公开(公告)号：US3624025A

公开(公告)日：1971-11-30

申请号：US3624025D

申请日：1969-09-03

Applicant: BRITISH INSULATED CALLENDERS

Inventor： TWIST REGINALD JAMES

IPC: B29C47/10 ,  B29C47/92 ,  G05D5/03 ,  B29F3/06 ,  B29F3/10

CPC classification number: B29C47/92 ,  B29C47/0014 ,  B29C47/1036 ,  B29C2947/92085 ,  B29C2947/92104 ,  B29C2947/92142 ,  B29C2947/92161 ,  B29C2947/9218 ,  B29C2947/9219 ,  B29C2947/92438 ,  B29C2947/9258 ,  B29C2947/9259 ,  B29C2947/926 ,  B29C2947/92609 ,  B29C2947/92685 ,  B29C2947/92847 ,  B29C2947/92876 ,  B29C2947/92933 ,  B29C2947/92961 ,  G05D5/03

Abstract: The operation of an extrusion machine is controlled to obtain a constant cross section in the extrudate without the need to make measurements upon it. The machine is fed by a controlled feeding device which discharges into a reservoir that has a capacity sufficient to ensure that the machine is choke fed, and the reservoir is provided with means, such as a narrow neck, to amplify variations in the level so that unacceptable changes are immediately indicated. Signals representing a rate of feed to the reservoir and the line speed are obtained and the relationship between the feed rate and the speed of the machine and between the feed rate and the line speed are adjusted respectively to maintain a constant level in the reservoir and to establish a constant relationship so that the rate of extrusion of material is kept constant.

公开(公告)号：GB1217187A

公开(公告)日：1970-12-31

申请号：GB4281568

申请日：1968-09-09

Applicant: BRITISH INSULATED CALLENDERS

Inventor： TWIST REGINALD JAMES

IPC: B29C47/10 ,  B29C48/92 ,  G05D5/03

Abstract: 1,217,187. Controlling extrusion processes. BRITISH INSULATED CALLENDER'S CABLES Ltd. 9 Sept., 1969 [9 Sept., 1968], No. 42815/68. Heading B5A. In a method of controlling an extrusion process, a controlled feeding device 1, such as a weight or volume dispenser, feeds material to a reservoir 3 having a narrow glass neck 4 to display and amplify variations in the level of material in the reservoir, a signal representing the rate of feed is obtained from a transducer 15, a signal representing the line speed is obtained, e.g. from a capstan 18, and the rate of feed and/or the line speed are adjusted to maintain the level in the reservoir and the relationship between the signals constant such that the cross-sectional area of the extrudate remains substantially constant. The term, line speed, may apply to the speed at which a core being covered passes through the extruder or the speed at which extrudate is taken up, e.g. by a capstan. As shown, a volume dispenser 1 is associated with a sampler 7 which automatically calibrates the feed signal. The feed signal is applied to a voltmeter 17, previded with a set of changeable scales marked to indicate the correct line speed via a calibrating potentiometer 16. An indicator 19 shows the actual line speed. In a second embodiment, Fig. 2 (not shown), voltmeter 17 is replaced by an analogue/digital converter (20) which supplies a digital feed signal (A) to a display (21). A digital signal (B) representing the line speed is also fed to display (21) which shows signal (A), signal (B) or signal (A)/signal (B), the latter being proportional to the weight per unit length of material in the extrudate. In a third embodiment, Fig. 3 (not shown), the feed signal for potentiometer 16 is applied directly to a haul-off speed control (23) and the level in neck 4 is measured by a capacitance probe (24) which applies a signal to the speed controller (25) of feeding device motor 14 or alternatively to extrusion motor (26). Generally, reservoir 3 is provided with a vibrator 42 and overflow mechanism 9-11. The invention is particularly directed to the coating of cores with PVC.