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US5157300A Expired / Lapsed US ⏱️ 0.0 years remaining

Vibration wave driven motor apparatus

Assignee: Canon Inc
•
Filing: 1991-01-07
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Granted: 1992-10-20
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Expires: 2011-01-07
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Abstract

Abstract This specification discloses a vibration wave driven motor in which frequency signals differing in phase from each other are applied to an electro-mechanical energy conversion element on a vibration member to thereby form a travelling vibration wave and a movable member is driven by the travelling vibration wave. The value of a factor which determines the natural frequency of the resonance system of the motor including a driven member when the driven member is driven by the motor or the frequency of wow-flutter is set so that the frequency of wow-flutter may not coincide with the natural frequency, thereby minimizing the unnecessary vibration of the driven member.

Inventors

  • 👤 Kenichi Kataoka
  • 👤 Koji Kitani

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 19:56
CPC Classifications
H; H02; H02N; H02N2/00; H02N2/10; H02N2/14; H02N2/142; H02N2/12; H02N2/123

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 119 words
A motor control system for driving a driven member of a vibration wave driven motor, said motor including an elastic vibration member and an electro-mechanical energy conversion element portion provided on said elastic member and in which frequency signals differing in phase from each other are applied to thereby excite a plurality of standing waves therein, said standing waves combining to form a travelling vibration wave as a drive force, said system including: a factor which determines a natural frequency of a resonance system including said driven member and a factor which determines a frequency of wow-flutter, said factors being set so that said natural frequency and said frequency of wow-flutter may not coincide with or approximate each other.
Claim 2
Dependent Claim 119 words
A motor control system for driving a driven member of a vibration wave driven motor, said motor including an elastic vibration member and an electro-mechanical energy conversion element portion provided on said elastic member and in which frequency signals differing in phase from each other are applied to thereby excite a plurality of standing waves therein, said standing waves combining to form a travelling vibration wave as a drive force, said system including: a factor which determines a natural frequency of a resonance system including said driven member and a factor which determines a frequency of wow-flutter, said factors being set so that said natural frequency and said frequency of wow-flutter may not coincide with or approximate each other.
Claim 3
Dependent Claim 40 words
A motor control system according to claim 1, wherein said frequency of wow-flutter is found from 2·A·N, where A is an integer and N is a driving speed, and wherein N is the factor which determines said frequency of wow-flutter.
Claim 4
Dependent Claim 71 words
A motor control system according to claim 1, wherein said frequency of wow-flutter is found from A·S·T·N (where T is an even number) or 2·A·S·T·N (where T is an odd number), where S is a wave number of the travelling vibration wave, T is the number of standing waves combined, and N is a driving speed, and wherein S, T or N is the factor which determines the frequency of wow-flutter.
Claim 5
Dependent Claim 66 words
A motor control system according to claim 1, wherein a surface of said elastic member is formed with substantially equally spaced-apart slits or projection, wherein said frequency of wow-flutter is found from A·M·N, where A is an integer, M is the number of slits or projections, and N is a driving speed, and wherein M or N is the factor which determines said frequency of wow-flutter.
Claim 6
Dependent Claim 40 words
A motor control system according to claim 1, wherein said frequency of wow-flutter is found from A·N, where A is an integer and N is a driving speed, and wherein N is the factor which determines said frequency of wow-flutter.
Claim 7
Dependent Claim 48 words
A motor control system according to claim 1, wherein said frequency of wow-flutter is found from 2·A·S·N, where S is a wave number of the travelling vibration wave and N is a driving speed, and wherein S or N is the factor which determines said frequency of wow-flutter.
Claim 8
Dependent Claim 72 words
A motor control system according to claim 1, wherein said frequency of wow-flutter is found from A·V·T/R (where T is an even number) or 2·A·V·T/R (where T is an odd number), where V is a relative speed of the motor, T is the number of standing waves, and R is a wavelength of the travelling vibration wave, and wherein V, T or R is the factor which determines said frequency of wow-flutter.
Claim 9
Dependent Claim 66 words
A motor control system according to claim 1, wherein a surface of said elastic member is formed with substantially equally spaced-apart slits or projections, wherein said frequency of wow-flutter is found from A·V/L, where V is a relative speed of the motor, and L is a spacing between the slits or projections, and wherein V or L is the factor which determines said frequency of wow-flutter.
Claim 10
Dependent Claim 50 words
A motor control system according to claim 1, wherein said frequency of wow-flutter is found from 2·A·V/R, where V is a relative speed of the motor and R is a wavelength of the travelling vibration wave, and wherein V or R is the factor which determines said frequency of wow-flutter.
Claim 11
Dependent Claim 89 words
A motor control system for driving a driven member of a vibration motor, said vibration motor including an electro-mechanical energy conversion element portion in which frequency signals differing in phases from each other are applied to produce therein a vibration as a driving force, said system comprising: a factor which determines a natural frequency of a resonance system and a factor which determines a frequency of wow-flatter, said factors being set so that said natural frequency and said frequency of wow-flutter may not coincide with or approximate each other.
Claim 12
Dependent Claim 89 words
A motor control system for driving a driven member of a vibration motor, said vibration motor including an electro-mechanical energy conversion element portion in which frequency signals differing in phases from each other are applied to produce therein a vibration as a driving force, said system comprising: a factor which determines a natural frequency of a resonance system and a factor which determines a frequency of wow-flatter, said factors being set so that said natural frequency and said frequency of wow-flutter may not coincide with or approximate each other.
Claim 13
Dependent Claim 40 words
A motor control system according to claim 10, wherein said frequency of wow-flutter is found from 2·A·N, where A is an integer and N is a driving speed, and wherein N is the factor which determines said frequency of wow-flutter.
Claim 14
Dependent Claim 61 words
A motor control system according to claim 10, further comprising an elastic member, a surface of said elastic member being formed with substantially equally spaced-apart slits or projections, wherein said frequency of wow-flutter found from A·M·N, where A is an integer and M is a driving speed, and wherein M or N is the factor which determines said frequency of wow-flutter.
Claim 15
Dependent Claim 40 words
A motor control system according to claim 10, wherein said frequency of wow-flutter is found from A·N, where A is an integer and N is a driving speed, and wherein N is the factor which determines said frequency of wow-flutter.
Claim 16
Dependent Claim 74 words
A motor control system according to claim 10, further comprising an elastic member, a surface of said elastic member being formed with substantially equally spaced-apart slits or projections, wherein said frequency of wow-flutter is found from A·V/L, where A is an integer, V is a relative speed of the motor, and L is a spacing between the slits or projections, and wherein V or L is the factor which determines said frequency of wow-flutter.
Claim 17
Dependent Claim 55 words
A motor control system for a vibration motor, said system comprising: setting means for setting motor speed; and a prohibition circuit for prohibiting the driving of the motor at a speed set by said setting means when a wow-flutter frequency of the motor rotating in the set speed coincides with or approximates a natural frequency.
Claim 18
Dependent Claim 55 words
A motor control system for a vibration motor, said system comprising: setting means for setting motor speed; and a prohibition circuit for prohibiting the driving of the motor at a speed set by said setting means when a wow-flutter frequency of the motor rotating in the set speed coincides with or approximates a natural frequency.
Claim 19
Dependent Claim 26 words
A motor according to claim 15, wherein said prohibition circuit rotates the motor at a speed close to the set speed instead of the set speed.

References Cited (Backward Citations)

US4743788A Cited
EP0261810A2 Cited
US4914337A Cited
US5032753A Cited
US5004964A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-10-20 1996-04-20 1996-10-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-10-20 2000-04-20 2000-10-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-10-20 2004-04-20 2004-10-20 $7700.00 Window Closed / Lapsed

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