Box level
US8375591B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 2010 |
| Grant date | Feb 19, 2013 |
| Priority date | — |
| Expiry date | Nov 5, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49947
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A level including an elongate hollow frame with two sidewalls and a topwall extending therebetween. A topnotch is formed by removal of a topwall section and adjacent sections of sidewalls including notch-defining bottom and side edges. A central vial is within the topnotch. The frame includes an inner horizontal wall extending between the sidewalls at the notch-defining bottom edges. A central-vial reference surface is formed in the inner horizontal wall parallel to the top and bottom measuring surfaces and defining a notch-bottom. The central vial is supported against the central-vial reference surface in accurate orientation without calibration. The central vial is secured with respect to the inner horizontal wall by mechanical fasteners. The frame further preferably includes an integral inner vertical wall extending between the top and bottom walls thereby reinforcing the frame along the frame length.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.