Textiles: knitting – Feeding – Positive
Reexamination Certificate
2000-05-24
2001-03-20
Worrell, Danny (Department: 3741)
Textiles: knitting
Feeding
Positive
C066S12500A, C066S146000
Reexamination Certificate
active
06202450
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a yarn delivery method, and more particularly to a uniform yarn delivery method and apparatus for a circular knitting machine.
2. Description of Related Art
Fabric consists of many loops (i.e., warp and weft). A uniform loop is key to a high quality fabric. Further, the uniform loop is determined by a good knitting process. As such, a stable and uniform yarn delivery is an object to be achieved by fabric manufacturers.
Conventionally, yarn supply device is for providing a stable and uniform yarn delivery. In comparing a simple yarn supply drum with a storing drum, the latter has a better yarn delivery capability. However, the storing drum may suffer at least one of the problems such as yarn winded on drum not uniformly delivered toward the lower position, loops entangled, and dislocation of loops. Further, the yarn tension detection arm of the storing drum presses on yarn by its weight only. The yarn tension detection arm is stopped immediately after yarn tension disappears. However, this technique is outdated because 1) it cannot accommodate high speed knitting requirements today, and 2) the yarn tension detection arm is not sufficiently sensitive. As such, fabric knitted by a knitting machine equipped with such a storing drum is poor in quality. Thus it is not acceptable by the fabric manufacturing art.
In a typical yarn delivery technique, tension of yarn is related to cam position of the knitting machine. Conventionally, yarn is made as taut as possible before entering the knitting machine so as to enhance yarn tension, thereby obtaining loops with uniform tension and identical size. However, it is impossible to visually determine the uniformity of yarn tension because, as stated above, the yarn tension detection arm is activated by its weight (i.e., non-adjustable) and yarn is too taut. In fact, the cam position usually is adjusted by an experienced operator. The operator often adjusts the yarn tension to its maximum. As a result, fabric quality is poor as manufactured by high speed knitting machines. Further, a variety of disadvantages such as short pitch, small loop, breakage, dislocation, rough, poor quality, low elasticity, and high contraction are experienced.
SUMMARY OF THE INVENTION
It is thus an object of the present invention to provide a uniform yarn delivery method and apparatus for a knitting machine for eliminating the above drawbacks of prior art.
It is another object of the present invention to provide a uniform yarn delivery method and apparatus for a knitting machine for obtaining a uniform, smooth, glossy, and high quality fabric.
It is still another object of the present invention to provide a uniform yarn delivery method and apparatus for a knitting machine wherein the loop length per delivery is maximum, loops are uniform and identical, and fabric has the advantages of smoothness, high elasticity, and low contraction.
It is a further object of the present invention to provide a uniform yarn delivery method and apparatus for a knitting machine wherein the knitting machine is of high efficiency and highly utilized. Further, yield is sufficiently high and the knitting machine has a low wear-out, thereby reducing the manufacturing cost.
To achieve the above and other objects, the present invention provides a uniform yarn delivery method comprising the steps of: (1) sending yarn derived from a supply cone to be guided tangentially on a yarn supply drum so as to tighten yarn thereon; (2) suitably slackening the taut yarn sent from yarn supply drum prior to sending to a yarn tension detection arm; (3) the yarn tension detection arm elastically vibrating the yarn; and (4) adjusting the cam position associated with the yarn tension detection arm so as to cause yarn to enter into the knitting machine for knitting under the same vibration of the yarn tension detection arm. With this, all yarn sections are the same in length, loops are identical, and fabric has a uniform texture.
To achieve the above and other objects, the present invention provides a uniform yarn delivery apparatus comprising a yarn supply drum, a yarn tension detection arm, a lead-in yarn eye, an outgoing yarn stop-motion device, and a hook wherein at least one winding of yarn is stored on the circumference of a yarn supply drum, a yarn brake of the outgoing yarn stop-motion device has a spring for adjusting the vibration of yarn so as to function in cooperation with the position of cam to adjust yarn, thereby preliminarily tightening yarn prior to sending to the yarn supply drum, and the yarn tension detection arm elastically vibrates the yarn. With this, yarn sections are the same in length, loops are identical, and fabric has a uniform texture.
The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings.
REFERENCES:
patent: 6105398 (2000-08-01), Leins et al.
patent: 2661924 (1991-11-01), None
patent: 1326672 (1937-07-01), None
Ware Fressola Van der Sluys & Adolphson LLP
Worrell Danny
LandOfFree
Uniform yarn delivery method and apparatus for knitting machine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Uniform yarn delivery method and apparatus for knitting machine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Uniform yarn delivery method and apparatus for knitting machine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2486335