Random lay wire twisting machine

Abstract

A wire twisting machine and method provide a randomly varying lay to pairs of twisted wires forming a cable. A pair of wires are fed into a motor driven bow mechanism which twists the wires at a given rate of speed. The bow winding speed is sensed to provide a signal to a control system employing a computer which generates a randomly varying signal between a selected minimum and maximum range. The random signal is applied to an oscillator which provides a varying frequency signal to a power supply unit. A pulsed direct voltage signal then controls a stepping motor which applies the randomly varying lay signal to vary the speed of the capstan winding the wires with respect to the independent bow speed. This varies the length of lay of the twisted wires within controlled limits.

What is claimed is:  
     
         1 . A pair of insulated twisted wires having a constantly randomly varying length of lay within predetermined limits produced by the process comprising: 
 feeding a pair of insulated wires into a wire twisting machine,    twisting said pair of wires together at a constant rotational speed,    drawing said pair of twisted wires,    directing said pair of twisted wires onto a takeup means, and    randomly varying the takeup speed of said pair of twisted wires between predetermined limits to produce a constantly randomly varying length of lay of said pair within predetermined limits.    
     
     
         2 . A pair of insulated twisted wires according to    claim 1    including, 
 providing a signal representative of said constant rotational speed of the twisted pair of wires,  
 processing said signal to provide a random signal representative of a varying length of lay between minimum and maximum lengths,  
 applying said random signal to said takeup means to produce said constantly randomly varying length of lay between said limits.  
 
     
     
         3 . Pairs of insulated twisted wires, each pair having a constantly randomly varying length of lay within predetermined limits produced by the process comprising: 
 feeding pairs of insulated wires into respective wire twisting machines,    twisting said pairs of wires together at a constant rotational speed,    drawing said pairs of twisted wires,    directing said pairs of twisted wires onto takeup means, and    randomly varying the takeup speed of said pairs of twisted wires between predetermined limits to produce a constantly randomly varying length of lay of said pairs within predetermined limits.