| 摘要 |
<p>1,108,400. Extruder drive systems. W. SPINDLER. 16 Dec., 1965 [18 Dec., 1964], No. 53464/65. Heading B5A. A screw extrusion moulding machine comprises an axially reciprocable screw 2 rotated by a hydraulic motor 4 and reciprocated by hydraulic actuation of a piston 6. The output of the machine is controlled by a pressure measuring device 21 provided with contacts 23a, 23b connected to electrohydraulic valves 25a, 25b via electro-magnets 24a, 24b. If the pressure in chamber 17 of cylinder 5 falls below a predetermined value, contact 23a is actuated and valve 25a is opened to allow a pump 8 to deliver hydraulic medium via lines 26a, 28 and 22. If the pressure in chamber 17 increases above the predetermined value, i.e. the backpressure on screw 2 is too great, contact 23b is actuated, valve 25a closes, valve 25b opens, and hydraulic medium returns from chamber 17 via lines 22, 28 and 26b to reservoir 7. Motor 4, supplied with hydraulic medium by pump 8 from reservoir 7 is provided with a revolution counter 12 and indicator 13 and is controlled by a pressure sensitive device 33 situated between an annular choke 15 and extrusion nozzle 16. Device 33 is connected to a further pressure measuring device 34, similar to device 21, which by a line 41 controls the operation of a flow-rate meter 10 via a motor 42. To compensate for change of nozzle 16, device 34 is also connected to a motor-position meter 29 via quotient meters 43, 45 and an indicator 31 which may be calibrated in viscosity values. If a single nozzle is used quotient meter 45 may be dispensed with, Fig. 2 (not shown), and if only one pressure measuring device is used this may be incorporated as shown in Fig. 3 (not reproduced). Meter 29 may transmit visual or audio-signals. Barrel 1 is provided with electric heaters 19a-19c.</p> |
