US1717180A - berger - Google Patents

Description

June 11, 1929. B E 1,717,180

STITCI-IING MECHANISM FOR SEWING MACHINES Original Filed Nov'. 24, 1922 4 SheetsSheet l June 11, 1929. BERGER 1,717,180

STITCHING MECHANISM FOR SEWING MACHINES Original Filed Nov. 24. 1922 4 -Shee ts-Sheet 2 g J g 3 I ,Z

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STITCHING MECHANISM FOR SEWING MACHINES Original Filed Nov. 24. 1922 4 Sheets-Sheet s June 11, 1929. J] B R ER 1.717.180

STITCHING MECHANISM FOR SEWING MACHINES Original Filed Nov. 24. 1922 4 Sheets-Sheet 4 Patented June 11, 1929.

JOSEPH BERGER, OF UTICA, NEW YORK,

1 s'r s ASSIGNOR TO UNION SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

STITCHING MECHANISM FOR SEWING MACHINES.

Original application filed November 24, 1922, Serial No. 602,990. Divided. and this application filed November 14, 1923.

The invention relates to new and useful improvements in sewing machines, and more particularly to the means for laying the threads on the upper face of the material in a hat sewing machine.

An object of the invention is to provlde a stitching mechanism including a pair of needles, and means for forming a loop in one needle thread above the material, and positioning the same for the other needle to enter said loop, the needle carrying the thread 1n which the loop is formed being positioned relatively higher than the point of the other needle to facilitate the getting of the needle into the thread loop.

Another object of the invention is to provide a thread laying mechanism of the above type with a thread hook for forming a loop in the needle thread, which thread hook is pivoted so as to swing in the arc of a circle extending from a point in advance of the needle carrying the thread in which the loop is formed to a point in rear of the other needle A still further object of the invention is to provide a thread laying mechanism of the above type with a thread finger which moves across the path of the needle carrying the thread in which the loop is to be formed so as to engage said needle'thread, and deflect the same forward of the needle for the hook to engage said thread.

These and other objects will in part be obvious and will in part be hereinafter more fully disclosed.

In the drawings which show by way of illustration one embodiment of the invention- Figure 1 is a front view of a portion of a machine embodyingv my improvements;

Fig. 2 is anJend view of the same;

Fig. 3 is a View partly in plan and partly in section showing the presser foot, the needles, and the manner of mounting the thread hook which cooperates with the needles;

Fig. 4 is an enlarged detail in front view showing the thread'finger just after it has come into engagement with the left-hand needle thread;

Fig. 5 is a plan view of the parts shown in Fi 6 is a View similar to Fig. i, but shov ing the thread hook as moved to a point Serial No. 674,691.

wherein the thread is just about to slip off from the thread finger;

Fig. 7 is a view similar to Fig. 4, but with the hook having moved still further forward so that the thread has slipped from the end of the finger;

Fig. 8 is a view similar to Fig. 7, but showing the needles as having descended to a point so that the point of the righthand needle has passed in front of the lower strand of the loop carried by the hook, while the upper-strand of the loop carried by the hook lies in frontof the right-hand needle;

Fig. 9 is a view similar to Fig. 8, but showing the loop as carried to its extreme righthand position and the needle well down into the loop, and

Fig. 10 is a detail in plan showing parts positioned as in Fig. 9.

My invention relates to sewing machines, and more particularly to a sewing machine which is adapted for sewing hat sweats. The stitch formed is of the character shown in the patent granted to R. R. Hughes, February 19, 1918, No. 1,257,239. The machine includes two needles which are so positioned as to the hat sweat being stitched, that one needle passes through a hat sweat, while the other needlepasses over the edge of the hat sweat. The needle thread loops formed by the needles beneath the plane of the material are connected by a single looper thread.

The present application is a division of my prlor application Serial No. 602,990, filed November 2 1, 1922. and in this divisional application, the particular looper mechanism which I use in my machine is described in detail and claimed therein. Cooperating with the two needles above the material is a thread finger which is mounted so as to move across the path of the left-hand needle, which is the needle that enters the hat sweat material. The purpose of this finger is to deflect the needle thread of the left-hand needle slightly forward, so that it can be engaged by an oscillating hook which forms a loop in this needle thread and positions the same for the right-hand needle to enter. This hook is mounted to swing in the arc of a circle and moves from a point in front of the lefthand needle to a point slightly in rear of the ri ht hand needle. In order to get this movement the hook, theaxis oi? the hook is in rear of the needles, and at the left of a vertical plane parallel with the line of feed and passing between the needles. The hook after it has engaged the needle thread is timed so as tomove and carry its loop to such position where the strand of the loop running from the hook to the previous stitch will lie in rear of the path of the right-hand needle, while the strand of the loop running from the hook to the eye of the left-hand needle is in front of the right-hand needle.

Referring more in detail to the drawings, I have shown my improvement as applied to a sewing machine having a work support 1, and an overhanging arm 2, in which the needle bar 3 reciprocates. The needle bar carries two needles 4 and 5, which are set in the needle bar so that the needle 5 has its point raised to a point considerably above the position of the point of the left-hand needle. Co-

operating with the needles 4 and 5 is a threaded looper 6 which moves into the needle thread loops when moving from a position at the left of the left-hand needle to a position at the right of the right-hand needle. Inother words, the looper movestoward the edge'ol the material when it enters the needle thread hand needle first, and whilcthei needles are going up, and canbe properly set so as to 7 pass the needle slightly above the eye thereof.

By the time the point of the looper has reached the right-hand. needle, the eye of the right hand needle will hav'e moved up considerably so that a proper thread loop is formed for the looper to enter, and yet the looper passes the needle at a point well above the eye so thatthe entering of the needle thread 1001) is assured. i

T he material is held on the work support by a presser foot 7 carried by a presser bar 8 mounted in the head of the machine. Assomated with thismain presser bar 8 is an auxiliary presser bar 9 which is of the usual construction. The material is fed across the work support by a feed dog 10. Cooperating with the needles for forming the loop in the thread of the left-hand needle is a thread hook 11 and cooperating with this thread hook is a thread finger 12. The thread finger 12 is carried by a lever 13 pivoted at 14 to a bracket 15, which in turn is clamped to the main presser bar so that when said presser bar is raised and lowered, this bracket will 'be raised and lowered with it. Mounted on the needle bar is an arm lti-which projects rearwardly therefrom and carries a bracket 17. A; link 18 is pivoted to this bracket and will operate through this link to Vibrate the lever. The link is so set that it moves from an inclined positionwhen the needle bar is clear up to a position which is substantially horizontal, and as a result, when the needle descends, the link will force the upper end of the lever toward the front of the machine, and this will retract the thread linger, while, when the needle goes up, the link will draw in on the upper end of the lever and thus force the thread linger across the path of the left-hand needle, and the finger will engage the needle thread and deflect the same for- Rvard ol' the path of the needle.

The thread hook 11 is mounted on the end of a lever 19. On the end of this lever, there is a sleeve, and the hook has a shank journaled on the sleeve and rigidly held in set positions by screws 20. Mounted on-the lower end of theauxiliary presser bar is a bracket 21. Said bracket has an arm 22 which projects forwardly therefrom and is secured to the main presser bar which makes a very rigid mounting for the bracket. The lever 19 which carries the hook 11 is pivotally mounted on this bracket. The pivot for the lever is indicated at 28. It will be noted that this pivot 23 is well to the left of a vertical plane passing between the needles and parallel with the line of feed. As a result, the hook will swing in the arc of a circle as indicated in Figs. 3 and 5 of the drawings. This path of the hook extends in "front of the left-hand needle, and'thence in front of and slightly to the rear of the right-hand needle. The purpose of this particular movement will be relerre'd to later. The lever 19 carrying the hook 11 is provided with an arm 24-. A link 25 connected to this arm 2-1 and to a depending arm 26 carried byashaft 27 at the rear of the machine serves as a means 'loroscillating the hook. This shaft 27 is inIturn oscillated by an eccentric rod 28 which cooperates with an eccentric on the main shaft beneath the work support.

By referring to Figures 4 to 9, inclusive, it is thought that the operation of my machine will be made clear. When the needles are rising from the material, the thread finger 12 will move across the path o'ithe left-hand needle and engage the thread. thereof-which runs from the eye of the needle to the fabric, and deflect the same forward to a position where the thread hook 11 can engage-the same. It is noted thatthis thread hook as clearly shown in Fig. 10 of the drawings, has a projecting hook point on its lower face, which passes in rear of the left-hand needle thread, so that this left-hand needle thread is drawn into the throat of the hook 11. The thread hook then moves to the right and forms in the left-hand needle thread a loop, one strand of which extends from the throat of the hook to the needle eye, and the other strand of which extends from the throat of the hook to the fabric. This strand of the loop extending from the throat of the hook to the fabric, is at this time, in engagement with the thread finger. As the hook continues on its movement to the right, it will draw the strand along the thread finger, and said thread will finally snap off from the end of the finger.

Just before the thread hook comes into engagement with the left-hand needle thread, the feed of the fabric begins, and this, of course, carries the point where the thread is anchored in the fabric by the previous stitch, rearwardly. The thread finger, however, will hold the needle thread forward a sufficient distance to be caught by the hook. When the thread snaps off from the end of the thread finger, then it will take a straight line position from the throat of the hook to the fabric, for the reason that this left-hand needle thread is slightly under tension during this handling of the thread, and furthermore, the

finger by deflecting the thread, together with the deflection given to the thread due to the forming of the new loop therein, draws the thread tight. This straight line position of the thread after it slips off from the end of the thread finger, extends from the throat of the hook to the fabric as above noted, and as the fabric continues its backward movement to finish the stitch length feed thereof, and the hook continues its movement to the right and slightly in rear of the needle, this lower strand running straight from the throat of the hook to the material will be carried in rear of the path of the point of the right-hand needle, so that said righthand needle will pass in front of this lower strand of the loop. The strand, however, is carried across the path of the point of the right-hand needle just before the point of the needle reaches thelevel of this strand of the thread, and as a result, the upper strand of the thread loop formed by the hook which runs from the throat of the hook to the eye of the left-hand needle is so positioned as to engage the body of the needle on the front face thereof. In other words, one strand of the loop is positioned by the hook in rear of the right-hand needle, and the other strand in front of the right-hand needle, so that the right-hand needle can go down into the loop and thus secure the loop formed-by the thread hook. The thread hook is then retracted and releases this thread loop on to the right-hand needle. It will be understood, of course, that boththe thread loop of the left-hand needle and the thread loop of the right-hand needle, are joined by a looper thread beneath the material, and this of course, locks the loop formed in the thread of the left-hand needle when the stitch is completed. In other words, the loop of the thread of the right-hand needle is secured by the looper thread, and the loop formed in the thread of the lefthand needle is in turn socured by the loop formed in the thread of the right-hand needle.

t will be noted that the thread finger and the thread hook are both mounted either on the main presser bar or the auxiliary presser bar, and these presser bars are both lifted simultaneously when the presser foot is lifted from the fabric, or when the presser foot is raised slightly, owing to an increased thickness of the fabric. As a result, both the thread hook and the thread finger are automatically positioned for varying thicknesses in the material, and are automatically raised when the presser foot is raised for the removing of the material.

It is obvious that minor changes in the details of construction and the arrangement of the parts may be made without departing from the spirit of the invention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire to secure by Letters-Patent, is

1. A sewing machine including in combination, a work support, a presser foot, a presser bar carrying said presser foot, a needle bar, a pair of needles carried by said needle bar, a threaded looper cooperating with said needles beneath the work support, a thread finger movable back and forth in a plane at right angles to the plane of the needles for engaging the thread of one of said needles and deflecting the same forward of said plane, a thread hook, a lever carrying said thread hook, said lever being pivoted to swing about a fulcrum located in rear of the presser bar and at one side thereof whereby said hook will move in the are of a circle from a point in front of one needle to a point in rear of the other needle.

2. A sewing machine including in combination,a work support, a pair of needles having the point of one needle set higher than the point of the other, a thread finger movable back and forth in a plane at right angles to the plane of the needles and be. neath the needle with the highest set point, a thread hook, and means for supporting and moving said thread hook in a curved path from the point in front of the needle with the highest set point to a point at one side of the needle with the lowest set point, said thread hook being adapted to engage the needle thread deflected by said finger for forming a loop therein for the needle with the lowest set point to enter.

In testimony whereof, I aflix my signature.

JOSEPH BERGER.

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