US1981119A - Buttonhole sewing machine - Google Patents

Description

Nov. 20, 1934. J. H. PIKUL BUTTONHOLE SEWING MACHINE.

3 Sheets-Sheet 1 Filed Jan. 26, 1934 1 \nvenTor. doseph H. P1KU| WW;

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Nov. 20, 1934. .1. 1-1. PlKUL BUTTONHOLE SEWING MACHINE Fild Jan. 26, 1934 3 Sheets-Sheet 2 lnvenTor.

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NOV. 20, 1934. J PIKUL 1,981,119

BUTTONHOLE SEWING MACHINE Filed Jan. 26, 1934' 5 Sheets-Sheet 3 lnven'for.

\Joseph H. PIKUI b faWWkW AITys.

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Patented Nov. 20, 1934 UNITED STATES BUTTONHOLE SEWING MACHINE Joseph H. Pikul, Boston, Mass, assignor to The Reece Button Hole Machine Company, Boston, Mass., a corporation of Maine Application January 26, 1934, Serial No. 708,414

11 Claims.

This invention relates to buttonhole sewing machines and it has for one of its objects to provide improvements in buttonhole sewing machines by which the machine is brought to rest at the end of any buttonhole sewing cycle with the work in a favorable position, as regards the needle, for removal from the work-holding means Without danger of becoming caught on the needle. In other words, one of the purposes of the invention is to provide a novel construction in which, when the sewing machine comes to rest at the end of a buttonhole sewing cycle, the work-holding means and the stitch-forming mechanism are in such relative position that the work can be readily removed from the clamps without requiring any particular care on the part of the operator to prevent the work from catching on the raised needle.

Another object of the invention is to provide improvements by which the time involved in completing any buttonhole sewing cycle may be reduced without actually increasing the speed of operation of the stitchforming mechanism.

In mam; buttonhole sewing machines the work-holding means and stitch-forming mechanism not only have a relative feeding movement during the stitching along the sides of the buttonhole, but after the stitching on the buttonhole has been completed and the stitch-forming mechanism has come to rest, said stitch-forming mechanism and work-holding means have a further relative movement by which they are shifted relatively from stitching position into buttonhole-cutting position, and after the buttonhole slit has been out said parts have an additional relative movement in the same direction to bring them into stopping position, in which position the machine as a whole is brought to rest.

In some buttonhole sewing machines the relative shifting movement between the stitch-forming mechanism and work-holding means by which the parts are shifted from stitching position to buttonhole-cutting position and then into stopping position, is one in which the needle has a forward movement relative to the workholding means during the entire shift from stitching position to stopping position, so that when the machine is finally brought to rest the needle is situated somewhat in front of the stitched buttonhole. Under these circumstances the operator has to use care in removing the work from the work-holding means after the completion of the buttonhole in order to avoid catching the work on the needle.

As stated aboveitis one of the objects of my present invention to provide a novel construction wherein when the sewing machine is brought to rest at the end of the button-hole cycle the relative position between the needle and the work-holding means will be one which is much more favorable for removing the work from the work-holding means or placing it therein without danger of catching the work on the needle, than in buttonhole sewing machines as previously constructed.

In accordance with my invention I provide novel means whereby when the sewing on the buttonhole has been completed the parts are not only shifted relatively from stitching position to buttonhole-cutting position in the usual manner, but after the buttonhole slit has been cut the stitch-forming mechanism and work-holding means are given a further relative movement in a reverse direction, or in the direction from buttonhole-cutting position back toward stitching position, and the machine is brought to rest during this return movement and preferably just before such relative movement brings the parts into stitching position.

With this arrangement the needle will be protected by the work clamps when they are raised so that there is very little danger that the work will be caught on the needle when it is removed from or being introduced into the work clamps.

In a buttonhole sewing machine embodying this invention the time interval required for completing any buttonhole sewing cycle is reduced because of the fact that the relative movement between the stitch-forming mechanism and. work-holding means from buttonhole-cutting position to stoppingposition is in a direction back toward stitching position instead of in a continued forward direction as in prior buttonhole sewing machines. Because of the fact that with this invention the relative movement from buttonhole-cutting position to stopping position is part of the relative movement from buttonhole-cutting position to stitching position the time required forthe completion of a buttonhole cycle is reduced even though the operation of the stitch-forming mechanism itself is not speeded up. 7 1

In the drawings wherein I have illustrated a selected embodiment of my invention, Fig. 1 is a side view of a buttonhole sewing machine having my improvements incorporated therein;

Fig. 2 is a section on substantially the line 22, Fig. 1;

Fig. 3.15 airagmentary view illustrating the portion 10 of the stitch frame. has the cam groove 14 in its upper face in which the The sewing machine herein illustrated is ofthat familiar type in which the work-holding means is carried on a work frame. and the stitchforming mechanism is carried on a stitch frame, said frames having a relative feeding movement during the stitching along the sides of the buttonhole and a further relative movement to carry the parts first from stitching position to buttonhole-cutting positionandthen from buttonhole-cutting position to stopping position.

The work frame is indicated at l and the work-holding means comprises the usual work clamps 2 pivoted to the work frame and co-operating with clamp plates 3 for clamping the work 4 in position. The stitch frame is indicated generally at 5 and it is provided with the usual stitch-forming mechanism which includes a vertically-reciprocating needle 6 operating above the work and-suitable looper mechanism or under thread mechanism carried by a turret 8 that is situated beneath the work and which carries the usual throat 9 through which the needle 6 operates, said turret being rotatively mounted in the portion 10 of the stitch frame which is situated beneath the work frame 1. The needle 6 is carried by the usual verticallyreciprocating needle bar 11 which may be operated in any usual way.

The movement of the'stitch frame on the bed frame or work frame isderived from the usual --main cam 12 which is mounted for rotation in a cam housing 13 that forms part of the under This cam 12 is received a stationary follower'15 carried by a stud 16 fixed in and depending from the bed frame 1. Since the stud 16 is stationary, rotation of the cam 12 will cause the stitch frame to move back andforth in thedirection of the length of the buttonhole as usual in buttonhole sewing machines of this type.

The main cam 12 is driven from a worm 17 which meshes with gear teeth on the periphery of the cam and which is mounted on a shaft 18 journalled in bearings in the stitch frame.-

19 indicates a driving pulley loosely mounted on the shaft 18, and when the machine is set in operation at the beginning of the buttonhole cycle this pulley 19 is clutched to the shaft 18 thereby to start rotative movement of the main cam. When the stitching on the buttonhole has been completed and during the movement of the stitch frame from stitching position to buttonhole-cutting position the rotation of the shaft 18 is also derived from the driving pulley 19 to which it is clutched, the stopping of the machine resulting from unclutching the pulley 19 from the shaft 18.

The clutch for clutching the pulley 19 to the main shaft is such as is usually employed in sewing machines of this type and it comprises a clutch dog 20 on the pulley 19 adapted to engage a clutch dog 21 on an'arm 22'fast to the shaft 18. The pulley 19 is'shiftable longitudinally of the shaft 18 to bring the clutch --dogs--20,--21into and out ofoperative "engageposition.

lever 32 is normally held inits operative posifront end of the lever 32.

ment and this clutching and unclutching movement is secured through the medium of a lever 22 pivoted at 23 to the cam housing 13 and having an arm 24 connected to a 'collar 25 that is received in a groove formed between two flanges 26 on a sleeve that is fast to the pulley 19. This construction is similar to that'shown in Patent No. 655,637, August 7, 1900, or in Patent No. 1,841,133, January 12, 1932.

It should be remarked that while the shaft 18 is driven from the driving pulley 19 at the beginning and ending of the buttonhole cycle, yet while the stitch-forming mechanism is operating to form stitches along the sides of the buttonhole the pulley 19 is disengaged from the shaft 18 and the latter is actuated from the shaft 50 which operates the stitch-forming mechanism and which is adapted to be clutched to or unclutched from the driving pulley 51, the construction being such that when the parts have been shifted from buttonhole-cutting position to stitching position the pulley 19 is disconnected from the shaft 18 and the pulley 51 is clutched to the shaft 50, thereby to start the stitch-forming mechanism in operation and when the sewing on the buttonhole has been completed, the pulley 51 is unclutched from the shaft 50 and the pulley 19 is again clutched to the shaft 18 thereby to cause the movement of the stitch frame from stitching position to buttonhole-cutting position. The unclutching of the pulley 19 from the shaft 18 and the clutching of the pulley 51 to the shaft 50 when the parts have moved from buttonhole-cutting opening 29 formed in the arm 30 extending from the clutch-controlling lever 22. When the threearmed lever moves clockwise in Fig. 7 such movement will cause the driving pulley 51 to be clutched to the shaft 50 and the movement of the arm 28 will act through the arm 30 of the clutch-controlling lever-to turn the latter in a direction to disengage the pulley 19 from the shaft 18. The operation of this three-armed lever and of the clutches is, the same as that shown in the above-mentioned patents to which reference may be had for a more detailed explanation thereof.

The' clutch-controlling lever 22 is acted on by a spring 31 which normally tends to swing it into position to cause the clutch dogs' 20 and 21 to be engaged. When the sewing machine is at rest the clutch-controlling lever 22 is retained in its inoperative position against the action of the spring 31 through the medium of a lever 32 pivoted at 33 to the under side of the Work frame 1, said lever carrying a stud 34 engaging a cam face 35 on the clutch-controlling lever 22 and holding said lever in its retracted When the machine is at rest the tionshown in Fig. 2 by the starting lever 36 which is pivotally mounted on the Work frame 1 at 53,,said starting lever having 2. depending extension 3'7 adapted to engage a finger 38-at the acted on by a pushing spring 39 which tends normally to swing it clockwise Fig. 2, Which The starting of. the machine is accomplished Said lever 32 is spring,'however,- is less powerful than the spring iii in the usual way by depressing the starting lever 36 which will remove the end 37 from engagement with the finger 38. This will unlock the lever 32 and the spring 31 will then act to swing the clutch-controlling lever 22 counterclockwise in Fig. 2 thereby clutching the pulley 19 to the shaft 18 through the medium of the clutch dogs and 21. This sets the machine in operation and the initial rotation of the cam 12 moves the stitch frame into stitching position. When the stiching position has been reached the stitch-forming mechanism is set in operation for stitching along the sides of the buttonhole, in the manner described in the above-mentioned patents, during which time the pulley 19 will be disengaged from the shaft 18 as will be readily understood. When the stitching has been completed the stitch-forming mechanism is brought to rest with the needle raised and the pulley 19 is again clutched to the shaft 18 to cause the parts to move from stitching position to buttonhole-cutting position, in which latter position the buttonhole slit is cut through the medium of the usual buttonhole cutter which is shown as mounted on a cutter arm 41 pivoted to the stitch frame at 42 and actuated at the proper time by a cutter cam projection 43 on the main cam 12.

When the stitching on the buttonhole ends the stitch-forming mechanism is in substantially the position shown in Fig. 3 and during the shift from stitching position to buttonhole-cutting position the stitch frame is moved forward to carry the needle somewhat in front of the work clamps as indicated in Fig. 4.

The machines shown in the above-mentioned patents are constructed so that after the stitch frame has been shifted forwardly from stitching position into buttonhole-cutting position and the buttonhole has been cut, said stitch frame is given further forward movement into stopping position and the driving pulley 19 is then unclutched from the shaft 18. This is illustrated in Fig. 1.

When the stitching on the buttonhole is completed the position of the stitch frame will he one which will give the needle a position indicated by the dotted line b in Fig. 1, this being the position at which the stitching on any buttonhole ceases and the position which the needle has when the stitching begins on the next buttonhole. The shift of the stitch frame from stitching position to buttonhole-cutting position will carry the needle from the dotted line position b to the dotted line position a. In the prior machines above referred to the additional movement of the stitch frame from buttonhole-cutting position to stopping position would carry the needle still further forward into a dotted line position indicated at 9 so that when said machines are brought to rest the needle will be in its extreme forward position somewhat in advance of the work clamps. When the machine comes to rest the work clamps are opened so that the operator can remove the work 4 or can shift the work into position to have a fresh buttonhole sewed therein. Where the machine stops with the stich-forming mechanism in the advance position shown by the dotted lines g in Fig. 1 the operator has to exercise care not to snag the work on the needle as he removes it from the clamp or replaces it therein.

In my present invention I have provided means whereby when the sewing on any buttonhole has been completed the stitch frame has its usual forward shifting movement from stitching position to buttonhole-cutting position or from the position indicated by the dotted line b Fig. 1 to that indicated by the dotted line a,

but instead of moving further forwardly into a stopping position after the buttonhole has been cut, the stitch frame is started on its reverse journey from the buttonhole-cutting position back toward stitching position and the machine is brought to rest during such reverse journey and with the stitch frame in substantially the full line position Fig. 1 or just before it arrives at stitching position. This operation of making the shift from buttonhole-cutting position to stopping position part of the return journey from buttonhole-cutting position to stitching position is secured partly through the shape of the cam groove 14 and partly through the medium of a specially-constructed clutch-disengaging cam carried by the clutch-controlling lever 22. The cam groove 14 is made so as to give the stitch frame not only its feeding movement for sewing along the sides of the buttonhole but also the movement from stitching position to buttonhole-cutting position and then back to stitching position again.

The specially-constructed clutch-disengaging cam is designed to disconnect the pulley 19 from the shaft 18 at the proper time in the reverse journey from buttonhole-cutting position toward stitching position. This cam is in the acted on by a spring 49 which normally tends to turn it into the position shown in Fig. 6.

It will be remembered that the stud 34 is carried by the lever 32 which is secured to the work frame 1 and hence has no movement in the direction of the length of the buttonhole,.while the clutch-controlling lever 22 with its cam member 44 are carried by the stitch frame. During the sewing along the sides of the buttonhole the follower 15 is operating in the portion j of the cam groove 14 and the stud 34 will be in front of the cam 44 as shown in Fig. 5. As the cam 12 continues its turning movement and the follower 15 passes through the portion 0 of the camgroove 14, the stitch frame is shifted forward from stitching position to buttonholecutting position and during this shifting movement the stud 34 wipes past the cam 44 and comes into the position shown in Fig. 6, the cam yielding or turning about its pivot to allow the stud to pass. When the stitch frame reaches the buttonhole-cutting position the follower 15 enters the concentric portion d of the cam groove and while it is travelling through said concentric portion the buttonhole slit is out. When the buttonhole slit has been cut the follower enters the portion e of the cam groove 14 and the stitch frame then begins its return'journey from its forward position in which the needle is in the position shown in Fig. 4 and in the dotted line position a in Fig. 1. starts its return journey the stud 34 engages the cam face 35 of the cam 44 thereby shifting the lever 22 downwardly in Fig.2 and disconnecting the pulley 19 from the shaft 18.

The final disconnection of the pulley from As the stitch frame thus mechanism.

the shaft occurs just before the stitch frame reaches stitching position so that the machine is brought to rest during the return movement of the stitchframe from buttonhole-cutting position to stitching position andjust before the stitching position is reached. This is the position illustrated in full lines in Fig. 1 and it will .be observed that in this position the needle is protected or guarded by theraised work clamp 2 so that the work can be freely removed from the clamps or placed therein without danger of becoming snagged on the needle.

Another advantage of the construction herein illustrated and which has been referred to above, is that it enables the operator to increase his production without any corresponding increase in the speed of. operation of the stitch-forming It has been explained above. how by means of thisinvcntion the movement of the stitch frame from buttonhole-cutting position forwardly into stopping position (represented by the dotted line position g in Fig. 1) and back to buttonhole-cutting position is eliminated.

In those sewing machines such as illustrated in above-mentioned Patents No. 655,63! and No. 1,841,133, when the machine is started in operation the stitch frame moves from its forward stopping position backwardly to buttonhole-cutting position and then still further backwardly :t0 stitching position, at which time the stitchforming mechanism is set in operation, and after the stitching on the buttonhole has been completed the stitch frame moves forwardly from stitching position to buttonhole-cutting position and subsequently has a further forward movement into stopping position. By eliminating this movement from buttonhole-cutting position forwardly into stopping position and by construct- 'ing the sewing machine so that the movement from buttonhole-cutting position to stopping position is part of the movement necessary to shift .the stitch frame from its buttonhole-cutting position to stitching position, the time interval re-' quired for completing the cycle of operations "is'reduced even assuming that there is no change in the actual speed of operation of the stitchforming mechanism. Therefore, with this invention an operator is able to increase his production even though there has been no increase in the speed of operation of the stitch-forming mechanism.

In buttonhole sewing machines of this type the clamps are opened to release'the work after the buttonhole slit has been cut and in the present invention this opening of the clamps occurs while the stitch frame is moving backward from its forward buttonhole-cutting posi- In removing the work from the clamps the natural tendency for the operator is to pull the work forwardly. At the time the clamps are opened, however, the needle is moving backwardly so that the needle and the work have relative movements in opposite directions and this also helps to prevent the work from becoming caught on the needle.

I claim: '1. A buttonhole sewing machine having stitching mechanism, work-holding means, buttonhole-cutting means, means operating during the making of each buttonhole to move the stitching mechanism and work-holding means relatively from stitching position to buttonholecutting position and back towards stitching position, and means to bring the machine to :rest during the relative movement from buttonholecutting position to stitching position.

2. A buttonhole sewing machine havin stitching mechanism, work-holding means, buttonhole-cutting means, means operating during the making of each buttonhole tomove the stitching mechanism relative to the work-holding -means from stitching position to buttonhole-cutting. position and back towards stitching position, and means to bring the machine to rest during the relative movementfrom buttonhole-cutting position to stitching position.

3. A buttonhole sewing machine having workholding means, a stitch frame carrying stitching mechanism, means tomove the stitch frame relatively to the work-holding means to carry said stitch frarnefrom stitching position to buttonhole-cutting position and return it, to stitching position, a buttonhole cutter to cut the buttonhole slit when the stitch frame is in buttonhole-cutting position, and means to bring the machine to rest during the movement of the stitch frame from buttonhole-cutting position to stitching position.

4. A buttonhole sewing machine having workholding means, a stitch frame carrying stitching mechanism, means to move the stitch frame relatively to the work-holding means to carry said stitch frame from stitching position to buttonhole-cutting position and return it to stitching position, a buttonhole cutter to cut the buttonhole slit when the stitch frame is in buttonhole-cutting position, and means to bring the machine to rest just before the stitch fram reaches sewing position.

5. A buttonhole sewing machine having workholding means, stitching mechanism, buttonhole-cutting mechanism, means to give the stitching mechanism and work-holding means a relative feeding movement during these'wing on the buttonhole and a further relative movement at the completion of the sewing to carry the parts from sewing position to buttonholecutting position and back to sewing position,

and means to bring the machine to rest during the relative movement from buttonhole-cutting position to sewing position.

6. A buttonhole sewing machine having stitching mechanism, work-holding means, means to give the stitching mechanism and work-holding means a relative feeding movement during the sewing on the buttonhole and after the stitching is completed a further relative movement first in a direction to separate the stitched buttonhole from the stitching mechanism and then in a reverse direction, and means to bring the machine to rest during the relative movement in said reverse direction.

7. A buttonhole sewing machine having stitching mechanism, work-holding means, meansto give the stitching mechanism afeeding movement relative tothe work-holding means while sewing along the sides of the buttonhole and after the sewing has been completed a further relative movement. first in a direction to separate the stitched buttonhole from the stitching mechanism and then in an opposite direction, and means to bring the machine to rest during such movement in said opposite direction.

8. A buttonhole sewing machine having a work frame carrying work-holding means, a stitch frame mounted for movement on the work frame, stitching mechanism carried by the stitching frame, means to give the stitch frame a feeding movement while sewing along the sides of the buttonhole and a further movement after the sewing is completed, first in a direction to separate the stitching mechanism from the stitched buttonhole and then in a reverse direction, and means to bring the machine to rest during the movement of the stitch frame in said reverse direction.

9. A buttonhole sewing machine having stitching mechanism, work-holding means, buttonhole-cutting means, means operating between the completion of the stitching on one buttonhole and the beginning of the stitching on the next buttonhole to move the stitching mechanism and work-holding means from stitching position to buttonhole-cutting position and back to stitching position again, and means to bring the machine to rest during the relative movement from buttonhole-cutting position to stitching position.

stitch frame from buttonhole-cutting position to stitching position.

11. A buttonhole sewing machine having stitching mechanism, work-holding means and. buttonhole-cutting means, said stitching mechanism and work-holding means being movable relative to each other and having one relative position while the buttonhole is being cut and another relative position while the stitching mechanism is operating, and means to bring the machine to rest between buttonhole-cutting position and stitching position.

JOSEPH H. PIKUL.

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