Key panel and strip switch assembly configurations having variable aspect ratios and method of making

Information

  • Patent Grant
  • 6365848
  • Patent Number
    6,365,848
  • Date Filed
    Friday, February 25, 2000
    24 years ago
  • Date Issued
    Tuesday, April 2, 2002
    22 years ago
Abstract
A key panel includes a key panel configuration having a number of switch locations arranged in a pattern so as to define an aspect ratio for the key panel configuration. A strip of switch material having an aspect ratio that is greater than the aspect ratio of the key panel configuration and having a number of switches that is at least equal to the number of switch locations for the key panel configuration is provided with at least one fold therein so as to arrange the number of switches on the strip of switch material in the pattern defined by the key panel configuration.
Description




FIELD OF INVENTION




The present invention relates to key panels in general and more specifically to a key panel formed from a single strip of switch material and a method for making the key panel.




BACKGROUND




Key panels or keyboards have been used for decades to provide input and control instructions to electronic devices and systems. Early key panel systems were discrete systems, typically comprising an array of individual mechanical switches arranged and mounted so as to form the desired key panel configuration. For example, early QWERTY (e.g., typewriter-style) key panel systems were constructed according to this architecture. However, besides being cumbersome, heavy, and prone to malfunction due to foreign object contamination, such discrete type key panel or keyboard systems are expensive and difficult to produce.




Partly in an effort to solve some of the problems associated with discrete component key panel systems, key panel systems have been developed in which the various switches are provided on thin, flexible substrates or membranes. Such key panel systems are often generically referred to as membrane type key panel systems. While many different types of membrane type key panel systems exist and are being used, a typical membrane type key panel system comprises a laminated or layered structure in which a bottom membrane layer or sheet is provided with a plurality of switch elements that correspond to each desired input key. An overlying flexible layer or membrane may be provided with one or more raised portions or “domes” thereon that are aligned with the switch contacts provided on the bottom layer or membrane. Each switch on the bottom membrane may be actuated by depressing the corresponding dome on the overlying or top layer. Membrane type key panels of the type just described have become very popular and are widely used in modern electronic devices and systems due to their reliable operation, light weight, and rugged construction.




One problem that remains with such membrane type key panel systems is that they are not readily adaptable to varying panel or keyboard configurations. As an example, a currently available membrane type key system is produced as a two dimensional sheet or panel having a size and shape that corresponds to the specific key panel layout for the particular device in which the key panel is to be used. Therefore, if the key panel layout is changed, an entirely new sheet or panel of the switch membrane material must be produced that corresponds to the changed key panel layout. Moreover, if a user desires to utilize a key panel configuration wherein the keys are placed around the periphery of the panel, such as for example, if the keys are to be placed around a centrally located two dimensional display device (e.g., a CRT or and LCD display), the sheet material located in the corresponding central region of the key panel will need to be removed, thus wasted, in order to accommodate the display device. Such waste increases the overall cost of the key panel device. Another disadvantage associated with currently available membrane type key panel systems is that two dimensional sheets or panels are difficult to ship and store, particularly if the key panel in which they are to be used is relatively large.




SUMMARY OF THE INVENTION




A key panel according to one preferred embodiment of the invention includes a key panel configuration having a number of switch locations arranged in a pattern so as to define an aspect ratio for the key panel configuration. A strip of switch material having an aspect ratio that is greater than the aspect ratio of the key panel configuration and having a number of switches that is at least equal to the number of switch locations for the key panel configuration is provided with at least one fold therein so as to arrange the number of switches on the strip of switch material in the pattern defined by the key panel configuration.




Also disclosed is a method for fabricating a key panel that comprises the steps of: Selecting a key panel configuration having a number of switch locations arranged in a pattern so as to define an aspect ratio for the key panel configuration; selecting a strip of switch material having an aspect ratio that is greater than the aspect ratio of the key panel configuration, the strip of switch material also having a number of switches that is at least equal to the number of switch locations for the key panel configuration; and folding the strip of switch material so as to arrange the number of switches provided on the strip of switch material in the pattern defined by the key panel configuration.











BRIEF DESCRIPTION OF THE DRAWING




Illustrative and presently preferred embodiments of the invention are shown in the accompanying drawing in which:





FIG. 1

is an exploded perspective view of a key panel assembly according one embodiment of the present invention showing the positional relationship between a strip of switch material used to form the key panel, a key panel configuration, and a key panel bezel;





FIG. 2

is a front view in elevation of the key panel configuration shown in

FIG. 1

showing the switch locations and their arrangement in a switch pattern;





FIG. 3

is a front view in elevation of the strip of switch material before it is folded into the key panel configuration;





FIG. 4

is an enlarged sectional view in elevation of the key panel assembly shown in

FIG. 1

;





FIG. 5

is a side view in elevation of a second embodiment of a strip of switch material having an offset fold to make substantially coplanar the various switch domes forming the key panel configuration;





FIG. 6

is a front view in elevation of a third embodiment of a strip of switch material having two single folds to position the various switch domes on opposite sides of the strip of switch material; and





FIG. 7

is an enlarged sectional view in elevation of a fourth embodiment of a key panel assembly according to the present invention.











DETAILED DESCRIPTION OF THE INVENTION




A key panel assembly


10


according to one preferred embodiment of the present invention is best seen in FIG.


1


and may comprise a strip of switch material


12


folded so that it conforms to a desired key panel configuration


14


. As will be described in greater detail below, the key panel configuration


14


is not necessarily a physical element but instead represents a desired configuration for the key locations for a desired device (not shown), such as a portable or hand-held scanner device. By way of example, in the embodiment shown in

FIG. 1

, the key panel configuration


14


may comprise a generally rectangular shape having a number of switch locations


16


arranged in a generally U-shaped pattern


18


. The arrangement of the switch locations


16


in the pattern


28


defines an aspect ratio for the key panel configuration


14


. With reference to

FIG. 2

, the aspect ratio for the key panel configuration


14


is defined as the ratio of the overall length


20


between the switch locations


16


that are separated by the greatest distance along the length direction and the overall width


22


between the switch locations that are separated by the greatest distance along the width direction. Expressed algebraically, the aspect ratio is the overall length


20


divided by the overall width


22


.




With reference now to

FIG. 3

, the strip of switch material


12


may comprise an elongate, generally flexible member having a front side


21


and a back side


23


. One or more switches


24


are provided on the strip of switch material


12


. The switches


24


on the strip of switch material


12


define an aspect ratio for the strip of switch material


12


. The aspect ratio for the strip of switch material


12


is defined as the ratio of the overall length


26


between the switches


24


that are located at either end of the strip of switch material


12


and the overall width


28


between the switches


24


that are separated by the greatest distance along the width direction. Expressed algebraically, the aspect ratio of the strip of switch material


12


is the overall length


26


divided by the overall width


28


.




The key panel assembly


10


according to the present invention is formed by selecting a strip of switch material


12


having a numerical aspect ratio (i.e., the overall length


26


of the strip of switch material


12


divided by overall width


28


of the strip of switch material) that is greater than the numerical aspect ratio (i.e., overall length


20


of the key panel configuration


14


divided by overall width


22


of the key panel configuration


14


) of the key panel configuration


14


. The strip of switch material


12


should also contain at least as many switches


24


as their are switch locations


16


in the key panel configuration


14


. The strip of switch material


12


is then provided with one or more folds


30


so as to arrange the various switches


24


provided on the strip of switch material


12


in accordance with the pattern


18


defined by the key panel configuration


14


. Stated another way, the strip of switch material


12


is folded so that each switch


24


is positioned at the corresponding switch location


16


provided on the key panel configuration


14


. See FIG.


1


. Once properly configured (e.g., by folding) the strip of switch material


12


may then be incorporated into the device (not shown) in which the key panel assembly


10


is to be used. For example, in one preferred embodiment, the folded and configured strip of switch material


12


may be affixed to a subpanel


42


(

FIG. 4

) associated with the device (not shown) and covered with a control panel bezel


32


(FIG.


1


).




A significant advantage of the key panel assembly


10


according to the present invention is that it allows the key panel


10


to be formed with a single, continuous strip of switch material


12


, thereby eliminating much of the waste typically associated with prior key panels formed from two-dimensional sheets of key switch material (not shown). For example, in the embodiment shown in

FIG. 1

, a key panel fabricated from a two-dimensional sheet (not shown) about the same size as the rectangular key panel configuration


14


would include a large waste area roughly corresponding to an area


34


on the key panel configuration


14


that is devoid of switches. That is, the waste area on the two-dimensional sheet of key panel material would be about the same size as a display window


36


provided on the bezel assembly


32


. The present invention eliminates such waste in that the strip of switch material need not be positioned in the waste area


34


.




Another advantage of the present invention is that it allows key panels having almost any size and shape (i.e., key panel configuration) to be manufactured from a single, continuous strip of switch material


12


by simply folding and bending the strip of switch material


12


as necessary to form the desired configuration. Accordingly, the present invention also eliminates the need to provide separate, and typically custom-designed, two-dimensional key panel sheets for a given product or product line. The present invention thus represents a paradigm shift: It allows membrane type key panels to be fabricated from a single strip of switch material as opposed to using a larger two-dimensional sheet or panel of membrane type switch material.




Still other advantages are associated with the strip of switch material


12


. For example, the flexible nature of the strip of switch material


12


allows the material to be used to form three-dimensional key panel configurations, i.e., configurations wherein switches may be located on a front surface, a side surface, and a back surface of the device. The strip of switch material


12


may also be used with curved key panel configurations in which a given surface of the key panel may be curved in three dimensions.




Having briefly described one embodiment of the key panel


10


, as well as some of its more significant features and advantages, the various embodiments of the key panel according to present invention will now be described in detail. However, before proceeding with the detailed description, it should be noted that only a limited number of configurations and examples for the key panel are shown and described herein. Many other configurations are possible and may be used in any of a wide variety of applications. Indeed, the key panel assembly according to the present invention may be used in almost any configuration and for and device imaginable, be it a currently existing device, or some device yet to be developed. Consequently, the present invention should not be regarded as limited to the particular configurations, applications, and devices shown and described herein.




With the foregoing considerations in mind, one embodiment of the key panel assembly


10


according to the present invention is best seen in

FIGS. 1-4

as it may be used to form the key panel associated with a portable or hand-held scanner device (not shown). The bezel assembly


32


of such a portable or hand-held scanner device is shown in FIG.


1


. As mentioned above, the functional and/or aesthetic requirements of the particular device in which the key panel assembly


10


is to be used will lead a designer to develop a key panel configuration


14


which defines a variety of switch locations


16


arranged in a pattern


18


. Of course, the exact number of switch locations


16


and the particular pattern


18


in which they are arranged will vary from device to device. However, mindful of a few simple design constraints (discussed below) associated with the strip of switch material


12


, a designer will be able to utilize the strip of switch material


12


in almost any key panel configuration


14


that can be imagined.




Continuing now with the description, in the device represented by the example shown in

FIG. 1

, the key panel configuration


14


may comprise a plurality of switch locations


16


arranged in a generally U-shaped pattern


18


. It should be noted that the key panel configuration is not necessarily a physical device or structure and could instead simply comprise a plan or construct used to guide the development of the device and to define the locations of the various switches to be contained in the key panel. Consequently, the present invention should not be regarded as limited to a physical key panel configuration


14


. In the example shown in

FIG. 1

, the key panel configuration


14


may also be provided with a multi-switch location


16


′ which may comprise four individual switch locations


16


″ arranged in a group to define the multi-switch location


16


′. Such multi-switch locations


16


′ may be accommodated by the present invention by providing the strip of switch material


12


with a corresponding grouping


24


′ of individual switches


24


″, as discussed below. Alternatively, such multi-switch locations


16


′ need not be provided.




The pattern


18


of switch locations


16


defining the key panel configuration


14


also define an aspect ratio for the key panel configuration


14


. Referring now to

FIG. 2

, the aspect ratio of the key panel configuration


14


is the ratio of the overall length


20


to the overall width


22


of the switch locations


16


defining the key panel configuration. Stated arithmetically, the aspect ratio of the key panel configuration


14


is the overall length


20


of the key panel configuration


14


divided by the overall width


22


of the key panel configuration


14


. Specifically, the overall length


20


is defined as the length between the center lines of the two switch locations


16


that are separated by the greatest distance in the length direction. For example, in the embodiment shown in

FIG. 2

, the overall length


20


of the key panel configuration


14


is the distance separating the center line of the left-most small switch location


16


″in the multi-switch location


16


′ and the center line of any of the right-most switch locations


16


, since those switch locations


16


are all substantially co-linear.




The overall width


22


of the key panel configuration


14


is defined as the length between the center lines of the two switch locations


16


that are separated by the greatest distance in the width direction. In the embodiment shown in

FIG. 2

, the overall width


22


of the key panel configuration


12


is the distance separating the center lines of any of the lower-most switch locations


16


, since they are all substantially co-linear, and the center lines of either of the upper-most switch locations


16


, since they are also substantially co-linear.




The strip of switch material


12


is best seen in FIG.


3


and may comprise an elongate, generally flexible member having a front side


21


and a back side


23


. The strip of switch material


12


may also be provided with a plurality of switches


24


which are operable from the front side


21


of the strip of switch material


12


. Generally speaking, and as will be discussed in greater detail below, each switch


24


provided on the strip of switch material


12


may be substantially identical to the others and may be located at substantially evenly spaced locations along the length of the strip of switch material


12


. However, other configurations are possible. For example, in the embodiment shown and described herein wherein the key pad configuration is provided with at least one multi-switch location


16


′, the strip of switch material


12


may be provided with a corresponding grouping


24


′ of individual switches


24


″, as best seen in

FIGS. 1 and 3

.




The arrangement of switches (e.g.,


24


,


24


″) on the strip of switch material


12


defines an aspect ratio for the strip of switch material


12


. As used herein, the aspect ratio of the strip of switch material


12


is the ratio of the overall length


26


to the overall width


28


. Expressed arithmetically, the aspect ratio of the strip of switch material


12


is the overall length


26


divided by the overall width


28


. The overall length


26


is defined as the distance separating the center lines of the two switches


24


that are located the greatest distance apart along the length direction, i.e., the distance between center lines of the two switches


24


that are located at opposite ends of the strip of switch material


12


. For example, in the embodiment shown in

FIG. 3

, the overall length


26


of the strip of switch material


12


is defined as that distance separating the center line of the left-most switch


24


and the center line of the right-most switch


24


.




The overall width


28


of the strip of switch material


12


is the distance separating the center lines of the two switches


24


that are located the greatest distance apart in the width direction. For example, in the embodiment illustrated in

FIG. 3

, the overall width


28


is the distance between the center line of the upper-most switch


24


″ and the center line of the lower-most switch


24


″ contained in the group of switches


24


′. Alternatively, if no grouping of switches


24


′ is provided, and the strip of switch material


12


comprises a single, substantially colinear row of switches


24


, then the width dimension


28


should be regarded as unity in order to avoid an indefinite aspect ratio when expressed arithmetically.




The relationship between the aspect ratios of the key panel configuration


14


and the strip of switch material


12


provides a convenient method for defining a part of the invention. That is, if the aspect ratio (expressed arithmetically) of the strip of switch material


12


is greater than the aspect ratio (expressed arithmetically) of the key panel configuration


14


, then the strip of switch material


12


may be regarded as being used in accordance with the teachings of the present invention. Stated another way, the strip of switch material


12


may be regarded as a one-dimensional array of switches


24


. Therefore, the use of the strip of switch material


12


in a key panel configuration


14


having a lower aspect ratio essentially amounts to a use of the one-dimensional array of switches


24


contained in the strip of switch material


12


to form a two-dimensional array of switches in the desired key panel assembly


10


. The aspect ratio measure is used to cover a situation, such as that illustrated in

FIGS. 1-3

, where one or more switch locations


16


in the key panel configuration


14


may comprise a group


16


′ of multiple switch locations


16


″. Absent the aspect ratio definitions provided herein, a strip of switch material


12


having a corresponding group


24


′ of switches


24


″ would not be properly regarded as a strictly one-dimensional array of switches.




Continuing now with the description, the strip of switch material


12


should include at least as many switches


24


as there are switch locations


16


in the key panel configuration


14


. If the strip of switch material


12


contains switches


24


in excess of the number of switch locations


16


, such additional switches


24


will simply remain unused in the final key panel assembly


10


. Referring back now to

FIG. 1

, the strip of switch material


12


may be provided with one or more folds


30


in order to arrange the various switches


24


,


24


″ provided on the strip of switch material


12


so that the switches


24


,


24


″ may be arranged to conform to the switch pattern


18


defined by the key panel configuration


14


.




For example, in the embodiment illustrated in

FIG. 1

, the strip of switch material


12


may be configured to conform to the key panel configuration


14


by first folding the vertical portion


37


of the strip of switch material


12


upwardly and then by folding it outwardly. The two folds


30


serve to reconfigure the switches


24


on the strip


12


so that they extend along a substantially horizontal portion


38


. The strip of switch material


12


is then folded twice again so as to reconfigure the remaining switches


24


on the strip


12


so that they extend along a substantially vertical portion


40


. After having been folded, the strip of switch material


12


may then be secured to a subpanel


42


(FIG.


4


), if desired, and connected to the electrical circuitry (not shown) associated with the device (also not shown). An optional bezel


32


(

FIG. 1

) may then be secured over the key panel assembly


10


, as will be discussed in greater detail below.




It should be noted that the radius (not shown) of each fold


30


should be greater than or equal to the minimum bend radius associated with the particular type of switch material that is used to form the strip of switch material


12


. So limiting the minimum radius of the various folds


30


will ensure reliable and long-lived operation of the key panel assembly


10


. Since the minimum bend radius of the switch material


12


will vary depending on the particular configuration and structural attributes of the switch material, as described in greater detail below, the present invention should not be regarded as limited to materials having any particular minimum bend radius.




The strip of switch material


12


may comprise any of a wide range of flexible, membrane-type switch devices that are well-known in the art and that are readily commercially available. For example, in one preferred embodiment, the strip of switch material


12


may comprise a flexible membrane switch assembly available from GM Nameplate, Intaq Electrotouch Systems, of Seattle, Wash. Alternatively, similar membrane type switches are available from Shin-Etsu Polymer of Union City, Calif. One configuration of such a membrane type switch will now be described in order to provide a better framework for understanding the invention.




Referring now to

FIG. 4

, one embodiment of the strip of switch material


12


may comprise a generally flexible, membrane type switch material comprising a generally flexible bottom membrane


44


having at least one switch contact


46


formed thereon. While a wide variety of switch contacts


46


are known for such devices, in one preferred embodiment switch contact


46


may be formed from first and second conductive elements


48


and


50


deposited on the bottom membrane


44


. The first and second conductive elements


48


and


50


may be electrically connected together to close the switch. A top membrane


52


having at least one dome


54


formed thereon may be positioned over the switch contact


46


so that an electrically conductive portion


56


of dome


54


will electrically connect together at least portions of the first and second conductive elements


48


and


50


when the dome


54


is depressed. The foregoing switch structure is generically referred to in the art as a “membrane switch,” although other terms are also used to describe this structure.




Depending on the particular membrane type switch configuration that is used, the top membrane


52


may be separated from the bottom membrane


44


by a spacer


58


. Spacer


58


defines an opening


60


therein that is aligned with the switch contact


46


and the dome


54


. Optionally, an overlay member


62


may be positioned over the top membrane


52


to protect the same from wear, foreign objects, and/or liquids. Overlay member


62


may be separated from the top membrane


52


by a spacer member


64


. Finally, and as mentioned above, the lower membrane


44


may be positioned adjacent a subpanel member


42


which provides support for the strip of switch material


12


. If necessary or desired in any particular application, the lower membrane


44


may be affixed to the subpanel member


42


by any of a wide range of adhesive materials that are readily commercially available for such purposes.




Depending on the requirements of the particular device in which the key panel assembly


10


is to be used, it may be required, or at least desirable, to configure the key panel


10


so that all of the switches


24


provided thereon are substantially co-planar. With reference now to

FIG. 5

, a second embodiment


110


of the key panel assembly illustrated in

FIG. 1

may be provided with a strip of switch material


112


having a plurality of additional folds


131


provided therein in order to position the switches


124


provided therein so that the switches


124


that are to be used are all substantially co-planar. In the example shown and described herein, the folds


131


are in addition to folds


130


which may be used to align the various switches


124


in the pattern (e.g., the pattern


18


shown in

FIG. 1

) defined by the particular key panel configuration (e.g., the key panel configuration


14


shown in FIG.


1


). As mentioned above, each fold


130


,


131


should have a radius (not shown) equal to or greater than the minimum bend radius associated with the particular switch material used.




Still other arrangements are possible. For example, with reference now to

FIG. 6

, a third embodiment


210


of a key pad assembly may comprise a strip of switch material


212


folded so that at least one switch


224


is located on the front side


221


of the strip of switch material


212


and so that at least one switch


224


′ is located on the back side


223


of the strip of switch material


212


. In the embodiment shown in

FIG. 6

, this configuration may be obtained by providing the strip of switch material


212


with two folds


230


as shown.




As mentioned above, the strip of switch material (e.g.,


12


,


112


,


212


) may comprise any of a wide range of flexible materials having switches provided thereon that may be folded in accordance with the present invention in order to form the key panel assembly (e.g.,


10


,


110


,


210


) of the present invention. For example, another embodiment


310


of a key panel assembly is shown in FIG.


7


and may comprise a strip of switch material


312


comprising a generally flexible bottom membrane


344


having at least one switch contact


346


provided thereon. Switch contact


346


may comprise first and second conductive elements


348


and


350


positioned in spaced-apart relation on the bottom membrane


344


. A top membrane


352


having a dome


354


provided thereon may be positioned over the bottom membrane


344


. The dome


354


may be provided with an electrically conductive region


356


thereon so that when dome


354


is depressed, the electrically conductive region


356


will electrically connect at least portions of the first and second conductive elements


348


and


350


, thus closing the switch


324


. The key panel assembly


310


may be provided with a key top


366


positioned over the dome


354


. A bezel


332


defining an opening


333


therein may also be provided to hold key top


366


in position. Finally, the bottom membrane


344


may be positioned adjacent a subpanel


342


which provides support for the strip of switch material


312


. Optionally, the bottom membrane


344


may be attached to the subpanel


342


by any suitable adhesive material.




It is contemplated that the inventive concepts herein described may be variously otherwise embodied and it is intended that the appended claims be construed to include alternative embodiments of the invention except insofar as limited by the prior art.



Claims
  • 1. A key panel, comprising:a key panel configuration having a number of switch locations arranged in a pattern so as to define an aspect ratio for said key panel configuration; and a strip of switch material having an aspect ratio that is greater than the aspect ratio of said key panel configuration, said strip of switch material also having a number of switches that is at least equal to the number of switch locations for said key panel configuration, said strip of switch material having at least one fold formed therein so as to arrange in the pattern the number of switches provided on said strip of switch material.
  • 2. The key panel of claim 1, further comprising a subpanel, said strip of switch material being positioned in contact with said subpanel, said subpanel providing support for said strip of switch material.
  • 3. The key panel of claim 2, wherein said strip of switch material is affixed to said subpanel.
  • 4. The key panel of claim 2, further comprising an overlay member positioned over said strip of switch material so that said strip of switch material is positioned between said overlay member and said subpanel.
  • 5. The key panel of claim 1, wherein said strip of switch material comprises:a bottom membrane having at least one switch contact thereon; and a top membrane having at least one dome formed thereon, said top membrane being positioned adjacent said bottom membrane so that said at least one dome formed on said top membrane is aligned with said at least one switch contact on said bottom membrane so that said at least one dome closes said at least one switch contact when said at least one dome is depressed.
  • 6. The key panel of claim 5, wherein said at least one switch contact provided on said bottom membrane comprises a first electrically conductive trace and a second electrically conductive trace, said first and second electrically conductive traces being positioned in spaced-apart relationship on said bottom membrane, and wherein said at least one dome formed on said top membrane comprises an electrically conductive portion, said electrically conductive portion on said at least one dome contacting at least portions of both said first and second electrically conductive traces on said bottom membrane when said at least one dome is depressed.
  • 7. The key panel of claim 5 further comprising a spacer defining at least one opening therein, said spacer being positioned between said bottom membrane and said top membrane so that said at least one opening in said spacer is aligned with said at least one switch contact provided on said bottom membrane.
  • 8. The key panel of claim 5, further comprising at least one key top positioned over said at least one dome formed on said top membrane, said at least one key top actuating said at least one switch contact provided on said bottom membrane when said key top is depressed.
  • 9. The key panel of claim 8, further comprising a bezel defining at least one opening therein sized to receive said at least one key top, said bezel being positioned over said top membrane member so that said at least one key top protrudes through said at least one opening provided in said bezel.
  • 10. The key panel of claim 1, wherein said strip of switch material comprises a front side and a back side, each of said switches provided in said strip of switch material being actuated from the front side of said strip of switch material.
  • 11. The key panel of claim 10, wherein said key panel configuration defines a front side and a back side and wherein said strip of switch material is folded so that at least one of said switches is located on the front side of said key panel configuration and so that at least one of said switches is located on the back side of said key panel configuration.
  • 12. The key panel of claim 1, wherein said strip of membrane type switch material comprises:a bottom membrane having at least one switch contact thereon; a spacer defining at least one opening therein, said spacer being positioned adjacent said bottom membrane so that said at least one opening in said spacer is aligned with said at least one switch contact provided on said bottom membrane; and a top membrane having at least one dome formed thereon, said top membrane being positioned adjacent said spacer so that said at least one dome formed on said top membrane is aligned with said at least one opening in said spacer so that said at least one dome closes said at least one switch contact when said at least one dome is depressed.
  • 13. The key panel of claim 12, further comprising an overlay member positioned over said top membrane.
  • 14. The key panel of claim 12, wherein said at least one switch contact provided on said bottom membrane comprises a first electrically conductive trace and a second electrically conductive trace, said first and second electrically conductive traces being positioned in spaced-apart relationship on said bottom membrane, and wherein said at least one dome formed on said top membrane includes an electrically conductive portion provided thereon, said electrically conductive portion on said at least one dome contacting portions of both said first and second electrically conductive traces on said bottom membrane when said at least one dome is depressed.
  • 15. A key panel, comprising:a key panel configuration having a number of switch locations arranged in a pattern so as to define an aspect ratio for said key panel configuration; and switch material strip means having an aspect ratio that is greater than the aspect ratio of said key panel configuration for providing switches at the switch locations and in the pattern defined by said key panel configuration.
  • 16. The key panel of claim 15, further comprising subpanel means positioned adjacent said switch material strip means for supporting said switch material strip means.
  • 17. The key panel of claim 15, further comprising overlay means positioned over said switch material strip means for protecting said switch material strip means.
  • 18. The key panel of claim 15, further comprising key top means positioned over said switch material strip means for actuating said switch material strip means.
  • 19. The key panel of claim 15, further comprising bezel means having an opening therein sized to receive said key top means, said bezel means positioned over said switch material strip means for holding said key top means adjacent said switch material strip means and for allowing said key top means to project through the opening in said bezel means.
  • 20. A method for fabricating a key panel, comprising:selecting a key panel configuration having a number of switch locations arranged in a pattern so as to define an aspect ratio for said key panel configuration; selecting a strip of switch material having an aspect ratio that is greater than the aspect ratio of said key panel configuration, said strip of switch material also having a number of switches that is at least equal to the number of switch locations for said key panel configuration; and folding said strip of switch material so as to arrange in the pattern the number of switches provided on said strip of switch material.
  • 21. A method for fabricating a key panel, comprising:selecting a key panel configuration having a number of switch locations arranged in a pattern so as to define an aspect ratio for said key panel configuration; fabricating a strip of switch material having an aspect ratio that is greater than the aspect ratio of said key panel configuration, said strip of switch material also having a number of switches that is at least equal to the number of switch locations for said key panel configuration; and folding said strip of switch material so as to arrange in the pattern the number of switches provided on said strip of switch material.
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Entry
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