Abstract: The accumulator of an extrusion blow molding machine is constructed to include a stroke positioner that comprises inter-engaging, threaded components that enable the piston of the programming cylinder to be adjusted relative to the inner rod of the programming system in the accumulator assembly. Since the inner rod ultimately connects to the die pin, this adjustment directly determines the position at which the piston in the programming cylinder will close off the die gap. In particular, the components of the programming system can be adjusted so that the die gap is closed just as the piston of the programming cylinder reaches the limit of its stroke.

Abstract: An accumulator head is convertible to alternate capacity ranges by providing a construction that has a segmented barrel with a matching ram in the purging system. More specifically, the accumulator barrel is divided into upper and lower segments so that the accumulator chamber is bounded by the lower barrel segment. The inner diameter of the lower barrel segment matches the outer diameter of the ram, and the length of the lower barrel segment corresponds roughly to the range of movement of the ram. With this accumulator construction, it is possible to change the working volume of the internal accumulator chamber by simply changing two parts, i.e., the lower barrel segment (inner diameter) and the ram (outer diameter). In addition, the two piece accumulator barrel design facilitates a more economical construction since the lower segment (where most of the wear occurs) can be made of a wear resistant grade of steel, while the upper segment can be manufactured from a lower cost, more easily machined material.