U.S. patent application number 14/555642 was filed with the patent office on 2016-06-02 for voice coil protection using damping.
The applicant listed for this patent is BLACKBERRY LIMITED. Invention is credited to Isao Ginn ANAZAWA.
Application Number | 20160156322 14/555642 |
Document ID | / |
Family ID | 54608321 |
Filed Date | 2016-06-02 |
United States Patent
Application |
20160156322 |
Kind Code |
A1 |
ANAZAWA; Isao Ginn |
June 2, 2016 |
VOICE COIL PROTECTION USING DAMPING
Abstract
A method, system and apparatus for voice coil protection using
damping are provided. At a device and/or a system comprising: a
processor; a sound transducer comprising a voice coil; a power
supply; an amplifier in communication with the voice coil; and a
circuit configured to apply an electromotive force ("EMF") to the
voice coil under control of the processor, the amplifier is placed
into a standby state. When the amplifier is in the standby state,
the circuit is controlled to apply the EMF to the voice coil using
the power supply so that the voice coil has restricted
excursion.
Inventors: |
ANAZAWA; Isao Ginn;
(Kitchener, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BLACKBERRY LIMITED |
Waterloo |
|
CA |
|
|
Family ID: |
54608321 |
Appl. No.: |
14/555642 |
Filed: |
November 27, 2014 |
Current U.S.
Class: |
381/55 |
Current CPC
Class: |
H03G 1/0035 20130101;
H04R 3/007 20130101; H04R 2499/11 20130101; H04R 29/003
20130101 |
International
Class: |
H03G 1/00 20060101
H03G001/00; H04R 3/00 20060101 H04R003/00 |
Claims
1. A device comprising: a processor; a sound transducer comprising
a voice coil; a power supply; an amplifier in communication with
the voice coil; and a circuit configured to apply an electromotive
force ("EMF") to the voice coil under control of the processor; the
processor configured to: place the amplifier into a standby state;
and, when the amplifier is in the standby state, control the
circuit to apply the EMF to the voice coil using the power supply
so that the voice coil has restricted excursion.
2. The device of claim 1, wherein the circuit comprises a portion
of the amplifier.
3. The device of claim 1, wherein the circuit comprises electrical
components configured to apply the EMF to the voice coil in the
standby state.
4. The device of claim 1, wherein the circuit comprises a
resistance such that the voice coil is terminated in the
resistance, which is in turn in communication with the power
supply, when the amplifier is in the standby state, the voice coil
being otherwise controlled by the amplifier.
5. The device of claim 1, wherein the circuit comprises two
transistors in series with the voice coil and a connection to the
power supply located between the two transistors, the processor
further configured to turn the two transistors on when the
amplifier is in the standby state.
6. The device of claim 5, wherein the amplifier comprises the two
transistors, the two transistors used to drive the voice coil to
emit sound when the amplifier is not in the standby state.
7. The device of claim 1, further comprising a sensor and one or
more switches configured to connect the voice coil with the sensor
when the one or more switches are closed, the sensor configured to
detect an output from the voice coil, the processor further
configured to: close the one or more switches when the amplifier is
in the standby state, and otherwise open the one or more switches;
and, when the amplifier is in the standby state, and when the
output of the voice coil, as detected by the sensor, is above a
threshold value, control the circuit to apply the EMF to the voice
coil using the power supply.
8. The device of claim 7, wherein the sensor comprises a diode.
9. The device of claim 1, further comprising a sensor configured to
detect an output EMF from the voice coil, the circuit further
configured to apply the EMF to the voice coil, the EMF being about
similar to the output EMF but in an opposite direction.
10. The device of claim 1, further comprising an accelerometer, the
processor further configured to, when the amplifier is in the
standby state, and when output from the accelerometer is above a
threshold value, control the circuit to apply the EMF to the voice
coil.
11. The device of claim 1, wherein the sound transducer comprises a
loudspeaker.
12. The device of claim 1, wherein the sound transducer comprises
one or more of a receiver and a microphone.
13. The device of claim 1, wherein the processor is further
configured to place the amplifier in the standby state by turning
off components of the amplifier other than those related to the
circuit.
14. A method comprising: placing, using a processor of a device, an
amplifier of the device into a standby state, the device
comprising: the processor; a sound transducer comprising a voice
coil; a power supply; the amplifier in communication with the voice
coil; and a circuit configured to apply an electromotive force
("EMF") to the voice coil under control of the processor; and, when
the amplifier is in the standby state, controlling, using the
processor, the circuit to apply the EMF to the voice coil using the
power supply so that the voice coil has restricted excursion.
15. The method of claim 14, wherein the device further comprises a
sensor and one or more switches configured to connect the voice
coil with the sensor when the one or more switches are closed, the
sensor configured to detect an output from the voice coil, the
method further comprising: closing, using the processor, the one or
more switches when the amplifier is in the standby state, and
otherwise opening, using the processor, the one or more switches;
and, when the amplifier is in the standby state, and when the
output of the voice coil, as detected by the sensor, is above a
threshold value, control the circuit to apply the EMF to the voice
coil using the power supply.
16. The method of claim 14, wherein the device further comprises a
sensor configured to detect an output EMF from the voice coil, the
method further comprising applying, using the circuit, the EMF to
the voice coil, the EMF being about similar to the output EMF but
in an opposite direction.
17. The method of claim 14, wherein the device further comprises an
accelerometer, the method further comprising, when the amplifier is
in the standby state, and when output from the accelerometer is
above a threshold value, controlling, using the processor, the
circuit to apply the EMF to the voice coil.
18. The method of claim 14, further comprising, placing, using the
processor, the amplifier in the standby state by turning off
components of the amplifier other than those related to the
circuit.
19. A computer program product, comprising a non-transitory
computer usable medium having a computer readable program code
adapted to be executed to implement a method comprising: placing,
using a processor of a device, an amplifier of the device into a
standby state, the device comprising: the processor; a sound
transducer comprising a voice coil; a power supply; the amplifier
in communication with the voice coil; and a circuit configured to
apply an electromotive force ("EMF") to the voice coil under
control of the processor; and, when the amplifier is in the standby
state, controlling, using the processor, the circuit to apply the
EMF to the voice coil using the power supply so that the voice coil
has restricted excursion.
Description
FIELD
[0001] The specification relates generally to sound transducers,
and specifically to a method, system and apparatus for voice coil
protection using damping.
BACKGROUND
[0002] Moving parts of a sound transducer, for example a
loudspeaker and/or a receiver, include a membrane/voice-coil
assembly which, in the case of a loudspeaker, is driven by an
amplifier to produce sound based on an input signal and, in the
case of a receiver has output voltage and/or current amplified by
an amplifier. Excess amounts of voice coil and/or membrane
excursion can be limited by a damping factor of the amplifier
during operation, which generally has low impedance relative to the
voice coil. While the amplifier is in a standby state and/or
disabled state, the output impedance of the amplifier becomes high.
This is problematic, and can become a serious concern, when the
sound transducer is dropped on a hard floor and/or exposed to high
acceleration of a force as, in this configuration, the
membrane/voice-coil assembly is free to move. Hence, an excess
amount of the voice coil excursion can result which, in a worst
case scenario, results in the membrane/voice-coil assembly being
damaged permanently.
BRIEF DESCRIPTIONS OF THE DRAWINGS
[0003] For a better understanding of the various implementations
described herein and to show more clearly how they may be carried
into effect, reference will now be made, by way of example only, to
the accompanying drawings in which:
[0004] FIG. 1 depicts a device configured for voice coil protection
using damping, according to non-limiting implementations.
[0005] FIG. 2 depicts a schematic block diagram of the device of
FIG. 1, according to non-limiting implementations.
[0006] FIG. 3 depicts a method of voice coil protection using
damping, according to non-limiting implementations.
[0007] FIG. 4 depicts details of components of the device of FIG. 1
for voice coil protection using damping, according to non-limiting
implementations.
[0008] FIG. 5 depicts an equivalent circuit of the components of
FIG. 4, according to non-limiting implementations.
[0009] FIG. 6 depicts another equivalent circuit of the components
of FIG. 4, as well as equations for modelling the another
equivalent circuit, according to non-limiting implementations.
[0010] FIG. 7 depicts details of components of the device of FIG. 1
for voice coil protection using damping, according to alternative
non-limiting implementations.
[0011] FIG. 8 depicts details of components of the device of FIG. 1
for voice coil protection using damping, according to other
alternative non-limiting implementations.
[0012] FIG. 9 depicts details of components of the device of FIG. 1
for voice coil protection using damping, according to yet further
alternative non-limiting implementations.
DETAILED DESCRIPTION
[0013] In general, this disclosure is directed to a device that
includes sound transducer and/or voice coil protection using
damping. In particular, the device includes a circuit which applies
an electromotive force to a voice coil of the sound transducer when
an amplifier, that otherwise assists in operation of the voice
coil, is placed in a standby mode, where components of the
amplifier are placed in an off-state and/or low power state. The
circuit can be implemented in various ways, however in each case
the voice coil terminates in a resistance when the amplifier is in
the standby mode, the resistance being in communication to a power
supply of the device, the resistance being small enough so that an
electromotive force is applied to the voice coil that prevents
and/or minimizes excursion of the voice coil, and/or a membrane of
the sound transducer. In one implementation, the circuit includes a
portion of the amplifier, and in particular two transistors which
can be controlled to apply the electromotive force by placing them
in a closed state, with other transistors of the amplifier placed
in an open state. In other implementations, the circuit and/or the
two transistors can be separate from the amplifier. In yet further
implementations, the device can include a sensor that can detect
output of the voice coil and/or excursion of the device, and the
electromotive force applied either according to the output and/or
when excursion is detected, and when the amplifier is in the
standby mode.
[0014] In this specification, the term "loudspeaker", "speaker" and
"microspeaker" will be used interchangeably, and while present
implementations are described with respect to loudspeakers at a
mobile device, present implementations can be applied to any device
in which loudspeaker excursion is to be limited to avoid damage.
Specifically, it is appreciated that the terms "loudspeaker"
"speaker" and "microspeaker" each refer to hardware which is used
to provide sound at a device by using a voltage representing sound
data to drive a voice coil at the loudspeaker. Furthermore, while
the present specification refers to a voice coil at a loudspeaker,
it is appreciated that the term voice coil is used interchangeably
with the term speaker coil, and that a voice coil is used to
convert voltages to sound, including, but not limited to sound from
voice data, music data, video data, and the like. In other words,
while voice coils described herein can be used to produce sound
that corresponds to the voice of a human, and the like, voice coils
described herein are not to be limited to such implementations.
[0015] Reference may also be made herein to the term "program
material" which can comprises sound data used to drive a
loudspeaker including, but not limited to, voice data, music data,
video data, and the like. In other words, "program material" as
used herein can refer to sound data and/or sound files which can be
processed to produce an input signal to a loudspeaker. In some
instances, the term "program material", however, will be used
colloquially and interchangeably with the terms input signal and
output signal, signifying that the program material is used to
produce an input signal to a loudspeaker and/or an output signal
that drives the loudspeaker, the output signal comprising a
filtered version of the input signal.
[0016] In this specification, elements may be described as
"configured to" perform one or more functions or "configured for"
such functions. In general, an element that is configured to
perform or configured for performing a function is enabled to
perform the function, or is suitable for performing the function,
or is adapted to perform the function, or is operable to perform
the function, or is otherwise capable of performing the
function.
[0017] It is understood that for the purpose of this specification,
language of "at least one of X, Y, and Z" and "one or more of X, Y
and Z" can be construed as X only, Y only, Z only, or any
combination of two or more items X, Y, and Z (e.g., XYZ, XY, YZ,
ZZ, and the like). Similar logic can be applied for two or more
items in any occurrence of "at least one . . . " and "one or more .
. . " language.
[0018] An aspect of the specification provides a device comprising:
a processor; a sound transducer comprising a voice coil; a power
supply; an amplifier in communication with the voice coil; and a
circuit configured to apply an electromotive force ("EMF") to the
voice coil under control of the processor; the processor configured
to: place the amplifier into a standby state; and, when the
amplifier is in the standby state, control the circuit to apply the
EMF to the voice coil using the power supply so that the voice coil
has restricted excursion.
[0019] The circuit can comprise a portion of the amplifier.
[0020] The circuit can comprise electrical components configured to
apply the EMF to the voice coil in the standby state.
[0021] The circuit can comprise a resistance such that the voice
coil is terminated in the resistance, which is in turn in
communication with the power supply, when the amplifier is in the
standby state, the voice coil being otherwise controlled by the
amplifier.
[0022] The circuit can comprise two transistors in series with the
voice coil and a connection to the power supply located between the
two transistors, the processor can be further configured to turn
the two transistors on when the amplifier is in the standby state.
The amplifier can comprise the two transistors, the two transistors
used to drive the voice coil to emit sound when the amplifier is
not in the standby state.
[0023] The device can further comprise a sensor and one or more
switches configured to connect the voice coil with the sensor when
the one or more switches are closed, the sensor configured to
detect an output from the voice coil, the processor can be further
configured to: close the one or more switches when the amplifier is
in the standby state, and otherwise open the one or more switches;
and, when the amplifier is in the standby state, and when the
output of the voice coil, as detected by the sensor, is above a
threshold value, control the circuit to apply the EMF to the voice
coil using the power supply. The sensor can comprise a diode.
[0024] The device can further comprise a sensor configured to
detect an output EMF from the voice coil, the circuit further
configured to apply the EMF to the voice coil, the EMF being about
similar to the output EMF but in an opposite direction.
[0025] The device can further comprise an accelerometer, the
processor can be further configured to, when the amplifier is in
the standby state, and when output from the accelerometer is above
a threshold value, control the circuit to apply the EMF to the
voice coil.
[0026] The sound transducer can comprise a loudspeaker.
[0027] The sound transducer can comprise one or more of a receiver
and a microphone.
[0028] The processor can be further configured to place the
amplifier in the standby state by turning off components of the
amplifier other than those related to the circuit.
[0029] Another aspect of the specification provides a method
comprising: placing, using a processor of a device, an amplifier of
the device into a standby state, the device comprising: the
processor; a sound transducer comprising a voice coil; a power
supply; the amplifier in communication with the voice coil; and a
circuit configured to apply an electromotive force ("EMF") to the
voice coil under control of the processor; and, when the amplifier
is in the standby state, controlling, using the processor, the
circuit to apply the EMF to the voice coil using the power supply
so that the voice coil has restricted excursion.
[0030] The device further can comprise a sensor and one or more
switches configured to connect the voice coil with the sensor when
the one or more switches are closed, the sensor configured to
detect an output from the voice coil, and the method can further
comprise: closing, using the processor, the one or more switches
when the amplifier is in the standby state, and otherwise opening,
using the processor, the one or more switches; and, when the
amplifier is in the standby state, and when the output of the voice
coil, as detected by the sensor, is above a threshold value,
control the circuit to apply the EMF to the voice coil using the
power supply.
[0031] The device further can comprise a sensor configured to
detect an output EMF from the voice coil, and the method can
further comprise applying, using the circuit, the EMF to the voice
coil, the EMF being about similar to the output EMF but in an
opposite direction.
[0032] The device further can comprise an accelerometer, and the
method can further comprise, when the amplifier is in the standby
state, and when output from the accelerometer is above a threshold
value, controlling, using the processor, the circuit to apply the
EMF to the voice coil.
[0033] The method can further comprise, placing, using the
processor, the amplifier in the standby state by turning off
components of the amplifier other than those related to the
circuit.
[0034] Yet a further aspect of the specification provides a
computer program product, comprising a computer usable medium
having a computer readable program code adapted to be executed to
implement a method comprising: placing, using a processor of a
device, an amplifier of the device into a standby state, the device
comprising: the processor; a sound transducer comprising a voice
coil; a power supply; the amplifier in communication with the voice
coil; and a circuit configured to apply an electromotive force
("EMF") to the voice coil under control of the processor; and, when
the amplifier is in the standby state, controlling, using the
processor, the circuit to apply the EMF to the voice coil using the
power supply so that the voice coil has restricted excursion. The
computer usable medium can comprise a non-transitory computer
usable medium.
[0035] Attention is next directed to FIG. 1 and FIG. 2 which
respectively depict a front perspective view and a schematic
diagram of a mobile electronic device 101, referred to
interchangeably hereafter as device 101, according to non-limiting
implementations. Device 101 is generally configured for loudspeaker
and receiver transducer protection using damping, as will be
explained in detail hereafter. Device 101 comprises: a processor
120; a sound transducer 132 comprising a voice coil 135; a power
supply 136; an amplifier 137 in communication with voice coil 135;
and a circuit 138 configured to apply an electromotive force
("EMF") to voice coil 135 under control of processor 120; processor
120 configured to: place amplifier 137 into a standby state; and,
when amplifier 137 is in the standby state, control circuit 138 to
apply the EMF to voice coil 135 using power supply 136 so that
voice coil 135 has restricted excursion. While optional, device 101
further comprises a communication interface 124 (interchangeably
referred to hereafter as interface 124) and an input device 128.
Furthermore, sound transducer 132 can comprise a loudspeaker or a
microphone.
[0036] Device 101 can be any type of electronic device that can be
used in a self-contained manner to communicate with one or more
communication networks. Device 101 can include, but is not limited
to, any suitable combination of electronic devices, communications
devices, computing devices, personal computers, laptop computers,
portable electronic devices, mobile computing devices, portable
computing devices, tablet computing devices, laptop computing
devices, desktop phones, telephones, PDAs (personal digital
assistants), cellphones, smartphones, e-readers, internet-enabled
appliances and the like. Other suitable devices are within the
scope of present implementations. For example, device 101 need not
comprise a mobile communication device, but rather can comprise a
loudspeaker system and/or a receiver system with associated
specialized functions, and being connectable to stereo systems,
recording systems, and the like.
[0037] It should be emphasized that the shape and structure of
device 101 in FIGS. 1 and 2 are purely examples, and contemplate a
device that can be used for both wireless voice (e.g. telephony)
and wireless data communications (e.g. email, web browsing, text,
and the like). However, FIG. 1 contemplates a device that can be
used for any suitable specialized functions, including, but not
limited, to one or more of, telephony, computing, appliance, and/or
entertainment related functions. In other words, in other
implementations, device 101 can comprise any device that comprises
one or more loudspeakers that converts sound data to sound,
including, but not limited to, a television, a stereo system, an
entertainment device, and the like.
[0038] With reference to FIGS. 1 and 2, device 101 comprises at
least one input device 128 generally configured to receive input
data, and can comprise any suitable combination of input devices,
including but not limited to a keyboard, a keypad, a pointing
device (as depicted in FIG. 1), a mouse, a track wheel, a
trackball, a touchpad, a touch screen and the like. Other suitable
input devices are within the scope of present implementations.
[0039] Input from input device 128 is received at processor 120 (f
which can be implemented as a plurality of processors, and/or as
one or more DSPs including but not limited to one or more central
processors (CPUs)). Processor 120 is configured to communicate with
a memory 122 comprising a non-volatile storage unit (e.g. Erasable
Electronic Programmable Read Only Memory ("EEPROM"), Flash Memory)
and a volatile storage unit (e.g. random access memory ("RAM")).
Programming instructions that implement the functional teachings of
device 101 as described herein are typically maintained,
persistently, in memory 122 and used by processor 120 which makes
appropriate utilization of volatile storage during the execution of
such programming instructions. Those skilled in the art will now
recognize that memory 122 is an example of computer readable media
that can store programming instructions executable on processor
120. Furthermore, memory 122 is also an example of a memory unit
and/or memory module.
[0040] Memory 122 further stores an application 146 that, when
processed by processor 120, enables processor 120 to: place
amplifier 137 into a standby state; and, when amplifier 137 is in
the standby state, control circuit 138 to apply the EMF to voice
coil 135 using power supply 136 so that voice coil 135 has
restricted excursion.
[0041] Furthermore, memory 122 storing application 146 is an
example of a computer program product, comprising a non-transitory
computer usable medium having a computer readable program code
adapted to be executed to implement a method, for example a method
stored in application 146.
[0042] Processor 120 can be further configured to communicate with
display 126, which comprises any suitable one of, or combination
of, flat panel displays (e.g. LCD (liquid crystal display), plasma
displays, OLED (organic light emitting diode) displays, capacitive
or resistive touchscreens, CRTs (cathode ray tubes) and the
like.
[0043] Processor 120 also connects to communication interface 124
(interchangeably referred to interchangeably as interface 124),
which can be implemented as one or more radios and/or connectors
and/or network adaptors, configured to wirelessly communicate with
one or more communication networks (not depicted). It will be
appreciated that interface 124 is configured to correspond with
network architecture that is used to implement one or more
communication links to the one or more communication networks,
including but not limited to any suitable combination of USB
(universal serial bus) cables, serial cables, wireless links,
cell-phone links, cellular network links (including but not limited
to 2G, 2.5G, 3G, 4G+ such as UMTS (Universal Mobile
Telecommunications System), GSM (Global System for Mobile
Communications), CDMA (Code division multiple access), FDD
(frequency division duplexing), LTE (Long Term Evolution), TDD
(time division duplexing), TDD-LTE (TDD-Long Term Evolution),
TD-SCDMA (Time Division Synchronous Code Division Multiple Access)
and the like, wireless data, Bluetooth links, NFC (near field
communication) links, WLAN (wireless local area network) links,
WiFi links, WiMax links, packet based links, the Internet, analog
networks, the PSTN (public switched telephone network), access
points, and the like, and/or a combination.
[0044] Power supply 136 can comprise, a battery, a power pack and
the like; however, in other implementations, power supply 136 can
comprise a connection to a mains power supply and/or a power
adaptor (e.g. and AC-to-DC (alternating current to direct current)
adaptor). Furthermore, power supply 136 powers components of device
101 including, but not limited to processor 120, amplifier 137,
circuit 138, sound transducer 132, voice coil 135 and the like.
[0045] Sound transducer 132, and voice coil 135, can comprise any
sound transducer system configured to either emit sound under
control of amplifier 137 (when sound transducer 132 comprises a
loudspeaker) or amplify voltage and/or current output by voice coil
135 corresponding to sound collected by sound transducer 132 (when
sound transducer 132 comprises a receiver and/or a microphone).
Either way, amplifier 137 is controlled by processor 120, as
depicted. While not depicted, sound transducer 132 further
comprises a membrane in communication with voice coil 135; when
sound transducer 132 comprises a loudspeaker, voice coil 135 moves
the membrane, under control of amplifier 137, resulting in sound
emitted from sound transducer 132, and when sound transducer 132
comprises a received and/or a microphone, voice coil 135 is moved
by the membrane, and amplifier 137 receives and amplifies output of
voice coil 135.
[0046] In implementations where sound transducer 132 comprises a
loudspeaker, device 101 can further comprise a microphone and, in
implementations where sound transducer 132 comprises a microphone,
device 101 can further comprise a loudspeaker. Indeed, each
loudspeaker and each microphone can be provided with a
corresponding amplifier and circuit equivalent to amplifier 137 and
circuit 138.
[0047] Processor 120 is generally configured to place amplifier 137
into a standby state where amplifier 137 is generally disabled so
that: a. amplifier 137 does not consume power and/or power
consumption by amplifier 137 is minimized; and b. sound transducer
132 does not operate to either emit or collect sound. In general,
processor 120 can place amplifier 137 into the standby state when
device 101 enters a standby state and/or a disabled state and/or a
hibernation state, where power consumption across a substantial
portion and/or all components of device 101 is minimized. For
example, the standby state can be entered after a period of
inactivity at device 101 and/or when device 101 enters a disabled
state and/or hibernation state; indeed, the standby state can
include, but is not limited to, a disabled state and/or a
hibernation state.
[0048] However, according to present implementations described in
further detail below, processor 120 generally controls circuit 138
to restrict excursion of voice coil 135 using an EMF when amplifier
137 enters the standby state. In other words, in present
implementations, in a standby state, EMF is used to restrict
excursion of voice coil 135 rather than voice coil 135 being
generally free to move, and hence in danger of being damaged when
device 101 is dropped and/or subjected to acceleration forces and
the like.
[0049] As depicted, circuit 138 can comprise a portion of amplifier
137 however, in other implementations, circuit 138 can be separate
from amplifier 137. Indeed, in general, circuit 138 comprises
electrical components configured to apply the EMF to voice coil 135
in the standby state. As will be described in further detail below,
when amplifier 137 is in the standby state, circuit 138 generally
comprises a resistance such that voice coil 135 is terminated in
the resistance, which is in turn in communication with power supply
136, voice coil 135 being otherwise controlled by amplifier
137.
[0050] In some implementations, device 101 and/or circuit 138,
further comprises a sensor configured to detect an output from
voice coil 135, the output being used to control the EMF. In other
implementations, device 101 and/or circuit 138, further comprises a
sensor, including, but not limited to an accelerometer, configured
to detect movement of device 101 and, when output from the sensor
and/or the accelerometer is above a threshold value, processor 120
control circuit 138 to apply the EMF to voice coil 135. In other
words, the threshold value can be associate with a given
acceleration and/or a given movement of device 101 above which
damage can be incurred at sound transducer 132 when a sudden stop
and/or a sudden change in velocity and/or a sudden change in
direction of device 101 occurs, voice coil 135 being restricted in
excursion.
[0051] In any event, it should be understood that a wide variety of
configurations for device 101 are contemplated. In particular, in
FIG. 2, a combination 140 of sound transducer 132, voice coil 135,
amplifier 137 and circuit 138 is indicated, and a various
implementations of such will be described in further detail
below.
[0052] Attention is now directed to FIG. 3 which depicts a
flowchart of a method 300 for sound transducer and/or voice coil
protection using damping, according to non-limiting
implementations. In order to assist in the explanation of method
300, it will be assumed that method 300 is performed using device
101, and specifically by processor 120 of device 101, for example
when processor 120 processes application 146. Indeed, method 300 is
one way in which device 101 can be configured. Furthermore, the
following discussion of method 300 will lead to a further
understanding of device 101, and its various components. However,
it is to be understood that device 101 and/or method 300 can be
varied, and need not work exactly as discussed herein in
conjunction with each other, and that such variations are within
the scope of present implementations.
[0053] Regardless, it is to be emphasized, that method 300 need not
be performed in the exact sequence as shown, unless otherwise
indicated; and likewise various blocks may be performed in parallel
rather than in sequence; hence the elements of method 300 are
referred to herein as "blocks" rather than "steps". It is also to
be understood, however, that method 300 can be implemented on
variations of system 100 as well.
[0054] At block 301, processor 120 places amplifier 137 into a
standby state. For example, processor 120 can place amplifier 137
in the standby state by turning off components of amplifier 137
other than those related to circuit 138, as described in further
detail below.
[0055] At block 303, when amplifier 137 is in the standby state,
processor 120 controls circuit 138 to apply an electromotive force
to voice coil 135 using power supply 136 so that voice coil 135 has
restricted excursion.
[0056] When device 101 comprises a sensor configured to detect an
output EMF from voice coil 135, block 303 can include processor 120
controlling circuit 138 to an EMF to voice coil 135 that is about
similar to the output EMF but in an opposite direction. In other
words, active damping of voice coil 135 occurs.
[0057] When device 101 and/or circuit 138 further comprises an
accelerometer in communication with processor 120, method 300 can
include processor 120 controlling circuit 138 to apply the EMF to
voice coil 135 when amplifier 137 is in the standby state, and when
output from the accelerometer is above a threshold value. In other
words, both conditions are satisfied so that controlling of circuit
138 to apply the EMF to voice coil 135 occurs.
[0058] Various implementations of a combination 140 of sound
transducer 132, voice coil 135, amplifier 137 and circuit 138 are
described below with reference to FIGS. 4 to 9.
[0059] For example, attention is next directed to FIG. 4, which
depicts components 440 of combination 140, according to
non-limiting implementations. In other words, combination 140 can
include components 440, however combination 140 can include other
components not depicted in FIG. 2.
[0060] Components 440 comprise: a load 435 which is representative
of voice coil 135, and is also labelled "Zload"; connections Vp, Vn
to power supply 136, with Vp comprising a connection to a positive
terminal of power supply 136, and Vn comprising a connection to a
negative terminal of power supply 136; and transistors TR1, TR2,
TR3, TR4 arranged in a Wheatstone bridge configuration with load
435, with connection Vn located between transistors TR1, TR2, and
connection Vp located between transistors TR3, TR4. In particular,
transistors TR1, TR2, TR3, TR4 can be components of amplifier 137,
with either of pair of transistors TR1, TR2 or pair of transistors
TR3, TR4 being components of circuit 138.
[0061] While not depicted in FIG. 4, it is assumed that processor
120 is in communication with each of transistors TR1, TR2, TR3, TR4
and that processor 120 can turn each of transistors TR1, TR2, TR3,
TR4 on or off. As depicted, processor 120 has controlled
transistors TR1, TR2 to an on-state, and transistors TR3, TR4 to an
off-state. As such, a resistance Ron of each of transistors TR1,
TR2, is "low" compared to a resistance Roff of each of transistors
TR3, TR4. In other words, resistance Roff of each of transistors
TR3, TR4 is generally very large and/or infinite and/or equal to an
open and/or off transistor resistance, and resistance Ron of each
of transistors TR1, TR2 is generally very small as compared to Roff
and/or equal to a closed and/or on transistor resistance.
Furthermore, Ron of each of transistors TR1, TR2 is about the
same.
[0062] As such, a circuit represented by load 435, transistor TR1,
connection Vn, transistor TR2, arranged in series, results in a net
EMF on load 435; specifically, an initial current Ispk flows in
this circuit to apply the EMF to load 435, represented by a voltage
Vspk across load 435. As load 435 represents voice coil 135, when
transistors TR1, TR2 are placed in the on-state, while transistors
TR3, TR4 are placed in the off-state, the net result is that the
EMF applied to load 435 restricts excursion of voice coil 135.
Hence, processor 120 when amplifier 137 is in the standby state,
processor 120 places transistors TR1, TR2 in the on-state, while
transistors TR3, TR4 are placed in the off-state, in order to apply
the EMF to voice coil 135. In other words, a termination resistance
of twice Ron assists with electromagnetic induction induced
current, Ispk, which produces the EMF that in turn restricts
movement of voice coil 135.
[0063] Hence, in these implementations circuit 138 comprises
transistor TR1, connection Vn, transistor TR2, arranged in series
with load 435, and circuit 138 comprises a resistance equivalent to
twice resistance Ron, such that voice coil 135 is terminated in a
resistance of twice Ron, which is in turn in communication with
power supply 136, when amplifier 137 is in the standby state, voice
coil 135 being otherwise controlled by the amplifier. In other
words, when amplifier 137 is not in the standby state, each of
transistors TR1, TR2, TR3, TR4 of amplifier 137 are used to control
voice coil 135 in accordance with program material so that sound is
emitted from sound transducer 132.
[0064] In particular, in implementations depicted in FIG. 4,
circuit 138 comprises two transistors TR1, TR2 in series with voice
coil 135 and a connection Vn to power supply 136 located between
the two transistors TR1, TR2, processor 120 configured to turn the
two transistors TR1, TR2 on when amplifier 137 is in the standby
state. In particular, amplifier 137 can comprise the two
transistors TR1, TR2, the two transistors TR1, TR2 used to drive
voice coil 135 to emit sound when amplifier 137 is not in the
standby state.
[0065] However, in other implementations, transistors TR3, TR4
could be used to apply the EMF to load 435 and/or voice coil 135 by
processor 120 placing transistors TR3, TR4 into an on-state and
placing transistors TR1, TR2 into an off-state.
[0066] In yet further implementations, circuit 138 could be in
addition to amplifier 137 so that the behaviour of amplifier 137
need not be modified in the standby state. In other words, a
circuit comprising two additional transistors in series with voice
coil 135 and a connection Vn to power supply 136 located between
the two additional transistors could be added to components 440 so
that transistors TR1, TR2, TR3, TR4 are always in the off-state in
the standby state, with the two additional transistors being in the
on-state when amplifier 137 is in the standby state, the two
additional transistors being otherwise in an off-state.
[0067] Attention is next directed to FIG. 5, which depicts a
circuit 540 which comprises a modelled equivalent to a circuit
represented by load 435, transistor TR1, connection Vn, transistor
TR2, arranged in series of FIG. 4. In particular, circuit 540
comprises a switch SW1, a resistance Rtm (i.e. a Terminator
resistance), a switch SW2, and a load 535 corresponding to voice
coil 135 arranged in series. While not depicted, it is assumed that
circuit 540 comprises a connection to power supply 136. Switches
SW1, SW2 and resistance Rtm are the equivalent of transistors TR1,
TR2 and resistances Ron of FIG. 4; hence, when each of switches
SW1, SW2 are closed (i.e. each of transistors TR1, TR2 are in an
on-state), a voltage VSpk occurs across load 535 and an EMF is
applied to voice coil 135.
[0068] Put another way, in present implementations, a sound
transducer (e.g. loudspeaker or receiver) amplifier output driver
is placed in a standby state so that no current flows loudspeaker
from a DC power supply, but rather the sound transducer is
terminated with a small resistance and/or inductance while in
standby state (which can also be referred to as a disabled state).
This termination by small resistance produced the path for and
electromagnetic induction induced current which in turn produces an
EMF that in turn restricts excursion of the sound transducer voice
coil and/or membrane. This "Protection" mode can be achieved by
activating both transistors TR1, TR1 of FIG. 4, but deactivating
both transistors TR3, TR4. Membrane/Voice-coil induced current can
be fed back to the sound transducer through transistors TR1, TR1
with very small resistance to cause a force (by back-emf) that
restricts the excursion and/or movement.
[0069] In reverse, activating both TR1 and TR2, and deactivating
both TR3 and TR4 will equally achieve same effects as above.
[0070] Attention is next directed to FIG. 6, which depicts a
circuit 640 which comprises another modelled equivalent to a
circuit represented by load 435, transistor TR1, connection Vn,
transistor TR2, arranged in series of FIG. 4. In particular, it is
assumed in FIG. 6 that each of transistors TR1, TR2 are in the
on-state, hence no switches are depicted. However, circuit 640
comprises an equivalent inductance Lspk and an equivalent
resistance Rdc of voice coil 135, as well as an equivalent
inductance Lres, an equivalent capacitance Cres and an equivalent
resistance Rres of the pair of resistors TR1, TR2 in the on-state,
as well as a resistance Rout that corresponds to an amplifier's
output impedance and/or a shunted resistance of the combination of
TR1 and TR2 (i.e. the total Ron in FIG. 4) (or alternatively the
combination of TR3 and TR3) when they are in a protection mode
(i.e. the combination of TR1 and TR2 are"ON" as in FIG. 4). A
resistance Rout that results in critical and/or smooth damping of
voice coil 135 can be calculated with equations that are also
depicted in FIG. 6 using a value of "Q" critical damping Q normally
selected in the range of 0.5 to 1.
[0071] Specifically, FIG. 6 also depicts equations that describe
modelling of a frequency behaviour of circuit 640 that include
definitions of a relative values of resistance Rdc with respect to
inductance Lspk, as well as relative values of resistance Rres with
respect to inductance Lres, each at a and a definition of a
resonance frequency of circuit 640 as follows:
Q=.omega.o*Cres*Rres*(Rout+Rdc)/(Rout+Rdc+Rres) Equation (1)
Q=0.5 Equation (2)
Rout = ( Rres + Rdc - 2 * .omega.o _ * Cres * Rres * Rout * Rdc ) (
2 * .omega.o _ * Cres * Rres - 1 ) Equation ( 3 ) ##EQU00001##
2.pi.foLspk<<Rdc Equation (4)
2.pi.foLres<<Rres Equation (5)
fo=1/(2*.pi.* {square root over (Lres*Cres)}) Equation (6)
[0072] In Equations (4), (5) and (6), .omega.o comprises angular
velocity, and fo comprises a loudspeaker's (acoustical) resonance
frequency, for example in the range of a few hundred Hertz.
Furthermore, Q can be set to about 0.5, and the equations solved
for Rout.
[0073] In any event, successful prototypes of device 101 using
components similar to components depicted in FIG. 4 were produced
and tested, with termination resistances of infinity and/or open,
5.OMEGA. and 0.47.OMEGA. used to test a prototype that includes a
sound transducer comprising a loudspeaker, and with termination
resistances of infinity and/or open, 31.6.OMEGA. and 0.47.OMEGA.
used to test a prototype that includes a sound transducer
comprising a receiver and/or microphone. In the test, a voice coil
of each prototype was terminated using one of the three respective
resistances so that excursion was restricted in a mimic of the
standby mode, and then each prototype was dropped onto a "hard"
floor from a height of about 10 cm, but with an accelerating force
applied to mimic a free fall drop from a larger height, on each of
the prototype's back, front and side. The resulting output voltage
of the voice coil was measured at the point of impact, with the
results for the loudspeaker implementation shown in Table 1, and
the results for the receiver implementation shown in Table 2. The
damping ratios for the 0.47.OMEGA. implementation, as compared to
each of the open and 5.OMEGA. implementations are also
provided.
TABLE-US-00001 TABLE 1 RESULTS OF LOUDSPEAKER PROTOTYPE TERMINATION
RESISTANCE DAMPING RATIO MODE OPEN 5.OMEGA. 0.47.OMEGA.
0.47.OMEGA./OPEN 0.47.OMEGA./5.OMEGA. Back 18.6 V 6.14 V 1.08 V
0.06 0.18 Front 18.7 V 6.31 V 1.00 V 0.05 0.16 Side 3.74 V 1.30 V
0.25 V 0.07 0.19
TABLE-US-00002 TABLE 2 RESULTS OF RECEIVER PROTOTYPE TERMINATION
RESISTANCE DAMPING RATIO MODE OPEN 31.6.OMEGA. 0.47.OMEGA.
0.47.OMEGA./OPEN 0.47.OMEGA./31.6.OMEGA. Back 17.9 V 10.62 V 0.37 V
0.02 0.03 Front 16.6 V 8.19 V 0.50 V 0.03 0.06 Side 7.68 V 2.66 V
0.22 V 0.03 0.08
[0074] In each case, the damping, when the termination resistance
(e.g. 0.47.OMEGA.) is small as compared to the open state is large
as compared to damping in the open state. In other words, the
measured voltage is representative of the excursion of the voice
coil at the point of impact, and the smaller the voltage in Tables
1, 2, the smaller the excursion of the voice coil. Hence, for the
0.47.OMEGA. termination resistance, the excursion of the voice coil
was restricted as compared to the other terminations. In
particular, the voice coil voltage is reduced to between about 2%
to about 7% when terminated in 0.47.OMEGA. as compared to the
unterminated and/or open state. In general 0.47.OMEGA. is similar
to the on-state resistances of two transistors, however other
termination resistances are within the scope of present
implementations. For example, Equations (1) to (6) can be solved
for Rout, using a given Q value (e.g. 0.5), and the resulting Rout
used to select the termination resistance.
[0075] Attention is next directed to FIG. 7 which depicts
components 740 of combination 140, according to alternative
non-limiting implementations. In other words, combination 140 can
include components 740, however combination 140 can include other
components not depicted in FIG. 7.
[0076] Components 740 comprise: a load 735 which is representative
of voice coil 135; a connections Vn to power supply 136, similar to
connection Vn of FIG. 2; transistors TR1, TR2, similar to
transistors TR1, TR2 of FIG. 2, and arranged in a similar manner; a
control signal generator 760, which can receive an ENABLE signal
from, for example, processor 120 (and/or processor 120 can comprise
control signal generator 760) and is otherwise in communication
with transistors TR1, TR2; and switches SW1, SW2, resistances R1,
R2 and a sensor 750 arranged in series with load 735. Switches SW1,
SW2 can be placed in an open state when amplifier 137 is not in the
standby mode and placed in a closed state, as depicted, when
amplifiers 137 is in the standby mode, switches SW1, SW2 being
controlled by processor 120 (e.g. using the ENABLE signal shown in
FIG. 7). While two switches SW1 SW2 and two resistors R1, R2 are
depicted, in other implementations components 740 can include as
few as one switch and one resistor. In general, resistors R1, R2
are present to control a magnitude of an output signal from load
735 to sensor 750. Transistors TR1, TR2 can be components of
amplifier 137, or transistors TR1, TR2 can comprise components
separate from amplifier 137. In general, circuit 138 comprises
components 740 other than load 735.
[0077] An output of sensor 750 is generally in communication with
control signal generator 760, and control signal generator 760
(and/or processor 120) is generally configured to control
transistors TR1, TR2 using the output from sensor 750. For example,
when the output from sensor 750 is above a threshold value
associated with excessive movement of voice coil 135, then control
signal generator 760 can control transistors TR1, TR2 to be in an
on-state, as in FIG. 2. Alternatively, control signal generator 760
(and/or processor 120) can control transistors TR1, TR2 to be in an
on-state whenever there is an output from sensor 750; for example,
as depicted sensor 750 comprises a diode, and the diode will only
generate an output when a signal from load 735 is above the
threshold for the diode.
[0078] Hence, in implementations depicted in FIG. 7, device 101
further comprises sensor 750 and one or more switches SW1, SW2
configured to connect voice coil 135 (i.e. load 735) with sensor
750 when the one or more switches SW1, SW2 are closed, sensor 750
configured to detect an output from voice coil 135 (i.e. load 735),
processor 120 and/or control signal generator 760 further
configured to: close one or more switches SW1, SW2 when amplifier
137 is in the standby state, and otherwise open one or more
switches SW1, SW2; and when amplifier 137 is in the standby state,
and when the output of voice coil 135, as detected by sensor 750,
is above a threshold value, control circuit 138 (e.g. at least
transistors TR1, TR2) to apply an EMF to voice coil 135 (e.g. load
735) using power supply 136 (e.g. connection Vn).
[0079] Put another way, transducer induced output can be large
enough to produce a power needed to drive sensor 750 and associated
circuitry. In the standby state, two switches SW1 and SW2 are in
On-state. An event of sudden acceleration, load 735 (i.e. a
transducer and/or a voice coil) produces large enough output that
is fed to a rectification circuit. Transistors TR1, TR2 can act as
part of loudspeaker amplifier's output driver when the amplifier is
in active state.
[0080] In particular, components 740 are arranged in a passive
damping configuration. However, active damping of voice coil 135 is
also within the scope of present implementations.
[0081] For example, attention is next directed to FIG. 8, which
depicts components 840 of combination 140, according to alternative
non-limiting implementations. In other words, combination 140 can
include components 840, however combination 140 can include other
components not depicted in FIG. 8.
[0082] Components 840 comprise: a load 835 which is representative
of voice coil 135; an amplifier 837, similar to amplifier 137 and
while not depicted, amplifier 837 can comprises a plurality of
transistors and power supply connections similar to those depicted
in FIG. 4; and a sensor 850 connected across load 835. While all
connections from amplifier 837 to load 835 are not depicted, it is
appreciated that connections from amplifier 837 to load 835 are
similar to those depicted in FIG. 4, presuming amplifier 837
comprises transistors similar to those depicted in FIG. 4. Further,
sensor 850 can be similar to sensor 750, however sensor 850 can
further comprise switches similar to switches SW1, SW2 in FIG. 7
(as well as resistors, also similar to FIG. 7), so that sensor 850
can be connected and disconnected from load 835 depending on a
state of amplifier 837. For example, sensor 850 can be in
communication with processor 120 so that an "ENABLE_CONTROL" signal
can be received from processor 120, which causes associated
switches to close to connect sensor 850 to load 835 or
alternatively causes associated switches to open to disconnect
sensor 850 from load 835. In general, sensor 850 is across load 850
when amplifier 837 is placed into a standby state and disconnected
otherwise.
[0083] Furthermore, amplifier 837 can be enabled or disabled via an
input that receives an "AMP_ENABLE" signal from processor 120,
though, in present implementations, as amplifier 837 is used to
apply the EMF to load 835 (i.e. voice coil 135) in the standby
state, amplifier 837 is enabled in the standby state.
[0084] Components 840 further comprise a switch 870 that can be
switched between a connection Vn to power supply 136 and an audio
input ("INPUT ON", e.g. from processor 120 and/or another source of
program material), switch 870 being in communication with, and
being controlled by, processor 120 such that upon receipt of an
"AUDIO_ENABLE" signal from processor 120, switch 870 is switched
between connection Vn and the audio input depending on whether
amplifier 837 is being placed in a standby state (with no audio
input, and connected to connection Vn) or not in a standby state
(i.e. connected to audio input).
[0085] In other words, processor 120 can place amplifier 837 into
the standby state by controlling switch 870 to switch from the
audio input to connection Vn, and, in conjunction connect sensor
850 to load 835.
[0086] Sensor 850 is generally configured to detect an output EMF
from load 835 (i.e. voice coil 135) for example as excursion of
voice coil 135 changes as device 101 moves, and detects the output
EMF in the standby state. As such, sensor 850 can comprise one or
more of a diode, a voltmeter, an ohmmeter, and the like.
[0087] An output of sensor 850 is in communication with an input of
amplifier 837 so that the amplifier 837 can control the EMF on load
835 (i.e. voice coil 135) according to the output of sensor 850
("SENSE-FB"). In other words, sensor 850 and amplifier 837 form a
motional feedback loop with load 835 so that amplifier 837 can
actively damp voice coil 135.
[0088] In other words, in implementations depicted in FIG. 8,
device 101 further comprises sensor 850 configured to detect an
output EMF from voice coil 135, and circuit 138 is further
configured to apply EMF to voice coil 135, the EMF being about
similar to the output EMF but in an opposite direction. Hence, as
depicted in FIG. 8, circuit 138 comprises components of amplifier
837 that can apply an EMF to load 835 (i.e. voice coil 135), as
well sensor 850 and corresponding connections there between. Such
implementations can be referred to as "active damping" of voice
coil 135.
[0089] Put another way, components 840 comprise a combination of a
driver amplifier 937 with transducer feed-back using a transducer
membrane/voice-coil movement sensor. Driver amplifier 837
terminates a loudspeaker voice coil with low impedance and/or low
resistance (as per FIGS. 5 and 6) in an event of sudden
acceleration during standby/disable state. Also amplifier 837 can
act as a motional feed-back system, with sensor 850, that senses
membrane/voice-coil excursion, and responsively controls applied
EMF to minimize the excursion.
[0090] Furthermore, while implementations depicted in FIG. 8 are
described with reference to an audio input, and hence it is assumed
that load 835 and/or voice coil 135 is a component of a
loudspeaker, similar implementations can be applied to
receivers.
[0091] Attention is next directed to FIG. 9, which depicts
components 940 of combination 140, according to alternative
non-limiting implementations. In other words, combination 140 can
include components 940, however combination 140 can include other
components not depicted in FIG. 9.
[0092] Components 940 are substantially similar to components 840,
with like elements having like numbers, but preceded by a "9"
rather than an "8". For example, components 940 comprise: a load
935 which is representative of voice coil 135; an amplifier 937;
and a sensor 950 connected across load 935. While all connections
from amplifier 937 to load 935 are not depicted, it is appreciated
that connections from amplifier 937 to load 935 are similar to
those depicted in FIG. 4, presuming amplifier 937 comprises
transistors similar to those depicted in FIG. 4. Further, sensor
950 can be similar to sensor 850 with an output of sensor 950
connected to an input to amplifier 937, as in FIG. 8. Components
940 further comprise a switch 970, similar to switch 870, and
connections to a connection Vn to power supply 136, and an audio
input from processor 120, with switch being under control of
processor 120.
[0093] However, in contrast to components 840, components 940
further comprise an accelerometer 960 (which can include a
controller), with an input of accelerometer 960 connected to an
output of sensor 950, and an output of accelerometer 960 connected
to an input of amplifier 937. Accelerometer 960 is generally
configured to measure movement and/or an acceleration of device
101, and provides a control signal ("CONTROL") to amplifier 937
indicative of such movement and/or acceleration. When the control
signal is above a threshold value and when amplifier 937 is in a
standby state, as described above, the EMF is applied to load 935
(i.e. voice coil 135) to restrict movement thereof.
[0094] In other words, in these implementations, the EMF is not
applied to voice coil 135 unless device 101 is moving and/or
accelerating above a threshold value.
[0095] Hence, in these implementations, device 101 device of claim
1, further comprising accelerometer 960, and processor 120 is
further configured to: when amplifier 937 is in the standby state,
and when output from accelerometer 960 is above a threshold value,
control circuit 138 to apply EMF to voice coil 135 to restrict
excursion thereof.
[0096] Put another way, an accelerometer configured to detect a
sudden movement of device 101, during a fall for instance, is used
to activate voice-coil termination circuitry. This preventative
protection can further protect a sound transducer's membrane/voice
coil assembly in the event of sudden acceleration.
[0097] Furthermore, while implementations depicted in FIG. 9 are
described with reference to an audio input, and hence it is assumed
that load 935 and/or voice coil 135 is a component of a
loudspeaker, similar implementations can be applied to
receivers.
[0098] Those skilled in the art will appreciate that in some
implementations, the functionality of device 101 and/or the speaker
circuit of FIG. 64 can be implemented using pre-programmed hardware
or firmware elements (e.g., application specific integrated
circuits (ASICs), electrically erasable programmable read-only
memories (EEPROMs), etc.), or other related components. In other
implementations, the functionality of device 101 and/or the speaker
circuit of FIG. 64 can be achieved using a computing apparatus that
has access to a code memory (not depicted) which stores
computer-readable program code for operation of the computing
apparatus. The computer-readable program code could be stored on a
computer readable storage medium which is fixed, tangible and
readable directly by these components, (e.g., removable diskette,
CD-ROM, ROM, fixed disk, USB drive). Furthermore, the
computer-readable program can be stored as a computer program
product comprising a computer usable medium. Further, a persistent
storage device can comprise the computer readable program code. The
computer-readable program code and/or computer usable medium can
comprise a non-transitory computer-readable program code and/or
non-transitory computer usable medium. Alternatively, the
computer-readable program code could be stored remotely but
transmittable to these components via a modem or other interface
device connected to a network (including, without limitation, the
Internet) over a transmission medium. The transmission medium can
be either a non-mobile medium (e.g., optical and/or digital and/or
analog communications lines) or a mobile medium (e.g., microwave,
infrared, free-space optical or other transmission schemes) or a
combination thereof.
[0099] A portion of the disclosure of this patent document contains
material which is subject to copyright protection. The copyright
owner has no objection to the facsimile reproduction by any one of
the patent document or patent disclosure, as it appears in the
Patent and Trademark Office patent file or records, but otherwise
reserves all copyrights whatsoever
[0100] Persons skilled in the art will appreciate that there are
yet more alternative implementations and modifications possible,
and that the above examples are only illustrations of one or more
implementations. The scope, therefore, is only to be limited by the
claims appended hereto.
* * * * *