Shredder throat safety system

• US 20060054725A1
• Filed: 07/11/2005
• Published: 03/16/2006
• Est. Priority Date: 09/10/2004
• Status: Active Grant

• Current Assignee: Fellowes Incorporated
• Original Assignee: Fellowes Incorporated
• Inventors: Matlin, Tai Hoon Kim
• Granted Patent: US 7,661,614 B2
• Time in Patent Office: Days
• US Class Current: 241/37.500
• CPC Class Codes: B02C 18/0007 specially adapted for disintegrating documents
• CPC Class Codes: B02C 2018/0015 for disintegrating CDs, DVDs and/or credit cards
• CPC Class Codes: B02C 2018/164 Prevention of jamming and/or overload
• CPC Class Codes: B02C 2018/168 User safety devices or measures in shredders
• CPC Class Codes: B02C 23/04 Safety devices in general F16P ; for rotary mills B02C13/31
• CPC Class Codes: F16P 3/141 using sound propagation, e.g. sonar
• CPC Class Codes: F16P 3/145 using magnetic technology
• CPC Class Codes: F16P 3/147 using electro-magnetic technology, e.g. tags or radar
• CPC Class Codes: F16P 3/148 using capacitive technology

Abstract

The present invention relates to a shredder that includes a housing having a movable part that forms at least a part of an opening for the insertion of articles to be fed into the shredder. A detector detects motion of the movable part, and in response, a controller performs a predetermined operation, including, for example, stopping cutting elements of the shredder mechanism.

Claims

1. A shredder comprising:

a housing;

a shredder mechanism received in the housing and including an electrically powered motor and cutter elements, the shredder mechanism enabling articles to be shredded to be fed into the cutter elements and the motor being operable to drive the cutter elements so that the cutter elements shred the articles fed therein;

the housing having a movable part providing at least part of an opening enabling articles to be fed therethrough into the cutter elements of the shredder mechanism for shredding, the movable part being movable from a first position to a second position and being biased to the first position;

a detector configured to detect movement of the movable part to the second position;

the movable part being constructed to move from the first position to the second position upon a user attempting to force an article having a thickness greater than a predetermined thickness through the opening; and

a controller operable to perform a predetermined operation responsive to the detector detecting that the movable part has moved to the second position.

2. A shredder according to claim 1, wherein the detector comprises a switch that is actuated in response to the movable part moving to the second position.

3. A shredder according to claim 1, wherein the predetermined operation is illuminating an indicator.

4. A shredder according to claim 1, wherein the predetermined operation is sounding an alarm indicator.

5. A shredder according to claim 1, wherein the predetermined operation is stopping the cutter elements.

6. A shredder according to claim 1, wherein the controller comprises a microcontroller.

7. A shredder according to claim 1, wherein at least a portion of a wall of the opening is moveable in response to pressure of an inserted article having a thickness greater than the predetermined thickness, thereby triggering the detector.

8. A shredder according to claim 7, wherein the portion moves outwardly in response to the pressure.

9. A shredder according to claim 7, wherein the portion moves downwardly in response to the pressure.

10. A shredder according to claim 7, wherein the portion is spring biased towards an upward position and in response to the insertion of the article having a thickness greater than the predetermined thickness, the portion is pushed downward to actuate the switch.

11. A shredder according to claim 10, wherein the portion includes a plunger.

12. A shredder according to claim 10, wherein the shredder comprises a switch that is actuated by the plunger as the movable part moves to the second position.

13. A shredder according to claim 2, wherein the switch is a foil switch.

14. A shredder according to claim 2, wherein the switch is a lever switch.

15. A shredder according to claim 1, wherein the detector comprises a mechanical switch.

16. A shredder according to claim 1, wherein the detector comprises an optical detector.

17. A shredder according to claim 1, wherein the detector comprises a strain gauge configured and arranged to measure a movement of the movable part.

18. A shredder comprising:

a housing;

a shredder mechanism received in the housing and including an electrically powered motor and cutter elements, the shredder mechanism enabling articles to be shredded to be fed into the cutter elements and the motor being operable to drive the cutter elements so that the cutter elements shred the articles fed therein;

the housing having an opening enabling articles to be fed therethrough into the cutter elements of the shredder mechanism for shredding;

a resistive switch, at least in part located adjacent the opening and configured to indicate the presence of a person or animal in contact with the switch; and

a controller operable to perform a predetermined operation responsive to the indicated presence of the person or animal.

19. A shredder according to claim 18, wherein the predetermined operation is illuminating an indicator.

20. A shredder according to claim 18, wherein the predetermined operation is sounding an alarm indicator.

21. A shredder according to claim 18, wherein the predetermined operation is stopping the cutter elements.

22. A shredder according to claim 18, wherein the resistive switch further comprises a pair of electrically isolated conductive elements that, when simultaneously contacted by a part of the person or animal, are in electrical communication.

23. A shredder according to claim 18, wherein the controller is configured to monitor changes in signal strength from the switch over time, and to adjust a threshold value for performing the predetermined operation.

24. A shredder according to claim 18, wherein the controller is configured to perform the predetermined operation based at least in part on a rate of change of a monitored resistance of the resistive switch.

25. A shredder according to claim 18, wherein the controller is configured to perform the predetermined operation based at least in part on a monitored resistance of the resistive switch.

26. A device for use with a shredder, the shredder including a housing having an opening enabling articles to be fed therethrough into cutter elements of a shredder mechanism for shredding, the device comprising:

a switch, affixable to a portion of a shredder proximate the opening and configured to indicate the presence of a person or animal in contact with the switch;

a controller, in electrical communication with the switch, the controller having a connector constructed and arranged to engage a power supply and a receptacle constructed and arranged to accept a power cord of the shredder, the controller further being configured to provide power from the power supply to the shredder and to stop providing power to the shredder responsive to the indicated presence of the person or animal.

27. A device as in claim 26, wherein the switch is removably affixable to the shredder.

28. A device as in claim 26, wherein the switch is a capacitive switch.

29. A device as in claim 26, wherein the switch is a resistive switch.

30. A device as in claim 26, wherein the switch is a mechanical switch.

31. A device as in claim 30, wherein the mechanical switch is a pressure switch.