Driving apparatus of vibration type actuator
AssigneeCanon Kabushiki Kaisha
InventorsTadashi Hayashi, Shinji Yamamoto
Life of this patent
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Abstract
A driving apparatus of a vibration type actuator includes an apparatus for forming a vibration wave by applying four-phase AC signals having temporal phase differences to four-phase driving phases arranged at intervals of ¼ wavelength, which includes first and second transformers and two-phase driving phases connected to the secondary terminals of the respective transformers, thereby simplifying the arrangement of a driving circuit.
Claims21
A driving apparatus of a four-phase driving vibration type actuator for applying four-phase AC signals having temporal phase differences to four-phase driving phases arranged on an electro-mechanical energy conversion element of a vibration member at intervals of ¼ wavelength of a resonance vibration, thereby forming a traveling wave by synthesizing a standing wave formed by one pair of two-phase driving phases at a position of a half wavelength with a standing wave formed by the other pair of two-phase driving phases, comprising:
- a pulse signal generating circuit for generating a pulse signal in accordance with a driving frequency;
- a first switching circuit for outputting an AC voltage to a first transformer by ON/OFF-controlling a switching element in accordance with the pulse signal output by said pulse signal generating circuit;
- and
- a second switching circuit for outputting an AC voltage to a second transformer by ON/OFF-controlling the switching element in accordance with the pulse signal output by said pulse signal generating circuit,
- wherein each phase of said one pair of two-phase driving phases respectively is connected to one of two ends of a secondary side of the first transformer, each phase of said other pair of two-phase driving phases respectively is connected to one of two ends of a secondary side of the second transformer, and said pulse signal generating circuit outputs to said first and second switching circuits pulse signals having a phase difference of 90°.
A driving apparatus of a vibration type actuator for generating a standing wave by applying an AC signal to an electro-mechanical energy conversion element of a vibration member, comprising:
- a transformer for outputting an AC voltage;
- and
- an inductor formed on a secondary side of said transformer, said transformer being set to satisfy
- fr<(fre/2)<fs
- where fre is a parallel resonance frequency of an inductance of said inductor and a capacitance of the electro-mechanical energy conversion element, fr is a resonance frequency of the vibration member, and fs is a frequency at which a vibration amplitude of the vibration member increases for the first time in a region higher than the resonance frequency fr.
A driving apparatus of a vibration type actuator for generating a standing wave by applying two-phase AC signals having a temporal phase difference of 180° to two-phase driving phases arranged on an electro-mechanical energy conversion element of a vibration member at intervals of ½ wavelength of resonance vibrations, comprising:
- a transformer for outputting an AC voltage, said transformer including two inductors on a secondary side of said transformer to drive two-phase driving phases, and being set to satisfy
- fr<(fre/2)<fs
- where fre is a parallel resonance frequency of an inductance of one of said inductors and a capacitance of one phase of the electro-mechanical energy conversion element, fr is a resonance frequency of the vibration member, and fs is a frequency at which a vibration amplitude of the vibration member increases for the first time in a region higher than the resonance frequency fr.
A driving apparatus of a vibration type actuator for generating a standing wave by applying an AC signal to an electro-mechanical energy conversion element of a vibration member, comprising:
- a transformer for outputting an AC voltage;
- and
- an inductor formed, on a secondary side of said transformer, said transformer being set to satisfy
- fr<(fre/2)<fs
- where fre is a parallel resonance frequency of an inductance of the inductor and a sum of a capacitance of the electro-mechanical energy conversion element and a capacitance of an adjustment capacitor, fr is a resonance frequency of the vibration member, and fs is a frequency at which a vibration amplitude of the vibration member increases for the first time in a region higher than the resonance frequency fr.
A driving apparatus of a vibration type actuator for generating a standing wave by applying two-phase AC signals having a temporal phase difference of 180° to two-phase driving phases arranged on an electro-mechanical energy conversion element of a vibration member at intervals of ½ wavelength of resonance vibrations, comprising:
- a transformer for outputting an AC voltage, said transformer including two inductors on a secondary side of said transformer to drive two-phase driving phases and an adjustment capacitor added thereto, said transformer being set to satisfy
- fr<(fre/2)<fs
- where fre is a parallel resonance frequency of an inductance of one of said two inductors and a sum of a capacitance of one phase of the electro-mechanical energy conversion element and a capacitance of the adjustment capacitor connected to said one phase of the electro-mechanical energy conversion element, fr is a resonance frequency of the vibration member, and fs is a frequency at which a vibration amplitude of the vibration member increases for the first time in a region higher than the resonance frequency fr.
A driving apparatus of a vibration driving type actuator for forming a traveling wave by synthesizing a standing wave formed by one pair of two-phase driving phases with a standing wave formed by the other pair of two-phase driving phases, each standing wave having a positional relationship relative to the other standing wave represented by a half wavelength with respect to a wavelength of resonance vibrations, by applying four-phase AC signals having temporal phase differences from each other to four-phase driving phases arranged on an electro-mechanical energy conversion element of a vibration member at intervals of ¼ wavelength of the resonance vibrations, comprising:
- first and second transformers for generating AC voltages, said first and second transformers respectively having two inductors formed on secondary sides thereof to drive two-phase driving phases, and being set to satisfy
- fr<(fre/2)<fs
- where fre is a parallel resonance frequency of an inductance of one of said inductors and a capacitance of one phase of the electro-mechanical energy conversion element, fr is a resonance frequency of the vibration member, and fs is a frequency at which a vibration amplitude of the vibration member increases for the first time in a region higher than the resonance frequency fr.
A driving apparatus of a vibration type actuator for forming a traveling wave by synthesizing a standing wave formed by one pair of two-phase driving phases with a standing wave formed by the other pair of two-phase driving phases, each standing wave having a positional relationship relative to the other standing wave represented by a half wavelength with respect to a wavelength of resonance vibrations, by applying four-phase AC signals having temporal phase differences from each other to four-phase driving phases arranged on an electro-mechanical energy conversion element of a vibration member at intervals of ¼ the wavelength of resonance vibrations, comprising:
- first and second transformers for generating AC voltages, said first and second transformers respectively including two inductors formed on secondary sides thereof to drive two-phase driving phases and adjustment capacitors added thereto, said first and second transformers being set to satisfy
- fr<(fre/2)<fs
- where fre is a parallel resonance frequency of an inductance of one of said inductors and a sum of a capacitance of one phase of the electro-mechanical energy conversion element and a capacitance of an adjustment capacitor connected to said one phase of the electro-mechanical energy conversion element, fr is a resonance frequency of the vibration member, and fs is a frequency at which a vibration amplitude of the vibration member increases for the first time in a region higher than the resonance frequency fr.
A driving apparatus of a vibration type actuator for generating a standing wave by applying an AC signal to an electro-mechanical energy conversion element of a vibration member, comprising:
- a transformer for outputting an AC voltage, said transformer including a first inductor on a secondary side connected to a predetermined phase of said electro-mechanical energy conversion element and a second inductor connected to a phase of said electro-mechanical energy conversion element shifted from said predetermined phase by 180°, said transformer being set to satisfy
- fr<(fre/2)<fs
- wherein fre is a parallel resonance frequency of an inductance of said first inductor and a capacitance of said predetermined phase of said electro-mechanical energy conversion element, or a parallel resonance frequency of an inductance of said second inductor and a capacitance of said phase of said electro-mechanical energy conversion element shifted from said predetermined phase by 180°, fr is a resonance frequency of said vibration member, and fs is a frequency at which a vibration amplitude of said vibration member increases for the first time in a region higher than said resonance frequency fr.
A driving apparatus of a vibration type actuator for generating a standing wave by applying an AC signal to an electro-mechanical energy conversion element of a vibration member, comprising:
- a transformer for outputting an AC voltage;
- a first adjustment capacitor connected to a first phase of said electro-mechanical energy conversion element;
- and
- a second adjustment capacitor connected to a second phase of said electro-mechanical energy conversion element and shifted from said first phase by 180°,
- wherein said transformer includes a first inductor on a secondary side connected to the first phase of said electro-mechanical energy conversion element and a second inductor connected to the second phase of said electro-mechanical energy conversion element, said transformer being set to satisfy
- fr<(fre/2)<fs
- wherein fre is a parallel resonance frequency of an inductance of said first inductor and a sum of a capacitance of said first phase of said electro-mechanical energy conversion element and a capacitance of said first adjustment capacitor, or a parallel resonance frequency of an inductance of said second inductor and a sum of a capacitance of said second phase of said electro-mechanical energy conversion element and a capacitance of said second adjustment capacitor, fr is a resonance frequency of said vibration member, and fs is a frequency at which a vibration amplitude of said vibration member increases for the first time in a region higher than said resonance frequency fr.
Dependencies are inferred from the claim text.