摘要 |
A driveshaft includes a center portion having a larger diameter, an end portion having a reduced diameter, and a diameter reducing portion positioned between the center and end portions. The reduced diameter end portion of the driveshaft is secured to a reduced diameter tube yoke. This facilitates the introduction of tooling during assembly of a universal joint. The driveshaft is formed by a method which involves first heat treating the driveshaft to a relatively soft temper, then swaging the end portion of the driveshaft, and then heat treating the driveshaft again to a relatively hard temper. In more detail, a driveshaft is provided having a predetermined first diameter, the driveshaft being heat treated to achieve a relatively soft temper so as to possess a desired elongation factor. This allows the end portion of the driveshaft to be swaged to reduce the diameter thereof to a second predetermined diameter. After swaging, the driveshaft is heat treated again to achieve a relatively hard temper to meet the strength requirements for use. |