Apparatus for manufacturing magnet wire

• US 4,521,173 A
• Filed: 09/01/1983
• Issued: 06/04/1985
• Est. Priority Date: 04/29/1981
• Status: Expired due to Fees

• Current Assignee: Phelps Dodge Magnet Wire Company
• Original Assignee: Phelps Dodge Magnet Wire Company
• Inventors: Wright, Roger D., Disque, Donny R., Bodette, James E., Lausen, Verne H., Coon, Jessie H., Bultemeier, Keith D., Hilker, G. Daniel, Grimes, Jerry L.
• Primary Examiner(s): Thurlow, Jeffery
• Application Number:
  US06/528,564
• Time in Patent Office: 642 Days
• Field of Search: 425/113, 425/114, 425/131.1, 264/174, 264/134, 427/117-120, 118/405
• US Class Current: 425/113
• CPC Class Codes: H01B 13/16 by passing through or dipping in a liquid bath; by spraying

Abstract

A novel apparatus for manufacturing magnet wire in a continuous process by which coatings of a flowable resin material may be applied concentrically to a moving elongated filament in thickness of about 16 mils or less. The filament can be a bare copper or aluminum conductor having round or rectangular configuration or an insulated conductor upon which a top or an intermediate coat of material is desirably applied. Coatings of one-half mil and one mil also can be applied by the method of the invention. By the apparatus of the invention, magnet wire can be manufactured by continuously drawing the wire to size, annealing the wire, if necessary, insulating the wire with one or more coats of flowable resin material, curing the resin material, if necessary, hardening the resin material, and spooling the wire for shipment, without interruption at speeds limited only by the filament pay-off and take-up devices used. The apparatus of the invention utilizes the flowable resin material to center the filament in a die, the size of the die controls the thickness of the coat to be applied. In the apparatus of the invention, only the resin material being applied to the filament is in contact with the filament. Thus, the mechanical wear normally associated with centering dies used in extrusion processes and like devices is completely eliminated.

Claims

1. An apparatus for the manufacture of coated filaments such as magnet wire comprising a die apparatus, a filament pay-out device, a coated filament take-up device, said die apparatus being positioned between said pay-out and take-up devices to receive a moving filament trained from said pay-out device to said take-up device, said die apparatus including an entrance die and exit die and a die block, said die block being between said dies, said entrance die having an entrance opening and an exit opening, said entrance die having a throat portion and a diverging interior wall portion, said throat portion being smaller than said exit opening, said throat portion being larger than said filament, said throat portion being connected to said entrance opening, said throat portion being connected by said diverging interior wall portion to said exit opening, said exit die having an entrance opening and an exit opening, said exit die having a throat portion and a converging interior wall portion, said throat portion being smaller than said entrance opening, said throat portion being larger than said filament, said throat portion being connected to said exit opening, said throat portion being connected by said converging interior wall portion to said entrance opening, said die block having an interior passage communicating with said exit opening of said entrance die and said entrance opening of said exit die, said diverging interior wall portion of said entrance die and said interior passage of said die block and said converging interior wall portion of said exit die defining together a die chamber, said die chamber being fillable with flowable but hardenable material, said flowable material in said die chamber supporting said filament within said die apparatus concentricly of said throat portion of said exit die, a reservoir of said flowable material, operatively connected to said die apparatus for filling said central die chamber with said flowable material, said reservoir maintaining said flowable material within said die chamber at elevated pressures.

2. The apparatus of claim 1 including a filament heater disposed between said pay-out device and said die apparatus.

3. The apparatus of claim 2 wherein said filament heater heats said filament from about ambient temperature to about the decomposition temperature of said material at a position just prior to said filament entering said die apparatus.

4. The apparatus of claim 1 including a filament heater between said pay-out device and said die apparatus, a die heater, and a reservoir material heater.

5. The apparatus of claim 4 further comprising means including said filament and die apparatus and reservoir heaters for controlling the viscosity of said material in said die chamber.

6. The apparatus of claim 5 further comprising a take-up device driver, and a pay-out device brake.

7. The apparatus of claim 6 including means for hardening said material on said filament between said die apparatus and said take-up device.

8. The apparatus of claim 2 wherein said filament is selected from the group consisting of bare copper and bare aluminum conductors, and said filament heater includes a filament annealer.

9. The apparatus of claim 7 wherein said die apparatus, filling and maintaining means, and hardening means comprises a filament coating station, and wherein said apparatus includes a plurality of said coating stations in a spaced-apart relationship to each other and said take-up and pay-out devices.

10. The apparatus of claim 8 further comprising means for drawing said conductor into a conductor of smaller size, said drawing means being positioned between said pay-out device and said filament heater.

11. The apparatus of claim 1 wherein said reservoir pressurizes said material within said die chamber to pressures up to about 2,000 psi.

12. The apparatus of claim 1 including a second die apparatus located between said pay-out and take-up devices, said second die apparatus including entrance and exit dies and a die block, said die block being between said dies, said entrance die having an entrance opening and an exit opening, said entrance die having a throat portion and a diverging interior wall portion, said throat portion being smaller than said exit opening, said throat portion being larger than said filament, said throat portion being connected to said entrance opening, said throat portion being connected by said diverging interior wall portion to said exit opening, said exit die having an entrance opening and an exit opening, said exit die having a throat portion and a converging interior wall portion, said throat portion being smaller than said entrance opening, said throat portion being larger than said filament, said throat portion being connected to said exit opening, said throat portion being connected by said converging interior wall portion to said entrance opening, said die block having an interior passage communicating with said exit opening of said entrance die and said entrance opening of said exit die, said diverging interior wall portion of said entrance die and said interior passage of said die block and said converging interior wall portion of said exit die defining together a die chamber, said die chamber being fillable with flowable but hardenable material, said flowable material in said die chamber supporting said filament within said die apparatus concentricly of said throat portion of said exit die.

13. An apparatus for the manufacture of coated filaments such as magnet wire comprising a die apparatus, said die apparatus including entrance and exit dies and a die block, said die block being between said dies, said entrance die having an entrance opening and an exit opening, said entrance die having a throat portion and a diverging interior wall portion, said throat portion being smaller than said exit opening, said throat portion being connected to said entrance opening, said throat portion being connected by said diverging interior wall portion to said exit opening, said exit die having an entrance opening and an exit opening, said exit die having a throat portion and a converging interior wall portion, said throat portion being smaller than said entrance opening, said throat portion being connected to said exit opening, said throat portion being connected by said converging interior wall portion to said entrance opening, said die block having an interior passage communicating with said exit opening of said entrance die and said entrance opening of said exit die, said diverging interior wall portion of said entrance die and said interior passage of said die block and said converging interior wall portion of said exit die defining together a die chamber, said die chamber being fillable with flowable but hardenable material, said flowable material in said die chamber being disposed to support a filament smaller than said throat portions of said entrance and exit dies within said die apparatus concentricly of said throat portion of said exit die.

14. An apparatus for the manufacture of coated filaments such as magnet wire comprising a filament pay-out device, a coated filament take-up device, and a die apparatus between said pay-out and take-up devices, to receive a moving filament trained from said pay-out device to said take-up device, said die apparatus including entrance and exit dies and a die block, said die block being between said dies, said entrance and exit dies each having an entrance opening and an exit opening, said dies each having a throat portion, a converging interior wall portion and a diverging interior wall portion between a respective said entrance opening and a respective said exit opening, said throat portions being smaller than said openings, said throat portions being connected by respective said converging interior wall portions to respective said entrance openings, said throat portions being connected by respective said diverging interior wall portions to respective said exit openings, said die block having an interior passage communicating with said exit opening of said entrance die and said entrance opening of said exit die, said diverging interior wall portion of said entrance die and said interior passage of said die block and said converging interior wall portion of said exit die defining together a die chamber, said die chamber being fillable with flowable but hardenable material, to support a filament within said die apparatus concentricly of said throat portion of said exit die, said throat portions being larger than said filament and being interspaced from said filament when said filament is supported by said flowable material in said die chamber, said throat portions being sufficiently small to maintain said flowable material at elevated temperatures and pressures in said die chamber, and a reservoir for said flowable material operatively connected to said die apparatus for filling said die chamber with said flowable material and maintaining said supply of flowable material within said die chamber at elevated pressures.