EP0424139A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Ultrasonic motor
Assignee: Seiko Epson Corp
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Filing: 1990-10-18
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Granted: —
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Expires: 2010-10-18
Abstract
Abstract An ultrasonic motor comprising a stator (2); a vibrator (3) for oscillating the stator (2); and a rotor (1) which is arranged to make contact with the stator (2) so as to be driven thereby by frictional force characterised in that the rotor (1) has a plurality of projections (1a-1d) which are spaced from each other and which in operation make contact with the stator (2).
Inventors
- 👤 Osamu C/O Seiko Epson Corporation Miyazawa
- 👤 Kiyoto C/O Seiko Epson Corporation Takeda
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 23:37
CPC Classifications
H; H02; H02N; H02N2/00; H02N2/10; H02N2/16; H02N2/166; H02N2/0005; H02N2/001; H02N2/0015; H02N2/0075; H02N2/0085; H02N2/103
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
68 words
An ultrasonic motor comprising a stator (2) provided with a vibrator (3) for oscillating the stator (2); and a rotor (1) which is arranged to make contact with the stator (2) so as to be driven thereby by frictional force characterised in that the rotor (1) has a plurality of projections (1a-1d) which are spaced from each other and which in operation make contact with the stator (2).
Claim 2
Dependent Claim
68 words
An ultrasonic motor comprising a stator (2) provided with a vibrator (3) for oscillating the stator (2); and a rotor (1) which is arranged to make contact with the stator (2) so as to be driven thereby by frictional force characterised in that the rotor (1) has a plurality of projections (1a-1d) which are spaced from each other and which in operation make contact with the stator (2).
Claim 3
Dependent Claim
39 words
An ultrasonic motor as claimed in claim 1 characterised in that the motor is provided with at least one drive control apparatus (103,106) for impressing waves on a plurality of vibrating devices (107) which form the said vibrator (108).
Claim 4
Dependent Claim
44 words
An ultrasonic motor as claimed in claim 2 characterised in that the said waves are standing waves, the drive control apparatus (103,106) having means (106) for changing the phases of the waves supplied to the individual vibrating devices or for effecting ON-OFF operation thereof.
Claim 5
Dependent Claim
38 words
An ultrasonic motor as claimed in claim 3 characterised in that the drive control apparatus (103,106) is arranged to induce standing waves of a wavelength λ whose nodes are shifted by a given distance (L) at a time.
Claim 6
Dependent Claim
19 words
An ultrasonic motor as claimed in claim 4 characterised in that the given distance (L) is less than λ/4.
Claim 7
Dependent Claim
51 words
An ultrasonic motor as claimed in claim 3 characterised in that the said drive control apparatus (103,106) displaces the positions of n nodes of a disc-like or ring-like stator (2) which oscillates in a vibration mode of standing waves, the nodes shifting by ϑ° at a time such that ϑ°< 90°/n.
Claim 8
Dependent Claim
69 words
An ultrasonic motor as claimed in any of claims 3-6, characterised in that, in addition to the first-mentioned drive control apparatus (103b) for producing standing waves, there is a second drive control apparatus (304) for impressing advancing waves on the vibrator (3) so as to continuously drive the rotor (1), a change-over circuit (305) being provided for changing over between the first mentioned and second drive control apparatuses (103b,304).
Claim 9
Dependent Claim
21 words
An ultrasonic motor as claimed in any preceding claim characterised in that the rotor (1) comprises a resilient member or members.
Claim 10
Dependent Claim
55 words
An ultrasonic motor as claimed in any preceding claim characterised in that the rotor projections (1a-1d) have sliding faces (34) which are arranged to contact a part or parts (2a) the stator (2), the sliding faces (34) and/or the said part or parts (2a) having slanting or curved relieved portions (32,33,35,36) to reduce interference therebetween.
Claim 11
Dependent Claim
33 words
An ultrasonic motor as claimed in any preceding claim characterised in that the stator (2) has a plurality of projections (2a) which are adapted to come into contact with the rotor projections (1a-1d).
Claim 12
Dependent Claim
25 words
An ultrasonic motor as claimed in claim 10 characterised in that the stator projections (2d) extend radially outwardly from the circumference of the stator (2).
Claim 13
Dependent Claim
30 words
An ultrasonic motor as claimed in claim 11 characterised in that the stator projections (2d) are disposed at places which do not in operation become vibration nodes of the stator.
Claim 14
Dependent Claim
21 words
An ultrasonic motor as claimed in any preceding claim characterised in that the vibrator comprises at least one piezo-electric element (3).
Claim 15
Dependent Claim
55 words
An ultrasonic motor as claimed in claim 13 characterised in that the piezo-electric element (3) has a plurality of electrodes (3a) formed thereon; the motor having a base plate (4) provided with wiring members (41a) corresponding to the electrodes (3a); and an anisotropy conductor (4b) which connects together the electrodes (3a) and wiring members (41a).
Claim 16
Dependent Claim
38 words
An ultrasonic motor as claimed in claim 14 characterised in that the motor also comprises a circuit board (45) having a plurality of circuit members (46a) each of which is urged into contact with a respective electrode (3a).
Claim 17
Dependent Claim
29 words
An ultrasonic motor as claimed in any preceding claim characterised in that the stator (2) and/or the rotor (1) has a relieved portion (52) which is formed by etching.
Claim 18
Dependent Claim
67 words
An ultrasonic motor comprising a rotor (1); a stator (2) formed integrally with or provided with a vibrator (3) for oscillating the stator (2); the rotor (1) and/or the stator (2) having at least one portion (1a-1d) which in operation engages the other member so that the rotor (1) is driven by the stator (2) characterised in that the or each said portion comprises a projection (1a-1d).
Claim 19
Dependent Claim
67 words
An ultrasonic motor comprising a rotor (1); a stator (2) formed integrally with or provided with a vibrator (3) for oscillating the stator (2); the rotor (1) and/or the stator (2) having at least one portion (1a-1d) which in operation engages the other member so that the rotor (1) is driven by the stator (2) characterised in that the or each said portion comprises a projection (1a-1d).
Claim 20
Dependent Claim
59 words
An ultrasonic motor comprising a stator (2) oscillated by a vibrator (3), and a rotor (1) which is adapted to come in contact with said stator (2) and is driven by frictional force, said rotor (1) having a plurality of projections (1a-1) which are separated and formed on the rotor (1) and come in contact with said stator (2).
Claim 21
Dependent Claim
59 words
An ultrasonic motor comprising a stator (2) oscillated by a vibrator (3), and a rotor (1) which is adapted to come in contact with said stator (2) and is driven by frictional force, said rotor (1) having a plurality of projections (1a-1) which are separated and formed on the rotor (1) and come in contact with said stator (2).
References Cited (Backward Citations)
No citation records indexed.
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