JPH1158789A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a print waiting time caused by the recovery operation of a print head. SOLUTION: First and second carriages 7, 8 are inserted movably into a single guide rod. A print head 5 carried on the first carriage 7 jets black ink while a print head 6 carried on the second carriage 8 has a plurality of head parts for jetting color inks. During print operation using the head part carried on the first carriage 7, recovery operation is performed for the head part carried on the second carriage 8 by a suction means 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus having a plurality of carriages each having a print head having at least one head unit.

[0002]

2. Description of the Related Art In general, a color ink-jet printer has a print head having four color heads of black, yellow, magenta and cyan arranged in parallel on a single carriage, and the carriage is moved in the width direction of the print medium. Printing is performed by scanning.

[0003] In such an ink jet printer, the head portion of another color is exposed to the atmosphere during black printing, causing problems such as clogging and sticking due to drying of the ink. It is common to perform idle discharge as a recovery operation and perform ink suction from the head part of another color even at the start of printing or at the time of artificial suction recovery operation. Longer, and with such a recovery action,
In spite of not printing, ink must be consumed, which is extremely uneconomical. In addition, it is necessary to always drive a heavy carriage having four head units mounted thereon, and therefore an expensive and large carriage driving motor is required.

Therefore, as described in, for example, Japanese Patent Application Laid-Open No. 1-222151, a plurality of carriages each having at least one head are provided, and the individual carriages including the heads are separately driven and controlled. An ink jet printer has been proposed in which, when a head mounted on one carriage is used, the other carriage is kept in a standby state and unnecessary wasteful ejection is not required.

[0005]

However, in such an ink-jet printer, the recovery operation is generally performed by judging whether or not printing has been performed for a certain period of time (for example, three days) by the head unit. For example, each time a print start command is issued for a head unit on a plurality of carriages, a determination is made and a recovery operation is performed or omitted. Therefore, even when the recovery operation can be omitted for the head unit on one carriage, when the head unit on another carriage needs the recovery operation, the waiting time due to the recovery operation before printing is required. There is a problem that it becomes longer.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a printing apparatus capable of reducing a waiting time due to a recovery operation.

[0007]

According to the first aspect of the present invention, there are provided a plurality of carriages on which a print head having at least one head portion is mounted, a carriage driving means for driving the carriage, the print head and the carriage driving means. A print control unit that controls printing on a print medium associated with a printing device, comprising a recovery unit that has a suction cap and suctions ink by bringing the suction cap into contact with a nozzle surface of a head unit of a print head, The print control means and the recovery means operate independently for each carriage so that a recovery operation is performed on a head part on another carriage during printing by a head part on one carriage.

According to the first aspect of the present invention, the printing control means and the recovery means perform a recovery operation on the head part of the print head on another carriage during printing by the head part of the print head on one carriage. As is done, the print head is operated independently for each carriage. Therefore, a recovery operation is performed on the head portion of the print head on another carriage by effectively utilizing the printing time of the head portion of the print head on one carriage, and as a result, printing on the other carriage is performed. At the time of printing by the head portion of the head, the head portion is in a printable state without performing the recovery operation, and the waiting time for the recovery operation is reduced.

According to a second aspect of the present invention, there is provided the printing apparatus of the first aspect, further comprising non-use determining means for determining whether or not a head portion of each of the print heads has been unused for a predetermined period of time. The print control unit and the recovery unit are operated for each carriage based on a signal from the non-use determination unit based on a signal input.

According to the second aspect of the present invention, it is determined by the non-use determining means whether or not the head portion of each print head is unused for a predetermined period, and based on the input of the print start signal,
For each carriage, the print control unit and the recovery unit are operated based on the signal from the non-use determination unit. That is, the recovery operation is performed on the head portion of the print head that has been determined to be unused for a certain period by the non-use determination unit.

According to a third aspect of the present invention, in the printing apparatus of the first or second aspect, the carriage has first and second carriages, and the first and second carriages have a single guide rod. The first and second protective caps for the print heads of the first and second carriages are provided independently on one side of the print medium transport path.

According to the third aspect of the present invention, the print heads of the first and second carriages are independently provided by the first and second protective caps provided on one side of the transport path of the print medium. Each is capped. And the first
When printing is performed by the print head of the second carriage, the print head of the second carriage is capped by the second protective cap, and drying of the nozzle surface is prevented.

According to a fourth aspect of the present invention, in the printing apparatus of the first or second aspect, the carriage has first and second carriages, and the first and second carriages are provided with a single guide. A first protective cap for the print head of the first carriage is provided on one side of the transport path of the print medium, and a second protective cap for the print head of the second carriage is provided on the other side. Two protective caps are provided with the recovery device.

According to the fourth aspect of the present invention, when printing is being performed by the print head of the first carriage, the second print is performed.
The print head of the carriage is capped by the second protective cap to prevent the nozzle surface from drying. Also,
When printing is being performed by the print head of the second carriage, the print head of the first carriage is capped by the first protective cap to prevent the nozzle surface from drying.

According to a fifth aspect of the present invention, in the printing apparatus of the first or second aspect, the first and second carriages are movably inserted into first and second guide rods provided in parallel, respectively. Have been.

According to the fifth aspect of the present invention, the first and second carriages are movably inserted into the first and second guide rods provided in parallel, respectively. The second carriage does not interfere at all, and the degree of freedom in controlling printing by each print head is significantly increased.

According to a sixth aspect of the present invention, in the printing apparatus according to any one of the second to fifth aspects, the print head mounted on the first carriage ejects black ink, while the second print head ejects black ink. A print head mounted on the carriage has a plurality of head units for discharging color ink, and the print control unit is configured to receive a signal from a facsimile.

According to the sixth aspect of the invention, the print head of the first carriage is controlled based on the signal from the facsimile, and the facsimile information is printed on the print medium with black ink. In addition, since a print head that ejects frequently used black ink is mounted on the first carriage, and a print head that has a plurality of head units that ejects color ink is mounted on another second carriage, During printing by the head unit on the first carriage, a recovery operation is performed on the head unit on the second carriage, and when shifting to color printing, printing is performed without waiting time due to the recovery operation.

According to a seventh aspect of the present invention, in the printing apparatus of the sixth aspect, the recovery means performs a recovery operation of the print head mounted on the first carriage and a print head mounted on the second carriage. This is given priority over the recovery operation.

According to the seventh aspect of the present invention, the recovery operation of the print head that ejects the most frequently used black ink is prioritized, and the recovery operation of the print head on the second carriage is not completed. Then, printing by the head unit on the first carriage is started.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic perspective view showing the overall configuration of an ink jet printer as a printing apparatus according to the present invention.
In FIG. 1, an ink jet printer 1 has a cylindrical platen roller 3 rotatably supported on a printer frame 2 by a rotation shaft (not shown) extending in the left-right direction.
Having. The platen roller 3 conveys the printing paper 4 (printing medium) supplied from a paper feeding cassette or a manual paper feeding unit while facing the first and second print heads 5 and 6, and is a so-called paper feed. It constitutes a part of the mechanism LM. The first and second print heads 5, 6 are
An ink jet type having a nozzle for discharging ink droplets on the printing paper 4 and performing a printing operation on the printing paper 4, the paper feeding mechanism LM drives the paper feeding mechanism LM to print the printing paper 4.
LF motor 124 (see FIG. 4) as a paper feed motor for transporting the paper.

The printing paper 4 is supplied in the direction of arrow A from a paper supply port (not shown) at the rear of the printer frame 2, is fed in the direction of arrow B by rotation of the platen roller 3, and is supplied to the paper discharge port (see FIG. (Not shown) is discharged in the direction of arrow C. In front of the platen roller 3, first and second carriages 7, 8 on which first and second print heads 5, 6 are mounted are provided movably along the axis of the platen roller 3. .

The carriages 7, 8 are provided with print heads 5,
6 and ink cartridges 9A, 9B, 9C and 9D containing ink supplied to the print heads 5 and 6, respectively, are detachably mounted. In this example, the print head 5 and the ink cartridge 9A having a head for one color of black are provided on the first carriage 7 in the second carriage.
Carriage 8 includes yellow, cyan, and magenta.
A print head 6 having head portions 6A, 6B, 6C for colors and ink cartridges 9B, 9C, 9D are mounted respectively.

The first and second carriages 7, 8 are
Carriage shaft 1 whose both ends are supported by frame member 10
The carriage shaft 11 is mounted on the printer frame 2 such that the carriage shaft 11 is parallel to the axis of the platen roller 3 while being slidably fitted to the guide rod 1 and supported by the frame member 10. The engaging portions 7a and 8a of the carriages 7 and 8 are guided by a guide rail 12 extending parallel to the carriage shaft 11. Thus, the print heads 5 and 6 mounted on the carriages 7 and 8 can reciprocate by sliding along the axis of the platen roller 3.

The carriages 7, 8 are fixed to a part of the timing belts 13, 14,
The carriage mechanism CM is formed by winding the first and second CR motors 15 and 16 around the timing pulleys (not shown).
(Carriage drive motor). Therefore,
When the CR motors 15 and 16 are rotationally driven, the first and second carriages 7 and 7 are driven via the carriage mechanism CM.
8 reciprocates in a printing area where printing is performed on the printing paper 4. Also, the carriage mechanism CM
The CR motors 15 and 16 are configured to move between the print area and a recovery area where a recovery operation is performed by a suction cap 21, a suction pump 22, and a wiper member 24, which will be described later.

The CR motors 15 and 16 are of a type capable of controlling the direction of rotation and the amount of rotation.
/ AC motor is employed. As shown in FIG. 2, a linear encoder 51 provided along the running direction of the carriages 7 and 8 and having black vertical stripes printed on a transparent PET film, and the linear encoder 51 provided on the carriages 7 and 8 side. First and second photo sensors 52 and 53 (for example, transmission type photo interrupters) for detecting the positions of the first and second carriages 7 and 8 based on the first and second carriages 7 and 8 are used as first and second position detecting means 54 and 55. And the scanning amount of the carriages 7 and 8 is
It is determined by counting the vertical stripes of the linear encoder 51 by 2 and 53. Then, the reciprocating scanning width of the carriages 7, 8 is calculated based on the signals from the first and second position detecting means 54, 55. In addition, DC /
In addition to the AC motor, a pulse motor of open loop control can be employed, and in this case, the position detecting means can be omitted.

On the right side of the print area corresponding to the platen roller 3, there is formed a recovery area provided with a purge mechanism RM for recovering from non-ejection of the print heads 5, 6 or ejection failure. . The reason why such a purge mechanism RM is provided is that the ink jet print heads 5 and 6 cause ejection failure due to the occurrence of bubbles inside the ink or the drying of the ink during use.
This is for restoring this to a favorable ejection state.

The purge mechanism RM includes print heads 5 and 6.
A suction cap 21 that can move between a protruding position that protrudes into the movement path of the print head 5 and a standby position that retreats from the movement path of the print heads 5 and 6, and that is in close contact with the nozzle surfaces of the print heads 5 and 6 at the protruding position; At the protruding position, when the print heads 5 and 6 are covered with the suction cap 21, the suction head 22 generates a negative pressure and suctions ink in the print heads 5 and 6 through the suction cap 21. A suction unit 23 is provided.

Adjacent to the suction means 23, a wiper member 24 movable relative to the print heads 5, 6 so as to wipe the nozzle surfaces of the print heads 5, 6 on the print area side,
On the opposite side, protective cap devices 25 and 26 are provided to cover the nozzle surfaces of the print heads 5 and 6 when printing is not performed and to prevent evaporation of the ink and avoid drying of the nozzle surfaces.

The wiper member 24, the suction cap 21 and the suction pump 22 are associated with driving means having a cam member 27 which is driven to rotate, so that the wiper member 24 advances and retreats, the suction cap 21 advances and retreats, and the suction pump 2 moves.
2 is configured to be controlled by the rotation of the common cam member 27.

Therefore, the cam member 27 is driven to rotate at a constant timing, so that the suction cap 21 is capped, the suction pump 22 sucks ink, and the wiper member 24 wipes the nozzle surfaces of the print heads 5 and 6. Are sequentially performed, and the ink sucked by the suction pump 22 is discharged to the waste ink tank 31 via the suction pump 22 and is adsorbed by the adsorbent 32 in the waste ink tank 31.

The protective cap devices 25 and 26 are provided with a first
And casings 43 and 44 that support the protective caps 41 and 42 can slide and rotate on guide rods 45 that extend in parallel with the moving directions of the carriages 7 and 8. It is supported to be.

Since capping by the protective caps 41 and 42 is performed in the same manner, capping by the protective cap 41 will be described with reference to FIG. FIG.
As shown in FIG.
When the carriage 7 moves outside the printing area, an engaged portion 43a for engaging with the engaging portion 7b of the carriage 7 and slidingly moving integrally with the carriage 7 protrudes forward. Have been. When the carriage 7 moves from the printing area to the recovery area, the engaging portion 7b of the carriage 7 engages with the engaged portion 43a of the casing 43, so that the protective cap 41 slides following the movement of the carriage 7. Moving. During this sliding movement, the engaging projection 43b of the casing 43 rotates around the guide rod 45 by the action of the inclined cam surface 47, and as a result, the protective cap 41 rotates in the direction approaching the print head 5. The protective cap 41 comes into contact with the nozzle surface of the print head 5 to perform capping. Thereafter, when the carriage 7 moves in the print area direction again, the protective cap 41 moves away from the print head 5 while moving to the print area side by the urging force of the spring member 46, and when the carriage 7 comes out of the recovery area, the initial state. Return to the state.

Next, the control section of the ink jet printer 1 according to the embodiment will be described with reference to the block diagram of FIG.

This control section is mainly composed of a CPU 101 which is a well-known arithmetic processing unit. The CPU 101 is connected to a host computer 103 such as a personal computer via a Centro interface 102, receives a print command from the host computer 103, and executes various prints according to the command. CPU1
Numeral 01 is connected to a telephone line 105 via a modem 104, receives a facsimile signal, and executes printing in accordance with the signal.

The CPU 101 has an operation panel 106
Are connected, and a ROM 107 and a RAM 108 are connected through an address bus and a data bus.
The operation panel 106 is for setting various parameters such as a paper size and displaying them. ROM1
Reference numeral 07 stores various programs necessary for controlling the inkjet printer 1. RAM 108
Is for temporarily storing print data transferred from the host computer 103 and various numerical values necessary for controlling the inkjet printer 1.

The CPU 101 has a first control system which forms two control systems via an address bus and a data bus.
And the second gate arrays 111 and 112 are connected in parallel, and the gate arrays 111 and 112 are connected to the print heads 5 and 6 (6A, 6A,
6B, 6C) are controlled independently.

Then, the CPU 101 controls the print heads 5,
6 and the printing paper 4 associated with the CR motors 15 and 16
Print control means 101A for controlling the printing of the print heads, and non-use determining means 101B for determining whether or not the heads of the print heads 5 and 6 have been unused for a certain period of time. On the basis of a signal from the non-use determining unit 101B for each of the carriages 7 and 8, the printing control unit 101A and the suction unit 2 serving as a recovery unit.
3 (recovery means) are operated. Therefore, the nonuse determining unit 101B determines whether or not the heads of the print heads 5 and 6 are not used for a certain period of time. The print control unit 101A and the cam member 27 of the suction unit 23 are operated based on the signal from the use determination unit 101B. It also functions as a facsimile output device, and black ink is used more frequently than other inks.
The recovery operation of the print head 5 mounted on the carriage 7 is prioritized over the recovery operation of the print head 6 mounted on the second carriage 8.

Therefore, during printing by the head of the print head 5 on the first carriage 7, that is, during printing with frequently used black ink, the heads 6 A to 6 A of the print head 6 on the second carriage 8 are printed. The print heads 5 and 6 can be operated independently for each of the carriages 7 and 8 so that the recovery operation is performed on 6C, so that the waiting time due to the recovery operation is eliminated particularly in color printing. It becomes possible.

The gate arrays 111, 112
Are supplied with a black encoder signal and a color encoder signal, respectively.
5,116.

The CPU 101 controls the driving of the LF motor 124 and the CR motors 15 and 16 via the LF driving circuit 121 and the CR driving circuits 122 and 123.

Further, the CPU 101 has an origin sensor 125 for detecting that the suction pump is at the origin position, and a paper / paper for detecting the leading end of the newly supplied printing paper 4.
A signal from the sensor 126 is input.

The operation of the ink jet printer 1 configured as described above will be described.

First, in the ink jet printer 1, usually, the print heads 5, 6 are at the standby position in a state of being covered with the protective caps 41, 42 in the recovery area.
When print data is input, printing is performed.

That is, when a color print signal is input to the CPU 101, the print paper 4 is supplied between the platen roller 3 and the print heads 5, 6, and the CR motors 15, 1
By the operation of 6, the print heads 5, 6 are moved from the standby position to the print start position. At this time, the protective cap 4
1,42 are retracted. As a result, the print heads 5, 6
Are reciprocated in the printing area while ejecting ink based on the printing data, so that color printing is performed on the printing paper 4.

When there is no print data to be printed in the print data memory of the RAM 108 and the printing is completed, the print heads 5 and 6 are moved from the printing end position to the standby position, and are moved by the protection caps 41 and 42 which have been advanced. This prevents the nozzle surfaces of the print heads 5 and 6 from drying while being covered and not used.

The facsimile signal and the black print signal are C
When the input is made to the PU 101, only the print head 5 moves to the print area, the print head 6 remains in the recovery area and is kept in a standby state in a state covered with the protective cap 42, and the nozzle face of the print head 6 is dried. Is prevented.

That is, the printing paper 4 is supplied between the platen roller 3 and the printing head 5, and the printing head 5 is moved from the standby position to the printing start position by the operation of the CR motor 15. At this time, the protection cap 41 is retracted. As a result, the print head 5 is reciprocated in the print area while ejecting ink based on the print data, so that black printing is performed on the print paper 4.

When the printing is completed, the print head 5
Is moved from the printing end position to the standby position, and is covered with the protective cap 41 that has been advanced, so that the nozzle surface of the print head 5 is prevented from drying during use.

Further, when the purge switch on the operation panel is operated and a purge command is input according to the user's judgment, a purge process for operating the purge mechanism RM is started, and a suction operation program is executed. That is, by driving the carriage mechanism CM by the CR motors 15 and 16, the print heads 5 and 6 are moved from the standby position to a purgeable position facing the suction cap 21.
The cam member 27 makes one rotation, and the suction cap 21 is attached to one of the print heads 5 and 6 at the predetermined purge position.
In addition, the operation of bringing the wiper member 24 into and out of contact and the suction / discharge operation by the suction pump 22 are performed. Then, the respective head units to which the purge command is input are sequentially moved to the purge position, and the same operation is repeated. Here, the suction operation includes the operation of bringing the suction cap 21 into close contact with the nozzle surface and sucking the ink from the print heads 5 and 6 by the suction pump 22, and the operation of the suction pump 22 by separating at least a part of the suction cap 21 from the nozzle surface. , A so-called idle suction operation of sucking ink from inside the suction cap 21 is included.

Next, the flow of printing processing at the time of starting printing in the ink jet printer 1 will be described with reference to FIG.

When the print data is input and the printing process is started, the recovery operation of the print head 5 (black head) mounted on the first carriage 7 is performed by the print head 5 mounted on the second carriage 8. In order to give priority to the recovery operation of the 6 (color head), it is first determined whether or not the first print head 5, which is the black head, has been unused for three days, for example (step S1). And if not used for 3 days, the first
The purge process of the print head 5 is started in the same manner as described above (step S2). If it is not used for three days, it is considered that the purge process is not necessary for the first print head 5, so the process immediately proceeds to step S3. Then, it is determined whether or not the second print head 6 has been unused for three days.

If the second print head 6 has not been used for three days, the purging process of the second print head 6 is started (step S4), and the second print head 6 must be unused for three days. For example, since it is considered that the purging process is not required for the second print head 6, the process immediately proceeds to step S5, and it is determined whether or not the input data includes a request for printing for the first print head 5. Is made.

If there is a print request for the first print head 5 (hereinafter referred to as a black print request), it is determined whether or not the first print head 5 is purging (step S6). If the first print head 5 is performing the purging process, black printing cannot be performed, so it is determined whether or not there is a print request (hereinafter referred to as a color print request) to the second print head 6 (step S7). On the other hand, if the first print head 5 is not performing the purging process, black printing by the first print head 5 is started (step S8), the black print request is reset (step S7), and the process proceeds to step S9. .

If it is determined in step S9 that there is a color printing request, it is determined whether the second print head 6 or the first print head 5 is performing a purge process (step S10), If the print head 6 and the first print head 5 are not under the purging process, the color print by the second print head 6 is started (step S11), the color print request is reset (step S12), and the first or the second print head 6 is reset. It is determined again whether or not there is a request for printing by the second print heads 5 and 6 (step S13). If there is a print request, the process proceeds to step S5, and the processes of steps S5 to S13 are repeated.

On the other hand, if the second print head 6 or the first print head 5 is in the purging process, color printing cannot be performed, so that the process proceeds to step S13.

The start of purging or the start of printing in steps S2, S4, S8, and S10 starts these operations. During the execution of these operations, it is possible to proceed to the next process. That is, the purging of the second print head 6 is started (step S4), and if the purging of the first print head 5 is completed or unnecessary, black printing can be started (step S8). . When the purging of the second print head 6 is completed, color printing can be started in parallel with black printing (step S11). Even if the print data is only black print, it is determined whether or not the purge of the second print head 6 is necessary, and if necessary, the second print head 6 is purged during the black print. Therefore, after that, when the color data is input within three days, the purge process can be omitted completely and printing can be started.

In general, the black ink is used more frequently than the color ink, and in particular, the print data from the facsimile is printed with the black ink. Has priority over print head 6,
Without waiting for the completion of the purge of the second print head 6, the first
The printing by the print head 5 is started. Therefore, in the case of only black printing, it can be completed quickly. In addition, since the second print head 6 is purged during black printing as described above, it is possible to eliminate a waiting time for the purge processing when shifting to color printing (not used). When the period is less than 3 days).

In the above embodiment, when the print head is not driven for three days and printing is not performed using timer means or the like, it is determined that the print head is not used, and the purge process is executed. Alternatively, the time from the previous purge operation (suction operation) is counted, and when the count value exceeds a certain value at the time of inputting the print start signal,
A purge process may be performed. In this case, if there is a purging operation, it is determined to be “used”.

In the above embodiment, the first and second protective caps 41 for the print heads 5 and 6 of the first and second carriages 7 and 8 are provided on one side of the transport path of the print paper 4. , 42 are provided independently, but the present invention is not limited to this. For example, as shown in FIG. 6, the first and second carriages 7, 8 are connected to a single guide rod (not shown). ), And movably inserted into the printing paper 4
The first protection cap 41 for the print head 5 of the first carriage 7 is provided on one side of the transport path of the first carriage 7, and the second protection cap 42 for the print head 6 of the second carriage 8 is provided on the other side. It is also possible to provide together with the wiper member 24 and the suction cap 21 which are devices. In this way, when printing is performed by the print head 5 of the first carriage 7, the print head 6 of the second carriage 8 is capped by the second protective cap 42 and Of the nozzle surface of the first carriage 7 when printing is being performed by the print head 6 of the second carriage 8.
Is capped by the first protective cap 41, so that drying of the nozzle surface of the print head 5 can be prevented. Therefore, when printing is performed by the print head of one carriage, the print head of the other carriage can be capped by the protective cap to prevent the nozzle surface of the print head from drying.

Further, as shown in FIG.
Can be applied to the first and second carriage shafts 11A and 11B movably inserted respectively. In this way, the first and second carriages 7, 8 are respectively
First and second carriage shafts 11A provided in parallel,
Since the first and second carriages 7 and 8 do not interfere at all because they are movably inserted through 11B, the degree of freedom in controlling printing by the print heads 5 and 6 can be significantly increased. In FIG. 7, the protective cap 4
Reference numerals 1 and 42 also serve as suction caps.

In the above embodiment, the first print head 5 for discharging black ink and the second print head 6 having a plurality of heads for discharging other color inks are divided. Although it is particularly advantageous when used as an output device for facsimile information, the present invention is not limited to this, and can be applied to a case where any print head has a plurality of head units. Is possible.

In the recovery operation, not only the process of sucking the ink or wiping with the wiper but also the idle discharge of discharging the ink from the print head outside the print area may be performed.

[0065]

The present invention is embodied in the form described above, and has the following effects.

According to the first aspect of the present invention, there is provided a printing control means for controlling printing on a printing medium, and a suction cap, wherein the suction cap is brought into contact with a nozzle surface of a head portion of a print head to discharge ink. The recovery means for sucking operates independently for each carriage so as to perform a recovery operation on the head part on another carriage during printing by the head part on one carriage.
During printing by the head unit on one carriage, a recovery operation can be performed on the head unit on the other carriage,
The waiting time due to the recovery operation can be reduced. In other words, the recovery operation can be performed on the head unit on the other carriage during printing by the head unit on one carriage, so that the recovery operation is performed irrespective of whether it is used for printing or not. When printing is performed on the first printing, the printing can be performed immediately without performing the recovery operation, and the waiting time due to the recovery operation can be eliminated.

According to a second aspect of the present invention, it is determined whether or not the head portion of each print head is not used for a predetermined period, and based on the result of the determination, a print start signal is input to each of the carriages. Since the print control means and the recovery means are operated respectively, the recovery operation can be performed efficiently, and all the head units can be quickly brought into a usable state.

According to a third aspect of the present invention, the first and second carriages are movably inserted into a single guide rod, and the first and second carriages are provided on one side of the print medium transport path. Since the first and second protective caps for the print head are provided independently, the print heads of the first and second carriages can be independently capped by the first and second protective caps. it can.

According to a fourth aspect of the present invention, the first and second carriages are movably inserted into a single guide rod, and the first and second carriages are disposed on one side of the print medium transport path with respect to the print head of the first carriage with respect to the print head. Since one protective cap is provided and the second protective cap for the print head of the second carriage is provided on the other side together with the recovery device, when printing is performed by the print head of one carriage, The print head of the carriage can be capped with the second protective cap to prevent the nozzle surface of the print head from drying.

According to the fifth aspect of the present invention, the first and second carriages are movably inserted into the first and second guide rods provided in parallel, respectively. Printing can be performed freely without causing interference with the carriage.

According to a sixth aspect of the present invention, a print head for ejecting black ink, which is most frequently used, is mounted on a first carriage, and a print head having a plurality of head units for ejecting color ink is provided in another second carriage. The facsimile information is printed on a print medium by black printing without driving the second carriage by controlling the head of the first carriage based on a signal from the facsimile because the facsimile is mounted on the carriage. Can be.

According to the seventh aspect of the present invention, the recovery operation of the print head which discharges the frequently used black ink is prioritized. Therefore, the print head which discharges the black ink which is frequently used is recovered first, and the color ink is recovered. By starting the black ink printing without waiting for the completion of the recovery operation for the head unit that discharges the ink, the recovery operation of the head unit that discharges the color ink can be performed by effectively using the time during the black printing. . Further, it is possible to eliminate the waiting time due to the recovery operation when shifting to color printing.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an ink jet printer which is a printing device according to the present invention.

FIG. 2 is an explanatory diagram of a position detecting means according to the present invention.

FIG. 3 is an explanatory diagram of an operation of the protective cap device according to the present invention.

FIG. 4 is a block diagram of a control system according to the present invention.

FIG. 5 is a flowchart showing a control flow according to the present invention.

FIG. 6 is an explanatory diagram of another embodiment.

FIG. 7 is an explanatory diagram of still another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink jet printer 3 Platen roller 4 Print paper 5 1st print head 6 2nd print head 6A head part 6B head part 6C head part 7 1st carriage 8 2nd carriage 11 Carriage shaft 11A 1st carriage shaft 11B Second carriage shaft 15 First CR motor 16 Second CR motor 23 Suction unit 41 First protection cap 42 Second protection cap 101 CPU 101A Print control unit 101B Nonuse determination unit 111 First gate array 112 Second gate array

Claims (7)

[Claims] 1. A plurality of carriages each having a print head having at least one head unit, carriage driving means for driving the carriage, and printing for controlling printing on a print medium associated with the print head and the carriage driving means. A printing device comprising: a control unit; and a recovery unit that has a suction cap and suctions the ink by bringing the suction cap into contact with a nozzle surface of a head unit of a print head. A printing apparatus which operates independently for each carriage so that a recovery operation is performed on a head unit on another carriage during printing by a head unit on one carriage. 2. The printing apparatus according to claim 1, further comprising a non-use determining unit configured to determine whether a head unit of each of the print heads has been unused for a predetermined period of time. 2. The printing apparatus according to claim 1, wherein the printing control unit and the recovery unit are operated based on a signal from the determining unit. 3. The carriage has a first and a second carriage, wherein the first and the second carriages are movably inserted into a single guide rod, and a transport path of the print medium. 3. The printing apparatus according to claim 1, wherein the first and second protection caps for the print heads of the first and second carriages are independently provided on one side. 4. The printing apparatus according to claim 1, wherein the carriage has first and second carriages, the first and second carriages are movably inserted into a single guide rod, and transport the print medium. Claims wherein on one side of the path a first protection cap for the printhead of the first carriage is provided and on the other side a second protection cap for the printhead of the second carriage is provided together with the recovery device. Item 3. The printing device according to Item 1 or 2. 5. The printing apparatus according to claim 1, wherein the first and second carriages are movably inserted into first and second guide rods provided in parallel, respectively. 6. A print head mounted on the first carriage discharges black ink, while a print head mounted on the second carriage has a plurality of heads discharging color ink. The printing apparatus according to claim 2, wherein the printing control unit is configured to receive a signal from a facsimile. 7. The recovery means according to claim 1, wherein the recovery means gives priority to the recovery operation of the print head mounted on the first carriage over the recovery operation of the print head mounted on the second carriage. Item 7. The printing device according to Item 6.