JP2000326500A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recognize a present state of a print head by reading data from a magnetic recording medium on the head when the head is again mounted even when the head is removed. SOLUTION: A magnetic tape 122 is adhered to an upper surface of a print head 101 placed on a carriage 106. Print attribute data containing an ink residue of the head is recorded at least by a magnetic head 120 on the tape 122 of the head 101 after the head is cleaned when printing is finished. When a power source is turned ON and the head is replaced, print attribute data of the head is read from the tape 122 of the head 101, and provided for controlling as desired.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a printer, a plotter, and a copying machine having one or a plurality of print heads, and more particularly to an image forming apparatus employing an ink jet recording system.

[0002]

2. Description of the Related Art In an ink jet recording system, a heater is mounted in a nozzle filled with ink, and a pulse signal is applied to the heater to heat the heater, thereby causing the ink to boil, thereby generating a bubble pressure. Is a method of ejecting ink. When this method is used for an image forming apparatus, one head is formed by arranging a plurality of nozzles, and a plurality of heads (for example, a plurality of heads for ejecting inks of cyan, magenta, yellow, black, etc.) are formed. Head) to form a full-color image when used in combination.

Prior to printing, the image forming apparatus needs to recognize which print head (for example, ink color) is mounted on which position on the carriage. Conventionally, the type of print head, such as color, has been set or identified by the following method. (1) Determined by the mounting position of the print head on the carriage. (2) A resistor or the like corresponding to the type of the print head is attached to the print head, and the type of the print head is determined from an electrical value such as a resistance value. (3) The print head is provided with an optically readable identifier such as a bar code, and the type of the print head is identified by reading the bar code or the like optically.

[0004]

By the way, for example, dynamic data that changes with the printing operation, such as the remaining amount of ink in each print head, cannot be managed by any of the above methods. The control unit manages the print head only while the print head is mounted on the image forming apparatus. Therefore, if the print head is removed from the image forming apparatus,
There is a problem that the data of the print head itself is initialized in the control unit, and when the print head is mounted again, the current state of the print head cannot be correctly recognized.

[0005] Even after the print head is removed, it is possible for the control unit of the image forming apparatus to continuously manage the data of the print head. In addition to the heavy load on the processing unit, if the removed print head is used in another image forming apparatus, it is not possible to continuously and correctly manage the state of the print head. It becomes possible.

The present invention has been made in view of such a background, and provides a magnetic recording medium readable and writable from the outside to each print head so that print attribute data can be written to the print head itself. By doing
An object of the present invention is to provide an image forming apparatus capable of reading data from a magnetic recording medium on a print head and recognizing a current state of the print head when the print head is remounted even when the print head is removed.

[0007]

In order to achieve the above object, an image forming apparatus according to the present invention comprises an image forming apparatus having at least one print head, wherein a carriage mounting the print head and a carriage are provided. Carriage driving means for reciprocating in one direction, means for monitoring at least print attribute data that changes with a printing operation of the print head, and movement of the carriage with respect to a magnetic recording medium provided to the print head And magnetic recording means for writing and reading the print attribute data.

By writing the print attribute data of the print head in the print head itself, even if the print head is detached from the image forming apparatus, the data recorded on the magnetic recording medium on the print head can be copied. By reading, the state at the time when the print head was used last can be recognized. As a result, for example, printing control can be performed in accordance with the state of the print head based on the print attribute data.

For example, the print head is an ink jet head, and the print attribute data that changes with the printing operation is data relating to the remaining amount of ink.

[0010] The print attribute data is preferably written into the timely recording medium at least after printing processing is completed, and is read out from the magnetic recording medium when the printhead is replaced and when the apparatus is turned on.

[0011]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a view showing a schematic configuration of a serial printer type ink jet image forming apparatus according to the present invention. FIG. 2 is a view of the carriage 106 of FIG. 1 as viewed from behind.

The print heads 101Bk, 101Y, 101
M, 101C, black, yellow, and the like from the ink tank via an ink tube (both not shown).
Magenta and cyan inks are supplied. Each print head 101 is driven by a print head driver or the like in accordance with a print signal corresponding to print data from a print control unit (to be described later with reference to FIG. 3).
Ink droplets are ejected from No. 1 to perform color recording on the printing paper 102. As shown in FIG. 2 on an enlarged scale, a magnetic tape 122 as a magnetic recording medium is attached to the upper surface of each print head 101. On the magnetic tape 122, data relating to the current state of the print head, such as the remaining amount of ink, is mainly written by the magnetic head 120. The magnetic head 120 is arranged, for example, at a position farthest from the home position so as to contact the upper surface of the print head 101 as the carriage 106 moves. The magnetic head 122 may be retracted to another position when not needed.

A sub-scanning motor (paper transport motor) 103 is a drive source for intermittently feeding the print paper 102, and drives a transport roller 104 via a gear. The main scanning motor 105 is connected to the carriage 10 on which the print head 101 is mounted.
Reference numeral 6 denotes a drive source for causing the scanning unit 6 to scan in the direction of arrow AB through the main scanning belt 107.

When the printing paper 102 is fed by the transport roller 104 and reaches a printing position, the paper transport motor 10
3 is turned off, and the conveyance of the printing paper 102 is stopped. Prior to the image recording operation on the printing paper 102, the carriage 106 is moved to the position of the home position (HP) sensor 108.
Then, forward scanning is performed in the direction of arrow AB, and black, yellow, magenta, and cyan inks are ejected from the predetermined positions from the print heads 101Bk to 101C to perform image recording. When image recording for a predetermined width (called a band) by one scan of the carriage 106 is completed, the carriage 106 is stopped, and conversely, the backward scan is started in the direction of arrow B to reach the position of the home position sensor 108. Return the carriage 106. By driving the paper conveyance motor 103 during the backward scanning, the print head 101Bk
The printing paper 102 for one band recorded at 101 C is conveyed. By repeating such a scanning operation of the carriage 106 (and the head 101) and a paper feeding operation, printing of the entire image is realized.

The linear scale 109 disposed adjacent to and parallel to the scanning path of the carriage 106 has a slit with a predetermined resolution. A signal of two phases (a phase difference of 90 °) is obtained by reading the slit of the linear scale 109 with a linear scale sensor 123 (FIG. 2), which is a transmission type optical sensor attached near the carriage 106. Based on this signal, the position of the carriage 106 is managed and the ink ejection of the print head 101 is synchronized.

FIG. 3 is a block diagram showing a configuration of control hardware of the image forming apparatus according to one embodiment of the present invention. The image forming apparatus shown in FIG. 1 includes a print control unit 202 and a head 101, and is connected to an external device 201. The external device 201 is a host device that supplies image data and various commands for recording to the image forming apparatus, and has a computer, an image reader, and other forms.

The print control unit 202 includes a linear scale 1
09, a main scanning motor 105, a sub-scanning motor 103, a magnetic head 120, and an operation panel 111 are connected.

The print control unit 202 controls the head 1 based on the image data VDI transferred from the external device 201.
01 is used to control the formation of an image on printing paper. The print control unit 202 includes a CPU 203, a head control unit 204, a counter 205, and a carriage / paper feed servo control unit 211. Among them C
The PU 203 interfaces with the external device 201 to which the serial image data VDI is transferred, and controls the operation of the entire print control unit 202 such as each memory and I / O.

More specifically, when the serial image data VDI is transferred from the external device 201, the image data VDI
Are temporarily stored in the image memory for several bands. The held image data VDI is subjected to various image processing, and the image data VDO is output in accordance with the scanning of the head 101.

The function of the linear scale 109 is as described above.

In the head control unit 204, an enable signal BE for each block of the head and a pulse signal H for driving the heater are provided.
E and other signals required for ink ejection are also generated.
Image data VDO output from the head control unit 204,
The block enable signal BE, the heater drive pulse signal HE, and the like are transferred to the head 101, and the control circuit in the head 101 causes each of the image data VDO and the enable signal (B
E, HE) are turned on only for the nozzles that are enabled. Ink is ejected from such nozzles and adheres to the printing paper to form an image for one row as shown in FIG. This is repeated by scanning the head 101 in the main scanning direction to form an image for one band. Next, the printing paper is fed by a predetermined amount, and an image for one band is formed again. By repeating such control, the entire image is formed on the printing paper.

The carriage / paper feed servo control unit 2
Reference numeral 11 denotes a driving speed of the main scanning motor 105 and the sub-scanning motor 103 based on the output from the linear scale 109.
The position management of the start / stop / movement amount is feedback-controlled.

The operation panel 111 has a print mode,
The user instructs the operation of the image forming apparatus, such as a demonstration print and a print head recovery operation instruction. In the present embodiment, the display of dynamic data is
It is performed in.

In this embodiment, under the control of the CPU 203, the magnetic head 122 is attached to the magnetic tape 122 attached to each print head 101 via the write / read control unit 20.
By 0, data of the remaining ink amount in the print head is recorded.

As is well known, ink is ejected from an ink jet print head by instantaneously heating the inside of a print nozzle of the print head to expand the ink and eject ink droplets by the pressure. Therefore, the size of the ejected dots is affected by changes in the pressure in the print head, the temperature of the nozzles and ink, the ambient temperature, and the like. Therefore, in order to keep the ejection state constant, the characteristics of the temperature sensor (not shown) in the print head, the remaining amount of ink in the print head, the characteristics of the heater for heating the ejection nozzles, the external temperature, etc. It is necessary to generate an ejection pulse according to the above parameters. For this purpose, it is necessary for the print head to detect dynamic data such as the characteristics of the temperature sensor in the print head, the remaining amount of ink in the print head, and the characteristics of the heater for heating the discharge nozzle. The characteristics of the temperature sensor in the print head can be corrected by adjusting the temperature in the print head to the ambient temperature while the temperature in the print head is stable. The discharge nozzle heating heater can be read from the value of the dummy resistance corresponding to the heater. Further, the remaining amount of ink in the print head can be detected with a certain degree of accuracy by counting the dots ejected from the print head.

In these dynamic print attribute data, except for the remaining amount of ink in the print head can be obtained by activating a detection sequence.
When the print head is removed from the carriage and mounted again, it is difficult to maintain an accurate value unless the data is continuously held in the apparatus main body. However, even if it is held in the apparatus main body, the ink remaining amount cannot be updated when used in another apparatus.

On the other hand, no matter what device is used, if the remaining ink data is written to the print head itself when the remaining ink in the print head changes, the print head can be replaced. In addition, the ink remaining amount data can be read from the newly installed print head.

Specifically, immediately after the ink has been consumed by the printing process, head cleaning, etc., the value obtained by subtracting the consumed dot count value from the current ink amount in the print head is calculated as a new ink remaining amount in the print head. The magnetic tape 12 on the print head 101 through the magnetic head 120
Write to 2. On the other hand, when the power is turned on and the print head is replaced, the magnetic tape 1 on the print head passes through the magnetic head.
By reading the remaining ink amount in the print head from the print head 22, even when the print head 101 is replaced, the remaining ink amount can be recognized without being erroneously detected. By performing print control suitable for the recognized state of the print head, it is possible to perform printing in consideration of, for example, the amount of ink in the head and the ejection characteristics between the heads. Further, the remaining amount of ink can be displayed on the operation panel 111 automatically after the detection or in accordance with an instruction of the operator, or can be printed out on the printing paper 102.

Of course, if the storage capacity of the magnetic tape 122 permits, parameters other than the ink remaining amount data are also stored on the magnetic tape 1.
22 can be stored together.

While the preferred embodiment of the present invention has been described above, various modifications and changes can be made without departing from the scope of the claims. For example, a plurality of tracks may be recorded on a magnetic tape. Further, the example of the ink jet system has been described, but the present invention can be applied to an image forming apparatus of another system, for example, a thermal transfer system. The dynamic data in that case is, for example, the remaining amount of the ink ribbon, and the magnetic tape can be attached to the ink tape cartridge.

[0032]

According to the present invention, an externally readable and writable magnetic recording medium is provided to each print head so that print attribute data can be written to the print head itself. However, at the time of reattachment, data can be read from the magnetic recording medium on the print head to recognize the current state of the print head. In addition, since writing and reading of the magnetic recording medium can be performed with the movement of the carriage, the number of additional components required for the present invention can be minimized.

[Brief description of the drawings]

FIG. 1 is a view showing a schematic configuration of a serial printer type inkjet image forming apparatus according to the present invention.

FIG. 2 is a view of the carriage 106 of FIG. 1 as viewed from behind.

FIG. 3 is a block diagram illustrating a configuration of control hardware of the image forming apparatus according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 101 print head 102 print paper 103 sub-scanning motor 104 transport roller 105 main scanning motor 106 carriage 107 main scanning belt 108 home position (HP) sensor 109 linear scale 120 magnetic head 122 magnetic tape 123 linear scale sensor 209 write / read control unit

Claims (3)

[Claims] 1. An image forming apparatus having at least one print head, a carriage on which the print head is mounted, carriage driving means for reciprocating the carriage in one direction, and at least a print operation of the print head. Means for monitoring print attribute data that changes by changing the position of the print head, and magnetic recording means for writing and reading the print attribute data with respect to a magnetic recording medium provided to the print head as the carriage moves. An image forming apparatus comprising: 2. The image forming apparatus according to claim 1, wherein the print head is an ink jet head, and the print attribute data that changes with the printing operation is data relating to the remaining amount of ink. 3. The printing method according to claim 1, wherein the print attribute data is written to the recording medium at least after a printing process is completed, and is read from the magnetic recording medium when the print head is replaced and when the apparatus is turned on. 3. The image forming apparatus according to 2.