Expandable band and locking mechanism
The expandable band is used to secure a sealing element within a generally cylindrical structure, such as a pipe or manhole, or other round hole. The expandable band includes a band body having a first band end portion and a second band end portion. The first band end portion includes a plurality of slots, and the second band end portion includes a first and second aperture. A locking member is a separate element adapted to fit within the first and second apertures and includes a first tab for extending through the first aperture and into one of the plurality of slots to lock the expandable band at the desired diameter and a second tab for engaging the second aperture. The second tab is designed not to interfere with the first band end portion while expanding the band. The locking member may also include at least one rib or protrusion.
1. An expandable band comprising: a band body having a first band end portion and a second band end portion, wherein said first band end portion and said second band end portion overlap to form a generally annular shape; a plurality of sequential slots disposed in said first band end portion of said band body; a first and a second aperture disposed in said second band end portion; a locking member having a first and a second tab disposed proximate a first and a second end portion of said locking member, said first tab adapted to extend through said first aperture in said second band end portion and into one of said plurality of slots to lock said expandable band at a desired diameter, said second tab adapted to secure said locking member against said second band end portion; and an end section disposed proximate said second band end portion of said band extending beyond said first tab of said locking member.
2. The expandable band of claim 1 wherein said band body includes a base portion and side portions extending from said base portion, and wherein said plurality of slots are disposed in said base portion of said band body.
3. The expandable band of claim 1 wherein said first tab forms an obtuse angle with respect to a plane tangential to said second band end portion of said band body.
4. The expandable band of claim 1 wherein said band body has a generally W-shaped cross section.
5. The expandable band of claim 4 wherein said first and second band end portions of said band body have said generally W-shaped cross section.
6. The expandable band of claim 1 wherein said band body includes a base portion and at least two V shaped side portions extending from said base portion, and wherein said plurality of slots are disposed in said base portion of said band body.
7. The expandable band of claim 1 wherein said locking member is made from a material resistant to bending.
8. A sealing system comprising: a resilient sealing member; and an expandable band comprising: a band body having a first band end portion and a second band end portion, wherein said first end and said second end overlap to form a generally annular shape such that said expandable band contacts said resilient sealing member; a plurality of slots disposed in said band body proximate said first end; a first and a second aperture disposed in said second end; a locking member having a first and a second tab disposed proximate a first and a second end portion of said locking member, said first tab adapted to extend through said first aperture in said second band end portion and into one of said plurality of slots to lock said expandable band at a desired diameter against said resilient sealing member, said second tab adapted to secure said locking member against said second band end portion, wherein said resilient sealing member provides a resilient backing for said locking member; and an end section disposed proximate said second end of said band extending beyond said first tab of said looking member.
9. The expandable band of claim 8 wherein said band body has a generally W-shaped cross section.
10. The expandable band of claim 8 wherein said first and second band end portions of said band body have said generally W-shaped cross section.
11. The expandable band of claim 8 wherein said band body includes a base portion and at least two V shaped side portions extending from said base portion, and wherein said plurality of slots are disposed in said base portion of said band body.
12. The expandable band of claim 8 wherein said locking member is made from a material resistant to bending.