Cordless grass trimmer having removable battery pack
US3973378A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 1975 |
| Grant date | Aug 10, 1976 |
| Priority date | — |
| Expiry date | Mar 18, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S30/01
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An upright cordless grass trimmer incorporated incoporates fixed multi-toothed bottom blade and plural sets of top blades which oscillate over the bottom blade to achieve cutting. The sets of top blades are driven by a motor through a gear and cam mechanism and are synchronized so that one top blade set cuts at a different time in the cycle from the other set to achieve a counterbalancing and load leveling effect. A clutch mechanism absorbs abrupt blade stoppage and shock situations and a rechargeable battery pack is releasably received by an elevated cavity in a shroud which mounts over the motor and drive mechanism. An upright handle and electrical control means are attached to the trimmer which allows the operator to operate the trimmer in an upright position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.