| 摘要 |
<p>An injection molding apparatus and method are provided in which the rate of material flow during an injection cycle is controlled. According to one preferred embodiment, an injection molding apparatus is provided that includes a manifold (231), at least one injection nozzle (215) coupled to the manifold, an actuator, and a valve pin (200) adapted to reciprocate through the manifold and the injection nozzle. The valve pin (200) has a first end coupled to the actuator, a second end that closes the gate (211) in a forward position, and a control surface (205) intermediate said first and second ends for adjusting the rate of material flow during an injection cycle. Retracting the valve pin tends to decrease the rate of material flow during the injection cycle and displacing the valve pin toward the gate (211) tends to increase the rate of material flow during the injection cycle.</p> |
