Compact hydraulic drive for die closing unit of injection molding machine

Abstract From the Canadian patent

A hydraulic actuator assembly for a push-type die closing unit of an injection molding machine capable of producing rapid die opening and closing movements with a small volume of pressurized fluid and an elevated die closing pressure in the closed die position, the assembly comprising a central power cylinder with a selectively bypassable power piston and two parallel, diametrally oppositely arranged single-acting travel cylinders. The low-pressure space on the forward side of the power piston is open to the pressure spaces of the two travel cylinders and the, total effective area of these pressure spaces is larger by a relatively small amount, than the area of the highpressure space to the …