Rotary and push type input device

Information

  • Patent Grant
  • 6809275
  • Patent Number
    6,809,275
  • Date Filed
    Monday, May 13, 2002
    22 years ago
  • Date Issued
    Tuesday, October 26, 2004
    20 years ago
Abstract
The disclosure describes a button wheel. The button wheel comprises a support frame including a pair of parallel opposed inner surfaces. A platform is nestably mounted in the support frame. The platform includes a pair of parallel opposed outer surfaces forming a pair of linear bearings with the parallel opposed inner surfaces of the support frame to allow the platform to translate from a biased rest position in a direction parallel to the opposed inner surfaces and the opposed outer surfaces. The button wheel also includes first and second spaced apart mounts fixed to one of the support frame and said platform. The button wheel includes a shaft disposed along an axis and including a first end rotatably engaged in the first mount and a second end rotatably engaged in the second mount. A wheel is mounted on the shaft and a rotation sensor is in operative communication with the wheel. The button wheel also includes a translation sensor coupled between the support frame and the platform.
Description




BACKGROUND




This application relates to an electronic device capable of sensing rotary and push-type user inputs.




The button-wheel is a device that can sense continuous rotation about a rotational axis as well as switch action in a direction perpendicular to the rotational axis; it increases user efficiency by enabling users to transmit two distinct types of input to a host machine while interacting with only one device.




Button-wheels are also related to knob-buttons that include rotational knobs that support a switching function perpendicular to the axis of rotation. These knob-buttons typically actuate switches through movement of knobs and knob mountings.




Button-wheels are currently prevalent in cursor control devices such as computer mice. Most conventional mouse button-wheels possess a configuration and switch actuation method similar to the one described in U.S. Pat. No. 5,912,661 to Siddiqui and illustrated in FIG.


1


. The button-wheel is built on a circuit board


28


that physically supports both mechanical and electrical components while placing button-wheel sensors in electrical communication with the rest of the mouse. The wheel


22


has a diameter that is much greater than its width. Wheel


22


is mounted on a relatively rigid shaft


64


that is much longer than wheel


22


's width. Shaft


64


is held in place by two bearings that allow shaft


64


to rotate about its axis, but not translate along this axis.




A first bearing


32


further constrains a first end


991


of shaft


64


from moving in the other two translational directions; however, first bearing


32


does not prevent shaft


64


from tilting about first bearing


32


. A second bearing is formed by two distinct components: a spring


58


that biases second end


992


and wheel


22


toward the user, and a slotted shape


34


that constrains second end


992


, such that it can translate only within the slot cutout. The slot cutout is a straight slot that is perpendicular to the axis of shaft


64


; this limits the motion of second end


992


to almost directly towards or away from circuit board


28


. Shaft


64


also has a collar-type feature


50


, located near slotted shape


34


, that hovers above a button


51


of switch


52


.




With this configuration, when the user pushes on wheel


22


, shaft


64


tilts about first bearing


32


and sweeps a wedge-shaped section of a circle. Shaft


64


compresses spring


58


, and collar


50


touches and depresses button


51


to actuate switch


52


. The magnitude of shaft


64


's tilt is limited by the length of the slot in slotted shape


34


, the full compression distance of spring


58


, and the actuation distance of button


51


. Spring


58


and button


51


together generate the desired user tactile and auditory feedback for this switch actuation action. Conductive paths along the circuit board


28


route the button signals to the mouse electronics (not shown).




Also on shaft


64


is an encoder disc


44


, which forms a complete optical rotary encoder with an optical emitter


46


and an optical detector


48


. Shaft


64


further contains a series of grooves that interact with a ratchet-like feature


42


to form a detent mechanism. When the user rotates wheel


22


, the encoder assembly (formed by encoder disc


44


, optical emitter


46


, and optical detector


48


) produces digital signals that are typically quadrature in nature. The detent mechanism (formed by grooves


40


and ratchet


42


) generates the desired user tactile and auditory feedback for the rotational motion. Conductive paths along the circuit board


28


route the encoder signals to the mouse electronics (not shown).




Variations on this general button-wheel idea are known in the art. The simplest variations involve using different types of the basic components (such as mechanical encoders instead of optical encoders, ball detents instead of grooves and ratchets, and lever-type switches instead of pushbutton switches) and shifting their relative location (such as moving switch


52


to the other side of slotted shape


34


or placing encoder disc


44


to the opposite side of first bearing


32


).




Slightly more complex variations involve combining many components into one integral unit. U.S. Pat. No. 6,188,393 to Shu, U.S. Pat. No. 6,157,369 to Merminod et al., and U.S. Pat. No. 6,014,130 to Yung-Chou describe devices in which the encoder disc (analogous to encoder disc


44


of the Siddiqui patent '661) is constructed as part of a wheel (analogous to wheel


22


of the Siddiqui patent '661). The devices outlined in U.S. Pat. No. 6,285,355 to Chang and U.S. Pat. No. 5,808,568 to Wu combines at least part of the detent mechanism with the encoder disc and the wheel (analogous to grooves


40


, ratchet


42


, encoder disc


44


, and wheel


20


of the Siddiqui patent '661) to generate one integral unit.




Other button-wheel variations involve different switch actuation actions. For example, U.S. Pat. No. 5,473,344 to Bacon et al. describes another tilting-shaft switch actuation method in which an additional slotted shape is utilized, and U.S. Pat. No. 5,446,481 to Gillick et al. discloses an hourglass-shaped wheel that tilts about its center to actuate switches located under either side of the hourglass-shaped wheel. These alternative tilting-shaft devices are more complex and require more components than the device presented in Siddiqui patent '661.




In addition to the tilting switch actuation action, alternatives that include semi-tilting switch actuation mechanisms also exist. Both U.S. Pat. No. 6,246,392 to Wu and U.S. Pat. No. 6,188,389 to Yen disclose button-wheels in which the two bearings supporting the wheel shaft include slotted shapes that have slots which help guide the motion of the wheel shaft; the devices disclosed in the Wu patent '392 and the Yen patent '389 bias the wheel shaft toward the user with one single spring located on one side of the wheel. The Merminod patent describes a different system that utilizes only one slotted shape; the end of the wheel opposite to the slotted shape is attached to a formed spring, and can move in a manner limited by the deflection of the spring. Since all three of the Wu patent '392, the Yen patent '389, and the Merminod patent '369 teach biasing the wheel toward the user on only one side of the wheel, a torque results when the user pushes on the wheel of any of these disclosed devices, and significant tilting of the wheel occurs. Thus, the action associated with these switch actuation inputs combines tilting as well as translation, and can be considered semi-tilting.




Minimally-tilting switch actuation mechanisms also exist. For example, U.S. Pat. No. 6,292,113 to Wu (Shown in FIG.


2


), U.S. Pat. No. 6,285,355 to Chang, U.S. Pat. No. 6,188,393 to Shu, U.S. Pat. No. 5,530,455 to Cillick et al., and older Microsoft® INTELLIMOUSE all disclose button-wheels in which the entire wheel mounting moves to achieve switch actuation. In order to enable the movement of the entire mounting, these devices tend to be larger, more complex, and more costly than the device of the Siddiqui reference. In the devices disclosed by the Wu patent '113, the Chang patent '355, and older INTELLIMOUSE, these wheel mountings are biased toward the user by one spring located on one side of the wheel. In contrast, in Gillick '455's and Shu '393's devices, the mountings are biased toward the user on both sides of the wheel. With biasing forces on both sides of the wheel, where user push-type forces are applied, the wheel mounting can respond to user push-type force with motion that is more translation than tilting. With this substantially translational motion, in which translation is the primary action of switch actuation, it is possible to produce tactile force and displacement responses that are more uniform across the width of the wheel. However, this additional biasing force usually increases the size, complexity, and cost of the mechanism beyond that associated with a single biasing force as will be explained later in the disclosure.




Despite these numerous button-wheel designs, the general tilting-shaft button-wheel idea and configuration described by Siddiqui is still currently the most popular commercial button-wheel embodiment. This is largely because button-wheels are mostly used in mice, and the Siddiqui device is a low-cost and low-complexity device that satisfies mouse design criteria.




Mice have minimal space constraints, since they must be at least a minimum external size for ergonomic reasons. This external size leads to internal spaces that are typically much larger than necessary to accommodate the sensors, structures, mechanisms, and electronics associated with conventional mouse features. Faced with this minimal space constraint, conventional mice have focused on minimizing cost and complexity instead of size. Thus, the internal components of mice are usually larger, cheaper, and easier to assemble than those found in more space-constrained input devices, such as PDA touch screens, laptop pointing sticks, and computer touchpads. This minimal space constraint has also affected the development focus of button-wheels in prior art devices. Siddiqui's device, along with the variations described above, focus on reducing the cost and complexity of the button-wheel, often at the trade-off of increased mechanism size.




Mice also have relatively minimal constraints on uniform displacement and force feedback to the user, which makes tilting and semi-tilting button-wheel devices viable devices. Tilting and semi-tilting systems provide varying displacement and force feedback across the width of the wheel; the wheel shaft acts as a lever arm about the center of tilt and scales the force and displacement feedback as dictated by geometry. However, since the width of the wheel is small compared to its lever arm, the differences in force and displacement tactile feedback along the width of the wheel are small and almost unnoticeable to the user. These minimal uniform feedback constraints have enabled mouse button-wheels to utilize simpler mounting designs and fewer components than if uniform feedback were required.




Unlike mouse button-wheels, many input devices must provide uniform force and displacement feedback. For example, some computer keyboards contained space bars that tilted about their centers. These space bars were unsatisfactory, since they were long enough such that the non-uniform feedback across the width of the space bar were noticeable to the user—some of these space bars even jammed when they were depressed on their left or right edges. In response, keyboard makers introduced a host of different linkages and mechanisms to ensure uniform feedback across the width of the space bar, and space bars that tilted about the center are no longer used.




Although the above observations have highlighted computer mice because button-wheels are most often found in mice, the same observations also apply to any device similar to mice in terms of size and feedback constraints. Examples of such devices include, but are not limited to, trackballs, handheld videogame control pads, and joysticks. However, these minimal constraints on size and feedback will not always apply. For example, as computer mice and similar devices grow in complexity to incorporate features such as wireless communications and force feedback, space constraints will grow tighter.




Existing devices such as Personal Digital Assistants (PDA) and laptops also have very tight—especially height to reduce the overall thickness of the PDA or laptop-space constraints. In addition, devices such as PDAs and laptops may best be served by button-wheels with wider wheels and lower ratios of wheel diameter to wheel width and shaft length to wheel width. These lower ratios help the button-wheels meet tighter space constraints and allow users to manipulate the button-wheels in more ways. Unlike button-wheels for mice, which are usually manipulated by one or two dedicated digits, button-wheels for PDAs and laptops may be located where users can access them with thumbs, multiple fingers, or either hand.




These lower ratios of wheel diameter to wheel width and shaft length to wheel width also mean tighter feedback requirements that make tilting and semi-tilting designs much less desirable. With these lower ratios, a tilting or semi-tilting design would yield a greater difference in force and displacement feedback along the width of the wheel than a similar design targeted for mice. This difference may be noticeable and disturbing to users. At an extreme case for a tilting shaft system, the user may not be able to actuate the button near the center of tilt, or may jam the button-wheel at the end opposite that of the center of tilt. These failure modes are similar to those of space bars that tilted about their centers, and accentuate the importance of uniform force and displacement response in button systems where the component that interacts with the user is relatively wide.




Button-wheels utilizing tilting or semi-tilting designs have a further disadvantage in that they usually need to accommodate a vertical travel height that is greater than that traveled by the wheel during switch actuation. The actual difference is dependent on the lengths of the lever arms from the center of pivot to the wheel and to the farthest pivoting or semi-pivoting point. For example, in a design with a tilting-shaft approach and a wheel mounted equidistant between two bearings, the vertical distance traveled by the section of the shaft within the bearing that does not function as the fulcrum is approximately twice that of the wheel. Mounting the wheel at the section of the shaft that travels the greatest distance during the tilting or semi-tilting switch actuation action (typically one of the end sections of the shaft) may reduce the motion that must be accommodated by the button-wheel during switch actuation. However, this approach also introduces undesirable characteristics associated with a cantilevered-wheel system.




The ideal button-wheel for this set of design criteria associated with applications similar to PDAs and laptops is one that minimizes size (especially height), ensures that no parts of the button-wheel need to travel more than the wheel during switch actuation, and provides uniform force and displacement feedback to the user during switch actuation. The ideal button-wheel also minimally increases the complexity and cost of the button-wheel.




Some prior-art devices do attempt to address some of the tighter space constraints, but they still utilize tilting as the main switch actuation mechanism. For example, U.S. Pat. No. 6,198,057 to Sato et al. (Shown in

FIG. 3

) and U.S. Pat. No. 6,194,673 to Sato et al. both shrink a tilting-shaft design by utilizing smaller parts and integrating multiple components into one mechanism; for example, the device of Sato '057 uses smaller mechanical and electrical components, removes the biasing spring and uses the switch as the biasing agent, replaces the optical wheel encoder with a mechanical one, and combines the mechanical encoder, detent, and bearing into one integral part.




Even though these two devices of Sato '057 and Sato '673 do shrink the size of the button-wheel noticeably, they do not address the shortcomings of a tilting or semi-tilting mechanism as outlined above. Both devices by Sato '057 and Sato '673 must be tall enough to accommodate the greater vertical distance traveled by the end of the shaft opposite from the center of tilt, which is greater than the actual vertical distance traveled by the wheel. In addition, these systems still have an inherently nonuniform tactile response across the width of the wheel.




Another button-wheel design that attempts to fit within the tighter space constraints is U.S. Pat. No. 6,211,474 to Takahashi. Takahashi's device is similar to the tilting-shaft design described by the Siddiqui patent'661with one exception. The wheel can tilt about the center of the wheel shaft as well as tilt about one of the bearings. Takahashi's device has the same deficiencies as both of the devices outlined by Sato '057 and Sato '673, and is more complex and even less uniform in tactile response to accommodate the additional degree of wheel tilt freedom about the center of the shaft.




A device that attempts to fit within the tight space constraints and does not use shaft tilt to actuate the button is U.S. Pat. No. 6,218,635 to Shigemoto et al. (Shown in FIG.


4


). Shigemoto '635 describes a mechanism in which the entire wheel mounting is located above a switch. When the user pushes on the wheel, the entire wheel mounting tilts about an external axis distinct from and parallel to the wheel axis to actuate the button of the switch. Although this configuration means that the button-wheel only has to accommodate the vertical travel of the wheel, having a moving mounting still results in a larger overall size and probably greater complexity than that associated with a stationary mounting and moving shaft. In addition, the Shigemoto device must also accommodate some horizontal motion of the mounting that is associated with the mounting tilt.




No button-wheel currently exists that fulfills all the design constraints associated with devices such as PDAs and laptops, where tight spaces and uniform tactile feedback are highly desirable. Existing devices hold onto ideas that are more applicable to computer mice, contain features that increase the size of the button-wheel, or introduce more complex and costly mechanisms. The present invention addresses the deficiencies of these prior art approaches.




SUMMARY




The disclosure describes a button wheel. The button wheel comprises a support frame including a pair of parallel opposed inner surfaces. A platform is nestably mounted in the support frame. The platform includes a pair of parallel opposed outer surfaces forming a pair of linear bearings with the parallel opposed inner surfaces of the support frame to allow the platform to translate from a biased rest position in a direction parallel to the opposed inner surfaces and the opposed outer surfaces. The button wheel also includes first and second spaced apart mounts fixed to one of the support frame and said platform. The button wheel includes a shaft disposed along an axis and including a first end rotatably engaged in the first mount and a second end rotatably engaged in the second mount. A wheel is mounted on the shaft and a rotation sensor is in operative communication with the wheel. The button wheel also includes a translation sensor coupled between the support frame and the platform.




The disclosure also describes an alternative embodiment of the button wheel. This embodiment comprises a support frame including a flat-spring region and a first mount disposed on the flat-spring region of the support frame. The button wheel includes a second mount spaced apart from the first mount and disposed on the support frame. A translation sensor is mounted in a fixed position with respect to the fixed region of the support frame. The button wheel also includes a shaft disposed along an axis and including a wheel mounted on the shaft and a first end rotatably engaged in the first mount and a second end rotatably and translatably engaged in the second mount so as to allow the shaft to translate with respect to the support frame in a direction substantially perpendicular to the axis to actuate the translation sensor upon the application of mechanical force to the wheel having a component substantially along the direction. The button wheel has a rotation sensor in operative communication with the wheel.




Another button wheel embodiment is described in the disclosure. The button wheel comprises a support frame and first and second spaced apart mounting members mounted to the support frame. A shaft is disposed along an axis and including a first end rotatably engaged in the first mounting member and a second end rotatably engaged in the second mounting member. A first translation limiter is disposed on the shaft proximate to the first end and adjacent to the first mounting member to limit the translation of the shaft along the axis. A second translation limiter is disposed on the shaft proximate to the second end and adjacent to the second mounting member to limit the translation of the shaft along the axis. A wheel is mounted on the shaft and a rotation sensor is in operative communication with the wheel. The button wheel includes a translation sensor coupled between the support frame and the shaft.




Another embodiment is described comprising a support frame and first and second biasing members mounted on the support frame. The button wheel includes first and second spaced apart movable mounting members mechanically coupled to the support frame through the first and the second biasing members. A shaft is disposed along an axis and includes a first end rotatably engaged in the first movable mounting member and a second end rotatably engaged in the second movable mounting member. A wheel is mounted on the shaft. A rotation sensor is in operative communication with the wheel and a translation sensor is coupled between the support frame and the shaft.











BRIEF DESCRIPTION OF THE DRAWINGS




Referring now to the figures, wherein like elements are numbered alike:





FIG. 1

is a partial cut-away view of a prior art button-wheel design for computer mice;





FIG. 2

is an isometric view of a prior art button-wheel design used in computer mice;





FIG. 3

is a partial cross-sectional view of another prior art button-wheel design that incorporates a tilting shaft to actuate a switch;





FIG. 4

is an isometric view of a prior art button-wheel design in which the platform tilts about an axis external to the wheel and parallel to the wheel axis to actuate a switch;





FIG. 5

is a cross-sectional view of an exemplary embodiment of a button-wheel that actuates a switch through translation of the platform;





FIG. 6

is a cross-sectional view of a button-wheel that actuates a switch through translation of the platform;





FIG. 7

is a cross-sectional view of an alternate embodiment for the bottom section of the exemplary embodiment depicted in

FIGS. 5 and 6

;





FIG. 8

is a cross-sectional view of an alternate embodiment for the bottom section of the exemplary embodiment depicted in

FIGS. 5 and 6

;





FIG. 9

is a cross-sectional view of an alternate embodiment for the bottom section of the exemplary embodiment depicted in

FIGS. 5 and 6

;





FIG. 10

is a cross-sectional view of an alternate embodiment for the bottom section of the exemplary embodiment depicted in

FIGS. 5 and 6

;





FIG. 11

is a cross-sectional view of an alternate embodiment for the bottom section of the exemplary embodiment depicted in

FIGS. 5 and 6

;





FIG. 12

is a cross-sectional view of an alternate embodiment for the bottom section of the exemplary embodiment depicted in

FIGS. 5 and 6

;





FIG. 13

is a cross-sectional view of a button-wheel embodiment in which the platform translates and the shaft physically contacts the switch to actuate the switch;





FIG. 14

is a cross-sectional view of a button-wheel embodiment in which the shaft translates independently from the platform to actuate the switch;





FIG. 15

is a side view that corresponds with

FIG. 14

;





FIG. 16

is a cross-sectional view of the button-wheel embodiment shown in

FIG. 14

in the configuration in which the switches are depressed;





FIG. 17

is a side view that corresponds with

FIG. 16

;





FIG. 18

depicts an alternate embodiment for the slotted shape that forms part of the mount that constrains the motion of the wheel shaft;





FIG. 19

depicts an alternate embodiment for the slotted shape that forms part of the mount that constrains the motion of the wheel shaft;





FIG. 20

depicts an alternate embodiment for the slotted shape that forms part of the mount that constrains the motion of the wheel shaft;





FIG. 21

is a cross-sectional view of a button-wheel embodiment in which a movable mount supported by a coiled spring enables one end of the wheel shaft to translate independently from the other end of the shaft;





FIG. 22

is a side view that corresponds with

FIG. 21

;





FIG. 23

is a cross-sectional view of a button-wheel embodiment in which a movable mount is supported by a flat spring;





FIG. 24

is a side view that corresponds with

FIG. 23

;





FIG. 25

is a cross-sectional view of a button-wheel embodiment in which two movable mounts are supported by flat springs;





FIG. 26

is a cross-sectional view of a button-wheel embodiment utilizing a non-contact switch in which two movable mounts are supported by flat springs;





FIG. 27

is a top view of a button-wheel design in which a movable mount is supported by a cutout of the platform


3


;





FIG. 28

is a cross-sectional view of the button-wheel embodiment depicted in

FIG. 27

;





FIG. 29

is a side view that corresponds with

FIG. 28

;





FIG. 30

is a cross-sectional view of the button-wheel design depicted in

FIG. 27

in which the switch is depressed;





FIG. 31

is a side view that corresponds with

FIG. 30

;





FIG. 32

is another side view that corresponds with

FIG. 28

;





FIG. 33

is another side view that corresponds with

FIG. 31

;





FIG. 34

is a partial top-view of an alternative cutout for the flexible, biasing member supporting the movable mount shown in

FIGS. 27 through 33

;





FIG. 35

is a partial cross-sectional view that depicts a feature that can be added to the wheel shaft to reduce undesirable tilting of the shaft during switch actuation;





FIG. 36

is a side view that depicts an additional shaft mount that reduces undesirable tilting of the shaft during switch actuation;





FIG. 37

is a partial cross-sectional view that corresponds with

FIG. 36

;





FIG. 38

depicts an alternate embodiment for the additional mount depicted in

FIGS. 36 and 37

;





FIG. 39

depicts an alternate embodiment for the additional mount depicted in

FIGS. 36 and 37

;





FIG. 40

depicts an alternate embodiment for the additional mount depicted in

FIGS. 36 and 37

; and





FIG. 41

is a partial cross-sectional view of an additional support that reduces undesirable tilting of the shaft during switch actuation.











DETAILED DESCRIPTION




Those of ordinary skill in the art will realize that the following description of the present invention is illustrative only and not in any way limiting. Other embodiments of the invention will readily suggest themselves to such skilled persons.





FIGS. 5 through 13

outline a preferred embodiment in which biasing members interact with the platform (either by direct physical contact or through other components that support the platform) to bias the platform, shaft, and wheel and ensure substantial translation of these three components and uniform tactile feedback along the width of the wheel in response to push-type force on the wheel along the direction indicated by F. Substantial translation is translation that is substantially parallel to the direction F and having a minimal tilt or deviation from the direction F. This preferred embodiment can utilize any type of rotary encoder that is commercially available as a first sensor, or simply a rotation sensor


102


that senses the rotation of the wheel, and a second sensor, or simply a translation sensor that senses the translation of the wheel created by user push-type forces on the wheel along the direction F. Similarly, if tactile feedback in response to rotation of the wheel is desired, this preferred embodiment can utilize any type of tactile feedback mechanism similar to those found in commercially available button-wheels. One example is to employ a component that combines a mount, a rotary encoder, and a detent mechanism into one unit that reduces or limits shaft tilt.




Referring to

FIG. 5

, a cross-sectional view of an exemplary embodiment of a button-wheel


200


is illustrated. The button-wheel


200


includes a wheel


202


having a generally cylindrical shape in which the width dimension is larger than the diameter dimension. It is contemplated that variations of dimensions and shape of wheel


202


are within the scope of the disclosure. The button-wheel


200


includes a shaft


204


. The shaft


204


can be an axial extension of the wheel


202


wherein the shaft


204


has a smaller diameter than that of the wheel


202


. The shaft


204


and wheel


202


can also have the same diameter, such that the wheel


202


is simply a defined region of the shaft


204


. Wheel


202


is supportable by at least one mount or in a preferred embodiment, two mounts, a first mount


206


and a second mount


208


. The first mount


206


and the second mount


208


provide rotational and translational support for wheel


202


through shaft


204


. Any combination of mount types is contemplated as part of this disclosure.




The first mount


206


and second mount


208


are mounted to a platform


210


. Platform


210


can be a structure that provides a substantially rigid surface to attach the first mount


206


and the second mount


208


, as well as minimize shaft


204


binding with first mount


206


and second mount


208


, due to platform deflection relative to shaft


204


. Additionally, platform


210


can provide sufficient stiffness such that translational forces applied to wheel


202


can be transmitted from wheel


202


through shaft


204


into first mount


206


and second mount


208


, and into platform


210


. Platform


210


includes at least a first outer surface


212


. In another embodiment, platform


210


includes two opposed outer surfaces, a first outer surface


212


and a second outer surface


214


. The first outer surface


212


and second outer surface


214


are located at opposite ends of the platform


210


. The first outer surface


212


and second outer surface


214


are located substantially parallel to and on opposite sides of the platform


210


.




Further included with the button-wheel


200


is a support frame


216


. The support frame


216


includes multiple surfaces that enclose and support the platform


210


. The support frame


216


includes a base


218


and at least two sides, a first side


220


having a first inner surface


222


and a second side


224


having a second inner surface


226


. The sides


220


and


224


protrude from the base


218


substantially perpendicular to a planar base surface


228


formed by the base


218


. The sides


220


and


224


are affixed on opposite ends of the base


218


. The first outer surface


212


and the second outer surface


214


of the platform


210


are located within the button-wheel


200


such that the first inner surface


222


and the second inner surface


226


guide the first outer surface


212


and the second outer surface


214


. Located between the base


218


and the platform


210


is one type of translation sensor in the form of a push button switch


230


. The switch


230


includes a button


232


disposed on the switch


230


. The switch


230


includes a biasing member


234


that biases the button


232


and in some embodiments the platform


210


and associated button-wheel components and subcomponents. Also included within the button


232


is a button sensor


236


. The operational relationship of the components and subcomponents of the button-wheel


200


can be further explained below.





FIG. 5

depicts an embodiment of a button-wheel


200


in which the switch


230


combines the functions of sensing translation and biasing, via the button sensor


236


that senses user push-type inputs on the wheel


202


and the biasing member


234


, respectively. Switch


230


, shown in one of many embodiments as a pushbutton switch, having the button


232


and biasing member


234


that can produce spring-like reaction forces in response to translation of the platform


210


along a direction F indicated by the force direction arrow


238


. When a user of the button-wheel applies a push-type force on the wheel


202


along the direction shown by F


238


, this user force is transmitted through the shaft


204


to the first mount


206


and second mount


208


. Mounts


206


and


208


are designed to minimize the tilting of shaft


204


, and transmit the user force toward the platform


210


. Motion of platform


210


is guided by the sides


220


and


224


of the support frame


216


to translate along the direction shown by direction arrow


238


. The push-type force on wheel


202


causes platform


210


to substantially translate along the direction shown by direction arrow


238


, with minimal tilt or deviation therefrom towards the base


218


of support frame


216


. Platform


210


normally rests on or near button


232


. A downward motion of platform


210


depresses button


232


and actuates switch


230


. The button-wheel configuration shown in

FIG. 5

thus biases and guides platform


210


such that translation is the primary action associated with switch actuation. Button


232


and biasing member


234


provide the tactile displacement and force feedback associated with switch actuation, and limit the total possible travel of wheel


202


by limiting the total possible travel of platform


210


. Additional features or components that function as biasing members or hard stops can be added to the button-wheel


200


shown in

FIG. 5

to further refine the feel and limit of the travel associated with switch actuation.




The components of the current embodiment can be located and oriented in alternative configurations as shown in

FIG. 6

, to lower cost and complexity of the button-wheel device. For example, in an embodiment in which platform


210


is a circuit board with conductive traces


240


that facilitate the acquisition and transmission of button-wheel signals, switch


230


can be mounted on the side of platform


210


opposite from wheel


202


. The button


232


is adjacent and in contact with planar base surface


228


. When the user applies push-type force on wheel


202


along the direction shown by direction arrow


238


, platform


210


substantially translates toward support frame


216


and depresses button


232


of switch


230


against base


218


and actuates switch


230


. Such a configuration, which is shown in

FIG. 6

, enables the designer to place switch


230


in direct electrical communication with the conductive traces


240


through surface mount technology, via technology, through-hole technology, or other means if necessary while incurring only negligible changes in the button actuation process or feel. User rotational inputs to wheel


202


can be accomplished without creating substantial translation of platform


210


.




In the embodiment of the button-wheel


200


shown in

FIGS. 5 and 6

, the outer surfaces


212


and


214


of platform


210


and first inner surface


222


and second inner surface


226


of support frame


216


function as linear bearings. Thus, the tolerances between the first outer surface


212


and first inner surface


222


and the second outer surface


214


and second inner surface


226


are preferably tightly controlled to minimize chances of binding and sticking and to ensure uniform tactile feedback. Maintaining uniform feedback means that similar displacement and force feedback are produced regardless of where along the width of wheel


202


the user applies push-type force along the direction shown by direction arrow


238


. Those skilled in the art will note that if button


232


has a larger area of contact with platform


210


, or if outer surfaces


212


and


214


are increased in size to improve alignment precision and to facilitate the interaction between mounting


210


and support frame


216


, then the tolerances between outer surfaces


212


and


214


and inner surfaces


222


and


226


can be made greater.





FIGS. 7 through 13

depict alternative embodiments for the components and features of the button-wheel


200


that are located as depicted below platform


210


, including platform


210


. Components and features of the button-wheel


200


depicted above platform


210


, such as wheel


202


, remain unchanged as depicted in FIG.


5


and thus are not explicitly shown in

FIGS. 7

to


13


.





FIG. 7

illustrates an embodiment of button-wheel


300


where platform


210


is supported by multiple switches, switch


302


, switch


304


, and switch


306


, each switch having buttons. Switch


302


having button


308


, switch


304


having button


310


, and switch


306


having button


312


. Each switch and button also has a biasing member and sensor (not shown). The biasing members can provide spring-like reaction forces in response to platform


210


translation along the direction shown by direction arrow


238


. Switches


302


,


304


, and


306


are selected and located such that, when the user applies push-type force on wheel


202


(not shown) along the direction shown by direction arrow


238


, platform


210


substantially translates and pushes buttons


308


,


310


, and


312


and actuate switches


302


,


304


, and


306


. Those skilled in the art will note that, if biasing members associated with switches


302


,


304


, and


306


provide similar force and displacement reaction in response to translation of platform


210


along the direction shown by direction arrow


238


, locating them symmetrically about the expected center of user push-type force application locations and close to inner surfaces


202


and


212


helps to ensure that platform


210


will substantially translate along the direction shown by direction arrow


238


. The location will also ensure that platform


210


will minimally deviate from the direction F (tilt), in response to push-type force along the direction shown by direction arrow


238


even when such user push-type force is applied near a portion of wheel


202


closer to switch


302


, and farther from switch


304


, or switch


306


. These multiple locations of support help ensure substantial translation also make it possible for the tolerances between outer surfaces


212


and


214


of FIG.


5


and inner surfaces


222


and


226


to be greater than required by the configurations shown in

FIGS. 5 and 6

.




In another embodiment, only one of the switches


302


,


304


, and


306


has to be powered and connected to the button-wheel electronics (not shown) to achieve ON/OFF switch functionality. Any of the other two switches, if also powered and in electrical communication with the button-wheel electronics, can serve as a backup switch. If the other two switches are not powered and are not in electrical communication with the button-wheel electronics, then they can be dummy switches that function only as biasing members that help ensure substantial translation and provide uniform tactile feedback.




To help ensure substantial translation and uniform tactile feedback for the simple embodiment shown in

FIG. 8

, compressive biasing members


314


are shown substituted for the switches


302


and


306


mountable between the platform


210


and the base


218


on the planar base surface


228


. The biasing members


314


can produce spring-like reaction forces similar to that of the switch


304


. The biasing members


314


may consist of any component and material able to produce spring-like responses in response to push-type inputs transmitted through the platform


210


, (for example, unpowered switches, coils, snap domes, compression springs, extension springs, torsion springs, flat springs and elastomeric bumps).





FIG. 9

shows another embodiment including tensile biasing members


316


in which the tensile biasing members


316


are mountable to the platform


210


at ends near the first side


220


and the second side


224


of the base


218


. A switch


318


is mountable between the platform


210


and the base


218


on planar base surface


228


. In an embodiment the switch


318


is one pushbutton switch. This embodiment allows limited translation of the platform


210


in the directions indicated by G and the bi-directional arrow


320


, which may be desirable in some button-wheel designs. Those skilled in the art will note that, to ensure substantial translation of platform


210


along the direction shown by direction arrow


238


in response to user input forces along the direction shown by direction arrow


238


in the configuration shown in

FIG. 9

, biasing members


316


may need to be biasing members that generate spring-type reactions different from switch


318


in response to the same input force vector.





FIG. 10

shows another embodiment that utilizes a breakbeam sensor


322


for second sensor


104


. The breakbeam sensor


322


is a second sensor variation that utilizes an alternate technology that does not also function as a biasing member. The breakbeam sensor


322


, which is an optical beam-breaking type sensor formed from a photo-emitter


324


and photo-detector


326


fixed to the base


218


, is non-contact and does not provide any spring-type reaction forces. During operation of the breakbeam sensor


322


, emitter


324


transmits photons that are sensed by detector


326


, and they function together to determine the presence or non-presence of a blocking piece


328


extending from platform


210


. Blocking piece


328


can be designed such that the length that extends beyond the platform


210


is short enough to allow detector


326


to detect photons emitted by emitter


324


when the platform


210


is in a normally non-translated position. When the user pushes with a force along the direction shown by direction arrow


238


, the movement of platform


210


causes blocking piece


328


to interpose between detector


326


and emitter


324


; this prevents detector


326


from sensing the photons from emitter


324


, and results in a change in the state of the detector signals that indicates switch actuation. Two biasing members


330


and


332


which support platform


210


are preferably similar in spring response and placed in a geometrically symmetrical manner to help ensure substantial translation of platform


210


and uniform tactile and displacement feedback in response to user push-inputs on wheel


202


along the direction shown by direction arrow


238


.




It is also within the scope of this disclosure to design blocking piece


328


to normally obstruct emitter


324


and detector


326


, and move into a non-blocking state with sufficient user input force along the direction shown by direction arrow


238


. This latter approach may be best accomplished by incorporating a passage


334


or cutout in blocking piece


328


. The passage


334


or cutout can be placed close to platform


210


such that blocking piece


328


obstructs communication between photo emitter


324


and photo detector


326


when there is no translation of the platform


210


along the direction shown by direction arrow


238


. Then, with sufficient user input force along the direction shown by direction arrow


238


, the substantial translation of platform


210


brings the passage


334


into place between emitter


324


and detector


326


such that blocking piece


328


no longer prevents detector


326


from sensing the photons of emitter


324


. Those skilled in the art will also note that a passage or cutout in blocking piece


328


can also be used in the embodiment where blocking piece


328


normally does not obstruct emitter


324


and detector


326


. In this embodiment, the passage


334


can be located such that the photo emitter


324


and detector


326


can optically communicate when there is no translation of the platform


210


along the direction shown by direction arrow


238


. Sufficient user input force along the direction shown by direction arrow


238


translates platform


210


and removes passage


334


from alignment between emitter


324


and detector


326


such that optical communication is broken between emitter


324


and detector


326


. The translated platform


210


places the passage


334


into a position such that blocking piece


328


prevents detector


326


from sensing the signals of emitter


324


. User rotational inputs to wheel


202


can be accomplished without creating substantial translation of platform


210


.




Although the embodiment depicted in

FIG. 10

explicitly calls out a beam-breaking type sensor as the alternative switching technology used, other switching technologies can also be incorporated into the button-wheel


300


. For example,

FIG. 11

illustrates a proximity sensor


336


utilized as a translation sensor for another embodiment of the button-wheel


300


. The proximity sensor


336


can include a first sensor member


338


and a second sensor member


340


. The first sensor member


338


can be fixed to platform


210


and located opposite from second sensor member


340


, which is fixed to planar base surface


228


of base


218


. The proximity sensor


336


senses the movement of platform


210


relative to base


218


, in response to user push-type inputs on wheel


202


(not shown) along the direction shown by direction arrow


238


. A thresholding algorithm can be used in conjunction with the outputs of the proximity sensor


336


to generate appropriate switching signals.





FIG. 12

shows strain gauges


342


,


344


, and


346


as another potential technology for another embodiment of the second sensor.

FIG. 12

shows an embodiment in which three second sensors are formed by strain gauges


342


,


344


, and


346


. The strain gauge


342


is disposed on biasing member


348


that is mounted to base


218


. The strain gauge


344


is disposed on biasing member


350


that is mounted to base


218


. The strain gauge


346


is disposed on biasing member


352


that is mounted to base


218


. The biasing members


348


,


350


and


352


can, for example, be flat springs that deform and deflect in reaction to forces from platform


210


. Biasing members


348


,


350


and


352


extend from base


218


and support platform


210


. These biasing members


348


,


350


and


352


are preferably designed and located to help ensure substantial translation of platform


210


in response to user push-type inputs on wheel


202


(not shown) along the direction shown by direction arrow


238


. When push-type inputs are applied, platform


210


compresses biasing members


348


,


350


, and


352


such that strain gauges


342


,


344


, and


346


change in resistance. This change in resistance can be sensed and used to provide the signals associated with switch actuation of the button-wheel


300


. In an alternate embodiment, strain gauges


342


,


344


, and


346


are embedded within biasing members


346


,


350


, and


352


, respectively. In an alternate embodiment, only one or two of the strain gauges


342


,


344


, and


346


and associated biasing member


348


,


350


, and


352


respectively are used by button-wheel


300


. In an alternate embodiment, additional biasing members comprise button-wheel


300


. Although

FIGS. 10

,


11


and


12


depict only three potential alternatives to conventional switches that can be used for the second sensor, those skilled in the art will note that many other alternative technologies, such as load cells, are viable and are contemplated as part of this disclosure.





FIG. 13

is a cross-sectional view that depicts another embodiment of button-wheel


400


in which an aperture


402


in platform


210


enables a switch


404


to interact with shaft


204


instead of platform


210


. In embodiments when switch


404


utilizes a technology that can provide spring-like response to push-type inputs applied by the user along the direction shown by direction arrow


238


, then switch


404


may be a biasing member that interacts with shaft


204


that can be taken into account when selecting biasing members for button-wheel


400


. The required height of the button-wheel


400


is reduced, since the dimension of gap


406


between the platform


210


and base


218


now has to accommodate only the maximally compressed biasing members


408


and


410


, and not a maximally compressed switch


404


. Since biasing members


408


and


410


do not require the electronics associated with switches and do not have to adopt the tubular compression/extension spring configuration as shown in

FIG. 13

, it is possible to include biasing members that occupy smaller dimensions than maximally compressed switches. Similar to the alternative biasing member and second sensor embodiments shown in

FIGS. 8

to


13


, although

FIG. 13

shows one standard pushbutton switch


404


and the biasing members


408


and


410


as two standard extension/compression springs attached between platform


210


and base


218


, alternative sensors and biasing member types and biasing member locations are possible.




The total possible translation in the direction shown by direction arrow


238


for wheel


202


as shown in the embodiments of

FIGS. 5 through 13

can be defined by the maximum button depression of the associated switches and the maximum compression of the associated springs, or hard stops formed by other associated button-wheel features (such as blocking piece


328


). It is also contemplated that additional features or components can be included to further define the maximum translation possible for wheel


202


.




It is also within the scope of this preferred embodiment to utilize second sensors capable of indicating multiple levels (extent) of user push-type inputs. For example, the various pushbutton switches shown in

FIGS. 5 through 9

can be pushbutton switches with at least two positions of switch actuation such that they can indicate at least three levels of compression, and thus at least three levels of translation of platform


210


. The additional information relating to the level of translation of platform


210


may be useful in some input devices by enabling one level of translation and associated position of switch actuation to trigger one action while additional levels of translation and associated positions of switch actuation trigger alternative actions.




Multiple levels of translation can also be provided by many of the alternative technologies possible for the second sensor. For example, for the breakbeam sensor


322


shown in

FIG. 10

, blocking piece


328


can be designed such that a pattern of passages instead of a single passage is present in blocking piece


328


such that different levels of platform


210


translation results in different levels of light blockage from emitter


324


to detector


326


. For the proximity sensor


336


shown in

FIG. 11

, standard proximity sensor technology, such as capacitive or hall effect sensors, produce an analog signal dependent on the separation between the first sensor member


338


and the second sensor member


340


and can sense a continuum of separation between the first sensor member


338


and the second sensor member


340


. The strain gauges


342


,


344


, and


346


shown in

FIG. 12

can also sense a continuum of deflection of the associated biasing members. These signals from the proximity sensor and the strain gauges can be used to estimate the displacement of platform


210


from some reference and the level of translation of platform


210


; the resulting estimate of displacement or translation and can even be differentiated over time to estimate the velocity and acceleration of platform


210


.




The configuration of second sensors and biasing members shown in

FIGS. 7 through 13

are preferably designed to ensure substantial translation of platform


210


in response to user push-type force along the direction shown by direction arrow


238


on wheel


202


regardless of the exact location of user push inputs on wheel


202


. In most cases of substantial translation, some limited tilting (deviation from the direction shown by direction arrow


238


) of platform


210


may still occur even though translation is still the primary action associated with switch actuation. In the case that a set of second sensors is used, and the second sensors have very high sensitivity to the motion of platform


210


, then this limited tilting may be utilized to provide greater user control of the host device through the button-wheel (


200


,


300


,


400


).




For example, for the embodiment shown in

FIG. 12

, if the strain gauges


342


,


344


and


346


are well characterized and the spring constants of the biasing members


348


,


350


and


352


are known, then the signals from the strain gauges can be used to calculate the reaction forces provided by the different biasing members. If it is possible to further assume that the user force along the direction shown by direction arrow


238


dominates, and if the biasing members containing second sensors define a complete statically determinant situation associated with platform


210


, then force equilibrium considerations are sufficient for estimating the location of user force input and user force magnitude. Alternatively, if the biasing members containing second sensors define a complete statically indeterminate situation, then additional geometric and material considerations may be necessary to estimate the location of user force input and user force magnitude.




However, since this estimate of user force input location is more accurate when the biasing members deflect in different ways, when platform


210


tilts to some limited extent, and when platform


210


only applies forces that can be neglected in the above calculations on components of the button-wheel other than the biasing members that contain second sensors, careful selection and placement of button-wheel components is required to ensure substantial translation of platform


210


and wheel


202


in response to user push-type inputs on wheel


202


along the direction shown by direction arrow


238


, and to ensure that the magnitude of tilting is acceptable. Button-wheels that can estimate the effective magnitude and application point of the user input force enable finer user control, and are useful in some applications. Example applications include, and are not limited to, menu selection, horizontal or vertical scrolling, and game control.




The approach used with the strain gauges to estimate user force location can also be used when other switching technologies that can sense a continuum of translation levels are used. For example, load cells are ready alternatives. However, some second sensor technologies are not sufficiently sensitive to the motion of platform


210


and may require tilting of platform


210


of such a magnitude that substantial translation of platform


210


no longer occurs during switch actuation. Significant tilting is undesirable, and the use of second sensor technologies that require significant tilting of wheel


202


and platform


210


in estimating user input force locations are preferably avoided. One method of overcoming this limitation is to utilize second sensors of different technologies in the same button-wheel device; a type of second sensor can be used to generate switch actuation signals (which may be involve multiple levels of translation and positions of switch actuation) while another type of second sensor can be used to calculate reaction forces and estimate the location of user push inputs on wheel


202


.




Although

FIGS. 5 and 6

depict button-wheel embodiments that use only one switch that combines a second sensor with a biasing member and

FIGS. 7 through 13

depict embodiments that use a total of three components that function as biasing members and/or second sensors, many other alternative configurations with different numbers and arrangements of the second sensors and biasing members are viable in ensuring substantial translation of platform


210


in response to user push-type inputs on wheel


202


along the direction shown by direction arrow


238


, and in promoting a uniform tactile and displacement response to said user inputs. The actual number and placement of the second sensors and biasing members depend on whether or not combination second sensors and biasing members are used, and the size, shape, and material of platform


210


. For example, if the region of platform


210


that supports the button-wheel


200


,


300


,


400


has a relatively rectilinear shape, then a total of four biasing members placed near the corners of this region may be preferred; if none of the biasing members are part of a component that also functions as a second sensor, then some type of second sensor that produces reaction forces that are negligible when compared to the biasing members may be placed anywhere on platform


210


where it is possible to properly sense user push-type inputs. It is also possible to utilize greater numbers of biasing members to complement a rectilinear region of platform


210


. For example, five biasing members can be distributed with one at the center of the rectilinear region and the other four at the corners.




Additional biasing members incur extra cost, and are useful only when the relatively square region is sufficiently large to require the extra support points to reduce undesirable tilting of the shaft and ensure substantial translation during switch actuation. In the case that the region of platform


210


that supports the button-wheel


200


,


300


, or


400


is elongated and is more oblong in shape, only a total of two biasing members may be necessary. For this more oblong shape, one biasing member can be located underneath the shaft on one side of the wheel while the other can be located underneath the shaft on the other side of the wheel. Similar to the rectilinear case described above, if none of the biasing members are part of components that also function as second sensors, then some type of second sensor that produces reaction forces that are negligible when compared to the biasing members may be placed anywhere on platform


210


where it is possible to properly sense user push-type inputs.




The button-wheel components can be located and oriented in alternative configurations to lower the cost and complexity of the final device. For example, if platform


210


is a circuit board with conductive traces to facilitate the acquisition and transmission of button-wheel signals, then the switch (or switches) of the button-wheel can be mounted on the side of platform


210


opposite from wheel


202


and placed in direct electrical communication with the circuit board traces (through standard surface mount technology, via technology, through-hole technology, or other means if necessary). With this configuration, when the user applies push-type force on wheel


202


along the direction shown by direction arrow


238


, platform


210


substantially translates toward support frame


216


and depresses the button(s) of the switch(es) against the support frame


216


and switch actuation occurs. The resulting switch actuation will be almost identical from the user's perspective to the embodiment where the switch(es) is(are) mounted on support frame


216


.




Additional variations of this embodiment are viable and still retain equivalence to the invention described within this document. Such variations include, but are not limited to, the following. The exact component technologies and types can change; for example, the wheel encoder can be optical or mechanical. The component sizes and shapes can also vary; for example, the wheel can be disc-like, cylindrical, spherical, have circular cross-section, have polygonal cross section, or have variable cross-sectional shape across the width of the wheel; or, the shaft may also vary in cross-section, and contain stepped or rounded features as necessary to achieve its functions and to simplify button-wheel construction.




Other button-wheel embodiment may also utilize components that perform the function of many parts of the button-wheel; examples of components that can easily combined into contiguous units include, but are not limited to: at least part of a first mount and at least part of a mount supporting wheel shaft


204


, at least part of wheel


202


and at least part of any rotary tactile feedback mechanisms, and at least part of wheel


202


and at least part of wheel shaft


204


. In fact, wheel


202


can be as simple as an elastomeric material covering directly molded onto wheel shaft


204


, or a region of wheel shaft


204


can be denoted wheel


202


such that wheel


202


is integral to wheel shaft


204


. The button-wheel may also utilize parts fashioned from many distinct components; for example, a first sensor can comprise of a breakbeam sensor formed from a photoemitter, an encoder disc that rotates in response to rotation of wheel


202


, and a photodetector.




The embodiments can also utilize component mounting methods and mounting locations different from those described in

FIGS. 5 through 13

; for example, the biasing members and second sensors (translation sensors) can be mounted on platform


210


or support frame


216


and can be oriented in a variety of ways as long as they still ensure substantial translation of platform


210


along the direction shown by direction arrow


238


, properly sense translation of platform


210


along the direction shown by direction arrow


238


, and provide uniform tactile force and displacement feedback parallel to the direction shown by direction arrow


238


in response to push-type forces on wheel


202


along the direction shown by direction arrow


238


.





FIGS. 14 through 17

and


21


through


34


depict another embodiment in which members support the shaft, in preferred embodiments biasing members bias the wheel shaft (either by direct physical contact or through bearings and other components that support the wheel shaft) to ensure substantial translation of the wheel shaft and wheel and uniform tactile feedback along the width of the wheel in response-to push-type force on the wheel along the direction shown by direction arrow


238


. In some embodiments, at least one mount that supports the shaft is composed of more than one distinct component or element, such as a slotted shape functioning in conjunction with a biasing member. As shown in

FIG. 14

(an embodiment of button-wheel


500


), the shaft


204


has a first end


502


that can translate independently from a second end


504


located opposite thereof. The first end


502


can move with a vector component along the direction shown by direction arrow


238


while second end


504


does not move or moves with a vector component opposite the direction shown by direction arrow


238


. However, shaft


204


is carefully biased toward the user by biasing members such that ends


502


and


504


largely translate together along the direction shown by direction arrow


238


. Thus, when the user applies push-type force on wheel


202


, wheel shaft


204


substantially translates independently from platform


210


and actuates at least one second sensor. To ensure substantial translation of shaft


204


along the direction shown by direction arrow


238


and improve the uniformity of tactile force and displacement feedback in response to push-type inputs along the direction shown by direction arrow


238


, additional features and components may be used to further guide and constrain shaft


204


.





FIGS. 14 through 17

illustrate embodiments in which shaft


204


is supported by two switches


506


and


508


that function as both biasing members and second sensors (translation sensors). Switches


506


and


508


are shown as pushbutton switches in

FIGS. 14 through 17

, but they can be of any type of translation sensor that can also provide spring-like reaction force in response to translation of shaft


204


along the direction shown by direction arrow


238


.

FIG. 14

is a cross-sectional view depicting the situation in which switches


506


and


508


are not actuated, and

FIG. 15

is the corresponding side view.

FIG. 16

is a cross-sectional view depicting the situation in which the switches


506


and


508


are actuated, and

FIG. 17

is the corresponding side view.

FIGS. 14 through 17

do not explicitly show the first sensor that senses rotation of wheel


202


or, if included, the tactile feedback mechanism that provides tactile feedback in response to rotation of wheel


202


. Any first sensors or rotational tactile feedback mechanisms can be located anywhere within the button wheel


500


as long as they do not interfere with the rotation or substantial translation of the button wheel


500


, and properly sense rotation or provide feedback. These parts of the button-wheel can also utilize any of the designs disclosed in commercially available devices.




The two switches


506


and


508


are selected and located to bias wheel shaft


204


such that substantial translation of wheel shaft


204


results in response to push-type force on wheel


202


along the direction shown by direction arrow


238


. Two mounting members


510


and


512


, which are components with slot cutouts and are mountable to platform


210


, interact with and constrain shaft


204


. Two shaft collars (translation limiters)


514


and


516


interact with mounting members


510


and


512


to limit the amount of movement of shaft


204


along the directions indicated by the bi-directional arrow G


320


. In the embodiment shown in

FIGS. 14 through 17

, the mounting members


510


and


512


, shaft collars


514


and


516


, and switches


506


and


508


are preferably very similar in shape and spring response along the direction shown by direction arrow


238


; by making the members of a component type similar to others within the component type means that a simple, symmetric distribution of these components about wheel


202


is a viable design for ensuring substantial translation and uniform tactile feedback along the direction shown by direction arrow


238


. If necessary, shaft collars


514


and


516


can also be increased in diameter such that they also function as tilt-limiting features that help reduce shaft tilt and ensure substantial translation of shaft


204


. Shaft collars


514


and


516


can be separate components attached to the shaft: shaft collars


514


and


516


can also be features manufactured onto the shaft, such as steps or grooves cut into the shaft of materials molded onto the shaft.




With the configuration shown in

FIGS. 14

to


17


, when the user applies push-type force on the wheel


202


along direction F


238


, this force is transmitted through to shaft


204


and the buttons


518


and


520


of switches


506


and


508


. In response, shaft


204


, being guided by the spring-like reaction force of buttons


518


and


520


, mounting members


510


and


512


, and shaft collars


514


and


516


, substantially translates toward and depresses buttons


518


and


520


to actuate switches


506


and


508


.




Platform


210


can be any relatively rigid part that properly supports the button-wheel components. However, if platform


210


is constructed as a circuit board with conductive traces, then the sensors of the button-wheel


500


can be directly powered and their signals routed by platform


210


; this eliminates the need for additional routing components. Those skilled in the art will also note that different designs of the components shown in

FIGS. 14 through 17

are also within the scope of this embodiment. For example, shaft


204


can contain additional features such as collars and extensions to facilitate switch actuation and to limit the travel of wheel


202


or shaft


204


along the direction shown by direction arrow G


320


. The shaft can also replace shaft collars


514


and


516


with additional features such as grooves or steps to reduce cost or simplify manufacture. Alternate slot patterns in mounting members


510


and


512


are also possible, and some potential slot designs are shown in

FIGS. 18 through 20

;

FIG. 18

shows an open, straight slot


522


that may facilitate assembly,

FIG. 19

shows a closed slot that better retains shaft


204


, and

FIG. 20

shows a partially open, straight slot with small extensions near the opening to help retain shaft


204


(not shown).




Similar to other embodiments, this embodiment also only needs one second sensor (translation sensor) to be powered and connected to the button-wheel electronics for ON/OFF switch actuation. This means that either switch


506


or switch


508


can be replaced by a simple biasing member that provides the proper spring-type reaction force in response to user push-type input along the direction shown by direction arrow


238


. For example,

FIGS. 21 through 24

disclose embodiments of a button-wheel


700


that replaces switch


508


and mounting member


512


with a movable mount


702


mountable on a biasing member


704


.





FIG. 21

is a cross-sectional view of an embodiment that uses a standard extension/compression spring as a biasing member


704


mountable to the platform


210


to support movable mount


702


, and

FIG. 22

is the corresponding side view. The use of a standard extension/compression spring means that movable mount


702


also has limited mobility in directions that are not along the direction shown by direction arrow


238


; this mobility in directions that are not along the direction shown by direction arrow


238


may lead to undesirable motions of shaft


204


. However, proper design of biasing member


704


and other components that interact with shaft


204


can constrain this motion in directions that are not along the direction shown by direction arrow


238


to limit this motion to acceptable magnitudes and ensure substantial translation of shaft


204


along the direction shown by direction arrow


238


in response to push-type force on wheel


202


along the direction shown by direction arrow


238


. If necessary, additional features (not shown) and components such as linear guides for the shaft


204


or tilt-minimizing features as discussed later within this document, can also be incorporated into the button-wheel


700


to guide the translation of shaft


204


along the direction shown by direction arrow


238


.

FIG. 23

is a cross-sectional view of another embodiment that uses a flat spring for the biasing member


704


mountable to the platform


210


to support movable mount


702


, and

FIG. 24

is the corresponding side view. Depending on the construction of the button-wheel


700


, it may be easier and less costly to use flat springs instead of standard extension/compression springs; in addition, flat springs are usually more easily designed to reduce motion of shaft


204


in directions that are not along the direction shown by direction arrow


238


.




Movable mount


702


can be a component that functions as a bearing, a first sensor, and a rotary tactile feedback mechanism. However, movable mount


702


would preferably be designed to not allow shaft


204


to tilt to help ensure substantial translation of shaft


204


.





FIG. 25

depicts a variation of another embodiment of button-wheel


800


in which both ends of shaft


204


are supported by movable mounts


802


and


804


mountable on biasing member


806


and


808


and a switch


810


. The biasing members


806


and


808


and switch


810


are mountable to platform


210


. The switch


810


in the embodiment shown in

FIG. 25

combines the function of a second sensor and a biasing member placed under wheel


202


. The biasing members


806


and


808


can be flat springs designed to bias and constrain shaft


204


to substantially translate along the direction shown by direction arrow


238


in response to push-type force on wheel


202


along the direction shown by direction arrow


238


. When the user applies push-type force on wheel


202


along the direction shown by direction arrow


238


, shaft


204


substantially translates along the direction shown by direction arrow


238


and movable mounts


802


and


804


compresses biasing members


806


and


808


. With sufficient translation of shaft


204


, wheel


202


contacts and depresses button


812


of switch


810


and actuates switch


810


. Although

FIG. 25

discloses a standard pushbutton switch as a second sensor (translation sensor), alternative second sensor technologies are also viable and are within the scope of this invention.





FIG. 26

shows a variation of the embodiment depicted in

FIG. 25

in which shaft


204


has been elongated and the translation sensor or simply sensor


814


has been moved away from under wheel


202


to the side of mount


804


distal from wheel


202


and proximate to an end


816


of shaft


204


. In addition, the sensor


814


can be a non-contact breakbeam-type sensor formed from photoemitter


818


, photodetector


820


mountable to platform


210


, and an extension


822


of shaft


204


proximate to end


816


. This variation shown in

FIG. 26

can accommodate a larger wheel


202


or a lower overall button-wheel height by enabling the designer to include a gap


824


under wheel


202


(neither a larger wheel nor a shorter button-wheel height is shown in FIG.


26


). Since the sensor


814


does not apply forces on shaft


204


in response to push-type force on wheel


202


along the direction shown by direction arrow


238


, biasing members


806


and


808


are designed to have similar spring response along the direction shown by direction arrow


238


and are arranged symmetrically about wheel


202


to help ensure substantial translation and uniform tactile feedback in response to push-type force along the direction shown by direction arrow


238


. However, those skilled in the art will recognize that a switch with spring-like response can also be used and can interact with shaft


204


if its spring reaction forces are negligible compared to that of biasing members


806


and


808


, or if its forces are taken into account while designing and locating biasing members


806


and


808


. Alternative translation sensor technologies besides the breakbeam-type sensor can also be used and are within the scope of this invention. Some example second sensor technologies are described earlier for other embodiments.




The use of biasing members


806


and


808


in the embodiment shown in

FIGS. 25 and 26

means that movable mounts


802


and


804


have some limited mobility in the non-F directions. However, proper design of the biasing members


806


and


808


while keeping in mind functional characteristics such as size and spring constant, can limit this non-F motion to acceptable magnitudes. The interaction of shaft


204


with movable mounts


802


and


804


will also limit non-F motion. Additional features and components (not shown) such as linear guides for the shaft or tilt-minimizing features as discussed later within this document, can be incorporated into the button-wheel


800


to guide the translation of shaft


204


along the direction shown by direction arrow


238


.





FIGS. 27 through 34

depict another embodiment of button-wheel


900


in which platform


210


is a relatively rigid circuit board with a fixed region


901


. The circuit board includes a cutout


902


that creates a biasing member


904


formed by a flexible region (flat-spring region)


906


rimmed by the cutout


902


. Movable mount


908


is supportable by flexible region


906


.

FIG. 27

is a top view of this embodiment.

FIG. 28

is a cross sectional view of the embodiment in a state in which switch


910


is not actuated and

FIGS. 29 and 32

are corresponding side views.

FIG. 30

is a cross sectional view of the embodiment in a state in which switch


910


is actuated and

FIGS. 31 and 33

are corresponding side views. The embodiment disclosed in

FIGS. 27 through 34

has the advantage of utilizing platform


210


for multiple functions—platform


210


provides mechanical support to the button-wheel components, electrical support to the button-wheel components, and a spring bias to movable mount


908


.




When the user applies push-type force on wheel


202


along the direction shown by direction arrow


238


, shaft


204


substantially translates along the direction shown by direction arrow


238


as biasing member


904


deflects and shaft


204


depresses button


912


of switch


910


and actuates switch


910


. Shaft


204


has a first end


914


which can actually translate in a direction parallel to the direction shown by direction arrow


238


independently from a second end


916


wherein the second end


916


is located opposite the first end


914


of the shaft


204


. A mounting member


918


, switch


910


, and biasing member


904


can be configured to ensure that shaft


204


substantially translates along the direction shown by direction arrow


238


and provides uniform tactile feedback parallel to the direction shown by direction arrow


238


in response to push-type force on wheel


202


along the direction shown by direction arrow


238


. Cutout


902


also includes a void


920


formed in platform


210


, through which wheel


202


can move unabated; this allows the designer to include a larger wheel


202


or reduce the total height of the button-wheel


900


.




The embodiment depicted in

FIGS. 27 through 34

requires careful biasing of biasing member


904


; in addition, the embodiment uses biasing member


904


to facilitate the translation of movable mount


908


and switch


910


actuates through physical contact of button


912


with shaft


204


, not biasing member


904


.




Specific selection of the geometry of biasing member


904


and the material of platform


210


is necessary to achieve proper biasing and substantial translation of shaft


204


along the direction shown by direction arrow


238


in response to push-type force on wheel


202


along the direction shown by direction arrow


238


. The substantially planar and rectilinear shape of biasing member


904


shown in

FIGS. 27 through 33

is chosen to minimize manufacturing costs and the amount of tilt and motion in directions that are not along the direction shown by direction arrow


238


in shaft


204


in response to push-type force along the direction shown by direction arrow


238


. Flexible region


906


includes a mount support region located proximate to the movable mount


908


and a cantilever base region


924


located distal from the movable mount


908


(See FIGS.


27


and


33


). The cantilever base region


924


of flexible region


906


undergoes the greatest deformation while the mount support region


922


of flexible region


906


undergoes the greatest motion relative to the platform


210


. As shown in

FIG. 33

, the deflection of the biasing member


904


causes movable mount


908


to reorient in a manner that matches the rotational freedom of shaft


204


; thus, shaft


204


can accommodate this change in orientation while experiencing negligible torsion simply by rotation in the direction indicated by direction arrow


1




926


. Some translation of shaft


204


in the direction indicated by direction arrow H


928


will also occur. However, translation along direction H


928


is the least negative of the three translational directions in 3D space on ensuring substantial translation of shaft


204


, and, with the small distance typically traveled by shaft


204


, this translation along direction H


928


is negligible.




Those skilled in the art will recognize that alternate geometries for biasing member


904


may be preferable to accommodate different space constraints, to accommodate manufacturing concerns, or to produce even purer translation of shaft


204


along the direction shown by direction arrow


238


. For example, elongating biasing member


904


enables movable mount


908


to approach a pure translational motion along the direction shown by direction arrow


238


. Alternatively, a biasing member


904


formed from the flexible region


906


having geometry such the spiral pattern shown in

FIG. 34

enables movable mount


908


to approach a pure translation along the direction shown by direction arrow


238


. However, these alternatives usually require more space than the pattern shown in

FIG. 27

, and might not offer noticeable improvement in button-wheel performance above what is already achieved with the biasing member


904


shown in

FIGS. 27 through 33

.




Those skilled in the art will also note that biasing member


904


is not limited in material or in manufacture as a part of platform


210


. Biasing member


904


can be formed from other parts of the button-wheel


900


and the button-wheel host input device (not shown) as long as the biasing member


904


provides the necessary spring-like response to push-type force on wheel


202


along the direction shown by direction arrow


238


. For example, biasing member


904


can be formed as a separate component from standard spring metals such as steel or copper and incorporated into the button-wheel


900


. Biasing member


904


can also be an extension or cutout of platform


210


, an extension or cutout of a mounting bracket (not shown) for the button-wheel, or an extension or cutout of the support frame


216


manufactured from plastic, metal, composite, or other material capable of providing spring-like response. It is also contemplated that biasing member


904


can comprise of additional stiffening features or components that stiffen a highly flexible component or highly flexible region of a component that is too flexible to provide the necessary biasing force. The highly flexible component or region of a component can comprise of a flexible printed circuit or a flexible membrane with conductive traces on its surface. The additional stiffening features and additional members can comprise of extensions from a mounting bracket, extensions from the support frame


216


, or separate stiffeners that have been attached to the button-wheel specifically to stiffen the highly flexible component or highly flexible region of a component.




Although

FIGS. 14 through 17

depict only two pushbuttons as second sensors and

FIGS. 21 through 34

depict only one pushbutton as a second sensor, other numbers, types, and configurations of second sensors can also be used. These alternatives can act as backup sensors, help ensure substantial translation of shaft


204


, produce more uniform tactile feedback, or provide additional information on the translation of shaft


204


. For the embodiments shown in

FIGS. 25 through 34

, a simple way to add second sensors to the button wheel


800


,


900


is to include strain gauges that produce signals in response to the deformation of biasing members


806


,


808


, or


904


. Additional examples of alternative second sensor technologies are also disclosed in the above descriptions of embodiments.




Similar to the earlier discussed embodiments, this embodiment can also utilize second sensors and methods that enable the button-wheel to sense multiple levels of translation (extent of translation) and estimate the magnitude and location of the push-type force on wheel


202


along the direction shown by direction arrow


238


. In addition, the components of the earlier embodiments can also be mounted in different locations, on alternate surfaces, and in different orientations to accommodate different design constraints; the designer must only ensure these changes do not alter the functionality of the button-wheel


800


,


900


. Different designs of shaft


204


are also viable, and shaft


204


can contain additional features such as collars and extensions to facilitate switch actuation and to limit the travel of shaft


204


along the direction shown by the direction arrow G


320


. Alternate mounting member designs are also viable, and

FIGS. 18 through 20

depict some alternatives.




In this embodiment, shaft


204


will usually tilt to some extent; however, in most applications, a moderate amount of tilt is acceptable since the resulting motion is still substantially translational.

FIGS. 35 through 41

disclose some methods to produce a smoother and more uniform translational motion for shaft


204


by reducing the undesirable tilt of shaft


204


.

FIG. 35

shows a partial cross-section of an embodiment of button-wheel


1000


having a tilt reducer mechanism composed of a stop member


1002


with a cylindrical shape mountable on shaft


204


. Stop


1002


interacts with movable mount


1004


. Rotational motion of wheel


202


about its axis is impeded minimally by the interaction between stop member


1002


and movable mount


1004


. However, forces and moments which may lead to shaft


204


tilt causes stop member


1002


to contact movable mount


1004


; these tilting forces are then absorbed by movable mount


1004


and transmitted to a base


1006


(which may be platform


210


or flexible region


906


in other embodiments) on which movable mount


1004


is mountable. Shaft


204


tilts only as much as allowed by stop member


1002


, movable mount


1004


, and base


1006


. Stop member


1002


can also be made at least a part of a rotational feedback detent mechanism or a first sensor encoder mechanism to simplify assembly, reduce costs, or reduce component count.





FIGS. 36 and 37

show an embodiment of a button-wheel


1100


in which a tilt reducer mechanism comprises of an additional mount


1102


working in conjunction with movable mount


1104


to reduce the undesirable tilting of shaft


204


during switch actuation. Additional mount


1102


is mountable to base


1106


. Additional mount


1102


limits the travel of second end


1108


of shaft


204


relative to movable mount


1104


, parallel to the direction shown by direction arrow


238


, and helps keep shaft


204


in line with cutout


1110


formed in additional mount


1102


and movable mount


1104


. Additional mount


1102


can contain any cutout shape that limits the travel of shaft


204


relative to movable mount


1104


parallel to the direction shown by direction arrow


238


. Some examples in addition to the circular cutout shown in

FIGS. 36 and 37

are depicted in

FIGS. 38

to


40


.

FIG. 38

shows a horizontal cutout


1112


formed in additional mount


1102


,

FIG. 39

shows a slanted cutout


1114


formed in additional mount


1102


, and

FIG. 40

shows an L-shape cutout


1116


formed in additional mount


1102


. These alternatives may make button-wheel assembly easier than a pure circular cutout. The actual cutout shape will be determined by the geometry of the button-wheel.





FIG. 41

is a partial cross-sectional view of an embodiment having a tilt reducer mechanism comprising a hard stop


1118


(hard stop


1118


is not labeled in

FIG. 41

) mountable to the base


1106


under shaft


204


. The hard stop


1118


can be used in conjunction with movable mount


1104


to minimize the undesirable tilting of shaft


204


during switch actuation. Rotational motion of wheel


202


about its axis is impeded minimally by the interaction between shaft


204


and hard stop


1118


. However, forces and moments which may lead to shaft


204


tilt causes shaft


204


to impact hard stop


1118


and transmit these forces and moments into base


1106


. This limits the motion of shaft


204


relative to movable mount


1104


and thus the tilting of shaft


204


.




The additional features and components disclosed in

FIGS. 35 through 41

can also be made at least a part of a rotational feedback detent mechanism or a first sensor encoder mechanism to simplify assembly, reduce costs, or reduce component count.




Those skilled in the art will note that even if the button-wheel design of the embodiments disclosed utilizes no tilt-limiting techniques, the substantially translational action is still a significant improvement on the substantially tilting action of prior art button-wheel devices.




For both the embodiments disclosed, those skilled in the art will note that many additional variations on these two preferred button-wheel embodiments are viable and still retain equivalence. Such variations include, but are not limited to, the following. The exact component technologies and types can change; for example, the wheel encoder can be optical or mechanical. The component sizes and shapes can also vary. For example, the wheel can be disc-like, cylindrical, spherical, have circular cross-section, have polygonal cross section, or have variable cross-sectional shape across the width of the wheel; the shaft may also vary in cross-section, and contain any stepped or rounded features as necessary to achieve its functions or to simplify button-wheel manufacture. The component mounting methods and mounting locations can differ. For example, the mounting member can be mountable on the bottom, top, or sides of the support frame, on ribs or extensions of the support frame, or on the circuit board supporting the button, encoder, and other electronics. The button-wheel may also utilize combination parts that perform the function of many components. For example, the mount and encoder can be combined into one part, the detent mechanism and the wheel can be combined into one part, or the wheel can be molded onto the shaft or a region of the shaft can function as the wheel. The button-wheel may also utilize components fashioned from many sub-parts. For example, the encoder can consist of a photoemitter, an encoder disc, and a photodetector and utilize breakbeam-type technology.




While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.



Claims
  • 1. A button wheel comprising:a support frame including a first region and a second region, said first region being a spring region; a first mount disposed on said first region of said support frame; a second mount spaced apart from said first mount and disposed on said support frame at said second region; a translation sensor mounted at a fixed position with respect to said support frame; a shaft disposed along an axis and including a wheel mounted thereon, said shaft including a first end rotatably engaged in said first mount and a second end rotatably and translatably engaged in said second mount so as to allow said shaft to translate with respect to said support frame in a direction substantially perpendicular to said axis to actuate said translation sensor upon the application of mechanical force to said wheel having a component substantially along said direction; and a rotation sensor in operative communication with said wheel.
  • 2. The button wheel of claim 1 wherein said translation sensor is selected from the group consisting of a pushbutton switch, a snap dome switch, a breakbeam sensor, a strain gauge and a proximity sensor.
  • 3. The button wheel of claim 1 wherein said first region of said support frame is configured with a spiral pattern geometry.
  • 4. The button wheel of claim 1 wherein said first region of said support frame is formed as an L shaped region.
  • 5. The button wheel of claim 1 wherein said first region of said support frame is formed as a straight region.
  • 6. The button wheel of claim 1 wherein said support frame includes an aperture formed thereon and wherein said wheel is at least partially disposed in said aperture when said wheel is translated.
  • 7. The button wheel of claim 1 wherein said support frame includes an aperture formed thereon and wherein said wheel is at least partially disposed in said aperture when said wheel is at rest.
  • 8. The button wheel of claim 1 wherein said first region is a flat-spring region.
  • 9. The button wheel of claim 1 further comprising at least one biasing member coupled to said support frame.
  • 10. The button wheel of claim 1 wherein said translation sensor includes a biasing member.
  • 11. The button wheel of claim 1 further comprising at least one additional translation sensor.
  • 12. The button wheel of claim 1 wherein said translation sensor includes a button mounted proximate to said support frame.
  • 13. The button wheel of claim 1 wherein said translation sensor is comprises at least one strain gauge integral with said support fame.
  • 14. The button wheel of claim 1 wherein said translation sensor is configured to provide a signal that varies as a function of the extent of translation from a rest position in said direction.
  • 15. The button wheel of claim 1 wherein said second region is a fixed region.
  • 16. The button wheel of claim 1 further comprising:a first translation limiter disposed on said shaft proximate said first end and adjacent to said first mount to limit the translation of said shaft along said axis; a second translation limiter disposed on said shaft proximate said second end and adjacent to said second mount to limit the translation of said shaft along said axis.
  • 17. The button wheel of claim 1 wherein said translation sensor senses extent of translation.
  • 18. The button wheel of claim 1 wherein said translation sensor is configured to estimate position of an input force.
  • 19. The button wheel of claim 1 wherein said shaft includes a distal extension on one of said first end and said second end, and said translation sensor is disposed in operative communication with said shaft at a location proximate to said distal extension.
  • 20. The button wheel of claim 1 wherein said translation sensor is configured to sense at least three discrete translation positions of said wheel.
  • 21. A button-wheel comprising:a base; a shaft rotatably coupled to said base about an axis of rotation and translatable in a direction substantially perpendicular to said axis of rotation; a wheel fixedly mounted on said shaft; a translation sensor in operative communication with said wheel and configured to sense at least three discrete translation positions of said wheel in said direction substantially perpendicular to said axis of rotation.
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