JP4921602B2 - Recording device - Google Patents

Description

  The present invention relates to a recording apparatus.

  Conventionally, inkjet recording apparatuses have been widely used in printers, copiers, and the like for reasons such as low noise, low running costs, and easy downsizing of the apparatus. Recently, an ink jet recording apparatus using a thermal energy as an energy and ejecting ink by bubbles generated thereby is becoming widespread.

  In such an ink jet recording apparatus, in order to stably eject ink from the recording head, head characteristic information is provided in a storage area provided in the recording head (Patent Document 1). Based on this information, the drive conditions specific to the print head are selected from the head drive conditions prepared in the inkjet print apparatus, and the drive is performed based on information such as the environmental temperature and print head temperature provided in the inkjet print apparatus. Control is in progress.

  The drive conditions unique to the print head described above are conditions that take into account manufacturing variations in the manufacture of the print head ejection elements and the wiring leading up to the elements, and this condition applies to a large number of print heads manufactured. In order to be able to set a value specific to each print head, the print head has a storage element (memory) to store the information described above, and the head drive is based on that information when the ink jet printing apparatus is mounted. I do.

  In recent years, in addition to the background described above, the inkjet recording apparatus has realized both high-speed printing and high-quality printing such as photographic image quality. For this compatibility, the recording head (especially a color head) is used mainly for high-speed printing. Many configurations have been adopted that enable ejection of a plurality of ink ejection amounts, such as a large ink ejection amount of ˜5 pl and a small ink ejection amount of 4-1 pl used during high image quality printing.

JP-A-7-52388

  However, in the conventional ink jet recording apparatus, as described above, since the drive condition information is stored for each of two or more types of ink discharge amounts or for each of a plurality of colors, the capacity of the storage element of the recording head increases, and the storage element having a large capacity Therefore, there is a problem in that the cost of the recording head becomes high.

  Some of the storage elements of the recording head employ a Fuse ROM, and this ROM format forms arbitrary information by a combination of cutting / uncutting of the Fuse. Since it is necessary to cut the fuse, and the information increases, the cutting process time increases. As a result, there is a problem that the manufacturing time per recording head becomes longer.

The present invention has been made in view of the problems of the conventional techniques as described above,
By efficiently storing the drive condition information stored in the recording head, it is possible to suppress an increase in the capacity of the storage element, and the recording head capable of discharging two or more types of ink is the same as the conventional one. An object of the present invention is to provide an inexpensive inkjet recording head and inkjet recording apparatus that can output a recorded image by stable ink ejection.

  In order to achieve the above object, a recording apparatus of the present invention includes a first element array having a plurality of first recording elements for ejecting ink, and an amount of ink different from the amount ejected by the first recording element. Holds a second element array having a plurality of second recording elements for ejection, a first rank value of the first element array, and a shift number for calculating a second rank value of the second element array And a head-side memory unit that allocates a storage capacity for holding the shift number smaller than a storage capacity for holding the first rank value, and when the plurality of the recording heads are manufactured, The distribution of the first rank value and the distribution of the second rank value have a correlation, and the manufacturing process is performed between the peak of the distribution of the first rank value and the peak of the distribution of the second rank value. Due to variability A first head having drive information corresponding to the first rank value and driving information for driving the first print element, and the second print element corresponding to the second rank value. A main body side memory means for holding a second table having drive information for driving; a computing means for computing the second rank value using the first rank value and the shift number; Drive information is acquired from the first table based on the first rank value, the drive of the first recording element is controlled based on the drive information, and the second table is controlled based on the second rank value. And a control means for controlling the driving of the second recording element based on the driving information.

  As described above, according to the present invention, it is possible to store information for appropriately driving the recording head while suppressing an increase in the capacity of the memory means (storage element) provided in the recording head. Further, in the form using the FuseROM as the memory means, the FuseROM cutting process time can be shortened.

1 is a schematic perspective view of a recording apparatus. FIG. 2 is a perspective view of an ink jet cartridge used in the recording apparatus of FIG. 1. FIG. 3 is a diagram of the recording head described in the first embodiment viewed from the ejection direction side. Table of pulse width (drive information) for head rank. The figure which shows distribution of a rank number about 10,000 manufactured recording heads. FIG. 9 is a diagram of a recording head described in the second embodiment as viewed from the ejection direction side. The figure which shows the relationship between a Fuse required capacity | capacitance and a cutting process time. The control flow in an embodiment. FIG. 3 illustrates a control configuration of a recording apparatus.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

<Embodiment 1>
FIG. 1 is a perspective view showing a schematic configuration of a recording apparatus to which a recording head for performing recording according to an ink jet system according to an embodiment of the present invention can be attached.

  In FIG. 1, C is an ink jet cartridge (hereinafter referred to as a cartridge) having an ink tank above it and a recording head below it, and further provided with a connector for receiving a signal for driving the recording head. A carriage for mounting a plurality of cartridges C. The ink tanks of the plurality of cartridges C store different color inks such as yellow, magenta, cyan, and black inks. In addition, the carriage 2 is provided with a connector holder for transmitting a signal for driving the recording head of each cartridge C, and is electrically connected to the recording head. In the example shown in FIG. 1, four cartridges C that store magenta, yellow, cyan, and black inks in their respective ink tanks are mounted from the left.

  11 is a scanning rail that extends in the scanning direction of the recording head (main scanning direction) and slidably supports the carriage 2, 52 is a carriage motor, and 53 is a carriage for reciprocating the carriage 2 in the main scanning direction. Driving belts 5 and 6 and 7 and 8 for transmitting the driving force of the motor 52 are arranged before and after the recording position of the recording medium by the recording head, and a pair of conveying rollers for holding and conveying the recording medium, P is paper, etc. Recording medium. The recording medium P is pressed against a guide surface of a platen (not shown) that regulates the recording surface to be flat.

  The recording head provided in the cartridge C mounted on the carriage 2 protrudes downward from the carriage 2 and is positioned between the transport rollers 6 and 8, and the ejection port forming surface on which the ejection port of the recording head is formed is The recording medium P faces the guide surface of a platen (not shown) in parallel with the recording medium P. In this recording apparatus, a recovery system unit is disposed on the home position side on the left side of FIG.

  In FIG. 1, regarding this recovery system unit, reference numeral 300 denotes a cap unit that can be moved up and down in the vertical direction and is provided corresponding to each of the recording heads provided in each of the four cartridges C. When the carriage 2 is at the home position, the cap unit 300 is joined to the recording head and capped to prevent evaporation of the ink in the ejection port of the recording head, thereby increasing the viscosity of the ink, or Volatile components are prevented from evaporating and sticking to cause ejection failure.

  Further, the inside of the cap unit 300 communicates with a pump unit (not shown). The pump unit generates a negative pressure as required. The timing for generating the negative pressure is, for example, when the recovery of suction is performed by joining the cap unit 300 and the recording head in the event that the recording head becomes defective, or ink preliminarily discharged into the cap of the cap unit 300 For example, when empty is sucked.

  Reference numeral 401 denotes a preliminary discharge receiving portion provided on the opposite side to the home position across the recording operation area for the recording medium P. The preliminary discharge receiving portion 401 performs preliminary discharge of the recording head. Furthermore, the recovery system unit may be provided with a blade formed of an elastic member such as rubber to wipe the droplets adhering to the ejection port forming surface of the recording head. In addition, in order to eliminate the pushing of unnecessary objects due to wiping into the discharge port, preliminary discharge is performed after wiping to stabilize the discharge state.

  In the recording apparatus of this embodiment, the conveyance drive motor for conveying the recording medium P and the drive motor for operating the recovery system unit are made common and common.

  FIG. 2 is a perspective view of an ink jet cartridge C in which a recording head and an ink tank are integrated.

  As shown in FIG. 2, the cartridge C has an ink tank T on the upper side and a recording head 86 on the lower side. Further, an air hole 84 is aligned with the ink tank T in the upper part of the ink tank T. A head-side connector 85 is provided at the position. The connector 85 receives a signal for driving the recording head 86 and outputs an ink remaining amount detection signal. The recording head 86 is formed with a discharge port surface 1 having a plurality of discharge ports that open to the bottom side in the lower part of the drawing, and is necessary for discharging ink to the liquid path portion communicating with each discharge port. An electrothermal converter that generates thermal energy is disposed.

  FIG. 3 is a schematic view of a recording head having three ejection port groups that eject inks of three colors (C, M, and Y) at 5 pl and 2 pl, respectively, as viewed from the ejection direction side. In FIG. 3, the recording head includes a nozzle row that ejects ink with a first ejection amount (5 pl) and a nozzle row that ejects ink with a second ejection amount (2 pl).

  Reference numeral 31 denotes an ejection port capable of ejecting 5 pl of ink. Although not shown, each ejection port is provided with a recording element (hereinafter referred to as a heater board) that heats the ink in order to apply a voltage to eject the ink. ing. 32 is a discharge port capable of discharging 2 pl, and a heater board is present as in the case of 5 pl.

  A semiconductor element is generally used for the heater board, and its size has a strong correlation with the ink discharge amount. For this reason, variations in the manufacturing process of the recording head, particularly this heater size, have a great influence on ink ejection with a stable ejection amount. In addition, the drive voltage is supplied from the power supply of the printer main body via the recording head attaching / detaching portion on the main body side, but the resistance of the wiring from the contact on the recording head side to these heaters varies slightly but stable ejection. This affects the amount of ink ejected.

  Specifically, due to variations in the heater size manufacturing process and wiring resistance from the contact on the recording head side to these heaters, even if the main body of the inkjet printer is driven at the same voltage and application time, the discharge amount and discharge Discharge conditions such as speed cannot be made uniform.

  Therefore, in the conventional ink jet printer, in order to make the discharge conditions such as the discharge amount and discharge speed different for each print head uniform, the above-described variations in heater size and wiring resistance that the print head can have (hereinafter abbreviated as head rank). The head drive control considering the above is performed.

  FIG. 4 shows a control table in which the pulse width of a single pulse with respect to the head rank described above is changed in the head drive control performed by the ink jet printer. It is a data table provided with a plurality of drive information corresponding to this head rank.

  The rank number is determined by measuring the pulse threshold at which ink starts to eject from the nozzle while changing the pulse width in units of the drive resolution of the inkjet printer under a constant applied voltage (different from the main unit voltage) when the head is manufactured. A rank number is assigned to each. The assigned rank number is stored in a storage element in each recording head, and when mounted in an ink jet printer, head drive control is performed to select a drive pulse corresponding to that number.

  As shown in FIG. 3, in a recording head having a nozzle array that ejects 5 pl and a nozzle array that ejects 2 pl, a rank number is assigned to each nozzle array to satisfy each ejection condition. In this case, the number (number of data) of rank number information stored in the storage element (memory means) provided in the recording head is doubled.

  For example, in a recording head capable of ejecting three types of ink ejection amounts, the data amount for the rank number information stored in the storage element of the recording head in order to satisfy each ejection condition is tripled. As described above, in a recording head capable of ejecting N types (an integer of 2 or more) of ink ejection amounts, the amount of rank number information stored in the storage element of the recording head to satisfy each ejection condition is N times. turn into.

  In such a print head capable of discharging two or more ink discharge amounts, the rank number must be stored in the storage element of the print head in addition to the manufacturing variation that can be considered with one discharge amount. Inevitably, an increase in the capacity of the memory element could not be avoided.

  FIG. 5 is a distribution of rank numbers when the 10000 recording heads of 5 pl and 2 pl shown in FIG. 3 are manufactured. The pulse resolution per rank is 48 Mhz (about 0.02 μsec) for both 5 and 2 pl. The distribution of 51 represents a rank number distribution of 5 pl, and the distribution of 52 represents a rank number distribution of 2 pl. The distribution of 51 and the distribution of 52 are very similar. In other words, the distribution of 51 and the distribution of 52 have a strong correlation (correlation).

  Focusing on 51 distribution peaks and 52 distribution peaks, it can be seen that the distance between the two peaks (difference in rank value) is separated by 3 ranks as indicated by 53. That is, three addresses of the drive table shown in FIG. 4 are separated.

  Moreover, when the rank number of 2 pl of the recording head, whose rank number is 15 which is the peak of the distribution of 5 pl, was measured, most of them existed in rank 4 of 20, 19, 18, 17 centering on rank 18. It can be seen that it is distributed.

  As a result of the same measurement, the 2pl rank number of the recording head having a rank number of 5pl of 20 was mostly within 4 ranks around 23, and the 2pl of the recording head having a rank number of 5pl was 10 Most of the rank numbers were 13 and within 4 ranks.

  Therefore, the rank number information is stored in the memory means (storage means) provided in the recording head for the driving information of the two types of nozzles using the correlation described above.

  For example, based on the results of FIG. 5, a nozzle (nozzle row) corresponding to one ink discharge amount without assigning a rank number to each discharge amount in a head capable of discharging two types of ink discharge amounts, One rank number is stored in the memory means from the rank range in consideration of variations in the manufacturing process. The drive information of the ink jet printer main body is selected as the direct rank number as it is. The nozzle (nozzle row) corresponding to the other ink discharge amount is configured to have one rank number from the drive information within the rank range by utilizing the correlation.

  In other words, for one drive information, one rank information is selected from the drive control range (L) and stored in the memory means. The other drive information is a part of the drive control range, and one rank information is selected from a predetermined range (S) and stored in the memory means. Here, L> S. In the above description, L = 32 and S = 4.

  Here, the designation (setting) of a predetermined range which is a part of the drive range is performed based on a distribution peak shift (in other words, an offset amount) as indicated by 53 in FIG. Then, the distribution peak of FIG. 5 is designated (set) so as to be located at the center or almost the center of the predetermined range.

  The rank number determination method that suppresses the storage element capacity of the recording head described above will be specifically described in the case where a fuse ROM (fuse ROM) is used as the storage element of the recording head (cartridge).

  The rank range when the manufacturing variation of the ink ejection amount 5 pl is taken into consideration is 0.46 to 1.08 μsec, and 32 ranks are required when the drive pulse resolution is 0.02. To actually assign 32 ranks from rank numbers 0 to 31 with FuseROM, a capacity of 5 bits is required. Since the rank number of 5 pl corresponds to the selection number of the head drive pulse of the ink jet printer body as it is, if the rank number of 5 pl is 15, the head drive pulse corresponding to the value is selected.

  On the other hand, the rank number of 2 pl assigns 2 bits instead of 5 bits in order to suppress the capacity of the FuseROM. As described above, since the correlation with the rank number of 5 pl is used, it is possible to allocate a small Ruse ROM capacity. Here, based on the above-described actual measurement data, it is set as a shift number value having 2 types of 4 bits.

  Note that the above-described offset value (3 which is the peak-to-peak distance) is stored in the memory means of the recording apparatus. Then, the recording apparatus has a table of pulse width information (0.46 to 1.08 μsec) corresponding to the nozzle of 5 pl as the driving information of the recording head, and the nozzle of 2 pl offset by at least 3 ranks (3 addresses). The pulse width information (0.52 to 1.14 μsec of the pulse width) corresponding to is stored in the memory.

  As a result, the rank number of 2 pl can be determined by adding (calculating) using a rank number X of 5 pl, an offset value Y, and a shift number value Z of 2 pl. It becomes possible to assign to either.

As for a specific example of the assignment of the shift number Z of 2 pl, a case where the rank number X of 5 pl described above is 15 will be given as a specific example. In this case, the rank number of 2 pl exists within the four rank ranges of the total number 20, 19, 18, 17 around the rank 18.
When the rank number of 2pl is 20, since rank number X of 15p = 15 and offset value Y = 3, 2 is assigned to the shift number Z.
When the 2pl rank number is 19, since the 5pl rank number X = 15 and the offset value Y = 3, 1 is assigned to the shift number Z.
When the rank number of 2pl is 18, since rank number X of 15p = 15 and offset value Y = 3, 0 is assigned to shift number Z.
When the 2pl rank number is 17, since the 5pl rank number X = 15 and the offset value Y = 3, −1 is assigned to the shift number Z.

  In the above description, when different expressions are used, for the first nozzle row, the first drive table having a plurality of drive values corresponding to the first nozzle row and the drive of the first nozzle row held in the print head are used. It can be said that the drive value is selected for the first nozzle row based on the value selection information.

  In addition, for the second nozzle row, a second drive table having a plurality of drive values corresponding to the second nozzle row, drive value selection information for the first nozzle row, and drive value selection information for the second nozzle row It can be said that the drive value is selected for the second nozzle row based on the information regarding the offset.

  Supplementally, the rank number X is driving information selection information for the first nozzle array, the shift number value Z is driving information selection information for the second nozzle array, and the offset value Y is information related to offset.

  As described above, by checking the rank distribution of each ink discharge amount at the time of manufacture and using the result, it is possible to suppress an increase in the capacity of the storage element included in the recording head and to discharge conditions for each ink discharge amount. Can be stored.

  FIG. 9 is a control configuration diagram of the recording apparatus. The control unit 90 of the recording apparatus includes a CPU 91, an ASIC 94, a ROM 92, and a RAM 93. The CPU 91 uses the ASIC 94 to control the operation of the recording apparatus. The ASIC 94 is provided with a recording head drive control block, a carriage motor control block, an HV conversion circuit, and the like. The ROM 92 is provided with a control program for the CPU 91, a head drive table, motor control information, and the like. Further, the cartridge C is provided with a Fuse ROM 95.

  FIG. 8 is a control flow executed by the CPU 91. In this flow, for example, in step S1, the rank number and shift number of 5 pl are read from the Fuse ROM 95 provided in the cartridge C. In step S2, offset information is read from the ROM 92 of the control unit 90.

  In step S3, for the 5 pl nozzle row, pulse width information is selected from the drive table based on this rank number, and the selected pulse width information is set in the setting portion for the 5 pl nozzle row of the drive control block of the recording head.

  In step S4, pulse width information is selected from the drive table based on the 5pl rank number, offset information, and shift number for the 2pl nozzle row, and is set in the setting unit for the 2pl nozzle row of the drive control block of the recording head. Set the selected pulse width information. Thereafter, when user operation or image data is input from the outside, the recording head is driven based on the set information, and the recording head records an image on the recording medium.

  This control flow is executed, for example, when the recording apparatus is turned on or when a cartridge is mounted on the recording apparatus.

<Embodiment 2>
In the first embodiment, two types of ink ejection have been described. In the second embodiment, three types of ink ejection will be described. In this embodiment, points different from the first embodiment will be described, and other descriptions will be omitted.

  With reference to FIG. 6, a description will be given of a rank number determination method of 2 pl and 1 pl and allocation of a Fuse ROM capacity in a recording head capable of ejecting three types of ink, ie, 5 pl of 61, 2 pl of 62, and 1 pl of 63.

  As described in the first embodiment, the rank number of 2 pl is almost within 4 ranks centered on the value offset by 3 ranks. It was also found that the 1 pl rank number was almost within 4 ranks centered on the value offset by 4 ranks from the 5 pl rank number.

  Based on this result, similarly to the 2 pl rank number determination method, the 1 pl rank number determination method also allocates the FuseROM capacity of 2 bits to have one of the four types of shift number values. The offset value Y2 of 1 pl is stored as 4 in the storage area in the main body of the ink jet printer, and can be determined by adding the rank number X of 5 pl, the offset value Y2 and the shift number value of 1 pl.

  That is, the memory means of the print head holds 9 bits of information including 5 pl rank information 5 bits, 2 pl rank information 2 bits, and 1 pl rank information 2 bits.

  FIG. 7 shows the three items of the required volume of Fuse, the cutting process time, and the ink discharge stability of each ink discharge amount in a recording head capable of discharging three types of ink with the ink discharge amounts of 5 pl, 2 pl, and 1 pl. The rank number determination method of the invention was compared with the conventional rank number determination method.

  With respect to the ink discharge stability of each ink discharge amount, both methods satisfy both the discharge amount and the discharge speed. In contrast to the FuseROM capacity, the conventional method requires 15 bits, whereas in the present embodiment, 9 bits, which is about 40% less, can be allocated efficiently. In addition, the FuseROM cutting process time when manufacturing 10,000 recording heads is 0.1 sec. Since the time required for cutting 1 bit is 0.1 sec, the conventional method can be shortened to 15000 sec and 9000 sec in the present invention by about 100 min. It has become. Furthermore, the recording head can be produced at a much lower cost with respect to the manufacturing cost of the recording head by both reducing the storage element capacity and shortening the cutting process.

  As described above, according to the present invention, in a recording head capable of ejecting two or more types of ink ejection amounts, the rank distribution of each of the different ink ejection amounts is investigated at the time of manufacturing the recording head, and the result is used. Thus, it is possible to store the drive condition information that suppresses the increase in the capacity of the storage element included in the storage element and satisfies the discharge condition of each ink discharge amount.

  Further, in the recording head configuration in which the Fuse ROM is used as the storage element of the recording head, it is possible to shorten the Fuse ROM cutting process time. As a result, it is possible to reduce the manufacturing cost of the recording head from the viewpoint of suppressing the increase in the storage element capacity and the manufacturing process time in the recording head capable of ejecting two or more types of inks. Can be provided to.

<Other embodiments>
As described above, the first embodiment and the second embodiment are not limited to the above-described examples. For example, the number of ink ejection amounts may be four or more. Also, the drive control range is not limited to 32 or 4, and the possible value of the shift number is not limited to 4.

  In addition, the pulse width information is controlled as drive information in order to make the ink discharge conditions uniform, but the present invention is not limited to this, and the drive voltage value is controlled to make the ink discharge conditions uniform. It may be a drive voltage table.

Claims (4)

A first element array having a plurality of first recording elements for ejecting ink and a second element array having a plurality of second recording elements for ejecting an amount of ink different from the amount ejected by the first recording element A first rank value of the first element row, a shift number for calculating a second rank value of the second element row, and a storage capacity for holding the shift number as the first rank A head-side memory means allocated smaller than the storage capacity for holding the value, and when a plurality of the recording heads are manufactured, the distribution of the first rank value and the second rank value A recording head having a correlation, and having a predetermined deviation due to a variation in a manufacturing process between the distribution peak of the first rank value and the distribution peak of the second rank value;
A first table having driving information for driving the first recording element corresponding to the first rank value, and driving information for driving the second recording element corresponding to the second rank value. Main body side memory means for holding a second table;
A computing means for computing the second rank value using the first rank value and the shift number;
Drive information is acquired from the first table based on the first rank value, the drive of the first recording element is controlled based on the drive information, and the second information is calculated based on the second rank value. A recording apparatus comprising: control means for obtaining drive information from a table and controlling drive of the second recording element based on the drive information. The main body side memory means holds an offset value corresponding to the predetermined deviation,
The recording apparatus according to claim 1, wherein the calculation unit calculates the second rank value using the first rank value, the shift number, and the offset value.   The recording apparatus according to claim 1, wherein the driving information is a pulse width of a voltage applied to the first recording element and the second recording element.   The recording apparatus according to claim 1, wherein the drive information is a value of a voltage applied to the first recording element and the second recording element.

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