| 摘要 |
The present invention concerns an improved safety bearing which rotates naturally in one direction but rotates at low speed in the other direction and is braked to stop high-speed rotation, and a shutter control apparatus using the same. The safety bearing according to the present invention has a structure that stops high-speed rotation, thus it can be used as a high-speed fall preventive unit for a mechanism and system such as a shutter or elevator or crane, which need to prevent high speed falls. Particularly, a shutter control apparatus applying the safety bearing according to the present invention can prevent safety accidents because the safety bearing is installed in a driven sprocket connected to a rotary shaft that opens and closes the shutter by moving it up and down and stops the shutter from falling by stopping high-speed rotation of the driven sprocket when the shutter starts to fall at high speed. |
