Патент USA US2128120код для вставки
Aug. -23, 1938. - N. v, cHRlsTl-:NSEN ET A1. 2,128,120 ' SEWING MACHINE Filed Jan. 25,»1936 _ , $5 Sheets-Sheet lv __ Charlas-171mm@ / l Aug. 23,' 1938. N. v. cHRlsTENsl-:N ET A1. ' 2,128,120 SEWING MACHINE Filed Jàn. 25, _ 19:56 :5 sheets-sheet 2 WTORNE YS. Aug. 23, 1938. N. v. cHRlsTENsEN ET AL 2,128,120 SEWING MACHINE Filed Jan. 25, 1956 l3 Sheets-Sheet 5 BY . v il TOR/VAE YS. >2,128,120 Patented Aug. 23, 1938 UNITED STATES 'PATENT OFFICE 'SEWING MACHINE Norman V. Christensen. and Charles F. Rubel, Chicago, Ill.. minors to Union Special y Machine Company, Chicago, Ill., a corporation of Illinois - , Application .Imam z5, 193s, serial No. V60,764 'z claims.y (ci. 11e-_197) - This invention relates to sewing machines; and it `has reference more particularly to a. chain „ stitch sewing machine of the type wherein the rotary main or driving shafts from which the '5' needle, looper and i’eed mechanisms all derive their movements are journaled in horizontal arms ` overhanglng ilat oblong bed plates or work sup ports. Such machines are extensivelyused in the manufacture of bags of burlap, canvas> and 10 >the like as well as in other connections. The aim of our invention is to enable operation of sewing machines of the type specifically re Ierred to at higher speeds than possible hereto fore, with a view toward obtaining increased u production from them. . This objective we realize in Practice, as here inafter more fully described, by utilizing light rotary parts to the utmost extent, and translat ing the rotary motion of such parts into recipro in a copending patent application Serial No. 58,672 filed on Jan. 1_1, 1936, by Norman V. Christensen, one vof the present applicants, may be used. ’Journaled in bearing bushings 5 and 6 set into the hollow of the overhanglng arm 3 is 5 the main or drive shaft 1 of the machine, the rear end of said’ shaft extending through the bearing 6 to the exterior where it is provided with a combined hand and belt wheel 8 so that the machine may be operated either manually or 10 by power. As shown, the bearings 5 and 6` have oil ports 9 and I0 which'respectively register with vertical oil ducts il and i2 accessible at the top of the overhanging arm 3. Guided i’or vertical reciprocation inupper and lower bushings y|3’and 15 it set into the head t, is a vertical bar i5 which carries the needle it., Up and down movements are imparted to the needle bar ib by means which includes a dynamically-balanced cranlr member . i'i whereof the cranlr pin it is coupled, by means 20 of a link it, with a pin it projecting rearward feed elements, etc.) which require reciprocation from a split collar il which is secured to said through provision of correspondingly iight, struc- . needle bar near the top within the hollow of the turally-reñned intermediate connections which head t, by a” clamp screw il. The projecting end 25 are dynamically balanced and smooth in'- their of the pin 2t is ñattened as at il to engage a 25 Y20 catory motion at points or regions local to those elements (e. g. the needle, looper or loopers, ‘action so that noise, vibration and wear are re-, ` vertical guideway it within the hollow head t, and is thereby steadied in its movements. Free to rotateon the pin id is a ball it which engages appear :from the following detailed description the spherical cavity oi a split bearing boss il 30 of the attached drawings, wherein Fig. I is a . at the lower end oi the linlr iii. The cap piece 3o longitudinal sectional view of a top rotary shalt it oi the bearing boss il is formed with a scoop ñat bed sewing machine conveniently ems 2d which dips up lubricating oil from a small well tu in the bottom oi the head t and conducts our invention'. it to the surface of the bali it, aportion oi such Fig. il is a view of the machine in end eleva :wlw-1 ` , ,_ @ther objects and attendant advantages will 35 tion looking from the lei't of Fig. I. oil ñnding -its way to the pin it by way oi one or ' Y: ' «' Fig. m show's'the needle arm oi? the machine in plan; and . more radial ducts ti in said ball. 'lfhe described construction oi the link it constitutes one of the Fig. il! is a plan sectional viewol the machine features of the present invention and is advan- y taken as indicated by the arrows IV--IV in Fia. l. tageous in that said link and its connections are 40 As herein illustrated, the irame ol our improved "rendered sell-aligning, Seli-onlne and smooth , sewing machine comprises a nat horisontal ob acting, with preclusion oi binding and heating longbed plate or work support i, with an inte oi the end bearings of said linis when the machine grally formed hollow standard 2 opstanding from one end thereof and sustaini a hollow over 45 hanging arm i above said work support, said arm terminating at its free end in a head il. The machine is primarily designed lor mounting- upon the top oi au operetor’s table T (Fig. l) with the bed plate or worl: support l suhstantially hush, g, and the parts ndant therefrom projecting down through an opening Q in the table. in instances where it is desirable to have the bed plate i elevated, or when the machine is to be sustained on a narrow plank or beam as in bag factories, g, a mounting or base such as shown and described is operated at high speeds. if there should be any tendency oi either one oi the bearing surfaces oi the ball it to sticls, the other oi said surfaces uwill obviously continue to function as a pivot. . The vertical presser bar di of the machine is guided near the bottom in a dant bearing projection dit oi the head d, and is held against rotation through engagement oi the lateral pro- r ¿lection Bil of a collar it thereon, in a vertical guide tt at one side of said head. The upper end oi the presser bar t2 is conñned to slide in a screw bushing 37 threaded into the upper part oi the bead il,-said bushing bei longitudinaliy/ 2 2,128,120 slotted as'at 33. The presser bar 32 is acted upon by a double leaf spring 39, of which the forward end extends through" an opening ¿i0 in the back of the head Ll (Fig. III) and into the slot 38 of the bushing 3l to engage the rounded top of said bar, seev Fig. II. The rear end of pendant bearing lugs l0, "il of the work support i, and, in `eñect, is a coaxial continuation of the transmission shaft 50. .incident to assem bling the >machine7 the collar 58 and the bush ing 5| are mounted on theshaft 50 and the right hand end of the latter is inserted- through the the spring 33 is apertured as shown in Fig. III bearing boss ‘l2 on the oil sump 53, whereupon to engage an anchorage stud „projection ¿il on said bushing is pushed into place and secured by the overhanging arm 3. The pressure of the spring 39 is regulatable by a set screw ¿l2 thread ed in a bracket lug d3 at the top of the arm 3; the set screw shown at W3, see Fig. I. The con struction of the lower shaft of the machine from the two parts 50 and £53 as shown and described is advantageous in that it facilitates assembling of the machine, and also in that it aüords a separable crank ä'l at the juncture between said sections.> Cooperating with the needle i5 beneath the Work support i of the machine, is a looper 'M which is carried by a vertical arm 'l5 fulcrumed on a stud ‘i6 projecting from the looper rocker lll which is secured by set screws “i8 to a rock 20 shaft ’i9 having its ends journaled in bushings and a jam nut iid functions as a means for hold ing the set screw in adjusted positions. Due to the influence of the leaf spring 39 upon the bar 32, the presser foot ¿l5 at the lower end of the latter is maintained in yielding engagement with the fabric being sewed in the machine. In order that the presser foot |55 may be raised clear of the work support i when desired or 20 required, a lifting latch lever 08 is provided, said lever being fulcrumed to swing about a screw dl engaged in the front of the head él, and hav ing a cam surface ¿38 to coact with a stud pro jection H9 on the collar 35 aiìxed to the presser 25 bar 32, see Fig. II. Extending longitudinally of the machine be neath the work support l in parallel relation with 80 and 8i respectively set into the bearing lugs l@ and "il, rI‘he shaft 39 is rocked through the medium of an arm 82 clamped thereto and con nected to the strap 83 of an eccentric 34 on the 25 supplemental shaft 68, see Figs. I and IV, with resultant impartation to the looper of its needle the main shaft 'i is a transmission shaft 50, -avoiding movements. The holder or carrier 'l5 which, at its rear end, is journaled in a bushing for the looper il is oscillated about the fulcrum 30 5| set into the front wall 52 of a lubricant sump 'i6 -in the performance of its loop taking func 53 integrally formed with, and depending from said work support. As shown in Fig. I, the lubri cant sump 53 is in direct communication with the hollow of the standard 2, and closed at the 35 bottom by a removable plate 55. The shaft 50, it will be noted, extends into the lubricant sump 53 and to its end is secured a helical gear pinion 56, the hub 51 of which abuts one end vof the bearing bushing 5| while a collar 58 abuts against 40 the other end of said bushing to hold said shaft from shifting endwise. The gear pinion 56 is tions through a horizontal link 85 which _has split bearings 86 and 81 at its opposite ends respec driven, through an intermeshing idler gear wheel ball end 98 and which is coupled with the crank pin 61 on the transmission shaft 50, by a link 59, from a helical gear pinion 60 secured on the main shaft 1 directly adjacent the bearing 6 of 45 the latter.y The idler gear 59' is free to rotate on a fixed transverse shaft 6| within the hollow of the standard 2, and the thrust thereof in opposite _directions is opposed by collars 62 and 63 on said shaft 6| abutting opposite faces of 50 the hub 64 of said gear wheel. The gear train 56, 59 and 60 is lubricated through splash oil carried up from a supply within the sump 53. In practice, the idler gear 59 is made from suitable sound and wear absorbing material, and is pref 55 erably so proportioned with respect to the pin ions 56 and 60 that theA points of contact thereof with the latter gears constantly change with re sultant uniform distribution of the Wear. The communication of motion from the upper or main shaft 'l to the lower or transmission shaft 50 is thus effected smoothly, positively and noise ' lessly. The gear drive herein`> shown and de scribed is the same in principle and operation as that disclosed in applicants’ copending -applica 65 tion Serial No. 670,186 filed on May 9, 1933. At its left hand end (Figs. I and IV), the transmission shaft 50 is integrally formed with a pair of spaced crank heads 65, 66 with a con necting ball crank pin 61, from which the looper 70 mechanism of the machine receives its move ments as >will be presently explained.- The ter minal head 65 has a socket to receive the con tiguous end of a supplemental shaft 68 which is made fast by screws 69. As shown in Fig. IV. tively engaging a ball stud 88 on said 4carrier 'l5 and a similar ball stud 89 on an arm 90 extend ing upward from an oscillating sleeve 9|. As shown, this sleeve 9| is aiiixed to a transverse rock shaft 92 whereof the ends are journaled in bearing »bushings 93. 94 set into spaced lateral projections 95, 96 of the bearing lug 'il herein before referred to. The oscillating sleeve 9| also has a horizontal arm 91 which terminates in a 99 also formed with split bearing ends |00, |0|,. to respectively engage said ball and the crank pin. By employing balanced parts with ball ‘joints in the looper mechanism just described, and through provision of the crank pin 61 in lieu of an eccentric such as is ordinarily used in machines of this type, friction and wear is re duced to a minimum so that the movement of the mechanism is rendered smooth and easy and noiseless. . . The means provided for progressively advanc ing the fabric in the machineincludes a feed dog |02 which, as shown in Fig. II, is secured, with capacity for vertical adjustment, to a feed bar |03 `by means of a screw |04. Fixed in a boss |05 at the rear end of the feed bar |03, is a trans-l verse pin |06 whereof the ends engage spaced bearing bosses |01, |08 of a yoked rocker |09, which, in turn, is secured to a rock shaft ||0 whereof-the ends are jo‘urnaled‘respectively’iîf the bearing ||| of the lug 10 and another bear ing lug ||2 pendant from the work support |, said rock shaft being held against shifting axially by collars ||3, Ill thereon'which respectively abut the lugs | I | and- ||2 at their inner sides, see Fig. IV. Secured to the outer end of the rock shaft ||0, preferably by welding, isa horizontal C arm ||5 which reaches forwardly and which atv .its outer end' has pivotal connection at ||6 with the lower end of a vertical link ||1 whereof the upper end` is split to clamp a bushing ||8 engag 75 the supplemental shaft 68 is journaled in spaced Y ing a crank pin ||9 on a crank disk'l20 amxed 75 3 2,128,126 to the outer end of the supplemental shaft 00. Thus,- during the rotation of the supplemental shaft 68 back and forth feed movements are in duced in the feed dog |02.» 'I'he pin |i0 is ra dially adjustable on the crank disk |20 so that the feed stroke of the dog |02 can be varied. The lift movements are imparted to the feed dog |02 by ¿means of an eccentric |2| on the supple mental shaft 6B, the strap |22 of which is pivot 10 ally connected at |23 to the downwardly and .forwardly curved arm projection Wt of the feed bar |03, see Fig. II. The feed mechanism just described isv generally similar to that featured in U. S. Patent No. 1,817,727 to Wohlpart, and, is hereinafter claimed only in combination with the' other »and cooperating mecha nisms of the machine. It is to be particularly noted however that in the present instance, the feed rocker shaft lit passes through a hearing in 20 the lug iii disposed between the feed rocker itt and the arm H5. This arrangement is advan tageous in that it precludes exertion of side thrust or torsion against the feed rocker idd and thus eases ,the action of 'the feed mechanism. In order that tight stitches may he formed hy 25 the machine, there is provided a nipp‘er or inter mittent tension means for the needle ihre, this means being shown in Fig. I as comprising a ver tical sleeve W5 which is fast in a boss t28 at the 30 top of the overhanging arm 3, and which is sur mounted by a regulatable tension device it'i adapted to be actuated by an eccentric t28 on the main shaft 'I through a thrust pin or plunger itt guided in said sleeve. Also, during the sewing, the slack of theviooper 35 „thread is absorbed> by a take-up device which is generally designated by the numeral |30 in Figs. I and IV. This take-up comprises a rotary cam disk |3| which is secured to the supplemental shaft 03 and which projects through a slot |32 in an inclined guard plate |33 suitably secured beneath the work support of the machine and overreaching said shaft. Fastened to the guard plate |33 by screws |33 is 'a upshaped hold-_down tongue |30 of wire (between which and the plate, 50 crank; and a connection between the needle har and the pin of the crank including a link, a lat eral pivot on said bar in engagement with a boss at one end of the link, a’hall free to rotate on the crank pin as an axis and engaging a spherical C1 bearing surface in a hoss at the opposite end of the link. ` - ' > , 2. In a sewing machine, a frame with a work supporting plate and a hollow overhanging arm sustained by a hollowvstandard at one end of said plate; a rotary shaft journaled within the hollow of said arm; a needle har conñned to vertical reciprocation in a head at the free end of the overhanging arm; a balanced crank at the forward end of the shaft; a crank pin on.,said crank; and a connection hetween the needle bar and the pin of the crank including a iaterai stud on said roar in engagement with a bearing hoss at one end of the link, a hall free to rotate on the crank pin and engaging a spherical hearing 20 surface in a `boss at the opposite end of the link, the last mentioned hoss having a scoop projection adapted, during rotation of the crank, to scoop up oil from a well within the head for lubricating the hall and the crank pin. 25 3. In a chain stitch sewing machine, a frame with a work supporting plate and a hollow over hanging arm sustained by a hollow standard at one end of said plate; a pair of longitudinal shafts, one journaled within the hollow arm, and 30 the other journaled beneath the work supporti plate; a train of intermeshing gear wheels form ing the drive connection between the two shafts, said gear wheels being enclosed in the hollow of the frame standard and a counicating oil 35 sump pendant lfrom the work support; a needle bar conñnïed to vertical reciprocation in a head at the free end of the overhanging arm; a coop erative looper, and a feed element below said Work support; means adjacent the forward ends 40 of the two shafts whereby their rotary move ments are converted respectively into recipro catory movements of the needle- bar, and into oscillatory and reciprocatory movements of the looper and the feed dog; a tensioning device for 45 the llooper thread passes), and thread >guides |31 the needle thread; and a rotary cam on the >at opposite sides of the slot in said plate. The upper of the two shafts for actuating the‘tension ing device to intermittently apply tension on- rotary take-up just described corresponds incon struction and principle of -operation with that forming the subject matter of a copending appli ’ cation Serial No. 24,495, filed on June l, 1935 by Charles S. Thompson.` . From the foregoing it will be seen that in 'our improved sewing machine, we have utilized but 55 two rotating shaft‘s which are interconnected hy a gear train drive system, and from which the rotary movements are translated, through light vand dynamically balanced anti-friction parts, >into reciprocatory movements oi' the needle, the the thread. ' 4. In a chain stitch sewing'machine, aframe 50 with a work supporting plate and a hollow over hanging arm sustained by a hollow standard at one end of said plate; a pair of longitudinal shafts, one journaled within the hollow arm, and the other iournaled beneath the work support 55 ing plate; a train of intermeshing gear wheels forming the drive connection between the two shafts, said gear wheelsl being. enclosed in the hollow of the frame standard and a communi looper and the feed dog, at regions local to these eating oil sump pendant from the work support; he cooperating elements. In this way, we have a needle har confined to vertical reciprocation in edêctively avoided strains and restraints in the a head at the free end of the overhanging arm; a moving parts such as would result in excessive cooperative'iooper, and a' feed element loelow heating to theadvantage that the machine can said work support; means adjacent the forward ends of the two shafts whereby their rotary move 65 “ be operated at much higher speeds than hereto ments are converted respectively into _recipro fore attainable. Having thus described our invention, we claim: catorr movements of the needle bar, and into l. In a sewing machine.' a frame with a work oscillatory and reciprocatory movements of the looper andthe feed dog; and tension devices supporting plate and a hollow overhanging a 70 'sustained by a hollow standard at one end of said respectively for the needle and looper threads plate; a rotary shaft journaled within the hollow controlled hy rotary means respectively on the of said arm; a needle bar confined to verticali reciprccation in a head at the free end of the overhanging arm; a counterbalanced crank at i, the forward end of the shaft: a crank pin on said upper and lower Mits. 5. In a chain stitch sewing machine, a fre with a work supporting plate and a hollow over hanging arm sustained hy a hollow standard >at 75 aieaieo one end oi said plate; a pair oi icngitudinai shafts, one journaieci within the hollow arm, and the other journaled beneath the work support plate; a` needle operated from above the Weil;u supporting plate; compiementai stitch-forming mechanism cooperating with the needle below the ing plate; a train oí’ intermeshing gear wheels Work-supporting plate; and a longitudinal shaft composed ci’ two axially-aligned sections with a forming the drive eonnectionhetween the two shafts, said gear wheels beine enclosed in the ' crank formes“-h at one enti. of one of saisi sections "noilow of the frame standard and a. communicat ing oil sump pendant from the Wort: support; a needie bai' confined to verticai z'ecipi'ocation in a '10 head the free end. of the overhanging e, cooperative looper, and a feed element ioelow saisi work support; means adjacent the forward ends of the two shafts wi'iese‘oy their" rotai‘y inove« ments are ccnveiteci sespectiveiy into i'ecipi‘om eatery movements of the needle bei“, and into oscillatory and ieciprooatoiy movements oi’ the iooper and the feed doe; a tensioning device ici`> the >the needle two shafts thread; for aactuating rotary cam theon tensioning the upperde» vice to inte'fmittentiy appiy tension on the needle thread; and a rotary tension device for the loopei.e thread actuated from the ioweil sloai'tq e. ‘in a sewing machine„ Work-supporte@ actuating the complementai stitch-forming mechanism, and affording connection for the con» tiguous end oi the othei‘ shaft section. 7., En a sewing machina a work-suppoi‘tine plate; a needle operated. iron?. above the worth supporting plate;- oomplementai stitcndoi'n’iing; >nfieciianisnri ccopeieting with the needle "neiow the Wori§~supporting plate; anni a longitudinsi sine-ft composed of two axially-aligned sectione with a orfani; termed at one enc?, oi' one of saisi sections for actuating the complementai :stitchu forming mechanism, and having a socket within which the contiguous ene. of the other sec~ tion is received and secui‘eeî.. NORTMÃN V. CHRÍSTENSEN. CHARMS F. RUBEL.