US3541983A - Stitching machine needle guide improvements - Google Patents

Description

United States Patent inventor George P. Diacont Richmond, Virginia Appl. No. 766,043

Filed Oct. 9, 1968 Patented Nov. 24, 1970 Assignee American Machine & Foundry Company a corporation of New Jersey STITCIIING MACHINE NEEDLE GUIDE IMPROVEMENTS 6 Claims, 6 Drawing Figs.

U.S. Cl 112/227 Int. Cl. D0511 55/06 Field of Search 1 12/170, 171,172, 227, 94, 35, 37, 38, 50,176,177,178

References Cited UNITED STATES PATENTS Re. 7,986 12/1877 Crosby 112/170 603,100 4/1898 Bellefeuille 112/227 2,618,232 11/1952 112/176 2,699,131 [/1955 112/176 3,081,719 3/1963 Fake 112/37 FOREIGN PATENTS 470,678 6/1914 France 112/227 Primary Examiner-H. Hampton Hunter AttorneyGeorge W. Price and Walter Lewis ABSTRACT: A top needle guide support is provided for a curved needle which is passed through a formed node of work material. The top support has portions which separate the thread strands and portions for the thread strands to turn and run on. It also has a removable stitch control block having a bottom cavity. The bottom cavity cooperates with a plunger to control the work material node formed therebetween.

Patented Nov. 24, 1970 3,541,983

Sheet 3 of 3 INVI'JN'I'OR.

GEORGE R DIACONT ATTORNEY 1 STITCIIING MACHINE NEEDLE GUIDE IMPROVEMENTS This invention relates tostitching machine needle guide improvements, and more, particularly, to improvements in the forth between the two chucks during stitching, The rear one of said chucks passes the needle through a node or hump of the material or work to be stitched and into the front chuck. The

front chuck receives the needle from the rear chuck and continues to move the curved needle through the work until it. passes entirely therethrough. After this, the front chuck backs up slightly to slacken the near and far loops or stands of thread extending from the work tothe needle eye. Thereafter, the chuck and needle mechanism or head is raised slightly to clear the needle of the work so that it can be transferred back from the front-to the rear chuck in readiness tomake the next stitch; Before the needle is transferred back to the rear chuck a looper engages 'and enlarges the near loop strand of thread and transfers it to a thread puller. The thread puller pulls the loose end of the thread entirely through the work. In other words, the stitching simulates hand stitching in that a threaded needle is first passed entirely through the work, then the loose FIG. 1 is a broken away side elevation view of the Hinckle stitching machine'huving my.-inventive features incorporated therein. the parts of the machine being shown in the positions end of the thread is drawn entirely through the work,.and

thereafter the threaded needle is returned to proper position near the work for the next stitch. Of course, in hand stitching the thread is pulled entirely through the work by simultaneously moving the. needle clear away from the work. In the stitching machine the equivalent is accomplished by holding the needle stationary in the front chuck after it has cleared the work and pulling just theloose thread'and clear through and away from the work by the looperand thread puller. Otherwise, the sequence of operations is the same as in hand stitching and gives asimilar end product in terms of looks and quality. In the above described machine a needle guide is provided to assist in correct travel of the curved needle from the rear chuck through the node ofmaterial and into front chuck.

One of the objectives of machine operations as contrasted to hand operationsis to increase output without an increase in costs or sacrifice in quality, and one of the-problem's encounand pulling, the direction of thread travel is abruptly changed and sharp and sudden forces or loads are imposed on the thread which may cause it to break.

Briefly, in my invention I provide a novel combination top needle support and thread separator and Guide structure they have at the start ofa stitch;

FIG. 2 is -a view similar to that of FIG. 1 showing the posi tion of the parts after the threaded needle has passed entirely through the work;

FIG. 3 is a' partial top plan view of the mechanism shown in FIGS. 1 and 2;

FIG. 4 is a partial right side view of the mechanism shown in FIG. 3;

FIG. 5 is an exploded perspective view of the assembled mechanism of FIGS. 3 and 4; and

' FIG. 6 is a bottom view ofthe stitch control block.

In the instant patent application. only those portions of the Hinckle machine will be described as are necessary for a clear understanding of my improvements therein. For an additional description ofthe Hincklemachine the reader may refer to the copendingHinckle U.S. Pat. application Ser. No. 666.035.

Referring now to my patent application drawings. the Hinckle machine has a rear needle chuck I0 and a front needle chuck 11 which are mounted for oscillation about a horizontal axis 12. A curved needle 13 having an eye 13 is transferred back and forth between the chucks I0 and 11. In FIG. 1 the needle 13 is being carried by the rear chuck 10 through a formed node or hump 14 of work 15. The work or material 15, which comprises two layers which are to be blind fell stitched together, is positioned between a fixed top presser plate 16 and a bottom movable presser plate 17. The node 14 is formed bya plunger or anvil 18 which is raised atthe right moment through a not shown opening in the bottom presser plate 17 against the work 15.

The needle eye l3 has a single strand of'thread extending therethrough. Its far end 19 extends from the eye 13' to the previously formed stitch in the work,'and its 'near end 20 is the loose or trailing end of the thread, see FIG. 1. After the needle passes into chuck 11, the needle is released by chuck 10 and carried by chuck 11 to the FIG. 2 position wherein the needle which reduces needle and thread breakage at high speeds.

This structure cooperates with the mentioned needle guide of the Hinckle .disclosure in a manner to be described hereinafter. In addition, in my invention l ingeniously incorv has passed entirely through the work. In this position the thread end 19 is now a far loop 19 and the forward part of thread end 20 is now a near loop 20, both loops extending through the material and tov the needle eye 13' where of course they terminate at each other since they are all part of the same single piece of short thread which is used in the machine.

The upper presser plate 16 is generally square, see FIG. 3, and has one of itsdiagonal axes aligned parallel to the axis 12. At one endit has a notch 21 formed therein and the direction of material feed is designated by arrow 22. The upper presser plate 16 is part of the mentioned Hinckle needle guide, or to be more accurate, the needle guide is integrally formedon the top surface of upper presser plate 16; It comprises a generally U-shaped slug of metal 23 with its opening 24'embracing a central hole 25 formed in. plate 16 and into which notch 21 opens. The opposite ends of the legs of the U-shaped slug or mass of metal 23 have left and right hand grooves 26 and 27 formed therein. These grooves 26 and 27 are aligned with each other along a line which is perpendicular to the chuck oscillation axis 12. The grooves have opposite side walls 26'.

26" and 27', 27". Their bottom surfaces and side walls provide bottom and lateral support and guidance for the curved needle which is moved through the material along an are 28. see FIG. 5.

In my invention I provide top support and guide means for the curved needle. The top needle support and guide means is are aligned along an are similar to the curvature of needle 13. They are positioned slightly away from the bottoms of the grooves 27 and to define needle guide and support chan nels 34 and 35 respectively which are aligned along the are 28 and are essentially closed except at their opposite ends so that the needle 13 is at all times properly guided and supported in its travel from left ro. right, seeFlGS. v1 and 2. Thus, the needle will not be laterally deflected from its intended line of travel. ln approaching the material hump 14 its nose or point is guided by rear channel 35 and in leaving the material hump 14- its trailing end is guided by front channel 34.'Theres almost no likelihood for the needle to miss its mark" or to accidentally strike some unintended part or be deflected and broken.

The front blade 32 also performs the function of separating the far and nearthread loops l9 and 20', see FIG. 2, wherein the far loop 19 is located behind blade 32 and the near loop 20' in front of blade 32. When needle 13 moves through material 15 left to right its eye 13' ends up in is elevated position. Since the needle rides along the bottom edges of the blades 32 and 33, when the eye 13' is elevated the strands l9 and of FIG. 1 are automatically separated by front blade 32 into the loops 19"and 20' ofFlG. 2.

The front blade 32 is connected to the central portion by tapered sloped or beveled surfaces for the thread to turn or run on to eliminate thread breakage due to sharp pulls or changes of thread direction. For instance, and viewing FIG. 4, the blade 32 is connected on its left side with the central portion 30 by tapered sloped or beveled surfaces 36, 37 and at its right side to thecentral portion 30 and overlying flange 31 by tapered sloped or beveled surfaces 38-41 inclusive. Surfaces 36, 37 are important during the thread looping and pulling sequence mentioned heretofore. Briefly, in this sequence of operation, a not shown looper arm swings from the right to the left. It grasps or hooks on to the near loop 20' to enlarge it and transfer it to a not shown thread puller that continues the operation of drawing the trailing end of the thread entirely through the work material. The looper transfers thenear loop 20 from the right side of the machine to its left side and at a location that is elevated with respect to the position of near loop 20' in FIG. 2. This entails a sudden pull and change of direction, and surfaces 36, 37 reduce thread breakage by providing reduced wear thread turning and running surfaces.

The surfaces 36-39 are also important in progressing from the FIG; 1 to the FlG. 2 position since as is clearly evident therefrom the thread has to turn or run from a direction that is first essentially horizontal to one that is finally elevated at an angle ofabout 45, and in making this transition there is a constant load or pull on the thread. Since each short thread used in the sewing of one garment goes through the same stitching,

' looping, and thread pulling sequence many times before the garment is finished, it will readily be understood that it is essential to reduce wear on the thread if the output of the machine is to be increased without thread breakage. Thread breakage makes for a sloppy stitch and also represents down time of the machine which really is a reduction in its output. The latter is also true of needle breakage, which of course also represents an increase in costs due to needle replacement.

The surfaces 40, 41 are actually cutouts to provide clearance for a not shown tension finger. ln actual operation of the machine after needle 13 is carried by chuck 11 clear through the node 14 the chuck 11 backs up slightly to'slacken the loops 19' and 20 slightly. The tension finger for which the clearance cutouts 40, 41 are provided assists in keeping the loop 19 to the rear so that it can be grasped and held by a not shown gripper to prevent the pull by the looper on loop 20' from being transmitted back into the stitch to cause puckering. The gripper is not part of the instant invention and is described and claimed in simultaneously filed US. Pat. application Ser. No. 766,044 for Stitching Machine improvements by James C. Mills, Jr., which is assigned to the same assignee as the instant application.

Referring to FIG. 5, the central portion 30 of the top needle guide and support means 29 has a bottom slot 42 formed therein. Thisslot 42 is adapted to receive a stitch control and adjustment block 43 therein. The block 43 is retained in slot 42 by a screw 44 which extends into aligned threaded holes 45 and 46 formed in the tops of parts 30 and 43. However, it is only removably retained therein so that other blocks similar to block 43 but having slightly different characteristics can be inserted therein to give-different desired stitch characteristics. in actual practice the block 43 is only about one-half the size represented in FIG. 5.. Therefore, adjustability is provided by changing only a minute part of the total apparatus. When viewed from the left of H0. 5 it will be seen that the bottom side edges of block 43 are provided with transverse convex shaped grooves 47. When viewed from thefront, see FIGS. 4 and 5, the bottom front and rear edges of block 43 are provided with a pair of spaced rounded nibs 48 spaced by a notch 49. The notches 49 are aligned with the blades 32 and 33 and the nibs 48 are positioned along opposite sides of the needle 13 when it is traveling through the guide channels 35, 34. These parts 48, 49 are for the purpose of further guiding and supporting the needle 13.

Referring also to FIG. 6, it will be seen that the elements 47, 48, 49 surround a cavity 43' in the bottom of block 43. The size and shape of cavity 43' determines the type of "bite" the needle 13 takes in the node 14. That is to say, it, in cooperation with the plunger or anvil 18 is a feed mechanism for the material to be stitched which controls the type of node 14 formed which in turn determines the length and depth of the stitch in the material. The plunger 18 has a notch 18' formed in its tip which is aligned with the are 28. It is raised at the proper moment by mechanism described in the Hinckle patent application to push the material 15 into cavity 43 to form the node 14. The .needle 13 then travels through the material along the are 28 by following the path of elements channel 35,

' notch 49, slot '18, notch 49, and channel 34.

lf one wants to adjust the width or length of the stitch, or the bite that the curved needle takes in the. material, it is only necessary to replacethe block 43 with another suitable one merely by loosening the screw 44. It will be appreciated that the quality of a finished stitch is also determined by the ability of the machine to always from the same kind of node for each successive bite of the needle. in my invention the block 43 does this by providing a backing or back up for the node formed about the anvil 18. The cavity 43, in combination with the block parts such as 47, 48 ensure that the same kind of node 14 is always formed. By virtue ofthe removable stitch control block 43 in the slot 42 the feature of controlling the stitch pattern is uniquely built into the top needle support and guide 29. Element 29 of course is also an element which serves as a thread separator, a thread wear reducer, and also a thread and needle breakage reducer. Block 43 controls the pattern of the stitch also in terms of its uniform quality. In the Hinckle machine a top support for the node or hump of work material 14 was lacking. In my invention the stitch control block 43 provides such top support so that the same kind of node is always formed by the anvil or plunger 18 with a given stitch control block 43.

The combination needle support guide and stitch control 29, 43 is supported off a bracket 50. The outer extremity of bracket 50 is received in a guideway 51 formed in flange 31. The part 29 is locked in its in or out adjusted position on bracket 50 by a screw 52 passing through a hole 53 formed in a clamp plate 54 into and alined threaded hole 55 in flange 31. The position of the assembly 29, 43 is also adjustable right or left by virtue of an adjustable mounting for the inner end of bracket 50. This is illustrated by clamping screws 56 disposed in a slot 57 of bracket 50, see FIG. 3.

The bracket 50 is supported off a portion 58 of a not shown hanger for the chuck assembly or sewing head 10, ll, l2, 13. As described in the Hinckle patent application the hanger is what raises and lowers the sewing head at the correct time in sequence with the other parts of the machine. Before the needie 13 is transferred back from chuck 11 to chuck the anvil .18 is lowered and the sewing head is raised. When the sewing head is raised the top needle guide 29 and its stitch control block 43 are raised therewith so that it is not in the way of reverse travel of needle 13 from chuck 11 to chuck l0. Addi- 'tionally, however, since parts 29, 43 are raised with the sewing head they cooperate in guiding the needle 13 back from chuck 11 to chuck l0.

While there has been shown and described a particular embodiment of the invention, it will be obvious to those skilled in and scope ofthe invention. lclaim:

1. In a stitching machine having a threaded curved needle, a bottom needle support memberhaving a curved slot formed therein, said needle traveling along said curved slot, a top needle support member in combination therewith, said top member having a blade disposed in said slot and spaced from the bottom thereof todefine a needle guide and support channel therebetween for said needle, said channel being closed by said top and bottom members and being open at its opposite ends for passageofsaid needle therethrough, an opening formed in said bottom member for forming a node of work material in said. bottom member along the path of travel of said'needle through said slot, said opening dividing said slot portion overlyingsaid. curved needle and being disposed in front of said node'wbereby as said needle progresses through said node said blade front portion is operative to retain said two thread strands spaced from each other-along opposite sides of said blade front portion.

3. In a stitching machine as in claim 2, thread wear reducer means on said top member, said thread wear reducer means comprising beveled surfaces formed on said top member along opposite sides of said blade front portion for said spaced thread strand to turn and run on, said beveled surfaces being disposed between said blade front portion and said node.

4. In a stitching machine as in claim 1, means for backing up said node, said node backing means comprising a backing member mounted in said top member above said bottom member opening, said backing member having a bottom cavity formed therein which is disposed transverse to said slot and is adapted to receive said node, and said cavity having a predetermined size and shape to control the bite of the needle in said work material.

5. In a stitching machine as in claim 4, means for adjusting the bite of said needleinsaid work material. said adjusting means comprising a slot'in said top member, and a removable mounting for saidbacking member in said slot whereby. different node backing members may be readily mounted in said top member.

6. in a stitching machine as in claim 3, a stitch control block removably mounted in said top member above said bottom member opening for backing up said node of work material, said block having a bottom cavity formed therein, said'cavity and bottom opening being aligned with each other and'an underlying plungensaid plunger being adapted to be advanced toward said aligned bottom opening and cavity to feed some work material therein to form said node, and said cavity having-a predetermined size-and shape to determine the bite of said needle in said'work material.

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