CN107923096B

CN107923096B - Method for actuating a thread cutting and clamping device and associated device

Info

Publication number: CN107923096B
Application number: CN201780002881.2A
Authority: CN
Inventors: 法兰兹·拉瑟; 汉诺·努斯堡摩
Original assignee: Laesser AG
Current assignee: Laesser AG
Priority date: 2016-05-03
Filing date: 2017-02-22
Publication date: 2020-09-11
Anticipated expiration: 2037-02-22
Also published as: WO2017190862A1; CH712431A1; CN107923096A; EP3452653A1; KR20190002457A; TWI696736B; EP3452653B1; TW201739981A

Abstract

The method relates to an actuating device (21, 23) of a thread cutting and clamping device (33) at an embroidery point of a large embroidery machine, wherein a device for fixing a shuttle is used for cutting and clamping a shuttle thread (68). The invention further relates to a device for actuating a yarn cutting and clamping device (33), wherein a plurality of yarn cutting and clamping members (75) can be actuated simultaneously by one device (46).

Description

Method for actuating a thread cutting and clamping device and associated device

Technical Field

The subject of the invention is a method for actuating a yarn cutting and clamping device according to the preamble of claim 1 and an actuator of a device for carrying out said method according to claim 4.

Background

During embroidery on an embroidery machine, each yarn must be cut when changing the dye, pattern, or repeating pattern. This work is performed manually during early embroidery on a mechanical embroidery device. However, yarn cutting devices of large embroidery devices have been known for many years, which are assigned to each individual embroidery point and can be controlled by means of a program in order to sever individual or a plurality of selected shuttle threads between the shuttle and the material to be embroidered. Such a yarn cutting device is known, for example, from EP 0638682B 1.

In designing such automatic yarn cutting apparatuses, designers are always faced with the problem of constructing a yarn cutting device that must be installed in an extremely narrow space on a large embroidering device. It is considered that a large embroidery device is equipped with up to one thousand embroidery points, i.e., one thousand needles and a shuttle plate having a shuttle. Furthermore, the end of the yarn from the embroidery base fabric should be positioned as short distance above the embroidery base fabric as possible and the longer cut end from the shuttle or spool in the shuttle must be kept in a position so that after further changing of the dye, embroidery can be easily resumed at the temporarily fixed point of embroidery.

By means of the device described above according to EP 0638682B 1, at least the bobbin thread on the side of the shuttle plate (shuttle guide unit) can be cut off. However, it has turned out that the ends of the yarns coming from the material to be embroidered are relatively long and the second ends coming from the shuttles are not positioned in a precisely defined position. This may cause a problem in restoring embroidery.

Furthermore, a shuttle-type embroidery machine with a drive rod unit which makes it possible to fix each individual shuttle independently is known from EP 1055761B 1. Fixing the shuttle prevents the severed end of the yarn from being damaged, in fact even completely crushed, at the fixed shuttle due to the rapid upward and downward movement of the shuttle, which would otherwise no longer guarantee that the embroidery can be carried out safely. In order to fix each individual shuttle, a pneumatic piston cylinder unit is provided for each shuttle, by means of which a lower drive pin in the drive rod can be extended out of the shuttle race plate area by means of an angle lever. After the drive pins are extended, the shuttles positioned in the respective shuttle plates slide slightly downward and remain in this position. To resume embroidery, the drive pin is guided back to the shuttle plate by the pneumatic cylinder unit, and the shuttle is raised slightly again during the guiding of the drive pin. Because the shuttle is stopped, the undesirable yarn exiting the stopped shuttle is not damaged during embroidery.

Disclosure of Invention

One object of the present invention is now to build a method and apparatus that allows to cut the shuttle-thread between the needle plate and the embroidery base having the embroidery close to the embroidery base. A further object is to temporarily secure the cut end of the yarn between the shuttle and the embroidery base until the stopped embroidery point is back in operation.

These objects are achieved according to the method for actuating a yarn cutting and clamping device according to the features of claim 1 and according to the device according to the features of claim 4.

The present invention makes it possible to cut off an individual shuttle thread at each embroidery point close to an embroidery base economically and safely and firmly clamp the end of the yarn extended to the shuttle in a fastened manner at a needle plate region until such time as to resume embroidery at the corresponding embroidery point. The use of the existing pneumatic piston cylinder unit driver for fixing the shuttle by retracting the driving pin makes it possible to guide the yarn cutting and clamping device safely and precisely in time between the embroidery substrate with embroidery and the needle plate surface, and to perform two kinds of actuation, i.e., cutting and stable clamping, here. The cut-off shuttle thread has only a short section of yarn protruding from the embroidery base and the second end extending to the shuttle is safely retained and can thus not be damaged during further embroidery processes of adjacent embroidery points. The yarn held in the clamping device is ready to be embroidered at any time.

The design of the device makes it possible to produce the device also very economically, since the conversion drive can be used for a plurality of, for example, 48, embroidery points in combination in order to activate the yarn cutting and clamping device. In other words, a single drive makes it possible to actuate the yarn cutting and clamping arrangement at, for example, 48 or more points. In addition to representing a cost saving, having only one drive for 48 or more embroidery points makes it easier to control the drives for cutting and clamping and, in addition, requires much less space, so that the area of the individual embroidery points on the shuttle side is less obstructed.

Drawings

The invention is explained in more detail with reference to exemplary embodiments, in which:

figure 1 shows a vertical section through a needle plate of a large embroidery machine, a drive rod and a device for fixing individual shuttles according to EP 1055761,

fig. 2 shows a cross section according to fig. 1, with the lower drive pin retracted,

fig. 3 shows a cross section according to fig. 1, but with the drive rod in the raised position,

fig. 4 shows the needle plate, the drive rod and the area of the drive for the fixed shuttle, as well as the arrangement according to the invention for cutting the shuttle thread, i.e. the view of the thread cutting and catching device in a separated state,

fig. 5 shows a cross section through the needle plate, the drive rod and the area of the drive holding the shuttle and the arrangement according to the invention for cutting the bobbin thread before the cutting operation with the engaged thread cutter, the thread cutting and catching device being in a state separated from the thread,

fig. 6 shows a cross section through a needle board of a shuttle guide (shuttle guide unit), with the yarn cutter in a yarn capturing position,

figure 7a shows a side view of the yarn cutter arrangement in the open position,

figure 7b shows a view of the yarn cutter arrangement in figure 7a in the open position,

figure 7c shows a side view of the yarn cutter arrangement in the closed position,

figure 7d shows a view of the yarn cutter arrangement of figure 7c in the closed position,

figure 7e shows a side view of the yarn cutter arrangement in an intermediate position,

figure 7f shows a view of the yarn cutter arrangement of figure 7e in an intermediate position,

figure 7g shows a perspective detail of the cutting and clamping part in an intermediate position,

FIG. 8 shows a view of the needle board on the work piece side, an

Fig. 9 shows a schematic cross section of the shuttle guide unit and the yarn cutting and clamping device 33 via the rest position.

Detailed Description

In fig. 1, on the left side, a drive rod 1 is visible, which extends over the entire length of the embroidery machine with a plurality of embroidery points and has an upper drive pin 3 and a lower drive pin 5. The two drive pins 3 and 5 are positioned at a distance from the needle plate 7 with the suture holes 72 and project with their end regions 3 'and 5' into the shuttle race plate 9 of the shuttle guide unit 48. The drive rod 1 is formed such that it can be moved in a swinging manner according to the arrow P in a substantially vertical direction, for example at an inclination of 15 ° relative to the vertical, by means of a known drive member (not shown).

In order to fix or stop the shuttle 11 at the desired point of embroidery of the embroidery machine, the lower drive pin 5 arranged here, shown in the horizontal direction in the drawing, can be displaced according to the arrow Z and pulled away from the shuttle race plate 9 (position according to fig. 2). Thereafter, the shuttle 11 is no longer moved by the drive rod 1, because the lower drive pin 5 is no longer in contact with the shuttle 11 when the drive rod 1 is raised. In fig. 1, the lower drive pin 5 is pushed in and the shuttle 11 is held between the two drive pins 3 and 5 with a gap not visible in fig. 1.

In fig. 2, the lower drive pin 5 is in a retracted position so that the shuttle 11 slides slightly downwards and remains in a lower position in the shuttle race plate 9. The lower drive pin 5 is retracted, for example, by means of an angle lever 13, which angle lever 13 is rotatably supported at its bend 15 about the axis of rotation B. The shorter arm 17 of the angle lever 13 engages with the end of the piston rod 19 of a piston 23, said piston 23 being displaceable in a cylinder 21. The piston 23 can be moved upwards by a fluid, such as compressed air, which is introduced into the lower cylinder space by a valve 25 against the force of a spring 27 (as shown in fig. 1 and 2). During the embroidering operation, the longer arm 29 of the angle bar 13 on the right side of the radially projecting finger 31 fixed to the lower driving pin 5 is positioned slightly at a distance.

By reducing the pressure in the cylinder 21, the piston 23 with the piston rod 19 is guided downwards by the spring 27, as a result of which the angle lever 13 rotates in the counterclockwise direction and pulls the lower drive pin 5 out of the region of the shuttle plate 9 into the position shown in fig. 2. After retraction of the drive pin 5 and raising of the drive rod 1, the angle lever 13 can be rotated back to the starting position. Thus, despite the oscillation of the drive rod 1 in the direction of arrow P, the shuttle 11 can no longer move upwards in the shuttle race plate 9 due to the lack of engagement of the lower drive pin 5. The shuttle 11 stops.

Fig. 3 shows the drive bar 1 in a raised position in which the angle lever 13 is positioned outside the engagement range with the fingers 31 on the lower drive pin 5 during a counterclockwise rotational movement. From this position, the drive pin 5 can also be pushed back into the shuttle 9 after lowering the drive rod 1.

According to the invention, the yarn clamping and cutting device 33 is actuated in the lowest position of the shuttle 11 (see figures 4-6, 9). According to fig. 4 and 5, the yarn clamping and cutting device is driven by a connecting rod 35, the connecting rod 35 being lockable to the long arm 29 of the angle bar 13. The connecting rod 35 is rotatably supported on one side on a shaft 37 of a column 39 of the yarn clamping and cutting device 33. The other free end 36 of the connecting rod 35 rests on the side arm 42 of the lifting device 46. The lifting device 46 extends over a plurality of, for example, 48, embroidery points and makes it possible to release (fig. 4) or engage in the connecting rod 35 at an embroidery point from a male connecting assembly 49 with the long arm 29 of the angle bar 13 (fig. 5). The connecting member 49 includes, for example, a semicircular groove 50 at the lower side of the connecting rod 35 and opened at one side, and a cylindrical cam 52 formed to protrude laterally from the long arm 29 (see also fig. 5). The connecting rod 35 is preferably held pressed against the cam 52 or the side arm 42 of the device 46 by means of a shelf spring 69 until such time as the free end 36 of the connecting rod 35 is raised by the device 46.

If the cam 52 on the angle lever 13 is pushed into the groove 50 of the connecting rod 35, the yarn catching and cutting device 33 can be rotated backward and forward together with the angle lever 13 and the connecting rod 35 about the rotation axis a formed at the lower end thereof. If, as mentioned above, the long arm 29 on the angle lever 13 is not connected to the connecting rod 35, the long arm 29 is used to push the lower driving pin 5 forward or backward. Then, the yarn cutting and clamping device 33 is in a separated state.

The yarn cutting and clamping device 33 is described in more detail with reference to fig. 6 and 7a-7 g. The blade bar 63 projects upwardly on a post 39, which post 39 is connected to a support 73 of the embroidery machine at a rotational axis a. The upper end of the blade bar 63 extends to the area between the two drive pins 3 and 5 (not shown in cross-section according to fig. 6). The upper end of the blade bar 63 engages from below into the slots 51 of the first clamping assembly 45 and the second blade 43 of the severing and clamping arrangement 75 of the bobbin thread 68 (see fig. 7). The cutting and clamping arrangement 75 comprises a first blade 41 made of a rectangular flat body made of metal, the rear end 70 of which is formed in a T-shape and the front end of which has a cutting edge 53. The second blade 43 is disposed in contact with the first blade 41, the front end of which is formed in a hook shape and includes a cut-off edge 53' at the rear side of the hook portion. The second blade 43 projects beyond the rear end 70 of the first blade 41 and terminates in a recess 51. The second blade 43 is connected by a second clamping member 45, the front end of which is also formed in a hook shape and the rear end of which, like the second blade 43, comprises a slot 51 at its lower side. Linking the second clamping member 45 at the rear and positioned in parallel is a first clamping member 47 which has a distal edge extending at right angles to the longitudinal edge on the front side (on the right in fig. 7) and is formed substantially in a T-shape at its rear end 70.

The two

blades

41, 43 and the two

clamping assemblies

45, 47 are positioned in lateral contact with each other and are retained in an oblong channel 59 in the shuttle guide unit 48 (see fig. 6). The two T-shaped end regions of the second blade 43 and of the second clamping assembly 45 are positioned in lateral contact with the shuttle guide unit 48 and are pressed against the shuttle guide unit 48 by means of the clamping holder 67. The first blade 41 and the rear or rear end 70 of the first clamping assembly 47 project beyond the shuttle guide unit to the left in fig. 6 and engage the free end of the blade bar 63. The front hook-shaped end of the second blade 43 and the second clamping assembly 45 projects beyond the shuttle guide unit 48 and the needle board 7, which is not shown in fig. 6.

The mode of operation of the yarn cutting and clamping device 33 with the cutting and clamping arrangement 75 as described above is explained in more detail below. As shown in fig. 2, after the shuttle 11 of a specific embroidery point is fixed by retracting the driving pin 5 from the shuttle walking plate 9, the connecting rod 35 is rotated in the counterclockwise direction by the rack spring 69 by the side arm 42 of the lowering device 46, and the groove 50 of the lower side of the connecting rod 35 is latched into the latch 52 on the long rod 29. The shelf spring 69 also secures the latch during subsequent severing and clamping operations. The angular lever 13 is then rotated in the clockwise direction by means of the piston and

cylinder arrangement

21, 23, by means of which piston and

cylinder arrangement

21, 23 the shuttle 11 was previously stopped at the embroidery point described herein by retracting the lower driving pin 5, as a result of which the strut 39 is also rotated in the clockwise direction about the rotation axis a by means of the connecting rod 35. The rotation of the support post 39 also causes the blade bar 63 fixed thereto to rotate and push the second blade 43 and the second clamping assembly 45 to the right (see fig. 6). Then, the hook-shaped ends of the second blade 43 and the second clamping member 45 protrude beyond the needle plate 7 behind the embroidery base 79, and thus the embroidery base 79 is slightly raised to the right side by the needle plate 7 or preferably held at a distance from the needle plate 7 in advance by the spreader 77 (fig. 6) of the embroidery base 79. In order to catch the bobbin thread 68 of the shuttle 11 guided from the embroidery substrate 79 (on the right side of the catching hook 54) into the shuttle plate 9, the frame on which the embroidery substrate 79 is stretched is displaced so that the bobbin thread 68 is caught by the hook 54, which hook 54 is formed by the second blade 43 and the hook-shaped end of the second clamping member 45 (see fig. 8). Then, the blade lever 63 is rotated by rotating the angle lever 13 in the counterclockwise direction and pulls the second blade 43 and the second clamping assembly 45 to the left together with the upper end thereof and also pulls the shuttle 68 together therewith in the direction of the needle board 7. The bobbin thread 68 guided from the embroidery base 79 to the shuttle 11 is first firmly clamped between the second clamping assembly 45 and the first clamping assembly 47. Then, the shuttle 68 is thereby cut at the cutting edge 53' of the second blade 43 and the cutting edge 53 of the first blade 41. The end of the bobbin thread 68 continued to be stretched to the embroidery substrate 79 now freely protrudes from the embroidery substrate 79 in a little tail form. The shuttle thread 68 is not released again from the clamped state until the embroidery point is back in operation and the shuttle 11 is thereby also driven again by the drive rod 1.

The yarn cutting and clamping device 33 is then positioned as shown in figure 9. The leaf springs 65 on the blade bars 63 ensure that the yarn cutting and clamping arrangement 75 no longer projects beyond the surface of the needle board 7 (fig. 9).

Claims

1. A method for actuating a yarn cutting and clamping device (33) at any embroidery point of a large embroidery machine to cut a bobbin thread (68) and fix and clamp the end of the cut bobbin thread (68),

the method is characterized by comprising the following steps:

coupling the yarn cutting and clamping device (33) to an actuating device (21, 23) having a lifting device (46),

a yarn cutting and clamping arrangement (75) is moved to the outside of the rear side of a needle plate (7),

capturing the bobbin thread (68) exiting from a shuttle (11),

moving the yarn cutting and clamping arrangement (75) back in the direction of the needle plate (7),

clamping the bobbin thread (68), an

The shuttle line (68) is severed between a clamping point of the yarn cutting and clamping arrangement (75) and a stretch embroidery base (79).

2. Method according to claim 1, wherein the yarn cutting and clamping arrangement (75) is moved back through the needle plate (7) into a channel (59) by means of the actuating devices (21, 23) to catch and cut and clamp the bobbin thread (68).

3. Method according to claim 1 or 2, wherein the yarn cutting and clamping arrangement (75) is temporarily connected to the actuating means (21, 23) with the interposition of a connecting rod (35) to secure a lower driving pin (5) by means of the lifting means (46) extending over a plurality of embroidery points.

4. An actuator for actuating a thread cutting and clamping device (33) on a large embroidery machine with a plurality of embroidery points, said actuator comprising a lower drive pin (5) and an upper drive pin (3) for driving shuttles (11) in an oscillating manner in a shuttle walk plate (9) of a shuttle guide unit (48) on the rear side of a needle plate (7), said actuator further comprising suitable actuating means (21, 23) for fixing the individual shuttles (11),

the method is characterized in that:

in order to stop a shuttle (11), the actuating device (21, 23) is formed so that it can be coupled to the yarn cutting and clamping device (33) by means of a connecting rod (35).

5. Actuator according to claim 4, wherein for stopping a shuttle (11) the actuating means (21, 23) comprise a linear drive by means of which an angle lever (13) can be rotated back and forth and by means of which the lower drive pin (5) can be guided into and out of the shuttle (9).

6. Actuator according to claim 5, wherein the angle lever (13) is hinged by its first short arm (17) to a piston rod (19) of the linear drive and a long arm (29) of the angle lever (13) is engageable with the lower drive pin (5) when a drive rod (1) is lowered.

7. Actuator according to claim 6, wherein said connecting rod (35) is connectable to said long arm (29) of said angular lever (13) and said yarn cutting and clamping device (33) is actuatable by rotating said angular lever (13) together with a support (39).

8. Actuator according to claim 7, wherein a blade bar (63) is formed on said post (39), at the free end of which a yarn cutting and clamping arrangement (75) is fixed.

9. Actuator according to claim 7 or 8, wherein said connecting rod (35) is connectable to said angular lever (13) by rotating about a rotation axis (37) formed on said yarn cutting and clamping device (33).

10. Actuator according to claim 9, wherein said connecting rod (35) is rotated by means of a lifting device (46), said lifting device (46) acting on the free end of said connecting rod (35) and extending over a plurality of embroidery points arranged adjacent to each other.

11. The actuator according to claim 7, wherein said connecting rod (35) is connected to said angle rod (13) by lowering said connecting rod (35) to a cam (52) on said angle rod (13).

12. Actuator according to claim 7, wherein the yarn cutting and clamping device (33) comprises on its lower end the pillar (39) hinged on the big embroidery machine, an upwardly projecting blade bar (63) arranged on the pillar (39) and its upper end engaged with a yarn cutting and clamping arrangement (75), the yarn cutting and clamping arrangement (75) being axially displaceable on a channel (59) in the shuttle guide unit (48) and in the needle plate (7).

13. Actuator according to claim 12, wherein the yarn cutting and clamping arrangement (75) comprises blades (41, 43) and clamping members (45, 47) displaceable relative to each other, wherein one blade and one clamping member each have a hook-shaped end (64).