US3791325A - Sewing machine - Google Patents

Abstract

A sewing machine with a pair of wheels for conveying material layers to be joined by stitching. The conveying wheels are arranged in the stitch-forming area with each wheel associated with a member for driving said wheel continuously with the same peripheric speed. To the needle block are associated members driving said block alternately along the conveying direction. One of said wheels is retractable to allow feeding of the material layers to be joined by stitching.

Description

United States Patent De Koninck 14 1 Feb. 12, 1974 SEWING MACHINE 2,470,502 5/1949 Vesconte et a]... 112/214 2,866,426 12/1958 Wrase 112/214 [76] Inventor: Alphose De Avenue, 3,216,386 11/1965 Bono 112/214 x Sleeckx 84, Schaerbeek, Belgium 22 Filed; May 9 1972 7 Primary EXaminerWerner H. Schroeder Attorney, Agent, or FirmOtto John Munz [21] Appl. No.: 251,643

' 7] ABSTRACT Foreign Application Priority Data A sewing machine with a pair of wheels for conveying June 7, 1971 Belgium 104320 material layers to be joined by stitching. The conveying wheels are arranged in the stitch-forming area with [52] US. Cl. 112/213, 1 12/214 each wheel associated with a member for driving said [51] Int. Cl. D05b 27/10, D05b 27/20 wheel continuously with the same peripheric speed, [58] Field of Search 112/213, 214 To the needle block are associated members driving said block alternately along the conveying direction. [56] References Cited One of said wheels is retractable to allow feeding of UMTED STATES PATENTS the material layers to be joined by stitching.

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sum 3 0F 3 PATENTED FEB] 21974 lfllllllf SEWING MACHINE This invention pertains to a sewing machine which comprises at least one needle and two superposed wheels for conveying the material layers to be stitched, said wheels engaging one another with the circumference thereof through said material layers.

A plurality of solutions have already been proposed to avoid during the sewing a wrinkling of the material layer conveyed to the needle block of the machine, due to said layer being driven less positively than the opposite layer brought to the hooks or the other stitchforming elements the drawback of a sliding between the various layers to be joined being particularly noticeable when finishing article edges with a ribbon of material with a low adhesion, for instance a silken ribbon.

One of the proposed solutions lies in adding to the usual mechanism with conveying claw and presser foot, a conveying roller driven intermittently, which is arranged on the presser foot side but with a staggering relative to the claw. Such an arrangement which is not usable for sewing narrow edgings, does not prevent the staggering of the upper layer relative to the lower layer as the upper layer driving is disturbed by two unaligned drives, and moreover the synchronizing of the drive by the claw and the rollers is impossible, which also adds to an improper working of the machine.

Another proposed solution lies in arranging behind the presser foot of a machine comprising in the usual way a presser foot and a conveying claw, a pair of conveying wheels which are driven intermittently when the claw feeds the article to be stitched. This arrangement has however the drawback on the one hand of excluding the stitching of curved articles and on the other hand, of causing irregularities in the work due to the jerks caused by the conveying wheel intermittent drive. In this case also a synchronizing of both drives is impossible another drawback results from the spacing between the claw and the conveying wheel pair which is w y bo m... f r 9 Starting 9UP? WEEK- A known solution of a different kind, applied to machines with presser foot and conveying claw, lies in imparting to the needle block in addition to the usual alternating movement in and out of the material layers to be stitched, an alternating movement along the conveying direction said movements the resultant of which is an oscillating motion of the needle block about an axis moving along the direction of the material layers to be joined, comprise an operating travel during which the needle (needles) being located in the material layers, takes said layers along in the conveying direction together with the claw, and a dead travel required to return the needle block and the claw to the starting point. In this known embodiment, half of each working cycle of the machine as far as the material layer feeding is concerned, is lostfor the return of the needle block and the conveying claw consequently the operating travel of the needle block along the conveying direction is equal to the stitchlength, in other words to the feed length of the fabric by each machine working cycle and the tendency to driving along variable length paths of the superposed material layers to be joined by stitching according to .the position thereof relative to the needle is all the more pronounced that the stitch length is long. Finally, as the needle block has a driving function for the article to be stitched and not only a stitch-forming function, said block must have a strong structure whichis consequently little suitable to high speeds. I

This invention has for object to obviate the drawbacks of the known solutions and to increase the machine operating speed. For this purpose in the machine according to the invention, the wheels are arranged sidewise relatively to the needle as considered along the stitching direction, the needle receives an oscillating movement along the stitching direction, between two positions lying on either side of a vertical plane that passes through the wheel axes, each one of said wheels is connected to a continuous drive member with the same circumferential speed, and the upper wheel is provided with a raising device to allow the feeding and pressing between the wheels of the material layers to be stitched.

It is to be understood that the combination of elements according to the invention allows a smooth synchronized continuous feeding of the material layers to be joined, makes use of the complete cycle for the feed ing of said-material layers, relieves the needle block from the stresses required for the driving and limits the operating travel of the needle along the conveying direction, to about half the stitch length this set of features allows machine operating speeds Well above the mean value, a speed of 5,500 revolutions per minute and more may be considered as a practical example.

In a particularly advantageous embodiment, the conveying wheels are arranged between the machine area with the needles and the inner stitch-forming members, and a housing inside which are arranged two driving members the one end of which projects outside the housing and bears a pinion for powering a driving pinion co-axial with the conveying wheel, the upper conveying wheel as well as the driving pinion thereof being rotatably mounted on a shaft supported by a cage which is rotatably mounted about the power pinion, said shaft being connected to a lever for raising the cage by rotating thereof about the power pinion.

Other details and features of the invention will stand out from the description given below by way of non limitative example and with reference to the accompanying drawings, in which FIG. 1 is an elevation view partly in section and with parts broken away, of a sewing machine according to the invention.

FIG. 2 is an end view partly in section of the machine shown in FIG. 1.

FIG. 3 is a section view with parts broken away, along line lII--III in FIG. 2.

FIG. 4 is a section view with parts broken away, along line IVIV in FIG. 1.

FIGS. 5a to 5d diagrammatically show the positions of the conveying wheels and of a needle by different moments in the operating cycle of the machine according to the invention.

In the various figures, the same reference numerals pertain to similar elements.

The sewing machine according to the invention comprises a housing 1 with a lower portion 1' inside which is supported a crank-shaft 2 which is driven by a shaft not shown and an upper portion 1" inside which is supported a main upper shaft 3 which is driven by a belt 4 from the crank-shaft 2.

The crank-shaft 2 has a throw 5 on which swings a rod 6 hinged to an oscillating lever 7 of an axis 8 which bears in turn a pair of hooks 9 which cooperate to form the stitch with on the one hand, a pair of needles 10 and on the other hand, a pair of spreaders 11 which are attached to an alternating-motion axis 12.

The needles 10 are attached to the end of a needle bar 13 with which they comprise the needle block the needle bar is slidingly' supported in a frame 14 which oscillates in a way described below. On the bar 13 is attached a small block 15 mounting the foot ofa lever 16 which is hinged on the other hand to a pivot 17 supported by a cam 18 which is made fast to the end of the main upper shaft 3. This set of members moves alternately the needles 10 along the direction of bar 13, in and out of the material layers of an article to be stitched, by passing through a needle plate 19 on the housing 1.

The frame 14 is arranged at the end of a shaft 20 which is supported by bearings in the housing 1 and at the other end of which is attached the foot of a lever 21 which is associated to an eccentric 22 mounted on the main upper shaft 3, This set of members causes the needle bar to oscillate about the axis of shaft 20.

The crank-shaft 2 bears a worm wheel 23 meshing with a worm 24 which is made fast to a shaft 25 extending in a plane at right angle to the shaft 2, slantwise from bottom to top between a level lying below the needle plate 19 and a level above said plate 19. The shaft 25 bears a pair of spaced worms 26,27 which each mesh with a worm wheel 28,29 respectively mounted on a shaft 30,31 in parallel relationship with the main shaft 2. Each one of said shafts 30,31 bears at that end thereof'projecting from the housing 1 which lies on the side of the stitch-forming members (needles 10, hooks 9, spreaders 11), a pinion 32,33 which meshes in turn with a larger- diameter pinion 34,35 which is integral with one of the superposed wheels 36,37 for conveying the material layers to be stitched.

The unit comprising the lower conveying wheel 36 and the pinion 34 is rotatably mounted on a shaft 38 which is supported by a cage 39 which is connected to the housing in 50 on that side opposite the wheel 36, the cage 39 supports through bearings 42 the shaft 30.

The unit comprising the upper conveying wheel 37 and the pinion is rotatably mounted on a shaft 40 which is fixedly mounted in a cage 41 which is rotatably mounted about the shaft 31 by means of bearings 43 the axis 40 projects inside a recess 44 of housing 1 where it bears the foot of a link 45 which is hinged on the other hand on a lever 46 which is supported by a pivot 47 projecting from the housing 1 the lever bears an operating handle 48 which allows to retract the conveying wheel 37 through rotating of the cage 41 and therewith of the unit comprised of the conveying wheel 37 and pinion 35 about the pinion 33 to allow the feeding of the material layers to be stitched between the conveying wheels 36,37.

The profile of the conveying wheel circumference is selected in any suitable way to provide driving without slipping of the material layers to be joined by stitching. The serrated showing in the drawings is not limitative. The construction allows moreover to exchange the wheels to adapt same to the kind of work to be performed. The lower conveying wheel 36 passes through the needle plate so as to enter in a way known from the usual conveying claws, the material layers to be stitched facing said wheel.

It is clear that in the machine according to the invention, the material layers are continuously driven on either side of the sewing plane by the conveying wheels 36,37 in the stitch-forming area, the needles 10 moving together with the material layers, at the same speed and along the same direction, from that moment where they enter said layers until the moment where they leave said layers. During the return travel of the needles to prepare for the formation of the following stitch, the material layers go on being fed in such a way that if as usual, the needles remain in the material layers during half the working cycle of the machine, the stitch length will be substantially twice as long as the needle path measured along the stitching line.

A working cycle of the machine according to the invention, corresponding to a 360 rotation of shafts 2 and 3, has been shown diagrammatically in FIGS. 5a to 5d.

In the 0 position, the plane of the needle bar is high and goes through the axis of the conveying wheels 36,37 the path of the end of needles 10 has been shown in dashed lines and the material piece to be stitched has been designated by refernce 51.

Between 0 and the needle bar goes down along part AB of the travel thereof, the piece 51 moving forward under the action of conveying wheels 36,37 over one fourth of the complete cycle displacement. Between 90 and the needle bar has reached the lowest travel point thereof, C, which is located on said axis while having moved forward together with piece 51 over one fourth of the complete displacement, measured in the plane of pieceSll. Between 180 and 270, the needle bar while still moving along the conveying direction of the material piece 51 to be stitched over one fourth of the complete displacement, has been raised up to level D where it comes out of said piece 51 between 270 and 360, the needle out of piece 51 goes up to point A while moving backwards relative to the conveying direction of piece 51, as said piece 51 goes on moving forward over the last fourth of the displacement thereof. A new cycle then starts again.

It must be understood that the invention is in no way limited to the above embodiements and that many changes may be brought therein without departing from the scope of the invention as defined by the appended claims.

1 claim 1. A sewing machine for stitching material layers, comprising:

at least one needle; and

two superimposed wheels for feeding the material layers;

an upper wheel; and

a lower wheel;

said upper and said lower wheels each mounted on a driving shaft with their axes of rotation in the same vertical plane horizontally parallel to each other; and

with the orbits of their circumference in pressure engagement with one another through the layers of said material separated by them;

means to rotate said wheels continuously at the same circumferential speed;

means to reciprocate said needle between two terminal positions, each said position located on the opposite side of said vertical plane; and

means to raise the upper wheel to allow the feeding and pressing of said material between the said wheels, to allow the feeding and pressing between the wheels of the material layers to be stitched;

further comprising:

a machine area, said at east one needle located within said machine area;

inner stitch forming members;

said wheels arranged between the said machine area and the said inner stitch forming members;

a housing;

two driving members each mounted inside the said housing with one end projecting outside the housing;

a driving pinion coaxially mounted with each said wheel;

a power pinion for powering said driving pinion;

a cage rotatably mounted about said power pinion;

a lever means for raising the said cage;

a shaft supported by said cage and connected to said lever for raising the cage by rotation thereof about the said power pinion;

said upper wheel and said driving pinion rotatably mounted on said shaft about the said power pinion.

2. A sewing machine as claimed in claim 1, which comprises a control shaft arranged slanting upwards inside said housing, crosswise relative to the driving shafts; said control shaft bearing two worms a pinion rotating together with one of said driving shafts;

said worms meshing with said pinions.

3. A sewing machine comprising:

a housing;

a rotary drive shaft disposed at least partially in said housing;

an upper work feeding rotary wheel;

a lower work feeding rotary wheel, which wheels form a pair of work feeding wheels in pressure contact with one another, having their axis of rotation arranged horizontally parallel one to the other and in the same vertical plane;

an upper and a lower rotating driving member, each for one of said work feeding wheels, said driving members extending from a region within said housing to a region external thereof; connection within said housing from said shaft for continuously rotating said driving members;

a first pinion means mounted on the end of each driving member which is external of the housing;

a second pinion means mounted co-axial with each work feeding wheel, each first pinion means being in driving engagement with one second pinion means to continuously rotate said work feeding wheels a cage rotatably mounted on that part of said upper driving member which is external of said housing, said upper work feeding wheel and its associated second pinion means being rotatably mounted on a shaft carried by said cage; and

connecting means between said cage and an operating lever to rotate said cage between a position wherein said upper work feeding wheel is'in pressure contact with said lower-work feeding wheel and a position wherein said upper work feeding roller is disengaged from contact with said lower work feeding wheel;

stitchrforming members comprising:

a reciprocating needle carrying bar extending in a vertical plane adjacent said working feeding wheels; and

means for oscillating said needle carrying bar for shifting the needle in the direction of feed whenever it is engaged with the work between two positions lying on either side of said vertical plane containing both wheels rotating axis.

4. A sewing machine comprising:

a housing; 1

a rotary drive shaft disposed at least partially in said housing;

an upper work feeding rotary wheel;

a lower work feeding rotary wheel, which wheels form a pair of work feeding wheels in pressure contact with one another, having their axis of rotation arranged horizontally parallel one to the other and in the same vertical plane;

connections from said shaft for continuously rotating said lower work feeding wheel;

a rotating driving member for said upper work feeding wheel;

said driving member extending from a region within said housing to a region external thereof; connection within said housing from said shaft for continuously rotating said driving member;

a first pinion means mounted on the end of said driving member;

a second pinion means mounted co-axial with said upper work feeding wheel;

said first and second pinion being in driving engagement to continuously rotate said upper work feeding wheel;

a cage rotatably mounted on that part of said upper driving member which is external of said housing, said upper work feeding wheel and its associated second pinion means being rotatably mounted on a shaft carried by said cage and connecting means between said cage and an operating lever to rotate said cage between a position,

wherein said upper work feeding wheel is in pressure contact with said lower work feeding wheel and a position, wherein said upper work feeding roller is disengaged from contact with said lower work feeding wheel;

stitch forming members comprising:

a reciprocating needle carrying bar extending in a vertical plane adjacent said work feeding wheels; and A means for oscillating said needle carrying bar for shifting the needle in the direction of feed whenever it is engaged with the work between two positions lying on either side' of said vertical plane containing both wheels rotating axis.

Claims (4)

1. A sewing machine for stitching material layers, comprising: at least one needle; and two superimposed wheels for feeding the material layers; an upper wheel; and a lower wheel; said upper and said lower wheels each mounted on a driving shaft with their axes of rotation in the same vertical plane horizontally parallel to each other; and with the orbits of their circumference in pressure engagement with one another through the layers of said material separated by them; means to rotate said wheels continuously at the same circumferential speed; means to reciprocate said needle between two terminal positions, each said position located on the opposite side of said vertical plane; and means to raise the upper wheel to allow the feeding and pressing of said material between the said wheels, to allow the feeding and pressing between the wheels of the material layers to be stitched; further comprising: a machine area, said at east one needle located within said machine area; inner stitch forming members; said wheels arranged between the said machine area and the said inner stitch forming members; a housing; two driving members each mounted inside the said housing with one end projecting outside the housing; a driving pinion coaxially mounted with each said wheel; a power pinion for powering said driving pinion; a cage rotatably mounted about said power pinion; a lever means for raising the said cage; a shaft supported by said cage and connected to said lever for raising the cage by rotation thereof about the said power pinion; said upper wheel and said driving pinion rotatably mounted on said shaft about the said power pinion.

2. A sewing machine as claimed in claim 1, which comprises : a control shaft arranged slanting upwards inside said housing, crosswise relative to the driving shafts; said control shaft bearing two worms ; a pinion rotating together with one of said driving shafts; said worms meshing with said pinions.

3. A sewing machine comprising: a housing; a rotary drive shaft disposed at least partially in said housing; an upper work feeding rotary wheel; a lower work feeding rotary wheel, which wheels form a pair of work feeding wheels in pressure contact with one another, having their axis of roTation arranged horizontally parallel one to the other and in the same vertical plane; an upper and a lower rotating driving member, each for one of said work feeding wheels, said driving members extending from a region within said housing to a region external thereof; connection within said housing from said shaft for continuously rotating said driving members; a first pinion means mounted on the end of each driving member which is external of the housing; a second pinion means mounted co-axial with each work feeding wheel, each first pinion means being in driving engagement with one second pinion means to continuously rotate said work feeding wheels ; a cage rotatably mounted on that part of said upper driving member which is external of said housing, said upper work feeding wheel and its associated second pinion means being rotatably mounted on a shaft carried by said cage; and connecting means between said cage and an operating lever to rotate said cage between a position wherein said upper work feeding wheel is in pressure contact with said lower work feeding wheel and a position wherein said upper work feeding roller is disengaged from contact with said lower work feeding wheel; stitch forming members comprising: a reciprocating needle carrying bar extending in a vertical plane adjacent said working feeding wheels; and means for oscillating said needle carrying bar for shifting the needle in the direction of feed whenever it is engaged with the work between two positions lying on either side of said vertical plane containing both wheels rotating axis.

4. A sewing machine comprising: a housing; a rotary drive shaft disposed at least partially in said housing; an upper work feeding rotary wheel; a lower work feeding rotary wheel, which wheels form a pair of work feeding wheels in pressure contact with one another, having their axis of rotation arranged horizontally parallel one to the other and in the same vertical plane; connections from said shaft for continuously rotating said lower work feeding wheel; a rotating driving member for said upper work feeding wheel; said driving member extending from a region within said housing to a region external thereof; connection within said housing from said shaft for continuously rotating said driving member; a first pinion means mounted on the end of said driving member; a second pinion means mounted co-axial with said upper work feeding wheel; said first and second pinion being in driving engagement to continuously rotate said upper work feeding wheel; a cage rotatably mounted on that part of said upper driving member which is external of said housing, said upper work feeding wheel and its associated second pinion means being rotatably mounted on a shaft carried by said cage ; and connecting means between said cage and an operating lever to rotate said cage between a position, wherein said upper work feeding wheel is in pressure contact with said lower work feeding wheel and a position, wherein said upper work feeding roller is disengaged from contact with said lower work feeding wheel; stitch forming members comprising: a reciprocating needle carrying bar extending in a vertical plane adjacent said work feeding wheels; and means for oscillating said needle carrying bar for shifting the needle in the direction of feed whenever it is engaged with the work between two positions lying on either side of said vertical plane containing both wheels rotating axis.

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