Yarn cleaner and cutting device for a yarn cleaner

Description

[0001] The invention relates to a cutting device for a yarn cleaner that can be arranged at a workstation of a textile machine, with a cutting knife with a cutting edge adjustable between a rest position and a cutting position and an anvil arranged on an anvil carrier in an operating position, in which a stop surface of the anvil interacts with the cutting edge of the cutting knife in the cutting position.

[0002] In yarn production, the aim is typically to achieve the highest possible yarn uniformity within tight tolerances and to produce yarn free of defects, particularly visible ones such as unacceptable thick or thin spots. To achieve this, so-called yarn cleaners are used at individual workstations of a textile machine. These cleaners continuously monitor the yarn diameter using a suitable measuring head. If an unacceptable defect is detected due to exceeding or falling below the limit values ​​known as cleaning limits, the defect is cut out of the yarn using the yarn cleaner's cutting device, the yarn ends are rejoined, and the production process continues.

[0003] Known cutting devices for yarn cleaners are, for example, electromagnetically actuated, being designed either in the manner of scissors or in the manner mentioned above in the manner of a chisel, with this design being preferred due to its simpler construction.

[0004] However, a disadvantage of this design is that the service life of the cutting blades that work in conjunction with anvils is shorter compared to scissor-like cutting devices. This is because the way these cutting devices work, where the blade of the cutting knife strikes the anvil's stop surface with a predetermined impact force to cut the yarn, leads to increased wear, which necessitates regular replacement of the cutting knife or the anvil to maintain consistent cutting performance.

[0005] DE 17 85 157 B1 discloses a cutting device according to the preamble of claim 1.

[0006] Based on this, the invention aims to provide a yarn cleaner with a cutting device as well as a cutting device with a cutting knife and an anvil, which is characterized by long service life.

[0007] The invention solves the problem by means of a cutting device with the features of claim 1 and by means of a yarn cleaner with the features of claim 11. Advantageous further developments of the cutting device are specified in the dependent claims.

[0008] In the cutting device according to the invention, it is provided that the anvil has at least two stop surfaces that can be arranged on the anvil carrier in the operating position and is adjustable on the anvil carrier to select the stop surface that can be brought into operative contact with the cutting edge.

[0009] According to the invention, the anvil has at least two separate stop surfaces, allowing it to be positioned on the anvil support in two positions during operation. In each of these positions, one of the at least two stop surfaces interacts with the cutting edge of the cutting knife. Without replacing the anvil, it is therefore possible, for example, in the event of excessive wear of the first stop surface, to adjust the anvil relative to the anvil support so that, in the operating position, the second stop surface then acts as a counter-bearing against the cutting edge of the cutting knife, between which a yarn can be cut if necessary.

[0010] To select the stop surface that can be brought into operative contact with the cutting edge, the invention provides that the anvil is adjustable on the anvil support. This adjustability allows, if necessary, the anvil's stop surface opposite the cutting edge to be conveniently selected from its at least two stop surfaces. The configuration of the connection between the anvil and the anvil support, such that the support can be selectively positioned with at least one of the at least two stop surfaces in the operating position, is generally freely selectable. According to a particularly advantageous embodiment of the invention, the anvil is detachably mounted on the anvil support. "Detachable" means that the anvil can be removed from the support without damage, and in particular, repeatedly.This embodiment of the invention makes it possible to align the anvil in a particularly simple and convenient manner so that, in the operating position, the desired stop surface interacts with the cutting edge of the cutting knife. For example, if necessary, due to wear of the first stop surface, the anvil can be detached from the anvil carrier by means of the detachable connection and then aligned and reattached to the anvil carrier by the operator so that, in the operating position, the at least second stop surface interacts with the cutting edge of the cutting knife in the cutting position.

[0011] Reliable operation and long service life of the cutting device can be achieved by aligning the cutting edge of the cutting knife parallel to the stop surface of the anvil in the cutting position. This ensures both an even load distribution on the stop surface and the cutting edge, as well as a clean cut of the yarn to be separated by the cutting device. According to the invention, the anvil is pivotally connected to the anvil support in the operating position such that the cutting edge, in the cutting position, aligns the stop surface and the cutting edge in a fixed, parallel position.

[0012] According to the invention, the anvil, which is connected to the anvil carrier in the operating position, can be adjusted in its orientation relative to the cutting blade due to its articulated arrangement on the anvil carrier. Thus, after initial mounting of the anvil on the anvil carrier in the operating position, it is possible to adjust the contact surface between the cutting edge and the anvil carrier by first moving the cutting edge from its rest position to the cutting position, so that the contact surface is aligned, in particular, parallel to the cutting edge.The articulated adjustment of the anvil relative to the anvil support makes it possible to align the cutting edge and the stop surface in the cutting position parallel and preferably over a complete cooperating extension length over which the cutting edge comes into contact with the stop surface in the cutting position, without the need for any further aids.

[0013] After the initial alignment of the stop surface by the cutting edge of the cutting knife, the anvil then remains in the position set by the cutting knife due to the intended articulated design, so that the stop surface is fixedly aligned with respect to the cutting edge.

[0014] This embodiment of the invention ensures, in a particularly reliable manner, optimal alignment of the stop surface with respect to the cutting edge. Angular deviations of the cutting edge with respect to the stop surface between the rest position and the cutting positions can thus be automatically compensated for by a single initial movement of the cutting edge into the cutting position, in which the stop surface is optimally aligned with the cutting edge.

[0015] The design of the articulated connection between the anvil support and the anvil is generally freely selectable, with particular preference being provided that the anvil is pivotally connected to the anvil support to ensure, in particular, the parallel alignment of the stop surface with respect to the cutting edge in the cutting position. A pivotally connected connection, in which the at least two stop surfaces are preferably arranged on a circumferential surface of the anvil extending at a distance from the pivot axis of the anvil and the anvil support, allows the stop surface to be aligned, in particular, parallel to the cutting edge in a particularly simple manner by means of a rotation about the pivot axis.A corresponding further development of the invention also allows for a simple change of the stop surface, whereby the anvil only needs to be rotated around the pivot axis until an alternative stop surface is arranged in the operating position opposite the cutting edge.

[0016] The anvil can be fixed to the anvil support in its operating position by any means, for example, by positive-locking connecting elements. However, according to a particularly advantageous embodiment of the invention, the anvil is force-fitted to the anvil support in its operating position, in particular by being screwed to the anvil support with a defined preload.

[0017] This embodiment of the invention allows for a particularly simple and convenient adjustment of the anvil's stop surface relative to the cutting edge of the cutting blade. To adjust the anvil relative to the anvil support, it is only necessary to loosen the existing frictional connection, in particular the screw or locking mechanism, so that the anvil can then be adjusted accordingly, in particular rotated about the longitudinal axis of the screw or locking mechanism. Furthermore, the design of the frictional connection, in particular the screw or locking mechanism with a defined preload force, allows the cutting device to be designed in a particularly simple and convenient manner in the further developed way, whereby the cutting edge, in the cutting position, aligns the stop surface with the cutting edge in a fixed position, in particular parallel to the cutting edge.The force-fit connection, in particular the defined preload force, is designed in such a way that a hinged adjustment can be effected via the force acting on the anvil via the cutting blade, and the set position is subsequently maintained via the force-fit connection, in particular the preload force, so that the anvil is fixed in position relative to the cutting blade during further operation of the cutting device.

[0018] Particularly advantageously, it is provided that the anvil in the operating position is adjustable and pivotally connected to the anvil carrier against a spring force, in particular by means of a swivel joint, and is screwed to the anvil carrier using a spring element acting in the direction of the preload force.

[0019] The advantageously provided fixing of the anvil to the anvil carrier in the operating position using a spring force, in particular a screwing or locking of the anvil to the anvil carrier using a spring element acting in the direction of the preload force of the screwing or locking, allows in a particularly simple and reliable way to ensure a hinged adjustment possibility of the anvil on the anvil carrier in conjunction with the cutting edge, whereby after the adjustment movement a particularly reliable fixed arrangement of the anvil on the anvil carrier in the position set by the cutting knife is ensured.

[0020] According to a further development of the invention, the distance of the cutting edge from the stop surface in the rest position can be adjusted as required, depending on the yarn thickness. Preferably, the relative position or distance between the cutting edge and the anvil can be adjusted as required, depending on the yarn thickness to be cut, by axially changing the position of the anvil and / or the cutting edge. This reliably ensures that a sufficient impulse is generated to cut the yarn.

[0021] The number of stop surfaces on the anvil is generally freely selectable. However, according to a particularly advantageous embodiment of the invention, the anvil has four stop surfaces, which are preferably arranged evenly distributed around the circumference of the anvil. Optionally, more than four stop surfaces can also be provided. The number can be selected such that reliable separation of the yarn by the relative movement of the cutting blade to the stop surface is ensured.

[0022] According to this embodiment of the invention, the anvil is designed as a flat, polygonal, in particular rectangular, and especially preferably square element, which has four stop surfaces on its circumference, each adjoining one another at an angle of substantially 90°. Alternatively, the anvil can also be designed as a pentagonal, hexagonal, etc. element. In the case of an advantageously pivotable connection of the anvil to the anvil support, wherein the axis of rotation preferably extends at a uniform distance from the stop surfaces through the center of the anvil, the stop surface interacting with the cutting edge can be selected by simply rotating the anvil by the corresponding angle, for example, by 90° for a square element and by 60° for a hexagonal element.Overall, this embodiment of the invention allows for multiple changes of the stop surface that engages with the cutting edge. For example, a square element could be changed three times, and a hexagonal element five times, thereby achieving longer service lives.

[0023] According to a preferred embodiment of the invention, at least the contact surfaces of the anvil, or the anvil forming the contact surfaces, have a hardness 5% to 15% lower than that of the cutting edge. This embodiment of the invention ensures a particularly long service life of the cutting blade, whereby the resulting wear of the contact surface of the anvil is compensated for by the fact that the anvil has at least two, preferably at least four, contact surfaces, which are preferably arranged sequentially, for example after reaching a certain wear limit, in the operating position opposite the cutting edge. Furthermore, according to a preferred embodiment, the cutting edge of the cutting blade can be replaceably mounted on the cutting blade, or the cutting blade with the cutting edge can be replaceably mounted on a cutting blade holder.

[0024] According to a particularly preferred embodiment of the invention, the anvil is formed from a sintered material, which allows for a particularly simple and cost-effective production of the striking surfaces or the anvil itself with a desired degree of hardness. For example, the striking surfaces or the anvil forming the striking surfaces can be made from a material such as the commercially known material FD-0205-HT.

[0025] According to a further preferred embodiment of the invention, at least the cutting edge or the cutting blade forming the cutting edge is made of a wear-resistant material with high hardness, wherein the material has a content of at least 4% chromium and at least 4% vanadium. Such materials are known, for example, under the trade names ASP2009, ASP2011, ASP2030, Böhler S390, CMP V9, CMP V10, etc. The wear resistance of the cutting blade and consequently its service life can thus be improved.

[0026] According to a preferred embodiment of the invention, at least the cutting edge, or alternatively the cutting blade which supports the cutting edge in a fixed position relative to the cutting knife, is freely rotatable about an axis of rotation perpendicular to the central axis of the cutting edge or the cutting knife by a defined angular amount relative to an adjustment axis of the cutting edge between the rest position and the cutting position. Preferably, the defined angle is between 0° and 15° inclusive, more preferably between 0° and 10° inclusive, and particularly preferably between 0° and 5° inclusive. The rotatable mounting can be implemented by conventional bearing types that effect rotation. The mounting is particularly preferably designed to allow rotational movement in a plane of rotation by the defined angular amount on both sides of the adjustment axis of the cutting device.As a cost-effective mounting option, a type of hinge device is provided, for example. The hinge device can preferably be designed by an engagement element and an engagement receptacle. For example, the engagement element can be conical or frustoconical in shape, wherein the engagement receptacle has a first receiving section for receiving a section of the lateral surface of the conical or frustoconical engagement element and a second receiving section adjoining the first receiving section for receiving the free end section of the engagement element.The limitation of free rotation can preferably be achieved by the gap dimension, defining the angle magnitude, between corresponding stop surfaces of the first receiving section and the cylindrical surface section to be arranged therein, and / or of the second receiving section and the free end section of the engagement element to be arranged therein. Alternatively or additionally, the cutting blade or cutting edge can have an outer stop surface which, upon reaching the defined angle magnitude, abuts a counter-stop surface to limit the rotation.

[0027] The rotatable mounting of at least the cutting edge or the cutting knife with the cutting edge allows the cutting edge to be aligned with the anvil, thus preventing the formation of burrs that impair cutting performance.

[0028] According to a further aspect of the present invention, a yarn cleaner is proposed. A characteristic feature of the yarn cleaner according to the invention, which can be arranged at a workstation of a textile machine, is that it has a cutting device as described above, or further developed in the invention. The yarn cleaner according to the invention is characterized by its high cutting quality and long service life, during which no change of the anvil is required.

[0029] An embodiment of the invention is explained with reference to the drawing. The drawing shows: Figure 1 shows an exploded view of a perspective view of an embodiment of a cutting device.

[0030] Figure 1 Figure 1 shows a perspective view of an embodiment of a cutting device 1 with an anvil 2 removed from an anvil carrier 7.

[0031] The cutting device 1 has a cutting blade drive 6 by means of which a cutting blade 4, which is interchangeably arranged on a cutting blade carrier 5, can be moved from a rest position, in which a cutting edge 20 is arranged at a distance from a stop surface 3 of the anvil 2, into a cutting position (not shown here), in which the cutting edge 20 rests against the stop surface 3 of the anvil 2.

[0032] In the illustrated embodiment, the anvil 2 has a total of four stop surfaces 3 evenly distributed around its circumference, which make it possible to fix the anvil 2 to the anvil support 7 in a total of four positions in an operating position. For this purpose, the anvil support 7 has a mounting section 18, on the upper surface 19 of which the anvil 2 rests with its lower surface 17 in the operating position. To fix the anvil 2 to the mounting section 18, the mounting section 18 has a threaded bore 8, which serves to receive a fastening screw 9. In the operating position, this screw extends through a central through-hole 12 in the anvil 2 and is screwed into the threaded bore 8 with a threaded section 14.

[0033] In the operating positions of the anvil 2 set by the fastening screw 9 on the anvil carrier 7, a spring element 10, arranged coaxially to the fastening screw 9 and formed by a spring ring, rests against a shoulder 15 of the anvil 2 and against a shoulder 11 adjacent to a coupling section 16 of the fastening screw 9. The spring element 10 allows the preload force, generated via the fastening screw 8 and securing the anvil 2 to the anvil carrier 7, to be adjusted, particularly advantageously, such that when the cutting blade 4 is first moved into the cutting position, the interaction of the cutting edge 20 with the anvil 2 causes the anvil 2 to be moved about the longitudinal axis of the fastening screw 9 so that the cutting edge 20 is aligned parallel to the stop surface 3. The preload force is sufficient to subsequently fix the anvil 2 in the set position.

[0034] The cutting blade carrier 5 is mounted on the cutting blade drive 6 by a hinge device 21 so as to be rotatable about the longitudinal axis of the fastening screw 9. The hinge device 21 consists of a receptacle 22 on the cutting blade carrier 5 and an engagement element (not shown) which is arranged on the cutting blade drive 6 and engages in the receptacle 22. The hinge device 21 allows a rotational movement of the cutting blade carrier 5, and thus of the cutting blade 4 or the cutting edge 20, by a defined angular amount in a plane of rotation on both sides of the adjustment axis of the cutting device 1. Reference symbol list

[0035] 1 Cutting device 2 Anvil 3 Stop surface 4 Cutting blade 5 Cutting blade holder 6 Cutting blade drive 7 Anvil support 8 Threaded hole 9 Mounting screw 10 Spring element 11 Shoulder 12 Through hole 14 Threaded section 15 Shoulder 16 Coupling section 17 Bottom 18 Mounting section 19 Top 20 Cutting edge 21 Hinge device 22 Mount

Claims

1. A cutting device (1) for a yarn clearer which is configured to be arranged at a workstation of a textile machine, having - a cutting knife (4) with a cutting edge (20) that adjustable between a rest position and a cutting position, and - an anvil (2) arranged on an anvil carrier (7) in an operating position in which a stop surface (3) of the anvil (2) interacts with the cutting edge (20) of the cutting knife (4) in the cutting position, - wherein the anvil (2) has at least two stop surfaces (3) which are configured to be arranged on the anvil carrier (7) in the operating position and is adjustably arranged on the anvil carrier (7) for the selection of the stop surface (3) which is configured to be brought into an active connection with the cutting edge (20), characterized in that the anvil (2) is articulated on the anvil carrier (7) in the operating position in such a way that, in the cutting position, the cutting edge (20) aligns the stop surface (3) opposite the cutting edge (20) in a fixed position parallel to each other.

2. The cutting device (1) according to claim 1, characterised in that the anvil (2) is arranged on the anvil carrier (7) in a detachable manner.

3. The cutting device (1) according to one or more of the preceding claims, characterised in that the anvil (2) is connected to the anvil carrier (7) by a rotary joint for parallel alignment of the stop surface (3) with respect to the cutting edge (20) in the cutting position.

4. The cutting device (1) according to one or more of the preceding claims, characterised in that the anvil (2) is frictionally connected to the anvil carrier (7) in the operating position, in particular screwed to the anvil carrier (7) with a defined pretensioning force.

5. The cutting device (1) according to one or more of the preceding claims, characterised in that the anvil (2) in the operating position is connected to the anvil carrier (7) in an articulated manner, in particular by means of a rotary joint, so as to be adjustable against a spring force, in particular it is screwed onto the anvil carrier (7) using a spring element (10) acting in the direction of the pretensioning force.

6. The cutting device (1) according to one or more of the preceding claims, characterised in that the cutting knife (4) or the cutting edge (20) is mounted so as to be freely rotatable about a rotary axis extending perpendicular to the centre axis of the cutting edge (20) by a defined angular amount relative to an adjustment movement axis of the adjustment movement of the cutting edge (20) between the rest position and the cutting position.

7. The cutting device (1) according to one or more of the preceding claims, characterised in that the anvil (2) has four stop surfaces (3) evenly distributed over the circumference.

8. The cutting device (1) according to one or more of the preceding claims, characterised in that the stop surfaces of the anvil (2) have a surface hardness that is 5% to 15% lower than that of the cutting edge (20).

9. The cutting device (1) according to one or more of the preceding claims, characterised in that the cutting edge (20) is formed from a wear-resistant material with high hardness, the material having a content of 4% chromium and of at least 4% vanadium.

10. The cutting device (1) according to one or more of the preceding claims, characterised in that the anvil (2) is made of a sintered material.

11. A yarn clearer for a workstation of a textile machine with a cutting device (1) for clearing out defects from a yarn, characterised in that the cutting device (1) is configured according to one or more of claims 1 to 10.