US30725A - Friction-brake foe bobbins - Google Patents

Description

UNITED STATES PATENT OFFICE.

TRUMAN ESTES, OF NORTH BENNINGTON, VERMONT.

FRICTION-BRAKE FOR BOBBINS.

Specification of Letters Patent No. 30,725, dated November 27, 1860.

To all whom it may concern:

Be it known that I, TR'UMAN ESTES, of North Bennington, in the county of Bennington and State of Vermont, have invented certain new and useful Improvements in a Self Adjusting and Regulating Brake to be applied to Bobbins; and I do hereby declare the following to be a full, clear, and exact description of the construe tion and operation of the same, reference being had to the accompanying drawings, making a part of this specification, in which- Figure l, represents in perspective a bob bin with the self regulating brake applied to it. Fig. 2, represents a vertical cross sec tion through the bobbin and brake. Fig. 3, represents a perspective View of the brake detached from the bobbin frame.

Similar letters of reference where they occur in the separate drawings denote like parts in all the figures.

In unwinding thread or yarns from a series of bobbins, itis next to impossible to always keep the bobbins of uniform size, and when not so kept, the tension upon each and every thread drawn from them varies, in exactproportion to the varying of the power required to turn the bobbins-and when the series of threads are gathered together to be put into twine, cordage, or other fabric, it is found that the uneven tension upon them, makes knotty and irregular work. Besides, it is not so strong, as the threads most strained in unwinding must stand the whole strain upon the cord or other fabric, before it reaches those most slack, or in other words the strained strands must break before the weight can come upon the unstrained ones. Spring brakes are out of the question, as they are constantly varying and are not controlled by the power re quired to turn the bobbin at all times. Turning the bobbins by machinery that is variable, will not accomplish the end aimed atwthe compensation must be made by the thread or yarn upon the bobbin, uncontrolled by any other mechanism.

Vhen a bobbin is full, it, of course unwinds or turns much more easily than when nearly empty, and between these two points of full and empty, the power required to turn the bobbin is constantly varying.

My object is to provide some pressure that will vary precisely with the varying of the power required to turn `the bobbin, and this I have done by a very simple, but reliable mechanism. f

My invention consists in applying to the yarn or thread on the bobbin, an overbalanced friction plate or arm, so arranged as to apply its greatest pressure against the thread when the bobbin is full, and its least pressure against the thread when the bobbin is nearly or quite empty, and that varies gradually between these two points just as the power required to turn the bobbin increases, as will be hereafter explained.

To enable others skilled in the art to make and use my invention, I will proceed t0 describe the same wit-h reference to the drawings.

A, represents a portion of a bobbin frame, showing a bobbin B, hung therein, in any of the usual well known ways so as to freely turn on its supports.

C, is the self regulating friction brake. This friction brake, as more clearly shown in Fig. 3, is made of cast or wrought metal or parts of each, for cheapness and durability, but may be made of other material. The rear portion a (that is to say the portion behind its journals or supports b, b) overbalances the forward portion c, so as to keep the forward portion c, constantly against the yarn on the bobbin, and over suiiicient surface of the thread or yarn, as not to drop into slight depressions, and be influenced by them, instead of the general surface of the yarn. This forward part of the brake, may be slightly curved as shown, and if found desirable may be made of glass, bone, wood, or any other material than metal--the rear portion a on account of the weight is better of metal. And to prevent the brake from tipping over when an empty bobbin is taken out and a full one put in, a stop CZ may be arranged to catch the rear of the brake.

Suppose the bobbin to be full-the brake will then be in the position shown in Fig. 1 and the thread or yarn will be drawn from the top of the bobbin as shown by the red line e. In this position of course the bobbin is most easily turned as the leverage from e, to the center of the bobbin is the greatest. In this position too the overpoise, or heavy part a of the brake is nearest to a horizontal plane, and most remote from its fulcrum b, b, consequently is applying its greatest force upon the arm or plate c. Now as the yarn is unwound, the overpoise or heavy part a of the brake moves in the arc of a circle drawn from the point Y), just as the arm or plate c, moves toward the center of the bobbin, until When the part c, arrives Where it is shown in dotted lines the overpoise Will be, nearer to the fulcrum b, in a vertical line, and thus have less power upon the part c, and make less pressure on the yarn, so that What is lost by leverage When the yarn gets down to f, is compensated for by the lesser pressure of the arm c, When it arrives at the position represented by dotted lines. If the part a hung immediately beloW the fulcrum journals b of course it Would exert no influence on c at all but just in proportion as the part a falls from a horizontal to a vertical line, in the same proportion does it diminish its force upon c until it runs entirely out when in a vertical position. Y

It is the application of the Roman balance to the unWinding of bobbins7 and Works as mathematically correct in applying variable friction to bobbins, as the Roman balance does in connection With the regulation of steam. It is probably the most simple and yet the most perfect compensation for the varying leverage of yarn as it is unwound from a bobbin j that has been discovered. In practice it is perfect, in giving uniform tension to any number of threads Wound from bobbins of varying diameters, and as such is highly valuable.

Having thus'fully described the nature and object of my invention What I claim therein as new and desire to secure by Letters YPatent is A self adjusting or regulating brake C, constructed and operating substantially as herein described and represented, for giving an equal and proper tension to threads or yarns that are being drawn olf.

TRUMAN ESTES.

Witnesses:

J. ESSEX, D. W. C. FAY.

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