US2084838A - Sewing machine - Google Patents

Description

June 22, 1937. s. Ai-DOBYNE SEWING MACHINE Filed March 4, 1951 4 Sheets-Sheet 2 II/filin .FuneZZ, 1937. s. ApDOBYNE I SEWING MACHINE Filed Marn 4, 1951 4 Sheets-Sheet 3 6 57'EI/E/YS 04 A 005 MM,

3 6) wan June 22, 1937. s, A DOBYNE 2,034,838

SEWING MACHINE Filed March 4, 1931 4 Sheets-Sheet 4 Patented June 22, 1%3? tan SEWING Stevenson A. liiobyne, St. Louis, Me assignor to Champion Shoe Machinery (Company, St. Louis, Md, a corporation of Miss-card Application March it, 331, gcriai No. 519,933.

24 Claims.

This invention relates to sewing machines, and more particularly to a machine of the McKay type. Such a machine, as is well-known, is usually provided with a horn, the tip of which is provided with a whirl arranged to wrap the thread around a barbed needle. A presser foot feeding mechanism and thread measuring mechanism are provided in order to adapt the machine to different thicknesses of work.

Some of the objects of this invention are to provide novel presser foot operating mechanism, novel work feeding mechanism, novel needle operating mechanism, novel thread measuring mechanism, a novel needle gauge, a novel cast ofi, a horn construction, means for preventing the thread from coming into contact with the moving parts within the horn, and novel driving mech-= anism.

Another object is to improve the machine as to its construction and operation, so as to improve its emciency and render the same economical to manufacture.

Further objects will appear from the detail description taken in connection with the accompanying drawings, in which:

Figure 1 is a side elevation of a machine embodying this invention;

Figure 2 is an enlarged detail showing the presser foot operating mechanism;

Figure 3 is a section on the line 3-3, Figure 1, also of the presser foot mechanism;

Figure 4 is a section on the line fi-G, Figure 1, showing the feeding mechanism;

Figure 5 is a detail elevation of Figure 4;

Figure 6 is a further detail elevation of Figure 4;

Figure 7 is a detail front elevation of Figure 1, showing the needle operating mechanism;

Figure 8 is a detail side elevation of Figure '7;

Figure 9 is a detail section on the line 9--9 of 40 Figure 1;

Figure 10 is a section on the line Ill-ill of Figure 1, showing part of the mechanism in elevation;

Figure 11 is a section on the line H-i Figure 8;

Figures 12 and 13 are detail elevations showing the needle gauge;

Figure 14 is a detail of the horn bracket;

Figure 15 is a longitudinal vertical section through the horn;

Figure 16 is a section on the line lS-JG, Figure 15;

Figure 17 is a side elevation of the motor sup- 55 port;

(433i. MMQ) Figure 18 is an enlarged vertical section showing the driving mechanism;

Figure 19 is an enlarged section of the clutch and brake at the top of the machine head; and

Figure 201s a detail of Figure 19.

Referring to Figure 1, i designates a base on which is mounted a column 2 and on which in turn is mounted a machine head '3, having a base d, provided with hearing brackets it? and tilt, and carrying a shaft The horn is generally shown at 6.

Presser foot apemting mechanism Referring to Figures 1, 2, 3, and 7, guided tor vertical'movement in the machine head is a presser foot bar it, having at its lower end a presser foot ill. The presser foot bar has a guideway slidably engaged by a .block 52, on an arm it, fixed to a shaft Mi, journalled in bracket tilt. A spring i5 encircles shaft i l and is connected at one end with the shaft with its other end bearing against the base l of the head, so as to normally tend to move the presser foot down. The lower position of the presser foot is determined by an adjustable set screw it at the end or the arm iii, engaging the base '5.

Fixed to the shaft i5 is an arm i'i carrying ratchet teeth It, which are inclined, as shown. Loosely mounted on the shaft M is an arm 19 provided with a cam roll 28, engaging a cam 2! on the shaft 5. Pivoted on a lateral extension 22, formed on or fixed to the arm 19, are a series of levers 23, having pawls 25., arranged to engage the ratchet and held thereagainst by plungers 25, guided in the extension 22 and under the action of springs 26. The other ends of the levers are provided with rolls 2?, engaging a cam 26 arranged along side of the cam 2| and also fixed to the shaft 5.

Fixed to the arm 59 is an arm 29, perforated to pass loosely over a shank 36, mounted on the base i and encircled by a spring 3|, bearing at one end against a washer over the arm 29 and at its other end against a washer tensioned by a nut 32. Threaded into the end of the arm 29 is an adjustable abutment 33 arranged to bear against stops in the form of leather washers 34. The arm I? has fixed thereto an arm 35, perforated or forked to receive the upper end of a bar 36 provided with a washer and a nut 31,. and connected at its lower end with a treadle 38, pivoted in the base I and held in raised position by a spring 39.

The mechanism described and shown Operates to intermittently raise the presser foot a predetermined distance during the operation of the machine and while the work is being fed, and thereafter to release it in order to not only clamp the work against the horn, but also to provide an abutment or support while the stitch is being set. As previously stated, the spring operates to hold the presser foot in its lowest position determined, however, by the adjustment of the set screw l6. Assuming the pawls 2% be in a position to engage the ratchet teeth l8 under the tension of the springs 26, the cam M will operate to move the arms l9 and i1 clockwise; Figure 3, so as to'raise the presser foot a definite amount in order to permit the work to be fed. The pawl is, however, disengaged by the cam 28 in order to release the presser foot so as to enable it to accommodate itself to the work. Upon release of the arm l9, it will be returned by its spring 3| with the abutment 33 striking against the bumpers 34 and the position of this arm and, accordingly, the position of the pawl with reference to the ratchet teeth can be controlled by adjustment of this abutment for the arm, it being understood that the position of the lever H is determined by set screw it. Now, at the time that the stitch is set, the work is raised from the surface of the horn tip and it must be supported at that time in an upward direction by the presser foot. Usually a locking device is employed to lock the presser foot at this period. In accordance with this invention, however, the springs 26 are made strong enough and the angle of the ratchet teeth is such that there will be interposed a sufficient resistance against the raising of th presser foot'duiing the setting of the stitch, so that a separate locking device can be eliminated. It will be understood that the presser foot may be raised at any time by the depression of the treadle 38 which acts through the arm 35 to rotate shaft M.

The sequence of operations in forming the stitch is as follows; the needle having penetrated the work and engaged the thread is raised out of the work. The presser foot H, is then lifted. At the same time, or slightly before, the feed point 41 engages the work and is moved laterally to feed the work. During the interval that the presser foot is raised the needle reaches the top of its stroke and exerts a pull on the thread. This is an upward pull on the thread and effects preliminary setting of the stitch and at the same time measures a length of thread for the. next stitch. This pull forces the work upwardly against the presser foot which is supported by the pawl 24, as described above. The needle pauses at the top of the stroke and during this pause the cam 28, releases the presser foot which drops down upon the work, forcing it against the horn and at the same time giving the thread the final pull to finally set the stitch. As soon as the presser foot II, has been released to re engage the work the needle descends again making the succeeding stitch. In accordance with this invention, therefore, the pawl and ratchet of the mechanism is constructed and engages to sustain the presser foot during the'setting of the stitch; these elements being relatively tensioned to prevent retrograde movement of these elements. A cam is provided for moving the ratchet and pawl while engaged, while a separate cam is provided for disengaging the pawl from the ratchet.

Feeding mechanism Refen'ing to Figures 1, 3, 4, 5, and 6, attached to the presser foot is a guide cam 40, having an inclined guiding portion M and a horizontal guiding portion 42. Travelling in this guide is a roll as, mounted on a lever 44, having a fork 45,

pivoted and sliding on a stud 46 on the presser foot bar Ill. The other end of .the lever carries a feed point 47, arranged to lie within the grooved end of the presser foot, while the lever 54 is positioned by a stop 48 on the presser foot bar.

The lever 44 is connected by a link 49 with an arm 50 on a shaft 5|, mounted in a suitable bearing on the base 4, and having an arm 52 provided with cam rolls 53 and 54, engaging cams 55 and 56, fixed to the shaft 5. A spring 51 encircling the shaft 5| moves the rolls toward the cams and tends to hold the lever 46 in engagement with the stop 48. The roll 53 is fixed in position on the arm 52; however, the roll 55 is eccentrically mounted on a short shaft 58 in the arm, which is provided with a head 59 engageable by a wrench, so the position of the roll may be adjusted on the arm towards and from the cam 56. The arm is split, as shown at fill, and provided with a clamping screw, so that the shaft 58 may be locked as adjusted.

The connection between the lever 46 and the link 59, Figure 6, comprises a shank 6| on which is mounted the roll 43, while a washer 62 bears against the guide 40. The link 49 is provided with a bushing 63, while a spring 64 bears at one end against a head 65 on the shank and at its other end against the link 49. The construction is such as to take up all play while permitting sliding of the cam roll in the guide to perform its function. I

In the operation of feeding, it will be noted that there is imparted to the feed point first a piercing movement while the roll 43 moves down the inclined part 4| of the guide, and thereafter a feeding movement while this roll moves along the horizontal part of the guide. Now, the work piercing movement must be constant irrespective of the length of the stitch, while the feeding movement must be variable in accordance with the length of the stitch. In accordance with this invention, these movements are accomplished through the medium of two cams 55 and 56, operating on two rolls 53 and 54, mounted, however, on a single arm 52. Since the piercing movement should be invariable, the roll-53 need not be adjustably mounted on its arm. In order, however, to secure anadjustable feed, the roll 54 is mounted for adjustment on its arm towards and from its cam, so as to St. :ure either minimum, maximum, or any intermediate movement; it being noted that the position of the lever M is determined by the stop 48. By, therefore, adjusting the roll 54, the idle movement between the cam 56 and the cam roll 54 can be adjusted to suit requirements.

In accordance with this invention, therefore, a work feeding element 41 is connected with an actuated element 52 for moving the same, and actuators in the form of cams 55 and 5B cooperate with the actuated element to impart thereto work penetrating and feeding movements; while means is provided for adjusting cooperation of one of these actuators with the actuated element by adjusting the point of engagement of that element with one of these cams. The support provided by the presser foot bar has a guide 40, while an element 66 pivoted on that support has a part 43 movable along this guide; this guide being shaped to impart work penetrating and work feeding movements to this point.

D ostess Needle operating mechanism Referring to Figures 1, 7, 8, and 11, a needle bar 66 is guided for vertical movement in suitable hearings in the head 3 and carries at its lower end a hooked needle 61 arranged to cooperate with a whirl within the horn tip. This needle bar has a. cross head 68 within which slides a block 69 on one arm of a bell crank lever it, the other arm of which is pivoted on an arm ll, fixed to the shaft 5 and provided with a counter-balance 72. The intermediate point of the bell crank lever has a roll it engaging a cam groove id in a cam plate 115, pivoted at it on the head 3. A spring ill encircles a plunger it, slidable in a lug it on the head 3 and engages against a nut 88 on the plunger bearing against a shoulder 85 on the cam plate it, so as to normally hold a lug 82 on the cam plate against a stop 93 on the head 3.

Rotation of the shaft 5 will carry the arm ii and the bell crank lever ill with it, so as to reciprocate'the needle bar. The cam id is, however, so constructed that the needle bar and its needle will be at rest at the upper and lower limit of travel during a considerable arc of movement of the shaft 5. There will thus be a pause at the upward stroke to allow the presser foot to force the shoe down on the horn tip and thus assist in setting the stitch while the needle is stationary; and there will be a pause at the bottom of the stroke to allow the whirl to rotate around the needle while its bar is again stationary. With this construction the needle stops and starts without shock. The counter weight it serves to balance the arm ii and the bell crank lever iii, so as to facilitate smoothness of operation and to avoid vibration.

in accordance with this invention, the fastener inserting element, which in this particular machine is in the form of a needle, has actuating mechanism including a crank ii and means operating to cause the fastener inserting element to pause at the end of its travel. This means is intermediate the crank and the element, and is in the form of a connection between the crank and the element together with a controlling device adapted to vary the operation of the fastener in serting element by the crank. The connection between the crank and the element is in the form of a lever id, pivoted to the crank and having a sliding connection with the element, while the controlling of the connection is secured by a cam it engaging this lever.

It will be noted that the crank it together with the arm iii forms a compound crank whose crank pin moves at a variable eccentricity with reference to the shaft 5. was eccentricity is controlled by the cam l6.

Thread measuring mechanism In a machine of this type, the needle is used to measure the thread for varying thicknesses of work. This is accomplished in accordance with this invention by varying the upward stroke of the needle in accordance with the thickness of the work, while the lower position of the. needle is maintained constant in order that the needle may always be in the correct position to permit the whirl to wrap the thread into the barb. Mechanism is, therefore, provided for imparting a variable stroke to the needle in its upward position only.

Referring to Figures 1, l, 8, 9, and 10, the cam plate l5 has attached thereto a hardened plate 8%, positioned opposite a similar hardened plate to the shaft 5.

has fixed thereto an arm 88 provided with a roll 89 engaging a cam 90 in a cam wheel ti on the shaft 5. Between these two hardened plates is arranged to slide a block 92 connected by a link 93 with an arm 94 pivoted on a stub shaft 95 on the base d. This shaft'also has a toothed part 96, cooperating with a corresponding toothed part 9i on the block 52, mounted on the arm l3. The toothed part 96 has an arm 93 lying over the arm 94. A spring 99 encircles the shaft 95 and connects the arms 96 and 98 yieldingly, so as to normally hold them in engagement while permitting yield therebetween.

The joint between the arm 9d and the link 93 is formed by an eccentric lllii, (see Fig. 8) the shank of which is mounted in the arm fi l and is provided with a knurled head ml to permit adjustment. The end of the arm 9% is split and provided with a clamping screw 12. The cam roll 89 is also mounted eccentrically in the arm 88 and adjustable by a knurled head IE3, while the end of the arm is again split and provided with a clamping screw i 3. As seen in Figure 9, the shaft has a nib W5 workingin a recess M16 in the cam plate 15.

It will be seen that the block 92 is interconnected with the presser foot so as to move to the a left, Figure 10, as the presser foot is raised in accordance with the thickness of the work. In

' doing so, it moves away from the pivots l6 and whose position is determined by the thickness of the work. Let us assume now that the presser foot has been raised by the work so as to position the block 92 between the plates 86 and 85. During the down stroke of the needle the cam 9d will be inactive so as to not shift the cam plate with the result that the same is not positioned by the stops 82 and 63, so that the needle will move to the predetermined and fixed lower limit of its travel. During the up stroke of the needle, however, the cam 90 will come into play so as to move the arm 86 clockwise or upwardly thereby shifting the cam plate 15, in order to cause the needle at its upper limit to assume a, position in accordance with the thickness of the work in order to measure out thread corresponding to that thickness. During the down stroke of the needle, however, the arm til will again move back so that the needle can again reach the fixed lower limit of its travel. In order to insure this action, the nib its is so positioned that as the needle moves down, the nib will move in the recess so as to positively return thecam plate iii against the stop 83 thereby supplementing the action of the spring ill.

it will be noted that the arrangement shown in Figure 11 provides that by cooperation be-= tween the cam i l and the bell crank 76 the needle bar is actuated by the roll es in the same manner as if this werea crank on the shaft 5, except that the length of the crank arm is variable during a revolution so as to provide a pause at the upper and lower ends of the stroke of the needle bar.

The efiect of shifting the cam plate '15 on its pivot 16 is to elevate the cam it with reference This movement of the cam will have the efiect of lengthening the up stroke and shortening the down stroke of the needle bar. In other words the range of movement of the needle bar is shifted upwardly with reference to aosasaa the shaft 5. Now the mechanism illustrated in Figure 10 is designed to accomplish the shift of the cam plate 15 to efiect this result. In its normal position the slide block 92 is substantiallly in alinement with the pivot 81 of the arms 8% and 88. In this position of the slide block 92 the efiect of the cam will be simply to rock the arm 85 upwardly at a certain point of each revolution. This will have no eifect on the plate at or the cam plate l5 because the block 92 is still in alinement with the pivot 87. When, however, the presser foot is raised above its normal position by an extra thickness of the work, the plate 52 is elevated and this acts to rotate the shaft which in turn acts to shift the slide block 92 to the left, Figure 10, along the plate es. With the slide block 92 in its shifted position it is displaced from alinement with the pivot 8i and will now partake of the elevating movement of the plate 85' and transmit the same to the plate 86 and the cam plate '15. This elevating movement occurs during each up stroke of the needle bar, while the plate 85 is returned to its normal position on the down stroke of the needle bar. It will be seen, therefore, that the efiect of this action is to lengthen the up stroke of the needle bar, while the down stroke is retained constant. The amount of change of the up stroke is proportional to the shift of the slide block Q2 which in turn is proportional to the excess thickness of the work.

It has been noted that the arms 9d and 9d are connected yieldingly through the spring as. This permits the presser foot to raise at the proper time in the cycle of operations even if the cam 90 should be active at that time to cause the block 921:0 become gripped between the plates 8 3 and 85; for the spring 99 will yield at that time, while as soon as the pressure has been relieved, the block 92 can slide to its required position. In order to adjust the machine for special work requiring extra long stitches, the head sea is turned so as to shift the block 92, in order to cause the upper limit of the needle stroke to be increased while thereafter the increase will be in accordance with the thickness of the work. The adjustment of the knurled head I03 provides an extra means for initially adjusting the machine, or in order to suit conditions which may be encountered.

In accordance with this invention, therefore, where the needle operates to measure the thread required, a work engaging element, such as: the

presser foot, has cooperating therewith mecha= nism controlled by that element for adjusting the retracting stroke of the needle, particularly where the needle cooperates with the horn provided with the whirl. The needle or fastener inserting element is moved by an actuator ll through a connection it, while means is provided, controlled by the work engaging element, adapted to control that connection to vary the retracting stroke of the fastener inserting element. This mechanism includes an operator 86-33, a connector Q2 adjustable by the work engaging element relative the operator, and means for controlling the actuating mechanism from the connector. Also included in the line of connections is the shiftable cam plate 15, which is shifted bythe mechanism is also provided for adjusting the connection be-- tween the work engaging element and. the connectar.

Needle gauge and cast 01? Referring to Figures 12 and 13, Ill! designates a needle gauge which is pivoted on a shank I08 on a lug 509 on the base 5. It is held in adjusted position by a set screw lid and frictionally by a spring ill encircling the shank. With this construction not only is the needle gauge positioned, but it may be moved out of the way and held frictionally in that position while the set screw I It provides means for accurately adjusting its position with respect to the needle.

Referring to Figures 7 and 8, the cast off i i2 is guided in the needle bar $6 and has at its top a block'i i3 enga a slot lid in a slide M5 guided in a cross head 68 and the top guide of the needle bar. Between this block and slide is a spring I it. The slide M5 is guided between opposite gibs 1, one of which is engaged by a spring pressed plunger M8. The operation-of this cast off will be obvious from the above description; the slot Md provides for limited movement of the cast 01f with respect to the slide H5, while the latter is frictionally held by the spring pressed plunger i l 8.

Horn construction which is arranged so that it may be positioned against and bolted to the machined face of a similar web EEG. and H23 for a shaft'i2 l, provided with bevel gears Ti 25 and H26. Arranged in this bracket is a socket in which is arranged to be positioned a shank I21 of a. bearing M8 for a vertical shaft 929, pro- This bracket has bearings H2 vided with a bevel gear ltd arranged to mesh with the gear ltd. The bearing B28 is arranged to be clamped in position by a set screw l3i. A guard M2 is clamped on the bracket by screws I33.

The shaft are extends upwardly and is provided with a bevel gear ltd meshing with a bevel gear 935 on the shaft 5. The bevel gear-I meshes with a bevel gear 936 fixed to a hollow shaft i311 extending .through the horn and provided at its top with a bevel gear 838. The gear E38 meshes with a gear E39 on a shaft Mb provided at its other end with a gear Mil meshing with'a gear M2 on a shaft M3 coupled with a shaft we provided with a gear M5 meshing with a gear M6 on the whirl id? in the horn tip.

The shaft it? is guided in the horn spindle its which is mounted on roller bearings M9. This spindle is in turn mounted in the horn bearing bracket B50 bolted against the flange i2d of the bracket Mb. Mounted on the horn spindle M8 is a base lei for the horn t. A lubricating duct E52 provides for the emission of oil to the horn spindle. Arranged within the horn are rollers 853 over which the thread passes. A cover 95d pivoted at E55 is provided with a latching device it controlled by a knurled head lfi'l. The cover along the horn tip is provided with a groove 58 to permit passage of the thread therethrough, and a plate B59 keeps the thread out of contact with the coupled shaft sections M3 and Me.

Driving mechanism Referring'to Figures 1 and 17 to 20 inclusive, the column 2 has pivoted thereon a bracket 200, on which is mounted a motor Edi. This bracket has hinged thereto at its outer end a bar 202 eaded into a hand-wheel 2693, whose end has 229, loose on the shaft 5.

a ball and socket connection with 2. lug 26 on the column. The motor has a pulley 25 connected by a belt 206 with a pulley 201. By rotation of the hand-wheel 203 the belt may be tightened and loosened, as desired. The handwheel can be entirely disengaged from its socket so as to permit the bracket 200 to drop against the side of the column in order to conserve space during shipment.

Referring now to Figures 1 and 18, the pulley 201 is loosely mounted on a shaft 208 fixed in the base I. Opposed to this pulley is a fly-wheel 209 having an extended hub 2| 0, which also.forms the hub of a belt pulley 2. Suitable thrust. bearings M2 and M3 are provided. Bearing against the thrust bearing and arranged to slide on a, shaft 268 is a collar 2M1, connected with a fork 2l5 of the bell crank lever, pivoted on a bracket 2l6 secured to the'shaft 208. The other arm 2E8 of the bell crank lever is connected by an adjustable link 2!!! to a treadle 220 mounted on a bracket 22!, (on which is also mounted the treadle 38). The brackets 2H5 and 226 are connected by an adjustable strut 222. The face of the pulley 281 is machined, while the face of the fly-wheel is provided with suitable inserts 223 of leather or the like. Imposed between the pulley and the fly-wheel are springs 226i engaging a thrust ring 225 of suitable antifriction material, such as graphite compositions, and which bears against the hub on the flywheel. The shaft 2% is provided with a groove 226 adapted to receive a suitable packing while a lubricant cup 22? connects with this groove. The treadle 22 is held raised by a spring 3%.

The fiy-wheel 229 is normally held disengaged from the pulley 2W by the springs 226, so that this fiy-wheel will be at rest. Upon depression of the treadle 22h, howeventhis thy-wheel is caused to engage the pulley so as to movethere with. Now, this fiy-wheel will accumulate energy as it has considerable inertia. It will also be noted that the ratio of leverage between the lever arm ofthe treadle to the left of its pivot, Figure 22, is high as compared to the leverage to the right of its pivot. This enables a slow engagement and disengagement to be secured; accordingly, by slowly engaging the fly-wheel with the pulley, not only is this fly-wheel ena bled to pick up speed slowly, but on account of the high ratio of leverage, previously referred to, any desired slip maybe secured, so that the flywheel may he driven-at a variable speed on account'cf slippage. its this fly-wheel stores en-= ergy, even after the treadle is released, the stored energy will insure that the operations of the mechanism driven by the pulley 2M will be completed.

Referring now to Figures 1, i9 and 2c, the pul= ley tilt is connected by a belt 226 with a pulley This p ey has cone fccebcoperating with the faced cone of a double cone element splined on the shaft 5. The other cone element 236 cooperates with a. ccrre= spending cone 2532 providing a bramng surface. The hub 238 of cone 232 extends through a bearinc 2% and in turn provides a hearing for the shaft 5.

The pulley 22s is mounted on a bushing 235 on the shaft 5, and this bushing is provided with a flange 22$, carrying springs 23'? bearing against the cone element 232. A ring 238-021 the hub of the pulley 229 bears against a shoulder on the hub 235. A washer 232 on the shaft has bearing thereagainst a cup 2% through which passes a stud 22! provided with nuts 222 and 243. A spring 262 engaging the cone element 23I bears against a thrust ring 225, which in turn bears against a ring 246 seated in a groove on the shaft 5.

The cone element 23] is provided with a wedged lug 2 31, while passing through the cone element 230 and attached to the flange 236 is an abutment 228' having a ground face and positioned approximate the wedge 241. A clutch shifter 249 is provided with a wedged tip arranged to engage the wedge 2'37 while the opposite face of the shifter is arranged to bear against the abutment 2 58, the tip of which is rounded. This clutch shifter is in the form of a bell crank lever pivoted at 250 on the head 3 and connected by an adjustable link 25! with a similar bell crank lever 252 pivoted on the column 2 and connected by a link 253 with the treadle 220. A spring 256 on the bell crank lever 252 operates to throw the shifter into disengaging position.

The brake element 232 is provided with a lug 255, arranged to ride between lugs 256 on the bracket of the bearing 232. Each of these lugs 256 is provided with a suitable bumper 251. The brake element 232 is provided with an arcuate slot through which passes a screw 258 threaded into the bearing bracket 232.

When the clutch shifter 249 is disengaged from the wedge 2447, the spring 24 3, (which is stronger than the spring 231), will move the cone 230 into engagement with the pulley 229, while the cone 23f will be moved out of engagement with the clutch surface 232, thereby connecting the pulley 229 with the shaft 5. When the clutch shifter is released, it will move into the path of the wedge 23?, thereby moving the connected cones back so as to disengage the cone 236 from the pulley and engage the cone 23| to the brake element 232, in order to bring the shaft to rest in a predetermined position.

It will be seen that this clutch shifter will be engaged on its opposite side by the abutment 2 38, which sustains the shifter against lateral movement. By adjustment of the nuts 242 and 2 33, this abutment may be shifted to take up for wear or provide for initial adjustment.

As previously described, the brake element 232 is not fixed, but is permitted limited rotative movement. Now, upon engagement of the cone 230 with the brake element, the latter will move therewith, so as to cause the lug 255 to strike against the lower bumper 25?. This striking actlon will cause the lug 255 to rebound until again arrested by the upper bumper. This is an advantageous feature for the following reason. If

the brake element 232 were rigid, the wedge 2 52 would become so firmly wedged against the clutch shifter as to render the disengagement of the clutch shifter difiicult. The rebound provided, however. causes the brake element 232 to move backwards thereby slightly disengaging the wedge 26? from the clutch shifter, so that the latter will be substantially free, and this after the rotation of the shaft has stopped. On account of the inertia of the parts, it is only necestop shaft with the variable speed friction clutch,

including a fly-wheel, provide means whereby the operations may be controlled, but particularly so in performing the operations for which the machine is designed. In sewing around the toe of a shoe, (particularly in repair work), it is desirable that the operator be enabled to slow down the machine so that he may keep the stitching in the groove or channel provided in the outsole. It is also necessary to slow down the machine when sewing along the shank of a high arched ladys shoe, and particularly as the stitching is finished along the shank. Now, it usually happens that just previous to stopping the machine, it is running at a very low rate of speed; accordingly, if the operator takes his foot ofi of the clutch pedal when the stitch is only partially completed, the complete stoppage would not secure the finished work. In accordance with this invention, however, momentum is stored in the fiy-wheel so that the stitching mechanism shaft will continue to revolve and complete the stitch. While there is a rebound, as previously described, this rebound is not sufficient to disturb the final position of the parts; accordingly, the machine is stopped with the parts in the position where the stitch has been fully completed.

While certain features of this invention are particularly applicable to a wax thread sewing machine of the McKay type, it will be understood that certain features are applicable to other forms and types of sewing machines and other forms and types of fastener inserting machines. It will furthermore be understood that certain features and sub-combinations are of utility and may be employed without reference to other features and sub-combinations: that is contemplated by and is within the scope of the appended claims. It is furthermore to be understood that various changes may be made in details, within the scope of the appended claims, without departing from the spirit of this invention. It is, therefore, to be understood that this invention is not to be limited to the specific details shown and/or described.

Having thus described the invention what is claimed is:

1. A sewing machine comprising, a presser foot, pawl and ratchet mechanism, and means actuating said mechanism to raise the presser foot, the pawl and ratchet of said mechanism being constructed and arranged to sust. the raised presser foot against the pressure of the work thereon during the setting of the stitch.

2. A sewing machine comprising, a presser foot, pawl and ratchet mechanism, and means actuating said mechanism to raise the presser foot, the pawl and ratchet of said mechanism being constructed and relatively tensioned to prevent relative movement of said presser foot in a direction to raise the presser foot during the setting of the stitch.

3. A sewing machine comprising, a presser foot, and mechanism for raising the mu cluding a pawl, a ratchet engaged thereby and a spring for engaging said pawl, said spring having suflicient tension to prevent relative movement of said pawl-and said ratchet in a direction to raise the presser foot during the setting of the stitch. I

4. A sewing machine comprising, a presser foot, and mechanism for raising the same including a pawl, a ratchet engaged thereby and means for disengaging said pawl from said ratchet, said pawl and ratchet being relatively tensioned to prevent relative movement thereof in a direction to raise the presser foot during the setting of the stitch.

5. A sewing machine comprising, a presser foot, and mechanism for raising the same including a pawl, a ratchet engaged thereby, a cam for moving said pawl and ratchet collectively while engaged, and a cam for disengaging said pawl from said ratchet to limit such movement.

6. In a sewing machine, work feeding mechanism comprising, an actuated element, actuating cams cooperating successively with said element, and means variable to adjust the cooperation of one of said cams with said element.

'7. In a sewing machine, work feeding mechanism comprising, an actuated element, cams ccoperating'with said element, and means for adjusting the point of engagement of said element with one of said cams.

8. A machine of the class described comprising, a fastener inserting element, and actuating mechanism therefor including, a crank, a. member carried thereby having a crank pin enga ing said element, and means controlling the relation between said crank and said member adapted to cause said element to pause at the end of its travel.

9. A machine of the class described comprising, a fastener inserting element, a crank, a connection member between said crank and said element, and a cam controlling said connection member adapted to vary the operation of said element by said crank.

10. A machine of the class described comprising, a fastener inserting element, acrank, a lever pivoted to said crank and having a sliding connection with said element, and a cam engaging said lever.-

11. A machine of the character described comprising, a fastener inserting element, an actuator 7 for shifting said cam.

13. A machine of the character described comprising, a fastener inserting element, a crank, a connection between said crank and said element, a cam for controlling said connection, an operating element, a work engaging element, and a connector between said operating element and said cam and adjustable by said work engaging ele- 4 ment. 1

14. A machine of the character described comprising, a fastener inserting element, a crank, a connection between said crank and said element. a cam for controlling said connection, means for shifting said cam, and means for positively returning said cam.

15. A sewing machine having a needle, a needle gauge, means for yieldingly mounting said gauge for movement to operative and inoperative M tlons, and means for adjusting the location of said gauge in operative position.

. 16. A sewing machine having a needle bar, a

cast-ofi' guided for movement on said bar, a slide yieldingly connected with said cast-ofl', and

means for frictionally retaining said slide.

aoeaeaa and releasable from said first mechanism upon stopping.

18. A machine of the class described comprising, fastener inserting mechanism, a clutch adapted to stop said mechanism at the completion of the fastener inserting operation, and driving mechanism including a driving element and a driven element engageable frictionally with said driving element to secure a variable speed, said driven element being of high inertia to accumulate energy to insure completion of the fastener inserting operation and releasable from said first mechanism upon stopping.

19. In a machine of the character described, a needle bar, operating means therefor, a workengaging element, separately actuated retracting mechanism adapted to control said operating means during retraction of said needle bar, and a variable connection between said retracting mechanism and said operating means controlled by said element.

20. In a machine of the character described, a needle bar, operating means therefor, a workengaging element, separately actuated retracting mechanism having a constant cycle of operation adapted to control said operating means during retraction of said needle bar, and a variable connection between said retracting mechanism and said operating means controlled by said element.

21. In a machine of the class described, a fastener-inserting element, and actuating mechanism therefor including a rotating drive shaft, a compound crank having a crank pin rotating with said shaft and engaging said element, and means operating to vary the eccentricity of said pin so as to cause said element to vary its rate of movement.

22. In a machine of the class described, a fastener-inserting element, and actuating mechanism therefor including a rotating drive shaft, 2.

compound crank having a crank pin rotating with said shaft and engaging said element, and means operating to vary the eccentricity of said pin so as to cause said element to pause at the end of its travel.-

23. In a machine of the class described, a fastener-inserting element, and actuating mechanism therefor including a rotating drive shaft, a compound crank having a crank pin rotating with said shaft and engaging said element, and a camcontrolled connection between said shaft and said pin operating to vary the eccentricity of said pin so as to cause said element to vary its rate of movement.

24. In a machine of the class described, a fastener-inserting element, and actuating mechanism therefor including a rotating drive shaft, a compound crank having a crank pin rotating with said shaft and engaging said element, and a camcontrolled connection between said shaft and said pin operating to vary the eccentricity of said pin so as to cause said element to pause at the end of its travel.

STEVENSON A. DOBYNE.

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