JP2931386B2 - Ink jet recording apparatus and method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus and method for performing recording by discharging ink from a discharge port to a recording medium, and more particularly, to shortening a recording time by improving throughput. The present invention relates to an ink jet recording apparatus and method for shortening the time.

[Prior Art] Conventionally, an ink jet recording apparatus performs recording of characters or images by discharging ink toward a recording medium from a discharge port using ink of one color or a plurality of colors. This is a feature not found in other recording devices, in that it can perform high-quality images with noise and can record information in a non-contact manner for many types without selecting the material of the recording medium.

By the way, since the ink jet recording apparatus uses liquid ink, if the recording head is discharged while the recording head is placed at the recording position, the rear end of the recording medium comes into contact with the ink ejection port of the recording head, and the recording medium is discharged. There is a possibility that the ink becomes dirty. Therefore, conventionally, when a recording medium on which recording has been completed is to be discharged to the outside of the apparatus, the recording head is temporarily moved to a predetermined retracted position (for example, a home position), and then conveyance for discharging is started. Was like that.

Further, in the conventional ink jet recording apparatus, similarly to other types of recording apparatuses, the paper feeding operation is started after the paper discharging operation is completed at the time of paper discharging.

[Problems to be Solved by the Invention] However, as described above, in the conventional ink jet recording apparatus, the movement for retracting the recording head and the paper discharging operation are separately performed, and the paper discharging operation and the paper feeding operation are performed separately. Since these operations were performed separately, it took time to discharge and feed the paper, and the high-speed recording performance of the apparatus could not be fully utilized.

In view of the above, an object of the present invention is to prevent the recording medium from being stained by ink, to improve the throughput by shortening the time of paper ejection and paper feeding, and to substantially reduce the recording time. To provide an ink jet recording apparatus and method.

[Means for Solving the Problems] To achieve the above object, an invention of an ink jet recording apparatus according to claim 1 performs recording on the recording medium using a recording head that discharges ink from a discharge port to the recording medium. In the ink jet recording apparatus, a head moving unit that reciprocates the recording head in the main scanning direction, a feeding unit that feeds a recording medium, a discharging unit that discharges the recording medium, and feeding by the feeding unit. Detecting means for detecting a leading end or a trailing end of the recording medium, feed amount counting means for counting a feed amount of the recording medium at least according to a detection output of the detecting means or a feed start command, and the feed amount Determining means for determining whether or not the rear end of the recording medium has reached a predetermined prohibited area based on the feed amount obtained from the counting means; Control means for driving the head moving means and the ejecting means together in response to an affirmative determination that the recording medium is not reached, thereby performing drive control for ejecting the recording medium while retracting the recording head to a predetermined position. It is characterized by having.

Here, preferably, the control means moves the recording head to a predetermined position by sequentially operating the head moving means and the ejection means in response to a negative determination that the determination means has reached the prohibited area. The drive control for unloading the recording medium after the retraction is performed.

Preferably, the determining means determines that the rear end of the recording medium has not reached a predetermined prohibited area when the rear end of the recording medium is prevented from being lifted up by a pressing member. When the trailing edge of the recording medium has come out of the pressing member, it is determined that the recording medium has reached the prohibited area.

Preferably, the recording head has an electrothermal converter as an element for generating energy for discharging the ink, for applying thermal energy for causing film boiling of the ink.

Preferably, the determining unit determines whether or not the rear end of the recording medium has reached a predetermined allowable area based on a rear end detection signal obtained from the detecting unit. By driving the head moving means to retract the recording head to a predetermined position in response to an affirmative judgment that the judgment means has reached the allowable area, by operating both the discharging means and the feeding means together Driving control for feeding and discharging the recording medium is performed.

In order to achieve the above object, the invention of an ink jet recording method according to claim 6, wherein the recording head is an ink jet recording method for performing recording on the recording medium by using a recording head that discharges ink from a discharge port to the recording medium. Head moving means for reciprocating the recording medium in the main scanning direction, feeding means for feeding the recording medium, discharging means for discharging the recording medium, and the front or rear of the recording medium fed by the feeding means. Detecting means for detecting an end of the recording medium, counting a feed amount of the recording medium at least according to a detection output of the detecting means or a feed start instruction, and determining a rear end of the recording medium based on the feed amount to a predetermined value. It is determined whether or not the area has not reached the prohibited area, and the head moving means and the ejecting means are operated together in response to an affirmative determination that the area has not yet reached the prohibited area. And performing drive control for unloading the recording medium while retracting said recording head to a predetermined position.

[Operation] In the present invention, the feeding amount of the recording medium is measured at least in accordance with the detection output of the detecting means for detecting the leading end or the trailing end of the recording medium or the feed start command, and the recording medium is measured based on the feeding amount. It is determined whether or not the rear end of the recording head has reached the predetermined prohibited area, and in response to an affirmative determination that the rear end has not yet reached the prohibited area, the recording head is operated by operating both the head moving means and the discharging means. The drive control for ejecting the recording medium while retracting the recording medium to a predetermined position is performed, so that the recording medium can be prevented from being stained with ink, the discharge time can be shortened to improve the throughput, and the recording time can be substantially reduced. The target shortening is obtained.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a basic configuration of an embodiment of the present invention. In the figure, reference numeral A denotes a head moving unit that reciprocates a recording head that discharges ink from a discharge port onto a recording medium in the main scanning direction. B is a feeding means for feeding the recording medium.
C is a discharging means for discharging the recording medium. D is a detecting means for detecting the leading end or the trailing end of the recording medium being fed by the feeding means B. E is a feed amount counting unit that counts the feed amount of the recording medium by using a detection output of the detection unit D or a paper feed start command as a trigger signal. F is feed amount counting means E
Is a determining means for determining whether or not the rear end of the recording medium has reached a predetermined prohibited area based on the feed amount obtained from the step (a). G moves the recording head to a predetermined position by simultaneously operating the head moving means A and the ejecting means C in response to an affirmative judgment that the judging means E has not yet reached the prohibited area, and simultaneously ejects the recording medium. This is control means for performing drive control. Further, as an example, the control unit G retreats the recording head to a predetermined position by sequentially operating the head moving unit A and the ejection unit C in response to a negative determination that the determination unit E has reached the prohibited area. Then, drive control for unloading the recording medium is performed.

In another aspect, the determination unit F determines whether the rear end of the recording medium has reached a predetermined allowable area based on the rear end detection signal obtained from the detection unit D. Then, the control means G controls the drive control for simultaneously feeding and discharging the recording medium by simultaneously operating the discharge means C and the feed means B in response to an affirmative determination that the determination means F has reached the allowable area. Do.

Further, as a specific example, when the rear end of the recording medium is prevented from being lifted by the pressing member, the determination unit F determines that the rear end of the recording medium has not reached the predetermined prohibited area, When the rear end has escaped from the pressing member, it is determined that the prohibited area has been reached. Alternatively, the determining means F determines whether or not the rear end of the recording medium has reached a predetermined allowable area based on the trailing edge detection signal obtained from the detecting means D. In response to an affirmative determination that the recording medium has reached the allowable area, the head moving means A is driven to retract the recording head to a predetermined position, and then the discharging means C and the feeding means B are simultaneously operated to feed the recording medium. And discharge at the same time.

The permissible area is set, for example, according to the distance between the feeding means B and the recording head.

FIG. 2 shows an example of the structure of a so-called bubble jet (BJ) type color ink jet recording apparatus having an electrothermal converter as a discharge energy generating means as a preferred embodiment of the present invention.

In FIG. 2, a recording medium 1 such as a sheet of paper or a plastic sheet is placed on a sheet feeding tray 2 and driven by a sheet feeding LF (line feed) motor (see FIG. 5) described later. Paper is fed one by one by 3
Further, the paper is conveyed to the ink jet recording head 6 while being synchronized by a pinch roller 4 and a paper feed roller (also referred to as a conveyance roller) 5. A PE (paper end) sensor lever 7 is provided near the upstream side of the pinch roller 4. When the leading end of the recording medium 1 pushes down the PE sensor lever 7, the PE photo sensor 8 at the lower end of the PE sensor lever 7 is activated. When the recording medium 1 is turned on and the rear end of the recording medium 1 passes through the PE sensor lever 7, the PE sensor lever 7 returns to its original state,
The photo sensor 8 is turned off. An optical reflection type paper width sensor 9 for detecting the lateral size (dimension) of the recording medium 1 is provided near the ink ejection port of the recording head 6, and the recording medium 1 passes through the paper width sensor 9. Thus, the actual paper width size of the recording medium 1 is detected. Reference numeral 10 denotes a paper presser plate spring for preventing the recording medium 1 from rising, and is disposed near the recording head 6 from upstream to downstream of the pinch roller 4. A guide shaft 11 is provided in front of the pinch roller 4 and the paper feed roller 5 so as to be parallel thereto.
Is provided. The carriage 12 is reciprocated along the guide shaft 11 via a wire (not shown) by the output of a carriage motor (see FIG. 5).

The recording head unit 6 which is a BJ type inkjet head is mounted on the carriage 12. The recording head unit 6 is for color image creation, is arranged in the scanning direction, and is provided corresponding to each color ink of cyan (C), magenta (M), yellow (Y), and black (BK). Consists of a number of recording heads. A plurality of (e.g., eight) ink ejection ports are vertically arranged on a surface of each recording head facing the recording medium 1 at a predetermined interval (e.g., 0.8 mm).
Recording units arranged in rows are provided.

A plurality of ink ejection ports are formed at a predetermined pitch in the vertical direction on the surface of the recording head 6 facing the recording medium 1, and an electrothermal converter (heating resistor) of each ink ejection port is formed based on recording information. Is driven (electrically heated) to generate bubbles (bubbles) in the ink, a flying ink droplet is formed by the pressure at this time, and recording is performed while ink dots adhere to the recording medium 1 in a predetermined pattern. A circuit board of a driving circuit (driver) for driving in this manner is mounted on each recording head.

Further, a control unit including a control circuit (CPU) of the recording apparatus and a ROM, a RAM, and the like attached to the control unit are formed on a control board (not shown). (Not shown), a driving signal (heat voltage) for the electrothermal transducer is supplied to each recording head 6 via a heat driver together with driving sources for various motors and the like based on the command signal and data signal (recording information). Is applied.

The carriage 12 is provided with a cartridge lever 13 for adjusting the distance between the recording head 6 and the recording medium 1. The lever 13 is moved from a solid line position to a broken line position in FIG.
Alternatively, by changing from a broken line position to a solid line position, the sheet distance changes. Thereby, it is possible to cope with the recording medium 1 having a relatively large thickness. Recording head 6
Are supplied from ink tanks 14 for respective colors provided at the lower part of the apparatus.

FIG. 3 shows the structure in the vicinity of the recording head 6 of FIG. 2 in detail. Here, reference numeral 15 denotes a platen that forms a conveyance path, and 16 denotes a paper discharge roller provided on the conveyance path on the downstream side of the recording head 6. The recording medium 1 is conveyed by a pinch roller 4 and a paper feed roller 5, and information such as a character image is recorded on a platen 15 by ink ejected from a recording head 6. (See Fig. 4).

FIGS. 4 (A) and 4 (B) show the entire appearance of the ink jet recording apparatus of FIG. 2. In particular, FIG. 4 (B) shows the position of the ink tank 14 by opening the lower front cover 17 of the apparatus. Things. In FIG. 4, reference numeral 18 denotes a discharge tray, and reference numeral 19 denotes an operation panel. The operation panel 19 attached to the outer case of the recording apparatus includes a key setting portion such as an online / offline switching key, a line feed key, a form feed key, a recording mode switching key, and some alarm lamps and a power lamp. And the like, and a display unit 20 including a warning lamp.

FIG. 5 shows a configuration example of a control system of the BJ type ink jet recording apparatus of FIG.

In FIG. 5, a CPU 21 in the form of a microprocessor is shown.
Are connected to a host device 41 such as a computer via an interface 22, and read from the host device 31 into a data memory 23, a recording information signal, a program memory 24 in the form of a ROM, and a working memory. The recording operation is controlled based on programs and data as shown in FIG. 7 or FIG. A PE photo sensor (referred to as a sheet sensor) 8 detects whether or not the recording medium 1 exists between the paper feed roller 3 and the paper feed roller 5 (FIG. 2).
The detection signal is transmitted to CPU 21.

The output from each of the operation keys 42 on the operation panel 19 described above is transmitted to the CPU 21 through the input port 27.
A control signal is supplied to 20 via an output port 28.

From the power supply circuit 29, a logic drive voltage VCC (5V) for operating the control logic circuit, various motor drive voltages V
M (30 V), reset voltage RESET, heat voltage (head voltage) VH (25 V) for heating the dot forming element (electrothermal transducer) of each recording head 6, and backup voltage VDDH for protecting the recording head 6 Is output. The heating voltage VH is applied to the recording head 6, and the backup voltage VDDH is applied to the head control circuit 30 and the recording head 6, respectively.

Further, the CPU 21 is connected to the driver circuit 32 through the output port 31.
The driver circuit 32 is connected to the paper feed roller 3, the paper feed roller 5, and the paper discharge roller 16 based on a control signal (command) supplied from the CPU 21 through the output port 31.
And a load such as an LF motor 33 for rotating the motor, a clutch 34, and a carriage motor 35 for reciprocating the carriage 12. In particular, the driver circuit 32 of this example can change the rotation speed and torque of the LF motor 33 by variably controlling the output pulse interval (frequency).
Can change the direction of rotation.

Hereinafter, an operation example of the color inkjet recording apparatus according to the present embodiment will be described with reference to FIGS. 6 and 7. FIG.

In the present embodiment, if the rear end of the recording medium 1 does not exist at a predetermined prohibited area position at the time of paper ejection,
The retracting operation of the recording head 6 and the paper feeding operation for discharging the paper are performed at the same time. FIG. 6 shows an example of the positional relationship between the recording medium 1 and this prohibited area. When the recording head 6 is located within the area indicated by the reference numeral AA in FIG. 6 with respect to the recording medium 1 when the paper ejection command is issued, it is determined that the rear end of the recording medium 1 does not exist in the prohibited area indicated by hatching. When the print head 6 is located in the prohibited area, the retracting operation and the paper feeding operation are performed simultaneously. Execute The XX line in this figure indicates the boundary position of the area.

When the retreat operation of the recording head and the paper feeding operation are performed at the same time, the rear end of the recording medium 1 is moved when the recording head 6 arrives at the retreat position in order to prevent the recording medium 1 from coming into contact with the ink ejection port. Pinch roller 6 or paper press leaf spring
It must be still sandwiched between 10. Considering this, the length of L1 of the prohibited area along the paper feed direction indicated by the arrow is determined by the paper feed speed (recording medium conveyance speed) and the carriage.
12 based on the moving speed (return speed) of the recording medium 1 to the retracted position and the distance between the paper holding plate spring 10 or the pinch roller 4 and the ink discharge position of the recording head 6, and the like.
It is predetermined.

Next, a control procedure in this embodiment will be described. As shown in FIG. 7, first, it is determined whether or not one paper feed amount of the recording medium is within AA in FIG. 6 (step S1). That is, as described above, whether the recording head 6 is within the area indicated by the reference numeral AA in FIG. 6 on the recording medium 1 (in other words, when the recording head 6 is at the position of the line XX). It is determined whether or not the rear end of the medium 1 is in the prohibited area indicated by hatching by comparing the count value of the paper feed amount of the internal counter of the CPU 21 with a predetermined set value. This set value is determined based on the length (paper size) of the recording medium 1 in the transport direction and the length L1 of the above-described prohibited area in the feed direction. The internal counter is triggered by the rising edge of the ON signal of the PE photosensor 8 and starts counting the paper feed amount.
The count is executed in synchronization with the drive pulse of the motor 33.
Note that, for example, a paper feed command signal is also effective as the trigger signal.

If the determination in step S1 is affirmative (YES), it is next determined whether or not a sheet discharge command, that is, an FF (home feed) signal has been generated (step S2). When the determination is affirmative, the process proceeds to the sheet discharging operation.
It is confirmed that the rear end of the print head 6 does not exist in the forbidden area indicated by hatching in FIG. 6, so that the carriage motor 35 and the LF motor 33 are simultaneously driven to retract the printhead 6 (C
R) and a paper feed operation (LF) for discharging the recording medium 1 are performed simultaneously (step S3). As a result, the paper discharge time is greatly reduced. Further, by properly setting the prohibited area, it is guaranteed that the rear end of the recording medium 1 is still caught by the pinch roller 6 or the paper pressing leaf spring 10 when the recording head 6 arrives at the retracted position. Therefore, even if the above two operations are performed at the same time, the ink is not stained. When the FF signal is not generated, the normal recording operation is continued.

On the other hand, when a negative determination (NO) is made in step S1, that is, when the paper feed amount is not within the predetermined AA and reaches the prohibited area, the carriage motor 35 is first driven by driving the carriage motor 35 to prevent the occurrence of ink contamination. After the retraction operation (CR) of Step 6 is completed (Step S4), the LF motor 33 is driven to perform the paper feed / discharge operation (LF) of the recording medium 1 (Step S5). Therefore, according to the present embodiment, the occurrence of ink contamination is always prevented.

8 and 9 show the operation of the second embodiment of the present invention.

In the present embodiment, it is determined whether or not the rear end of the recording medium 1 has reached a predetermined allowable area based on the position detection signal of the recording medium 1. The paper is discharged at the same time. FIG. 8 shows an example of the positional relationship between the recording medium 1 and this allowable area. When the recording head 6 is located within the hatched area indicated by reference numeral BB in FIG. 8 with respect to the recording medium 1 when the discharge command is issued, the recording medium 1
The paper feed operation and the paper discharge operation of the recording medium 1 are performed at the same time assuming that the rear end of the print medium has reached the allowable area. The YY line in this figure indicates the boundary position of the area, and the part above the YY line is a prohibited area that prohibits simultaneous execution of the above two operations when the recording head 6 is located in this part.

When performing the paper discharging operation and the paper feeding operation at the same time, in order to prevent the two recording media 1 from coming into contact with each other during paper feeding,
The length of L2 of the permissible area along the paper feed direction indicated by the arrow is based on the distance between the recording head 6 and the pinch roller 4 (or the PE sensor lever 7), and if necessary, the feed roller 3 and the pinch roller. 4 (or the PE sensor lever 7) is determined in advance in consideration of the distance.

FIG. 9 shows a control procedure of the sheet feeding / discharging operation according to the second embodiment of the present invention.

First, while the paper feed operation is performed by driving the LF motor 33 according to the recording signal (step S11), it is determined whether or not the rear end of the recording medium 1 is detected by the PE photo sensor 8 (step S12). FF signal (discharge command)
It is determined whether or not has occurred (step S13). When steps S12 and S13 are negative, the process returns to step S11,
When the determination in step S13 is affirmative, in order to prevent the occurrence of ink contamination, first, after the retraction operation (CR) of driving the carriage motor 35 to move the recording head 6 to the rightmost home position is completed (step S14), O clutch 34
N, the LF motor 33 is driven to simultaneously perform the paper feeding and discharging operation and the paper feeding operation of the recording medium 1 (step S15).

In the above-described embodiment, an example is shown in which both the paper feed and the paper discharge are performed by one LF motor (paper feed motor) 33. However, the paper feed motor and the paper discharge motor may be separately provided and controlled. Further, the first and second embodiments can be combined.

(Others) The present invention brings about an excellent effect particularly in a bubble jet type recording head and a recording apparatus proposed by Canon Inc. among ink jet recording methods. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

As for the representative configuration and principle, it is preferable to use the basic principle disclosed in, for example, US Pat. Nos. 4,723,129 and 4,740,796. This method can be applied to any of the so-called on-demand type and continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or liquid path holding the liquid (ink). Applying at least one drive signal corresponding to recording information and providing a rapid temperature rise exceeding nucleate boiling to the electrothermal transducer, thereby causing the electrothermal transducer to generate heat energy, and This is effective because a film in the liquid (ink) corresponding to the driving signal can be formed one by one by causing film boiling on the heat acting surface. 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. U.S. Pat. No. 44
Those described in JP-A-63359 and JP-A-4345262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the invention relating to the temperature rise rate of the heat acting surface are employed, more excellent recording can be performed.

As a configuration of the recording head, in addition to a combination configuration (a linear liquid flow path or a right-angled liquid flow path) of a discharge port, a liquid path, and an electrothermal converter as disclosed in the above-mentioned specifications, A configuration using U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, which disclose a configuration in which is disposed in a bending region, is also included in the present invention. In addition, Japanese Unexamined Patent 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 opening 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 with the serial type printer as in the above example, the recording head fixed to the main unit or attached to the main unit enables electrical connection with the main unit and supply of ink from the main unit. The present invention is also effective when a replaceable chip type print head or a cartridge type print head having an ink tank provided integrally with the print head itself is used.

Further, it is preferable to add recovery means for the print head, preliminary auxiliary means, and the like provided as a configuration of the printing apparatus in the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, capping means for the recording head, cleaning means, pressurizing or suction means, preheating means using an electrothermal transducer or another heating element or a combination thereof, Performing a preliminary ejection mode in which ejection is performed separately from printing is also effective for performing stable printing.

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

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink that solidifies at or below room temperature and softens or liquefies at room temperature, or the ink itself in an inkjet method. In general, the temperature is controlled 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. I just need. In addition, the temperature rise due to thermal energy can be positively prevented by using it as energy for changing the state of the ink from a solid state to a liquid state, or ink that solidifies in a standing state to prevent evaporation of the ink can be used. In any case, the ink is liquefied by the application of the thermal energy according to the recording signal, and the ink is liquefied, and the liquid ink is discharged. The present invention is also applicable to a case where an ink that liquefies for the first time by energy is used. The ink in such a case is disclosed in
No. -56847 or JP-A-60-71260, while being held as a liquid or solid substance in a porous sheet recess or through hole, facing the electrothermal converter. It is good also as a form. 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 may be used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, or a facsimile apparatus having a transmission / reception function. Or the like.

[Effects of the Invention] As described above, according to the present invention, the feeding amount of the recording medium is measured at least in accordance with the detection output of the detecting means for detecting the leading end or the trailing end of the recording medium or the feed start command. It is determined whether or not the rear end of the recording medium has not reached a predetermined prohibited area based on the feed amount, and in response to an affirmative determination that the rear end has not yet reached the prohibited area, the head moving means and the discharging means By operating both of them, the drive control for carrying out the recording medium while retracting the recording head to a predetermined position is performed, thereby preventing the recording medium from being stained with ink and shortening the time for discharging the paper. This has the effect of increasing the throughput and substantially reducing the recording time.

[Brief description of the drawings]

1 is a block diagram showing a basic configuration of an embodiment of the present invention, FIG. 2 is a cross-sectional view showing an example of an internal configuration of an ink jet recording apparatus according to an embodiment of the present invention, and FIG. 3 is a recording head of FIG. 4 (A) and 4 (B) are perspective views showing an overall appearance example of the ink jet recording apparatus of the embodiment of the present invention shown in FIG. 2, and FIG. FIG. 6 is a block diagram showing a circuit configuration of a control system of the apparatus shown in FIG. 6, FIG. 6 is an explanatory diagram showing a prohibited area according to an embodiment of the present invention, FIG. 7 is a flowchart showing a processing procedure according to an embodiment of the present invention; FIG. 8 is an explanatory diagram showing an allowable area according to another embodiment of the present invention, and FIG. 9 is a flowchart showing a processing procedure according to another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Recording medium, 2 ... Paper feed tray, 3 ... Paper feed roller, 4 ... Pinch roller, 5 ... Paper feed roller, 6 ... Recording head, 7 ... PE sensor lever, 8 ... PE Photo sensor, 9… Paper width sensor, 10… Paper holding plate spring, 11… Guide shaft, 12… Carriage, 20… Display unit, 21… CPU, 22… Data memory, 24… Program memory, 34 ... clutch, 35 ... carriage motor, 41 ... host device.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Makoto Takemura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Tetsuji Kurata 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Kazuhiko Shinoda 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Koichiro Kawaguchi 3-30-2, Shimomaruko, Ota-ku, Tokyo Canon Inc. ( 56) References JP-A-2-81658 (JP, A) JP-A-1-288471 (JP, A) JP-A-64-24776 (JP, A) JP-A-3-138250 (JP, A) (58) ) Field surveyed (Int. Cl. ⁶ , DB name) B41J 13/00 B41J 19/00

Claims (6)

(57) [Claims] 1. An ink jet recording apparatus that performs recording on a recording medium using a recording head that discharges ink from a discharge port to the recording medium, comprising: a head moving unit that reciprocates the recording head in a main scanning direction; Feeding means for feeding a recording medium; discharging means for discharging the recording medium; detecting means for detecting a leading end or a trailing end of the recording medium fed by the feeding means; Feed amount counting means for counting the feed amount of the recording medium in response to a detection output or a feed start command; and a rear end of the recording medium having a predetermined prohibited area based on the feed amount obtained from the feed amount counting means. The head moving means and the ejecting means are operated together in response to an affirmative determination by the determining means that the area has not yet reached the prohibited area. Control means for performing drive control for ejecting the recording medium while retracting the recording head to a predetermined position. 2. The control means retreats the recording head to a predetermined position by sequentially operating the head moving means and the ejection means in response to a negative judgment of the judgment means having reached the prohibited area. 2. The ink jet recording apparatus according to claim 1, wherein drive control for unloading the recording medium is performed after the recording. 3. The determination means determines that the rear end of the recording medium has not reached a predetermined prohibited area when the rear end of the recording medium is prevented from being lifted by a pressing member. 3. The ink jet recording apparatus according to claim 1, wherein when the trailing end of the recording medium is out of the pressing member, it is determined that the recording medium has reached the prohibited area. 4. 4. The recording head according to claim 1, further comprising an electrothermal transducer for applying thermal energy for causing film boiling of the ink, as an element for generating energy for discharging the ink. The inkjet recording apparatus according to claim 1. 5. The determination means determines whether or not the rear end of the recording medium has reached a predetermined allowable area based on a rear end detection signal obtained from the detection means. By driving the head moving means to retract the recording head to a predetermined position in response to an affirmative judgment that the judgment means has reached the allowable area, by operating both the discharging means and the feeding means together 4. The ink jet recording apparatus according to claim 3, wherein drive control is performed to feed and discharge the recording medium. 6. An ink jet recording method for performing recording on a recording medium using a recording head that discharges ink from a discharge port to the recording medium, comprising: a head moving unit that reciprocates the recording head in a main scanning direction; A feeding unit that feeds a recording medium; a discharging unit that discharges the recording medium; and a detecting unit that detects a leading end or a trailing end of the recording medium fed by the feeding unit. The feed amount of the recording medium is counted according to a detection output of a detecting unit or a feed start command, and it is determined whether or not the rear end of the recording medium has not reached a predetermined prohibited area based on the feed amount. By operating both the head moving means and the ejecting means in response to an affirmative determination that the recording medium has not yet reached the prohibited area, the recording medium is retracted to a predetermined position while the recording medium is retracted. An ink jet recording method comprising performing drive control for carrying out a body.