Tape measure with epicyclic gear drive for tape retraction
US11427434B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 13, 2020 |
| Grant date | Aug 30, 2022 |
| Priority date | — |
| Expiry date | Nov 27, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2003/103
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A tool, such as a tape measure, including a spring-based retraction system is shown. The retraction system utilizes an epicyclic gear train coupled between the tape blade winding reel and a rotating arbor or axle within the tape measure. A spiral spring has an outer end coupled to the reel and an inner end coupled to the axle. The gear train may be a reduction gear train such that the axle rotates slower than the reel. By coupling the spiral spring between the gear train input and gear train output, high energy density springs may be used, which may allow for decrease in housing size, increase in tape length or thickness for a given housing size, and/or advantageous retraction speed control.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.