US1989919A

US1989919A - Sewing mechanism

Info

Publication number: US1989919A
Application number: US506791A
Authority: US
Inventors: Byron F Everitt
Original assignee: Briggs Manufacturing Co
Current assignee: Briggs Manufacturing Co
Priority date: 1931-01-05
Filing date: 1931-01-05
Publication date: 1935-02-05
Anticipated expiration: 1952-02-05

Description

Feb. 5, 1935. B. F. Evl-:RITT

SEWING MECHANISM Sheets-Sheet 1 Filed Jan. 5, 1931 ATTORN EYS Feb. 5, 1935.

B. F. EVERITT n SEWINGfMEGHANIsM Filed Jan. 5, 1931 9 Sheets-Sheet 2 MMMWMM ATTORN EYJ' Feb. 5, 1935. y B F, EVERITT 1,989,919

` SEWING MECHANISM Filed Jan. 5, ,-1931 9 Sheets-Sheet 3 INVENTOR ATTORN EY:

Feb- 5, 1935- B. F. EvERlT-r 1,989,919l

SEWING MECHANISM Filed Jan. 5, 1951 9 Sheets-Sheet 5 92 78 2 82 y (Vf-7 INVENT Feb. 5, 1935. B. F. Evl-:RITT

SEWING MECHANISM 9 Sheets-Sheet '7 Filed Jan. 5, 1951 Feb. 5, 1935. B, F. EVE'RITT 1,989,919

l SEWING MECHANISM Filed Jan. 5, 1951 9 sheets-sheet 8 IWI/)777) ATTORNEYS Feb. 5, 1935. B. F. l-:vERlT-r SEWING MECHANISM Filed Jan. 5, 1951 9 Sheets-Sheet 9 ATTORNEYS Patented Feb. 1935 UNITED stares SEWING MECHANISM Byron Everitt, Detroit,

Mich., assigner, ,by

mesne assignments, yto Briggs Manufacturing Company, Detroit, Mich., a corporation of Michigan Application January 5, 16 Claims.v

This invention vrelates to a sewing mechanism and method, and more particularly to a. method of and apparatus for manufacturing upholstery for seat cushions and the like. vStructurally, the invention has particular referenceA to an im? proved. sewing mechanism employing a pair of threaded thrusting and retracting needles and a double reciprocating looper.

One of the important objects of this invention is to provide a sewing mechanism in which the needles have av differential movement during their thrusting and retracting kmovement so as to decrease the increment of time during which the needle is engaged with the seam ridge. 'Cooperating with the needlesoi the sewing mecha nism is adouble reciprocatinglooper having por tions which takerthe loop .from each needle and preserve or hold the loop for engagement by-the other needle upon its thrusting movement.

As in the companion cases previously ymentioned, the instant inventiony contemplates stitches extending from the exterior of thetubes or tubular upholstery into the -interior ofthe tubes where the stitches are completed. To this end the thrusting and retracting needles arefarranged exteriorly of the tubes and are thrust through the seamridges intothe interior of the tubes where theflooper works, the looper coop erating therewith to complete the stitches inside the tube. .i

The several objects, advantages and novel de-y tails of constructionoi this invention together with-the manner in which the method ispracticed will be made more apparent as this description proceeds, especially when oonsidered'inico'n.- nection with the `accompanying drawings, wherein .Y Y

Figure 1 is a sectional side elevational View of a sewing apparatus constructed rin accordance with this invention; y f

Figure 2 is an enlargedvfragmentary vertical longitudinal sectional view showing the means for presenting the iinish and lining fabricszto the sewing mechanism together with the Vposition and location of the sewing mechanism with respect thereto;

' Figure 3` is a detail horizontal fragmentary sectional view taken substantially on the plane indicated by line 3-3 in Figure 2 looking in the direction of the arrows; Y

Figure 4 is an enlarged vertical fragmentary sectional view takensubstantially on the plan indicated by line 4--4 in Figure 3; n

Figure 5 is an enlarged sectional elevational View of one of the sewing heads;

1931', serial No. '506,791

Figure' is an enlarged fragmentary sectional elevational View. 'taken substantially on the plane indicated by line 6-6 in Figure 2 showing the relation of one .of the needles of the sewing head to the seam ridge; I

Figure 7 is a sectional elevational view taken substantially onthe plane indicated byline 7--7 in Figure 5 looking'inthe direction of the arrows;

Figure 8 is La vfragmentary vertical sectional view through one of the sewing heads taken substantially on the plane indicatedby line 8-8 in Figure Y9; l

Figure 9 is a sectional View taken substantially on the plane indicated by line 9 9 inAFigure 8;`

Figure 10 'is an enlarged fragmentary horizontal sectionalview taken substantially on the plane indicated by line 10A-10 in Figure 1;

' Figure 11 is a sectional elevational View taken substantially on the -plane indicated by line 11-11 inzFigure 10;

Fig-ure 12 is ahorizontal sectional elevational view taken substantially Von theY plane indicated by line 12.--12 in Figure 117V;

Figure 13-isa detailseotional elevational view taken substantially on the plane indicated by line 13-'l13 in FigureA 12;` k g Figure 14 is an enlarged top plan view of the looper.; f c

. Figure 15 is an enlarged side elevational view of the looper; Y

Figure 16 is a sectional View.v taken substantially onthe' plane indicated by line 16-16 in Figure 15; f

aY sectional view taken substan" tially on the planek indicatediby line 1'7-17 in Figure 15; n .l

Figures 18a and 18h are semi-diagrammatic elevational views respectively .of the two sewing heads of the sewing mechanism as seen respec tively on theA lines 18a-18a and 18h-18h looking in the direction of the arrows in Figures 19, 20, 21 and 22 respectively;

Figure y19 is a semi-diagrammatic sectional elevational view showing the relative positions of theneedles and looperas they are shown in heavy black lines in Figures 18a and 18h;

, Figure 20 isa similar view showing the needles and looper in the light line positions illustrated in Figures 18a and 18h; y v

Figure 21 is a similar viewshowing the positions of the needles and looper in the heavy dot and dash line positions shown inFigures 18a and 18h;

Figure 22 is a similar View showing the positions of. the needles and looper in the light dot and dash line positions shown in Figures 18a and 18h;

Figures 23 to 30 inclusive are semi-diagrammatic views illustrating the sewing operations;

Figure 31 is a View showing the completed stitch as it appears on one side of the seam ridge;

Figure 32 is a similar view showing the stitch as it appears on the reverse side of the seam ridge;

Figure 33 is a diagrammatic View illustrating the manner in which the finish and lining fabrics are presented to the sewing mechanism, and

Figure 34 is a diagrammatic View of the completed upholstery with the lining fabric stretched taut.

Referring now particularly to the drawings and more especially to Figures 33 and 34, the generall problem involved herein will be explained. In these figures the reference character F indicates the nish fabric or velour and the reference character L indicates the lining fabric or base material. In accordance with this invention the iinish and lining fabrics are united to provide a plurality of plaits or tubes with the stitching extending from outside the lining fabric into the interior of the tubes where the ,stitching is completed. Therefore, in accordance with this invention the finish fabric is gathered to provide a plurality of spaced seam ridges S and the lining fabric is arranged in superposed relation over the finish fabric with portions L thereof adjacent to and parallel with the seam ridges S at one side thereof. The lining fabric is spaced from the seam ridges at the other side thereof to provide for the completion of the stitch within the tube T. The finish and lining fabrics are united by transverse stitching Y extending from the outside through the portions L of the lining fabric L and through the seam ridges S of the finish fabric F, the needles extending into the space X where they cooperate with the loopers to complete the stitches. When the upholstery is subsequently applied to the seat the lining fabric L is stretched taut as shown in Figure 34, but inasmuch as no seam ridge has been gathered inthe lining fabric no strain is imparted to the stitching Y. Moreover, the stitching is substantially invisiblel upon the face of the completed upholstery. In this respect the finished upholstery is substantially the same as that constructed by the heretofore known manual methods of manufacture. f

In Figure 1 of the drawings the drive mecha,- nism will be explained. In this gurefthere is illustrated a motor 10 which drives a belt '11 which passes around a pulley 12 mounted on a shaft 13. The pulley 12 may be coupled to the shaft 13 by a clutch mechanism 14 actuated by a handle 15. The shaft 13 extends into a reduction gearing housing 16 and extending from this housing and driven ata reduced speed is a main shaft 17. A chain 18 `passes around a sprocket on the main shaft 17, thence around an idler 19 and around a sprocket on the shaft 20 which drives the cloth forming mechanism. From here the chain passes around a sprocket on the foundation forming mechanism shaft 21. From here the chain passes around a sprocket on the cotton bat feeding mechanism shaft 22 and thence around a sprocket on shaft 23 which drives the front roll and then back around the sprocket on the main shaft 17. lA chain 24 is driven from the shaft 13 and drives the sewing mechanism drive shaft 33 through gearing contained in the housing 26 and yet to be referred to more in detail. The gearing contained in the housing 26 is connected by means of a rod 27 to the looper operating shaft 28.

In Figure 10 the gearing for actuating the sewing mechanism and contained in the housing 26 is shown in detail and somewhat enlarged. The chain 24 passes around a sprocket wheel 29 mounted on a shaft 30 journaled in suitable bearings in the housing 26, this shaft being provided with a miter gear 31 meshing with a companion miter gear 32 on a drive shaft 33, the latter also being mounted in suitable bearings in the housing 26. Keyed to shaft 33 is an eccentric 34 with which the end of the rod 27 which actuates the looper shaft, is connected. Thus the looper shaft is oscillated in timed relation with the sewing mechanism for purposes which will appear more fully hereinafter.

Extending transversely of the machine are a pair of spaced parallel companion

sewing head shafts

35 and 36 each of which drives one of the companion sewing heads of each sewing mechanism which' as will be obvious comprises a pair of sewing heads. The

companion shafts

35 and 36 are driven through crank mechanisms which provide for differential or variable speed of each shaft. That is, the shaft is rotated during a portion of each rotation at a relatively rapid rate and during the remainder of each rotation at a relatively slow rate.

For this purpose the shaft 33 has keyed thereto a pinion 37 which meshes with a pinion 38 keyed to stub shaft 39 mounted on a suitable stationary part of the machine. Thus, these

shafts

33 and 39 rotate in unison. The end of shaft 33 has keyed thereto a crank 40 provided with an axial or longitudinal slot 41 and shaft 39 has keyed thereto a crank 42 provided with a similar axial or longitudinal slot 43.v The

shafts

35 and 36 are mounted eccentrically with respect to

shafts

33 and 39 respectively and shaft 35 is provided with a crank 44 provided with a pin or roller 45 which works in slot 41 of crank 40. Shaft 36 is provided with a crank 46 provided with a roller or pin 47 which works in slot 43 in crank 42.

With this mechanism each of the

shafts

35 and 36 is driven through a pair of eccentrically arrangedcranks, slidably interconnected. Therefore, when, for instance, shaft 33 is rotated crank 40 is consequently rotated and during its rotative movement it imparts a rotative movement to the corresponding sewing head shaft 35 through the slidable connection 41-45. However, owing to the eccentric relation of

shafts

33 and 35, shaft 35 is rotated at a Variable speed, its rotation being relatively rapid when the roller 45 is in the outer end of slot 41 and relatively slower when this roller is in the other end of slot 41, or in other words closer or adjacent the axis of rotation of shaft 33. The same or corresponding rotative movement is imparted to shaft 36 but owing to the reversal of the relation of the parts the shaft 36 is rotated rapidly while shaft 35 is being rotated slowly and vice versa.

By reference to Figure 2 it will be noted that there is fragmentarily illustrated a main conveyor 50 which forms spaced parallel seam ridges in the finish fabric and presents the same to the sewing mechanism. The structure of this main conveyor is illustrated more in detail in copending application Serial No. 462,620. The reference characters 5l and 52 indicate cooperating lining or foundation forming members which form the portions L in the lining'fabric and present this lining fabric in superposed relation with the finish fabric to the sewing mechanism. The construction and operation of this foundation forming mechanism is illustrated and described in copending application, Serial No. 590,275. As Will be observed in Figure 2, the

sewing head shafts

35 and 36 extend transversely of the machine and drive the sewing heads 53 arranged in pairs and mounted on the shafts inspaced longitudinal relation transversely. of the machine. The constructionand operation of each sewing head, which will be referred to more in detail hereinafter', is substantially the same as the sewing heads illustrated and described in copending application, Serial No. 400,317. In vthe former case each sewing mechanism comprises a pair of coopera ing sewing heads and in the latter case each sewing mechanism comprises a single sewing head and a cooperating looper. In the present construction each sewing mechanism comprises a, pair of sewing heads arranged so that the needles thereof work in vertical planes which intersect one another atan angle and a double looper reciprocating on a horizontal path in a Vertical plane which is intersected by the vertical plane in whicheach of the needles works.

The reference character 54 indicates a transverse frame member to which a plurality of bracket members 55, one for each looper mechanism, are mounted for adjustment transversely of the machine. For this purpose each bracket member may be provided with a bolt 56 having a T-shaped head which Works in aT-shaped slot formed in the frame member 54. These brackets support the looper shaft 28 previously referred to and for each looper there is keyed to this shaft 28 a link or arm 58 which is detachably connected by means 59 to a reciprocating head 60 which actuates a flexible looper actuating member or shaft 61. This head 60 reciprocates in a housing 62 carried by the bracket 55 and the flexible shaft 6l extends through a looper housing section 63 detachably mounted and a companion looper housing section 64 fixed to a member 65 which is adjustably cormected as at 66-for transverse adjustment to the frame member 54. The members 65 is provided with'bifurcations constituting forming shoes or members 67 which cooperate with a sewing plate 68 to hold the iinish material F in a position to present the seam ridges to the sewing mechanism, see particularly Figure 6. f

When the detachable connection 59 between the arm 58 and the head 60 is disengaged, the head 60 together with the flexible looper shaft 61, the looper 69 and the spaced guides 70 may be withdrawn longitudinally from within the

housing sections

63 and 64. Thus the looper may be repaired or replaced with facility.

As will be most apparent fromFigure 6, the looper housing section 64 in which the looper 69 reciprocates is mounted upon the shoe member 67 and extends within the tube or plait T formed by the finish and lining fabrics F and L.f The space X previously referred to is providedv by means of a tapered guard 71 fixed to one side of the looper housing 64.

By reference to Figures 14 to 17 inclusive the structure of the'looper 69 will be more apparent. It will be noted that the looper is shaped to provide a pair of opposed looperpoints 72 each of which is provided with a hook portipn 73. The looper is of such a cross-section at the opposite ends thereof as to iit within thelooper housing section 64 for reciprocation therein, the looper being reciprocated as will be obvious, by means of the flexible shaft 61 which is connected thereto at oneend thereof` vas shown most clearly in Figures 114.1and 15. i. `By" reference to Figures 4,6, 7, 8 and 9, theconstruction and arrangement of the'parts of the pair of sewing heads of each sewing mechanism will be more apparent. inasmuch as the construction of the sewing heads has been fully described in several of the aforesaid copending applications, the construction thereof will be but briefly touched upon herein.

For each of the sewing heads 53 mounted on each of the

shafts

35 and 36, these shafts are provided With, respectively, driving pinions 74. yEach pinion 74 Yis keyed toits respective shaft so as to rotate therewith but is capable of longitudinal movement thereon. Each pair of sewing heads 53 is adjustably mounted and supported by a'transverse frame member 75 by means of brackets 76 adjustably connected thereto by means 77. The pair of sewing heads 53 of each sewing mechanism are arranged at an angle to one another so `that the needles 78 thereof work in vertical planes which intersect one another at a substantially acute angle. Means is provided for imparting to each needle a thrusting and retracting movement and a rocking movement so that the needle will be thrust throughthe seam ridge and rocked to spread the loop carried thereby `and withdrawn, the latter ,being in itsretracting movement.

By particular reference to Figures 7, 8 and 9 it 5 will be noted that each of the sewing heads is driven" by one of the aforesaid pinions 74 which meshes with an idler pinion 79 on a stub shaft 80 j ournaled in the frame 81 of the sewing head. This pinion meshes with a pinion 82 on a stub shaft 83 also mounted on this frame 81. The pinion 82 is keyed to the shaft 83 and this shaft carries on one of its ends an eccentric crank disk 84 provided with a crank pin` 85. The needle arm 86 is pivotally mounted as at 90 on a sector shaped slide 88 and the needle arm 86 is rocked about its pivot 90 by means of a needle arm actuating link or crank 89 pivotally connected to the crank pin 85 and pivotally connected to the needle arm 86 as at 90. Thus upon rotation of the eccentric crank disk 84 the needle arm 86 is rocked about its pivot 87 by means of the crank arm 89. This imparts a thrusting and retracting movement to the needle.

The needle is rocked during its thrustingand retracting movementby shifting its pivot 90, this pivot being shifted in an arcuate path, the center of which arc is substantially the point C which point is in the arcuate path of needle 78 and in the central Vertical plane of the seam ridge. This shifting of the pivot 87 is accomplished by means of a link 91 which is pivotally connected to the slide 88 through the needle arm pivot 87, this link having a portion 92 which embraces the eccentric periphery of the crank disk 84. Thus upon rotation of the' crank disk 84, the link 91 is substantiallylongitudinally reciprocated and imparts an oscillatory shifting movement to the slide 88. This slide 88 is mounted in a guide 93.

By reference to Figure 5 it Will be noted that each of the sewing heads 53 is rockably adjustable about its

drive shaft

35 or 36 respectively independently of each other. For instance, the sewing head to the right as viewed in Figure 5 is provided with a pair of upstanding lugs 49 which embrace an adjusting screw 95 which in turn is ypivotallyv connected as at 96 to the bracket 76.

screw at its' free end and-engages the lug 94 at the outside thereof. Thus this unit. may be adjustably rocked about its shaft 35 as will be obvious. The left hand sewing head as viewed in Figure 5 has means for permitting adjustable rocking movement if desired. To this end the bracket 76 is provided with a bifurcated lug 99 through which rod passes, this rod being pivotally connected as at 101 to an extension 102 formed on the frame of the sewing head 53. The rod 100 carries a head 103 against which one end of a spring 104 engages, the other end engaging an internal shoulder on the sleeve 105. This sleeve has the end 106 thereof shaped to engage a corresponding surface on the lug 99. This construction will permit a rocking movement of the head 53 about its shaft 36 in one direction. In the other direction this is accomplished by a setscrew 107.

From Figure 6 it will be apparent that the seam ridge S which is first formed in the finish fabric F by means of the main conveyor 50 is presented over the sewing plate 68 and by reason of the cooperation of the shoes 67 the seam ridge is maintained as the material progresses toward the sewing mechanism so as to properly present each seam ridge to the sewing mechanism. As was previously pointed out the lining fabric L arranged parallel to the seam ridges S at one side thereof is formed and presented by the mechanism 51-52 previously briefly referred to. However. as the fabrics are presented to the sewing mechanism after leaving the foundation or forming means 51-52, means must be provided for maintaining this relationship of the lining material and tor this purpose I provide a guide plate member 108, see Figures 3, 4 and 6, this member having an upstanding nange portion 109 which holds the lining material against and parallel with the seam ridge S at one side thereof and with a base or foot portion 110 which guides the adjacent portion of the lining material. This guide plate member 108, as shown in Figure 4, may be conveniently mounted as at lll to the support 112. v

In operation the needles 78 have each imparted thereto a thrusting and retracting movement, one of the needles partaking of its thrusting movement while the other needle partakes of its retracting movement. The looper 69 reciprocates in a horizontal path in a vertical plane across the path of the n eedles in timed relation thereto, the purpose of the looper being, as will appear more fully hereinafter, to hold the loop formed by each needle until the other needlecompletes its thrusting movement to take the loop. It will be understood that each needle first partakes of a thrusting movement and rocks to open its loop whereupon this loop is caught up by one ofthe looper points 72 and positioned for engagement by the other needle at the end of its thrusting movement, the loop formed by this second needle being held by the other looper point 72 for en-v gagement by the first mentioned needle on its next thrusting movement.

In Figures 18a and 18h each needle is shown in the position it assumes at the end of its retracting movement, at the end of its forward or thrusting movement, and at two intermediate positions, the cycle of needle movement being divided into four increments, and by comparison of Figures 18a and 18h, the relative positions of the pair of needles can be determined at each of these points in the cycle, particularly when considered in connection with Figures 19 to 22,

inse-,919

each of which figures indicates in plan View the relative positions of the two needles and the looper. v

. As probably most clearly illustrated in Figures 18a and 18h the needle 78 is rocked to cause its point to describe a loop, this rocking movement occurring particularly during the end of the thrusting movement and the beginning of the retracting movement of the needle so that each needle may be thrust forward on an arc, the medial line of which extends over the horizontal plane of the adjacent looper point 72 and then the needle isA rocked to dip the point thereof downwardly so that this point is arranged in a horizontal plane below the longitudinal horizontal plane of the looperpoint. This spreads the loop carried by the needle and permits the looper point '72 to pass through the loop so as to hold this loop for engagement by the other needle. It will be understood that the eccentric crank drive connection for each sewing head shaft 35 is so arranged .that the needle '78 is thrust into and through the seam ridge and withdrawn therefrom relatively rapidly, the speed of the needle varying and being somewhat slower during the remainder of the movement of the needle so that the increment of time during which the needle is engaged with the fabrics is reduced.

By comparison of Figures 19- to 23 inclusive it will be noted that needle 78a is at the end of its thrusting position and at this point is being rocked downwardly to spread the loop carried thereby so that the looper point 72d may pass over the needle and engage the loop formed thereby. The needle '78h is commencing its thrusting movement and will take the loop from the looper '72a during the end of the thrusting movement of the needle '781). This position of the needles is shown in heavy black lines in Figures 18a and 18h.

In Figure 20 the needle '78a is practically at the end of its retracting stroke and the loop is shown as carried by the looper point 72a and is being engaged by the needle 78h which is near the end yof its thrusting stroke. The looper is now moving in an opposite direction and assists in freeing the loop and depositing it on the needle 78h. This position of the needles is shown in solid light lines in Figures 18a and 18h.

In Figure 21 the needle '78h has taken the loop from olf the looper' point '72a and the needle 78h is about at the end of its thrusting movement and is being rocked downwardly to spread the loop carried thereby forengagement by the looper point 72b. The needle '78a is at about the end of its retracting stroke and has again started its thrusting movement. This position of the needles is shown in heavy dot and dash lines in Figures 18a and 18h.

In Figure 22 the looper point 72b is shown as holding the loop which it tool; from the needle 78h and the needle 78a is shown on its thrusting movement taking the loop from off the looper point 72b, the looper moving back again to assist in transferring 'this loop from the looper point 72h to the needle'78a. The needle 78h is near the end of its retracting stroke. This position of the needles is shown in light dot and dash lines in Figures 18a and 18h.

The sewing operation will probably be more apparent by a comparison of Figures 23 to 30 inclusive. In these gures the thread carried by the needle 78a is shown in heavy lines and the thread carried'by' the needle 78h s'shown in light lines.

rloop which has just panaderov The direction of movement of the needles and locper is indicated by arrows in each ligure.l

In Figure 23 the'needle '78a is at the end of its thrusting stroke andthe beginning of its retracting stroke-and has been rocked to lower the pointbelow the horizontal plane of the path of movement of the looper point 72a which is partaking of its thrusting movement or in other words, its movement to the leitl- In Figure 24 the looper point 72d has taken the loop from the needle Vr78a which is on its retracting's'trolre and the looper point '72e is partaking of its retracting movement as the needle 78bis taking the loop from oii the looper point 72a. In Figure 25 the needle '7819 has already completely takenthe loop from the loopery vto partake of its reeen rocked'to spread 72b may holdthe point '72a and is beginning tracting movement and has its loop so that the looper point loop of needle 78h;

In Figure 26 the loop of needle '78h is'shown as transferred to the looperfpoint 72b and the needle 78d is at the end of its thrusting stroke and is taking the loop from the loopen-'point 1.721);

the looper point 72bat this stage being-retracted to assist in transferringthe loop fromithe point 72o'to`the needle 78d.. n

In Figure 27 the loop has been completely transferred from the looper point '72b to the needle '78a and this needle has partaken of a vrocking movement to spread its loop so that the looper. point 72d may hold the same for engagement bythe needle 78h. The needle 78h is shownas'taking this loop from the looper point 72d in Figure 28 and as the looper point 72a retracts from the loop 'to assist in .transferring the same to the needle 78h, the needle 78h continues its thrusting movement and simultaneously partakesof a rocking movement, this position of the parts vbeing illustrated iii-Figure 29. x

In this position shown in Figure29, the looper point 72b is again ready to take and .hold the been spread by the rocking movement of the needle 78h and in Figure 30 the needle 'iSd is shown as having already taken the loop off the lcoper point 72b and as having partalren of its rocking movementV to spread itsloop which will be taken and held by the looper point 72d for engagement by the needle 78h during the end of its thrusting movement.

The resulting stitch is a double chain stitch shown in Figure 31, the reverse side of the line of stitching being illustrated in Figure 32.

The herein described sewing mechanism provides means for stitching and forming tubular upholstery where the stitches extend from the outside of the tubes to the interior thereof where they are completed, the stitches passing through but a single thickness of the lining or backing material and through a seam ridge in the iinish or top fabric. Thus the backing material may be stretched taut without imparting any strain to the stitches, this being customary when the upholstery is applied to the seat or back. The invention contemplates a structure wherein the lcoper is not threaded but merely reciprocates in a path which intersects the path of travel of the needles, the looper acting to hold the loops formed by each needle for subsequent engagement by the other needle. With such an arrangement the needles may be operated each at a variable speed so that the period during which the needle is being thrusted and retracted through the fabrics may be lessened or shortened. This permits of a rapid, smooth and continuous sewing operation at a high speed which is conducive of'eiiiciency in commercial production. l

' Obvious modifications, changes and re-arrange-y ments of the parts may suggest themselves to thoseiskilled' in this art and to this-end reservation is made to make such changes as may come within the purviewof the accompanying claims.

Whatl claim as my invention is:

l. Sewing mechanism including a pair of needles working in longitudinal vertical planes which intersect one another, anda looper working 4in a longitudinalvertical plane which intersects the workingplanes 'ofthe needles at theV point of intersection thereof.

2. Sewing mechanism comprising a pair of needles working in longitudinal vertical planes at an angle to ,one another, each needle having .a thrusting and retracting movement which intersects thev working plane'of the other needle and a reciprocating looper working in a vertical longitudinal plane which intersects the working planes of the needles at the point of intersection of lthe needle paths.

3. Sewing mechanism comprising a pair of needles rworking in longitudinal vertical planes at an angle to onel another, each needle having a .thrusting and retracting movement and a rock-p ing movement, and a reciprocating looper working ina vertical longitudinalplane which intersects the working planes of the needles.

Ll. Sewing mechanism comprisinga pair of needles working in vertical longitudinal planes at an angle to one another, each needle having a thrusting and Vretracting movement through a seam, and a rocking movement about tiallyin the vertical longitudinal plane of the seam, and a .reciprocating looper working in a vertical longitudinal plane which intersects the working planes of the needles.

5. Sewing mechanism comprising a pair of needles working in vertical longitudinal planes at an angle to one another, each needle having a thrusting and retracting movement and a rocking movement prior to the thrusting movement of the other needle, and a reciprocating looperworking in a vertical longitudinal plane which intersects the working planes of the K needles.

6. Sewing mechanism comprising a pair of needles working in paths which angularly intersect one another, said needles respectively partaking simultaneously of thrusting and retracting movements, each needle having a rocking movement at the end of its thrusting movement, and a looper reciprocating in a horizontal path which intersects the paths oi movement of said needles.

'7. Sewing mechanism comprising a pair of needles working in paths which angularly intersect one another, said needles respectively partaking simultaneously of thrusting and retracting movements, each needle having a rockingL movement at the end of its thrusting movement, and a looper reciprocating in a horizontal path which intersects the paths of movement of said needles in a horizontal longitudinal plane between the upper and lower limits of the rocking movement of the needles.

8. Sewing mechanism including a pair of needles each reciprocated in an arcuate path about a center which is shifted on an arc struck from a point in the arcuate path of the needle and a reciprocating looper working in a longitudinal horizontal plane which substantially intersects the normal longitudinal medial line of the arcuatepath of the needles.

9. Sewing mechanism comprising a pair of neea point substandles, means for reciprocating each needle to cause the same to axially pass through the same longitudinal horizontal plane in the seam, means for rocking the needles about the point of intersection of said plane with the seam to shift the point thereof from a point above said plane to a point below said plane, and a looper reciprocatingin a horizontal plane substantially coincident with the plane of the seam through which said needles pass.

10. Sewing mechanism comprising a pair of needles working in vertical longitudinal planes at an angle to one another, each needle having a variable speed thrusting and retracting movement and a rocking movement, and a looper working in a path which intersects the working paths of the needles at the point of intersection of the needle paths.

11. Sewing mechanism comprising a pair of needles working in vertical longitudinal planes which intersect one another, each needle having a thrusting and retracting movement, a looper reciprocating in a horizontal path which intersects the working paths of the needles, each needle having a rocking movement to lower its point end substantially prior to the commencement of its retracting movement past the point of intersection of the looper.

12. The combination with means for feeding plies of finish and lining fabrics and forming seam ridges in one fabric and arranging the other fabric parallel to the seam ridges at one side thereof, of means for uniting the fabrics comprising a pair of needles having thrusting and retracting movements through the parallel and seam ridge portions of the fabrics into the space therebetween, and a double looper reciprocating within said space cooperating with said needles to complete the stitches Within the space between said fabrics.

13. The combination with means for feeding plies of finish and lining fabrics and forming seam ridges in one fabric and arranging the other fabric parallel to the seam ridges at one side thereof, of sewing mechanism for uniting the fabrics including a pair of needles working in angularly intersecting paths, means for imparting a thrusting and retracting movement to each needle to thrust the same through the parallel and seam ridge portions of the fabrics into the space therebetween, and a double pointed looper reciprocating in said space and cooperating with said needles to complete the stitches within the space between said fabrics.

14. The combination with means for feeding plies of finish and lining fabrics and forming seam ridges in one fabric and arranging the other fabric parallel to the seam ridges at one side thereof, of sewing mechanism for uniting the fabrics including a pair of needles working in angularly intersecting paths, means for imparting a thrusting and retracting movement to each needle to thrust the same through the parallel and seam ridge portions of the fabrics into the space therebetween, anda double pointed looper reciprocating within said space and cooperating with said needles to hold the loop of one needle for engagement by the other needle whereby to complete said stitches within the space between said fabrics.

15. The combination with means for gathering finish fabricl to form spaced seam ridges and arranging aV lining fabric with portions thereof parallel to the seam ridges to form tubes therebetween, of sewing mechanism including a pair of needles, means for thrusting and retracting said needles through the parallel and seam ridge portions of said fabrics in paths which intersect one another Within said tubes, and a double pointed looper reciprocating within said tube for alternately holding the loop of each needle for engagement by the other needle.

16. The combination with means for gathering a finish fabric to form spaced seam ridges and arranging a lining fabric with portions thereof parallel to the seam ridges to form tubes therebetween, of sewing mechanism including a pair of needles, means for thrusting and retracting said needles through the parallel and seam ridge portions of said fabrics in paths which intersect one another within said tubes, means for actuating said needles each at a variable speed, and a double pointed looper reciprocating within said tube for alternately holding the loop of each needle for engagement by the other needle.

BYRON F. EVERI'I'T.