US2386800A - Sewing machine - Google Patents

Description

Oct. 16, 1945. c. w. JOHNSON SEWING MACHINE Filed Sept. 7, 1940 8 Sheets-Sheet l am 9 M J m 7 x 0 INVENTOR BY CARL W. JOHNSON TTORNEY c. w. JOHNSON SEWING MACHINE Filed Sept. '7, 1940 8 Sheets-Sheet 2 CARL W. JOH SON -FIG.5

A ORNEY C. W. JOHNSON SEWING MACHINE Oct. 16, 1945.

8 Sheets-Sheet 4 Filed Sept. 7, 1940 INVENTOR I ATTORNEY Oct. 16, 1945. c, HN ON 2,386,800

SEWING MACHINE Filed Sept. 7, 1940 s Sheets-Sheet 5 FIG. I 311306123 2/5 INVENTOR BY CARL W.JOHN'SON ATTORNEQQY Oct. 16, 1945. C, w JOHNSON 2,386,800

SEWING MACHINE Filed Sept. '7, 1940 8 Sheets-Sheet 7 INVENTOR CARL W JOHN SON A ORNEY Oct. 16, 1945. c. w. JOHNSON 2,386,800

SEWING MACHINE Filed Sept. 7, 1940 8 Sheets-Sfieet s FIG.2O .7

- INVENTOR Oar-Z Z0, Jbhnson ATTORNEY Patented Oct. 16, 1945 SEWING MACHINE Carl W. Johnson, Brooklyn, N. Y., assignor to American Machine and Foundry Company, a corporation of New Jersey Application September 7, 1940, Serial No. 355,738

28 Claims.

This invention relates to a sewing machine and more particularly to sewing machines of the under and over stitch type in which the ends of a double pointed needle are alternately grasped by needle bars and projected back and forth through the Work as it is moved into the range of action of the needle.

The invention relates generally to improvements in a machine of the type shown in my pending application, Serial No. 289,907, filed August 12, 1939, for Sewing machine, and has as its chief object the provision of improved co-, acting elements which Will increase the general eificiency of the sewing machine and its scope of use.

It is an added object of my invention to provicle an improved sewing machine having a tension finger arranged to coact with the reciprocating needle on the thread adjacent the eye of the needle, and move it out of the path of the needle so that likelihood of the thread being engaged by the point of the needle is materially lessened.

It is a further object of my invention to provide an improved thread guiding device which acts as a medium for allowing the thread to be moved by the tension finger out of the path of the needle.

My invention also consists in the provision of improved driving mechanism which is localized in one general position to the rear of the machine so that there is more room available at the front of the machine for sewing instrumentalities and also the several driving gears employed are kept clear of lint and thread, thereby resulting in a more emcient and compact structure.

I have also provided thread guides for improving themovement of the thread so that it is always guided to proper position relative to the traveling thread puller and out of the path of the thread being pulled by said thread puller.

It is also an object of my invention to provide improved mechanism operating beneath the work support of the machine for tensioning the thread and moving it out of the path of the needle as it moves downthrough the support, and to provide also means for adjusting the amount of tension applied.

According to my invention the thread is under tension at all times and properly positioned relative to the needle. In order to prevent excess tension being imposed upon the thread as it forms the stitches and puckering the work, I have provided improved means for gripping the thread beneath the work support prior to the operation of the thread puller and means forming a part of the gripping device ,for'allowing the thread to be moved clear of the path of the needle.

A further object of my invention is to provide a pair of improved gripper arms which will aid in proper positioning of the thread in the cutout portion around the periphery of a drum.

An additional object of my invention is to provide a simplified and more direct means for operating the needle chucks in timed relationship.

Another object of my invention is to provide a simplified, faster operating and smoother drive for a thread puller arm.

My invention also consists in an improved arrangement of the thread receiving drum which will allow additional room for the operators legs and hence adds to the general efiiciency in the operation of the machine.

With these and other objectsnot specifically mentioned in view, the invention consists in certain combinations and constructions which will be hereinafter fully described, and then set forth in the claims hereunto appended.

In the accompanying drawings, which form a part of this specification, and wherein the several reference characters designate the same or like elements:

7 Fig. 1 is a side view, partly in section, of a portion of the improved sewing machine;

Fig. 2 is a front elevation, taken from line 22 of Fig. 1, the -handwheel and needle bar cam.

being omitted to more clearly illustrate the driving means; v

Fig. 3 is an enlarged detail view taken from line 3-3 of Fig. 1, showing the upper needle bar, the material feeding arm and its co-acting feed foot and presser foot;

Fig. 4 is a detail view illustrating the mounting of the looper' arm and tension finger as seen from line 44 of Fig. 3;

Fig; 5 is a detail view showing a portion of one its cam of the needle bars and the connection to actuated lever;

Fig. 6 is a detail view taken from line 6-6 of Fig. 5;

Fig. 7 is an enlarged sectional view of the improved needle bar in needle receiving position;

Fig. 8 is a view of a needle bar, partly in section, showing a needle grasped by the needle bar chuck;

Fig. 9 is a partial sectional view of a part of the needle bar showing the needle as it is about Fig. 12 is a plan view of a portion of Fig. 11

showing the improved thread tensioning mechanism;

Fig. 13 is a plan View of the improved threadguide used in conjunction with the thread tension mechanism;

Fig. 14 is a side view of thesame taken fromv line |4-|4 of Fig. 13;

Figs. 15, 16 and 17 are detail views showing the different stages in sewing the. work;

Fig. 18. is a plan view. taken from line |8-|8 of Fig.

Fig. 19 is a plan view taken from line |9,-|9 ofFig. 16;

Figure 20 is a. partial assembly view partly in section showing the relationship between the needle, needle actuating bars and other thread handling mechanisms; and

Figure 21 is a diagrammatic perspective view showing the coaction between the needle bars, looper, and tension fingers during the operation of the latter. 1

Referring to Fig, 1, the sewing machine, which is of the same general type as that shown in copending application, Serial No..289 ,90'7, filed August 12', 1939, by Carl W. Johnson for Sewin machines, consistsfof a center support frame and a combination end frame and housing 3|, the frames being secured to andjspacedl by supporting member 32 which in' turn are secured to the pedestal 33. of the machin'easshown in Fig. 2. The frame 39 .supportsa bracket 34 carrying the forward end of, the sewing machine table" 35; the rear end of the sam'ebeing secured to spaced blocks 36 which are. fastened 'to the frame 3|.

A pulley31'is driven by" a belt 38 which also runs over a pulley (not shown) integral with a clutch mechanism driven from a motor (not shown) in the same manner as disclosed in the copending armlication referredto' above. Therefore, thedrive as well as the mechanism for operating the clutch and a brake isomitted in the present case.

Pulley 31 is secured to the hub" of a gear 4| rotating about a stationary stud 42 fastened to the wall of frame 3| by screws 43. A handwheel secured to pulley. 31 is provided to permit manual turning of the machine. A- cam' 39 cooperates and rotates with pulley 31. This cam may be formed as a separate member; or as in the present application, it may be formed integral with and on the inside face of pulley 31. Cam 39 isprovided with a camtrack 45 engaging cam followers. 46. and 41. positioned. at diametrically opposite points of the cam, these followers being carried by the extending arm 48.and 49 at the rearward end of their respective oscillating 1e.- vers 50 .and 5|. ,The lev.ers 50. and 5| are pivotally, mounted on shafts. 52,.and. 53, respectively, shaft 52 being supported at; one end in a. hub 54 of a bracket 55 secured to the wall of member 3| and its other end being supported in a lug 56. extending from thebridge of member 3|. One end of shaft 53 ;is supp orted in a hub58 of a bracket 59 fastened to'the wall of member 3|; its other end is supported in a hub 60 of a bracket 6| attached to a support 62 fastened to member 3| as shown in Figs. 1, l3 and 14. An upper needle bar 63 and a lower needle bar 64 (Figs. 1, 3 and 14) arranged in axial alignment are provided with actuator members 65 connecting to extending arms and 61 at the forward end of their respective oscillating levers 50 and 5| whereby to convert the oscillating motion of said levers into a vertical reciprocating motion of the needle bars. The upper needle bar 63 is guided in bushings 68 and 69 carried by lugs 10 projecting from the forward end ll of bridge 51' (Figs. 1 and 3;); The lower needle bar 64 (Fig. 14') is guided in bushings l2 and 13 carried by lugs 14 extending from support 62,

The actuator members 65 heretofore mentioned are held in place on their respective needle bars 63 and 64 by lock nuts as seen in Figs. 5 and 6. The vertical extending. portion 16 oftrnembers 65 isprovided with a track "in which slides a rectangular block 18 inserted on the endofa studmfixed in the end of arms 66 and 61'. The sliding block 18 permits means for converting the oscillating motion of arms 66 and 61 into a, vertical reciprocating motion of the needlebars 63 and 64. The member 6513f the upper needlebar has an extension (Figs. 5 and 6) provided to perform an operation to be described presently.

Thismachine has a double pointed needle having a point at each end, and an eye about midway of; its length through which the thread passes. This needle is used in conjunction with the improved needle bars 63-. and 64. Since both needle bars are constructed in th'e same manner, like reference numerals will be used to designate like parts, and only one will be described.

Referring to Figs. '7 and- 8; the upper needle bar 63.-as shown' may consist of an outer shell which at its upper end has a threaded portion receiving a plug 86, having an aperture 8,! slightly larger than the diameter of the operating rod 88. Rod 88 at its lower end is provided withaplug portion 89; fitting into an aperture; 9B- of the inner shell 9|- which is held against a shoulder 92 of rod 88 by means of a pin93. The combined rod 88 and shell 9| are guidedin aperture 81 0f the plug 86 and in the aperture 9.4 of: shell 85. The shell 9|, at its lower end is provided with a. seat- 95 adapted to serveas a stop for the base of the cageor ball retainer portion 96 0faslidable plug 91 guided in the. aperture 960 f shell 9|, The plug 91 is normally held inthe position shown in Fig. 7, abut.- ting the; seat 95 by a eompressionspring 98.

The lowerportion of shell 85 is equipped with a stud 99, Fig, 9, the-same being held in place by a split wirering lllll fitting into an annular groove |0.| in shell 85; and in-the open end slots I0 2 provided. in st1l d 99, thereby providing a means for quick and easyremoval for cleaning and replacement. The stud99; is provided with an opening [03}formledto suit the point of the needle and serves to stop theneedles at the same position eachtime it is transferred from one needle bar to the other.

It willbe understood by those skilled in the I artlthat. in this type of machine the needle 8| is -alternately grasped by the jaws of each needle bar.- The action is such that as the lower needle bar 64 advances the needle inwardly through the work, it passes through the opening I04 in the lower endof shell 9-| of the' upper needle bar 63, and openings I in the cage 96 and stops against stud 99 in the opening I03 as seen in Figs. 7 and 9. The upper and lower needle bars 63 and 64 are identical in construction and operate in the same manner for gripping and releasing the needle in projecting the same back and forth through the work so that the operation of only one needle bar need be described in detail. During the transfer period, shell 9| comes to rest because of the engagement ofshock absorber III with a bushing 68. At the same time, shell 85 of the lower needle bar 64 connected to arm 6! continues its upward movement relative to the cage '96 of plug 91, then resting against stop portion 95 of shell 9| so that due to this relative movement, tapered portion I0! of shell 85 moves away from rollers I06 to release and grip on the lower end of the needle held thereby. The round needle 8| may be provided with grooves I08, Fig. 10, thereby providing better meansfor the balls I06 to properly obtain a firmer grip on the needle.

With the needle in position, the oscillating lever 50, previously mentioned, carries the shell 85 of the needle bar 63 upward, whereby the balls I06 become wedged between the needle 8| and the tapered wall I01 thus firmly gripping the needle, at the same time, the gripping balls of the lower needle bar are released and the continued ascent of shell 85 causes the needle 8| and ball retainer plug 9? also to rise, as seen in Fig. 8. When the eye 82 of the needle 8| is in a position close to the base of shell 9|, the stud 99 carried by shell 85 which has ascended freely in an elongated slot I09 in shell 9| held stationary with respect to shell 85 until shock absorber III is lifted from bushing I68, abuts the upper end of the slot I09, and the travel of shell 85 efiects the movement of the several parts of the needle bar unit (as shown in dotted lines in Figure 8) thereby carrying the needle through the work. By supporting approximately half the length of the needle, the possibilities of breaking or flexing of the same is greatly reduced during subsequent operations presently to be described.

A spring III) is confined in the aperture 94 of shell 85 and normally tends to hold a shock absorber III made of rubber or any other suitable material, which may be integral with a knurled nut M2 on rod 88, against the face of bushing 68. The tension of spring I I0 is great enough to overcome the tension of spring 98 which therefore causes the latter to be compressed (Fig. 8) during the needle gripping and positioning operation heretofore mentioned.

The upper needle bar 63 descends as a unit until the shock absorber I I I abuts the face of bushing 68 and arrests the travel of rod 88 and its coacting shell 9|. The shell 85 and plug 91 continue their downward travel and finally the base of the cage 96 abuts its seat 95 stopping the travel of plug 91 but the shell 85 continues downward slightly, as indicated by the dotted lines in Fig. '7, thus releasing the gripper balls I06 freeing the needle. It is understood that the needle has passed through the work and entered into the lower needle bar 64 and is being gripped by the latter in the manner that the upper needle bar accomplishes the same. The movement of rod 88 and shell 9| of the lower needle bar unit is controlled in the same manner as the upper needle bar, that is the rod 88 carries a shock absorber I I I which abuts the face of the lower bushing 13 as seen in Fig. 14.

The nut II2, on rods 88, provides means for adjusting the gripping elements |06I0| of each needle bar (Figs. 7 and 8). When properly adjusted, nuts I I 2 are held in place by lock nuts I I3. In transferring the needle from one needle bar to the other, both shells 85, for a short distance travel in unison, that is one moves to release the needle and stops, while the opposing one grips the needle and continues its travel to carry the needle through the work.

Referring to Fig. 9a, means are shown whereby the needle bars can easily and quickly be adapted to receive difierent size needles. The base of sleeve 9| may be provided with a tapped hole 5 to receive a threaded insert or bushing II6 having an opening II! which is slightly larger than the diameter of the needle to be used. If a needle of larger or smaller diameter is desired, member H6 can b readily removed and replaced by a like member having an opening to accommodate the new needle. The openings I05 in the cage 96 are large enough to accommodate the maximum size needle.

A presser foot I20 (Figs. 1 and 3), used in conjunction with a feeding foot |2| and a feed plate I22 attached to a cam actuated arm I23, is provided to engage and retain the work in position during the sewing operation. The presser foot I20 is clamped to the lower end of a rod I24 guided in the upper and lower lugs '10 of member II. The upper end of rod I24 supports a bar I25 which is clamped between lock nuts I26 and supports one end of the tension springs I21 which connect to the upturned ends I28 of a-plate I29 fastened to the upper lug I0. The springs I21 normally tend to hold foot I20 in work position and since the bar I25 can be moved up and down on the rod I24, the tension of the springs I2! can be adjusted so as to exert the desired pressure of the foot to suit different types of work.

A block I35 which is clamped on rod I24 supports one end of a link I3I connecting to a lever I32 loosely mounted on a stud I33 carried by an arm I 34 which in turn is fastened to the bar portion I35 of a rod I 36. The vertical extending arm of lever I32 supports an arm I31 connecting to a crank I38 of a rotating shaft I39 whereby an up and down motion is imparted to the presser foot I20 and the feeding foot |2I which is attached to the bar I35. The upper end of rod I36 is guided in a swivel block I46 and may be equipped with trunnions |4I mounted in open end slots I42 provided in the supporting member I43 which also carries fiat springs I44 adapted to engage and hold the trunnions MI in position. Bar portion I35 of rod I 36 is guided in a slot I45 provided in the lower lug E0 of member II, said lug also having tapped holes I46 to receive screws which hold a guide plate (not shown) in place. A plate I47 attached to the lugs I0, is provided with an elongated slot I48 which guides the movement of the arm I34. Shaft I39 (Figs. 1, 2 and 3) is rotated by a gear I50 in mesh with an intermediate gear I 5| driven by the main gear 4|. Gear |5| is mounted on a stud I52 supported by the end wall of housing 3|.

To facilitate the starting of new work, and also permit the operator to inspect the work at intervals during sewing operations, presser foot I20 and feed foot |2I are so arranged that they may be lifted whenever the operator desires. This feature is accomplished by providing a knee plate I53 (Fig. l) which is adjustably fastened to a rod I 54 by a thumb screw I 55, the upper end of rod I54 connecting to a head I56 clamped to a cross shaft I57. Shaft I5! at one end is pivotally mounted in a. bearing of: support. 32 audits. other end ,mounted-in a bearing of a. bracket I581 fastenedtothesupport 62'. Anarmi I59; isfixed toshaft I51, and coacts. with a. bar I60 slidable.

in. a vertical track I6I. provided in. housing 3|,

the upper end of the bar. I.60.engaging. a pin. I62

turn shaft I64? whereby the fingerv I65 engages.

collar I66 and lifts the presser foot I20 and through its connections. will also lift feed foot I'2I.

carried by member 62 tends to reset the unit.

A looper cam I10 (Figs. 1 and 2) engages a cam.

roller I1I which is mounted ona stud I12 carried by a lever I13 fastenedon a cross shaft I14. The cam roller I1I is held in engagement with cam I10 by means of a spring I15 which is stretched between a post I16 in lever I13 and a post I11 in a lug I18 extending from housing 3!. Shaft I14 at one end is supported by housing 3| and its other end in a hub I19 of a bracket I80.

(Fig. 3) secured to the face H of bridge 51.

A looper arm I8I (Figs. 3 and 4) secured to shaft I14 at its lower end is provided with a pointed finger I82 and a thread guide roller I83 which, together with a tension finger I84 act upon the thread in a manner hereinafter to be.

described. The finger I84 is secured. to an arm I 85 loosely mounted on shaft I14, the hub of arm I85 being mounted between fibre washers I86 serving to maintain frictional contact with looper arm I8I, the frictional means being maintained by the pressure of a compression spring I81 placed between a collar I88 fastened to shaft I-14 and a collar I89 loose on the shaft. The finger I84 is normally heldinoperative by a stop screw I90'adapted to engage a pin I9'I projecting from arm I85, screw I90 being adjustably fastened in a wing I92 of a holder I93 fastened to 1|. When the needle is transferred from the lower needle bar 64 to the upper needle bar 63, the latter grasps the needle and ascends by means of the cam actuated lever 50 to its up-position. The looper arm IBI, b means of its cam I10, is moved toward finger I84 as soon as the needle bar 63 has ascended sufficiently to permit it-to pass, arm I8I continuing to travel until its pointed finger I82 is about in alignment with the tip of finger I84, in which position it momentarily dwells. The needle bar then descends slightly and dwells and in so doing a loop is formed in the thread and substantially simultaneously arm I8I and finger I04 advance in unison, and arm I81 engages the front loop of the thread while finger I84 engages the rear loop of the thread, both members continue advancing and pulling the thread, for reasons to be described hereinafter. The advance of finger I84 is stopped when pin I9I abuts the wing I94 of holder I93, while arm.

I8I completes its full swing and carries the thread as shown in Fig. 1'1. Arm I8I immediately starts to retreat whereupon needle bar 63..

descends and-in so doing the extension 8010f its actuator member 65 engages the curved surface- I95 of finger I84, causingthe same to be re.-

turned to its starting position, as shown in Fig. 3.,

The needle bar 63 and arm I8I complete their A tension. spring I61 (Fig. l) stretched. between. a post I68" of arm I59 and a post, [69

travel andireturnto thepositions shown inFig. 3, it being understood that in. the meantime the needle has passed. through the work and is now g-rippedinthe lower needlebar 64, while bar 63,

looper IBI, and finger I84v retain their positions until the needle is again transferred to the upper needlebar- With needle 8I' grippedv in the lower needle bar 6.4; it descends by'meansof its camactuated lever 5-I to down position at the same time pulling the thread partly through the. work, whereupon it immediately ascends slightly and. dwells, this slight upward. movement tending to form a loop in the thread. At this time a pair of cam actuated gripper arms 200 and 20I (Figs. 11, 13 and 14) close around the needle and the looped portion of the thread to prevent unnecessary pulling of the stitch as a, thread puller 202' enters the front loop of the thread and starts to completely pull the free end of the thread through the work as seen in Figs. 15 and 18.

The gripper arms 200 and 20I are operated by acam 203adjustab1y attached to a cam 204secured to a shaft 205. Cam 203 (Figs. 1 and 11) has a cam track I99 engaging a cam follower 206 of a cam lever 201 mounted on a stud 208 carried by a holder 209 fastened on a support 2'I0. attached to frame 30. The upper end of cam lever 201 is provided with an open end slot 2iI'I' adapted to engage a pin 2 I2 in a bar 2I3 sliding in a runway 2I4 of a block 2I5 secured to member 62'. Since the bar 2I3- operates the gripper arms 200 and 20I in the same manner as in the co-pending application heretofore referred to, a more detailed showing of the same is deemed unnecessary.

The bar 2 I 3 when moved in one direction causes the arms 200and 20I to close about the needle BI and the looped portion of the thread and retain this position while the thread puller 202 engages the thread and advances it about the periphery of a drum. When the bar H3 is moved in the opposite direction, arms 200 and 20I return to their open position permitting thelower needle bar 64 to be moved upward.

The cam 204 is provided with a flange H6 and a shoulder 2I1 slightly smaller in diameter, adapted to receive the cam 203, said cam 204 also having at its end another flange 2I8 and shoulder 2I9't0 receive a cam 220. With the cams 203 and 220 properly set to fulfill their duty in timed relation with cam 204, they are clamped in position by means of bolts 22I. The cam shaft 205 is-supported at one end thereof in a bearing 222 of housing 31 (Fig. 1) and its other end in a bearing 223 of a stationary drum 224 secured to supports 225' attached to frame 30 as seen in Figs. 1 and 11. Shaft 205 is equipped with a gear 226 in mesh with an intermediate gear 221, mounted on a stud 228 supported by the wall of housing 3I (Figs. 1 and 2), which in turn is driven by the main gear 4|.

The gear 226 drives an intermediate gear 229 mounted on a stud 230 which meshes with a gear 23I integral with a gear 232 mounted on a stud" 233 which is supported in a bearing 234 of housing 3I; Gear 232 drives a gear 235 (Fig. 2)

mounted on a shaft 236 which is supported in;

246 and 24! forming a runway or track 242 engaging a roller 243 of an arm 244 which is clamped on one end of a shaft 245 supported by member 219; the opposite end of shaft 245 carries an arm 246 which at its upper end is provided with the thread puller 262. The motion imparted to arm 246 and its thread puller 292 by crank arm 244 is such that as the puller 202 advances its forward pointed end to engage the loop formed in the thread, as seen in Figs. 15

and 16, it moves slowly and engages the front loop of the thread and starts to pull the thread entirely through the work. Therefore the puller 202 does not act with such quickness in starting the pull of the thread through the work with a tendency to fray out the thread after a number of pulls or with a tendency to jerk and break the same but after the pull is started, the puller gradually increases speed when danger of thread breakage is past. The action of the thread puller, therefore, is to pull the loose end of the thread through the work with gradually increasing speed from approximately the time it first picks up the thread until it approaches the pick-up position, whereupon its advancing facility is gradually retarded.

Coacting with the thread puller, needle and needle bars, and acting to tension the thread properly and also prevent fouling of the thread or splitting by the needle, is a finger 241 (Fig. 13) which in the illustrated embodiment is provided with a hook at its free end and engaging and pulling the thread out of the path of the needle as it moves back and forth through the work. At the time of transfer of the needle from one needle bar to the other, the thread is held out of the position of the needle so that the thread is always clear of the needle and properly tensioned.

The motion of this finger is controlled by cams 248 and 249 (Fig. 12) secured to a vertical shaft 250 supported in a hub 25l of a bracket 252 fastened to th drum 224 (Fig. 1). The lower end of shaft 258 is equipped with a spiral gear 253 in mesh with a spiral gear 254 fixed on the cam shaft 205 (Figs. 1 and 11). Cam 248 (Fig. 12) engages a cam follower 2550f an arm 256 loosely mounted on a stud 251 carried by a lug 258 of bracket 252, the other end of arm 256 supporting a link 259 connecting to an arm 26!] which is attached to the lower end of a stud 26l (Fig. 11) loosely mounted in a hub 262 of a lever 263. The stud 26! (Figs. 11 and 12) terminates in a head 264 in which is adjustably clamped the finger 241 receiving oscillating motion from link 259 having an elongated slot 265 in which moves a stud 266 on arm 260. An adjusting screw 321 permits the finger 241 to be set in any desired position in order to engage the thread properly. A spring 261 is connected to arm 26D and has its other end attached to an adjustable rod 325 which allows spring 261 to be tightened or loosened by turning nut 326 located at the end of said rod for varying the amount of tension to be applied by finger 241.

Stud 266 is normally held by spring 261 in the position shown in Fig. 12 but can travel in slot 265 in order to tension the thread or prevent damage to the machine should any obstruction appear. Should spring 261 break or be rendered inoperative for any reason which might cause finger 241 to be located in the path of needle 8|, stud 266 will be engaged by the far end of the slot 265 as lever 256 swings in a clockwise direction on stud 251 (Figure 12) and finger 241 will be moved clear of the needle path and avoid having the needle ram into finger 241.

The cam 249 engages a cam roller 268 of an arm 269 which is integral with lever 263 loosely mounted on a stud 210 carried by lug 258, this cam importing somewhat of a closed or four-motion path of movement of the tension finger 241. A tension spring 211, stretched between posts 212 and 213 carried by lever 263 and arm 256, respectively, is provided to hold the cam followers 255 and 268 in engagement with their cam.

The finger 241 operates in conjunction with a guide plate 215 fastened to a throat plate 216 (Figs. 13 and 14) guide plate 215 being, provided with an opening 211 which is shaped more or less like a key slot. The opening'211 tends to guide the thread within the path of the finger 241 which may describe a path of movement corresponding somewhat to the contour of the opening. andinso doing the hooked end of the finger. 241. moves to engage the thread and pull the same laterally to one side of the needle thereby moving it out of the needle path, and holding the thread in that position, while the needle reciprocates, and then moves back to re-engage the thread on the next stitch.

The throat plate 216 is attached at its forward end to bracket 34 andits opposite end. is supported by a spacer 218 (Fig. 1) carried by member 2I5. Plate 216 is provided with a fill-in plate 219 (Fig. 13) and two similar plates (not shown) which are provided with slots to permit movement of the material feed members and also movement of the thread. The above mentioned plates are omitted in order to more clearly show the feed members I21 and 122 and the guide plate 215.

The cam 204 (Fig. 11) is provided with a cam track 280 engaging a cam roller 28! of a trip arm 282 mounted ona stud 283 carried by a lug 284 of member 215. The upper end of arm 282 engages the end of a plug 285 which is secured to the end of a spring tensioned rod 286 which terminates in a member 281-having a vertical eX- tending jaw portion 288. The pointed part 289 of a swinging arm 290 together with jaw portion 288 form a jaw adapted to clamp the thread and later carry the same upward to fulfill a duty presently to be described. The plug 285 and rod 286 slide in suitable apertures provided in arm 290 and aspring 291 confined in the aperture of the arm tending to normally hold the plug 285 against the end of arm 282. The swinging motion of arm 298 is accomplished by cam 220 having a cam track 292 engaging a cam roller 293 of a cam lever 294 loosely mounted on a stud 295 carried by a lug 296 (Fig. 1) of member 62. Lever 294 at its upper end supports a head 291 (Fig. 11) carrying a rod 298 connecting to a depending arm 299 of arm 290 which is mounted on a stud 369 carried by member 215. 4

The operation of the stitching of the work will now be described. With the needle 8| grasped by the lower needle bar 64 (Fig. 15), the needle bar descends its full stroke through the work, and immediately ascends slightly and dwells, the slight upward motion forming a loop L in the thread T. At this time the cam actuated gripper arms zoo and 201 (Fig. 19) close around the needle and the looped portion of the thread, to prevent unnecessary pulling. of the stitch in the work as the thread puller 292 (Fig. 15) enters the front loop of the thread and starts to pull the free end F of the thread through the work. As the puller 262 travels in a clockwise direction the front loop of the thread is caused to move along the tapered portion 30I which directs the thread into the groove 302 of the Puller, whereby the thread is placed over a ledge 303 of the gripper arm 200 as seen in Figs. 11 and 19. It will be noted that the vertical plane passing through the center of y the drum is disposed to one side of the needle path to give the operator more room beneath the sewing machine. Ledge 303 assists in the movement of the thread and makes it possible to guide the thread laterally and direct it more easily down onto the drum. With the thread partly around the groove 302 which may be cut at an angle, as seen in Fig. 19, the thread is caused to be placed against the edge 304 of the pointed portion 305 (Fig. 11) of a stationary guide member 306 at tached to member 2I5 as seen in Fig. 11, the edge 304 aligns the thread so as to pass through the space between jaws 288 and 289 (Fig. 11). As the puller 202 advances, the jaws 288 and 289 begin to close and when the puller reaches a position about as seen in Fig. 16, the jaws clamp the thread as seen in Fig. 19, the thread being still clamped by arms 200 and I. The thread A in the meantime is guided onto a shelf 30! of a drum member 308 which is bolted to a member 309 as seen in Figs. 15, 16 and 17. As the puller advances it positions the thread B in a groove 3I0 of member 309 and continues moving and completely pulls the free end F through the work at which time the arms 200 and 20I open, permitting the lower needle bar 64 to ascent. The operation of the thread puller is similar to that in my above referred to application in that it moves at a slow speed into engagement with the looped thread in order not to break the thread, then accelerates and moves more rapidly to complete the operation of pulling the loose end of the thread through the work. The clamped jaws 288 and 289 swing upwardly in unison with the ascent of the needle bar 64 and in so doing the thread A is caused to enterinto a. trap 3II of the stationary guide member 306 (Fig. 11), the finger 241 (Figs. 11 and 13) engaging the thread and pulling it out of the path of the needle and holding it there until the upper needle bar ascends.

The ascent of jaws 288 and 289 cause the thread A to be moved from shelf 30'I laterally and disposed in trap .3 in a manner similar to that set forth in my copending applicationmentioned above. With the needle grasped bythe upper needle bar 63, the same ascends its full stroke and immediately descends slightly forming a loop in the thread and dwells. Shortly before the ascent of the needle, the jaw 288 and 289 open, permitting the needle to pull a portion of the free end of the thread through slot .3I4. The arm I8I and finger I84 now move inwardly in unison and the finger I82 of arm I 8.! engages the front thread F of the loop and pulls the thread through slot 3I4. the arm advancing to a position shown in Fig. 17, finger I84 engaging the rear thread of the loop and moving; to a position shown in Fig. 17. In this position, the thread overlies the hooked portion of the finger thereby relieving the tension of the thread passing through the eye of the needle. Arm I.8I immediately starts to retreat, whereupon needle bar 63 descends and in so doing the extension 80 (Fig. 3) of actuator member 65 engages the curved portion I95 of. finger I84 causing. the same to be returned to its starting position as seen in Figs. 3 and 16. The jaws 288 and 289 startdescending with the descent of needle bar 63 and are returned to their starting position. The tension finger 241 (Fig. 13) engages thethread and moves it out of the path of the needle 8| a it descends to perform its stitch and be transferred to the opposite needle bar.

Before each transfer of the needle, the feed arm I22 and feed foot I2I advance the work one stitch length. The presser foot I20 at such time is raised sufiiciently to permit the work to be moved, when the material feed reaches the end of its stroke the presser foot descends clamping the work against the work table and the arm I22 descends slightly and returns to its starting position at which time it is again raised to engage the work. The feed foot I2I is advanced b the material feed arm I22 and when the latter descends, the feed foot, by means of its mechanism heretofore described, is raised permitting a spring actuated arm 3I6 (Fig. 3) to return it to the starting position. Arm 3I6 is loosely mounted on a stud 3I'I carried by a lug 3I8 extending from bridge 51, a spring 3I9 coiled about the hub of arm 3I6 having one end arrested in a hole in lug 3I8 and its other end passing through a hole provided in the arm.

It is to be understood that the form of my invention, herewith shown and described, is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of my invention, or the scope of the subjoined claims.

What is claimed is:

1. In a sewing machine of the class described. the combination with alternately moving needle bars, of a needle, means for alternately connecting said needle with said bars for projection with a thread through work to be sewed, means for moving the thread out of the path of movement of said needle including a finger arranged to engage said thread, a support for said finger, and means for moving said support to move said finger in a substantially closed path substantially at right angles across the path of movement of said needle into and out of thread engaging position.

2. In a sewing machine of the class described, the combination with a pair of aligned alternately operating needle bars, of a needle, mechanism for reciprocating said bars to alternately connect said needle with said bars for projecting said needle and a thread back and forth through material to be sewed, a support, an arm mounting said support for movement, a finger carried by said support, and driving means coacting with said support and operating in advance of the movement of said needle to move said finger at substantially right angles across the path of said needle into and out of thread engaging position.

3. In a sewing machine of the under and over type stitch, a tensioning device for preventing fouling of the thread by the needle, comprising a support, a finger mounted on said support. mechanism for moving said support to move said finger in a closed continuous path into engagement with the thread to tension it in the work, in-

closed path into and out of tensioning relationship with said thread, including means for maintaining said finger in engagement with said thread during a portion of each stitch forming cycle, said last-named means also including means for moving said finger out of engagement with said thread.

5. A thread tensioning device for a sewing machine, comprising a table, a thread guide formed in said table, a traveling support mounted beneath said table and guide, a finger mounted on said support and arranged to engage said thread, and means for moving said support to move said finger relative to said guide in a closed path to tension said thread and maintain it out of the path of a needle.

6. A thread tensioning device for a sewing machine having opposed needle bars and a needle which is projected back and forth with a thread through material to be sewed, comprising a support, a shaft mounting said support, a tension finger carried by said support, and projectable into position to engage said thread, a support actuating arm, a finger actuating lever, a second finger actuating lever, a link connecting said levers, and cams coacting with said arm and said levers for moving said finger in a closed path into and out of thread engagement.

7. In a sewing machine a needle bar carrying a needle and thread for sewing, a work table having a thread guide formed in said table, and provided with an irregular opening, a tension finger located beneath said table, and means for moving said finger in a closed path conforming to the shape of said guide opening for tensioning and holding the thread out of the path of said needle.

8. In a sewing machine, a needle bar carrying a needle and a thread for sewing, a work table having an irregularly shaped thread guide formed therein, a tension finger located below said table and projecting into position adjacent said guide to engage said thread, and means for moving said finger to engage said thread to tension the same and move said thread in said opening out of the path of said needle.

9. In a sewing machine having a needle bar holding a needle and a thread for sewing, a work table having a thread guide provided with an opening formed therein, a tension finger provided with a thread engaging point located to engage said thread, means for mounting said finger for translatory movement of said thread conforming substantially to the shape of said opening in said guide, and means for maintaining said finger stationary during a part of each sewing cycle of said machine to position said thread out of the path of said needle.

10. In a sewing machine having a needle bar holding a needle and a thread for sewing, a ten sion finger provided with a thread engaging point located to engage said thread, means for mounting said finger for translatory thread engaging movement, and means for maintaining said finger stationary during a part of each sewing cycle of said machine to position said thread out of the path of said needle, said last-named means including means for moving said finger to free said thread from engagement with said finger.

11. In a sewing machine having a vertical operating needle and a work table, a thread displacing finger, and means for moving said finger in a substantially horizontal plane and in a closed path beneath said table to maintain a thread clear of the needle and to tension the thread during formation of the stitches.

12. In a sewing machine provided with a needle bar and a needle'for projecting a thread through material to be sewed, a member movable m a substantially horizontal plane into and out of engagement with said thread, and mechanism for moving said member across the path of travel of said needle to pull said thread to tension it relative to the material and to hold it out of the path of said needle each time said needle is passed through the work.

13. In a sewing machine provided with a needle bar for projecting a needle and thread through work to be sewed, a work table arranged to support material to be sewed, said table being provided with a thread guide, a member located beneath said table and movable in substantially a horizontal plane for engaging said thread, and means for driving said member in timed relation to the movement of said needle to pull said thread laterally within the limits of said guide and maintain said thread out of the path of said needle during its movement through the Work.

14. In a sewing machine having opposed needle chucks and a double pointed needle which is projected back and forth with a thread through material to be sewed, a yieldingly mounted thread guiding and tensioning device constructed to engage said thread, means for moving said device into engagement with said thread and for translating said thread after engagement therewith out of the path of movement of said needle and maintaining it clear of said needle, mechanism coacting with said device for properly tensioning said thread, and means for adjusting said mechanism to control the tension exerted thereby within given limits.

15. In a sewing machine having opposed needle chucks and a double pointed needle which is pro jected back and forth with a thread through material to be sewed, a yieldingly mounted thread guiding and tensioning device constructed to engage said thread, means for moving said device into engagement with said thread and for translating said thread after engagement therewith out of the path of movement of said needle and maintaining itclear of said needle, mechanism coacting with said device for properly tensioning said thread, and means for adjusting said mechanism to control the tension exerted thereby within given limits, said means including a spring actively associated with said device, a control member connected to said spring, and means for moving the control member relative to said spring to vary the tension exerted by said spring on said device.

16. In a sewin machine having opposed needle chucks and a double pointed needle projected back and forth with a thread through material to be sewed, a thread guiding and tensioning device, and means for moving said device at regular intervals in a closed path, part of said path passing through the range of movement of the needle for holding the thread clear of the needle and tensioning said thread.

17. In a sewing machine having opposed needle chucks and a double pointed needle projected back and forth with a thread through material to be sewed, a thread guiding and tensioning device, means for moving said device at regular intervals in a closed path, part of said path passing through the range of movement of the needle for holding the thread clear of the needle and tensioning said thread, and means for varying the position of said device relative to the thread to be engaged thereby.

18. In a sewing machine having opposed needle bars, a double pointed needle; means for moving said bars to project said needle 'back and forth with a thread through material to be sewed, a

thread guiding and tensioning device, means for moving said device at regular intervals ina closed unidirectional :path, part of said path passing through the range of movement of the needlefor holding the thread clear of the needle and for tensioning the thread.

19. In a sewing machine of the under andover =stitchtype, the combination with a pair of alternately operating needle bars and a double pointed needle; of means for alternately connecting said needle with said bars for'projecting a thread havingafixed and a loose end through-material to be sewed;.a pair of thread gripping jaws located adjacent one of said needle bars, one of said jaws being provided with a reduced thread guiding portion, means for operating said jaws to grip the thread against movem'ent relative to said needle atthe conclusion of the stitching operation, and

'means for pul1ing the loose end .of'said' thread ing said jaws in timed relation to said bar for gripping said thread.

' 21'. In a sewing machine of the class described,

th combination with a needle and a needle bar,

. of a thread receiving drum, said needle bar being located so as to move a needle in a path disposed to one side of the vertical plane passing through the center of said drum, a thread gripping 'member positioned adjacent saidneedle bar, and a thread guide formed adjacent the end of said gripping member.

22; In a sewing-machine, a needle bar carrying .a'needle and a thread'for sewing, the combination with a pair of gripper arms located adjacent said needle bar, one of said arms being provided with a cut-away portion,imeans for operatingsaid arms to grip the needle and thread at'the conclusion of the stitchingcycle, and means for pulling the loose end of said thread past said cutaway portion.

-23. In a sewing machine, a thread receiving drum-and a thread puller comprising;- a thread pullingmember, a shaft, an arm mounting said :thread-puller fixed to said shaft, '3, crank arm mounted on said shaft, a roller mounted on said crank arm, a thread puller driving member, a

track on said member engaging said roller,and means fordriving said thread puller driving member tof'cause'said track and rollerto coact and rotate said puller at varying "speeds.

v '24. The method of controllingathreadhaving a loose and a fixedend being projected through erally beneath said 1 material in asubstaritially -material by -a needle in forming overand under stitches "in said material which comprises moving a predetermined limited portion of said thread extending within the range of the path of movement of .the needle laterally beneath the material and at substantially a right angle across the path of movement of said needle to locate said predetermined limited portion of said threadout of the path of movement of said needle, positively holding 'saidengaged portion of said threa'd'out of the path of the needle while the thread is being projected through the material to form a stitch and pulling the loose end of the thread through'said material during the formation of each stitch.

25.. The method of controlling the position of a thread being projected by a needle in a vertical plane back and forth through material to be sewed in forming over and under stitches which comprises moving said thread laterally with respect to said needle beneath said material and at substantially right angles across the path of said needle after it has been projected through said material to-locatesaid thread out of the path of travel of said needle, and holding said thread beneath said material clear of the path of said 'needle,'and applying tension thereto While said needle is again projected through said 'work to form another stitch.

26. The method of controlling a portion .of a.

thread being projected through material by a needle in forming over and under'stitches which comprises moving said portion of said thread laterally beneath said material and at substantially right angles across the path of said needle to dispose said portion of said thread out of the path of movement of said needle, and positively holding said portion of said thread out of the path of said needle while said needle isbeing projected through said material to form a stitch.

' '2'7.i-The method of controlling a thread being projected in one 'plan'eback and forth through material to be sewed in forming over and under stitches comprising engaging thethread beneath said material in a direction normal to said plane, moving said thread laterally beneath said material'in a substantially horizontal plane to a positionout of the path of movement of said needle and remote from the position where 'it wasfirst engaged, holdingsaid thre'adbeneath s'aid material at said remotepositionduring a partial forming of a stitch, and then releasing said thread.

28. "The method of controlling a thread being projectedby a" needle through material to be sewed in' forming .over and under stitches comprising translating'a portion of'said thread lathorizontal plane away from the pointof stitching andoutoi the'path of travel of 'said needle, ten- -sio'ning'- and' holdingsaid thread in said lateral position during "a part" ofthe stitching cycle, and

then'releasing" saidthread.

" CARL JOHNSON.

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