1 and row 3 column 3 of the detective grid array, as shown in FIG. 9C.  
         [0062]    By providing the resilient arms  116  as shown in FIG. 2B, the input keys  110  can be detachably removed from one location on the keyboard to another without tools. As the physical indicia and the identification means are attached with the individual input keys, the relocated keys will bring with their relocation the associated identification characteristics. Thus, for example, the alphabet key “A” in the conventional QWERTY keyboard can be relocated to position, say, for example, Y, of the new keyboard as reconfigured according to the wish of the operator.  
         [0063]    Referring to FIG. 11 showing in more detail the detection grid array  140  as described in FIGS. 8C and 9C, it will be noted that the detection grid array  140  includes a plurality of conductive pads  141  arranged in an orderly manner. More specifically, the present detection grid array  140  example includes a total of 25 conductive pads arranged in a square grid array comprising 16 conductive pads arranged on the outer square, 8 conductive pads arranged on the intermediate square and a single conductive pad in the innermost squares. In order to provide the maximum contact area for each conductive pad  140  on the detection means and to provide a simplified signal routing for ascertaining a particular combination of conductive pads for specific key identification, the detection means in the present embodiments comprises three overlapping layers  210 ,  220  and  230 . In the lower most layer  210 , a grid array with 16 conductive pads arranged along the outside edges is laid out. In the second circuit board  220 , a total of 8 conductive pads are distributed on the outer edges of a square corresponding to the intermediate square as shown in FIGS. 6B and 10 are provided. At last, a third circuit board  230  with a single conductive pad for identification must be provided. The three circuit boards are plied together so that the collective conductive pads are disposed together to form an orderly square grid or matrix manner  140  as shown in FIG. 10.  
         [0064]    An example circuit board layout of the first circuit board layer  210  is shown in FIGS. 5A and 5B. The corresponding second circuit layer layout  220  is shown in FIGS. 6A and 6B and the third layer  230  comprising a single conductive pad is shown in FIGS. 7A and 7B. While the formation of the detection means by the use of the overlying circuit boards will simplify signal routing, it will be understood that the detection means or the detection circuitry can be formed on a single or a multi-layered circuit board with appropriate signal routing. Also, the circuit boards for the detection circuitry or means can be rigid or flexible circuit boards while flexible boards are preferred as their use can reduce the overall thickness of the detection circuitry.  
         [0065]    In assembling the detection circuitry, the three detection circuit boards with common guiding means, for example, guiding apertures or other appropriate means are assembled together and the output signals, through the signal tracks  250 , from each of the circuit boards are combined together for determining the identity of the input G being actuated.  
         [0066]    In the present example, as there are 25 detection conductive pads, a total of  25 C 2  combinations are available for individual key identifications. On the other hand, where a smaller number of key combinations are required, for example, when  16 C 2  or  8 C 2 , are required, a single circuit board may be sufficient to provide the necessary combinations. Of course, the actual number of boards and the number of conductive boards distributed on each identification circuitry will also depend on the minimum acceptable spacing between adjacent conductive pads and the maximum foot-print acceptable for each key detection circuitry. When the input key of FIG. 2B is to be removed from the keyboard, the pair of resilient arms are to be pressed towards each other to provide sufficient clearance for the removal passage of the key body. As the locking arms are resilient with a pair of inverted hooks at their lowest extremes, the keys can be reinserted and engaged on the keyboard at the appropriate key location and locked in place.  
         [0067]    Referring now to FIGS. 3A and 3B showing a second preferred embodiment of the present invention, the keyboard  200  housing is provided with a plurality of interconnected tracks  210  so that the keys are slidably movable along the channels or tracks. By moving the input keys, for example, in a manner as shown in FIG. 3A, the keys can be relocated. As the input keys are provided with identification means similar to the keys of the first embodiment, and a similar detection circuit board is provided underneath the input keys, the input keys can be identified by the underlying detection circuitry irrespective of the instantaneous location of the keys. Of course, the tracks are provided with location indication means confirming that the input keys are in proper alignment with the underlying detection circuitry to ensure proper identification. Thus, with the use of a keyboard housing having a plurality of interconnecting key channels or tracks, the keys can be reconfigured by sliding along those tracks and channels while minimizing the risk of key loss.  
         [0068]    It will be noted that while electrical identification means by way of a pair of conductive bumps are formed on the lower side of each individual input keys, it will be understood that other identification means, for example, optical or pattern recognition means can be used so that a specific pattern can be formed on the underside of the input key and a corresponding pattern recognition means can be used to ascertain the specific identity of the keys being actuated.  
         [0069]    FIGS.  12 A-E shows a plurality of combinations of the conductive bumps indicating the possible variation of the foot-prints of the conductive bumps on the input key corresponding to the detection grid arrays. Of course, the conductive grids may be connected with a conductive track or specific resistors so that the identity of the keys can be identified by the range of resistance measured between the two conductive bumps. As a further example, the identity of the input keys can be identified by other electrical characteristics such as, for example, resistance or impedance between contact terminal for identification purpose without loss of generality.  
         [0070]    [0070]FIGS. 13A to  13 G show in more detail a first preferred embodiment of a removable key sub-assembly of the present invention. The key  310  includes an upper housing (or an outer cap)  311 , a resilient member  312 , an intermediate member  313 , an inner housing  314  and an identification means  315 . The identification means  315  includes a contact member which is equivalent to the identification board  130  described above and includes a pair of identification contact pads  131 ,  132  on the underside for making contact with the circuitry on the main keyboard housing. The contact member of the identification means is attached to the bottom of the inner housing  314  so that the contact pads on the contact member will make electrical contacts with the electronic circuitry on the keyboard housing when the inner housing  314  is adequately depressed.  
         [0071]    The intermediate member  313  has a wing-shaped extension at its lateral sides so that the intermediate member  313  has generally a T-shaped cross-section. To assemble the removal key  310 , the deformable T-shaped intermediate member  313  is inserted into the inner housing  314  through the side aperture  316  of the inner housing  314 .  
         [0072]    The lateral dimension of the T-shaped intermediate member  313  being designed so that when the key sub-assembly  310  is inserted onto the key receptacle  322  of the keyboard housing  321 , the protruding portions of the T-shaped intermediate member  313  will be trapped by a catching mechanism ( 325 ,  326 ) formed on the inner surface of the key receptacle  324 , thereby generally preventing the intermediate member  313  to move relative to the catching member.  
         [0073]    After the intermediate member  313  has been inserted into the inner housing  314 , the resilient member  312  is placed onto top surface of the intermediate member  313  and in the confined space between the outer cap  311  and the intermediate member  313 . The outer cap  311  is then mounted onto the inner housing  314 . A pair of latching mechanism  317  formed on the inside of the outer cap  311  and the inner housing  314  will cause the two housings to attach, for example, by snap-fit, thereby forming a sub-assembly of a removable key comprising the parts  311 - 315 .  
         [0074]    When the removable key sub-assembly  310  has been formed, the resilient member  312 , which can for example include a bell-shaped silicone or rubber member or a spring, is being trapped between the intermediate member  313  and the outer housing or the outer cap  311 . Furthermore, the intermediate member is movable along the axial direction of and relative to the inner housing between the top and bottom ends of the side apertures  316 .  
         [0075]    On the keyboard housing  321 , there are formed a plurality of removable key receptacles  322 . Two key receptacles have been shown in the Figure as a convenient example. The key receptacle  322  includes a peripheral wall  323  which is shaped and dimensioned to correspond to that of the inside of the lower part of the outer housing  311 . The key receptacle  322  includes a catching mechanism comprising protrusions  325  and  326  on opposite sides of the key receiving aperture  324 . The catching mechanism comprises the protrusion  325  and  326  which are dimensioned so that when the removal key sub-assembly  310  is inserted into the aperture  324  of the key receptacle  322 , the protruding edges of the intermediate member  313  will be caught and trapped by the catching mechanism so that the intermediate member will be prevented from moving along the axial direction of the aperture  324 .  
         [0076]    When the outer cap  311  is depressed, parts  311 ,  314  and  315  will move downwards relative to the key receptacle  322  until the identification means makes contact with the circuit board on the keyboard housing. As the intermediate member  313  is restrained from moving along the axial direction of the aperture  322 , the space between the top of the intermediate member  313  and the outer cap is reduced, thereby axially compressing the resilient member  312 . When the downward depressing force has been removed from the outer cap  311 , the stored resilient energy in the resilient member will be released, thereby pushing the outer cap  311  and the connected parts  314  and  315 , away from the circuitry on the keyboard housing, thereby terminating the contact.  
         [0077]    It will be appreciated that the catching mechanism  325  and  326  and the engaging portions on the T-shaped intermediate member are made for easy insertion and removal while at the same time provides sufficient resistance to prevent inadvertent release of the removable key sub-assembly  310  when the stored compression energy is released from the resilient member  312 .  
         [0078]    [0078]FIGS. 14A to E show in more detail a second preferred embodiment of a removable key sub-assembly  330  of the present invention. Similar to the structure of the first preferred embodiment of a removal key sub-assembly  310  described above, a removable key sub-assembly  330  includes an outer housing  331 , a resilient member  332 , an intermediate member  333 , an inner housing  334  and contact identification means  335 . The components in this sub-assembly  330  are generally identical to that of the first preferred embodiment  310  with the primary exception of the inner housing  334 .  
         [0079]    Instead of the intermediate member  333  being engaged with a latching mechanism formed on the receptacle, the inner housing  334  includes engagement means  337  for latching with corresponding engaging means on the key receptacle  344 . Hence, the structure of this removal key sub-assembly  330  is generally identical to the first preferred embodiment  310  except that a movement limitation means  337  is formed on the inner housing  336 . The movement limitation means  337  and the inner housing  336  in the present embodiment includes protruding teeth formed on opposite sides of the inner housing  336  which are to be trapped or caught by restraining means or latching mechanism formed in the key receptacle  344  which limits the upward axial freedom of movement of the inner housing  336 .  
         [0080]    The intermediate member  333  has a generally T-shaped cross-section with protruding parts the dimension of which exceeds that of the peripheral wall of the key receptacle  344 . Thus, the peripheral wall of the key receptacle  344  will restrict the range of downward movement of the intermediate member  333 . Thus, when the key sub-assembly  330  is inserted into the key receptacle  344 , the catching means on the key receptacle  334  will restrict the upward movement of the inner housing  336  while the upper edges of the peripheral wall of the key receptacle  344  will prevent excess downward axial movement of the intermediate member  333 .  
         [0081]    When the outer cap  331  is being depressed, the entire sub-assembly  330  will move downwards until the intermediate member  333  is being restrained by the peripheral wall  345  at which point the outer cap  331 , the inner housing  334  and the contact identification means  335  will move further downwards with the intermediate member  333  will begin to be detached from the other parts of the sub-assembly.  
         [0082]    When the depression force acting on the outer cap  331  has been removed, the compressive energy stored in the resilient member  332  will be released, thereby moving the sub-assembly upwards. After the sub-assembly has moved axially upwardly for a predetermined range, the limiting means on the receptacle may prevent further upward movement of the inner housing and the stored energy in the resilient member will continue to move the outer cap  331  further upwards until all the stored energy has been released.  
         [0083]    While the present invention has been explained by reference to the preferred embodiments described above, it will be appreciated that the embodiments are only illustrated as examples to assist understanding of the present invention and are not meant to be restrictive on its scope. In particular, the scope, ambit and spirit of this invention are meant to include the general principles of this invention as inferred or exemplified by the embodiments described above. More particularly, variations or modifications which are obvious or trivial to persons skilled in the art, as well as improvements made on the basis of the present invention, should be considered as falling within the scope and boundary of the present invention.  
         [0084]    Furthermore, while the present invention has been explained by reference to a keyboard, it should be appreciated that the invention can apply, whether with or without modifications, to other device or apparatus without loss of generality.