| 摘要 |
This invention relates to a novel method of manufacturing an integral manifold for a multi-cavity injection molding system. The manifold has a melt passage which follows a tortuous path and is formed by milling matching grooves without any sharp bends in opposite surfaces of two plates which are then secured together. The manifold is formed of tool steel and also has an electrical heating element which is cast into a channel in its upper surface. The two plates are brazed together and the heating element is cast in the channel in a common heating step under a partial vacuum in a vacuum furnace. A highly conductive copper alloy flows around the heating element and diffuses by capillary action between the opposed surfaces of the plates to form a metallurgical bond with them to improve heat transfer away from the heating element and avoid leakage from the melt passage. This method has the advantage that it reduces the time required to make a manifold having a melt passage which branches to several outlet openings and it avoids the sharp bends in the melt passage necessarily associated with the previous drill and plug method, thereby providing a natural rheological balance. |
