FR2690018A1 - Piezoelectric modular motor with stator having two active faces - has both faces excited by transducers having two active faces insulated by coaxial element - Google Patents

Piezoelectric modular motor with stator having two active faces - has both faces excited by transducers having two active faces insulated by coaxial element Download PDF

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Publication number
FR2690018A1
FR2690018A1 FR9112485A FR9112485A FR2690018A1 FR 2690018 A1 FR2690018 A1 FR 2690018A1 FR 9112485 A FR9112485 A FR 9112485A FR 9112485 A FR9112485 A FR 9112485A FR 2690018 A1 FR2690018 A1 FR 2690018A1
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France
Prior art keywords
stator
motor
characterized
rotor
gt
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Withdrawn
Application number
FR9112485A
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French (fr)
Inventor
Minotti Patrice
Froelicher Michel
Gonnard Paul
Eyraud Lucien
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
CENTRE TECH IND HORLOGERE
CETEHOR
LABORATOIRE MECANIQUE APPLIQUEE
LGEF
MECANIQUE APPLIQUEE LAB
Original Assignee
CENTRE TECH IND HORLOGERE
CETEHOR
LABORATOIRE MECANIQUE APPLIQUEE
LGEF
MECANIQUE APPLIQUEE LAB
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Priority to FR9112485A priority Critical patent/FR2690018A1/en
Publication of FR2690018A1 publication Critical patent/FR2690018A1/en
Application status is Withdrawn legal-status Critical

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Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02NELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
    • H02N2/00Electric machines in general using piezo-electric effect, electrostriction or magnetostriction
    • H02N2/10Electric machines in general using piezo-electric effect, electrostriction or magnetostriction producing rotary motion, e.g. rotary motors
    • H02N2/16Electric machines in general using piezo-electric effect, electrostriction or magnetostriction producing rotary motion, e.g. rotary motors using travelling waves, i.e. Rayleigh surface waves
    • H02N2/163Motors with ring stator

Abstract

The present invention relates to a piezoelectric motor constituted by a stator part (1) having two annular parts (4, 5) excited by piezoelectric transducers with two active faces respectively (7, 6) insulated by a piece of coaxial insulation. (9). The rotor part (2) has two annular parts (14, 16) arranged symmetrically with respect to a median plane (3). The invention also relates to an assembly of motor elements in series. </ P>

Description

MODULAR PIEZOELECTRIC MOTOR COMPRISING A
STATOR HAS TWO ACTIVE FACES.

 The present invention relates to a piezoelectric motor. The piezoelectric motor operates according to the principle of the inverse piezoelectric conversion, that is to say the transformation of an electrical voltage into a mechanical deformation.

Piezoelectric motors known in the prior art are usually composed
a stator formed of a flexible part excited by a piezoelectric transducer
- A rotor coated with antifriction material that allows to convert with good efficiency the vibrations of the stator in motion of the rotor - a system that allows to apply a permanent and regular axial pressure between the stator and the rotor.

 When sinusoidal voltages of suitable amplitude and frequency are applied to the piezoelectric ceramic and a suitable relative phase shift, progressive vibrations of bending vibration are produced on the flexible part. A material point on the surface of the stator will describe an elliptical trajectory. The frequency of the AC voltage applied to the piezoelectric transducer is determined so as to correspond substantially to the mechanical resonance frequency of the assembly constituted by the stator and the associated piezoelectric transducers.

 Such engines have been the subject of several prior patents, and in particular a description of the general principle will be found in the journal IBM Technical Disclosure Bulletin No. 16 of 1973, article of Mr. BARTH, or in the US patent issued under the number 4,736,129, or in USR 60,400 of the KK Shinsei Kogio Company.

 These engines have high torque at low speeds. In addition, they have the advantage of being self-locking, that is to say to have a very large holding torque.

 It has also been proposed in the prior art to use both sides of the stator. The patent WO91 / 11850 describes an ultrasonic motor which comprises a stator excited by one or more ultrasonic oscillators and a first movable part in contact with one of the faces of the stator. A second moving part is in pressure contact with a second surface face of the stator. This embodiment does not, however, optimize the efficiency of the motor because one of the faces of the piezoelectric oscillators vibrates in a vacuum. A first object of the invention is to overcome this disadvantage by providing a "sandwich" structure to improve the coupling and optimize the efficiency of ultrasonic oscillators implemented.

 However, for some applications, the torque that can be achieved with a motor of fixed dimensions may be insufficient.

 To overcome this disadvantage, it has been proposed to increase the amplitude of the voltage applied to the piezoelectric transducer. However, this requires the use of a high voltage source incompatible with certain applications.

 It has been proposed in the prior art to multiply the number of piezoelectric motors by coupling them in parallel. In particular, French Patent No. 2,618,184 proposes an ultrasonic motor comprising several stators and several coaxially assembled rotors, and an output shaft driven by all the rotors.

 This solution, relatively simplistic, translates into a certain mechanical complexity, insofar as the axis serves both to drive an external member and the positioning of the stators. It is therefore necessary to ensure its guidance and positioning with high precision bearings capable of absorbing high torques. In addition, slight differences in the characteristics of the associated motors result in a significant loss of efficiency. Finally, the size and weight of such engines are the disadvantages for micro-mechanical applications, particularly in the field of medical instrumentation.

 The engine according to the present invention aims to overcome this disadvantage. For this purpose, it relates to a motor with piezoelectric transducers comprising a stator symmetrical with respect to a median plane and having two active faces driving two coupled rotor parts disposed on either side of the stator part, the piezoelectric transducer being included in the stator so as to excite it to excite on both vibratory faces of said transducer.

 Such an engine will be described hereinafter in a rotary embodiment. It is obvious that other configurations can be envisaged without departing from the scope of the invention. In particular, such an engine can be made in a linear configuration, or in a cylindrical configuration in which the rotors and the stator are of cylindrical shape.

 This engine has the advantage of great symmetry and optimization of the piezoelectric effects that produce. In addition, it is possible to manufacture a modular motor constituted by assembling a set of self-centering modular elements.

 According to an advantageous embodiment, the stator consists of two annular parts arranged on either side of a coaxial central electrical insulation piece having mechanical characteristics substantially identical to the mechanical characteristics of the annular parts, at least one piezoelectric transducer. being interposed between said insulating piece and each of the annular stator pieces, the motor being further characterized in that it comprises two rotors each bearing on one of the outer surfaces of the stator. This symmetrical support makes it possible to integrate the support functions in the rotor assembly, unlike the known type of engines where the support function is exerted by the output shaft cooperating with the motor housing, whereas in the motors of known type, the bearing function of the rotor on the stator is a function of the accuracy of the manufacture of the housing and the output shaft and their assembly, in the motors according to the invention, this function maintains its performance independently of its assembly in a case.

 According to an advantageous embodiment, the piezoelectric transducer is constituted by a plurality of pellets cut from a film of piezoelectric material. By "pellets" are meant separate elements of cylindrical shape, that is to say whose shape corresponds to a volume generated by the movement of a generator along a closed path. Preferably, the pellets are disk-shaped in order to facilitate their positioning between the two annular portions of the stator.

 According to another advantageous embodiment, the rotor comprises two coaxial annular parts each resting on one of the faces of the stator, said coaxial annular parts being joined by elastic means exerting permanent prestressing.

 Advantageously, the annular rotor parts cooperate with a central hub by means of elastically deformable flanges.

The present invention will be better understood on reading the following description, referring to the drawings where
- Figure 1 shows a sectional view of an engine according to the invention
FIG. 2 represents a sectional view of a multi-stage engine
FIG. 3 represents a view in median section of the arrangement of the piezoelectric transducers according to a first variant
FIG. 4 represents a view in median section of the arrangement of the piezoelectric transducers according to a second variant.

FIG. 1 represents a sectional view of a piezoelectric motor according to the invention. The motor comprises a stator part (1) and a rotor part (2) symmetrical with respect to a median plane (3)
The stator part (1) consists of two annular parts (4, 5) made of metal, for example made of bronze. These two stator parts (4, 5) are arranged on either side of a central annular insulation piece (6). This insulating piece (6) is constituted by an electrically insulating washer, having mechanical characteristics, and in particular a Young's constant corresponding substantially to the mechanical characteristics, and in particular to the Young's constant, of the metallic material constituting the stator parts (4). , 5). It is advantageously made of a composite material.

Two piezoelectric transducers respectively (7, 8) are arranged on either side of the insulating piece (6), between the surface of said insulating piece (6) and the lower surface of the stator parts (4, 5). ). The electrical voltage is applied between the stator parts (4, 5) constituting the ground and excitation electrodes (9, 10)
The piezoelectric transducers (9, 10) are made, depending on the size of the motor, in the form of a ceramic film of a thickness calibrated according to the dimensions of the motor or in the form of rings or ceramic pellets. An embodiment will be described in more detail below.

 The rotor (2) is constituted by a central hub (12) of cylindrical shape and by two rotor parts respectively formed by a disc portion (13) extending by an annular bearing portion (14) for the first rotor part, and by a disc portion (15) extending by an annular bearing portion (16) for the second rotor part. The rotor parts are made of an elastically deformable metal. The hub (12) has two grooves (17, 17 ') for positioning and assembling the stator parts via their disc portion (13, 15). The grooves (17, 17 ') have a lateral flat for the angular positioning of the two disc parts (13, 15).

 The spacing e of the grooves (17, 17 ') of the means (12) is determined so that the distance between the friction surfaces (19, 20) of the annular contact portions (14, 16) provided with their material anti-friction (21, 22) are smaller than the thickness of the stator part. Therefore, after assembly of the two parts of the rotor (2) and after crimping the end of the hub (12), the two faces in contact exert on the stator part (1) a permanent pressure. This pressure is exerted independently of any assembly of the rotors and the stator in a housing or on an axis.

 The device thus produced can therefore be easily associated with a coupling axis, without it being necessary to provide means for guiding and positioning said axis.

 To improve the relative positioning of the stator parts and the rotor parts, an intermediate hub (25) which can be arranged coaxially with the rotors and the stator is provided.

 The assembly in the housing is effected by means of the insulation part extending beyond the stator parts (1).

 The radial extension (23) preferably has a flat portion providing angular positioning relative to the housing (24). The connection between the housing (24) and the insulation piece is carried out by any known means, for example by screwing, riveting, or simply by wedging into a cavity having the required dimensions.

 The characteristics of all the modular elements make it possible to consider them as modules that can be combined to form a complete range of modular motors. Such a solution is shown in FIG. 2. The motors presented in FIG. 2 are constituted by four modular element systems (30, 31, 32, 33), each of which corresponds to the device described in FIG.

 The outer housing is constituted by two end pieces (34, 35), and four intermediate parts (36 to 39) having a central cavity (40) for positioning the radial extension (23) of the insulation material of each engines. The axial locking is effected via the lower end of the annular edge (41) of the next intermediate part. A perfectly modular motorized device is thus produced, making it possible, from a reduced number of standard elements, to modify and adapt the engine performance to the need of the particular application.

 The assembly of the multi-stage motor is carried out by known means, for example by a screw passing through all the intermediate parts (36 to 39), or by clipping. In the latter case, each of the intermediate parts has at its upper end a groove (42) cooperating with a complementary rib (43) adapted to snap into said groove by elastic deformation of the annular flange (41) when an axial pressure is exercised between two consecutive intermediate parts. These intermediate pieces (36 to 39) therefore have an annular shape with two superimposed steps of different sections. The shoulder (40) resulting from the change of section allows the maintenance of the radial extension (23) of the insulation material (9).

 Advantageously, the shape of the stage of larger section is not cylindrical, but has a clean flat to prevent rotation of the motor which is inserted in the intermediate part considered. The axial locking is achieved by the annular rim (41) of the next intermediate piece.

 The single drive shaft (44) is coupled to the central hubs of each of the rotors of the drive members (30 to 33). It has a boss (45) corresponding to a flat part (46) complementary provided on said hubs of the rotors, and adapted to ensure the drive of the rotors. The axial positioning is carried out by any known means, for example by rings limiting the axial race, or by lateral grooves corresponding to complementary ribs provided on the inner surface of the hubs and ensuring axial positioning by clipping.

The number of motor elements that can thus be coupled is not limited, and allows for a complete range of graduated power motors, from identical motor elements manufactured industrially in large series.

 FIG. 3 represents a first mode of arrangement of the piezoelectric transducers made in the form of pellets of cylindrical shape. The pellets are glued to have alternate polarities.

According to this arrangement mode, the number P of pellets corresponds to:
P = 2 (n - 1)
where n denotes the rank of the vibration mode.

The table below indicates, in degrees, the angular position Pi of the pellets from a reference axis, according to the rank n of the vibration mode selected.

Figure img00090001

<Tb>

n <SEP> 3 <SEP> 4 <SEP> 5 <SEP> 6 <SEP> 7 <SEP> 8 <SEP> 9 <SEP> 10 <SEP>
<tb> P1 <SEP> 75 <SEP> 56.25 <SEP> 45 <SEP> 37.5 <SEP> 32.2 <SEP> 28.15 <SEP> 25 <SEP> 22.5 <SEP>
<tb> P2 <SEP> 135 <SEP> 101.25 <SEP> 81 <SEP>. <SEP> 67.5 <SEP> 57.9 <SEP> 50.65 <SEP> 45 <SEP> 40.5
<tb> P3 <SEP> 146 <SEP> 25 <SEP> 117 <SEP> 97.5 <SEP> 83.6 <SEP> 73.15 <SEP> 65 <SEP> 58.5
<tb> P4 <SEP> 153 <SEP> 127.5 <SEP> 109.3 <SEP> 95 <SEP> 65 <SEP> 85 <SEP> 76.5
<tb> P <SEP> 157 <SEP> 5 <SEP> 135 <SEP> 0 <SEP> 118.15 <SEP> 105 <SEP> 94.5
<tb> P6 <SEP> 160 <SEP> 7 <SEP> 140 <SEP> 65 <SEP> 125 <SEP> 112.5
<tb> P7 <SEP> 163 <SEP> 15 <SEP> 145 <SEP> 130.5
<tb> P8 <SEP> ==== <SEP><SEP> 165 <SEP> 148.5
<tb> P9 <SEP> 166.5
<Tb>
The angular difference between two consecutive pellets and therefore of opposite polarity corresponds to half a wavelength. By wavelength is meant the period of stationary mechanical deformation waves generated in the structure constituted by the stator, the piezoelectric pellets (64 to 79) and the adhesive joint.

 The pellets are divided into two series, respectively (64 to 71) and (72 to 79). Between these two series of pellets is a first dead zone (80) with an angular aperture corresponding to three quarters of a wavelength, and a second dead zone (81) with an angular aperture of a quarter of a wavelength. 'wave. By dead zone is meant an area of the rotor surface on which no piezoelectric pellet can be applied.

 The first series of pads (64 to 71) is excited by a conductive electrode (82) for applying to each of the pads (64 to 71) an electric field. The rotor constitutes the mass, and therefore the other electrode.

 A sinusoidal voltage UsinO) type is applied to this electrode (82).

 The second series of piezoelectric pellets (62 to 79) is excited by a second metal electrode (83) powered by a voltage Ucosot, and phase shifted by a quarter of a wavelength. The sinusoidal voltages applied to each of the electrodes (82, 83) cause the bending vibrations of each of the electrodes (64 to 79) under phase conditions suitable for exciting the rotor by resonance and for generating two stationary waves, the resultant of which results in to a progressive wave resulting in the surface movements suitable for driving the rotor.

 Figure 4 illustrates a second mode of arrangement of the piezoelectric pellets.

 In this second mode of arrangement, the pellets are arranged so as to present alternately two polarized elements in a first direction, then two polarized elements in an opposite direction.

According to this second disposition mode, the number P of pellets corresponds to:
P = 4n
where n denotes the rank of the vibration mode.

 Unlike the positioning mode described in FIG. 3, where each of the series of electrodes is excited by an electrode (82, 83) substantially covering a semicircle, the piezoelectric pellets, in this second embodiment, are individually excited. Each of the pads supports on its surface opposite to that of the rotor a conductive pad fed by a sinusoidal voltage.

The distribution of the pellets on the surface of the rotor corresponds to a succession of patterns where:
the first patch of the pattern is polarized in a first direction and is powered by a UsincOt type voltage
the second pellet of the pattern is polarized in the same first direction and is powered by a Ucosa voltage) t
the third pellet of the pattern is polarized in a second direction opposite to the first direction and is powered by a UsinO voltage) t
the fourth pellet of the pattern is polarized in the second direction and is powered by a voltage of UcosOt type.

 This motive is repeated n times; n denoting the rank of the vibration mode. Two consecutive pellets are angularly apart by a quarter of a wavelength.

 As before, two stationary vibration waves are produced, the superposition of which generates a progressive wave causing the surface movements driving the rotor. This second method of positioning the pellets has the advantage of greater symmetry, which reduces parasitic harmonics.

 These pellets are advantageously cut in a bar of ceramic material or in a piezoelectric film, such piezoelectric films are in particular polyvinylidene fluoride films.

Their thickness is between ten microns and one millimeter.

 The invention is described in the foregoing by way of non-limiting example, it is understood that the skilled person will be able to achieve many variants, without departing from the scope of the invention.

Claims (12)

 1 - Motor with piezoelectric transducers constituted by at least one stator made of a deformable material elastically excited by a piezoelectric transducer, and by at least one rotor coated with an antifriction material for converting the surface movements of the stator in motion rotor drive, the motor further comprising means for exerting constant and constant pressure between the rotor and the stator, characterized in that the stator is symmetrical with respect to a median plane (3) and has two active faces leading to two coupled rotor parts disposed on either side of the stator part (1), the piezoelectric transducers being included in the stator so as to excite it along the two vibratory faces.
 2 - motor with piezoelectric transducers according to claim 1, characterized in that the stator part (1) consists of two annular parts (4, 5) arranged on either side of a central insulation part (9) coaxial, piezoelectric transducers (7, 8) with two active faces being interposed between said electrical insulation part (9) and each of the annular parts (4, 5) of the rotor and in that the motor comprises a rotor part (2 ) resting on each of the outer surfaces of the stator part (1).
 3 - motor with piezoelectric transducers according to any one of the preceding claims, characterized in that the piezoelectric transducer is constituted by a plurality of cylindrical pellets cut from a film of piezoelectric material.
 4 - motor with piezoelectric transducers according to any one of the preceding claims, characterized in that the rotor part (2) is constituted by two coaxial annular parts (14, 16), each bearing on one of the outer faces of the stator part (1), said annular parts (14, 16) being joined by resilient means providing prestressing.
 5 - motor with piezoelectric transducers according to claim 4, characterized in that the annular rotor parts (14, 16) cooperate with a central hub (12) via disc-shaped flanges (13, 15) elastically deformable.
 6 - motor with piezoelectric transducers according to claim 5, characterized in that the rotor part (2) is constituted by a first portion constituted by a hub (11) having at one of these ends a disc portion (13) extending by an annular portion (14), the hub (11) having at the opposite end a groove (17) for positioning a complementary portion formed by a disc portion (14) extended by an annular portion (16), the axial length e of the hub (12) being fixed so that the bearing surfaces of the anti-friction materials (21, 22) are spaced, at rest, by a distance less than the thickness of the stator part ( 1).
 7 - motor with piezoelectric transducers according to any one of the preceding claims, characterized in that the insulating material (9) has a radial extension (23).
 8 - Motor assembly according to any one of the preceding claims, characterized in that it consists of a plurality of intermediate pieces (36 to 39) each having a means for retaining the stator part (1) of the motors ( 30 to 33).
 9 - Motorized assembly according to the preceding claim, characterized in that said intermediate pieces (36 to 39) are constituted by a ring having a cavity (40) of complementary shape to the shape of the radial extension (23) of the insulation material ( 9).
 10 - Motorized assembly according to the preceding claim, characterized in that the intermediate parts (36 to 39) have an annular flange (41) whose outer diameter corresponds to the shoulder (40) of the consecutive intermediate piece, the thickness of said annular flange (41) being determined so that the radial extension (23) of each of the stators of the driving elements (30 to 33) is locked between the shoulder (40) of an intermediate piece and the lower end of the annular flange (41) of the next intermediate piece.
 11 - Motorized assembly according to any one of claims 8 to 10, characterized in that the annular flange (41) has a rib (43) adapted to cooperate with a groove (42) provided on the wall of the next intermediate piece.
 12 - Motorized assembly according to any one of claims 8 to 10 characterized in that the rotors of the motor elements (30 to 33) are driven by a single axis (44).
FR9112485A 1991-10-10 1991-10-10 Piezoelectric modular motor with stator having two active faces - has both faces excited by transducers having two active faces insulated by coaxial element Withdrawn FR2690018A1 (en)

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2715780A1 (en) * 1994-02-01 1995-08-04 Imra Europe Sa Stator of a piezoelectric rotary motor and a piezoelectric rotary motor comprising such a stator.
WO1996013870A1 (en) * 1994-10-28 1996-05-09 Robert Bosch Gmbh Travelling wave motor
EP0793282A1 (en) * 1996-02-29 1997-09-03 Figest B.V. Piezoelectric travelling wave motor
US7806119B2 (en) 2003-08-14 2010-10-05 Intersurgical Uab Airway device
US8215307B2 (en) 2002-08-14 2012-07-10 Intersurgical Uab Airway device
USD665254S1 (en) 2011-06-08 2012-08-14 Intersurgical Ag Airway device packaging
USD688787S1 (en) 2011-06-08 2013-08-27 Intersurgical Ag Airway device cap and strap holder
USD712244S1 (en) 2011-09-23 2014-09-02 Intersurgical Ag Medical device package
US9265905B2 (en) 2010-06-24 2016-02-23 Ashkal Developments Limited Stopper device
USD761952S1 (en) 2012-07-27 2016-07-19 Docsinnovent Limited Airway device
US9937311B2 (en) 2012-01-27 2018-04-10 Ashkal Developments Limited Stopper device
USD842456S1 (en) 2015-12-15 2019-03-05 Intersurgical Ag Airway device

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JPS6389074A (en) * 1986-09-30 1988-04-20 Fukoku:Kk Surface-wave motor
FR2618184A1 (en) * 1987-07-16 1989-01-20 Somfy Ultrasound engine and elementary engine for producing such an engine
JPH01243860A (en) * 1988-03-22 1989-09-28 Matsushita Electric Ind Co Ltd Ultrasonic motor
WO1991011850A1 (en) * 1990-01-26 1991-08-08 Licentia Patent-Verwaltungs-Gmbh Ultrasonic motor with two rotors

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Publication number Priority date Publication date Assignee Title
JPS6389074A (en) * 1986-09-30 1988-04-20 Fukoku:Kk Surface-wave motor
FR2618184A1 (en) * 1987-07-16 1989-01-20 Somfy Ultrasound engine and elementary engine for producing such an engine
JPH01243860A (en) * 1988-03-22 1989-09-28 Matsushita Electric Ind Co Ltd Ultrasonic motor
WO1991011850A1 (en) * 1990-01-26 1991-08-08 Licentia Patent-Verwaltungs-Gmbh Ultrasonic motor with two rotors

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Title
PATENT ABSTRACTS OF JAPAN vol. 12, no. 324 (E-653)2 Septembre 1988 & JP-A-63 089 074 ( FUKOKU:KK ) 20 Avril 1988 *
PATENT ABSTRACTS OF JAPAN vol. 13, no. 581 (E-865)21 Décembre 1989 & JP-A-1 243 860 ( MATSUSHITA ELECTRIC IND CO LTD ) 28 Septembre 1989 *

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2715780A1 (en) * 1994-02-01 1995-08-04 Imra Europe Sa Stator of a piezoelectric rotary motor and a piezoelectric rotary motor comprising such a stator.
EP0669662A1 (en) * 1994-02-01 1995-08-30 Imra Europe S.A. Piezoelectric rotating motor
US5554905A (en) * 1994-02-01 1996-09-10 Imra Europe Sa Piezoelectric rotating motor
WO1996013870A1 (en) * 1994-10-28 1996-05-09 Robert Bosch Gmbh Travelling wave motor
EP0793282A1 (en) * 1996-02-29 1997-09-03 Figest B.V. Piezoelectric travelling wave motor
FR2745664A1 (en) * 1996-02-29 1997-09-05 Figest Bv piezoelectric motor wave
US5828158A (en) * 1996-02-29 1998-10-27 Figest Bv Traveling wave piezoelectric motor
US9475223B2 (en) 2002-08-14 2016-10-25 Muhammed Aslam Nasir Method of manufacturing an airway device
US8215307B2 (en) 2002-08-14 2012-07-10 Intersurgical Uab Airway device
US10040231B2 (en) 2002-08-14 2018-08-07 Muhammed Aslam Nasir Airway device
US8778248B2 (en) 2002-08-14 2014-07-15 Muhammed Aslam Nasir Method of manufacturing an airway device
US9266268B2 (en) 2002-08-14 2016-02-23 Muhammed Aslam Nasir Method of manufacturing an airway device
US8485188B2 (en) 2003-08-14 2013-07-16 Muhammed Aslam Nasir Airway device
US7806119B2 (en) 2003-08-14 2010-10-05 Intersurgical Uab Airway device
US9265905B2 (en) 2010-06-24 2016-02-23 Ashkal Developments Limited Stopper device
USD665254S1 (en) 2011-06-08 2012-08-14 Intersurgical Ag Airway device packaging
USD688787S1 (en) 2011-06-08 2013-08-27 Intersurgical Ag Airway device cap and strap holder
USD712244S1 (en) 2011-09-23 2014-09-02 Intersurgical Ag Medical device package
USD768846S1 (en) 2012-01-27 2016-10-11 Ashkal Developments Limited Airway device
USD769442S1 (en) 2012-01-27 2016-10-18 Ashkal Developments Limited Airway device
US9937311B2 (en) 2012-01-27 2018-04-10 Ashkal Developments Limited Stopper device
USD761952S1 (en) 2012-07-27 2016-07-19 Docsinnovent Limited Airway device
USD842456S1 (en) 2015-12-15 2019-03-05 Intersurgical Ag Airway device

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