FIELD OF DISCLOSURE
[0001] The present disclosure relates to electronic devices, including but not limited to,
key apparatus for use with electronic devices and related methods.
BACKGROUND
[0002] Electronic devices, including portable electronic devices, have gained widespread
use and may provide a variety of functions including, for example, telephonic, electronic
messaging, and other personal information manager (PIM) application functions. Portable
electronic devices include, for example, several types of mobile stations such as
simple cellular telephones, smart telephones, wireless personal digital assistants
(PDAs), and laptop computers with wireless 802.11 or Bluetooth capabilities.
[0003] Portable electronic devices such as PDAs or smart telephones are generally intended
for handheld use and ease of portability. With continued demand for decreased size
of portable electronic devices, electronic devices continue to decrease in size. Thus,
smaller devices are generally desirable for portability. Often these portable electronic
devices include physical side keys (e.g., depressible keys, plastic keys, etc.) to
input information. However, physical keys typically employ an electrical switch assembly
that is soldered to a circuit board. As a result, coupling an electrical switch assembly
to a circuit board typically results in an electronic device having a larger dimensional
envelope or size.
[0004] EP-A-0917167 discloses an electronic device with a keypad of the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005]
FIG. 1 is a block diagram of an example portable electronic device in accordance with
the teachings disclosed herein.
FIG. 2 is an example portable electronic device of FIG. 1 implemented with an example
keypad apparatus in accordance with the teachings disclosed herein.
FIG. 3 is an exploded view of the example keypad apparatus of the electronic device
of FIG. 2.
FIG. 4 is perspective view of the example keypad apparatus of FIG. 2 and FIG. 3.
FIG. 5A is a plan view of the example keypad apparatus of FIGS. 2-4.
FIG. 5B is another perspective view of the example keypad apparatus of FIGS. 2-4 and
5A.
FIG. 6 is a cross-sectional view of the example keypad apparatus of FIGS. 2-4, 5A
and 5B taken along line 6-6 of FIG. 4.
FIG. 7 is a cross-sectional view similar to FIG. 6, but illustrating another example
keypad apparatus in accordance with the teachings disclosed herein.
FIG. 8 illustrates another example keypad apparatus in accordance with the teachings
disclosed herein mounted to a circuit board.
FIG. 9 is an exploded view of the example keypad apparatus of FIG. 8.
FIG. 10 is a perspective view of the example keypad apparatus of FIG. 8 and FIG. 9.
FIG. 11 illustrates the example keypad apparatus of FIGS. 8-10 flush mounted relative
to a circuit board.
FIG. 12 is a flowchart of an example method that may be used to manufacture an example
switch assembly disclosed herein.
DETAILED DESCRIPTION
[0006] Example keypad apparatus and methods disclosed herein reduce an overall dimensional
envelope of an electronic apparatus. To generate an electrical signal when a key of
the keypad apparatus is activated, the keypad apparatus employs an electrical switch.
An example electrical switch described herein may include one or more collapsible
dome switches associated with, or corresponding to, a depressible key of a keypad
and electrical or conductive contacts of a circuit board. For example, an electrical
switch apparatus disclosed herein is electrically coupled to a circuit board to generate
an electrical signal when a key associated with the electrical switch is activated.
[0007] More specifically, the example keypad apparatus disclosed herein may employ a carrier
to electrically couple the example electrical switch to the circuit board. In particular,
a dome switch collapses toward a conductive contact formed or printed on the carrier.
In turn, the conductive contact of the electrical switch is electrically coupled to
the circuit board via a plurality of conductive traces formed on one or more surfaces
of the carrier between the conductive contact and a conductive element of a circuit
board (e.g., an integrated circuit). In some instances, the example carriers are electrically
coupled to a side surface (e.g., plated with conductive material) of the circuit board
substantially perpendicular to a main surface of the circuit board (e.g., a surface
generally parallel relative to a display of an electronic device). In some examples,
the example carriers disclosed herein employ flexible fingers, arms or structures
that engage a side surface of a circuit board. For example, the flexible fingers may
engage respective ones of machined and electrically plated through holes or slots
of the circuit board to electrically couple the carrier to the circuit board. For
example, the conductive traces may be printed or provided on the flexible fingers
which engage the plated slots to electrically couple the dome switch to the circuit
board via the carrier. In some examples, a rear or vertical surface of the carrier
includes a conductive trace or wire that engages the side surface of the circuit board
to electrically couple the conductive contact to the circuit board.
[0008] Additionally or alternatively, the carrier mechanically couples the dome-switch to
the circuit board via, for example, frictional interference and/or interference fit.
For example, the example carriers disclosed herein may employ flexible fingers that
provide a spring bias that produces a force normal to the point of contact between
the fingers and the circuit board when the carrier is coupled to the circuit board.
As a result, the example carriers disclosed herein retain the carrier in engagement
(e.g., in frictional engagement) with the circuit board in a relatively fixed position
relative to the circuit board without the use of fasteners (e.g., chemical fasteners,
mechanical fasteners, solder, etc.). In this manner, for example, the example keypad
apparatus disclosed herein reduce cost associated with soldering the carrier to the
circuit board. In some examples, the carrier may be at least partially disposed in
a recess or cavity of a circuit board.
[0009] An example carrier disclosed herein is composed of plastic and the conductive contact
and/or the plurality of conductive traces are printed on the carrier via, for example,
Laser Direct Structuring manufacturing process or techniques.
[0010] For simplicity and clarity of illustration, reference numerals may be repeated among
the figures to indicate corresponding or analogous elements. Numerous details are
set forth to provide an understanding of the examples described herein.
[0011] The disclosure generally relates to an electronic device, such as a portable electronic
device as described herein. Examples of electronic devices include mobile, or handheld,
wireless communication devices such as pagers, cellular phones, cellular smart-phones,
wireless organizers, personal digital assistants, wirelessly enabled notebook computers,
tablet computers, mobile internet devices, electronic navigation devices, and so forth.
The electronic device may be a portable electronic device without wireless communication
capabilities, such as a handheld electronic game, digital photograph album, digital
camera, media player, e-book reader, and so forth.
[0012] A block diagram of an example portable electronic device 100 is shown in FIG. 1.
The electronic device 100 includes multiple components, such as a processor 102 that
controls the overall operation of the electronic device 100. Communication functions,
including data and voice communications, are performed through a communication subsystem
104. Data received by the electronic device 100 is decompressed and decrypted by a
decoder 106. The communication subsystem 104 receives messages from and sends messages
to a wireless network 150. The wireless network 150 may be any type of wireless network,
including, but not limited to, data wireless networks, voice wireless networks, and
networks that support both voice and data communications. A power source 142, such
as one or more rechargeable batteries or a port to an external power supply, powers
the electronic device 100.
[0013] The processor 102 interacts with other components, such as a Random Access Memory
(RAM) 108, memory 110, a touch-sensitive display 118, one or more actuators 120, one
or more force sensors 122, an auxiliary input/output (I/O) subsystem 124, a data port
126, a speaker 128, a microphone 130, short-range communications 132 and other device
subsystems 134, a keypad 137, a side key 139, etc. The touch-sensitive display 118
includes a display 112 and an overlay 114 that are coupled to at least one controller
116 that is utilized to interact with the processor 102. Input via a graphical user
interface is provided via the touch-sensitive display 118, the keypad apparatus 137
and/or the side key 139. Information, such as text, characters, symbols, images, icons,
and other items may be displayed or rendered on the touch-sensitive display 118 via
the processor 102. The processor 102 may also interact with an accelerometer 136 that
may be utilized to detect direction of gravitational forces or gravity-induced reaction
forces.
[0014] To identify a subscriber for network access, the electronic device 100 may utilize
a Subscriber Identity Module or a Removable User Identity Module (SIM/RUIM) card 138
for communication with a network, such as the wireless network 150. Alternatively,
user identification information may be programmed into memory 110.
[0015] The electronic device 100 includes an operating system 146 and software programs,
applications, or components 148 that are executed by the processor 102 and are typically
stored in a persistent, updatable store such as the memory 110. Additional applications
or programs may be loaded onto the portable electronic device 100 through the wireless
network 150, the auxiliary (I/O) subsystem 124, the data port 126, the short-range
communications subsystem 132, or any other device subsystems 134.
[0016] A received signal such as a text message, an e-mail message, or web page download
is processed by the communication subsystem 104 and input to the processor 102. The
processor 102 processes the received signal for output to the display 112 and/or to
the auxiliary (I/O) subsystem 124. A subscriber may generate data items, for example
e-mail messages, which may be transmitted over the wireless network 150 through the
communication subsystem 104. For voice communications, the overall operation of the
electronic device 100 is similar. The speaker 128 outputs audible information converted
from electrical signals, and the microphone 130 converts audible information into
electrical signals for processing.
[0017] The touch-sensitive display 118 may be any suitable touch-sensitive display, such
as a capacitive, resistive, infrared, surface acoustic wave (SAW) touch-sensitive
display, strain gauge, optical imaging, dispersive signal technology, acoustic pulse
recognition, and so forth. A capacitive touch-sensitive display includes one or more
capacitive touch sensors or overlay 114. The capacitive touch sensors may comprise
any suitable material, such as indium tin oxide (ITO). In other examples, the electronic
device 100 may include a non-touch sensitive display instead of, and/or in addition
to, the touch-sensitive display 118.
[0018] FIG. 2 is a plan view of a portable electronic device 200 having a keypad apparatus
or assembly 202 in accordance with the teachings disclosed herein. In the example
of FIG. 2, the portable electronic device 200 is a handheld or portable communication
device (e.g., a mobile phone). As mentioned above, the electronic device 200 may be
a data and/or voice-enabled handheld device that may be used to send and receive a
message, a voice communication, a textual entry, etc. Referring to FIG. 2, the electronic
device 200 includes a housing 204 that encloses electronic or mobile components such
as, for example, the electronic components described above in connection with FIG.
1. For example, the housing 204 encloses the keypad apparatus 202, a display 206,
a speaker 208, a microphone, an auxiliary I/O, a data port, etc. The housing 204 may
include a front cover or lid 210 that couples to a frame or base 212 to capture the
electronic components within the housing 204. The housing 204 of the illustrated example
can be held in one hand by a user of the electronic device 200 during data (e.g.,
text) and/or voice communications.
[0019] In the example of FIG. 2, the keypad apparatus 202 disclosed herein is positioned
on a side surface 214 of the electronic device 200. However, in some examples, the
keypad apparatus 202 may be positioned on another side surface and/or on multiple
side surfaces of the electronic device 200. (e.g., a top side surface, a bottom side
surface, side surfaces, etc.) The keypad apparatus 202 may include one or more buttons
or keys 216 that may be employed to input various commands to the electronic device.
For example, the keys 216 may be used to increase or decrease a volume of the electronic
device 200. In some examples, the keys 216 may be employed to zoom in and/or zoom
out when the electronic device 200 is in a camera mode. Additionally, the display
206 (e.g., a touch-screen display) may provide a keypad 218 to provide a user input
and accommodate textual inputs to the electronic device 200. The keypad 218 enables
character inputs including alphabetical and/or numeric entries to allow text and/or
numeric entry for various functions. For example, the keypad 218 may be a QWERTY style
keypad, a SureType keypad, or any other suitable physical keypad(s). Alternatively,
the keypad 218 may be a virtual keyboard that appears on a touch screen display (not
shown). In this example, the electronic device 200 also includes function keys 220.
For example, the function keys 220 may include an on/off button or call end button,
a call send button, a menu button, an escape key, etc. The electronic device 200 may
also include a track ball or trackpad 222 to input information and/or control commands.
[0020] A user interacts with the electronic device 200 via the keypad apparatus 202, the
keypad 218, the function keys 220 and/or the trackpad 222 to choose commands, execute
application programs, and perform other functions by selecting menu items or icons.
In combination with the keypad apparatus 202, a user may interact with the electronic
device 200 via the touch-sensitive display to choose commands, execute application
programs, and perform other functions by selecting menu items or icons by contacting
or touching the icon or image via the touch screen.
[0021] FIG. 3 illustrates an exploded view of an example electrical switch assembly 300
of the example keypad apparatus 202 of FIG. 2. The electrical switch assembly 300
is shown without the housing 204 of the electronic device 200. The electrical switch
assembly 300 of the illustrated example defines an electrical switch to couple to
a structure or circuit board 301 (e.g., a printed circuit board or integrated circuit
board). More specifically, in this example, the electrical switch assembly 300 defines
electrical switches 302a and 302b each associated with respective ones of the keys
216. However, in other examples, the electrical switch assembly 300 may include only
one electrical switch or more than two electrical switches.
[0022] The electrical switch assembly 300 of the illustrated example includes a dome-switch
assembly 304 coupled to a carrier 306. The dome-switch assembly 304 includes a housing
308, a dome 310 and a dome sheet 312. The housing 308 of the illustrated example includes
an opening or aperture 314 extending between a first surface 316 of the housing 308
and a second surface 318 of the housing 308 opposite the first surface 316. The aperture
314 of the housing 308 is configured or sized to receive at least a portion of the
dome 310. More specifically, at least a portion of the dome 310 is positioned in the
aperture 314 when the dome-switch assembly 304 is coupled to the carrier 306. The
dome 310 of FIG. 3 is a metal dome. The dome sheet 312 (e.g., a mylar film) retains
the dome 310 in the aperture 314 of the housing 308. The dome sheet 312 is coupled
or attached to a first surface 316 of the housing 308 via, for example, adhesive.
The housing 316 of the illustrated example couples the dome 310 to the carrier 306.
In the illustrated example, the dome-switch assembly 304 or the housing 308 is coupled
or attached to the carrier 306 via, for example, solder. As shown, the housing 308
includes one or more recesses, apertures or slots 320 positioned or formed on a side
surface 322 of the housing 308 to receive the solder to facilitate attachment or assembly
of the housing 308 to the carrier 306. However, in other examples, the housing 308
may be attached to the carrier 306 via adhesive and/or any other suitable chemical
fastener(s) and/or mechanical fastener(s).
[0023] The carrier 306 of the illustrated example comprises a body 324 having a plurality
of flexible fingers or arms 326. The body 324 and the flexible fingers 326 provide
a plurality of conductive trace patterns 328. More specifically, each of the trace
patterns 328 defines a first portion or conductive contacts 330 (e.g., electrical
contacts) and a second portion or conductive traces 332 (e.g., electrical traces).
In particular, the conductive contacts 330 are formed or provided on a first surface
334 (e.g., a side surface) of the carrier 306 and interact with the dome 310. The
conductive traces 332 couple the conductive contacts 330 to the circuit board 301.
As shown in the example of FIG. 3, a first set of electrical contacts 330a is electrically
coupled to the circuit board 301 via a first plurality of conductive traces 332a and
a second set of electrical contacts 330b is electrically coupled to the circuit board
301 via a second plurality of conductive traces 332b. The first and second plurality
of conductive traces 332a and 332b electrically isolate the first and second set of
electrical contacts 330a and 330b, respectively.
[0024] The body 324 of the carrier 306 of the illustrated example is a unitary structure
or body. The body 324, for example, is composed of a plastic material or plastic resin
such as, for example, a resin or plastic capable of being used in a Laser Direct Structuring
(LDS) process(es). For example, an LDS capable resin may include thermoplastic materials
such as, for example, Polypropylene, Polyethylene terephthalate, Polysulfone, etc.
The body 324 may be integrally formed via, for example, injection molding and/or any
other suitable manufacturing process(es). However, in some examples, the carrier 306
or the body 324 may be formed as multiple pieces (e.g., two-piece body) that may be
coupled together via chemical fasteners (e.g., adhesive), mechanical fasteners, plastic
welding, etc.
[0025] In the illustrated example, after the body 324 is formed via an injection molding
process, the electrical contacts 330 and/or the conductive traces 332 electrically
coupling the electrical contacts 330 to the circuit board 301 may be formed or etched
in the body 324 via, for example, LDS manufacturing process. Such a process enables
injection molded plastic parts such as the body 324 to be selectively plated with
discrete circuit pathways (i.e., the plurality of trace patterns 328). To this end,
a laser basically etches, writes or prints a conductive trace pattern corresponding
to the position of the conductive contacts 330 and/or the conductive traces 332 onto
the body 324 after the body 324 is formed via injection molding. The body 324 having
the printed pattern, contacts and/or traces is then immersed within a copper bath
to provide the conductive contacts 330, the conductive traces 332 and/or the trace
patterns 328.
[0026] FIG. 4 is a perspective view of the example electrical switch assembly 300 of FIG.
3 coupled to the circuit board 301. More specifically, the electrical switch assembly
300 is coupled to the circuit board 301 via frictional engagement or interference
fit. In this manner, the switch assembly 300 may be coupled to the circuit board 301
without the use of fasteners(s) (e.g., solder). However, in other examples, the electrical
switch assembly 300 may be coupled to the circuit board 301 via, for example, solder.
[0027] In the illustrated example, the electrical switch assembly 300 is electrically coupled
to a first or side surface 402 of the circuit board 301. As shown in FIG. 4, the side
surface 402 of the circuit board 301 is substantially parallel relative to the side
surface 214 of the housing 204 of FIG. 2. Thus, the side surface 402 of the circuit
board 301 of the illustrated example is substantially perpendicular to the second
surface 404 of the circuit board 301, which is substantially parallel or aligned with
the display 206 of the electronic device 200 of FIG. 2. As shown in FIG. 4, the side
surface 402 of the circuit board 301 has a surface area that is substantially less
than a surface area of the second surface 404. To enable the electrical switch assembly
300 to be electrically coupled to the side surface 402 of the circuit board 301, the
circuit board 301 includes one or more apertures or slots 406 (e.g., through holes)
plated with an electrically conductive material (e.g., copper). As shown in FIG. 4,
the plated slots 406 are exposed or accessible via the side surface 402 of the circuit
board 301. Each of the plated slots 406 defines a longitudinal axis and each of the
slots 406 extends between the second surface 404 and a third or bottom surface 408
of the circuit board 301. In some examples, the slots 406 partially extend between
the second surface 404 and the bottom surface 408.
[0028] FIG. 5A is a perspective bottom view of the electrical switch assembly 300 coupled
to the circuit board 301. FIG. 5B is a plan view of the example electrical switch
assembly 300 coupled to the circuit board 301. Referring to FIG. 5A and FIG. 5B, to
electrically couple the electrical contacts 330 to the circuit board 301, the conductive
traces 332 extend from the electrical contacts 330 to the conductive plated slots
406 of the circuit board 301. More specifically, the conductive traces 332 extend
from the first surface 334 of the carrier 306, an intermediate surface 502 (e.g.,
a curved bottom surface), a second surface 504 and along an outer surface 506 of the
flexible flingers 326. Thus, as shown in the illustrated example, a portion 508 of
the conductive traces 332 are printed, formed or provided on the outer surface 506
of the flexible fingers 326. The portion 508 of conductive traces 532 on the outer
surface 506 of the flexible fingers 326 electrically engage the plated slots 406 of
the circuit board 301 to electrically couple the electrical contacts 330 to the circuit
board 301. In other words, the conductive traces 332 and/or the electrical contacts
330 can be positioned and/or formed on any and/or all of the surfaces of the carrier
306 including, for example, the flexible fingers 326. The conductive traces 332 may
be configured on the carrier 306 in any pattern or surface to electrically couple
the electrical contacts 330 and the plated slots 406 of the circuit board 301.
[0029] Additionally, the flexible fingers 326 of the carrier 306 of the illustrated example
mechanically couple the carrier 306 to the circuit board 301 via frictional engagement
or interference. The flexible fingers 326 provide a spring bias or force 510 to retain
the carrier 306 engaged with the plated slots 406 of the circuit board 301. For example,
each of the flexible fingers 326 provide a reactive force 510 in a direction normal
to the longitudinal axes of the plated slots 406 and/or the side surface 402 of the
circuit board 301. As clearly shown in FIG. 5B, the carrier 306 can be positioned
adjacent the side surface 402 of the circuit board 301 with relatively small clearance
or distance 512. As a result, the closer the flexible fingers 326 bend, flex and/or
move toward the second side 504 of the carrier 306, the greater the force 510 the
flexible fingers 326 impart to the plated slots 406 of the circuit board 301 to retain
the carrier 306 coupled or positioned relative to the plated slots 406 and/or the
circuit board 301. Thus, the flexible fingers 326 provide the force 510 to retain
the carrier 306 coupled to the circuit board 301 when the electrical switch assembly
300 is positioned between the housing 204 of the electronic device 200 of FIG. 2 and
the circuit board 301. Thus, the carrier 306 does not require solder, adhesive and/or
other fasteners to couple to the circuit board 301. Instead, the flexible fingers
326 prevent the carrier 306 from moving or shifting laterally relative to and/or along
the side surface 402 of the circuit board 301. Accordingly, because solder is not
needed to couple the carrier 306 to the circuit board 301, the dimensional envelope
of the electrical switch assembly 300 is significantly smaller. As a result, the electrical
switch assembly 300 and/or carrier 306 enable the electronic device 200 to have a
substantially smaller dimensional envelope or profile (e.g., a dimensional height).
Additionally or alternatively, because chemical or mechanical fasteners are not needed
to couple the electrical switch assembly 300 to the circuit board 301, the electrical
switch assembly 300 significantly facilitates assembly of the electronic device 200
of FIG. 2.
[0030] FIG. 6 is a cross-sectional side view of the example electrical switch assembly 302
of FIGS. 2-4, 5A and 5B taken along line 6-6 of FIG. 4. As shown in FIG. 6, the electrical
switch assembly 300 is positioned between a side wall 602 of the housing 204 or base
212 of the electronic device 200 and the circuit board 301. The keypad apparatus 202
of the illustrated example includes an actuator assembly 604 positioned adjacent the
electrical switch assembly 300. The actuator assembly 604 interacts with the electrical
switch assembly 300 to generate an electrical signal when a user depresses the keys
216 associated or corresponding to the electrical switches 302a or 302b. The actuator
assembly 604 of the illustrated example includes the key 216 (e.g., a button) and
a plunger or actuator 606 positioned between the key 216 and the dome 310. The actuator
606 provides stiffness to hold the key 216 in position when a force is not exerted
on the key 216 toward the dome 310. In this example, the key 216 at least partially
extends from the housing 204 when the key 216 is not depressed as shown in FIG. 6.
[0031] The dome 310 is positioned adjacent the electrical elements 330 of the carrier 306
and is aligned relative to the conductive contacts 330 of the respective trace patterns
328. As shown, the dome 310 is positioned inside the aperture 314 of the housing 308
such that the dome 310 can engage the first surface 334 of the carrier 306. More specifically,
the aperture 314 enables the dome 310 to engage the electrical contacts 330 when the
dome 310 is deflected or collapsed. As shown, the dome sheet 312 retains the dome
310 in the aperture 314 of the housing 308.
[0032] In operation, the actuator 606 provides stiffness to hold the key 216 in position.
Further, the dome-switch assemblies 304 are in a non-deflected or non-collapsed position
when the key 216 is not pressed or actuated. A user can exert a force (e.g., a side
force) on the key 216 to depress the key 216 associated with the electrical switch
302a with relative ease. The force required to press the key 216 is large enough that
the person can feel a resistance to the pressure of their finger on the key 216. The
electronic device 200 detects or senses a deflection or activation of the electrical
switch when the key 216 is in a depressed position or actuated position relative to
the base 212 to activate the electrical switch and generate an electrical signal.
[0033] For example, to activate the electrical switch 302a, a user depresses the key 216
associated with the electrical switch 302a to provide data input to the electronic
device 200. In particular, the electrical switch 302a generates an output signal that
is received by a processor (e.g., the processor 102) when the key 216 is depressed
by a user. When a user presses the key 216, the actuator 606 moves toward the trace
pattern 328 of the carrier 306. The actuator 606 presses against the dome 310 to cause
the dome 310 to deflect, collapse, flex or bend toward the trace pattern 328 of the
carrier 306. In turn, the dome 310 collapses toward the conductive contacts 330 of
the trace pattern 328 such that a contact surface 610 of the dome 310 engages the
conductive contacts 330 of the carrier 306, thereby closing an electrical circuit
and generating an electrical signal that is received or detected by the processor
102. The dome 310 is configured to provide a dome-snap profile to provide a click
(e.g., an audible sound) or snap feel tactility to a user.
[0034] To return the key 216 to the non-actuated or initial position in which the electrical
switch is deactivated, a user releases the key 216. When the key 216 is released,
the actuator 606 returns to its original position or state and releases the dome 310.
The dome 310 also snaps back to its initial, original or dome shaped position. The
dome 310 provides a tactile feedback (e.g., a force) to the user when the dome 310
snaps back to its original position. In particular, the dome 310 functions as a spring
to push the actuator 606 back to the initial or non-activated position as shown in
FIG. 6.
[0035] Although not shown, in other examples, the switch assembly 300 can be configured
without use of the dome-switch assembly 304. For example, the actuator 606 may employ
a conductive material or element to interact with the conductive contacts 330 of the
carrier 306. For example, the actuator 606 may be biased away from the first surface
334 of the carrier 306 via a biasing element.
[0036] FIG. 7 illustrates another example keypad apparatus 700 constructed in accordance
with the teachings disclosed herein. Unlike the example keypad apparatus 202 of FIGS.
2-4, 5A, 5B and 6, an electrical switch assembly 702 of the example keypad apparatus
700 of FIG. 7 does not employ a housing (e.g., the housing 306 of the dome-switch
assembly 304). Instead, a carrier 704 is formed with a recess or cavity 706 to receive
at least a portion of a dome 708. A dome-sheet 710 is attached to a surface 712 of
the carrier 704 to retain the dome 708 in the cavity 706. A surface or wall 714 defined
by the cavity 706 includes a trace pattern 716. The trace patterns 716 include conductive
contacts 718 that are routed to a circuit board 720 via conductive traces 722 formed
on surface 724, the surface 714 and/or a flexible finger 726 of the carrier 704 in
a manner similar to the trace patterns 328 of FIGS. 2-4, 5A, 5B and 6. The carrier
704 is formed via injection molding and the conductive contacts 718 and/or the traces
722 may be formed on the carrier 704 via, for example, LDS manufacturing process.
As shown, because the carrier 704 may be formed via injection molding, the example
carrier 704 is formed with the cavity 706 sized or configured to receive the dome
708.
[0037] FIG. 8 illustrates another example electrical switch assembly 800 disclosed herein.
The electrical switch assembly 800 of FIG. 8 is coupled to a first surface 802 of
a circuit board 804. In this example, the electrical switch assembly 800 is mounted
on the first surface 802 of the circuit board 804 via soldering. However, in other
examples, the switch assembly 800 may be coupled to the circuit board 804 via any
other suitable chemical fastener(s) (e.g., adhesive) and/or mechanical fastener(s).
[0038] FIG. 9 is an exploded view of the example electrical switch assembly 800 of FIG.
8. The electrical switch assembly 800 employs a dome-switch assembly 902 coupled to
a carrier 904 (e.g., via solder or an adhesive). The dome-switch assembly 902 includes
a housing 906, a dome 908 and a dome-sheet 910. The housing 906 includes an opening
912 to receive the dome 908. The dome-sheet 910 is coupled to the housing 906 to retain
the dome 908 in the opening 912 of the housing 906.
[0039] The carrier 904 of the illustrated example defines a body 914 having a first portion
or leg 916 and a second portion or leg 918. More specifically, as shown, the body
914 defines an L-shaped body or profile such that the first portion 916 is substantially
perpendicular relative to the second portion 918. In addition, the carrier 904 provides
or defines a conductive trace pattern 920. More specifically, the conductive trace
pattern 920 defines an electrical contact or conductive element 922 formed or provided
on a first surface 924 (e.g., a side surface) of the first portion 916 that interact
with the dome 908. The electrical contacts 922 are electrically coupled to the circuit
board 804 via conductive traces 926. The conductive traces 926 extend from the first
surface 924 of the first portion 916 across a second surface 928 of the second portion
918.
[0040] FIG. 10 is another perspective view of the example electrical switch 800 of FIGS.
8 and 9. Referring to FIGS. 8-10, the conductive traces 926 extend to a third surface
1002 of the second portion 918 of the carrier 904. The traces 926 formed on the third
surface 1002 engage electrical contacts or traces positioned on the surface 802 of
the circuit board 804, when the carrier 904 is coupled to the circuit board 804, to
electrically couple the electrical contacts 922 and the circuit board 804. In other
examples, the traces 926 may extend across any other surface(s) of the carrier 904.
For example, the traces 926 may extend across the first surface 924 of the first portion
916 and a fourth surface 1004 of the first portion 916 to electrically engage electrical
contacts on a side surface (e.g., perpendicular to surface 802) of the circuit board
804. Alternatively, the traces 926 can extend from the fourth surface 1004 of the
first portion 916 to the third surface 1002 of the second portion 918. The carrier
904 may be coupled to the surface 802 of the circuit board 804 via, for example, solder
1006.
[0041] The carrier 904 of the illustrated example is a unitary structure or body. The carrier
904, for example, is composed of a plastic material or resin such as, for example,
a Laser Direct Structuring (LDS) resin. The carrier 904 may be integrally formed via,
for example, injection molding and/or any other suitable manufacturing process(es).
In the illustrated example, after the carrier 904 is formed via an injection molding
process, the electrical contacts 922 and/or the electrical traces 926 electrically
coupling the electrical contacts 922 to the circuit board 804 may be formed or etched
in the carrier 904 via, for example, the LDS manufacturing process described above.
[0042] FIG. 11 illustrates the example switch assembly 800 of FIGS. 8-10 coupled to another
example circuit board 1102. In this example, the circuit board 1102 enables the switch
assembly 800 to be substantially flush-mounted relative to a surface 1104 of the circuit
board 1102 (e.g., a surface substantially parallel to a display of an electronic device).
In this example, the surface 1104 of the circuit board 1102 is substantially perpendicular
to a side surface 1106 of the circuit board 1102. The circuit board 1102 includes
a recess 1108 to receive a portion of the carrier 904. More specifically, the recess
1108 receives the second portion 918 of the carrier 904. The third surface 1002 (FIG.
10) of the carrier 904 engages a surface or base defined by the recess 1108 such that
the traces 926 engage respective electrical contacts positioned on the base of the
recess 1108. When coupled to the circuit board 1102, walls 1110 of the circuit board
1102 defined by the recess 1108 maintain or hold a portion and/or position (e.g.,
a lateral position) of the carrier 904 relative to the side surface 1106 of the circuit
board 1102. Thus, the example electrical switch assembly 800 of FIG. 11 may be coupled
to the circuit board 1102 without a mechanical fastener(s) (e.g., solder) or chemical
fastener(s). The example switch assembly 800 and circuit board 1102 of FIG. 11 enables
an electronic device (e.g., the electronic device 200) employing the electrical switch
assembly 800 and the circuit board 1102 to have a relatively smaller profile or dimensional
envelope compared to the switch assembly 800 mounted to the circuit board 804.
[0043] Fig. 12 is a flowchart of an example method 1200 that may be used to manufacture
an example switch assembly such as the example switch assemblies 300, 702 and 800
disclosed herein. While an example manner of manufacturing the example switch assembly,
one or more of the blocks and/or processes illustrated in FIG. 12 may be combined,
divided, re-arranged, omitted, eliminated and/or implemented in any other way. Further
still, the example method of FIG. 12 may include one or more processes and/or blocks
in addition to, or instead of, those illustrated in FIG. 12, and/or may include more
than one of any or all of the illustrated processes and/or blocks. Further, although
the example method 1200 is described with reference to the flow chart illustrated
in FIG. 12, many other methods of manufacturing a covering assembly may alternatively
be used.
[0044] To begin the example assembly process of FIG. 12, a carrier (e.g., the carrier 306)
is formed or provided (block 1202). For example, the carrier may be composed of plastic
and may be formed via injection molding. More specifically, the carrier may be formed
via a resin (e.g., a thermoplastic material) capable of being used in a laser direct
structuring process.
[0045] After the carrier is formed, a conductive pattern (e.g., the pattern 328) is printed
or formed on one or more surfaces of the carrier (block 1204). For example, the carrier
may include one or more conductive contacts or elements and one or more conductive
traces or paths to electrically couple the conductive contacts to a circuit board.
For example, the conductive pattern may be formed on any surface, wall or area of
the carrier via the Laser Direct Structuring method. After the carrier is formed,
an actuator or dome-switch assembly (e.g., the dome-switch assembly 304) is coupled
to the carrier.
[0046] The carrier is then coupled to a printed circuit board (block 1206). More specifically,
a portion of the conductive pattern is to engage a conductive element (e.g., the plated
slots 406) of a circuit board. For example, a conductive contact may be formed on
a first surface of the carrier and a conductive trace may extend from the first surface
(e.g., a front surface) to a second surface (e.g., a rear surface) opposite the first
surface to engage an electrical contact of a circuit board. In some examples, the
carrier employs flexible fingers or arms (e.g., the flexible fingers 326) that engage
plated slots or openings of the circuit board.
[0047] The example switch assemblies 300, 702 and 800 disclosed herein significantly facilitate
assembly of a keypad apparatus to a circuit board. For example, the example electrical
switch assemblies 300, 702 and 800 may be coupled to a circuit board via friction
fit without the use of fasteners (e.g., chemical fasteners, mechanical fasteners,
solder, etc.). In this manner, for example, the example switch assemblies 300, 702
and 800 disclosed herein reduce cost associated with soldering the switch assemblies
300, 702 and 800 to a circuit board. Additionally or alternatively, the example switch
assemblies 300, 702 and 800 disclosed herein may be side mounted and/or flush mounted
relative to a circuit board to reduce an overall dimensional profile (e.g., a height
or width) of an electronic device.
[0048] The methods described herein may be carried out by software executed, for example,
by the processor 102. Coding of software for carrying out such a method is within
the scope of a person of ordinary skill in the art given the present description.
A computer-readable medium having computer-readable code may be executed by at least
one processor of the portable electronic device 100 to perform the methods described
herein.
[0049] The scope of the disclosure is defined by the appended claims.