EP0130825A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method and apparatus for sensing sheets
Assignee: De la Rue Systems Ltd
•
Filing: 1984-06-29
•
Granted: —
•
Expires: 2004-06-29
Abstract
Abstract Apparatus for sensing the passage of sheets (59) through a nip (58), comprises a pair of guide surfaces defining the nip (58); means (15, 18) for passing sheets (59) through the nip (58); and sensing means formed by pairs of light emitting diodes (48) and phototransistors (49) for sensing the deflection of one guide surface relatively to the other. Monitoring means (52, 53, 54) are provided for monitoring the output of the sensing means (48, 49) and for storing a guide surface profile corresponding to the sensing means output when no sheet (59) is present. Comparison means (55) compares subsequent output of the sensing means (52, 53) with the stored profile; and detection means (53) detects the presence of a sheet in the nip (58) only when the difference between the subsequent output and the stored profiles is substantially uniform.
Inventors
- 👤 Martin Lane
- 👤 Michael Roger Croset
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 19:35
CPC Classifications
B; B65; B65H; B65H43/00; B65H43/08; B65H7/00; B65H7/02; B65H7/06; B65H7/12; B65H2404/00; B65H2404/10; B65H2404/14; B65H2511/00; B65H2511/10; B65H2511/17; B65H2511/50; B65H2511/52; B65H2511/524; B65H2553/00; B65H2553/40; B65H2553/41; B65H2553/412; B65H2701/00; B65H2701/10; B65H2701/19; B65H2701/1912
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
117 words
A method of sensing the passage of sheets (59) through a nip (58) between a pair of guide surfaces by sensing with sensing means (48,49) the relative deflection between the guide surfaces in response to the presence of a sheet in the nip (58), characterised by a) monitoring the output of the sensing means (48,49) when no sheet (59) is present to generate and store a guide surface profile (57,57'); b) monitoring subsequent output of the sensing means; c) comparing the subsequent output with the stored profile (57,57'); and d) sensing the presence of a sheet (59) in the nip (58) only when there is a substantially uniform difference between the subsequent output and the stored profile.
Claim 2
Independent Claim
117 words
A method of sensing the passage of sheets (59) through a nip (58) between a pair of guide surfaces by sensing with sensing means (48,49) the relative deflection between the guide surfaces in response to the presence of a sheet in the nip (58), characterised by a) monitoring the output of the sensing means (48,49) when no sheet (59) is present to generate and store a guide surface profile (57,57'); b) monitoring subsequent output of the sensing means; c) comparing the subsequent output with the stored profile (57,57'); and d) sensing the presence of a sheet (59) in the nip (58) only when there is a substantially uniform difference between the subsequent output and the stored profile.
Claim 3
Dependent Claim
25 words
A method according to claim 1, wherein the monitoring portion of step a) is carried out after the passage of a batch of sheets (59).
Claim 4
Dependent Claim
33 words
A method according to claim 1 or claim 2, wherein the output of the sensing means (48,49) is monitored at a number of equal spatial intervals in one pass of the guide surfaces.
Claim 5
Independent Claim
37 words
A method according to any of the preceding claims, wherein the presence of a sheet (59) in the nip (58) is sensed when the difference between the subsequent output and the stored profile exceeds a threshold (63).
Claim 6
Dependent Claim
71 words
A method according to claim 4, wherein after the guide surface profile (57,57') has been stored, the method comprises carrying out steps b - d with a relatively small threshold (62) until the difference detected in steps c and d exceeds the threshold, generating a new threshold (63) substantially equal to half the difference determined in steps c and d, and thereafter repeating steps b to d with the new threshold.
Claim 7
Dependent Claim
37 words
A method according to claim 5, wherein the method further comprises determining whether the difference between the output of the sensing means (48,49) and the stored profile is more than three times the new threshold (63) .
Claim 8
Dependent Claim
130 words
Apparatus for sensing the passage of sheets (59) through a nip (58), the apparatus comprising a pair of guide surfaces defining the nip (58); means (15,18) for passing sheets (59) through the nip (58); and sensing means (48,49) for sensing the deflection of one guide surface relatively to the other; characterised by monitoring means (52,53,54) for monitoring the output of the sensing means (48,49) and for storing a guide surface profile corresponding to the sensing means output when no sheet (59) is present; comparison means (55) for comparing subsequent output of the sensing means with the stored profile; and detection means (53) for detecting the presence of a sheet in the nip (58) only when there is a substantially uniform difference between the subsequent output and the stored profile .
Claim 9
Dependent Claim
130 words
Apparatus for sensing the passage of sheets (59) through a nip (58), the apparatus comprising a pair of guide surfaces defining the nip (58); means (15,18) for passing sheets (59) through the nip (58); and sensing means (48,49) for sensing the deflection of one guide surface relatively to the other; characterised by monitoring means (52,53,54) for monitoring the output of the sensing means (48,49) and for storing a guide surface profile corresponding to the sensing means output when no sheet (59) is present; comparison means (55) for comparing subsequent output of the sensing means with the stored profile; and detection means (53) for detecting the presence of a sheet in the nip (58) only when there is a substantially uniform difference between the subsequent output and the stored profile .
Claim 10
Dependent Claim
15 words
Banknote feeding apparatus including apparatus for sensing the passage of banknotes according to claim 7.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.