An improved plastics moulding machine comprises an oil cylinder, an injection ram in said oil cylinder adapted to move forward and backward by the actuation of the hydraulic system, and a shafting consisting of a main driving shaft, a transmission shaft and a screw rod; wherein a fixed protection sleeve is provided between the main driving shaft and the injection ram for preventing the friction therebetween.

An improved plastics moulding machine of the type comprising a hydraulic oil operating cylinder, an injection ram operating within said cylinder, and a rotating shaftsystem operating coaxially through the ram, wherein the improvement comprises: a fixed annular sleeve disposed between the ram and the shaft system, said shaft system operating through said sleeve, and an hydraulic seal provided between said ram and saidsleeve, whereby said shaft is isolated from the hydraulic oil.

The present invention relates to a plastics moulding machine particularly to a protection sleeve adopted between the main driving shaft and the injection ram of the moulding machine.

Several different types of plastics moulding machine have been known in the art, such as compression moulding machines, transfer moulding machines, injection moulding machines, and extruders etc. In earlier stages, the driving and injectionmechanism in a moulding machine are connected through gear means and operate in different directions, resulting in a noisy and inefficient operation.