US894375A - Take-up mechanism for sewing-machines. - Google Patents

Description

PATENTED JULY 28, 1908.

J. B/FARR. TAKE-UP MECHANISM FOR SEWING MAGHI NBS.

APPLICATION FILED AUG. 31, 1906.

WITNESSES:

INVENTOR JOHN B. FARR, OF INDEPENDENCE, MISSOURI.

TAKE-UP MECHANISM FOR SEWING-MACHINES.

Specification of Letters Patent.

Application filed August 31, 1906.

Patented July 28, 1908.

Serial No. 332,818.

T 0 all whom it may concern:

Be it known that I, JOHN B. FARR, a citizen of the United States of America, residing at Independence, in the county of Jackson and State of Missouri, have invented certain new and useful Improvements in Take-Up Mechanism for Sewing-Machines; and I dohereby declare that the following is a-full, clear, and exact descri tion of the invention, such as will enable ot ers to make and use the same,'reference being had to the accompanying drawing, formlng a part of this specification.

The object of the invention is firstto minimize the draw upon the thread of the loop during the passage of the shuttle through the loop. Secondto enable the needle bar to draw more thread than it would by the length of its stroke. Thirdto increase the drawing energy upon the thread of the loop in the up stroke of the needle bar.

The invention consists in the novel construction and combination of parts such as will be first fully described and then specifically pointed out in the claims.

In the drawings Figure 1 is a front view of the face or covering plate to the vertical casing on the arm of a sewing machine showing the needle bar within the box, and needle, the presser foot and bar, and the invention applied to the face plate. Fig. 2 is a vertical sectional view of the casing or boxand face plate and a portion of the arm supporting the box showing the needle bar, and needle, and a portion of the rotary shaft and cam actuating the needle bar, taken at right an les to and upon line r a: of Fig. 1, showing t e invention. Fig. 3 is a detail sectional view of a ortion of the face plate showing the upper fu crumed end of the take 11 lever arm, the coiled spring connected wit the arm near the inner surface of the face plate, the bearing extending through the face plate and the arm upon the bearing connected with the spring and the regulating arm upon the outer end of the bearing and face plate and the projection on the arm engaging with the rack. Fig. 4 is a detail broken view of the inner surface of the face plate showing the slots in the face plate for the passage of the thread and increasing the length of the loop and the s ring controlled lever arm. Fig. 5 is front view of the face plate on the box -or casing on the arm in a modified form, showing the needle bar and needle and presser foot as in Fig. 1 and a portion of the lever arm upon the outer surface of the face plate. Fig. 6 is a vertical sectional view of the portion of the supporting arm and box and needle bar and the rotary shaft as in Fig. 1, showing the front plate as in Fig. 5 in vertical section taken upon the line y y, showing the modified take u devices. Fig. 7 is a detail broken view 0 the needle bar showing the forked pin and a portion of the front plate as in Fig. 5 showing the forked thread parrier and the position of the thread in the Similar numerals of reference indicate corresponding parts in all the figures of the drawing.

Referring to the drawing 10 indicates a portion of the hollow arm which extends horizontally and is formed integral with the standard on the base plate of a sewing machine and within which arm is j ournaled the rotary power shaft 1 2, actuating the needle bar 14. Upon the forward end of the arm 10 is the ordinary vertical box or casing 15, through the upper and lower end portions of which box extends the reciprocating needle bar 1 1, and upon'which bar is the ordinary adjustable cam plate 16, hcving the groove 17, within which groove extends the antifriction pin or lug 18 in the crank arm 18 on the shaft 12. 19 indicates the needle on the needle bar and 20 indicates the presser foot rod, 21 the presser foot and 22 the lifting lever commonly used upon sewing machines. 23 indicates the face plate to the box or casing 15 on the arm 10, which is removably secured to said casing by the screws 24, and in which plate opposite the needle bar is a vertical slot 25. Upon the forward surface of the needle bar is rigidly connected a thread carrying pin 26, the outer end of which pin extends through the slot 25, and to a position a slight distance beyond the outer surface of said plate and is bent at right angles at 27, and extended a short distance upwardly and at an angle to the needle bar.

In the face plate 23 and the portion of said plate traversed by the outwardly inclined thread carrier 27 on the needle bar is a vertical slot 30, extending from the upper end of said face plate 23 downwardly and nearly to the tension plates 31, located. a short distance upwardly from the lower end of the face plate, the lower end of the slot being curved inwardly at 30 in a slight degree. The tension plates 31 consist of two concave disks mounted on a threaded stud 32 upon which stud is an adjusting nut 33, which bears upon the outer disk, between which nuts and disks is a spiral spring forming a tension device of the well known description. In the portion of the face plate 23 on the other side of a vertical line extending through the guide slot '25 and at a point about one third the distance from said line to the outer vertical surface of the face plate is a guide slot 34, which extends from the upper end of the face plate downwardly to a point 34 a slight distance below a horizontal. line drawn through the upper end of the slot 25 in the face plate from which point the slot extends downwardly and is inclined inwardly in the direction of slot 25 and terminates near the lower end of said slot. The upper end of the portion of the face plate intermediate slots and 34 is extended upwardly a slight distance and curved in the arc of a circle as at 35.

36 indicates the take up lever or arm which consists of a short length of wire upon the inner surface of the face plate 23 which is bent at 36 at a point a short distance below a horizontal line extending through the upper end of slot 25 and operative upon one side of a vertical line extending through said slot and reversely to the direction of inclination of the portion 27 of the thread carrying pin 26, the lower end of the wire extending downwardly a slight distance below a line horizontally extended through the lower end of the slot 25, said lower end of the wire being bent at 37 in an outwardly curved line.

The upper end of the wire or arm 36 extends upwardly to a position a short distance below the line of the inner surface of-the upper end of the box or casing 15 and is coiled once around the fulcrum or pin 38, which pin is extended through the face plate directly op osite the needle bar 14, the end 30 of the 001 which forms the short arm of the lever is extended in an upward direction in a curved line and with said end is connected one end of a coiled spring 40. The other end of the spring is connected with the upper end of a tension regulating arm 41 secured to the innor end of a short bearing or shaft 42, the outer end of which shaft extends transversely through the portion of the face plate lying between the s ots 30 and 34, at a point near the inner line of slot 30 and downwardly from the upper end of the said portion of the face plate the requisite distance to obtain purchase on the coiled spring 40. Upon the outer end of the bearing 42 is connected rigidly one end of a spring controlling arm 43, the other end of which arm extends upwardly a short distance and upon the inner surface of said arm is aprojection 44. Upon the outer surface of the said portion of the face plate between slots 30 and 34 and secured thereto beneath said arm 44 is a rack 45 in the arc of a circle in which arm 43 is movable and with which rack the projection 44 in arm 40 engages. Upon the outer surface and upper end of the face plate 23 outwardly from a vertical line extending through the stud 32 for the tension plates 31 is a thread guide loop or eyelet 46. Upon the inner surface of the portion of the face plate 23 between slots 30 and 34 is a narrow strip or plate 47 which is connected at its upper end to said portion of the face plate above the short arm 30 of the take up and close to the inner surface of the upper end of the box or casing 15, and ex tends past said arm and is 'bent at an angle and extended downwardly parallel with plate 23 as in Fig. 2, its outer surface being in line transversely with the inner side of the slot 34,

and inclined inwardly in a corresponding angle of inclination to the inner side of said slot 34, the lower end of which strip is bent at an angle and extended inwardly to and secured fixedly to the inner surface of the said face plate at a point a short distance below a line extending horizontally through the lower end of said slot 34, thus forming two inclined planes or supplemental take ups for the thread between which the longer arm of the take up lever 36, is operated. The spool of thread which supplies the needle is not shown, it being mounted on the arm of the sewing machine in the usual manner.

In operation the free end of the thread 48 which is drawn from the spool is inserted first through the eyelet 46, thence carried downwardly upon the outer surface of the face plate 23 between the tension disks 31, thence within the lower end of the slot 30, and carried up wardly on the inner surface of the front plate 23, to the carrying pin 26 on the needlebar 14, thence upon the upper surface of said pin past the inner surface of the strip 47 (between the needle bar and said strip) to the outer surface of the-vibrating arm 37, thence in the direction of the inner surface of said vibrating arm 37 to form a loop in the thread thence passed outwardly through the slot 34, thence upon the outer surface of the front plate 23, to the carrying pin 26, and thence upon said pin near the inner surface of the upward extension 27 of said pin thence downwardly to the eye of the needle 19 on the needle bar and through said eye. It is obvious that the end of the thread from the tension disks 32, may be formed in a loop and extended over the portion 35, of the front plate, one portion of the thread extending outwardly through the slot 30 and the other portion out of the slot 34, a space being left between the front plate 23 and thecasing 15 for the loop, as seen in Fig. 2. The loop being drawn downwardly passes over the inner surface of the strip 47, and also ex 1 means for extending the thread over the vibrating arm. A plate 55, extends transversely to the outer surface and lower end of the lever arm 36, and is secured rigidly to the outer end of a screw 56, which screw enters the inner surface of the face plate at a point the requisite distance outwardly toward the outer vertical surface of the face plate to form a stop for the lever arm or a limit to its outward stroke.

Power being communicated to the rotary shaft 12 and cam 16 on the needle bar 14 a vertically reciprocating movement is imp arted to the needle bar and on the downward movement of said bar the loop in the thread on the face plate slips down to the bent portion 36 of the lever arm 36, in the meantime holding up the slackin the thread, it being held up by the bend in the arm and the eleva tion of the arm by the spring until the eye of the needle nearly reaches the fabric, at which time the lever arm 36 comes into contact with the stop screw 56, and ceases to draw upon the thread until the needle has reached its lowest point below the fabric, and when the needle begins its upward movement the loop is formed for the passage of the shuttle. In the upward movement of the needle bar the loop passes over the outwardly bent portion of the lever arm drawing the loop for the setting of the stitch and the spring 40 assisting in setting the stitch in the fabric that is in the position of the lock in the stitch of the upper and lower threads the inclined slot 34 providing for drawing more thread from the spool for the formation of the loop so that the shuttle will readily pass through the loop. In the retraction of the lever arm and the for mation of the loop, the thread obtains two bearings upon the thread carrying pin 26, thus forming the principal take up and slack thread controller, the inclined slot in the face plate acting as a supplemental take up which enables the needle bar to draw more thread than it would by the length of its stroke.

The increase and decrease upon the tension of the spring 40 is controlled by the re spective movements inwardly and outwardly of the arm 43 which arm readily springs outwardly so as to be engaged and disengaged with the teeth of the rack and greater or less degree of power is imparted to the take up arm 36 and therefore affording the desired draw upon the thread.

In the modifications seen in Figs. 5 and 6 the slots 30 and 34 as in'Fig. 1 are in the face plate dispensed with, and the take up lever arm alone employed. In this construction of the lever arm 49 as seen in the latter or modified form the upper end of the lever arm is coiled around the in of fulcrum 50 which pin is connected wit the inner surface of the face plate at precisely the same point as the pin 38 in Fig. 1. In the face plate 50 a short distance downwardly from the fulcrum or pin 48 is a transverse slot 51. At a point opposite said slot the lever arm is bent at 52 outwardly at an angle and extended through slot 51 in the face plate and then bent at 53, and extended downwardly parallel with the outer surface of the face plate to a point 49 a short distance below a horizontal line extending within the u per end of the vertical slot 54 in the face p ate which latter slot is the same as the slot 25 in Fig. 1. From the point 49 the wire or arm is bent at an angle and the lower end extended inwardly in the direction of slot 54, the lower end of the lever arm being bent in a curved line outwardlyas in Fig. 1. The upper short arm 49 is the same as in Fig. 1 and with said arm is connected the coiled spring and spring regulating device shown in Figs. 1 and 3 and arranged in osition and operating as described by said igures.

The flat guard plate 55 prevents the retracting lever arm from being accidentally drawn from its position or bent so as to prevent its efficient operation. The outer end of the plate 55 is rigidly connected with a screw 56 which screw enters the face plate at a point a short distance inwardly from the vertical edge of the face plate. The upwardly extended pin on the needle bar for the thread is bifurcated or slotted at 58 as seen in Fig. 7. In threading the needle the free end of the thread is inserted through the eyelet 46, thence extended downwardly between the tension plates 31 as in Fig. 1, thence upwardly in the direction of the forked pin 57 and over said pin as seen in Fig. 7 thence around the take up arm 49 and thence within slot 58 in the pin 57 thence downwardly to the eye of the needle. The loop may be made in the thread the lower curved end of the take up arm moved inwardly and the loop slipped over said end if preferred.

In the operation of the take up 49 the draw upon the loop is at the minimum when the needle bar is at the limit of its down stroke and upon passing the bend in the lever arm the drawing action upon the loop for the setting of the stitch is effected in like manner as described in Fig. 1. The take up arm may be regulated to vary the draw upon the thread increasing or decreasing its power as the exigencies require.

Such other modifications of the invention may be employed as are within the scope of the invention.

Having fully described my invention what I now claim as new and desire to secure by Letters Patent is 1. In a sewing machine, the combination with a main take up consisting of a self retracting lever arm, fulcrumed upon said machine, the reciprocating needle bar and a thread carrier actuated by said bar upon which the loop in the thread has two bearings, means for stopping the outward move ment of the lever arm, and a take up plate inclined to the needle bar and in proximity to the path of the lever arm.

2. In a sewing machine, the combination with a power actuated reciprocating needle bar and thread carrier over which carrier the loop in the thread has separate bearings and the main take up device comprising a retracting lever arm, upon which the loop formed in the thread slides in the movement of the thread carrier, 'of an auxiliary take up, comprising separate adjacent plates one of which is inclined to the other and to the needle bar, the lever arm being movable to and from the thread carrier.

3. In a sewing machine, the combination with the reciprocating needle bar and thread carrier on said bar and with the front plate having a vertical slot for the thread carrier and separate vertical slots for the thread extending from the upper end of said plate downwardly and having the lower end. of one of said slots inclined to the needle bar, a separate plate adjacent to said latter slot, and secured at its ends to the said front plate, a lever jarm' pivotally connected with the said front plate near the upper end portion thereof and between said vertical slots for the thread, the longer portion of the lever arm being movable toward the thread carrier and between the front plate and the plate adj acent to said slot, and an adjusting device connected with the short arm of the lever.

4. The combination in sewing machines I with the face plate having a centrally located vertical slot, the needle barand thread carrier on said bar within said slot, said face plate having slots extending downwardly from the upper end of the face plate, and a portion of one of said slots inclined at an angle to the needle bar and a self-retracting lever arm or take up for the slack in the thread secured to said face plate between said slots.

JOHN B. FARR. Witnesses GLEN SHERMAN, NYM. l/VALTER BRADY.

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