EP0249523B1 - Verfahren und Vorrichtung zum Betrieb eines Thermodruckkopfes - Google Patents

Verfahren und Vorrichtung zum Betrieb eines Thermodruckkopfes Download PDF

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Publication number
EP0249523B1
EP0249523B1 EP87401197A EP87401197A EP0249523B1 EP 0249523 B1 EP0249523 B1 EP 0249523B1 EP 87401197 A EP87401197 A EP 87401197A EP 87401197 A EP87401197 A EP 87401197A EP 0249523 B1 EP0249523 B1 EP 0249523B1
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EP
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Prior art keywords
heating
time
cycle
cycles
during
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EP87401197A
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English (en)
French (fr)
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EP0249523A1 (de
Inventor
Maurice Lacord
Christian Lavergne
Patrick Vegeais
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Sagem SA
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Sagem SA
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/315—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of heat to a heat sensitive printing or impression-transfer material
    • B41J2/32—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of heat to a heat sensitive printing or impression-transfer material using thermal heads
    • B41J2/35—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of heat to a heat sensitive printing or impression-transfer material using thermal heads providing current or voltage to the thermal head
    • B41J2/355—Control circuits for heating-element selection

Definitions

  • the present invention firstly relates to a method of controlling a print head, or writing, thermal, of the serial type, for a printing system, in particular for a printer connected to a word processing device. .
  • a thermal writing head generally comprises a plurality of heating elements, in general resistive elements arranged to be traversed by a current, and to cooperate either directly with a printing medium, heat-sensitive paper, or indirectly with a medium.
  • ordinary printing by means of a ribbon coated with an ink melting with the heat of the elements. In the first case, it is a direct thermal printing, in the second case, a thermal transfer printing.
  • the movable head comprises at least one bar, generally vertical, of elements, aligned in a direction orthogonal to the direction of rectilinear displacement, during the printing of a line of graphics, corresponding to the height of the bar, of a head support carriage.
  • Such a type of printing is like document DE-A-3315257.
  • the invention relates to a method for controlling a serial type thermal writing head for a printer, provided with a strip of heating elements, in which,
  • said longitudinal displacement head is driven along a line to be printed, at a determined speed
  • the heating elements being subjected to thermal cycles each comprising an initial heating time and a cooling time to print dots.
  • the set of heating elements which are heated during the same cycle obviously depends on the configuration of the transverse section of the line to be printed, of dimension L, equal to the product of the speed of displacement by the duration T of the cycles.
  • the vertical definition depends only on the size and the spacing of the heating elements of the writing head.
  • the horizontal definition is approximately inversely proportional to the drive speed of the head.
  • the thermal inertia of a heating element it is not possible to make the interval of time during which it is hot enough to print as small as desired. This time interval is therefore bounded by a lower limit, the horizontal dimension of the "point" that it prints is therefore substantially inversely proportional to the speed of drive of the head.
  • the present invention aims to provide a better compromise, that is to say, at constant writing speed, better horizontal definition or, with equivalent horizontal definition, greater writing speed.
  • the present invention relates to a method of the type defined above, characterized in that the duration of the cycles is chosen at most equal to the duration of printing of the dots and that some of the heating elements are subjected to heating for a period starting in the middle of the cycles.
  • the invention therefore provides for being able to subject it, within the same cycle, to a second heating.
  • the heating element When the heating element is subjected to two successive heatings during the same cycle, it prints an "extended point".
  • the start of this extended point coincides with the start of a normal point, but its length is greater than that of the normal point.
  • the invention provides that it can only be subjected to heating from the middle of the cycle.
  • the heating element prints an offset point.
  • the start of this offset point is offset by half the width of a slice with respect to a normal point.
  • the initial heating time and the heating time starting in the middle of the cycle are less than half the duration of a cycle.
  • the offset point has the same length as the normal point and the extended point a length substantially equal to one and a half times the length of the normal point.
  • the possible offset being equal to half a normal point length, we can say that we obtain a "pseudoresolution" double of the original resolution.
  • a true doubie resolution would indeed suppose that the length of the point is divided by two, which is not the case.
  • the duration (TI) of heating, during a first half-cycle, of a heating element determined is modulated so as to shorten this duration if this heating element has been heated during one of the two preceding half-cycles, and modulating the duration (TID) of heating, during a second half-cycle, of a determined heating element so as to shorten this duration if this heating element has been heated during one of the three preceding half-cycles.
  • the writing head is provided with a first bar and a second transverse bar arranged one after the other in the longitudinal direction, and in which, at during an odd-order cycle, the heating elements of the second strip are not subjected to any heating, and, during an even-order cycle, the heating elements of the first strip are not subjected to any heating .
  • a thermal print head 14 of serial type the head 14 is driven in longitudinal displacement , here horizontal, along the line to be printed 10, in the direction of the arrow 15, using a drive device which is not shown because it is conventional.
  • Line 10 is broken down into a series of transverse sections 10a, 10b, ..., 10m, ... whose horizontal dimension is equal to the horizontal dimension, or length, L of an elementary point 100 that each of the heating elements 140 when it heats.
  • the heating elements 140 are distributed along a transverse bar, here vertical, the height of which therefore corresponds to the height of the line 10.
  • each section 10m is printed during a writing cycle the duration T of which is equal to the length L of a point 100, divided by the drive speed of the head 14.
  • Each of the heating elements 140 is here a resistive element, accessible individually by connections not shown in FIG. 1, for the sake of simplicity. We will now describe the method of controlling one of these heating elements 140, the task of which is obviously to print a series of dots whose configuration depends on the line to be printed.
  • each writing cycle of duration T is divided into two half-cycles of duration T / 2. It is expected to be able to heat, at the start of each half-cycle, the heating element considered for a duration TI for each first half-cycle and for a duration TID for each second half-cycle.
  • the heating element is heated here by passing it through a current I so that, taking into account its thermal inertia, after heating for the duration TI or for the duration TID, its temperature 8 remains above a threshold temperature ⁇ s for a time equal to T.
  • the threshold temperature ⁇ s is that beyond which the paper is printed, the point printed by the heating element heated for a duration TI or TID corresponds to the length L.
  • the durations T1 and TID of the heating phases are modulated so as to shorten them if the heated element is still hot at the start of each of these phases.
  • the duration TI of heating during a first half-cycle takes the value T1 if the heating element has not been heated during any of the two half-cycles preceding this first half-cycle; otherwise, the duration TI takes the value T2, with:
  • the heating time TID during a second half-cycle takes the value T1 D if the heating element has not been heated during any of the three half-cycles preceding this second half-cycle; otherwise, the duration TID takes the value T2D, with:
  • FIG. 4 shows, by way of example, a certain number of configurations to be printed and the shape of the heating current 1.
  • FIG. 5 shows the result obtained in the case analogous to that of FIG. 3, of writing an uninterrupted series of normal points. It shows that the temperature remains below the maximum temperature ⁇ max.
  • the writing head 14 being provided with a plurality of heating elements 140 distributed on a vertical bar, at each first half-cycle of a cycle, a first set of points is heated which corresponds to the configuration of the first half-section of the section to be written corresponding to the cycle considered, and each second half-cycle, a second set which corresponds to the configuration of the second half-section.
  • the thermal stresses on the heating elements are quite severe, in particular when writing a continuous horizontal line where the temperature 8 must remain permanently greater than the write threshold ⁇ s .
  • the life of the heating elements, and therefore of the head is relatively short.
  • the first strip 141 is active during write cycles of odd order, while it is at rest during write cycles of even order.
  • the second strip 142 is active during write cycles of even order, and at rest during write cycles of odd order. That is to say that the first strip 141 prints only the odd-order sections, while the second strip 142 prints only the even-order sections.
  • the writing is only complete after the passage of the two bars.
  • the part common to the offset point and to the normal point does not present any difference in shade because all of the ink of the heat-sensitive paper, in the case of direct printing, or of the ribbon stationary relative to the paper, in the case of transfer printing, is released by the first heating element.
  • the device shown in FIG. 8 is used, which receives on a bus 161 the data to be printed in the form of a digital signal and which controls the resistive elements 140 of the head 14 , including here a single bar of J elements.
  • a clock 1 of known type delivers on three outputs three clock signals SYP, SYD and H.
  • a sequence generator 2 receives the three signals SYP, SYD and H on three binary inputs and two digital signals, via two buses 21 and 22, on two digital inputs. It delivers on four binary outputs four sequential signals T1, Tl D, T2 and T2D.
  • a decoder circuit 16 receives the coded data in digital form, via the bus 161, on a digital input, as well as the signal SYP on a binary input. It delivers two groups of J binary output signals on two buses 31 and 32 of the type parallel to J bits, that is to say each comprising J parallel conductors.
  • a delay circuit 3 receives the signal SYP on a binary input and is connected to buses 31 and 32.
  • the delay circuit 4 delivers three groups of J binary output signals on three buses 41, 42 and 43, of the type parallel to J bits.
  • a multiplexer 4 of known type, of which a digital control input is connected to the digital output of a counter 6 receives the signals from the three buses 41, 42 and 43, and delivers three binary output signals on three outputs 71, 72 and 73.
  • the counter 6 is a modulo J counter, of known type, whose clock input receives the signal H and whose reset input receives the output signal from a detector 5 of the rising edges of the sequential signals T1, T1 D, T2 and T2D, which it receives on four binary inputs.
  • the counter 6 delivers a signal D on its overflow output.
  • a circuit 7 for calculating the information to be printed is provided with three binary inputs connected to outputs 71, 72 and 73, and four binary inputs receiving the sequential signals T1, T1 D, T2 and T2D. It delivers, on two binary outputs, two INF and CE output signals.
  • a register 8 of the known type with serial input and parallel output at J bits, receives on a clock input, the signal H after passing through a logic gate 9 controlled by the signal D.
  • the J conductors of the parallel output of the register 8 are connected to a buffer register 10 with parallel input and output, controlled by the signal D after passing through a shaping circuit 11.
  • J conductors of the parallel output of register 10 are connected to J AND gates 12 of which the J other inputs receive the signal CE.
  • each AND gate 12 is connected to the control input of a controllable switch 13 disposed between a first terminal of a supply circuit 150 delivering the voltage VP and a terminal of one of the J resistive heating elements 140 the other terminal of which is connected to the second terminal of the supply circuit 150.
  • the supply circuit 150 also supplies electrical energy to all the elements of the preceding circuits, in a manner not shown for the sake of simplicity.
  • Clock 1 delivers the signals SYP and SYD represented in FIG. 9, that is to say pulse trains with a frequency of recurrence equal to 1rr and offset with respect to each other by T / 2 .
  • the signal H not shown, is a train of pulses like the signals SYP and SYD, but of much higher recurrence frequency.
  • the sequential signals T1, T1D, T2 and T2D have the appearance shown in FIG. 9.
  • the signals T1 and T1D are at the high level for equal durations offset by T / 2, like the signals T2 and T2D.
  • the duration of the sequence at the high level of the signal T2 is less than the duration of the sequence at the high level of the signal T1.
  • the T1 and T2 signals go high during each pulse of the SYP signal.
  • the T1 D and T2D signals go high during each pulse of the SYD signal.
  • the decoder circuit 16 develops, as a function of the data it receives on the bus 161, two groups of J binary signals which possibly change with each pulse of the signal SYP.
  • the J binary signals of the first group are:
  • the J binary signals of the second group are:
  • n j i and p j i represent two control bits of the heating element 14, of rank j, for printing the wafer of rank i, in accordance with the following code.
  • the J signals of type ni are transported by bus 31 and the J signals of type p j i are transported by bus 32.
  • the delay circuit 3 delays these signals to deliver the three groups of J signals of the type n i j -1 , n i j -2 , and p i j -1 on the three buses 41, 42 and 43, respectively.
  • the counter 6 After each rising edge of one of the sequential signals T1, T1D, T2 and T2D detected by the rising edge detector 5, the counter 6 is reset and controls, at the rate of the clock signal H the time multiplexing of the buses 41, 42 and 43 on binary outputs 71, 72 and 73.
  • the circuit 7 for calculating the information to be printed calculates a binary signal INF which is at the high level if the heating element of rank j is to be heated and at the low level otherwise, for each of the four time intervals T2, (T1-T2), T2D, (T2D-T1D) of the range of rows (i-1), so as to heat during time T1 or time T2, and during time T1 D or time T2D, depending , on the one hand, of the command for the range of rank (i-1 and on the other hand of the state passed during the range of rank (i-2) of this element, in accordance with the method described.
  • the J values of the signal INF calculated one after the other by the calculation circuit 7 are stored in the series-parallel register 8, after each rising edge of one of the sequential signals T1, T1 D, T2 and T2D, then transferred to the buffer register 10 which controls, via the AND gates 12, the heating of the heating elements 14.
  • the AND gates cannot be turned on if the CE signal is at the high level.
  • This signal CE is produced by the calculation circuit 7 to be at the low level when the signal T1 and the signal T1D are normally at the low level, so as to ensure, even in the event of a malfunction of the circuits placed upstream of the doors 12, for example if T1 or T1D remain at the high level at the end of the current half-cycle, periodic cooling of the heating elements to avoid destruction.
  • the current 1 which flows in each heating element 14 is here equal to the voltage VP divided by the value of the resistance of a heating element.
  • the constitution of the sequence generator is shown in FIG. 10.
  • Two registers 23 and 24 receive the digital signals present on the buses 21 and 22 which, as will be seen below, control the durations of the signals T1 and T1D of a part and T2 and T2D on the other hand.
  • the output of register 23 is applied to two gate circuits 25 controlled by the signals SYP and SYD.
  • the output of register 24 is applied to two gate circuits 25, controlled by the signals SYP and SYD.
  • Four counters 26, each provided with a clock input receiving the signal H and a parallel input receiving the output of one of the gates 25 deliver, on their four sign outputs, the signals T1, T1 D, T2 and T2D.
  • circuit 2 The operation of circuit 2 is as follows. Each counter 26 is mounted as a down-counter and its sign output is therefore positive, after having been loaded at the digital output value of the corresponding gate 25, only for a time which depends on this digital value.
  • the signals shown in FIG. 9 are therefore obtained, the digital signal on the bus 21 controlling the duration, equal, of the signals T1 and T1 D and the digital signal on the bus 22 controlling the duration, equal, of the signals T2 and T2D.
  • These durations can therefore be adjusted by the operator to adapt the device to the characteristics of the heating elements of the writing head, by modifying the digital signals applied to the buses 21 and 22.
  • the decoder circuit 16 includes a memory which contains the different bit sequences n) and p) corresponding to the different alphanumeric characters to be written, the print quality of which will obviously be better, taking into account the particular possibilities of the process of the invention. print an offset point and an extended point.
  • This memory is addressed by addressing circuits of known type, in response to the coded data received on the bus 161.
  • the decoder circuit is therefore of known type, within the reach of those skilled in the art and will not be described further.
  • the delay circuit 3 is shown in FIG. 11. It comprises on the one hand three buffer registers 34, 35 and 36 connected in cascade between the bus 31 and the bus 42 and on the other hand two buffer registers 37 and 38 connected in cascade between bus 32 and bus 43.
  • a shaping circuit 330 the input of which receives the signal SYP, delivers at the output a signal which controls, on the one hand, a circuit of doors 333 interposed upstream of the register 36, and on the other hand, and after passing through a delay line 331, two gate circuits 332 each interposed upstream of the registers 35 and 38.
  • the delay of the delay line 331 corresponds to the time necessary to transfer the data from one register like register 34 to the next like register 35, via a circuit of doors 332.
  • the bus 41 is connected in bypass to the output of register 35, upstream of door 333. The operation of a such a circuit is obvious to those skilled in the art.
  • the rising edge detector 5, as well as the circuit 7 for calculating the information to be printed, are entirely conventional combinational logic circuits, the design of which is within the reach of those skilled in the art, and will not be further described.
  • each of the bars is controlled by a device identical to that of FIG. 8, except that a single decoder 16, common to the two devices, is used .
  • the heating current of the resistive elements is constant and its duration of application variable.
  • the durations of the sequences at the high level of the signals T1 and T1D on the one hand, T2 and T2D on the other hand are equal. Furthermore, these durations are less than the duration T / 2 of a half-cycle.
  • the durations of the sequences at the high level of the signals T1, T1 D, T2 and T2D can be chosen as desired, while remaining less than the duration T of a cycle, in the cases where the head can withstand the resulting thermal stresses and where we do not seek to obtain points of constant length.
  • heating system by current flow in a resistive element can be replaced by any other heating system, for example by radiation, which may be suitable for thermal printing.

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Claims (10)

1. Verfahren zum Betrieb eines Reihetyp Thermoschreibkopfes (14) für ein Drucksystem, ausgestattet mit zumindest einem Quersteg von Heizelementen (140), in welchem:
der genannte Kopf in einer Längsverschiebung entlang einer Druckzeile (10) mit einer festgesetzten Geschwindigkeit mitgeführt wird,
die Heizelemente (140) Temperatur - Zeitfolgen unterworfen werden, wobei jede eine Anfangsheizdauer (TI) und eine Abkühldauer zum Drucken der Punkte umfaßt, dadurch gekennzeichnet,
daß die Dauer (T) der Zeitfolgen höchstens gleich der Druckdauer der Punkte gewählt wird,
und daß einige Heizelemente während einer in der Mitte der Zeitfolgenbeginnenden Zeitdauer (TID) einer Erwärmung unterworfen werden.
2. Verfahren nach Anspruch 1, in welchem, wenn ein Heizelement während einer Zeitdauer (TI) ungleich Null einer Anfangserwärmung unterworfen wird, dieses innerhalb derselben Zeitfolge einer zweiten Erwärmung unterworfen werden kann.
3. Verfahren nach einem der Ansprüche 1 und 2, in welchem, wenn innerhalb einer Zeitfolge die Anfangsheizdauer eines Heizelementes Null ist, dieses einer Erwärmung ausgehend nur von der Mitte der Zeitfolge unterworfen werden kann.
4. Verfahren nach einem der Ansprüche 1 bis 3, in welchem die Anfangsheizdauer (TI) und die in der Mitte der Zeitfolge beginnende Heizdauer (TID) geringer als die Hälfte der Dauer einer Zeitfolge sind.
5. Verfahren nach einem der Ansprüche 1 bis 4, in welchem während einer ersten Halbzeitfolge die Heizdauer (TI) eines festgesetzten Heizelements derart moduliert wird, daß diese Zeitdauer verkürzt wird, wenn dieses Heizelement während einer der beiden vorhergehenden Halbzeitfolgen erwärmt wurde, und während einer zweiten Halbzeitfolge die Heizdauer (TID) eines festgesetzten Heizelements derart moduliert wird, daß diese Zeitdauer verkürzt wird, wenn dieses Heizelement während einer der drei vorhergehenden Halbzeitfolgen erwärmt wurde.
6. Verfahren nach einem der Ansprüche 1 bis 5, in welchem der Schreibkopf (14') mit einem ersten Steg (141) und einem zweiten Steg (142) ausgestattet ist, welche einer nach dem anderen in Längsrichtung querliegend angeordnet sind, wobei die Elemente des zweiten Stegs (142) während einer Zeitfolge ungerader Ordnung und die Elemente des ersten Stegs (141) während einer Zeitfolge gerader Ordnung keiner Erwärmung unterworfen werden.
7. Vorrichtung zur Durchführung des Verfahrens nach einem der Ansprüche 1 bis 6 zum Betrieb eines Reihetyp Thermoschreibkopfes (14) für eine Druckeinheit, ausgestattet mit zumindest einem Quersteg von Heizelementen (140), umfassend:
Einrichtungen zur Führung des genannten Kopfes (14) in einer Längsverschiebung entlang einer Druckzeile (10) mit einer festgesetzten Geschwindigkeit,
Heizeinrichtungen (8-13) der genannten Heizelemente,
Recheneinrichtungen (1-7, 16) der Heizdauer, welche die genannten Heizeinrichtungen (8-13) steuern, um die genannten Heizelemente (140) Temperatur-Zeitfolgen zu unterwerfen, wobei jede eine Anfangsheizdauer (TI) und eine Abkühldauer zum Drucken der Punkte umfaßt, dadurch gekennzeichnet, daß
die Recheneinrichtung (1-7, 16) Einrichtungen (1) zur Einstellung der Dauer der Zeitfolgen auf eine Zeitdauer höchstens gleich der Druckdauer der Punkte, Einrichtungen (16) zur Bestimmung einiger Heizelemente, die einer Erwärmung ausgesetzt sein müssen, ausgehend von der Mitte der Zeitfolgen umfassen, und wobei diese zur Steuerung der genannten Heizeinrichtungen (8-13) derart angeordnet sind, um die genannten bestimmten Heizelemente während einer Zeitdauer (TID) beginnend in der Mitte der Zeitfolgen einer Erwärmung auszusetzen.
8. Vorrichtung nach Anspruch 7, in welcher die Recheneinrichtungen (1-7, 16) Einrichtungen (7) zur Modulation der Heizdauer (TI) eines festegesetzten Heizelements während einer ersten Halbzeitfolge derart umfassen, daß diese Zeitdauer verkürzt ist, wenn dieses Heizelement während einer der beiden vorhergehenden Halbzeitfolgen erwärmt wurde, und während einer zweiten Halbzeitfolge die Heizdauer (TID) eines festgesetzten Heizelements derart moduliert ist, daß diese Zeitdauer verkürzt ist, wenn dieses Heizelement während einer der drei vorhergehenden Halbzeitfolgen erwärmt wurde.
9. Vorrichtung nach einem der Ansprüche 7 und 8, in welcher die Recheneinrichtungen (1-7, 16) der Heizdauer
einen Zeitgeber (1) der Periode (T), welche höchstens gleich der Druckdauer der Punkte ist,
einen durch den genannten Zeitgeber (1) ausgelösten Sequenzgenerator (2), um zumindest ein Seriensignal (T1, T2) auf einem hohen Pegel während der Anfangsheizdauer und zumindest ein Seriensignal (T1 D, T2D) auf einem hohen Pegel während der Heizdauer ausgehend von der Mitte der Zeitfolgen zu erzeugen,
einen Decodierer (16) zur Festsetzung einerseits der Heizelemente, die einer Anfangserwärmung unterworfen sein müssen und andererseits, der Heizelemente einer Erwärmung ausgehend von der Mitte der Zeitfolgen unterworfen sein müssen,
einen Lofik-Schaltkreis (7) welcher mit dem aenannten Sequenzqenerator (2) und dem genannten Decodierer (16) verbunden ist, um die genannten Heizeinrichtungen (8-13) zu steuern, umfassen.
10. Vorrichtung nach Anspruch 9, in welcher
der Sequenzgenerator (2) zumindest zwei Seriensignale (T1, T2) auf einem hohen Pegel während der Anfangsheizdauer, und zumindest zwei Seriensignale (T1 D, T2D) auf einem hohen Pegel während der Heizdauer ausgehend von der Mitte der Zeitfolgen erzeugt,
ein Verzögerungsschaltkreis (3) an mehreren Ausgängen zwischen dem genannten Decodierer (16) und dem genannten Logik-Schaltkreis (7) geschaltet ist,
der genannte Logik-Schaltkreis (7) mit den genannten Ausgängen des genannten Verzögerungsschaltkreises (3) verbunden ist und zur Modulation der Heizdauer (TI) eines festgesetzten Heizelements während einer ersten Halbzeitfolge derart angeordnet ist, daß diese Zeitdauer verkürzt ist, wenn dieses Heizelement während: einer der beiden vorhergehenden Halbzeitfolgen erwärmt wurde, und während einer zweiten Halbzeitfolge die Heizdauer (TID) eines festgesetzten Heizelements derart moduliert wird, daß diese Zeitdauer verkürzt ist, wenn dieses Heizelement während einer der drei vorhergehenden Halbzeitfolgen erwärmt wurde.
EP87401197A 1986-06-05 1987-05-27 Verfahren und Vorrichtung zum Betrieb eines Thermodruckkopfes Expired - Lifetime EP0249523B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8608125A FR2599672A1 (fr) 1986-06-05 1986-06-05 Procede et dispositif de commande de tete d'impression thermique
FR8608125 1986-06-05

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EP0249523A1 EP0249523A1 (de) 1987-12-16
EP0249523B1 true EP0249523B1 (de) 1990-08-01

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US (1) US4789870A (de)
EP (1) EP0249523B1 (de)
DE (1) DE3764031D1 (de)
ES (1) ES2017733B3 (de)
FR (1) FR2599672A1 (de)

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ES2017733B3 (es) 1991-03-01
US4789870A (en) 1988-12-06
EP0249523A1 (de) 1987-12-16
FR2599672A1 (fr) 1987-12-11
DE3764031D1 (de) 1990-09-06

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