EP0768418B1 - Embroidering machine, particularly of the Schiffli type, with a severing- and clamping device for the front yarn - Google Patents

Abstract

An embroidery machine, esp. a Schiffli machine, has a cutter and clamp for each needle thread. A blade (17) is rigidly attached to each fabric presser and works with a movable blade (21) and a yarn clamp (27). The blade (21) is constructed as a yarn catcher. There is a further yarn catcher (25) at some distance from the blade (21) and a clamp (27) is fitted between the blade (21) and the further yarn catcher (25).

Description

The present invention relates to an embroidery machine, especially Schifflistickmaschine, with a Front thread cutting and clamping device with one for each The front thread to be cut is arranged firmly on the presser Edge, a knife that can move against this edge and a thread clamp for clamping the front thread.

In DE-A-226 828 a device for facilitating the Cutting the front threads described, at which tight Holding devices arranged on the embroidery surface are that they run from the needles to the fabric Front threads are able to hold on when these threads are cut should be. The holding effect is achieved by forks or Clamping lever conveys which in relation to the Presser forks are movable. The front threads are then between the presser forks and the other forks recorded on which the threads can be cut. The needle-side thread ends are then held until the Embroidery needles are operated again for embroidering. The cutting the threads can either be done by a knife with which one person walks along the machine and continues the threads that cut the knife, or cut it is a rotatable clamping lever with each presser fork provided that when it rotates against a knife edge the presser fork is guided around the thread at the same time to cut and hold the thread end. The clamping and Cutting device, which has an individually rotatable lever required for each of the many embroidery sites, but is complicated and expensive and does not have the required length Lifetime and reliability in operation. This is true also for the thread clamping and cutting device according to the CH-A-683 785 to. This device is not for cutting of the front thread, but for cutting the back or Schifflifadens. It therefore belongs to a genus other than the present invention. Furthermore, the facility according to CH-A-683 785 a pivotable angular Entry and cutting element for the rear or shuttle thread on. The same type of cutting and clamping device with angular entry and cutting element for the rear thread can also be found in the subject of EP 0 666 352. There but for the front thread no use of such Mechanism made. Rather, one is for the front thread completely different, that in the area of needle and drill prevailing operating and space conditions Mechanism provided, as it was earlier through the EP-A-0 606 585 has been proposed.

EP-A-0 606 585 relates to one of the latest proposals for a cutting and clamping device for the front yarn one Embroidery machine. This device has a mounting rail for Cutting and clamping elements. Such a cutting and Clamping element consists of a fixed knife, which is attached to the mounting rail with retaining bolts. Over a Parallel guidance, which consists of hollow rivets, is on fixed knife a movable knife longitudinally displaceable guided. There is also a clamping spring on the fixed knife attached. The clamp spring has the additional task of play between the movable knife and the fixed knife avoid. To operate this cutting and clamping device, a complicated control mechanism is necessary. This must Carry out complicated movements in different directions. The facility is further complicated by the fact that a Selection mechanism for working and non-working Embroidery is provided. To open the knife in front of the A sliding piece must be moved. Further is a parallelogram-like shift of all cutting and Clamping elements with a swiveling movement necessary. About that there is also a movement towards the material plane required.

The object of the present invention is an embroidery machine to improve the genus mentioned at the beginning in such a way that with perfect and reliable cutting with little effort and clamping the front threads of the embroidery machine guaranteed becomes.

Starting from the prior art according to DE-A-226 828 this achieved according to the invention in that the knife as Thread catcher is formed at a distance from the knife another thread catcher is provided, and that the Thread clamp between the knife and the other thread catcher is arranged.

This training does not require individually rotatable levers or cutting elements and therefore has space in a small space. Also can have a large number of knives on one piece of sheet metal be trained. The mapping according to the invention allows simple way to grasp the front thread safely, reliably clamp and cut. This prevents jumping threads and later embroidering is possible. In contrast to State of the art, the front thread is on each other opposite sides of the thread clamp gripped and secure introduced into this. In contrast to the prior art takes place also no change of direction of the front thread when clamping instead of. This also contributes to secure clamping.

In the commercial Schifflistickmaschinen are in the Adjust the presser on a swivel around an axis Presser ruler arranged. According to an embodiment The invention is now the knife and the other thread catchers attached to a knife ruler, and the drive of the Knife rulers are made using at least one lever, one of which End is hinged to the knife ruler and the other end Has a joint on which an actuating lever engages, after cutting the threads the pivot point of the joint lies on the axis of rotation of a hinge around which the Presser ruler is pivoted during embroidery. With this Training will result in unnecessary wear of the knife edges avoided simple means. It should be noted that actuated over 200 times per minute when embroidering the presser becomes. In contrast, cutting takes place only in longer ones Intervals. Since in the training described Embroidery machine a relative movement of the knife edges when Avoiding embroidery will have a long lifespan Knife cutting guaranteed.

An advantageous embodiment of the embroidery machine provides that at least two actuating levers by one articulated to them Rod are interconnected. This will make it a safe one Parallel guidance of the knife ruler guaranteed. The Operating levers are advantageously designed as angle levers.

The clamping gap of the thread clamp is advantageously practically in on the same level as the thread to be cut. This extends from the needle to the embroidery floor before cutting. The clamping gap can be practically perpendicular to the surface of the the presser forming sheet metal piece and practical in the same direction as the movement of the movable knife in Cutting the thread run. In other words, that the clamping gap is arranged practically in the same plane is like the thread running from the needle to the embroidery base and that the direction of movement of the knife is practically rectangular is a thread. In contrast to the prior art, the Clamping the thread does not deflect it.

The thread clamp advantageously has a recess for guidance of the knife. The knife is between the Fabric presser plate and the thread clamp securely guided.

The thread clamp advantageously has a stationary part and a moving or resilient part. He sets it up own organ. In contrast to the state of the art not the presser or the knife part of the thread clamp. Since it represents its own organ, it can be used if necessary be replaced independently of other organs. The thread clamp advantageously has teeth on one of the two the surfaces forming the clamping gap. This makes a high one Reliability of thread clamping guaranteed. The teeth are arranged on the knife side and advantageously grip on the side Clamping gap in a recess. This has turned out to be special proven advantageous. The thread clamp is there expediently made of plastic. This allows one particularly cost-effective production of thread clamps with optimal Clamping properties. For example, the stationary part Be U-shaped, with the resilient part between the legs of the U is arranged. The resilient part can also have curved plastic spring, which is a special favorable thread clamping allows.

The plastic spring expediently acts after insertion of the resilient part in the stationary part with a predetermined force against the opening of the clamping gap. This there is no need for adjustment.

A stop can be provided to guide the way limited by which the clamping gap can be opened. In order to prevents e.g. the threading tool when threading is accidentally inserted into the nip and the Thread clamp damaged.

Fig.1

eine perspektivische Darstellung eines Ausführungsbeispiels der erfindungsgemässen Vorderfadenschneidund -klemmeinrichtung, wobei im linken Teil der Figur die Stellung der Messer und der weiteren Fadenfänger vor dem Schneiden der Fäden dargestellt ist, während auf der rechten Seite die Stellung nach dem Schneiden und Festklemmen der Fäden dargestellt ist, die Fäden selbst aber nicht eingezeichnet sind,

Fig.2

eine Ansicht der Einrichtung von Figur 1 von hinten gesehen,

Fig.3

die Einrichtung von Figur 2 im Schnitt,

Fig.4

die Ansicht des federnden Teils des Fadenklemmers,

Fig.5

den federnden Teil von Figur 4 von oben gesehen,

Fig.6

den stationären Teil des Fadenklemmers,

Fig.7

den stationären Teil von Fig. 6 von oben her betrachtet,

Fig.8

den Fadenklemmer bestehend aus stationärem Teil und federndem Teil,

Fig.9

den am Stoffdrückerblech befestigten Fadenklemmer mit dem Fadenfänger und dem beweglichen Messer in der oberen Stellung bereit zum Einziehen des Fadens, und

Fig.10

die Ansicht des Zusammenbaus von Fig.9 von oben gesehen.

The invention will now be described with reference to the drawing. It shows:

Fig. 1

2 shows a perspective view of an embodiment of the front thread cutting and clamping device according to the invention, the position of the knives and the further thread catchers before cutting the threads being shown in the left part of the figure, while the position after cutting and clamping the threads is shown on the right side, the threads themselves are not shown,

Fig. 2

2 shows a view of the device of FIG. 1 from behind,

Fig. 3

the device of Figure 2 in section,

Fig. 4

the view of the resilient part of the thread clamp,

Fig. 5

the resilient part of Figure 4 seen from above,

Fig. 6

the stationary part of the thread clamp,

Fig. 7

the stationary part of FIG. 6 viewed from above,

Fig. 8

the thread clamp consisting of a stationary part and a resilient part,

Fig. 9

the thread clamp attached to the presser plate with the thread catcher and the movable knife in the upper position ready to pull in the thread, and

Fig. 10

the view of the assembly of Figure 9 seen from above.

The perspective view of the front thread cutting and clamping device of Figure 1 shows the one Presser ruler 11 (Fig. 3) attached presser plates 13 with the presser fingers 15. At the lower part of the A presser finger 15 has a cutting edge 17. At Each presser finger 15 is a movable knife 19 arranged. A large number of such knives 19 can be on one Sheet metal piece 20 may be formed. Each knife 19 has one hook-shaped part 21, which acts on the one hand as a thread catcher and on the other hand, has a cutting edge 22 which is connected to the cutting edge 17 works together like scissors. The sheet metal pieces 20 with the Knives 19 are carried by the knife ruler 23. Also on Knife rulers 23 are thread catchers 25 with angled edges 26 arranged. It should now be noted that the hook-shaped Parts 21 of the knives 19 work as thread catchers, so that in this description, the thread catcher 25 as a further thread catcher denotes meaning. Thread clamps 27 are on the presser plate 13 attached, which will be described in detail later. It it should be noted that with each thread clamp 27 the knife 19 on one and the other thread catcher 25 on the other Come to lie so that the thread at the Downward movement of the knife ruler 23 from the hook-shaped part 21 and the further thread catcher 25 securely in the clamping gap 29 of the Thread clamp 27 is pulled, while at the same time through the Cooperation of cutting edge 17 and that on hook-shaped part 21 trained cutting edge 22 of the thread is cut.

In Fig.1 are also a needle plunger 26 with a needle 28 and a drill plunger 30 with a drill 32 as shown are provided for each embroidery site. It can be seen that in the described formation of the front thread and Clamping device is not in the way of the drill 32.

From Figures 2 and 3 are now further details of Front thread cutting and clamping device can be seen. The Device will be in position after cutting the thread shown. The knife ruler 23 with the also as Thread catcher acting knife 19 and the further thread catcher 25 is in the lower position. The presser 13 is in the position in which the presser finger 15 on the embroidery base 31, that is the fabric web.

On the knife ruler 23 there are pins at intervals arranged, which guide the knife ruler 23. One of the cones 33 can be seen in FIG. 3. This pin 33 is in one Bush 35 of the presser ruler 11 slidably mounted. The The presser ruler 11 is about an axis 37 of the ball joints 39 (only a ball joint 39 is shown) pivotable. With reference number 41 denotes the rod which is used for The presser mechanism of an embroidery machine is one of them. The drive the presser represents known prior art.

The knife ruler 23 is made up of two pairs of levers 47, 51 (only one is shown) worn. The drive of the knife ruler 23 serves the drive unit 43, e.g. a hydraulic cylinder, which engages the arm 45 of the angle lever 47. The arm 49 is articulated on the lever 51 via the ball joint 39. About the joint 53, the lever 51 is coupled to the knife ruler 23.

The parallel guidance of the knife ruler 23 is by the Lever pairs 47.51 (only one is shown) ensures the angle lever 47 coupled to each other via a rod 55 are. Now is an advantage if after cutting the threads the fulcrum 40 lies on the axis of rotation 37. This will make one Movement of the lever 51 when pivoting the presser fingers 15 avoided about the axis 37. This in turn prevents one Relative movement between the movable knives 19 and Cut 17, which could lead to premature wear.

As FIGS. 4 to 10, in particular FIG. 8, show, there is the thread clamp 27, for example, from a stationary part 61 and a resilient part 63. When assembled a screw 65 holds the parts 61 and 63 together. A Screw hole 67 is for fastening the thread clamp 27 with the screw 72 (Fig. 9) on the presser plate 13. A pin 68 engaging in the bore 70 acts as Protection against rotation. As in particular from FIGS. 1 and 8 can be seen, the thread clamp 27 has a clamping gap 29 which is practically perpendicular to the surface of the Presser plate 13 and in the same direction as that Movement of the movable knife 19 when cutting the thread runs. The thread clamp 27 has the knife side at one Clamping gap 29 forming teeth 69. In the shown The exemplary embodiment has teeth 69 on the side of the clamping gap 29 arranged and can in a recess 71 (Fig.5) of engage resilient part 63. The guidance of the knife 19 is used the recess 77. The stationary part 61 is U-shaped. The resilient part 63 is between the legs of the U. arranged. The spring action is provided on part 63 formed arcuate plastic spring 73. A stop 75 limits the opening of the clamping gap 29. To an exact To ensure positioning of the resilient part 63 is on stationary part 61 a wedge-shaped recess 76 is provided, into which a projection 78 of the resilient part 63 fits.

The embroidery machine is in normal operation Device in the position shown in Figures 2 and 3, wherein but the presser finger 15 after each stitch about the axis 37 (Fig.3) pivoted counterclockwise and from Embroidery base 31 can be lifted off. Now the thread should be cut the presser is again in the in Figure 3 location shown. Be by the drive unit 43 then the levers 47, 51 and thus also the knife ruler 23 operated. The knife ruler 23 is therefore up in the in Figure 1 shifted position shown on the left. The angled edge 26 further presses Thread catcher 25 between the embroidery base 31 and the needle 28 tensioned thread 74 (Fig.10) slightly to the side, whereupon the thread 74 springs back into the original position. In the subsequent downward movement of the knife ruler 23 is the Thread 74 both from the movable knife 19 and from the other Thread catcher 25 is gripped and pulled into the clamping gap 29 and finally by the interaction of the cutting edge 22 on hook-shaped part 21 and the cutting edge 17 (Fig.1) cut. The cutting is done like with scissors. The thread end remains clamped in the thread clamp 27, so that subsequently can be easily sewn on.

In summary, the following can be stated:

The embroidery machine has a pivotable about the axis 37 Presser ruler 11 with the presser fingers 15. On a cutting edge 17 is formed on the presser fingers 15. A knife ruler 23 is on the presser ruler 11 arranged, from the position shown upwards can be moved. On the knife ruler 23 are both Knives 21, which also serve as thread catchers and others Thread catcher 25 arranged. Between a knife 21 and a Thread catcher 25 is located on the presser plate 13 attached thread clamp 27. Now thread 74 should be cut the knife ruler 23 is moved up and again brought into the drawn position. The will Thread 74 from knife 19 running parallel to clamping gap 29 and captured by the thread catcher 25 and down into the nip 29 of the thread clamp 27 pulled. By interaction of Knife 19 and cutting edge 17 becomes the thread 74 as with a Cut scissors.

Claims (15)

1. An embroidering machine, particularly a Schiffli embroidering machine, comprising a front-thread cutting and gripping device comprising a cutting edge (17) fastened to the presser foot (13) for each front thread to be cut, a knife (21) movable against the cutting edge (17) and a thread gripper (27) for gripping the front thread, characterised in that the knife (21) is in the form of a thread catcher, an additional thread catcher is provided at a distance from the knife (21), and in that the thread gripper (27) is disposed between the knife (21) and the additional thread catcher (25).
2. An embroidering machine according to claim 1, wherein the presser foot (15) is disposed on a rule (23) pivotable around an axis (37), characterised in that the knives (21) and the additional thread catchers (25) are fastened on a knife rule (23) disposed on the presser-foot rule (11), and in that the knife rule (23) is driven via at least one lever (51), one end of which is pivoted to the knife rule (23) and the other end of which has a joint (39) engaging an actuating lever (47), and after the thread has been cut the centre of rotation (40) of the joint (39) lies on the axis (37) around which the presser-foot rule (11) is pivoted during embroidering.
3. An embroidering machine according to claim 2, characterised in that at least two actuating levers (47) are interconnected by a rod (55) pivoted to them.
4. An embroidering machine according to claim 2 or 3, characterised in that the or each actuating lever (47) is an angle lever.
5. An embroidering machine according to any of claims 1 to 4, characterised in that the nip (29) of the thread gripper (27) lies practically in the same plane as the thread for cutting.
6. An embroidering machine according to any of claims 1 to 5, characterised in that the nip (29) is practically perpendicular to the surface of the metal part (13) constituting the presser foot (15) and extends practically in the same direction as the movement of the knife (19) when cutting the thread.
7. An embroidering machine according to any of claims 1 to 6, characterised in that the thread gripper (27) has a recess (77) for guiding the knife (19).
8. An embroidering machine according to any of claims 1 to 7, characterised in that the thread gripper (27) has a stationary part (61) and a movable or resilient part (63).
9. An embroidering machine according to claim 8, characterised in that the thread gripper (27) has flat teeth (69) which form the nip (29).
10. An embroidering machine according to claim 9, characterised in that the teeth (69) on the side of the nip (29) engage in a recess (71) in the other part of the thread gripper (27).
11. An embroidering machine according to any of claims 1 to 8, characterised in that the thread gripper (27) is made of plastic.
12. An embroidering machine according to any of claims 1 to 11, characterised in that the stationary part (61) is U-shaped and in that the resilient part (63) is disposed between the arms of the U and an arcuate plastic spring (73) is formed on it.
13. An embroidering machine according to claim 12, characterised in that after the resilient part has been inserted the plastic spring (73) exerts a predetermined force against opening the nip (29).
14. An embroidering machine according to claim 12, characterised in that a stop (75) is provided and limits the distance by which the nip (29) can be opened.
15. A front-thread gripper according to any of claims 5 to 14.

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