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US8203253B2 Active / In Force US ⏱️ 2.0 years remaining

Piezoelectric actuator, driving device, positioning device and laser module

Assignee: Konica Minolta Opto Inc
•
Filing: 2008-11-19
•
Granted: 2012-06-19
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Expires: 2028-11-19
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Abstract

Abstract In a piezoelectric actuator ( 8 ) comprising a layered piezoelectric element ( 14 ) which consists of alternately stacked expansion and contraction layers ( 14 a ) and electrode layers ( 14 b ), a driving shaft ( 15 ) of which one end is fixed to one end of the piezoelectric element ( 14 ) in expansion and contraction direction, a movable member ( 15 ) frictionally engaging with the driving shaft ( 15 ) and a collar ( 17 ) bonded to the circumference of the piezoelectric element ( 14 ), by bonding the collar ( 17 ) to the circumference of the plurality of the expansion and contraction layers ( 14 a ) with an adhesive (G) so that fastening force of the collar ( 17 ) to the expansion and contraction layers ( 14 a ) is imbalanced with reference to the center of the cross section of the piezoelectric element ( 14 ) so that the piezoelectric element ( 14 ) expands and contracts in an imbalanced manner to incline the driving shaft ( 15 ) to displace minutely the movable member ( 16 ).

Inventors

  • 👤 Kazuhiro Shibatani

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 21:21
CPC Classifications
H; H02; H02N; H02N2/00; H02N2/02; H02N2/021; H02N2/025; H01; H01S; H01S5/00; H01S5/06; H01S5/068; H01S5/0683; H02N2/06; H02N2/065; H02N2/067; H01S5/005; H01S5/0071; H01S5/0092; H01S5/06821

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 107 words
A piezoelectric actuator comprising a layered piezoelectric element which consists of alternately stacked expansion and contraction layers and electrode layers, a driving shaft which is displaced by the piezoelectric element in expansion and contraction direction, a movable member frictionally engaging with the driving shaft and a collar bonded to the circumference of the piezoelectric element, wherein the collar is bonded to a plurality of the expansion and contraction layers so that the fastening force of the collar to the expansion and contraction layers is imbalanced with reference to the center of the cross section perpendicular to the direction of the expansion and contraction of the piezoelectric element.
Claim 2
Dependent Claim 107 words
A piezoelectric actuator comprising a layered piezoelectric element which consists of alternately stacked expansion and contraction layers and electrode layers, a driving shaft which is displaced by the piezoelectric element in expansion and contraction direction, a movable member frictionally engaging with the driving shaft and a collar bonded to the circumference of the piezoelectric element, wherein the collar is bonded to a plurality of the expansion and contraction layers so that the fastening force of the collar to the expansion and contraction layers is imbalanced with reference to the center of the cross section perpendicular to the direction of the expansion and contraction of the piezoelectric element.
Claim 3
Dependent Claim 24 words
The piezoelectric actuator according to claim 1 , wherein the collar is not bonded partially to the circumference of the expansion and contraction layers.
Claim 4
Dependent Claim 27 words
The piezoelectric actuator according to claim 1 , wherein the collar is bonded to the expansion and contraction layers with partially different adhesives having different Young's modulus.
Claim 5
Dependent Claim 31 words
The piezoelectric actuator according to claim 1 , wherein the piezoelectric element has a circumference shaped in a rectangular form and one side of the circumference is bonded to the collar.
Claim 6
Dependent Claim 31 words
The piezoelectric actuator according to claim 1 , wherein the piezoelectric element has a circumference shaped in a rectangular form and three side of the circumference are bonded to the collar.
Claim 7
Dependent Claim 30 words
The piezoelectric actuator according to claim 1 , wherein the piezoelectric element has a circumference shaped in a circular form and the collar is bonded half around the piezoelectric element.
Claim 8
Dependent Claim 28 words
The piezoelectric actuator according to claim 1 , wherein the collar is at least partially open viewed from the center of the cross section of the piezoelectric element.
Claim 9
Dependent Claim 25 words
The piezoelectric actuator according to claim 1 , wherein the collar has a hole in which the piezoelectric element and the driving shaft are inserted.
Claim 10
Dependent Claim 23 words
The piezoelectric actuator according to claim 1 , wherein the collar supports the bonded portion of the piezoelectric element and the driving shaft.
Claim 11
Dependent Claim 36 words
The piezoelectric actuator according to claim 1 , wherein the working point of the movable member is offset from the driving shaft in a direction in which the fastening force of the collar is most imbalance.
Claim 12
Dependent Claim 81 words
A driving device comprising the piezoelectric actuator according to claim 1 , and a driving circuit capable of applying a dynamic driving voltage and a static driving voltage to the piezoelectric element of the piezoelectric actuator, wherein the dynamic driving voltage causes the driving shaft of the piezoelectric actuator to reciprocate asymmetrically so as to displace slidingly the movable member, and the static driving voltage causes the driving shaft to move slowly so as not to displace slidingly the movable member.
Claim 13
Dependent Claim 25 words
The driving device according to claim 11 , wherein the static driving voltage is a cyclic voltage having lower frequency than the dynamic driving voltage.
Claim 14
Dependent Claim 88 words
A positioning device comprising the driving device according to claim 11 , a displacement detector outputting a displacement output which peaks when the movable member of the driving device is locating at a predetermined position, and comes lower with the movable member being further from the predetermined position, and a controller which determines the applying amount of the dynamic driving voltage based on a variation of the displacement output while a movement of the movable member with the static driving voltage, so as to maximize the displacement output.
Claim 15
Dependent Claim 69 words
A laser module comprising the positioning device according to claim 13 and a light receiving member receiving laser light and outputting the laser light, wherein the displacement detector of the positioning device is a sensor which detects the output power of the light receiving member and the movable member of the positioning device is an optical member which position the laser light with respect to the light receiving member.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2015-06-19 2015-12-19 2016-06-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2019-06-19 2019-12-19 2020-06-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2023-06-19 2023-12-19 2024-06-19 $7700.00 Window Closed / Lapsed

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