Spinning unit of an air jet spinning machine and the operation of such a machine

Patent metadata

Field	Value
Publication number	US-9719192-B2
Application number	US-201514813968-A
Country	US
Kind code	B2
Filing date	Jul 30, 2015
Priority date	Jul 30, 2014
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

A method and system for operating an air jet spinning machine, that features at least one spinning unit with one spinning nozzle for producing a yarn. During normal operation of the spinning unit, a fiber composite is fed to the spinning nozzle through an inlet and 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, which leaves the spinning nozzle through an outlet. After an interruption in yarn production, a piecing process is carried out, with which one yarn end on the spool side moves counter to the transport direction through the spinning nozzle, is overlaid with one end of the fiber composite after passing through the spinning nozzle and, together with this, is brought through the inlet into the spinning nozzle. After conclusion of the piecing process, the production of yarn is continued through the resumption of normal operation. During the piecing process, at least temporarily, additive is applied at the end of the fiber composite.

First claim

The invention claimed is:

1. A method for operating an air jet spinning machine, wherein the air jet spinning machine features at least one spinning unit with a spinning nozzle for producing a yarn, the method comprising:
during normal 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, the yarn leaving the spinning nozzle through an outlet;
spooling the yarn on a sleeve with assistance of a spooling device;
carrying out a piecing process after an interruption in the yarn production wherein a yarn end from a spool side of the spinning nozzle is moved counter to the transport direction through the spinning nozzle, is overlaid with an end of the fiber composite after passing through the spinning nozzle, the overlaid yarn end and fiber composite end brought through the inlet into the spinning nozzle;
during the piecing process, applying an additive to the end of the fiber composite; and
after conclusion of the piecing process, resuming production of the yarn in the normal operation.

2. The method according to claim 1 , wherein the additive is applied at the end of the fiber composite after it has been overlaid with the yarn end.

3. The method according to claim 2 , wherein the additive is applied in front of the inlet of the spinning nozzle viewed in the transport direction.

4. The method according to claim 1 , wherein a volume flow of the fed additive during the piecing process is between 0.001 ml/min and 2.0 ml/min, or a mass flow of the fed additive during the piecing process is between 0.001 g/min and 2.0 g/min.

5. The method according to claim 4 , wherein during the addition of additive, the volume flow or mass flow of the additive is regulated with assistance of a valve that is opened and closed at least once per second such that the additive fed to the valve passes through the valve in a pulse-like manner.

6. The method according to claim 4 , wherein during the piecing process, the volume flow or mass flow of the additive is higher than that during the normal operation of the spinning unit following the piecing process.

7. The method according to claim 4 , wherein during the piecing process, the volume flow or mass flow of the additive is reduced compared to an initial amount at start of the piecing operation.

8. The method according to claim 7 , wherein the reduction of the volume flow or mass flow of the additive is continuous through the piecing operation.

9. An 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 comprising an inlet for the fiber composite;
an internal vortex chamber defined in the spinning nozzle;
a yarn formation element protruding into the vortex chamber;
an outlet for the yarn produced in the vortex chamber with assistance of a vortex air flow generated in the vortex chamber;
an additive supply allocated to the spinning unit and configured to apply an additive at an end of the fiber composite present after an interruption in the yarn production;
a control unit in operative connection with the additive supply and configured to, after an interruption in yarn production, initiate a piecing process wherein additive is applied at the end of the fiber composite.

10. The air jet spinning machine according to claim 9 , wherein the additive supply further comprises a feed valve, the control unit in operative connection with the feed valve to regulate a volume flow of the additive during the piecing process is between 0.001 ml/min and 2.0 ml/min, or a mass flow of the additive during the piecing process is between 0.001 g/min and 2.0 g/min, wherein the valve is further opened and closed at least once per second such that the additive fed to the valve passes through the valve in a pulse-like manner.

Assignees

• Rieter Ag Maschf

Inventors

• Kübler Markus
• Schäffler Gernot
• Widmann Martin

Classifications

• D01H4/02 Primary

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

• D01H2700/21

  Piecing or cleaning in spinning mules · CPC title

• D01H13/306

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

• D01H1/115 Primary

  using pneumatic means · CPC title