DE6604644U - FABRIC FEED DEVICE FOR SEWING MACHINES - Google Patents

Description

RA.316 060 * 19.6 65

OR.-ING. DIPL.-ING. M SC.

HÖGER - LEGAL RIGHTS - GRIESSBACH

PATENT LAWYERS IN STUTTGART

A 34 509 m

m - 125

June 15, 1965

Union Special Machine Company Ohio ago / 111., USA

Stoffvorecliubeinriohtimg for Sewing machines.

The invention relates to a fabric _{feed device for sewing machines 9} in which the feed movement of a fabric fan can be adjusted in terms of size and direction by means of a radially displaceable eccentric member rotating with a drive shaft and an inclined guide.

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In particular, it has the present invention with a mechanism to easily control the fabric feed on a sewing machine, which of the adjustment of the stitch length and serves to generate a forward and backward feed of the cow goods relative to a stitch-forming device, with the control is carried out in a simple manner by the operator of the machine. Certain Features of the Invention are also particularly advantageous when using the sewing machine in conjunction with other punctures to be performed by the machine, with parts in particular according to the invention are provided which must be moved back and forth in order to "oscillate with variable amplitude, as is e.g. during the swinging movement of the needle bar on a zigzag » Sewing machine which is pail.

Constructions have already been proposed which allow the operator of a sewing machine to feed to be controlled according to size and direction. Me known However, constructions are not with regard to a quick and reliable reversal of the feed direction of the sewing material satisfactory, with stitches of the same length either forwards or backwards when the machine is running at high speed reliably cannot be generated. In particular are

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in the known constructions large eccentric parts of considerable Wloht necessary, which rotate with the drive shaft, ao that strong unbalance forces occur and the running * the quietness of the machine is impaired.

The invention is based on the task of remedying the deficiencies outlined and proposing a device

4ie
the tnerkliohejt run calm not impairing force of the masses

appear.

This is achieved according to the invention in that inside the hollow-drilled drive shaft sine by external means eohieblichen sliding rod is arranged in the oblique to the = Drive shaft running sliding surfaces are recessed, and that O radially displaceable eccentric link has two drivers, • which engage in the hollow drive shaft and with their ends rest on the sliding surfaces.

According to the invention, an extremely reliable and perfect « freely adjustable mechanism both for varying the stitch = - length as well as to reverse the direction of provision. The advantages of the invention come primarily to the fore on high-speed step-step-ya-huh-aehinen.

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When sewing quilted seams, it has proven to be beneficial to lock the ends of a seam in such a way that the seam is prevented from opening at these ends. to this m reach actual usually careful handling of the sewing rope required at the ends of such a seam by professional manner verses blows the material. The present invention makes special specialist knowledge unnecessary when sewing the seam ends. Ea a simple, easy to control, completely reliable mechanism for reversing the feed direction of the workpiece is proposed, which can be controlled manually or otherwise by the operator to immediately reverse the direction of feed without the need to turn the material through 180 Turn ° su, or after releasing the pressure caused by a presser foot move the sewing material backwards by hand su.

It is assumed that the reversal of the feed direction of a sewing part when passing through the stitch-forming zone is already known. The present invention is affirmed however, with the development of a novel, simpler and more reliable mechanism for achieving of the desired result. The invention also relates

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in connection with this on simplified and reliable Means to vary the length of the stem.

According to the invention, the change in the direction of advance through a simple and koiupaste ExoriantüSg -from differentiated Achieved parts that are very reliable in their operation and quickly and easily from one to the other Direction can be shifted.

TJm these conditions in connection with the change in To fill the stitch length and at the same time the feed direction is a rod within the according to the invention hollow drive shaft is provided which in turn carries an eccentric to drive the feed mechanism. The eccentric contains a part that is permanently connected to the rotating drive shaft, as well as another part that controls the feed Drive exeaenter carries, which is displaceable in a direction transverse to the axis of the drive shaft on the fixed with the Wel le connected part is arranged. One part of the eccentric can be displaced by such an amount that Iir Beiner Normal position is the point of maximum radial eccentricity lies off the axis of the drive shaft on one side of the same, but through the rod by such an amount that point can be moved to the maximum

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Eccentricity is displaced diametrically with respect to the noraial position. This fiährt so., THe the feed dog place when he moved the Mhgut during its movement sur operator acquired through ₉ from the operator, as he usually does. The invention also provides means for the adjustable change of the normal position of the rod within the V-cell in order to thereby vary the amount or the size of the eccentricity of the eccentric. In this case, the eccentric can also be held in a concentric position with respect to the axis of the drive shaft in the best position of the rod, so that no gate thrust effect occurs.

In a preferred embodiment of the invention is a adjustable dial rotatably attached to the housing of the machine, namely next to the upper end of the vertical stand part on the machine side facing the operator. This Skalonscheibo can easily be accessed by the operator person untor use of a pointer or opening can be set to any desired position, the dial being the position to which the feed

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To reverse the Yorsehubrailung by the operator there is an actuating lever on the shaft that carries the -Ska lens ehe ibe attached, which extends along the front of the standing housing annes extends «Me arrangement is dslsei so, uaB regardless of which © Stishläsge is ZasesBenhasg sit the Adjustment of the slsala is established, the operating lever is moved the same distance, in each case the same, to generate the stitch length set on the dial when the feed rate is reversed. This is according to the invention by a "special connection" of the operating lever with which the Ezsen- = trisity of the exaentera sliding rod that changes by 180 ° each time achieved within ^ the driving force. The connection is there made so that regardless of whether the machine is set to 5 or 10 stitches per inch or any other number of stitches per unit of length is set, pivoting the actuating lever controls the Utukehr of the feed direction in each case so that the set Stalk length is preserved in both directions.

The following description of preferred embodiments of devices according to the invention is used in context with the accompanying drawing for further explanation. Show it

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Fig. 1 is a partially sectioned front view of a Lockstitch sewing machine;

Fig. 2 is a partially sectioned side view

from the left in Pig. I:

Pig. 3 shows a section of the upper housing arm ait the operating lever for reversing the feed rate and the dial for setting the stitch length;

Pig. 4 is a partially sectioned bottom view; Pig. Figure 5 is a cross-section along line 5-5 of Pig.

Pig. 6 a front view of an element 4 stitch

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length adjustment ö !! »direction j

Pig. Figure 7 is a side view of the Pig element. 6;

Pig. 8 shows a further side view of the element au3 Pig. 6 looking from the right;

Pig. 9 is a perspective view of an element of the adjustable excenter j

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Pig. 10 is an exploded view of the adjustable Eccentric with drive connecting rod;

Pig. 11 is a longitudinal section of the adjustable eccentric and the drive shaft;

Pig. Figure 12 is a partly elevational view and partly in cross-section Depicted area in the general area of the cloth valve drive mechanism ;

Pig. Fig. 13 is an elevation of an arm of the stitch length adjuster;

Pig. 14 another part of this device;

Pig. 15 is a side view of the Pig part. 14 with direction from the right;

Pig. 16 is a plan view of a sleeve of the stitch length adjuster;

Pig. 17 on top of it «asleht elma? ia üa? Hui * β aue Pig «16

cugowj-uxxowou uaa carry the VorsenuöuiDKehrhebei <=> the rocking shaft;

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Fig. 18 is a cross section of a pulley, which with the lower end of the arm from Pig. 13 connected is;

Pig. 19 is a side view of a part with its mounting on one located within the drive shaft Pole;

Pig. 20 is a top plan view of the advance dial and one Part of the actuating lever for the speed reversal and

Pig. 21 a pawl from Pig. 20th

On the drawing is an embodiment of the invention shown in connection with a lockstitch sewing machine, as described in U.S. Patents 2,351,976 and 2,977,910 is described. Such a machine has a housing eit a base plate 10, a vertical stand 11 and an overhanging arm 12, which at the left end (Pig. 1) a Head, in which the needle bar and a presser foot bar as well as various other parts, which were patented in the USA by Kr. 2,851,976 are arranged. In the overhanging arm 12, a main drive shaft H is in the longitudinal direction

11th

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camps. At the right end of this main drive shaft a handwheel is attached to a pulley 15, via which the shaft is driven by a corresponding connection to an electric motor. A second drive shaft 16 is arranged within the base plate of the housing and extends in the longitudinal direction of the base plate is driven by the main drive shaft 14. This purpose is preferably served by a creamed or corrugated giant 17 , which connects a toothed or shaft wheel 18, which is fastened on the main drive shaft 14, to a corresponding wheel 19 on the drive shaft 16. Furthermore, corresponding compounds in the manner of U.S. Patent 2,851,976 are provided, which up with {over the two drive shafts, the needle moves up and down, a rotating gripper driven and the fabric = · echieber, disposed inside the base plate is to be moved _s .

Since the present invention is primarily directed to the feed mechanism of the machine ₉ , only this will be explained in more detail. The feed mechanism contains a conventional knife feeder (Pig.2) which interacts with a presser foot 21. The presser foot 21 is carried in the usual way by a spring-loaded presser foot bar in the head of the sewing machine. The knife gate valve 20 is on one

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Part 22 attached, which in turn is attached to another part 23 is attached. which of one can be swiveled and aligned movable part 24 is carried. Through the various Teroindungenip over which the knife-gate valve voss rope 24ertrs = gen is, there are options for the corresponding setting of the position of the material slide with respect to the material to be sewn. The part 24 is attached to a hollow shaft 25 which is pivotably mounted in a frame 26 (Pig.12). This frame igt freely pivotable about a fixed axis 27 carried by the base of the machine. The lower part of the right or front end of the part 24 (fig.2) is through A link 28 is connected to an eccentric part 29 (3? ig »1) of the lower drive shaft 16. Through this connection that becomes Part 24 is pivoted about the axis of the shaft 25 and gives the knife feeder at certain times of the movement cycle Machine up and down movements. Laying movements are / the knife valve in and against the Yorschubri-ch ^ rmg durcL a push rod 30 is given, the rear end 30a of which is swingable is mounted around the axis of a hollow Well © 26a, which is from the housing 26 is carried (Pig. 4,10 and 12). The front end of the push rod 30 has a bearing shell 30b, which over a needle roller bearing with a cylindrical port set 31 of the adjustable Eccentric is connected. The cylindrical portsats

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is integral with a slide block 32 and forms an element of the adjustable eccentric. The sliding block has inclined surfaces 32a which, with the inclined surfaces 34a of a part 34 of the adjustable eccentric, form a level guide, the sliding block also encompasses gate jumps 35 with parallel side surfaces 33a which, with the surfaces 34b of the cable 34, form a sliding guide form. The! Part 34 is by means of a Stellsehraube 35 on the drive shaft 16 befestigt.Die 32 Ştei-lung of the slide block relative to the part 34 is determined by slanting the sliding surfaces 36a and 36b _ff which a check in at the inner end? Longitudinally through a bore of the drive shaft 16 extending slide rod 36 adjoin. With the sliding surfaces 36a and 36b, the flat ends of drivers 37 and 38 designed as pins cooperate, which are fastened in part 32 of the eccentric member. The flat ends of the flights are inclined at the same angle as surfaces 36a and 36b. The drivers 37 and 38 are provided in the set position by screws 37a and 38a. The ends of the drivers, together with the sliding surfaces 36a and 36b, form a sliding guide to enable the sliding rod 36 to be displaced in the longitudinal direction within the drive shaft 16 by a limited amount while still holding the toilet 32 of the adjustable eccentric in a very specific position from the portion of the sliding surfaces 36a and 36b

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which lies between the ends of the drivers 37 and 38, depends.

The slide rod 36 comprises two sections 36e and 36d of enlarged diameter (Figure 11), which form a sliding guide with the longitudinal bore of the drive shaft 16. The cable of the rod, which extends to the right from the enlarged section 36d, has a smaller diameter and extends beyond the right end of the drive shaft 16 »As the right end (Fig. 1) of the part with reduced diameter, the slide rod 36 carries a link 39» which is shown in detail in Pig. 19 is shown and secured against turning with the rod. Furthermore, this member is secured against axial displacement relative to the slide rod by means of a S- ^ eliringes 40 and a locking ring 40a. On opposite sides, the adjusting ring 40 is held on the slide rod by an adjusting screw. The member 39 is provided on opposite sides with a cylindrical projection which has a groove 39a on each side of a square central portion. Furthermore, this member has a slightly enlarged head 39b outside the groove 39a. The grooves serve to receive the forked, lower end of arms 41a of a two-armed lever 41 which is pivotably arranged on a fixed axis © 4g {Pig * 1 uad 5). Adjusting ring «42a

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and 42 "b are fixed on the axis 42", us the lever 41 in the correct axial. position relative to the rod. Starting from the axis 42, another pair of arms of the lever 41 extends to the open. A coil spring 43 gemmdsne about the axis 42 stands at one end with a pin 44 fastened in the cable ring 42h and at its other end 4-3a, which runs in the direction of the antenna, with a? Pin 41c is engaged. The pin 41c is carried by the downward arms 41a of the lever 41. The P _e of 43 serves to bring the lever 41 with its Annen normally counterclockwise Uhrzeigerainn (]? Ig "" r) for engagement with a stop 45 to ", which in one a in the Pig. 6,7 and 8 is shown. The stop 45 is wnä hefestigt to own cord or a wire rope 46 through Ver-Ehiehen thereof vertically movable, as will be described in detail. The cable pull 46 extends downward through an opening 45a inside the stop 45. The latter is clamped in a certain position with respect to the cable by a clamping screw screwed into a threaded opening 45b.

The rope 46 is wrapped around a wheel 47, which is described in detail in Pig. 18 shown and freely rotatable on the conical part a screw 48 inserted into a pivot lever 49 is mounted. The latter has a hub 49a at the upper end,

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which is connected to the shaft 50 by clamping screws 491), which extends transversely through the vertical stand of the housing and in corresponding bearings in the front and rear walls the same is stored. For the purpose of assembling the ropes be ~ the shaft 50 consists of zyei pieces, which, as in ^ Oa in Pig. shown engaged with each other and mutually over the hub 49a are connected. The upper end of the rope 46 is preferably one twice by a reduced portion 51a Wheel 51 wound, which is rotatable about the shaft 50. One turn of the rope extending around the wheel 51 is through an opening 51b out. The free ends of the rope are, after they have been put around the wheels 47 and 51, together connected by an element 46a which is clamped to the overlapping free ends of the rope by means of a clamping screw.

The wheel 51 is provided with slots 51c in diaraetrically opposite areas of a cylindrical part, which receive projections 52a of an InP ig. 16 is provided so that both can be rotated together relative to the shaft 50 on which the bush 52 is mounted. At the left end of the socket 52 (Pig. 5) there is a scale disk with a knurled outer surface by means of a clamping screw

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53a attached, the dial plate 53 and an adjusting ring 52b, the on which Buohee 52 is attached, serve to counteract the socket

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A slotted hub 54a of an actuating lever 54 is attached to the scale on the shaft 50. A screw or bolt 54b is used to claw the hub on the shaft. The SkäLa can be rotated manually, independently of the pivoting movement of the lever 54, and by actuating the latter when it is pivoted downwards. To this end, the lever 54 carries, as best from Pig. 20 and 21, a spring-loaded pawl 54c with a slightly pointed surface 54d "which interacts with the depressions of the knurled surface of the scales" neeaeibe 53. In this way the SkaiMnaschsi.b,! "09i actuation 3®e H« oo.l.3 ~ l · sB ^ sncissen and twisted, but can also be relatively nüa 3el) & 1 54 g &%? 3h ^ wzva &'z .., jfobei the pawl from the indentations of the knurled surfaces of the scale disengage.

If you want to change the set stitch length, you only need to turn the dial by hand, and until the desired number appears in einar opening 54e (Fig. 3) of the operating lever 54, whereby the number the stitches per inch is displayed. By twisting it

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Dial will rotate the socket 52 and the Radeo 51 and thus a shifting of the cable 46 causes, which in turn the position of the stop »45 relative to the arm 41b of the lever B 41 is changed. On the other hand will in the case of a downward movement of the actuating lever 54, this is not the case only the socket 52, tibar rotated the 'pawl 54o, but in in the same way on the shaft 50 »so that the pivot lever 49 is pivoted. It follows from this "that the cable pull is not moved relative to the pivot lever 49, but that by the Pivoting the latter by means of the stop 45 the arms 41b can be swiveled clockwise and with the help of the arms .41a Qin shifting the slide rod 36 to the left is effected. As a result of this, the inclined sliding surfaces = just moved 36a and 36b to the left and cause one Upward movement of the pin 37 (Pig. 11) radially outward, whereby a corresponding displacement of the eccentric part 31. ! of the eccentric 32 takes place. The arrangement is such that a downward movement of the actuating lever 54 by the maximum pivoting path, regardless of which stem length is currently set is, the eccentric in the set eccentricity is adjusted by 180 ° and thus causes a reverse feed,! and that of the same handle length to which the device j is set for normal feed.

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The limitation of the movement of the operating lever 54 is effected by a bracket 55, which with screws 56 on the Front of the overhanging arm of the machine is attached. That is the amount that the planer moves down by an inwardly extending portion 55a aa lower end of the console, which cooperates with the lower surface of the lever 54, is determined. The normal position of the Lever under the action of the spring 43 is through a sioh after internally extending shoulder, not shown, determined immediately below the lowermost of the two screws 56. When the operator releases the lever 54, this returns to the normal, upper position by the action of the spring 43. The spring Φ3 is used to move the lever 41 counterclockwise to pivot, so that the latter interacts with the stop 45 moving the levers 49 and 54 clockwise causes.

The stop 45 is provided adjacent to its center point with an opening 45c which cooperates with the pivot lever 49. The opening ensures proper movement and guidance of the stop 45 when it is moved to change the stitch length will. In addition, as shown in Figs. 5 and 13, the pivot lever 49 is provided with a shoulder 49c, which serves to facilitate the upward movement of the stop 45 along öem

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Limiting lever and thus turning the dial Prevent BU. The downward movement of the stop 45 is through Impact on the disk 55 is limited, so that over-rotation the scale in the opposite direction is also prevented is.

The mode of operation of the material feed device and the manner in which the feed rate is awake - during each movement cycle of the machine and the direction of the feed can be controlled from the description above. It becomes "asfl according to the invention a very reliable and accurate ". '■ adjustable mechanism to control the stitch length and

Reversal of the feed direction proposed, which does not cause any disturbances when the machine is running at high speed, for example 6000 or hi & hr C) '''''' revolutions per minute. The control of the stitch length or the number of stitches per unit of length is achieved by changing the position of the connector 45 when the dial 43 is threatened. The higher the stop 4-5 rests against the pivot lever 49 by turning the dial and the resulting shifting of the cable 46, the shorter the fabric feed and the greater the number of stitches per unit of length. This is clearly shown in Fig. 1, from which it can be seen that when the stop

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45 is pushed up and the pivot lever 49 ia its Position remains, the Hß "bel 41 swings out in a clockwise direction and thus the slide rod 36 pushes to the left, whereby the The amount or size of the eccentricity of the eccentric is reduced. It is also from Pig. 1 to see that the higher the stop 45 stands, the less the lever 41 when pivoting of the lever 49 by depressing the operating lever 54

is pivoted. This is due to the fact that when the lever 49 is pivoted through the same angle by pressing down " of the operating lever 54 in its lowest position the effective length of the pivot lever 49 from the axis of the shaft 50 to the adjacent surface of the stop 45 is reduced becomes when the latter moves up. At the same time, the effective length of the arms 41e is increased. From it The result is that the longitudinal movement given to the slide rod 36 is reduced when the stop 45 is upwardly pushed will.

Another important point of the invention is that the adjustable part 32 of the eccentric is positively displaced in one direction or the other by the inclined sliding surfaces 36a and 36b of the sliding rod 36. No spring is provided in this area of the drive-in device. A spring 43 is found Ie ₇ -aiglieh in the area of those means ^ which the slide rod 36

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usually move closer to the right (Pig. 1). The position of the Slide rod 36 is not adversely affected when the machine is running at a high speed. The small angle of inclination of surfaces 36a and 36b (about 10 °) and the cooperating ends of the Pins 37 and 38 have the effect that there is no tendency that eats the Slide rod 36 moves at the speed of the machine. Your position becomes exact and perfect by the position d <33 Stop 45 is determined relative to the arm 41b of the lever 41. Pemer serve the slight inclination of the planes on the pins 37 and 38 in the in Pig. 11 and the clamping screws 37a and 38a holding the pins for securely holding the eccentric against accidental displacement.

In the illustrated embodiment of the invention, the adjustable dial cannot be brought into a zero position. If this should be desired, simple precautions can easily be taken to allow the stop 45 to be moved upwards to a PUr ¹ Ct ζ α which is aligned essentially horizontally with the axis of the shaft 50. At the same time, the arms 41b are lengthened to such an extent that they interact with the anchor sleeve 45 in this uppermost position. Perner can in a design that does not require reversing the eccentricity of the Exaentere 31, the inclination of the arms 41.b so that the slide rod 36 a

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ordered within an oil-tight housing. Different openings and channels are provided to S _c hroiermiiJtel a lever on the one bearing surface for piercing, a lubrication need in shape. The opening 39c in Pig, for example, is used for this purpose. 19th

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zeroing the eccentricity when the stop 45 "is in its uppermost position in the construction shown. This could, for example, be the pail if the machine according to the invention is used to move any other, reciprocating Parts within the machine, e.g. the needle bar of a zigzag machine, is used. The adjustment of the eccentric in its concentric position could e.g. be done * around a straight To make line of stitches.

A large part of the described control mechanism of the machine P * -

Claims (6)

RA. 316 0ß0 * 6/19/65 A 34 509 π η - 123 6/15/1965 - 24 - responses! 1. Fabric feed device for sewing machines, where the Feed movement of a material pusher of size and sighting by an eccentric member rotating with a drive shaft and radially provided by means of an inclined guide s- is adjustable, characterized _r HäaB inside the hollow drive shaft (16) is arranged a _{sliding rod (36), which can be adjusted by external means (5i r} 53,49,41), in which sliding surfaces (36a, 36b) running obliquely on the shaft (16) are recessed, and the radially displaceable eccentric member (32) has two drivers (37, 38) which engage in the hollow drive shaft (16) and rest with their ends on the oil surfaces (36a, 36b). 2. Device according to claim 1, characterized in that the driver (37,38) designed as a pin «and adjustable are held in the eccentric member (32). 3. Device according to claim 1 or 2, characterized in that that the sliding surfaces (36a, 36b) are inclined to the axis of the drive shaft (16) by an angle of about 10 °. - 25th A 34 509 so a - 123 June 15, 1965 - 25 - 4. Apparatus according to claim 1,2 or 3, characterized in ₅ that the slide bar (36) is articulated on the one Ann (41a) of a two-armed lever (41), the other arm (41b) at a Sohv / enMiebei (49) is present, which in turn can be swiveled via its operating lever (54-) ο 5. Device according to claim 4, characterized in that for setting the size of the eccentricity of the eccentric (32) the pivoting range of the lever (41) can be adjusted by moving its contact point (45). 6. Device according to claim 4 or 5, characterized in that the pivot lever (49) has a . The stop (45) which determines the contact point of the plane = arm (41b) is provided, which is adjustable via a cable pull (46) and a graduated disk (53). 7 ·? _T means according to claim 6 characterized in that the adjustment of the stroke (45) on the pivoting lever / is limited 49) by a shoulder (49c) "