Patent GB-750086-A (GB)
Title: Method of and apparatus for automatically controlling the uniformity of weight per unit length of the fibrous output from a carding engine or some part thereof
Inventor: CASSIE ARNOLD BLATCHFORD DAVID
IPC: D01G23/06
Filed: 1953-01-31
Abstract: 750,086. Carding-engines and feeding apparatus therefor; roller arrangements in textile spinning &c. machines; coiling slivers. WOOL INDUSTRIES RESEARCH ASSOCIATION. Jan. 22, 1954 [Jan. 31, 1953], No. 2828/53. Classes 120 (1), 120 (2) and 120 (3). [Also in Group XXXV] The weight per unit length of the fibrous output delivered by a textile carding engine or by any part other than the condenser doffer of a card producing slubbing or its equivalent on the condenser system is automatically controlled by measuring, at any convenient and suitable place in the card, the weight per unit length of the sliver by means of a measuring device which operates means to control the speed of mechanism by which the material is fed into or delivered from the card or part thereof, such speeds being varied relative to that of the parts, e.g. drafting rollers, immediately following or preceding the mechanism in a manner proportional or related in known or determinable manner, within the required limits, to the variation determined by the measuring device. The measurement may be effected mechanically e.g. by passage of the sliver between a pair of rollers one grooved and the other ridged circumferentially, by air gauging, by electrical means responsive to a beam of light or other form of radiation, or by direct measurement of electrical properties such as resistance or capacitance. The measurement may be effected at an intermediate feed, e.g. Scotch, ball and bank, or Apperley-type feed, in which case the controlled mechanism may be the feed sheet and/or hopper or lap or equivalent feed mechanism; alternatively, and especially for any part of a card delivering an independent fibrous output which is not being fed simultaneously to a further part or other machine, the ball-making or equivalent mechanism is controlled. In application of the invention, the ratio of the speeds of two parts or members of a card may be controlled by employing mechanical lever systems, with or without amplification in a mechanical torque, electrical relay, electronic, hydraulic, or pneumatic amplifier, the output of which operates a variable speed ratio gear. Integral and " derivative " modes of control may be superimposed in known manner. Smooth transfer of the controlled material between parts may be ensured by the provision of a container which continuously accumulates, holds, and then discharges a reserve of such material. In the apparatus shown, sliver 5 as carried by a Scotch feed 1 passes between measuring rollers comprising a driven rigidly mounted roller 2 and a floating spring- or self-loaded roller 3 which actuates pivoted levers 4 and 5 to open or close contacts 6 in an electrical circuit 7 which includes a device for actuating a variable speed ratio unit 8, in accordance with deviations from a predetermined datum of the weight per unit length of sliver as detected by the roller 3, to vary the speed of a driven roller of a drafting pair 9, 10 which always have a higher speed than the rollers 2, 3, and deliver the sliver to an accumulator device consisting of a cylindrical can 11 having a conical end plate through a hole 12 in which the sliver emerges. The can may rotate about a vertical axis to give the sliver some twist and coil it in the can by an off-centre or traversed guide 13.