US3614419A - Multiple sheet detection system - Google Patents

Multiple sheet detection system Download PDF

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Publication number
US3614419A
US3614419A US25766A US3614419DA US3614419A US 3614419 A US3614419 A US 3614419A US 25766 A US25766 A US 25766A US 3614419D A US3614419D A US 3614419DA US 3614419 A US3614419 A US 3614419A
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US
United States
Prior art keywords
sheet
circuit means
path
sheets
circuit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US25766A
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English (en)
Inventor
John W Daughton
James M Donohue
Gary L Schluntz
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Xerox Corp
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Xerox Corp
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/70—Detecting malfunctions relating to paper handling, e.g. jams
    • G03G15/703—Detecting multiple sheets
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H7/00—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles
    • B65H7/02—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles by feelers or detectors
    • B65H7/06—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles by feelers or detectors responsive to presence of faulty articles or incorrect separation or feed
    • B65H7/12—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles by feelers or detectors responsive to presence of faulty articles or incorrect separation or feed responsive to double feed or separation
    • B65H7/125—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles by feelers or detectors responsive to presence of faulty articles or incorrect separation or feed responsive to double feed or separation sensing the double feed or separation without contacting the articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2553/00—Sensing or detecting means
    • B65H2553/40—Sensing or detecting means using optical, e.g. photographic, elements
    • B65H2553/41—Photoelectric detectors

Definitions

  • An electronic circuit is coupled to the photosensor which experiences a change in resistance depending upon the transmittance of a sheet or sheets in the sheet path and provides an output signal when there is a multiple sheet condition.
  • the electronic circuit includes a motor-driven potentiometer which is utilized as a memory for a previously fed sheet in a feedback circuit for comparison with a signal representative of the next sheet.
  • the circuit may be calibrated for varying circuit parameters to accommodate different sheet weights and types.
  • PATENTEDHBT 19 Ian SHEET 1 OF 4 INVENTORS. JOHN W. DAUGHTON 7 JAMES M. DONOHUE BY GARY L. SCHLUNTZ ATTORNEY "PAIENTEnncI 19m.
  • This invention relates to a multiple sheet detection system to detect the presence of superposed sheets advanced along a sheet path and to indicate to a machine control that a multiple sheet feed condition has occurred.
  • lt is another object of the invention to enable detection of multiple sheets being fed past a detection station at very high rates.
  • the detection system of the invention is a
  • FlG. 1 illustrates schematically a xerographic recording apparatus incorporating a multiple sheet detection system constructed in accordance with the present invention
  • FIG. 2 is an enlarged view of a sheet feed section of the apparatus illustrating lamp and photosensor assemblies of the present invention and their relationship to the sheet feed path;
  • FIG. 3 is a circuit diagram of the multiple sheet detection system
  • FIG. 4 is a diagram illustrating signal voltage variations indicative of single and multiple sheet feed conditions.
  • FIG. 1 there are shown various components of a xerographic recording machine which produces enlarged copies of microfilm aperture cards on cut sheets of different sizes and weights at high rates and which utilizes a multiple sheet detection system according to the present invention.
  • a light image of an original to be reproduced is projected onto the sensitized surface of a xerographic plate to form an electrostatic latent image thereon.
  • the latent image is developed with an oppositely charged developing material to form a powder image corresponding to the latent image on the plate surface.
  • the powder image is then electrostatically transferred to a support surface such as paper to which it ispermanently affixed.
  • aperture cards are placed in a card feed section 16 from which each card is fed in seriatim in a path transverse to the optical path to scan a film frame on the card in timed relation to the movement of a xerographic plate which is in the form of a drum 20.
  • Xerographic drum 20 comprises a layer of photoconductive material on a conductive backing and is mounted in suitable bearings in a machine frame and driven by a suitable drive. The drum passes first a charging station A at which a uniform electrostatic charge is deposited by a corona-generating device 21.
  • the drum is exposed to a light image to discharge the photoconductive layer in the areas struck by light whereby there remains on the drum at latent electrostatic image corresponding to the film frame on the aperture card being scanned.
  • the electrostatic latent image passes through a development station C at which a developing material including toner particles having electrostatic charge opposite to that of the electrostatic latent image are cascaded across the drum surface whereby the toner particles adhere to the latent image to form a powdered image.
  • additional toner particles are supplied to the developing material in proportion to the amount of toner deposited on the drum.
  • an image transfer station D Positioned adjacent to the development stating C is an image transfer station D at which the powder images are electrostatically transferred from the drum surface to sheet material supplied from a sheet feed station past a sheet detection station in a manner as will be explained more fully hereinafter.
  • a sheet transport apparatus serves to transport the sheet material received from a sheet feed section 27 toward a transfer station D where a corona transfer device 29 similar to the corona-charging device 21 is located to effect the electrostatic transfer of the developed image onto the sheet material.
  • the powder image is permanently affixed to the sheet material by a heat fuser apparatus 31 and the sheet material conveyed onto a vertical transport 33 for delivery to a copy tray 35.
  • a drum-cleaning station E comprises a corona discharge device 37 and brush 39 to remove residual toner particles remaining on the drum surface after image transfer, and a light source 40 to complete discharge of any residual electrostatic charge remaining on the surface whereby the drum may be ready for another cycle to pass through the processing stations as just described.
  • FIG. 2 there is shown a sheet detection station located at the exit side of sheet feed section 27 which feeds sheets of different sizes and/or types as selected from a conveniently located control panel. Sheets are fed desirably one at a time toward guide members 45 which converge and terminate at the exit of the sheet feed sections where the multiple sheet detection station is positioned.
  • the sheet feed section is modular and is of the type which can be easily pulled away from the rest of the xerographic recording machine as described more fully in the previously mentioned copending application if desired.
  • Lamp assembly 51 situated below the sheet feed path and a photosensor assembly 53 located just above the sheet path which assemblies are mounted on the frame of the sheet feed section.
  • Lamp assembly 51 includes a lamp DS! or any suitable source of illumination in a housing 57 formed with an aperture 59 such that illumination from the lamp is directed across the sheet path to be sensed on a photosensitive element Vl through the aperture 63 located in a housing 65.
  • Photosensitive element V1 may be any suitable light-sensitive device.
  • the photosensitive element may comprise a photocell, photovoltaic cell, photoconductor, phototransistor, photodiode, light activated SCR, etc.
  • Lamp D81 is adjustable relative to the lamp housing as by screws 67 received in the housing against the action of springs 68. it will be appreciated that the overall configuration of the lamp and its aperture and the photosensitive element, and its aperture is such that any variation in sensitivity due to differences in the sheet path is minimized.
  • illumination from the lamp D81 is interrupted which causes an increase in the resistance of the photosensitive element which is coupled to an electronic circuit as will be described.
  • Thephotosensitive element resistance level normally generated by advancing single sheets is such as to be repeatable if the light transmission of the sheet is the same or nearly the same.
  • the drop in light transmission causes the resistance of the photosensitive element to increase significantly above the resistance generated by a single sheet.
  • the electronic circuit coupled to the photosensitive element utilizes this resistance change to provide an output signal to a machine control to indicate the presence of multiple sheets.
  • the circuit has a regulated well-filtered power supply which is made up of transformer T1, bridge rectifier CR1, resistors R1, R3 and R4, capacitors Cl and C2 and zener diodes CR2 and CR3. It has been found that output voltages from such a power supply of about plus and minus 12 volts performs well for purposes of the present invention.
  • Transformer T1 also provides a supply voltage for lamp 081.
  • a resistor R20 is used to provide an unfiltered power source for relays which are energized in a manner and a purpose to be described hereinafter.
  • Resistors R2 and R6 and atrim pot R5 serve to make up a reference voltage divider.
  • an offset voltage Y is desirable which ranges from about 0.5 volts to about 2 volts and preferably about 1.2 volts (FIG. 4).
  • the photosensitive element V1 which in this case is a photocell, a resistor R19 and a multiturn pot R37 serve as the active transmittance-sensitive input to the circuit.
  • the resistance of the photocell When no sheet is present in the feed path at the detection station, the resistance of the photocell is very low or in the order of about 1 K ohms. For this condition, the voltage at point E will be approximately ll volts. However, when a single sheet is present at the detection station, the photocell resistance will be greatly increased and the voltage at point E decreases to about 6 volts. it will be appreciated that the exact voltage level will depend upon such things as the transmittance of each particular sheet of material and that this will vary with the density of any given material, as by about one-half to about 1 volt.
  • point E is connected to the negative input of a differential amplifier 03 and also to the positive input of a differential amplifier Q7.
  • point C is connected to a positive input of a differential amplifier Q3 and to the negative input of a differential amplifier Q7.
  • the differential amplifiers Q3 and 07 serve to make upa null detector.
  • point B of the circuit is positive with respect to point C
  • 07 will be turned on and Q3 will be turned off.
  • point C of the circuit is positive with respect to point E
  • 03 will be turned on and 07 will be turned off.
  • relays K2 and K3 are driven by differential amplifiers Q2 and Q7 and driver transistors 06 and Q8, respectively. Relays K2 and K3, in turn, operate bidirectional motor B20 which drives multiturn potentiometer R37.
  • null detector 03 and Q7 and bidirectional motor B20 and potentiometer R37 serve as a feedback circuit which is responsive to the light transmission of each sheet being fed past the detection station.
  • the potentiometer R37 will be driven by bidirectional motor B20 in a direction toward the null.
  • bidirectional motor B20 is energized when one or more sheets are present at the detection station.
  • a differential amplifier Q2 serves as a switch which turns on transistor 05 only when there is sheet material at the detection station.
  • Resistors R7 and R21 make up a voltage divider which sets the voltage at point M to about 8 volts.
  • Point M is connected to the positive input of Q2 and point B is connected to the negative input.
  • Q2 is turned on only when point M is positive with respect to point E of the circuit and can occur only when there is sheet material at the detection station.
  • Q5 provides a path for transistors Q6 and Q8 and relays K1 and K2.
  • Q5 which is driven by 02 must be on before Kl or K2 can be actuated.
  • bidirectional motor B20 can drive potentiometer R37 only when sheet material is present at the detection station.
  • point E is driven negative with respect to point D of the circuit.
  • differential amplifier O1 is turned on.
  • the negative input of Q] is connected to point E. Due to the feedback loop mentioned above, the voltage at point E is approximately equal to the voltage at point C. It will be noted that the voltage at point D which is connected to the positive input of Qi is about 1.2 volts negative with respect to point C. By this arrangement, the voltage at point D is about l.2 volts negative with respect to point E. It will now be appreciated that the voltage at point E must be driven negative with respect to point D in order for transistor 01 to be turned on. Furthermore, point E is driven negative with respect to point D only when a multiple sheet condition exists.
  • relay Kl which is driven by Q9 provides an output to machine control only when 01 is turned on or when multiple sheets are fed past the detection station.
  • a visual indication of the multiple sheets is provided by a lamp DS2 in the circuit and conveniently located on the machine.
  • motor B be prevented from driving potentiometer R37 when a multiple sheet condition occurs.
  • 04 will be turned on by 01; thereby preventing Q5 from turning on, thereby precluding motor B20 from driving potentiometer R37.
  • the motor B20 cannot drive when there either is no sheet material at the detection station or when multiple sheets are detected.
  • the system is adapted for calibration to meet such varying conditions.
  • a calibration switch S38 is provided to be manually actuated during the time that a single sheet of the material of the type to be fed is introduced at the detection station. Switch S38 is held actuated until such time as the motor B20 turns off which is indicated when lamp D82 is deenergized. Wen this occurs, calibration is complete since the feedback circuit previously described is adapted to store the transmittance information derived during calibration of a single sheet.
  • the invention described above enables multiple sheets to be detected in a rapid and simple manner with a high reliability. Moreover, a great latitude of sheet weights and types can be accommodated. It will be appreciated that the sheet detection system of the invention is highly desirable for present-day copier/duplicator machines.
  • a multiple sheet detection system comprising photosensitive means positioned on one side of a sheet path at a sheet detection station,
  • illumination means located on the opposite side of the sheet path for directing illumination towards said photosensitive means
  • circuit means coupled to said photosensitive means operative to determine the presence of multiple sheets includmg first circuit means for generating discrete electrical signals representative of the transmittance of sheet material advanced along the sheet path, second circuit means for storing a previous signal supplied from said first circuit means, and third circuit means for comparing the stored signal with a succeeding signal generated from said first circuit means to determine the presence of multiple sheets and generating an output signal when amultiple sheet condition occurs.
  • a system according to claim 1 including means to prevent said second circuit means from storing signals when sheet material is not present at the sheet detection station.
  • a system according to claim 2 wherein said second circuit means comprises a potentiometer operatively connected to bidirectional motor.
  • a system according to claim 3 including switching means coupled to said second circuit means to enable the setting of said potentiometer to be varied to establish a reference level for different sheet weights and types.
  • an improved detection apparatus for detecting multiple sheets at a sheet detection station comprising means for feeding sheet material along a sheet path past copy-processing stations,
  • photosensitive means positioned on one side of the sheet path at the sheet detection station
  • illumination means located on the opposite side of the sheet path for directing illumination towards said photosensitive means
  • circuit means coupled to said photosensitive means to determine the presence of multiple sheets at said detection station and indicate such condition to machine control
  • circuit means including first circuit means for generating discrete electrical signals representative of the transmittance of sheet material advanced along the sheet path,
  • second circuit means for storing signals supplied from said first circuit means, and third circuit means for comparing each stored signal with a succeeding signal generated from said first circuit means to determine the presence of multiple sheets and generating an output signal to machine control when a multiple sheet condition occurs.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Controlling Sheets Or Webs (AREA)
US25766A 1970-04-06 1970-04-06 Multiple sheet detection system Expired - Lifetime US3614419A (en)

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US2576670A 1970-04-06 1970-04-06

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US3614419A true US3614419A (en) 1971-10-19

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US (1) US3614419A (enExample)
BE (1) BE765366A (enExample)
CA (1) CA930052A (enExample)
DE (1) DE2116803A1 (enExample)
FR (1) FR2089733A5 (enExample)
GB (1) GB1342656A (enExample)
NL (1) NL7104413A (enExample)

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3873843A (en) * 1973-11-29 1975-03-25 Mohawk Data Sciences Corp Document detection apparatus
US4011447A (en) * 1976-02-09 1977-03-08 Henderson George R System for detecting the edges of a moving object employing a photocell and an amplifier in the saturation mode
US4072854A (en) * 1975-07-30 1978-02-07 Glory Kogyo Kabushiki Kaisha Sheet counting apparatus
US4124968A (en) * 1977-07-08 1978-11-14 Opex Corporation Content activated envelope extraction
US4237378A (en) * 1977-12-28 1980-12-02 Brandt-Pra, Inc. Photoelectric apparatus for document counting and overlap detection
US4286149A (en) * 1979-08-09 1981-08-25 Ncr Canada Ltd - Ncr Canada Ltee Apparatus and method for detection of overlapping objects
US4353197A (en) * 1977-07-08 1982-10-12 Opex Corporation Content activated envelope extraction
US4398711A (en) * 1979-12-31 1983-08-16 Ncr Corporation Currency dispenser monitor
EP0087487A1 (en) * 1982-03-01 1983-09-07 Christian P. Bourg Sheet collator
EP0149699A1 (en) * 1984-01-24 1985-07-31 Komori Printing Machinery Co., Ltd. Double sheet detection method and apparatus of sheet-fed rotary press
US4593533A (en) * 1974-12-05 1986-06-10 Alsenz Richard H Method and apparatus for detecting and controlling the formation of ice or frost
US4608704A (en) * 1982-11-10 1986-08-26 Brandt, Incorporated Method and apparatus for counting sheets which may be fed in skewed and/or overlapping fashion
US4642456A (en) * 1985-03-21 1987-02-10 Komori Printing Double sheet detection method and apparatus of sheet-fed rotary press
US4652742A (en) * 1982-08-17 1987-03-24 Agfa-Gevaert Ag Arrangement for and method of determining two or more superimposed film sheets
US4703172A (en) * 1982-11-10 1987-10-27 Brandt, Incorporated Method and apparatus for counting sheets which may be fed in skewed and/or overlapping fashion
US4707599A (en) * 1982-11-10 1987-11-17 Brandt, Incorporated Method and apparatus for counting sheets which may be fed in skewed and/or overlapping fashion
US4709914A (en) * 1985-02-07 1987-12-01 Brandt, Inc. Electronic controller for dispensers and the like
US4798646A (en) * 1985-11-12 1989-01-17 Somar Corporation Film peeling apparatus having film end detector
US4815669A (en) * 1986-09-08 1989-03-28 Sharp Kabushiki Kaisha Shredder
US5384468A (en) * 1993-07-22 1995-01-24 Ncr Corporation Apparatus and method for indicating the thickness of record media by forcing a spaced roller into engagement with a pulse generator
US5614710A (en) * 1995-06-07 1997-03-25 Electrocom Automation L.P. Dichotomous scan system for detection of overlapped objects
US5659396A (en) * 1995-06-07 1997-08-19 Electrocom Automation L.P. Dichotomous scan system for detection of edges of objects and overlapped objects having relatively uniform surfaces
EP0921083A3 (en) * 1997-11-05 1999-08-04 Ncr International Inc. System for detecting superposed sheets
US6241244B1 (en) * 1997-11-28 2001-06-05 Diebold, Incorporated Document sensor for currency recycling automated banking machine
US6463824B1 (en) * 2000-02-29 2002-10-15 S-B Power Tool Company Right angle attachment for power hand tool
US20070251192A1 (en) * 2006-04-27 2007-11-01 Pitney Bowes Incorporated Method of sensing pack insertion at crease line of envelope

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD135817B1 (de) * 1978-04-17 1981-09-30 Albrecht Johne Kapazitive Kontroll- und Auswerteeinrichtung
SE430547B (sv) * 1979-07-26 1983-11-21 Lundblad Leif Anordning for utmatning av dokument
GB2194040A (en) * 1986-07-23 1988-02-24 Ratby Eng Co Ltd Paper feed control apparatus
CN112317558B (zh) * 2020-09-04 2023-01-17 中国第一汽车股份有限公司 一种冲压自动线板料张数快速电学检测系统及方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3026419A (en) * 1959-05-11 1962-03-20 Ibm Overlap detector

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3026419A (en) * 1959-05-11 1962-03-20 Ibm Overlap detector

Cited By (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3873843A (en) * 1973-11-29 1975-03-25 Mohawk Data Sciences Corp Document detection apparatus
US4593533A (en) * 1974-12-05 1986-06-10 Alsenz Richard H Method and apparatus for detecting and controlling the formation of ice or frost
US4072854A (en) * 1975-07-30 1978-02-07 Glory Kogyo Kabushiki Kaisha Sheet counting apparatus
US4011447A (en) * 1976-02-09 1977-03-08 Henderson George R System for detecting the edges of a moving object employing a photocell and an amplifier in the saturation mode
US4124968A (en) * 1977-07-08 1978-11-14 Opex Corporation Content activated envelope extraction
US4353197A (en) * 1977-07-08 1982-10-12 Opex Corporation Content activated envelope extraction
US4237378A (en) * 1977-12-28 1980-12-02 Brandt-Pra, Inc. Photoelectric apparatus for document counting and overlap detection
US4286149A (en) * 1979-08-09 1981-08-25 Ncr Canada Ltd - Ncr Canada Ltee Apparatus and method for detection of overlapping objects
US4398711A (en) * 1979-12-31 1983-08-16 Ncr Corporation Currency dispenser monitor
EP0087487A1 (en) * 1982-03-01 1983-09-07 Christian P. Bourg Sheet collator
US4652742A (en) * 1982-08-17 1987-03-24 Agfa-Gevaert Ag Arrangement for and method of determining two or more superimposed film sheets
US4608704A (en) * 1982-11-10 1986-08-26 Brandt, Incorporated Method and apparatus for counting sheets which may be fed in skewed and/or overlapping fashion
US4703172A (en) * 1982-11-10 1987-10-27 Brandt, Incorporated Method and apparatus for counting sheets which may be fed in skewed and/or overlapping fashion
US4707599A (en) * 1982-11-10 1987-11-17 Brandt, Incorporated Method and apparatus for counting sheets which may be fed in skewed and/or overlapping fashion
US4642457A (en) * 1984-01-24 1987-02-10 Komori Printing Machinery Co., Ltd. Double sheet detection method and apparatus of sheet-fed rotary press
EP0149699A1 (en) * 1984-01-24 1985-07-31 Komori Printing Machinery Co., Ltd. Double sheet detection method and apparatus of sheet-fed rotary press
US4709914A (en) * 1985-02-07 1987-12-01 Brandt, Inc. Electronic controller for dispensers and the like
US4642456A (en) * 1985-03-21 1987-02-10 Komori Printing Double sheet detection method and apparatus of sheet-fed rotary press
US4798646A (en) * 1985-11-12 1989-01-17 Somar Corporation Film peeling apparatus having film end detector
US4815669A (en) * 1986-09-08 1989-03-28 Sharp Kabushiki Kaisha Shredder
US5384468A (en) * 1993-07-22 1995-01-24 Ncr Corporation Apparatus and method for indicating the thickness of record media by forcing a spaced roller into engagement with a pulse generator
US5614710A (en) * 1995-06-07 1997-03-25 Electrocom Automation L.P. Dichotomous scan system for detection of overlapped objects
US5659396A (en) * 1995-06-07 1997-08-19 Electrocom Automation L.P. Dichotomous scan system for detection of edges of objects and overlapped objects having relatively uniform surfaces
US5841540A (en) * 1995-06-07 1998-11-24 Siemens Electrocom L.P. Dichotomous scan system for detection of edges of objects and overlapped objects having relatively uniform surfaces
EP0921083A3 (en) * 1997-11-05 1999-08-04 Ncr International Inc. System for detecting superposed sheets
US6082732A (en) * 1997-11-05 2000-07-04 Ncr Corporation System for detecting superposed sheets
US6241244B1 (en) * 1997-11-28 2001-06-05 Diebold, Incorporated Document sensor for currency recycling automated banking machine
US6568591B2 (en) 1997-11-28 2003-05-27 Diebold, Incorporated Document sensor for currency recycling automated banking machine
US6463824B1 (en) * 2000-02-29 2002-10-15 S-B Power Tool Company Right angle attachment for power hand tool
US20070251192A1 (en) * 2006-04-27 2007-11-01 Pitney Bowes Incorporated Method of sensing pack insertion at crease line of envelope
US8234845B2 (en) * 2006-04-27 2012-08-07 Pitney Bowes Inc. Method of sensing pack insertion at crease line of envelope

Also Published As

Publication number Publication date
DE2116803A1 (de) 1971-10-28
FR2089733A5 (enExample) 1972-01-07
BE765366A (fr) 1971-10-06
NL7104413A (enExample) 1971-10-08
CA930052A (en) 1973-07-10
GB1342656A (en) 1974-01-03

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