JPH09188466A - Image recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of defective conveyance, such as a recording sheet being rolled on a discharge sheet loading means due to a curl occurring to the recording sheet and push out of a recording sheet precedingly discharged as a result of a subsequently discharged recording sheet making contact with the precedingly discharged recording sheet. SOLUTION: A paper sheet support member 10 is arranged in a position below and adjoining a discharge part 16 and the tip of a paper sheet P to be discharged is supported. When the paper sheet P is discharged to some extent, the paper sheet support member 10 is moved aside in a paper sheet conveying direction and the paper sheet P is dropped on a discharge stacker 15. After completion of discharge of the paper sheet P, the paper sheet support member 10 is positioned below and adjacent to the discharge part 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus equipped with a discharge sheet stacking unit for stacking recording sheets after image recording, and in particular, an ink jet system directly ejects ink onto the recording sheet. The present invention also relates to an image recording apparatus suitable for recording an image.

[0002]

2. Description of the Related Art On a recording sheet on which an image is recorded by an image recording apparatus, a phenomenon called curl in which the sheet itself is curved occurs due to various factors. In particular, in an image recording apparatus such as an ink jet system that directly ejects ink onto a recording sheet to record an image, the recording of the sheet after the image recording is affected by moisture or other components in the ink ejected onto the sheet. The surface expands and contracts, and the occurrence of curling is more noticeable than in other types of image recording apparatuses.

Since the conventional ink jet type image recording apparatus is mostly used for ejecting a small amount of ink onto a sheet so as to record only characters, curling occurs only to the extent that it does not pose a problem. I didn't. However, in recent years, full-color printing and high-speed printing have progressed, and it has become more frequent to print on the entire printing area with a printing head having a printing width larger than before, and the occurrence of curling becomes a major problem. Came.

Usually, the curl shape in an ink jet type image recording apparatus depends on the directionality of fibers generated at the stage of manufacturing a sheet, that is, what is called a so-called crevice. For example, if there is a gap A in the longitudinal and longitudinal directions of the sheet as shown in FIG. 8 (a), the direction of the gap A is usually a straight line as shown in FIG. Curls and curves, forming a curl.

Further, as shown in FIG. 9A, the sheet 51 immediately after recording is warped so that the recording surface is expanded by ejecting ink onto the recording surface 51a and the recording surface is located outside the curve. Make a curl. The sheet 51 left after that is shown in FIG.
As shown in (b), the recording surface of sheet 51
51a shrinks and warps so that the recording surface comes to the inside of the curve, resulting in a curl in the opposite direction to that immediately after printing. The change of the curl shape and the time required therefor are determined by various factors such as the environment and the recording state.

[0006] One of various adverse effects caused by the curl generated on the sheet is poor stackability on the discharge stacker after recording. The adverse effect on the discharge stacker caused by the curl is often related to the difference in height between the sheet discharge portion and the discharge stacker.

When it is attempted to stack a large number of sheets on the discharge stacker, the sheet discharge section and the discharge stacker must have a height difference corresponding to the number of sheets. Particularly in an image recording apparatus capable of high-speed recording, it is necessary to have at least the ability to stack the number of sheets that can be continuously recorded on the discharge stacker. However, as shown in FIG. 10, when the difference H in height between the sheet discharge portion and the discharge stacker is increased, the phenomenon that the sheet immediately after recording is rolled into a tubular shape often occurs on the discharge stacker. This phenomenon occurs most remarkably when the sheet is conveyed such that the gap direction of the sheet and the sheet conveying direction are perpendicular to each other and a large amount of ink is ejected onto the sheet 51.

Therefore, if the difference h in height between the sheet discharging portion and the discharging stacker is reduced on the assumption that the number of stacked sheets is reduced, the above-mentioned inconvenience does not occur. But for example the figure
As shown in 11 (a), when there is a gap perpendicular to the sheet conveying direction, the sheet 51c immediately after recording is curled so that the leading end and the trailing end are lowered due to the expansion of the recording surface. . On the other hand, the sheet 51b, which has been loaded on the discharge stacker 52 for a certain period of time, is curled so that the leading edge and the trailing edge of the sheet 51b are lifted by contraction of the recording surface. Therefore, when the newly-recorded sheet 51c is newly conveyed, the sheet 51c also slips under the already stacked sheet 51b.

Further, as shown in FIG. 11 (b), when there is a gap in the same direction as the sheet conveying direction, the recording surface of the sheet 51e immediately after recording is expanded so that the left and right ends of the sheet 51e are lowered. The sheet 51d is curled, but the sheet 51d that has been loaded earlier and has passed the time is curled so that the opposite ends are lifted up. Therefore, when the newly-recorded sheet 51e is conveyed, it comes into contact with the trailing end of the already-loaded sheet 51d and pushes it out from the discharge stacker.

Some of the measures taken by the conventional image recording apparatus against these phenomena are to maintain the height of the leading edge of the sheet by curving the sheet in the sheet discharging section so as to have a three-dimensional structure, and for the sheet discharging section. For example, there is one in which the sheet discharged from the sheet is once placed on a member that supports only both ends thereof, and after the sheet is completely discharged from the sheet discharging unit, the member is retracted and dropped and stacked on a discharge stacker.

[0011]

In any of the above methods, there are restrictions such as limiting the sheet skew direction with respect to the sheet conveying direction and the sheet size, and limiting the number of stacked stackers to a small number. By providing the sheet, it is possible to obtain the effect of stacking the sheets to some extent in a stable manner. However, in the future, if a large number of sheets are continuously recorded at high speed, or if recording with a large amount of ink that easily causes curl is continuously performed, the sheet conveying direction and the sheet size with respect to the sheet skew direction are randomly and continuously. It is considered that the number of cases recorded under various conditions will increase, such as when recording in. Therefore, correspondingly, an image recording apparatus capable of stacking a large number of sheets on the discharge stacker and causing no conveyance failure due to curl is required.

An object of the present invention is to solve the above-mentioned problems, and an object thereof is to provide an image recording apparatus provided with means for suitably stacking a large number of sheets after image recording on a discharge sheet stacking means.

[0013]

A typical configuration according to the present invention for achieving the above object is an image recording unit for recording an image on a recording sheet, a conveying unit for conveying the recording sheet, and an image recording unit. In an image recording apparatus having a discharging unit for discharging the discharged recording sheets and a discharging sheet stacking unit for stacking the discharged recording sheets, the lower surface of the recording sheets discharged from the discharging unit is placed below and adjacent to the discharging unit. A recording sheet supporting means is provided, which is configured to support the recording sheet and to move the recording sheet in the conveying direction when the recording sheet is ejected by a predetermined amount to be separated from the lower surface of the sheet.

Further, an image recording means for recording an image on a recording sheet, a conveying means for conveying the recording sheet, a discharging means for discharging the recording sheet on which the image is recorded, and a discharge sheet stacking for stacking the discharged recording sheet. In the image recording apparatus having the means, after the discharged recording sheets are stacked on the discharged sheet stacking means, discharge sheet pressing means for moving the stacked recording sheets above the image recording apparatus side is provided. And

In the above structure, the leading edge of the recording sheet discharged after recording is temporarily supported by the recording sheet supporting member, and the support is released when the recording sheet is discharged by a predetermined amount. The predetermined amount here is determined by the size of the recording sheet, the ink ejection amount, and the like. After that, the discharging is continued, and after the recording sheets are stacked on the discharging stacker, the recording sheet supporting member returns to the vicinity of the discharging means and is positioned above the trailing end of the recording sheets, so that the rising thereof is prevented.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an image recording apparatus according to an embodiment of the present invention will be described with reference to the drawings.

[First Embodiment] An image recording apparatus according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a structural explanatory view of the image recording apparatus according to the present embodiment, and FIG.
FIG. 3 is a diagram for explaining the operation of the discharging unit, FIG. 3 is a diagram for explaining the progress of stacking of recording sheets on the discharging unit, FIG. 4 is a block diagram of the control system, and FIG. It is a flowchart.

As shown in FIG. 1, this apparatus has a flat bed scanner A in the upper portion and an image recording apparatus B in the lower portion.
And is used as a scanner and a printer by connecting to a personal computer. Note that the information read by the scanner A can be directly recorded by the image recording device B without connecting to a personal computer, and can also be used as a facsimile device by mounting a modem. . Despite being such a multifunctional multifunction device, the image recording device B
By arranging the scanner A on the above, the installation area is almost the same as that of the image recording apparatus B, and the apparatus is compact.

(Scanner) Flatbed scanner A
Is a light source which irradiates a document placed on a platen glass (not shown), causes the reflected light to reach a photoelectric conversion element through a mirror and a lens, and electrically converts image information optically read by the photoelectric conversion element. The signal is converted into a signal and transmitted to the personal computer or the image recording apparatus B below.

(Image Recording Apparatus) This image recording apparatus B is
A sheet P, which is a recording sheet, is supplied from the front of the lower part of the apparatus by a conveying unit, is conveyed by U turns, and is recorded by inkjet recording unit.

(Recording Unit) The recording unit 20 which is the recording unit according to the present embodiment uses a serial type ink jet recording system, and as shown in FIG.
Is slidably held by the guide shafts 21 and 25 so as to be able to reciprocate in the direction orthogonal to the transport direction (sub-scanning direction) of, ie, the main scanning direction. The driving force is transmitted to the carriage 23 via a timing belt (not shown), and the carriage 23 reciprocates in the main scanning direction.

Further, an ink cartridge 24 containing a liquid ink which is an ink medium is detachably mounted on the carriage 23, and the loaded cartridge 24 is
The head holder 23a is connected to the recording head 22 fixed to the carriage 23. A flexible cable (not shown) is connected to the recording head 22, and by transmitting a recording signal to the recording head 22 in response to the movement of the carriage 23, ink is ejected from the head 22 to record an image on the sheet P. To do.

The recording head 22 ejects ink from the ink cartridge 24 in response to a recording signal, and an energy acting portion provided in a part of the ejection port and a droplet forming energy by acting on the ink in the acting portion. It is provided with an energy generating means for generating.

As the energy generating means for generating such energy, a recording method using an electromechanical transducer such as a piezo element, or electromagnetic waves such as a laser is irradiated to generate heat.
Recording method using an energy generating means for ejecting droplets by the action of heat generation, or recording using an energy generating means for heating a liquid by an electrothermal converter such as a heating element having a heating resistor to eject the liquid There are ways.

Among them, a recording head used in an ink jet recording method for ejecting a liquid by thermal energy has liquid ejection ports for ejecting recording liquid droplets and forming ejection liquid droplets arranged at high density. Therefore, it is possible to perform high-resolution recording. Among them, a recording head using an electrothermal transducer as an energy generating means is advantageous because it can be easily made compact, easily mounted at a high density, and inexpensively manufactured. Therefore, in this embodiment, the ink is ejected from the ejection port at the ejection tip by the film boiling pressure generated in the ink due to the heat generation of the electrothermal converter provided in the ejection port.

(Conveying and Ejecting Means) The sheet supply cassette 1 which is a sheet accommodating means for accommodating the sheets P in a stack is a spring
It has an intermediate plate 1b biased upward by 1a and presses the contained sheet P against the sheet conveying roller 2. The middle plate 1b is configured so that it can be pressed downward by a cam (not shown) when the sheet P is added to the cassette 1 and waiting to be fed, such as when the sheet 1 is fed by the cam.
Then, the sheet P is pressed by the conveyance roller 2.

Further, a retard roller 3 is urged to the conveying roller 2, and the conveying roller 2 rotates in the sheet feeding direction while the sheet P is pressed, and at the same time, the retard roller 3 rotates in the sheet returning direction. Both rollers 2,
By the synergistic action of 3, the sheets P are separated and conveyed one by one. After that, the sheet P makes a U-turn along the sheet guide 4 and is sent to the pair of transport rollers 5. As described above, the sheet P is supplied from the lower front side of the apparatus, and is turned to be discharged to the upper front side of the apparatus, whereby the protrusion of the discharge stacker 15 is eliminated and the apparatus is made more compact, and the sheet P is formed. The operability is improved by making it possible to handle only the front of the device.

The sheet P is conveyed to the recording position by the conveying roller pair 5, and a predetermined image is recorded by the recording section described above. The sheet P after recording is discharged by a discharge roller 8 and a spur 9 that presses the sheet P against the discharge roller 16.
And is discharged to the outside of the image recording apparatus B. still,
The spur 9 is made of a material having high water repellency, and is in contact with the recording surface of the sheet P only at the wavy circumferential portion. The spur 9 is provided at a position facing the discharge roller 8 by a bearing member (not shown). The sheet P is arranged at a plurality of positions at predetermined intervals in the width direction (direction orthogonal to the sheet conveying direction), and even if the unfixed image on the sheet immediately after recording is contacted, the sheet P is guided and conveyed without affecting the image. Is configured to.

(Seat supporting means and sheet pressing means)
A sheet supporting member 10, which is a recording sheet supporting unit, is provided outside the discharging unit 16, and has a hinge 12 and an arm 13.
Is formed into a substantially L shape. The hinges 12 are provided on both sides of the sheet width at intervals equal to or larger than the width (length in the direction perpendicular to the sheet conveying direction) of the largest size sheet that can be conveyed by the image recording apparatus B, and the upper end of the image recording is performed by the shaft 11. It is axially supported by the main body of the apparatus B and is rotatable by a drive source (not shown).

An arm 13, which is a plate-shaped member, is attached to the lower ends of both hinges 12 so as to connect both hinges 12. Further, the arm 13 extends a side opposite to a side connected to the hinge 12 to a position below and adjacent to the discharging portion 16. In the present embodiment, the arm 13 constitutes a part of the sheet supporting member and also constitutes a discharged sheet pressing means.

A spur 14 which constitutes a sliding means is provided at the tip of the arm 13. The spur 14 is rotatably attached in the sheet P transport direction and is a member similar to the spur 9 described above. When the arm 13 and the seat P approach each other, the spur 14 comes into contact with the seat P and rotates, thereby reducing friction.

(Control System) Next, a control system for operating each of the above parts will be described. FIG. 4 is a block diagram showing the configuration of the control system, including ROM 26a, RAM 26b, and CPU.
The control unit 26 including 26c and other main components are shown.

The ROM 26a includes various programs for operating the CPU 26c, device drivers such as a motor driver 27 and a head driver 28 for operating various motors and the recording head 22 as shown in the flowchart of FIG. It stores various data required for recording codes and dot patterns.

The RAM 26b also stores a working area in which the CPU 26c temporarily stores the data in the instruction and the calculation result, a buffer area in which various data input from the external device A and the like, a document and the like are stored. It consists of a text area, etc.

The CPU 26c acquires various data from an external device such as an input device, such as the scanner A, and stores the data in the ROM 26a.
Various controls are performed by performing necessary calculations and judgments by the programs and device drivers stored in.

The CPU 26c acquires a recording signal or the like from the external device A or the like and sends a control signal or the like to the head driver 28 to control the recording head 22 to perform printing or the like.
At the same time, by sending a control signal to the motor driver 27, the carry motor 2a, the discharge motor 8a, the carriage motor
23a, and driving of the recording sheet supporting member motor 10a for driving the recording sheet supporting member 10 is controlled. The control of the series of drive devices changes according to the recording information such as the size of the conveyed sheet P and the amount of ink ejected on the sheet P.

(Discharging and Loading Operations) Next, referring to FIGS.
In the image recording apparatus according to the present exemplary embodiment, an operation in the vicinity of the discharging unit when the sheet P is discharged and stacked on the sheet stacking unit will be described with reference to FIGS.

An image is recorded on the sheet P by the recording unit 20 (S
1) and then discharged from the discharge section 16 (S2), the tip of the arm 13 is set to a height lower than that of the discharge section 16 as shown in FIG. The leading edge of the sheet P is supported by the upper surface of the arm 13.

Thereafter, the control system 26 monitors the discharge amount of the sheet P, and detects whether the sheet P has been discharged up to a predetermined amount set according to the recording information such as the sheet size and the ink discharge amount (S3). . When the predetermined amount is reached, the recording sheet support member motor 10 is sent from the CPU 26c through the motor driver 27.
A control signal is sent to a, and as shown in FIG. 2B, the sheet supporting member 10 is rotated in the conveyance direction of the sheet P by a drive source (not shown) to retract (S4). Then, the support of the sheet P is released, and the leading edge of the sheet P falls on the discharge stacker 15.

As shown in FIG. 2C, the sheet P is placed on the discharge stacker 15 (S5) as the discharge progresses, and then the sheet support member 10 is returned to the vicinity of the discharge section 16 again (S6). Let At this time, a large number of stacked sheets P are stacked on the discharge stacker 15 or curls in the opposite direction to those immediately after recording occur due to the passage of time and the leading and trailing edges of the sheet P are lifted. The top surface may rise. Then, it is assumed that the leading end of the sheet supporting member 10 comes into contact with the sheet P, but as shown in FIG. 3, the uppermost surface of the sheet P on which the sheet presser 14 provided at the leading end of the sheet supporting member 10 is stacked. By abutting against each other and rotating, mutual friction can be eliminated. Therefore, the sheet supporting member 10 can return without conveying the sheet P in the reverse direction.

Further, when the sheet supporting member 10 returns to the initial position, as shown in FIG. 3, the sheet presser 14 at the leading end of the sheet supporting member 10 is positioned below the discharging portion 16 and above the trailing end of the stacked sheets P. The rear end of the stacked sheet P is prevented from reaching the discharge portion 16, and the rear end of the already stacked sheet P does not come into contact with the front end of the newly discharged sheet P. Therefore, unlike the conventional example shown in FIG. 11, a sheet discharged later does not slip under the sheet discharged first and the sheet discharged earlier is not pushed out.

[Second Embodiment] A second embodiment according to the present invention will be described with reference to FIG. The same parts as those in the first embodiment will be designated by the same reference numerals and the description thereof will be omitted.

The seat supporting member 30 is substantially L-shaped by the hinge 35 and the arm 36, as in the above embodiment. A carriage 34 is attached to an upper end of the hinge 35, and the carriage 34 is attached to a rail (not shown) so that the carriage 34 can reciprocate in parallel with the conveyance direction of the sheet P. Further, the endless belt 31 is connected to the carriage 34, and the driving force is transmitted. The endless belt 31 is stretched between the drive roller 32 and the driven roller 33, and the drive of the drive roller 32 causes the endless belt 31 to rotate,
That is, the sheet support member 30 is configured to reciprocate. An arm 36 is provided at the lower end of the hinge 35, and the tip of the arm 36 is extended to a position below and adjacent to the discharge unit 16.

When the sheet P is discharged from the discharge section 16 after the image is recorded by the recording section 20, the leading end of the sheet P is supported by the arm 36 as shown in FIG. 6 (a). After that, when the sheet P is discharged to the extent that the sheet P does not roll up in the discharge stacker 15, the driving roller 32 rotates to rotate the sheet P through the endless belt 31 as shown in FIG. 6B.
The sheet 30 is driven in the conveying direction of the sheet P, the support of the sheet P is released, and the leading end of the sheet P drops onto the discharge stacker 15. As the discharge progresses as it is, the sheet P is placed on the discharge stacker 15 as shown in FIG. Then, the sheet supporting member 30 is set before the next sheet P is discharged.
Returns to the vicinity of the discharge unit 16 again.

In the above-described first embodiment, the tip of the sheet supporting member 10 draws a circular motion, whereas in the present embodiment, the sheet supporting member 10 moves substantially parallel to the stacked sheets P. Therefore, the leading end of the sheet supporting member 10 and the sheet P do not come into large contact with each other. Therefore, no sliding member is provided, and the tip of the arm 36 of the sheet supporting member 10 also serves as a sheet pressing member. Further, a more preferable configuration can be provided by providing a detection member that detects the stacking limit of the discharge stacker 15 before or when the sheet P contacts the sheet P.

The control system of the second embodiment is almost the same as that of the first embodiment, but the recording sheet supporting member motor 10a is driven by the drive roller 32 instead of rotating the shaft.
The endless belt 31 is rotated by rotating the recording sheet supporting member 30.

In this way, similarly to the first embodiment, the deep paper discharge stacker 15 capable of stacking a large number of sheets P can be mounted, and the sheets P are preferably discharged and stacked from the start to the end. Can be done.

[Other Embodiments] In the first and second embodiments described above, a part of the sheet supporting means constitutes the sheet pressing means. However, even if either one of the sheet supporting means or the sheet pressing means, or both are provided independently, the respective effects can be obtained,
It is possible to preferably discharge or stack the sheets.

In the above first embodiment, the arm
Although the spur 14 which is the sliding means is provided at the tip of the recording sheet 13, it is possible to suitably discharge and stack the recording sheets without providing the sliding means as shown in FIG. Further, in the first embodiment, the sliding means is shown as a spur, but it may be any one capable of reducing friction such as providing a sled member such as a leaf spring.

Further, although the recording sheet supporting means is formed in the L-shape in the above embodiment, it may have any shape or structure capable of supporting the leading end of the discharged recording sheet. Further, the control system of the image recording apparatus is not limited to the one described above, and should be set according to the configuration of the apparatus.

Although the recording sheet supporting means is pivotally supported and rotated or moved by an endless belt, the present invention is not limited to this, and a solenoid may be used or ejected. Various methods are conceivable, such as utilizing the conveyance force of the recording sheet.

Further, although the example in which the ink jet recording system is used as the recording means of the image recording apparatus has been shown, the ejected recording sheet is placed on the ejected sheet stacking means even when the electronic recording system or the thermal transfer recording system is used as the recording means. It is possible to obtain the effect of suitable loading.

[0053]

With the above-described structure, the image recording apparatus according to the present invention does not cause conveyance defects such as curling even if the height difference between the sheet discharging means and the discharged sheet stacking means is increased. The recording sheets can be stacked appropriately on the discharge sheet stacking unit.

Even if a large number of recording sheets are stacked on the discharge sheet stacking means or the stacked recording sheets are dried and curled in the opposite direction, the trailing end of the recording sheet is discharged sheet pressing means. Since the sheet P does not reach the sheet ejection means by contacting the lower surface of the sheet P, the rear end of the previously ejected recording sheet does not collide with the leading edge of the next ejected recording sheet.

Therefore, from the above, it is possible to continuously perform high-speed printing of a large number of full-color printings even in an ink jet recording system in which curling easily occurs.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory diagram of an image recording unit according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating operations of a sheet supporting unit and a sheet pressing unit.

FIG. 3 is a diagram illustrating a state where a stack of recording sheets has progressed on a discharging unit.

FIG. 4 is a configuration block diagram of a control system.

FIG. 5 is a flowchart showing an operation of a recording sheet support member.

FIG. 6 is a diagram illustrating a second embodiment according to the present invention.

FIG. 7 is a diagram illustrating another embodiment according to the present invention.

FIG. 8 is a diagram illustrating a shape of a curl on a sheet in a sheet.

FIG. 9 is a diagram illustrating a change in curl shape with the passage of time.

FIG. 10 is a diagram illustrating a conventional example when a difference in height between a discharge unit and a discharge stacker is large.

FIG. 11 is a diagram illustrating a conventional example when a difference in height between a discharge unit and a discharge stacker is small.

[Explanation of Codes] A ... Scanner B ... Image Recording Device P ... Sheet 1 ... Sheet Supply Cassette 2 ... Conveying Roller 3 ... Retard Roller 4 ... Sheet Guide 5 ... Conveying Roller Pair 10 ... Sheet Supporting Member 11 ... Shaft 12 ... Hinge 13 … Arm 14… Sheet retainer 15… Ejection stacker 16… Ejection section 20… Recording section 21… Guide shaft 22… Recording head 23… Carriage 24… Cartridge 25… Guide shaft 26… Control section 30… Sheet support member 31… Endless belt 32 … Drive roller 33… Driven roller 34… Carriage 35… Hinge 36… Arm

Claims (7)

[Claims] 1. An image recording unit that records an image on a recording sheet, a conveying unit that conveys the recording sheet, a discharging unit that discharges the recording sheet on which an image is recorded, and a stack of the discharged recording sheets. Discharge sheet stacking means, and a recording sheet supporting means configured to support the leading end portion of the discharged recording sheet in the conveyance direction and to be movable in the conveyance direction of the recording sheet, at a position below and adjacent to the discharge means. An image recording apparatus comprising: 2. The recording sheet supporting means supports the lower surface of the recording sheet discharged from the discharging means, and moves in the conveying direction of the recording sheet when the recording sheet is discharged by a predetermined amount. The image recording apparatus according to claim 1, wherein the image recording apparatus is configured to be separated from the lower surface of the sheet. 3. An image recording unit that records an image on a recording sheet, a conveying unit that conveys the recording sheet, a discharging unit that discharges the recording sheet on which an image is recorded, and a stack of the discharged recording sheets. Discharge sheet stacking means, and discharge sheet pressing means for moving the discharged recording sheets above the image recording apparatus side of the stacked recording sheets after being stacked on the discharge sheet stacking means. An image recording device characterized by the above. 4. A discharged sheet that is moved above the image recording apparatus side of the stacked recording sheets after the discharged recording sheets are stacked on the discharged sheet stacking unit on the recording sheet supporting unit. The image recording apparatus according to claim 1 or 2, further comprising a pressing unit. 5. The image according to claim 3, wherein the recording sheet pressing means is a sliding means that is in sliding contact with the recording sheets stacked on the discharge sheet stacking means and does not move the recording sheets. Recording device. 6. The image recording apparatus according to claim 1, wherein the image recording unit is configured by an ink jet recording system that ejects ink in accordance with a signal to perform recording. . 7. The image recording unit discharges ink from a discharge port by utilizing film boiling generated in the ink by thermal energy applied by an electrothermal converter. Image recording device.