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US3867933A Expired / Lapsed US ⏱️ 0.0 years remaining

Intrauterine device and process of making the same

Assignee: Tecna Corp
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Filing: 1973-03-06
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Granted: 1975-02-25
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Expires: 1993-03-06
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Abstract

Abstract An intrauterine device has a pair of initially flat, registering, triangle-shaped sheets of soft, rubber-like, substantially liquid-impervious, non-toxic flexible material of about the same dimensions as the undistorted human uterine cavity. The sheets are reinforced by a mat of flexible or pliable, non-stretchable fibers to prevent stretching of the sheets. The initially flat sheets are thermally preformed into a three-dimensional final shape and size and are then secured together in a marginal area forming a flat band all around the edges except for a gap at one apex. The sheets are also secured together along internal areas preferably bisecting the apices of the triangle except at said gap and except at a central location. This leaves unsecured or free zones in communication with each other and with said gap and extending approximately parallel to the sides of the triangle. In use, the unsecured zones are filled with fluid, such as liquid, introduced through the gap. This stiffens them so that, although they remain soft, they act somewhat like beams and are not readily distorted. The liquid can contain hormone crystals for slow release through a governing polymer coating.

Inventors

  • 👤 Sotiris Kitrilakis

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 21:49
CPC Classifications
A; A61; A61F; A61F6/00; A61F6/06; A61F6/14; A61F6/16

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 136 words
An intrauterine device comprising a pair of sheets of soft, rubber-like, substantially liquid-impervious, non-toxic material, said sheets having the approximate shape in plan of a triangle and being arranged in registry with each other, said sheets having about the same dimensions as the undistorted human uterine cavity, a non-stretchable mat of pliable fibers united with said sheets to prevent stretching thereof, means securing said sheets together in a planar band all around the edges of said sheets except for a gap at one apex thereof, and means securing said sheets together along areas bisecting the apices of said triangle except at said gap and except at a region at the center of said triangle leaving three unsecured zones communicating with each other and with said gap and extending approximately parallel to the sides of said triangle.
Claim 2
Dependent Claim 136 words
An intrauterine device comprising a pair of sheets of soft, rubber-like, substantially liquid-impervious, non-toxic material, said sheets having the approximate shape in plan of a triangle and being arranged in registry with each other, said sheets having about the same dimensions as the undistorted human uterine cavity, a non-stretchable mat of pliable fibers united with said sheets to prevent stretching thereof, means securing said sheets together in a planar band all around the edges of said sheets except for a gap at one apex thereof, and means securing said sheets together along areas bisecting the apices of said triangle except at said gap and except at a region at the center of said triangle leaving three unsecured zones communicating with each other and with said gap and extending approximately parallel to the sides of said triangle.
Claim 3
Dependent Claim 15 words
A device as in claim 1 in which said fibers of said mat are woven.
Claim 4
Dependent Claim 14 words
A device as in claim 1 in which said sheets are of silicone rubber.
Claim 5
Dependent Claim 13 words
A device as in claim 1 in which said fibers are of Dacron.
Claim 6
Dependent Claim 22 words
A device as in claim 1 including a tube joined to said sheets and communicating through said gap with said unsecured zones.
Claim 7
Dependent Claim 19 words
A device as in claim 1 in which said unsecured zones are preformed to a predetermined three dimensional configuration.
Claim 8
Dependent Claim 21 words
A device as in claim 1 including a fluid filling said unsecured zones and separating said sheets into said predetermined configuration.
Claim 9
Dependent Claim 21 words
A device as in claim 1 in which said zones are preformed to receive a predetermined maximum liquid volume when inflated.

References Cited (Backward Citations)

US3464409A Cited
US3452749A Cited
US3401689A Cited
US3779241A Cited
US3785376A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-02-24 1978-08-26 1979-02-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-02-24 1982-08-26 1983-02-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-02-24 1986-08-26 1987-02-25 $7700.00 Window Closed / Lapsed

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