US2347761A - Stitching machine - Google Patents

Description

J. w. BEDARD sTITcHiNG MACHINE Filed Feb.

'om the spools 60 May 2, 1944.

5, 1941 5 Sheets-Sheetf l INVENTOR MMM lmm, ATTORNEY May 2 1944- J. W. BEDARD 2,347,761

STITCHING MACHINE Filed Feb. 5, 1941 v 3 Sheets-Sheet 2 INVENTOR ATTORNEY J. w. BEDARD STITCHING MACHINE May 2, 1944.

Filed Feb. 5, 1941 3 Sheets-Sheet 3 INVENTOR /Lfovwg ATTORNEY Patented May 2, 1944 UNITED STATES PATENT OFFICE STITCHING MACHINE Joseph W. Bedard,` Hoosick Falls, N. Y. Application February 5, 1941, Serial No. 377,502

13 Claims.

This invention relates to stitching machines, and especially to the thread-feeding mechanism employed in such machines.

In the operation of such machines, the thread is usually pulled directly from a supply spool through a tensioning device and fed to the stitch- 'forming mechanism by means of a so-called ythread take-up device. It has long been recognized, however, that this arrangement is unsatisfactory due, primarily, to the fact that when the withdrawal of the thread from the spool is abnormally resisted as it is frequently by virtue of imperfections in the thread or in the manner in which the thread is wound on the spool an imperfect stitch results.l

In accordance with the present invention, the above noted as well as other diiiculties are obviated by providing such machines with means arranged between the usual tensioning device and the spool and adapted to withdraw a given quantity of thread from the spool and to store the same in slack condition for subselquent use in the formation of a stitch. To this lend, the machine is equipped with an attach- :ment presenting an upper thread supply station arranged in proximity to the spool, a lower :thread receiving station arranged adjacent to the tensioning device, an intermediate spring :actuated clamping device and mechanism controlled from the main drive shaft of the machine operating to transfer alternately rst a given length of thread from the spool to the upper supply station and then from the upper supply station to the lower receiving station during each machine cycle of operation.

In the embodiment of the invention illustrated, such mechanism includes a T-shaped rocker arm provided with a pair of laterally projecting pins or rods-one for drawing the thread from the spool into the upper supply station and the other for transferring the thread thus drawn from the spool into the lower receiving station. The rocker arm is also provided with a cam plate for controlling the operation of the clamping device so that the thread will be held against transfer between the stations as it is drawn from the spool and then freed to permit the transfer of the thread from the supply station to the receiving station from whence it may be drawn to complete a stitch.

For a more complete description of the present invention reference may be made tothe accompanying drawings wherein:

Figure 1l is a side view of the thread-feeding attachmentemployed in the present embodiment of the invention showing the positions of the various parts at one phase of its cycle of operations;

Figure 2 is a perspective View of a thread guide which is employed with the thread-feeding attachment shown in Figure 1; y

Figure 3 is another side view of the threadfeeding attachment employed in the present embodiment of the invention showing the positions of the various parts at another phase of its cycle of operations; Y

Figure 4 is a front view of the thread-feeding attachment, the View being taken along line 4 4 of Figure 3;

Figure 5 is a sectional line 5 5 of Figure 3;

Figure 6 is a perspective view of a modied form of thread guide which may be employed; and

Figure 7 is a detailed view of the rock shaft employed to eect the opening and closing of the thread-clamping mechanism.

In the embodiment of the invention illustrated, the thread-feeding mechanism is presented in the form of an attachment that may be applied to new or used machines of the type that requires three threads to complete a stitch, but it is to be understood that it may be employed with equally favorable results with machines that require the use of-a greater or less number of threads to complete a stitch. In such machines, the threads I4 which usually lead directly from supply spools I8 are drawn through tensioning devices I9 by means of a take-up clevice Il and then delivered to the stitch-forming mechanism (not shown). The manner in which the take-up device Il and the stitch-forming mechanism operates is well known in the art and a` description thereof is not deemed necessary other than to say that the operation is eifected by the main drive shaft I6v of the Amachine which view taken along the lmakes one complete rotation during each machine cycle of operation.A Y g Y The attachment comprises a vertically disposed frame member IS-secured to themain frame of the machine. VThe frame member I5 is provided with'a thread supply station 2| and with a thread Yreceiving station -22 located above and below a 'thread clamping device 3.` 'I'he iframe member Iii is also provided with [a foreand-aft T-shaped rocker arm '28 `which is pivotally secured ltoi theside facev thereof by a stud 26d.V The, rockerjarm 2S at its front end, isl provided with a pair* of laterally disposed. and vertically spaced pinsY 24, 25, behind which the threads lil leading from the spools i8 are trained. The upper pin 26 is adapted and arranged to be carried into and out of the upper thread supply station 2| and the lower pin 25 is adapted and arranged to be carried into and out of the lower thread receiving station 22 as the arm 26 rocks about its pivotal axis.

At its rear end, the rocker arm 26 is provided with a slot 2l through which projects a pin 28 carried by a vertically disposed operating rod 29 at its upper end. The operating rod 29 is slidably mounted in a U-shaped housing 30 (Figure 5) formed in the frame member I5 and closed by a face plate 3| secured thereto by screws 32. The operating rod 29 projects downwardlybeyond the housing 3|) and at its lower end it is pivotally connected by a stud 33 to a connecting link 36 at one end thereof. At its other end, the link 34 is loosely mounted on a stud 35 carried by a disk 36 secured to the main drive shaft I6, the arrangement of parts being such that as the main drive shaft I6 makes one complete rotation during a machine cycle of operation the operating rod 26 moves up and down to rock the arm 26 in opposite directions for limited distances e about its pivotal axis.

A cam 31 having a high portion 36 and a low portion 39 is mounted on the stud 26a and it is secured to the rocker arm 26 by means of a screw 46 so as to move in unison therewith.

The thread clamping device 23 (as best shown in Figure 5) comprises a bushing il and a rod 62, the bushing 4| being threaded through the frame member |5 and forming the stationary part of the clamp and the rod i2 being slidably mounted in the bushing 6| and forming the movable part of the clamp. At its'outer end, the bushing 4| is provided with a clamping face 43 and at its outer end, the slide rod 42 is provided with a knob 44 having a clamping face i5 positioned opposite the clamping face 43. The threads I4 leading from the spools |8 are trained between the clampingv faces 43, 65. When the clamping device 23 is open, that is, when the clamping faces 43, 55 are'apart the threads` are free to travel therethrough, but when thecla'mping device 23 is closed the threads are held against transfer. At its inner end, the slide rod 42 rests against the rounded upper end of a vertically disposed lever 66 secured at its lower end on the inner end of a rock shaft 4l which projects laterally beyond the front side face of the frame member l5. A second vertically disposed ,lever .69 is secured at its lower .end to the outer end of the rock shaft 6l. `At its upper end, the second lever 59 is provided with a pin5| positioned before the face of the cam 5l. A spring52 positioned about the slide rod 42 between a collar E13-mounted adjacent the rear end thereof and the bushing 4| tends to Aforce the slide rod 62 rearwardly to maintain the clamping device 23 closed and the pin 5| on the second vertically disposed lever 46 bearing-'against the face'of the cam 3l.

The -frame member is also provided with'a thread Vdrag i6-comprising a plate 62 slidably mounted on Vand adjusting stud' threaded through a clamping face 64 Yformed on the frame member l5 immediately abovethe upper thread supply station 2|. The three threads Vi6 leadingfrom the supply spools IS'are trained between the plate 62 and the clamping face 6d, and a spring 65 positioned abo-ut the stud 63 acts to forcejtheplatetE towards the face 66 and so exert a predetermined drag on the threads as they pass therebetween.

.The upper thread supply station 2| and the lower thread receiving station 22 are provided with V- shaped members 55, 56 adapted and arranged to guide the thr'eads in xed paths as they travel through the drag device 6|) and through the clamping device 23. To these ends, the members 55, 56 are provided at their ends with holes 6| through whichl the threads l5 are trained and these holes are so spaced and located as to prevent the threads from moving sideways out of the drag device 66 and the clamping device 23 as they travel therethrough. Since the number of threads may vary depending on the sort of stitch desired, the members 55, 56 are adapted and arranged to be replaceable so that the number of holes in the ends thereof will accord with the number of threads employed. For example, if three threads are employed, the members at their ends are provided with three holes (see Figure 2) whereas if fourV threads are employed, the members at their ends are provided with four holes (see Figure 6). In addition, since the members 55, 56 are replaceable, they are also adapted and arranged to be used interchangeably to simplify the problems encountered in the manuiacture and assembly thereof. To these ends, the members 55, 56 may be stamped from spring steel or thelike and they are provided with prongs 5l which may be punched or stamped therefrom and which are adapted to cooperate with notches 55 formed in the frame member |5 to hold them in position.

In operation, the threads leading from the spools |3 are trained through the various parts of the attachment in the manner shown in the drawings and thence in the usual manner through the tensioning devices |9, the thread take-up device and the stitch-forming mechanisms (not shown).

In describing the operation, let it be assumed that the rod 29 which operates the rocker arm 26 is in its lowermost position at the beginning of a cycle of operations (see Figure l). Under these conditions, the upper pin 24 on the rocker arm 26 is loc-ated in the upper supply station 2i, the clamping device 23 is closed, the lower pin 25 on the rocker arm 26 is in its outermost position, and av supply of thread adequate to complete a stitch is stored in slack condition in the lower receiving station 22 from whence it is drawn through the tensioning devices |9 by the thread take-upV il and fed to the stitch-forming mechanism tri-complete a Vstitch during the ensuing cycle'of operations. During this cycle oi operations, `the'mai'n drive shaft i6 makes one complete revolution and the operating rod 29 is thus forced upwardly and downwardly through the medium of the connecting link 3.5 in the man.- ner heretofore explained. As the control rod 29 moves upwardly during the first part of the machine cycle of operations, the arm 26 is ,rocked about its pivotal axis. As the arm 126 rocks about its pivotal axis, 'thejhgh part 36 of the `c am k31 mounted thereon is carried in iront oi Vthe pin 5| ,on the vertically disposed arm 49 andthe rock shaft il is thus rotated. As the shaft 41 rotates, the other vertical arm '56 securedthereto moves forwardly and so forces the slide rod t2 forwardly against the action oi the spring 52 to open the clamping device23 and thus permit the transfer of thread from the uppersupply station 2| to the lower receiving station u22. Also, as the arm 26 Vrocks about its piyotalaxis,

the upper pin 24 mounted thereon is carried out of the upper supply station 2| and the lower pin 25 which isl also mounted thereon is carried into the lower receiving station 22 to eifect the transfer of thread from the upper supply station 2| to the lower receiving station 22 (see Figure 3) As the operatingrod 29 moves downwardly duringthe latter part of the cycle of operations, the arm 255 is rocked in the opposite direction about its pivotal axis back to its initial position. As the arm 2S thus rocks about its pivotal axis, the low part 39 ofthe cam 31 mounted thereon is carried in front of the pin 5| at which time the spring 52 acts to force the slide rod 42 rearwardly and so close the clamping device 23 to prevent transfer of thread between the two stations 2|, 22. Also, as the arm 26 thus rocks about its pivotal axis, the lower pin is carried out of the lower receiving station 22 and the upper pin 24 is carried into the upper supply station 2|. Inasmuch as the clamping device 23 is closed during the travel of the upper pin 24 into the upper supply station 2| thread is drawn from Ythe spools iti through the drag device 66 and stored in the upper supply station 2| from whence it may be transferred to the lower receiving station during the next cycle of operation. The drag exerted on the threads by the device Sil as they pass therethrough is so regulated by adjusting the position of the stud E3 as to prevent a whipping action from taking place; otherwise excessive amounts of thread might be drawn from the spools IB and stored in the upper supply station 2| in a tangled condition.

It is to be noted-that as the lower pin 25 on the rocker arm 26 moves outwardly after transferring a supply of thread from the upper station 2i to the lower station 22, threads are being withdrawn from the lower station 22 through the tensioning devices l@ by the take-up device to complete the stitch. In addition, it is to be understood that in the formation of a stitch requiring two or more threads more thread may be required from one of the sources of supply than from another. Under allconditions, however, it is desirable that at the beginning of a machine cycle of operations, the lengths of the threads stored in the lower station be at least sufficient to insure the formati-on of a complete stitch. To this end, the depth of the lower station 22 and the length of travel of the lower pin 25 on the rocker arm 26 are so regulated that when the pin 25 is in its rearmost position in the lower station 22 the length of the most required thread is in excess of that needed to form a stitch by an amount at least equal to the length withdrawn from the lower station 22 after the pin 25 starts its outward movement; and so that this condition may be obtained the depth of the upper station 2| and the length of travel of the upper pin 24 on the rocker arm 26 are regulated accordingly.

While the present embodiment of the invention, the clamp 23 is closed during the latter part of a machine cycle of operation to permit the thread to be stored in the upper supply station 2| and then opened during the early part of the next machine cycle of operation to permit the transfer of the thread from the upper supply station 2| to the lower receiving station 22, other arrangements may be employed depending on the type of machine in which the invention is incorporated. For example, in certain type machines just the reverse might be desired, that is to say, the clamp may be closed during the early part of a machine cycle of operationto permit the thread to be stored in the upper supply station and then opened during the latter part of this machine cycle of operation to permit the transfer of the thread from the upper supply station 2| to the lower receiving station 22.

In the accompanying drawings, the invention has been shown merely by way of example and in preferred form, and obviously many variations and modifications may be made therein which will still be comprised within its'spirit. It is to be understood, therefore, that the invention is not limited to any specific form or embodiment, except insofar as such limitations are specified in the appended claims.

Having thus dened my invention, what claim 1s:

1. An attachment for stitching machines presenting a thread storage supply station, a thread storage receiving station, and a rocking member operable rst in one direction to draw a given length of thread from a source of supply and store the same in said supply station and then in another direction to transfer the thread from the supply station to the receiving station and store the same therein.

2. The attachment set forth in claim 1 including a clamping device arranged between the two stations and operable to prevent the transfer of thread between the two stations While the thread is being drawn from the source of supply and stored in the supply station.

3. An attachment for stitching machines comprising a frame member having a thread storage supply station, a thread storage receivingstation, and a rocking member operable from the main drive shaft of the machine and operable when rotated in one direction to draw a-given length of thread from a source of supply and store the same in said supply station and then when rotated in another direction to transfer the thread from the supply station into the receiving station and store the same therein.

4. A thread-feeding device for stitching machines presenting a thread storage supply station adapted to accommodate a length of thread from a supply spool, a thread storage receiving station adapted to accommodate the thread from the supply station, a rocking member for transferring the thread from the supply station to the receiving station, and means for preventing the transfer of thread between the two stations while a new length is being deposited in the supply station.

5. A thread-feeding device for stitching machines presenting a thread storage supply station adapted to accommodate a length of thread drawn from a supply spool, a thread storage receiving station adapted to accommodate thread drawn from the supply station, a rocking member operable to transfer alternately iirst a length of thread from said spool to the supply station and then to transfer said thread from the supply station to the receiving station, and clamping means operable to hold the thread against transfer from the supply station to the receiving station during the first transfer operation and to release it during the second transfer operation.

6. In a stitching machine equipped with a thread take-up device and a thread supply spool, the combination of a thread-feeding attachment presenting a clamping device, a supply station arranged between the clamping device and the spool and adapted for the storage of thread therein, a receiving station arranged between the clamping device and the thread takeup device and adapted for the storage of thread therein. and a rocking member operable to transfer alternately first a length of thread from the spool to the supply station and then to transfer the thread from the supply station to the receiving station.

7. In or for a stitching machine, a thread-feeding device comprising a thread storage supply station and a thread storage receiving station anda rocking member operable during one phase of a machine cycle of operation for withdrawing thread from aV supply spool and storing it in said supply station and operable during another phase of a machine cycle of operation for transferring thread thus stored into the receiving station for subsequent use in the formation of a stitch.

8. In a stitching machine, the combination oi a thread storage supply station and a thread storage receiving station, a rocking member operable during one machine cycle of operation for withdrawing thread from a supply spool and storing it in said supply station and operable during the next machine cycle of operation for transferring thread thus stored into the receiving station for subsequent use in the formation of a stitch, and guide members through which said thread passes as it travels into and out of said stations.

9. In a sewing machine, the combination oi a thread clamp, a thread storage supply station and a thread storage receiving station located on opposite sides of said clamp, and a rocking member for alternately maintaining said clamp closed and for withdrawing thread from a supply spool and storing the same in said supply station and for thereafter maintaining said clamp open and transferring a portion of the thread thus stored into the receiving station for subsequent use in the formation ofY a stitch.

i0. In a stitching machine, the combination of a clamping device, a thread storage supply station and a thread storage receiving station located on opposite sides of said device, a rocking member for alternately opening and closing said device during a machine cycle of operation, and means for withdrawing thread from a sup` ply spool and storing the same in said supply station when said device is closed and for transferring a portion of the thread thusl stored into the receiving station when said device is open 11. In a stitching machine, the combination of a clamping device, a thread storage supply station and a thread storage receiving station located on opposite sides of said device, means for alternately opening and closing said device during a machine cycle of operation, and a rocker arm for withdrawing thread from a supply spool and storing the same in said supply station when said device is closed and for transferring thread thus stored into the receiving station when said device is open.

12. In a stitching machine, the combination of a clamping device, a threadI storage supply station and a thread storage receiving station located on opposite sides of said device, means for alternately opening and closing said device during a machine cycle of operation, and a rocker arm for withdrawing thread from a supply spool and storing the same in said supply station when said device is closed and for transferring a portion of the threadv thus stored into the receive ing station when said device is open, said device actuating means and said thread withdrawing and transferring means being actuated by a rotating element of the machine.

13. In a stitching machine, the combination of a clamping device, a thread storage supply station and a thread storage receiving station located on opposite sides of said device, means for closing said device during the latter part of a machine cycle of operation and for opening it during the early part of the next machine cycle of operation, and a rocker arm for withdrawing thread from a supply spool during the latter part of a machine cycle of operation and storing the same in said supply station while said device is closed and for tranesferring during the early part of the next machine cycle thread thus stored into the receiving station while the device isopen.

JOSEPH W. BEDARD.

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