US1243745A - Sewing-machine. - Google Patents

Description

J. G. LEWIS.

SEWING MACHINE.

APPLICATION FILED OCT. 8. 1915.

- Patented Oct. 23,1917.

5 SHEETS-SHEET M Mm .5 m Z a w J. G. LEWIS.

SEWING MACHINE.

a APPLICATION FILED ocTLa. I915.

Patented Oct. 23, 1917.

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SEWING MACHINE. APPLICATION man 0cT .'8. 19:5.

: Patented Oct. 23,1917;

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I G. LEWIS. SEWING MACHINE.

APPLICATION FILED 001.8. ms. 1,2%3,;7%, Patented,0ct. 23,1917. v 5 SHEETS-SHEET 5.

JOHN G. LEWIS, or s'r. rlouis, mrssoonr.

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Specification of Letters Patent.

Patented Oct. 23, rear.

' Original application filed December 6, 191's, Serial No. 805,160. niviaeaana this application and October a,

1915. .Serial No. 54,777.

To all whom it may concern:

Be it known that I, JOHN G. LEWIS, a citizen of the United States, residing at St. Louis, in the city of St. Louis and State of Missouri, have invented certain new and useful Improvements in Sewing-Machines,

of which the following is a specification.

My invention relates to improvements in sewing machines, and in some of its features more. particularly to blind stitch sewing machines, especially of the type illustrated in' copendin ap lications Serial No. 599,071, filed fiecem er 24th, 1910, patented February 22, 1916 No. 1,172,812 and Serial No. 805,160, filed December 6th, 1913, the latter application, of whichthis is a division, being in turn a division of application Serial No. 599,071.

Among the general objects of. my invention I seek to provide a machine readily adapted, in the character of its work-handling mechanism, to widely different sorts of work; capable of high speed and fastop- Fig. 9 is a sectional detail on line 9-9 of Fig.

Fig. 10 -is an enlarged vertical section through-the rear post of the machine;

Fig. 11 is a cross section through said post;

length-adjusting eccentric;

Fig. 13 is a section on line 13-13 of Fig. 12;

Fig.14 is a sectional detail of a modified plunger and clamp;

Fig. 15 is a sectional detail showing such plunger and a cooperating presser. foot.

' The machine organizatlon in general, as herein sh'own, preferably comprises a frame having anupper arm 21, carrying the head 22 for the stitching mechanism. In said .head are arranged the "moving parts of the stitch-forming mechanism, working above the presser foot 23, which may be substantially stationary. The upper arm 21 projects from the standard or post 25 supported eration; suitable for handling materials of by a base casting 26 constituting a lower arm widely varying thickness and abruptly changing numbers of plies;-and generally of simple and eificient construction and organiz ation.

The many novel features of my invention productive of improved and novel mechanical organization, and resulting in the performance of novel functions may best be ascertained from the appended claims in con junction with the following specification and accompanying drawings.

In the drawings Figure 1 is a front elevation of a fiatbed machine; 2'. a, a machine for handling flat work, and accordingly having a wide work-support v Fig. 2 is an end elevation with parts in section showing the work handling mechanism and associated presser foot; 1

Fig. 3 is a sectional view on line 33 of Fig. 7 showing said mechanism from the opposite side;

Fig. 4 is a vertical section on line 14 of Fig. 2;

Figl 5 is a plan view of the parts shown in Fig. 2;

Fig. 6 Fig. 7 Fig. 7 is a vertical section through the lower arm of. the machine;

Fig. 8 is a detail of the spring support;

is a sectional detail on line of "of the machine, and afiording support to the working parts of the work-handling mechanism generally indicated at 27, (Fig. 1). In the particular construction shown the base 26 is adapted to fit an opening .cut therefor in a work'table 28 and above the frame there is provided a fiat work Fig. 12 is an enlarged detail of the feed support 29 pivoted as at 30 in ears pro-1 vided on the frame 26, and bearing near its free end on an adjustable stop 30. work support 29 is provided with a suitable opening 31 through which the feed and plunger mechanism may work, such opening preferably flanked by slide plates 32 removable to give ready access to the subjacent parts.

Stitch forming mechanism, such as that generally illustrated in Fig. 1, is fully described in my copending applications previously identified, of which this is a division, and for present purposes it sufiices to say said stitch forming mechanism 22 comprises a reciprocating, curved, side pointed needle 22 working above the presser foot and cooperating with a rotary hook 22 and suitable thread controlling parts, for the formation of blind lock stitches, the needle entering and emerging from the same side of the work which is presented to the action of the presser foot 23. p

The

- Q I Lasagna The work handling devices comprise, in general, a plunger or bender reciprocable to present the stitch-receivin portion of the goods through the presser oot opening 23;

-clamping means to cooperate with .the

presser foot to clamp the goods thereagainst at the time the plunger elevates the node of goods through the presser foot opening; and a 4-way feed structure. The active parts of these instrumentalities receive motion from these shafts 41, 42, and 43, extending longitudinally through the lower arm of the machine and at their outer ends find bearing in a head block 40 which is preferably in the form of a major segment of a cylinder, attached to the base by screws 40. The arrangement shown is advantageous in that it brings all of the longitudinal shafts of the base into an area of small compass so that, if

desired, said shafts and mechanisms may be readily mounted on a base cylinder of relatively small size in lieu of the flat bed, the block 40 conforming to the end of such a cylinder. In this way the machine may be set up for work on sleeves, trousers bottoms and the like, with only a change of the base] casting and work support.

The plunger or bender generally indicated at is a vertically reciprocating member operated by the rock-shaft 41. vided with an appropriately shaped nose or tip to cooperate with the back of the oods in elevating a node of goods throug the presser foot opening 23. In the particular construction shown, 46 indicates a barrel of the plunger mounted to slide vertically in a guide opening in head block 40, the bottom of said barrel being reduced to form a throat 47 secured in an offset lug 48 projecting from a slide plate 49 which works in aslide way 50 in the 'inner face of the head block 40, said slide way'opening to a recess 51 across the bottom of the block to accommodate the movement of the lug 48. To impart vertical movement to the slide 49 the plunger-operating rock-shaft 41 has a crank 53 having a pivot connection with link 54, the opposite extremity of which is pivotally connected to the slide 49. In order that the limit of vertical movement of the slide 49 may be varied and the limit of movement of the plunger correspondingly changed, the.

connection between the slide 49 and the upper extremity of link 54 is made adjustable. To this end the upper extremity of link 54 is formed into a clamp 55 engaging a rotarily adjustable sleeve 56 eccentrically aper tured and surrounding a pin 57 projecting from the slide 49. Obviously by rotating the eccentric 56 by means of its knurled head 58, and clamping it in desired position, efiective variation in the limits of throw of the plunger may be attained at will.

The tip or nose of the plunger is preferably yielding relative to the body or posi It is pro-- tively-moved part thereof, to constitute a yielding back guide. To this end the head 60 is mounted on a stem 61 extending into the central bore of the barrel 46 and reduced at its lower end, as at 62, to pass through the throat 47 and receive the exterior stop nuts 63. The reduced portion 62 of the stem is surrounded by a coiled spring 64 yield--' ingly maintaining the stem at its upper limit I of movement relative to the barrel. Rotation of the stem relative to the barrel is prevented by slot and key engagement therebetween,-as shown by key 65 and slots 66. I The yieldability of the plunger thus provided is particularly advantageous in relieving the machine from strain under extraordinary increases in the thickness of work.

Preferably the'power connections of the plunger mechanism, or its rock shaft 41, are

such that in the rocking movements of the I shaft, occurring with each revolution of the main shaft, (through connections hereafter described) one crank arm in the train swings to, or, moves desirablv past dead center slightly so that the operation of the plunger is to rise from lowest to highest position and then to dwell, or to dip or recede slightly, before commencing its return movement to lowest position; in the latter instance securing what I will term a secondary retraction of the plunger tip, of considerable time duration, but slight linear extent, occurring while the plunger is adjacent its upper limit of movement, in its position of functional I cooperation with the needle.

lln operative association with the plunger I provide a clamping mechanism for 'cotip eration with the presser foot to clamp the goods against the presser foot so that the plunger may draw the clamped goodstaut before the needle penetrates the work. It is preferable that these two cotiperating parts plunger andclampshall be inter-related so that one is carried by the other yieldably through the inter-position of a spring beno tween the parts, in order that wear in the operating parts may not change their special relationship or affect their coiiperative functioning, and to insure theirproper coaction with goods of widely-varying thickness. 7

In the particular construction shown I prefer that the plunger or bender be the positively driven part, sliding in the frame to define the line of movement of the two cooperating mechanismsplunger and ciprocating movement. 4 The precise config- 1130 I variations as may reciprocation uration of the clamping means will, of course, be varied'to correspond with such be made in the precise form of plunger head, but in the specificconstruction shown, the clamp 70 is a cup shaped member surrounding, or substantially surrounding, the head of the plunger and yieldably mounted upon the plunger for erewith. 71 indicates the rim of the clamp, the upper edge of which ing and spaced apart somewhat from the plunger head to operate against the under side of the presser foot. 72 indicates the annular base of the clamp member surrounding the stem 61 of the plunger below its head. A spring 73 interposed between the plunger barrel 46 and the clamp base, normally maintains the clamp with its stop pins 74 abutting against a stop pin 75 of the plunger and guided in the side slots 66 of the plunger, these parts having sufficient looseness of fit so that theclamp is capable of yielding movement to tilt universally to some extent relative to the plunger head, the clamp obviously being slidable longitudinally upon the plunger stem. If desired pins 74 may be omitted and the clamp left free torotate.

The plunger head may be suitably shaped according to the character of the Work to be done, a rounded plunger being one commonly employed in certain classes of work,

i and when such construction is used the presser foot opening 23 is usually appropriately shaped to give a clear orifice slightly greater than the size of the plunger tip. In some classes of work, however, as in felling edges, the machine may be given a capacity for handling without readjustment, materials of widelv varying thickness, limiting the stitch to a given depth, by appropriate relation of the presser foot andcannot strike deeper into the goods than the setting of these parts of the machine will permit, so insuring that the stitching shall be confined to the desired plies or depth of the goods. When the goods imposed on the plunger are not thick enough to reach the front guide or stop, the natural limit of movement of the plunger, acting under such circumstances as a back guide, prevent the goods from being raised so far as to cause the stitching to show-through on the fair side of the' goods', and where no front guide or stop is used, the plunger raises the fair side of the goods to substantially uniform position under widely varying thicknesses of work. It will be noted hereinafter that after the plunger rises to its highest point, it may dip or bob slightly, after the needle has started to penetrate the goods, so relieving from any grinding or abrading action that portion of the goods lying between the moving needle and the plunger, and serving other useful functions incident to successful and high speed work.

The feeding of the goods is accomplished by a feed dog 80, operating against the under surface of the presser foot and driven laterally of the shafts, or fore-and-aft as to its direction of feed, from the lateral feed shaft 42, and vertically from the vertical feed shaft 43. The feed dog 80 is thus driven entirely by axially fixed, solid shafts, dispensing with universal joints or other means for attaining flexibility, but the mounting and connections of the dog are such that it has a desirable and sufficient capacity for adaptive movements. Thus the dog is preferably swiveled on a horizontal axis and is capable of rocking motion to compensate for variations in thickness of material interposed between the presser foot and different foreand-aft areas of the dog, thereby to enable difierent points of the toothed surface of the dog appropriately to coact with the worlc Also the dog is preferably so mounted upon a carrier, spring pressed to normal position, that at any plane of its cyclic operation and regardless of Whether or not the drive shafts are in motion, the dog may be depressed to permit the insertion, removal or shiftin of the Work. To the latter end, I provi e in the connection of the feed dog to the lateral feed shaft 42 a 1 generally horizontal pivotal connection and 1n the connection of said dog to the vertical feed shaft 43 I provide agenerally horizontal connecting element associated with the vertically slidable spring pressed carrier so that the feed dog may make vertical excursions with the vertically moving carrier, without substantially disturbing its relation to the drive shafts or to those driving connections which impart movement from the drive shaftsto the feed dog; In the particular construction shown, the dog is provided with three feed points 81, two of which preferably flank the plunger and clamp mechanisms, while the third is beyond the plunger with reference to the direction of feed. To the forward extremity of the feed dog is connected, preferably pivotally. a wide link 82 arranged at a relatively small angle to the horizontal and at its remote extremity said link is pivoted to a crank 83 mounted on the shaft 42 to be moved fore and-aft by the rockin of said shaft. At a suitable point, prefera ly near its fore-andaft center, the feed dog has pivotal connection to the extremity of a generally-vertical link 84, and because of the pivotal connection of the feed dog to both of the links 82 and 84 its normal, substantially horizontal, presentation to the presser foot is maintained byva spring 85, connected between a pin 86, on the link 84, and a pendant tail 80' of-the feed dog. The lower extremity of the link 84 is pivoted to a horizontal arm of a bell crank lever 88, the vertical arm of which, upwardly extending, has connection by a substantlally-horizontal link. 89, with the crank lever 90 working fore-and-aft on the extremity of the vertical feed shaft 43. Obviously the appropriately timed rocking of the two shafts 42 and 43 will impart 4-way feed motion to the feed dog.

The pivot 88, on which the bell-crank lever 88 is mounted, is a part of a carrier or carriage 91, said carrier comprising a suitable guide post 92 lying in a suitable opening in the head block 40 and a head 93 to which said part is secured by a screw 94 extending through the pivot portion 88. The carriage head 93 works in a recess 95' in the head block 40, and upon the head 93 1 preferably mount a bumper spring 96 to ease the action of the carriage under high speed. The carriage is normally spring pressed upwardly as by a strong leaf spring 98, the tip of which engages in a recess 99 in the carriage head 93. The base of the spring 98 passes over a fulcrum luglOO on the frame and near its extremity it is engaged by a block 101 adjustable to vary the tension of the spring, as by means of an adjusting screw 102, extending through the block and spring and through a fixed lug 103 of the frame.

The spring 98 holds the carriage 91 normally in raised position so that the 4-way movement of the feed may occur in proper vertical relation to the goods to be fed, and to the under side of the presser foot, but it will be observed that the carriage may be 1 depressed against the tension of its leaf spring, either incidentally to the functional operations of the feed or for the purpose of dropping the feed to permit the goods to be inserted, removed, or shifted. Obviously, when the carriage is depressed, carrying with it the pivot member 88' for the bell crank lever 88 of the feed system, the lowering of the bell crank lever draws down the link 84 and with it the feed point, the generally horizontal link 89 and the generally horizontal link 82 both swinging downward to accommodate the displacement of the feed point and bell crank lever. Neither of these links need be in precisely horizontal narrate-e position to accommodate this movement, but

- shown is such that the depression of the carriage and the feed dog maytake place re-' gardless of the position of the cranks 83 and 90 in the cyclic operation of the feed, and when the carriage is depressed the. feed dog will continue to efi'ect its 4-way movements. Any appropriate means may be provided for depressing the, carriage 91 at, will, the construction herein shown providing a rock ingframe 104 arranged to act on the spring 98, and a lmee lift for actuating said frame. Specifically 105 and 105' indicate end arms of the frame, both loosely pivoted on the plunger shaft 41, and connected by a frame bar 106, one of said arms, as 105, having an extension 106' to act on the spring 98 near its active end and the other arm having a lever extension 107 for operation by the knee lift mechanism 108 upon the table 28. A spring 109 normally holds the rocking frame retracted. The three rock shafts 41, 42, and 43 are driven and timed by three eccentrics 111, 112 and 113 respectively, mounted on the main shaft 10, above the post 25 through which the arms 121, 122 and 1 23, respectively, of the several eccentric straps, extend for connection with the cranks appurtenant to the rock shafts 41, 42 and 43. Eccentrics' 111 and 113 for the plunger shaft and the vertical feed shaft may be set or fixed eccentrics of any usual character. centric 112 for operating the horizontal feed shaft 42 is preferably adjustable as to its eccentricity in order that the length of fore-and-aft throw the feed dog may be varied to change the spacing between stitches. As a simple means to this adjustment, cam 112 is made in the form of an an nular ring with a large center opening carried by a plate 114 which has an ofiset end lug 115 guided in an edge recess 116 in a disk 117 fast on the shaft, said plate being additionally guided by a slot and pin connection with the disk, as shown at 118. An adjusting screw 119 taking through the lug 115 into the block 117, and springs 120 acting between the bottom of the recess 116 and the lug 115 serve to efiect and to hold the desired adjustment of the eccentric, changing the degree of its eccentricity but not its time with reference to the main shaft.

The arm 1211 moved by the eccentric 111 is connected to the mid portion of a lever 125 which is pivoted near its one end to a depending lug 126 of the end wall of the frame and which is connected at its other end by link 127 .with the crank arm 128 on the shaft 41, said shaft at its rear end being The ecjournaled in said lug 126. The other two shafts 42 and 43stop short of the end wall lug 126 so as not to interfere with the movement just described, said shafts being supported adjacent their rear end by a lug 129, depending from the frame in substantial alinement with the inner side of the post 25. The strap arm 122 of the adjustable eccentric for the feed is connected direot to the wrist pin of crank 130 carried by-horizontal feed shaft 42 and strap arm 123 for the remaining eccentric 113, has pivotal connection with the wrist pin of crank 131 mounted on vertical feed shaft 43.

It will be noted with respect, to the link.- age connection from eccentric 111 to rock shaft 41 that the throw imparted to the shaft 4:1 will be of considerable angular extent, and the relation between the two cranks 128 and 53 carried by said shaft 41 is prefer ably such, as heretofore described, that the crank 53 is thrown over dead center as crank 128 approaches its upper limit of throw. Among the'important features of the construction described, is the capability of the feed mechanism to be lowered at will, regardless of the position of either of the inflexible shafts 41 and 4:2 in their cyclic operation. This arrangement permits the operator to substitute manual control of the feeding of the goods for the automatic feed at any time when the exigencies of the work may so require. For instance, sharp turns in the goods, to change the direction of the lines of stitching, may be made, andespecially when the machine is being operated as in'tacking, padding collars or the like, the operator may sew forward and backward at will, allowing the forward feed to be effected by the automatic feed mechanism and (after depressing the feed) drawing the goods backward by hand.

During such a, manual feeding operation the clamp operates to clamp the goods during every penetration of the needle so obviating the possibility of damaging the needle and also insuring proper tensioning of the goods on each such stitch. Obviously the goods may be shifted or fed laterallywhile the feed dog is held out of commission and thus blind-stitch tacking may be done rapidly and facilely.

The action of the clamp insures proper tensioning of the goods against the thrust of the bender or plunger at all times; its

' yieldability in all directions gives it the quality of accommodating itself to varying thicknesses of work, be they in lateral or fore-and-aft direction with respect to the line of feed; and the inter-relation of the clamp and the plunger so that one is carried by the other and the carried element is spring supported with respect to the other,

gives them an automatic compensation totake up the eflect of wear, in their operating mechanism, and a certainty of proper coaction with the goods, which in practice is found to be highly advantageous.

While I have herein described insome detail a particular embodiment of my invention, which I have commercially used and found to be highly desirable in many ofits structural details, as well as in the general combination of elements, it, will be understood by those skilled in the art that many changes in the specific embodiment rier acting normally to elevate the carrier,

means to depress the carrier, a feed dog,

actuating shafts therefor, connections between said shafts and the feed dog to impart a 4-way cyclic movement to said dog from the operation of the shafts, said connections permitting said dog to move relative to the shafts with the carrier, and connections between the dog and carrier for moving the dog with the carrier, permitting the dog to receive its 4-Way movements from the shafts in any position of the carrier.

2. In a sewing machine, the combination of a base, a carrier slidable vertically in the base, a spring arranged normally to elevate said carrier, means to depress said carrier, a feed dog, a transverse feed shaft, a crank thereon, a horizontally-disposed link pivoted to the crank and to the feed dog; a vertical feed shaft, a crank thereon, a lever pivoted on the carrier, connections with the last said crank and the feed dog, said connections with the crank including a horizontally extending link, and said connections with the feed dog including a vertically-extending link whereby said feed dog may move with the carrier relative to said 7 shafts and receive its 4-way movement from feed shaft and lever including a horizontally disposed link, whereby depression of the carrier lowers the dog relative to the shafts without disturbing the shafts or their working connections with the dog.

4. In a sewing machine, the combination of a stationary presser-foot, a feed dog therebelow, two rock shafts having their axes fixed in relation the resser foot, avertically slidable earner, a spring normally holding said carrier, raised toward "the cranks with the vertically extending lever arm and with the feed dog, respectively,

5. In a blind'stitch sewing machine, the

combination of a base, a carrier vertically movable in the base, a spring between the base and carrier acting normally to elevate the carrier, means to depress the carrier, a feed dog, actuating shafts therefor, connections between" said shafts and feed dog to y neeavee impart a t-waycyclic movement to said dog from the operationof the shafts, said connections permitting'said dog to-move relative to the shafts with the carrier, and to tilt pivotally in any position of its relative 2a movement, spring means tending to hold the dog in one position within its tiltingrange, and connections" between the dog and carrier for moving thedog with the carrier,

permitting the dog to receive its 4-way 80 movements fromthe shafts in any position of the carrier.

In testimony whereof I hereunto set my hand in the presence of two subscribing Witnesses.

JOHN LEWIS.

' In the presence of STANLEY W. Coon, MARY l ALLEN.

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