US 9,941,830 B2
`(10) Patent No.:
`a2) United States Patent
`Elengaet al.
`(45) Date of Patent:
`Apr.10, 2018
`
`
`US009941830B2
`
`(54) LINEAR VIBRATION MODULES AND
`LINEAR-RESONANT VIBRATION MODULES
`
`(72)
`
`(71) Applicant: Resonant Systems, Inc., Seattle, WA
`(US)
`Inventors: Robin Elenga, Seattle, WA (US); Brian
`Mare Pepin, Oakland, CA (US); Glen
`Tompkins, Woodinville, WA (US)
`(73) Assignee: Kesonant Systems, Inc., Seattle, WA
`(US)
`;
`——
`;
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`:
`
`.
`
`;
`(*) Notice:
`
`(21) Appl. No.: 15/181,249
`
`(22)
`
`Filed:
`
`Jun. 13, 2016
`
`(65)
`
`Prior Publication Data
`US 2016/0301346 Al
`Oct. 13, 2016
`
`(58) Field of Classification Search
`CPC ...... H02P 25/032; HO2K 7/1876; BO6B 1/166
`See application file for complete search history.
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS.
`
`1,120,414 A
`3,728,654 A
`4,549,535 A
`4,692,990 A
`5,017,819 A
`5,187,398 A
`5,231,336 A
`
`12/1914 Schoolfield et al.
`4/1973 Tada
`10/1985 Wing
`9/1987 Framisen
`5/1991 Patt et al.
`2/1993 Stuart etal.
`7/1993 van Namen
`(Continued)
`
`FOREIGN PATENT DOCUMENTS
`
`EP
`
`1 376 833 Al
`
`1/2004
`
`Primary Examiner — Karen Masih
`(74) Attorney, Agent, or Firm — Olympic Patent Works
`PLLC
`
`Related U.S. Application Data
`
`(57)
`
`ABSTRACT
`
`(63) Continuation of application No. 14/469,210, filed on
`Aug. 26, 2014, now Pat. No. 9,369,081, which is a
`continuation of application No. 13/345,607, filed on
`Jan. 4, 2012, now Pat. No. 8,860,337, which is a
`continuation-in-part of application No. 12/782,697,
`filed on May 18, 2010, now Pat. No. 8,093,767.
`(60) Provisional application No. 61/179,109, filed on May
`18. 2009
`;
`‘
`Int. CL
`HO2K 33/00
`HO2P 25/032
`HO2K 33/16
`(52) U.S. CL
`CPC we. HO02P 25/032 (2016.02), HO2K 33/16
`(2013.01)
`
`(2006.01)
`(2016.01)
`(2006.01)
`
`(51)
`
`The current application is directed to various types oflinear
`vibrational modules,
`including linear-resonant vibration
`modules that can be incorporated in a wide variety of
`appliances, devices, and systems to provide vibrational
`forces. The vibrational forces are produced by linear oscil-
`lation of a weight or member, in turn produced by rapidly
`alternating the polarity of one or more driving electromag-
`nets. Feedback control is used to maintain the vibrational
`frequency of linear-resonant vibration module at or near the
`resonant frequency for the linear-resonant vibration module.
`Both linear vibration modules andlinear-resonant vibration
`modules can be designed to produce vibrational amplitude/
`frequency combinations throughout a large region of ampli-
`tude/frequency space.
`
`20 Claims, 20 Drawing Sheets
`
`user controls
`
`
`
`612
`
`powersupply
`}
`(
`'
`
`
`
`
`
`
`Loans 7 830
`ie 604
`
`
`
`/ 600 [ 614
`
`
`
`
`111iIiiIiiiL'F'ttt'l
`
`
`
`
`sensor
`
`
`
`
`
`I\6
`
`
`
`1
`
`APPLE 1001
`
`APPLE 1001
`
`1
`
`

`

`US 9,941,830 B2
` Page 2
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`2011/0144426 A1*
`
`7/1993 van Namen
`5,231,337 A
`6/1995 Bluenet al.
`5,424,592 A
`4/1999 van Narnen
`5,896,076 A
`9/1999 Amayaetal.
`5,955,799 A
`10/1999 Clamme
`5,973,422 A
`11/2001 Zabar
`6,323,568 Bl
`12/2001 Zhang
`6,326,706 Bl
`11/2008 Sahyoun
`7,449,803 B2
`1/2009 Shimizu et al.
`7,474,018 B2
`8/2010 Sahyoun
`7,768,160 Bl
`8/2010 Aschoff et al.
`7,768,168 B2
`8/2010 Madsenetal.
`7,771,348 B2
`7,859,144 Bl=12/2010 Sahyoun
`2004/0055598 Al
`3/2004 Crowder etal.
`2005/0231045 Al
`10/2005 Obaetal.
`2005/0275508 Al
`12/2005 Orret al.
`2006/0138875 Al
`6/2006 Kim etal.
`2006/0208600 Al
`9/2006 Sahyoun
`2007/0261185 A1* 11/2007 Guney ou... A46B 15/0002
`15/22.1
`6/2011 Blenk wo. A61H 23/02
`600/38
`2011/0248817 A1* 10/2011 Houston ww . A63F 13/06
`340/4.2
`
`2012/0212895 Al
`
`8/2012 Cohen et al.
`
`* cited by examiner
`
`2
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 1 of 20
`
`US 9,941,830 B2
`
`z &
`
`xy
`v~ <<
`
`8i
`
`«Oo
`S
`
`3S
`
`mj
`NT
`os
`iF
`
`3
`
`

`

`U.S. Patent
`
`Apr.10, 2018
`
`Sheet 2 of 20
`
`US 9,941,830 B2
`
`
`
`222
`
`220
`
`FIG. 2A
`
`--Prior Art-
`
`FIG. 2B
`
`--Prior Art--
`
`4
`
`

`

`U.S. Patent
`
`Apr.10, 2018
`
`Sheet 3 of 20
`
`US 9,941,830 B2
`
`80Hz
`
`FIG.3 --PriorAri--
`
`frequency
`
`vibrational
`
`force
`
`5
`
`

`

`U.S. Patent
`
`Apr.10, 2018
`
`Sheet 4 of 20
`
`US 9,941,830 B2
`
`
`414
`
`6
`
`

`

`U.S. Patent
`
`Apr.10, 2018
`
`Sheet 5 of 20
`
`US 9,941,830 B2
`
`
`
`FIG. 4E
`
`
`
`7
`
`

`

`U.S. Patent
`
`Apr.10, 2018
`
`Sheet 6 of 20
`
`US 9,941,830 B2
`
`FIG.5B
`FIG.5A
`
`co
`res
`
`&o
`
`S
`re)
`
`8
`
`

`

`U.S. Patent
`
`Apr.10, 2018
`
`Sheet 7 of 20
`
`US 9,941,830 B2
`
`606
`
`/
`
`614
`
`/-
`
`user controls
`
`I 609
`
`608 | 610
`
`6
`
`16
`
`CPU
`
`r
`|
`; memory !
`I
`1
`; as
`
`502
`
`ie 604
`
`630
`
`powersupply
`
`612
`
`618
`
`622
`
`620
`
`H switch
`
`=[i
`
`sensor
`
`632
`
`9
`
`

`

`U.S. Patent
`
`Apr.10, 2018
`
`Sheet 8 of 20
`
`US 9,941,830 B2
`
`control program
`
`iO = default 4 702
`
`mode = default
`strength = default
`
`iid = default
`freq = default
`d= default
`inc = true
`
`wait for event
`
`
`
`708
`
`d=-d;
`output d;
`reset frequency
`timer
`
`frequency timer
`expired
`?
`
`
`
`monitor
`
`monitor
`
`control
`
`timer expiration
`
`
`power down device
`
`power down
`>
`
`
`
`handie other
`events
`
`
`FIG. 7A
`
`10
`
`10
`
`

`

`U.S. Patent
`
`Apr.10, 2018
`
`Sheet 9 of 20
`
`US 9,941,830 B2
`
`monitor
`
`
`
`connect sensor input
`to integer and store
`in diz
`
`== default
`
`handle non-
`default mode
`
`740
`
`
`
`
`
`
`
`
`
`freq = freq+ 1
`reset frequency
`
`freq = freq - 1;
`inc =f;
`Teset frequency
`
`freq = freq - 1;
`reset frequency
`timer
`
`freq = freq +1
`inc =T;
`reset frequency
`timer
`
`MO = iid;
`reset monitor timer
`
`FIG. 7B
`
`11
`
`11
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 10 of 20
`
`US 9,941,830 B2
`
`mode =
`
`currently selected Lo 760
`
`made;
`strength = currently
`
`selected strength
`
`
`compute output p to
`power supply;
`output p to power
`supply
`
`compute and reset
`monitor timer
`interval
`
`762Lo
`
`764f
`
`FIG. 7C
`
`12
`
`12
`
`

`

` FIG.8
`
`13
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 12 of 20
`
`US 9,941,830 B2
`
` 0
`
`350Hz
`
`frequency
`
`250H2
`
`‘ ly
`v
`V
`
`902
`
`FIG. 9
`
`14
`
`14
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 13 of 20
`
`US 9,941,830 B2
`
`electromagnet
`
`mass centering
`element
`
`moving mass
`
`1002
`
`FIG. 10
`
`permanent
`magnetstixed on
`exterior
`
`driving coil
`attached to
`moving weight
`
`
`
`
` (+)pole magnets repel
`-} pole
`magnets
`
`-) pole
`ale
`repel
`
`
`
`+)
`
`driving magnet
`
`
`FIG. 11
`
`1102
`
`tube
`
`4202
`rotational
`
`
`rotational
`
`
`centering
`
`moveable
`: weight
`©
`:
`magnet |
`
`
`rotational
`
`
`coil
`
`1206
`
`
`
`rotation actian
`
`15
`
`15
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 14 of 20
`
`US 9,941,830 B2
`
`
`
`1404
`
`driving magnet
`
`We
`=
`ih
`
`
`
`
`
`
`1406
`1412
`
`riving coi
`
`1414
`
`4402
`
`1414
`
`4420
`
`E-coil
`electromagnet
`
`
`
`
`body/handie
`
`control
`
`unit
`
`
`
`
`
`exterior of device
`
`16
`
`16
`
`

`

`U.S. Patent
`
`Apr.10, 2018
`
`Sheet 15 of 20
`
`US 9,941,830 B2
`
`
`
`spring
`
`
`magnet
`E-coil
`1602
`electromagnet
`
`1606
`clamp/hinge
`
`massage foot
`
`motion of
`massage arm
`
`contral
`unit
`
`
`
`
`body/handle
`
`
`
`
`
`motion of magnet
`
`exterior of device
`
`arm extends
`outside of device
`
`FIG. 16
`
`
`
`moveable spring
`clamp
`
`spring
`
`
`
`
`spring clamps
`
`1702
`
`adjustment
`screw
`
`clamp
`movement
`
`FIG. 17
`
`
`
`FIG. 18
`
`17
`
`17
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 16 of 20
`
`US 9,941,830 B2
`
`6)Old
`
`Aouanbal4pos!
`
`
`
`juBUOSeyAouanbay
`
`apnyydwe
`
`18
`
`18
`
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 17 of 20
`
`US 9,941,830 B2
`
`ZL0¢
`
`01028002
`
`9002
`
`eapnyduwe
`
`
`
`C002
`
`Aouanbay
`
`0¢Sls
`
`7002
`
`19
`
`19
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 18 of 20
`
`US 9,941,830 B2
`
`Aouenbe-j
`
`
`
`o0L2—~_prowseud
`
`Aduenbas4
`
`leOld
`
`epnyiduiy
`
`20
`
`20
`
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 19 of 20
`
`US 9,941,830 B2
`
`2204
`
`
`
`VibrationAmptitude b
`
`.
`
`O6
`time (s)
`
`FIG. 22B
`
`bo
`
`2206
`
`FIG, 22A
`
`* time s)
`
`i
`Wi
`
`vibrationeee
`
`
`
`
`
`
`VibrationAmplitude
`
`eecewereeeeeeeede PPEIP
`
`64
`
`time (s)
`
`58
`
`FIG. 23
`
`21
`
`21
`
`

`

`U.S. Patent
`
`Apr. 10, 2018
`
`Sheet 20 of 20
`
`US 9,941,830 B2
`
`Stator Cait
`
`2416
`1
`
`
`
`
`!i
`
`1
`
`Flux Path
`
`2404
`
`Stator Cait
`
`
`
`Centering
`Magnet
`
`Piston
`+
`Direction
`of
`Movement
`
`
`
`FIG. 24A
`
`
`Piston
`
`. t
`Direction
`
`Movement
`2415
`
`]
`
`Cantering
`i Magnet
`
`2411
`
`2410
`
`Massage Foot
`
`FIG. 24B
`
`2508
`Flux Path
`
`Stator Coil
`
`Centering
`Magnet
`
`NS 2504
`
`
`
`
`
`|
`
`
`
`Piston
`
`Direction
`of
`Movement
`
`Massage Foot
`
`FIG. 25
`
`22
`
`22
`
`

`

`US 9,941,830 B2
`
`1
`LINEAR VIBRATION MODULES AND
`LINEAR-RESONANT VIBRATION MODULES
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`This application is a continuation of application Ser. No.
`14/469,210, filed Aug. 26, 2014, which is a continuation of
`USS. Pat. No. 8,860,337, issued Oct. 14, 2014, which is a
`continuation-in-part of U.S. Pat. No. 8,093,767, issued Jan.
`10, 2012, which claims the benefit of Provisional Patent
`Application No. 61/179,109, filed May 18, 2009.
`
`TECHNICAL FIELD
`
`The current application is related to vibration-generating
`devices and, in particular, to vibration modules that can be
`incorporated into a wide variety of different types of elec-
`tromechanical devices and systems to produce vibrations of
`selected amplitudes and frequencies over a wide range of
`amplitude/frequency space.
`
`BACKGROUND
`
`Vibration-inducing motors and mechanisms have been
`used for many years in a wide variety of different consumer
`appliances, toys, and other devices and systems. Examples
`include vibration signals generated by pagers, vibration-
`driven appliances, such as hair-trimming appliances, electric
`toothbrushes, electric toy football games, and many other
`appliances, devices, and systems. The most commonelec-
`tromechanical system used for generating vibrations is an
`intentionally unbalanced electric motor.
`FIGS. 1A-B illustrate an unbalanced electric motor typi-
`cally used for generating vibrations in a wide variety of
`different devices. As shown in FIG. 1A, a small, relatively
`low-powerelectric motor 102 rotates a cylindrical shaft 104
`onto which a weight 106 is asymmetrically or mounted. FIG.
`1B showsthe weight asymmetrically mounted to the shaft,
`looking downat the weight and shaft in the direction of the
`axis of the shaft. As shown in FIG. 1B, the weight 106 is
`mounted off-center on the electric-motor shaft 104. FIGS.
`
`2A-B illustrate the vibrational motion produced by the
`unbalancedelectric motor shown in FIGS. 1A-B. As shown
`in FIGS. 2A-B, the asymmetrically-mounted weight creates
`an elliptical oscillation of the end of the shaft, normalto the
`shaft axis, when the shaft is rotated at relatively high speed
`by the electric motor. FIG. 2A shows displacement of the
`weight and shaft from the stationary shaft axis as the shaft
`is rotated, looking down on the weight and shaft along the
`shaft axis, as in FIG. 1B. In FIG. 2A, a small mark 202 is
`provided at the periphery of the disk-shaped end the of
`electric-motor shaft to illustrate rotation of the shaft. When
`the shaft rotates at high speed, a point 204 on the edge of the
`weighttraces an ellipsoid 206 andthe center of the shaft 208
`traces a narrower and smaller ellipsoid 210. Were the shaft
`balanced, the center of the shaft would remain at a position
`212 in the center of the diagram during rotation, but the
`presence of the asymmetrically-mounted weight attached to
`the shaft, as well as other geometric and weight-distribution
`characteristics of the electric motor, shaft, and unbalanced
`weight together create forces that move the end of the shaft
`along the elliptical path 210 when the shaft is rotated at
`relatively high speed. The movement can be characterized,
`as shown in FIG. 2B, by a major axis 220 and minor axis 222
`ofvibration, with the direction of the major axis of vibration
`equal to the direction of the major axis of the ellipsoids,
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`2
`shown in FIG. 2A, and the length of the major axis corre-
`sponding to the amplitude of vibration in this direction. In
`many applications, in which a linear oscillation is desired,
`designers seek to force the major-axis-amplitude/minor-
`axis-amplitude ratio to be as large as possible, but, because
`the vibration is producedbya rotationalforce, it is generally
`not possible to achieve linear oscillation. In many cases, the
`path traced by the shaft center may be close to circular. The
`frequency of vibration of the unbalanced electric motor is
`equal to the rotational frequency ofthe electric-motor shaft,
`and is therefore constrained by the rate at which the motor
`can rotate the shaft. At low rotational speeds,little vibration
`is produced.
`While effective in producing vibrations, there are many
`problems associated with the unbalanced-electric-motor
`vibration-generating units, such as that shown in FIG. 1A,
`commonly used in the various devices, systems, and appli-
`cations discussed above. First, unbalancing the shaft of an
`electric motor not only produces useful vibrations that can
`be harnessed for various applications, but also produces
`destructive, unbalanced forces within the motor that con-
`tribute to rapid deterioration of motor parts. Enormous care
`and effort is undertaken to precisely balance rotating parts of
`motors, vehicles, and other types of machinery, and the
`consequencesof unbalancedrotating parts are well knownto
`anyone familiar with automobiles, machine tools, and other
`such devices and systems. The useful
`lifetimes of many
`devices and appliances, particularly hand-held devices and
`appliances, that employ unbalanced electric motors for gen-
`erating vibrations may range from a few tens of hours to a
`few thousands of hours of use, after which the vibrational
`amplitude produced by the devices declines precipitously as
`the electric motor and other parts deteriorate.
`A secondproblem with unbalancedelectric motors is that
`they are relatively inefficient at producing vibrational
`motion. A far greater amount of power is consumed by an
`unbalanced electrical motor to produce a given vibrational
`force than the theoretical minimum powerrequired to pro-
`duce the given vibrational force. As a result, many hand-held
`devices that employ unbalanced electric motors for gener-
`ating vibrations quickly consumebatteries during use.
`A third problem with unbalanced electric motors, dis-
`cussed above, is that they generally produceelliptical vibra-
`tional modes. Although such modes may be useful in par-
`ticular applications, many applications canbetter use a linear
`oscillation, with greater directional concentration of vibra-
`tional forces. Linear oscillation cannot generally be pro-
`duced by unbalancedelectric motors.
`A fourth, and perhaps most fundamental, problem asso-
`ciated with using unbalanced electric motors to generate
`vibrations is that only a very limited portion of the total
`vibrational-force/frequency space is accessible to unbal-
`anced electric motors. FIG. 3 shows a graph of vibrational
`force with respect to frequency for various types of unbal-
`anced electric motors. The graph is shown as a continuous
`hypothetical curve, although, of course, actual data would be
`discrete. As shown in FIG. 3, for relatively low-power
`electric motors used in hand-held appliances, only a fairly
`narrow range of frequencies centered about 80 Hz (302 in
`FIG. 3) generate a significant vibrational force. Moreover,
`the vibrational force is relatively modest. The bulk of energy
`consumed by an unbalanced electric motor is used to spin
`the shaft and unbalanced weight and to overcomefrictional
`and inertial forces within the motor. Only a relatively small
`portion of the consumed energy is translated into desired
`vibrational forces.
`
`23
`
`23
`
`

`

`US 9,941,830 B2
`
`3
`Because of the above-discussed disadvantages with the
`commonly employed unbalanced-electric-motor vibration-
`generation units, designers, manufacturers, and, ultimately,
`users of a wide variety of different vibration-based devices,
`appliances, and systems continue to seek moreefficient and
`capable vibration-generating units for incorporation into
`many consumer appliances, devices, and systems.
`
`SUMMARY
`
`The current application is directed to various types of
`linear vibrational modules, including linear-resonant vibra-
`tion modules, that can be incorporated in a wide variety of
`appliances, devices, and systems to provide vibrational
`forces. The vibrational forces are produced by linear oscil-
`lation of a weight or member, in turn produced by rapidly
`alternating the polarity of one or more driving electromag-
`nets. Feedback control is used to maintain the vibrational
`
`frequency oflinear-resonant vibration module at or near the
`resonant frequency for the linear-resonant vibration module.
`Both linear vibration modules and linear-resonant vibration
`
`4
`FIG. 19 illustrates plots of amplitude versus frequency for
`a high-Q and a low-Q vibration device.
`FIG.20 illustrates portions of amplitude/frequency space
`accessible to various types of vibration modules.
`FIG. 21 illustrates the dependence between frequency and
`amplitude in a low-Q linear vibration module as well as a
`modified dependence that can be obtained by control cir-
`cuitry.
`FIGS. 22A-23 illustrate interesting vibrational modes
`produced by driving a linear-resonant vibration module
`simultaneously at two different frequencies.
`FIGS. 24A-25 illustrate incorporation of paramagnetic
`flux paths into a linear vibration module.
`
`10
`
`DETAILED DESCRIPTION
`
`The current application is directed to various linear vibra-
`tion modules (““LRMs”), including various types of linear-
`resonant vibration modules (‘LRVMs”), that can be used
`within a wide variety of different
`types of appliances,
`devices, and systems, to generate vibrational forces. The
`LVMs and LRVMsthat represent embodiments of the cur-
`rent application are linear in the sense that the vibrational
`forces are produced bya linear oscillation of a weight or
`component within the LVM or LRVM,rather than as a
`by-product of an unbalanced rotation, as in the case of
`currently employed unbalanced electric motors. The linear
`nature of the LRVM vibration-inducing motion allows the
`problemsassociated with unbalanced-electric-motor vibra-
`tors, discussed above, to be effectively addressed. An oscil-
`lating linear motion does not produce destructive forces that
`quickly degrade and wear out an unbalanced electric motor.
`A linearly oscillating mechanism is characterized by param-
`eters that can be straightforwardly varied in order to produce
`vibrations of a desired amplitude and frequency over a very
`broad region of amplitude/frequency space. In many imple-
`mentations of LRVMs and LVMs, the vibration amplitude
`and vibration frequency can be independently controlled by
`a user through user-input features, including buttons, sliders,
`and other types of user-input features. Combining a linearly
`oscillating vibration-inducing mechanism with feedback
`control, so that the frequency of vibration falls close to the
`resonant frequency of the LRVM,results in optimal power
`consumption with respect to the amplitude and frequency of
`vibration produced by the LRVM.Clearly, linear oscillation
`within a LRVMtranslates into highly direction vibrational
`forces produced by an appliance or device that incorporates
`the LRVM.
`FIGS. 4A-Gillustrate one particular LRVM,and opera-
`tion of the particular LRVM,that represents one implemen-
`tation of the linear-resonant vibration module to which
`current application is directed. FIGS. 4A-G all use the same
`illustration conventions, next discussed with reference to
`application is directed.
`FIG. 4A. The LRVM includes a cylindrical housing 402
`FIG.8 represents the range of frequencies and vibrational
`within which a solid, cylindrical mass 404, or weight, can
`forces that can be achieved by different implementations of
`movelinearly along the inner, hollow, cylindrically shaped
`LRVM and LRVMcontrol programs that represent embodi-
`chamber 406 within the cylindrical housing or tube 402. The
`ments of the current application.
`weight is a magnet, in the described an implementation of
`FIG. 9 showsa plot of the amplitude/frequency space and
`the linear-resonant vibration module to which current appli-
`regions in that space that can be operationally achieved by
`cation is directed, with polarity indicated by the “+” sign 410
`unbalanced electrical motors and by LRVMsthat represent
`embodiments of the current application.
`on the right-hand end and the “—” sign 412 on the left-hand
`
`FIGS. 10-17 showavariety of different alternative imple- end of the weight 404. The cylindrical chamber 406 is
`mentations of LRVMsthat represent different embodiments
`capped by two magnetic disks 414 and 416 with polarities
`of the current application.
`indicated by the “+” sign 418 and the ‘“—” sign 419. The
`FIG. 18 illustrates an enhancementof an implementation
`disk-like magnets 414 and 418 are magnetically oriented
`of the linear-resonant vibration module to which current
`opposite from the magnetic orientation of the weight 404, so
`that when the weight moves to either the extreme left or
`
`modules can be designed to produce vibrational amplitude/
`frequency combinations throughouta large region of ampli-
`tude/frequency space.
`
`25
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIGS. 1A-B illustrate an unbalanced electric motor typi-
`cally used for generating vibrations in a wide variety of
`different devices.
`
`30
`
`FIGS. 2A-Billustrate the vibrational motion produced by
`the unbalanced electric motor shown in FIGS. 1A-B.
`
`FIG. 3 shows a graph of vibrational force with respect to
`frequency for various types of unbalanced electric motors.
`FIGS. 4A-G illustrate one particular LRVM,and opera-
`tion of the particular LRVM,that represents one implemen-
`tation of the linear-resonant vibration module to which
`
`35
`
`current application is directed.
`FIGS. 5A-B illustrate an H-bridge switch that can be
`used, in various embodiments of the current application, to
`change the direction of current applied to the coil that drives
`linear oscillation within a linear-resonance vibration module
`
`(“LRVM”).
`FIG.6 provides a block diagram of the LRVM,illustrated
`in FIGS. 4A-G, that represents one implementation of the
`linear-resonant vibration module to which current applica-
`tion is directed.
`FIGS. 7A-C provide control-flow diagramsthat illustrate
`the control program, executed by the CPU, that controls
`operation of an LRVM that represents one implementation
`of the linear-resonant vibration module to which current
`
`40
`
`45
`
`50
`
`application is directed shown in FIG. 16.
`
`24
`
`24
`
`

`

`US 9,941,830 B2
`
`10
`
`40
`
`45
`
`50
`
`5
`extremeright sides of the cylindrical chamber, the weightis
`repelled by one of the disk-like magnets at the left or right
`ends of the cylindrical chamber.In other words, the disk-like
`magnets act muchlike springs, to facilitate deceleration and
`reversal of direction of motion of the weight and to minimize
`or prevent mechanical-impact forces of the weight and the
`end caps that close off the cylindrical chamber.Finally, a coil
`of conductive wire 420 girdles the cylindrical housing, or
`tube 402 at approximately the mid-point of the cylindrical
`housing.
`FIGS. 4B-Gillustrate operation of the LRVM shown in
`FIG. 4A. Whenan electric current is applied to the coil 420
`in a first direction 422, a corresponding magnetic force 424
`is generated in a direction parallel to the axis of the cylin-
`drical chamber, which accelerates the weight 404 in the
`direction of the magnetic force 424. When the weight
`reaches a point at or close to the corresponding disk-like
`magnet 414, as shown in FIG. 4C, a magnetic force due to
`the repulsion of the disk-like magnet 414 and the weight
`404, 426, is generated in the opposite direction, decelerating
`the weight andreversing its direction. As the weight reverses
`direction, as shown in FIG. 4D, current is applied in an
`opposite direction 430 to the coil 420, producing a magnetic
`force 432 in an opposite direction from the direction of the
`magnetic force shown in FIG. 4B, which accelerates the
`weight 404 in a direction opposite to the direction in which
`the weight is accelerated in FIG. 4B. As shownin FIG.4E,
`the weight then movesrightward until, as shown in FIG.4F,
`the weight is decelerated, stopped, and then accelerated in
`the opposite direction by repulsion of the disk-like magnet
`416. An electrical current is then applied to the coil 420 in
`the samedirection 434 as in FIG. 4B, again accelerating the
`solid cylindrical mass in the same direction as in FIG. 4B.
`Thus, by a combination of a magnetic field with rapidly
`reversing polarity, generated by alternating the direction of
`current applied to the coil, and by the repulsive forces
`between the weight magnet and the disk-like magnets at
`each end of the hollow, cylindrical chamber,
`the weight
`linearly oscillates back and forth within the cylindrical
`housing 402, imparting a directional force at the ends of the
`cylindrical chamber with each reversal in direction.
`Clearly, the amplitude of the vibration and vibrational
`forces produced are related to the length of the hollow
`chamber in which the weight oscillates, the current applied
`to the coil, the mass of the weight, the acceleration of the
`weight produced by the coil, and the mass of the entire
`LRVM. All of these parameters are essentially design
`parameters for the LRVM, and thus the LRVM can be
`designed to produce a wide variety of different amplitudes.
`The frequency of the oscillation of the solid, cylindrical
`massis determined by the frequency at which the direction
`of the current applied to the coil is changed. FIGS. 5A-B
`illustrate an H-bridge switch that can be used, in various
`embodiments of the current application, to changethe direc-
`tion of current applied to the coil that drives linear oscilla-
`tion within an LRVM. FIGS. 5A-B both use the same
`
`illustration conventions, described next with respect to FIG.
`5A. The H-bridge switch receives, as input, a directional
`signal d 502 and direct-current (“DC”) power 504. The
`direction-control signal d 502 controls four switches 506-
`509, shownastransistors in FIG. 5A. Whenthe input control
`signal d 502 is high, or “1,” as shown in FIG. 5A, switches
`508 and 509 are closed and switches 506 and 507 are open,
`and therefore current flows, as indicated by curved arrows,
`such as curved arrow 510, from the power-source input 504
`to ground 512 in a leftward direction through the coil 514.
`Whenthe input-control signal d is low, or “0,” as shown in
`
`6
`FIG. 5B, the direction of the current through the coil is
`reversed. The H-bridge switch, shown in FIGS. 5A-B, is but
`one example of various different types of electrical and
`electromechanical switches that can be used to rapidly
`alternate the direction of current within the coil ofan LRVM.
`
`FIG.6 provides a block diagram of the LRVM,illustrated
`in FIGS. 4A-G, that represents one implementation of the
`linear-resonant vibration module to which current applica-
`tion is directed. The LRVM,in addition to the cylindrical
`housing, coil, and internal components shown in FIG. 4A,
`includes a power supply, a user interface, generally com-
`prising electromechanical buttons or switches, the H-bridge
`switch, discussed above with reference to FIGS. 5A-B, a
`central processing unit (“CPU”), generally a small,
`low-
`powered microprocessor, and one or more electromechani-
`cal sensors. All of these components are packaged together
`as an LRVM within a vibration-based appliance, device, or
`system.
`As shown in FIG. 6, the LRVM 600 is controlled by a
`control program executed by the CPU microprocessor 602.
`The microprocessor may contain suflicient on-board
`memory to store the control program and other values
`needed during execution of the control program, or, alter-
`natively, may be coupled to a low-powered memory chip
`604 or flash memory for storing the control program. The
`CPU receives inputs from the user controls 606 that together
`comprise a user interface. These controls may include any of
`various dials, pushbuttons, switches, or other electrome-
`chanical-control devices. As one example, the user controls
`may include a dial to select a strength of vibration, which
`corresponds to the current applied to the coil, a switch to
`select one of various different operational modes, and a
`powerbutton. The user controls generate signals input to the
`CPU 608-610. A power supply 612 provides power, as
`needed, to user controls 614, to the CPU 616 and optional,
`associated memory, to the H-bridge switch 618, and, when
`needed, to one or more sensors 632. The voltage and current
`supplied by the power supply to the various components
`may vary, depending on the operational characteristics and
`requirements of the components. The H-bridge switch 620
`receives a control-signal input d 622 from the CPU. The
`powersupply 612 receives a control input 624 from the CPU
`to control the current supplied to the H-bridge switch 618 for
`transfer to the coil 626. The CPU receives input 630 from
`one or more electromechanical sensors 632 that generate a
`signal corresponding to the strength of vibration currently
`being producedbythelinearly oscillating mass 634. Sensors
`may include one or more of accelerometers, piezoelectric
`devices, pressure-sensing devices, or other types of sensors
`that can generate signals corresponding to the strength of
`desired vibrational forces.
`FIGS. 7A-C provide control-flow diagramsthatillustrate
`the control program, executed by the CPU, that controls
`operation of an LRVM that represents one implementation
`of the linear-resonant vibration module to which current
`application is directed. FIG. 7A provides a control-flow
`diagram for the high-level control program. The program
`begins execution,
`in step 702, upon a power-on event
`invoked by a user through a power button or other user
`control. In step 702, various local variables are set to default
`values, including the variables: (1) mode, which indicates
`the current operational mode of the device; (2) strength, a
`numerical value corresponding to the current user-selected
`strength of operation, corresponding to the electrical current
`applied to the coil; (3) Ivl0, a previously sensed vibrational
`strength; (4) Ivl1, a currently sensed vibrational strength; (5)
`freq, the current frequency at which the direction of current
`
`25
`
`25
`
`

`

`US 9,941,830 B2
`
`7
`is alternated in the coil; (6) d, the control output to the
`H-bridge switch; and (7) inc, a Boolean value that indicates
`that the frequency is currently being increased. Next, in step
`704, the control program waits for a next event. The remain-
`ing steps represent a continuously executing loop, or event
`handler, in which each event that occurs is appropriately
`handled by the control program.In certain implementations
`of the control program, events may beinitiated by interrupt-
`like mechanisms and stacked for execution while, in more
`primitive implementations, certain events that overlap in
`time may be ignored or dropped. In the implementation
`illustrated in FIGS. 7A-C, two timers are used, one for
`controlling the change in direction of the current applied to
`the coil, at a currently established frequency, and the other
`for controlling a monitoring interval at which the control
`program monitors the vibrational force currently produced.
`Rather than using a formal timer mechanism,certain imple-
`mentations may simply employ counted loops or other
`simple programming techniques for periodically carrying
`out tasks. When an event occurs, the control program begins
`a series of tasks, the first of which is represented by the
`conditional step 706, to determine what event has occurred
`and appropriately handle that event. When the frequency
`timerhas expired, as determinedin step 706, the value of the
`output signal d is flipped, in step 708, and output to the
`H-bridge switch, with the frequency timer being reset to
`trigger a next frequency-related event. The frequency-timer
`interval is determined by the current value of the variable
`freq. Otherwise, when the event is a monitor timer expira-
`tion event, as determined in step 710, then a routine “moni-
`tor” is called in step 712. Otherwise, when the event
`corresponds to a change in the user input through the user
`interface, as determined in step 714, the routine “control”is
`called in step 716. Otherwise, when the event is a power-
`down event, as determined in step 718, resulting from
`deactivation of a power button by the user, then the control
`program appropriately powers downthe device, in step 720,
`and the control program terminates in step 722. Any other of
`various types of events that may occur are handled by a
`default event handler 724. These events may include various
`error conditions that arise during operation of the device.
`FIG. 7B provides a control-flow diagram for the routine
`“monitor,” called in step 712 of FIG. 7A. In step 730, the
`routine “monitor” converts the sensor input to an integer
`representing the current vibrational force produced by the
`LRVMandstores the integer value in the variable Iv11. Next,
`in step 732, the routine “monitor” determines whetheror not
`the LRVMis currently operating in the default mode. In the
`default mode, the LRVM uses continuous feedback control
`to optimize the vibrational force produced by the LRVM by
`continuously seeking to operate the LRVMat a fr