Dunnage conversion machine jam-detection system and method

Patent metadata

Field	Value
Publication number	US-2016101585-A1
Application number	US-201414891512-A
Country	US
Kind code	A1
Filing date	May 16, 2014
Priority date	May 16, 2013
Publication date	Apr 14, 2016
Grant date	—

Abstract

A jam-sensing method for a dunnage conversion machine includes the following steps: (a) converting a stock material into a relatively less dense dunnage material having characteristics that vary along the length of the dunnage material; (b) sensing the characteristics of the dunnage material; (c) generating a signal that varies as a function of the sensed characteristics; (d) monitoring the generated signal over time; and (e) generating a control signal when variation in the generated signal within a predetermined period is less than a predetermined amount, which would indicate a lack of movement of the material. This control signal can used to shut down the conversion process, thereby minimizing the extent of the jam condition.

First claim

1 . A method for detecting longitudinal movement of a material having a varying surface profile, comprising the steps of:
sensing the profile of a surface of a continuous strip of material having a variable surface profile;
generating a signal that varies as a function of the sensed profile;
monitoring the varying signal over time; and
generating a control signal when variation in the signal within a predetermined

period is less than a predetermined amount, which would indicate a lack of movement of the material.

2 . A method as set forth in claim 1 , where the sensing step includes sensing the profile of a strip of material.

3 . A method as set forth in claim 1 , where the sensing step includes contactlessly sensing the surface profile.

4 . A method of making a dunnage material, comprising the method of claim 1 , and the step of converting a sheet material into a relatively less dense dunnage material having a nonplanar surface with a variable surface profile, where the sensing step includes the step of sensing the surface profile of the nonplanar surface of the dunnage material.

5 . A method as set forth in claim 4 , where the converting step includes randomly crumpling the sheet material to form a dunnage material having a randomly variable surface profile.

6 . A method as set forth in claim 4 , comprising the step of feeding a sheet stock material from a supply.

7 . A method as set forth in claim 6 , where the feeding step includes feeding a sheet of paper from the supply.

8 . A method as set forth in claim 4 , comprising the step of stopping the converting step if the monitoring step detects no motion.

9 . A method as set forth in claim 1 , comprising the step of positioning a sensor relative to a path of the material to sense the variable-contour surface of the dunnage material traveling on the path.

10 . A method as set forth in claim 1 , wherein the sensing step includes directing a light source against the surface of the dunnage material and using a sensor to detect light reflected from the surface.

11 . A method as set forth in claim 1 , where the monitoring step includes resetting a timer in response to a change in the produced signal.

12 . A dunnage conversion machine, comprising
a conversion assembly for converting a sheet material into a relatively less dense dunnage material having a nonplanar surface with a longitudinally variable profile and longitudinally advancing the dunnage material along a path; and a sensor adjacent the path that is configured to sense the profile of the surface of the dunnage material on the path and to produce a corresponding signal that varies as a function of the sensed surface profile of the dunnage material; and a controller configured to monitor the signal produced by the sensor for changes over time to detect longitudinal motion of the dunnage material, and to generate a control signal when variation in the signal within a predetermined period is less than a predetermined amount, which would indicate a lack of movement of the material, the controller being in communication with the conversion assembly so that the controller can stop the conversion assembly in response to the control signal.

13 . A dunnage conversion machine as set forth in claim 12 , comprising a supply of sheet material that includes paper.

14 . A dunnage conversion machine as set forth in claim 12 , where the conversion assembly includes at least two rotating members arranged to draw the sheet material from the supply.

15 . A dunnage conversion machine as set forth in claim 14 , where the conversion assembly includes at least two sets of rotating members, including a first set located downstream of a second set, and the first set drawing the sheet material thereby at a first rate and the second set drawing the sheet material thereby at a second rate that is greater than the first rate such that the sheet material randomly crumples as the sheet material travels from the first set to the second set.

16 . A dunnage conversion machine as set forth in claim 12 , where the conversion assembly randomly crumples the stock material to produce a dunnage material with a randomly crumpled surface profile.

17 . A dunnage conversion machine as set forth in claim 12 , where the sensor is a photosensor.

18 . A dunnage conversion machine as set forth in claim 12 , where the sensor includes a light source.

19 . A dunnage conversion machine as set forth in claim 12 , where the controller includes a processor and a memory.

20 . A method for identifying a jam state in a dunnage conversion machine, comprising the steps of:
converting a stock material into a relatively less dense dunnage material having characteristics that vary along the length of the dunnage material; sensing the characteristics of the dunnage material; generating a signal that varies as a function of the sensed characteristics; monitoring the generated signal over time; and
generating a control signal when variation in the generated signal within a predetermined period is less than a predetermined amount, which would indicate a lack of movement of the material.

Assignees

• Ranpak Corp

Inventors

• Park Kevin W
• Fischer Roger G

Classifications

• B31D5/0043

  including crumpling flat material · CPC title

• B31D2205/0088

  Control means · CPC title

• B31D5/0047 Primary

  involving toothed wheels · CPC title