Method of driving a driving apparatus

Patent metadata

Field	Value
Publication number	US-10511237-B2
Application number	US-201715435040-A
Country	US
Kind code	B2
Filing date	Feb 16, 2017
Priority date	Sep 21, 2012
Publication date	Dec 17, 2019
Grant date	Dec 17, 2019

Abstract

The present invention provides a driving apparatus capable of suppressing the operation noise. A driving apparatus comprises a piezoelectric element expanding and contracting in accordance with a driving signal; a supporting shaft connected to said piezoelectric element; a movable body frictionally engaged with said supporting shaft and capable of moving along said supporting shaft; and a driving portion applying said driving signal including a first driving signal which moves said movable body towards a first direction to said piezoelectric element, wherein said driving portion can repeatedly apply said first driving signal against said piezoelectric element by taking a first time in between, and said first driving signal comprises a main driving waveform group which moves said movable body to said first direction, and a sub driving waveform group which is placed after said main driving waveform group by having a second rest time shorter than said first time in between.

First claim

What is claimed is:

1. A method of driving a driving apparatus, comprising:
expanding and contracting a piezoelectric element in accordance with a driving signal;
connecting a supporting shaft to said piezoelectric element;
frictionally engaging a movable body with said supporting shaft, the movable body being capable of moving along said supporting shaft; and
moving said movable body in a first direction towards said piezoelectric element by applying said driving signal including a first driving signal against said piezoelectric element, wherein said applying further comprises repeatedly applying said first driving signal against said piezoelectric element by taking a first rest time in between each repetition of said first driving signal, and
wherein said first driving signal comprises a main driving waveform group and a sub driving waveform group which is placed after said main driving waveform group by having a second rest time shorter than said first rest time in between said main driving waveform group and said sub driving waveform group.

2. The method of driving said driving apparatus as set forth in claim 1 , wherein said movable body has an engagement portion formed at one end part of a second direction which is approximately perpendicular to said first direction, and frictionally engaging with said supporting shaft, and
wherein said movable body has one ended supporting structure supported by said supporting shaft via said engagement portion.

3. The method of driving said driving apparatus as set forth in claim 1 , wherein said sub driving waveform group includes a waveform, the method further comprising:
moving said movable body in said first direction by applying said waveform against said piezoelectric element, and
when a vibration period T is caused in said movable body while said movable body is stopped, then said second rest time is shorter than T/4.

4. The method of driving said driving apparatus as set forth in claim 1 , wherein said sub driving waveform group includes a waveform, the method further comprising:
moving said movable body in an opposite direction against said first direction by applying said waveform against said piezoelectric element, and
when a vibration period T is caused in said movable body while said movable body is stopped, then said second rest time is longer than T/4 and shorter than 3T/4.

5. The method of driving said driving apparatus as set forth in claim 1 , wherein said sub driving waveform group has a first sub driving waveform group which is placed after said main driving waveform group by having said second rest time in between said main driving waveform group and said first sub driving waveform group, and
a second sub driving waveform group which is placed after said first sub driving waveform group by having a third rest time shorter than said first time in between said first sub driving waveform group and said second sub driving waveform group.

6. The method of driving said driving apparatus as set forth in claim 5 , wherein said second sub driving waveform group includes a waveform, the method further comprising:
moving said movable body in a same direction that said first sub driving waveform group moves said movable body by applying said waveform against said piezoelectric element, and
when a vibration period T is caused in said movable body while said movable body is stopped, then said third rest time is shorter than T/4.

7. The method of driving said driving apparatus as set forth in claim 5 , wherein said second sub driving waveform group includes a waveform, the method further comprising:
moving said movable body in an opposite direction than said first sub driving waveform group moves said moveable body by applying said waveform against said piezoelectric element, and
when a vibration period T is caused in said movable body while said movable body is stopped, then said third rest time is longer than T/4 and shorter than 3T/4.

8. A method of driving a driving apparatus, comprising:
expanding and contracting a piezoelectric element in accordance with a driving signal;
connecting a supporting shaft to said piezoelectric element;
frictionally engaging a movable body with said supporting shaft, said movable body being capable of moving along said supporting shaft; and
moving said movable body in a first direction towards said piezoelectric element by applying said driving signal including a first driving signal against said piezoelectric element, wherein said applying further comprises repeatedly applying said first driving signal against said piezoelectric element by taking a first rest time in between each repetition of said first driving signal,
wherein said first driving signal comprises a main driving waveform group and a sub driving waveform group which is placed after said main driving waveform group by having a second rest time shorter than said first rest time in between said main driving waveform group and said sub driving waveform group,
wherein said sub driving waveform group includes a waveform which moves said movable body in said first direction, and when a vibration period T is caused in said movable body while said movable body is stopped, then said second rest time is shorter than T/4,
wherein said sub driving waveform group has a first sub driving waveform group which is placed after said main driving waveform group by having said second rest time in between said main driving waveform group and said first sub driving waveform group, and
a second sub driving waveform group is placed after said first sub driving waveform group by having a third rest time shorter than said first rest time in between said first sub driving waveform group and said second sub driving waveform group.

9. The method of driving said driving apparatus as set forth in claim 8 , wherein said second sub driving waveform group includes a waveform, the method further comprising:
moving said movable body in a same direction that said first sub driving waveform group moves said movable body by applying said waveform against said piezoelectric element, and
when said vibration period T is caused in said movable body while said movable body is stopped, then said third rest time is shorter than T/4.

10. The method of driving said driving apparatus as set forth in claim 9 , wherein said second sub driving waveform group includes a waveform, the method further comprising:
moving said movable body moves in an opposite direction than said first sub driving waveform group moves said movable body by applying said waveform against said piezoelectric element, and
when said vibration period T is caused in said movable body while said movable body is stopped, then said third rest time is longer than T/4 and shorter than 3T/4.

11. A method of driving a driving apparatus, comprising;
expanding and contracting a piezoelectric element in accordance with a driving signal;
connecting a supporting shaft to said piezoelectric element;
frictionally engaging a movable body with said supporting shaft, the movable body being capable of moving along said supporting shaft; and
moving said movable body in a first direction towards said piezoelectric element by applying said driving signal including a first driving signal against said piezoelectric element, wherein said applying further comprises repeatedly applying said first driving signal against said piezoelectric element by taking a first rest time in between each repetition of said first driving signal,
wherein said first driving signal comprises a main driving waveform group and a sub driving waveform group which is placed after said main driving waveform group by having a second rest time sho

Assignees

• Tdk Corp

Inventors

• Suzuki Akira
• Uno Masaru
• Imi Kazutomo
• Haga Yoshiaki

Classifications

• H02N2/025

  Inertial sliding motors · CPC title

• B06B1/0644

  using a single piezoelectric element (B06B1/0688 takes precedence) · CPC title

• H02N2/06 Primary

  Drive circuits; Control arrangements {or methods} · CPC title

• H02N2/062

  Small signal circuits; Means for controlling position or derived quantities, e.g. for removing hysteresis · CPC title