Chain saw with a stopping device
US4782593A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1987 |
| Grant date | Nov 8, 1988 |
| Priority date | — |
| Expiry date | Feb 27, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16D59/00
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A portable chain saw wherein the motor drives a hub which is coaxial with a cylindrical portion of the shaft for one sprocket wheel of the chain. A coil spring is wound around the hub and the cylindrical portion to normally transmit torque from the hub to the shaft and to brake the shaft in response to its disengagement from the hub as a result of pivoting of a guard for one hand of the operator. The guard is pivoted by the one hand when the chain saw wobbles or performs other undesirable movements. The coil spring, the hub and the cylindrical portion together constitute a so-called wrap spring clutch wherein the spring rotates with the hub until arrested by a pin-shaped decoupling element which is movable radially of the hub by a second spring in response to pivoting of the guard.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.