JP4470427B2 - Inkjet printer - Google Patents

Description

  The present invention relates to an ink jet printer, and more particularly to an ink jet printer configured to perform continuous operation by allowing a plurality of ink tanks to communicate with one recording head so that ink can be supplied.

  In an ink jet printer that performs continuous operation, a plurality of ink tanks are connected to a single recording head so that ink can be supplied, and usually ink is supplied from any one of the plurality of ink tanks to the recording head. Is switched to supply ink from other ink tanks when the ink tank becomes empty (Patent Document 1).

In such a conventional ink jet printer, every time an ink tank runs out of ink, the ink tank is sequentially switched to another ink tank, so it is always determined which of the plurality of ink tanks is empty. I don't mean. For this reason, all of the plurality of ink tanks are provided with detection means such as a weight detection sensor or an optical remaining amount detection sensor for detecting ink outage and display means such as a warning lamp for displaying ink outage. The user is informed of which of the plurality of ink tanks has run out of ink, and prompts ink replacement.
Japanese Patent No. 3131964

  However, in such a conventional ink jet printer, since it is necessary to provide expensive detection means such as a weight detection sensor and an optical remaining amount detection sensor for the number of ink tanks, there is a problem of increasing the cost of the ink jet printer. is there.

  In addition, since all of the plurality of ink tanks may run out of ink, in order to be able to replace all the ink tanks, it must be arranged in a place where the user can easily access for replacement work. For this reason, there is a problem that the restriction on the installation location of the ink tank is increased and the degree of freedom of the layout of the mechanism of the printer is lowered.

  Therefore, the present invention eliminates the need to provide detection means for detecting ink outage, display means for displaying ink outage, etc. in all of the plurality of ink tanks, and reduces restrictions on the installation location of the ink tank. It is an object of the present invention to provide a continuous operation type ink jet printer that can improve the degree of freedom of the layout of the mechanism of the printer.

  Other problems of the present invention will become apparent from the following description.

  The above problems are solved by the following inventions.

According to the first aspect of the present invention, a plurality of ink tanks communicate with one recording head so that ink can be supplied, and ink is supplied from any one of the plurality of ink tanks to the recording head. And an ink jet printer having an ink supply control means for switching to supply ink from another ink tank when the ink tank has run out of ink,
The plurality of ink tanks communicate with each other so that ink can be supplied from one ink tank at a specific position to another ink tank.
An ink tank presence sensor for detecting the presence or absence of the ink tank at the specific position;
The ink supply control means first supplies ink to the recording head from the ink tank at the specific position, and also causes the ink tank at the specific position to run out of ink, causing the ink from the other ink tank to the recording head. If the ink tank presence sensor detects the presence of an ink tank because the ink tank at the specific position has been replaced with a new ink tank after switching to supply ink, the newly replaced specific position by the ink in the ink tank can be introduced into the other ink tank, always ink tank of the specific position of the plurality of ink tanks, characterized in that that control so that ink shortage earlier Inkjet printer.

According to a second aspect of the present invention, there is provided an intermediate for temporarily storing ink supplied from one of the plurality of ink tanks to the recording head between the recording head and the plurality of ink tanks. A tank,
Detecting means for detecting the remaining amount of ink in the intermediate tank;
The ink supply control means starts the ink storage in the intermediate tank when the detection means detects that the remaining amount of ink is exhausted, and the ink supply control means 2. The ink jet printer according to claim 1 , wherein when it is detected that the remaining amount of ink in the intermediate tank does not recover, it is detected that the ink tank has run out of ink .

According to a third aspect of the present invention, the plurality of ink tanks are arranged in the vertical direction so that the ink tank at the specific position is located at the uppermost position, The ink tank communicates with the ink supply path through an on-off valve so that ink can be supplied.
The ink supply control means switches the ink tank at the specific position to supply ink from the other ink tank to the recording head, and then the ink tank at the specific position becomes a new ink tank. When the ink tank presence / absence sensor detects that an ink tank is present, the ink in the ink tank at the specific position is allowed to flow into the other ink tank by natural flow by opening the on-off valve. an ink jet printer according to claim 1, wherein the controller controls the.

The invention according to claim 4 has a pump that is driven when ink is supplied from any one of the plurality of ink tanks to the recording head,
The ink supply control means controls the ink in the ink tank at the specific position to flow into the other ink tank by natural flow by opening the on-off valve when the pump is stopped. The inkjet printer according to claim 3 .

According to a fifth aspect of the invention, at least one of the plurality of ink tanks other than the ink tank at the specific position is not replaceable. It is an inkjet printer of description.

  According to the present invention, the ink supply to the recording head is controlled so that the ink tank that is always arranged in the same place among the plurality of ink tanks runs out of ink first. It is only necessary to inform the user of the ink out of the ink tank controlled by this, and it is not necessary to provide a detecting means for detecting the ink out, a display means for displaying the ink out, etc. in all of the plurality of ink tanks. Thereby, the number of detection means and display means for the ink tank can be reduced.

  Also, since the ink tank that is controlled to run out of ink is always the ink tank at the same location, it is only necessary to place the ink tank in a location where the user can easily access the printer. Can be reduced, and the degree of freedom of the mechanism layout of the printer can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of an ink supply system of an inkjet printer, and shows a first embodiment of the present invention. FIG. 2 is a configuration block diagram for controlling the ink supply system of the ink jet printer of FIG.

  As shown in FIG. 1, the ink jet printer 100 includes a recording head 1, an intermediate tank 2, a first ink tank 3, and a second ink tank 4, and the first ink tank 3 and the second ink tank. 4 communicates with the recording head 1 through an ink supply path 5, and ink can be supplied by an ink supply pump 6 provided in the ink supply path 5.

  The recording head 1 ejects ink supplied from the first ink tank 3 or the second ink tank 4 via the ink supply path 5 toward a recording medium (not shown) at a predetermined timing, thereby forming an image. Record. The recording head 1 is provided for each ink color when recording a full-color image using a plurality of colors of ink such as YMCK, for example, and includes an intermediate tank 2, a first ink tank 3, and a second ink. A plurality of ink supply systems including the tank 4, the ink supply path 5, and the ink supply pump 6 are also provided for each ink color. Here, a case where only one recording head 1 is used is illustrated.

  The intermediate tank 2 temporarily stores the ink supplied from the first ink tank 3 or the second ink tank 4 via the ink supply path 5. The intermediate tank 2 is formed in a flexible bag shape, expands when ink is supplied to the inside, and conversely contracts when the ink inside is consumed.

  The intermediate tank 2 is provided with an intermediate tank sensor 2a. The intermediate tank sensor 2 a detects the remaining amount of ink in the intermediate tank 2 by detecting the degree of swelling of the intermediate tank 2. The intermediate tank sensor 2a is not particularly limited as long as the remaining amount of ink in the intermediate tank 2 can be detected. In the present embodiment, although not shown, a shielding plate is provided on a part of the surface of the intermediate tank 2. The optical sensor for detecting the presence / absence of the shielding plate is arranged, so that when the ink in the intermediate tank 2 is consumed and contracted, the shielding plate reduces the detection range of the optical sensor. By detecting the disconnection, it is possible to detect the decrease in the remaining amount of ink.

  The first ink tank 3 and the second ink tank 4 store ink for image recording. In the present embodiment, the first ink tank 3 is in the form of an ink cartridge in which ink is stored in the form of an ink pack in a casing, and is disposed in a predetermined place in the inkjet printer 100 so as to be replaceable. Yes.

  On the other hand, the second ink tank 4 does not necessarily need to be replaced like the first ink tank 3, and is disposed in the ink jet printer 100 so as not to be replaced in the present embodiment.

  The replaceable first ink tank 3 is loaded in a location that is easily accessible by the user in the inkjet printer 100, and the first ink tank 3 is loaded at the loading site of the first ink tank 3. An ink tank presence / absence sensor 3a for detecting the presence / absence is provided. The ink tank presence / absence sensor 3a is not particularly limited as long as the presence / absence of the first ink tank 3 can be detected. Thus, a contact-type sensor that detects that the first ink tank 3 is present and detects that the first ink tank 3 is absent when the first ink tank 3 is removed and contact is cut off is used. .

  Similarly, an ink out indication lamp 3b made up of an LED or the like for notifying the user of the ink out of the first ink tank 3 is provided at the loading site of the first ink tank 3.

  The ink in the first ink tank 3 and the second ink tank 4 is supplied to the intermediate tank 2 by the operation of the ink supply pump 6 through the ink supply path 5 and temporarily stored in the intermediate tank 2. Thereafter, the intermediate tank 2 is supplied to the recording head 1. The ink supply path 5 includes a first on-off valve 7 that controls ink supply from the first ink tank 3 and a second on-off valve 8 that controls ink supply from the second ink tank 4. Also, a third on-off valve 9 for controlling the ink supply to the intermediate tank 2 is provided downstream of the first on-off valve 7 and the second on-off valve 8 and upstream of the intermediate tank 2. Is provided. The first on-off valve 7, the second on-off valve 8, and the third on-off valve 9 are configured by electrically openable valves, for example, electromagnetic valves.

  The detection signals from the intermediate tank sensor 2a and the ink tank presence / absence sensor 3a are input to the controller 10 as shown in FIG. The control unit 10 controls the opening / closing of the first on-off valve 7, the second on-off valve 8, and the third on-off valve 9 based on the detection signals of the intermediate tank sensor 2a and the ink tank presence / absence sensor 3a, and supplies ink. By controlling the operation of the pump 6, ink supply control means is configured to control the ink to be supplied from the first ink tank 3 or the second ink tank 4 to the intermediate tank 2.

  Here, when the ink is supplied to the intermediate tank 2, the control unit 10 always firstly supplies the ink from the first ink tank 3 to the intermediate tank 2 out of the first ink tank 3 and the second ink tank 4. Ink supply operation is controlled so as to switch to supply ink from the second ink tank 4 when it is detected that the first ink tank 3 has run out of ink. It has been programmed.

  In addition, as will be described in detail later, when the controller 10 detects that the first ink tank 3 is out of ink, the controller 10 turns on the ink out display lamp 3b and informs the user that the first ink tank 3 is out of ink. , Control to urge exchange.

  Reference numeral 11 in FIG. 2 is a timer that starts when a valve opening command is output to the third on-off valve 9. After the third on-off valve 9 is opened, The time during which ink is stored is monitored. The timer 11 is set with a predetermined time-up time sufficient to be expected to be filled with ink after ink is supplied to the intermediate tank 2, and the third on-off valve 9 is opened. After the ink storage in the intermediate tank 2 is started, if the intermediate tank sensor 2a does not expand even after a predetermined time has elapsed and the optical sensor does not detect the shielding plate, the time-up is controlled by the control unit 10. , The control unit 10 can detect that no ink is supplied to the intermediate tank 2. At this time, when the first on-off valve 7 is opened, it can be detected that the first ink tank 3 is out of ink, and when the second on-off valve 8 is opened, It can be detected that the second ink tank 4 is out of ink.

  FIG. 3 is a time chart showing the operation timing at the time of ink supply operation in the ink jet printer 100, and the ink supply operation of the ink jet printer will be described using this time chart.

  After the power is turned on, when the control unit 10 confirms that the ink tank presence sensor 3a has an ink tank, the control unit 10 opens the first on-off valve 7 and the third on-off valve 9, and the ink supply pump 6 is turned on. In operation, ink is supplied from the first ink tank 3 to the intermediate tank 2 via the ink supply path 5. At the same time, the timer 11 starts to start and monitors the passage of a predetermined time (T0).

  When the ink is normally supplied from the first ink tank 3 to the intermediate tank 2, the intermediate tank 2 is filled with ink before the time-up time set in advance in the timer 11, and expands. The tank sensor 2a outputs a detection signal to the control unit 10 by detecting the shielding plate. Upon receiving the detection signal from the intermediate tank sensor 2a, the control unit 10 resets the timer 11, closes the third on-off valve 9, opens the second on-off valve 8, and supplies ink. The pump 6 is stopped (T1). Thereafter, image recording is performed by the recording head 1 using the ink stored in the intermediate tank 2.

  When the ink in the intermediate tank 2 is consumed as the image is recorded, the intermediate tank 2 contracts, and the shielding plate eventually goes out of the detection range of the optical sensor. Thereby, the intermediate tank sensor 2a outputs an OFF signal to the control unit 10 (T2). At this timing, the control unit 10 closes the second on-off valve 8 to open both the first on-off valve 7 and the third on-off valve 9 as in the previous time, and the ink supply pump 6 is turned on. In operation, ink is supplied from the first ink tank 3 to the intermediate tank 2 via the ink supply path 5. At the same time, the timer 11 starts to start and monitors the passage of a predetermined time.

  If the ink remaining in the first ink tank 3 runs out during the supply of ink and the ink runs out, the intermediate tank 2 is not filled with ink, so the intermediate tank sensor 2 a expands the intermediate tank 2. Cannot be detected, the time-up time set in advance in the timer 11 elapses, and the timer 11 reaches time-up and outputs that fact to the control unit 10 (T3).

  The control unit 10 closes the first on-off valve 7 and opens the second on-off valve 8 at the timing when the timer 11 expires, and sets the ink supply source to the intermediate tank 2 as the first source. While switching from the ink tank 3 to the second ink tank 4, the ink out indicator lamp 3b provided at the loading site of the first ink tank 3 is turned on, and the user is out of ink in the first ink tank 3. Inform you.

  In addition, the control unit 10 restarts the start of the timer 11 at the timing of starting the opening of the second on-off valve 8, and resumes the passage of the predetermined time.

  Here, when the ink is normally supplied from the second ink tank 4 to the intermediate tank 2, the intermediate tank 2 is filled with ink before the time-up time set in advance in the timer 11 and expands. The intermediate tank sensor 2a outputs a detection signal to the control unit 10 by detecting the shielding plate. Upon receiving the detection signal from the intermediate tank sensor 2a, the control unit 10 resets the timer 11, closes the third on-off valve 9, and stops the ink supply pump 6 (T4).

  When the user removes the first ink tank 3 after the ink out display lamp 3b is lit at the timing T3, the ink tank presence / absence sensor 3a detects that the first ink tank 3 is absent. When one ink tank 3 is replaced with a new one and loaded, the presence or absence of the first ink tank 3 is detected by the ink tank presence sensor 3a (T5).

  Thus, when the first ink tank 3 is replaced with a new one, the first on-off valve 7 is opened. Therefore, at the timing of T5, the third on-off valve 9 is closed, and the first on-off valve 7 and the second on-off valve 8 are both opened, so that the new first ink tank The ink is supplied from 3 to the second ink tank 4, and the second ink tank 4 is always full of ink.

  In the present embodiment, the first ink tank 3 and the second ink tank 4 are arranged in the vertical direction, and the first ink tank 3 is arranged above the second ink tank 4. A preferred embodiment is shown. For this reason, the ink supply from the first ink tank 3 into the second ink tank 4 can be performed by natural flow without requiring the power of a pump or the like, and the mechanism of the inkjet printer 100 is simplified. And cost reduction.

  When the ink in the intermediate tank 2 is consumed with the subsequent image recording, the intermediate tank 2 contracts, and the shielding plate is again out of the detection range of the optical sensor. Thereby, the intermediate tank sensor 2a outputs an OFF signal to the control unit 10 (T6). At this timing, the control unit 10 opens both the first on-off valve 7 and the third on-off valve 9, operates the ink supply pump 6, and supplies the ink supply path 5 from the first ink tank 3. Ink is supplied to the intermediate tank 2 via At the same time, the timer 11 starts to start and monitors the passage of a predetermined time.

  Thereafter, when the ink is normally supplied from the first ink tank 3 to the intermediate tank 2, the intermediate tank 2 is filled with ink before the time-up time set in advance in the timer 11, and expands. The tank sensor 2a outputs a detection signal to the control unit 10 by detecting the shielding plate. Upon receiving the detection signal from the intermediate tank sensor 2a, the control unit 10 resets the timer 11, closes the third on-off valve 9, opens the second on-off valve 8, and supplies ink. The pump 6 is stopped (T7).

  Thereafter, the same operation as described above is repeated.

  As described above, in the present invention, the first ink tank 3 is always controlled so that the first ink tank 3 out of the first ink tank 3 and the second ink tank 4 always runs out of ink first. Therefore, it is only necessary to notify the user that the first ink tank 3 is out of ink. Since the first ink tank 3 is always arranged at the same place in the ink jet printer 100, it is not necessary to provide ink outage detection means for the number of ink tanks, and an increase in the cost of the ink jet printer can be suppressed. In particular, according to the present invention, there is no need to continuously detect that the remaining amount of ink in the first ink tank 3 and the second ink tank 4 has decreased, and simply the first ink tank 3. Since it is only necessary to detect the fact that the ink has run out, there is no need for complicated and expensive detection means for continuously monitoring the remaining amount of ink as detection means, and the detection means can be greatly simplified.

  In addition, since at least the first ink tank 3 has only to be replaceable, it is possible to reduce restrictions on the installation location of the ink tank, and it is possible to improve the degree of freedom of the mechanism layout of the printer.

  If the second ink tank 4 also runs out of ink after the first ink tank 3 is switched out so that ink is supplied from the second ink tank 4, the second ink tank 4 This can be determined by the fact that the intermediate tank sensor 2a does not output a detection signal even after a predetermined time has elapsed after the on-off valve 8 is opened. In this way, when the second ink tank 4 is also out of ink, the image recording is stopped, and after the replacement of the first ink tank 3 is completed, the processing is executed in the same manner as when the power is turned on.

  In the above description, after the third on-off valve 9 is controlled to be closed, the first on-off valve 7 and the second on-off valve 8 are always controlled to be in the open state, and the intermediate tank 2 While the ink is not supplied to the ink, the ink is always supplied from the first ink tank 3 to the second ink tank 4, but the present invention is not necessarily limited to this. When the first ink tank 3 is replaced with a new one, the first on-off valve 7 and the second on-off valve 8 are controlled so as to be in the open state. Control may be performed so that ink is supplied to the tank 4. However, as described above, if the first on-off valve 7 and the second on-off valve 8 are always controlled to be opened after the third on-off valve 9 is controlled to close, The second ink tank 4 can always be in a state where the remaining amount of ink is larger than that of the first ink tank 3, and when the first ink tank 3 is replaced with a new one, the first ink tank 3 is replaced with the first ink tank 3. The time loss for supplying ink from 3 to the second ink tank 4 can be prevented, which is particularly preferable in the present invention.

  Furthermore, the above description shows a mode in which both the first ink tank 3 and the second ink tank 4 are arranged below the intermediate tank 2, and for this reason, the first ink tank 3 or the second ink is shown. Ink supply from the tank 4 to the intermediate tank 2 is performed by operating the ink supply pump 6, but as in the second embodiment of the present invention shown in FIG. Both of the second ink tanks 4 may be arranged higher than the intermediate tank 2. In FIG. 4, the same reference numerals as those in FIG.

  In this case, since the ink supply from the first ink tank 3 or the second ink tank 4 to the intermediate tank 2 can be performed by natural flow, it is not necessary to provide the ink supply pump 6. Further simplification of the mechanism and cost reduction can be achieved.

  In the above description, the ink tank is composed of two ink tanks, ie, the first ink tank 3 and the second ink tank 4. However, in the present invention, the ink tank is the third ink tank as necessary. Three or more ink tanks may be provided, such as a fourth ink tank. Also in this case, the ink supply operation is controlled as described above, so that the ink is always consumed first from the first ink tank 3, so that the first ink tank 3 is first out of ink. It is controlled to become. In this case, at least one of the ink tanks other than the first ink tank 3 may not be replaceable.

1 is a schematic configuration diagram of an ink supply system of an ink jet printer according to a first embodiment. FIG. 1 is a block diagram of a configuration for controlling an ink supply system of the ink jet printer of FIG. Time chart showing operation timing during ink supply operation Schematic configuration diagram of an ink supply system of an inkjet printer according to a second embodiment

Explanation of symbols

1: Recording head 2: Intermediate tank 2a: Intermediate tank sensor 3: First ink tank 3a: Ink tank presence sensor 3b: Ink out indicator lamp 4: Second ink tank 5: Ink supply path 6: Ink supply pump 7 : 1st on-off valve 8: 2nd on-off valve 9: 3rd on-off valve 10: Control part 11: Timer 100: Inkjet printer

Claims (5)

A plurality of ink tanks communicate with one recording head so that ink can be supplied, ink is supplied from one of the plurality of ink tanks to the recording head, and the ink tank is out of ink. An ink jet printer having ink supply control means for switching to supply ink from another ink tank when
The plurality of ink tanks communicate with each other so that ink can be supplied from one ink tank at a specific position to another ink tank.
An ink tank presence sensor for detecting the presence or absence of the ink tank at the specific position;
The ink supply control means first supplies ink from the ink tank at the specific position to the recording head, and also causes the ink tank at the specific position to run out of ink, causing the ink head from the other ink tank to the recording head. If the ink tank presence sensor detects the presence of an ink tank because the ink tank at the specific position has been replaced with a new ink tank after switching to supply ink, the newly replaced specific position by the ink in the ink tank can be introduced into the other ink tank, always ink tank of the specific position of the plurality of ink tanks, characterized in that that control so that ink shortage earlier Inkjet printer. One intermediate tank that temporarily stores ink supplied from any of the plurality of ink tanks to the recording head between the recording head and the plurality of ink tanks;
Detecting means for detecting the remaining amount of ink in the intermediate tank;
The ink supply control means starts the ink storage in the intermediate tank when the detection means detects that the remaining amount of ink is exhausted, and the ink supply control means 2. The ink jet printer according to claim 1 , wherein when it is detected that the remaining amount of ink in the intermediate tank is not recovered, it is detected that the ink tank has run out of ink. The plurality of ink tanks are arranged in the vertical direction so that the ink tank at the specific position is located at the uppermost position, and the ink tank at the specific position and the other ink tanks lower than the ink tank are connected via an on-off valve. The ink supply path communicates so that ink can be supplied.
The ink supply control unit switches the ink tank at the specific position to a new ink tank after switching to supply ink from the other ink tank to the recording head when ink has run out. When the ink tank presence / absence sensor detects that an ink tank is present, the ink in the ink tank at the specific position is allowed to flow into the other ink tank by natural flow by opening the on-off valve. The inkjet printer according to claim 1 , wherein the inkjet printer is controlled as follows . A pump that is driven when ink is supplied from one of the plurality of ink tanks to the recording head;
The ink supply control means controls the ink in the ink tank at the specific position to flow into the other ink tank by natural flow by opening the on-off valve when the pump is stopped. The inkjet printer according to claim 3 . 5. The ink jet printer according to claim 1 , wherein at least one of the plurality of ink tanks other than the ink tank at the specific position is not replaceable.

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