JP2004174823A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the weak points of a pit-in system ink jet printer that the print speed is lowered because a carriage must be moved up to an ink supplementing position. <P>SOLUTION: The time related to ink supplement is shortened by analyzing the print sequence and supplementing ink with such a scan as the moving distance of the carriage to an ink supplementing position is minimized. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
Related to an image forming apparatus.
[0002]
[Prior art]
Many conventional inkjet printers are generally called serial printers.
[0003]
A serial printer is a printer that performs printing by the following method.
[0004]
1) Printing is performed while a print head having a fixed print width is reciprocated in one direction.
[0005]
2) When printing of a certain unit is completed, the print medium or print head is moved by a fixed amount in a direction perpendicular to the printing direction.
[0006]
3) Repeat steps 1) to 2) until printing is completed.
[0007]
Conventional inkjet printers are mainly classified into the following three modes.
[0008]
1. A print head and main ink tank that are integrated or closely attached.
[0009]
2. The print head and main ink tank are separated and always connected by a tube.
[0010]
3. A printer that separates the print head from the main ink tank, and connects and replenishes it with a pipe as necessary.
[0011]
The above-described embodiments 2 and 3 have a configuration in which the print head is appropriately replenished with ink from the main ink tank separated from the print head, and has the following advantages.
-Since the main ink tank does not move together with the print head, the weight of the operating section can be reduced.
・ Since the weight of the head unit is light, the driving mechanism is simple, the cost is low, and the weight of the apparatus can be reduced.
・ Because the main ink tank is separated from the print head, it can be fixedly arranged and the capacity can be increased. For this reason, the number of ink jet printers that meet the recent demands of the market for high speed, post-durability, and low running cost in the above-described forms of 2.3 is increasing.
[0012]
Further, in the third embodiment, since there is no load and control disturbance on the head unit called a tube, the head unit can be driven stably and with high accuracy, and high quality printing can be easily performed. Further, there is an advantage that the configuration of the head unit can be simplified and the configuration can be made lighter.
[0013]
The present invention relates to the above-mentioned three aspects of the serial printer type inkjet printer.
[0014]
Hereinafter, the above three modes are referred to as a pit-in system.
[0015]
[Problems to be solved by the invention]
As described in the above prior art, the pit-in system of the present invention has many advantages as described above, but also has the following problems and disadvantages.
[0016]
In this configuration, it is necessary to periodically replenish the ink from the ink tank to the head. However, since the head unit and the ink tank are physically separated, when replenishing the ink, both are physically connected. Need to be connected to
[0017]
A common technique is to provide an ink replenishment mechanism at the end of the movable range of the head unit, and when refilling the ink, move the head unit to a position where the print replenishment mechanism is located and connect it by inserting a pipe, etc. It is to do.
[0018]
By the way, as described above, the inkjet printer according to the present invention is a serial printer, and the print head performs printing while reciprocating in a certain direction.
[0019]
Generally, a head movement other than the head movement required for printing acts as a factor in a direction disadvantageous to the printing speed. For this reason, conventionally, a method of assembling a print sequence, such as logical seeking, has been adopted so as to prevent unnecessary head movement.
[0020]
As described above, in the pit-in type printer, head movement for ink replenishment not directly related to printing occurs.
[0021]
Therefore, depending on the timing of ink replenishment, the distance to the ink replenishment position may be long, and the time may be greatly lost.
[0022]
The present invention has been made in view of the above problems, and an object of the present invention is to determine a print scan in which a print head moving distance to an ink replenishment position is the shortest from a print sequence in a certain range, and determine the determined print scan. By refilling the ink, the time required for refilling the print head with ink is reduced, minimizing the disadvantage of taking time to refill ink, and the print head and main ink tank are separated. An object of the present invention is to provide an ink jet printer having the advantages of high speed, low cost, low noise, and mounting of a large capacity ink tank.
[0023]
[Means for Solving the Problems]
In order to achieve the above object, an image forming apparatus according to the present invention includes a print head that ejects ink, and an ink ejection type image forming apparatus that includes an ink tank that stores ink. An ink holding means for holding a certain amount of ink arranged with the print head, and an ink replenishing means for refilling the ink from the ink tank to the ink holding means, and the ink holding means only when the ink is replenished And the ink tank are connected by the ink replenishing means.Furthermore, the ink holding means and the ink tank can be connected only when the print head and the ink replenishing means have a specific positional relationship. A print sequence is determined from print data holding means for storing a fixed amount of data and the stored print data. A print sequence determining means and an ink replenishment timing control means for selecting an optimal ink replenishment timing from the determined print sequence are provided, and the print head and the ink replenishing means have a specific positional relationship to perform ink replenishment. In such a movement, the ink replenishment timing in the printing sequence is set so that the time required for the movement is minimized.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
One embodiment of the present invention will be described with reference to three figures.
[0025]
FIG. 1 is a block diagram of a pit-in type inkjet printer embodying the present invention.
[0026]
The printer is connected to a host PC, and print data generated by a printer driver on the host PC is received by print data receiving means of the printer.
[0027]
The received print data is held in the print data holding unit, and thereafter is read out by the print sequence determining unit.
[0028]
The print sequence determining means reads out the print data from the print data holding means and determines a head moving procedure, that is, a print sequence when printing the print data on the print medium.
[0029]
In accordance with the print sequence determined by the print sequence determining means, the print data is printed on the print medium by the printing means via the apparatus control means.
[0030]
On the other hand, the print sequence determined by the print sequence determination means is passed to the ink replenishment timing control means, and it is determined at which timing in the print sequence ink replenishment is performed to minimize the movement loss of the print head, An appropriate print scan is selected.
[0031]
The ink replenishment timing control means, when notified of the scan selected as the ink replenishment timing from the print sequence determination means or the apparatus control means, supplies the ink to the ink replenishment means via the apparatus control means. Give the order of.
[0032]
When receiving the ink replenishment command, the ink replenishment means appropriately uses the printing means and the device control means, moves the print head to the ink replenishment position, and replenishes the ink.
[0033]
The ink replenishment timing selected by the ink replenishment timing control means is not limited to once in one printing unit (for example, one page), and a plurality of scans may be selected.
[0034]
FIG. 2 is a structural view of a printing mechanism of a printer embodying the present invention as viewed from above. The print unit is provided with a print head and ink holding means.
[0035]
The printing unit is provided with an ink supply port, and the ink supply port is connected to the ink holding unit.
[0036]
When the printing unit moves to the ink supply position, the detachable ink supply pipe is inserted into the ink supply port.
[0037]
When the detachable ink replenishment pipe is not inserted, the ink replenishment port is closed with packing or the like in order to prevent evaporation of the ink from the ink holding means and contamination of impurities. The printing unit can move on the guide pipe in the length direction of the pipe, and prints on the printing medium while moving on the pipe.
[0038]
The print medium can move in a direction perpendicular to the direction in which the print unit moves, and in combination with the movement of the print unit, printing can be performed on the entire surface of the print medium.
[0039]
With the operation of moving the printing unit to the ink replenishing position or using a separate driving mechanism, after the detachable ink replenishing pipe is inserted, the ink in the ink tank is held in the printing unit by the ink replenishing pump. Replenish.
[0040]
FIG. 3 is a diagram showing a print sequence when printing on a print medium by the printer embodying the present invention and a timing of ink replenishment.
[0041]
The state of the movement of the print head (= print sequence) when printing the print data as shown in the figure on the print medium is shown. The procedure of moving the print head shown in this example is an example of the above-described logical seeking.
[0042]
Since the ink in the ink holding means is reduced by printing, the ink must be replenished during a certain range until the ink is empty. The range is shown as a supplementary study range. The ink replenishment timing control means obtains the print sequence shown in the figure before printing from the print sequence determination means, and determines a scan that minimizes head movement loss during the ink replenishment study range. And instructs ink replenishment in the scan.
[0043]
As described above, a print sequence in a certain range is determined in advance, the most efficient ink replenishment timing is determined from the information, and ink replenishment is performed at that timing, so that the print head movement time required for ink replenishment can be reduced. Can be minimized.
[0044]
【The invention's effect】
As described above, according to the present invention, by providing the ink replenishment timing control means, it is possible to analyze the print sequence and replenish the ink in the print scan in which the print head moving distance to the ink replenishment position is the shortest. It can minimize wasted time related to ink replenishment, so the printing speed is not reduced, and the advantages of the pit-in system include small, high-speed, low cost, low noise, and large-capacity ink tanks. An inkjet printer with advantages can be provided.
[Brief description of the drawings]
FIG. 1 is a block diagram of a pit-in type inkjet printer embodying the present invention.
FIG. 2 is a structural view of a printing mechanism of the printer as viewed from above.
FIG. 3 is a view showing a printing sequence when printing is performed on a printing medium by the printer, and a timing of ink replenishment.

Claims (1)

In an ink ejection type image forming apparatus including a print head that ejects ink and an ink tank that stores ink,
A configuration in which the print head and the ink tank are arranged separately,
An ink holding unit that can hold a certain amount of ink arranged with the print head,
Having ink replenishing means for replenishing ink from the ink tank to the ink holding means,
Only when refilling the ink, the ink holding means and the ink tank are connected by the ink replenishing means,
Furthermore, only when the print head and the ink replenishing means have a specific positional relationship, the ink holding means and the ink tank can be connected,
Print data holding means for storing a fixed amount of print data;
A print sequence determining means for determining a print sequence from the stored print data;
Providing ink replenishment timing control means for selecting the optimal ink replenishment timing from the determined printing sequence,
When the print head and the ink replenishing means are moved to have a specific positional relationship to perform ink replenishment, the ink replenishment timing in the print sequence is set so that the time required for the movement is minimized. Image forming apparatus.

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