Thread guide element and yarn clearer for a workstation of a textile machine with a thread guide element

Abstract

The present invention relates to a thread guide element for a yarn monitoring and/or yarn processing unit as well as to a yarn clearer for a workstation of a textile machine with at least one thread guide element.

Claims

1. A thread guide element (1) for a yarn monitoring and/or yarn processing unit, comprising: a thread guide opening (2) configured to guide a thread laterally to a thread path, a thread pick-up opening (19) configured to enable the thread to be inserted into the thread guide opening (2), an air flow equalisation opening (3) configured to: equalize static pressure on both sides of the thread guide element (1); and/or generate a laminar air flow on one side of the thread guide element (1) at least in the area of the guided thread; wherein the air flow equalisation opening (3) is round or elliptical in its opening plane and in its outlet plane.

2. The thread guide element (1) according to claim 1, wherein the thread guide opening (2) is formed in a forked shape with two thread guide sections (4) between which the thread is guided and/or between which the two thread guide sections (4) converge in a U- or V-shaped thread guide area (5).

3. The thread guide element (1) according to claim 1, wherein the air flow equalisation opening (3): is configured to completely penetrate the thread guide element (1) in a thread running direction; and/or is arranged such that it is spaced apart from and/or adjacent to the thread guide opening (2).

4. The thread guide element (1) according to claim 1, wherein the air flow equalisation opening (3) is arranged on a side of the thread guide opening (2) facing away from the thread pick-up opening (19), centrally with respect to the thread guide opening (2).

5. The thread guide element (1) according to claim 1, wherein a length of the thread guide opening (2) along the thread path: is between 1 mm and 3 mm; and/or is longer than a width of the thread guide opening (2) by at least a factor of 2.0.

6. The thread guide element (1) according to claim 1, further comprising: a thread guide section (7) extending along a thread running direction; and a flow-calming section (6), in which no thread guidance takes place, extending along the thread running direction and adjacent to the thread guide section (7).

7. The thread guide element (1) according to claim 6, wherein the air flow equalisation opening (3): is formed on a side of the thread guide section (7) facing away from the thread pick-up opening (19), and comprises, at least in an extension region of the thread guide section (7) along the thread running direction, a flow-calming surface (8) optimised by computational fluid mechanics calculations, configured to generate a laminar air flow in the flow-calming section (6) and/or in a region adjacent thereto.

8. The thread guide element (1) according to claim 6, wherein the air flow equalisation opening (3) comprises a flow-calming surface (8) extending over the thread guide section (7) and positioned at an angle between 40 and 50 with respect to the thread running direction.

9. The thread guide element (1) according to claim 1, wherein the air flow equalisation opening (3) has an air flow outlet plane, the normal vector of which points in a direction away from the thread pick-up opening (19) confining an angle with the thread path.

10. The thread guide element (1) according to claim 1, further comprises a positioning aid (17), configured to position the thread guide element (1) on a yarn monitoring or yarn processing unit, wherein the positioning aid (17) is provided on a side of the thread guide element (1) facing away from the thread pick-up opening (19) and/or the air flow equalisation opening (3).

11. A yarn clearer (9) for a workstation of a textile machine, comprising: a thread guide channel comprising: a thread inlet configured to enable the thread to be fed; and a thread outlet configured to discharge the thread; and at least one thread guide element (1) according to claim 1.

12. The yarn clearer (9) for a workstation of a textile machine according to claim 11, further comprising a thread guide element (1) arranged at an inlet and/or at an outlet of the thread guide channel.

13. The yarn clearer (9) for a workstation according to claim 11, wherein: the thread guide channel is configured to delimit at least one sensor range (10) of a sensor, surrounded by the yarn clearer (9), configured to detect defined parameters of the thread running through the thread guide channel, and a normal vector of an air flow outlet plane of the air flow equalisation opening (3) points in a direction of an edge area of the sensor range (10) opposite the thread pick-up opening (19).

Description

(1) FIG. 1: shows a schematic front view of a thread guide element with the inlet side for a thread;

(2) FIG. 2: shows a schematic sectional view of two of a thread guide element shown in FIG. 1, and

(3) FIG. 3 shows a perspective schematic view of a yarn clearer.

(4) A thread guide element 1 for a yarn clearer 9 of a workstation of a textile machine, shown schematically in FIG. 1, is formed in one piece and has two thread guide sections 4 arranged in a forked shape with one another, which converge in a V-shape in a thread guide area 5 from the direction of a thread pick-up opening 19. In this case, the two thread guide sections 4 form a gap that is used as a thread guide opening 2 that is open on one side. In the thread guide area 5 of the thread guide opening 2, a thread can be guided at high speed and protected against lateral deviations of the thread path.

(5) The thread guide opening 2 has smooth surfaces aligned in the thread running direction so that the thread can be guided at high speed with as little adhesion as possible. However, the fibres protruding from the surface of the thread moving rapidly in the direction of the thread path create suction, which results in an air flow in and behind the thread guide element 1 and a pressure differential in front of and behind the thread guide element 1.

(6) To equalise this static pressure differential, the thread guide element 1 has an air flow equalisation opening 3 with an elliptical opening below the thread guide opening 2, in which case the air flow equalisation opening 3 completely penetrates the thread guide element 1 in the direction of the thread path.

(7) In this context, FIG. 2 shows two thread guide elements 1 in a schematic sectional view, one thread guide element 1 being arranged on the inlet side and the other thread guide element 1 being arranged on the outlet side of a sensor range of a yarn clearer 9, which is not shown running between the two thread guide elements 1.

(8) In order to avoid a turbulent air flow on the thread outlet side of the thread guide element 1 and to generate a laminar air flow instead, the respective thread guide element 1 has a flow-calming section 6 adjacent to a thread guide section 7 along the thread path and directly adjoining it. In this case, the thread guide element 1 is integrally formed with the thread guide section 7 and the flow-calming section 6.

(9) In this case, the flow-calming section 6 has at least one flow-calming surface 8 that has been optimised by computational fluid dynamics calculations to produce a particularly laminar air flow in and behind the thread guide element 1. In this case, the thread guide element 1 has a flow-calming surface 8 in the thread guide section 7, which runs towards the thread or the thread path at an angle of about 45 and leads to a deflection of the resulting air flow.

(10) FIG. 3 shows a schematic perspective view of an embodiment of a yarn clearer 9 with a thread guide element 1 as described above. The thread guide element 1 is arranged along a thread path on the inlet side to a sensor range 10 of the yarn clearer 9. Alternatively or additionally, according to a further embodiment, such a thread guide element 1 may be arranged along the thread path on the outlet side of the sensor range 10.

(11) The yarn clearer 9 according to the illustrated embodiment has a housing body 11 formed in three parts with a first and a second housing part 12, 13 each for accommodating a sensor system monitoring the thread crossing the sensor range 10 bounded on the inlet side by the thread guide element 1. For example, one of the first and second housing parts 12, 13 can include a capacitive sensor system and the other housing part can include an optical sensor system for monitoring different thread parameters. The third housing part 14 of the housing body 11 is arranged along the thread path adjacent to the second housing part 13, the third housing part 14 partially enclosing a cutting device with a cutting knife 15 crossing the thread path of the yarn clearer 9 and having a stop 16 for the cutting knife 15 for severing a thread (not shown) running in between.

LIST OF REFERENCE NUMBERS

(12) 1 Thread guide element 2 Thread guide opening 3 Air flow equalisation opening 4 Thread guide section 5 V-shaped thread guide area 6 Flow-calming section 7 Thread guide section 8 Flow-calming surface 9 Yarn clearer 10 Sensor range 11 Housing body 12 First housing part 13 Second housing part 14 Third housing part 15 Cutting knife 16 Stop 17 Recess/positioning aid 18 Flange 19 Thread pick-up opening