Municipal casting frame and method of manufacturing same
US7712515B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 10, 2006 |
| Grant date | May 11, 2010 |
| Priority date | — |
| Expiry date | Oct 23, 2028 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE02D29/1427
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A municipal casting frame is provided with cast nut retainers that allow the frame to be used with or without a bolt-down cover. The frame defines one or more bolt holes of sufficient dimension to allow free passage of the cover bolts. The undersurface of the frame defines a cast nut retainer adapted to securely receive a nut. In one embodiment, the nut retainer includes protrusions that permit the nut to be snap-fitted into the nut retainer. In another embodiment, the nut retainer is configured to frictionally receive the nut in a wedging interaction. The present invention also provides a method for manufacturing a frame with integral cast nut retainers. The method generally includes the steps of (a) providing a core corresponding in shape to the bolt hole and the cast nut retainer, the cast nut retainer being configured to receive and retain a nut, (b) casting a frame in a mold about the core, (c) removing the cast frame from the mold and (d) removing the core from the cast frame. The process may also include the step of inserting a nut into the cast nut retainer in a direction that is in substantial coaxial alignment with the bolt hole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.