Method for automatically piecing a thread at a workstation of a textile machine, and textile machine

Patent metadata

Field	Value
Publication number	US-10907278-B2
Application number	US-201916244466-A
Country	US
Kind code	B2
Filing date	Jan 10, 2019
Priority date	Jan 16, 2018
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

A method for automatically piecing a thread at a workstation of a textile machine, includes seeking an end of the thread on a surface of a bobbin with a suction nozzle and unwinding the thread from the bobbin counter to a regular draw-off direction of the thread and sucking the thread into the suction nozzle. The bobbin is driven in a direction of reverse rotation with a drive. A thread loop is draw-opened in the thread and moved towards a piecing unit via movement of a feeder unit. The bobbin is driven in the direction of reverse rotation during the drawing-open of the thread loop such that the thread is unwound from the bobbin. A speed of reverse rotation of the bobbin is coordinated with movement of the feeder unit.

First claim

The invention claimed is:

1. A method for automatically piecing a thread at a workstation of a textile machine, comprising:
seeking an end of the thread on a surface of a bobbin with a suction nozzle;
unwinding the thread from the bobbin counter to a regular draw-off direction of the thread and sucking the thread into the suction nozzle;
driving the bobbin in a direction of reverse rotation with a drive for the unwinding of the thread;
draw-opening a thread loop in the thread and moving the thread loop towards a piecing unit via movement of a feeder unit;
driving the bobbin in the direction of reverse rotation during the drawing-open of the thread loop such that the thread is unwound from the bobbin;
coordinating a speed of the reverse rotation of the bobbin with movement of the feeder unit; and
wherein the reverse rotation speed of the bobbin is coordinated such that at all time during the reverse rotation of the bobbin, a thread length withdrawn from the bobbin is less than a thread length required for forming the thread loop.

2. The method as in claim 1 , wherein the reverse rotation speed of the bobbin is coordinated such that a thread length withdrawn from the bobbin is made available synchronously to the thread length required for forming the thread loop.

3. A method for automatically piecing a thread at a workstation of a textile machine, comprising:
seeking an end of the thread on a surface of a bobbin with a suction nozzle;
unwinding the thread from the bobbin counter to a regular draw-off direction of the thread and sucking the thread into the suction nozzle;
driving the bobbin in a direction of reverse rotation with a drive for the unwinding of the thread;
draw-opening a thread loop in the thread and moving the thread loop towards a piecing unit via movement of a feeder unit;
driving the bobbin in the direction of reverse rotation during the drawing-open of the thread loop such that the thread is unwound from the bobbin; and
coordinating a speed of the reverse rotation of the bobbin with movement of the feeder unit; and
wherein the reverse rotation speed of the bobbin is coordinated such that at all time during the reverse rotation of the bobbin, a thread length withdrawn from the bobbin is greater than a thread length required for forming the thread loop.

4. The method as in claim 1 , wherein the drive is driven according to a speed profile during movement of the feeder unit.

5. The method as in claim 1 , further comprising measuring a tensile force of the thread during movement of the feeder unit and controlling the drive according to the measured tensile force.

6. A textile machine comprising a workstation, the workstation further comprising:
a suction nozzle for seeking an end of a thread on a surface of a bobbin and sucking in the thread;
a drive configured to drive the bobbin such that the thread is withdrawn from the bobbin counter to a regular draw-off direction of the thread;
a piecing unit;
a feeder unit configured to drawn-open a thread loop in the thread withdrawn from the bobbin and move the thread loop towards the piecing unit, the feeder unit pivotably arranged at the workstation to account for a varying speed of the yarn transported by the feeder unit during movement of the feeder unit;
a controller configured for operating the drive in a direction of reverse rotation during the draw-opening of the thread loop such that the thread is unwound from the bobbin and a speed of the reverse rotation of the bobbin is tied with movement of the feeder unit; and
wherein the reverse rotation speed of the bobbin is controlled such that at all time during the reverse rotation of the bobbin, a thread length withdrawn from the bobbin is less than a thread length required for forming the thread loop.

7. The textile machine as in claim 6 , wherein the drive and the feeder unit are situated at the workstation.

8. The textile machine as in claim 6 , wherein the feeder unit moves in a pivoting motion.

9. The textile machine as in claim 6 , further comprising a measuring unit disposed to measure a tensile force of the thread sucked into the nozzle.

10. A method for automatically piecing a thread at a workstation of a textile machine, comprising:
seeking an end of the thread on a surface of a bobbin with a suction nozzle;
unwinding the thread from the bobbin counter to a regular draw-off direction of the thread and sucking the thread into the suction nozzle;
driving the bobbin in a direction of reverse rotation with a drive for the unwinding of the thread;
draw-opening a thread loop in the thread and moving the thread loop towards a piecing unit via movement of a feeder unit;
driving the bobbin in the direction of reverse rotation during the drawing-open of the thread loop such that the thread is unwound from the bobbin; and
coordinating a speed of the reverse rotation of the bobbin with movement of the feeder unit; and
wherein the drive is driven according to a speed profile during movement of the feeder unit.

Assignees

• Rieter Ag Maschf

Inventors

• Bahlmann Bernd
• Pohn Romeo
• Brandl Sebastian
• Maleck Mario
• Baier Frank
• Hagl Robert
• Gruber Thomas
• Wein Robin
• Kettner Christian
• Hoyer Andreas

Classifications

• B65H67/085 Primary

  end-finding at the take-up package, e.g. by suction and reverse package rotation · CPC title

• B65H2701/31

  Textiles threads or artificial strands of filaments · CPC title

• D01H13/104

  Regulating tension by devices acting on running yarn and not associated with supply or take-up devices · CPC title

• D01H13/1691 Primary

  Thread breakage detector means associated with pneumatic cleaning devices, e.g. suction of broken end of yarn · CPC title

• D05B57/26

  Bobbin holders or casings; Bobbin holder or case guards; Bobbin discharge devices · CPC title