JP2002001940A - Ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enlarge a width of a recording head in the sub-scanning direction in an ink jet recorder. SOLUTION: The ink jet recorder comprises a carriage 2 arranged in parallel to a main scanning direction movably in reciprocation, a recording head 1 mounted on the carriage 2 for ejecting ink downward from a plurality of nozzles, a transportation roller 13 for transporting a recording medium, on which the ink ejected from the recording head 1 adheres and an image is formed to the sub-scanning direction rectangular to the main scanning direction, a discharge roller 19 for discharging the recording medium to the outside of the device by rotating simultaneously with the roller 13, mounted in the transporting direction of the recording medium and upstream of the transportation roller 13. The whole width of the sub-scanning direction of the carriage 2 is put in a position between the transportation roller 13 and the discharging roller 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus which performs recording by discharging ink from nozzles and attaching the ink to a recording medium.

[0002]

2. Description of the Related Art An ink jet recording apparatus is an inexpensive technique for achieving high image quality and high-speed printing.
It is widely used in copiers, facsimile machines, printers, word processors, and the like.

Various techniques have been proposed for such an ink jet recording apparatus, and techniques suitable for high-speed recording, high resolution, and full color are still being studied intensively.

According to the recording principle of the ink jet, as a means for generating energy for flying a coloring material, a device using a heating resistor such as an electrothermal conversion device, a device using a piezo element such as an electromechanical conversion device, and the like. There is an electrostatic type using electric energy as it is. As a recording head used in an ink jet recording apparatus, a serial scanning head mounted on a carriage and moving in a direction (main scanning direction) orthogonal to a recording paper conveyance direction (sub scanning direction) to perform recording. Has been put to practical use.

Here, as one of means for performing high-speed printing in the ink jet printing apparatus, it is conceivable to increase the width of the printing head in the sub-scanning direction to increase the printing width in one main scanning direction. .

FIG. 5 is a sectional view of a main part of a conventional ink jet recording apparatus.

As shown, the carriage 102 is mounted on a carriage shaft 110 and a guide rail 111 so as to be reciprocally movable in the main scanning direction.
At the bottom of the carriage 102, there is provided a recording head 101 formed with a plurality of nozzles and ejecting ink downward. A sub-tank 103 is provided on the upper portion of the carriage 102, and the ink stored in the sub-tank 103 is supplied to the recording head 101. The apparatus main body is provided with a main tank 120 in which ink to be supplied to the sub tank 103 is stored.

Below the carriage 102, a transport roller 113 for transporting a recording medium on which an image is formed by ink discharged from the recording head 101 in the sub-scanning direction is arranged. Further, a paper discharge roller 119 that discharges the recording medium out of the apparatus is disposed forward of the conveyance roller 113 in the conveyance direction of the recording medium. The recording head 101 is located between the transport roller 113 and the paper discharge roller 119.

[0009]

In such a conventional ink jet recording apparatus, the length of the recording head is restricted by the conveying roller and the discharge roller, and the width of the recording head in the sub-scanning direction is increased. Can not.

[0010] In this case, the printing area in one main scan cannot be widened, and high-speed printing cannot be performed.

Accordingly, an object of the present invention is to provide an ink jet recording apparatus capable of increasing the width of a recording head in the sub-scanning direction.

[0012]

In order to solve this problem, an ink jet recording apparatus according to the present invention includes a carriage provided reciprocally in parallel with a main scanning direction, a carriage mounted on the carriage, and a plurality of nozzles. A recording head that ejects ink, a conveying unit that conveys the recording medium on which the ink ejected from the recording head adheres to form an image in a sub-scanning direction that is orthogonal to the main scanning direction, And a paper discharge means for discharging the recording medium out of the machine in the transport direction, wherein the entire width of the carriage in the sub-scanning direction is located between the transport means and the paper discharge means.

As described above, the conveying means and the paper discharging means are separated from each other such that the entire width of the carriage in the sub-scanning direction is located between the conveying means and the paper discharging means. Can be widened.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to a first aspect of the present invention is directed to a carriage provided reciprocally in parallel with the main scanning direction, and a recording head mounted on the carriage and discharging ink from a plurality of nozzles. Transport means for transporting a recording medium on which ink ejected from the recording head adheres to form an image in a sub-scanning direction orthogonal to the main scanning direction; and An ink jet recording apparatus having a paper discharging means for discharging the recording medium out of the machine, wherein the full width of the carriage in the sub-scanning direction is located between the conveying means and the paper discharging means. Since the conveying means and the paper discharging means are separated so that the entire width of the paper is located between the conveying means and the paper discharging means, the width of the recording head in the sub-scanning direction can be increased. .

According to a second aspect of the present invention, in the first aspect of the present invention, a sub-tank which is mounted on a carriage and stores ink to be supplied to a recording head and is fixedly provided on an apparatus body, An ink jet recording apparatus comprising: a main tank storing ink to be supplied to a subtank via a flexible supply tube; and a full width of the carriage in a subscanning direction is located between a conveying unit and a paper discharging unit. Since the conveying means and the paper discharging means are separated from each other, the width of the recording head in the sub-scanning direction can be increased.

According to a third aspect of the present invention, in accordance with the first or second aspect of the present invention, the driving force of the driving means for operating the conveying means between the conveying means and the paper discharging means is controlled by the conveying means. A cleaning means for cleaning the nozzles is disposed on the same side as the driving force transmitting means for transmitting the ink to the ink jet recording apparatus, and has an effect that the width of the carriage in the moving direction can be reduced.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. In these drawings, the same members are denoted by the same reference numerals, and duplicate description is omitted.

FIG. 1 is a perspective view schematically showing an ink jet recording apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view showing a main part of the ink jet recording apparatus shown in FIG. 1, and FIG. FIG. 4 is an explanatory view showing an ink supply state of a recording apparatus, and FIG. 4 is an explanatory view showing an ink supply state of another inkjet recording apparatus as a comparative example.

As shown in FIG. 1, the ink jet recording apparatus according to the present embodiment has a recording head 1 for discharging inks of a plurality of colors. The recording head 1 includes a black recording head 1a that discharges black ink, a yellow recording head 1b that discharges yellow ink, a magenta recording head 1c that discharges magenta ink, and a cyan recording head 1d that discharges cyan ink. The recording heads 1a, 1b, 1c, 1d are formed with a plurality of nozzles (not shown) from which ink is ejected. Above these recording heads 1a, 1b, 1c, 1d, black ink, yellow ink, magenta ink, and cyan ink are stored, respectively, and the recording heads 1a, 1c are stored.
sub tanks 3a, 3 for supplying ink to b, 1c, 1d
b, 3c and 3d are arranged. The recording head 1 and the sub-tank 3 are provided on the carriage 2 in the moving direction of the carriage 2.

The recording heads 1a, 1b, 1c, 1d
May exist independently or may be integrated. The number of colors is four in the present embodiment, but is not limited to this, and may be five or six as long as the number is four or more. In that case, the number of recording heads, ink tanks, sub-tanks, supply tubes, and the like increase or decrease according to the number of colors.

At the position corresponding to the nozzle of the recording head 1, there is provided a pressure chamber filled with ink, and a piezoelectric element, and the volume of the pressure chamber is reduced by applying a voltage to the piezoelectric element in a pulsed manner. And a piezoelectric actuator (not shown), which is operated by a drive circuit 4 installed on the carriage 2, so that the ink in the pressure chamber is positioned below the nozzles on the recording paper (recording paper). (Medium) 5. The recording paper 5 is transported in the Y direction in FIG. As the actuator, a conventionally known actuator such as a thermal method or an electrostatic method may be used.

The recording head 1 is fixed to a carriage 2 that can move relative to the recording paper 5. Carriage 2
Is provided on one side in a direction (X direction in FIG. 1) orthogonal to the conveying direction of the recording paper 5 (Y direction in FIG. 1) and parallel to the recording surface of the recording paper 5 and is rotated by the carriage drive motor 6. An endless carriage drive belt 9 that is suspended between the drive pulley 7 and a driven pulley 8 provided on the opposite side of the drive pulley 7 and rotates in two directions, forward rotation and reverse rotation, is fixed to the lower span of the belt 9. X in FIG.
The carriage 2 extends slidably through a carriage shaft 10 attached to the apparatus main body, and slides on a guide rail 11 arranged in parallel with the carriage shaft 10 on the opposite side to the carriage shaft 10 with the carriage 2 interposed therebetween. It is movably supported.

Accordingly, when the carriage driving belt 9 is rotated by the driving pulley 7 and the driven pulley 8 by the rotation of the carriage driving motor 6, the carriage 2 fixed to the carriage driving belt 9 moves the carriage shaft 10 and the guide rail. 11, while reciprocating in the scanning direction, which is the X direction in FIG.

The carriage drive motor 6 is provided with a rotation detection board 12, and the rotation amount of the carriage drive motor 6 (that is, X of the recording head 1) is determined by the rotation detection board 12 and a detection sensor (not shown). Direction position) is detected.

The recording paper 5 comprises a transport roller (transporting means) 13 extending in the X direction below the recording paper 5,
The recording paper 5 is sandwiched between a pinch roller 14 that presses the recording paper 5 against a transport roller 13 above the recording paper 5. A conveying motor (driving means) 15 composed of a DC motor (DC motor) is disposed behind the pinch roller 14 in the conveying direction of the recording paper 5, and a conveying motor 15 is provided between the conveying motor 15 and the conveying roller 13. A transmission gear train (driving force transmitting means) 16 for transmitting the driving force of the
6 attached. Thereby, the transport roller 13 is driven by the transport motor 15 and the recording paper 5
Is transported in the Y direction. Then, at this time, the pinch roller 1
4 is driven and rotated by the recording paper 5 being conveyed.

In the present embodiment, a DC motor is used as the transport motor 15 in consideration of speeding up operation and quiet operation noise, but a stepping motor may be used.

In the present embodiment, the driving force transmitting means comprises a transmission gear train 16 constituted by a plurality of gears, and the driving force of the transport motor 15 is transmitted by such a transmission gear train 16. However, the driving force transmission means includes a pulley and a belt, or a gear and a shaft,
Furthermore, various means capable of transmitting the driving force of the transport motor 15 to the transport roller 13, such as a combination thereof, can be realized, and the present invention is not limited to this embodiment.

On one side of the transport roller 13, a final gear 16a constituting the transmission gear train 16 is mounted coaxially with the rotation axis of the transport roller 13. Furthermore, the final gear 1
A rotation detection board 17 similar to the rotation detection board 12 of the carriage drive motor 6 is mounted on the outer side of 6a in the same manner as the rotation axis of the transport roller 13. Further, it is preferable that a chassis 26 be interposed between the rotation detecting board 17 and the recording head 1.

Although the rotation detecting board 17 is provided coaxially with the final gear 16a here, it may be provided anywhere on the path from the transport motor 15 to the transport roller 13.

A chassis 26 is interposed between the rotation detecting board 17 and the recording head 1.

A plurality of slits extending in the radial direction are formed at equal intervals on the outer periphery of the rotation detecting board 17 over the entire circumference. At a predetermined position of such a rotation detection board 17, a detection sensor 18 for detecting the position of the slit is provided. The detection sensor 18 includes a light emitting unit that emits detection light toward the rotation detection board 17 and a light receiving unit that is disposed on the opposite side of the light emission unit with the rotation detection board 17 interposed therebetween and receives the detection light emitted from the light emission unit. And a part. Then, when the rotation detecting plate 17 is rotated by the final gear 16a via the transport roller 13, the detection light is shielded and transmitted by the movement of the slit, and the light receiving portion recognizes the light.
Is detected, whereby the rotation amount of the transport motor 15, that is, the feed amount of the recording paper 5 is detected.

The detection sensor 18 includes the rotation detection board 1
7 is a reflection type in which a light emitting unit and a light receiving unit are arranged on one side of the rotation detection board 17 to detect reflected light, instead of a transmission type in which a light emitting unit and a light receiving unit are arranged to detect transmitted light. Can also be used.

A pair of paper discharge rollers (paper discharge means) 19a, 19b for nipping and transporting the conveyed recording paper 5 and discharging the recording paper 5 to the outside of the apparatus are provided forward of the conveyance roller 13 in the conveyance direction of the recording paper 5. ing.

As shown in the figure, between the pinch roller 14 and the transport motor 15, main tanks 20a, 20b, 20c, 20 storing the above-described black ink, yellow ink, magenta ink, and cyan ink, respectively, are provided.
d are fixed to the apparatus main body and provided side by side in the X direction.

Main tanks 20a, 20b, 20c, 2
0d and the sub tanks 3a, 3b, 3c, 3d are provided with four flexible supply tubes 21a, 21b for supplying the ink in the main tanks 20a, 20b, 20c, 20d into the sub tanks 3a, 3b, 3c, 3d. , 21c, 21d
Communication. These four supply tubes 21
Are connected in the main tank 20 in the conveying direction of the recording paper 5 in the conveying direction, are arranged in the vertical direction, are arranged in the vertical direction, extend in the Y direction, and then follow the pulley 8 in the X direction.
Side, further curved and extend to the drive pulley 7 side in the X direction to reach the carriage 2.

The position of the curved portion of each supply tube 21 changes as the carriage 2 moves in the X direction, so that the carriage 2 moves smoothly.

Here, for example, A
Inks corresponding to several sheets of recording paper 5 of four sizes are stored. During printing, the ink in the sub-tank 3 is ejected, and the ink is replenished from the main tank 20 to the sub-tank 3 using the time when the next recording paper 5 is introduced.

As described above, the sub-tank 3 is provided on the carriage 2 to increase the ink supply speed and prevent the ink from running out. In addition, by reducing the total mass of the carriage 2 by using a small tank called the sub-tank 3, The size of the apparatus is reduced by increasing the moving speed and narrowing the moving space of the carriage 2.

On the side surface of the carriage 2, besides the supply tube 21, a print signal for discharging ink from the recording head 1 is transmitted from a print signal generator (not shown) to the drive circuit 4. A flat cable 23 is attached. Then, the above-described piezoelectric element is driven by a print signal transmitted via the flat cable 23, and ink is ejected from the nozzles of the recording head 1.

At a position of the home position of the carriage 2 on the driven pulley 8 side, a purge unit (cleaning means) 24 as suction means for sucking ink adhered to the nozzles of the recording head 1 and cleaning the nozzles is arranged. ing.

The purge unit 24 is moved in the Z direction to cover the outer openings of all the nozzles of the recording head 1, and the cap 24 a is brought into close contact with the recording head 1, and the cap 24 a is brought into close contact with the recording head 1. Discharge tube 24b which communicates the closed space formed by the above with the waste ink container 25 arranged adjacent to the main tank 20.
And a suction pump 24c provided on the ink discharge tube 24b to suction ink attached to the nozzle and discharge the ink to the waste ink container 25.

The recording head 1 is located adjacent to the cap 24a.
A rubber wiper 24d for wiping the nozzle surface is provided. The wiper 24d is provided so as to be movable in the Z direction independently of the cap 24a. The wiper 24d is repositioned between a compression position where the wiper is pressed against the nozzle surface of the recording head 1 and a retracted position where the wiper 24 is retracted from the recording head 1. It is possible. By moving the carriage 2 in the scanning direction with the wiper 24d pressed against the nozzle surface of the recording head 1, the wiper 24d relatively moves with respect to the nozzle surface, and the ink and the like attached to the nozzle surface are wiped. You.

Here, as shown in FIG.
The total width in the sub-scanning direction is the distance between the transport roller 13 and the paper discharge roller 19.
a and 19b, the conveying roller 13 and the paper discharging rollers 19a and 19b are separated from each other, for example, 50 m.
They are arranged at intervals of about m. However, roller 1
The interval between 3 and 19 is not limited to 50 mm.

Therefore, it is possible to increase the width of the recording head 1 in the sub-scanning direction, and to form a large number of nozzles for ejecting ink in the sub-scanning direction. The width is increased, and high-speed printing can be performed.

In this specification, the total width W of the carriage 2 in the sub-scanning direction is defined as the carriage shaft 1
This is a concept indicating the entire width of the print function portion such as the recording head 1 and the sub tank without including the portion through which 0 passes, that is, the movement function portion of the carriage 2. Therefore, it is not necessary that the width in the sub-scanning direction including the portion where the carriage shaft 10 of the carriage 2 penetrates is located between the transport roller 13 and the paper discharge roller 19. However, the width in the sub-scanning direction including the portion where the carriage shaft 10 of the carriage 2 penetrates may be located between these rollers 13 and 19.

In this manner, the carriage 2 and the paper discharge roller 19 are spaced apart from each other so that the entire width of the carriage 2 in the sub-scanning direction is located between the conveying roller 13 and the paper discharging roller 19, so that the printing width in one main scanning direction is obtained. Is widened, the time required for the printed portion of the recording paper 5 to reach the paper discharge roller 19 is increased, and ink drying can be promoted.

Further, the transport roller 13 and the discharge roller 19
And the distance between the conveying roller 13 and the discharge roller 1 is increased.
Since the print content of the recording paper 5 can be confirmed from the gap with the recording paper 9, it is possible to confirm the print immediately after the printing, not after the paper is discharged by the paper discharge roller 19. As a result, a printing setting error can be quickly found.

Since the width of the recording head 1 in the sub-scanning direction can be increased, the accuracy of adjusting the parallelism between the nozzle surface of the recording head 1 and the platen opposed to the nozzle surface is improved, so that the carriage 2 Head gap assembling accuracy is improved.

Since the distance between the transport roller 13 and the paper discharge roller 19 is increased and the width of the upper surface of the carriage 2 in the sub-scanning direction can be increased, the sub-tank attached to the carriage 2 is increased in width to increase the height. This makes it possible to reduce the size of the device.

Further, since the height of the sub-tank 3 attached to the carriage 2 can be suppressed by making it wider, the amount of change in the water level of the sub-tank 3 due to consumption of ink can be reduced. That is, as shown in FIG. 4, when the height of the sub-tank 103 is high, the water level change H2 due to the consumption of ink per predetermined unit increases,
As shown in FIG. 3, when the height of the sub tank is low, the water level change H1 is smaller than the water level change H2 in FIG. Accordingly, the shape of the meniscus M formed in the nozzle is stabilized without depending on the amount of stored ink in the sub-tank 3, so that the amount of ejected ink can be kept constant.

Further, since the height of the sub-tank 3 attached to the carriage 2 can be suppressed by increasing the width thereof, the center of gravity of the carriage 2 is reduced, the displacement of the center of gravity is reduced, and the carriage 2 can run stably.

Further, since a large number of nozzles can be formed in the sub-scanning direction, the number of nozzles in the main scanning direction can be reduced, so that the size of the carriage 2 in the main scanning direction can be reduced.

Further, the distance between the transport roller 13 and the paper discharge roller 19 is increased, so that the purge unit 24 can be disposed between the rollers 13 and 19, and the transmission gear train 16 is provided.
And the purge unit 24 are installed on the same side,
It is possible to make the width of the carriage 2 in the moving direction compact.

In addition, an increase in the width of the carriage, an increase in the carriage moving speed, and a reduction in the size of the ejected ink cause a problem of scattering of ink mist. this is,
Resolution of 600 dpi or higher, printing speed of 20 kHz
Above, 80 cm / sec or more, carriage width 40 mm
As described above, the ink discharge amount starts to appear in a device that prints small droplets of 20 pl or less at high speed, and the carriage width is 50 mm
As described above, when the ink ejection amount is 4 pl or less, it appears particularly remarkably.

On the other hand, in this embodiment, the ink mist scattered adheres to the rotation detecting board 17 by disposing the rotation detecting board 17 outside the recording head 1 from the final gear 16a or the chassis 26. Thus, it is possible to prevent a situation in which a rotation angle detection error occurs.

By providing the light emitting portion or the light receiving portion of the detection sensor 18 between the final gear 16a and the rotation detection board 17, an ink mist generated due to an increase in carriage width, high-speed printing, and small droplet ejection can be detected. 18 can be configured to be difficult to adhere to.

In this embodiment, the rotation detecting plate 17 is attached to the same conveying roller 13 as the final gear 16a to eliminate a rotational angle detection error due to backlash. It may be mounted coaxially with the rotation axis.

In this embodiment, the main tank 20 is provided separately from the carriage 2.
The ink tank 20 may be provided on the carriage 2, or may be of a cartridge type in which the head and the ink tank are integrated.

In this embodiment, an optical type rotation detecting board 17 has been mainly described. However, a similar effect can be obtained by using a magnetic type having a magnetic stripe and a magnetic detection sensor. be able to.

[0060]

As described above, according to the present invention, the conveying means and the paper discharging means are separated so that the entire width of the carriage in the sub-scanning direction is located between the conveying means and the paper discharging means. In addition, an effective effect that it is possible to increase the width of the recording head in the sub-scanning direction is obtained.

As a result, an effective effect that the printing width in one main scanning direction is widened and high-speed printing can be performed can be obtained.

Since the carriage is spaced apart so that the entire width of the carriage in the sub-scanning direction is located between the conveying means and the paper discharging means, and the printing width in one main scanning direction is large, the recording is performed. An effective effect is obtained in that the time required for the printed portion of the medium to reach the paper discharging means is increased, and ink drying can be promoted.

Since the distance between the transporting means and the paper discharging means is widened and the print content of the recording medium can be confirmed from the gap between the transporting means and the paper discharging means, the printing can be confirmed immediately after printing. Is obtained.

Since the width of the recording head in the sub-scanning direction can be widened, it is easy to visually check the parallelism between the nozzle surface of the recording head and the platen facing this nozzle surface, and the head gap assembling accuracy of the carriage is improved. Is improved.

Since the distance between the conveying means and the paper discharging means is increased and the width of the upper surface of the carriage in the sub-scanning direction can be increased, the height of the sub-tank attached to the carriage can be suppressed by increasing the width. As a result, an effective effect that the size of the apparatus can be reduced can be obtained.

Since the height of the sub-tank attached to the carriage can be suppressed by increasing the width, the amount of change in the water level of the sub-tank due to ink consumption can be reduced.
Since the shape of the meniscus formed in the nozzle is stable,
An effective effect that it is possible to make the amount of ink ejected constant can be obtained.

Since the height of the sub-tank attached to the carriage can be suppressed by increasing the width thereof, the center of gravity of the carriage is reduced, the displacement of the center of gravity is reduced, and an effective effect of enabling the carriage to run stably is obtained. .

Since a large number of nozzles can be formed in the sub-scanning direction, the number of nozzles in the main scanning direction can be reduced, so that the size of the carriage in the main scanning direction can be reduced. The effect is obtained.

Since the distance between the conveying means and the paper discharging means is widened and the purge unit can be arranged between these rollers, if the driving force transmitting means and the purge unit are installed on the same side, An effective effect that the width in the moving direction can be made compact can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a main part of the ink jet recording apparatus of FIG. 1;

FIG. 3 is an explanatory diagram illustrating an ink supply state of the inkjet recording apparatus of FIG. 1;

FIG. 4 is an explanatory diagram showing an ink supply state of another inkjet recording apparatus as a comparative example.

FIG. 5 is a sectional view showing a main part of a conventional ink jet recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording head 2 Carriage 3 Sub tank 5 Recording paper (recording medium) 13 Conveying roller (conveying means) 15 Conveying motor (driving means) 16 Transmission gear train (driving force transmitting means) 16a Final gear 17 Rotation detecting board 18 Detection sensor 19 Discharge Paper roller (discharge means) 19a Discharge roller (discharge means) 19b Discharge roller (discharge means) 20 Main tank 21 Supply tube 24 Purge unit (cleaning means)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kensei Otsubo 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. F-term (reference) 2C056 EA01 HA28 HA29 HA37 JC06 JC13 JC20 KB37 KC02

Claims (3)

[Claims] A carriage mounted on the carriage so as to reciprocate in parallel with the main scanning direction, a recording head for ejecting ink from a plurality of nozzles, and an ink ejected from the recording head adhered to the carriage. Transporting means for transporting a recording medium on which an image is formed in a sub-scanning direction orthogonal to the main scanning direction, and disposed before the transporting means in the transporting direction of the recording medium, and discharging the recording medium outside the machine. An ink jet recording apparatus, comprising: a paper discharge unit that moves the carriage, and the entire width of the carriage in the sub-scanning direction is located between the transport unit and the paper discharge unit. 2. A sub-tank mounted on the carriage and storing ink to be supplied to the recording head, and an ink supplied to the sub-tank via a flexible supply tube fixed to the apparatus main body and provided. 2. The ink jet recording apparatus according to claim 1, further comprising: a main tank storing the ink. 3. The nozzle is provided between the transporting means and the sheet discharging means and on the same side as the driving force transmitting means for transmitting the driving force of the driving means for operating the transporting means to the transporting means. 3. The ink jet recording apparatus according to claim 1, further comprising a cleaning unit for cleaning.