| 摘要 |
A parison handling device has a pair of opposed arms with each arm having at least a pair of grippers to selectively engage an extruded parison and transfer it to a second location such as to a mold of a blow molding machine. At least one gripper on each arm is both slidably and generally pivotally movable relative to the arm to facilitate initially engaging and gripping the parison and subsequent closing and stretching of a gripped end of the parison to more efficiently distribute the material of the parison such that after blow molding of the parison, the molded product has a substantially uniform wall thickness throughout. Preferably, a follower attached to each movable gripper is responsive to a profile or contour of a cam carried by each arm to guide the movement of the gripper corresponding to the profile of the cam. By adjusting or changing the profile of the cams, the slidable and pivotal movement of the grippers relative to the arm can be controlled to control the stretching of the parison and hence the distribution of the parison material as desired to form a particular product. By forming a product with a more uniform wall thickness, substantially less material is needed to form the product and therefore, the product may be formed at significantly lower cost.
|
