Motion transfer mechanism

Abstract

A motion transfer mechanism has an elongated track upon which ride transfer mechanisms, to translate relative movements of the track into precise actuation of one or a plurality of transfer mechanisms. The track is of substantially unlimited length, in relation to the machine with which it is used, such as the press of a stacked injection mold, so as not to limit access to, or the range of motion of the press or other machine. The transfer mechanisms each rides upon the track, such that they can freely traverse its full length. The track has one or more spiral portions in its length, to translate relative longitudinal displacement into rotational movement. The angle of spiral can be varied, with local changes in angle, on order to achieve desired rates of acceleration, deceleration and periods of dwell in the operation of the output mechanism. The transfer mechanisms and the track mounting each have a simple enabling and disabling mechanism, which may be interconnected by a simple, manually operable, bang-bang hydraulic control, to enable an operator to effect operation or disablement of the system with a single hand motion. The system may be used with high cycle processes such as an injection mold, the track and motion transfer portions of the system being comprised exclusively of simple, robust, low stress mechanical components of extreme reliability, without power cylinders or other prime movers or limit switches, relays or other electronic components that collectively diminish system reliability. In the case of use of the system to introduce product take-off devices, such as suction cups between the open platen faces of a mold, the system may be secured in 'strap-on' relation to the sides of the respective components of the mold, to generate precise in-and-out actuation of the product handling devices between the mold interfaces during the ejection portion of the molding cycle in response to the normal cyclic movements of the mold.