| 摘要 |
<p>A load is applied to the spring, which is then heated until the spring relaxes and the load is reduced to a prescribed value of which the heating process is automatically interrupted; the residual load is then removed and the spring cooled, or a coolant is used on the spring while the residual load is still present. In the pref. appts., a plunger is used to compress the spring using a specific load. Electric resistance heating of the spring is then used intil the spring collapses by a specified amt. so that a limit switch cuts off the electric heating current. The plunger is operated pneumatically or hydraulically and the limit switch is triggered by the movement of the plunger; wts. can be placed on the plunger to provide the initial load. Esp. to adjust the properties of valve springs before the latter are used in IC engines.</p> |
