US246591A - Tension and take-up device for sewing-machines - Google Patents

Description

(No Model.) 2 Sheets-Sheet 1.

J. W. BLODGETT. TENSION AND TAKE-UP DEVICE FOR SEWING MACHINES.

No. 246,591. Patented Sept. 6,1881.

(No Model.) 2 Sheets --Sheet 2. J. W. BLODGETT.

TENSIONAND TAKE-UP DEVICE FOR SEWING MACHINES.

No. 246,591. Patented Sept. 6,- 1881.

Wiifiesgesk- Invent 0T.

UNiTED STATES PATENT OFFICE.

JOHN W. BLODGETT, OF CHICAGO, ILLINOIS.

TENSION AND TAKE-UP DEVICE FOR SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 246,591, dated September 6, 1881.

Application filed March 19, 1881. (No model.)

To all whom it may concern:

Be it known that I, JOHN W. BLODGETT, residing at Chicago, in the county of Cook and State of Illinois, and a citizen of the United States, have invented new anduseful Improvements in Tension and Take-Up Devices for Sewing-Machines, of which the following is a full description, reference being bad to the accompanying drawings, in which Figure 1 is a side elevation of a sewing-machine embodying my invention; Fig. 2, a top or plan view of the arm of the same; Figs. 3, 4, and 5, details of the take-up device; Figs. 6 and 7, details of the socket or collar by means of which the tension arm or spring is held in position and its pressure regulated.

A proper tension on the thread and the taking up of the slack thread constitute two of the essential featuresin the successful working of a sewing-machine, and in practice it has been found that the tension should be one that can be regulated or changed so as to adapt it to ditl'erent conditions and requirements of the work and to the amount and quality of the thread, and that the takeup should be automatic in its operation, and perform its work so as to prevent any tangling or knotting of the thread, and at the same time be adjustable so as to accommodate itself to the amount of the slack in the thread.

To construct devices that will accomplish these desired ends successfully and perform their respective works in an efficient and reliable manner, and so as not to injure and break the thread or interfere with the operation of the machine, and which can be easily and quickly changed or regulated so as to adapt them to the varying conditions and requirements of the work and the thread, is the ob- 0 ject of this invention; and it consists in providing a spring or spring-arm, secured at one end to a collar or socket, which can be raised or lowered on its spindle or arbor and be ro- --tated thereon, so as to cause the free end of provided with an adjustable set-collar located on the tube or casing for limiting the action of the spring and causing its movement to correspond to the amount of slack in the thread.

1n the drawings, A represents the tension arm, made of spring-steel or other suitable material, and of the requisite flexibility, so that when its f1 ee end is hearing on the spool or thread it will exert the necessary pressure to prevent the thread from bein g unwound, except as required for use.

B is a set-collar or socket having a central circular opening adapted to receive an arbor or spindle, to which the collar or socket can be firmly secured and held in any desired position by means ofa set-screw, b, or other suitable device, so thatit can be raised or lowered to bring it in the proper position for support ing the spring A properly. In this socket or collar B is a transverse slot or opening, a, to

receive the end of the tension-arm A, and by turning the socket or collar on its arbor or spindle the angle at which this slot to stands in reference to a straightline parallel with the arbors or spindles for the spool and the socket B can be made greater orless, so as to cause the free end of thetension-arm A to bear with a greater or less force on the thread, and thereby vary the amount or degree of tension.

0 is a spindle or arbor for the socket or collar B. Its lower end is firmly secured, in the form of construction shown, to the ordinary arm, I, ofthe machine which supports the head H for the presser-ioot and needle-bars Grand H.

D is an ordinary spool for thread.

E is a spindle or arbor for the spool. Its lower end, as shown, is firmly secured to the sewing-machine arm forward of the spindle or arbor O, and its diameter is such as to allow the spool to be placed thereon and rotate free- 1y. The position and location of the spindles or arbors on the machine may be varied to adapt them to machines of different constructions and bring the tension device and spool in the proper relation to each other.

By means of the spring or spring-arm A and the adj ustable and rotating socket or 001- lar B it will, be seen that any desired tension can be given by simply turning the socket or collar on its arbor, so as to cause the free end of the spring-arm or tension-arm to bear with IOC more or less force, and that all that is necessary to be done in order to produce this result is to loosen the set-screw ot' the collar, turn the collar in the required direction, and then tighten the set-screw. To increase the tension the socket or collar B is turned so as tocause the end ofthe slot or opening a which is toward the spool to be carried inward or toward a line drawn through the centers of the arbors G and D. To decreasethe tension a reverse movement is given to the socket or collar B. By thus changing the line of direction of the slot a any required degree of tension can be applied to the thread.

Fis a casing or tube, secured atits lower end to the upper end of the needle-bar G so as to move therewith, and having its upper end left open so as to permit of the insertion of a coilspring, d. ()n opposite sides of this casing or tube F and in line with each other are slits c, to permit of the passage of the thread transversely through the tube or casing and over the upper end ofthecoil-spring d,- and in order to support the thread properly a cap, 0, having an extension, 0, which fits the interior of the spring is provided, on which cap 6 the thread rests, and, as shown, the cap is prevented from being thrown out bythe recoil of the spring by a set-screw, h, or in any other suitable manner. Around the casing or tube F is located an adjustable set-collar, j", which can be adjusted up or down on the tube, and when in the desired position can be held therein by a set-screw, g, or other suitable device. This set-collarflimits the descending movement of the coilspring by reason of the thread coming in contact there with, so as to have the descent of the spring correspond to the slack in the thread.

The operation will be readily understood. The thread, passing over the coil-spring, as it is drawn by the descent of the needle will cause the coil spring to contract to the same extent, and as the needle ascends the spring will return to its normal condition, and will, of course, take up any slack there may be in the thread, and by means of the set-collar the contraction of the spring can be made to correspond with the descent of the needle, and the recoil of the spring will be to the same extent.

By means of this device the slack thread will all be taken up in an etficient manner, and the tension-arm prevents any unwinding of the thread from the spool, except as required, so

that kinking and knotting of the thread will not take place, and no interference will arise with the operation of the machine.

In Fig. 1 a button-hole attachment is shown, but as the same is made the subjectmatter of another application of even date herewith it need not here be described.

I do not claim a flat spring arranged to press upon the spool of thread and having its tension adjusted by a set-screw bearing against the spring between its point of attachment to the machine and the spool of thread; neither do I broadly claim a sliding cap arranged on the needle-bar and supported by a coiled spring, the cap having an eye through which the thread passes on its way to the needle.

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

1. In a tension device for sewing-machines, the combination ot' the fixed cylindrical arbor O, the collar 15, provided with the transverse slot a and set-screw Zr, and arranged to be rotated and adjusted vertically on the spindle to change the position or angle of the slot, and the flat spring A, having one end secured in the transverse slot and its free end arranged to bear on the spool. of thread, substantially as described, whereby the pressure of the spring on the spool can be adjusted by turning the slotted collar on its axis, all as and for the purpose described.

2. The tube F, secured to the needle-bar and provided with two coincident vertical slots, 0, extending to the upper end of said tube, in combination with a coiled spring, at, arranged within the tube, and the thread-rest bearing on the spring and closely fitting and sliding within the slotted tube, all substantially as and for the purpose described.

3. The tube F, secured to the needle-bar and having the two vertical coincident slots 00,

the coil-spring d, arranged within the tube, the

cap piece a, closely fitting and sliding within the tube, and the collar f, arranged to slide upon the exteriorofthe tube, and provided with a setscrew, g, for adjusting and locking the collar in position to regulate the descent of the coil-spring, all substantially as and for the purpose described.

JOHN W. BLODGETT.

W'itnesses:

O. W. BOND, 13. A. PRICE.

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