US3023721A

US3023721A - Needle guards for sewing machine loop takers

Info

Publication number: US3023721A
Application number: US4379A
Authority: US
Inventors: Ralph E Johnson
Original assignee: Singer Co
Current assignee: Singer Co
Priority date: 1960-01-25
Filing date: 1960-01-25
Publication date: 1962-03-06
Anticipated expiration: 1979-03-06

Description

March .6, 1962 R. E. JOHNSON NEEDLE GUARDS FOR SEWING MACHINE LOOP TAKERS 6 Sheets-Sheet 1 Filed Jan. 25, 1960 JNVENTOR RALPH E. Jam/son WITNESS March 6, 1962 R. E. JOHNSON NEEDLE GUARDS FOR SEWING MACHINE LOOP TAKERS Filed Jan. 25, 1960 6 Sheets-Sheet 2 INVENTOR RALPH E. JOHNSON WITNESS TORN'EY March 6, 1962 R. E. JOHNSON 3,023,721

NEEDLE GUARDS FOR SEWING MACHINE LOOP TAKERS Filed Jan. 25, 1960 6 Sheets-Sheet 3 IIVNVENTOR. RALPH E. Jomvsou WITNESS BY W Z4B%M/L ATTORNEY March 6, 1962 R, E, JOHNSON 3,023,721

NEEDLE GUARDS FOR SEWING MACHINE LOOP TAKERS Filed Jan. 25, 1960 s Sheets-Sheet 4 II/II/IIIIIII'IIIIII 4 INVEN TOR. RALPH E. Jomvsou March 6, 1962 R. E. JOHNSON 3,

NEEDLE GUARDS FOR SEWING MACHINE LOOP TAKERS Filed Jan. 25, 1960 6 Sheets-Sheet 5 Fig. I2.

INVENTOR. RALPH E. JOHNSON WITNESS ATTORNEY March 6, 1962 R. E. JOHNSON 3,023,721

NEEDLE GUARDS FOR SEWING MACHINE LOOP TAKERS Filed Jan. 25, 1960 6 Sheets-Sheet 6 IN VEN TOR.

RALPH E. JOHNSON BY AT OR/VE) nited States Patent() 3,023,721 NEEDLE GUARDS FOR SEWING MACHINE LOOP TAKERS Ralph E. Johnson, Mountainside, N.J.. assignor to The Singer Manufacturing Company, Elizabeth, NJ., a

corporation of New Jersey Fiied Jan. 25, 1960, Ser. No. 4,379 11 Claims. (Cl. 112-184) The present invention relates to a loop taker for sewing machines and particularly to a loop taker of the vertical axis oscillating hook type.

The object of this invention is to provide a sewing machine loop taker of the vertical axis oscillating hook type that is economical in that it is inexpensive to manufacture and to assemble, in which the thread carrier and the bobbin are easy to remove and to replace, and which efficiently and dependably performs its intended function of concatenating a needle thread with a bobbin thread with a minimum of thread breakage, thread jamming, skipped stitches, and improper stitch formation.

A particular object of the present invention is to provide a new and improved needle guard.

Having in mind the above and other objects that Will be evident from an understanding of this disclosure, the invention comprises the devices, combinations and ar rangements of parts as illustrated in the presently preferred embodiment of the invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings in which:

FIG. 1 is a vertical sectional View longitudinally of a sewing machine embodying the present invention.

FIG. 2 is a vertical sectional view taken substantially on the line 22 of FIG. 1.

FIG. 3 is a bottom plan view of the sewing machine of FIG. 1.

FIG. 4 is a fragmentary top plan view of the hook mechanism of the sewing machine of FIG. 1 with the bobbin removed and a portion of the hook broken away.

FIG. 5 is a fragmentary vertical sectional view taken substantially on the line 5-5 of FIG. 4.

FIG. 6 is a fragmentary top plan View similar to FIG. 4 but with the bobbin carrier removed and a portion of the hook broken away.

FIG. 7 is an exploded perspective view of the parts of the hook mechanism.

FIG. 8 is a fragmentary detail view on an enlarged scale of the needle guard.

FIG. 9 is a top plan view of the bobbin carrier per se.

FIG. 10 is a side elevation view of the bobbin carrier per se.

FIG. 11 is a bottom view of the bobbin carrier per se.

FIG. 12 is a detail sectional view taken substantially on the line 12-12 of FIG. 4 with the released position of the bobbin case retaining means illustrated in phantom.

FIG. 13 is a view similar to FIG. 4 and illustrating the operation of the hook with the parts shown in the loop seizing position.

FIG. 14 is a sectional view taken substantially on the line 1414 of FIG. 13.

FIG. 15 is a view similar to FIG. 13 but with the parts shown in the loop cast-off position.

FIG. 16 is a view similar to FIG. 13 but with the parts shown just before the stitch setting position.

FIGS. 17, 18, 19 and are sequential detail sectional views illustrating the operation of the needle guard with the needle in the right position of the zigzag pattern.

FIGS. 21, 22 and 23 are sequential views similar to FIGS. 1720 but with the needle in the left position of the zigzag pattern.

ice.

With reference to the drawings, there is illustrated a sewing machine having a frame including a bed 1, a standard 2 rising from one end of the bed and carrying a bracket arm 3 that terminates in a head 4 overhanging the bed 1. The top of the bed '1 is formed by a bed plate 5 having an upper surface that forms the Work supporting surface 6 of the machine.

Journaled longitudinally of the bracket arm 3 is a main shaft 7 that is driven by an electric motor 8 mounted in the standard 2 and connected by a belt 9 to a hand wheel 10 on the end of the main shaft 7.

Work is fed across the work supporting surface 6 of the bed 1 by a feeding mechanism comprising a feed bar 11 pivotally mounted at its front end on a rock arm 12 that is upstanding from a feed advance shaft 13 journaled longitudinally in the front of the bed 1. Oscillation is imparted to the feed advance shaft 13 by a pitman 14 disposed vertically in the standard 2 and connected at its lower end by a crank 15 to the feed advance shaft 13 and connected at its upper end to an eccentric 16 on the main shaft 7. Intermediate its ends the pitman 14 has a laterally extending slide 17 received within a channel 18 in a block 19 pivotally mounted by a stud 20 in a partition 21 in the frame. The block 19 is adjustable by means of a lever 22 projecting from the block 19. Oscillation im parted to the pitman 14 by the eccentric 16 is converted to endwise motion by the slide 17, the amplitude of which motion is adjustable by means of the lever 22 to vary the angular position of the block 19 and thus the. channel 18 about the axis of the stud 20.

Feed lift motions are imparted to the feed bar 11 by a feed lift shaft 23 journaled longitudinally in the back of the bed 1 and having a crank arm 24 connected by a link 25 to the feed bar 11. The feed lift shaft 23 is oscillated by means of a second crank arm 26 carrying a cam follower 27 that tracks an axial displacement cam surface 28 on the top of a crank 29. The feed lift shaft is biased to its lowered position by a spring 30 which also holds the cam follower in engagement with the cam surface 28. The crank 29 is secured on the lower end of a vertical axis shaft 31 mounted in the standard 2 and rotated by the main shaft 7 through

meshing gears

32 and 33.

The feed bar 11 carries a feed dog 34 that operates through a slot 35 in a throat plate 36 which is provided in the bed plate 5 and which has an upper surface that also forms a part of the work supporting surface 6 of the machine. The work is held down against the throat plate 36 and the feed dog 34 by a presser foot 37 mounted on the lower end of a presser bar 38 mounted for endwise sliding in the head 4 and biased toward the work supporting surface by a spring 39. Actuation of the feeding mechanism advances the work across the work supporting surface 6 of the machine to define the line of feed of the machine.

A needle bar 40 is mounted in the head 4 for endwise reciprocation and at its lower end carries a needle 41 that is adapted to penetrate the work supporting surface 6 of the machine to define the point of stitch formation thereon. Endwise reciprocation is imparted to the needle bar 40 by a crank 42 on the end of the main shaft 7 and connected by a link 43 to a collar 44 on the needle bar. To provide for movement of the needle 41 laterally 0f the line of feed to define a zigzag or ornamental stitch pattern, the needle bar 49 is mounted in a needle bar gate 45 that is mounted for pivotal movement on a pivot rod 46 secured in the front of the head 4. Pivotal movement is imparted to the needle bar gate 45 to shift the needle 41 laterally of the line of feed by a cam actuated zigzag mechanism in the bracket arm 3 and driven from the main shaft 7, the mechanism including a replaceable stitch pattern cam 47 that actuates an oscillating element 48 which is adjustably connected by a pitman 49 to the needle bar gate 45.

Cooperating with the needle 41 in the formation of lock stitches is a loop taker, or more particularly, a vertical axis oscillating hook 50. The hook 50 has an integral depending hook shaft 51 journaled in a wall 52 integral with the bed 1. At its lower end, beneath the wall 52, the hook shaft 51 has a crank arm 53 connected by a link 54 to one arm 55 of a bell crank lever, pivotally mounted intermediate its ends on the wall 52 and having a second arm 56 which is connected by a pitman 57 to the crank 29. Thus, oscillation is imparted to the hook 50 upon rotation of the crank 29. The mechanics are such that one cycle of oscillation is imparted to the hook 50 upon each rotation of the main shaft 7.

The hook 50 is generally cup-shaped and comprises a ring 58 that is arcuate in cross section and carried by an arm 59 extending from the lower edge of the ring and radially relatively to the hook shaft 51. The arm 59 in effect defines the bottom of the ring 58 which is open except for the arm 59. The ring 58 is also open at the top and has an inwardly directed flange 60 that terminates in a free edge 61 which is circular and is disposed concentrically of the axis of the hook shaft 51. The flange 60 is continuous except for a gap formed by a slot 62 cut through the flange 60 from the free edge 61 into the ring 58, the slot 62 being inclined relatively to a radius from the axis of the hook shaft 51 to define a loop seizing beak 63 internally of the hook 50.

The needle 41 descends inside and closely adjacent to the flange 60 and is thus disposed adjacent to the 1 path of travel of the loop seizing beak 63. The mechanism is designed so that as the needle 41 rises, it will throw a loop of thread into the path of travel of the loop seizing beak. The width of the slot 62 and the inclination of it relatively to the axis of the hook is designed to produce a gap in the ring that, at its opening in the flange, is wide enough angularly of the ring 58 to accommodate the needle thread loop, or in other words, the width of the gap is determined by the clearance required to permit loop formation. To accommodate movement of the needle 41 laterally of the line of feed during ornamental stitching, the pivot axis of the needle bar gate 45, which is defined by the pivot rod 46, is aligned with the axis of the hook shaft 51 so that upon lateral movement of the needle 41, its deposition radially of the hook 50 will not change and it will also be in operative relation relatively to the path of travel of the loop seizing beak 63. At the same time, the hook 50 is located in front of the needle 41 and feed dog 34 so that it is readily accessible by means of a slide plate 64, for example, for the purpose of changing the bobbin.

A thread carrier, or specifically, a bobbin carrier 65 is mounted internally of the hook 50 in a manner to provide for oscillation of the ring 53 relatively thereto and for passage of the needle thread loop around the same. The bobbin carrier is formed with an annular Wall 66 that defines a recess or Well for receiving a thread carrying bobbin 67, the wall 66 having an inwardly directed flange 68 at its lowerend upon which the bobbin 67 rests. To facilitate removal of the bobbin, there is provided a finger notch 69. Extending from approximately the mid-point endwise or vertically of the wall 66 and substantially normal thereto is an outwardly directed flange 70. To support the bobbin carrier 65 inthe ring 58, there is provided cooperating bearing surfaces between them. With reference to FIGS. 9, and 11, there is a peripheral groove 71 formed in the flange 70 and designed to receive the'flange 60 of the ring 58, the flange 60 constituting a bearing rib for supporting the bobbin carrier 65. The groove 71 is defined by an upper bearing surface 72 that bears against the upper surface of the flange 60, a lower bearing surface 73'that bears against the lower surface of the flange 60, and a peripheral bearing surface 74 that is formed on a radius com-' plemental to the radius of the free edge 61 of the flange 60 and is in bearing engagement with the free edge 61.

Above the upper bearing surface 72, the flange 70 has an arcuate free edge 75 that is generally concentric with the ring 58 and terminates over the flange 60 at a point spaced from the free edge 61 thereof. The needle thread loop slides along the edge 75 as it is expanded and thrown about the bobbin carrier by the loop seizing beak 63. Beneath the lower bearing surface 73, the flange 70 has a free edge 76 that is also concentric with the ring 58 and for clearance is spaced inwardly from the inner surface of the ring 58. The upper limb of the needle thread loop passes over the flange 70 and wall 66 and the lower limb thereof passes beneath the flange 70 and wall 66. The flange 70 is appropriately beveled as at 77 and there are provided beveled surfaces as at 78 and 79 to facilitate the smooth passage of the needle thread limbs about the bobbin carrier 65.

At its end opposite from the point of loop seizure, the flange 70 has an inclined flat surface 80 that provides clearance for the thread loop and is designed to receive the loop as it slides off the beak 63 at cast-off. Adjacent to the surface 80, the flange 70 terminates in an abutment surface 81. At its end adjacent to the point of loop seizure, the flange 70 is formed with a notch 82 that is bounded at one side by a thread controlling finger 83 and atthe other side by an edge including a loop detaining shoulder 84 and an abutment face 85. On the periphery of the Wall 66, there is a bobbin thread tension spring 86 secured by a fastening screw 87 and an adjusting screw 88. The free end of the spring 86 has a tab 89 that is received within a hole 90 in the wall 66. A thread eye 91 through which the bobbin thread B emerges is formed in the wall 66 under and adjacent to the free end of the spring 86, a threading slot 92 being provided to facilitate threading the eye 91.

The bobbin carrier 65 is generally semi-circular in shape with an arcuate edge defined by the peripheral hearing surface 74 and a diametrical edge 93 defined by the abutment surface 81, the adjacent edge of the wall 66, and the edge of the thread controlling finger 83. Thus, when in operative position, the bobbin carrier 65 is disposed eccentrically within the ring 58 with the peripheral bearing surface'74 against the free edge 61 and the diametrical edge 93 disposed substantially diametrically of the ring 58. To hold the bobbin carrier 65 in its operative position and to prevent turning of it with the ring 58, there is a bracket 94 (FIG. 7) mounted on a flange 95 on the top of a bushing 96 in which the hook shaft 51 is journaled. For securing the bracket 94 on the flange 95, there is a groove 97 formed in the top of the flange 96 that receives a rib 98 on the bottom of the bracket, and a screw 99 extends through a bore in the bracket and is threaded into the flange 95. The advantage of this construction is that, with the hook shaft 51 journaled in a bore in the bushing 96, it is a simple matter from a manufacturing standpoint to form accurately the groove 97 and the bore for the screw 99 in the flange 95 since the hook shaft bore is avail-able for gauging. Thus, when assembled, the parts are automatically and accurately aligned relatively to the hook 50.

The bracket 94 has an upstanding arm 100that is adjacent to the point of loop seizure and spaced from the free edge 61 of the flange 60 to provide clearance for the needle 41. The arm 100 terminates beneath the flange 70 except for an upstanding lug 101 that extends into the notch 82 and cooperates with the abutment face 85 to prevent rotation of the bobbin carrier 65 in one direction.

The bracket 94 has a second upstanding arm 102 that carries a platform 103 having a substantially straight face 104 opposed to the diametrical edge 93 of thebobbin carrier 65, an outer edge 105 that conforms to the curvature of the ring 58 and is spaced from the free edge 61 thereof to provide for turning of the ring 58, and an arm 106 ex tending beyond the face 104. On top of the platform 103,

there is mounted an abutment member 197 formed of spring metal and pivotally secured at its rearward end to the platform 103 by a pivot screw 108. The forward end of the abutment member 107 is positioned laterally of the platform 103 by a washer 169 of conventional configuration, i.e., a circular planar element having a central aperture to reduce the same to an annular shape. The washer 109 is received within a bore 110 in the abutment member and secured to the platform 103 by a screw 111.

The abutment member 107 has a downwardly bent arm 112 that is disposed between the face 104 and the bobbin carrier 65 and serves as a thread guard. The arm 112 has a free end 113 that engages the abutment surface 81 to prevent turning of the bobbin carrier 65 in the direction opposite to the direction in which the lug 101 is operative.

The abutment member 167 is adapted to be lifted oi the washer 199 and swun about the pivot screw 198 to move the free end 113 away from the bobbin carrier 65 and thus permit removal of the bobbin carrier 65 from the ring 58. When swung out, the free end 113 is adapted to rest on the arm 106. To return the abutment member 167 to its operative position, it is swung about the pivot screw 103 until it snaps over the washer 1519.

Formed on the flange 5 of the bushing is an upstanding arm 114 carrying a needle guard 115 which is formed with a needle uarding surface 116 that positions the needle relatively to the path of travel of the loop seizing beak 63 and keeps the needle from being deflected into the path of travel of the loop seizing beak 63 and thus being struck by the beak.

The bushing 96 must, of course, be positioned accurately angularly since its position determines the positioning of the needle guard 115 and the racket 94. To accomplish this, the screw 99 has an unthreaded end 117 that is received within a bore 118 in the wall 52. When positioned, the bushing 96 is then locked by a nut 11). The advantage of this construction is that the single screw 99, not only secures the bracket 94 to the flange 95, but also positions them and the needle guard 115 angularly relatively to the needle 41, thereby producing an economical construction and one that is easy to assemble, particularly since it does not require any aligning. A further advantage which is obtained by forming the needle guard 115 integral with the bushing 6 is that there results a construction that is easy to manufacture. The critical dimension in the location of the needle guard 115 is in positioning it relatively to the path of travel of the loop seizing beak 63, which is about the axis of the hook shaft 51. Since the hook shaft is journaled in the bushing 96 which thus determines the axis of it, and the needle guard 115 is formed as an integral part of the bushing, in the same manner as with the groove 97 and bore for the screw 99, the needle guard 115 can be gauged relatively to the hook shaft bore in the bushing 96 and it is therefore a relatively simple matter to hold the necessary manufacturing tolerances.

The specific formation of the needle guard, which is illustrated particularly in 516. 8, is designed to provide more efficient loop formation. Upon lateral displacement of the needle 41 during ornamental stitching, the needle can be made to descend at any selected point within the designed range between a left position and right position, which are designated L and R in FIG. 8. The center of this pattern is indicated at C. In each position, the stroke of the needle is the same and it will descend past the path of travel of the beak 63, indicated by the line L1, a fixed amount, or in other words, upon each stitching cycle, the eye of the needle, which is designated 120, at the point of maximum penetration of the needle, is on a line L2 that is parallel to the path of travel L1 of the beak 63. From the line L2, the needle begins to rise and, in the usual manner, to throw a loop of needle thread that is to be seized by the beak 63. A predetermined rise of the needle 41 will provide an optimum loop of thread and will position the eye 120 of the needle an optimum distance below the path L1 of the loop seizing beak 63, to insure efficient loop seizure. In any one position of the needle laterally of the line of feed, this can be obtained by timing of the machine. However, in a zigzag machine, the position of the needle 41 laterally of the line of feed, varies and the rise of the needle 41 before loop seizure also varies by the distance that the needle rises during the time required for the beak 63 to travel from loop seizing position with the needle in the right position R to the loop seizing position with the needle in the left position L.

The above variation in the position of Le needle 1-1 at loop seizure is exaggerated in an oscillating hook machine because the hook makes only one complete cycle of oscillation upon each reciprocation of the needle bar, and because loop seizure occurs after the hook comes to a stop and begins turning in the forward direction, i.e., at the beginning of the forward movement of the beak 63. The beak 63 is therefore moving relatively slowly. Thus, a considerable amount of time is required for the beak 63 to pass from the right to the left loop seizing position, and the needle 41 rises a considerable distance during this time.

The optimum position of the eye 128 of the needle 41 at loop seizure is represented in FIG. 8 by the line L3. The selection of the optimum condition is limited, for example, by the fact that the eye 12% must be below the line L1 at loop seizure. Also, any position to the right of the position producing the desired optimum produces a loop that is smaller than the optimum and any position to the left thereof produces a loop that is larger than the optimum. A loop that is too small increases the possibility of skipped stitches while a loop that is too large increases the possibility of fouling of the thread.

The actual position of the eye of the needle at loop seizure varies alon a line L4. By timing the machine, the actual position of the eye 121) at loop seizure at any selected position between the left and right positions L and R, which occurs at the intersection of the lines L3 and L4, can be made to coincide with the optimum. This position is usually selected as the center C but in the pres sent machine is made to occur between the center position C and the right position R. Thus, the size of the loop at the right position R is enlarged relatively to the normal condition, to reduce the possibility of skipped stitches, without unduly enlarging the size of the loop at the center position C and thereby causing fouling. This, of course, results in a considerable enlargement of the loop at the left position L but which can be accommodated by controlling the loop, as hereinafter explained.

Turning now to the requirements of the needle guard 115, the needle guarding surface 116 must be concentric with the path of travel of the beak 63 and a predetermined distance inside the path of travel of the beak 63 in order to keep the needle 41 from being struck by the beak 63 and to position it in loop seizing relation to the beak 63. The needle guard is provided with an inclined surface 121 at its upper edge adjacent to the needle guarding surface 116, which is designed to perform two functions, first, it is a needle deflecting surface to prevent needle breakage by keeping the needle from descending on top of the guard, and second, it provides clearance for formation of the thread loop.

It is, of course, obvious that if the needle guard 115 is to function in a manner to hold the needle out of the path of the beak es, some portion of the needle guarding surface 116 must be opposite the point of the needle at loop seizure. A point P is selected on the needle and represents the point that is as close to the end of the needle as possible and which must be opposite the needle guarding surface 116 at loop seizure in order to obtain a needle guarding function. Plotting this point in FIG. 8, there is produced an inclined line L5 that is parallel and spaced below the line L4. The line L5 represents the optimum line of intersection between the needle guarding surface 115 and the inclined surface 121.

To form the inclined surface 121 on the top edge of the needle guard 115 and intersecting the cylindrical needle guarding surface 116 along the line L would be very diflicult and expensive. In accordance with this invention, the inclined surface 121 is formed cylindrically by a circular peripheral cutter arranged on an axis at the required inclination to the needle guarding surface 116. The diameter of the cutter is selected to produce a line of intersection L6 between the two surfaces that approximates the line L5. The resulting diameter of the cutter produces an inclined surface 121 having the desired characteristics and which is very simple and economical to make. 7 V

Returning now to the loop controlling function of the needle guard 115, as above pointed out there is an excessively large loop formed by the needle when in the left position L, which is likely to cause fouling. One important characteristic of the present needle guard 115 is that when the needle is in the left position L, the eye 120 at the point of maximum penetration, at the line L2, is considerably below the line L6 and is thus against the needle guarding surface 116. Thus, as seen in FIGS. 2l23, as the needle 41 rises, it cannot throw a loop on the loop seizing side thereof. As the thread wipes against the needle guarding surface 116, a certain amount of the thread is forced through the eye 120 of the needle, thus reducing the amount of thread on the loop seizing side. It is only after the eye 120 rises above the line L6 that loop formation can proceed unhindered.

In FIGS. 13-16, there is illustrated various positions in stitch formation with the present hook. FIGS. 13 and 14 show the condition at loop seizure. The beak 63 of the hook is advancing and has just entered the loop of the needle thread N. The slot 62 is bounded by

side edges

122 and 123 and terminates in a throat 124. The edge 122 forms a part of the beak 63 while the edge 123 is spaced therefrom to define a gap in the free edge 61 of the flange 60 to provide for loop formation. Upon continued turningof the hook after the beak 63 has entered the loop, the needle thread N slides back along the edge 122 into the throat 124, which expands the loop and carries the upper limb thereof outwardly over the free edge 75 of the flange 70 on the bobbin carrier 65. As the hook continues to turn, this upper limb of the needle thread slides along the edge 75 and over the top of the bobbin carrier 65. The under limb of the needle thread N engages the loop detaining shoulder 84, and as the hook continues to turn, slides across the under face of the bobbin carrier 65.

FIG. 15 illustrates the parts at cast-off. At this point, the loop of needle thread N is pulled by the take-up mechanism which is of the link type and includes a takeup arm 125 connected at one end to the needle bar crank 42 and connected at an intermediate point to an anchor link 126 pivotally mounted in the frame. The take-up lever pulls the thread N out of the throat 124, along the edge 122, and onto the surface 80. The inclination of the edge 122 is designed to provide a smooth surface for the thread loop to slide onto the surface 8 0.

Shortly after the position of FIG. 15, the direction of turning of the hook reverses and it begins its return stroke. In FIG. 16, the parts are illustrated with the hook in its return stroke, and shortly before stitch setting; The needle thread N has now been fully concatenated with the bobbin thread B.

For strength andrigidity, the arm 59 is made as wide as possible consistent with obtaining an adequate mounting surface for the bracket 94 and adequate clearance between the arm 59 and the bracket 94 at the extreme positions of the hook.

Numerous'alterations of the structure herein disclosed Will suggest themselves to those skilled in the art. 'However, it is to be understood that the-present disclosure relates to a preferred embodiment of my invention which .is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.

Having thus described the nature of the invention, what I claim herein is:

1. In a sewing machine having a frame, a bushing mounted in said frame and having at one end a flange, a loop taker having a shaft journaled in said bushing and having a ring disposed adjacent to said flange, said ring being formed with a loop seizing beak defining a path of travel upon angular movement of said ring about the axis of said shaft and having a loop seizing position in said path wherein said beak is adapted to enter a needle thread loop, an element disposed adjacent to the path of travel of said loop seizing beak and having a predetermined operative position relatively to the path of travel of said loop seizing beak both radially of and angularly about the axis of said shaft and relatively to said loop seizing position, said element being carried by said flange, means for positioning said bushing angularly in said frame, and means for securing said bushing in angularly adjusted position. I

2. In a sewing machine having a frame, a bushing mounted in said frame and having at one end a flange, a loop taker having a shaft journaled in said bushing and having a ring disposed adjacent to said flange, said ring being formed with a loop seizing beak defining a path of travel upon angular movement of said ring about the axi of said shaft, a needle guard having a predetermined operative position relatively to the path of travel of said loop seizing beak both radially of and angularly about the axis of said shaft, said needle guard being carried by said flange, means for positioning said bushing angularly in said frame, and means for securing said bushing in angularly adjusted position.

3. In a sewing machine having a frame, a bushing mounted in said frame and having at one end a flange, a loop taker having a shaft journaled in said bushing and having a ring disposed adjacent to said flange, said ring being formed with a loop seizing beak defining a path of travel upon angular movement of said ring about the axis of said shaft and having a loop seizing position in said path wherein said beak is adapted to enter a needle thread loop, an element disposed adjacent to the path of travel of said loop seizing beak and having a predetermined operative position relatively to the path of travel of said loop seizing beak both radially of and angularly about the axis of said shaft and relatively to said loop seizing position, said element being carried by said flange, said frame having a hole, a screw secured in said flange and having a free end extending into said hole for positioning said bushing angularly in said frame, and means for securing said bushing in angularly adjusted position.

4. In a sewing machine having a frame, a bushing mounted in said frame and having at one end a flange, a loop taker having a shaft journaled in said bushing and having a ring disposed adjacent to said flange, said ring being formed with a loop seizing beak defining a path of travel upon angular movement of said ring about the axis of said shaft, a needle guard integral with said flange and having a predetermined operative position relatively to the path of travel of said loop seizing beak both radially of and angularly about the axis of said shaft, means for positioning said bushing angularly in said frame, and means for securing said bushing in angularly adjusted position.

5. In a sewing machine having a frame, a bushing mounted in said frame and having at one end a flange, an oscillating loop disposed adjacent to said flange, and having a shaft journaled in said bushing, a thread carrier disposed internally of said loop taker, cooperating hearing surfaces on said loop taker and said thread carrier for supporting said thread carrier and providing for angular movement of said loop taker relatively to said thread carrier, means for holding said thread carrier against turning with said loop taker and including a bracket, means for mounting said bracket on said flange, a needle guard on said flange, and means for positioning said bushing angularly in said frame and thereby locate said bracket and said needle guard relatively to said loop taker.

6. In a sewing machine in accordance with claim 5, in which said means for mounting said bracket on said flange and said means for positioning said bushing angularly in said frame comprises a screw extending through said bracket and threaded into said flange, said frame having a bore aligned axially with said screw when said flange is in operative position, and an end on said screw extending into said bore.

7. In a sewing machine having a frame, a needle mounted in said frame for endwise reciprocation to define a needle path and formed with a thread eye having a predetermined position at maximum penetration of said needle from which position said needle rises to form a thread loop, a loop taker for cooperating with said needle in the formation of stitches, said loop taker being journaled in said bed for angular movement and having a loop seizing beak defining a path of travel passing closely adjacent to the needle path and at a predetermined distance above said thread eye at loop seizure, and a stationary needle guard mounted in said frame and having a needle guarding surface for holding said needle out of the path of travel of said loop seizing beak at loop seizure, an inclined surface on said needle guard for directing said needle toward said needle guarding surface and for providing clearance for formation of a needle thread loop, said inclined surface intersecting said needle guarding surface below the path of travel of said loop seizing beak a distance adequate for loop formation and above said thread ey at the point of maximum penetration for preventing loop formation until said needle rises to lift said thread eye above the needle guarding surface.

8. In a sewing machine having a frame, a needle mounted in said frame for endwise reciprocation to define a needle path and for lateral vibration to vary the lateral position of the needle path and thereby define an ornamental stitch pattern, a vertical axis oscillating loop taker for cooperating with said needle in the formation of stitches, said loop taker being mounted in said frame and formed with a loop seizing beak having a path of travel passing closely adjacent to the needle path in the lateral positions of said needle for seizing a thread loop, and a stationary needle guard mounted in said frame and having a cylindrical needle guarding surface concentric with and spaced inwardly of the path of travel of said loop seizing beak relatively to the axis of said loop taker, and an inclined surface intersecting said needle guarding surface along a line substantially parallel to a line defined by a point on said needle at loop seizure in the various lateral positions of said needle.

9. In a sewing machine in accordance with claim 8, in which said inclined surface is cylindrical and is formed about an axis inclined to the axis of said needle guarding surface.

10. In a sewing machine having a frame including a bed, feeding mechanism defining a line of feed across said bed, a needle mounted in said frame for endwise reciprocation to define a needle path and for vibration laterally of the line of feed to vary the lateral position of the needle and thereby define an ornamental stitch pattern, a vertical axis oscillating loop taker mounted in said bed with the axis of said loop taker disposed in front of said needle in a vertical plane parallel to the line of feed and including said needle in one position of lateral vibration thereof, said loop taker cooperating with said needle in the formation of stitches and formed with a loop seizing beak having a path of travel passing closely adjacent to the needle path in the various lateral positions of the needle for seizing a thread loop, and a stationary needle guard mounted in said frame and having a needle guarding surface parallel to the needle path in the various lateral positions of the needle and disposed on the loop seizing side of said needle, and an inclined surface on the top of said needle guard and intersecting said needle guarding surface for directing the needle to said needle guarding surface and for providing clearance for formation of a needle thread loop on the loop seizing side of said needle.

11. In a sewing machine having a frame including a bed, feeding mechanism defining a line of feed across said bed, a needle mounted in said frame for endwise reciprotion to define a needle path and for vibration laterally of the line of feed to vary the lateral position of the needle and thereby define an ornamental stitch pattern, a bushing in said frame and having a flange, a vertical axis oscillating loop taker for cooperating with said needle in the formation of stitches and having a shaft journaled in said bushing and a loop seizing beak having a path of travel passing closely adjacent to the needle path in the various lateral positions of the needle for seizing a thread loop, and a stationary thread guide formed integral with said flange and having a needle guarding surface parallel to the needle path in the various lateral positions of the needle, and an inclined surface on the top of said needle guard and intersecting said needle guarding surface for directing the needle to said needle guarding surface and for providing clearance for formation of a needle thread loop.

References Cited in the file of this patent UNITED STATES PATENTS 657,400 Diamond et a1. Sept. 4, 1900 2,019,284 Wesson Oct. 29, 1935 2,148,385 Waterman Feb. 21, 1939 2,883,953 Johnson Apr. 28, 1959