Random lay wire twisting machine

• US 6,318,062 B1
• Filed: 11/13/1998
• Issued: 11/20/2001
• Est. Priority Date: 11/13/1998
• Status: Expired due to Fees

• Current Assignee: Donnelly Industries, Inc.
• Original Assignee: Watson Machinery International, Inc.
• Inventors: Doherty, John
• Primary Examiner(s): Stryjewski, William
• Application Number:
  US09/191,690
• Time in Patent Office: 1,103 Days
• Field of Search: 57/584.9, 57/585.2, 57/586.3, 57/586.5, 57/586.7, 57/586.8, 57/93, 572/06, 572/37, 572/64, 174/113.R
• US Class Current: 57/58.65
• CPC Class Codes: D07B 2201/2026 Pitch changing over length
• CPC Class Codes: D07B 2301/251 Twist
• CPC Class Codes: D07B 2301/3533 Amount of material
• CPC Class Codes: D07B 3/10 with provision for imparting more than one complete twist to the ropes or cables for each revolution of the take-up reel or of the guide member
• CPC Class Codes: H01B 13/0221 by a twisting take-up device

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.

Claims

1. Apparatus for twisting wires comprising:

means for feeding a pair of insulated wires into a wire twisting machine;

means for twisting said wires together at a constant speed to form a wire lay;

winding means for receiving and winding the twisted wires;

first drive means for driving said twisting means;

means for sensing the rate of speed of the wires being twisted;

means for generating a frequency signal proportional to said rate of speed;

means for receiving said signal and generating a randomly varying signal representative of a varying length of lay within predetermined limits;

means for generating a control signal from said randomly varying signal; and

second drive means for receiving said control signal and applying said control signal to said winding means to randomly vary the length of lay of the pair of twisted wires wound on said winding means.

2. The apparatus of claim 1 wherein:

said means for twisting said wires includes a pair of opposed bows, one of said bows carrying said pair of wires,

said winding means includes a capstan and take-up drum, and

said second drive means includes a stepping motor and slip rings applying said control signal to said stepping motor.

3. The apparatus of claim 2 wherein:

said means for generating a frequency signal includes an analog output module,

said means for generating a random signal includes;

a basic module generating a random number within predetermined limits,

a central processing unit providing a random signal from said random number representing a varying length of lay,

said means for generating a control signal includes an oscillator providing a varying frequency signal, and means receiving said control signal and supplying a varying direct voltage signal to said stepping motor.

4. The apparatus of claim 3 wherein said stepping motor applies said control signal to said winding means independent of the rate of the rotational speed of the wires being twisted.

5. The apparatus of claim 4 including a plurality of like apparatus twisting together a plurality of pairs of wires each having a randomly varying length of lay to form a cable.

6. The apparatus of claim 4 wherein said pair of insulated twisted wires has a randomly varying length of lay of between 0.2 to 0.9 inches.

7. Apparatus for twisting wires comprising:

means for feeding a pair of insulated wires into a wire twisting machine,

means for twisting said wires together at a constant rotational speed to form a wire lay,

first drive means for driving said twisting means,

means for drawing said twisted wires at a takeup speed from said means for twisting said wires,

means for winding said twisted wires,

means for sensing said takeup speed and generating a frequency signal proportional to said takeup speed,

means for receiving said signal and generating a randomly varying signal representative of a varying length of lay within predetermined limits,

means for generating a control signal from said randomly varying signal, and

second drive means for receiving said control signal and applying said control signal to said winding means to randomly vary the length of lay of the pair of twisted wires wound on said winding means.

8. A method of twisting pairs of insulated wires including the steps of:

feeding a pair of insulated wires into a wire twisting apparatus,

twisting the wires together at a predetermined rate of rotational speed to form a wire lay,

drawing the twisted wires,

directing the twisted wires onto a takeup means,

generating a randomly varying control signal representative of a varying lay length within predetermined limits, and

applying said control signal to automatically vary the takeup speed of the twisted wires to produce a randomly varying lay.

9. The method of claim 8 wherein said generating a randomly varying control signal and applying said control signal includes:

sensing the speed of the wires twisted onto the takeup means,

generating a frequency signal proportional to the rate of speed,

generating a control signal from said frequency signal, and

applying said control signal to the twisted wires directed onto said takeup means at a varying speed different from said predetermined rate of speed to randomly vary the length of lay of the pair of twisted wires within predetermined limits.

10. The method of claim 8 wherein said step of generating a randomly varying control signal and applying said control signal includes:

generating a randomly varying number within predetermined limits,

generating a randomly varying signal from said randomly varying number representing a varying length of lay,

generating a frequency signal from said randomly varying signal,

converting said frequency signal into a varying direct voltage signal, and

applying said direct voltage signal to a driving motor to control the speed of the wires directed onto the takeup means to provide said randomly varying length of lay between said limits.

11. A pair of insulated twisted wires having a randomly varying length of lay made by the method of claim 8.

12. Apparatus for twisting wires, comprising;

means for feeding a pair of insulated wires into a wire twisting machine,

means for twisting said wires together at a constant rotational speed to form a wire lay,

takeup means for receiving and winding the twisted wires, and

means for forming a randomly varying length of lay within predetermined limits including means coupled to said takeup means for automatically providing a randomly varying takeup speed for said wires.

13. The apparatus of claim 12 wherein said means providing a randomly varying takeup speed includes computer generator means generating random control signals controlling said takeup speed of the wire.

14. A method of twisting pairs of insulated wires including the steps of:

feeding a pair of insulated wires into a wire twisting apparatus,

twisting the wires together at a first rate of speed to form a wire lay,

drawing the twisted wires onto a takeup means, and randomly varying the takeup speed of the twisted wires to randomly vary the length of lay.