CA1069366A - Copying device with electromagnetic cover release - Google Patents
Copying device with electromagnetic cover releaseInfo
- Publication number
- CA1069366A CA1069366A CA267,821A CA267821A CA1069366A CA 1069366 A CA1069366 A CA 1069366A CA 267821 A CA267821 A CA 267821A CA 1069366 A CA1069366 A CA 1069366A
- Authority
- CA
- Canada
- Prior art keywords
- cover
- electromagnet
- magnetic body
- circuit means
- magnetic
- 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
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
- G03B27/00—Photographic printing apparatus
- G03B27/32—Projection printing apparatus, e.g. enlarger, copying camera
- G03B27/52—Details
- G03B27/62—Holders for the original
- G03B27/6207—Holders for the original in copying cameras
- G03B27/6221—Transparent copy platens
- G03B27/6228—Platen covers
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Holders For Sensitive Materials And Originals (AREA)
- Exposure Or Original Feeding In Electrophotography (AREA)
Abstract
Abstract of the Disclosure A copying device provided with a glass plate and a co-operating cover and an improved locking mechanism for said cover comprising at least a permanent magnet combined with an electromagnet connected to a control circuit wherein the permanent magnet keeps the cover in the closed position against the glass plate, and at the end of the copying run the electromagnet is activated with a magnetic field thereby releasing the cover. This improved locking mechanism has the advantage over known mechanical mechanisms in that there is no wear on the components thereby increasing its reliability
Description
10f~93~;6 The invention relates to a copying device provided with a glass plate and a cooperating cover Eor keeping documents against the glass plate, a latching mechanism comprising at least one permanent magnet which keeps ; the cover in the closed position against the glass plate, a mechanism for unlatching the cover at the end of a copying run and a lifting device for lifting the cover after the unlatching.
Such a device is known from United States patent specification 3,888,581 or 3,888,582.
In this known device the cover in unlatched at the end of a copying run by slightly lifting the cover by means of a cam, as a result of which an air gap is made between the permanent magnet and the cooperating soft iron mass. Consequently the magnetic attraction between these two elements de-creases considerably, so that the force of the lifting device is sufficient for further opening the cover.
The disadvantage of this known device is, that the unlatching takes place with the aid of moving parts which must transfer a relatively high force. Therefore these parts are liable to wear, which after frequent use of the cover may cause the unlatching mechanism not to work reliably.
According to the present invention, there is provided in a device for covering originals during copying thereof by exposure on a transparent plate mounted in a frame of a photoco W ing apparatus, including a cover for pressing an original against said plate, means supporting said cover for swinging movement to and away from a closed position over said plate, means constantly exerting a force biasing said cover away from said plate, and disengageable means on said cover and said plate for ]atching said cover in closed position against the force of said biasing means, the improvement consisting in: said latching means comprising on one of said cover and said frame a permanently magnetic body, on the other of them a magnetically attractable body that confronts said magnetic body when said cover is in closed position and on either said cover or said frame an electromagnet the core of which is constituted by one of said bodies, said permanently magnetic body in the closed position of said cover attracting said attractable body -1- ~
B
:~Of~9~3~;
with a force exceeding the force of said biasing means, and means for generat-ing in said electromagnet an electromagnetic field counteracting the magnetic field of said magnetic body with a force sufficiently strong that the com-bined forces of said fields on said attractable body are exceeded by the force of said biasing means so that said biasing means will itself lift said cover away from said plate.
Thus, the magnetic force of attraction of the permanent magnet is reduced without the use of moving parts in such a way, that the cover can be lifted by the lifting device.
In a preferred embodiment a magnetic field is generated in the electromagnet during the copying run, which magnetic field has a polarity being equal to the polarity of the magnetic field of the permanent magnet.
Thereby the magnetic attraction can be increased so much, that it is very difficult to open the cover by hand, in which way the cover is pre-vented from being opened during the copying. In this way, when thicker objects, such as books, must be pressed against the glass plate, the magnetic force of attrac~ion is sufficient to guarantee an effective contact. This cannot happen by increasing the magnetic field strength of the permanent magnet, as it must still be possible to open the cover by hand before the beginning of the copying run.
Other characteristics and advantages of the invention will become clear from the following description whereby reference is made to the enclosed drawings, in which:
Figure 1 is a schematic section of a cover in which the locking mechanism according to the invention is applied.
Figure 2 is an electric scheme wherein the operation of the locking mechanism according to the invention can be controlled, and Figure 3 is a schematic time diagram of the signals which play a part in the scheme of Figure 2.
In Figure 1 a cover 2, cooperating with a glass plate 1, is schem-atically represented in section, as described in more details in the U.S.
patent No. 4,035,077 of applicant. The cover 2 can hinge round a shaft, in ~069366 order that it can be moved towards and away from the glass plate 1, whereby the shaft 43 is installed near a longitudinal edge 30 of the cover 2. As ; described in above-mentioned U.S. patent No. 4,035,077 a spring is installed on the shaft 43, which spring tries to turn the cover 2 away from the gLass plate.
Near the opposite longitudinal edge 25 of the cover 2 a block 150 of magnetizable material, for instance a soft iron core, is fixed against and in the lower side of this edge. In the frame 151 of the copying device on which the cover 2 is installed, an electromagnet 152 is fixed at a place which in the closed position of the cover, lies opposite to the block 150.
This electromagnet 152 consists of an electromagnetic coil 153 and a core 154 which in the embodiment represented consists of a permanent magnet.
The operation of the latching mechanism is as follows. In the closed position of the cover 2, the magnetic attraction between the permanent magnet 154 and the soft iron block 150 is sufficient to keep the cover in the closed position against the force of the spring acting on the shaft 43. In case sheetlike or thin originals lie on the glass plate, this magnetic force of attraction is also sufficient to keep these in good contact with the glass plate. As soon as the copying run is finished, a magnetic field is generated via the electromagnet 152, which magnetic field acts against the magnetic field of the permanent magnet. This counter-acting magnetic field has in any case been designed to be so strong that magnetic force of attraction between the block 150 and the permanent magnet 154 becomes weaker than the upward force which is exercised via the spring on the shaft 43, so that the cover turns upwards. As soon as the air gap between the block 150 and the permanent magnet has become great enough, the excitation of the electromagnet 152 can be stopped, as the magnetic attraction between block 150 and magnet 154 has become negligibly low. The original can now be exchanged and the cover can be closed by hand, after which the following copying run can be started.
In the case of thicker originals the electromagnet 152 can also be used for generating an additional magnetic attraction of the cover 2, by generating a magnetic field via the electromagnet 152, which magnetic field ~0693~;6 reinforces the magnetic field of the permanent magnet 154. This extra magnetic field can for instance be generated when pressing the print knob for starting the copying run.
In Figure 2 a circuit is representecl with which the above-described operation can be realized. Hereby it is accepted, that when starting the copying run a signal pulse PRINT is generated, whereby these signal pulses can be derived from the control system of the copying device, as described in more detail in U.S. patent No. 3,912,390. Thereby the signal END will be generated immediately after the exposure device is excited for the last time.
:
~, ,~
, -3a-101~93~
The electromagnet 152 is connected on the one part with the positive clamp of a diroct current source of for instance ~12 V, and on the other part via a transistor 160 with a reference tension or earth and via a transistor 151 with the positive clamp of a direct voltage sou~ce of for instance ~24 V.
The base of the transistor 161 is connected via an amplifier 162 with ~he set-output 163 of an RS-flip-flop 164, of which the set-input is connected with the signal-emitter END and the reset-input is connected with the signal-emitter PRINT.
The base of the transistor 160 is connected via an amplifier 165 with the output 167 of a monostable multivibrator 166, of which the input is connected with the signal-emitter END. The monostable multivibrator 166 lengthens the signalpulse END to a pulse of about 1 sec.
The operation of this electrical scheme is now as follows ~compare Figure 3). When the copying run is started (at the height of tl), the signal pulse PRINT is generated, as a resul~ of which the flip-flop 164 is reset.
The signal in the set-output 163 becomes zero, as a result of which the tran-sistor 161 becomes conductive, Through the electromagnet 152 passes a current Il, which gensrates a magnetic field which reinforces the magnetic field of the pormanent magnet 154. The output 167 of the monostable multivibrator remains zero, so that the transistor 160 keeps blocking. This situation is maintained9 until the signalpulse END is gsnerated (at the height of t2 in Figure 3) as a result of which a signal is produced in the set-output 163 of the flip-flop 164, by which the transistor 161 is bl ked. At the same time ' a signal is produced in the output of the monostable multivibrator 166, by which the transistor 160 is opened and a current I2 passes through the electro-magnet 152, which current generates a ma~netic field which acts against the magnetic field of the permanent ~agnet 154, so that the cover is opened. The output of the monostable multivibrator becomes zero after about 1 sec, as a resulS of which the sign~l in the output 167 of the monostabl~ multivibrator becomes zero and the transistor 160 is blocked. A new copying run can now be ., . . . .. ~
101~93~
started.
In the abovetescribed embodiment it is accepted that tho eloctro-maBnet and the permanont magnet are combined and are installed in tho frame.
This is a preferred embodiment, because in this way it is preventod, that electrical wires must be brought into the cover via the shaft 43. However, it is clear, that the invention is not limited to this embodiment, but that other combinations are possible. It is particularly possible in the embodi-ment represented to reverse the design, namely the electromagnet and the per-manent magnet in the cover, and the soft iron block in the frame 151. Other possible embodiments are a pormanent ~agnet in the cover, co~bined with an electromagnet provided with a soft iron core in the frame, and reversed, a permanent magnet in the cover, combined with an electromagnet provided with a magnetized core in the frame, and reversed, whereby the two permanent mag-nets attract each other, an electrom2gnet providcd with a soft iron core in the cover combined with an electromagnet provided with a magnetized core in the frame and reversed, and an electromagnet provided with a magnotized core in the cover, combined with an electromagnet provided with a magnetized core in the frame, whereby the two magnetized cores attract each other magnetically.
, . .
Such a device is known from United States patent specification 3,888,581 or 3,888,582.
In this known device the cover in unlatched at the end of a copying run by slightly lifting the cover by means of a cam, as a result of which an air gap is made between the permanent magnet and the cooperating soft iron mass. Consequently the magnetic attraction between these two elements de-creases considerably, so that the force of the lifting device is sufficient for further opening the cover.
The disadvantage of this known device is, that the unlatching takes place with the aid of moving parts which must transfer a relatively high force. Therefore these parts are liable to wear, which after frequent use of the cover may cause the unlatching mechanism not to work reliably.
According to the present invention, there is provided in a device for covering originals during copying thereof by exposure on a transparent plate mounted in a frame of a photoco W ing apparatus, including a cover for pressing an original against said plate, means supporting said cover for swinging movement to and away from a closed position over said plate, means constantly exerting a force biasing said cover away from said plate, and disengageable means on said cover and said plate for ]atching said cover in closed position against the force of said biasing means, the improvement consisting in: said latching means comprising on one of said cover and said frame a permanently magnetic body, on the other of them a magnetically attractable body that confronts said magnetic body when said cover is in closed position and on either said cover or said frame an electromagnet the core of which is constituted by one of said bodies, said permanently magnetic body in the closed position of said cover attracting said attractable body -1- ~
B
:~Of~9~3~;
with a force exceeding the force of said biasing means, and means for generat-ing in said electromagnet an electromagnetic field counteracting the magnetic field of said magnetic body with a force sufficiently strong that the com-bined forces of said fields on said attractable body are exceeded by the force of said biasing means so that said biasing means will itself lift said cover away from said plate.
Thus, the magnetic force of attraction of the permanent magnet is reduced without the use of moving parts in such a way, that the cover can be lifted by the lifting device.
In a preferred embodiment a magnetic field is generated in the electromagnet during the copying run, which magnetic field has a polarity being equal to the polarity of the magnetic field of the permanent magnet.
Thereby the magnetic attraction can be increased so much, that it is very difficult to open the cover by hand, in which way the cover is pre-vented from being opened during the copying. In this way, when thicker objects, such as books, must be pressed against the glass plate, the magnetic force of attrac~ion is sufficient to guarantee an effective contact. This cannot happen by increasing the magnetic field strength of the permanent magnet, as it must still be possible to open the cover by hand before the beginning of the copying run.
Other characteristics and advantages of the invention will become clear from the following description whereby reference is made to the enclosed drawings, in which:
Figure 1 is a schematic section of a cover in which the locking mechanism according to the invention is applied.
Figure 2 is an electric scheme wherein the operation of the locking mechanism according to the invention can be controlled, and Figure 3 is a schematic time diagram of the signals which play a part in the scheme of Figure 2.
In Figure 1 a cover 2, cooperating with a glass plate 1, is schem-atically represented in section, as described in more details in the U.S.
patent No. 4,035,077 of applicant. The cover 2 can hinge round a shaft, in ~069366 order that it can be moved towards and away from the glass plate 1, whereby the shaft 43 is installed near a longitudinal edge 30 of the cover 2. As ; described in above-mentioned U.S. patent No. 4,035,077 a spring is installed on the shaft 43, which spring tries to turn the cover 2 away from the gLass plate.
Near the opposite longitudinal edge 25 of the cover 2 a block 150 of magnetizable material, for instance a soft iron core, is fixed against and in the lower side of this edge. In the frame 151 of the copying device on which the cover 2 is installed, an electromagnet 152 is fixed at a place which in the closed position of the cover, lies opposite to the block 150.
This electromagnet 152 consists of an electromagnetic coil 153 and a core 154 which in the embodiment represented consists of a permanent magnet.
The operation of the latching mechanism is as follows. In the closed position of the cover 2, the magnetic attraction between the permanent magnet 154 and the soft iron block 150 is sufficient to keep the cover in the closed position against the force of the spring acting on the shaft 43. In case sheetlike or thin originals lie on the glass plate, this magnetic force of attraction is also sufficient to keep these in good contact with the glass plate. As soon as the copying run is finished, a magnetic field is generated via the electromagnet 152, which magnetic field acts against the magnetic field of the permanent magnet. This counter-acting magnetic field has in any case been designed to be so strong that magnetic force of attraction between the block 150 and the permanent magnet 154 becomes weaker than the upward force which is exercised via the spring on the shaft 43, so that the cover turns upwards. As soon as the air gap between the block 150 and the permanent magnet has become great enough, the excitation of the electromagnet 152 can be stopped, as the magnetic attraction between block 150 and magnet 154 has become negligibly low. The original can now be exchanged and the cover can be closed by hand, after which the following copying run can be started.
In the case of thicker originals the electromagnet 152 can also be used for generating an additional magnetic attraction of the cover 2, by generating a magnetic field via the electromagnet 152, which magnetic field ~0693~;6 reinforces the magnetic field of the permanent magnet 154. This extra magnetic field can for instance be generated when pressing the print knob for starting the copying run.
In Figure 2 a circuit is representecl with which the above-described operation can be realized. Hereby it is accepted, that when starting the copying run a signal pulse PRINT is generated, whereby these signal pulses can be derived from the control system of the copying device, as described in more detail in U.S. patent No. 3,912,390. Thereby the signal END will be generated immediately after the exposure device is excited for the last time.
:
~, ,~
, -3a-101~93~
The electromagnet 152 is connected on the one part with the positive clamp of a diroct current source of for instance ~12 V, and on the other part via a transistor 160 with a reference tension or earth and via a transistor 151 with the positive clamp of a direct voltage sou~ce of for instance ~24 V.
The base of the transistor 161 is connected via an amplifier 162 with ~he set-output 163 of an RS-flip-flop 164, of which the set-input is connected with the signal-emitter END and the reset-input is connected with the signal-emitter PRINT.
The base of the transistor 160 is connected via an amplifier 165 with the output 167 of a monostable multivibrator 166, of which the input is connected with the signal-emitter END. The monostable multivibrator 166 lengthens the signalpulse END to a pulse of about 1 sec.
The operation of this electrical scheme is now as follows ~compare Figure 3). When the copying run is started (at the height of tl), the signal pulse PRINT is generated, as a resul~ of which the flip-flop 164 is reset.
The signal in the set-output 163 becomes zero, as a result of which the tran-sistor 161 becomes conductive, Through the electromagnet 152 passes a current Il, which gensrates a magnetic field which reinforces the magnetic field of the pormanent magnet 154. The output 167 of the monostable multivibrator remains zero, so that the transistor 160 keeps blocking. This situation is maintained9 until the signalpulse END is gsnerated (at the height of t2 in Figure 3) as a result of which a signal is produced in the set-output 163 of the flip-flop 164, by which the transistor 161 is bl ked. At the same time ' a signal is produced in the output of the monostable multivibrator 166, by which the transistor 160 is opened and a current I2 passes through the electro-magnet 152, which current generates a ma~netic field which acts against the magnetic field of the permanent ~agnet 154, so that the cover is opened. The output of the monostable multivibrator becomes zero after about 1 sec, as a resulS of which the sign~l in the output 167 of the monostabl~ multivibrator becomes zero and the transistor 160 is blocked. A new copying run can now be ., . . . .. ~
101~93~
started.
In the abovetescribed embodiment it is accepted that tho eloctro-maBnet and the permanont magnet are combined and are installed in tho frame.
This is a preferred embodiment, because in this way it is preventod, that electrical wires must be brought into the cover via the shaft 43. However, it is clear, that the invention is not limited to this embodiment, but that other combinations are possible. It is particularly possible in the embodi-ment represented to reverse the design, namely the electromagnet and the per-manent magnet in the cover, and the soft iron block in the frame 151. Other possible embodiments are a pormanent ~agnet in the cover, co~bined with an electromagnet provided with a soft iron core in the frame, and reversed, a permanent magnet in the cover, combined with an electromagnet provided with a magnetized core in the frame, and reversed, whereby the two permanent mag-nets attract each other, an electrom2gnet providcd with a soft iron core in the cover combined with an electromagnet provided with a magnetized core in the frame and reversed, and an electromagnet provided with a magnotized core in the cover, combined with an electromagnet provided with a magnetized core in the frame, whereby the two magnetized cores attract each other magnetically.
, . .
Claims (7)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In a device for covering originals during copying thereof by exposure on a transparent plate mounted in a frame of a photocopying apparatus, including a cover for pressing an original against said plate, means supporting said cover for swinging movement to and away from a closed position over said plate, means constantly exerting a force biasing said cover away from said plate, and disengageable means on said cover and said plate for latching said cover in closed position against the force of said biasing means, the improvement consisting in: said latching means compris-ing on one of said cover and said frame a permanently magnetic body, on the other of them a magnetically attractable body that confronts said magnetic body when said cover is in closed position and on either said cover or said frame an electromagnet the core of which is constituted by one of said bodies, said permanently magnetic body in the closed position of said cover attract-ing said attractable body with a force exceeding the force of said biasing means, and means for generating in said electromagnet an electromagnetic field counteracting the magnetic field of said magnetic body with a force sufficiently strong that the combined forces of said fields on said attract-able body are exceeded by the force of said biasing means so that said biasing means will itself lift said cover away from said plate.
2. A device according to claim 1, and further comprising means for generating in said electromagnet a reversed electromagnetic field reinforc-ing the magnetic field of said magnetic body during a copying run of an original being pressed by said cover against said transparent plate.
3. A device according to claim 1, said magnetic body forming the core of said electromagnet.
4. A device according to claim 1, said magnetic body and said electro-magnet being mounted in said frame at a location bordering said transparent plate, said magnetic body forming the core of said electromagnet, and said magnetically attractable body being a block of soft iron fixed to said cover at a location lying opposite to said core when said cover is in closed position.
5. A device according to claim 1, said field generating means includ-ing circuit means for passing a direct current through the coil of said electromagnet in a direction to produce an electromagnetic field having a polarity opposite to that of the magnetic field of said magnetic body, and means for activating said circuit means at the end of a copying run of an original being pressed by said cover against said transparent plate.
6. A device according to claim 2, said field generating means includ-ing first circuit means for passing a direct current through the coil of said electromagnet in a direction to produce an electromagnetic field having a polarity corresponding to that of the magnetic field of said magnetic body, second circuit means for passing a direct current through said coil in the opposite direction to produce an electromagnetic field having a polarity opposite to that of said magnetic field, means for activating said first circuit means at the start of a said copying run, and means for inactivating said first circuit means and activating said second circuit means at the end of the copying run.
7. A device according to claim 1, and further comprising means for generating in said electromagnet a reversed electromagnetic field reinforc-ing the magnetic field of said permanently magnetic body during a copying run of an original being pressed by said cover against said transparent plate, said field generating means including first circuit means for passing a direct current through the coil of said electromagnet in a direction to produce an electromagnetic field having a polarity corresponding to that of the magnetic field of said magnetic body, second circuit means for passing a direct current through said coil in the opposite direction to that of said magnetic field, means for activating said first circuit means at the start of a said copying run, and means for inactivating said first circuit means and activating said second circuit means at the end of the copying run, said electromagnet and said magnetic body being mounted in said frame at a location bordering said transparent plate, said magnetic body forming the core of said electromagnet, and said magnetically attractable body being a block of soft iron fixed to said core at a location lying opposite to said core when said cover is in closed position.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL7514623A NL7514623A (en) | 1975-12-16 | 1975-12-16 | COPIER. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1069366A true CA1069366A (en) | 1980-01-08 |
Family
ID=19825032
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA267,821A Expired CA1069366A (en) | 1975-12-16 | 1976-12-14 | Copying device with electromagnetic cover release |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS5947293B2 (en) |
| CA (1) | CA1069366A (en) |
| CH (1) | CH610671A5 (en) |
| DE (1) | DE2651895C2 (en) |
| FR (1) | FR2335870A1 (en) |
| GB (1) | GB1537778A (en) |
| NL (1) | NL7514623A (en) |
| SE (1) | SE416002B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5745570A (en) * | 1980-09-03 | 1982-03-15 | Ricoh Co Ltd | Press-contacting device for original |
| JPH01259771A (en) * | 1988-04-08 | 1989-10-17 | Japan Atom Energy Res Inst | Damping means for fly-wheel generator |
| JPH0453258U (en) * | 1990-09-12 | 1992-05-07 |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB374219A (en) * | 1931-04-29 | 1932-06-09 | William Booth | Improvements relating to photographic printing boxes |
| DE806628C (en) * | 1948-10-02 | 1951-06-14 | Rudolf Magnus | Electromagnetically operated copy cover lock |
| US3888582A (en) * | 1974-03-08 | 1975-06-10 | Xerox Corp | Semi-automatic document handler |
| NL171933C (en) * | 1975-03-03 | 1983-06-01 | Oce Van Der Grinten Nv | COPIER. |
-
1975
- 1975-12-16 NL NL7514623A patent/NL7514623A/en active Search and Examination
-
1976
- 1976-11-02 CH CH1378676A patent/CH610671A5/en not_active IP Right Cessation
- 1976-11-05 JP JP13367976A patent/JPS5947293B2/en not_active Expired
- 1976-11-13 DE DE19762651895 patent/DE2651895C2/en not_active Expired
- 1976-11-17 GB GB4792876A patent/GB1537778A/en not_active Expired
- 1976-12-14 CA CA267,821A patent/CA1069366A/en not_active Expired
- 1976-12-14 FR FR7637629A patent/FR2335870A1/en active Granted
- 1976-12-14 SE SE7614069A patent/SE416002B/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| DE2651895C2 (en) | 1985-02-28 |
| FR2335870B1 (en) | 1980-10-03 |
| NL7514623A (en) | 1977-06-20 |
| GB1537778A (en) | 1979-01-04 |
| JPS5276028A (en) | 1977-06-25 |
| JPS5947293B2 (en) | 1984-11-17 |
| SE416002B (en) | 1980-11-17 |
| FR2335870A1 (en) | 1977-07-15 |
| CH610671A5 (en) | 1979-04-30 |
| SE7614069L (en) | 1977-06-17 |
| DE2651895A1 (en) | 1977-06-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |