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US3845332A Expired / Lapsed US ⏱️ 0.0 years remaining

Ultrasonic motor

Assignee: Ortech Corp
•
Filing: 1972-03-14
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Granted: 1974-10-29
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Expires: 1992-03-14
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Abstract

Abstract This invention provides an ultrasonic motor in which a central transducer means is sandwiched between front and rear stubs. The front stub is made of either magnesium or magnesium alloy, and there is provided a cylindrical housing having means for clamping the stubs axially together. The clamping locations on the stubs are adjacent the transducer and the configuration of the connection between the housing and the front stub includes a frusto-conical bearing face, the latter being necessary due to the weakness of the material from which the front stub is constructed. It is highly desirable that the front stub be made of magnesium or magnesium alloy, however, because of the suitability of such material for impedance matching into water or liquid.

Inventors

  • 👤 A Last

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 18:56
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0607; B06B1/0611; B06B1/0618; H; H04; H04R; H04R17/00; H04R17/04; H04R17/08

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 151 words
An ultrasonic motor comprising: transducer means, a rear stub in surface contact with said transducer means, a front stub in surface contact with said transducer means, and being made of a material chosen from the group consisting of magnesium and magnesium alloy, means for exciting the transducer means such that the ultrasonic motor vibrates in its fundamental mode, a substantially cylindrical housing having means for clamping said front and rear stubs axially together, the clamping locations on said stubs being immediately adjacent the transducer means and spaced from an anti-node so that a major portion of each stub extends axially beyond its clamping location in the direction away from the transducer means, the front stub having an outwardly and rearwardly flaring flange with a substantially frusto-conical bearing face, the cylindrical housing having a frusto-conical bearing surface complementary to said bearing face adapted to grip the front stub through said bearing face.
Claim 2
Dependent Claim 151 words
An ultrasonic motor comprising: transducer means, a rear stub in surface contact with said transducer means, a front stub in surface contact with said transducer means, and being made of a material chosen from the group consisting of magnesium and magnesium alloy, means for exciting the transducer means such that the ultrasonic motor vibrates in its fundamental mode, a substantially cylindrical housing having means for clamping said front and rear stubs axially together, the clamping locations on said stubs being immediately adjacent the transducer means and spaced from an anti-node so that a major portion of each stub extends axially beyond its clamping location in the direction away from the transducer means, the front stub having an outwardly and rearwardly flaring flange with a substantially frusto-conical bearing face, the cylindrical housing having a frusto-conical bearing surface complementary to said bearing face adapted to grip the front stub through said bearing face.
Claim 3
Dependent Claim 42 words
The invention claimed in claim 1, in which the frusto-conical bearing face defines an angle of substantially 45* with the axis of the front stub. 3. The invention claimed in claim 1, in which the front and rear stubs are substantially cylindrical.
Claim 4
Dependent Claim 20 words
The invention claimed in claim 1, in which the distance between said clamping locations is not greater than one-fourth wavelength.
Claim 5
Dependent Claim 93 words
The invention claimed in claim 1, which further includes a cooling element, the transducer means including a first and a second transducer element sandwiching the cooling element between them, the first transducer element having a central opening, the rear stub having a passage in registry with said central opening, and the cooling element having passageway means for communicating said central opening in the first transducer element with the space surrounding the cooling element, whereby a fluid cooling medium passing through said passageway means may absorb heat by conduction from the said transducer elements.
Claim 6
Dependent Claim 75 words
An ultrasonic motor as claimed in claim 5, in which the cooling element includes a flat cooling member having mutually convergent slots extending from the periphery to locations short of a hypothetical point of convergence, and two plate-like shims, one on either side of the flat cooling member and each contacting a stub, the shim contacting the rear stub having a central aperture of sufficient size to leave uncovered the inner extremities of the slots.
Claim 7
Dependent Claim 52 words
The invention claimed in claim 6, in which said cylindrical housing encloses and in part defines an annular chamber outwardly adjacent said cooling disc, said slots being in communication with the annular chamber, the cylindrical housing having aperture means by which the annular chamber communicates with the exterior of the cylindrical housing.
Claim 8
Dependent Claim 151 words
An ultrasonic motor as claimed in claim 7, in which the transducer elements are piezoelectric crystals of a material chosen from the group consisting of: barium titanate, and lead zirconate titanate or like high power material; and in which for each transducer element the cooling disc and the shims constitute one electrode, while the respective stub constitutes the other electrode, the two stubs being in electrical communication through the cylindrical housing, the latter being of an electrically conductive material, the rear stub having an open-ended passage of which one end is in registry with said central aperture, the ultrasonic motor further comprising a terminal assembly fixed to the rear stub at the other end of said openended passage and including a double terminal, an insulated wire constituting one lead from the terminal and extending along said open-ended passage to connect to one shim, the terminal being grounded to the rear stub.
Claim 9
Dependent Claim 46 words
An ultrasonic motor as claimed in claim 8, further including means defining an air-line connection communicating with said passage, whereby an air forced under pressure into said air-line connection passes through said passage and said slots into said annular chamber, emerging therefrom through said aperture means.
Claim 10
Dependent Claim 66 words
An ultrasonic motor as claimed in claim 8, in which the terminal assembly includes a vent opening through which said passage is open to the surround, whereby use of the ultrasonic motor in an attitude in which the vent opening is elevated above the aperture means causes air to circulate by convection from the annular chamber through the slots and the passage to said vent opening.

References Cited (Backward Citations)

US3101419A Cited
US3140859A Cited
US3230403A Cited
US3370186A Cited
US3283182A Cited
US3368085A Cited
US3578996A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-10-28 1978-04-29 1978-10-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-10-28 1982-04-29 1982-10-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-10-28 1986-04-29 1986-10-29 $7700.00 Window Closed / Lapsed

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