Gasket, in particular for a pressurised liquid

Patent metadata

Field	Value
Publication number	US-9388904-B2
Application number	US-201314428185-A
Country	US
Kind code	B2
Filing date	Sep 16, 2013
Priority date	Sep 14, 2012
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

A gasket, in particular for a pressurized liquid, includes: a support ring ( 2 ) having an axial flange ( 3 ) and a radial flange ( 4 ); and a PTFE washer ( 5 ) arranged on the ring ( 2 ), the washer at least partially covering the outer face ( 3′ ) of the axial flange ( 3 ) and forming a flexible inner sealing lip ( 6 ) intended to be applied against an element to be sealed, such as a shaft. The sealing lip ( 6 ) includes an annular portion bearing mostly on the element to be sealed and a curved annular connecting portion. The sealing lip ( 6 ) has a small thickness (EL), typically less than 0.8 mm, and, in the absence of stress, substantially forms a frustoconical ring or sleeve having a vertex angle of between 40° and 80°.

First claim

The invention claimed is:

1. A sealing joint for pressurized liquid, the sealing joint comprising:
a support ring or frame with an external axial flange and an internal radial flange; and
a washer made of a Teflon-based sealing material, which is mounted or arranged on said ring, by at least partially covering the external surface of the axial flange and by extending beyond the inner end of the radial flange to form a flexible sealing lip, configured to be applied circumferentially against or on an element that is to be sealed, the element to be sealed being a rotational cylindrical element, the sealing lip having an annular portion that at least partially rests on the element that is to be sealed and an annular curved connecting portion, the sealing lip having a thickness of less than 0.8 mm, and forming, in the absence of stress, essentially a sleeve or tapered ring with a peak angle of 90°−α, with α being between 10° and 50°.

2. The sealing joint according to claim 1 , wherein the sealing lip, in the form of a tapered sleeve with an essentially flat wall in the absence of stress, is connected to the part of the washer that rests on and/or is made integral with the radial flange, by a precurved or inflected annular region of the washer, located immediately after the inner end of said radial flange, oriented in the direction of the medium that is to be sealed and that is part of the annular connecting portion.

3. The sealing joint according to claim 2 , wherein the thickness of the sealing lip is between 0.4 and 0.7 mm, and
wherein the angle α is between 15° and 45°, the precurved region being shaped by local deformation of the wall of the washer, before or after mounting on the support ring.

4. The sealing joint according to claim 1 , wherein the thickness of the sealing lip is between 0.4 and 0.7 mm, and
wherein the angle α is between 15° and 45°, the precurved region being shaped by local deformation of the wall of the washer, before or after mounting on the support ring.

5. The sealing joint according to claim 4 , wherein the thickness of the sealing lip is between 0.45 and 0.65 mm, and
the angle α is between 20° and 40°.

6. The sealing joint according to claim 1 , wherein the relative dimensions and arrangements of the support ring, the washer made of a Teflon-based material, and the element that is to be sealed define an area for tight contact and support of the portion of the sealing lip on said element with an axial distance of between 1.5 and 5.0 mm from the free edge of said lip.

7. The sealing joint according to claim 1 , wherein the sealing lip comprises, at the level of the contact surface of the portion of the lip configured to come to rest on the element that is to be sealed, a delivery structure that is helical or in the form of threading, in the form of a groove with opposite sides of inclinations or different slopes, with a cross-section or profile that is asymmetrically triangular in shape.

8. The sealing joint according to claim 6 , wherein the axial distance is between 2.5 and 3.5 mm from the free edge of said lip.

9. The sealing joint according to claim 1 , wherein the sealing washer extends beyond the free edge of the axial flange and forms a projecting part, inclined or curved toward the interior and covering at least the outside ridge of said free edge.

10. The sealing joint according to claim 1 , further comprising an annular structure for support and reinforcement for the sealing lip that is located on the side opposite to the medium that is to be sealed and extending at the level of the curved annular portion of said lip, by partially assuming the shape of the annular portion and by being separated from the annular portion.

11. The sealing joint according to claim 10 , wherein the annular structure for support and reinforcement includes a curved circumferential flange, the curving radius of said flange being greater than the curving radius, in the absence of pressure, of the annular connecting portion of the sealing lips after installation of the sealing joint around the element that is to be sealed, the curving radius of the flange being greater than the curving radius of the precurved annular region of the washer, in the absence of stress on the sealing lip.

12. The sealing joint according to claim 11 , wherein the annular structure for support and reinforcement, in the form of a circumferential flange, extends up to a short distance from the element that is to be sealed, the free edge of the flange being located at a distance from said element that is less than the thickness of the sealing lip.

13. The sealing joint according to claim 11 , wherein the structure for support and reinforcement is part of a second ring that comprises at least one radial flange that is extended from the inner side by a portion of a curved annular flange forming said structure.

14. The sealing joint according to claim 11 , wherein the structure for support and reinforcement is an integral part of the support ring and includes a portion of curved flange extending the radial flange on the inside.

15. The sealing joint according to claim 10 , wherein the annular structure for support and reinforcement, in the form of a circumferential flange, extends up to a short distance from the element that is to be sealed, the free edge of the flange being located at a distance from said element that is less than the thickness of the sealing lip.

16. The sealing joint according to claim 10 , wherein the structure for support and reinforcement is part of a second ring that comprises at least one radial flange that is extended from the inner side by a portion of a curved annular flange forming said structure.

17. The sealing joint according to claim 16 , wherein at least the part of the washer arranged on the radial flange of the support ring is sandwiched between the radial flange of the support ring and the radial flange of the second ring, optionally ensuring mechanical clamping of said washer part.

18. Sealing joint according to claim 16 , wherein one or more of the support ring and the second ring are made of an HLE-type plate.

19. The sealing joint according to claim 10 , wherein the structure for support and reinforcement is an integral part of the support ring and includes a portion of curved flange extending the radial flange on the inside.

20. The sealing joint according to claim 1 , wherein the washer covers all of the surfaces of the support ring that are directed toward the pressurized medium and toward a wall of a mounting housing of the sealing joint, against which the axial flange of the support ring comes to rest in an airtight manner.

Assignees

• Freudenberg Carl Kg

Inventors

• Girardot Thierry
• Lutaud Dominique
• Soudet Arnaud

Classifications

• F16J15/3268 Primary

  Mounting of sealing rings · CPC title

• F16J15/3228 Primary

  formed by deforming a flat ring · CPC title

• F16J15/3276

  with additional static sealing between the sealing, or its casing or support, and the surface on which it is mounted · CPC title

• F16J15/3252

  with rigid casings or supports · CPC title

• F16J15/002

  comprising at least two sealings in succession (F16J15/162, F16J15/40 take precedence) · CPC title