| 摘要 |
A garden umbrella of the solid wood pole type is designed to accommodate the pulley cord within a specially drilled cord passage located adjacent to a narrow neck slot extending longitudinally between the pulley, located at the top of the pole, and the hand crank near the bottom of the pole. A special drill bit is designed with both (a) narrow neck cutting edges for drilling the narrow neck slot and (b) relatively large main head cutting edges for drilling the cord passage in one simple manufacturing operation. The cord passage is sized to accommodate the pulley cord for up and down movement therein while the narrow neck slot is smaller than the cord thickness, thereby preventing the pulley cord from passing out of the pole through such narrow neck slot. |
