EP0184614A1 - Device for feeding sheets to a printer - Google Patents

Abstract

The device on a printer for the single feeding of forms or tickets via a paper guide channel to the platen roller is characterized in that at least one sensor (S1, S2) is arranged in the area of the paper guide, which uses the inputs of a sequence control that processes the electrical states of the sensors is connected and the outputs (LF and ONLINE) of this signal processing circuit are connected to inputs of the printer's own function inputs (SEL) and (LF). With this device, a commercially available printer can be converted into a log printer for existing forms or tickets without modification.

Description

The invention is in the field of control of small printers and relates to a device for the single feeding of forms or tickets, according to the preamble of claim 1 and the use of the device as a log printer.

More and more measuring devices are microprocessor or computer controlled in the course of general technical development. On the one hand, this increases the need for logging the measurement results. On the other hand, the requirements for the quality of the logging and also for the amount of data to be logged have increased significantly.

Widespread as a protocol printer, for example in clinical analysis, form or so-called ticket printers. These are specially designed printers, which are often only intended for a specific application, and are usually built around the ticket to be used. At least the dimensions of the ticket guide mechanism, the platen and not infrequently the outside dimensions of the entire printer are tailored to the ticket. Any change in the ticket format in the course of further development also requires drastic changes to the log printer itself, up to a completely new design.

Such changes in the format of a ticket are, however, imperative at the latest when more extensive additional information is to be printed out or when one decides to expand the measuring device functionally.

In the course of this general technical development, it was increasingly required that the log printers should also be capable of graphics, i.e. that digital measurement results should be printed out in the form of graphical representations.

The majority of the protocol printers are the matrix printers, which meet the most varied requirements with reasonable effort. So-called typewriter printers, which are generally more elaborate than matrix printers, are occasionally also used as log printers. These printers are able to output the resulting logs in typewriter quality.

On the other hand, the same type of printer as universal printer has found wide acceptance both in the area of administration and in the technical area. The control of such generally usable matrix as well as beautiful printers is carried out by control commands, some of which must be received together with the data to be printed out via the data lines (software-controlled) and some must be given via separate control lines (hardware-controlled). Individual commands, such as the start command and a possible print interruption, can usually also be entered manually using special function keys. The paper can also generally be pulled in by hand using the existing function keys. However, controlled devices for automatic paper feeding are also used. The line feed LF (line feed) and the select switch SEL play a special role in the function control of the printer. The line feed LF takes care of the paper feed by an amount to be precisely defined in advance (a so-called line) and at the end of printing for Ejection of the print medium. The SEL function opens or closes the data channel from the data source to the printer.

It is an object of the present invention to provide a log printer which can be converted from a general-purpose universal printer to a printer which can also be used as a form or ticket printer with as little additional effort as possible, without serious intervention in the original universal printer, be it in its electronic or in its mechanical parts. As a form or ticket printer, he should not only be able to automatically feed the form, but also to take special form requirements into account, which require precise alignment to the form set. Otherwise, the printer should remain usable as a universal printer according to its original function.

This object is achieved by the invention defined in the patent claims.

The solution to the problem according to the invention has the decisive advantage that existing or required universal printers can also be used as a log printer using predetermined forms or tickets by one-time adjustment. The adjustment is not serious and can be made without changes to the printer or its control. The adaptation is preferably carried out exclusively to elements or connections of the printer that are in any case accessible from the outside. As a result, the adjustment is not restricted to a specific printer category or to specific brands. Rather, practically all commercially available matrix, fine-writing or ink-jet printers can be adapted in the manner according to the invention. Likewise, the adaptation is independent of the type of printer interface, that is to say regardless of whether a parallel or a serial interface is used between the printer and the data source becomes. A printer adapted in this way can be used as a full ticket printer, for example in the field of clinical analysis. He is able to respond to certain form-related control characters which are attached to the ticket, for example in the form of markings and which preferably relate to the exact positioning of the ticket in the vertical direction and possibly also in the horizontal direction. In this way, excellent print quality can be achieved without any shifts in relation to given fields on the form, which are not only unsightly, but could lead to serious consequences, especially in medical technology, and must therefore be avoided under all circumstances.

The invention is explained in more detail below with the aid of the preferred embodiments and the drawings.

• Fig. 1 in perspektivischer Darstellung die Ticketeinzugvorrichtung mit Teilen eines damit ausgestatteten Universaldruckers,
• Fig. 2 in funktioneller Darstellung ein Ticket im oberen Bereich einer Ticketeinschubvorrichtung,
• Fig. 3 die Darstellung des Tickets im mittleren Bereich der Ticketeinschubvorrichtung gemäss Fig. 2,
• Fig. 4 die Darstellung des Tickets im unteren Bereich der Ticketeinschubvorrichtung gemäss Fig. 2,
• Fig. 5 das Blockschaltbild eines ersten Beispiels für eine elektronischen Auswerteschaltung,
• Fig. 6 den Signalverlauf an der Auswerteschaltung gemäss Fig. 5,
• Fig. 7 den Signalverlauf an der Schaltung nach Fig. 5 unter anderen Voraussetzungen,
• Fig. 8 ein vereinfachtes Ausführungsbeispiel einer Auswerteschaltung und
• Fig. 9 den Signalverlauf an der Schaltung nach Fig. 8.

Show it:

• 1 is a perspective view of the ticket collection device with parts of a universal printer equipped with it,
• 2 is a functional representation of a ticket in the upper area of a ticket insertion device,
• 3 shows the representation of the ticket in the central area of the ticket insertion device according to FIG. 2,
• 4 shows the representation of the ticket in the lower area of the ticket insertion device according to FIG. 2,
• 5 shows the block diagram of a first example of an electronic evaluation circuit,
• 6 shows the signal curve at the evaluation circuit according to FIG. 5,
• 7 shows the signal curve on the circuit according to FIG. 5 under different conditions,
• 8 shows a simplified exemplary embodiment of an evaluation circuit and
• 9 shows the signal curve on the circuit according to FIG. 8.

As already mentioned in the introduction, the device described in more detail below makes general use of the general control options for commercially available matrix, fine writing and inkjet printers, in particular the options for controlling such printers via separately accessible, e.g. on control buttons or on control signal connections to external control functions such as "SELECT" (SEL) or "LINE FEED" (LF).

Sensors, e.g. light barriers, which respond to corresponding features on the forms to be processed, include these control functions in an additional logical sequence control, so that the drawing and positioning of the form not only runs automatically, but is also individually controlled by the form being processed . Due to the additionally provided sequence control, no intervention is made in the electronics of the printer. The printer is practically controlled by the form itself, preferably according to the following procedure: pulling in the form / feeding the form / triggering the printing process / ending the printing process / ejecting the form. The processing described later takes over the processing of the features obtained from the form and the derivation of corresponding printer control signals. An advantageous further development contributes to the additional ease of use, according to which the sequential control blocks the printing process if the inserted form or ticket has been withdrawn from the ticket management for any reason. The control takes into account the usual equipment of a printer with a buffer memory. Several data records corresponding to the data for several forms can be read into such a memory. After a form has been printed and ejected, the control locks the SEL channel so that no data is written into space. The printer returns to the ready state and awaits the entry of the next form in order to print out the further data record.

Figure 1 now shows a schematic representation of the mechanical part of the device described as an example in connection with a commercially available printer. A form or ticket feeder 1 is attached by means of a mounting plate 5 over the platen 3 of the printer. Guide channels 2, 2 'corresponding to the ticket width and optionally displaceable in the direction of arrow B transversely to the form transport direction are designed as a feed slot for the ticket 8. An adequately shaped guide clip 4 holds the ticket 8, which is guided around the platen roller and is only partially shown in the figure, in the writing position. For the sake of clarity, the friction roller belonging to the printer and the print head are not shown. The latter is routed, as usual, over ticket 8 to be printed. The required writing width is controlled, for example, by the software used.

There are two sensors on the guide channels 2, 2 ', e.g. two light barriers S1 and S2 mounted, in relation to each other and in relation to the ticket 8 to be withdrawn in different vertical positions. These sensors provide the necessary information for the connected process control to achieve the desired ticket positioning. With the help of the mounting plate 5, the mechanical device for ticket management can also be easily retrofitted to or removed from an existing printer.

The ticket 8 drawn around the platen roller with the aid of the light barrier control is taken over again by the guide clip 4 when it exits the printer's own paper guide and brought into the printing position. It is advantageous if the prepositioned print head, which usually already has a paper guide plate, is also used as part of the entire ticket guide. With certain types of printer, the mechanical effort is considerably simplified.

In addition to minor mechanical adaptation measures on the printer, for example the cutting of threaded holes for mounting the device described, no further measures are required with regard to the mechanical device for connecting the conventional printer to the additional device described. The connection can also be made by any other detachable or permanent fastening means.

The function of the sensors, in this exemplary embodiment it is the light barriers S1 and S2, is shown schematically with reference to FIGS. 2, 3 and 4. In general, these figures show a guide channel 2 with the ticket 8 inserted therein, which is transported past the two light barriers S1 and S2 and between the platen roller 3 and friction wheel 6 to the print head 10. The guide 7 is the printer paper guide already mentioned. For fine adjustment of the desired ticket position, at least one of the light barriers, here the upper light barrier S1, can be moved in the direction of arrow A.

• 1.) S1 AUS / S2 AUS
• 2.) S1 EIN / S2 AUS
• 3.) S1 EIN / S2 EIN
• 4.) S1 AUS / S2 EIN

In rough approximation, this arrangement of light barriers offers the possibility of displaying four ticket positions in each direction of movement:

• 1.) S1 OFF / S2 OFF
• 2.) S1 ON / S2 OFF
• 3.) S1 ON / S2 ON
• 4.) S1 OFF / S2 ON

The combination of several of the basic states listed here occurs e.g. then when the ticket is pushed past the light barrier S1, but is pulled out of the paper guide again without reaching the light barrier S2. These conditions discussed above are used in this exemplary embodiment in a manner to be described in more detail later, using the sequence control for the printer control.

The functional sequence of the sequential control system and its interaction with the printer are described below.

Figure 2 shows the position of the ticket 8, in which it is pushed towards the light barrier S1. Since both sensors S1 and S2 have not yet responded, ticket position 1) is available, namely S1 (OFF) / S2 (OFF). This will keep the printer on standby. This means that the print head is e.g. in a position in which it forms part of the form or ticket management at the same time. The printer's paper feed is still standing still.

In the position shown in FIG. 3, ticket 8 has reached light barrier S1. The ticket position 2.) is recognized from the state of the two light barriers, namely state S1 (ON) / S2 (OFF). The device now registers that a ticket has been inserted and waits for it to be inserted or withdrawn again. If the latter is the case, the state S1 (ON-OFF) / S2 (OFF) has been provoked, which advantageously causes the printer to remain in the waiting state for the ticket to be printed.

If the ticket is pushed in further, the ticket position 3) results according to FIG. 4, namely S1 (ON) / S2 (ON), which is used, for example, to activate the printer control function line feed (LF) and thus the Put the writing and friction rollers into operation. The ticket is now actively drawn in until it reaches sensor position 4.), namely S1 (OFF) / S2 Has reached. This also means reaching its writing position, whereupon the printer's paper drive is stopped. The printer control function Select (SE) is addressed by the same criterion, whereby the data channel is opened so that the printout of the transmitted protocol data begins.

The desired printing position can be finely adjusted by moving the light barrier S1. For example, the bottom edge of the ticket triggers the printing process. The lower edge is the actual reference value for the field to be printed on the ticket. In the example, it forms a position or control feature to which the sensors S1, S2 respond. Instead of the lower edge of the ticket or in addition to it, according to a modified exemplary embodiment, other types of control features can be provided on the form, e.g. optically or magnetically readable lines, die cuts or similar marks. Coded characters, e.g. in the form of a bar code on the form, preferably on the edge thereof. The sensors must be adapted to the type of brand coding.

For fields to be printed on a form that are to be left blank for any reason in normal operation, tickets with a perforation can be used, in which a part can be separated before the special printout, the shorter ticket now allowing printing on the head area. It is also possible to use any specially designed tickets with marginal marks on the left and right or only on one side, with distance-coded marks, registration holes, etc. in connection with light barriers, but it is only intended to show how varied this basically simple measure according to the invention is to realize a very powerful log printer.

An example of the sequence control is described below with reference to FIG. 5, which processes the sensor signals D1, D2 from the sensors S1, S2 and derives suitable control signals for the printer 50 therefrom.

As already mentioned, the device makes use of only two switching functions available on most printers, both on matrix as well as on Schönschreib- or inkjet printers, namely Line-Feed LF and Select SEL, i.e. paper transport in the vertical direction with software-controllable stride length and data flow OPEN / CLOSE.

According to FIG. 5, the signal D1 from the first sensor S1 is supplied on the one hand to a clock-controlled logic module 20 and on the other hand to a second and a third logic module 25 or 26. The signal D2 of the second sensor S2 is both the third logic module 26 and also fed to a fourth logic module 27. The second, third and fourth logic modules 25, 26, 27 are also supplied with a ready signal ON-LINE-MONITOR coming from the data source of the printer 50. The output of the fourth logic module 27 is connected to a time module 21, which is controlled by clock signals T from a clock generator 28. The time module 21 can also be switched as a monoflop. The output C of the time module 21 leads to a fifth logic module 24, to which the outputs A, B of the second and third logic modules 25, 26 are also fed. At the output of the fifth logic module 24, the select signal SEL is applied to control the connected printer 50. The output of the first logic module 20 is at the LF control input of the printer 50.

Fig. 6 shows the corresponding signals as they occur on the circuit of Fig. 5 in normal operation. The cycle begins at the time T1, at which the ticket reaches the first sensor S1 and starts the feed motor (not shown) of the printer 50 via the line LF. The ticket is then transported beyond time T2, at which the ticket reaches the second sensor S2. At time T3, the ticket has reached the intended printing position. Now the SEL control line is activated to accept the print data. In accordance with the software control that is now active, LF signals (SWLF) appear in connection with the print program. After completion of the printing process at time T4 (DATA END), a longer, also software-controlled LF signal for ticket ejection is given (SWLF). After this transmission has ended, the signal C appears at time T5, which blocks the control input SEL again.

FIG. 7 shows the case in which a ticket was initially withdrawn, that is to say it passed the first sensor S1, but was then withdrawn again. The signal D2 coming from the second sensor S2 breaks off before T3, whereupon LF is interrupted prematurely and the ticket does not have to be brought into the printing position. The SEL signal is not activated.

8 shows a simplified exemplary embodiment with only one sensor S1. In this case, the sequential control system provides for direct passage of the signal D1 coming from the sensor SI to the control input LF of the printer 50 via an amplifier 30. At the same time, the control input SEL of the printer is activated via a logic block 31. Logic block 31 blocks the output (select) after a time determined in block 31 at T5 according to FIG. 9.

FIG. 9 shows the associated signal profiles, the functional sequence essentially corresponding to that from FIG. 6.

Optionally, a light emitting diode, e.g. Be switched ONLINE on the printer to display the general or a special operating status, e.g. whether the data channel is open or closed.

The example given here is designed for a commercially available matrix printer. Other printers need different timewindow values that can be easily tried out. In principle, this type of circuit structure is suitable for all common printers.

Special tickets are not required for the device described. Rather, existing, tried-and-tested forms or tickets can be used in an unchanged commercial printer without modification. The device described here, coordinating the printer and the ticket, enables a less complex conversion of a commercially available universal printer to a high-quality log printer for processing tickets and forms that have already been introduced and are in use.

Claims (9)

1. Device on a printer for the single feeding of forms or tickets to the platen roller, characterized in that at least one form guide (2, 2 ') leading to the platen roller (3) is provided that in the area of the form guide (2, 2') at least one position sensor (S1, S2) is arranged which responds to position features of the form or the ticket and which is connected to the inputs of a sequence control (Fig. 5, 8) processing the electrical states of the sensor and that control outputs this sequence control are led to control inputs (SEL, LF) of the printer (5c). 2. Device according to claim 1, characterized in that two sensors are provided and that the form edge entering the form guide serves as a position feature. 3. Device according to claim 2, characterized in that the distance of the two sensors (S1, S2) measured in the direction of travel of the form is connected to the distance of the first line to be printed on the form from its front edge. 4. The device according to claim 1, characterized in that the sensor or the sensors (S1, S2) are sensitive to features which are attached or applied to the forms. 5. The device according to claim 1, characterized in that optical sensors are provided. 6. The device according to claim 1, characterized in that character or bar code readers are provided as sensors (S1, S2). 7. The device according to claim 1, characterized in that the sensor or sensors (S1, S2) on the form guide (2, 2 ') is / are attached. 8. The device according to claim 1, with two sensors, characterized in that the sequence control (Fig. 5) with means (21) for time pulse-controlled interval measurement between the occurrence of the first measuring pulse coming from the first sensor (S1) and a second measuring pulse and that a time-controlled logic module (24) is provided for emitting a control signal (SEL) which is dependent on the measurement results previously obtained and which causes the print data to be transmitted to the printer (50). 9. Use of the device according to claim 1 as a log printer.

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