US3688711A

US3688711A - Machines stitch forming and thread controlling mechanisms for sewing

Info

Publication number: US3688711A
Application number: US35450A
Authority: US
Inventors: Henryk Szostak; Clarence C Smith
Original assignee: Union Special Machine Co
Current assignee: Union Special Machine Co
Priority date: 1970-05-07
Filing date: 1970-05-07
Publication date: 1972-09-05
Anticipated expiration: 1989-09-05
Also published as: DE2122191A1; SE379065B; GB1343645A; SE405740B; FR2091320A5; CH547378A; JPS5248857B1; SE7414583L; CA930249A

Abstract

The machine embodying the mechanism is of low silhouette frame construction so that it reduces the weight of the machine and the space required for its use. The means for operating the needle carrier is an oscillating arm which serves to shift the needle carrier back and forth along a straight line. One end of said arm is positioned in a slideway in said needle carrier so as to be free for both rotational and translational movement relative thereto. Provision has been made for adequate lubrication of the relatively sliding surfaces, to minimize the development of high temperatures in the course of high speed sewing operations.

Description

United States Patent Szostak et al.

[ Sept. 5, 1972 [72] Inventors: Henryk Szostak, Oak Park; Clarence C. Smith, Chicago, both of Ill.

[7 3] Assignee: Union Special Machine Company,

. Chicago, Ill.

[22] Filed: May 7, 1970 [21] Appl. No.: 35,450

2,977,910 4/1961 Covert .Q ..ll2/256 FOREIGN PATENTS OR APPLICATIONS 572,116 l/l958 Italy ..ll2/221 Primary ExaminerJarnes R. Boler AttorneyJohn A. Howson [57] ABSTRACT The machine embodying the mechanism is of low silhouette frame construction so that it reduces the weight of the machine and the space required for its use. The means for operating the needle carrier is an oscillating arm which serves to shift the needle carrier back and forth along a straight line. One end of said am is positioned in a slideway in said needle carrier so as to be free for both rotational and translational movement relative thereto. Provision has been made for adequate lubrication of the relatively sliding surfaces, to minimize the development of high temperatures in the course of high speed sewing operations.

15 Claims, 11 Drawing Figures mmmszv 51912 I 3,688,711 I suit a nr 5 I PAIENTEHsEP 5' m2;

SHEET 3 BF 5 FIG.3.

rmminsrr f 3.688.711 Y SHEET 5 [IF-5 7 MACHINES STITCH FORMING AND THREAD CONTROLLING MECHANISMS FOR SEWING This invention relates to industrial sewing machines, which are of a character that require high speed operation in order to provide for a satisfactory output of goods from the machine.

An important feature of the invention is the provi- 7 been found to do harm to the fibers of the fabric pieces sion of an overall construction which is of such operations are the production of an overedge seam, or

the production of a line of stitching inwardly from the edge of a work piece, or the production of a combination of the two foregoing lines of stitching to provide what is generally known as a safety stitch.

Another feature of the invention is the provision of a very compact overall construction which reduces the amount of space required in a factory for the installation of a number of such machines. This aspect of the invention, moreover, serves to reduce to a minimum the tendency of high speed operation of a sewing machine to produce objectionable vibrations and noise.

Toward the foregoing end, the invention has been developed in relation to long established machines of the overedge seaming type. Machines of that character are normally provided with a single curved needle with which other stitch forming members cooperate both above and below the surface along which the work pieces are advanced in the course of a seaming operation. Certain aspects of the invention are highly desirable in relation to such machines, but in addition the invention is adapted to provide sewing machines of the types mentioned above, namely for producing merely a through and through line of stitching, or the production of a line of safety stitches which incorporate overedge stitching and through and through stitching in slightly spaced relation to each other.

An important feature of the invention is the provision of a straight needle or a pair of straight needles adapted for reciprocation along a straight line in the course of a stitching operation. While certain of the features and advantages of the invention may be utilized in connection with a machine in which the needle or needles will be reciprocated along a line at an angle to the plane along which the work piece is being advanced in the course of a stitching operation, a further important feature of the invention isits adaptability for use in connection with a machine in which the needle or'needles will be reciprocated in a straight line extending in a vertical direction or at least perpendicular to the plane along which the work'being stitched is advanced.

An important advantage of the invention, which is derived to the greatest extent by a machine in which the needle or needles will be reciprocated along a line perpendicular to the path of movement of a workpiece through the stitching zone is the formation of the desired stitches with minimum injury to the'material being stitched. In this connection, it has been found that sewing machines as heretofore constructed have being stitched, particularly when these fabrics are of a heavy gauge and are produced from synthetic plastic yarns. For example, the friction generated by the needle in its passage through such a fabric has been found to generate a relatively high temperature which in some instances does serious damage to the synthetic resin fibers.

Another aspect of the invention is the light weight construction of the needle-carrying member. This tends to reduce to a minimum the force required and the vibration that may be produced in the course of reciprocating the needle or needles at high speed. In connection with this aspect of the invention, the latter incorporates special lubricating means which reduce to a minimum the friction created by the high speed reciprocation of a needle-carrying member along the surface of a guide rod or the like which controls the path of movement of the needle carrier.

A further feature of the invention is the provision of thread control mechanism which is adapted to pull off thread from a thread supply at a desired rate and to impart take-up actions to the thread in the course of a stitching operation.

While, as above stated, the present invention has I been found to be very helpful and efficient in connection with low silhouette machines, and more particularly to overedge machines, certain advantages are derived from features of the invention in relation to other types of machines.

With the foregoing objects, features and advantages of the invention in mind, an illustrative embodiment of the same will now be described in some detail in relation to the accompanying drawings in which:

FIG. 1 is a front view, partly in elevation and partly in vertical section through a portion of a machine embodying the invention;

FIG. 2 is an elevational view of the machine taken from the left side of FIG. I;

FIG. 3 is a vertical sectional view through the machine taken along the line 3-3 of FIG. 1;

FIG. 4 is a horizontal sectional view through the left hand portion of the machine shown in FIG. I, with certain parts in cross section and other parts in plan;

FIG. 5 is a detailed view, partly in section, showing the needle-carrying and guide members of the machine, with certain partsshown in section;

FIG. 6 is a detail view partly in elevation and partly in vertical section showing certain parts of the thread control means;

FIG. 7 is a detail view largely in elevation but partly in section, showing the needle-carrying means;

FIG. 8 is a detail view, partly in elevation and partly in section, showing a portion of 'the frame and certain thread handling elements of the machine;

FIG. 9 is adetail view showing the presser foot provided in the machine and a part of its supporting means;

FIG. .10 is a detail view in perspective showing certain elementsof the thread control mechanism of the machine; and

.FIG. 11 is a plan view of the guide rod for the needle carrieras seen from the top of FIG. 7.

Theembodiment of the invention illustrated in the drawings is in connection with a high speed sewing machine of the general character disclosed in the US. Pat. to Hayes No. 3,101,686 granted Aug. 27, 1963. As shown in the instant drawings it embodies a quite low frame structure for housing most of the operating mechanism of the machine. This housing 10, as best indicated in FIGS. 1, 2 and 4 has a main section 1 1 which encloses much of the operating mechanism of the machine. This housing has a bottom plate 12 applied thereto for retaining a quantity of lubricant in the base portion of the frame to ensure proper lubrication of most of the relatively moving parts of the machine which have some frictional engagement. A section 13, which is shown as a separate element of the frame structure, assists in providing an open space within the frame of the machine for receiving various operating parts, and this section of the frame has an extension 130 (FIG. 1), which carries a spring retaining housing 13b which, in a well known manner, carries a spring for urging a presser bar downwardly to retain work pieces against a work supporting surface 11a that extends horizontally along a plane about midway of the overall height of the machine. The top of the frame is provided with a closure section 14 which is preferably removably attached to the top portion 13 of the frame so as to normally enclose the main housing portion of the frame but permits access when necessary to the interior of the housing.

Suitably journalled within the frame 11 in a manner more fully disclosed in the above-mentioned Hayes patent is a main drive shaft 15. It will be understood that this shaft, which is broken away at its right end in FIG. 1, extends outwardly beyond a vertical wall provided at the right hand side of the housing, and this shaft is journalled within suitable bearings carried by the housing. The outer end of the shaft, not shown, which extends outwardly from the housing, has secured thereto a conventional pulley and hand wheel by which the main drive shaft may be rotated. As is usual, a suitable belt connection is provided from an electric motor and clutch unit fornormally rotating the main drive shaft at a comparatively high speed when the clutch is closed under manual or automatic control.

As has been indicated in the foregoing, the illustrative machine embodying the present invention is provided with a suitable needle carrier which is arranged to carry one or more straight needles that are reciprocated by appropriate movement of the carrier. The construction illustrated for this purpose involves a relatively light frame member 16 which has two cylindrical bearing portions 16a and 16b which surround a cylindrical guide member 17. This guide member is retained in a fixed position, preferably in a vertical direction as shown in FIGS. 1, 2 and 5. As will be explained, suitable arrangements have been made for ensuring proper lubrication of the outer surface of the guide member 17 so as to facilitate free sliding movement of the needle carrier 16 up and down along the outer surface of the guide member. As best shown in FIGS. 7 and 11 the guide member 17 has an enlarged head portion 17a disposed eccentrically in relation to the body portion 17b along which the needle carrier is reciprocated in a vertical direction. The enlarged head 17a fits into a suitable opening within the frame extension 130. By turning the head 17a slightly in one direction or the other the position of the body portion 17b which performs the guiding function may be adjusted to position the needles in desired relation to the work being stitched and to the cooperating stitch forming elements. When adjusted into the desired position, the guide member 17 may be locked in such position by one or more set screws 17 c.

Extending downwardly within the guide member 17 is a passage which carries a lubricant conducting wick member 17d. This extends downwardly through substantially the full length of the guide member, which is preferably sealed off at the lower end by a screw plug 17e.

For delivering lubricant to the head portion 17a of the guide member there is provided another wick member 17f which has an end portion that rests upon the upper end of the wick 17d. Wick 17f extends laterally outwardly from the head 17a of the guide member and is passed through a longitudinal opening within the extension 13a of the frame. From the right end of the latter, as shown in FIGS. 1 and 5, the wick extends downwardly into the interior of the body portion 11 of the frame. As will be understood from the disclosure of the above-mentioned Hayes patent, there are various devices within the enclosed portion of the frame which are adapted to dip into and create a spray of lubricant, in the course of operation of the machine, and a portion of this lubricant will then be caught by the downwardly extending portion of wick 17f. As shown in FIG. 7, the guide member 17 is provided with radially extending passages 173 which serve to deliver lubricant from the wick 17d to the outer surface of the guide member 17. This is done in the regions in which the two bearing portions 16a and 16b of the needle carrier are shifted upwardly and downwardly along the guide member in the course of operation of the machine. As best shown in FIG. 5, the portion 17a of the guide member is provided with an annular groove which is adapted to receive a sealing member 17h which may be formed of rubber or the like. This guards against the leakage of lubricant from the guide member downwardly around the upper end 17a of the guide member.

Reciprocation of the needle carrier 16 in a vertical direction is accomplished by an arm 18 which is secured to a shaft 19. Suitable connections are provided for rocking the shaft 19 and thereby causing the outer end of the arm 18 to cooperate with the needle carrier 16 in the manner best shown in FIG. 7. Thus the outer end of the arm 18 carries a pin 18a on which is journalled a roller element 18b which cooperates with a U-shaped surface 16e of the needle carrier 16. This surface of the carrier permits a slight sliding movement of the roller 18b, toward the right and toward the left in FIG. 7, as the arm 18 is rocked through a suitable angle to impart the desired reciprocatory movements to the two needles. Rocking movements are imparted to the arm 18 by well known connections from the main drive shaft of the machine to the shaft 19 on which the arm 18 is secured. These connections are of the character disclosed in the above mentioned Hayes patent. Briefly they comprise a pitman 20 having an enlarged portion 20a at its lower end (FIG. 3) which carries a needle bearing 20b that cooperates with a crank portion 15a of the main drive shaft. As will be apparent, the rotation of the drive shaft will bring about reciprocation and oscillation of the pitman 20, which is permitted by the relatively large opening 20d in the pitman which surrounds another rock shaft 19d which operates the upper trimmer knife of the edge trimming mechanism which may be of the type disclosed in the patent to Hayes. At its upper end, the pitman 20 carries a pin 200 by which the pitman is pivotally connected with an arm 21 secured to the rock shaft 19. In this manner oscillatory movements are imparted to the arm 18 to bring about vertical reciprocation of the needle carrier 16. The lower portion of the needle carrier 16 is provided with needle retaining portions 16c and 16d adapted to receive the upper ends of two

needles

22 and 23. Needle 22, which carries the thread used in producing an overedge line of stitching, is retained in the bore of portion 16c bymeans of a set screw 16f. Similarly the needle 23, which participates in the production of a through and through line of stitching of the 401 type (often called a chain stitch or a double locked stitch), is retained with its upper end in the bore of portion 16d by means of a set screw 16g. As shown in FIGS. 2 and 4, thread 24 is supplied to the needle 22, from a suitable source to be described, while thread 25 is supplied to the needle 23.

In the illustrated machine there is provided mechanism adapted to produce a three thread overedge line of stitching and a two thread line of chain stitching, so that the final result will be the formation of what is generally designated a safety stitch. Considering the overedge needle 22, there is arranged to cooperate with this an overedge looper 26 and an under looper 27, FIG. 1. The looper 26 is secured to a rod 28 which is adapted for longitudinal reciprocatory movements and also oscillatory movements. The reciprocatory movements are imparted thereto by an arm 29 which is rockable about a rod or shaft 30. The arm 29 has connected therewith an arm 31 that cooperates, through a ball pin, with a pitman 32. The opposite end of the pitman 32 cooperates with an eccentric on the drive shaft which thus imparts rocking movements to the

arms

31 and 29. The lower end of arm 29 has spaced apart rounded portions 290 which cooperate with disks 18a and 18b carried by the shaft 28. Accordingly rocking of the arm 29 will impart longitudinal movements to the shaft 28. Oscillatory movements are imparted to said shaft by the cooperation of a block 280, FIG. 4, with a cam groove 28d provided in a sleeve 28e which surrounds the shaft. Thus upon each revolution of the main drive shaft the looper carrying shaft 28 will be reciprocated back and forth and will be oscillated to impart the desired movement to the overedge looper 26.

Looper 27 is carried by a rod 33 which is arranged for reciprocation in a bearing sleeve 34. The upper end of the rod 33, as shown at the right in FIG. 1, is connected by a link 35 with an arm 36 connected with a sleeve arranged for rocking movement about a shaft 37. Such rocking movement is imparted to the arm 36 by an arm 38 which is connected with the same sleeve as the arm 36 and has its outer end connected by a pitman 39 with a crank element 40 secured to the main drive shaft 15. In this manner, reciprocatory movements are imparted to the under looper 27 in timed relation to the movements of the overedge looper 26 and the reciprocatory movements of the needle 22.

Needle 23 is shown as being adapted to cooperate with a looper 41 which is secured to a shaft 42 that is arranged for longitudinal, reciprocatory movements and also to oscillatory movements. The reciprocatory movements are imparted through the action of an oscillatory arm 43, the upper rounded end of which cooperates with disks 42a carried by the shaft 42 adjacent its right end. Arm 43 is arranged for rocking movement along with an arm 43a, extending at substantially right angles to the arm 43, for rocking movement about a shaft 44. The free end of the arm 43a'is of spherical form and cooperates with the lower end of a pitman 45 (FIG. 1) whose opposite end cooperates with a spherical portion of a crank 46 carried by the main drive shaft 15. In this way the desired movements are imparted to the looper 41 to bring about the production of a line of chain stitches, of the 401 type, in cooperation with the needle 23.

The threads supplied to the various loopers mentioned above are shown at various points in their path of movement in FIGS. 2 and 4. Those going to the

loopers

26 and 27 for the production of the overedge line of stitching are designated 24a and 24b, respectively, while that going to the looper 41 for the production of the 401 type of chain stitching is designated 25a.

The means for handling the various threads, to direct the same to the appropriate stitch forming member and to apply a pull-off and take-up action thereto will now be described. As best shown in FIGS. 2 and 4, there is suitably mounted in appropriate relation to the sewing machine a bracket 50 having an upstanding portion 50a in the region adjacent to the sewing machine frame. In the illustrative apparatus, the bracket 50 is provided with five thread tensioning devices 51. These are of the type that involve a pair of flat disks 51 which are adapted to receive the thread between them and apply a frictional resistance. to the movement of the thread between them. Each of the five thread tensioning means comprises a base element 52 on which the lowermost disk 51'a rests, the base 52 being supported by the bracket 50. A screw threaded member 53 has an enlarged head at its upper end and a shank 53a which has threads at its lower end meshing with internal threads in the block 52. A spring 54 surrounding the stern 53a has its upper end acting against the under surface of the head of the screw and its lower end resting upon the uppermost disk 51b. The spring thus serves to urge the disk downwardly against the other tension disk. By varying the distance of the head of the screw 53 above the block 52, the amount of force applied by the spring 54 to the upper disk 51b may be varied, so that the tension applied to the thread passing between the two disks 51 may be adjusted.

The thread 24 delivered to the machine from a spool, not shown, which may be carried by a suitable stand, not shown, is passed between the disks 51' which form the right hand group in FIG. 4. After passing between these disks the thread is delivered, through an opening in the upstanding portion 50a of the bracket, to and through an opening 55a (FIG. 1) in a plate 55 suitably secured to the frame of the machine. From this plate the thread is passed downwardly, as shown in FIGS. 2, 4 and 6, to and through openings provided in the arms of a U-shaped bracket 56, and from the latter the thread is passed to an opening in a plate 57 carried by the needle carrier 16. From here the thread is passed downwardly to and through the eye of the needle 22. In its passage between the openings in the arms of the bracket 56 the thread is engaged by extension 19b of member 19a, upon clockwise rocking of the latter about the axis of rock shaft 19.

In a somewhat similar manner the thread 25 is passed from the cooperating disks 51' through another opening in the upward extension 500 of the bracket 50 and then downwardly to a bracket 58 secured to the frame of the machine. This bracket is provided with two laterally spaced portions which have upwardly extending portions 580 provided with openings through which the thread 25 is passed for cooperation with a rock member 59. As will be seen from FIG. 2, the rocking of the upper portion of member 59 toward the right will impart a pulling action to the thread 25. From the extension 58a, which is spaced from that shown in FIG. 2, the thread is passed upwardly and toward the right (FIG. 2) to and through an opening 55b (FIG. 1) in the plate 55. From this point the thread extends over to an adjustable bracket 60 having an opening therein adjacent its upper end, through which the thread 25 is passed. Then the thread extends to and through an opening in an arm 61 which is secured by screws 61 a (FIG. 5) to one face of the arm 18 which, as described above, serves to cause the vertical reciprocation of the needle carrier 16. From the opening in the arm 61 the thread 25 extends downwardly to and through an opening in a member 16h which is secured to carrier 16, and from here to another opening in the plate 57 and then through the eyelet of needle 23, as shown in FIGS. 1 and 2.

The thread for the upper looper 26 of the overedge stitch forming mechanism is designated 24a. As shown in FIG. 4 it is delivered to the thread tensioning disks 51' carried by the bracket 50 and is discharged therefrom through an opening in the vertical portion 500 of the bracket. As shown in FIG. 2, this thread is delivered downwardly from the bracket 50 to the outer ends of a guide member 63 which is secured by a screw 64 to a bracket carried by the frame of the machine. Member 63 has two laterally spaced

arms

63a and 63b, as shown in FIG. 10, these being arranged at opposite sides of the path of movement of the member 59. As will be seen from FIG. the rocking movement of the member 59 will serve to impart a take-up action to the thread 240 as the member is shifted from the full line position shown in FIG. 2 to the broken line position shown in said figure. From the arm 63b the thread 24a is delivered directly to the overedge or upper looper 26. As will be understood, the looper 26 serves to carry the thread 24a toward the needle 22 where this thread will be combined with the thread 24 in the course of a stitch forming operation.

Thread 24b is delivered from a suitable source, not shown, to the centrally disposed disks 51', FIG. 4, and from the latter through an opening in the vertical portion 50a of the bracket 50, and from this down to openings at the outer ends of members 65a and 65b of bracket 65 which is secured by a screw 66 to a part 62 of the frame of the machine. From the arm 65a the thread 24b is delivered to the lower looper 27 of the overedge stitch forming mechanism. As is best shown in FIG. 10, the portion of the thread 24b extending between the arms 65a and 65b of the bracket 65 will be engaged by the lower portion of the rock member 59, as the latter swings toward the left in FIGS. 2 and 10, and thus will have a take-up action imparted thereto.

The thread 25a for the looper 41, which thread is united by said looper with the thread 25 from needle 23, is delivered between a pair of thread tensioning disks 51 carried by the bracket 50, then through an opening in the vertical portion 50a of the bracket and from this downwardly to the region of a take-up cam 67 secured to the drive shaft 15, as shown in FIG. 8. From here the thread 25a is passed to an eyelet 41a adjacent the lower end of the looper 41, from which it extends outwardly and then'lengthwise of the active portion of looper 41, as best shown in FIG. 1. In the region of the take-up cam 67, the thread 25a is passed between a cast-off plate 67a and a support plate 67b. These plates are slotted to permit passage of the cam therethrough. Plate 67a is secured to support plate 67b by a pair of screws 67c. The thread 25a is guided across the slot of the plate 67 a by guide wires 67d which are disposed at opposite sides of plate 670 (FIG. 1).

It will be clear from the foregoing that all of the threads used in the formation of the safety stitch, including three threads used in the formation of the overedge stitch and two for a line of chain stitches, will be guided along appropriate paths from suitable sources to the stitch forming elements, with provisions along their path of movement form imparting an appropriate take-up action and pull-off action thereto, to ensure proper stitch formation.

The foregoing is believed to disclose quite fully the novel features of the present invention as applied to an illustrative type of sewing machine. It will be understood that the machine includes other mechanism of a generally known character, such as work feeding mechanism, to enable it to perform the desired stitching operations. The work feeding mechanism, as shown in FIG. 2, involves a feed bar 68 which carries a feed dog 68a. There may also be provided a differential feed dog 68b mounted on another feed bar 68c. The feed dogs are given their four-motion movements by conventional connections from the main drive shaft 15, as partially shown in FIG. 2. As shown in FIG. 9, a presser bar 69, having a reduced, cylindrical end portion 69a, has clamped to the latter a presser foot carrying member 69b. To the lower end of the latter there is pivotally connected a presser foot 690 arranged to be spring urged downwardly against the work support by a spring within the housing 13b. Also changes may be made in the nature and construction of various features and parts of the machine, within the scope of the appended claims. While the invention has been disclosed in relation to a safety stitch sewing machine, certain aspects of the invention may be used in connection with machines adapted to produce other types of stitching.

What is claimed is:

l. A stitch forming mechanism for use in a sewing machine including a needle-carrying member, a guide member on which said needle-carrying member is slidably mounted and a drive mechanism for reciprocating said needle-carrying member on said guide member, characterized by a rocker arm which is driven'by and rigidly mounted between its ends on an oscillatable rock shaft and connected at one end with the needlencarrying member in a mounting comprising a slideway formed in the needle-carrying member and a bearing mounted on said one end of the rocker arm, said arm thereby being positioned in the slideway for rotational and translational movement therein to reciprocate the needle-carrying member on theguide member.

2. A stitch forming mechanism according to claim 1, in which there is a needle in said needle-carrying member and means arranged to cooperate with said needle being adapted to carry a loop of thread from a point below a work piece being stitched to a point above said work piece for the reception of the needle on its next movement toward and through the work piece to form an overedge line of stitching.

3. In a sewing machine as set forth in claim 2, said needle carrying member having a second straight needle adapted to carry thread through a work piece, and means cooperating with said second needle for producing a line of stitching in said work piece spaced from said overedge line of stitching.

4. In a sewing machine as set forth in claim 3, said means cooperating with the first mentionedneedle to form an overedge stitch comprising a pair of reciprocatory thread carrying members, one of said reciprocatory thread carrying members being arranged to carry a loop of thread through a loop of thread created by the first mentioned needle, and the other of said-reciprocatory members being arranged to carry a loop of thread through the loop of thread carried by the first mentioned looper and to present its loop of thread in the path of said needle.

5. A stitch forming mechanism according to claim 1, characterized in that the needle-carrying member incorporates a bifurcated portion having two spaced apart branches forming the slideway for the rocker arm bearing and each of said branches is also slidably mounted on the guide member.

6. A stitch forming mechanism according to claim 5, characterized in that the end of the rocker arm includes a pin mounted at right angles thereto and the bearing is mounted coaxially on the pin.

7. A sewing machine having a frame providing a. work supporting surface and a stitch forming mechanism comprising a needle-carrying member, a guide member on which said needle-carrying member is slidably mounted and a drive mechanism for reciprocating said needle-carrying member on said guide member, characterized by a rocker arm which is driven by and rigidly mounted between its ends on an oscillatable rock shaft and connected at one end with the needle-carrying member in a mounting comprising a slideway formed in the needle-carrying member and a bearing mounted on said one end of the rocker arm, said end thereby being positioned in the slideway for rotational and translational movement therein to reciprocate the needle-carrying member on the guide member, said guide member having an eccentrically disposed head portion by which it is mounted in the frame.

8. A sewing machine having a frame providing a work supporting surface and a stitch forming mechanism comprising a needle-carrying member, a guide member on which said needle-carrying member run is slidably mounted and a drive mechanism for reciprocating said needle-carrying member on said guide member characterized by a rocker arm which adjacent one end is driven byand rigidly mounted on an oscillatable rock shaft and connected at its other end with the needle-carrying member in a mounting in which the said other end of the arm, is both rotatable and movable in translation, with respect to said needlecarrying member, said guide member having an excentrically disposed head portion by which it is mounted in the frame, said machine having two needles in spaced relation to each other carried by said needle carrying member and means cooperating with each of said needles to fon'n two lines of stitching in a work piece operated on by said machine and said guide member is movable by rotating its eccentrically disposed head portion to vary the position of the needles and their needle-carrying member.

9. A sewing machine as set forth in claim 8 in which means are provided for firmly retaining the guide rod in the position into which it has been turned.

10. A sewing machine having a frame providing a work supporting surface and a stitch forming mechanism comprising a needle-carrying member, a guide member on which said needle-carrying member is slidably mounted and a drive mechanism for reciprocating said needle-carrying member on said guide member characterized by a rocker arm which adjacent one end is driven by and rigidly mounted on an oscillatable rock shaft and connected at its other end with the needle-carrying member in a mounting in which the said other end of the arm, is both rotatable and movable in translation, with respect to said needlecarrying member, said guide member having an eccentrically disposed head portion by which it is mounted in the frame, and in which said guide member has a passage therein extending downwardly from said head portion, a lubricated wick in said passage at least one opening in said guide member extending from its outer surface to said passage intermediate the ends of said member, to deliver lubrication to the reciprocation of said needled-carrying member on said guide member.

11. A sewing machine as set forth in claim 10 in which there is a source of lubricant in said sewing machine and a second wick positioned to receive lubricant from said source and having a portion in engagement with said first mentioned wick for transferring lubricant to it.

12. A sewing machine having a frame providing a work supporting surface and a stitch forming mechanism comprising a needle-carrying member, a guide member on which said needle-carrying member is slidably mounted and a drive mechanism for reciprocating said needle-carrying member on said guide member characterized by a rocker arm which adjacent one end is driven by and rigidly mounted on an oscillatable rock shaft and connected at its other end with the needle-carrying member in a mounting in which the said other end of the arm, is both rotatable and movable in translation, with respect to said needlecarrying member, said guide member having an eccentrically disposed head portion by which it is mounted in the frame, and said head portion of said guide member is rotatably mounted in the frame and there are means for rotating said portion to adjust the postion of the needle-carrying member with respect to the frame.

13. In a sewing machine adapted to produce an overedge seam'and an inwardly spaced line of chain stitches, stitch forming means adapted to produce said seam and said chain, thread controlling means for guiding and applying pull-off and take-up actions to threads involved in said stitching operations which comprises: a main drive shaft, a rock shaft, connections from said drive shaft to said rock shaft for imparting rocking movements to the latter, a rod having a portion intermediate the ends thereof secured to said rock shaft for oscillation thereby, means for guiding threads delivered from supply sources to said stitch forming means, said thread guiding means involving spaced eyelets between which sections of various threads are passed, said rod having portions above and below the axis of said rock shaft adapted to engage said sections of the threads and apply a take-up action thereto, whereby lengths of the various threads required in the stitch forming operations are pulled from theirsources of supply and are taken-up to complete the formation of a stitch in the ing a pulling action to the thread for the other of said needles.

l5. ln a sewing machine as set forth in claim 14, a cam secured to the main drive shaft adapted to engage the thread being delivered to the looper which cooperates with one of the needles to produce a chain stitch, said cam being arranged to impart take-up and pull-off actions to said thread.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,688,711 Q DATED September 5, 1972 INVENTOR(S) Szostak et a1.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown beiow:

In the Specification:

Col. 5, lines 44 & 45, "disks 18a and 18b" should be

disks

28a and 28b respectively.

Q Col. 6, line 36 "disks 51" should be disks 5i In the Claims:

Col. 9, line 2, delete needlencarrying" and substitute needle-carrying Col. 10, line 43, change "needled" to needle O Col. 12, line 11, after "carried" insert by Signed and Sealcd this thirt Day of January 1976 [SEAL] Attest:

' RUTH c. MASON c. MARSHALL DANN Arresting Officer Commissioner ofPatenrs and Trademarks

Claims

1. A stitch forming mechanism for use in a sewing machine including a needle-carrying member, a guide member on which said needle-carrying member is slidably mounted and a drive mechanism for reciprocating said needle-carrying member on said guide member, characterized by a rocker arm which is driven by and rigidly mounted between its ends on an oscillatable rock shaft and connected at one end with the needle-carrying member in a mounting comprising a slideway formed in the needle-carrying member and a bearing mounted on said one end of the rocker arm, said arm thereby being positioned in the slideway for rotational and translational movement therein to reciprocate the needlecarrying member on the guide member.

4. In a sewing machine as set forth in claim 3, said means cooperating with the first mentioned needle to form an overedge stitch comprising a pair of reciprocatory thread carrying members, one of said reciprocatory thread carrying members being arranged to carry a loop of thread through a loop of thread created by the first mentioned needle, and the other of said reciprocatory members being arranged to carry a loop of thread through the loop of thread carried by the first mentioned looper and to present its loop of thread in the path of said needle.

7. A sewing machine having a frame providing a work supporting surface and a stitch forming mechanism comprising a needle-carrying member, a guide member on which said needle-carrying member is slidably mounted and a drive mechanism for reciprocating said needle-carrying member on said guide member, characterized by a rocker arm which is driven by and rigidly mounted between its ends on an oscillatable rock shaft and connected at one end with the needle-carrying member in a mounting comprising a slideway formed in the needle-carrying member and a bearing mounted on said one end of the rocker arm, said end thereby being positioned in the slideway for rotational and translational movement therein to reciprocate the needle-carrying member on the guide member, said guide member having an eccentrically disposed head portion by which it is mounted in the frame.

8. A sewing machine having a frame providing a work supporting surface and a stitch forming mechanism comprising a needle-carrying member, a guide member on which said needle-carrying member is slidably mounted and a driVe mechanism for reciprocating said needle-carrying member on said guide member characterized by a rocker arm which adjacent one end is driven by and rigidly mounted on an oscillatable rock shaft and connected at its other end with the needle-carrying member in a mounting in which the said other end of the arm, is both rotatable and movable in translation, with respect to said needle-carrying member, said guide member having an excentrically disposed head portion by which it is mounted in the frame, said machine having two needles in spaced relation to each other carried by said needle carrying member and means cooperating with each of said needles to form two lines of stitching in a work piece operated on by said machine and said guide member is movable by rotating its eccentrically disposed head portion to vary the position of the needles and their needle-carrying member.

10. A sewing machine having a frame providing a work supporting surface and a stitch forming mechanism comprising a needle-carrying member, a guide member on which said needle-carrying member is slidably mounted and a drive mechanism for reciprocating said needle-carrying member on said guide member characterized by a rocker arm which adjacent one end is driven by and rigidly mounted on an oscillatable rock shaft and connected at its other end with the needle-carrying member in a mounting in which the said other end of the arm, is both rotatable and movable in translation, with respect to said needle-carrying member, said guide member having an eccentrically disposed head portion by which it is mounted in the frame, and in which said guide member has a passage therein extending downwardly from said head portion, a lubricated wick in said passage at least one opening in said guide member extending from its outer surface to said passage intermediate the ends of said member, to deliver lubrication to the reciprocation of said needled-carrying member on said guide member.

12. A sewing machine having a frame providing a work supporting surface and a stitch forming mechanism comprising a needle-carrying member, a guide member on which said needle-carrying member is slidably mounted and a drive mechanism for reciprocating said needle-carrying member on said guide member characterized by a rocker arm which adjacent one end is driven by and rigidly mounted on an oscillatable rock shaft and connected at its other end with the needle-carrying member in a mounting in which the said other end of the arm, is both rotatable and movable in translation, with respect to said needle-carrying member, said guide member having an eccentrically disposed head portion by which it is mounted in the frame, and said head portion of said guide member is rotatably mounted in the frame and there are means for rotating said portion to adjust the postion of the needle-carrying member with respect to the frame.

13. In a sewing machine adapted to produce an overedge seam and an inwardly spaced line of chain stitches, stitch forming means adapted to produce said seam and said chain, thread controlling means for guiding and applying pull-off and take-up actions to threads involved in said stitching operations which comprises: a main drive shaft, a rock shaft, connections from said drive shaft to said rock shaft for imparting rocking movements to the latter, a rod having a portion intermediate the ends thereof secured to said rock shaft for oscillation thereby, means for guiding threads delivered from supply sources to said stitch forming means, said thread guiding means involving spaced eyelets between which sections oF various threads are passed, said rod having portions above and below the axis of said rock shaft adapted to engage said sections of the threads and apply a take-up action thereto, whereby lengths of the various threads required in the stitch forming operations are pulled from their sources of supply and are taken-up to complete the formation of a stitch in the stitch forming region of the machine.

14. In a sewing machine as set forth in claim 13, said means for producing an overedge seam involving a reciprocatory needle, an overedge looper and an under looper, and said means for producing said line of chain stitches involving a reciprocatory needle and a cooperating looper, said thread controlling and guiding means being so constructed and arranged that said rod engages and applies a pulling force to threads being delivered to one of said needles and two of said loopers, and a rock member carried said rock shaft for imparting a pulling action to the thread for the other of said needles.

15. In a sewing machine as set forth in claim 14, a cam secured to the main drive shaft adapted to engage the thread being delivered to the looper which cooperates with one of the needles to produce a chain stitch, said cam being arranged to impart take-up and pull-off actions to said thread.