DE10332225A1 - Measurement and monitoring of ink used in an inkjet printer, whereby measurements of ink used during printing and or cleaning are corrected, using temperature and pressure measurements, to standard values - Google Patents

Abstract

Method for calculating and monitoring the instantaneous amount of ink in an ink reservoir (2), whereby the ink (2a) is containing in a fine capillary foam within the reservoir. Amounts of ink used during printing and or cleaning of the inkjet print head are calculated in the printer control unit using corrections for measured temperature and other physical parameters variations in the print head. The resultant converted ink usage values are continuously stored in a control unit memory. An independent claim is made for an arrangement for determining and monitoring the instantaneous ink usage in an inkjet printer.

Description

The The invention relates to a method and a device for determining and monitoring the current amount of ink liquid in an ink reservoir an ink printer, wherein the ink liquid under changing Temperature and viscosity from the ink reservoir, which is filled with fine capillary foam, via a fluid connection in a jet print head guided and in the form of drops for printing characters, pictures u. Like. Outcast and in which readings into an electronic memory chip which processes the printer control.

It is known that replaceable ink reservoirs in an ink printer can be provided with nonvolatile read / write electronic memories ( EP 0 433 280 B1 ), which contain information about the type, amount, color and age of the ink. This can be timely given via the printer control notes to the user to change the ink reservoir before the next print job can not be completed. However, it is not enough to provide only the status data of the printing medium, means for detecting a current filling state of the ink reservoir, means for detecting the storage amount of the electronic memory device corresponding to a minimum amount of the print medium, and triggering a warning signal and / or blocking the printing operation, if not high Measures the current fill state can be measured accurately enough and if certain physical variables are completely disregarded.

A even greater complication when measuring the filling condition occurs when the ink reservoir with fine capillary foam filled is and in addition to the pure ink also at intervals waste ink from the top into the ink reservoir is drained. The waste ink then sinks with a time delay the fine capillary foam and is later again as pure ink for Print available.

Of the Invention is based on the object when operating the printer even in harsher surroundings of factories and warehouses with a wide span of ambient temperatures involving at irregular intervals in the ink reservoir introduced Waste ink passing through the fine capillary foam and / or a cleaning station is cleaned, a more accurate determination of the current amount of ink liquid achieve.

The Asked object is inventively achieved in that consumed by printing and / or cleaning the nozzle print head Quantities of ink fluid by at least in the area of the ink reservoir and / or the nozzle head measured Temperature and other physical parameters in the printer control converted to a standard value and an ink quantity assigned to it calculated in the printer controller and stored continuously. As a result, the current residual ink quantity can be determined more accurately. Measurement errors that occur at different temperatures during the Ink consumption through printing and printhead cleaning and printing Postflow in the foam arise are taken into account. Likewise, the Increase in the volume of the nozzle head shot with ink droplets considering increasing temperature. So far that has been for the To save ink consumption for safety's sake, only the drop volume for the unfavorable Case valued, so the user exchanges in most cases (normal Operating temperature) the ink reservoir well before complete emptying out. However, this handling is neither economical establish still for reasons the environmental protection makes sense. This consideration also applies in similar Form for the cleaning process, because the amount of sucked ink also depends on the temperature.

at an ink reservoir, which contains a fine capillary foam for ink storage lies a large Area of different sized capillaries in front. In the printing operation are first especially the larger capillaries emptied, as they show the lower capillary pressure. With stronger emptying of the ink fluid supply are becoming more and more even the fine capillaries are emptied. The measure in which the foam ink can be taken, is determined by the temperature-dependent viscosity of the ink liquid also temperature dependent, especially if the ink supplies in the narrower capillaries a greater importance win.

Next the temperature plays the speed of the ink liquid withdrawal (by printing or printing nozzle cleaning) for the Amount of up to a given maximum vacuum during suction removable amount of ink a role. The reason is the limited Nachfließgeschwindigkeit the ink liquid in the foam towards the removal area.

Another factor influencing the ink liquid supply currently available for printing and cleaning, in the case of ink return, is the time between the initiation of the suction in the ink reservoir zurückge led ink and the time of the ink requirement. Since the cleaned (or unpurified) ink is returned to the upper portion of the ink reservoir, it takes some time for this ink to migrate to the extractable area. The ink is not yet available in front of this area. For better utilization of such ink liquid portions, the time influence on the amount of the existing ink must be taken into account.

A Embodiment of the invention is that for printing or cleaning consumed ink in different storage locations the electronic memory are stored in the printer control. It can the amounts of ink consumed by printing and cleaning in appropriate size units get saved.

To Other features provide that in a memory location a the ink fluid supply according set standard temperature is stored, wherein Furthermore Parameters are stored, indicating the temperature dependence of the ink supply describe removable ink volume. As a parameter comes, for example. a proportionality factor at approximate linear dependence or a proportionality factor and additionally Exponent or the coefficients for an nth-order polynomial when approaching through a nonlinear relationship or it can be a table be deposited, the temperature dependence of this amount of ink sufficiently accurately characterized. Here, the printer control can either the correction factor from the closest to the measured temperature Take a table value or it can be a more precise one by interpolation Determine value between two table values.

To further steps it is suggested that this is for one type of ink characteristic drop volumes at least in one storage location of the electronic memory module is deposited. Similarly, for the ink type characteristic parameters for the temperature dependence the drop volume in a similar manner as in the removal volume get saved.

When other sizes will be a correction factor and associated Parameter describing the temperature dependence of the ink liquid flow stored during suction from the ink supply.

A Another embodiment is that for the description of the Nachfließeigenschaften the ink liquid in the fine capillary foam a time constant and associated parameters at least stored in the electronic memory module and their temperature dependence be calculated in the printer controller.

To other features is based on a full ink reservoir. It is provided that a correction factor for the full Ink reservoir contained maximum withdrawal ink quantity by reading the current Operating temperature in the electronic memory of the printer control calculated based on the stored parameters. The printer controller Reads the current operating temperature from a temperature sensor one. Based on the on the electronic memory chip therefor stored parameters, the correction factor is calculated. hereby is taken into account, that the fine capillary foam, which serves as an ink reservoir, depending on the temperature taken a different total amount of ink can be. From this so determined temperature-dependent maximum ink removal amount and stored on the electronic memory module of the ink reservoir previous temperature and time-dependent determined consumption can the currently available Standing waste ink quantity can be calculated.

A Improvement of the invention is given by the fact that when printing ink drops counted by electronic pulses in the printer controller, by measuring the operating temperature in the area of the nozzle pressure head compared with a stored drop volume at standard temperature and thereby the current drop volume is determined. The multiplication the number of dropped ink drops with the volume of an ink drop gives the total consumed during the printing process or print job Amount of ink. As a result receives a realistic volume of used ink. Together with the temperature-dependent determined total removal amount of the ink supply results in the to the current operating temperature associated residual removal quantity Ink liquid. The printer control can detect whether for further printing activities yet enough ink liquid is available.

A further development provides that, depending on the negative pressure and a suction time, on the viscosity and on the properties of the fine-capillary foam and the stored parameters, the amount of cleaning ink is determined. When cleaning the nozzle print head ink is sucked through the pressure nozzles in the cleaning device. This removes dirt particles and possibly existing air bubbles. The amount of ink used for this purpose depends on the one hand on the negative pressure and the duration of the suction, which is determined by the printer control, on the other hand on the properties of the ink liquid (eg., The viscosity, the Temperaturabhän viscosity and the like. Like.) And the properties of the foam in the ink reservoir. The printer controller considers a volume of ink liquid typical of the cleaning process caused by it as spent ink. In addition, the correction factor stored on the electronic memory module and its temperature dependence are also taken into account. From this, the printer controller calculates the ink consumed in each cleaning operation. When using other types of ink in an ink reservoir in the same printer, using a different foam in the ink reservoir, with a different design of the ink reservoir or at other temperatures in the printer, the printer controller calculates a much closer to the absolute ink consumption when cleaning the nozzle head than at fixed, solely by the printer control predetermined values. Consumption by aspiration for cleaning can be added to the total, stored on the memory module ink consumption or stored separately for other uses on the memory module.

A even more precise determination of the amount of residual ink can be supported by that the printer control due at least in the electronic Memory module stored a rating of the total existing. Performing ink quantities, such that a time constant is taken into account, at least the type of ink reservoir, the capillary properties of the foam and the flow properties the ink liquid includes. For intensive printing (covering and large-area printing at high printing speed) quickly becomes the foam in the ink reservoir taken a high amount of ink. The removal area of the foam depleted of ink, since these, especially at low temperatures, not flowing very quickly from the more distant areas. The Ink removal requires a greater vacuum. The area safe function of the nozzle print head but is limited to a narrow range of negative pressure. For this The reason for intense printing is the already heavily emptied ink supply earlier otherwise no longer allow secure printing. Still neat filled Ink reservoir this process is of little importance. Important though in this context, the temperature dependence, which, as described, on the basis of different, on the electronic memory chip stored parameters is calculated by the printer control. The printer controller knows the print intensity, i. those from the ink supply outflowing Ink liquid amount in a selected, elapsed time period, the operating temperature and the previously consumed amount of ink. Accordingly, the printer controller a temperature and pressure intensity-dependent residual ink removal amount to calculate. After that, it is judged whether printing at this time still with every intensity possible is. If the decision is negative, the printing is stopped and by the printer control prompting the user, the largely empty ink reservoir by a filled to replace.

To the approach described above is an alternative, which is that with slow-flowing ink in the foam a wait for the continuation of the printing process or the printing speed temporarily is lowered. This may result in the removal area of the foam again ink liquid accumulate until the requested printing performance is fulfilled again can.

It is for The documentation benefits that the amount of printing and cleaning spent ink, at least in the electronic memory module is stored in an irreversible, protected memory area becomes.

To further procedural measures It is suggested that the ink liquid arising during cleaning of the nozzle print head up in the ink reservoir fed again and that amount will be temporary the total in the printer control is not added or delayed is added. The cleaning ink is thus not for further use lost. This ink must be in a far away from the removal area Part of the foam supplied and will therefore be later again for removal. The time-dependent method requires that these amounts of ink temporarily from the further consumption available withdrawal quantities withdrawn, but after expiration of the ink reservoir (size, shape, Introduction connections u. Like.), for the foam and the ink liquid characteristic times are added again.

An alternative method is that the temperature-dependent determined amounts of ink are stored in a memory area of the electronic memory module in individual memory cells for each cleaning process and a predetermined period of time is scheduled to the mathematical consideration of the respective amounts of ink. When determining the remaining ink removal quantities by the printer control, all ink quantities stored in this area are added to the currently valid consumption. From time to time, for example, every time a new entry in this memory area is to be made, the printer control checks whether there is enough time for each of them followed entries has expired, so that the corresponding amount of ink for further use is available again. In the event that this condition applies, the entry is deleted.

For this another method is practiced such that in the electronic Memory module a time-dependent Managed memory area is set, with the one at Cleaning process consumed amount of ink read out, the new temperature-dependent consumption accumulated by a suction and back into the storage area of the current period is written. This allows everyone sucking operations within a period of time. In new time periods the printer controller reads the consumption value into the relevant one Memory location and deletes this in the other memory location. The in the then broken Period of time by exhausting all consumed quantities of ink will be deposited again in the new location.

The Invention is further developed by the fact that before each print job or before each print page the remaining amount of ink is calculated and in case that a value smaller than a fixed predetermined value is detected will, a signal for triggered the user will, the ink reservoir switch.

The Device for determination and monitoring the current amount of ink in an ink reservoir an ink printer of the matrix printer type, goes from a prior art from, wherein the ink reservoir filled with fine capillary foam and via a fluid connection with a jet print head connected to the pressure nozzles to a cleaning device is tightly adjustable and provided a connectable suction pump is and wherein in the printer control and the ink reservoir a communicating arranged electronic memory module for parameters of the ink liquid properties are.

These Device is further developed such that the existing on the ink reservoir Memory module and the memory in the printer control either via a Contact interface or a contactless RF interface communicate and that a temperature sensor in each case in the vicinity of the ink reservoir and of the nozzle print head is provided, the measured values in the electronic memory via a Signal line can be transferred to the printer control. This can influence the Ambient temperature and the printer as well as other parameters the determination of the current residual ink quantities considered become.

The Result can be made even more accurate depending on the application conditions by being attached to the ink reservoir and the nozzle print head each directly a separate temperature sensor arranged are.

For the special Case of a foam filled Ink reservoir is provided that in the ink reservoir a vacuum sensor with Signal line is provided for printer control. This can the determination of the remaining ink quantity even more accurate respectively.

In the drawing are embodiments of Invention, which are explained in more detail below.

It demonstrate:

1 Block diagram of the ink reservoir with nozzle print head, cleaning device and suction pump,

2 essentially the assemblies of 1 with a return line for extracted ink,

3 FIG. 2 schematically shows the ink printer with a printer controller with an interface between contacts between the printer controller and the memory module; FIG.

4 also schematically the ink printer with printer control, ink reservoir and memory module, which is contactlessly connected via an RF interface with the printer control,

5 a memory protected memory area,

6 a memory area for time-dependent management of ink consumption by cleaning the nozzle print head and

7 an alternative storage area for time-dependent management of ink usage by cleaning the nozzle print head.

The ink printer 1 ( 1 ) has an ink reservoir 2 that with ink liquid 2a is filled. At the ink reservoir 2 there is an electronic memory module 3 that either through a contact interface 14 (see. 3 ) or contactless via an RF interface 15 (see. 4 ) with the printer control 13 connected is.

The nozzle print head 7 is via a fluidver binding 5a at the with fine capillary foam 4 filled ink reservoir 2 in a withdrawal area 5 connected so that ink fluid 2a in the direction of the arrow, for example. By vacuum, continuously into the nozzle print head 7 flows and from there in the pressure nozzles 8th to characters or pictures u. Like. Is processed on a usually made of paper record carrier.

The nozzle print head 7 is on a (not shown) printhead carriage perpendicular to the plane and herverfahrbar. At the end there is a cleaning device 9 to which the nozzle print head 7 can be made pressure-tight. To the cleaning device 9 is a suction pump 21 connected, with extracted ink (so-called waste or dirty ink) via a return line 12 in a return area 6 of the ink reservoir 2 (see. 2 ) and can be provided again for printing.

The determination of the instantaneous amount of ink liquid in the ink liquid reservoir 2 takes place very accurately when printing and / or cleaning the nozzle print head 7 By removing the used amounts of ink liquid 2a through at least in the area of the ink reservoir 2 and / or the nozzle print head 7 measured temperature values and other physical parameters in the printer control 13 converted to a standard value and an ink quantity assigned to it in the printer control 13 calculated and stored continuously. For this communicates with the ink reservoir 2 and in the printer controller 13 existing memory either via the contact interface 14 ( 3 ) or the contactless RF interface 15 ( 4 ). Each near the ink reservoir 2 and the nozzle print head 7 is a temperature sensor 10 arranged, the measured values in the electronic memory of the printer control 13 via a signal line 11 be transmitted.

For this purpose has the ink reservoir 2 an electronic storage area 16 that over the interfaces 14 or 15 with the memory of the printer controller 13 communicates ( 5 ). The electronic storage area 16 indicates an irreversibly protectable storage area 17 on. The storage area 17 has "n" memory locations 17a . 17b ... 17n . 17p ... 17z and is with a write - write protection 18 , and writing posts 18a ... 18z Mistake.

According to 6 owns the memory module 3 a storage area 19 in which in individual memory cells 19i During each cleaning process, the temperature-dependent determined amount of ink is deposited in this process. In another, associated with this memory cell 19ii a characteristic describing the time of this extraction process is deposited.

Another method emerges 7 , On the electronic memory module 3 of the ink reservoir 2 is a storage area 20 determined by "m" memory locations, which is managed time-dependent Each of the "m" memory locations 20 / m ... 20/1 a period of time (eg a day) is assigned. During a cleaning process in the current period of time is the printer control 13 the amount of ink consumed so far for this period by suction and the new temperature-dependent consumption added by a suction and added back to the storage location 20 / m of the current time period written. After the beginning of a new time period, the printer controller reads the consumption value in the memory location 20 / m, write this in the memory location 20 / m - 1 and clears the contents in the memory location 20 / M. Upon reaching the next period, the content of the memory location becomes 20 / m - 1 in the memory location 20 / m - 2 transmit the contents of the memory location 20 / m again after 20 / m - 1 shifted and the contents deleted in 20 / m. This process is repeated accordingly. In the end, content reaches the memory location after m-1 time periods 20 /1. The amount of ink deposited there now had m-1 time periods from the return area 6 of the foam 4 back to the withdrawal area 5 decrease.

As soon as a value less than a predetermined value is determined close to zero, the user is prompted by the signal, the emptied ink reservoir 2 to replace it with a filled one. In addition, the last of the "n" will be read-only memory locations 17 described with the appropriate coding, the write protection 18 set and thus the ink reservoir 2 blocked for further use. The end of the ink liquid supply is determined in this way not only due to the number of dropped drops, but also temperature and time-dependent over the entire printing operation.

At the ink reservoir 2 and to the nozzle print head 7 can each directly a separate temperature sensor 10 be provided.

In addition, in addition to the ink reservoir 2 a vacuum sensor 22 with signal line 11 for printer control 13 to be built in.

Basically, the memory management of 5 - 7 in the memory module 3 and in the memory of the printer controller 13 be set up in the same way. However, it is also possible that the structure of the printer control 13 resulting memory too use.

1

ink printers

2

Ink reservoir

2a

ink liquid

3

electronic memory chip

4

feinkapillarer foam

5

removal area of the ink reservoir

5a

fluid communication

6

Restoration area

7

Nozzle print head

8th

pressure nozzles

9

cleaning device

10

temperature sensor

11

signal line

12

Return line for aspirated ink

13

printer control

14

Contact interface

15

contactless RF interface

16

electronic Storage area on ink reservoir

17

protectable electronic storage area

18

locations with write protection

19

storage area for time-dependent management

20

storage area for time-dependent management

21

suction Pump

22

Under pressure sensor

Claims (19)

Method for determining and monitoring the instantaneous amount of ink liquid in an ink reservoir ( 2 ) of an ink printer, wherein the ink liquid ( 2a ) under changing temperature and viscosity from the ink reservoir ( 2 ) coated with fine capillary foam ( 4 ) is filled via a fluid connection ( 5a ) into a nozzle print head ( 7 ) and in the form of drops for printing characters, images u. Like. Is ejected, and in the measured values in an electronic memory module ( 3 ) written to the printer controller ( 13 ), characterized in that by printing and / or cleaning the nozzle print head ( 7 ) consumed quantities of ink liquid ( 2a ) by at least in the area of the ink reservoir ( 2 ) and / or the nozzle print head ( 7 ) measured temperature values and other physical parameters in the printer control ( 13 ) is converted to a standard value and an amount of ink assigned to it in the printer control ( 13 ) is calculated and stored continuously. Method according to claim 1, characterized in that the quantity of ink consumed for printing or cleaning is stored in different storage locations ( 16 to 20 ) of the electronic memory in the printer controller ( 13 ) are stored. Method according to claims 1 or 2, characterized in that in a storage location ( 16 to 20 ) stores a standard temperature determined in accordance with the ink liquid supply, and also stores parameters describing the temperature dependence of the volume of ink removable from the ink supply. Method according to one of claims 1 to 3, characterized in that the characteristic for a type of ink drop volume at least in a storage location ( 16 to 20 ) of the electronic memory module ( 3 ) is deposited. Method according to one of claims 1 to 4, characterized that a correction factor and associated parameters for description the temperature dependence for the Ink liquid flow be stored during suction from the ink supply. Method according to one of claims 1 to 5, characterized in that for describing the Nachfließeigenschaften the ink liquid ( 2a ) in fine capillary foam ( 4 ) a time constant and associated parameters at least in the electronic memory module ( 3 ) and their temperature dependence in the printer control ( 13 ) are calculated. Method according to one of claims 1 to 6, characterized in that a correction factor for in the full ink reservoir ( 2 ) by removing the current operating temperature in the electronic memory of the printer controller ( 13 ) is calculated on the basis of the stored parameters. Method according to one of claims 1 to 7, characterized in that when printing by electronic pulses in the printer control ( 13 counted ink drops, by measuring the operating temperature in the area of the nozzle print head ( 7 ) is compared with a stored drop volume at standard temperature and thereby the current drop volume is determined. Method according to one of claims 1 to 8, characterized in that depending on the negative pressure and a suction time, the viscosity and the properties of the fine capillary foam ( 4 ) and the stored parameters, the amount of cleaning ink is determined. Method according to one of claims 1 to 9, characterized in that the printer control ( 13 ) due at least in the electronic memory module ( 3 ) performs an evaluation of the total amount of ink present, such that a time constant is taken into account which at least the design of the ink reservoir ( 2 ), the capillary properties of the foam ( 4 ) and the flow properties of the ink liquid ( 2a ). A method according to claim 10, characterized in that when slow in the foam ( 4 ) ink is allowed to continue to print, or the print speed is temporarily lowered. Method according to one of claims 1 to 11, characterized in that the amount of ink consumed by printing and cleaning, at least in the electronic memory module ( 3 ) in an irreversible, protected memory area ( 17 ) is stored. Method according to one of claims 1 to 12, characterized in that during cleaning of the nozzle print head ( 7 ) resulting ink liquid ( 2a ) in the top of the ink reservoir ( 2 ) and that this amount is temporarily the total amount in the printer control ( 13 ) is not added or delayed added. Method according to one of claims 1 to 13, characterized in that in a memory area of the electronic memory module ( 3 ) in individual memory cells ( 19 ) for each individual cleaning process, the temperature-dependent determined amounts of ink are deposited and a predetermined period of time is scheduled to the mathematical consideration of the respective amounts of ink. Method according to one of claims 1 to 14, characterized in that in the electronic memory module ( 3 ) a time-dependent managed memory area ( 20 ), wherein the amount of ink consumed during a cleaning process is read out, the new temperature-dependent consumption is added up by a suction process and returned to the storage area (FIG. 20 ) of the current time period is written. Method according to one of claims 1 to 15, characterized in that before each print job or before each print page, the residual ink quantity is calculated and in the event that a value is determined smaller than a fixed predetermined value, a signal for the user is triggered, the ink reservoir ( 2 ) switch. Device for determining and monitoring the instantaneous ink fluid quantity in an ink reservoir ( 2 ) of an ink printer of the matrix printer type, wherein the ink reservoir ( 2 ) with fine capillary foam ( 4 ) is filled and via a fluid connection ( 5a ) with a nozzle print head ( 7 ) connected to the pressure nozzles ( 8th ) to a cleaning device ( 9 ) is tight and a connectable suction pump ( 21 ) and wherein in the printer control ( 13 ) and at the ink reservoir ( 2 ) a communicating electronic memory module ( 3 ) are arranged for parameters of the ink liquid properties, characterized in that the on the ink reservoir ( 2 ) existing memory module ( 3 ) and the memory in the printer controller ( 13 ) either via a contact interface ( 14 ) or a contactless RF interface ( 15 ) and that a temperature sensor ( 10 ) in each case in the vicinity of the ink reservoir ( 2 ) and the nozzle print head ( 7 ) whose measured values are stored in the electronic memory of the printer controller ( 13 ) via a signal line ( 11 ) into the printer control ( 13 ) are transferable. Device according to claim 17, characterized in that on the ink reservoir ( 2 ) and on the nozzle print head ( 7 ) each directly a separate temperature sensor ( 10 ) are arranged. Device according to one of claims 17 or 18, characterized in that in the ink reservoir ( 2 ) a vacuum sensor ( 22 ) with signal line ( 11 ) for printer control ( 13 ) is provided.