Patent US7574661B2 successfully refreshed from Google Patents.
USRE28660E
Expired / Lapsed
US
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Discriminating apparatus for moving translucent sheets
Assignee: De la Rue Instruments Ltd
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Filing: 1973-09-17
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Granted: 1975-12-23
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Expires: 1993-09-17
Abstract
Abstract Apparatus for discriminating between moving translucent sheets comprising a sheet transportation means adapted to convey the sheets in spaced relationship along a flow-line, a photoelectric detection device sited on one side of the flow-line, a first differential amplifier having an input in circuit with the said detection device and adapted to produce a first output signal every time the photoelectric device detects attenuation of the light source in excess of a first predetermined value, and a second differential amplifier having an input also in circuit with the said detection device and adapted to produce a second output signal every time the photelectric device detects attenuation of the light source in excess of a second different predetermined value.
Inventors
- 👤 R S Pettet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:42
CPC Classifications
B; B65; B65H; B65H7/00; B65H7/02; B65H7/06; B65H7/12; B65H7/125; G; G06; G06M; G06M7/00; G06M7/02; G06M7/06; B65H2701/00; B65H2701/10; B65H2701/17; B65H2701/171; B65H2701/1712
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
170 words
Apparatus for discriminating between moving translucent sheets comprising a sheet transportation means for conveying the sheets in spaced relationship along a flow-line, a single photoelectric detection device positioned on one side of the flow-line and an associated light source positioned on the other side of the flow-line, a first differential amplifier means for producing a first output signal every time the photoelectric detection device detects attenuation of the light source in excess of a first predetermined value and having an input in circuit with the said detection device, and a second differential amplifier means for producing a second output signal every time the photoelectric detection device detects attenuation of the light source in excess of a second different predetermined value greater than said first predetermined value and having an input also in circuit with the said detection device and means for receiving and utilizing said output signals to discriminate between sheets which produce solely said first output signal and sheets which produce both said first and second output signals .
Claim 2
Dependent Claim
170 words
Apparatus for discriminating between moving translucent sheets comprising a sheet transportation means for conveying the sheets in spaced relationship along a flow-line, a single photoelectric detection device positioned on one side of the flow-line and an associated light source positioned on the other side of the flow-line, a first differential amplifier means for producing a first output signal every time the photoelectric detection device detects attenuation of the light source in excess of a first predetermined value and having an input in circuit with the said detection device, and a second differential amplifier means for producing a second output signal every time the photoelectric detection device detects attenuation of the light source in excess of a second different predetermined value greater than said first predetermined value and having an input also in circuit with the said detection device and means for receiving and utilizing said output signals to discriminate between sheets which produce solely said first output signal and sheets which produce both said first and second output signals .
Claim 3
Dependent Claim
96 words
Apparatus as claimed in claim 1 in which the first output signal serves to indicate the passage of (a) each single sheet having an opacity greater than the first predetermined value and less than the second predetermined value; (b) each folded single such sheet; (c) each single sheet having an opacity greater than the second predetermined value; and (d) each group of partially or wholly superposed single sheets having an opacity greater than the second predetermined value, and the second output signal serves to indicate the passage of any sheet in category (b), (c) or (d).
Claim 4
Dependent Claim
62 words
Apparatus as claimed in claim 1 in which said means for receiving and utilizing said output signals includes a sheet divertor (is) provided in the flow-line at a point downstream of the photoelectric detection device, said divertor being normally inoperative with respect to the sheets, but being operable to move into the flow-line every time the said second output signal is produced.
Claim 5
Dependent Claim
58 words
Apparatus as claimed in claim 5 in which said means for receiving and utilizing said output signals (additionally) includes length discrimination means for inhibiting actuation of the sheet divertor if the length of a sheet, or the overall length of a group of partially or wholly superposed sheets in the direction along the flow-line, exceeds a predetermined dimension.
Claim 6
Dependent Claim
143 words
Apparatus as claimed in claim (6 in) 1 which (the said) said means for receiving and utilizing said output signals includes a digital counter and length (discrimination) discriminator means (comprises) including (a pulse generator driven in unison with the sheet transportation) pulse-generating means, a pulse-counting means (,) and gate-switching means (for directing) arranged to be opened by said first output signal and to direct a train of pulses from the pulse generator to the pulse-counting means (whilst a sheet is present between the light source and the photoelectric detection device, and a count-discriminator for activating the sheet divertor only if less than a predetermined number of pulses are directed into) ; the pulse-counting means being operable to produce successively a first sheet-length-indicative datum count, a second sheet-length-indicative datum count and a digital count pulse for advancing said digital counter by one increment .
Claim 7
Dependent Claim
77 words
Apparatus as claimed in claim 7 in which the said pulse generator comprises a circumferentially perforated wheel positively driven by the sheet transportation means, a second light source disposed on one side of the wheel in alignment with the said perforations, a second photoelectric-detection means disposed on the other side of the wheel in alignment with the said perforations and operable upon rotation of the wheel to feed a train of pulses into the said gate-switching means.
Claim 8
Dependent Claim
89 words
Apparatus as claimed in claim (5) 7 so constructed that the (creation) termination of said first output signal (, and the termination thereof) before the attainment of the second datum count (and the creation of the said second output signal before the attainment of the first datum count) indicates the passage of one or more sheets having an over-all length within a predetermined range of lengths (plurality of overlapping sheets and further adapted to cause said divertor to move into the flow-line upon the passage of such sheets) .
Claim 9
Dependent Claim
89 words
Apparatus as claimed in claim (5) 7 so constructed that the (creation) termination of (the) said first output signal (and the termination thereof) after the attainment of the second datum count (and the creation of the second output signal after the attainment of the first datum count) indicates the passage of (a plurality of overlapping sheets, and further adapted to inhibit the movement of said divertor into the flow-line and to actuate a warning means) one or more sheets having an overall length in excess of a predetermined length.
Claim 10
Dependent Claim
29 words
Apparatus as claimed in claim 1 in which each differential amplifier means is provided with manually adjustable means adapted to permit the initial setting up of its output level.
Claim 11
Dependent Claim
51 words
Apparatus as claimed in claim 11 in which said input to said differential amplifier means includes one input dependent upon the effect of attenuated light upon said photo-electric device and a second input dependenT upon the effect of direct light upon said photoelectric device, said second input including said adjustable means.
Claim 12
Dependent Claim
74 words
Apparatus as claimed in claim 9 which additionally includes a sheet divertor in the flow-line downstream of the photo-electric detection device, said divertor being normally inoperative with respect to the sheets but being available to move into the flow-line everytime the second output signal is produced, and a count-pulse inhibit switch means operable in unison with every said divertor movement to prevent said digital count pulse from advancing said digital counter by one increment.
Claim 13
Dependent Claim
30 words
Apparatus as claimed in claim 10 additionally including a warning means operable on the passage of one or more sheets having an overall length in excess of the predetermined length.
Claim 14
Dependent Claim
67 words
Apparatus as claimed in claim 19 additionally including a sheet divertor in the flow-line downstream of the photoelectric detection device, said divertor being normally inoperative with respect to the sheets but being operable to move into the flow-line upon the production of the second output signal as a consequence of the passage of a sheet or sheets having an overall length within a predetermined range of lengths
Claim 15
Dependent Claim
34 words
Apparatus as claimed in claim 20 additionally including a count-pulse inhibit means operable in unison with every said divertor movement to prevent said digital count pulse from advancing said digital counter by one increment.
Claim 16
Dependent Claim
52 words
Apparatus as claimed in claim 21 additionally including means operable to maintain said divertor in its normal inoperative position upon the production of the second output signal as a consequence of the passage of one or more sheets having an overall length greater than any length within a predetermined range of lengths.
Claim 17
Dependent Claim
64 words
Apparatus as claimed in claim 1 wherein said means for receiving and utilizing said output signals includes a first digital counter coupled to said first differential amplifier means for receiving said first output signal therefrom and to be actuated thereby, and a second digital counter coupled to said second differential amplifier means for receiving said second output signal therefrom and to be actuaTed thereby.
Claim 18
Dependent Claim
38 words
Apparatus as claimed in claim 23 wherein said first digital counter is coupled to said second differential amplifier means for inhibiting a first output signal to said first digital counter upon the production of a second output signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-22 | 1979-06-23 | 1979-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-22 | 1983-06-23 | 1983-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-22 | 1987-06-23 | 1987-12-23 | $7700.00 | Window Closed / Lapsed |