DE2828083A1 - Sewing machine - with control device for automatic adjustment of needle thread brake - Google Patents

Abstract

Sewing machine having a controlling device for automatic adjustment of needle thread brake has a stitch formation for setting the position of the needle and the sewing article per stitch and a manually controllable defice for desired fractional setting of the preset needle and article position per stitch. Manually controllable devices act also on controllers provided with springs which exert the required braking force automatically on the needle thread. Controlling device further includes a bobbin thread brake spring, which is preset in a known manner to exert a preset braking force on the and effect the desired equilibrium between the two threads.

Description

, '' · * "· ··· ι ··
, · ..." .1
,. · · · ♦ Il
., ■, I ■,. »· Ir Wolfgang, angel 2828083 Elbinger Strasse 36 B 7500 Karlsruhe sewing machine ■ The invention "relates to a sewing machine with a through Control means automatically adjusted needle thread braking device tion. The location of the knot from needle and bobbin thread of a double quilt The stitch seam should be approximately in the putty of the fabric thickness to be sewn so that neither a claw thread nor a bobbin thread are loose on the fabric 5 lying and without the fabric puckering. When changing the position of the However, the needle and / or the workpiece to be sewn changes In general, also calibrate the position of the knots in the fabric. It is then required the needle thread braking device through the loading to hire a new operator. It should be noted that in the 10 generally increasing the stitch length increasing the Needle thread braking force and an enlargement of the stitch field width Requires lowering the needle thread braking force. Are stitch length ge and stitch field width changed at the same time, a result will be ting needle thread braking force required. It can be seen 15th that the setting of each opti for the operator paint needle thread braking special sewing experience and also sewing samples required. Additional adjustment problems generally occur mean, for example, when sewing a wide variety of fabrics or with extreme roughness of the yarn or when with ei 20th n some sewing machines, in special cases, the bobbin thread braking force must be adjusted by hand. A main aim of the invention is to balance the Tension forces of the needle and bobbin thread at the knot from both threads that in the material itself, despite all the influences mentioned, to a large extent 25th actively produce. It is an object of the invention to provide a sewing machine with such 909881/0370

To create control means that the needle thread brake device automatically adjust to the required braking force, which is any desired fraction of both that set per stitch Corresponds to the position of the needle as well as the position of the workpiece to be sewn set for each stitch. Differently * presses, with each actuation of a handle for the setting of any stitch length and / or stitch field width should the needle thread brake device adjusts itself automatically. The tension forces of the needle and bobbin thread on the Knots in the fabric must be the same size.

They are sewing machines with a stitch pattern field memory, i.e. with several selectable, predetermined settings of stitch length and / or stitch field width became known (USA-PS 3075 483). It is also known for a sewing machine, another Setting device for several settings can be predetermined (GDR-PS 19597). Loosen these sewing machines but not the problem of the automatic adjustment of a needle thread braking force as a function of the selected stitch pattern field. Another sewing machine (DT-OS 2728 ^ 35) is although a stitch pattern field memory designed as a control cam package with a cam for the predetermined setting of a Needle thread braking force - preferably for buttonhole sewing. intended. But only a single predetermined setting of the needle thread braking device is provided and possible there the cam has two functions at the same time. He couples the feed block respectively. the setting with a stop, the setting of which can be predetermined by the stitch pattern field memory, and

of two

it determines the spring length of a needle thread brake spring.

It is therefore a further object of the invention to design sewing machines with stitch pattern field memory so that the needle thread braking device is automatically adjustable to each selectable stitch pattern field and the tensioning forces of the needle and Bobbin thread at the knot of both threads in the fabric are the same size

909881/0370

be.

It is also an object of the invention to provide a sewing machine with such To create control means that automatically adjust the needle thread braking device to each stitch of a stitch pattern can, whereby the tension forces of the needle and bobbin thread at the knot of both threads in the fabric are the same should· .

So far become known sewing machines with two memories a tichmuster for S and a stitch pattern fields - _t with an additive selection system is set at the same time an adjustment of a stitch pattern field in which therefore the choice of a stitch pattern (DT-OS 2,359,232, DT-OS 2,609,238) serve the purpose to achieve an exact multiplication of a typical or illustrated stitch pattern effortlessly at any time. The required needle thread braking force is, however, a function of the selected sewing task, ie the selected sewing operation and type of fabric, ie the selected stitch pattern and stitch pattern field. It is therefore an aim of the invention to make the known additive selection system suitable for the selection of sewing tasks and at the same time to automatically adjust the needle thread braking force when making the selection.

In order to give the operator a choice, it is an object of the invention to provide the same braking element of the needle thread braking device influence ru "either through automatic or manually controlled means"

However, according to a further object of the invention, the automatic control means are also intended to be the braking element of the needle thread braking device optionally to predetermined or to any desired fractions of the position adjustment of the needle and the workpiece to be sewn.

All of the above-mentioned individual objectives of an overall objective of the invention relate to the setting of a needle thread braking device with a setting device in a 3-inch

Adjustment process. It is another object of the invention to compensate several influences - predictable and / or not

predeterminable - on the needle thread according to cause and size h

by several adjustment devices in several adjustment devices; |

went on at the same time or one after the other. So lets ■ '

the balance of the tension forces of the needle and the spool .1?

lenfadens at the knot from both threads in the fabric optimal and '<

Manufacture largely automatically. >,

Ss is also an object of the invention to provide control devices for; i>.

automatic adjustment of the needle thread brake element to k ■

Predeterminable Influences Unpredictable Influences such as Ii

e.g. extreme degree of roughness of the thread or extreme number ff.

to make the fabric layers to be sewn adaptable, ψ

One aim of the invention is to achieve as many predetermined settings as possible of the needle thread braking element with little effort to be able to select, in order to create the prerequisite for a selection device of predetermined Naclelfadenbremskraft their Display device shows sewing operations and their stitch patterns as well as types of fabric,

It is an object of the invention to provide a needle thread braking device:

device for the usual manual control of the braking force | v

of the braking element also for the automatic control (>

turn around. . '■ ■. fr)

The aim of the invention is to create electrical control I '

devices that affect the setting of the needle; ■■:

take thread braking element. , p

The following are examples of execution on the basis of drawings; ^: ,

games of the invention explained. . %.

909881/0370

Figure 1 is the representation of the result of a sewing test in the form of a table, the influence of the change in Settings of stitch field width and stitch length on the required needle thread brake device on a zigzag sewing machine shows an example for lockstitch.

FIG. 2 is a basic illustration of the known knot formation of needle and bobbin thread in lockstitch sewing machines with the action of the needle and bobbin thread braking device.

Figure 3 is a plan view of a needle thread braking device according to the invention for small control paths and high control speeds and in a unit with one of Hand adjustable device for selecting any desired fraction of stored signals for adjustment the needle thread brake spring.

FIG. K is a front view of a needle thread braking device according to the invention in a partially sectioned illustration - according to the section line h ~ k in FIG.

FIG. 5 is a side view of the needle thread braking device according to the invention according to FIGS. 3 and k.

Figure 6 is a perspective view of a zigzag sewing machine; which parts of a typical drive mechanism and the arrangement of a braking device for the Shows needle and bobbin thread.

Figure 7 is a needle thread braking device for small control paths in a sectional view *

Figure 8 is a perspective view of a needle thread brake device according to Figure 7 in individual representation.

909881/0370

FIG. 9 is a side view, partly in section, of a control device according to the invention for the automatic adjustment of the needle thread brake device with manual operation of the stitch length and / or stitch field width.

FIG. 10 is a side view of that shown in FIG Control device. . '·

FIG. 11 is a plan view of the control means of the control device which regulate the material feed Figures 9 and 10.

Figure 12 is a plan view of the needle thread braking force regulating control means of the control device according to FIGS. 9 and 10.

Figure 13 is a plan view of the stitch field width bezv /. Stitch field position regulating control means of the control device according to Figures 9 and 10.

Figure I ^ is a partial perspective view of the needle thread braking force regulating control means according to Figure 12.

Figure 15 is a partial perspective view of the stitch field width respectively Control means regulating the stitch field position according to FIG. 13.

Figure 16 is a partial perspective view of the sewing machine of Figures 9 to 15 showing the arrangement of the handles shows.

25 _y 17 is a side view in partial cross section of an inventive control device for the automatic adjustment of the needle thread braking device for manual operation of a control formed as a disc package stitch pattern field memory.

909881/0370

• · · · · · ItI

• · · · · · III

Figure 18 is a side view of the individual in Figure Cam follower members assigned to the control disks shown.

Figure 19 is a plan view of the needle thread braking force 'regulating control means of the control device according to Figures 17 and 18, which the position of the follower member and shows its sliding surface with manual control of the braking force.

FIG. 2o is a plan view of the control means of the control device according to the figures, which regulate the material feed 17 and l8 in the position of the trailing link with manual control of the stitch length.

FIG. 21 is a partial side view in section of a storage and selection arrangement according to the invention for both stitch patterns and stitch pattern fields with automatic adjustment of the needle thread brake device at any choice.

Figure 22 is a partial perspective view of a zigzag sewing machine with a control device according to the invention according to FIGS. 17 7 21 »

FIG. 23 is a diagram of cam paths elue of the stitch pattern field memory of a control device according to FIGS . 17 and 22, designed as a control disk package.

Figure Zh is a side view in a partially sectioned representation of an inventive

Furnishings. for automatic

Setting of the position of the needle, the workpiece and the needle thread brake spring per stitch and. with tax revenue . for the automatic adjustment of the Madeladenbrinsfeder when setting a stitch field width and a stitch length.

909881/0370

• ♦ t i t ι «ι V

> ι ι ι ■ '■: ·;

FIG. 25 is a further side view of the device shown in FIG
Shows trailing elements of the control disks.

FIG. Z6 is a plan view of the control means of the device according to FIGS. 2 ^ and 25, which regulate the material feed.

Figure 27 is a plan view of the needle thread braking force
regulating control means of the ·. - Device according to Figures 2'r and 25.

Figure 28 is a plan view of the stitch field width or.
Stitch field position regulating control means of the device according to Figures Zk and 25.

Figure 29 is a side view partially in section a control device according to the invention

with a facility. for the automatic adjustment of the needle, workpiece and needle thread brake spring
per stitch and with one. Device for the predetermined setting of stitch field width, stitch length and
Needle thread braking force by means of a control disk package _; ]. ·. '

trained sample field memory. ^

FIG. 30 is a plan view of the control means of the control device which regulate the needle thread braking force U;

Figure 29.. ,. ^

Figure 31 is a plan view of the locking device of the control ^ i

disk package for the predetermined stitch pattern- ji) feider of the control device according to Figures 29 and 30. j

Figure 32 is a partial perspective view of a sewing machine;

; with a control device according to FIGS. 29 to 31 J

with display of the selected sewing operation and the off-> selected type of fabric.

909881/0370

Figure 33 is a perspective view of a sewing machine according to the invention showing the physical elements in an embodiment with electronic Control device according to the invention necessary is.

Figure 3 ^ is a block diagram for a sewing machine accordingly FIG. 33 with a circuit diagram-like representation of the potentiometers that are used in a sewing machine according to FIG of the invention were used and which influence the automatic control of the needle thread braking device to take. The potentiometers connected in series for the resulting fractional setting of the Spring tension of the needle thread brake: each time the Stitch pattern field can be in an embodiment of a battery operated energy source (solid lines) or in another embodiment of the Stitch pattern memory (dash-dotted lines) are fed with energy «

FIG. 35 is a partial perspective view of a sewing machine with an electronic control device according to FIGS. 33 and 3k and it particularly shows the arrangement of the handles.

Figure 36 is a block diagram for a sewing machine according to Invention with a circuit diagram-like representation of both the potentiometer and the eight-way switch that are optionally switchable in the circuit. Dashed lines indicate the circuit diagram that is required is when it is powered by the stitch pattern memory instead of the battery.

Figure 37 is a perspective partial view of a sewing machine according to the block diagram of Figure 36-

909881/0370

Figure 3δ is an enlarged representation of a display input · direction of figure 37.

FIG. 6 shows a sewing machine 11 which has a workpiece support plate 12 from which a stand 13 rises which supports a machine arm 1k which hangs over the plate 12 and over which a cover 15 is shown in a see-through representation. The machine ^{arm I 1} * ends at the free end in a sewing head 16, in which parts of the stitch-forming tools of the sewing machine 11 are attached, which include a needle 20 which cooperates with the gripper 28 in the plate 12 in the formation of stitches. The needle 20 is carried by a needle bar 21 which can be reciprocated in a needle bar rocker 22 in its longitudinal direction, and the needle bar rocker 22 is mounted on trunnion bearings 23 in the sewing machine head 16 for lateral swinging movements which lead to the formation of zigzag stitches. A handlebar 2, which is pivotably connected to the needle bar swing arm 22, serves to give the swing arm 22 lateral swinging movements.

Workpieces are against the thrust of the penetration of the needle 20 through a needle hole plate 27 on the workpiece attachment plate 12 supported, and the workpiece held on the needle plate 27 by a presser foot, not shown, which is of a Push rod 29 is carried, which is displaceable in the sewing head 16. Under the needle hole plate 27 there is a Knife pusher 30 carried by a pusher rod 31, which passes through slots located in the needle hole plate 27 is working. By means of a pivotably arranged link 32, the slide rod 31 is connected to one that lifts the knife feeder Swivel arm 33 connected, which extends from a world 3 ^ stored in the plate 12. The other end of the slide rod 31 is pivotably connected to a pivot arm 35, which is carried by a feed pivot shaft 36 which is in the

909881/0370

Workpiece support plate 12 is mounted. A pivot arm 37 on the feed pivot shaft 36 below the plate 12 is pivotably connected to a swinging control rod 38. The control rod 38 comprises a fork-like eccentric which is attached to a shaft driven by the arm shaft in a ratio of 1: 1 and thus receives its vibrations. The control rod 38 carries a guide pin 39 which is held within a guide slide kO, which is formed in a feed controller block kl, which is located at one end of the feed controller shaft 119 mounted in the machine frame below the stand 13. The other end of the feed regulator shaft 119 is connected to a pivot arm 125 to which the link k2 is articulated, which is used ^{to transmit sliding movement to the feed regulator block 1} H in order to control the direction and the size of the stitch length.

The embodiment described so far with regard to the needle pivoting mechanism and the workpiece feed mechanism represents common stitch-forming tools in sewing machines. For stitch formation The hook also belongs to lockstitch sewing machines 28 with its bobbin case lo ^ f carrying the bobbin thread brake spring 103 and the needle thread brake device 90. With the help With both thread brake devices, the position of the knot in the fabric can be optimally adjusted.

Figures 9 to 16 show the example of a zigzag sewing machine the automatic adjustment of the needle thread brake device with any desired setting of stitch field width and / or stitch length according to the invention.

The worm kk mounted on the arm shaft k3 mounted in the machine arm I ^ drives the worm wheel 46 mounted on the axis k5 mounted in the machine arm l * f, which is integrally connected to the zigzag cam hy and is expediently molded from plastic. For manual adjustment there are k? On axis J + 5 above the zigzag cam disc. the curve

909881/0370

be for stitch position 48 with a cam track 4-9, the double cam 50 with a curved path 51 for the stitch field width and another curved path 52 for the spring 89 of the Needle thread braking device 90 and the double cam disk 53 with a cam track 54 for the stitch length and one other cam track 55 stored for the needle thread brake.

There is a handle on each of the three cams 48, 50 and 53 56, 57 and 58 attached, from the sewing machine arm l4 protrudes. The three cam disks are against axial displacement 48, 50, 53 and the worm wheel 46 with zigzag cam plate 47 secured by five lock washers 59, which engage in corresponding grooves in the axis 45. Against Unintentional pivoting, the cam disks 48, 50, 53 are secured in that the handles 56, 57, 58 from one elastic material, preferably spring steel, resiliently resilient on their slot edge in the sewing machine arm 14 support and thus act as a brake.

Those working together with the cam tracks 47, 49, 51 * 52, 54, 55 Follower members 59 to 64 are mounted on axles 72 and 88 and secured against axial displacement by locking washers 63 ', which engage in grooves on axles 72, 88 «

The trailing element 60 scans the curved path with its probe tip 65 49 of the cam 48 for the stitch position is stored on the axis 72 and has the bore 6,6 in the area of the probe tip 65, in which the bolt 67 is stuck on the the follower member 59 rotatably mounted and the locking washer. 68 is attached to axially secure the follower member 59, the probe tip 70 of which with the curved path of the zigzag curve disc 47 cooperates. Along the sliding surface 69 can the probe tip 71 of the handlebar 24 can be moved. For this purpose, the trailing link 6l designed as a double plane is on the

■ ■ ■■>

909881/0370

ft ·· »* · · ■ · 1111» »

• t t ·· »··· l» f

• ti ·· * »# * ι · ■

Axis 72 rotatably mounted, works with its probe tip 73 with the cam track 51 of the cam disk 50 for the stitch field width, has at the end of the other lever arm '7 ** the hole 75 in which the bolt 76 is stuck. The link 77 is rotatably mounted on it and is secured against axial displacement by a locking washer which engages in the recess 8o. At the other end of the link 77 there is the bore 78 in which the bolt 79 is firmly seated and enters the bore 81 of the link 2k , which is secured against axial displacement by a locking washer which engages in the recess 82 of the bolt 79.

The lever 83 is rotatably mounted on the axis 88 and secured against axial displacement ^{by locking washers 63 1.} The end of the lever 83 has a bore 8k through which the bolt 85, which is firmly seated in a bore of the balance lever, protrudes and carries a locking washer 87 to secure the bolt 85 axially. The balance lever 86 carries the probe tip 62, which cooperates with the cam track 52 for the spring 89 of the needle thread brake device 90 and the probe tip 63 »which cooperates with the cam track 55 for the spring 89 of the needle thread brake device 90 by means of the spring 89. The resulting setting of the lever 83 resulting from an adjustment of the handles 5δ for the stitch length and 57 for the stitch field width is via the probe tip 92 of the link 91, via the angle lever 93 mounted in the machine arm Ik and via pin 9 ^ and washer 95 on the The spring 89 of the needle thread braking device 90 is transmitted, which thereby exerts a corresponding force on the needle thread tensioning disks 96, 97, 98, which are supported against the shoulder 99 of the bolt 100. This is screwed into the bushing 101, which is fastened in the machine arm Ik by means of the screw 102.

A table is shown in FIG. 1, which shows the necessary equalization of tension in an experimental sewing machine

909881/0370

CZ ; i_

lh

shows the same tension forces in the needle and bobbin thread at the knot to reach. The setting digits refer to one from O to 9 resp. adjusting nut adjustable by approx. 320 ° and open a spring deflection of approx. * + .0 mm, where 2 corresponds to Q5N and 6 corresponds to 1 ^ 75N,

Figure 2 shows the "knotting principle on which the table in Figure 1 is based. In Figures 1 and 2, the bobbin thread spring force P- = C (constant) of the bobbin thread spring 103 of the bobbin case 10 * +, P. the tension force acting in the bobbin thread at the knot, P, the necessary needle thread spring force, which is determined by the position of the needle and / or the workpiece, and Pr = P ₂ the tension force acting in the needle thread at the knot with the optimal position of the knot of needle and bobbin thread in the fabric.

To avoid the control paths for the equilibrium compensation, that is to say the pivot angle and the length of the balance lever 86 To keep large construction parts small and to save adjustment parts, the spring 89 works directly against it the setting cam disks 50, 53 instead of an otherwise customary setting nut sitting on the bolt 100 with a thread In rare cases there are deviations from the basic braking force ratio Both brakes are necessary to each other, which is the basis of the program that is stored in the cam tracks 52 and 55 lies.

This is also the case in such cases with all stitch field width settings and the stitch length to achieve correct automatic adjustments of the spring 89, the lever 83 has a sliding surface 105 on, along which the probe tip 92 of the handlebar 91 can slide in order to adjust fractions of the programmed spring travel of the spring 89 can. For this purpose, the im Sewing machine arm I ^ attached axis 106 of angle lever 107 rotatably mounted, one leg IO8 of which carries a handle 109 and the other leg 110 carries the pin 111 on which rotatably a handlebar 112 is attached to its other

909881/0370

• ff

End rotatable with the handlebar * -ß. connected is. The angle lever I07 is secured against axial displacement on the axis IO6 by two locking washers 113 »II ² *. Spring washers 115 are provided as a brake against unintentional pivoting of the angle lever 107.

On the axis 72 is the trailing element designed as a double lever 64 rotatably mounted, works with its probe tip 116 with the cam 54 of the cam 53 for the setting the stitch length together. The leg 117 of the follower member 64 designed as a double lever has a at its end Hole in which a bolt II8, which is fixed in a handlebar 42 is arranged, rotatably mounted and secured axially with respect to the leg 117 by a locking washer 120. That the other end of the handlebar 42 carries an eye 121 molded from plastic, the spherical bore 122 of which surrounds the ball 123, which is located on the head of the bolt 124, which is in the swivel arm 125, which is connected to the feed regulator shaft and thus sets the feed regulator block 4l.

Figures 17 to 23 show a zigzag sewing machine with a predetermined setting of the needle thread brake spring, of stitch field width and / or. Stitch field position and stitch length for each selectable design field ¹ . The worm wheel 46, which is driven by the worm Mt and which is integral with the zigzag cam disk 4? is connected and expediently injection-molded from plastic, rotatably mounted. To select the predetermined settings, a one-piece set of cam disks is rotatably mounted as a stitch pattern field memory 127 with handle 134 on axis 126 & ■ above the zigzag cam disk hf and secured against axial displacement by locking disks 128 that engage in grooves on axis 126.

909881/0370

► · t

One after the other are the cams 129 for the stitch position, 130 for the stitch field width, 131 for the needle thread spring, 132 for the stitch length and 133 the locking disc arranged one above the other to form a package. The upper one from the cover 15 of the sewing machine the protruding part of the package 127 is a handle 13 ** formed, on the circumference of which setting symbols are shown for each detent position, which cooperate with an arrow 135. The handle 13 * l · is through a cover plate I36 'after closed at the top.

On the axis 72 the trailing elements δθ, 6l, 1 ^ 6 and on the axle 88 the trailing element 1 * K> for the spring 89 of the needle thread and the locking lever l * »l are rotatably mounted and secured against displacement by the locking washers 63 '. The follower 1 ^ 6 works with the cam 132, the follower IkQ works with the cam 13I, the follower 6l works with the cam I30, the follower 60 works with the cam 129, the follower 59 works with the cam k7 and the locking lever Hfl works together with the locking disk 133.

The trailing elements 146, 61, 60, 59 are in a kinematic connection according to FIGS. 9 to 15 with the needle 20 and the feed regulator block kl. The trailing link 1 ^ 6 differs from the trailing link 6k only by the extension 1 ^ 7. The trailing element l * fO is in connection with the spring 89 for the needle thread via the link 91 and the angle lever 93 according to FIG. 19 or 12. The locking lever 1 ^ 1 engages in the locking grooves of the locking disc 133 under the action of a spring.

In each detent position of the area 138 for predetermined one-positions the cam disk set 127 outputs setting signals through the corresponding height of the scanned cams or signal transmitters 137 for a sewing task and the associated spring travel

909881/0370

ι?

a spring 89 for the tensioning force of the needle thread, namely one to the feed regulator block * fl, two to the needle 20 and one to the spring 89 for the needle thread. The curved tracks or signal generator rows of the cam discs 129 »130, 131» 132 contain signals in the form of cams of different heights for all sewing operations and fabric groups shown in the display (f, 1, etc.). In addition to the peripheral area I38 for predetermined settings, the cam disk package 127 also contains one Circumferential range 139 for any desired setting.

This area 139 does not contain any latching positions. The cam tracks of the cam disk η for the stitch field width 130 and stitch position 129 are designed in this area 139 that when pivoting the handle 13 ¹ ^ in this area 139 the stitch field width increases from zero to five while the stitch position changes from left to center.

In the area 139, the cam path of the cam for the spring 89 of the needle thread runs at a maximum, around the angle of inclination adjust the sliding surface lA-2 of the trailing link l * f0 so that that when the probe tip 92 of the handlebar 91 glides along from point 1 ^ 3 via point lMf to point 1 ^ 5 the spring deflection the spring 89 is adjusted from zero to max. To adjust the probe tip 92 of the handlebar 91 along the sliding surface 1 ^ 2 the rotary handle 1 ^ 8 is used, the one on the axis 1 ^ 9 is mounted rotatably and axially secured, which is fixed in the machine frame. Against unintentional pivoting of the handle Brake disks 152 are provided in 148. That's an end of the Handlebar 151 is rotatable with a fixed in the handle 1 ^ -8 Bolt 150 and the other end of the handlebar 151 is rotatably connected to a bolt fixed in the handlebar 91.

I ^m corresponding to the region 139 KurvenbaLn for the cam disc I32 the largest reverse stitch, ie, the smallest web diameter. As a result, the cam path of the probe tip 153 of the trailing element 1 ^ 6 for the stitch length gives room if at

909881/0370

Pivoting the rotary handle 15 ^ for the stitch length adjusts the cam track 155 via the bolt 156 attached to the leg IhI, the follower link I * f6 and thus the feed regulator block * fl.

FIG. 21 shows a selection device for the same zigzag sewing machine according to FIGS. 17 to 20 and 22, which allows stitch patterns and several predetermined stitch pattern fields for each - that is, predetermined stitch field widths and Stitch lengths - to be selected. In this way, the spring 89 of the needle thread can be applied to several pattern fields of any chosen one Set stitch pattern automatically «

In place of the axis 126, the axis 157 is fastened in the machine frame lh , on which the worm wheel I58 is rotatably mounted and axially secured and which carries the pin 159 as a driver. A curve selection unit 160, which contains a drivable stitch pattern cam disk 16I, which has a driving groove 162 through which the pin 159 passes, can be plugged onto the axle 157. On the hub I63 of the stitch pattern curve thrusts οί the cam disk set 16 ^ is rotatably and axially secured, which has the cam disks 129 »130, 131» 132 and the locking disk 133. The cam disk package l6 * f goes up into a handle I65. The cam selection unit is secured against unintentional axial displacement by a groove I66 in the bore of the hub I63, into which the ball pin I67 engages resiliently. The cams 129 to 132 work together with the follower elements 60, 61, I ¹ K), 1 ^ 6.

Figures Zh to 32 show as an example two mechanically controlled ornamental sewing machines, in which the control cam disks driven by the sewing machine automatically adjust the spring of the needle thread braking device for each stitch in addition to the position of the needle and / or the workpiece, in order to adjust the position of the knot of an ornamental stitch -

909881/0370

to keep the pattern seam constant within the fabric thickness.

In the machine arm I ^ the arm shaft ^ is mounted, on which the worm kk is attached, which drives the worm wheel 168, which is firmly connected to the cam shaft 169. The cam disk shaft I69 is rotatably mounted in the bearing bush 10, which is arranged in a bore in the machine arm Ik and fastened by means of screw 171. Above the bearing bush 170, a drive disk 172 is shrunk onto the cam disk shaft 169, which carries the drive pin 173, which enters a hole in a triple cam disk package Yf k , which sits interchangeably on the cam disk shaft 169 and the cam tracks for the stitch length 189 for the needle thread braking force 190 and 191 for the stitch field width.

Furthermore, on the upper part of the bearing bush 170 protruding from the machine arm Ik, three manually adjustable cam disks are mounted rotatably but secured against axial displacement by locking disks 175.

The upper cam 17β is used to set the stitch field position. A hand lever 377, preferably made of spring leaf steel, is attached to it, which rests resiliently on the lower surface of a slot 179 in the machine arm Ik for the purpose of braking a set setting and carries a handle I78 at its end protruding from the machine arm Ik. The middle cam 180 has a cam path I8I for the stitch field width and a cam path I82 for the needle thread brake spring 186. It is set by the handle I83 and braked like the cam I76. The lower cam 18 ** has a cam track I85 for the sewing thread brake spring I86 and a cam track I87 for the stitch length. It is set by the handle 188 and braked like the cam I76.

The respectively with the cams. Cam tracks I89, 190, 191t

909881/0370

176, 18l, 182, 185, 187 cooperating trailing links 192 to 199 are mounted on axles 200 and 201 and secured against axial displacement by locking washers 202 and 203,

which engage in grooves of the axes 200 and 201, secured. |

The axes 200 and 201 are in turn in bores of the machine } \

nenarmes I ^ attached. The trailing element 192 gropes with its ·: ■

Probe tip the curved path I89 for the stitch length of an out- γ,

interchangeable triple curve package 17 ^ is stored on the? Axis 200, extended beyond this storage. This extension

Gerung 20 ^ includes with a fixed connection a tube 205, which is <>

just like the axis 200 down into the barely below the \: ':

Workpiece support plate 12 extends, in which the axis 200 / '

is mounted in a bore. A sliding surface lever 206 is i;

rotatably mounted on the lower end of the axis 200, against axi- f ^:

fr ales shifting secured by lock washers 202 and extended beyond these storage addition to comprise a fixed connecting the pipe 205th

A link 207 carries at one end a bolt 208 which works together with the sliding surface 211 of the sliding surface lever 206. The other end of the handlebar 207 carries a plastic

molded eye 209, the spherical bore of which the ball 123 '

which is located on the head of the bolt IZk , which is in>■;

the swivel arm 125 is firmly seated, which is connected to the feed regulator shaft U.

119 is connected. A tension spring 210 engages around with its one ψ

End of a pin 212, which sits firmly in the pivot arm 125 and with | -

its other end has a pin 213 which is in the fabric support plate | V

12 is tight. Under the action of this spring, the BoI- (>}

zen 208 to the sliding surface 211 of the sliding surface lever 206 and "

the probe tip of the follower member 192 to the cam track 189 ;; ■■;

for the stitch length of the triple cam disk package 17 ^. 'Ά

When turning the package 17 * f, the feed controller block kl \ - \

with his guide shoe kO according to the design of the $

Cam cams respectively according to the control signals ^; j pivots. These control signals stored per stitch for the

909881/0370

The position of the workpiece can be changed using the method described below

Means for manual adjustment of the stitch length can be adjusted to any desired fraction. The probe tip of the follower element 199 works together with the cam track 1 $ 7 e'er cam disk ISk _1, which can be pivoted by hand by means of a handle 188. The follower member 199 is essentially U-shaped, its two legs having bores for mounting on the axis 200. While the upper leg carries the probe tip at its end, the end of the lower leg, which extends below the fabric support plate, has a Bore in which a pin ZIk is rotatably arranged, which is fixedly connected to the handlebar 215, which at its other end carries a further pin 2l6 which is fixedly connected to the handlebar 215 and which is rotatably mounted in a bore of the handlebar 207. These pins 21 * f and 216 are in the usual way against axial displacement with respect to the handlebar 20? resp. lower leg of the trailing link 199 secured. When the handle 188 is actuated, the cam track 187 is pivoted. The probe tip of the trailing element 199 follows the curve shape of the cam track l87 under the action of the spring 217, so that the bolt 208 of the link 207 pivots in a circular arc around the ball 123 of the bolt 124 along the sliding surface 211 of the sliding surface lever 206. At the same time, the ball 123 pivots, inter alia, the feed regulator shaft 119 and thus the feed regulator block kl with the guide slot kO. The arrangement of the pivot points is provided so that when the triple cam set 17 * t is rotated and the handle I88 for the fractional adjustment is not operated while the ball 123 is pivoted about the feed regulator shaft 119, there is practically no sliding friction between the bolt 2θ8 and the sliding surface 211 . This is achieved essentially by the arrangement and length of the handlebar 215. "

While previously described how

the cam cams of the driven cam I89 for the

909881/0370

rv:

Position of the workpiece per stitch as well as the cam track I87 of the manually pivotable cam 18 * »·" · act on the position of the guide slot ko , is described below how the cam cams of the driven cam 190 for the needle thread brake spring 186 -

. as well as the curved tracks l82 and I85 of the manually swiveling ones Cams 180 for the stitch width and l84 for the stitch length '- · ■ ■■> affect the travel of the spring 186.

The follower member 193 is rotatably mounted on the axle 201 and has a probe tip which cooperates with the driven cam disk 190 for the needle thread brake spring I86 and it has a sliding surface 218 which cooperates with a probe tip of the handlebar 219 on its other End carries a second probe tip which rests on a sliding surface 220 of a lever 221 which is rotatable on a hub 222 (Figures 3 to 5) of a lever 228 is mounted, which in turn is rotatably mounted on the bolt 22 * 4 »The exact angular position Both levers 221 and 228 can be locked after adjustment by means of screw 236. Through the two locking rings 225, the lever 228 is secured against axial displacement with respect to the bolt 22 * f. He has a fork on one end 229 »a thrust washer 230 articulated in its two bores stored int by means of the two pins 231. The conical needle thread brake spring I86 is supported with its smaller diameter on the pressure disk 230 and with its larger diameter on an upper needle thread brake disk 233. For sewing With two needle threads, a disk 23 ** is provided between the upper and lower disk 233. All three disks 233t 234 are supported on the shoulder of the bolt 232, which is fastened in the bearing block 2P6. The bearing block is with the screws 227 attached in the machine arm I ^. The disks 233 »23 ^ are in the usual way secured against rotation by the bolt 232 is slotted and the holes in the discs with which they

909881/0370

♦ · m

»Til ti

I · ι

t.

are mounted on the bolt 232, interrupted by webs which engage in the slot of the bolt 232

The tip of the link 219, which cooperates with the sliding surface 220, can be adjusted by hand along the sliding surface 220 in order to correct the stored spring length. For this purpose, a knurled adjusting knob 253 is rotatably mounted on the bolt 22 * t and braked against unintentional adjustment, in which a spring washer 2 ^ 3 is supported on a ^{locking ring 2 ^ 2 attached to the bolt 22 1} V and with the interposition of a washer Zkk presses the adjusting knob 253 against the locking washer 225. An eccentrically arranged hub 2 * tO of the rotary knob 253 is surrounded by an eye of the lever 238, which carries at its end a pin 237 which rotatably moves in a bore of the handlebar 219 and a see The washer helps to axially secure the handlebar 219 · The rotary knob has symbols, for example, for the position "normal", "increase" and "reduce" of a stored signal for the spring length of the spring 186.DiOrCh turning the rotary knob 253 is therefore the effective translation of the lever 221 and 228 and thus the effective spring travel within the braking force range is changed.

The cam shape of the driven cam disk 190 for the needle thread brake spring 186 is based on the maximum possible overlap width and stitch length of the associated driven cam disks 191 for the stitch width and 189 for the Stitch length, related to the sewing operation, of the selected Stitch pattern is assigned. If these values are reduced by Setting the cam I80 for the stitch width and / or the cam disk 184 for the stitch length by means of the handles 183,188 must also have the stored signals for the The spring travel per stitch corresponds to the selected fraction setting adjusts itself at the same time as the stitch width and / or the stitch length automatically determines the position of the probe tip of the link 219 along the sliding surface 213 of the trailing element 193 by

909881/0370

Stitch width is l8o pivots the cam plate and thus its Kuryenbahn L8L _t with which cooperates the probe tip of the tracking member 196 by the spring 250, which is rotatably mounted on the axis 200th The follower link I96 is designed as a double-armed lever, one arm of which carries the probe tip and the other arm is pivotably connected to the link 256 by means of a bracket 258 in order to move its probe tip along the sliding surface 255 of the follower link 195.

To replace a triple cam disk 17 * 1 *, the trailing ^{elements 192, 193, 19 1} * must first be lifted off their cam tracks 189, 190, 191. For this purpose, the lever 259 (FIG. 32) is arranged pivotably on the axis 200, carries the pin 260, which extends downward between the cam tracks and trailing elements, and has the handle 26l.

FIGS. 29 to 32 show a modification of the sewing machine described above in FIGS. 2h to 28 insofar as it is a sewing machine with a device. which represent a manually operable mechanical memory 262 for predetermined fractions of the signals stored per stitch for the position of the needle 20, the feed regulator block 4l and the spring length of the brake spring 186.

An advantage of a sewing machine according to FIGS. 29 to 32 over a sewing machine according to FIG. 21 is that the Memory overhead for the automatic control of the needle thread brake device for the same number of selectable sewing tasks is smaller is because of the transition from the additive to the multiplicative selection principle. The independence of both storage, selection and Display devices - one for stitch patterns or stitching operations and the other for stitch pattern fields, respectively for types of material - from one another, but also leads-next to little Memory expenditure for optimal, automatic adjustments of the needle thread adenbreaskraft, provided that both memories the needle thread braking force control according to the invention.

909881/0370

The cam 180 is swiveled across the width of the stitch, and thus its cam path l8l _t with which the probe tip of the trailing element I96 cooperates by means of the spring 250, which is rotatably mounted on the axis 200. The follower member 196 is designed as a two-way lever, one arm of which carries the probe tip and the other arm is pivotably connected to the link 256 by means of a bracket 258 in order to move its probe tip along the sliding surface 255 of the follower link 195.

To replace a triple cam disk 17 ^, the trailing ^{elements 192, 193, 19 1} + must first be lifted off their cam tracks 189, 190, 191. For this purpose, the lever 259 (FIG. 52) is pivotably arranged on the axis 200, carries the pin 260, which extends downward between the cam tracks and trailing elements, and has the handle 26l.

Figures 29 to 32 show a modification of the sewing machine previously described in Figures Zh to 28 insofar as it is a sewing machine with a. Show devices that represent a manually operable mechanical memory 262 for predetermined fractions of the signals stored per stitch for the position of the needle 20, the feed regulator block kl and the spring length of the brake spring 186.

An advantage of a sewing machine according to FIGS. 29 to 32 over a sewing machine according to FIG. 21 is that the Memory overhead for the automatic control of the needle thread brake device for the same number of selectable sewing tasks is smaller is because of the transition from the additive to the multiplicative selection principle. The independence of both storage, selection and Display devices - the one for stitch patterns or Hähoperationen and the other for Stichciusterfeider respectively for types of material - from one another, but also leads-next to little Memory expenditure for optimal, automatic settings of the Na · ^ Delfadenbreaskraft, provided that both stores the needle thread braking force control according to the invention.

909881/0370

• · · «· ♦ II,

The manually pivotable cam disk package is rotatable on the bearing bush 170 and axially secured by locking disks 175 262 stored. It is made up of the from top to bottom Cam for the stitch field position 263, the cam for the Stitch field width 26 * f, the length of the cam for the brake spring

265 and from the cam for stitch length 266. The cams for the stitch field position have 263, the stitch field width 26 ^, the brake spring length 265 and the stitch length

266 has the same height as the corresponding cam disks 176, 181, 182, 187 of the sewing machine according to FIGS. 2k to 28, so that the same follower members 195, 196, 199 and their motion transmission members for needle 20 and feed control block kl are used. A change occurs with regard to the device for adjusting the Brensfederlänjje. Since it is also predetermined, like the setting of the other devices, the equilibrium lever 2 $ k is omitted and a double lever 267 takes the place of the double lever 2k6 , which with its probe tip 268 follows the cam for the brake spring length 265 and by means of a tab 2 ^ 5 is articulated to the handlebar 219.

The cam disk package 262 is pivoted by a gear drive. For the purpose, the cam disk package 262 has a gear wheel 269 which meshes with the pinion gear 270, which is arranged on a rotary handle 271, which is on the in the arm housing I ^ attached axis 272 is rotatably mounted. The twist grip extends in height beyond the pinion 270 and goes over into a film spool-like teeth 273 having Wreath 27 ^ »of an endless belt 275, e.g. made of plastic with the Tooth 273 corresponding openings drives which carries an indicator 276, which cooperates with the scale 277. The scale is divided into types of fabric and within a type of fabric again subdivided into 1 = light, m = medium, s = difficult. Corresponding are the locking grooves 278 of the hasty disc 278 of the cam disc

909881/0370

Benpaketes 262 arranged, into which the Hastldinke 279, mounted on the axis 201, engages after the action of the spring 279 '. Accordingly, the cams are respectively. Signal generator of the cam disks resp. Signal head rows .263, i $ k , 265, 266 arranged,

The scale field 277a of the scale 277 is provided aur setting of the cam disk package 262 to such sewing operations, the stitch pattern with "Satin stitches · ¹ require such as" buttonhole "or equivalent" stitching ". This means that the stitch length is not art these sewing operations on the fabric, Instead, it depends on the thread thickness of the needle thread, since with each lateral oscillation of the needle the workpiece is advanced by approximately the thread thickness so wide that the indicator can be adjusted to any desired position over the entire field width of the scale field 277a. The curve section of the cam disk 266 for the stitch length, which cooperates in this pivoting range of the cam disk package 262 with the probe tip of the follower element 199 for the stitch length, is inclined accordingly in order to be able to adjust the stitch length to different yarn thicknesses.

In the previous examples of mechanically controlled decorative stitch sewing machines According to the invention, a cam issued from the cam memory with each arm shaft rotation a swivel angle or a path signal for controlling a needle bar rocker and / or a feed regulator block and / or a needle thread braking element for setting a braking force.

In the following examples of electronically controlled decorative stitch sewing machines obtained according to the invention (Figures 33 to 38) a linear motor with every pulse - i.e. every revolution of the arm shaft - A voltage signal from the voltage memory, which the linear motor converts into a Wefj signal for controlling a loading bar rocker and / or a feed control block and /

909881/0370

T I t I

28 ·

or for setting a braking force of a needle thread brake element.

The decorative stitch sewing machine shown in Fig. 33 is provided with an adjusting device for forming a stitch pattern. the position of the needle and the workpiece to be sewn and a device for adjusting the length of the needle thread brake spring Each stitch is provided with a manual control device for setting any desired fraction of both the position of the needle set per stitch and the position of the workpiece to be sewn set for each stitch control means are also provided by both Manual control devices are influenced, and the brake spring for the needle thread automatically on a resulting Adjust braking force. All of these devices are built into the sewing machine described in FIGS. 3 to 8.

As shown in FIG. 33, a control pulse generator 28o is assigned to the arm shaft 283. According to Figure J> h , the pulses from the control pulse generator 280 are counted up in the binary counter 28l and addressed as address inputs to a stitch pattern memory 282, which is coded to generate an output with five bits as information for the position of the needle to an output with five bits as information for the position of the ,}. Workpiece and to have an output with five bits as 1 ,; Generate needle thread brake spring information. The information for the position of the needle is processed in a logic block 290, which can have a locking part through which the information for the position of the needle for later release of the servo device for the position of the needle at a correctly selected time for the operation of a device for setting the P position of the needle per stitch of a stitch pattern can be withheld Γι. In a corresponding manner, information for i; the position of the workpiece in a logic block 291 and brake spring ί; Information processed in a logic block 292. Each of these [> logic blocks 291 »292 can have a blocking part through which L ·

check the information | ^! i

909881/0370 I.

for the position of the workpiece respectively. the needle thread brake spring information BEZW for later release to the servo system for the position of the workpiece. to the brake spring servo system to one correctly selected point in time for the operation of a device - namely the setting of the position of the workpiece per stitch of a stitch pattern - resp. for the operation of the facility can be held back for each stitch of a stitch pattern to adjust the brake spring. Since the servo devices for the Position of the needle, the position of the workpiece and the length of the brake spring are identical to each other, with the exception of the special circuit described below for influencing the stitch field width, the stitch length and the brake spring length by hand, the description below applies to the servo system for the position of the Workpiece limited. Corresponding blocks in each system have the same reference number with the exception that the reference number for the components for the location of the needle per stitch with a Apostrophe and the components for the device for adjusting the brake spring length can be seen with zv / ei apostrophes.

The five bits of information for the position of the workpiece from logic block 291 are presented to a digital-to-analog converter 301. The outputs of converter 301 on the line are analog DC voltages that provide the required input for the position of the workpiece. The line 302 is via the potentiometer 288 described below with the Summing point 303 of a preamplifier 30 * »· with a low level connected, which forms the first stage of a servo amplifier system. The preamplifier 30 ** drives a power amplifier 305 »which direct current of reversible polarity to the electromechanical drive respectively. Linear motor 306 delivers whatever represents a reversible motor in the truest sense to the Position the drive in accordance with the analog input voltage on line 302. The amplifiers'

30 * f ", 305 t 305 t 305", are grouped in an integrated

909881/0370

CZ

30th

grated block 3 ^ 6 leashed together (Fig. 33).

A feedback position sensor 307 is mechanical with the reversing motor 306 and generates a feedback position signal on a line 3O8, which is characteristic of the existing starting position. The analog input voltage and the feedback signal are algebraically summed at summing point 303 to produce an error signal on line 309 to deliver. The feedback signal from the position sensor is also differentiated over time in a differentiator 310, and the resulting speed signal is applied on line 31I to a summing point 312 of the power amplifier 305 presented to the position signal at this point modify. The position sensor 307 can be any device which generates an analog voltage proportional to the position and can be a simple one in the embodiment described be a linear potentiometer, which is connected to a stable reference voltage and - effective as a voltage divider is. The differentiator 310 is preferably an operational amplifier connected to generate an output signal which equals the rate of change in the input voltage, as is known in the art.

The electronic control principle described so far is known also its use for setting the position of the needle and the workpiece per stitch of a stitch pattern (D.T-OS 250023 * 0. According to the invention, however, the application is new this control principle also for the automatic setting the needle thread brake spring per stitch of a stitch pattern as well as the automatic adjustment of the needle thread brake spring described in the following with manual adjustment of a Fraction of the signals stored per stitch for setting the position of the needle and / or the workpiece.

A potentiometer 288 'is connected to line 302',

909881/0370

31 ·

which as a resistor for the analog stitch field width voltage on line 302 acts to produce any desired fraction of that voltage on summing portion 303 and which in this way serves as an expedient means of reducing the size of the pattern. A button 353 can be found on the sewing machine for convenient actuation of the potentiometer 288 be arranged by the operator for lateral control of the stitch field width.

A potentiometer 288 is connected to the line 302, which acts as a resistor to the analog stub length voltage on line 302 by any desired fraction thereof To generate voltage at the summing point 303. A button is on the sewing machine to operate potentiometer 288 arranged for the operator to control the stitch length.

it ■. ■ '' «» 'η

In the line 302 iie potentiometers 289, 289 are one behind the other switched, which act as resistors for the analog voltage the needle thread brake spring length act to a fraction

Il

to generate this voltage at the summing point 303. That

ι _β ι

Potentiometer 289 is mechanically the same as potentiometer 288

,that,
coupled ,; if the resistance of the potentiometer 288 is increased when the button 353 is actuated - that is, the stitch field width is reduced - the resistance of the potentiometer 289 is reduced - that is, the braking force of the brake spring 89 (FIG. 8) is increased. The potentiometer 288 is mechanically coupled to the potentiometer 289 in such a way that if the resistance of the potentiometer 288 is increased when the button 351 is actuated - i.e. the stitch length is reduced - the resistance of the potentiometer 289 is also increased - i.e. the braking force of the brake spring 89 (Fig . 8) is decreased.

It can happen that the predetermined needle thread tensions do not match the programmed balance of thread tensions on the

909881/0370

■ I III '

Make knots from needle and bobbin thread. This can happen, for example, when the bobbin thread brake is set to several specific thread tensions is adjustable. In this case, the operator must turn the needle thread brake device to that of the set one Bobbin thread brakefcraft corresponding and marked area adjust so that the corresponding tension ratio of the two threads is established. To balance the equilibrium between the needle and bobbin thread tension at the knot both filaments is therefore in line 302 between the potentiometer 289 and the summing point 303 another potential

If

connected tiometer 288, which acts as a resistor for the analog tension of the needle thread brake spring to any

• ι desired fraction of this tension at the sealing point by pressing button 372. This potentiometer 288 is only used when using a needle thread brake device 90 (Fig. 7), which has no mechanical fractional setting, when using a needle thread brake device 3 to 5 with a mechanical fraction setting device

It

the 288 "potentiometer is not required.

The coding of the stitch pattern memory 282 can also take place in such a way that that no output with five bits is generated as needle thread brake spring information, so that only one output with five bits as information for the position of the needle and as information for the position of the workpiece. Then there is no need for a line 283, logic block 292, digital-to-analog converter 301. Instead, the potentiometer 289 is switched on via line 302 ″ the reference voltage of the energy source 3 ^ 7 connected.

In this way, the predetermined braking force becomes aa needle thread exclusively by manually setting the potentiometer for the stitch length and 288 * for the width of the stitch when actuated of buttons 351 and 353 are determined.

Due to the low setting speeds of the brake spring or 89 with manual operation of stitch field width and stitch length

909881/0370

the time differentiator 310, the line 311 · and the

H If

Summing point 312 of power amplifier 305 is omitted. In the figure J> h , the parts which are omitted if the coding of the stitch pattern memory 282 is carried out in such a way that no output with five bits is generated as needle thread brake spring information, are shown in dash-dotted lines.

According to FIG. 33, the linear motor 306 controls the feed regulator block * fl in that a motor swing arm 3? K is articulated by means of a link 373 to a swivel arm 125, which is arranged at one end of the feed regulator shaft 119, while the feed regulator block is arranged at the other end kl is attached . . '■.'. '

, I.

The linear motor 306 controls a needle bar rocker 22 by that a motor swing arm 375 is articulated to a needle bar pivot 22 by means of a link 376.

The linear motor 306 controls a brake spring 89 of a needle thread brake device 90 (Fig. 7) or a brake spring 186 of a needle thread brake device Fig. 3 to 5 in that a Motor swing arm 377 articulated with an angled lever 93 (Fig. 7) or lever 238 (FIG. 3) is connected by means of a link 378.

35 shows a perspective partial view of the sewing machine described with a possible arrangement of the rotary knobs: || for the manual adjustment of the stitch field width, 351 for the

Stitch length and 372 for the correction of the saved Pro-25 grammes for the balance between the thread tensions of the needle and bobbin thread at the knot of both threads. The partial view also shows a display and selection device, for example Stored stitch patterns, as they are from OS 2552565 got known. A selection key 379 is used therein to select a pattern group and the rotary knob 380 to select one Pattern within the selected pattern group.

909881/0370

• ti ··· I ··

till I ·· ·· ■ ··

3k

Another object of the invention is to provide a sewing machine to create that allows the stitch field width and / or the stitch length either to predetermined or to any set the desired fractions of the per-stitch settings for needle and workpiece, with each selection at the same time. tig the braking force of the braking spring of a needle thread braking device is automatically set.

In the above-described electronic control circuit of a sewing machine, there are therefore between the digital-to-analog converters according to FIG 301,301, 301 on the one hand and the summing points

303,303 *, 303 "of the preamplifiers 304, 304 ', 3O ⁴ M ^{1 of} the servo systems on the other hand either a manually operated switch 381 for predetermined settings of fractions or two manually operated potentiometer groups 382 and 383 for any desired settings of fractions switchable by means of handle 388. By means of a switch 384 having field effect transistors, which has three independent signal switches 384 a, 384 b, 384 c with two positions, by applying the correct voltage to the signal switches 3 ^ 4 a, 384 b, 384 c Actuation of a rotary knob 388 either the switch 381 for predetermined fractions or the two potentiometer groups 382, 383 for any desired fractions in the three circuits between the converter and summing points of the preamplifier.

If by actuating a rotary knob 388 in one of the positions a to h of the switch 38I for the manual setting of predetermined fractions. analog signals from the three converters 301, 301 *, 301 *, to lines 385, 386, 387, from the converters to the summing points 303, 303 », 303 lead, is connected by means of switch 384, then is one of the resistors of a series of resistors 391, 391 *, 391 ″ via contact rails 389 and contact slide 390 accordingly one of the selected switch positions a to h in each of the

909881 / 037Ö

• * ■ ■

three circuits connected and so the predetermined fraction the signals stored per stitch for setting the position the needle and the workpiece ■ and the

Brake spring force respectively. Brake spring length adjusted.

When the rotary knob 388 is switched to the "i" position of the switch 38I, the potentiometer groups 382, 383 are connected to the lines 392, 393 »39 ¹ N which lead from the three converters to the three summing points by means of the switch 38 ^; connected in the same way as in Fig. 3 ^ · If you therefore with a rotary knob 353 (Fig. 37) the potentiometer 288 * for the stitch field width and / and with a rotary knob 351 (Fig. 37) the potentiometer 288 for the stitch length of Hand adjusts to any desired value, then the potentiometers 289 and 289 adjust automatically due to their coupling with their associated group potentiometer and thus a resulting pulp spring force for the needle thread as described in Fig. 3 ^ a.

If the coding of the stitch pattern memory 282 takes place in such a way that no output with five bits is generated as information for the needle thread brake spring, then - just as described in the control circuit Fig. 3h - logic block 292, digital

It Il Il

Analog converter 301, time differentiator 310, line 311

Il Il

and jumming point 312 of power amplifier 305 · In 3O all the parts that are no longer required are shown in dash-dotted lines. Instead, the potentiometer 289 is connected to the reference voltage of the energy source 3 ^ 7 via the line 39 **.

Since the required needle thread tension - as described above - by the selected stitch pattern, by the selected The width of the stitch field and the selected stitch length are determined, which in turn are determined by the sewing operation and the type of fabric sewing machines with a control circuit according to Fig. 36, i.e. with independent stitching

909881/0370

Both a J

Selection and display device for sewing operations and their '

■ '■ γ - ■:

associated stitch patterns as well as with a selection and display device equip for types of fabric.

* An advantageous selection and display device for sewing opera_ functions and their associated stitch pattern is in) OS 2552565

described. Ss are only the stitch patterns corresponding to l

Arrange sewing operations in groups. The stitch pattern field memory;

rather with selection device was already described in Fig. 36- \ '■'? *

ben. Its display device, sorted by type of substance; <;. ·

as well as the display device for sewing operations and their related f \

related stitch patterns are shown in FIG. A per- |]

Perspective partial view of the sewing machine according to Fig. 36 shows f ^:

Fig. 37. It shows all the handles 379, 38O, 388 and 253, 't > selbsvtatxge

351, 353 »which help to determine the setting of the required needle thread tension. As a result, it is generally sufficient to operate the handles 379, 38O, 388 for the selection of the sewing operation, associated stitch pattern and type of fabric in order to automatically set the required needle thread tension. In special cases, for example if the programmed ratio of bobbin to needle thread tension needs to be corrected or if the operator ■ ' prefers the stitch field width and / or the stitch length t \

to be set individually, the hand lever 253 or the hand: ■ have to operate 351 »353. ,;

The setting of the stitch pattern fields to the positions 388 a,; „■

up to h, - i.e. on types of fabric - is in the stitch patterns for the ί: '

Sewing operations "sewing together", "stitching", "hemming" and '

"Plug" advantageous. Since in the positions 388 a to h '.

the stitch length of the stitch pattern field also changes in a predetermined manner, -,

must be used for "satin stitches", i.e. for stitch patterns where the (,)

The stitch length is roughly the same as the thread $ regardless of the type of fabric

Thickness is, for example, with the buttonhole or with many, only needle |

909881/0370

controlled decorative stitches, the servo system for the feed (303 to 312) by the potentiometer 288 via the line 393 can be influenced by one of the resistors 391 via the line 386. This point / corner becomes when a stitch pattern is selected with "Satin stitch" by operating a selection handle 379 or 38O (Fig, 37) the correct voltage to the signal switch 384 b created and thus the potentiometer 288 for the individual « Fractional setting of the branch length of the line instead of a resistor 391 of the line 386 switched on.

Therefore, if you press a corresponding selection handle 379 selects e.g. "Buttonhole", then the width of the buttonhole is adjusted by setting the type of fabric by pressing of the rotary knob 388 and thus moving a pointer is determined. The desired otich length, which is approximately the one used Yarn thickness is to be achieved by setting the pointer 397 of the rotary knob 351 in the area of point 395. The required needle thread tension is also set automatically in this case.

909881/0370

Claims (1)

2828Q83 Claims 1 · Sewing machine with an automatic by control means set needle thread braking device, marked by means of a bin direction that serves to create a stitch pattern 2 to adjust the position of the needle (^ 7 «59» 191 * 19A-; 282, 306; ' 22) and the one to be sewn Workpiece (38, * fl; 189, "192; 282, 306; 30) each Sting, by a manual control device to the desired one Fractional setting both of the per stitch set position of the needle (2 * f, 51, 77, 6l; I8I, 196, 256, 258; 288 ¹⁾ and the each stitch displaced position of au sewing workpiece (5 * ^»-; 6k, 117, ** 2, int 187, 199, 207, 215; 288), by control means (52, 55, 83, 86, 91; 289 ', 239; I85, I82, 25 ^, 2W, 2k5t 219) which are influenced by both manual control devices , and the one. preferably set as a spring (89, I86), the needle roller emselement automatically adjusts to a resulting braking force, by a bobbin thread brake spring (103) of a bobbin thread brake device which is set in a known manner to a certain braking force, this forming the basis of the design of the control means 2 ^ lies in order to balance the elasticity of the Bobbin thread and the tension of the needle thread at the knot from both threads in the fabric automatically to obtain. 2. Sewing machine according to claim 1, characterized by such a design of the control means that when enlarging the stitch field width the resulting braking force of the 90988 1/0370 ■ * * ♦ · ·. r ι 39 The spring (89-186) is reduced and that when it is enlarged the resulting braking force of the spring (89, 186) increases along the length of the stitch. 3. Sewing machine with a needle thread brake device automatically set by control means by means for setting the position of the needle (A-7, 59; 191. 19f? 282; 30 ^; 22) and the one to be sewn YJerkstückes (38, 4l; 189, 192; 2 $ 2, 3O6; 30) each Sting, by a hand-influenced stitch pattern field e memory (127, 16 '+, 262, 38l), each with one row of signal heads (130, 132; 264, 266, 265; 391 * ♦ 391, 391) for the predetermined setting of one Control device (153, ΐ46, Λ2, kl; 199, 207, 215; 306, 386, 389, 390) for the stitch length, from a control device (24, 6l, 77; 196, 256, 258; 306 ¹ , 385, 389 , 390) for the stitch field width and from a control device (267, 268, 245, 219; 306 ¹¹ , 387, 389, 390) for the needle thread spring (89, 186) (41) and needle thread brake spring (89, 186) ten, and ■■. ··· ■: by a bobbin thread brake spring (103) of a bobbin thread brake device which is set in a known manner to a certain braking force, this the design of the signal head series (131, 265, 391 ') for the needle thread brake spring (89, 186) 909881/0370 • · i · I ko the stitch pattern field memory (127, l6 * f, 262, 381) is based on the equilibrium of the Tension forces of the needle and bobbin thread * at the knot automatically obtained from both threads in the fabric " ^, Sewing machine according to claim 3, characterized in that a signal generator row (131) ^{predetermined the setting of the needle thread spring (89, 186) by signal transmission means (I 1} K), 91, 93) instead of a control device. 5, sewing machine with a needle thread brake device automatically set by control means, characterized by a memory (27 ¹ * »282) of the setting signals (191, 189, 190) for each stitch of a stitch pattern to devices for setting the position of the needle (19 ¹ *, 256 ; 301 * to 306 *, 376; 22) _(of the workpiece to be sewn (192, 206, 207; 301 to 306, 373; kl) and the length of the needle thread brake spring (193, 219; 30l "to 306», 378; I86 ) and by a bobbin thread brake spring (103) of a bobbin thread brake device , which is set in a known manner to a certain braking force, this being the design of the control means of the Memory is based on the equiv / icht the tension of the needle and bobbin thread at the knot from both threads in the fabric increases automatically obtain. 6. Sewing machine according to claim 3 or f * characterized, i by a memory for stitch patterns (! Oil), which emits setting signals for the position of the needle for each stitch of a stitch pattern, by such a dependent 909881/0370 kl capacity of the memory for stitch pattern fields (l64) from Memory for stitch patterns (l6l) that when selecting one Stitch rest of the stitch pattern memory (l6l) inevitably has several assigned to the selected stitch pattern (l6l) Stitch pattern fields (130, 132) and needle thread brake spring lengths (131) of a needle thread brake spring (89, I86) of the Stitch pattern field memory (164) are selectable. 7 »Sewing machine according to claim 3, characterized in that by means of a handle (13 * 0 trailing elements (60, 6l, 1 ^ 0, 1 ^ 6) and signal generator (I38) of the stitch pattern field memory (127) for the predetermined setting of the stitch field width and stitch field position , Stitch length and needle thread braking force disengaged and in their place for each type of setting follower elements (60, 6: i, 1 ^ 0, lk & and signal generator (139) for setting any desired setting using a handle (13 * l, _{IkB 1} 15 ¹ O take effect, 8. Sewing machine according to claims 1 and 3, characterized in that that a switching device (38 * 0 is provided which allows the stitch length and the stitch field width to be freely selected in one switching position and to be predetermined in the other switching position, whereby in both switch positions of the switching device (38 * 0 the spring force of the brake spring (89 / I86) for the needle thread is determined automatically by control means (381, 382, 383). 9 · Sewing machine with a bobbin thread brake device and ) with a device for automatic setting a needle thread braking device, characterized in that several setting devices (17 ^, 193, 219; _{185/182 Λ} 2 ^ 5, Zk6, 25k ', 220, 238, 2 * fO? 282, 292, 30l ", 38l _f 303 to 312) to compensate for several influences' 909881/0370 5 10. '- ■ * »· ■ ·· ··» Ii 42 2828083 several adjustment processes on the needle thread together, 'on a needle thread braking element (186) of the needle thread braking device (253) act to so the tension of the needle thread on the tension of the 10 Bobbin thread at the knot of both threads in the fabric place. Sewing machine according to Claim 9, characterized in that 11. both one or more setting devices (174, 193, 219ί 182, 185, 245, 246, 254; 282, 292, 30l " _t 38I, 303" I 15 to 312) for predeterminable influences on the Nadelfa den as well as one or more adjustment devices (220, 238, 240; 288) for non-predeterminable influences on the needle thread together on the braking element (186, 89) of the needle thread brake device (253 * 90) act. 20th Sewing machine according to Claim 9 or 10, characterized net that means for setting predeterminable Influences on the needle thread in particular an adjustment 12th device (Γ? 4, 193, 219; 282, 292, 30l ", 303" to Il
312) to compensate for the influences from the position setting 25th of needle and workpiece to be sewn per stitch and one Adjustment device (l82, 185, 254, 246, 245, 219; 38l) to compensate for the influences on the needle thread Fractional adjustments of the position adjustment of the needle 13th and include the workpiece to be sewn. ' 30th Sewing machine according to one of Claims 9 to 11, characterized characterized that a setting device (182, I85, 219i 245, 246, 254; 220, 238, 24θ; 288 * ', 381), the one ■. i Balances influence that is not based on a positional setting of needle and workpiece to be sewn per stitch is based on the The pulp force range of the needle thread braking device changes. Sewing machine according to Claim 12, characterized by a modular arrangement of an adjusting device 909881/0370 I. S. TZ (220, 238, 240) with a needle thread braking device I. (253 ^f ). _: lh. Sewing machine according to claim 12, characterized in that ί that a needle thread braking device (90, 253) i'ä 5 with in particular a brake spring (89, 186) ί is provided, ? ■ 'i that the length of the brake spring by means of an or J several setting directions (I82, 185; 289, I 289 ';265;38I; 17 ¹ M 282) automatically activated I 10 is J that an automatically adjusted spring length through a manually controlled device (219, 221, ■? 228, 238, 2 ^ 0; 288 ") to select fractions olai mJer i len a SignaliVcier setting deviceo (l82, 15 185; 289, 289 ¹ ; 265; .38I; 174; 282) influence is cash. ■ 15. Sewing machine according to claims 9 and 11, characterized in that that a memory for stitch patterns and needle thread braking forces (174, 282) and a memory for stitch 20 musterfeider and needle thread braking forces (262, 381) independent are selectable from each other, with both memory on the setting of needle (20), gate (4l) and Needle thread brake spring (89, I86) act. 16. Sewing machine for lockstitch with a bobbin thread 25 braking device and with an adjustment device for the automatic setting of a needle thread braking force, characterized, ■ \ that a needle thread brake device (90) with in particular I a special brake spring (89) is provided, fl 30 that the spring length of the brake spring by means of an or | ί, | several setting devices (127, I38, I60) :) is set automatically, 909881/0370 that a manually controlled device (3A8, 151 » 91 »1 ^ 0) to select any desired one Spring length is provided, that TTmschaltmittel (131 »13Ό either the Sinstelleinrichtung (127 »138, 160) for automatic one provided spring lengths or the manually controlled device (1 ^ 8, 151, 91, 1 * K)) for setting of spring lengths on the brake spring (89) and that a certain underlying the automatic brake control of the needle thread Braking force adjusted bobbin thread brake spring (103) is provided. 17. Sewing machine according to claim 1, characterized in that one of the stitch pattern formation serving device, two Manual control devices for setting the Woefdeh automatically adjust a resulting needle thread braking force, electrically controlled, 18. Sewing machine according to claim 3, characterized in that a device serving for stitch pattern formation and a manually influenced stitch pattern field memory be controlled electrically, i9. Sewing machine riäcn claim 5 thereby 'geke ^ naheiähöei »that a memory which outputs setting signals for each stitch of a stitch pattern, and means for setting the position of the needles of the workpiece to be sewn and the length of the needle thread brenis spring which these setting signals record, be controlled electrically. 20. Sewing machine according to claim 9, characterized in that 909881/0370 several adjustment devices that are common . on the braking element of the needle thread braking device act, be controlled electrically. 21. Sewing machine according to claim 17 or 18, characterized in that one of the stitch pattern formation is used electrically controlled device for controlling the position of the needle (282, 290, 301 *, 303 * to 312 *) and the to sewing work piece (282, 291, 301, 303 to 312) is provided per stitch, which has a pulse counter (281), Pattern memory (282), logic block (290, 291) digital-to-analog converter (301, 301) and means for forwarding (385, 386, 392, 393) t amplify (30 ^ ', 305 *, 30 ^, 305), move (3O6, 306), control (307, 307) and correct (303 *, 3io'bis 312 *, 303. 310 to 312). of voltage signals of the sample memory (282) included, and that voltage signals of an energy store (3 ^ 6) or a pattern store (282) for the Starting position of a reversing motor (306) for a needle thread braking element (I86) are influenced by electrically controlled means (38I; 382, 383) for automatic Fractional setting of a needle thread brake element (186). 909881/0370