Sheet material dispenser with perforation sensor and method

• US 20020117578A1
• Filed: 02/27/2001
• Published: 08/29/2002
• Est. Priority Date: 02/27/2001
• Status: Active Grant

• Current Assignee: Georgia-Pacific Consumer Products LP (KOCH Industries Incorporated)
• Original Assignee: Georgia-Pacific Corporation
• Inventors: Denen, Dennis J., Broehl, Joshua M., Knittle, John J.
• Granted Patent: US 6,766,977 B2
• Time in Patent Office: Days
• US Class Current: 242/563
• CPC Class Codes: A47K 10/3612 with drive and pinch rollers
• CPC Class Codes: A47K 10/3625 with electronic control means
• CPC Class Codes: A47K 2010/3675 Braking devices
• CPC Class Codes: B65H 2511/512 Marks, e.g. invisible to the human eye; Patterns
• CPC Class Codes: B65H 2553/412 in barrier arrangements, i.e. emitter facing a receptor element
• CPC Class Codes: B65H 35/10 from or with devices for breaking partially-cut or perforated webs, e.g. bursters
• CPC Class Codes: B65H 43/00 Use of control, checking, or safety devices, e.g. automatic devices comprising an element for sensing a variable
• CPC Class Codes: Y10T 225/205 With feed-out of predetermined length from work supply
• CPC Class Codes: Y10T 225/211 Manually operated feed-out mechanism

Abstract

A dispenser for dispensing sheet material including a plurality of spaced perforations may include a housing defining an interior for accommodating a source of the sheet material, and an outlet through which the sheet material may be dispensed. The device may also include a perforation sensor configured to sense perforations in the sheet material, disposed in the interior of the housing. The perforation sensor may include at least one light receptor, and at least a portion of the perforation sensor may be positioned in the housing to contact sheet material traveling from the source to the outlet, thereby spreading perforations in the sheet material.

Claims

1. A dispenser for dispensing sheet material including a plurality of spaced perforations, said dispenser comprising:

a housing defining an interior for accommodating a source of the sheet material, and an outlet through which the sheet material is dispensed; and

a perforation sensor configured to sense perforations in the sheet material, the perforation sensor being disposed in the interior of the housing, the perforation sensor including at least one light receptor, at least a portion of said perforation sensor being positioned in the housing to contact sheet material traveling from the source to the outlet and thereby spread perforations in the sheet material.

2. The dispenser according to claim 1, wherein the portion of the perforation sensor is a light emitter configured to emit light capable of being detected by the light receptor, the light emitter and the light receptor being spaced apart from one another such that the sheet material can be positioned therebetween to pass the light from the emitter to the receptor via the perforations, the spreading of the perforations increasing the amount of light passing through the perforations.

3. The dispenser according to claim 1, wherein the sheet material is dispensed in a first direction, the perforation sensor being located in the housing such that the portion of the perforation sensor contacts the approximate middle of the sheet material in a second direction perpendicular to said first direction.

4. The dispenser according to claim 1, further comprising at least one rotatable roller in the housing, at least a portion of the sheet material being in contact with the roller when the sheet material travels from the source to the outlet.

5. The dispenser according to claim 4, wherein the roller includes at least two spaced sections and wherein the portion of the perforation sensor is positioned between the roller sections to contact sheet material on the rollers.

6. The dispenser according to claim 4, further comprising a brake configured to brake rotational movement of the roller and a controller for controlling the brake, the controller being in electrical communication with the perforation sensor.

7. The dispenser according to claim 6, wherein said brake includes a detent member coupled to the roller, and a solenoid mounted to the housing, said detent member having a plurality of detents provided thereon, said solenoid having a plunger configured to selectively engage a respective one of said detents.

8. A dispenser for dispensing sheet material including a plurality of spaced perforations, said dispenser comprising:

a housing defining an interior for accommodating a source of the sheet material, and an outlet through which the sheet material is dispensed; and

a perforation sensor configured to sense perforations in the sheet material, the perforation sensor being disposed in the interior of the housing, the perforation sensor including a pair of light receptors, said pair of light receptors being aligned in substantially the direction of sheet material travel from the source to the outlet such that one of the receptors receives light passing through one of the perforations before the other of the receptors.

9. The dispenser according to claim 8, wherein the perforation sensor further includes a differential trans-impedance amplifier for detecting light incident upon at least one of the light receptors.

10. The dispenser according to claim 9, wherein the differential trans-impedance amplifier is configured as a balanced bridge for amplifying the difference in intensity of light detected by the two light receptors.

11. The dispenser according to claim 10, wherein the perforation sensor further comprises a light emitter configured to emit light capable of being detected by the light receptors, the light emitter being arranged with respect to the receptors such that light falls substantially equally on both receptors when sheet material is not positioned between the light emitter and the pair of light receptors.

12. The dispenser according to claim 9, wherein the differential trans-impedance amplifier comprises:

a first operational amplifier having an inverting input node, a non-inverting input node, and an output node;

a second operational amplifier having an inverting input node, a non-inverting input node, and an output node;

a feedback resistor having a first end and a second end, wherein the first end is electrically coupled to the inverting input node of the first operational amplifier;

a scaling resistor having a first end and a second end, wherein the first end of the scaling resistor is electrically coupled to the second end of the feedback resistor and the second end of the scaling resistor is electrically coupled to the inverting input node of the second operational amplifier; and

a gain resistor having a first end and a second end, wherein the first end of the gain resistor is electrically coupled to the inverting input node of the second operational amplifier and the second end of the gain resistor is electrically coupled to the output node of the second operational amplifier.

13. The dispenser according to claim 8, wherein the perforation sensor includes a light emitter spaced from the pair of receptors such that the sheet material passes between the light emitter and the pair of light receptors during travel of the sheet material to the outlet.

14. The dispenser according to claim 8, wherein the sheet material includes lines of the perforations defining individual sheets, and wherein the receptors are arranged such that the receptors are aligned along an axis substantially perpendicular to lines of perforations on the sheet material traveling adjacent to the receptors.

15. The dispenser according to claim 8, further comprising at least one rotatable roller in the housing, at least a portion of the sheet material being in contact with the roller when the sheet material travels from the source to the outlet.

16. The dispenser according to claim 15, wherein the roller includes at least two spaced sections and wherein a portion of the sensor is positioned between the roller sections to contact sheet material on the rollers.

17. The dispenser according to claim 15, further comprising a brake configured to brake rotational movement of the roller and a controller for controlling the brake, the controller being in electrical communication with the perforation sensor.

18. The dispenser according to claim 17, wherein said brake includes a detent member coupled to the roller, and a solenoid mounted to the housing, said detent member having a plurality of detents provided thereon, said solenoid having a plunger configured to selectively engage a respective one of said detents when the perforation sensor detects a perforation.

19. The dispenser according to claim 8, further comprising a controller, said controller comparing the amount of light detected by each light receptor.

20. A dispenser for dispensing sheet material including a plurality of perforations, said dispenser comprising:

a housing defining an interior for accommodating a source of the sheet material, and an outlet through which the sheet material is dispensed; and

a perforation sensor disposed in the interior of the housing, the perforation sensor being configured to sense perforations in the sheet material and including at least one light receptor and a light emitter, the light receptor and the light emitter being spaced apart from one another such that the sheet material travels therebetween to pass light from the emitter to the receptor via the perforations.

21. The dispenser according to claim 20, wherein the sheet material is dispensed in a first direction, the perforation sensor being located in the housing such that the perforation sensor is adjacent to the approximate middle of the sheet material in a second direction perpendicular to said first direction.

22. The dispenser according to claim 20, further comprising a first rotatable roller in the housing, said first roller including at least two spaced roller sections, at least a portion of the sheet material being in contact with the first roller when the sheet material travels from the source to the outlet, one of said light receptor and said light emitter being positioned between said roller sections.

23. The dispenser according to claim 22, further comprising a second rotatable roller in the housing, the first and second rollers defining a nip for the sheet material.

24. The dispenser according to claim 20, further comprising a controller in said housing, said controller selectively activating the perforation sensor.

25. The dispenser according to claim 24, further comprising at least one rotatable roller in the housing, at least a portion of the sheet material being in contact with the roller when the sheet material travels from the source to the outlet, wherein the dispenser further comprises a rotation monitor configured to monitor rotation of the roller, the controller being in electrical communication with the rotation monitor and activating the perforation sensor when the monitor detects a first predetermined amount of rotation of the roller.

26. The dispenser according to claim 25, further comprising a brake configured to brake rotational movement of the roller, the controller selectively activating the brake.

27. The dispenser according to claim 26, wherein the controller is configured to activate the brake when the perforation sensor senses a perforation in the sheet material.

28. The dispenser according to claim 26, wherein the controller is configured to activate the brake when the rotation monitor detects a second predetermined amount of rotation of the roller.

30. The dispenser according to claim 29, wherein the sheet material is dispensed in a first direction, the perforation sensor being located in the housing such that the portion of the perforation sensor contacts the approximate middle of the sheet material in a second direction perpendicular to said first direction.

31. The dispenser according to claim 29, further comprising a brake configured to brake rotational movement of the roller and a controller for controlling the brake, the controller being in electrical communication with the perforation sensor.

32. The dispenser according to claim 31, wherein said brake includes a detent member coupled to the roller, and a solenoid mounted to the housing, said detent member having a plurality of detents provided thereon, said solenoid having a plunger configured to selectively engage a respective one of said detents.

33. The dispenser according to claim 29, further comprising a controller in said housing, said perforation sensor including a pair of light receptors, said controller comparing the amount of light detected by each light receptor.

34. The dispenser according to claim 29, further comprising a controller in said housing, said controller selectively activating the perforation sensor.

35. The dispenser according to claim 29, wherein the perforation sensor includes at least one light receptor and a light emitter, the light receptor and light emitter being spaced apart from one another to pass light from the emitter to the receptor via the perforations.

36. The dispenser according to claim 29, further comprising a second rotatable roller in the housing, the first and second rollers defining a nip for the sheet material.

37. The dispenser according to claim 33, further comprising a rotation monitor configured to monitor the rotation of the roller, the controller being in electrical communication with the rotation monitor and activating the perforation sensor when the rotation monitor detects a first predetermined amount of rotation of the roller.

38. The dispenser according to claim 37, further comprising a brake configured to brake rotational movement of the roller, the controller selectively activating the brake.

39. The dispenser according to claim 38, wherein the controller is configured to activate the brake when the perforation sensor senses a perforation in the sheet material.

40. The dispenser according to claim 38, wherein the controller is configured to activate the brake when the rotation monitor detects a second predetermined amount of rotation of the roller.

29. A dispenser for dispensing sheet material including a plurality of spaced perforations, said dispenser comprising:

a housing defining an interior for accommodating a source of the sheet material, and an outlet through which the sheet material is dispensed;

at least one rotatable roller in the housing, said roller including at least two spaced roller sections, a portion of the sheet material being in contact with the roller when the sheet material travels from the source to the outlet; and

a perforation sensor disposed in the interior of the housing, the perforation sensor being configured to sense perforations in the sheet material, at least a portion of the perforation dispenser being positioned between the roller sections.

41. A dispenser for dispensing sheet material including a plurality of spaced perforations, said dispenser comprising:

a housing defining an interior for accommodating a source of the sheet material, and an outlet through which the sheet material is dispensed;

at least one rotatable roller in the housing, at least a portion of the sheet material being in contact with the first roller when the sheet material travels from the source to the outlet; and

a rotation monitor configured to monitor the amount of rotation of the roller to thereby determine the amount of sheet material traveling downstream from the roller.

42. The dispenser according to claim 41, further comprising a brake configured to brake rotational movement of the roller, and a controller configured to selectively activate the brake.

43. The dispenser according to claim 42, wherein the controller is configured to activate the brake when the rotation monitor detects a predetermined amount of rotation of the roller.

44. The dispenser according to claim 42, further comprising a perforation sensor configured to sense perforations in the sheet material, wherein the controller activates the brake when the perforation sensor senses a perforation.

45. The dispenser according to claim 41, further comprising a perforation sensor configured to sense perforations in the sheet material and a controller configured to selectively activate the perforation sensor when the rotation monitor detects a predetermined amount of rotation of the roller.

47. The method according to claim 46, further comprising monitoring the amount of rotation of the roller and activating the perforation sensor when the roller rotates a first predetermined amount.

48. The method according to claim 47, wherein the activating of the brake occurs when the perforation sensor detects a perforation and the roller rotates a second predetermined amount.

49. The method according to claim 46, wherein the brake includes a detent member and a solenoid having an arm configured to selectively engage the detent member when the solenoid is activated, wherein the activating of the brake includes activating the solenoid.

46. A method of dispensing sheet material, comprising:

providing a dispenser containing a source of sheet material including a plurality of spaced perforations, the dispenser comprising a perforation sensor including at least one light receptor and a light emitter, at least one rotatable roller, a brake configured to selectively brake rotation of the roller, and an outlet for dispensing sheet material;

passing sheet material from the source to the outlet, wherein the sheet material contacts the roller and the roller rotates, and wherein the sheet material passes between the light receptor and the light emitter;

detecting a perforation in the sheet material by sensing an increased amount of light reaching said light receptor from said light emitter; and

activating the brake to cause tension in the sheet material when an end portion of the sheet material is pulled.

50. A method of dispensing sheet material, comprising:

providing a dispenser for containing a source of sheet material including a plurality of spaced perforations, the dispenser comprising at least one rotatable roller, a rotation monitor configured to monitor the amount of rotation of the roller to thereby determine the amount of sheet material traveling downstream from the roller, a brake configured to selectively brake rotation of the roller, and an outlet for dispensing sheet material;

passing sheet material from the source to the outlet, wherein the sheet material contacts the roller and the roller rotates;

monitoring the amount of rotation of the roller to thereby determine the amount of sheet material dispensed; and

activating the brake when a predetermined amount of sheet material is dispensed, the braking of the roller causing tension in the sheet material when an end portion of the sheet material is pulled.

51. The method according to claim 50, wherein the dispenser further comprises a perforation sensor including at least one light receptor and a light emitter, the method further comprising detecting an initial rotation of the roller and activating the perforation sensor when the roller rotates a first predetermined amount of rotation, the activating of the brake occurring when at least one of the perforation sensor detects a perforation and the roller rotates a second predetermined amount.

52. A method of dispensing sheet material from a dispenser containing a source of sheet material having a plurality of spaced perforations, the dispenser comprising at least one rotatable roller, a rotation monitor configured to monitor the amount of rotation of the roller to thereby determine the amount of sheet material traveling downstream from the roller, a perforation sensor for sensing perforations in the sheet material, and an outlet for dispensing sheet material, the method comprising:

detecting the amount of rotation of the roller;

sensing a perforation in the sheet material; and

in response to detection of said perforation, stopping the advancing of the sheet material when the roller rotates a first predetermined amount.

53. The method of claim 52, further including:

detecting an initial rotation of the roller.

54. The method of claim 53, further including:

activating the perforation sensor after a second predetermined amount of rotation of the roller.

55. The method of claim 54, further including:

in response to no perforation being detected when the roller rotates a third predetermined amount, stopping the advancing of the sheet material.

56. The method of claim 55, wherein the dispenser includes a brake configured to selectively brake rotation of the roller, and wherein the stopping of sheet material advancing includes activating the brake.

58. A dispenser according to claim 57, further comprising a brake configured to brake rotational movement of the roller and a controller for controlling the brake, the controller being in electrical communication with the perforation sensor and rotation monitor.

59. A dispenser according to claim 58, wherein said controller receives a rotation signal from the rotation monitor indicating the amount of rotation of the roller, said controller activating said perforation sensor when the roller rotates a first predetermined amount.

60. A dispenser according to claim 59, wherein the controller activates the brake when the perforation sensor senses a perforation and the roller rotates a second predetermined amount.

57. A dispenser for dispensing sheet material including a plurality of spaced perforations, said dispenser comprising:

a housing defining an interior for accommodating a source of the sheet material, and an outlet through which the sheet material is dispensed;

at least one rotatable roller in the housing, at least a portion of the sheet material being in contact with the roller when the sheet material travels from the source to the outlet;

a perforation sensor disposed in the interior of the housing, the perforation sensor being configured to sense perforations in the sheet material; and

a rotation monitor configured to monitor the amount of rotation of the roller to thereby determine the amount of sheet material traveling downstream from the roller.

61. A sensor for detecting perforations in sheet material, said sensor comprising:

a pair of light receptors, said pair of light receptors being aligned substantially parallel to each other, such that one of the receptors receives light passing through one of the perforations before the other of the receptors; and

a differential trans-impedance amplifier for detecting light incident upon the two light receptors.

62. The sensor according to claim 61, wherein the differential trans-impedance amplifier is configured as a balanced bridge for amplifying the difference in intensity of light detected by the pair of light receptors.

63. The sensor according to claim 62, wherein the differential trans-impedance amplifier comprises:

a first operational amplifier having an inverting input node, a non-inverting input node, and an output node;

a second operational amplifier having an inverting input node, a non-inverting input node, and an output node;

a feedback resistor having a first end and a second end, wherein the first end is electrically coupled to the inverting input node of the first operational amplifier;

a scaling resistor having a first end and a second end, wherein the first end of the scaling resistor is electrically coupled to the second end of the feedback resistor and the second end of the scaling resistor is electrically coupled to the inverting input node of the second operational amplifier; and

a gain resistor having a first end and a second end, wherein the first end of the gain resistor is electrically coupled to the inverting input node of the second operational amplifier and the second end of the gain resistor is electrically coupled to the output node of the second operational amplifier.

64. A dispenser for dispensing sheet material including a plurality of spaced perforations, said dispenser comprising:

a housing defining an interior for accommodating a source of the sheet material, and an outlet through which the sheet material is dispensed; and

the perforation sensor according to claim 61.

65. The dispenser according to claim 64, wherein the perforation sensor further includes a light emitter configured to emit light capable of being detected by the light receptors.

66. The dispenser according to claim 65, wherein the light emitter and the light receptor are spaced apart from one another such that the sheet material can be positioned therebetween to pass the light from the emitter to the receptor via the perforations.

67. The dispenser according to claim 64, further comprising at least one rotatable roller in the housing, at least a portion of the sheet material being in contact with the roller when the sheet material travels from the source to the outlet.

68. The dispenser according to claim 67, wherein the roller includes at least two spaced sections and wherein a portion of the perforation sensor is positioned between the roller sections to contact sheet material on the rollers.

69. The dispenser according to claim 64, further comprising a brake configured to brake rotational movement of the roller and a controller for controlling the brake, the controller being in electrical communication with the perforation sensor.

70. The dispenser according to claim 69, wherein said brake includes a detent member coupled to the roller, and a solenoid mounted to the housing, said detent member having a plurality of detents provided thereon, said solenoid having a plunger configured to selectively engage a respective one of said detents.