CH698815B1 - A method for operating an embroidery machine with loop former and embroidery machine according to the procedure. - Google Patents

Abstract

A method for operating a shuttle embroidery machine with a plurality of embroidery sites, wherein at each embroidering embroidery needle thread (23) from a bobbin to the embroidery needle (22) leads, and a fabric carrying, slidably driven frame is arranged on a machine frame, on one side the embroidery tools with embroidery needles (22) and opposite the sliding in guideways boats (17) are arranged, each supplied from a reel back thread is guided in the stitch formation with the shuttle (17) through a loop (25) of the needle thread (23), which is unfolded by a return stroke of the embroidery needle (22), wherein during the looping of the needle thread (23) produced by the embroidery needle (22), a loop former (29) engages in the loop (25) produced, which engages the loop (25) for the needle Passage of the shuttle (17) is kept open, and that during the loop former in engagement with the loop ( 25), the embroidery needle (22) is withdrawn.

Description

The invention relates to a method for operating a shuttle embroidery machine with a loop former according to the preamble of patent claim 1.

In the operation of embroidery machines there is a need to operate embroidery machines at high speed in order to increase the production capacity. Currently, in embroidery machines speeds in the range of 400 to 600 revolutions per minute are common. If you want higher RPM ranges to boost your production output, you're at the limit of controlling oscillating masses. Especially with the large embroidery hoops on large embroidery machines, there is the problem that high mass acceleration forces have to be controlled at the aforementioned speeds. With regard to the hoop, correspondingly large-sized guide elements and the like must be provided. Such an embroidery frame usually has dimensions of about 20 m in length and 2 m in height with a weight of several hundred kilos. The movement of the hoop is only possible as long as the embroidery needle is out of engagement with the fabric to be embroidered. Only in this time window, when the embroidery needle is pulled out of the fabric to be embroidered and after a short time when it re-enters the fabric, it is possible to move the embroidery frame. This is done in a period of about 40 milliseconds, which are available to move the hoop to a new embroidery position. It is obvious that it is difficult to move such an embroidery frame to a new location in a time window of about 40 milliseconds.

Accordingly, there is a need to increase the time in which the hoop can be moved. If such an extension of the displacement time for the embroidery hoop, it would be possible, with the same masses and the same construction of the machine base frame, to operate the embroidery machine with higher numbers of revolutions, whereby the production capacity is significantly increased.

This means that on the one hand there is a desire to extend the time in which the needle is out of engagement with the substance, and on the other hand to shorten the time at which the needle is in the fabric to the needle thread a loop to form for the passage of the shuttle.

It is known that the needle with her - located at the top - Nadelöhr the loop of the needle thread so that the needle first passes through the fabric and then through the stitch hole in the needle plate, so - from the hoop seen - to form a loop on the side facing away from the fabric in the region of the guideway of the shuttle. This is done in the prior art, characterized in that when the needle has reached its maximum depth in the X direction (longitudinal axis of the needle), a short return stroke takes place and unfolds by this return stroke and the resulting friction of the needle thread in the needle eye a loop.

By this loop, the shuttle is pushed, initially the tip of the shuttle enters the loop, the loop expands, catching the needle thread from the thread store and then finally passes through the loop formed.

It is now important that during the entire passage time of the shuttle through the needle loop, the needle must be kept substantially at its advanced position in order to keep the loop permanently open. This is the critical time period during which the needle must remain in the fabric to allow looping and to wait for the shuttle to pass through this loop.

On the other hand, if it is possible to shorten the time in which the needle remains in the fabric, the shifting time of the embroidery frame could be extended. It is therefore the aim of the invention, the time in which the embroidery needle passes through the fabric and needed for the loop formation and the passage of the shuttle to shorten significantly. On the other hand, this would make it possible to substantially extend the time when the needle is outside the material.

The invention is therefore based on the object, a method for operating a shuttle embroidery machine and a shuttle embroidery machine, which operates according to the method, in such a way that the time at which the needle is out of engagement with the substance, extends to a considerable extent is.

To solve the problem, the method is characterized by the technical teaching of claim 1.

It is important that during the loop formation of the needle thread produced by the embroidery needle, a loop former engages in the generated loop, which keeps the loop for the passage of the shuttle open, and during this time during the loop former engaged with the loop formed is, the needle is already withdrawn.

The loop former according to the invention is therefore a separate part, which operates independently of the embroidery needle and detaches the embroidery needle in the loop formation, with the aim that the embroidery needle earlier - than otherwise - can withdraw from the fabric, because the loop former the role the embroidery needle in the formation (keeping open) of the loop partially takes over.

With the given technical teaching, there is the significant advantage that the embroidery needle is only initially used for the loop formation. The embroidery needle only briefly opens the loop during its return stroke and thus starts looping.

However, as soon as the loop due to the Rückhubphase the embroidery needle is opened, the loop former according to the invention is used. This engages in the loop and keeps the loop for the passage of the shuttle further open.

It is important that during the engagement of the loop former in the loop formed now the needle can be withdrawn immediately, because the needle eye at the top of the needle no longer for the entire duration of the loop formation - as known in the art - available must stand.

This makes it possible for the first time to withdraw the needle relatively early and out of engagement with the substance, because the loop former according to the invention keeps the loop open and allows the passage of the shuttle.

An essential feature of the method is that it dispenses with a double stroke of the needle and only a single stroke (namely, the return stroke described above) takes place.

The belonging to the prior art double stroke of the needle was required because first the needle had to pass through the fabric to open the loop on the first return stroke. The second stroke, which follows the return stroke, is required in the prior art to keep the loop open.

A significant advantage is now that the second stroke of the embroidery needle is eliminated. Instead, only one return stroke takes place, because the loop is no longer kept open by the further stroke following the return stroke, but rather by the novel loop former. Another stroke of the needle, which adjoins the return stroke, is thereby avoided.

Thus, it is now possible for the first time to bring the needle very quickly out of engagement with the substance, because the needle is just used for the simple return stroke for looping and all other strokes of the needle are no longer required. These are saved and the needle can already be pulled out of the fabric already, if the loop was initially formed by her. For the further continuation of the loop provides the loop former. Thus, the free time in which the needle is out of engagement with the substance, be significantly extended.

In a preferred embodiment of the invention, the loop-forming element is designed as a passive, spring-loaded retaining element. This spring-loaded retaining element keeps the loop open and takes over the function of the needle eye of the embroidery needle, as is known in the prior art. The term "spring-loaded retaining element" is also understood to mean that there is a simple wire bow which is able to engage with its bent end in the region of the loop, wherein it is important that the boat moves against this loop former and for movement control with this collides. The loop is thrown on the loop former, so to speak, which comes into contact with the loop, engages in it and keeps it open.

In a preferred first embodiment, it is provided that the loop former is therefore designed to be spring-loaded in order to be pushed out of the shuttle by the boat due to its spring force.

In another embodiment, it may be provided that the loop former is actively driven and is not herausverdrängt from the shuttle from the shuttle track, but is driven by an active control. Such control may e.g. an electromagnetic control or a pressure and / or suction air control.

In a third embodiment of the invention, it may be provided that the loop former is not designed as a mechanical holding element, but as an air nozzle, which is able to hold the loop at a certain time and release it at another time again.

In the above first embodiment, it was provided that the loop former is displaced from the shuttle in the direction of the needle longitudinal axis of the shuttle and in this case the spring force of the loop former is used to push back spring loaded in the shuttle track, when the shuttle the loop and has passed the loop former.

In another embodiment, however, it may be provided that the loop former instead of an axial movement parallel to the longitudinal axis of the needle now instead performs a perpendicular thereto moving pivotal movement.

In a third embodiment, it may be provided that the loop former performs a perpendicular to the needle longitudinal axis moving sliding or pivoting movement.

In the following, the invention will be explained in more detail with reference to several execution paths illustrative drawings. Here are from the drawings and their description further features essential to the invention and advantages of the invention.

In the drawings: <Tb> FIG. 1: <sep> Schemes the movement of the embroidery needle in the X-axis (plotted on the ordinate) in relation to the rotation angle of the embroidery machine on the abscissa. <Tb> FIG. 2: <sep> A partial perspective view in a first movement, when the needle has already formed the loop and the boat has not yet entered the area of the loop <Tb> FIG. 3: <sep> An enlarged view of FIG. 2 <Tb> FIG. 4: <sep> A progressive movement of the shuttle in comparison to FIG. 3 <Tb> FIG. 5: <sep> Another progressive movement of the shuttle compared to FIG. 4 <Tb> FIG. 6: <sep> Another progressive movement of the shuttle compared to FIG. 5 <Tb> FIG. 7: <sep> Another progressive movement of the shuttle compared to FIG. 6 <Tb> FIG. 8: <sep> Another progressive movement of the shuttle in comparison to FIG. 7 <Tb> FIG. 9: <sep> Another progressive movement of the shuttle compared to FIG. 8 <Tb> FIG. 10: <sep> The representation of the holder and attachment of the loop former to a guide plate <Tb> FIG. 11: <sep> An embodiment of a loop former modified with respect to FIG. 10 <Tb> FIG. 12: <sep> An embodiment of a loop former with a suction nozzle modified from FIGS. 10 and 11

1, the movement curve 1 of the needle is compared with a novel movement curve, the difference being in the curve branches 15 (invention) and 15 (prior art).

In particular, the movement curve 1 of the embroidery needle 22 is juxtaposed with the movement curve 2 of the shuttle.

On the ordinate, the movement of the embroidery needle 22 in the direction of the longitudinal axis (X-direction) of this embroidery needle is shown.

However, the boat 17 moves in the Y direction, as is apparent from the following drawings of FIGS. 2 to 10.

For example, in Fig. 2, the Y-axis is registered with respect to the shuttle 18.

At position 3, the embroidery needle 22 enters the fabric and moves on the Kurvenast up to position 4 in the X direction. In this case, the needle thread 23 (see FIGS. 2 and 3) has not yet formed a loop 25. At position 4, the return stroke of the needle, which ends at position 5, begins. This forms a loop, as shown in FIGS. 2 and 3, because a certain friction of the needle thread 23 takes place on the one hand in the needle eye 26 and the other on the needle hole 24 of the needle plate 20.

According to the prior art, at position 5 after completion of the return stroke of the embroidery needle 22, a further stroke of the embroidery needle 22 to position 6, just to keep the loop 25 open, which is avoided in the present invention. Beyond the position 6 on the Kurvenast 15 another hold open the loop, which is kept open until the needle comes out of engagement with the fabric at position 7.

With reference to the movement curve of the shuttle 2, this means that the shuttle at position 10 has the position according to FIGS. 2 and 3 and the shuttle tip 19 has not yet entered the area of the loop 25.

At position 11, the shuttle tip 19 enters the loop 25, as shown in Fig. 4.

The uppermost position of the shuttle at position 12 corresponds to Fig. 8 and the boat then makes a return stroke, which extends from position 12 to 13 position.

It is now important that a change in the movement curve of the needle 1 takes place at position 5. There it can be seen that after the loop formation of the loop 25 (at position 5) immediately the curve branch 15 is traversed. This is achieved by the use of loop former 29, so that the embroidery needle in the region of the curve branch 15 can already be brought out of engagement with the fabric at position 7. The embroidery needle can thus be withdrawn early.

This is shown by the comparison of the short period 16 (prior art) compared to the long period 16. The time period 16 in each case shows the time span in which the embroidery needle is not in engagement with the material and in the region of which the embroidery frame can be moved.

The time period 16 shows the period of time according to the prior art, which results from the fact that at position 7, the needle comes out of engagement with the substance and at position 9, the needle enters the fabric again. From this it can be seen that the period of time 16 according to the prior art is very short and therefore there is little time available to move the hoop to a different position.

At the same time, the advantage of the invention is shown, because now the period 16 can be extended to the period 16, because just at position 7, the needle can be pulled out of engagement with the fabric and remains out of engagement until the Needle at position 9 re-enters the fabric.

In the end, therefore, the position 7 of FIG. 1 in the direction of arrow 14 is shifted to the left, so as to achieve an extension of the period 16 in the direction of the longer period of time 16.

The position 8 should be mentioned only for the sake of completeness, it is a position in which the needle tip 27 is furthest away from the fabric. In the drawings, the substance itself is not specified, but only a fabric plant level 21 at the back of the needle plate 20, where the fabric is applied.

The fabric line (fabric plane) extends in the diagram in FIG. 1 as a horizontal line from position 3 to position 9.

Figs. 2 and 3 show the finished loop 25 at position 5 in Fig. 1und according to the invention, the loop former 29 is now put into use, which is formed in the embodiment of FIGS. 2 to 11 as a resilient wire hanger.

The loop former 29 is a multi-bent wire hanger, which forms a bow 28 forming a bent tip, which is described in greater detail in FIG. 10.

The bracket 28 is the actual element which distinguishes the loop former 29 and which is able to keep the loop 25 open during the return stroke of the embroidery needle 22. This will be explained with reference to FIG. 4näher.

Once the boat 17 is pushed further on the shuttle track 18 in the direction of the coordinate Y, the shuttle tip 19 moves up and enters the area of the loop 25. The bracket 28 of the loop former 29 is not yet engaged with the Loop 25. It is now important that the loop 25 impinges on the rounded circumference of the shuttle and is moved in the direction of arrow 44 upwards. Thereby, the loop 25 is brought into the engagement region of the bracket 28, as shown in Fig. 6.

Now, the loop former 29 with its bracket 28 assumes the function of keeping open the loop 25, as shown in Fig. 6. At this stage, the embroidery needle 22 can now be withdrawn, at the same time the outer circumference of the shuttle 17, the bracket 28 displaced in the direction of arrow 45 to the left against the spring force of the bracket. As a result, two opposite movements take place on the same axis.

On the one hand, the embroidery needle 22 is retracted in the opposite direction to the arrow 45 and at the same time the bracket 28 is displaced in the direction of arrow 45 to the left in the direction of the needle longitudinal axis of the shuttle. This results in the value of the present invention, because the bracket 28 now holds the loop 25 open during the further movement of the shuttle 17, as shown in Fig. 7. Here it can be seen that the embroidery needle 22 is just out of engagement with the fabric in the area of the fabric plant level 21 of the embroidery plate 22, while in Fig. 8 is shown a complete detachment from the fabric.

Here it can be seen that the bracket 28 of the loop former 29 holds the loop 25 open, although the needle itself is already out of engagement with the substance. This is the Schiffchenstellung in position 12 of FIG. 1 and at the same time it is seen that the needle thread 23 from the bracket 28 falls because he comes loose and is no longer under tension after the shuttle has passed the loop 25.

The boat is thus - as shown - in position 12 and the needle thread 23 automatically slides down from the bracket 28.

It is relatively indifferent how the bent ends of the bracket 28 are formed. In the embodiment shown, the two legs 28a, 28b are arranged relatively parallel to one another and connected to each other by a common U-shaped piece 28c.

However, it may also be provided that the U-shaped connector 28c is formed as a tip or completely eliminated.

Referring to Fig. 9, a new cycle of motion follows, followed by the movement of Figs. 2 and 3. It is not shown that the shuttle is returned from position 12 back to position 13 and during this time the frame is moved, wherein at position 9, the needle for the next stitch formation again enters the fabric in the area of the fabric plant level 21. This is followed by the process as illustrated in FIGS. 2 and 3.

In Fig. 10, the attachment of the loop former 29 is drawn on a guide plate 38 as an exemplary embodiment. The guide plate 38 is in this case part of the shuttle guide and essentially consists of a plate-shaped element which has a projecting guide wall 40 on its front side.

The loop former 29 is arranged on this side and beyond the guide wall 40. It consists essentially of the aforementioned bracket 28, to which a straight obliquely upwardly extending leg 30 connects, which merges via a bend in a perpendicular thereto extending leg 31.

This leg 31 engages in a slot 32 in the region of the guide wall 40 and is guided there along a longitudinally displaceable. The bracket 28 makes due to the displacement by the shuttle a kind of rotational movement and therefore the slot 32 is provided, which is directed approximately parallel to the shuttle track and the longitudinal guide of this leg is used in the Y direction.

On the other side of the bracket 28 is followed by a substantially horizontal leg 33, which merges via a vertical bend in a leg 34, which in turn merges via a bend 35 in a spring leg 36 of relatively large length, at its upper free end in a holder 37 is non-rotatably clamped to the guide plate 38.

The bracket 28 thus performs in the aforementioned embodiment according to FIGS. 2 to 10 a spring-loaded displacement movement in the direction of arrow 45.

Instead of the loop former 29 now form as a leg spring, as shown in Fig. 10, it is provided in another embodiment, the trained as a leg spring loop formers now form a linear motion element.

In this non-illustrated exemplary embodiment, the bracket 28 is received in a longitudinal guide which is parallel to the needle longitudinal axis (X direction) of the embroidery needle 22 and in the region of this movement path in the direction of arrow 45 then a corresponding compression spring (eg a helical compression spring) is arranged ,

As a further embodiment, Fig. 10 also shows that the bracket 28 can perform a pivoting movement in the direction of arrow 46 about a horizontal axis, which is parallel to the Schiffchenbahn 18.

This spring-loaded pivoting movement in the direction of arrow 46 also causes either the bracket 28 is engageable with the loop 25 and out of engagement with the loop 25 can be brought.

11 shows a further embodiment of a loop former 42 which is supported from below via a vertical spring leg 36 and in principle has the same movement pattern, as shown in Fig. 10. It can be designed to be displaceable or pivotable both in the direction of arrow 45 and in the opposite direction. Likewise, it can be pivoted spring-loaded in the direction of arrow 46.

Fig. 12 shows a further variant of the arrangement of a suction nozzle 41, which is arranged with its nozzle mouth 43 above the loop 25, namely at the entrance of the loop into the eye of the needle 26.

Here, there may be various embodiments for the arrangement of such a suction nozzle 41.

In a first embodiment it can be provided that the suction nozzle is arranged immovably in the position shown in FIG. 12.

In another embodiment, it may be provided that the suction nozzle 41 is associated with an active movement drive, which selectively brings the suction nozzle into engagement with the loop end above the needle eye 26 in the position shown in FIG. 12 or disengaged.

Likewise, it may be provided that the suction nozzle has a pivot drive instead of a linear motion drive.

Incidentally, all the aforementioned movement and part-turn drives also apply to the mechanical loop formers 29 and 42, as illustrated with reference to FIGS. 10 and 11.

Advantage of the inventive teaching is that now the time period for the material movement of the relatively short period of time 16 was extended to an approximately half extended period of time 16 (about 150%), making it now possible for the first time, this time from 40 milliseconds to about 60 to 70 milliseconds and to ensure equal loading of the hoop and machine frame at higher engine speeds.

drawing Legend

[0075] <tb> 1. <sep> motion curve (needle) <tb> 2. <sep> Movement curve (shuttle) <Tb> 3 <sep> Position <tb> 4. <sep> position (start loop) <tb> 5. <sep> position (end of loop) <tb> 6. <sep> Position (2nd low) <tb> 7. <sep> position (needle exit) 7 <tb> 8. <sep> position (needle free) <tb> 9. <sep> position (needle entry) <tb> 10. <sep> position (boat Fig. 2-3) <tb> 11. <sep> position (boat in loop) <tb> 12. <sep> position (boat Fig. 8) <tb> 13. <sep> position (shuttle return stroke) <Tb> 14 <sep> arrow <Tb> 15 <sep> curve branch <tb> 15. <sep> Curve branch of the modified needle curve <tb> 16. <sep> Time span for material movement 16 <Tb> 17 <sep> boat <Tb> 18 <sep> shuttle race <Tb> 19 <sep> Schiffchenspitze <Tb> 20 <sep> needle plate <Tb> 21 <sep> Fuel System Level <Tb> 22 <sep> embroidery needle <Tb> 23 <sep> needle thread <Tb> 24 <sep> tap hole <Tb> 25 <sep> loop <Tb> 26 <sep> bottleneck <Tb> 27 <sep> needlepoint <tb> 28. <sep> Brackets 28a, 28b, 28c <Tb> 29 <sep> loop former <Tb> 30 <sep> leg <Tb> 31 <sep> leg <Tb> 32 <sep> slot <tb> 33. <sep> horizontal thigh <Tb> 34 <sep> leg <Tb> 35 <sep> turn <Tb> 36 <sep> spring leg <Tb> 37 <sep> bracket <Tb> 38 <sep> guide plate <Tb> 39 <sep> arrow <Tb> 40 <sep> guide wall <Tb> 41 <sep> suction nozzle <Tb> 42 <sep> loop former <Tb> 43 <sep> nozzle orifice <Tb> 44 <sep> arrow <Tb> 45 <sep> arrow <Tb> 46 <sep> arrow

Claims (13)

1. A method for operating a shuttle embroidery machine with a plurality of embroidery sites, wherein at each embroidering embroidery needle thread (23) from a bobbin to the embroidery needle (22) leads, and a fabric carrying, slidably driven frame is arranged on a machine frame, on the one side of the embroidery tools with embroidery needles (22) and opposite the slidable in guideways boats (17) are arranged, each supplied from a reel back thread in the stitch formation with the shuttle (17) through a loop (25) of the needle thread (23) out is, which is unfolded by a return stroke of the embroidery needle (22), characterized in that during the looping of the needle thread (23) produced by the embroidery needle (22) engages a loop former (29, 41, 42) in the generated loop (25) which holds the loop (25) open for the passage of the shuttle (17), and that during the loop-former in Eng Reef with the loop formed (25), the embroidery needle (22) is withdrawn. 2. The method according to claim 1, characterized in that the loop former (29, 41, 42) as a separate part of the loop (25) of the needle thread (23) of the embroidery needle (22) and the embroidery needle (22) after the loop formation by the loop former (29, 41, 42) is detached until the shuttle (17) has passed the loop (25). 3. The method according to claim 1 or 2, characterized in that the embroidery needle (22) only initially performs the loop formation and then the loop former (29, 41, 42) engages in the loop (25) and the loop for the passage of the shuttle open holds. 4. The method according to any one of claims 1 to 3, characterized in that the loop former (29, 41, 42) is displaced in the direction of the needle longitudinal axis of the shuttle from the shuttle track and the loop former moves back into the shuttle track when the shuttle passes the loop Has. 5. The method according to any one of claims 1 to 4, characterized in that the loop (25) impinges on the rounded circumference of the shuttle (17) and thereby in the engagement region of the loop former (29) belonging bracket (28) is brought. 6. The method according to claim 5, characterized in that on the one hand the embroidery needle (22) is withdrawn and at the same time the bracket (28) of the loop former (29) is displaced in the opposite direction to the needle longitudinal axis of the boat (17). 7. shuttle embroidery machine with a plurality of embroidery points, wherein at each embroidering embroidery needle thread (23) from a bobbin for embroidery needle (22) leads, and a fabric carrying, displaceable driven frame is arranged on a machine frame, on one side of the embroidery tools with embroidery needles (22) and oppositely slidable in guideways boats (17) are arranged, each supplied from a reel back thread is guided in the stitch formation with the shuttle (17) by a loop (25) of the needle thread (23) through A return stroke of the embroidery needle (22) is unfolded for carrying out the method according to one of claims 1 to 6, characterized in that a loop former (29, 41, 42) is arranged on the shuttle side, 8. shuttle embroidery machine according to claim 7, characterized in that the loop former (29, 42) is designed as a passive, spring-loaded retaining element. 9. shuttle embroidery machine according to one of claims 7 to 8, characterized in that the loop former (29, 41, 42) in the movement path of the shuttle (17) is arranged and is moved by this. 10. shuttle embroidery machine according to claim 7, characterized in that the loop former (29, 41, 42) is actively driven. 11. Schiffchenstickmaschine according to claim 7, characterized in that the loop former is designed as a suction nozzle (41). 12. shuttle embroidery machine according to one of claims 7 to 11, characterized in that the loop former (29, 41, 42) is designed to be displaceable or pivotable perpendicular to the trajectory of the shuttle. 13. Schiffchenstickmaschine according to any one of claims 7 to 10 or claim 12, characterized in that the loop former (29, 42) is a multi-bent wire hanger, which forms a bent tip forming bracket 28, which is suitable for engagement in the loop ,