Winding – tensioning – or guiding – Strand tensioning device – Tortuous course
Patent
1999-02-01
2000-10-24
Walsh, Donald P.
Winding, tensioning, or guiding
Strand tensioning device
Tortuous course
B65H 5912
Patent
active
061353779
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to a yarn brake for use in weaving machines.
A yarn brake--as known from EP-A-326784 by Loepfe--comprises, in addition to the two fixed yarn guide elements, a swiveling bridge supporting two further yarn guide elements, aligned with the straight yarn path in the starting position of four rod-shaped braking elements. A certain distance is set between the rotation axis of the braking elements and the straight yarn path. The bridge rotates about a further rotation axis, essentially parallel to and spaced from the straight yarn path. The bridge is resiliently biased against the braking elements, in its swiveling direction, by repelling magnets positioned into the frame. As the brake is operated, the braking elements are caused to perform an angular movement about their rotation axis from the starting position, laterally across the straight yarn path, into the braking position on the other side of said path. Due to the tension produced in the yarn, deviated by the braking elements and by the fixed yarn guide elements, the bridge yields with a certain stroke against the force of the repelling magnets. The adjustment device allows to vary the position of the repelling magnets inside the frame, so as to vary the counter-force of the bridge and to thereby vary the degree of yarn deviation and the braking force acting on the moving yarn.
Another yarn brake--as known from EP-A-527510 by Picanol--provides for the rotation axis of the two rod-shaped braking elements to be positioned perpendicularly to the straight yarn path and to intersect said path. Both braking elements are positioned on a rotatable disk controlled by a rotation drive. The angular stroke of the braking elements about the rotation axis is limited by taps supported by the frame. The angular position of the taps is adjustable about the rotation axis of the braking elements through a set of screws engaging into a ring supporting the taps inside the frame. Adjusting the angular position of the taps requires a change in the angular stroke of the rotatable disk and of the rotation drive.
A similar yarn brake--known from U.S. Pat. No. 3,406,832 by Rempei--is provided with two spaced apart stop devices of the frame, which interfere with the oscillating path of a lever projecting sideways from the rotatable body carrying the braking elements. Two cables, fixed to opposite sides of the lever, are connected with drawing magnets operating the rotatable body in both rotating directions. The stop devices of the frame are thus apt to reduce the maximum angular stroke of the rotatable body. It is possible to vary the degree of yarn deviation in the braking position of the braking elements by adjusting the stroke of the drawing magnets.
SUMMARY OF THE INVENTION
The object of the present invention is to supply a yarn brake that easily, but efficiently, varies the degree of yarn deviation in the braking position of the braking element with a simple structural design of the yarn brake.
Any variation of the distance between the rotation axis of the braking element and the straight yarn path is apt to vary the degree of yarn deviation in the braking position of said braking element. This can be obtained, either by moving said rotation axis closer to the straight yarn path or even further from said path, or by moving the straight yarn path closer to or further from said rotation axis, or finally, by reciprocally shifting both the rotation axis and the straight yarn path. It is anyhow appropriate to merely shift the rotation axis in respect of the straight yarn path, as the yarn brake is usually mounted in a predetermined position (defined by fixed yarn guide elements of the frame) in respect of the straight yarn path, aligned with adjacent structural components forming part of yarn processing system, for example a weft yarn feeder and the weft yarn insertion means of a loom.
In a further embodiment, the adjustment device shift the rotation axis of the braking element in respect of the straight yarn path.
Another
REFERENCES:
patent: 1605842 (1926-11-01), Jones
patent: 2202323 (1940-05-01), Sullivan
patent: 2571678 (1951-10-01), Burns
patent: 2618445 (1952-11-01), Buder
patent: 2899221 (1959-08-01), Pieper
patent: 2932151 (1960-04-01), Heffelfinger et al.
patent: 2949253 (1960-08-01), Stoddard et al.
patent: 3258214 (1966-06-01), Comstock
patent: 3559916 (1971-02-01), Hilscher
patent: 5163594 (1992-11-01), Meyer
patent: 5226459 (1993-07-01), De Ro et al.
patent: 5368244 (1994-11-01), Melillo et al.
patent: 5791541 (1998-08-01), Jitsuishi et al.
Covelli Marco
Gabogna Giorgio
Nouva Roj Electrotex S.r.l.
Walsh Donald P.
Webb Collin A.
LandOfFree
Yarn brake for looms does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Yarn brake for looms, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Yarn brake for looms will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1955523