Multi-purpose trimmer, edger and sweeper with or without support cart, and with enhanced inertia head
US6415585B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Aug 10, 1999 |
| Grant date | Jul 9, 2002 |
| Priority date | — |
| Expiry date | Aug 10, 2019 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA01D34/416
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A string trimmer having a head with aerodynamic cutting line with a long beam axis and a pitch angle may be used for both vegetation cutting and as a blower. A gear box may be provided for changing the gear ratio from the engine or motor to the head depending upon the pitch angle. Optimum cutting operation is provided with a pitch angle of about 0-10°, and when used as a blower the optimum pitch angle is between about 15-45° upward. The string trimmer may be mounted on a cart having a bottom frame with at least three wheels, first and second adjustable length arms each rotatably mounted by the substantially vertical axis and having a free end, and a clamp at the first arm free end for clamping the shaft of the string trimmer, and a clamp or flexible band or cord at the end of the second arm, typically also for engaging the string trimmer shaft to provide substantially 360° freedom of movement thereof. In order to maximize cutting efficiency the trimmer head may have a polar moment of inertia of about 1.6-2.4 inch pounds second squared, which may be provided by the inherent construction of the head, or by lead tape placed at various locations on the head.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.