Integrated keypad interface for a personal digital assistant device

TECHNICAL FIELD

The present invention generally relates to the field of electronic devices. More particularly, the present invention relates to the field of personal digital assistants (PDAS) or other types of portable electronic devices.

BACKGROUND ART

Computers and other electronic devices have become integral tools used in a wide variety of different applications, such as in finance and commercial transactions, computer-aided design and manufacturing, health care, telecommunication, education, etc. Computers along with other electronic devices are finding new applications as a result of advances in hardware technology and rapid development in software technology. Furthermore, the functionality of a computer system or other type of electronic device is dramatically enhanced by coupling these type of stand-alone devices together in order to form a networking environment. Within a networking environment, users may readily exchange files, share information stored on a common database, pool resources, and communicate via electronic mail (e-mail) and via video teleconferencing. Furthermore, computers along with other types of electronic devices which are coupled to the Internet provide their users access to data and information from all over the world. Computer systems have become useful in many aspects of everyday life both for personal and business uses.

Included within this broad category of computers and electronic devices is the personal digital assistant (commonly referred to as a PDA). Specifically, as the components required to build a computer system have been greatly reduced in size, new categories of computer systems have emerged. One of these new categories of computer systems is the personal digital assistant. A personal digital assistant is a portable computer system which is small enough to be held in the hand of its user and can be “palm-sized.”

Since personal digital assistants are very small, full-sized keyboards are generally not efficient input devices. For instance, personal digital assistants using keyboards usually have keyboard devices that are so small that a user typically cannot touch-type on them. Many personal digital assistants employ a stylus and a digitizer pad as an input system. The stylus and digitizer pad work well for personal digital assistants because the arrangement allows a user to hold the personal digital assistant in one hand while writing with the stylus onto the digitizer pad with the other hand. A small on-screen keyboard image can also be used for data entry. Because of the elimination of the keyboard, personal digital assistants are very portable and tend to be carried by the user wherever they go, including on travel.

Furthermore, the personal digital assistant is usually a battery powered device that is typically used as an electronic organizer having the capability to store and display a wide range of information which can include numerous addresses and telephone numbers of business and personal acquaintances, financial information, daily appointments, “to do” list, along with various other personal information. In this manner, the personal digital assistant is able to consolidate a variety of information which is easily accessible by its user. Therefore, personal digital assistants are very useful and powerful devices.

It should be appreciated that there are disadvantages associated with personal digital assistants. For example, between the top cover and parameter of each button of a typical personal digital assistant there is a gap which is an entrance area for dirt and/or grim that is capable of stopping one or more of the buttons from functioning properly. Specifically, the activation travel distance of each button of the typical personal digital assistant may be as small as 0.3 millimeters (mm). As such, particles of dirt and/or grim (e.g., from a user's hand) may get underneath one (or more) of the buttons via the parameter gaps surrounding the buttons and thereby obstruct its very small functional movement.

DISCLOSURE OF THE INVENTION

Accordingly, a need exists for a method and apparatus that provides a seal for the buttons of a personal digital assistant that restricts dirt, grim, and other foreign particles from getting underneath them. Embodiments of the present invention provide a method and apparatus which accomplish the above mentioned need.

One embodiment in accordance with the present invention includes a “plug-in” button module for a personal digital assistant (PDA). Specifically, the “plug-in” button module includes a button frame module having a flexible membrane layer (e.g., thermo-plastic urethane or thermo-plastic elastomer) molded over it. The plug-in module can be snapped into the personal digital assistant over its button array. In this manner, the plug-in button module provides a seal for the buttons of the personal digital assistant that restricts dirt, grim, and other foreign particles from getting underneath them. Furthermore, since the plug-in button module is modular, it can be manufactured separately from the rest of the personal digital assistant in a wide variety of ways. For example, the membrane layer of the plug-in button module can be fabricated with different shapes, colors, hardnesses, decorations, textures, and opacities. In this manner, a user is able to personalize their personal digital assistant by snapping in a particular plug-in button module.

In another embodiment, the present invention includes a removable button module for covering a button of a portable computing device. The removable button module includes a button frame module forming a cavity that aligns with the button of the portable computing device. Furthermore, the removable button module includes a membrane layer disposed on an outer side of the button frame module and covering an opening of the cavity. It is understood that the removable button module is for attaching to the portable computing device to cover the button of the portable computing device. The membrane layer is disposed over the button frame module when the removable button module is attached to the portable computing device to cover the button.

The present invention provides these advantages and others which will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of embodiments in accordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

FIG. 1

is a system illustration of a personal digital assistant connected to other computer systems and the Internet via a cradle device.

FIG. 2A

is a top side perspective view of an exemplary personal digital assistant computer system.

FIG. 2B

is a bottom side perspective view of the personal digital assistant of FIG.

2

A.

FIG. 3

is an exploded view of the components of the personal digital assistant of FIG.

2

A.

FIG. 4

is a perspective view of the cradle device for connecting the personal digital assistant to other systems via a communication interface.

FIG. 5

is a logical block diagram of exemplary circuitry of the personal digital assistant of FIG.

2

A.

FIG. 6

is a top view of components of an exemplary “plug-in” button module in accordance with an embodiment of the present invention.

FIG. 7

is a top view of an exemplary personal digital assistant implemented with a “plug-in” button module in accordance with an embodiment of the present invention.

FIGS. 8A and 8B

are perspective views illustrating one embodiment of how a “plug-in” button module can be coupled to a top cover of a personal digital assistant in accordance with the present invention.

FIG. 9

is a top view of an exemplary personal digital assistant implemented with another plug-in button module in accordance with an embodiment of the present invention.

FIG. 10

is a top view of another exemplary membrane layer that may be coupled to a plug-in button module in accordance with an embodiment of the present invention.

FIG. 11

is a top view of yet another exemplary membrane layer that may be coupled to a plug-in button module in accordance with an embodiment of the present invention.

FIG. 12

illustrates a flowchart of steps performed in accordance with one embodiment of the present invention for designing and fabricating an interchangeable button module that covers buttons of a portable computing device.

The drawings referred to in this description should not be understood as being drawn to scale except if specifically noted.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of fed the present invention, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be obvious to one of ordinary skill in the art that the present invention may be practiced without these specific details. In other instances, well known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present invention.

An embodiment of the present invention may be incorporated with a portable computing device such as a personal digital assistant computing device. It should be understood that the descriptions corresponding to

FIGS. 1-5

provide some general information about personal digital assistants.

FIG. 1

illustrates a system

50

that may be used in conjunction with a personal digital assistant computer system

100

. Specifically, system

50

comprises a host computer system

56

which can either be a desktop unit as shown, or, alternatively, can be a laptop system

58

. Optionally, one or more host computer systems can be used within system

50

. Host computer systems

58

and

56

are shown connected to a communication bus

54

, which in one embodiment can be a serial communication bus, but could be of any of a number of well known designs, e.g., a parallel bus, Ethernet, Local Area Network (LAN), etc. Optionally, bus

54

can provide communication with the Internet

52

using a number of well known protocols.

Importantly, bus

54

is also coupled to a cradle

60

for receiving and initiating communication with personal digital assistant

100

. Cradle

60

provides an electrical and mechanical communication interface between bus

54

(and anything coupled to bus

54

) and the portable computer system

100

for two way communications. Computer system

100

also contains a wireless infrared communication mechanism

64

for sending and receiving information from other devices.

FIG. 2A

is a perspective illustration of the top face

100

a

of an exemplary personal digital assistant computer system. The top face

110

a

contains a display screen

105

surrounded by a bezel or cover. A removable stylus

80

is also shown. The display screen

105

is a touch screen able to register contact between the screen and the tip of the stylus

80

. The stylus

80

can be fabricated of any material to make contact with the screen

105

. The top face

100

a

also contains one or more dedicated and/or programmable buttons

75

for selecting information and causing the computer system to implement functions. The on/off button

95

is also shown.

FIG. 2A

also illustrates a handwriting recognition pad or “digitizer” containing two regions

106

a

and

106

b

. For example, region

106

a

is for the drawing of alpha characters therein for automatic recognition and region

106

b

is for the drawing of numeric characters therein for automatic recognition. The stylus

80

is used for stroking a character within one of the regions

106

a

and

106

b

. The stroke information is then fed to an internal processor for automatic character recognition. Once characters are recognized, they are typically displayed on the screen

105

for verification and/or modification.

FIG. 2B

illustrates the bottom side

100

b

of one embodiment of the personal digital assistant computer system. An optional extendible antenna

85

is shown and also a battery storage compartment door

90

is shown. A communication interface

108

is also shown. In one embodiment of the present invention, the serial communication interface

108

is a serial communication port, but could also alternatively be of any of a number of well known communication standards and protocols, e.g., parallel, small computer system interface (SCSI), Ethernet, Firewire (IEEE 1394), Universal Serial Bus (USB), etc.

FIG. 3

is an exploded view of the personal digital assistant computer system

100

. Computing device

100

contains a top cover

210

having an outline of region

106

and holes

75

a

for receiving a button array

75

b

. A flat panel display

105

(both liquid crystal display and touch screen) fits into top cover

210

. It is appreciated that any of a number of display technologies can be used, e.g., liquid crystal display (LCD), field emission device (FED), plasma, etc., for the flat panel display

105

. A battery

215

provides electrical power. A contrast adjustment (potentiometer)

220

is also shown. On/off button

95

is shown along with an infrared emitter and detector device

64

. A flex circuit

230

is shown along with a printed circuit (PC) board

225

containing electronics and logic (e.g., memory, communication bus, processor, etc.) for implementing computer system functionality. The digitizer pad is also included in PC board

225

. A midframe

235

is shown along with stylus

80

. Position adjustable antenna

85

is also shown.

A radio receiver/transmitter device

240

is also shown between the midframe and the rear cover

245

of FIG.

3

. The receiver/transmitter device

240

is coupled to the antenna

85

and also coupled to communicate with the PC board

225

. In one implementation, the Mobitex wireless communication system is used to provide two way communication between system

100

and other networked computers and/or the Internet via a proxy server.

FIG. 4

is a perspective illustration of one embodiment of the cradle

60

for receiving the personal digital assistant computer system

100

. The cradle

60

contains a mechanical and electrical interface

260

for interfacing with serial connection

108

(

FIG. 2B

) of computer system

100

when system

100

is slid into the cradle

60

in an upright position. Once inserted, button

270

can be pressed to initiate two way communication between system

100

and other computer systems coupled to serial communication

54

.

FIG. 5

is a block diagram of exemplary circuitry of computer system

100

, some of which can be implemented on PC board

225

. The personal digital assistant

100

includes an address/data bus

99

for communicating information, a central processor

101

coupled with the bus

99

for processing information and instructions. Central processor unit

101

may be a microprocessor or any other type of processor. The computer system

100

also includes data storage features such as a volatile memory unit

102

(e.g., random access memory, static RAM, dynamic RAM, etc.) coupled with the bus

99

for storing information and instructions for the central processor

101

and a non-volatile memory unit

103

(e.g., read only memory, programmable ROM, flash memory, EPROM, EEPROM, etc.) coupled with the bus

99

for storing static information and instructions for the processor

101

. Computer system

100

may also include an optional data storage device

104

(e.g., memory stick) coupled with the bus

99

for storing information and instructions. It should be appreciated that device

104

can be removable. As described above, system

100

also contains a display device

105

coupled to the bus

99

for displaying information to the computer user. It is understood that PC board

225

can contain the processor

101

, the bus

99

, the volatile memory unit

102

, and the non-volatile memory unit

103

.

Also included in computer system

100

of

FIG. 5

is an optional alphanumeric input device

106

which in one implementation is a handwriting recognition pad (“digitizer”) having regions

106

a

and

106

b

(FIG.

2

A), for instance. Device

106

can communicate information and command selections to the central processor

101

. System

100

also includes an optional cursor control or directing device

107

coupled to the bus

99

for communicating user input information and command selections to the central processor

101

. In one implementation, device

107

is a touch screen device incorporated with screen

105

. Device

107

is capable of registering a position on the screen

105

where a stylus makes contact. The display device

105

utilized with the computer system

100

may be a liquid crystal device (LCD), cathode ray tube (CRT), field emission device (FED, also called flat panel CRT) or other display device suitable for creating graphic images and alphanumeric characters recognizable to the user. In the preferred embodiment, display

105

is a flat panel display. Computer system

100

also includes signal communication device

108

, which is also coupled to bus

99

, and can be a serial port for communicating with the cradle

60

. Device

108

can also in include an infrared communication port.

Exemplary Plug-in Button Module in Accordance with the Present Invention

It should be appreciated that

FIGS. 6 and 7

are described in conjunction in order to more fully describe the structure of the present embodiment.

FIG. 6

is a top view of components of an exemplary “plug-in” button module

600

in accordance with an embodiment of the present invention. Additionally,

FIG. 7

is a top view of an exemplary personal digital assistant

700

implemented with the “plug-in” button module

600

in accordance with an embodiment of the present invention. Specifically, the plug-in button module

600

(

FIG. 6

) includes a button frame module

604

and a flexible membrane layer

602

that is molded over or attached to an outer side

608

of button frame module

604

. Since the plug-in button module

600

is modular, it can be manufactured separately from the rest of the personal digital assistant

700

in a wide variety of ways. For example, the flexible membrane layer

602

of the plug-in button module

600

can be fabricated having different shapes, colors, hardnesses, decorations, textures, and opacities. In this manner, a user is able to personalize their personal digital assistant (e.g.,

700

) by attaching or detaching a particular plug-in button module (e.g.,

600

).

There are advantages associated with the plug-in button module

600

of the present embodiment. One of the advantages is that the button module

600

provides more flexibility during the assembly of personal digital assistants (e.g.,

700

). For example, some manufacturers of personal digital assistants are moving toward painted products. By using the plug-in button module

600

, the manufacturer may color the membrane

602

in order to match the color of the painted color of the top cover (e.g.,

702

) of the personal digital assistant

700

. Furthermore, the manufacturer may color the membrane

602

in order to compliment the color of the painted color of the top cover of the personal digital assistant

700

. Another advantage associated with the plug-in button module

600

is that its membrane layer

602

and button frame module

604

may be fabricated with different materials that may provide different benefits. However, these different materials may have different shrink rates. As such, it is easier to work with these different materials when working with button module

600

instead of working with a whole top cover (e.g.,

210

) of a personal digital assistant.

It is understood that personal digital assistant

700

of

FIG. 7

has similar components and functionality as personal digital assistant

100

described above with reference to

FIGS. 1-5

. However, top cover

702

of personal digital assistant

700

does not cover its button array (e.g.,

75

b

) in the manner that computer system

100

is shown. Instead, plug-in button module

600

is designed to attach to personal digital assistant

700

over its button array (not shown). In this manner, the plug-in button module

600

provides a seal for the buttons (e.g.,

75

) of the personal digital assistant

700

which restricts dirt, grim, and other foreign particles from getting underneath them. It is appreciated that the buttons (e.g.,

75

) of personal digital assistant

700

located underneath the membrane layer

602

may be flat, concave, and/or convex in accordance with the present embodiment.

The flexible membrane layer

602

of the plug-in button module

600

of

FIGS. 6 and 7

may be fabricated from a wide variety of materials. For example, the membrane layer

602

may include thermo-plastic urethanes (TPUs), thermo-plastic elastomers (TPEs), silicones, rubbers, leathers, nylons, and the like. It should be understood that membrane layer

602

of the present embodiment is not limited to these particular materials. Additionally, the button frame module

604

of the plug-in button module

600

may also be fabricated from a wide variety of materials. For example, the button frame module

604

may be fabricated from polycarbonites, plastics, metals, alloys, nylons, and the like. However, button frame module

604

of the present embodiment is not limited to these particular materials.

The button frame module

604

of

FIG. 6

also includes vertical cavities (holes)

606

which match the configuration of the button array (e.g.,

75

b

) that is implemented with personal digital assistant

700

. In this manner, the vertical cavities

606

align with and accept the button array of personal digital assistant

700

. As such, the button frame module

604

fits over the button array (e.g.,

75

b

) and attaches to the personal digital assistant

700

while the flexible membrane layer

602

completely conceals the buttons from view as shown in FIG.

7

. It is appreciated that when button module

600

is attached to personal digital assistant

700

, the membrane layer

602

may be touching (or located very close to) the buttons (e.g.,

75

) of personal digital assistant

700

. Therefore, a user of personal digital assistant

700

is able to activate one of its buttons (e.g.,

75

) by apply increasing pressure to the flexible membrane layer

602

located above the desired button until the button's activation travel distance is reached.

FIG. 7

illustrates one embodiment of the flexible membrane layer

602

of the “plug-in” button module

600

in accordance with the present invention that is fabricated from a material that may accept pad printing of (for example) different icons. Furthermore, some of the materials of the membrane layer

602

that accept pad printing may need to have an overcoat process performed on top of the pad printing. The purpose for the overcoat process is to protect the pad printing from wearing off too quickly from the membrane layer

602

. It is understood that the overcoat process may include different overcoat materials in accordance with the present embodiment.

Within another embodiment (not shown) of flexible membrane layer

602

of the plug-in button module

600

, different icons may be imprinted into the material of membrane layer

602

in accordance with the present invention. Moreover, in yet another embodiment (not shown) of flexible membrane layer

602

of the plug-in button module

600

, pad printing may be performed into icons that have been imprinted into the material of membrane layer

602

in accordance with the present invention.

The stiffness of the membrane layer

602

of the present embodiment of

FIGS. 6 and 7

may include a durometer reading as low as

40

but not as high as

70

. However, the membrane layer

602

the present embodiment is not restricted by this durometer range. Instead, the membrane layer

602

the present embodiment is well suited to be implemented with a material having any durometer reading.

FIGS. 8A and 8B

are perspective views illustrating one embodiment of how plug-in button module

600

can be attached to the top cover

702

of personal digital assistant

700

. It is appreciated that the top cover

702

of personal digital assistant

700

and the plug-in button module

600

are shown facing downward. As such,

FIG. 8A

provides a backside view of the top cover

702

and the plug-in button module

600

. Within the present embodiment,

FIG. 8B

illustrates that the plug-in button module

600

attaches into the top case

702

from its backside and then the combined unit would be attached to the rest of the components of personal digital assistant

700

. It should be understood that this kind of assembling may be done by the manufacturer of personal digital assistant devices.

In another embodiment (not shown) of the present invention, the plug-in button module

600

may be designed to be removably attached to the midframe (e.g.,

235

) instead of the top case

702

of the personal digital assistant

700

. In this manner, a user of personal digital assistant

700

may be able to physically attach and detach the plug-in button module

600

to the midframe (e.g.,

235

) of personal digital assistant

700

. Therefore, the user is able to attach and detach different types of plug-in button modules (e.g.,

600

) as desired.

Moreover, in yet another embodiment (not shown) of the present invention, the plug-in button module

600

may be designed to be removably attached to the top cover

702

from its front-side. In this manner, a user of personal digital assistant

700

may be able to physically attach and detach the plug-in button module

600

to the top cover

702

of personal digital assistant

700

. As such, the user is able to attach and detach different types of plug-in button modules (e.g.,

600

) as desired.

FIG. 9

is a top view of an exemplary personal digital assistant

700

a

implemented with a “plug-in” button module

600

a

in accordance with an embodiment of the present invention. Specifically, personal digital assistant

700

a

of

FIG. 9

is similar to personal digital assistant

700

of FIG.

7

. However, personal digital assistant

700

a

is implemented with the plug-in module

600

a

that has a raised button shape. As mentioned above, it is understood that the flexible membrane layer

602

a

may be fabricated to have different shapes in accordance with the present embodiment.

FIG. 10

is a top view of an exemplary membrane layer

602

x

that may be attached to a button frame module (e.g.,

604

) in accordance with an embodiment of the present invention. Specifically, membrane layer

602

x

includes a tab

1002

of extra membrane material that extends underneath the power button

95

of personal digital assistant

700

and/or

700

a

. One of the purposes of tab

1002

of membrane layer

602

x

is to supply a return to zero force to the power button

95

so that it returns to a flush position with top case

702

after it has been depressed.

FIG. 11

is a top view of an exemplary membrane layer

602

y

that may be attached to a button frame module (e.g.,

604

) in accordance with an embodiment of the present invention. Specifically, membrane

602

y

is fabricated such that it extends around the parameter of the active area of the digitizer area (e.g.,

105

,

106

a

, and

106

b

) and underneath the display opening of the top cover

702

of personal digital assistant

700

(and/or

700

a

). One of the purposes of membrane

602

y

of the present embodiment is to function as a gasket that seals the front of personal digital assistant

700

(and/or

700

a

) when it is completely assembled and thereby makes it splash proof to liquids. Therefore, personal digital assistant

700

(and/or

700

a

) would not be adversely affected if a liquid was accidentally spilled on the top of it.

FIG. 12

illustrates a flowchart

1200

of steps performed in accordance with one embodiment of the present invention for designing and fabricating an interchangeable button module (e.g.,

600

) that covers buttons of a portable computing device. Although specific steps are disclosed in flowchart

1200

, such steps are exemplary. That is, the present invention is well suited to performing various other steps or variations of the steps recited in FIG.

12

. Within the present embodiment, it should be appreciated that the steps of flowchart

1200

may be performed by software or hardware or any combination of software and hardware.

At step

1202

, the present embodiment designs and fabricates a frame module (e.g.,

604

) that may be coupled to the buttons (e.g.,

75

) of a portable computing device. It is appreciated that the frame module of step

1202

may also be designed to cover (but not couple to) the buttons of a portable computing device in accordance with the present embodiment. Additionally, the portable computing device of the present embodiment is well suited to be a wide variety of devices. For example, the portable computing device may be a mobile phone, pager, personal digital assistant (e.g.,

700

), and the like. Furthermore, the frame module of step

1202

may be fabricate from a wide variety of materials (e.g., polycarbonites, plastics, metals, alloys, nylons, and the like) in accordance with the present embodiment.

In step

1204

of

FIG. 12

, the present embodiment disposes a membrane layer (e.g.,

602

) on an outer side of the frame module (e.g.,

604

). It is understood that at step

1202

the membrane layer may be molded over the frame module or it may be attached to the button frame module in accordance with the present embodiment. Additionally, the membrane layer may include thermoplastic urethanes (TPUs), thermoplastic elastomers (TPEs), silicones, rubbers, leathers, nylons, and the like in accordance with the present embodiment. It is understood that once step

1204

is complete, a button module has been fabricated in accordance with the present embodiment.

At step

1206

, the present embodiment designs and fabricates a part of the portable computing device so that the button module (e.g.,

600

) may be attached to it and cover its buttons (e.g.,

75

). For example, the part of the portable computing device that the button module may be designed to couple to may include the portable computing device's top cover (e.g.,

702

), its midframe (e.g.,

235

), or its rear cover (e.g.,

245

). After the completion of step

1206

, the present embodiment exits flowchart

1200

.

Accordingly, embodiments of the present invention provide a method and apparatus that provide a seal for the buttons of a personal digital assistant device that restricts dirt, grim, and other foreign particles from getting underneath them.

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.