US2157370A - Feeding mechanism for sewing machines - Google Patents

Description

May 9, 1939. J. P. WEIS FEEDING MECHANISM FOR SEWING MACHINES Filed June 21, 1935 7 Sheets-Sheet l WEN INVENT OR John P W s W RS A ORNEY no I May 9, 1939. ,J. P. WEIS FEEDING MECHANISM FOR SEWING MACHINES vsheets sheet 2 Filed June 21, 1935 INVENTOR BY \hlolm W815 ATTORNYWM J. P. WEIS May 9, 1939,

HANISM FOR SEWING MACHINES FEEDING MEG Filed June 21, 1955 7 Sheets-Sheet 3 /88' Flea S JohnPWels LSZSLM l ATTO 2W a u 4 l ma 7 w m n 4 {A MW um {w a 7 m ,m D l M 6 u 6 ,7 N I lr U 3 w 1 J 6 0 6 p 5 9 M 4 May 9, 1939. I J. P. WEIS 2,157,370 FEEDING MECHANISM FOR SEWING MACHINES Filed June 21, 1935 '7 Sheets-Sheet 4 'IIII/ll "I'IZIIIIIIIIIIIIA 4 John P Mus WLQMS ATTORNEW ay 9, 1939- J. P. WEIS 2,157,370

FEEDING MECHANISM FOR SEWING MACHINES Filed June 21, 1935 7 Sheets-Sheet 5 354 INVENTOR John PWels 24s wfm A TTORNEY y 9, 1939- J. P. was 2,157,370

FEEDING MECHANISM FOR SEWING MACHINES Filed June 21, 1955 7 Sheets-Sheet 6 Patented May 9, 1939 UNITED STATES:

PATENT OFFICE FEEDING MECHANISM FOR SEWING MACHINES Application June 21, 1935, Serial No. 27,773 21 Claims. ((31.112-209) mechanisms, and especially to those of the type commonly known as a differential feed, su'ch feeding mechanism being provided with two feed dogs or work engaging elements each actuated either wholly or partially independently of the other to effect stretching, shirring, or pleating, and the invention consists in peculiar constructions and combinations hereinafter pointed out and claimed.

Sewing machines, especially those of the overseaming type, are often provided with a differential feed when the machinesare used on knit V goods or other material liable to stretch or pucker at its edge. The differential feed is designed to obviate the stretching effect, and is arranged to cause one feed dog (located in advance of the needle) to feed the goods up to the needle or point of overseaming, faster than the said goods are fed away from the needle by a second feed dog (arranged to operate in rear of the needle) and thus the goods are slightly condensed or gathered at the edge, nearthe point of overseaming.

It is a particular object of this invention to provide a very efficient mechanism for such gathering of material, and to effectively shir and pleat materials.

With certain classes of work it is desirable to stretch the materials at the time the seam is formed, and it is an object of the present invention to provide an efficient mechanism to effect such stretching.

In meeting this object the present invention provides a differential feed mechanism having a single mechanism which may be easily and quickly changed from a one-to-one feed to a threeto-one or other greater ratios of feed, and which may be changed to less than a one-to-one feed to effect stretching of materials.

With many differential feed mechanisms it is necessary to stop the sewing machine in order to obtain a different extent of feed, thus slowing production and causing inconvenience.

It is an object of the present invention to provide a feeding mechanism which may be varied easily'and quickly while the sewing machine is operating and regardless of the speed.

It is an object of the present invention to provide a machine with only one drive shaft, which: a

may be made in substantially one piece; will be sturdy, well balanced, thoroughly lubricated; will be free of vibration, wear, and end play; has a minimum number of eccentrics so that the machine may be small.

In meeting this object the present invention provides only one main. drive shaft with only one eccentric adapted to lift'both a primary and a secondary feed dog, and only one other eccentric adapted to. impart various extents of longitudinal or work carrying travel to both of these feed dogs.

It is another object of the present invention to provide feeding mechanism for a sewing machine which will be capable of operating at very high speeds with ease and quietness, and with minimum vibration and wear.

Special feeding problems are involved to move sweaters, underwear, blankets, and other articles made of rather elastic materials relative to the stitching "mechanism. Also, in some factories, and in fact on some individual pieces of work, it is desirable to change very quickly from a fine to a coarse feed or vice versa. It'is an object of the present invention to provide a feeding mechanism which meets these problems efficiently.

Controlling mechanisms for feeding means are very often in awkward, inaccessible, or work impeding places. It is an object of the present invention to provide a control which will be easily accessible at all times, yet not impede the work, and which can be adjusted easily and quickly either by hand, knee, or by foot.

Features in connection with this aspect of the invention include a control mechanism on the frame which permits the top plate to be raised without disconnecting any parts; shifting from plain to gathered, shirred, or pleated effects easily'and quickly and on the same article and without stopping the machine.

In some machines it is. necessary to use different feed dogs and change the same in the machine in order to obtain correct spacing between the primary and secondary feed dogs for shirring and pleating effects.

It is an object of the present invention to provide mechanism which will eliminate the need of separate, different feed dogs and the trouble of changing the same.

To this end the present invention provides an adjusting mechanism adapted to effect relative spacing between the primary and secondary feed dog.

Other objects, features, and advantages will be apparent or will appear hereinafter.

In the drawings which merely illustrate the present preferred form of the invention:

Figurel is a front view of the overedge sew ing machine embodied in the present invention.

Fig.2 is a top view of the sewing machine shown in Fig. l.

Fig. 3 is a side view of the sewing machine.

Fig. 4 is a sectional view of the. differential feeding mechanism and the lubricating mechanism, mainly on line l4 in Figs. 1, 2, 7, and 10.

Fig. 5 is a sectional view illustrating the needle and trimmer operating mechanism and the lubricating system, mainly, taken on line 5-5 in Figs. 1, 2, 7, and 9.

Fig. 6 is a fragmentary detail view of the needle and trimmer operating mechanism in the down or operative position.

Fig. 7 is a top view similar to Fig. 2 but with the work table removed.

Fig. 8 is a fragmentary detail of the differential feeding mechanism.

Fig. 9 is a sectional view through the center of the main drive shaft, looking toward the rear of the sewing machine.

Fig. 10 is a sectional view taken on line 18-48 in Fig. 2.

Fig. 11 is a fragmentary detail, partly in section, of the looper driving mechanism taken on line l l'll in Figs. 2 and 10.

Fig. 12 is a fragmentary detail of the diiferential feeding mechanism.

Fig. 12A discloses a modified form of feed dog and feed dog carrier.

Fig. 12Bdiscl0ses .a modified form of presser foot mechanism. I

Fig. 13 is a'fragmentary and sectional view of one part of the feeding mechanism, taken on line l3-l3inFig.4.

Fig. 14 is a fragmentary view of a modified form of feed dog driving mechanism.

Fig. 15 is a fragmentary sectional view of the needle and trimmer operating mechanism.

The detailed description which follows is under various headings to facilitate an understanding of the various mechanisms and their mode of operation. The present invention is not limited to the details of construction and arrangement of parts illustrated and described herein, for the invention is capable of other embodiments in whole or part, in sewingmachines other than those of overedge type, and the phraseology used is for the purpose of description and not of limitation.

Main frame-and general structure The sewing machine embodying the present invention comprises a main frame 58 having a bottom 5|, and having front, rear, left side, and right side walls 52, 53, 54, and 55 respectively, preferably forming a reservoir 56 for lubricant 51. A plug 51' may be provided to occasionally draw off thelubricant. A glass insert 58 may be provided to indicate the level of lubricant in the reservoir. Rubber or other resilient plugs 49 in bosses 49' are provided to 'minimize vibra-- tion between the machine and bench.

A work'plate is supported on the main frame 58 by preferablyspaced pivot connections 6!, including suitable rearwardly projecting lugs 62 onthe main frame 58 and cooperating lugs 83 on the work plate 88 with shoulder screws 64 therebetween, as may be seen best in Figs; 2 and 3.

Ashoulder on the work plate is adapted to enoperating instrumentalities. Preferably, the work plate is provided with a depending apron 68 to prevent oil spray from leaking out through the joint between the work plate 80 and the rear wall 53, and particularly to throw the spray between the moving parts within the machine itself.

The work plate 60 may be locked relative to the main frame 58. In its present preferred form (Figs. 1 and 7) this is accomplished by providing a pin I4 in the work table adapted to enter a cooperating aperture in the main frame 58 whereupon a beveled end 14' thereof pushes a catch 15, best seen in Figs. 1 and 7, in a clockwise direction about a pivot 15' against the pressure of a spring 18 until the work plate is fully in the down position, whereupon the catch 15 is urged into a suitable groove in the pin 14 by the spring 16. The widely spaced hinges 6i,'and the pin connection and catch just described, rigidly support the plate and frame relative to each other and prevent adverse rattling or vibration.

In order to provide an effective oil seal between the main frame 50 and the work plate 88 and also to provide a very effective noise and vibration absorber, the present invention provides a cork, felt or like pad 10, preferably located in a suitable channel H in the top edge of the various sides 52 through 55. Theunderside of the work plate rests upon this pad, which in the concave section 12 (Figs. 7 and 10) of the frame supports the bearing cap 13 and prevents oil leakage past it.

The work plate 68, preferably, and as shown, is adapted to advantageously support a trimming mechanism 11, thread control mechanism 18, a presser device 19, and a trimming mechanism and presser device shifter 80 on its upper side, and to support a main drive shaft 8| and associated needle operating, looper, differential feeding and main driving mechanisms, 82, 83, 84, and 85 respectively on its underside. All of these' mechanisms will now be described in detail.

Main driving mechanism The main driving mechanism 85, best seen in Figs. 2, 4, 5, 6, 7, 9, and 10, preferably comprises a substantially one-piece main drive shaft 8| having a split sleeve bearing 86 near the middle and having a ball bearing 81 at the right side and a similar ball bearing 88 on the left side. The bearings 86 and 88 are supported and clamped in suitable bores 86' and '88 between the work plate 68 and cap sections 89 and 880i a suspended housing or bracket '9! as by screws 82, and the remaining bearing 81 is similarly supported and clamped in a coaxialbore 93 between a cap 13 and the work plate 80 by screws 94'.

Axial movement of the main drive shaft 8!, (seen best in Fig. 7), may be prevented by one or more of the following: The ends of the split bearing 86 engaging flanges on the main drive shaft; the flange 85 and pulley hub 96 engaging bearing 88.

A main drive pulley 99 is secured to the right end of thedrive shaft in any suitable manner: for example, and as shown best in Fig. '7, by ,a set screw I sliding in a spline slot IOI to prevent relative rotation, and a screw I02 adapted to prevent relative axial movement.

Although it would be possible to have the coaxial section I03, head 90, and eccentric I04 integral with the remainder of the main drive shaft 6|, they are preferably made separate and secured into a bore I05 in the left hand end of the main drive shaft by a screw I06 entering a suitable spline or hole for relative arcuate locating and a screw IN to prevent relative axial' movement as may be seen best in Figs. 7 and 12. The section I03 is a shank integral with the head 98; the adjustable eccentric I04 andadjusting mechanism therefor is substantially like that disclosed in the J. P. Weis Patent No. 1,118,321 and the A. H. Weis Patent No. 1,574,270.

Main feed adjustment Occasionally it may be desirable to effect major changes in the feed. For example, it may be desirable to change the machine from 10 stitches per inch as provided by the control, to stitches per inch. According to the present invention this is accomplished by a slide connection, between the eccentric I04 and the head 90, comprising a T-shaped tongue and slot connection I09.

A screw I I0 associated with the tongue and slot connection I09 and held against axial movement in the large head 96- is provided to regulate the position of the eccentric I04 while a nut III and washer H2 at the outer end thereof are adapted to rigidly clamp the eccentric against a face on the head 98 to maintain it in the-adjusted position. By tightening the nut III lightly'a snug slidable fit is provided for the eccentric, in which a screw driver may be passed through a hole H3 in the work plate 60 to adjust the eccentric with- .out lifting the work plate or disassembling the machine. The eccentric 404 is a sleeve adapted to be located various distances from the axis of the main drive shaft and to be snugly or rigidly maintained in the adjusted position.

. Thus, the present invention provides an adjustable main driving eccentric I04 on the main drive shaft 0| adapted to impart various extents of motion to the feeding mechanism 84, as is more fully described hereinafter.

Oil retainers II4 may be provided in the ball bearings 81 and 60 to prevent oil from escaping. The bearing cap I3 is provided with a collar II5 extending from within the frame to a position overlying the side wall 55 of the main frame, as

may be seen best in Fig. 7; adapted to engage with and rest upon the cork or similar pad I0 underlying it in a channel coextensive with the channel II. In addition to the adjustable eccentric I04 just described in detail, the main drive shaft is provided with a feed lift crank H6 and an upper loopercrank II'I on the left side of the bearing 86 and with a combination needle and trimmer operating crank H6 and a lower looper,

crank II9 on the'right side as may be seen best in Figs. 5,6, '7, 9, and 10.

Needle operating and trimming mechanisms A needle operating and trimming mechanism 82 and I1, respectively, of the present invention are of very novel construction and are much more completely described and claimedin my copendingapplication Serial No; 11,488 filed March needle carrier I2 I.

16, 1935. Sufllce in the present description to state that the needle operating mechanism comprises a needle carrier I2I having a preferably integral shaft I23 pivotally supported for arcuate movement in bearings I24 and I25 on the underside of a top housing I26 secured to the work plate 60 by screws I21, as may be seen best in Figs. 1, 2, 3, 5, 6, and 9. The needle I may be clamped in a suitable hole of the carrier arm I22w by a nut I26. The top housing is provided with depending lugs forming the bearings I24 and I to pivotally support the shaft I23 of the A rearwardly extending arm I29 is secured to the shaft I23 by a yoke I30 and screw I3I to hold an eccentric I32 against the left side of the housing I26 and thereby prevent axial movement.

A duct I33, closed at the end by a plug I34, extendingthrough the shaft I23 through a hole I35, joins with the oil groove 68 in the housing I26 and work plate 60 in order to effectively oil the bearings I24 and I25 and the eccentric I32 through suitable oil escape apertures I36 and I31, and I36 respectively. If any oil drips out of these bearings it will merely drop onto other operating mechanism or into the reservoir 56,

shaft integral with the needle carrier I2I there is no danger of relative shifting. Since the shaft I23 is, according to the present invention, disposed very close to the path of travel of the materials being sewed and close to the point of stitch formation, the carrier arm I22 may, as shown, be made very small, short, and very light.

In order to impart oscillatory movement to the needle I20 and carrier arm I22 from the raised inoperative position shown in Fig. 5 to the lowered operative position shown in Fig. 6, the present invention provides a very short crank connection comprising a crank-arm I40 secured to the crank II8 as by a conventional cap MI and screws I42 and joined by a pivot stud I43 to the rearwardly extending arm I29 as may be seen in Figs. 5, 6, and 9 particularly, thus providing very short and substantially direct driving connections with very little inertia.

The trimmer mechanism 11 comprises an upper I69 in the cutter carrier I46 so that the trimming mechanism may be shifted laterally relative to the needle.

The upper movable cutter I44 cooperates with the lower substantially stationary cutter I5I secured to a slide I52 by a screw I53 and normally pulled to the right as viewed in Fig. 1 by a spring I62 so that the two cutters I44 and I5I are always in cooperating engagement. A downwardly projecting finger I64 on the upper movable cutter prevents the ,lower cutter from moving directly under the upper cutter and thereby insures a close shearing engagement and close working relation between these two. The slide 152 which carries the lower cutter is suitably supported on the frame.

Presser device I g The presser device 19 which may be seen best in Figs. 1, 2, and 3 comprises a carrier I secured on a rod I8I by a screw I82, the rod having axial and rotary movement in the upstanding lugs I48 and I49 on the upper side of the work plate 68. As may be seen best in Figs. 1 and 3, the carrier block is provided with a finger I83 having a channel I84 adapted to receive a spring carrier-arm I85 and to locate it against lateral displacement while a screw I86 holds it against vertical displacement relative to the block. Divers presser feet I81 may be secured to the front end of the spring carrier-arm as by a pin connection I88. The long spring I85 enables the presser foot I81 to exert substantial pressure on the materials in their relation with the feed dogs I89 and/or I98 of the feeding mechanism 84, yet enables the presser foot to yield for cross seams, supplementary thicknesses, etc. in the work as it is fed rearwardly through the machine.

The main pressure of the presser foot toward the work plate is accomplished by a coil spring I9I located in a suitable bore I92 in the carrier block I88 as may be seen best in Figs. 2 and 3, preferably having a ball I93 at the lower end adapted to slide over the work plate 68. The bore I92 prevents the spring from tilting and cramping the carrier block, while a screw stud I94 permits various pressure adjustments.

Secondary pressure control is provided by a regulating screw I95 on a finger portion I96 of the carrier block. This screw may be made long enough'to engage the spring carrier-arm I85 and may, as shown, be provided with a lock nut I91 to maintain the screw in adjusted position. This regulating structure also serves the advantageous purpose of preventing adverse strains on the screw I86, since a considerable lifting leverage might be applied thereto because of the substantial length between the screw I86 and the presser foot I81.

In the modified form of presser device 19' shown in Fig. 123 the carrier-arm I85 is in the form of a fiat spring clamped in the channel I84 with the screw I88, and having an interponent I98 secured thereto by a screw I99 holding a presser foot I81. Particularly it provides an auxiliary spring 288 in order to obtain the desirable action of a leaf spring effect between the carrier block I88 and the presser foot I81. This secondary spring is preferably connected to the carrier-arm I85 in the channel I84 with thescrew I88, and is provided with a bowed section 28I under the adjusting screw I95 and has an end 282 engaging substantially the middle of the carrier-arm I85, making it possible to use a much lighter weight material in the spring carrier-arm I 85 and thereby obtaining better yielding action in the presser device.

An arm 283 extending rearwardly of the carrier block I88 is provided to lift the presser foot into an inoperative position relative to the work plate 68. Preferably, it is provided with any usual type of foot 'treadle connection.

The presser foot mechanism is more completely disclosed and described in my copending application, Serial No. 86,922, filed June 24, 1936.

Trimmen and presser device shifting mechanism The trimmer and presser device shifting mechanism 88 is disclosed best in Fig. 2 and compresser device 13. By rotating the screw member 281 in one direction, the trimmer and presser main drive shaft.

devices are shifted transversely in one direction relative to the line of feed and when rotated in the other direction are shifted transversely in the opposite direction transversely relative to the line of feed. The shafts I41 and I8I move both to the right and to the left in lugs I49 above the top plate 68, as is apparent by viewing Fig. 2.

.The shifting mechanism is much more completely disclosed and described in application Serial No. 11,488 filed March 16, 1935.

Looper mechanism The looper mechanism 83 may be seen best in Figs. 9, 10, and 11 and comprises a lower looper mechanism 286 and an overedge looper mechanism 281, the latter having a retracted position under the work table 68 (Fig. 10) and an advanced operating position above the work table and materials being sewed. The looper mechanisms are capable of forming the usual single, double, and triple thread overedge seams, and are much more completely described in the copending application Serial No. 11,488, filed March 16, 1935.

Sufiice, herein to state that the lower looper mechanism 286 comprises a looper carrier arm 288, supporting a looper 289, on a shaft 298 pivotally mounted in a bearing 29I on the depending housing or bracket 9|, and having an arm 292 extending laterally of the machine to a crank connection 293 with the crank II9 on the main drive shaft. Preferably, the connection comprises a crank-arm 294 with a ball and socket joint 295 at the upper end and a similar ball and socket joint 296 at its lower end. The lower looper 289 is secured to the looper carrier 288 by screws 291 and may be readily interchanged for the other slightly differently shaped loopers when the size of the thread," materials being operated upon, stitch, or other similar factors make such change desirable.

The overedge looper mechanism 281 comprises a looper carrier 298, interchangeably supporting a looper 299, on" a shaft 388 shown in Figs. 10 and 11 and which has a secondary arm 38I with a crank connection 382 to the crank II1 on the The crank connection preferably includes a crank-arm 383 havinga ball and socket joint 384 at its upper end on the crank I I1, and a similar ball and socket joint 385 to the arm 38I at its lower end? The shaft 388 is journaled in a bearing 386 of the depending housing or bracket 9I. The carrier 298 supports a looper 299 on a pivot 381 which has a secondary pivotal connection 388 intermediate its length on a of the looper 299 are moved down and wherein the crank-arm 389 is similarly moved down so that the top end of the looper is underneath the work support and is in a retracted position relative to the materials being sewed.

However, when the crank I I1 is rotated toward the lower position as viewed in Fig. 10, it imparts a clockwise rotation to the, shaft 388 initially lifting the looper 299 to a point above the top of the work plate 68 and then imparting a counterclockwise movement to the looper in order to move the thread carrying point thereof over the top of the material for well known cooperation with the needle I20.

In general, and dependent upon the type seam desired, the lower looper mechanism 286 may carry a hook-type looper, or may be an eye-type loop er 289 as shown in Fig. 10. Similarly, the overedge looper mechanism 281 may carry a hook-type overedge looper or an eye-type over edge looper 299 as shown in Fig. 10.

The novel thread tensioning and control mechanism 18 best seen in Figs. 1 and 2, is completely described and claimed in a copending application, Serial No. 118,061, filed December 29, 1936.

Feeding mechanism The object of a differential feed in a sewing machine is to overcome stretching of elastic materials such as knit materials from which sweaters, bathing suits, underwear, and other clothing are made, and also when operating on soft material such as blankets, serges, felts, laces, open mesh, and other articles employing delicate materials that may be condensed or compressed into smaller space than they normally occupy.

'This differential feed is arranged so as to have a movement approximately three and onehalf times greater than the main feed and its motion may be varied during the operation of the machine by the control lever, either by hand, foot treadle, or knee shift. Regardless of the .speed'at which the machine is operating, this shift will change the motion of the feed on the work so as to cause it to'gather if the movement of the differential feed is greater than that of the main feed.

Suitable feed teeth or surfaces and difierences of feed will enable not only gathering, but shirring of the material or ruilling or pleating, within the limits and scope of the. arrangement and de.-, sign of the parts. That is to say, if the differential feed has but one tooth to contact with the work,it will permit the work or material to fold upon itself, forming distinct ruflles or pleats because the material will fold upon itself, especially if it be woven materials. If sufficient action be given to the differential feed, a distinct pleat can be effected.

On the other hand, if the differential feed contacts with a larger portion of the material, as for instance, several teeth are brought to bear upon the same, the effect is a shirring or gathering action, rather than a" pleat or fold. The goods is pushed together, so to speak, and that is the desired function in most cases, especially on feed, and a great variety of effects can be pro duced by special designs of presser feet. The

length of the foot, the shape of the pattern end, the width of its bearing surface on the goods, and the amount of pressure, all must be considered 'and arranged to bring about the desired function and effect of the differential feed.

The differential feeding mechanism 84, best seen in Figs. 3, 4, 7, 8, 10, 12, and 13, comprises a feed dog carrier 235 having a. pivotal connec-' tion 236 with a shaft231 on afeed rocker frame 238. A primary feed dog I89 is secured to the front end of the main carrier 235. (Figs. 4, 7, and 8) with a screw 242, and a differential feed dog I90 may also be slidably secured thereto by a screw 243. Both feed dogs reciprocate in a slot 244 in a needle plate 245. Substantially midway of its lengththe carrier 235 is provided with a interchangeable sections feed-lift connection 246 (Fig. 9) including a split bearing 241 fitting upon the crank H6 of the main drive shaft BI which in turn slides in an elongated slot 248 (Figs. 8 and 9).

A feed rocking connection 249 (Figs. 4, '7, 8 and 12) is provided to impart variable extents of movement to materials on the work plate 60 under the presser device 19 and relative to the needle I20 and primary feed dog I89. Main feed and greater feed rocking movement is imparted to the frame 238 and carrier 235. r

In order to effect the major adjustments of the eccentric I04 on the head 98 for various extents of feed, the present invention provides a hole H3 and a slide 3' in the work platev 60 so that it is possible to move the adjusting screw IIO with a screw driver alone, when the nut III is tightened only enough to insure a snug sliding fit rather than a locked fit between the eccentric I04 and head 98. When it is desired to have a. lock fit, a wrench may be passed down through an opening 30:. Thus, it is not necessary to lift the work plate whenever major adjustments are made to the eccentric.

The mechanism for moving the differential feed dog I90 (Figs. 4, 7, and 10) comprises the mechanism just described and a forwardly extending crank 254 connected to the eccentric I04 at one end, and at its other end having a pivot connection 255 with a block 256 slidably mounted on a link 251. The link is, by a stud 260, link 258', and screw 260" at its upper end connected to a differential feed dog carrier 2 58, which is slidable'in a slot 259 in the main carr er 235. The carrier may be made of two pieces with held together by screws 2351) if preferred. At its lower end the link 251 is pivoted on a stud 26I. Divers differential feed dogs I90 may be connected to the differential feed dog carrier 258.

Viewing Fig. 4, it will connection 254 extending and the slide block 256 can be shifted up and down on the curved arm 251. When the block is shifted to the highest position on the curved arm, the angular relation of the crank connection254 is' changed a number of degrees from the position shown. This effects a slight change in timed relation. Instead of the two feeds working in unison or as one feed, when the parts are shifted to the highest position, there is a slight retarded movement to the feed dog I90. The movement is slowerthan' the movement of feed dog I89 because the crank is operating in a'direction towards the top or working surface of the machine.

This lifting motion of the bearing end of the be seen that the crank from the eccentric I04,

crank connection 254 causes this retarded moverelation and movement to the differential feed dog I90 in relation to the main feed dog I09. This is important to bring about the wide range of effects desired in stitching diiferent kinds of materials. All of these effects are instantaneously produced during the operation of the machine by shifting the lever 21I.

Since it is important to accurately position the differential feed dog I with respect to the main feed dog I89, an eccentric bushing is provided thatfits over the screw 26I. This bushingv operates in the bearing and is clamped in fixed relation by nut 26I' tapped into the curved arm 251. This eccentric bushing is indicated by 262 in Fig. 4.

By loosening the nut 26I' and turning this bushing, the arced relation of the arm 251 is changed so that as the slide block 256 is shifted up and down, the feed dog I90 may be brought to a position very close to the main feed dog I89, while in another position, the adjustment of this eccentric bushing will cause a considerable space to be maintained between the back left hand edge of the differential feed dog I90 and the front right hand edge of the feed dog I89, leaving a space between the two, and this space is'useful for goods to ,expand or enter therebetween as it is carried past the stitching position. Then too, this adjustment is very important when the machine is arranged for making 20 stitches to the inch under certain requirements, or on the other hand, making a long stitch, 5 or 6 to the inch depending upon the requirements. Were it not for this eccentric bushing, the differential feed dog I98 would require shifting or an endwise adiustment to meet the requirements, or replacement of feed dogs;

Shifting of the slide block 256 into various stations in order to effect a differential feed is preferably accomplished instantaneously, without direct manual adjustment of slide block 256, and without the necessity of lifting the work plate 68 from the main frame 50 by the provision of a control arm 263, which as shown may be advantageously formed as a bell crank, pivotally mounted on a stud 264,'having a novel spring strip connection 265 under screws 266 and 261 to the slide block and having a pin 268 at the end of the shorter arm 263' of the bell crank. An arm 269 is secured to a stud 210 which is pivotally mounted on the left side wall 54 and is substantially coaxial with the stud 264 when the work plate is in a lowered position and resting on the pad 10. As clearly shown in Figs. 4 and 10, the arm 269 has a guiding rim 211 projecting from its sides toward the inside of the frame, and a slot 280 at the lower end of the rim 211 of a width to accommodate and receive the pin 268.

A lever 21I is secured to the stud 210 at the outside of wall 54 and may be provided with any suitable foot treadle or knee shifting mechanism, and is also conveniently located for hand shifting, connected to the front and rear ends 212 and 213, respectively. Regulating screws 214 and 215 in a lug 216 limit the extent of clockwise or counter-clockwise movement of the outer lever and associated slide block 256. A spring 218 may be provided to normally urge the lever and slide block 256 into the maximum feed position when positioned as shown by solid lines, or into minimum feed position when in dot and dash position shown in Fig. 3, dependent on whether the work is mostly plain or mostly gathered,-pleated, or the like. The slide block 256 may be provided with a slightly bowed flat spring 219 (Fig. 14) adapted to press against the link 251 and frictionally maintain the slide in any position on the link that it is moved to. As clearly shown in Fig. 4, the rim 211 of the arm 269 only projects from the of the pin 268 on arm 263.

sides thereof leaving an interruption or opening 28I at the upper end of arm 269 for the insertion This special pin and slot connection 268, 288 enables the operator to raise the work plate without the use of special tools and without disturbing the adjustment of the regulating screws 214 and 215. Upon lowering the work plate, the pin 2 68 enters the opening 28I in the rim 211 and is guided by the rim into the slot 288.

Fig. 12A discloses a modified form of feeding mechanism 84a including a main carrier 235a to which only divers primary feed dogs I89a may be secured by screws 282. The crank 250 and frame 238 actuated by the adjustable eccentric I04 form a feed rocking drive. This is a much more economical feed mechanism to manufacture, for those machines wherein the secondary feed dog I90 and iiscontrols are not needed, as in sewing materials which do not stretch unduly. Jack-screws 282' are provided to tilt the feed dog relative to the presser foot.

The feed dog I89 is shown as a separate element secured to a separate carrier 235 by screws 242, and is preferably so made in order to facilitate changing from one type of feed dog to another. However, the feed dog I89 and can'ier 235 may be made in one piece and thereby dispense with screws for economy in manufacturing cost and rigidity in use, if preferred.

If preferred, a single link 251' and shorter crank 254', as shown in Fig. 14, may be provided in place of the double link 251 and 258 hereinbefore described in which event a slot 251a engaging the stud 260' is used to permit the upper end of the link to travel relative to the stud and to drive the dog I90 relative to the carrier 235. However, the double link construction is preferred for a smoother action and less wear.

By having the feeding mechanism compact and fully enclosed within the casing comprising the main case 58 and the top plate 68, it is possible to thoroughly lubricate the feed mechanism parts without danger of oil spray reaching the work. Also, it is possible to effect a gravity feed of oil to various moving parts of the feed mechanism, as will be apparent by viewing Figs. 2 'and 9 wherein there is disclosed web 61' extending from the channel 61 down which oil runs and drips onto the bearing parts between the carrier 235 and eccentric II6, see Fig. 9. Similar webs 354, 355, and 356 may be extended from the main channel 61 in order to oil other parts of the feeding mechanism. The complete lubricating means are disclosed and claimed in the copending application Serial No. 50,460 filed November 18, 1935 which also describes and claims the drip webs 380, "I, 382, and 383 of the cover 360 and thecontact between channels 66 and 66' of the top plate 68 and frame 58.

Operation the feeding mechanism 84 is operated 'by the crank shaft 8| coordinately with the stitch forming mechanism. The plain form of feeding mechanism 80a shown in Fig. 12A, with only one feed dog may be used for the ordinary run of work, and various extents of horizontal movement to obtain 10, 12, and other quantities of stitches per inch may be imparted to the feed dog I89a upon each rotation of the crank shaft 8| by merely setting the adjustable eccentric I04 with the tongue and slot connection I09.

Differential feeding by the mechanism 84 is accomplished in a somewhat similar manner. The primary feed dog I89 thereof is driven and adjusted in the same manner as the feed dog I89a. just described. The secondary feed dog I90 is operated synchronously with the primary feed dog I89 by the crank 254 extending from the eccentric I04 to the slide block 256 oscillating the link 251 about its pivot, and through the link 258 reciprocating the secondary feed dog I90 in the feed dog carrier 235. By shifting the slide block 256 upwardly on the link 251, shorter travel is imparted to the secondary feed dog, even to the point of obtaining less travel for the sec- 7 ondary feed dog than the primary feed dog, and

by moving the block down on the link, as through the pin and slot connection 268, 280, the sec-, ondary feed dogcan be made to travel just the same extent as the primary feed dog to form a supplemental feed, or can. be made to travel a much greater extent in order to gather, shir, or.

pleat materials.

In order to pleat materials it is preferable to have a considerable space longitudinally between the two feed dogs, and in order to effect this spacing without changing the feed dogs, the present invention provides the eccentric bushing 262.

When the eccentric is turned in a clockwise direction as viewed in Fig. 2, the space between the two feed dogs is increased, and when it is .moved in a clockwise direction, the feed dogs are brought closer together which is a preferred condition when plain feeding is desired.

Because of the particular pin and slot connection 268, 280 between the control arm 263, 263' and the arm 269 on the stud 210, a considerable advantage is obtained, for the top plate 60 can be moved relative to the main frame 50 without disturbing the setting 'of any of the feeding mechanism parts. The lever 2' with the screws 214 and 215 makes it possible to effect quick movement of the secondary feed dog I90 into predetermined ratio of feed relative to the primary feed dog I89, and the spring 218 serves 7 v to normally maintain the secondary feed dog in the minimum or maximum feed position as preferred. V y

In some classes of work it may be-desirable to have just one feed 'dog, which however may be quickly changed from a slow feed, to form 20 stitches per inch for example, to a high speed to form only 8 or 10 stitches per inch, in which event the present invention makes it possible to remove the feed. dog I89 and use only the feed dog I90 with the associated controlling mechanism 268.

Other variations and modifications may be made within the scope of the present invention, and portions of the improvements may be used without others.

Having thus described the invention, what is claimed as new is:

1. In a sewing machine the combination of a frame; stitch'forming mechanism; a drive shaft;-

1 a presser'foot; a feed dog; a feed dog carrier; a

said feed dog; a sliding connection between the feed dog and the carrier; a pair of links associated with the feed dog; a second eccentric on the drive shaft; a crank extending from said second eccentric to one of said links to effect minimum and maximum extents of feed; and resilient friction means to maintain said crank in predetermined positions on the link.

2. In a sewing machine the combination with a frame; of a top plate pivotally movable to raised and lowered positions relative to the frame; a drive shaft; a stitch forming mechanism operatively connected to the drive shaft; a presser foot; a feed dog; .a feed dogcarrier; means for operating the feed dog synchronously with the stitchforming mechanism; and control mechanism for adjusting the extent of feeding movement of the feed dog including relatively movnously with the stitch forming mechanism; control mechanism for adjusting the extent of feeding movement of the feed dog including relatively movable control members on the top plate and on the frame; and means to maintain said control members in predetermined positions.

4. In a sewing machine the combination of a frame; a top plate; a suspended bracket on the top plate; a stitch forming mechanism; a presser device; driving means; a-feed dog carrier; 'a primary feed dog secured to said carrier; a secondary feed dog; a link connection between said bracket and carrier; a link connection between said bracket and the secondary feed dog; an ad justable eccentric; and at least one crank extending from said eccentric to at least one of said link connections.

5. In a sewing machine the combination of a frame; -a top plate; a suspended bracket on the top plate; a stitch forming mechanism; a presser device; driving means; a feed dog carrier; a primary feed dog secured to said carrier; a secondary feed dog; a link connection between said bracket and carrier; a second link connection between said bracket and the secondary feed dog;

an adjustable eccentric; a crank extending from said'eccentric to the second link connection; and a shiftable connection between said crank and' the second link connection.

6. In a sewing machine the combination of a frame; a top plate; a suspended bracket on the top plate; a stitch forming mechanism; a presser device; driving means; a feed dog carrier; a primary feed dog secured to said carrier; a secondary feed dog; a link connection between said bracket and carrier; a second link connection between said bracket and the secondary feed dog; an adjustable eccentric; a crank extending from said eccentric to the second link connectionfa shiftable connection between said crank and the second link connection; and means for operatively locating said secondary feed dog both closely and remotely relative to said primary feed dog.

7. In a sewing machine the combination of a frame; a top plate; a suspended bracket on the top plate; a stitch forming mechanism; a presser device; driving means; a feed dog carrier; a primary feed dog secured to said carrier; a secondary feed dog; a link connection between said bracket and carrier; a second link connection between said bracket and the secondary feed dog; an adjustable eccentric; a crank extending from said eccentric to the second link connection; a shiftable connection between said crank and the second link connection; and means exteriorly of the machine for .quickly moving said shiftable connection to predetermined positions.

8. In a feeding mechanism for sewing machines; a primary feed dog; a secondary feed dog; an eccentric to lift said feed dogs; means for imparting horizontal movement to said feed dogs; and means for locating the uniform backand-forth travel of said secondary feed dog in divers positions, both closely and remotely, relative to the primary feed dog.

9. In a sewing machine the combination of a frame; a main drive shaft on said frame; a primary feed dog; a feed dog carrier; a secondary feed dog slidably supported on the carrier; one eccentric on the main drive shaft adapted to lift said feed dogs; mechanism for imparting horizontal movement to said primary feed dog; a double link connection between said frame and said secondary feed dog; a slide block on one of said links; a crank extending from said main drive shaft to said slide block; and means for shifting said slide block on said link.

10. In a sewing machine the combination of a frame; a main drive shaft on said frame; a primary feed dog; a feed dog carrier; a secondary feed dog slidably supported on the feed dog carrier; one eccentric on the main drive shaft adapted to lift said feed dogs; mechanism for imparting horizontal movement to said primary feed dog; a double link connection between said frame and said secondary feed dog; a slide block on one of said links; a crank extending from said main drive shaft to said slide block; means for shifting said slide block on said link; and an cecentric forming the main pivotal mounting for the link which carries the slide block adapted to locate the secondary feed ,dog relative to the primary feed dog.

11. In a sewing machine the combination of a frame; a top plate; a suspended bracket on the top plate; a main drive shaft; only one feed dog carrier; a primary feed dog; a secondary feed dog slidably mounted on the carrier; only one eccentric on the drive shaft adapted to lift both the primary and secondary feed dogs; mechanism for imparting horizontal movement to said primary feed dog and' carrier; a link connection between said suspended bracket and the secondary feed dog;'a crank for operating the secondary feed dog; a slide block connection between the crank and the link; and means for quickly shifting said block on said link to effect different extents of horizontal travel of said secondary feed dog relative to the primary feed dog.

12. Ina sewing machine the combination of a frame; a' top plate; a suspended bracket on the top plate; a main drive shaft; only one feed dog carrier; a primary feed dog; a secondary feed dog slidably mounted on the carrier; only one eccentric on the drive shaft adapted to lift 7 both the primary and secondary feed dogs; mechblock on saidlink to effect different extents of horizontal travel of said secondary feed dog relative to the primary feed dog; and a flat spring connection between said last named means and the slide block.

13. In a sewing machine the combination of a frame; a top plate; a suspended bracket on the top plate; a main drive shaft; only one feed dog carrier; a primary feed dog; a secondary feed dog slidably mounted on the feed dog carrier; only one eccentric on the drive shaft adapted to lift both the primary and secondary feed dogs; mechanism for imparting horizontal movement to said primary feed dog and carrier; a link connection between said bracket and the secondary feed dog; a. crank foroperating the secondary feed dog; a slide block connection between the crank and the link; a bell crank pivotally mounted on said suspended bracket and having a connection with the slide block; and means mounted on'the frame adapted to cooperate with the bell crank to variously adjust the extent of travel imparted to the secondary feed dog while the extent of travel of the primary feed dog remains unchanged.

14. In a sewing machine the combination of a closed frame; a top plate; a suspended bracket on the top plate; a main drive shaft; only one feed dog carrier; a primary feed dog; a secondary feed dog slidably mounted on the feed dog carrier; only one eccentric on the drive shaft adapted to lift both the primary and secondary feed dogs; mechanism for imparting horizontal movement to said primary feed dog and carrier;

a link connection between said bracket and the secondary feed dog; a crank for operating the secondary feed dog; a slide block connection between the crank and the link; and means between said slide block and the exterior of the frame adapted to shift the slide block on the link to efl'ect various extents of secondary feed dog travel relative to the primary feed dog and to permit the top plate with the suspended bracket and associated'mechanism to be automatically disconnected and moved relative to the main frame.

15. In a sewing machine the combination of a frame; a stitching mechanism; a presser device; a feeding mechanism including a feed dog movable into minimum and maximum feed positions; controlling mechanism; a lever of the first class in said controlling mechanism; adjustable means at opposite ends of said lever to obtain and limit movement of said feed mechanism into various minimum and maximum feeding positions.

16. In a sewing machine the combination of a frame; a stitching mechanism; a presser device; a feeding mechanism including a feed dog movable into minimum and maximum feed positions; controlling mechanism; a lever of the first class in said controlling mechanism; adjustable means at opposite ends of said lever to obtain and limit movement of said feed mechanism into various minimum and maximum feeding positions; and means for selectively and yleldingly maintaining said lever in its minimum and its maximum feed position.

17. In a sewing machine the combination of a .frame; a drive shaft; 9. primary feed' dog; a

secondary feed dog; a carrier supporting both of said feed dogs; an integral eccentric on the drive shaft adapted to lift saidcarrier and said feed dogs; mechanism for imparting rocking movement to said feed'dogs; a head on the end of said drive shaft having a channel; and an adjustable eccentric movable and lockable in said channel adapted to impart various extents of movement to thefeed rocking mechanism.

18. In a sewing machine the combination of a frame; a main drive shaft; a primary feed dog; a secondary feed dog; a carrier for said feed dog; an integral eccentric on the drive shaft adapted to lift said carrier and feed dogs; a link for imparting rocking movement to the carrier and primary feed'dog; mechanism including a link: for imparting rocking movement to the secondary feed dog; a head on the main drive shaft having a channel; and only one eccentric having a slidable and rockable connection with the channel, and upon which both of said links are connected, to impart said rocking movement to both the primary and secondary feed dogs.

19. In a sewing machine, the combination of a frame; a top plate movably associated with said frame; feeding mechanism; and control means for said feeding mechanisms, including movable members carried by said frame and said top plate, separable upon movement of said top plate away from said frame. I

20.-In a sewing machine, the combination of a frame; ,a top plate movably associated with said frame; feeding mechanism carried by the top plate; and control means for said feeding mechanism including movable members carried by said frame and said top plate, operatively asso-' ciated with each other by a pin and slot connection to enable a separation thereof upon movement of said top plate away from said frame.

21. In a sewing machine, the combination of a frame; a stitch forming mechanism; a main drive shaft; a primary feed dog; a feed dog carrier; a secondary feed dog slidably supported on said carrier; a swing frame supporting one end of said carrier; an eccentric for lifting said feed dogs; a pivotally mounted link connected to said secondary feed dog; a slide block on said link; a crank connecting said main drive shaft and said slide block; and an eccentric forming the main pivotal mounting for said link adapted to locate said secondary feed dog in divers positions relative to the primary feed dog.

JOHN 1?. WEEKS.

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