US3425377A

US3425377A - Sewing machine

Info

Publication number: US3425377A
Application number: US477572A
Authority: US
Inventors: Edward H Scharmer Jr
Original assignee: MINNEAPOLIS SEWING MACHINE Inc
Current assignee: Doboy Packaging Machinery Inc; MINNEAPOLIS SEWING MACHINE Inc
Priority date: 1965-08-05
Filing date: 1965-08-05
Publication date: 1969-02-04
Anticipated expiration: 1986-02-04

Description

'Feb. 4, 1969 E. H. SCHARMER, JR 3 SEWING MACHINE Filed Aug; 5, 1965 Sheet 5 of 6 INVENTOR. v fDWARD MJcmRMsRJR.

Feb. 4, 1969 E. H. SCHARMER, JR

SEWING MACHINE Filed Au 5, 1965 Sheet INVENTOR. fDWARD/IJZHARMERJR.

Feb. 4, 1969 E- H. SCHARMER, JR L 3,

SEWING MACHINE Sheet .Filed Aug. 5, 1965 R mm Wm mm n m M F.

SEWING MACHINE Filed Aug. 5, 1965 Sheet United States Patent Oflice 5 Claims ABSTRACT OF THE DISCLOSURE A sewing machine continuously driving and moving the material to be sewn and having a cooperating needle and looper producing the chain stitching; the needle being reciprocated into and out of the fabric, and being moved rectilinearly along with the fabric while inserted into the fabric; the looper coacting with the needle and producing stitching and moving with a rocking motion along and opposite to the direction of material travel and a slid- H ing motion transversely of the direction of travel and to opposite sides of the needle during the stitching.

This invention is concerned with production apparatus and more particularly with a sewing machine for sewing continuously moving materials.

It is often desirable to incorporate sewing apparatus into on-line or assembly line production techniques. When this is done, problems arise when the assembly line is run as a continuous belt or constant motion chain type line. Prior art sewing machines are generally of the type that do not sew continuously moving materials, but are designed to function with a stop-start or jerky motion of the materials. This is generally necessary in prior art sewing machines to prevent damage to the materials being sewn. That is, if the material moves while the needle is piercing it, the material will be damaged by pulling against the needle. Therefore, the machines stop the material while the needle is piercing it, and advance the material when the needle has been withdrawn.

An attempt to use these prior art sewing machines in continuous motion assembly line techniques has resulted in numerous breakdowns and other undesirable effects in the production line. The constant stop-start of the material by the sewing machine creates numerous disabling frictions and pressures in the continuous belt or chain which is feeding the material to the machine or removing it from the machine.

Some manufacturers have attempted to overcome this problem by providing a slanting trajectory to the sewing needle, or a zigzag motion to the sewing needle. While these improvements on the vertical trajectory sewing needle have somewhat alleviated the problem of damage to the material, they have not overcome the above mentioned problems in regard to continuously moving materials.

The apparatus of this invention overcomes the above mentioned problem by providing a rectilinear trajectory for the sewing needle. The needle moves in a rectilinear path which is both substantially perpendicular to the continuously moving materials and parallel to the direction of movement of the continuously moving materials.

In the sewing machine of this invention the sewing needle is oscillated vertically up and down in its stitching function. At the same time, the needle is translated in a horizontal back and forth motion to prevent damage to the moving materials. That is, as the sewing needle is in its downward stroke, to pierce the materials, the needle is at the same time translated in the direction of the materials so that the needle piercing the materials rides with it to prevent tearing or stretching of the stitch hole. The

3,425,377 Patented Feb. 4, 1969 horizontal motion continues in the direction of the moving materials during the withdrawal of the needle, and when the needle has been withdrawn the horizontal motion is reversed and the needle carried back to prepare for the next stitch stroke.

Briefly described, the sewing machine of this invention comprises a frame having mounted toward its forward end a pair of parallel, horizontally disposed guide rods. A first plate is slidably mounted on the rods for a horizontal back and forth motion. A set of slide bearings or journaling bearings are rigidly connected to the first plate for vertically carrying a needle bar which is to slide up and down in the bearings. An aperture is cut out of the first plate and a second pair of parallel guide rods are vertically disposed within the aperture. A second plate is slidably connected to the guide rods for vertical up and down sliding. The second plate is in substance a cam follower as it engages a cam which will impart motion to the first and second plates. The cam 'is in turn connected to a horizontally disposed shaft which is rotated by drive means mounted on the sewing machine frame. The needle bar, which carries the sewing needle at its lower end, is pivotally linked to the cam.

As the cam turns, it performs two functions. First, through the linkage to the needle bar it translates the needle bar in an up and down stitching motion. Second, it imparts cam force on the second plate. Since the second plate is restricted to vertical motion on the second pair of guide rods, the component of the cam force which cannot be taken up by sliding of the second plate is trans mitted to the first plate to impart a horizontal back and forth motion to the first plate. As the first plate slides on the first set of guide rods, it translates the needle bar back and forth. The back and forth motion and the vertical motion of the needle bar are synchronized to providethe above described rectilinear movement with respect to each sewing stroke.

Also included in the sewing machine of this invention is a looper mechanism for coacting with the sewing needle to stitch the materials. In the embodiment of this invention described below, the looper motion is synchronized to the sewing needle motion through cams connected to the same shaft which provides motion to the sewing needle.

Also provided are two pairs of rollers for providing continuous motion to the materials to be sewn. The rollers are mounted on either side of the sewing needle to advance the materials across the ledger plate in the sewing machine. In the embodiment described below, the lower of each pair of vertically disposed rollers is driven by a rotating mechansim mounted on the sewing machine frame. The upper roller of each pair is spring biased against the lower roller for grasping the materials between them, the spring tension being adjustable to accommodate various thicknesses of materials.

Another feature of this invention is a cutting knife for cutting the free running thread chain between a series of articles being sewn. The ledger plate is provided with an upwardly extending flange at the point where the sewn materials leave the sewing machine. A cutting bar is mounted adjacent to the flange and is oscillated along the outer edge of the flange. As the moving materials collide with the flange, they are forced upward and over the cutting knife to prevent cutting of the thread chain in the sewn materials. A notch in the fla-n'ge is provided in line with the thread chain. When there is no material present, and the thread chain is therefore free running, it will be passed through the notch rather than being forcednpward by the flange and will be cut by the oscillating cutting bar.

To assure that the free running thread chain passes through the notch to be cut, the second or last pair of rollers are mounted such that the vertical axis of the upper roller is closer to the notch than the vertical axis of the lower roller, to throw the thread chain downward.

This brief explanation of the aparatus of this invention will be more fully understood with reference to the accompanying drawings, specification and claims. It should be noted here that though the use of the apparatus of this invention has been described in relation to an assembly line technique, its use is not limited to such techniques, and the apparatus is highly adaptable to many uses.

In the drawings:

FIG. 1 is a front elevational view of the sewing machine of this invention, with the needle bar shown in the raised position;

FIG. 1A is a detailed sectional view taken along the line IA1A of FIG. '1;

FIG. 2 is a vertical longitudinal sectional view of the apparatus of this invention taken along the line 22 of FIG. 4, in which the needle bar is shown in the lowered position, with the looper fully retracted;

FIG. 3 is a cross-sectional elevational view taken along the line 3-3 of FIG. 2, but showing the component parts of this sewing machine in the position of FIG. 1;

FIG. 4 is a plan sectional view taken along the line 44 of FIG. 2, with the component parts of the sewing machine in the position of FIG. 1;

FIG. 5 is a partial side elevation with components broken away and depicting the control apparatus for a thread cutting bar;

FIG. 5A is a schematic view illustrating how the free running thread chain automatically positions itself to be cut by the cutting bar; and

FIGS. 6A, 6B, and 6C are schematic views illustrating the rectilinear movement of the sewing needle with respect to the continuously moving materials.

Referring to FIGS. 1 through 4, there is disclosed a sewing machine indicated generally at 10'. Rigidly mounted in a forward portion of frame 10 are a pair of

guide rods

14 and 25. A plate 80 is slidably mounted on

guide rods

14 and 25. Within an aperture in plate 80 are rigidly mounted a vertical, parallel pair of

guide rods

49 and 50. A plate 81 is slidably mounted on guide rods 49 and '50. A pair of

parallel arms

82 and 83 extend forwardly from plate 80. A journal or slide bearing 15 is vertically disposed in arm 83, and a journal or slide bearing 16 is vertically disposed in arm 82. A needle bar 11 is positioned within

slide bearings

15 and 16 for up and down journaling thereby. A threadable needle [12 is connected to the lower end of needle bar 11.

A rotatable shaft 51 is rotatably mounted between frame 10 and a member 54. Shaft 51 extends through frame 10 for connection to suitable rotational drive means (not shown). Mounted on shaft 51 for rotation thereby are a pulley 52 and a gear 53. A horizontally disposed shaft 70 is rotatably mounted in frame 10. A

pulley 68 is mounted on shaft 70 in line with pulley 52. A pulley 67 is mounted on frame 10 in line with

pulleys

52 and 68. A belt 66 is mounted on

pulleys

52, 67 and 68, for providing rotation of shaft 70 due to rotation of shaft 51. An eccentric or cam 75 is connected to the end of shaft 70 for rotation the'reby. Eccentric 75 is engaged by plate 81 for motion of

plates

81 and 80 imparted by eccentric 75. A connecting pin 76 is shown connected to eccentric 75. An arm 77 is rigidly connected to pin 76 at one end. Arm 77 is pivotally connected at another end to one end of another arm 79 by a pin 78. The other end of arm 79 is rigidly connected to needle bar 11 by a clamp 17. Thus motion of eccentric 75 is translated through the linking

arms

77 and 78 to provide motion to needle bar 11. i

There is also shown a looper shaft 98 slidably and rotatably mounted between a pair of

members

62 and 99. Attached to looper shaft 98 is a threadable looper 47 which coacts with needle 12 to sew materials. A cam 73 mounted on shaft 70 for rotation thereby, is engaged by a cam follower 101. Cam follower 101 is connected by a rod 102 to a bearing 104 connected by a clamp 1105 to looper shaft 98. When shaft 70 is rotated the subsequent movement of cam 73 is translated through cam follower 101, rod 102, bearing 104 and clamp 105 to arcuately oscillate looper shaft 98. Also connected to shaft 70 is another cam 71 engaged by a cam follower 91. Cam follower 91 is connected by a rod 92 to a pivot bolt 93. Pivot bolt 93 is also connected to a leg of a teeter member 94 which is rigidly connected to a shaft 95. Shaft is rotatably mounted in frame 10. Another leg of member 94 is connected to a ball 96 within a ball and socket bearing of which a socket 97 is connected to shaft 98. Thus rotation of shaft 70 and the subsequent rotation of cam 71 is translated by cam follower 91, rod 92, member 94, ball 96 and socket 97, to provide forward and back sliding of looper shaft 98.

To provide continuous motion of materials to be sewn, indicated generally at :13, there is shown a first pair of

roller Wheels

21 and 22 for driving materials 13 into proximity with sewing needle 12, and a second pair of

roller wheels

23 and 24 to move materials away from proximity with needle 12. A ledger plate '89 is provided across which materials 13 are driven for sewing. In addition to an aperture in ledger plate 89 through which needle 12 can pass to coact with looper 47 to stitch materials 13, there are apertures provided in ledged plate 89 to allow

lower wheels

22 and 24 to meet, respectively, with

upper wheels

21 and 23. Wheel 21 is spring biased against wheel 22 by spring means here shown as leaf spring 28. Spring 28 is suported by a bolt 86 connected by a bearing 74 to shaft 70, and by a bolt 87 connected by a bearing 72 to shaft 70. Spring 28 is biased against a vertically held rod 26 connected at one end to the axle of wheel 21. Rod 26 is journaled for vertical sliding by a pair of

slide bearings

31 and 33 connected to frame 10. The spring bias of wheel 21 against wheel 22 is adjustable by adjustment of

bolts

86 and 87. The vertical movement of rod 26 is restricted by a member 32 having one end clamped to rod 26, and having an arm extending into a slot 37 in a member 38. Member 38 is connected to frame 10 by bolts 41, as shown in FIG. 1A. Member 32 is connected to rod 26 by a screw 40, also shown in FIG. 1A.

Wheel 23 is spring biased against wheel 24 in a manner similar to that of wheel 21 against wheel 22. A spring 29, here shown as a leaf spring, is carried by shaft 70 in the same manner as described above for spring 28. Spring 29 bears down on a vertically held rod 27 which is connected at its lower end to the axle of Wheel 23. Rod 27 is journaled in a pair of

slide bearings

34 and 36 conconnected to frame 10. A member 35 is clamped at one end to rod 27, and has an arm extending through a slot in a member 39 which is similar to slot 37 in member 38. Member 39 is connected to frame 10 by means of a pair of bolts 42. Also cooperating with the two pair of wheels to hold the material 13 for sewing, are a pair of arms 44 and 44'. Arms 44 and 44' are connected at one end to the axle of wheel 21, and have another end spring biased by springs 45 and 45', respectively, toward ledger plate 89.

Gear 53 on shaft 51 is engaged with a gear 55, which is in turn mounted on a shaft 56 rotatably connected between frame 10 and member 54. Shaft 56 is extended through a member 57 and terminates in a gear 58 mounted thereon. Gear 58 is engaged by a gear 59 mounted on a shaft 61. Shaft 61 is rotatably mounted in member 57, a member 62 and a frame 10. A shaft 106 is mounted parallel to shaft 61 in member 62 and frame 10. Wheel 22 is mounted on shaft 61, while wheel 24 is mounted on shaft 106. A pulley or gear 107 is mounted on shaft 61, while a pulley or gear 108 is mounted on shaft 106 in line with pulley or gear 107. A chain or belt 109 is connected around pulleys or gears 107 and 108. Thus rotation of shaft 51 by the external drive means is translated by

gears

53, 55, 58 and 59 to shaft 61. Rotation of shaft 61 will cause rotation of wheel 22, and also will cause rotation of shaft 106 to rotate wheel 24 due to the action of pulleys or gears 107 and 108 connected by chain or belt 109.

In FIG. 1 there is shown attached to frame a thread spool holding means 19 on which thread 20 is mounted. Thread 20 is then threaded through a thread mount 18, and thence through needle 12. Thread is also carried to and threaded through looper 47 in the usual manner (not shown).

Referring now to FIGS. 1, 4, 5, and 5A, there is shown additional mechanism of the apparatus of this invention for cutting free running thread chain between a series of sewn articles. ledger plate 89 is shown as having an upwardly extending or beveled flange 90 at the end thereof where sewn materials come off. Flange 90 is provided with a notch 115 in line with a thread chain 100 created by the stitching coaction of needle 12 and looper 47. A cutting arm 113 is provided with a cutting edge 114. Cutting bar 113 is pivotally mounted to frame 10' by an adjustment spring means 103, such that arcuate oscillation of cutting bar 113 causes cutting edge 114 to pass back and forth adjacent to notch 115.

A member 110 has one end rigidly connected to rotatable shaft 95, and another end pivotally connected to one end of a rod 111. Rod 111 has another end pivotallly connected to cutting bar 113 by a pivot bolt 112. Thus as shaft 95 is rotated by the action of the cam 71, cam follower 91, rod 92 and teeter arm 94, the motion of shaft 95 will be translated by member 110 and rod 111, to oscillate cutting bar 113 as best shown in FIG. 5.

In FIGS. 1 and 5A it is apparent that wheel 23 has its vertical axis mounted closer to flange 90 than is the vertical axis of wheel 24. Thus materials 13 and thread chain 100 passing between

wheels

23 and 24 will be cast downwardly upon leaving the grasp of

wheels

23 and 24. Materials containing thread chain 100- will be deflected over cutting bar 113 by flange 90, while free running thread chain 100 will continue downwardly through notch 115 to be cut by bar 113.

In operation, materials to be sewn 13 are fed onto ledger plate 89 where they are grasped between

roller wheels

21 and 22. Materials 13 are firmly grasped between

Wheels

21 and 22 due to spring 28 applying a downward pressure on rod 26 to force wheel 21 toward wheel 22. The rotation of shaft 51 is translated through

gears

53 and 55 to shaft 56, thence to gear 58 and through gear 59 to rotate shaft 61. The continuous rotation of shaft 61 causes continuous rotation of roller wheel 22, the rotation being counterclockwise with respect to the front view of the sewing machine of this invention. Thus materials 13 are continually fed by

roller wheels

21 and 22 into proximity with needle 12 and looper 47.

As materials 13 are forced across ledger plate 89 they are stitched by the coaction of needle 12 and looper 47 in a manner to be described below. The continuously moving materials 13 are then grasped between

roller wheels

23 and 24, wheel 23 being yieldingly biased against wheel 24 by means of spring 29 forcing downward on rod 27. The continuous rotation of shaft 61 is felt by shaft 106 due to the translation effect of gears or pulleys 107 and 108, connected by belt or chain 109. Thus shaft 106 is continuously rotated to rotate Wheel 24. Materials 13 are therefore continuously moved out of proximity With needle 12 by the action of

wheels

23 and 24.

To avoid damage to materials 13 during stitching or sewing, a rectilinear motion is imparted to needle bar 11 and thus needle 12. A horizontal movement of needle bar 11 is accomplished through

plates

80 and 81, while a vertical movement of needle bar 11 is accomplished through the linked

arms

77 and 79. The continuous rota- 6 tion of shaft 51 is translated to shaft 70 by belt 66 which is connected around pulleys 52, 67 and 68, pulley 68 being connected to shaft 70.

As shaft 70 rotates it will rotate eccentric 75. Plate 81 is engaged with eccentric 75 and may be described as acting as an eccentric follower. However, plate 81 essentially has only one degree of freedom. That is, plate 81 may only slide up and down vertically on

guide rods

49 and 50. Therefore, only the vertical component of force exerted 'by eccentric 75 on plate 81 is accounted for in motion by plate 81. The horizontal component of force exerted by cam 75 on plate 81 is therefore felt by plate 80. Plate has only a horizontal degree of freedom and will slide back on forth horizontally on

guide rods

25 and 14 as force is exerted by eccentric 75 on plate 81. As

arms

82 and 83 are rigidly connected to plate 80, needle bar 11, which is mounted in

slide bearings

15 and 16 in

arms

83 and 82, respectively, will be carried horizontally back and forth with the motion of plate 80.

At the same time the above described actions are taking place to horizontally translate needle bar 11 back and forth, needle bar 11 is also being translated vertically up and down, and journaled by

slide bearings

15 and 16. This latter motion is also directly related to the rotation of eccentric 75. Arm 77 is rigidly connected to pin 76 on eccentric 75. As eccentric 75 rotates, arm 77 will also 'be caused to rotate. This will cause motion of arm 79 which is pivotally linked to arm 77 through pin 78. As arm 79 moves it will impart motion to needle bar 11 through the pivotal clamp 17. This motion of needle bar 11 is journaled through

slide bearings

15 and 16 to be a vertical up and down motion.

The above description of the motion of needle bar 11 may be more fully understood by reference to FIGS. 6A, 6B, and 6C. The three figures are schematic views illustrating how needle 12 follows the direction of travel of materials 13 as it moves leftwardly in the direction shown by the horizontal arrow. In FIG. 6A needle bar 11 and needle 12 are shown in a downward stroke as shown by the vertical arrow. As eccentric 75 rotates counterclockwise, arm 77 will also be carried in a counterclockwise motion. Here arm 77 is shown in a substantially horizontal position extending leftwardly. As arm 77 is continued in its counterclockwise path its motion will be translated through arm 79 to needle bar 11, and needle bar 11 will be forced downwardly due to the pivotal connection of arm 79 to clamp 17.

Slide bearings

15 and 16 will journal the motion of needle bar 11 vertically.

Simultaneously, eccentric 75 is exerting a force on plate 81 engage therewith, the horizontal component of the force causing a motion of plate 80 on

horizontal guide rods

14 and 25. As shown in FIG. 6A, cam 75 is at a position where essentially all of the force exerted on plate 81 is vertical, causing an upward sliding of plate 81. Before needle 12 enters materials 13, eccentric 75 will have rotated sufficiently to commence a leftward horizontal slide of plate 80, to thus translate needle bar 11 and needle 12 in a leftward direction parallel to the continuous motion of materials 13.

In FIG. 6B, eccentric 75 has rotated sufficiently to cause needle 12 to pierce materials 13 and be at its lowest most position. At this

point arms

77 and 78 are in a substantially vertical line. In FIG. 6B eccentric 75 is shown in a position such that essentially all of the force exerted on plate 81 is a horizontal force, and plate 81 will essentially translate all of this force to continue the horizontal leftward slide of plate 80, needle bar 11, and needle 12, to avoid damage of the pierced materials 13.

In FIG. 6C needle bar 11 and needle 12 are shown in an upward motion as depicted by the vertical arrow. Needle 12 has been removed from continuously moving materials 13, and it is no longer necessary to continue the leftward horizontal motion of needle bar 11.

Therefore, eccentric 75 is shown in a position where essentially all force on plate 81 is vertical and plate 81 is commencing a downward slide on

guide rods

49 and 50. As eccentric 75 continues to rotate from this point it will exert a horizontal component of force which will be felt on plate 80, to cause plate 80 to horizontally slide back on guide rods 14 and to its original position, in preparation for the next stitching cycle.

Arm 77 is shown extending substantially horizontally to the right as it continues in its counterclockwise rotation. As the rotation of arm 77 continues, it will be followed by arm 78 to pull needle bar 11 and needle 12 upwardly.

Thus the stitching cycle of needle 12 is accomplished with a rectilinear motion. The vertical up and down portion of the rectilinear motion is substantially perpendicular to the continuously moving materials 13 which it is desired to sew. At the same time, the horizontal portions of the rectilinear motion are substantially parallel to the direction of continuous motion of materials 13, with the parallel motion being in the direction of travel of materials 13 during the time that needle 12 is entering and leaving materials 13, to avoid damage.

To accomplish stitching, it is necessary that looper 47 coact with needle 12 as it pierces materials 13. This is done with a simultaneous arcuate oscillation and forward and back oscillation of looper 47. The necessary coaction is well known to those skilled in the art. To provide the proper coaction in view of the rectilinear motion of needle 12, it is only necessary to broaden the arcuate oscillation of looper 47.

It is desirable to synchronize the motion of looper 47 with that of needle 12. In the preferred embodiment described herein, synchronization is accomplished by driving looper 47 from the same shaft 70 which drives eccentric 75 to provide motion to needle 12. Cam 73 is driven by shaft 70 and imparts motion to cam follower 10-1. The motion of cam follower 101 is translated by rod 102 to wobble bearing 104 connected to looper shaft 98. This may best be seen by reference to FIGS. 2 and 3. As shaft 70 continuously rotates, it will cause continuous rotation of cam 73, which will in turn drive cam follower 101 in an up and down motion which will be felt through rod 102 at bearing 104. As bearing 104 is translated up and down, because it is connected at the side of shaft 98 it will cause an arcuate oscillation or back and forth rotation of shaft 98, which will in turn be felt by looper 47.

At the same time, cam 71 will be continuously rotated by shaft 70 to impart an up and down motion to cam follower 91 which will be translated through rod 92 to one leg of teeter member 94. Thus teeter member 94 will cause rotation of shaft 95 and at the same time cause a teeter motion of the other arm of teeter member 94, to cause forward and back motion of ball 96. As ball 96 is translated forward and back in socket 97, it will cause a forward and back motion of looper shaft 98 which will in turn be felt by looper 47. Thus the arcuate and forward and back oscillations of looper 47 are both originated by shaft 70, to thus synchronize the motion of looper 47 with needle 12.

The drawings illustrate the linkage and movement of the looper 47. It will be seen that in the coordinated movement of the needle 12 and looper 47, the needle moves downwardly toward and into the fabric during the initial part of the operating cycle, and as the needle initially pierces the material 13, the looper 47 is disposed at one side of the needle and has been moved axially in the direction of shaft 98 so as to lie closely adjacent the needle and extending therebeyoud. As the needle continues to move downwardly, the looper progressively returns in the axial direction of shaft 98. As the needle is moving downwardly through the fabric 13, the cam 75 is operating to move the needle in the direction of material travel. Review of the mechanism illustrated will then be seen to cause the looper 47, after it has retracted beyond the needle as illustrated in FIG. 2, to rock over, along the direction of material travel from the position illustrated in FIG. 6A to the position shown first in FIG. 6B and then in FIG. 60 so that while the needle remains in the fabric and extended downwardly along the looper, the looper may be moved axially of shaft 98 to extend along the opposite side of the needle 12 again while the needle still remains in the fabric. Of course, at this instant the needle is actually moving up and preparing to withdraw from the material 13. The needle and looper move sufliciently close to each other as is illustrated in order to produce a coaction of the threads carried by the looper and the needle in producing a chain stitch, which is oftentimes refered to as a double lock chain stitch. The stitch is completed and preparation is made for the next stitch being formed after the needle 12 has been withdrawn from the material at which time the mechanism will be seen to produce a rocking of the looper back to its original position, opposite to the direction of material travel and from the position illustrated in FIG. 6C to that shown in FIG. 6A. In this last mentioned rocking movement, it will be obvious that the looper 47 rocks across the path of needle reciprocation without interfering with the needle as the needle is at that instant in its upwardly retracted position. The looper is required to momentarily and alternately slide along opposite sides of the needle during each stitching operation, and this mechanism accommodates this motion and also accommodates the transverse movement of the needle 12 as the needle moves with the material 13 while projected into the material, and returns in the opposite transverse direction opposite to the direction of the material travel when the needle has been withdrawn.

An additional feature of the embodiment of the invention described herein is an automatic thread cutting knife for cutting free running thread between a series of sewn articles. To accomplish this cutting, the beveled edge of flange on ledger plate 89 is provided, along with notch 115, and cutting bar 113. Arm 110 is rigidly connected at one end to shaft so that it will be oscillated as shaft 95 is oscillated in the manner described above for forward and back oscillation of looper shaft 98. The motion of arm is translated to cutting bar 113 to cause cutting edge 114 to pass back and forth across notch 115, and below the top of flange 90.

As may best be seen by FIG. 5A, materials 13 which have been sewn and contain thread chain 100, are directed upwardly by flange 90 to pass over the oscillating cutting edge 114. However, when thread chain 100 is free running, it will be passed through notch to be cut by cutting edge 114.

In the preferred embodiment of the invention, to assure cutting of free running thread chain 100, it is cast downwardly by

wheels

23 and 24 due to the vertical axis of wheel 23 being closer to flange 90 than is the vertical axis of wheel 24. This causes thread chain 100 to come out of the grasp of

wheels

23 and 24 with a downwardly directed force, causing it to fall into notch 115 and be positioned for easy cutting. The offset of

wheels

23 and 24 does not appreciably effect the trajectory of materials 13 as they will still be cast upwardly when striking beveled edge 90.

Spring loaded adjusting means 103 is provided to adjust the position of cutting bar 113 adjacent notch 115. Adjustment of the length of rod 111, for example, can be used to change the time during each period of oscillation at which cutting edge 114 crosses notch 115, to thus vary the point between a series of materials 13 at which thread chain 100 is cut.

From the foregoing description it is apparent that the apparatus of this invention provides a novel means for sewing continuously moving materials. Though specific structure has been described in connection with this preferred embodiment to provide a rectilinear motion to the sewing needle to prevent damage to the continuously moving materials, it should be understood that it is not intended to limit the scope of this invention to the specific structure claimed. Rather the structure of the preferred embodiment is merely exemplary of many mechanical means which could be used to impart the proper rectilinear motion to the sewing needle, that proper motion being simultaneously perpendicular and parallel to the direction of continuous movement of materials to be sewn.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Sewing machine apparatus for sewing continuously moving materials comprising:

a frame;

rotation imparting drive means mounted on said frame;

a shaft rotatably mounted on said frame and connected to said drive means for rotation thereby;

an eccentric connected to said shaft and adapted to be rotated thereby;

a first pair of guide rods connected to said frame and extending substantially horizontally within said frame;

a first plate slidably mounted on said first pair of guide rods;

said first plate defining an aperture therein;

a substantially vertically extending second pair of guide rods connected within said aperture;

a second plate slidably mounted on said second pair of guide rods;

said second plate engaging said eccentric, so that as said shaft rotates, said eccentric drives said second plate up and down on said second pair of guide rods and drives said first plate back and forth on said first pair of guide rods;

a first arm having one end rigidly connected to said eccentric;

a second arm having one end pivotally connected to the other end of said first arm;

a needle bar including means for connecting a sewing needle thereto;

means pivotally connecting the other end of said second arm to said needle bar;

journaling means rigidly connected to said first plate;

said needle bar being vertically and slidably mounted in said journaling means, so that as said eccentric rotates the motion of said first and second arms drives said needle bar up and down within said journaling means, said needle bar simultaneously being driven back and forth with the motion of said first plate on said first pair of guide rods;

a sewing needle connected to said needle bar and extending downwardly therefrom;

means mounted on said frame for continuously moving material to be sewn beneath said sewing needle; and

looper means mounted on said frame for coacting with said sewing needle to sew said materials.

2. The sewing machine apparatus of claim 1 in which said means for continuously moving materials to be sewn comprises:

first and second pairs of rollers;

each of said pairs of rollers comprising an upper and lower roller, means resiliently biasing said upper roller against said lower roller;

drive means connected to each of said lower rollers for rotating said lower rollers;

said first pair of rollers being adapted to receive materials to be sewn between said upper and lower rollers and continuously drive the materials into proximity with said sewing needle; and

said second pair of rollers being adapted to receive the sewn materials between said upper and lower rollers and continuously drive the materials out of proximity with said sewing needle.

3. The sewing machine apparatus of claim 2 including means for adjusting the resilient bias on each of said upper rollers to adapt said first and second pair of rollers to receive various thicknesses of materials to be sewn.

4. The sewing machine apparatus of claim 1 in which said looper means includes means for synchronizing the coaction of said sewing needle and said looper means comprising:

first and second cams mounted on said shaft and adapted to be rotated thereby;

first and second cam followers engaging, respectively, said first and second cams;

a looper shaft including said looper connected to one end thereof;

means slidably and rotatably mounting said looper shaft on said frame;

a first rod having one end connected to said first cam follower and another end connected to said looper shaft; and

a second rod having one end connected to said second cam follower and another end connected to said looper shaft, so that rotation of said shaft drives said first rod to arcuately oscillate said looper shaft and drives said second rod to slide said looper shaft back and forth.

5. Sewing apparatus for sewing continuously moving materials comprising:

a frame;

drive means mounted on said frame;

an eccentric means connected with said shaft for rotation thereby;

needle bar mounting means engaging said eccentric for movement thereby;

a needle bar vertically and slidably mounted to said needle bar mounting means, and including a sewing needle mounted at a lower end thereof;

linkage means connected between said eccentric and said needle bar, so that rotation of said eccentric causes back and forth horizontal movement of said needle bar carried by said needle bar mounting means, and simultaneous up and down sliding of said needle bar driven by said linkage means;

looper means mounted on said frame and connected to said drive means for coaction with said horizontal and up and down movement of the sewing needle to sew materials;

said drive means synchronizing the motion of said looper means with the motion of said sewing needle on said needle bar, said looper drive means comprismg:

a looper bar including a looper connected to one end thereof, said looper bar being movably mounted on said frame in a horizontal disposition transversely of the direction of material travel;

first and second cams connected to said shaft for rotation thereby;

a first cam follower engaging said first cam;

means connecting said first cam follower to said looper bar for oscillating arcuate movement of said looper connected to said looper bar and in directions along and opposite to the direction of material travel;

a second cam follower engaging said second cam;

and

means connecting said second cam follower to said looper bar for sliding movement of said looper connected to said looper bar and in a horizontal direction transversely of the direction of material travel, the movements of said looper and said sewing needle thus being synchronized by their actuation from the same shaft, and

1 l 1 2 means for continuously moving materials to be sewn 1,162,696 11/1915 Jerram 112-213 horizontally beneath said needle bar along the line 1,450,456 4/1923 Seymour 112213 of the back and forth horizontal movement of said 1,715,119 5/1929 Clarkson 112-221 XR needle bar. 2,207,141 7/1940 Zonis 112-159 References Cited 5 H HAMPTON HUNTER P E M -m r xa UNITED STATES PATENTS a y r 397,579 2/1889 Bartlett et al 112 213 US. C

925,320 6/1909 Fales ..112159 112-214, 252