JP2004066576A - Inkjet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recorder in which print quality can be enhanced by suppressing or preventing oscillation during a print operation. <P>SOLUTION: The inkjet recorder comprising an endless belt member 8 disposed oppositely to a recording sheet A being carried and reciprocatedly in the direction intersecting the carrying direction of the recording sheet A, and a print unit 2 fixed to the belt member 8 in order to print on the recording sheet A is provided with a balancer unit 3 having a mass identical to that of the print unit 2 and being fixed to the belt member 8 at a position symmetric to the print unit 2 with respect to the center of the belt member 8. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ink jet recording apparatus that ejects ink droplets and records characters and images on recording paper, and more particularly to an ink jet recording apparatus that has a plurality of color ink tanks and can perform color printing.
[0002]
[Prior art]
In general, an inkjet recording apparatus does not require processes such as development and fixing, and is configured to record on recording paper in a non-contact manner. Therefore, the operation sound during recording is extremely low, and high-speed printing is possible. In addition, since the ink has a high degree of freedom, it has many advantages such as the use of inexpensive plain paper. In this ink jet recording apparatus, printing is performed by moving the printing unit in the width direction of the recording paper in the main scan, and the recording paper is conveyed in the sub-scan, and printing is performed on the recording surface of the recording paper by repeating these alternately. are doing. Therefore, writing can be performed on the entire surface of the recording paper.
[0003]
At this time, in the sub-scanning, the recording sheet having little mass is moved, whereas in the main scanning, the printing unit having large mass is moved at high speed. That is, the printing unit mainly includes a print head unit that executes printing by ejecting ink droplets, an ink tank that supplies ink to the print head unit, and a case that stores these. In particular, recently, there has been an increasing demand for higher quality as much as photographic image quality. In order to respond to such high image quality, a large number of colors are required, so that the number of ink tanks is increased, and the size and weight of the printing unit tend to increase. On the other hand, in order to cope with high-speed recording, the printing unit is moved at high speed. As a result, since the amount of inertia when the object makes a linear motion is mass, the printing unit has a large inertia (inertia) during the printing operation.
[0004]
That is, FIG. 4 shows a main part of a conventional ink jet recording apparatus 50. The printing unit 51 performs writing in the entire recording width of the recording paper A by performing a reciprocating motion indicated by an arrow in the main scanning direction. That is, in the ink jet recording apparatus 50, a guide rod 52 is provided so as to intersect with the transport direction of the recording paper A, and the printing unit 51 is tightly attached to the guide rod 52, and the printing unit 51 is moved along the intersecting direction. A driving pulley 53a and a driven pulley 53b are provided at both sides of the recording paper A to be conveyed, and a timing belt 54 is wound around these pulleys 53a and 53b. The print unit 51 is reciprocated in the width direction of the recording paper A by rotating the drive pulley 53a forward and reverse by a motor 55. Although the printing unit 51 is driven by the timing belt 54 in this example, a configuration in which the printing unit 51 is driven by a wire or the like is also known. At this time, since the printing unit 51 is reciprocated at high speed in the range indicated by the arrow, the start and stop of the movement of the printing unit 51 are frequently repeated.
[0005]
[Problems to be solved by the invention]
As described above, in the conventional inkjet recording apparatus, at the time of the printing operation, the vibration of the printing unit is caused by the start and stop of the movement of the printing unit, and the vibration of the printing unit has been a problem. In addition, at the time of printing, the start and stop of the movement of the printing unit are frequently repeated, so that the printing unit also vibrates frequently.
[0006]
That is, since the printing unit having a large mass is moved on a straight line at a high speed, the printing unit has a large inertia. In order to move the printing unit at a high speed or to stop the printing unit from moving at a high speed, it is necessary to rapidly apply a large force to the printing unit. For this reason, the large inertia of the printing unit causes vibration, and the printing unit vibrates along with the start and stop of the movement.
[0007]
Thus, the printing unit vibrates in this way, which has a considerable effect on the printing quality, and the frequent vibrations cause inconvenience to the user. In particular, since the operation noise during printing is low in the ink jet recording apparatus, noise due to the vibration becomes conspicuous, and the quietness is reduced. In addition to this, for example, when the inkjet recording apparatus is employed as a part of a multifunction peripheral including another apparatus that performs a mechanical operation such as a reading unit, such a vibration is generated by another apparatus. There was a risk of affecting mechanical operation.
[0008]
Accordingly, it is an object of the present invention to provide an ink jet recording apparatus which solves the above-mentioned problems of the related art and suppresses or prevents vibrations during printing to improve print quality.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1, wherein the endless belt is arranged to face a recording sheet to be conveyed, and is capable of reciprocating in a direction intersecting the conveying direction of the recording sheet. In an ink jet recording apparatus comprising a member and a printing unit mounted on the belt member and printing on the recording paper, the printing unit is mounted on the belt member at a position symmetrical to the printing unit with respect to a center of the belt member, A balancer unit having the same mass as the printing unit is provided.
[0010]
According to a second aspect of the present invention, in the first aspect, the endless belt member is wound around a pulley member provided on both sides of the recording sheet, and one of the pulley members is rotated by a motor. It is characterized by having a configuration.
[0011]
According to a third aspect of the present invention, in the first or second aspect, the balancer unit is a second printing unit that prints in conjunction with the printing unit.
[0012]
According to a fourth aspect of the present invention, in the third aspect, the printing area assigned to the printing unit and the second printing unit is an area divided right and left with a center line in the width direction of the recording paper as a boundary. It is characterized by the following.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a first embodiment of the present invention, and FIG. 1 is a perspective view showing a main part of an ink jet recording apparatus according to the first embodiment.
[0014]
That is, the inkjet recording apparatus 1 includes a guide rod 4 that slidably supports the printing unit 2 and the balancer unit 3, a motor 5 serving as a driving source, a driving pulley 6 that is rotationally driven by the motor 5, It has a timing belt 8 stretched over a driving pulley 6 and a driven pulley 7, and performs a predetermined feeding operation of the recording paper A transported by a transport mechanism (not shown). Thus, the printing unit 2 and the balancer unit 3 are reciprocated in conjunction with each other to print on the recording paper A. The transport mechanism is configured to transport the recording paper A at a predetermined speed by an arbitrary length while maintaining a state in which the recording surface on which the recording paper is printed faces the printing unit 2 side. The operation of moving the printing unit 2 and the balancer unit 3 by the motor 5, the printing operation by the printing unit 2, and the operation of transporting the recording paper A by the transport mechanism are linked to each other by a control mechanism (not shown). Is controlled as follows.
[0015]
The guide rod 4 is formed in a long rod shape having a predetermined straightness and a predetermined diameter, and has sufficient strength to support the two printing units 2. The guide rod 4 is formed to have a shaft length longer than the width of the recording paper A to be conveyed, and its shaft end is fixed to a member such as a housing of the ink jet recording apparatus 1 (not shown). The guide rod 4 is installed in parallel with the recording surface of the recording paper A at a predetermined distance along the width direction of the recording paper A whose longitudinal axis crosses the direction in which the recording paper A is conveyed. ing. Therefore, the printing unit 2 and the balancer unit 3 are supported by the guide rods 4, and the printing unit 2 and the balancer unit 3 are moved with respect to the recording paper A being conveyed while maintaining a constant distance from the recording surface thereof. Guided movement in the cross direction.
[0016]
A drive pulley 6 is installed on one side of the recording sheet A to be conveyed above the guide rod 4, and a driven pulley 7 is rotatable on the other side. It is installed in. The rotation center of the driving pulley 6 is connected to the output shaft of the motor 5, and the motor 5 has a predetermined output capable of driving the loads of the two printing units 2.
[0017]
A timing belt 8 is wound around the driving pulley 6 and the driven pulley 7 with a predetermined tension. Therefore, the linear portion of the timing belt 8 located between the driving pulley 6 and the driven pulley 7 is directed in the direction intersecting the recording paper A to be conveyed, like the guide rod 4. The timing belt 8 is a toothed belt having a predetermined pitch on the inner periphery thereof, and a similar pitch on the outer periphery of the drive pulley 6 and meshed with each other. Therefore, slippage between the timing belt 8 and the driving pulley 6 is eliminated, and the printing unit 2 and the balancer unit 3 moved by the timing belt 8 have sufficient timing, speed, and positioning accuracy to start and end the movement. To ensure that
[0018]
The printing unit 2 is in contact with the guide rod 4, is supported so as to be movable in the longitudinal direction of the shaft, and is mounted on a predetermined portion of the timing belt 8. The printing unit 2 has a nozzle hole for ejecting ink, and is in tight contact with the guide rod 4 so that the nozzle hole maintains a posture facing the recording paper A. The printing unit 2 is configured to print using four colors of C (cyan), M (magenta), Y (yellow), and K (black), and has a built-in tank storing inks of these colors. I have. That is, the printing unit 2 raises the pressure in this chamber by energizing the piezoelectric vibrator and the heating element provided in the pressure generating chamber at an appropriate timing, and causes the ink supplied into the chamber to generate pressure in the pressure generating chamber. The recording paper A is configured to be ejected toward the recording paper A from a nozzle hole communicated with the recording paper A, to cause ink droplets to adhere to a predetermined portion of the recording paper A, and to print on the recording paper A.
[0019]
The balancer unit 3 has substantially the same mass as the printing unit 2, is similarly slid on the guide rod 4 as the printing unit 2, and is supported so as to be movable in the axial longitudinal direction. The balancer unit 3 is mounted on the timing belt 8 so that the position occupied by the printing unit 2 and the position occupied by the printing unit 2 are always symmetric with respect to the center of the recording paper A in the width direction. That is, in the linear portion of the timing belt 8, the balancer unit 3 is mounted on a linear portion opposite to the linear portion to which the printing unit 2 is connected. The center line of the width is set as a symmetrical line, and the position occupies a position symmetrical to the position where the printing unit 2 is mounted. For example, when the center line of the width of the recording paper A coincides with the center of the linear portion of the timing belt 8, the location where the printing unit 2 is mounted on the timing belt 8 and the location where the balancer unit 3 is mounted are: In the outer periphery of the timing belt 8, the positions of the timing belts are advanced by half a circle.
[0020]
Therefore, when the printing unit 2 occupies one position in the width direction of the recording paper by the timing belt 8 with respect to the recording paper of various sizes which can be printed by the ink jet recording apparatus 1, the balancer unit is always used. 3 will occupy the position on the other side. That is, when the timing belt 8 is fed and moved in the length direction, the printing unit 2 and the balancer unit 3 are moved in the opposite directions by the same distance as the sent length. Therefore, the printing unit 2 is moved in a range indicated by an arrow marked with A1 in FIG. 1, and the balancer unit 3 is moved in a range indicated by an arrow marked with A2 in FIG. You. For example, in one main scan, when the output shaft of the motor 5 is rotated clockwise by the energization control of the motor 5 and the driving pulley 6 is rotated clockwise, the timing belt 8 is fed clockwise. The printing unit 2 and the balancer unit 3 mounted on the symmetrical portion of the timing belt 8 are moved from one side in the width direction of the recording paper A to the other side at the same timing, and are stopped. . In the other main scanning, when the output shaft of the motor 5 is driven to rotate counterclockwise and the driving pulley 6 is rotated counterclockwise, the timing belt 8 is moved counterclockwise to move the printing unit 2 and the balancer unit 3. Are moved from the other side of the recording paper A to one side and stopped at the same timing. As described above, when the printing unit 2 and the balancer unit 3 are moved, the moving range is from the position on one side in the width direction of the recording paper A to the position on the other side.
[0021]
As described above, the printing unit 2 and the balancer unit 3 are supported by the single guide rod 4 and are configured to move symmetrically by the single timing belt 8, so that both the units 2 and 2 are printed at the time of printing. When the movement of the unit 3 is started and stopped, the vibration due to the inertia of the two units 2 and 3 can be offset, and as a result, the vibration can be suppressed or prevented. That is, since these two units 2 and 3 are mounted on the same timing belt 8 and are moved in opposite directions, the timing at which the movement of both units 2 and 3 starts and ends is synchronized, The moving speed is also the same. For this reason, the magnitude of the amount of inertia accompanying the start or end of the movement of both units 2 and 3 becomes the same, and the force for moving each unit 2 and 3 and the reaction due to the application of this force The forces are the same and the directions of the forces are opposite to each other. For this reason, the generation timings of the vibrations of the units 2 and 3 are synchronized, and the amplitude wavelengths of the vibrations generated in the units 2 and 3 have phases opposite to each other. By transmitting the vibrations having the opposite phases to each other via the guide rod 4 and the timing belt 8, the two vibrations cancel each other out, and the vibrations are attenuated or eliminated. As a result, vibrations generated from the printing unit 2 during printing can be suppressed or prevented. Therefore, according to this configuration, it is possible to reduce or avoid discomfort to the user and to affect the print quality, thereby improving the performance of the inkjet recording apparatus 1. That is, the quietness of the ink jet recording apparatus 1 having a low operation sound at the time of printing is maintained, and a comfortable feeling of use can be obtained.
[0022]
In addition, the printing unit 2 and the balancer unit 3 are mounted at symmetrical positions of the timing belt 8 so that the two units 2 and 3 are synchronized at the same timing and at the same speed in opposite directions. It is not necessary to separately provide a dedicated mechanism for moving the recording medium, and the configuration of the inkjet recording apparatus 1 can be simplified. That is, the space for providing the dedicated mechanism is reduced, the weight is not increased, and the weight and size of the inkjet recording apparatus 1 can be reduced.
[0023]
Next, a second embodiment of the present invention will be described. In the second embodiment, the balancer unit 3 is a second printing unit 9 provided with a printing function, so that printing can be performed by one main scanning operation in which both printing units 2 and 9 are moved. The required area is increased to reduce the time required for printing on one sheet of recording paper A. Note that members having the same configurations as those in the first embodiment are denoted by the same reference numerals, and description thereof will be simplified.
[0024]
That is, in the ink jet recording apparatus 1, as shown in FIG. 2, the balancer unit is the second printing unit 9 configured similarly to the other printing unit 2, and the printing control of both units 2, 9 is performed. Are printed in cooperation with each other.
[0025]
Each of the first printing unit 2 and the second printing unit 9 is subjected to printing control in accordance with its assigned printing area, so that the printed areas do not overlap. For this reason, the first printing unit 2 is moved by a single main scan to print the upstream printing area in the transport direction of the recording paper A, and the second printing unit 9 is moved to The printing area downstream of the printing area by the printing unit 2 can be printed simultaneously. Accordingly, the printing unit 2 moves the range indicated by the arrow marked with B1 in FIG. 2, and the second printing unit 9 moves the range indicated by the arrow marked with B2 in FIG. The movement direction is the opposite direction, and the timing of starting and ending the movement and the movement speed are the same.
[0026]
In this way, the area that can be printed in one main scan by moving both printing units 2 and 9 is expanded to two areas along the transport direction of the recording paper A by both printing units 2 and 9. Therefore, the number of main scans per sheet can be reduced, and the recording speed of the inkjet recording apparatus 1 can be improved. Since the printing direction of each of the printing units 2 and 9 is always set to the opposite direction, the printing operations of the printing units 2 and 9 are prevented from interfering with each other, and the printing quality can be improved. It becomes.
[0027]
In addition to this, in the first embodiment, the printing unit 2 is provided on one side and the balancer unit 3 is provided on the other side. Since the ink in the unit 2 is consumed and its mass changes, and the other balancer unit 3 maintains the same mass, the left and right balance is slightly unbalanced. On the other hand, in the second embodiment, the inks in the left and right printing units 2 and 9 are consumed almost equally, and the masses of the two printing units 2 and 9 can be maintained almost the same. It can be avoided beforehand.
[0028]
In addition, since the printing area assigned to each printing unit 2, 9 per recording sheet A is reduced, the load on each printing unit 2, 9 is reduced, and the durability can be improved. In addition, according to this configuration, since the two printing units 2 and 9 are provided, the amount of ink prepared in advance as the ink jet recording apparatus 1 is increased. Therefore, the maximum number of printable sheets can be increased without replacing or replenishing the ink in the printing units 2 and 9, and the continuous printing performance can be improved. On the other hand, when the same number of sheets as before is set as the maximum number of printable sheets, the ink tank capacity can be reduced, and the size and weight of each of the printing units 2 and 9 can be reduced. As a result, the inertia of each of the printing units 2 and 9 is reduced by the reduction in size and weight, so that the effect of suppressing or preventing vibration can be further promoted.
[0029]
In the second embodiment, the two printing units 2 and 9 are configured to print using the four colors indicated by CMYK. However, the present invention is not limited to this. And the other printing unit 9 may print using the two colors YK. According to this configuration, the number of colors assigned to each of the printing units 2 and 9 is reduced, so that the number of ink tanks in each of the printing units 2 and 9 is reduced, and the weight of each of the printing units 2 and 9 is reduced. Can be. As a result, the inertia of each of the printing units 2 and 9 is reduced, so that the suppression or prevention of vibration can be further promoted. On the other hand, when the mass of each of the printing units 2 and 9 is the same as that in the case of four colors, the capacity of the ink tank of each of the printing units 2 and 9 can be increased. As a result, the maximum number of printable sheets can be increased, and the performance of continuous printing can be improved. In addition, even if two printing units 2 and 9 are used, control for printing by each printing unit 2 and 9 can be easily assembled. That is, when the two printing units 2 and 9 perform printing in four colors, respectively, the information amount that is processed is about twice or more per unit time as compared with the case where one printing unit 2 performs printing in four colors. Then, control for sending print data to both printing units 2 and 9 is required. On the other hand, when each of the printing units 2 and 9 prints two colors, the amount of information to be processed can be reduced by the reduced number of colors, so that the control configuration can be simplified.
[0030]
In addition, the inkjet recording apparatus 1 may be configured to print using a total of six colors obtained by adding two intermediate colors to four colors of CMYK, or may be configured to print using a larger number of colors. In this case, the colors shared by the units 2 and 9 may be freely combined. In addition, when the number of colors to be used is an odd number, the configuration may be such that both printing units 2 are provided with ink tanks of the same color, or one of the printing units 2 is provided with a dummy weight. Therefore, even in the case of the configuration using these multiple colors, the configuration can be such that the ink tanks of each color are dispersed in the two printing units 2 and 9, so that compared to the configuration in which the single printing unit 2 is provided. Thus, it is possible to suppress a sudden increase in the mass of each of the printing units 2 and 9. Accordingly, since the inertia of each printing unit 2 does not need to be sharply increased, the effect of suppressing or preventing vibration can be sufficiently obtained.
[0031]
Next, a third embodiment will be described. In the third embodiment, by setting the printing boundaries of the printing units 2 and 9 on the center line in the width direction of the recording paper A, the printing area to which the printing units 2 and 9 move and are in charge is set. The time required for one main scanning operation is reduced.
[0032]
That is, as shown in FIG. 3, the ink jet recording apparatus 1 has the same configuration as that of the ink jet recording apparatus 1 according to the above-described second embodiment, but differs in the usage form. In the ink jet recording apparatus 1, the printing area of each of the printing units 2 and 9 is defined by the center line C0 of the recording sheet A shown in FIG. Is the region up to the limit position in. Therefore, the printing unit 2 is moved in the range indicated by the arrow marked C1 in FIG. 3, and the second printing unit 9 is moved in the range indicated by the arrow marked C2 in FIG. The movement direction is the opposite direction, and the timing of starting and ending the movement and the movement speed are the same.
[0033]
According to the third embodiment, the effect of canceling vibrations can be enhanced. That is, in the above-described first and second embodiments, the movement start and stop positions of the printing unit 2 and the balancer unit 3 or both of the printing units 2 and 9 are always along the width direction of the recording paper A. The left and right sides of the full width of the paper are in opposite positions. On the other hand, in the third embodiment, the movement start and stop positions of the printing units 2 and 9 correspond to the right and left opposite positions along the width direction and the center position in the width direction. Will be alternated and repeated. As described above, the positions at which the movement of the units 2 and 9 is started and stopped are located at the center at least once in two main scans in which the units 2 and 9 are moved. For this reason, the positions at which the vibrations accompanying the start and stop of the movement of the units 2 and 9 are located close to each other, so that the distance over which the two vibrations are transmitted is reduced, and the two phases have opposite phases. The effect of canceling out the damped vibrations and damping them can be enhanced. In addition, the printing direction of each printing unit 2, 9 is always the opposite direction, and each printing unit 2, 9 is separated from each other at the center in the width direction in which it moves. 9 can be further prevented from interfering with each other, and the printing quality can be further improved.
[0034]
In addition, in any recording paper A, since the printing area of the recording paper A is divided at the center and shared by the two printing units 2 and 9, each printing unit 2 and 9 The moving distance is shortened, and the time required for one main scanning operation for moving both printing units 2 and 9 is shortened. For this reason, the interval between the sub-scanning operations for transporting the recording sheet A is shortened, and the feed speed of the recording sheet A is increased. As a result, a sense of speed can be obtained in the printing operation as a whole, so that usability can be improved. At the same time, depending on the recording paper A, the printing operation can be made more efficient and faster, and the printing performance can be improved while suppressing or preventing vibration. That is, for example, in the operation of creating a Christmas card or a New Year's postcard, there are many opportunities to print on a sheet smaller than the normal recording sheet A and to print a large number of sheets at once. According to the third embodiment, since printing is performed on a small-sized sheet whose sheet width is smaller than that of a normal sheet, the feature that the sheet feeding speed is increased is promoted, and the printing time required for each sheet is reduced. Thus, the printing operation can be performed efficiently and quickly.
[0035]
It should be noted that the drive control of both printing units 2 and 9 may be configured to be switched by selecting either the second embodiment or the third embodiment. The printing method can be adopted as appropriate. That is, for example, when the recording paper A to be printed is set and conveyed in a direction in which the recording paper A to be printed is vertically long and has a small width, the drive control of the second embodiment is changed to the third control. The control may be switched to the drive control of the embodiment. Therefore, in this case, the printing operation can be performed quickly by utilizing the feature of the third embodiment in which the paper feeding speed is increased.
[0036]
In each of the above-described embodiments, the timing belt 8 is used as a member for moving the units 2, 3, and 9, but a wire may be used. In short, it has a predetermined flexibility, and when it is stretched over the two pulleys 6 and 7, a linear portion can be secured between the two pulleys 6 and 7. An integral annular member having a small amount of extension when it is moved may be used.
[0037]
【The invention's effect】
According to the first aspect of the present invention, the balancer unit having the same mass as the printing unit is moved at the same timing and at the same speed in the direction opposite to the printing unit, so that the printing unit is moved to perform printing. Vibration generated at the time can be suppressed or prevented, and user's feeling of use and printing quality can be improved. That is, the vibration generated when the printing unit starts and stops moving can be attenuated or eliminated by canceling out the vibration generated by the balancer unit that has started and stopped moving in the opposite direction at the same timing. Can suppress or prevent vibration.
[0038]
According to the second aspect of the present invention, since the printing unit and the balancer unit are mounted at symmetric positions of the belt member and are reciprocated by driving the motor, the two units are synchronized with each other and at the same time. It is not necessary to separately provide a dedicated mechanism for driving at the same speed in the opposite direction, and the configuration of the inkjet recording apparatus can be simplified.
[0039]
According to the third aspect of the present invention, since the balancer unit is used as the second printing unit and the two printing units are linked to perform printing, an area to be printed by both printing units can be enlarged. The recording speed of the recording device can be improved.
[0040]
According to the fourth aspect of the present invention, the area to be printed on the recording paper is divided at the center and divided into two printing units, so that the printing area assigned to each printing unit is reduced. For this reason, the distance over which each printing unit moves is reduced, and the time required for main scanning can be reduced. As a result, the time for main scanning is reduced, and the speed of sub-scanning for transporting the recording paper is relatively increased, so that the time required for printing can be reduced.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a main part of a first embodiment of the present invention.
FIG. 2 is a perspective view showing a main part of a second embodiment of the present invention.
FIG. 3 is a perspective view showing a main part of a third embodiment of the present invention.
FIG. 4 is a perspective view showing a main part of a conventional configuration example.
[Explanation of symbols]
1 inkjet recording device 2 printing unit
3 Balancer unit 4 Guide rod
5 Motor 6 Drive pulley
7 Follower pulley 8 Timing belt
9 Second printing unit A Recording paper
A1, B1, C1 Print unit movement range
A2 Range of movement of balancer unit
B2, C2 Moving range of the second printing unit
C0 Center line of recording paper A

Claims (4)

An endless belt member that is arranged to face the recording paper to be conveyed and that can reciprocate in a direction that intersects the conveyance direction of the recording paper; and a print that is mounted on the belt member and prints on the recording paper. In an ink jet recording apparatus comprising a unit,
An ink jet recording apparatus comprising a balancer unit mounted on the belt member at a position symmetrical to the printing unit with respect to the center of the belt member and having the same mass as the printing unit. 2. The ink jet recording apparatus according to claim 1, wherein the endless belt member is wound around pulley members provided on both sides of the recording paper, and one of the pulley members is driven to rotate by a motor. The inkjet recording apparatus according to claim 1, wherein the balancer unit is a second printing unit that prints in cooperation with the printing unit. 4. The ink jet recording apparatus according to claim 3, wherein a print area assigned to the print unit and the second print unit is an area divided right and left with a center line in a width direction of the recording paper as a boundary.

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