US1884177A - Sewing machine - Google Patents

Description

W. N. PARKES SEWING MACHINE Oct. 25, 1932.

Filed Oct. 29, 1929 2 SheetsSheet IN V EN TOR.

Oct. 25, 1932. w, N. PARKES 1,884,177 SEWING MACHINE Filed Oct. 29, 1929 2 Sheets-Sheet 2 u illllm II L I Ill-III i y I 1% II!" I. l

QT} 6 INVENTOR.

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Patented Oct. 25, 1932 UNITED STATES PATENT OFFICE WILLIAM N. PARKES,OF BROOKLYN, YORK, ASSIGNOR TO THE SINGER MANU- FACTURING COMPANY, OF NEW. YORK, Y., A CORPORATION OF NEW JERSEY SEWING MACHINE Application filed October 29, 1929. Serial No. 403,213.

This invention relates to rotary hook lock stitch sewing machines. Herein it is preferably illustrated and described, as I have constructed, incorporated, and tested it, in a full size working rotary vertical'hook machine. Only so much of the said machine is illustrated and described herein, as it is thought necessary. for an understanding of the working of the machine with the invention in it,

' The main'object of the invention is to 1mprove the take-up device illustrated and described in my co-pending application, Serial Number 377,258, filed July 10, 1929, I

In connection with a take up device it will be remembered that such a device in a rotary hook lock stitch machine functions to provide the loop for the hook to engage, develop, and pass around the bobbin case, then it functlons .to take-up this loop, and finally it functions gI- in connection with thesettingof the stltch.

The invention consists of the improvements I have made in the said take-up device, as herein illustrated in the drawings, described in the specification, and specifically set forth 3 in the claims.

Referring now to the drawings: Fig. l is a perspective front view of the stitching end of the head of the machine embodying the invention. In this view the needle thread. the parts of the stitching mechanism, and the arm of the opener device, are illustrated in about the relative position they are in, at the time the beak of the hook commences to enter the loop of needle thread.

Fig. .2 isa complete bottom plan view of of some of the parts, illustrating the relative position of these parts, and of the needle thread, at about the beginning of the setting of a stitch.

7 Fig. 4 is a side view of Fig. 3, looking in the direction of the arrow; illustrating the relative position of the parts and the needle thread of the said Fig. 3, at about the finishingof the setting of a stitch.

Fig. 5 illustrates the parts, and needle thread, in full linesof Fig. 4, in the relative position they are in at about the time the takeup, in its take-up movement, has drawn up the loop of needle fthreadvto the position shown in Fig. 6; and with the needle thread, and the end of the take-up lever, in dotted lines in the position they are in at the time the'needle commences to enter the work. I

Fig. 6 is a bottom plan View of the needle plate, illustrating the loop of needle thread being drawn between the edge of the needle hole, and the section of the bobbin threadthat extends from the bobbin to the work.

Fig. 7 is a' view illustrating the position of the bobbin case relative to the opener arm, and toe reverse movement stop, and the forward movement stop, at about the time the loop of needle thread has been drawn to the position shown in Fig. 6.

In the drawings, 1, represents the stitching end of the overhanging arm, and 2, the stitching end of the bed of the machine.

In usual bearings, located on the underside of the bed of the head of the machine, is

shown, is of the same diameter as the pulley 5, therefore it will be understood that when the machine is operated the hook shaft 3 revolves in unison with the driving shaft 7.

To the underside ofthe bed 2 of the machine, is s'ecured by means of screws 8, a hook saddle 9. The forward end of the shaft 3 is journalled, in a usual way in a bearing carried by the hook saddle; the'end of the shaft extends beyond the bearing, and to this end issecured a bevel gear, not shown. In usual hearing in the hook saddle, a short vertical shaft'lO is journalled, which is indicated by dotted lines Fig. 2. On this short vertical shaft a bevel gear not shown, is secured. The

bevel gear, which'is attached to the end of the shaft 3, is double the size of the vertical shaft bevel gear with which it is in engagement. From this it will be understood that the shaft 10 revolvestwice to'each revolution. of the shaft 3. To the top of the short vertical shaft 10 is secured, in a usual way, a vertical hook 11, that carries a bobbin case 12, in which is located a bobbin 13.

A short vertical opener shaft 14 is suitably journalled in the hook saddle, and this opener shaft is preferably oscillated once to each. stitch by any suitable means. To the top of the opener shaft is secured an opener arm 15, which is provided with an end 15a, that engages the bobbin case 12, once to each stitch. (Figs. 1 and 2.)

The numeral 16 represents a needle thread tension device, and 17 represents the free end of the take-up lever through which is formed a thread eye 18. This lever is suitably pivoted on a pending link, not shown, and is operated by means fully shown. and described in my said co-opending application, Serial No. 377,258. In a suitable bearing is located a pressure bar 19 of usual form. To the lower end of this bar is secured the shank 20, of a usual form of tilting presser foot 21.

The numeral 22 represents theneedle plate (Fig. 6) through which is formed a needle hole 23. From the underside of the plate there project downwardly a small special form of a bobbin case stop lug 24. In a. groove 25, formed across the under side of the rear end of the needle plate, is ustably secured a bobbin case reverse movement stop 26, which is provided with an extending part that has a free end 27. On the underside of the needle plate, laterally from the needle hole, is formed a narrow loop guard groove 28.

The bobbin case 12 is provided with an abutment 29, that is adapted to cont-act with the small lug 24, of the needle plate, and thereby the case is held from being turned, in the direction that the hook turns when the machine is operating; the direction that the hook turns is indicated by the arrow Fig. 1. The bobbin case is provided with a second abutment that is adapted to contact with the end 27 of the bobbin case reverse movement stop. The bobbin case is provided with a third abutment 31, that is adapted to be engaged by the end 15a of the opener arm.

It will be observed that the reverse movement stop is secured in the groove 25 of the needle plate, by screws 32, and that these screws pass through slots 33 and 34 which are formed through the stop, and thereby means is provided for adjusting the stop to determine the extent that the bobbin case may move in the opposite direction to that in which the hook revolves.

The needle thread runs from the sup- 1V to ways formed throu h elbow thread l :1

guide 355 and from there to the tension 16; and from this tension it passes to,, and through, the thread eye 18 of the take-up lever; and from the take-up it passes to thread guides 36 and 37 respectively. From here the needle thread passes to and through a thread guide, not shown, which is formed in the lower end of a needle bar 38, and then the thread passes to the eye of a needle 39 with which the needle bar is provided.

The bobbin thread 40, (Fig. 1) passes from the bobbin 13,,under a bobbin threadtension spring 41, andfrom there to and through the needle hole of the needle plate to the work.

To thefront side of the end of the overhanging arm of the machine (Fig. 1) is secured by screws, not shown, a take-up guard plate 42 that is located in a vertical plane. This plate is provided with an edge part 43, that'is located at an angle with respect to the vertical, asbest shown in Figs. 4 and 5. I The main function of'the said angular edge 43 is to hold the section of the needle thread 35, that extends from the thread eye 18 of the take-up lever to the thread guide 36, into engagement with the stitch setting part or arm 45, during the process of setting the stitch. The location of the said angular edge is such. relative to the said stitch setting part 45, and the part 36a of the thread guide 36,

that it, the said angular part, holds the said section of the needle thread into positive en gagelnent with the stitch setting part 45, from the beginning to the finishing of the setting of a stitch.

In Fig. 5, the position of the needle thread in full line is about as it is at the beginning of the setting of a stitch, in Fig. 4, the position of the needle thread is shown in full line at about the position it is in at the finishing of the setting of a stitch, and in Fig. 5, the position of the needle thread is shown in dotted line at about the position it is in, after the completion of the setting of a stitch and just previous to the said thread being drawn from the stitch setting part; and, in Fig. 1 the position of the needle thread is shown in full line at about the position it is in after it has been disengaged from the stitch setting part.

To the plate 42, is secured, by means of a nut 44, a slack thread control and stitch setting part or arm 45. The said arm is provided with a base 46, and from this base a reduced and threaded end 47 extends freely through a bore in the plate, and on the said end 49. the nut 44 is located, and serves as means for drawing the base of the arm firmly in place against the side of the plate, in any desired angular position, around the axis of the end 47 of the arm.

The said arm from its base to its end 47a is tapered. From its said base to about 48 (Fig. 4) the arm extends, at a slight angle to the vertical, towards the front of' the machine, and from here to about 49, it extends at a slight angle to the vertical towards the back of the machine, and, from 49; section 50 of the arm, extends at an acute angle to its end 47a. Looking at the front of the arm, (Fig.3) it will be seen that from its base down to about 49 the arm extends at, a slight angle away from the side of the plate 42, and that from here it extends to its end parallel with the side of the plate.

The end 17a of the said arm 45 fits and is located in a small vertical slot 51, which formed in a covering plate 52, that is secured by screws 53, to the arm of the machine, and thereby means is provided for adjusting the arm around on the axis of its base. of the slot a socket may be formed in the said covering plate, into which the end 47a'oi the said arm may fit, and thereby the said end may be held in a fixed position. In testing the machine, from the very light to the very heavy work applicant has found no necessity for adjusting said arm, after it has been properly located.

In the operation of the machine, just previous to the parts of it, and of the needle thread, reaching the position illustrated in Fig. 1, the part a of the needle thread has been thrown downwardly to about the position indicated in the said figure. In this connection it ispointed out that the relative position of the tenson device 16, the thread carrying end of the take-up, the slack thread control and stitchsetting arm and the part 366; of the thread guide 36, causes the thread to be thrown down in the position illustrated, just previous to the beginning of the upward movement of the needle bar. The beginning of this movement it will be remembered causes the beginning of the for mationof a loop of needle thread.

The object here, is, to have the construc tion of the arm &5, and its relative position to the other parts mentioned, such, that in the operation or" the machineall the slack needle thread Will be on the right of the part 3604 of the thread guide86. at the time the formation of the loop of needle thread begins. The purpose of this is to keep the part of theneedle thread, which extends from the guide 36 down and through the eye of the needle, from flushing or flowing down, and thereby; disturbing the proper formation of the loop.

In the usual sewing machine, with certain kinds of fine thread, especially with fine silk thread, much trouble is caused by theflushing down of the slack thread at the, time or just previous to the formation of the loop. The trouble referred to 18 the cutting oft of the thread, the breaklng of the thread, theskippingof stitches etc.,especially, under h 7 speed. In connection with the flowing down of the thread through the work, it will be remembered that there is a vertical groove in the needle which provides a free passage for the thread through the work when the needle is in the work, as it is when the saidloop is formed. f

In my said copending application 377,258, the slack thread control and stitching setting arm is constructed so that it, in combination In place the hook enters the loop, and at. this point there is enough slack thread held in reserve for the rapid beginning of the drawing of the thread for the loop which takes place about this time.

In the further operation of the machine from the position shown in the said Fig. 1 the end 18 of the take-up lever moves downwardly, rapidly enough to provide slack. thread freely for the use of the hook in developing and passing the loop of thread around the bobbin case. At the time the beak of the hook commences to enter the loop of needle thread, there is a free passage for the loop between the abutment 30 of the bobbin case and the end 27 of the reverse movement stop, and between the abutment 31 of the bobbin case, and the end 1555 of the opener arm, as shown in the said Fig. 1.

The opening between the end 27 of the reverse movement stop and the abutment 30 of the bobbin case remains completely open until after the hook has carried the loop by, but, previous to the passing of the loop by the abutment 81 of the case, the opener arm commences its functioning stroke, so that at the time theloop passes the abutment 31, there only enough opening between the abutment 31 of the case, and the end 15a of the opener arm, for the loop to pass by freely. Immediately after the loop has passed the saidjabutinent3l, and the end of the opener arm, this end of the arm engages the abutment and moves the bobbin case to provide an opening betweenthe stop lug 24 of the needle plate, and the abutment 29 of the bob-.

the bobbin case, to move the case in the direction that the hook moves, and thereby cause the section 56 of the bobbin thread to be slack, which in turn provides a free passage for the loop between the edge of the needle hole 23 and the said section 56 of the bobbin thread. Referring further to the construction and operati on 01: the machine, the numeral 54 represents the closed path of travel of the thread carrying eye 18 of-the free end of the take up lever.

trated in Fig. 5, to about its position as illustrated in Fig.3, the complete process of the setting of the stitch takes place, and in this connection attention is specifically drawn .to the very slow action on the thread of this During the movement of the said free end of the lever, from its position illusprocess of setting the stitch. It will be observed that the tapered construction of the stitch setting part 4:5, and its being formed into an elbow, at the beginning of the stitch setting functioning part of it, taken in connection with the path of the thread carrying eye 18 of the take-up lever, all contribute to the bringing about of the slow action referred to, and thereby the bringing about of a ma terial increase in the speed at which the stitch may be set without breaking the thread.

Another point to which special attention is drawn: the relative location and construction of the edge 43, of the plate 42, and of the stitch setting arm 45, are such that at the finishing of the setting of the stitch, as illustrated in Fig. 4, the movement of the end of the take-up lever has brought the thread carrying eye 18 of it to a point where the needle thread commences to be held slack over the arm 45, and this slackness of the thread commences in time to provide for the varying thicknesses of the work, that is to say, the thread becomes slack or free in time for the ieedle to commence to draw it, previous to the eye of the needle reaching the thickest work the machine is constructed to do.

Applicant notes that in view of the fact that it is evident that changes can be made in the construction, and relative location of parts, of his invention, and for other reasons, he does not wish to be limited to the preferred form herein disclosed.

Having now described my invention, what I claim as new is:

1. In a lock stitch sewing machine, a thread carrying needle, means for moving a section of the needlethread leading to the needle around a field, a fixed stitch setting and slack thread control part which has body portionthat terminates into an end portion, the body portion of the part located within the said field, and the end of the end portion located outside of the field.

2. In a lock stitch sewing machine, a thread carrying needle, means for moving a section of the needle thread leading to the needle around a field, a fixed stitch setting and slack thread control part which has a body portion that terminates into an end portion, the body portion located within the said field substantially parallel with a portion of its edge, and the end of the end portion located outside of the field.

3. In a lock stitch sewing machine, a thread carrying needle, means for moving a section of the needle thread leading to the needle around a field, a stitch setting and slack thread control part which has a base portion that terminates into an end portion, the base portion detachahly secured to a fixed part of the machine, the body portion from the base to its end tapered, the body portion located in the field near its edge, and the end of the end portion located outside of the field.

4. in a lock stitch sewing machine, a thread carrying needle, means for moving a section of the needle thread leading to the needle around a field, a fixed stitch setting and slack thread control part which has a body portion that terminates into an end portion, the body portion of the part located within the field and the end of the end portion located in a slot which is formed in a part which is attached to the machine.

5. A stitch forming mechanism for lock stitch sewing machines comprising an operating thread carrying needle, an operating takeup lover, a fixed stitch setting and slack thread control part which has a body portion that terminates into an end portion, the said part so constructed and located that its body portion projects downwardly at an angle to the plane in which the take-up lever operates, a suitable housing formed in a detachable part of the machine into which the end of the end portion of the said part projects, and the take-up lever and the part so located relatively that previous to the beginning of the setting of a stitch the lever brings the needle thread into engagement with the said part.

6. In combination in a lock stitch sewing machine, a thread carrying needle, a thread guide, a lever that has a free end which is provided with a way through which the needlethread passes to the thread guide, the thread guide and the said way so located relatively that the section of thread that extends from the way towards the thread guide is located in a plane at an angle to the horizontal, means for operating the lever bodily so that the said free end of it moves in a vertical plane around a field and thcreby'moves the section of the needle thread that extends from the way towards the thread guide around a field, a fixed stitch setting and slack thread control part which has a body portion and an end portion, the body portion of the said part so located that it extends into the said field, and the end portion so located that the end of this portion is located outside of the said field.

7. In a lock-stitch sewing machine, a reciprocatory needle, a take-up member adapted to carry a portion of thread leading to the needle in a path around a field, and a slackthread controlling element disposed adjacent to and shaped to substantially conform with the outline of the thread drawing up side of said field.

8. In a lock-stitch sewing machine, a vertically reciprocatory needle, a take-up member adapted to carry a portion of thread leading to the needle in a path around a vertical 0" with the outline of the thread drawing up side of said field.

9. In a lock-stitch sewing machine, a reciprocatory thread-carrying needle, a take-up member adapted to carry a portion of thread leading to the needle in a path around a field, and a fixed stitch-setting and slack-thread controlling part terminating at its opposite ends in the frame of the machine, one end of said part having a thread-engaged shoulder extending into said path in position to coact with said take-up member at the time of the final drawing up of the. needle-thread to set a stitch. i In testimony whereof I'have signed my name.

WILLIAM N. PARKES;

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