GB1266897A - - Google Patents
Info
- Publication number
- GB1266897A GB1266897A GB1266897DA GB1266897A GB 1266897 A GB1266897 A GB 1266897A GB 1266897D A GB1266897D A GB 1266897DA GB 1266897 A GB1266897 A GB 1266897A
- Authority
- GB
- United Kingdom
- Prior art keywords
- voltage
- original
- circuit
- amplifier
- component
- 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
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
- B41C1/00—Forme preparation
- B41C1/14—Forme preparation for stencil-printing or silk-screen printing
- B41C1/141—Forme preparation for stencil-printing or silk-screen printing by cutting or perforation with mechanical means; Electrical spark cutting
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Facsimile Image Signal Circuits (AREA)
- Facsimile Scanning Arrangements (AREA)
Abstract
1,266,897. Facsimile apparatus. ZEUTHEN & AAGAARD A.S. 11 March, 1969 [14 March, 1968], No. 12832/69. Heading H4F. In a device for producing a perforated laminar printing forme 3, a control signal derived from scanning an original 2, using a light source L and receiver PHC, is fed to a summation amplifier AMPL preceding a trigger TR which connects and disconnects a voltage from an oscillator OSC to a perforation electrode PE, and the device is characterized in that the amplifier is also supplied with a threshold reference voltage from a circuit S, adjustable to determine e.g. the separation of those parts of the original which are to be regarded and reproduced as wholly black and those parts which are to be subject to grey tone modulation, a sawtooth modulation voltage on a constant D.C. baseline voltage, from a circuit G, the amplitude of the sawtooth voltage being adjustable to determine e.g. the separation of those parts of the original to be regarded as wholly white and those parts subject to grey tone modulation, and an automatically controlled calibration voltage from a circuit REG to compensate for changes in operating conditions such as mains voltage variation, and changes in the optical system. The forme 2 and original 3 are mounted on a rotatable and displaceable drum 1 together with a reference original GB, and a permanent magnet PM on the drum induces a signal in a coil PV when the reference original GB is to be scanned, so that a switch F, shown as mechanical but in practice an electronic switch, disconnects circuits S and G from the amplifier and connects the output of trigger TR to the circuit REG to adjust the calibration voltage output for the next scan of the original, as described more particularly in Specification 1,194,717. The light receiver PHC is arranged to give a voltage output with a first component whose variation for a given variation in light intensity is practically constant even if the total voltage output varies e.g. due to a second, temperature dependent, component, so that the second component is automatically compensated by the circuit REG and a fixed relationship between the amplitude of the modulation signal and the first, light sensitive, component, is established. Thus the receiver PHC may be a photo-diode, a photo-semi-conductor having a linear sensitivity characteristic, or a photosensitive component in series with semi-conductor diodes e.g. of silicon. Fig. 7 (not shown) shows a photoconductive component which does not give the desired dependence between the light intensity and voltage, in series with two diodes, across which is developed the desired output voltage. In the circuit shown in Fig. 1, the oscillator OSC feeds the electrode PE via an adjusting circuit V, an electronic switch SW 1 controlled by the trigger TR and an amplifier PA, and also energizes the lamp L. According to the adjustment of an inverting circuit P/N, the control signal is adapted for positive or negative reproduction. In a modification, Fig. 2 (not shown), the output of the amplifier AMPL is fed back to the regulating circuit REG during scanning of the reference original, and the trigger TR acts directly on the amplifier PA.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DK108568A DK118275B (en) | 1968-03-14 | 1968-03-14 | Apparatus for electrically perforating a stencil. |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1266897A true GB1266897A (en) | 1972-03-15 |
Family
ID=8100828
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1266897D Expired GB1266897A (en) | 1968-03-14 | 1969-03-11 |
Country Status (5)
Country | Link |
---|---|
DE (1) | DE1912596C3 (en) |
DK (1) | DK118275B (en) |
FR (1) | FR2003888A1 (en) |
GB (1) | GB1266897A (en) |
SE (1) | SE347123B (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE7607272U1 (en) * | 1976-03-10 | 1976-10-14 | Schnuelle Geb. Esselbruegge, Helga, 4830 Guetersloh | CUFF FOR FLOWER POTS, PLANT BOWLS OR SIMILAR VESSELS |
ATE167111T1 (en) * | 1996-04-19 | 1998-06-15 | Schablonentechnik Kufstein Ag | HALFTONE STENCIL AND METHOD AND DEVICE FOR PRODUCING IT |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DK94162C (en) * | 1959-01-23 | 1962-08-20 | Zeuthen & Aagaard As | Method for perforating electrostencil and device for electrically perforating electrostatic apparatus in accordance with the method. |
FR1457309A (en) * | 1965-05-13 | 1966-01-24 | Colos Soc | Electronic method and device for reproducing halftones on electrostencil |
DK111083B (en) * | 1966-06-03 | 1968-05-27 | Zeuthen & Aagaard As | Machine for perforating a stencil by electric means. |
-
1968
- 1968-03-14 DK DK108568A patent/DK118275B/en unknown
-
1969
- 1969-03-11 GB GB1266897D patent/GB1266897A/en not_active Expired
- 1969-03-12 DE DE19691912596 patent/DE1912596C3/en not_active Expired
- 1969-03-12 SE SE343269A patent/SE347123B/xx unknown
- 1969-03-13 FR FR6907110A patent/FR2003888A1/fr not_active Withdrawn
Also Published As
Publication number | Publication date |
---|---|
DK118275B (en) | 1970-07-27 |
DE1912596A1 (en) | 1969-10-09 |
FR2003888A1 (en) | 1969-11-14 |
DE1912596C3 (en) | 1981-12-10 |
DE1912596B2 (en) | 1981-04-09 |
SE347123B (en) | 1972-07-24 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
PCNP | Patent ceased through non-payment of renewal fee |