| 摘要 |
Soft-ice mixture, consisting of water or milk and commercially available powder, is frozen solid in a cylindrical container, then presented to a machine whereby the container is pressurized and which has an agitator that engages the surface of the solid to exert force along a narrow zone, whereby the material is locally melted. The momentarily melted material is immediately whipped by the agitator, before it refreezes. The agitator rotates at high speed (2,000 rpm) but advances into the material very slowly. For such action the agitator shaft is surrounded by an outer driver confined to rotation in one direction, with which the shaft has a splined connection, and the shaft in turn surrounds a threaded inner driver, with which the shaft has a threaded connection. For driving the agitator downward the inner driver is rotated in said direction, but slower than the outer driver; for driving it upward the inner driver is also rotated in said direction, but faster than the outer driver. Mechanism is described for automatic reversal of axial shaft movement and for automatic shut-off at the end of a cycle. |
