GB365259A - Improvements in apparatus for textile testing - Google Patents

Abstract

365,259. Testing strength of textile threads. BOYCE, R. C. and BOYCE, B. A. M., 147, Ashby Road, Loughborough, Leicestershire. Dec. 5, 1930, No. 36693. [Class 106 (ii).] The test sample is initially positioned without any special precision in grips between which relative motion is to take place this motion being then produced and the sample positively loaded only when the grips have been separated by a predetermined distance when temporary and automatic connection is established between one travelling grip and one element of a two-part indicator the other element of which is controlled by the position of the second grip. A tubular carriage 2 is adapted to slide on a tubular bed 1 by means of a screwed spindle 3 driven by a motor 4 the screw being held against axial movement by a thrust bearing 5 and motion being transmitted to the carriage through a nut 6 formed in one with a key 7 extending through a slot in the bed 1. One end of a length of yarn 9 is held in a manually operated or spring grip 10 mounted on a base 12 slidable on a fixed seat 13, a loose pointer 11 being arranged as shown. The base 12 is loaded by a weight 14 on the arm of a wheel 15 attached by a flexible member 16 to the base 12. The yarn passes through an initially open grip 18 and through a tensioning device 20 on the carriage. After movement of the carriage has drawn the yarn through the tension device 20 until a predetermined length exists between the grips, a key 21 urged downwards by a spring 22 to bear on a bar 23 meets a gap 24 in the bar, and a pin releases a spring catch 26 normally holding up a lever 28 which then falls allowing the spring 29 to close the grip 18. The yarn is then placed under load measured by the lever 14 until breakage occurs, whereupon a catch 32 resting on the yarn falls and releases a lever 31 which is turned by a spring 33 to lift the key 21 out of the slot 24. The rod 23 then remains stationary and the extension of the yarn may be obtained by reading off the relative movement between the bar 23 and the pointer 11 on the scale 13 on the bar. The screw keeps on rotating until a collar 38 on the carriage engages a spring 40 abutting against a collar on a rod 34 which is moved to throw over a quick reversing switch 35. On return of the carriage the collar 38 engages the spring 39 abutting against a second collar on the shaft and the rod 34 is slid to engage a fixed stop 37 in which position the switch 35 stops the motor. The quick reversing toggle mechanism 36 at this time is just over the dead centre ready to reverse the switch when the stop 37 is moved by hand out of the path of the rod 34. The tensioning device 20 may be combined with the grip 18.