Electronic control of metered film dispensing in a wrapping apparatus

Patent metadata

Field	Value
Publication number	US-9725195-B2
Application number	US-34992909-A
Country	US
Kind code	B2
Filing date	Jan 7, 2009
Priority date	Jan 7, 2008
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

An apparatus for wrapping a load may include a film dispenser for dispensing a film web including a film dispensing drive. The apparatus may also include a rotational drive system for providing relative rotation between the load and the dispenser during a wrapping cycle. The apparatus may further include a controller configured to operatively couple the film dispensing drive and the rotational drive system such that, for any portion of a revolution of the film dispenser relative to the load during the wrapping cycle, the film dispenser dispenses a selected length of the film web corresponding to the portion of the revolution.

First claim

What is claimed is:

1. An apparatus for wrapping a load, comprising:
a film dispenser for dispensing a film web, wherein the film dispenser is driven by a film dispensing drive configured to rotate at least one film dispenser roller of the film dispenser;
a rotational drive system for providing relative rotation between the load and the dispenser;
a sensor sensing a parameter related to demand for the film web at the load; and
a controller determining demand in response to the sensed parameter, operatively coupling the film dispensing drive and the rotational drive system, and establishing a ratio between operation of the film dispensing drive and the rotational drive system such that, for at least a portion of a relative revolution between the film dispenser and the load, the film dispenser dispenses a length of the film web based on the determined demand for the film web at the load during the at least a portion of a relative revolution.

2. The apparatus of claim 1 , wherein the controller is configured to operatively couple by simulating a connection between the film dispensing drive and the rotational drive system.

3. The apparatus of claim 1 , wherein the demand corresponds to a length of the load traversed by the film dispenser during the at least a portion of a relative revolution.

4. The apparatus of claim 1 , wherein the at least a portion of a relative revolution includes a full relative revolution, and the demand is based, at least in part, on a girth of the load.

5. The apparatus of claim 1 , further comprising a first variable frequency drive for controlling the film dispensing drive.

6. The apparatus of claim 5 , further comprising a second variable frequency drive for controlling the rotational drive system.

7. The apparatus of claim 6 , wherein the controller is configured to simulate a connection between the first and second variable frequency drives.

8. The apparatus of claim 1 , wherein the sensor comprises an idle roller.

9. The apparatus of claim 8 , wherein the idle roller is downstream of the film dispenser.

10. The apparatus of claim 8 , wherein the controller is configured to identify demand based, at least in part, on rotation of the idle roller.

11. The apparatus of claim 8 , wherein the idle roller is configured to respond to a change in demand.

12. The apparatus of claim 11 , wherein the controller is configured to vary the length of the film web dispensed based on the response of the idle roller to the change in demand.

13. The apparatus of claim 8 , wherein the controller is configured to identify a film break based on a speed or direction of rotation of the idle roller.

14. The apparatus of claim 8 , wherein the controller is configured to:
compare an actual speed of the idle roller to an expected speed of the idle roller; and
stop the rotational drive system if the actual speed differs from the expected speed by a threshold amount.

15. The apparatus of claim 1 , wherein the controller is configured to operate the dispensing drive and the rotational drive system at a first ratio during a first portion of a wrapping cycle, and at a second ratio during a second portion of the wrapping cycle.

16. The apparatus of claim 15 , wherein the controller is configured to operate the dispensing drive and the rotational drive system at a third ratio during a third portion of the wrapping cycle, wherein at least one of the first, second, and third ratios is different from the others of the first, second, and third ratios.

17. The apparatus of claim 16 , wherein the first portion is a start-up portion of the wrapping cycle, the second portion is a primary portion of the wrapping cycle, and the third portion is an end portion of the wrapping cycle.

18. An apparatus for wrapping a load, comprising:
a film dispenser for dispensing a film web, wherein the dispenser is driven by a film dispensing drive configured to rotate at least one film dispenser roller of the film dispenser;
a rotational drive system for providing relative rotation between the load and the dispenser; and
a controller:
setting a length of the film web to be dispensed for at least a portion of a relative revolution between the dispenser and the load based on demand for the film web at the load;
driving the rotational drive system and the dispensing drive at a ratio at which the dispenser dispenses the set length of the film web for the at least a portion of a relative revolution;
further comprising an idle roller; and,
wherein the demand is identified based at least in part on rotation of the idle roller.

19. The apparatus of claim 18 , wherein the demand for the film web at the load is based at least in part on a length of the load traversed by the film dispenser during the at least a portion of a relative revolution.

20. The apparatus of claim 18 , wherein the at least a portion of a relative revolution includes a full relative revolution, and the demand for the film web at the load is based at least in part on a girth of the load.

21. The apparatus of claim 18 , further comprising a first variable frequency drive for controlling the film dispensing drive.

22. The apparatus of claim 21 , further comprising a second variable frequency drive for controlling the rotational drive system.

23. The apparatus of claim 22 , wherein the controller is configured to simulate a connection between the first and second variable frequency drives.

24. The apparatus of claim 18 , wherein the idle roller is positioned downstream of the film dispenser.

25. The apparatus of claim 18 , wherein the idle roller is configured to respond to a change in demand.

26. The apparatus of claim 25 , wherein the controller is configured to identify the change in the demand based on the response of the idle roller to the change in demand.

27. The apparatus of claim 18 , wherein the controller is configured to identify a film break based on rotation of the idle roller.

28. The apparatus of claim 18 , wherein the controller is configured to:
compare an actual speed of the idle roller to an expected speed of the idle roller; and
stop the rotational drive system if the actual speed differs from the expected speed by a selected amount.

29. The apparatus of claim 18 , wherein the ratio at which the controller is configured to drive the rotational drive system and the dispensing drive that will result in the dispenser dispensing the set length of the film web is a first ratio, and wherein the controller is also configured to operate the dispensing drive and the rotational drive system at a second ratio.

30. The apparatus of claim 29 , wherein the controller is configured to operate the dispensing drive and the rotational drive system at a third ratio, wherein at least one of the first, second, and third ratios is different from the others of the first, second, and third ratios.

31. The apparatus of claim 30 , wherein the controller is configured to operate the dispensing drive and the rotational drive system at the first ratio during a primary portion of a wrapping cycle, at the second ratio during a start-up portion of the wrapping cycle, and at the third ratio during an end portion of the wrapping cycle.

32. An apparatus for wrapping film around a load, the apparatus comprising:
a film dispenser configured to dispense f

Assignees

• Lancaster P R Iii
• Janes Sr Robert D
• Mitchell Michael
• Harris Thomas
• Johnson Richard L
• Lantech Com Llc

Inventors

• Lancaster Iii Patrick R
• Janes Sr Robert D
• Mitchell Michael
• Harris Thomas
• Johnson Richard L

Classifications

• B65B2210/20

  the web dispenser being mounted on a rotary arm · CPC title

• B65B11/025 Primary

  by webs revolving around stationary articles · CPC title

• B65B11/045

  by rotating platforms supporting the articles · CPC title

• B65B2011/002

  Prestretching mechanism in wrapping machines · CPC title

• B65B2210/18

  the web dispenser being mounted on a rotary ring · CPC title