JPH05197233A - Replacing unit for electrostatic-photograph type copying machine - Google Patents

Abstract

PURPOSE: To maintain the output quality of a printer and to prolong the operation life of a cassette by allowing a printer control unit to receive history of application information from the cassette and adjust an operating parameter, when the cassette is inserted into the printer, as a cassette capable of making an exchange with a developing device and a programmable memory. CONSTITUTION: When the power of the printer is turned on, the number of printing times stored in a cassette memory 30 is read out and stored in the nonvolatile memory of the printing control unit 40. The printer control unit adjusts the levels of electrification, an exposure, a developing bias and an automatic density control system response, for a photoreceptor, according to this information. This printer is programed to synchronously update the number of the printing times in the cassette memory and even if the cassette is removed from the printer, the data is retained in the cassette.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatographic copying machine, and more particularly to an electrostatographic copying machine incorporating a replaceable unit.

[0002]

Replaceable units or cartridges used in electrostatographic copiers and printers are known. For example, in a certain copying machine, the photoconductor for the copying machine and its supporting device can be assembled as a processing unit, and this processing unit can be removed from the copying machine and replaced with a new processing unit if necessary. Similarly, a developing cartridge and a toner supply cartridge can be provided.

One replaceable unit for an electrostatographic reproduction machine is described in US Pat. No. 4,827,308. This unit contains a photoreceptor belt and various processing means, that is, processing means such as a developing device, a transfer corotron, a cleaner, and a charging corotron. An electrostatographic copier using a xerographic (including photoreceptor and means such as corotron) cartridge, developer cartridge and toner cartridge is described in U.S. Pat. No. 4,961,088. Each cartridge has an identification / memory chip in the form of an integrated EEPROM (Electrically Erasable and Programmable Read Only Memory). The chip is electrically connected to the copier when the cartridge is inserted. The EEPROM ensures that only approved cartridges are used in the copier, keeps a count of the images performed, and disables the cartridge when it reaches the end of its useful life. it can.

US Pat. No. 4,500,195 discloses a replaceable unit of an image forming apparatus, which comprises a photosensitive drum, a toner supply cartridge and a toner collecting container.
When manufacturing the replaceable unit, the arm outside the unit is set to a position that depends on the characteristics of the photosensitive drum, and when the replaceable unit is inserted into the copying machine, the arm automatically moves the copying machine. Set to operate under the most appropriate imaging conditions.

[0005]

A replaceable unit for an electrostatographic copier is not necessarily provided in the copier continuously throughout the life of the copier. For example, when different color toners are needed, the unit in use is removed and replaced with another unit temporarily. The present invention particularly relates to a unit having a built-in developing device, which has the best performance regardless of how many times the unit is detached from the copying machine and how many times the unit is used in different copying machines in its service life. To be obtained from.

[0006]

According to the present invention, there is provided a replaceable unit for an electrostatographic copying machine, which includes a developing device for developing a latent image on a circulating image forming member with toner and a unit for copying. A programmable memory arranged to be connected to the copier when it is inserted into the machine, receiving and storing an input from the copier indicative of the use of the unit,
A replaceable unit for an electrostatographic copier is provided wherein the memory directs the copier to use the unit and adjusts at least one operating parameter of the copier according to the use of the unit.

[0007]

1 shows a laser printer using a replaceable unit in the form of an electrostatographic cassette 1, the details of which are shown in FIGS. A flexible photoconductor belt type electrostatographic imaging member is housed in a cassette 1 along with other electrostatographic processing means described below. A raster output scanner (ROS) 2 produces an imaging beam 3 which is directed through an imaging slit in cassette 1 onto a photoreceptor belt to form an electrostatic latent image on the belt. The image is developed in cassette 1 and transferred to a copy sheet at transfer station 4. The copy sheet is supplied to the transfer station 4 from one of the four supply trays 5, 6, 7, and 8. The transferred image is the fixing station 9
At 1, the copy sheet is heat-fixed, and then the copy sheet is transferred from the printer and collected in a sample tray 10 at the top of the printer or a stack tray 11 at the side of the printer. Separately from this, a copy sheet having a fixed image on only one side is sent to a tray-less double-sided copy passage in the printer, returned to the transfer station 4, and transferred from the printer to one of the trays 10 and 11. You can also receive the image on the other side.

The raster output scanner 2 includes an imaging beam 3
It contains a He-Ne laser for generating, an ordinary rotating polygon for sweeping the beam on the surface of the photosensitive belt, and an acoustic modulator. The imaging image beam is modulated according to input signals received from a remote image source, such as a user interface and keyboard (not shown). The operation of this type of raster output scanner that produces a latent image on the photoreceptor is well known and requires no explanation here. Processing of the image signals from the remote image source is done by the printer's electronic unit 15 and the operation of the printer is generally a printer control unit (not shown) including one or more microprocessors and suitable memory holding printer operating software. ) Under the control of.

Cassette 1 is described in US Pat. No. 4,827,30.
It may be similar to that described in No. 8. As shown in FIG. 2, the cassette 1 includes, in addition to the photoconductor belt 20, a charging scorotron 21, a developing device 22, a transfer corotron 23, and a cleaning device 24. The charging scorotron 21 is located on the upstream side of the image forming slit of the cassette 1 and uniformly attaches electrostatic charges to the surface of the photoconductor belt 20 before the exposure of the image forming beam 3. The developing device 22 is located on the downstream side of the image forming slit, brings the mixed developer close to the electrostatic latent image on the photoconductor belt 20, and develops the electrostatic latent image.
The mixed developer is a two-component mixture and includes a toner and a magnetically attractable carrier. Toner is transferred to the photoreceptor belt 20 during image development, and replacement toner is periodically replenished into the container of the developing device 22 from a hopper (not shown). A transfer corotron 23, located at transfer station 4, assists in transferring the developed image from photoreceptor belt 20 to a copy sheet entering cassette 1. Finally, the cleaning device 24 removes the residual toner particles from the surface of the photoconductor belt 20 and then irradiates them with a discharge lamp to remove the electrostatic charge remaining on the photoconductor belt.

The above-mentioned cassette 1 is removable from the printer, and when any one of the processing elements deteriorates, the cassette 1 can be replaced with another cassette. Alternatively, it can be replaced by a cassette containing different color toners. Cassette 1
Is mounted on the upper surface of the cassette as shown in FIG.
It has a memory chip 30 in the form of an EPROM (electrically erasable and programmable read only memory). Contact pads 31 are provided on the chip 30 so that when the cassette is inserted into the printer, the chip 30 will automatically be connected to the printer control unit via the terminal block 32 of the printer portion 33. When inserted into the printer, the memory 30 receives and stores information from the printer control unit that reflects the use (ie history) of the cassette 1. For example, information about the number of prints can be received and stored when the cassette is located in the printer, and this information is retained when the cassette is removed from the printer for any reason.
This information is used to adjust one or more operating parameters of the electrostatographic system of the printer to take into account the history of the cassette, thereby maintaining printer output quality and extending the operating life of the cassette. .. The operating parameters that can be adjusted according to the information stored in the memory 30 are, for example, the charging level of the photoconductor, the exposure level, the developing bias level, and the response level of the ADC (automatic density control) system.

During normal operation of the printer, the ADC system measures the toner density of regularly generated prints and sends a signal to the printer control unit as necessary to operate the toner replenishment motor to develop toner. Supply to. The response of the printer control unit, ie the amount of toner replenished, is determined by the so-called ADC setpoint in the printer memory. Automatic density control (ADC) systems used in electrostatographic reproduction machines are well known and need not be described in detail here. Known automatic density control systems include means for generating a test patch on the photoreceptor and a sensor for measuring the reflectance of the developed patch to determine toner concentration, such a system being described, for example, in U.S. Pat. No. 4,551,004,
A test patch generating means suitable for the laser printer of FIG. 1 is described in US patent application Ser. No. R / 91016.

As the usage time of the cassette 1 increases, the developing characteristics of the developing device 22 change.
Even if the solid area developing ability can be made constant by the operation of the system, the line drawing developing ability of the printer is deteriorated. However, by adjusting the ADC set point with the usage time of the cassette, it is possible to restore the line drawing development performance at the expense of the solid area development (SAD) performance, thereby making the line drawing development performance constant over time. Instead, the SAD performance changes. In this way, the ADC setpoint can be adjusted by using the information contained in the cassette memory 30. When the cassette 1 shown in FIGS. 2 and 3 is inserted into the printer, the time information of the cassette is immediately supplied to the printer control unit. Further, since it is monitored by the printer control unit related to the memory 30, the ADC set point is determined when the density performance of the line drawing is deviated from the target performance level at every fixed time of the life of the cassette. Adjusted to restore the line drawing development performance. This is shown in FIG. 4, where the printer control unit 40 has an input from a conventional automatic density sensor (toner density monitor system) 41 and an input from the memory 30. The response of the printer control unit 40 to the signal from the automatic density sensor 40 is adjusted according to the input from the cassette memory 30, thereby adjusting the operation of the toner replenishment motor 42.

However, the SA resulting from the above procedure
Changes in D performance may not be acceptable.
In this case, a similar procedure can be used to adjust other parameters, such as the photoreceptor charge level, exposure level, and development bias voltage, according to the cassette usage time, while at the same time changing the ADC setpoint, and , Both the line drawing development performance and the SAD, that is, the solid area development performance are satisfied. In particular, the values of the ADC set point, the photoconductor charging level, the exposure level and the developing bias voltage can be selected to match the line drawing developing performance and the SAD performance to these requirements at any usage time of the cassette. Appropriate loops are added in parallel to the loops 42, 22, 41 of FIG. 4 for each added parameter to be adjusted.

Another effect that occurs with the aging of the cassette 1 is that the toner concentration in the reservoir of the developing device 22 decreases even if the print quality parameters are satisfied. The use of the cassette at such lowered toner concentration levels will shorten the life of the developer and thus the cassette. Adjustments to the parameters described above can also be used to mitigate such effects, so that all print quality parameters are at their desired levels over time for any cassette and toner density is at the desired level. The service life of the cassette can be extended.

The optimum operating parameters described above can be determined from empirical and theoretical data of multiple sample systems and can be retained in the printer control unit as a look-up table or algorithm. By storing the usage time of the cassette in the memory 30, even if the cassette is removed from the printer, the usage time of the cassette is stored, and since it is searched by the printer after reinserting the cassette in the printer, the accuracy and reliability can be improved. Highly the calibration tables and algorithms described above can be used.

Referring to FIG. 5, when the power of the printer is turned on, the print control unit 40 reads out the number of prints stored in the cassette memory 30.
Stored in the non-volatile memory (NVM). The printer is programmed to periodically update the number of prints in the cassette memory, that is, when the printer determines that the update is due, new data is stored in the cassette memory 3.
The data is written to 0 and then the data is retained even if the cassette is removed from the printer. For example, 200 prints since the cassette memory was previously updated.
The cassette memory can be updated at any time when the printer control unit determines that a failure has occurred. The printer control unit then checks the number of prints on the cassette to determine if the operating parameters of the electrostatographic system have reached values to be adjusted. For example, the printer control unit can be programmed to adjust the operating parameters when it determines that 800 prints have been made since the last adjustment. After that, when the print request is received, the printer control unit 40 counts the number of prints, and after the print run is completed, the total number of prints made during the print run is stored and the number of prints in the cassette memory is used for updating. .. Alternatively, the print count of the cassette memory can be updated during the print run instead of at the end of the print run. The printer is provided with information about the time the cassette has been used and can compensate for changes that occur as the development system ages, thus achieving improved performance with more efficient use of the toner available in the cassette.

Although the above description relates to the number of accumulated prints made while the cassette is in use, other factors may be used to indicate the cassette's usage time. For example, the cassette memory 30 can store the number of rotations of the photosensitive belt or the number of charging cycles generated in the cassette. These indirectly indicate the number of prints made together. Alternatively, the cassette memory 30 may store the area coverage (represented by the adjusted number of pixels) during use of the cassette. Alternatively, the cassette memory 30 may be continuously supplied with information about the difference between the target charge level of the photoconductor 20 and the actual charge level, and store the information as an instruction of the usage time of the cassette. When the cassette is removed from the printer, for example, a cassette containing toners of different colors is needed, so that the most recent measurement value indicating the cassette usage time is stored and immediately available for use by the printer control unit described above. ..

Although the above description relates to the cassette of FIGS. 2 and 3 used in a laser printer, this is not critical. A cassette incorporating a memory that stores information about the time the cassette has been used is described in US Pat. No. 4,82.
It can also be used in an electrostatographic copying machine of the type described in No. 7,308. Moreover, the cassette need not be of the type described above. The cassette can, for example, simply be a toner cassette and does not require the photoreceptor of the printer.

The cassette described above is described in US Patent Application No. R / 91.
No. 010 type printer, in which the number of pixels toned in a cycle of the photoreceptor is used to indicate the amount of toner to be applied to the developing device 22 in that cycle. .. In this printer, a toner density monitoring system is used to provide additional control over the amount of toner applied to the developer unit 22 in a given photoreceptor cycle.

[0020]

As described above, according to the present invention, the best performance can be obtained from the unit.

[Brief description of drawings]

FIG. 1 illustrates an electrostatographic printer.

2 is a schematic cross-sectional view of a replaceable unit of the printer of FIG.

FIG. 3 is a perspective view of the unit of FIG. 2 showing the connection of the units in the printer.

FIG. 4 is a block diagram showing a relationship between respective parts of the printer.

FIG. 5 is a flowchart showing a part of a printer operation procedure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cassette 2 ... Raster output scanner 3 ... Image beam 4 ... Transfer station 5, 6, 7, 8 ... Supply tray 9 ... Fixing station 10, 11 ... Sample tray 15 ... Electronic subsystem 20 ... Photosensitive belt 21 ... Charging Scorotron 22 ... Developing device 23 ... Fixing corotron 24 ... Cleaning device 30 ... Memory chip 31 ... Contact pad 32 ... Terminal block 40 ... Printer control unit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location G03G 15/08 112 11222-2H 115 9222-2H 15/16 (72) Inventor Krysztof Jersey Less UK London W 13 8 NQ Ealing Amherst Ave 19 (72) Inventor Robin Ashley Collins UK Bedfordshire ES 18 9 NJ Bigle's Wade Bloom High Road 8 (72) Inventor Shelley May Taylor UK Hertfordshire ES 2 8 Essette Stevenage Burley Close 44 The Elms

Claims (1)

[Claims] 1. A replaceable unit for an electrostatographic copying machine comprising: a developing device for developing a latent image on a circulating image forming member with toner; and a copying device when the unit is inserted into the copying machine. A programmable memory arranged to be connected to the machine, which receives and stores an input from the copier indicating the use of said unit, said memory instructing the copier to use said unit. A replacement unit for an electrostatographic copying machine, characterized in that at least one operating parameter of the copying machine is adjusted according to the use of the unit.