Sheet feeding device and sheet feeding method

Patent metadata

Field	Value
Publication number	US-11597618-B2
Application number	US-202017429409-A
Country	US
Kind code	B2
Filing date	Feb 12, 2020
Priority date	Feb 13, 2019
Publication date	Mar 7, 2023
Grant date	Mar 7, 2023

Abstract

In steady control, a shaft control unit (922) adjusts rotation speed of a first support shaft (31) to cause a first roll (R1) to have peripheral speed equal to predetermined conveyance speed by maintaining a sheet storage amount in a storage mechanism (5) in a first storage amount as a reference. In storage amount adjustment control, the shaft control unit (922) accelerates the rotation speed of the first support shaft (31) to increase the peripheral speed of the first roll (R1) higher than the conveyance speed, until the sheet storage amount in the storage mechanism (5) reaches a predetermined second storage amount that is larger than the first storage amount. A calculation unit (911) calculates an outer diameter of the first roll (R1) based on the conveyance speed when the steady control is performed, and calculates the outer diameter of the first roll (R1) based on the sheet thickness calculated from a decrease amount of the outer diameter of the first roll (R1) in the steady control when the storage amount adjustment control is performed.

First claim

The invention claimed is:

1. A sheet feeding device that sequentially feeds a sheet from each of a first roll and a second roll around which the sheet is wound, and supplies the sheet to a predetermined processing device at predetermined conveyance speed using a supply mechanism, the sheet feeding device comprising:
a first support shaft that is rotatable while supporting the first roll at its center position;
a second support shaft that is rotatable while supporting the second roll at its center position;
the supply mechanism that supplies the sheet fed from the first roll or the second roll as the first support shaft or the second support shaft rotates to the processing device at the predetermined conveyance speed;
a storage mechanism that is disposed upstream of the supply mechanism to store the sheet fed from the first roll or the second roll, and is configured to be able to change a sheet storage amount;
a joining mechanism that is disposed upstream of the storage mechanism, and is capable of switching a roll of sheet to be supplied to the processing device by performing joining processing of joining the sheet of the first roll and the sheet of the second roll;
a calculation unit that calculates an outer diameter of the first roll or the second roll and a sheet remaining amount that change as the sheet is supplied to the processing device by the supply mechanism; and
a shaft control unit that controls rotation operation of the first support shaft and the second support shaft,
wherein when the sheet of the second roll is continuously supplied after the sheet of the first roll is supplied to the processing device,
the shaft control unit
performs steady control of adjusting rotation speed of the first support shaft to cause the first roll to have peripheral speed equal to conveyance speed by maintaining the storage amount of the sheet of the first roll in a first storage amount as a reference using the storage mechanism in a steady state in which the sheet of the first roll is supplied to the processing device at the conveyance speed, and
performs storage amount adjustment control of, when the sheet remaining amount of the first roll becomes a first remaining amount obtained by adding a predetermined length to a predetermined target remaining amount, accelerating the rotation speed of the first support shaft to cause the first roll to have the peripheral speed faster than the conveyance speed until the storage amount of the sheet of the first roll using the storage mechanism reaches a predetermined second storage amount that is larger than the first storage amount, and after the storage amount of the first roll reaches the second storage amount, adjusting the rotation speed of the first support shaft to cause the first roll to have the peripheral speed equal to the conveyance speed,
the joining mechanism performs the joining processing when the sheet remaining amount of the first roll reaches the target remaining amount after the shaft control unit performs the storage amount adjustment control, and
the calculation unit
calculates a first outer diameter as the outer diameter of the first roll based on the conveyance speed and a number of rotations of the first support shaft, and calculates a sheet thickness from a decrease amount of the first outer diameter per rotation of the first roll, to calculate the sheet remaining amount based on the first outer diameter of the first roll and the sheet thickness, when the shaft control unit performs the steady control, and
calculates a second outer diameter as the outer diameter of the first roll based on the first outer diameter immediately before switching to the storage amount adjustment control, the calculated sheet thickness, and the number of rotations of the first support shaft, to calculate the sheet remaining amount based on the second outer diameter of the first roll and the sheet thickness, when the shaft control unit performs the storage amount adjustment control.

2. The sheet feeding device according to claim 1 , wherein
the shaft control unit performs stop control of stopping rotation of the first support shaft to join the sheet of the first roll to the sheet of the second roll by the joining processing using the joining mechanism with the sheet of the first roll being in the target remaining amount, when the sheet remaining amount of the first roll reaches a predetermined second remaining amount that is smaller than the first remaining amount after the storage amount adjustment control is performed.

3. The sheet feeding device according to claim 2 , wherein
the first remaining amount is set to a value obtained by adding, to the target remaining amount, a first management length obtained by adding a length of a sheet supplied from the supply mechanism to the processing device while the shaft control unit performs the storage amount adjustment control and the second storage amount, and a second management length that is a feeding length of a sheet fed from the first roll while the shaft control unit performs the stop control, and
the second remaining amount is set to a value obtained by adding the second management length to the target remaining amount.

4. A sheet feeding method of sequentially feeding a sheet from each of a first roll supported by a first support shaft and a second roll supported by a second support shaft as the first support shaft or the second support shaft rotates, and supplying the sheet to a predetermined processing device at predetermined conveyance speed, the sheet feeding method comprising:
a steady supply step of supplying the sheet to the processing device while adjusting rotation speed of the first support shaft to cause the first roll to have peripheral speed equal to the conveyance speed by maintaining the sheet fed from the first roll in a first storage amount as a reference upstream of the processing device;
a storage amount adjusting step of accelerating the rotation speed of the first support shaft, until a storage amount of the sheet of the first roll upstream of the processing device reaches a predetermined second storage amount that is larger than the first storage amount, to cause the first roll to have the peripheral speed faster than the conveyance speed, when a sheet remaining amount of the first roll that changes as the sheet is supplied to the processing device becomes a first remaining amount obtained by adding a predetermined length to a predetermined target remaining amount, and adjusting the rotation speed of the first support shaft to cause the first roll to have the peripheral speed equal to the conveyance speed after the storage amount of the sheet of the first roll reaches the second storage amount; and
a joining processing step of performing joining processing in which the sheet of the first roll is joined to the sheet of the second roll with the sheet remaining amount of the first roll, becoming the predetermined target remaining amount, to switch a roll of the sheet to be supplied to the processing device from the first roll to the second roll,
wherein in the steady supply step, a first outer diameter is calculated as an outer diameter of the first roll based on the conveyance speed and a number of rotations of the first support shaft, and a sheet thickness is calculated from a decrease amount of the first outer diameter per rotation of the first roll, to calculate the sheet remaining amount based on the first outer diameter of the first roll and the sheet thickness, and
in the storage amount adjusting step, a second outer diameter is calculated as the outer diameter of the first roll based on the first outer diameter immediately before shifting to the storage amount adjusting step, the calculated sheet thickness, and the number of rotations of the first support shaft, to calculate the sheet remaining amount based on

Assignees

• Zuiko Corp

Inventors

• HIROYASU Masato

Classifications

• B65H2513/51

  Sequence of process · CPC title

• B65H2601/511

  Waste of handled material · CPC title

• B65H2511/114

  Remaining length of web roll · CPC title

• B65H2511/14

  Diameter, e.g. of roll or package · CPC title

• B65H2557/63

  Optimisation, self-adjustment, self-learning processes or procedures, e.g. during start-up · CPC title