JP2002103723A - Recorder and recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a recorder and a recording method performing main scanning through use of a stepping motor in which the hitting position is prevented from being shifted among a plurality of heads without requiring any encoder. SOLUTION: An encoder signal corresponding to the moving position of a head unit, comprising a plurality of recording heads each arranged with a plurality of recording elements and arranged in a direction different from the arranging direction of the recording elements, is detected by moving the head unit in the arranging direction thereof at a constant speed, a reference trigger signal is generated based on the encoder signal, and its time interval is stored in a storage device (S1-S6). The time intervals are read out sequentially from the storage device and a print trigger is generated according to the time interval thus read out (S7-S15).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus and method, and more particularly to a printing apparatus having a head unit in which a plurality of print heads for performing printing by performing main scanning by an ink jet system are arranged with an offset, and the apparatus. And a recording method using the same.

[0002]

2. Description of the Related Art Generally, a stepping motor is used in a main scanning system for moving a head carriage for a raster scan type printer such as an ink jet recording apparatus, particularly for a relatively low-priced model. The reason for this is that open loop control, which is the greatest feature of the stepping motor, is possible.

[0003] By performing open loop control, compared to a system that controls the position of a head carriage by using a DC motor and an optical or magnetic encoder unit, the cost is lower and the control is higher. There is no need to perform complicated control such as DC servo.

Next, the operation when a stepping motor is used in the main scanning system of the ink jet recording apparatus will be considered. A case in which the motor is controlled to move the load to the target position in the shortest time will be specifically described with reference to, for example, FIG. The relationship between the target position (horizontal axis) and the speed (vertical axis) in the running characteristic curve shown in FIG. 6 also applies to an embodiment of the present invention described later.

As shown in FIG. 6, in a section B, the motor pulley of the main scanning system is rotated at the maximum speed. Therefore, when it is desired to drive the motor pulley in the shortest time, it is desirable to shorten the rising time in the section A. After driving the motor pulley in a predetermined direction,
The speed of the motor pulley is rapidly reduced in section C.
Thereafter, in order to perform high-precision positioning, as shown in a section D, it is desirable to set the motor pulley to the lowest speed and drive it at a low speed. It is well known that in a drive using a stepping motor, a traveling characteristic curve as shown in FIG. 6 can be arbitrarily set.

In such open loop control of the stepping motor, since the moving speed of the carriage in the section B is constant, the print trigger signal is generated at an interval of time t from the end of the ramp-up (inclined slope) in the section A. Then, printing for one column is performed according to the print trigger signal. In the example of FIG. 7, a print trigger signal is generated at 200 μsec intervals. As a result of driving the head carriage at a driving speed of 8.3 inch / sec in the section B, a printing resolution of 600 dpi in the main scanning direction can be obtained. .

[0007]

In the section B of FIG. 6, the stepping motor is rotating at a constant speed. However, the relationship between the actual moving distance of the carriage and the time is, for example, as shown in FIG. To some extent between the ink and the second ink. In FIG. 8, the first ink and the second ink are different color inks, and are ejected from separate heads having offsets. But,
Since the open loop control is performed, the print trigger signal is output at equal time intervals, and thus the ink landing position of the print result is shifted from the 600 dpi interval as shown in FIG.

[0008] The reason why such a phenomenon occurs is considered that the motor shaft or the motor pulley is not a perfect circle. For this reason, in the case of a one-dot printer system in which the stepping motor has a 96 step angle and one step angle of 600 dpi, a landing position shift occurs at intervals of 96 dots.

[0009] These deviations are of such a degree that they are not visually noticeable even when the printing result is viewed in the case of monochromatic printing using black ink or the like. However, since the respective color heads of the color printer are arranged on the carriage with a predetermined amount of offset set, the landing deviation appearing every 96 dots differs for each color.

In recent years, printers that output high-tone images using dark and light inks or high-resolution images in, for example, 1200 dpi in the main scanning direction have been increasing. In particular, when printing natural images such as photographs, Landing deviations appear remarkably as noise in the printing result.

In view of the above, the present invention provides a recording apparatus and a method for performing main scanning using a stepping motor, wherein the recording apparatus and the method can prevent a displacement of a landing position between a plurality of heads without providing an encoder. Aim.

[0012]

In order to achieve the above object, the invention of claim 1 provides a head unit in which a plurality of recording heads in which a plurality of recording elements are arranged are arranged in a direction different from the arrangement direction. In a printing apparatus that performs printing by discharging ink from the discharge ports of the plurality of printing elements and scanning a printing medium while moving in different directions, a stepping motor that moves the head unit under open loop control. A stepping motor in which a positive integer multiple of the number of steps is an offset of the distance between the plurality of recording heads, and control for controlling the scanning by the stepping motor by driving the plurality of recording heads in accordance with the offset. And a recording apparatus of a form including means.

According to a second aspect of the present invention, in the recording apparatus according to the first aspect, the control means preliminarily sets a value based on an encoder signal detected in accordance with a moving position of the head unit when the scanning is performed at a constant speed. Storage means for storing a time interval of the generated reference trigger signal; means for sequentially reading the time interval from the storage means; and print trigger generation means for generating a print trigger in accordance with the read time interval. This is an embodiment of a recording apparatus of the present invention.

According to a third aspect of the present invention, in the recording apparatus of the first or second aspect, the recording apparatus is configured such that the means for detecting the encoder signal is detachable.

According to a fourth aspect of the present invention, in the recording apparatus of any one of the first to third aspects, a recording apparatus in which inks of different colors are ejected from ejection ports of the plurality of recording heads.

According to a fifth aspect of the present invention, in the recording apparatus according to the fourth aspect, the plurality of recording elements are provided with an electric-to-heat converting means, and the heat energy by the electric-to-heat converting means is applied to the ink. The device was implemented.

According to a sixth aspect of the present invention, there is provided a stepping motor for moving a head unit, in which a plurality of recording heads in which a plurality of recording elements are arranged in a direction different from the arrangement direction, are moved by open loop control. Using a stepping motor in which a positive integer multiple of the number of steps is offset by the distance between the plurality of recording heads, ink is ejected from the ejection openings of the plurality of recording elements while being moved in the different direction to perform recording. In a printing method for performing printing by scanning a medium, a printing method of a mode including a control step of controlling the scanning by the stepping motor by driving the plurality of printing heads according to the offset is performed. is there.

According to a seventh aspect of the present invention, in the recording method according to the sixth aspect, the control step includes a step of causing the scanning to be performed at a constant speed and detecting an encoder signal corresponding to a moving position of the head unit. Generating a reference trigger signal based on the encoder signal, storing the time interval in a storage device, sequentially reading the time interval from the storage device, and generating a print trigger according to the read time interval And a print trigger generating step.

According to an eighth aspect of the present invention, in the recording method of the sixth or seventh aspect, the detecting step is performed by mounting the means for detecting the encoder signal.

According to a ninth aspect of the present invention, in the recording method of any one of the sixth to eighth aspects, a recording method in which inks of different colors are ejected from the ejection openings of the plurality of recording heads.

According to a tenth aspect of the present invention, in the recording method according to the ninth aspect, the plurality of recording elements having an electric-to-heat converting means are used, and the thermal energy by the electric-to-heat converting means is applied to the ink. And a recording method characterized by the following.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an ink jet recording apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic perspective view of a printer apparatus having a recording head for performing recording according to an ink-jet system, which is a typical embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes recording paper (or various sheet-like recording media such as plastic sheets), and reference numerals 2 and 3 denote conveying rollers arranged upstream and downstream of a recording area of the recording paper 1. Recording paper 1 in the direction of arrow A
Is driven to rotate in the direction of transporting. 4 is a transport roller 2,
3 is a sheet feed motor, and 5 is transport rollers 2 and 3
Between the transport rollers 2,
3 is provided in parallel with the rotation axis.

Reference numeral 6 denotes a head carriage, which is guided by the guide shaft 5 and reciprocates in the double-headed arrow B direction. The moving position is detected by an encoder unit (not shown) detachably attached to the printer device. Reference numeral 7 denotes a carriage motor for moving the head carriage 6, and reference numeral 8 denotes a belt for transmitting the driving force of the carriage motor 7 to the head carriage 6. A motor pulley is mounted on the rotation shaft of the carriage motor 7.

On the head carriage 6, recording heads 9A to 9D (hereinafter, referred to as 4) for ejecting ink droplets and performing recording in accordance with an ink jet system using a heater.
When one recording head is referred to collectively, it is referred to as a recording head 9). The recording head 9 is for recording a color image, and is arranged in the moving direction of the head carriage 6 corresponding to each color ink of cyan (C), magenta (M), yellow (Y) and black (Bk). It comprises a recording head (K head) 9A, a recording head (C head) 9B, a recording head (M head) 9C, and a recording head (Y head) 9D.

On the surface of each of the recording heads 9A to 9D, that is, the surface facing the recording surface of the recording paper 1 at a predetermined interval, a plurality of (for example, in the direction substantially orthogonal to the scanning direction B of the head carriage 6). The 128 ink ejection ports (not shown) corresponding to the (128) recording elements (recording elements) are arranged in a substantially linear line. The logic circuits for driving the heaters of the recording elements of the recording heads 9A to 9D at a predetermined timing have the same configuration.

An operation panel 64 is attached to an outer case (not shown) of the printer. The operation panel 64 has an online / offline switching key 6
0A, line feed key 60B, recording mode switching key 60C, reset key 60D, other key setting sections, LE
D, etc., warning lamps such as an alarm lamp 61A and a power lamp 61B, and an LCD for displaying various messages
(Liquid Crystal Display) 6
5 are provided.

Reference numeral 91 denotes an ink tank for storing ink for recording a desired image on the recording paper 1. The ink tanks 91 include four ink tanks 91 for storing ink for each of cyan (C), magenta (M), yellow (Y), and black (Bk) corresponding to the recording heads 9A to 9D.
A to 91D.

As will be described in detail below with reference to the accompanying drawings, a control unit including a CPU of the printer device and a ROM, a RAM and the like attached to the printer device receives command signals and data signals (recording) from a host computer (hereinafter referred to as a host device) 100. Information), drives various motors and the like based on the received information, and applies a driving power supply (heat power supply) to the electrothermal transducers (heaters) of the recording elements of the recording heads 9A to 9D at a predetermined timing. And energize.

FIG. 2 is a block diagram showing a schematic configuration of a control circuit of the printer shown in FIG.

The CPU 21 in the form of a microprocessor comprises:
A ROM 24 that is connected to the host device 100 via the interface 22 and stores a control program, and an EEPROM 2 as a data memory that stores an updatable control program, a processing program, various constant data, and the like.
3, and from the host device 100 to the interface 22
The RAM 25 serving as a working memory for storing a command signal (command) and a recording information signal received via the RAM is accessed, and the recording operation is controlled based on the information stored in these memories.

The CPU 21 moves the head carriage 6 by rotating the carriage motor 7 via the output port 26 and the carriage motor control circuit 42, and moves the head port 6 and the sheet feed motor control circuit 4
The transport mechanism such as the transport rollers 2 and 3 is operated by rotationally driving the sheet feed motor 4 through the transport motor 4. Further, the CPU 21 controls the printhead 9 via the printhead control circuit 29 based on the print information stored in the RAM 25.
By driving A to 9D, a desired color image can be recorded on the recording paper 1.

Instructions input from the operation keys 60A to 60D are transmitted to the CPU 2 via the input port 32 and the CPU bus 70.
It is conveyed to 1. The command from CPU 21 is output port 3
The message is transmitted to the operation panel 64 via the LCD 6 and a message is displayed on the LCD 65 according to the instruction, and the alarm lamp 61A and the power lamp 61B are turned on.

From the power supply circuit 28, a logic drive voltage Vcc (for example, 5V) for operating the CPU 21, various motor drive voltages VM (for example, 30V), the recording head 9 are provided.
A heating voltage VH (for example, 25 V) for operating the
Further, a voltage VDDH for operating the print head control circuit 29 for controlling the print head 9 is output. CPU
The bus 70 connects the various components described above to each other to exchange data and commands.

FIG. 3 is a block diagram showing a schematic configuration of a main part of the present embodiment. In FIG. 3, reference numeral 107 denotes a sensor unit of the encoder described above, which is mounted before shipment from the factory and used for measuring and writing a trigger interval, and is removed at the time of shipment from the factory. Reference numeral 101 denotes a trigger generation circuit that generates a trigger signal from the edge of a rectangular wave captured from the sensor unit 107. The other elements in FIG. 3 are included in the print head control circuit 29 (FIG. 2), and the print trigger signal from the print trigger generation circuit 106 is used as a timing signal in the control circuit. The factory shipment mode switching signal to the print trigger generation circuit 106 is supplied by operating an operation key on the operation panel 64.

FIG. 4 is a flowchart showing the flow of processing according to this embodiment. FIG. 5 is a timing chart of a process of measuring the trigger signal interval generated from the encoder signal by the encoder trigger interval measurement counter 102 in FIG. Hereinafter, the characteristic operation of the present embodiment will be described with reference to FIGS. 3 to 5 and FIG.

When a pulse necessary for ramp-up in section A of FIG. 6 is transmitted, the CPU 21 determines in FIG. 4 that the ramp-up is completed and the head carriage 6 starts to move at a constant speed in section B (S1). A trigger generation start signal is output (S2). Subsequently, in step S3, it is determined whether or not the mode is the factory shipping mode.

At the time of setting before shipment from the factory, the recording mode is set to the factory shipment mode by a key operation. Therefore, a trigger generation start signal is input to the encoder trigger interval measurement counter 102 and the encoder trigger interval measurement counter 102 Is the trigger output start signal and the trigger generation circuit 1
First, the trigger interval T0 generated in step 01 is measured (S
4). The measured value T0 is the interval T1 until the next trigger
During the measurement of DRA by the DMA controller 104.
It is written to M23 (S5).

In the constant speed moving section B, the trigger interval T
Appear repeatedly at the step number N of the stepping motor. Therefore, a loop process for measuring the trigger interval T N times is executed based on the determination in step S6. In this loop processing, counting of the number of triggers is performed by the encoder trigger counter 103, and steps S4 to S6 are repeated until measurement and writing are performed N times. When the above processing is completed, the factory shipping mode is released by key operation, and the printer is shipped in the released state.

When printing is performed using the shipped printer device, steps S1 and S2 are performed in the same manner, and in step S3 it is determined that the mode is not the factory shipping mode, and the printer is used in the normal printing mode. The processing after step S7 is executed.

That is, the data latch 105 has a CPU
The value of T0 read from the DRAM 23 via the data bus 70 is held, and the held value T0 is latched by the data latch 108 by the trigger generation start signal (S7). The print trigger generation circuit 106 starts the counting operation of the internal counter in response to the trigger generation start signal, and outputs a print trigger after the lapse of time T0 to clear the counter (S8).

Subsequently, after the counter value A is incremented and counted by the print trigger counter 109 (S9), a preset print trigger output number M and a counter value A are set.
Are compared (S10). The counter value A is the number of print triggers that have been output at the present time. When the counter value A matches the preset print trigger output number M (A = M), the process ends. If they do not match, the DMA controller 104 sends the next Tn (n = 1,
,...) Are read (S11), and the read values are latched by the data latch 105 (S12).

Here, the number of output print triggers is counted by the print trigger counter 110, and the counted value n is compared with the step number N of the stepping motor (S13). When the count value n matches the step number N of the stepping motor (n = N), n ← 1 is set (S
15), the print trigger counter 109 is cleared and the process returns to step S7. On the other hand, if n = N is not satisfied, the print trigger counter 109 counts up, and step S1 is executed.
In step 4, n ← (n + 1) is set and the process returns to step S7.

Thereafter, starting from the print trigger, steps S7 to S14 or steps S7 to S1 until A = M.
5 is repeated, and when A = M, the process is terminated.

(Others) It should be noted that the present invention includes a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for performing ink ejection, particularly in an ink jet recording system. An excellent effect is obtained in a recording head and a recording apparatus of a type in which the state of ink is changed by the thermal energy. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recorded information and giving a rapid temperature rise exceeding the nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal on a one-to-one basis.
This is effective because air bubbles inside can be formed. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, U.S. Pat. No. 4,558,333 and U.S. Pat. No. 44,558 which disclose a configuration in which a heat acting portion is arranged in a bending region.
A configuration using the specification of Japanese Patent No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an aperture for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head.

In addition, even in the case of the serial type as described above, a recording head fixed to the apparatus main body or an electric connection with the apparatus main body or ink from the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

Further, it is preferable to add ejection recovery means for the recording head, preliminary auxiliary means, and the like as the constitution of the recording apparatus of the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, the recording head is heated using capping means, cleaning means, pressurizing or suction means, an electrothermal transducer, another heating element or a combination thereof. Pre-heating means for performing the pre-heating and pre-discharging means for performing the discharging other than the recording can be used.

The type and number of recording heads to be mounted are not limited to those provided only for one color ink, for example, and for a plurality of inks having different recording colors and densities. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of the recording modes of full color by color mixture.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. In addition, in order to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the application of heat energy causes the ink to be liquefied by the application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start solidifying when it reaches the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, the ink
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent Publication No. 1260, it is also possible to adopt a form in which the sheet is opposed to the electrothermal converter in a state where it is held as a liquid or solid substance in the concave portion or through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, the form of the ink jet recording apparatus of the present invention is not limited to those used as image output terminals of information processing equipment such as computers, copying apparatuses combined with readers and the like, and facsimile apparatuses having a transmission / reception function. It may take a form.

[0055]

As described above, in a printing apparatus that performs printing on a printing medium by using a plurality of printing heads having a plurality of printing elements, the number of steps for each color head is N times the number of steps of the main scanning drive stepping motor. By giving the offset of the inter-distance, it is possible to suppress the landing variation generated for each head due to the influence of the motor shaft or the pulley of the stepping motor.

The sensor unit of the encoder is detachable, the encoder unit is mounted only at the time of product shipment at a factory, an encoder signal is input from outside the printer, and the time of the trigger signal interval generated by the encoder signal is set. By measuring T and sequentially writing it to the storage device, the time interval T written to the storage device can be sequentially read at the time of actual printing, and a print trigger can be generated at the read time interval. Thus, in an inkjet recording apparatus having no encoder, even in open loop control using a stepping motor, DC
There is an effect that the landing position control in the main scanning direction can be performed between a plurality of heads, which is equivalent to a recording apparatus using a motor and an encoder.

[Brief description of the drawings]

FIG. 1 is an external perspective view illustrating a configuration of an inkjet recording apparatus that is a typical embodiment of the present invention.

FIG. 2 is a block diagram illustrating a schematic configuration of a control circuit of the inkjet recording apparatus according to the present invention.

FIG. 3 is a main block diagram of an embodiment of an ink jet recording apparatus according to the present invention.

FIG. 4 is a flowchart showing an operation flow of the embodiment of the present invention.

FIG. 5 is a time chart illustrating an example of measurement by an encoder trigger interval measurement counter.

FIG. 6 is a characteristic diagram illustrating an example of a target position versus speed characteristic of a carriage.

FIG. 7 is an explanatory diagram showing an example of a print trigger and a landing position in a conventional example.

FIG. 8 is an explanatory diagram showing an example of a variation in landing positions in a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording medium 2, 3 Conveyance roller 4 Sheet feed motor 5 Guide shaft 6 Carriage 7 Carriage motor 8 Belt 9A Black recording head 9B Cyan recording head 9C Magenta recording head 9D Yellow recording head 21 CPU 22 Interface 23 Data memory (DRAM) 24 Program Memory (ROM) 25 Working memory (RAM) 26, 36 Output port 28 Power supply 29 Recording head control circuit 42 Carriage monitor control circuit 43 Transport mechanism 44 Sheet feed motor control circuit 11 45 A / D conversion circuit 61A Alarm lamp (error LED) 61B power lamp (power LED) 91 ink tank 91A black ink tank 91B cyan ink tank 91C magenta ink tank 91D yellow ink Link 100 the host computer 101 trigger generating circuit 102 encoder trigger interval measurement counter 103 encoder trigger counter 104 DMA controller 105 and 108 data latches 106 print trigger generating circuit 107 encoder sensor units 109, 110 print trigger counter

Claims (10)

[Claims] 1. A method of ejecting ink from ejection ports of a plurality of recording elements while moving a head unit having a plurality of recording elements arranged in a direction different from the arrangement direction and moving the head unit in the different direction. In a recording apparatus that performs recording by scanning a recording medium, a stepping motor that moves the head unit under open loop control, wherein a positive integer multiple of the number of steps is equal to the offset of the distance between the plurality of recording heads. A printing apparatus comprising: a stepping motor configured to drive the plurality of printing heads in accordance with the offset to control the scanning by the stepping motor. 2. The recording apparatus according to claim 1, wherein the control unit is configured to generate a reference based on an encoder signal detected in accordance with a moving position of the head unit when the scanning is performed at a constant speed. Storage means for storing a time interval of the trigger signal; means for sequentially reading the time interval from the storage means; and print trigger generation means for generating a print trigger in accordance with the read time interval. Recording device. 3. The recording apparatus according to claim 1, wherein the means for detecting the encoder signal is detachable. 4. The recording apparatus according to claim 1, wherein inks of different colors are ejected from ejection ports of the plurality of recording heads. 5. The recording apparatus according to claim 4, wherein the plurality of recording elements include an electric-to-heat converting unit, and apply heat energy from the electric-to-heat converting unit to the ink. 6. A stepping motor for moving a head unit in which a plurality of recording heads in which a plurality of recording elements are arranged in a direction different from the arrangement direction is controlled by open loop control, wherein the number of steps is Using a stepping motor in which a positive integer multiple of the distance between the plurality of recording heads is offset, and ejecting ink from the ejection openings of the plurality of recording elements to scan the recording medium while moving in the different directions. And a control step of driving the plurality of print heads in accordance with the offset to control the scanning by the stepping motor. 7. The recording method according to claim 6, wherein the control step comprises: causing the scanning to be performed at a constant speed to detect an encoder signal corresponding to a moving position of the head unit; Generating a trigger signal and storing the time interval in a storage device; sequentially reading the time interval from the storage device; and generating a print trigger in accordance with the read time interval. And a recording method comprising: 8. The recording method according to claim 6, wherein said detecting step is performed by mounting means for detecting said encoder signal. 9. The recording method according to claim 6, wherein inks of different colors are ejected from ejection ports of the plurality of recording heads. 10. The recording method according to claim 9, wherein the plurality of recording elements provided with an electric-heat conversion means are used,
A recording method, wherein heat energy by the electric-heat conversion means is applied to the ink.