Spinning unit of an air jet spinning machine and its operation

Patent metadata

Field	Value
Publication number	US-9670600-B2
Application number	US-201514710814-A
Country	US
Kind code	B2
Filing date	May 13, 2015
Priority date	May 13, 2014
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A spinning unit is provided for an air jet spinning machine with a spinning nozzle used to manufacture yarn from a fiber strand. The spinning nozzle has an inlet for the fiber strand, a vortex chamber, a yarn forming element protruding into the vortex chamber, and a draw-off channel for the yarn. An additive supply is assigned to the spinning nozzle and designed so that the spinning nozzle is supplied with an additive. The yarn forming element has at least one additive duct that ends in the vortex chamber or the draw-off channel. The additive supply encompasses an additive supply line connected to the additive duct so that an additive introduced into the additive duct via the additive supply line can be introduced into the draw-off channel and/or the vortex chamber. A process for operating an air jet spinning machine with at least one spinning unit is provided. An additive is added, at least intermittently, to the spinning nozzle of the spinning unit while it is operating with the help of an additive supply. The added additive is delivered through an additive duct of the yarn forming element to the draw-off channel and/or the vortex chamber.

First claim

The invention claimed is:

1. A spinning unit for an air jet spinning machine, comprising:
a spinning nozzle configured to manufacture yarn from a fiber strand, the spinning nozzle further comprising:
an inlet for the fiber strand;
an internally located vortex chamber;
a yarn forming element protruding into the vortex chamber and having a yarn draw off channel for the yarn; and
an outlet for the produced yarn;

an additive supply in communication with the spinning nozzle to supply the spinning nozzle with an additive;
the yarn forming element further comprising at least one additive duct defined therein that ends in the vortex chamber or the draw off channel, the additive duct oriented obliquely relative to a transport direction of the yarn through the draw off channel; and
the additive supply further comprising at least one additive supply line that is fluidically connected to the additive duct, so that an additive introduced through the additive supply line into the additive duct is introduced into one or both of the draw off channel or the vortex chamber.

2. The spinning unit according to claim 1 , wherein the additive duct comprises a bore that runs inside the yarn forming element.

3. The spinning unit according to claim 2 , wherein the additive duct defines an angle (a) with an axis of the draw-off channel between 3° and 12°.

4. The spinning unit according to claim 2 , wherein the additive duct ends in the draw-off channel adjacent to a fiber inlet opening in the yarn forming element.

5. The spinning unit according to claim 2 , characterized in that the additive duct ends in an outer surface of a wall of the yarn forming element that surrounds the draw-off channel.

6. The spinning unit according to claim 1 , characterized in that the additive duct is also fluidically connected with a compressed air line so that compressed introduced air introduced via the compressed air line is introduced into one or both of the draw-off channel or the vortex chamber through the additive duct.

7. The spinning unit according to claim 6 , further comprising a valve in either of the compressed air line or the additive supply line, the valve settable between two different valve positions such that the additive duct is fluidically connected either to the compressed air line or the additive supply fine depending on the position of the valve.

8. The spinning unit according to claim 7 , wherein the valve is connected to a control mechanism designed to keep the valve, during spinning operation of the spinning unit, in a first valve position in which the additive duct is fluidically connected to the additive supply line, and to keep the valve, during a piecing process of the spinning unit, in a second valve position in which the additive duct is fluidically connected to the compressed air line.

9. A process for operating an air jet spinning machine with at least one spinning unit having a spinning nozzle, comprising:
feeding a fiber strand to the spinning nozzle via an inlet while the spinning unit is operated;
imparting a twist to the fiber strand proximate to a yarn forming element that protrudes into a vortex chamber of the spinning nozzle, wherein a yarn is formed from the fiber strand and exits the spinning nozzle through a draw-off channel of the yarn forming element;
with an additive supply, feeding an additive to the spinning nozzle while the spinning unit is operated; and
wherein the additive is fed through an additive duct defined in the yarn forming element and is delivered in one or both of the draw-off channel or the vortex chamber, the additive duct oriented obliquely relative to a transport direction of the yarn through the draw off channel.

10. The process according to claim 9 , wherein an additive is delivered through the additive duct during a spinning process of the spinning unit, and compressed air is delivered through the additive duct during a piecing process of the spinning unit.

11. The process according to claim 10 , wherein the additive duct is fluidically connected to an additive supply line and a compressed air line, and a valve is assigned to one of the additive supply line or the compressed air line, wherein the valve is controlled in a first position during the spinning process in which the additive duct is connected to the additive supply line, and wherein the valve is controlled in a second position during the piecing process in which the additive duct is connected to the compressed air line.

12. The process according to claim 9 , wherein volumetric or mass flow of the additive delivered via the additive duct is regulated with a dosing device.

13. The process according to claim 12 , wherein the volumetric flow of the delivered additive reaches a rate between 0.001 mlmL/min and 7.0 mL/min, or mass flow of the delivered additive reaches a rate between 0.001 g/min and 7.0 g/min.

14. The process according to claim 13 , wherein the volumetric flow of the additive delivered while the spinning unit is operating in a spinning process reaches a rate between 0.001 mL/min and 1.5 mL/min, and the volumetric flow of the additive added while the spinning unit is being cleaned reaches a rate between 2.0 mL/min and 7.0 mL/min.

15. The process according to claim 13 , wherein the mass flow of the additive delivered while the spinning unit is operating in a spinning process reaches a rate between 0.001 g/min and 1.5 g/min, and the mass flow of the additives added while the spinning unit is being cleaned reaches a rate between 2.0 g/min and 7.0 g/min.

Assignees

• Rieter Ag Maschf

Inventors

• Schäffler Gernot
• Hehl Jörg
• Fischer Andreas

Classifications

• D01H4/34

  using air-jet streams · CPC title

• D01H13/306

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

• D01H1/115 Primary

  using pneumatic means · CPC title

• D01H4/08

  Rotor spinning, i.e. the running surface being provided by a rotor · CPC title

• D01H4/02 Primary

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