EP0112454A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Rotary actuator
Assignee: Hitachi Ltd
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Filing: 1983-10-21
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Granted: —
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Expires: 2003-10-21
Abstract
Abstract A rotary actuator for converting electrical energy into rotating torque comprises a stator (1), a rotor (2), a pair of annular first piezoelectric elements (5, 6) contracting and expanding in the radial direction in response to the application of an electrical signal, and a plurality of second piezoelectric elements (11, 12) disposed between the first piezoelectric elements (5, 6) and a holding portion (4) of the stator (1) for causing displacement of the first piezoelectric elements in the circumferential direction in response to the application of the electrical signal. These piezoelectric elements (5, 6, 11, 12) are alternately energized to continuously rotate the rotor (2).
Inventors
- 👤 Kenji Mori
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 00:38
CPC Classifications
H; H02; H02N; H02N2/00; H02N2/10; H02N2/101
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
121 words
A rotary actuator for converting electrical energy into rotating torque comprising: a stator (1); a rotor (2) supported by said stator so as to be rotatable relative to said stator; a holding member (4) provided on said stator so as to extend toward said rotor; annular first drive means (5, 6) disposed on both sides of said holding member for clamping and releasing said rotor by making expansive and contractive deformations in the radial direction thereof; second drive means (11, 12) disposed between and fixed to said first drive means and said holding member for causing rotary movement of said first drive means around said rotor; and means (301) for applying an energizing voltage to said first and second drive means.
Claim 2
Dependent Claim
121 words
A rotary actuator for converting electrical energy into rotating torque comprising: a stator (1); a rotor (2) supported by said stator so as to be rotatable relative to said stator; a holding member (4) provided on said stator so as to extend toward said rotor; annular first drive means (5, 6) disposed on both sides of said holding member for clamping and releasing said rotor by making expansive and contractive deformations in the radial direction thereof; second drive means (11, 12) disposed between and fixed to said first drive means and said holding member for causing rotary movement of said first drive means around said rotor; and means (301) for applying an energizing voltage to said first and second drive means.
Claim 3
Dependent Claim
64 words
A rotary actuator as claimed in Claim 1, wherein said stator is a cylindrical body (1), said rotor is a shaft (2) inserted into said cylindrical body to be rotatably supported by said cylindrical body, and said holding member (4) extends from said cylindrical body toward said shaft for holding said second drive means (11, 12) coupled to said first drive means (5, 6).
Claim 4
Dependent Claim
41 words
A rotary actuator as claimed in Claim 2, wherein said first drive means includes annular piezoelectric elements (5, 6) and a pair of electrodes (7A, 7B; 8A, 8B) provided on the inner and outer peripheries of each of said piezoelectric elements.
Claim 5
Dependent Claim
53 words
A rotary actuator as claimed in Claim 3, wherein said second drive means includes piezoelectric elements (11, 12) of shearing strain type and a pair of electrodes (9A, 9B; 10A, 10B) provided on each of said piezoelectric elements to extend in a direction parallel to the direction of polarization of said piezoelectric element.
Claim 6
Dependent Claim
31 words
A rotary actuator as claimed in Claim 3, wherein said second drive means includes piezoelectric elements (13) of bimorph type making a deflective deformation in response to a voltage applied thereto.
Claim 7
Dependent Claim
41 words
A rotary actuator as claimed in Claim 4, wherein at least one of said annular piezoelectric elements (5, 6) constituting said first drive means acts to still clamp said rotor (2) due to a contractive strain persisting after it is deenergized.
Claim 8
Dependent Claim
40 words
A rotary actuator as claimed in Claim.5, wherein at least one of said annular piezoelectric elements (5, 6) constituting said first drive means acts to still clamp said rotor (2) due to a contractive strain persisting after it is deenergized.
Claim 9
Dependent Claim
65 words
A rotary actuator as claimed in Claim 1, wherein said stator is a shaft (2), said rotor is a cylindrical body (1) surrounding said shaft to be rotatably supported by said shaft, and said holding member (14) extends from said shaft toward the inner periphery of said cylindrical body for holding said second drive means (11, 12) coupled to said first drive means (5, 6).
Claim 10
Dependent Claim
41 words
A rotary actuator as claimed in Claim 8, wherein said first drive means includes annular piezoelectric elements (5, 6) and a pair of electrodes (7A, 7B; 8A, 8B) provided on the inner and outer peripheries of each of said piezoelectric elements.
Claim 11
Dependent Claim
53 words
A rotary actuator as claimed in Claim 9, wherein said second drive means includes piezoelectric elements (11, 12) of shearing strain type and a pair of electrodes (9A, 9B; 10A, 10B) provided on each of said piezoelectric elements to extend in a direction parallel to the direction of polarization of said piezoelectric element.
Claim 12
Dependent Claim
31 words
A rotary actuator as claimed in Claim 9, wherein said second drive means includes piezoelectric elements (13) of bimorph type making a deflective deformation in response to a voltage applied thereto.
Claim 13
Dependent Claim
41 words
A rotary actuator as claimed in Claim 10, wherein at least one of said annular piezoelectric elements (5, 6) constituting said first drive means acts to still clamp said rotor (1) due to a tensile strain persisting after it is deenergized.
Claim 14
Dependent Claim
41 words
A rotary actuator as claimed in Claim 11, wherein at least one of said annular piezoelectric elements (5, 6) constituting said first drive means acts to still clamp said rotor (1) due to a tensile strain persisting after it is deenergized.
References Cited (Backward Citations)
No citation records indexed.
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