Patent US4482318A successfully refreshed from Google Patents.
US4482318A
Expired / Lapsed
US
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Orthodontic spreader
Assignee: Bernhard Foerster GmbH
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Filing: 1983-03-14
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Granted: 1984-11-13
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Expires: 2003-03-14
Abstract
Abstract This invention relates to an orthodontic spreader, particularly for correcting the positions of molars in the upper jaw, and comprises pressure-transmitting nuts for applying force at points which are as close as possible to the center of resistance. The spreader is capable of applying a high pressure and has a large spreading capacity and is as convenient as possible for the patient. The actuating screw for moving the pressure-transmitting nuts in opposite directions comprises an actuating portion, which is disposed between said pressure-transmitting nuts. Guide rods are slidably mounted in both pressure-transmitting nuts and carry stops which axially restrain said guide rods.
Inventors
- 👤 Rolf Forster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:32
CPC Classifications
A; A61; A61C; A61C7/00; A61C7/10
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
122 words
In an orthodontic spreader comprising two pressure-transmitting nuts, an actuating screw including two screw-threaded, oppositely handed end portions screwed into respective ones of said pressure-transmitting nuts, and at least one guide rod, which is parallel to said screw and extends as a sliding fit through both said pressure-transmitting nuts, the improvement residing in that said actuating screw comprises an actuating portion between said screw-threaded end portions and restraining means for axially restraining said guide rod are provided and comprise stops carried by said guide rod, said actuating portion is laterally enlarged and said guide rod is provided with an annular groove, said actuating portion engaging with said groove to limit the axial movement of said guide rod relative to said actuating portion.
Claim 2
Dependent Claim
122 words
In an orthodontic spreader comprising two pressure-transmitting nuts, an actuating screw including two screw-threaded, oppositely handed end portions screwed into respective ones of said pressure-transmitting nuts, and at least one guide rod, which is parallel to said screw and extends as a sliding fit through both said pressure-transmitting nuts, the improvement residing in that said actuating screw comprises an actuating portion between said screw-threaded end portions and restraining means for axially restraining said guide rod are provided and comprise stops carried by said guide rod, said actuating portion is laterally enlarged and said guide rod is provided with an annular groove, said actuating portion engaging with said groove to limit the axial movement of said guide rod relative to said actuating portion.
Claim 3
Dependent Claim
19 words
The improvement set forth in claim 1 as applied to an orthodontic spreader comprising two of said guide rods.
Claim 4
Dependent Claim
30 words
The improvement set forth in claim 1, wherein said stops are engageable with said pressure-transmitting nuts to limit the axial movement of said guide rod relative to said pressure-transmitting nuts.
Claim 5
Dependent Claim
43 words
The improvement set forth in claim 3, wherein said stops consist of collars carried by said guide rod at opposite ends thereof, and each of said pressure-transmitting nuts has an axially outwardly facing surface which is engageable by one of said stop collars.
Claim 6
Dependent Claim
32 words
The improvement set forth in claim 4, wherein each of said pressure-transmitting nuts has an axially outer end face formed with a recess which is adapted to receive one of said stops.
Claim 7
Dependent Claim
40 words
The improvement set forth in claim 5, wherein each of said recesses is lined at its periphery with plastic material adapt to present a frictional resistance to the movement of the associated one of said stop collars in said recess.
Claim 8
Dependent Claim
23 words
The improvement set forth in claim 4, wherein each of said stop collars consists of an upset end portion of said guide rod.
Claim 9
Dependent Claim
80 words
The improvement as set forth in claim 4, as applied to a spreader comprising two pressure-applying members, each of which is molded around one of said pressure-transmitting nuts and engageable with the palate of a patient, wherein said restraining means permit an axial movement of said guide rod to a position in which one of said stop collars engages said axially outwardly facing surface of one of said nuts when said nuts are as close as possible to each other.
Claim 10
Dependent Claim
57 words
The improvement set forth in claim 1, wherein each of said pressure-transmitting nuts carries at its outer end a pressure-applying bracket having an intermediate portion which is secured to said pressure-transmitting nut and which extends transversely to the axial direction of said screw, and two arms extending from said bracket at right angles to said intermediate portion.
Claim 11
Dependent Claim
32 words
The improvement set forth in claim 9, wherein said spreader is designed to be received by the palate near the palatinal split and operable to apply pressure near the center of resistance.
Claim 12
Dependent Claim
40 words
The improvement set forth in claim 9, wherein each of said brackets constitutes a frame, one side of said frame constitutes said intermediate portion and the opposite side of said frame is engageable with the teeth to apply pressure thereto.
Claim 13
Dependent Claim
22 words
The improvement set forth in claim 9, wherein said arms are curved upwardly toward the palate to generally conform to the palate.
Claim 14
Dependent Claim
133 words
In an orthodontic spreader comprising two pressure-transmitting nuts, an actuating screw including two screw-threaded, oppositely handed end portions screwed into respective ones of said pressure-transmitting nuts, and at least one guide rod, which is parallel to said screw and extends as a sliding fit through both said pressure-transmitting nuts, the improvement residing in that said actuating screw comprises an actuating portion between said screw-threaded end portions, restraining means for axially restraining said guide rod are provided and comprise stops carried by said guide rod, said guide rod is formed on one side in a mid-portion with a flat and is formed in said mid-portion on the remainder of its periphery with a partial annular groove for receiving said actuating portion and said guide rod has ends rotatably mounted in both said pressure-transmitting nuts.
Claim 15
Dependent Claim
133 words
In an orthodontic spreader comprising two pressure-transmitting nuts, an actuating screw including two screw-threaded, oppositely handed end portions screwed into respective ones of said pressure-transmitting nuts, and at least one guide rod, which is parallel to said screw and extends as a sliding fit through both said pressure-transmitting nuts, the improvement residing in that said actuating screw comprises an actuating portion between said screw-threaded end portions, restraining means for axially restraining said guide rod are provided and comprise stops carried by said guide rod, said guide rod is formed on one side in a mid-portion with a flat and is formed in said mid-portion on the remainder of its periphery with a partial annular groove for receiving said actuating portion and said guide rod has ends rotatably mounted in both said pressure-transmitting nuts.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-11-13 | 1988-05-14 | 1988-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-13 | 1992-05-14 | 1992-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-13 | 1996-05-14 | 1996-11-13 | $7700.00 | Window Closed / Lapsed |