Patent Application
20160186839
The invention relates to a tensioner axial seal, and more particularly, to a tensioner having an axial seal engaged with the receiving portion, the axial seal comprising members extending in an axial direction (A-A), the members in sliding contact with a pivot arm surface.
Labyrinth seals are an established technology for tensioners. However, such seals do not comprise flexible members and therefore can be severely limited in their ability to prevent infiltration of debris into a tensioner body. This can lead to premature wear and failure.
Brush seals are well established in turbomachinery. They are used in power turbines to prevent debris entry and to provide a pressure barrier to reduce steam and seal air leakage.
Representative of the art is U.S. Pat. No. 8,777,563 which discloses a brush seal assembly for turbomachinery having a rotor can include a stationary seal component, a floating seal component coupled to the stationary seal component and circumferentially angled bristles arranged in a bristle pack, disposed in the floating seal component and extended axially with respect to the rotor.
What is needed is a tensioner having an axial seal engaged with the receiving portion, the axial seal comprising members extending in an axial direction (A-A), the members in sliding contact with a pivot arm surface. The present invention meets this need.
The primary aspect of the invention is to provide a tensioner having an axial seal engaged with the receiving portion, the axial seal comprising members extending in an axial direction (A-A), the members in sliding contact with a pivot arm surface.
Other aspects of the invention will be pointed out or made obvious by the following description of the invention and the accompanying drawings.
The invention comprises a tensioner having an axial seal comprising a base having a receiving portion, the receiving portion extending about a circumference of the base, a pivot arm pivotally engaged with the base, the receiving portion in continuous proximity to the pivot arm, a spring urging a movement of the pivot arm, and an axial seal engaged with the receiving portion, the axial seal comprising members extending in an axial direction (A-A), the members in sliding contact with a pivot arm surface.
The accompanying drawings, which are incorporated in and form a part of the specification, illustrate preferred embodiments of the present invention, and together with a description, serve to explain the principles of the invention.
In a typical installation a pulley (not shown) is journalled to the pivot arm at threaded portion H.
Brush seal 40 is mounted to base 20 in receiving portion 21. Receiving portion 21 is disposed about an outer circumference of base 20. The receiving portion is configured to be in continuous proximity to the pivot arm 10.
Brush seal 40 is circular and comprises a flexible base portion 41. Bristles 42 extend in an axial direction from circular base portion 41. Bristles 42 are flexible to accommodate variations in the form of the pivot arm surface. The axial direction is parallel to the axis of rotation of the pivot arm A-A.
Bristles 42 are in sliding contact with surface 11 of pivot arm 10, thereby forming a seal about the entire perimeter of the base.
In yet another alternate embodiment members 43 or bristles 42 extend in a radial direction either inward or outward from an axis of rotation A-A. The radial direction is normal to the axial direction.
Although forms of the invention have been described herein, it will be obvious to those skilled in the art that variations may be made in the construction and relation of parts and method without departing from the spirit and scope of the inventions described herein.
