The present invention relates to seals, and more particularly to seal components for high speed shaft assemblies.
Seal assemblies often include annular components mounted upon a rotatable shaft and providing one or more surfaces against which seal non-rotatable or fixed components or upon which are mounted one or more runners providing such seal engagement surfaces. Particularly with high speed applications, such as shaft rotational speeds over 10,000 rpm or even 21,000 rpm, such seal components experience substantial radial growth due to the high centrifugal forces generated within the component. If sufficiently great, the radial growth of such seal components may cause eccentric operation and excessive shaft vibration due to resulting imbalance.
In one aspect, the present invention is a component for a seal assembly for sealing about a shaft, the shaft being rotatable about a central axis and having an outer circumferential surface. The seal component comprises an annular body having a centerline, first and second axial ends spaced apart along the centerline, an inner circumferential surface, and an opposing outer circumferential surface. The inner circumferential surface defines a central bore for receiving the shaft and is sized such that the body inner surface is frictionally engageable with the shaft outer surface to couple the component with the shaft. Further, at least three cavities extend axially from the body first axial end, are spaced circumferentially about the centerline and are located adjacent to the bore.
In another aspect, the present invention is again a component for a seal assembly for sealing about a shaft, the shaft being rotatable about a central axis and having an outer circumferential surface. The seal component comprises an annular body having a centerline, first and second axial ends spaced apart along the centerline, an inner circumferential surface, and an opposing outer circumferential surface. The inner circumferential surface defines a central bore for receiving the shaft and is sized such that the body inner surface is frictionally engageable with the shaft outer surface to couple the component with the shaft. At least three cavities extend axially from the first axial end and are spaced circumferentially about the centerline. Each cavity is located adjacent to the bore so as to define a separate centering body portion between a radially innermost surface section of the cavity and an axially-extending centering surface section of the body inner circumferential surface located radially inwardly of the cavity. As such, any radial growth of each one of the centering body portions is lesser than concurrent radial growth of remaining portions of the body during rotation of the shaft.
The foregoing summary, as well as the detailed description of the preferred embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings, which are diagrammatic, embodiments that are presently preferred. It should be understood, however, that the present invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:
Certain terminology is used in the following description for convenience only and is not limiting. The words “inner”, “inwardly” and “outer”, “outwardly” refer to directions toward and away from, respectively, a designated centerline or a geometric center of an element being described, the particular meaning being readily apparent from the context of the description. Further, as used herein, the words “connected” and “coupled” are each intended to include direct connections between two members without any other members interposed therebetween and indirect connections between members in which one or more other members are interposed therebetween. The terminology includes the words specifically mentioned above, derivatives thereof, and words of similar import.
Referring now to the drawings in detail, wherein like numbers are used to indicate like elements throughout, there is shown in
Further, a separate centering body portion 20 is defined between each cavity 18, specifically a radially innermost surface section 19 of the cavity 18, and an axially-extending centering surface section 21 of the body inner circumferential surface 14 located radially inwardly of the particular cavity 18. Preferably, each one of the cavities 18 is formed as an arcuate slotted opening, such that each centering body portion 20 is formed as a relatively thin web of material. More specifically, a radial thickness rT (
By providing the annular body 12 with the cavities 18, any radial growth of each one of the centering body portions 20 formed thereby is substantially lesser than concurrent radial growth of remaining portions 22 of the body 12 (i.e., portions without a cavity 18) during rotation of the shaft 1, as depicted in
By maintaining the seal component 10 centered about the axis AC during high speed rotation of the shaft 1, dynamic radial imbalance is minimized (or even eliminated) and eccentric operation is avoided, which substantially eliminates the primary source of vibration of the shaft 1. Having described the basic components and features above, these and other aspects of the present seal component 10 are described in further detail below.
Referring to
Further, the outer circumferential surface 16 of the annular body 12 is preferably formed of a plurality of axially-spaced, adjacent surface sections 17 each having an outside diameter (not indicated) with a value greater or lesser than the value of the outside diameters of the other surface sections 17. Such varying outside diameters enable the installation or mounting of different seal elements or parts about the seal component 10. Preferably, the annular body 12 of the seal component 10 includes one or more of a seal runner surface (not shown), a mounting surface 32 for a seal runner 3, an axial-extending annular mounting groove 34 for an axial face seal member 4, and a plurality of radially-outwardly extending ridges 36 for providing a portion of a labyrinth seal. However, the seal component 10 may be formed without any of these features or with any other appropriate seal features or structures.
Referring particularly to
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as generally defined in the appended claims.
Number | Name | Date | Kind |
---|---|---|---|
3285614 | McClenathan | Nov 1966 | A |
4416458 | Takenaka | Nov 1983 | A |
5388843 | Sedy | Feb 1995 | A |
5722665 | Sedy | Mar 1998 | A |
6428012 | Amaral | Aug 2002 | B1 |
7051694 | Warnecke | May 2006 | B2 |
20100201074 | Haynes | Aug 2010 | A1 |
20130234399 | Justak | Sep 2013 | A1 |
20180128366 | Weng | May 2018 | A1 |
20180258780 | Fan | Sep 2018 | A1 |
20190113080 | Kamiya | Apr 2019 | A1 |
20190376558 | Kimura | Dec 2019 | A1 |
Number | Date | Country |
---|---|---|
3453928 | Mar 2019 | EP |
WO-2016088659 | Jun 2016 | WO |
Entry |
---|
Search report from the British patent officer in related application No. GB2017317.5 dated Mar. 22, 2021. |
Number | Date | Country | |
---|---|---|---|
20210231216 A1 | Jul 2021 | US |