JP3414112B2 - Inkjet printer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of ink jet printers having a function of initializing ink remaining amount measurement when an ink tank is attached.

[0002]

2. Description of the Related Art Conventionally, an ink jet printer ejects a dedicated ink in an ink tank from an ink jet nozzle formed in a print head to form dots on a printing paper and perform printing. In particular,
There is a type in which an ink jet nozzle is formed by a piezo element or the like, and by energizing the piezo element, the element is vibrated to eject ink.

By the way, generally, an ink jet nozzle using a piezo element is very delicate to heat, and if the high temperature continues, the element is destroyed. During normal operation when there is ink to be ejected, the temperature rise of the element is suppressed because the ink acts as a cooling liquid, but the printing operation (hereinafter, blank printing) is performed when the ink is exhausted. If this is done, the piezoelectric element, that is, the inkjet nozzle itself may be damaged due to element heat generation due to vibration. Since the piezo element is a very expensive member, it is required to eliminate the above-mentioned blank printing in order to prevent damage to the inkjet nozzle due to heat generation. To this end, it is necessary to accurately grasp the remaining amount of ink in the ink tank and stop printing before the ink runs out.

Even if the ink jet nozzles are not damaged, if the blank printing state occurs during printing on the printing paper, not only the printed matter printed up to now is wasted, but also the pages after that are reprinted. Will be required. In order to eliminate such wasteful printing and reprinting, it is conceivable to stop the printing before the ink runs out and restart the printing after the ink tank is replaced. Therefore, for this reason as well, it is required to accurately grasp the ink remaining amount in the ink tank and stop printing before the ink runs out.

In response to such a problem, the conventional ink jet printer is provided with an ink end detecting section for detecting a state where the ink remaining amount in the ink tank is low (hereinafter, "ink end state"). ing. Then, the "ink end state" is detected by the ink end detection unit.
When it detects that the ink tank has been detected, it is provided with a function of notifying it to the outside and prompting the replacement of the ink tank.

There are various methods for detecting the "ink end state" by the ink end detecting section, and the most commonly used method at present is a method of subtracting and counting the ink amount. This is to calculate the ejected ink amount by counting the amount of ink ejected from the inkjet nozzle, and to subtract the ejected ink amount from the total amount of ink filled in the ink tank to calculate the ink remaining amount. Is. Then, when the remaining amount of ink reaches the preset remaining amount of ink, status information indicating that it is in the “ink end state” is transmitted to the outside (for example, the display panel) from the ink end detection unit. ing.

As described above, in the conventional ink jet printer which calculates the ink remaining amount by counting the ink amount ejected from the ink jet nozzle, normally, the ink tank is newly attached at the timing of initializing the count value. It is common to set the time. That is, when the ink tank is mounted, the count value by the ink end detection unit is initialized to a preset value, and the amount of ejected ink is counted and the remaining amount of ink is measured each time printing is performed.

[0008]

However, in such a conventional ink jet printer, generally, the ink residual amount measurement value is initialized each time the ink tank is attached, and therefore, the following description will be made. There was a problem as described in.

That is, in the conventional ink jet printer, the counter value of the ink remaining amount is initialized based on the mounting operation of the ink tank regardless of the actual ink remaining amount in the ink tank. Therefore, for example, if the user temporarily removes the ink tank to check the remaining amount of ink, and then attaches the same ink tank again after checking the remaining amount, the count value is initialized and the correct remaining amount of ink remains. It becomes impossible to measure.

This is because the re-installed ink tank is not in an unused state like a new ink tank even if the ink is still in a sufficient state,
This is because the ink end detection unit that detects the "ink end state" based on the ink remaining amount in the unused state cannot detect the "ink end state".

In other words, if the ink tank that is in use is removed and then reattached, the "ink end state" cannot be detected even if there is no ink in the ink tank, and there is a high possibility that blank printing will be performed. . Therefore, not only the printing cannot be performed without the transmission of the “ink end state”, but also the expensive inkjet nozzle may be damaged as described above.

Further, as described above, even if the ink jet nozzle is not damaged, if the blank printing is performed during printing on the printing paper, the printed matter printed up to now is wasted and the printing is performed again. There is a problem that is required.

An object of the present invention is to solve the above problems and to provide an ink jet printer which can accurately detect the remaining amount of ink even when the ink tank is attached or detached.

[0014]

An ink jet printer of the present invention has a tank holder for mounting an ink tank filled with ink, and when mounting the ink tank on the tank holder, an ink supply port of the ink tank. In the ink jet printer that breaks the cap seal that closes the ink, inserts the suction nozzle into the ink supply port, and takes the ink in the ink tank into the apparatus main body, the amount of ink ejected during printing is counted, and the counted ink A remaining amount calculation unit that calculates the remaining amount of ink by subtracting the amount from the total amount of ink in the ink tank; a pressure detection unit that detects the pressure applied to the tip of the suction nozzle when the ink tank is mounted; Based on the pressure detected by the pressure detection unit, the amount of discharged ink is counted by the remaining amount calculation unit. It is configured with an initialization determination unit for determining whether or not to initialize the value, the.

Here, the suction nozzle includes a suction port member that is inserted into the ink supply port, a support member that slidably supports the suction port member, and a space between the suction port member and the support member. An elastic member having a predetermined urging force is provided, and is configured to be expandable and contractible depending on the magnitude relationship between the pressure applied to the suction port member and the urging force of the elastic member, and the pressure detecting unit is When the pressure applied to the suction port member reaches or exceeds a predetermined value, the switch has the pressing part provided on the suction port member side and the switch provided on the support member side. It is configured to turn on and output a control signal to the initialization determination unit to the effect that the count value is initialized.

The urging force of the elastic member is f1 which is the maximum force applied to the suction port member when the suction nozzle is inserted into the ink supply port before the cap seal is broken. The maximum force applied to the suction port member when the suction nozzle is inserted into the ink supply port after the breakage is f2, and is applied to the suction port member because the pressing portion turns on the switch. When the minimum force is f3, it is effective to set it so as to satisfy the formula shown by f1 ≧ f3> f2.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a functional block diagram of essential parts in the ink jet printer of this embodiment.

As shown in FIG. 1, an ink jet printer 1 according to this embodiment has an ink tank 2 for storing ink to be ejected and a tank holder 3 for holding the ink tank 2 by mounting the ink tank 2. And a remaining amount calculation unit 4, a pressure detection unit 5, and an initialization determination unit 6.

FIG. 2 is an exploded perspective view showing the essential structure of the tank holder of this embodiment, and FIG. 3 is a sectional view of the tank holder when the ink tank is mounted.

The ink tank 2 is a rectangular parallelepiped case for containing ink used for printing, and an ink supply port 2a for supplying ink is formed on the bottom surface of the case. In the unused ink tank 2, the ink supply port 2a is closed by a cap seal 2b made of metal foil. Therefore, when the ink tank 2 is mounted on the tank holder 3, the cap seal 2b is ruptured by applying a predetermined pressure from above with the cap seal 2b pressed against the suction nozzle 7 described later. The ink tank 2 is filled with urethane foam having a high hygroscopic property so that the ink in the ink tank 2 does not leak outside after the cap seal 2b is broken.

The tank holder 3 is a box-shaped container having ribs 3a formed on the inner wall surface thereof, and holds the ink tank 2 mounted by mounting the ink tank 2 firmly. An engagement portion 3b for positioning the ink supply port 2a when the ink tank 2 is attached is formed on the bottom surface of the tank holder 3, and the engagement portion 3b will be described later in the approximate center thereof. A hole 3c for forming the tip of the suction nozzle 7 is formed. Further, a print head (not shown) is formed integrally with the tank holder 3 and is configured to be movable in the main scanning direction along a guide rail (not shown), thereby functioning as a carriage. I also have.

The suction nozzle 7 has a hole 3 as shown in FIG.
A suction port member 7a which is inserted into the ink supply port 2a via c to suck the ink, a support member 7b which slidably supports the suction port member 7a, a suction port member 7a and a support member 7
a spring 7c which is an elastic member provided between b,
It is composed of a suction port member 7a, a support member 7b, and a cap 7d that houses a spring 7c. Inlet member 7
A protrusion 8a serving as a pressing portion is formed at a lower end position of a, and a tact switch 8b is provided at a position of the support member 7b facing the protrusion 8a.

Further, an ink introduction path is formed inside the suction port member 7a and the support member 7b which constitute the suction nozzle 7, and the ink sucked from the suction port member 7a is at the lower end position of the support member 7b. It is sent out to the print head through the ink tube 9 attached to the.

The remaining amount calculation unit 4 calculates the remaining amount of ink in the ink tank 2. Specifically, the remaining amount is discharged from the ink jet nozzle under conditions such as the rank of the ink jet nozzle and the general operating temperature. The amount of ink ejected from the inkjet nozzle is calculated by presetting the amount of ink to be ejected and counting the number of times of driving the inkjet nozzle based on the data to be printed. Then, the remaining ink amount is calculated by subtracting the calculated ejected ink amount from the total ink amount value in the ink tank 2.

The pressure detector 5 detects the pressure applied to the tip of the suction nozzle 7 when the ink tank 2 is mounted on the tank holder 3, and specifically, the suction port member 7a.
The suction port member 7a is pushed down by the pressure applied to
It is determined whether or not a force greater than the biasing force of the spring 7c is applied to the suction port member 7a depending on whether or not the protrusion 8a turns on the tact switch 8b. That is, the suction nozzle 7 also has a function as the pressure detection unit 5. When the tact switch 8b is turned on, the detection signal is output to the initialization determination unit 6.

The initialization determination unit 6 determines and determines whether or not to initialize the count value of the ejected ink amount in the remaining amount calculation unit 4 based on the detection signal output from the tact switch 8b. . Specifically, the detection signal output from the tact switch 8b is checked, and if the detection signal is on, the count value indicating the ejected ink amount in the remaining amount calculation unit 4 is initialized, while if the detection signal is off. For example, the count value in the remaining amount calculation unit 4 remains unchanged. That is, when the ink tank 2 is attached to the tank holder 3, the count value is initialized if a force of a certain value or more is applied to the tip of the suction nozzle 7, and the count value is initialized if a force of less than the certain value is applied. To cancel.

That is, in the present embodiment, the ink tank 2 in the unused state is generally closed by the cap seal 2b made of metal foil for the ink supply port 2a, and the ink tank 2 is newly installed. Whether the ink tank 2 is old or new is determined by utilizing the difference between the force applied to the suction nozzle 7 when the ink tank 2 is mounted and the force applied to the suction nozzle 7 when the ink tank 2 that has been once mounted is remounted. Specifically, when the suction nozzle 7 is inserted into the ink supply port 2a before the cap seal 2b is broken, the maximum force applied to the suction port member 7a is f1, and the suction nozzle 7 is broken after the cap seal 2b is broken. When the maximum force applied to the suction port member 7a when inserting the ink into the ink supply port 2a is f2, and the minimum force applied to the suction port member 7a because the tact switch 8b is turned on by the protrusion 8a is f3, The biasing force of the spring 7c is set so as to satisfy the expression of f1 ≧ f3> f2.

FIG. 4 is a summary of the forces required to mount a commercially available ink tank on the tank holder. It should be noted that FIG. 4 shows the forces applied at the time of mounting the five samples A to E in an unused state and mounting after use.

As shown in FIG. 4, each of the samples A to E of the ink tank 2 is 100 when mounted in an unused state.
A force of 0 gf or more is required, and 400 after use.
It can be seen that it can be installed if there is a force of gf or more. That is, considering the range of Samples A to E, the force applied to the suction port member 7a for turning on the tact switch 8b is 1
Considering the range of 000 gf to 400 gf and the operating margin, the biasing force of the spring 7c should be set to be about 700 gf.

The operation of the above embodiment will be described below with reference to FIG.
~ It demonstrates with reference to FIG.

FIG. 5 is a flow chart showing the process associated with the replacement of the ink tank, and FIG. 6 is a sectional view for explaining the change in the state of the suction nozzle. In the following description, S indicates a processing step.

First, during normal printer processing (S
In 1), it is checked whether or not a replacement request for the ink tank 2 has occurred, for example, when the remaining ink amount in the ink tank 2 is in the "ink end state" (S).
2). Then, as a result of the determination processing in S2, if there is no request for replacement of the ink tank 2, the printer processing in normal time is continuously executed again.

On the other hand, as a result of the judgment processing in S2,
If there is a request to replace the ink tank 2, the tank holder 3
Is driven to the cartridge replacement position (S3) and waits until the ink tank 2 is mounted (S4). Then, when the ink tank 2 is attached, the detection signal from the tact switch 8b is checked (S5).

Here, when the ink tank 2 is an unused item, the ink supply port 2a is closed by the cap seal 2b as described above. Therefore, when the ink tank 2 is mounted, the suction nozzle 7 is , The state shown in FIG. 6 (a) is changed to the state shown in FIG. 6 (d) through the state shown in FIG. 6 (b). As a result, the tact switch 8
b is turned on, and the initialization determination unit 6 recognizes that the ink tank 2 is an unused product.

Further, when the ink tank 2 whose cap seal 2b has been broken once is to be reattached, the suction nozzle 7 is set to the position shown in FIG.
From the state shown in FIG. 6A to the state shown in FIG.
The state changes to that shown in (d). That is, in this case, since the tact switch 8b is not turned on, the initialization determination unit 6 recognizes that the ink tank 2 is not an unused product.

FIG. 7 is a flow chart showing the remaining amount calculation process and the initialization judgment process. FIG. 7A shows a flowchart showing the remaining amount calculation process, and FIG. 7B shows the initialization judgment process. It is a flowchart.

In the remaining amount calculation process shown in FIG. 7A, first, when printing is performed by main scanning drive (S11), the amount of ejected ink is counted and added to the count variable I (S12). Since the count variable I is initialized (= “0”) by the initialization determination process described later,
The initial value is "0". Next, the total amount of the ejected ink amount is obtained based on the count variable I, and the remaining amount is calculated by subtracting this total value from the total ink amount value in the ink tank 2 (S13).

In the initialization determination process shown in FIG. 7B, first, it is checked whether or not the ink tank 2 is attached to the tank holder 3 (S21), and when it is attached, the tact switch 8b outputs the output. Check the detection signal (S
22). Then, if the detection signal is ON in the determination process of S22, the count variable I currently used in the remaining amount calculation process is initialized (= "0") (S2).
3).

On the other hand, if the detection signal is OFF in the determination process of S22, the count variable I currently used in the remaining amount calculation process is used as it is, and the initialization process is canceled. As a result, the count variable I is initialized only when the unused ink tank 2 is mounted.

Therefore, even if the user temporarily removes the ink tank 2 to check the remaining amount of ink and attaches the same ink tank 2 again after confirming the remaining amount, the count variable is changed in the re-attached ink tank 2. It is possible to accurately measure the remaining ink amount without initializing I.

As described above, in this embodiment, when the ink tank 2 is attached to the tank holder 3, it is easily judged whether or not the attached ink tank 2 is in the unused state. Only, the count variable I in the remaining amount calculation unit 4 is initialized. As a result, it is possible to accurately measure the remaining ink amount and protect the print head that is delicate against heat. Further, it is possible to save the labor of performing the printing again without causing a wasteful printed matter in the middle of printing.

Although the spring 7c is used as the elastic member in the above-described embodiment, it may be replaced with a member having a predetermined elastic coefficient such as rubber or leaf spring. Further, in the above-described embodiment, the function of the pressure detection unit 5 is realized by the protrusion 8a of the suction nozzle 7 and the tact switch 8a, but in this case, the suction port member 7a.
As a sensor for detecting the position of, for example, a non-contact type position sensor or the like may be used.

[0044]

As is apparent from the above description, according to the present invention, the count value in the remaining amount calculation section is initialized only when the ink tank is first mounted. Can accurately detect the remaining amount of ink.

[Brief description of drawings]

FIG. 1 is a functional block diagram of a main part of an inkjet printer according to an embodiment.

FIG. 2 is an exploded perspective view showing a main configuration of a tank holder according to this embodiment.

FIG. 3 is a cross-sectional view of the tank holder when the ink tank is attached.

FIG. 4 is a summary view showing a force required when a commercially available ink tank is attached to a tank holder.

FIG. 5 is a flowchart showing a process associated with replacement of an ink tank.

FIG. 6 is a sectional view for explaining a change in state of the suction nozzle.

FIG. 7 is a flowchart showing remaining amount calculation processing and initialization determination processing.

[Explanation of symbols]

1 inkjet printer 2 ink tank 2a Ink supply port 2b cap seal 3 tank holder 3a rib 3b Engagement part 3c hole 4 Remaining amount calculation part 5 Pressure detector 6 Initialization judgment section 7 Inhalation nozzle 7a Inlet member 7b Support member 7c Spring (elastic member) 7d cap 8a Projection (pressing part) 8b Tact switch (switch) 9 ink tubes

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-4-79644 (JP, A) JP-A-5-270001 (JP, A) JP-A-6-966 (JP, A) JP-A-7- 205419 (JP, A) JP-A-7-309018 (JP, A) JP-A-9-226143 (JP, A) JP-A-63-147649 (JP, A) JP-A-3-505999 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41J 2/175 B41J 2/125

Claims (3)

(57) [Claims] 1. A tank holder for mounting an ink tank filled with ink, wherein when the ink tank is mounted on the tank holder, a cap seal that closes an ink supply port of the ink tank is broken to supply the ink. In an inkjet printer that inserts a suction nozzle into the mouth and takes in the ink in the ink tank into the main body of the device, counts the amount of ink ejected during printing and subtracts the counted ink amount from the total amount of ink in the ink tank Based on the pressure detected by the pressure detection unit, the pressure detection unit that detects the pressure applied to the tip of the suction nozzle when the ink tank is mounted, An initialization determination unit that determines whether or not to initialize the count value of the ejected ink amount in the remaining amount calculation unit, An ink jet printer comprising: 2. The suction nozzle is provided between the suction port member inserted into the ink supply port, a support member slidably supporting the suction port member, and the suction port member and the support member. An elastic member having a predetermined biasing force,
And is configured to be expandable / contractible depending on the magnitude relationship between the pressure applied to the suction port member and the urging force of the elastic member, and the pressure detection unit includes a pressing unit provided on the suction port member side, A switch provided on the support member side,
When the pressure applied to the suction port member exceeds a predetermined value, the pressing unit turns on the switch, and outputs a control signal for initializing the count value to the initialization determination unit. The inkjet printer according to claim 1, wherein the inkjet printer is formed. 3. The maximum force applied to the suction port member when the suction nozzle is inserted into the ink supply port before the cap seal is broken is f1, and the maximum force applied to the suction port member is f1 after the cap seal is broken. When the maximum force applied to the suction port member when the suction nozzle is inserted into the ink supply port is f2, and the minimum force applied to the suction port member to turn on the switch by the pressing portion is f3. 3. The ink jet printer according to claim 2, wherein the urging force of the elastic member is set so as to satisfy the formula of f1 ≧ f3> f2.