Patent US6040923A successfully refreshed from Google Patents.
US6040923A
Expired / Lapsed
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Transfer control apparatus for optical image reading apparatus
Assignee: Fujitsu Ltd
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Filing: 1997-06-11
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Granted: 2000-03-21
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Expires: 2017-06-11
Abstract
Abstract A transmission-type sensor and a reflection-type sensor are provided for detecting paper at the same position of a transfer path, and a sensor mode used according to kinds, printed conditions, and the like of the paper is selected. A transmission-type sensor processing unit and a reflection-type sensor processing unit are provided according to the transmission-type sensor and reflection-type sensor. The paper pass detection unit detects presence of paper, and decides presence of double-feed for the second and later sheets of paper based on detection information of the first sheet of paper.
Inventors
- 👤 Yoshihiro Takashimizu
- 👤 Yoshio Tabata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:25
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/00681; H04N1/00684; H04N1/00687; H04N1/00694; H04N1/00702; H04N1/00705; H04N1/00708; H04N1/00729; H04N1/00734; H04N1/00742; H04N1/00745; G; G03; G03G; G03G2215/00; G03G2215/00362; G03G2215/00535; G03G2215/00548
Claims Analysis
Total Claims: 40
Claim 1
Independent Claim
380 words
A paper transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using one or more sensors, and optically reads an image on the paper, the paper transfer control apparatus comprising: a transmission-type sensor detecting the paper; a reflection-type sensor detecting the paper; a sensor mode selecting unit for selecting one of said sensors; a transmission-type sensor processing unit performing paper detection processing for said transmission-type sensor, based on a detection signal of the transmission-type sensor when selected by said sensor mode selecting unit; and a reflection-type sensor processing unit performing paper detection processing for said reflection-type sensor, based on a detection signal of the reflection-type sensor when selected by said sensor mode selecting unit, wherein each of said transmission-type sensor processing unit and said reflection-type sensor processing unit comprises: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels regarding front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of paper based on the sensor detection level, wherein said double-feed detection processing unit of said transmission-type sensor processing unit comprises: a criterion-level setting unit for obtaining a sensor output L at the time of transferring the first sheet of paper in a criterion-level setting range having an upper limit Lup and a lower limit Ldown based on a quantity of light transmitted from a base color portion of paper by controlling light emission current of a sensor, detecting a sensor output corresponding to the quantity of light transmitted from the base color portion of the paper within the criterion-level setting range, and setting a criterion-level for double-feed decision, L0; and a double-feed decision unit for setting a lower decision limit Lr1 and an upper decision limit Lr2 based on the criterion-level for double-feed decision, L0 that is set by said criterion-level setting unit, deciding to be double-feed of paper presently being transferred if the sensor output L becomes equal to or lower than said lower decision limited Lr1 when the second and later sheets of paper are transferred, and deciding to be double-feed of the first sheet of paper if the sensor output L becomes equal to or larger than said upper decision limit Lr2.
Claim 2
Dependent Claim
380 words
A paper transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using one or more sensors, and optically reads an image on the paper, the paper transfer control apparatus comprising: a transmission-type sensor detecting the paper; a reflection-type sensor detecting the paper; a sensor mode selecting unit for selecting one of said sensors; a transmission-type sensor processing unit performing paper detection processing for said transmission-type sensor, based on a detection signal of the transmission-type sensor when selected by said sensor mode selecting unit; and a reflection-type sensor processing unit performing paper detection processing for said reflection-type sensor, based on a detection signal of the reflection-type sensor when selected by said sensor mode selecting unit, wherein each of said transmission-type sensor processing unit and said reflection-type sensor processing unit comprises: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels regarding front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of paper based on the sensor detection level, wherein said double-feed detection processing unit of said transmission-type sensor processing unit comprises: a criterion-level setting unit for obtaining a sensor output L at the time of transferring the first sheet of paper in a criterion-level setting range having an upper limit Lup and a lower limit Ldown based on a quantity of light transmitted from a base color portion of paper by controlling light emission current of a sensor, detecting a sensor output corresponding to the quantity of light transmitted from the base color portion of the paper within the criterion-level setting range, and setting a criterion-level for double-feed decision, L0; and a double-feed decision unit for setting a lower decision limit Lr1 and an upper decision limit Lr2 based on the criterion-level for double-feed decision, L0 that is set by said criterion-level setting unit, deciding to be double-feed of paper presently being transferred if the sensor output L becomes equal to or lower than said lower decision limited Lr1 when the second and later sheets of paper are transferred, and deciding to be double-feed of the first sheet of paper if the sensor output L becomes equal to or larger than said upper decision limit Lr2.
Claim 3
Dependent Claim
91 words
A paper transfer control apparatus according to claim 1, wherein said criterion-level setting unit detains the sensor output in said criterion-level setting range by decreasing light emission current of a sensor if the sensor output at the time of a front-edge of paper passing is not smaller than said upper limit Lup, and pulls a sensor output in said criterion-level setting range by increasing light emission current of the sensor if the sensor output at the time of a front-edge of paper passing is not larger than said lower limit Ldown.
Claim 4
Dependent Claim
49 words
A paper transfer control apparatus according to claim 2, wherein said criterion-level setting unit increases a changing speed at the time of decreasing light emission current of a sensor, and on the contrary, decreases the changing speed at the time of increasing the light emission current of the sensor.
Claim 5
Dependent Claim
51 words
A paper transfer control apparatus according to claim 1, wherein said criterion-level setting unit inhibits control of light emission current for pulling a sensor output in said criterion-level setting range until a counted value of pulses passing through paper since detection of a front-edge of the paper reaches a predetermined value.
Claim 6
Dependent Claim
68 words
A paper transfer control apparatus according to claim 1, wherein said criterion-level setting unit starts peak hold of a sensor output in a status that control of light emission current is stopped, when the sensor output is pulled in said criterion-level setting range continuously during a predetermined period, and sets a peak hold value just before detecting a back-edge of paper as a criterion-level for double-feed decision, L0.
Claim 7
Dependent Claim
54 words
A paper transfer control apparatus according to claim 5, wherein said criterion-level setting unit restarts control of light emission current and also inhibits peak hold if a sensor output goes out of said criterion-level setting range during the peak hold after said criterion-level setting unit pulled the sensor output in said criterion-level setting range.
Claim 8
Dependent Claim
52 words
A paper transfer control apparatus according to claim 5, wherein said double-feed decision unit sets a period from the time of detecting a front-edge of paper to the time of counting a number of pulses passing through the first sheet of paper, P0, which was obtained beforehand, as a double-feed decision period.
Claim 9
Dependent Claim
37 words
A paper transfer control apparatus according to claim 7, wherein said double-feed decision unit inhibits double-feed decision during a period when first predetermined number of pulses passing through paper, Pa is counted, in said double-feed decision period.
Claim 10
Dependent Claim
89 words
A paper transfer control apparatus according to claim 1, wherein said double-feed decision unit decides to be double-feed of paper presently passing, if a number of pulses passing through the paper since a front-edge of the paper was detected exceeds a value, (P0+α) obtained by adding a first number of pulses passing through the paper, P0, which was obtained beforehand, and a predetermined error range α, and even if a sensor output is within a range between said lower limit Lr1 and said upper limit Lr2 of double-feed decision.
Claim 11
Dependent Claim
268 words
A paper transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using one or more sensors, and optically reads an image on the paper, the paper transfer control apparatus comprising: a transmission-type sensor detecting the paper; a reflection-type sensor detecting the paper; a sensor mode selecting unit for selecting one of said sensors; a transmission-type sensor processing unit performing paper detection processing for said transmission-type sensor, based on a detection signal of the transmission-type sensor when selected by said sensor mode selecting unit; and a reflection-type sensor processing unit performing paper detection processing for said reflection-type sensor, based on a detection signal of the reflection-type sensor when selected by said sensor mode selecting unit, wherein each of said transmission-type sensor processing unit and said reflection-type sensor processing unit comprises: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels regarding front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of paper based on the sensor detection level, wherein said paper pass detection processing unit of said reflection-type sensor processing unit obtains an offset value Pa from a front-edge of the paper, when a sensor output reaches a slice level S, using a changing rate at the time of the sensor output reaching said predetermined slice level S after the front-edge of the paper passing, and corrects a value used for decision at the time of the front-edge of the paper reaching a reading point in a down-flow side, using the offset value Pa.
Claim 12
Dependent Claim
268 words
A paper transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using one or more sensors, and optically reads an image on the paper, the paper transfer control apparatus comprising: a transmission-type sensor detecting the paper; a reflection-type sensor detecting the paper; a sensor mode selecting unit for selecting one of said sensors; a transmission-type sensor processing unit performing paper detection processing for said transmission-type sensor, based on a detection signal of the transmission-type sensor when selected by said sensor mode selecting unit; and a reflection-type sensor processing unit performing paper detection processing for said reflection-type sensor, based on a detection signal of the reflection-type sensor when selected by said sensor mode selecting unit, wherein each of said transmission-type sensor processing unit and said reflection-type sensor processing unit comprises: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels regarding front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of paper based on the sensor detection level, wherein said paper pass detection processing unit of said reflection-type sensor processing unit obtains an offset value Pa from a front-edge of the paper, when a sensor output reaches a slice level S, using a changing rate at the time of the sensor output reaching said predetermined slice level S after the front-edge of the paper passing, and corrects a value used for decision at the time of the front-edge of the paper reaching a reading point in a down-flow side, using the offset value Pa.
Claim 13
Dependent Claim
37 words
A paper transfer control apparatus according to claim 10, wherein a paper pass detection processing unit of said reflection-type sensor processing unit prepares relation between said changing rate and an offset value Pa beforehand as table information.
Claim 14
Dependent Claim
91 words
A paper transfer control apparatus according to claim 10, wherein a paper pass detection processing unit of said reflection-type sensor processing unit uses a differential (Lt-S), which is obtained by subtracting a predetermined slice level S from a sensor output Lt at the time when a predetermined number of pulses passing through paper, Pd from the time when the sensor output reached the slice level S is counted, as a changing rate at the time when the sensor output reaches the predetermined slice level S after a front-edge of paper passed.
Claim 15
Dependent Claim
66 words
A paper transfer control apparatus according to claim 10, wherein a paper pass detection processing unit of said reflection-type sensor processing unit uses a derivative value of a sensor output, dL/dt at the time when the sensor output reaches the slice level S, as a changing rate at the time when the sensor output reaches the predetermined slice level S after a front-edge of paper passed.
Claim 16
Dependent Claim
107 words
A paper transfer control apparatus according to claim 10, wherein a paper pass detection processing unit of said reflection-type sensor processing unit makes a front-edge counter P1 start counting pulses passing through paper at the time when a sensor output increases to a predetermined slice level S after a front-edge of paper passed, corrects the count by adding said offset correction value Pa, and decides arrival of the front-edge of the paper to a reading point when a counted value of the front-edge counter P1 after the correction reaches a predetermined number of pulses passing through the paper, P0 from a sensor position to the reading point.
Claim 17
Dependent Claim
109 words
A paper transfer control apparatus according to claim 10, wherein a paper pass detection processing unit of said reflection-type sensor processing unit makes a back-edge counter P2 start counting pulses passing through paper at the time when a sensor output decreases to a predetermined slice level S just before the back-edge of the paper passes, corrects the count by subtracting said offset correction value Pa, and decides arrival of the back-edge of the paper to a reading point when a counted value of the back-edge counter P2 after the correction reaches a predetermined number of pulses passing through the paper, P0 from a sensor position to the reading point.
Claim 18
Dependent Claim
318 words
A transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using one or more sensors, and optically reads an image on the paper, the paper transfer control apparatus comprising: a transmission-type sensor detecting the paper; a reflection-type sensor detecting the paper; a sensor mode selecting unit for selecting one of said sensors; a transmission-type sensor processing unit performing paper detection processing for said transmission-type sensor, based on a detection signal of the transmission-type sensor when selected by said sensor mode selecting unit; and a reflection-type sensor processing unit performing paper detection processing for said reflection-type sensor, based on a detection signal of the reflection-type sensor when selected by said sensor mode selecting unit, wherein each of said transmission-type sensor processing unit and said reflection-type sensor processing unit comprises: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels regarding front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of paper based on the sensor detection level, wherein said double-feed detection processing unit of said transmission-type sensor processing unit comprises: a decision range setting unit for setting an upper limit (P0+α) and a lower limit (P0-α) by adding and subtracting a predetermined error range α to/from a number of pulses passing through the paper from a front-edge of the paper to a back-edge, P0, which were detected at the time when the first sheet of the paper was transferred; and a double-feed decision unit for deciding to be double-feed of paper presently passing, if a counted value of pulses passing through the paper at the time when the second or later sheet of paper is transferred exceeds said upper limit (P0+α), and deciding to be the double-feed of the first sheet of paper, if the counted value becomes smaller than said lower limit (P0-α).
Claim 19
Dependent Claim
318 words
A transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using one or more sensors, and optically reads an image on the paper, the paper transfer control apparatus comprising: a transmission-type sensor detecting the paper; a reflection-type sensor detecting the paper; a sensor mode selecting unit for selecting one of said sensors; a transmission-type sensor processing unit performing paper detection processing for said transmission-type sensor, based on a detection signal of the transmission-type sensor when selected by said sensor mode selecting unit; and a reflection-type sensor processing unit performing paper detection processing for said reflection-type sensor, based on a detection signal of the reflection-type sensor when selected by said sensor mode selecting unit, wherein each of said transmission-type sensor processing unit and said reflection-type sensor processing unit comprises: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels regarding front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of paper based on the sensor detection level, wherein said double-feed detection processing unit of said transmission-type sensor processing unit comprises: a decision range setting unit for setting an upper limit (P0+α) and a lower limit (P0-α) by adding and subtracting a predetermined error range α to/from a number of pulses passing through the paper from a front-edge of the paper to a back-edge, P0, which were detected at the time when the first sheet of the paper was transferred; and a double-feed decision unit for deciding to be double-feed of paper presently passing, if a counted value of pulses passing through the paper at the time when the second or later sheet of paper is transferred exceeds said upper limit (P0+α), and deciding to be the double-feed of the first sheet of paper, if the counted value becomes smaller than said lower limit (P0-α).
Claim 20
Dependent Claim
25 words
A paper transfer control apparatus according to claim 16, wherein said decision range setting unit sets said error allowance α to be variable, if necessary.
Claim 21
Dependent Claim
263 words
A paper transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using a transmission-type sensor, and optically reads an image on the paper, the paper transfer control apparatus comprising: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels at front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of the paper based on a sensor detection level, wherein said double-feed detection processing unit comprises: a criterion-level setting unit for pulling a sensor output L in a criterion-level setting range having an upper limit Lup and a lower limit Ldown based on a quantity of light transmitted from a base color portion of the paper when the first sheet of paper is transferred, detecting a sensor output corresponding to the quantity of light transmitted from the base color portion of the paper within the criterion-level setting range, and setting the sensor output as a criterion level for double-feed decision, L0; and a double-feed decision unit for setting a lower decision limit Lr1 and an upper decision limit Lr2 based on the criterion-level for double-feed decision, L0 set by said criterion-level setting unit, deciding to be double-feed of paper presently transferred if a sensor output at the time when the second and later sheets of paper are transferred is not larger than said lower limit Lr1, and setting to be double-feed of the first sheet of paper if the sensor output is not smaller than said upper limit Lr2.
Claim 22
Dependent Claim
263 words
A paper transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using a transmission-type sensor, and optically reads an image on the paper, the paper transfer control apparatus comprising: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels at front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of the paper based on a sensor detection level, wherein said double-feed detection processing unit comprises: a criterion-level setting unit for pulling a sensor output L in a criterion-level setting range having an upper limit Lup and a lower limit Ldown based on a quantity of light transmitted from a base color portion of the paper when the first sheet of paper is transferred, detecting a sensor output corresponding to the quantity of light transmitted from the base color portion of the paper within the criterion-level setting range, and setting the sensor output as a criterion level for double-feed decision, L0; and a double-feed decision unit for setting a lower decision limit Lr1 and an upper decision limit Lr2 based on the criterion-level for double-feed decision, L0 set by said criterion-level setting unit, deciding to be double-feed of paper presently transferred if a sensor output at the time when the second and later sheets of paper are transferred is not larger than said lower limit Lr1, and setting to be double-feed of the first sheet of paper if the sensor output is not smaller than said upper limit Lr2.
Claim 23
Dependent Claim
78 words
A paper transfer control apparatus according to claim 18, wherein said criterion-level setting unit pulls a sensor output in said criterion-level setting range by decreasing light emission current of a sensor if the sensor output is equal to or larger than said upper limit Lup, and pulls a sensor output in said criterion-level setting range by increasing the light emission current of the sensor if the sensor output is equal to or smaller than said lower limit Ldown.
Claim 24
Dependent Claim
49 words
A paper transfer control apparatus according to claim 18, wherein said criterion-level setting unit increases a changing speed at the time of decreasing light emission current of a sensor, and on the contrary, decreases the changing speed at the time of increasing the light emission current of the sensor.
Claim 25
Dependent Claim
51 words
A paper transfer control apparatus according to claim 18, wherein said criterion-level setting unit inhibits control of light emission current for pulling a sensor output in said criterion-level setting range until a counted value of pulses passing through paper since detection of a front-edge of the paper reaches a predetermined value.
Claim 26
Dependent Claim
68 words
A paper transfer control apparatus according to claim 18, wherein said criterion-level setting unit starts peak hold of a sensor output in a status that control of light emission current is stopped, when the sensor output is pulled in said criterion-level setting range continuously during a predetermined period, and sets a peak hold value just before detecting a back-edge of paper as a criterion-level for double-feed decision, L0.
Claim 27
Dependent Claim
54 words
A paper transfer control apparatus according to claim 22, wherein said criterion-level setting unit restarts control of light emission current and also inhibits peak hold if a sensor output goes out of said criterion-level setting range during the peak hold after said criterion-level setting unit pulled the sensor output in said criterion-level setting range.
Claim 28
Dependent Claim
52 words
A paper transfer control apparatus according to claim 18, wherein said double-feed decision unit sets a period from the time of detecting a front-edge of paper to the time of counting a number of pulses passing through the first sheet of paper, P0, which was obtained beforehand, as a double-feed decision period.
Claim 29
Dependent Claim
38 words
A paper transfer control apparatus according to claim 24, wherein said double-feed decision unit inhibits double-feed decision during a period when a first predetermined number of pulses passing through paper, Pa is counted, in said double-feed decision period.
Claim 30
Dependent Claim
90 words
A paper transfer control apparatus according to claim 18, wherein said double-feed decision unit further decides to be double-feed of paper presently passing, if a number of pulses passing through the paper since a front-edge of the paper was detected exceeds a value (P0+α) obtained by adding a first number of pulses passing through the paper, P0, which was obtained beforehand, and a predetermined error range α, and even if a sensor output is within a range between said lower limit Lr1 and said upper limit Lr2 of double-feed decision.
Claim 31
Dependent Claim
162 words
A paper transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using a reflection-type sensor, and optically reads an image on the paper, the paper transfer control apparatus comprising: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels at front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of paper based on a sensor detection level, wherein said paper pass detection processing unit obtains an offset value Pa from a front-edge of the paper, when a sensor output reaches a slice level S, using a changing rate at the time of the sensor output reaching said predetermined slice level S after the front-edge of the paper passing, and corrects a value used for decision at the time of the front-edge of the paper reaching a reading point in a down-flow side, using the offset value Pa.
Claim 32
Dependent Claim
162 words
A paper transfer control apparatus used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using a reflection-type sensor, and optically reads an image on the paper, the paper transfer control apparatus comprising: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels at front and back edges of the paper; and a double-feed detection processing unit for detecting double-feed of paper based on a sensor detection level, wherein said paper pass detection processing unit obtains an offset value Pa from a front-edge of the paper, when a sensor output reaches a slice level S, using a changing rate at the time of the sensor output reaching said predetermined slice level S after the front-edge of the paper passing, and corrects a value used for decision at the time of the front-edge of the paper reaching a reading point in a down-flow side, using the offset value Pa.
Claim 33
Dependent Claim
37 words
A paper transfer control apparatus according to claim 27, wherein a paper pass detection processing unit of said reflection-type sensor processing unit prepares relation between said changing rate and an offset value Pa beforehand as table information.
Claim 34
Dependent Claim
91 words
A paper transfer control apparatus according to claim 27, wherein a paper pass detection processing unit of said reflection-type sensor processing unit uses a differential (Lt-S), which is obtained by subtracting a predetermined slice level S from a sensor output Lt at the time when a predetermined number of pulses passing through paper, Pd from the time when the sensor output reached the slice level S is counted, as a changing rate at the time when the sensor output reaches the predetermined slice level S after a front-edge of paper passed.
Claim 35
Dependent Claim
66 words
A paper transfer control apparatus according to claim 27, wherein a paper pass detection processing unit of said reflection-type sensor processing unit uses a derivative value of a sensor output, dL/dt at the time when a sensor output reaches a slice level S, as a changing rate at the time when the sensor output reaches the predetermined slice level S after a front-edge of paper passed.
Claim 36
Dependent Claim
107 words
A paper transfer control apparatus according to claim 27, wherein a paper pass detection processing unit of said reflection-type sensor processing unit makes a front-edge counter P1 start counting pulses passing through paper at the time when a sensor output increases to a predetermined slice level S after a front-edge of paper passed, corrects the count by adding said offset correction value Pa, and decides arrival of the front-edge of the paper to a reading point when a counted value of the front-edge counter P1 after the correction reaches a predetermined number of pulses passing through the paper, P0 from a sensor position to the reading point.
Claim 37
Dependent Claim
108 words
A paper transfer control apparatus according to claim 27, wherein a paper pass detection processing unit of said reflection-type sensor processing unit makes a back-edge counter P2 start counting pulses passing through paper at the time when a sensor output decreases to a predetermined slice level S just before a back-edge of paper passes, corrects the count by subtracting said offset correction value Pa, and decides arrival of the back-edge of the paper to a reading point when a counted value of the back-edge counter P2 after the correction reaches a predetermined number of pulses passing through the paper, P0 from a sensor position to the reading point.
Claim 38
Dependent Claim
211 words
A paper transfer control apparatus, used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using a reflection-type sensor, and optically reads an image on the paper, the paper transfer control apparatus comprising: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels at front and back edges of paper; and a double-feed detection processing unit for detecting double-feed of paper based on a sensor detection level, wherein said double-feed detection processing unit comprises: a decision range setting unit for setting an upper limit (P0+α) and a lower limit (P0-α) by adding and subtracting a predetermined error range α to/from a number of pulses passing through the paper from a front-edge of the paper to a back-edge, P0, which were detected at the time when the first sheet of the paper was transferred; and a double-feed decision unit for deciding to be double-feed of paper presently passing, if a counted value of pulses passing through the paper at the time when the second or later sheet of paper is transferred exceeds said upper limit (P0+α), and deciding to be double-feed of the first sheet of paper, if the counted value becomes smaller than said lower limit (P0-α).
Claim 39
Dependent Claim
211 words
A paper transfer control apparatus, used for optical image reading apparatus that detects paper, which is transferred by a transfer mechanism, using a reflection-type sensor, and optically reads an image on the paper, the paper transfer control apparatus comprising: a paper pass detection processing unit for detecting information regarding paper pass from change of sensor detection levels at front and back edges of paper; and a double-feed detection processing unit for detecting double-feed of paper based on a sensor detection level, wherein said double-feed detection processing unit comprises: a decision range setting unit for setting an upper limit (P0+α) and a lower limit (P0-α) by adding and subtracting a predetermined error range α to/from a number of pulses passing through the paper from a front-edge of the paper to a back-edge, P0, which were detected at the time when the first sheet of the paper was transferred; and a double-feed decision unit for deciding to be double-feed of paper presently passing, if a counted value of pulses passing through the paper at the time when the second or later sheet of paper is transferred exceeds said upper limit (P0+α), and deciding to be double-feed of the first sheet of paper, if the counted value becomes smaller than said lower limit (P0-α).
Claim 40
Dependent Claim
25 words
A paper transfer control apparatus according to claim 33, wherein said decision range setting unit sets said error allowance α to be variable, if necessary.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2003-03-21 | 2003-09-20 | 2004-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-03-21 | 2007-09-20 | 2008-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-03-21 | 2011-09-20 | 2012-03-21 | $7700.00 | Window Closed / Lapsed |