| 摘要 |
The present invention discloses an electric chain saw, which includes a casing (1) as well as a motor and the brake device thereof installed in the casing. The brake device includes the following parts: A brake drum (4) sleeved on and revolving together with a motor shaft; and a brake strap (5) sleeved on outer edge of the brake drum (4), with one end connected with a first brake unit and the other end with a second brake unit. The brake device in the present invention adopts two brake units, and can deal with a normal braking condition and an emergency braking condition, respectively. When one of the brake units fails, the electric chain saw of the present invention can be braked via the other brake unit, fully satisfying requirements on operation safety of the electric chain saw, characteristic of quick brake, simple operation, and sensitive action. Besides, compared to the prior art electric chain saw adopting such a brake mechanism as a clutch, a lever and a gear, the present invention is simple in the overall structure and less in the part quantity, more advantageous in miniaturization design of the electric chain saw. |
