injection unit 18 the mould closing unit designated 23 as a whole which has a tool clamping plate 25 which can be moved on horizontal pillars 24 relative to the fixed tool clamping plate 20 is also arranged on the machine frame 16 fastened between the tool clamping plates 20 25 is the injection mould not shown in more detail in the drawings with the two mould halves the pillars are mounted in a support plate 26 on the rear of the moveable tool clamping plate 25 remote from the fixed tool clamping plate 20 provided between the support plate 26 and the moveable tool clamping plate 25 is a hydraulically driven knee lever mechanism 27 with the aid of which the opening and closing of the moveable tool clamping plate 25 and the keeping shut of the mould during the injection moulding process are brought about the knee lever mechanism 27 can be actuated by means of a hydraulic cylinder 10 which can be activated by means of er valves 5 as illustrated in more detail with the aid of fig3 the electrorheological hydraulic fluid itself is provided by means of a hydraulic pump 12 mounted below the injection unit 21 in.