| 摘要 |
PURPOSE:To reduce the generation of burr and to enhance the durability against pull-out force and turning torque by using an insert metal fitting wherein a specific groove is provided to an insert part and inserting said metal fitting by utilizing ultrasonic vibration. CONSTITUTION:Either one of or both of a lateral groove 6 and a longitudinal groove 7 are provided to the insert part of an insert metal fitting 1. The lateral groove 6 mainly contributes against the pull-out of the insert part and the longitudinal groove 7 mainly contributes to an increase in the holding force of the insert part to rotation. It is necessary to set the mean width of each of the grooves 6, 7 to 0.2-3mm and the mean depth thereof to 0.2-3mm. In inserting the inserting metal fitting under pressure to fix the same, the insert metal fitting is aligned with the hole part of a resin molded product to be inserted in said hole part under pressure while ultrasonic vibration is applied by an ultrasonic welding machine and the thermoplastic resin (the inner surface of the hole part) in contact with the insert metal fitting under pressure is melted by friction heat due to vibration and partially or entirely allowed to fill the grooves 6, 7 provided to the insert metal fitting to more strongly fix the insert metal fitting. |
