THREAD TENSION REGULATORS

or

THREAD CONTROLLERS

 

One of the earliest difficulties encountered by the maker of a sewing machine was that of effectually controlling the loose thread after it had been cast off the shuttle. In some machines this slack thread amounts to six, in others to one or two, inches. Howe got over the difficulty by passing his thread, on its way to the needle, over the upper extremity of the needle bar, the ascent of the bar then sufficed to pull up the slack (*). Singer improved upon this by furnishing his machine with a spring take-up lever, partially controlled by the needle bar. Wilson, in the Wheeler & Wilson machine, had neither of those arrangements, but depended upon the succeeding revolution of the hook to draw up the slack of the preceding stitch.

(*) Note:

Howe's machine introduced for the first time a distinct take up. (read it here)

These devices were all far from perfect in their operation, chiefly because they commenced to act too soon. In each case the pulling up commenced with the rise of the needle and the tightening operation subjected the thread to all the friction of rubbing its way through both needle-eye and fabric. Now, an ideal take-up should not commence to act until the needle has ascended above the fabric and one of the most important steps towards perfection in sewing machines was undoubtedly attained when such a device was actually invented. In effecting this the means employed consisted of a differential or variable cam, rotating with the main shaft. This controlled the movements of a lever called the take-up, pivoted to the machine (Fig. 4).

 

Not only has it been possible by these means to control the tightening of the stitch, but the paying out of the thread for enveloping the shuttle also and both the paying out and pulling up are actually effected after the needle has ascended above the cloth. The introduction of the positive take-up, the first forms of which appeared in 1872, not only simplifies the movements of the shuttle or hook, but for the first time renders the making of the lock-stitch possible, while the needle has a direct up and down-motion. Thus we find that in most of the swiftest sewing machines the needle-bar is actuated by a simple crank-pin, or eccentric, there being no loop-dip or pause in its motion. The diagram shows the positive take-up in three positions; at the commencement of the needle's descent, during the detention of the loop by the beak and during the casting off of the loop. The dotted lines indicate the path of the cam to produce these positions. The intermittent movements of the take-up have thus led to the abandonment of variable motions in both needle and shuttle and particularly so in oscillating shuttle machines.

 

Recent Advances in Sewing Machinery

by John W. Urquhart - 1887

 

 

 

US PATENTS

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US 35.126                                  E. L.  Pratt

Thread Tension of Sewing Machines

Assignor to John B. Collins

My invention consists in so combining and arranging the tension devices which operate upon the separate threads used in a sewing mechanism forming the double chain or the Grover & Baker stitch that a relative proportion, or any desired relative proportion, of tension between the two threads operates automatically upon each thread and is maintained operating thereupon in the same proportio without being disturbed when the total amount of pressure or tension on the threads is in creased or diminished. I claim:

So combining and arranging the tension devices which operate upon the threads used in a sewing machine which makes the double chain or Grover & Baker stitch that a relative or any desired relative proportion of the whole tension upon the threads is made to be automatically operative upon each thread and so maintained when the total tension on the threads is increased or diminished, said arrangement and combination being such that changes in the amount of the tension may be made with facility, substantially as described

April 29, 1862

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US 35.542                               Paul  Pryibil

Tension Regulator for Sewing Machines

The object of this invention is to increase the tension of the needle-thread of a sewing machine in the same measure as the diameter of the bobbin in the shuttle decreases and consequently the tension of the shuttle-thread increases.

What I claim as new and desire to secure by Letters Patent, is:

1. The arrangement of the friction-pulley O , with the conical hub E, in combination with the screw-spindle G and spring-pad F, constructed and operating substantially as and for the purpose specified.

2. The arrangement of the elliptical nut d on the spring H, in combination with the screw. spindle G and pulley D, substantially as and for the purpose described.

3. The recess e and shoulder f on the screw. spindle G, in combination with the lower part, g, of the nut d, as and for the purpose set forth. 

June 10, 1862

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US 175.463                          James  A.  House

Take-up for Sewing Machine

My invention more especially relates to sewing machines of the Wheeler & Wilson type, particularly adapted for sewing leather and heavy fabrics and constitutes an improvement on the machine shown and described in Letters Patent US 124.360 dated March 5, 1872 and Letters Patent US 145.570  dated December 16, 1873. I claim as of my own invention:

1. The combination, substantially as here in before set forth, of the driving-shaft revolving with a uniform speed, the hook revolving at a variable speed relatively thereto, the driving-can, its pitman-connection and the needle-lever, with its short arm forming an offset from the long arm and occupying a different vertical plane from that passing longitudinally through the driving-shaft, whereby a space is left between the needle-lever and the bracket-arm for the play of the take-up lever and a longer pause is given to the needle at the end of its upward stroke than at the end of the down-stroke, for the purposes: set forth.

2. The combination, substantially as here in before set forth of the driving-shaft revolving with a uniform speed, the hook revolving at a variable speed relatively thereto, the needle-lever, with its short arm forming an offset from the long arm and occupying a different vertical plane from that passing longitudinally through the driving-shaft, the grooved cam on the driving shaft and the take-up lever vibrated thereby, whereby the take-up may be located between the needle lever and bracket-arm and complete the stitch during the elevation of the needle. 

Assignor to The Wheeler & Wilson Manufacturing Company

March 28, 1876

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US 177.038                        Ausbert  H.  Wagner

Take-up for Sewing Machine

My invention is designed to increase the simplicity, durability and ease of operation of a shuttle sewing machine and it consists, principally, in the construction and operation of the take-up, substantially as and for the purpose hereinafter shown. What I claim as new is:

1. The take-up spring W w, constructed as shown and arranged within the head B', in combination with the studd, which bears upon its rear inclined side and operates to with draw the slack of the upper thread within said head, substantially as and for the purpose shown.

2. In combination with the lever Q, the ball and socket bearings P and Q', respectively, Substantially as and for the purpose specified.

3. In combination with the shaft I, the fixed boxes K and K, provided each with jawski k and the detachable boxes K and K, fitted within said jaws and secured in place by means of the pinsk and k, substantially as and for the purpose set forth.

4. In combination with the presser-bar C, working longitudinally within the vertical slot b of the housing B, the screw F, passing downward through a threaded opening in said housing and the spiral spring E, attached at its upper end to said presser-bar and at its lower end to the lower end of said screw, substantially as and for the purpose shown and described.

May 2, 1876

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US 183.678                          James  Jamieson

Take-up for  Sewing Machine

Assignor to Richard Mott Wanzer

This invention relates to an improved take up for sewing machines, its object being to dispense with the ordinary wire take-up devices, as heretofore constructed, which are operated entirely by the upward and down ward motion of the needle-bar in conjunction with springs and provide a take-up that is operated partially by a calm on the driving shaft of the needle-bar and partially by the motion of the needle-bar, whereby a more simple and effective take-up device is obtained. What I claim and desire to secure by Letters Patent, is:

In combination with the take-up J, the cam E and slotted needle-bar G, the several parts being arranged as described, whereby the proper motion is imparted to the take-up, as and for the purpose set forth.

October 24, 1876

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US 201.260                          John  McCloskey

Take-ups for Sewing Machine

My invention is more especially designed as an improvement on the well-known. Wheeler & Wilson old-style sewing-machines, in which the stitches drawn tight and completed by the rotating hook at the same time that the next stitch is in course of formation, the slack thread that has to be taken up to complete the stitch being detained below the cloth-plate by a brush or pad until the rotating hook can act upon it. My invention may, however, be adapted, to a greater or less extent, to other sewing machines, shuttle as well as hook machines and may be used with straight needles and needle bars, or with vibratory arms and curved needles, as specially shown and described herein after. The object of my invention is mainly to take up and complete each stitch without drawing the needle-thread back through the eye of the needle, thereby obviating the friction and wear upon the thread from its alternate to-and-fro movement through the eye of the needle in passing out to a sufficient extent for the shuttle or bobbin, as the case may be, to pass through its loop and then back and up to complete and tighten the stitch. Its object is, further, with reference to the Wheeler & Wilson sewing machine first above mentioned and other similar machines, to dispense with the pad or brush before mentioned and thereby avoid the friction of the same upon the rotating hook, with the consequent heating of the latter and adjacent parts, resulting at times in so much expansion of the metal parts in contact as to cause imperfect working of the machine; its object being also to tighten the stitch in one direction only at a time and not in two directly-opposite directions, as is the case with the pad or brush machines just mentioned, which unfits them for stitching through heavy fabrics, owing to the great friction of the thread in the fabric. 

March 12, 1878

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US 206.774                        Nathaniel  A.  Conklin

Automatic Thread-Tension for Sewing Machine

The object of my inventionis to provide for furnishing a sewing machine at the time of making each stitch and in a simple and inexpensive manner, with the exact quantity of thread required to form a stitch. To this end the invention consists in the combination, with the means for operating the needle, of a tension device, whereby the thread required to form a stitch is caused to be drawn out on the descent of the needle-bar and one portion of the thread is caused, directly or in directly, to bind and hold another part, so as to obstruct the drawing of thread from the spool save at the proper time. What I claim as my invention and desire to secure by Letters Patent, is:

1. In a sewing machine, the combination, with the means for operating the needle, of a tension device, whereby at certain times during the operation of the needle one portion of the thread used in sewing is caused, directly or indirectly, to bind or act as a brake on all other portion, substantially as and for the purpose specified.

2. In a sewing machine, the combination, with a vibrating needle-arm, provided with an eye for the reception of the thread used in sewing, of a fixed arm extending from the frame of the machine and provided with two eyes for the reception of the said thread, whereby during the operation of the machine one portion of the thread is caused to directly bind or act as a brake on another portion, substantially as and for the purpose specified.

August 6, 1878

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