Air jet spinning machine and method for operating the same

Patent metadata

Field	Value
Publication number	US-9670601-B2
Application number	US-201514737737-A
Country	US
Kind code	B2
Filing date	Jun 12, 2015
Priority date	Jun 12, 2014
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A method for operating an air jet spinning machine having at least one spinning unit with one spinning nozzle for producing a yarn is provided. During the operation of the spinning unit, the spinning nozzle feeds a fiber composite through an inlet in a predefined transport direction. The fiber composite within a vortex chamber of the spinning nozzle receives a twist with the assistance of a vortex air flow, such that a yarn is formed from the fiber composite. With the assistance of at least one sensor system, the yarn leaving the outlet is monitored with regard to defined yarn flaws. The production of yarn is interrupted upon the detection of a corresponding yarn flaw. Between the detection of the specified yarn flaw and the interruption of the yarn production, a cleaning process is carried out during which an additive is fed to the spinning unit and is applied to the fiber composite and/or the yarn produced from the fiber composite and/or on parts of the spinning nozzle.

First claim

The invention claimed is:

1. A method for operating an air jet spinning machine having a spinning unit with a spinning nozzle for producing a yarn, the method comprising:
during operation of the spinning unit, feeding a fiber composite to the spinning nozzle through an inlet and in a predefined transport direction, wherein the fiber composite within a vortex chamber of the spinning nozzle receives a twist with the assistance of a vortex air flow, such that a yarn is formed from the fiber composite and leaves the spinning nozzle through an outlet;
monitoring the yarn leaving the outlet with at least one sensor system with regard to defined yarn flaws;
interrupting production of the yarn upon the detection of a corresponding yarn flaw;
between detection of the specified yarn flaw and interruption of the yarn production, performing a cleaning process for a specified period of time during which an additive is fed to a location either within the spinning nozzle or upstream of the spinning nozzle and is applied to one or more of: (1) the fiber composite; (2) the yarn produced from the fiber composite; or (3) parts of the spinning nozzle.

2. The method according to claim 1 , wherein the sensor system is deactivated during the cleaning process and evaluation of measured values delivered by the sensor system is interrupted during the specified period of time.

3. The method according to claim 1 , wherein on the basis of measured values delivered by the sensor system during the cleaning process, one or both of a qualitative or quantitative monitoring of the additive feed takes place.

4. The method according to claim 1 , wherein after the interruption of yarn production, with the assistance of a yarn removal unit, a yarn section containing the yarn flaw and a yarn section produced during the cleaning operation are removed from the yarn, and further comprising performing a subsequent piecing process wherein an end section of the remaining yarn is guided through the spinning nozzle against the transport direction, is brought into contact with the fiber composite and is subsequently introduced into the spinning nozzle in the transport direction together with the fiber composite.

5. The method according to claim 1 , wherein a yarn delivery speed of the spinning nozzle during the cleaning process is less than the yarn delivery speed that prevails during a normal operation of the spinning nozzle preceding detection of the yarn flaw.

6. The method according to claim 1 , wherein, during the cleaning process, a yarn is produced having a length-related mass that is greater than the length-related mass of the yarn produced during a normal operation of the spinning nozzle preceding detection of the yarn flaw.

7. The method according to claim 6 , wherein the length-related mass of the yarn produced during the cleaning process is less than 30 Nm.

8. The method according to claim 1 , further comprising performing the cleaning process at defined points in time regardless of detection of a yarn flaw that leads to interruption of yarn production.

9. The method according to claim 1 , further comprising performing the cleaning process at one or all of: (1) a defined period of time has elapsed since the last cleaning process; (2) a predefined minimum length of yarn has been produced; or (3) a predefined minimum quantity of yarn has been produced.

10. The method according to claim 1 , wherein a volume fed flow of the additive is between 0.001 ml/min and 7.0 ml/min.

11. Air jet spinning machine, comprising:
a spinning unit with a spinning nozzle for producing a yarn from a fiber composite fed to the spinning nozzle, the spinning nozzle further comprising;
an inlet for the fiber composite;
an internal vortex chamber;
a yarn formation element protruding into the vortex chamber;
an outlet for the yarn produced inside the vortex chamber with assistance of a vortex air flow;

the spinning unit further comprising:
a sensor system configured to monitor the yarn leaving the outlet during the operation of the spinning unit with regard to defined yarn flaws;
a control unit that interrupts production of the yarn upon detection of a corresponding yarn flaw;
an additive supply allocated to the spinning unit and located such that an additive is supplied to a location either within the spinning nozzle or upstream of the spinning nozzle during operation of the spinning unit;
the control unit further configured to initiate a cleaning process between detection of the specified yarn flaw and interruption of yarn production, during which the additive is fed to the spinning unit by the additive supply; and

wherein the additive is applied to one or all of (1) the fiber composite; (2) the yarn produced from the fiber composite; or (3) parts of the spinning nozzle.

12. The air jet spinning machine according to claim 11 , wherein the control unit is connected to the sensor system and is configured to operate the air jet spinning machine under consideration of measured values transmitted by the sensor system.

Assignees

• Rieter Ag Maschf

Inventors

• Schäffler Gernot
• Hehl Jörg
• Fischer Andreas

Classifications

• D01H4/02 Primary

  imparting twist by a fluid, e.g. air vortex · CPC title

• D01H13/306

  by applying fluids, e.g. steam or oiling liquids · CPC title

• D01H13/32

  Counting, measuring, recording or registering devices · CPC title

• D01H1/115 Primary

  using pneumatic means · CPC title

• D01H13/22

  responsive to presence of irregularities in running material · CPC title