Double end servo scroll pattern attachment for tufting machine

• US 6,550,407 B1
• Filed: 08/23/2002
• Issued: 04/22/2003
• Est. Priority Date: 08/23/2002
• Status: Active Grant

• Current Assignee: Tuftco Corporation
• Original Assignee: Tuftco Corporation
• Inventors: Frost, Steven, Prichard, Richard
• Primary Examiner(s): NERBUN, PETER P
• Application Number:
  US10/227,376
• Time in Patent Office: 242 Days
• Field of Search: 112/475.23, 112/80.73, 112/80.23, 112/80.01, 112/475.01, 112/220
• US Class Current: 112/475.23
• CPC Class Codes: D05C 15/18 Thread feeding or tensioning arrangements
• CPC Class Codes: D05C 15/32 by altering the loop length

Abstract

The present invention provides a double end yarn drive pattern attachment for tufting machines characterized by independent servo-motor control of yarn feed rolls capable of increased torque to carry multiple yarn ends on a single feed roll, thereby economically retaining many advantages of a single end pattern attachment.

Claims

1. In a multiple needle tufting machine adapted to feed a backing fabric longitudinally from front to rear through the machine having a plurality of spaced needles aligned transversely of the machine for reciprocal movement through the backing fabric by operation of a rotary main drive shaft, a yarn feed mechanism comprising:

(a) a support having a mounting surface extending longitudinally away from the tufting machine;

(b) at least about five servo motors, longitudinally spaced and attached to the mounting surface, wherein each servo motor is in communication with a yarn feed roll;

(c) a controller which electronically receives rotational position information for the main drive shaft and electronically sends corresponding ratiometric pattern information to the servo motors; and

(d) at least about five pluralities of yarns proceeding from a yarn supply through the yarn feed mechanism to the plurality of spaced needles, such that each of the pluralities of yarns is fed by a yarn feed roll in communication with a distinct servo motor, and every yarn within each plurality of yarns is fed to an adjacent needle.

3. The yarn feed mechanism of claim 1 wherein the support is arched.

4. The yarn feed mechanism of claim 1 wherein the pluralities of yarns consist of two yarns.

5. The yarn feed mechanism of claim 1 wherein the pluralities of yarns comprise no more than five yarns.

6. The yarn feed mechanism of claim 1 wherein at least about ten support bars are aligned transversely on the tufting machine.

7. The yarn feed mechanism of claim 1 wherein the yarn feed roll can be rotated at any one of at least twenty speeds by communication with the servo motor.

8. The yarn feed mechanism of claim 1 wherein the yarn feed rolls in communication with each servo motor have a portion mounted concentrically about and connected directly to the servo motor.

9. The yarn feed mechanism of claim 8 wherein the yarn feed rolls have a yarn feeding surface portion having a smaller diameter than the portion mounted concentrically about the servo motor.

10. The yarn feed mechanism of claim 1 wherein each servo motor communicates with the yarn feed roll by driving a gear of relatively small diameter which communicates with a gear of relatively large diameter on the yarn feed roll.

11. The yarn feed mechanism of claim 10 wherein the torque of each servo motor is less than the torque of the yarn feed roll that the servo motor communicates with.

12. The yarn feed mechanism of claim 10 wherein each of the servo motors operate with less than ten pounds per inch of torque.

13. The yarn guide mechanism of claim 1 having a plurality of yarn guide plates with apertures arranged in offset parallel rows.

2. The yarn feed mechanism of claim 2 wherein said yarn feed mechanism comprises approximately twenty servo motors and associated yarn feed rolls attached to said support bar.

14. A method of tufting a carpet by feeding a backing fabric through a tufting machine of the type having a plurality of spaced needles aligned to form a row transverse to the machine for reciprocal movement through the backing fabric, a yarn supply, and a yarn feed mechanism having between about one-half and one-fifth as many independently controlled servo motors as there are needles in the transverse row comprising the steps of:

(a) feeding yarns from the yarn supply to the yarn feed mechanism;

(b) placing a group of at least two yarns in contact with a yarn feed roll in communication with an independently controlled servo motor;

(c) feeding the group of yarns out of the yarn feed mechanism and threading each yarn in the group through an adjacent needle in the transverse row;

(d) placing additional groups of at least two yarns on additional yarn feed rolls in communication with independently controlled servo motors and threading each yarn in each group to adjacent needles in the transverse row until the transverse width of threaded needles approaches the width of the backing fabric;

(e) feeding the backing fabric through the tufting machine while reciprocating the transverse row of needles, and operating the servo motors to feed yarn to the needles according to a predetermined pattern.

15. The method of claim 14 wherein the torque applied by the yarn feed rolls to the groups of contacting yarns is greater than the torque applied by the servo motors to the yarn feed rolls.

16. The method of claim 14 wherein each group of yarns consists of two yarns.

17. The method claim 14 wherein the independently controlled servo motors are aligned in rows of at least five motors extending longitudinally from the tufting machine parallel to the direction of the feed of the backing fabric.

18. The method of claim 17 in which each row of independently controlled servo motors is attached to a mounting surface of a support bar and a controller electronically receives information corresponding to the reciprocating position of the transverse needle row and electronically sends corresponding ratiometric pattern information to the servo motors.

19. The method of claim 14 wherein each group of yarns is threaded through a yarn guide prior to contacting the yarn feed roll.

20. The method of claim 14 wherein each group of yarns is threaded from the yarn feed roll to the needles without employing a tube bank to guide the yarns.