JP2008183881A - Device for detecting ink residual amount - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily constitute a device for detecting the residual amount of ink capable of detecting the remaining ink amount and the presence and absence of an ink cartridge. <P>SOLUTION: The device for detecting the residual amount of ink is equipped with a pendulum 30 which includes a permanent magnet 32 (a weight member) positioned in an initial location A in its original state inside an ink tank 21, an electromagnetic solenoid 42 (a moving means) which moves the permanent magnet 32 from the initial location A to an operation location B, an MR sensor 41 (a weight member detecting means) capable of detecting the permanent magnet 32 positioned in the initial location A and a timer 44a (a timing means) which times the time from the point that the permanent magnet 32 starts moving from the operation location B toward the initial location A to the point to be detected by the MR sensor 41. An electronic control unit 44 causes a display part 12 to display the absence of an ink cartridge 20 when the permanent magnet 32 is not detected by the MR sensor 41 and also causes the display part 12 to display the residual ink amount calculated depending on the time timed by the timer 44a. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink remaining amount detecting device, and more particularly to an ink remaining amount detecting device having a function of detecting the presence or absence of an ink cartridge.

As this kind of ink remaining amount detection device, for example, as described in Patent Document 1 below, the ink level can be removed from the mounting portion of the ink jet recording apparatus, and the liquid level of the ink is changed as the stored ink is consumed. An ink cartridge having an ink tank that descends, a float member that has a first magnet and is housed in the ink tank and floats on the liquid surface of the ink by buoyancy, and a magnet of the float member provided at the bottom of the ink tank And a Hall element capable of detecting a magnetic flux that increases when the second magnet and the first magnet are attracted to each other are known. In the ink remaining amount detection device described in Patent Document 1, when the ink in the ink tank is almost empty, the first magnet and the second magnet are attracted to each other. Then, an increase in magnetic flux in this attracted state is detected by the Hall element, so that the user is informed that the ink cartridge has run out of ink.
JP 2003-63030 A

  However, in the above-described conventional ink remaining amount detection device, even if it is possible to detect the ink remaining amount in the ink tank, the ink remaining amount detection device attaches the ink cartridge to the mounting portion (the presence or absence of the ink cartridge). It is not configured to be detectable. For this reason, in addition to the device for detecting the remaining amount of ink in the ink tank, there is a problem that a device for detecting the presence or absence of the ink cartridge is required separately.

  An object of the present invention is to simply configure an ink remaining amount detecting device that can detect the remaining amount of ink in an ink tank and can also detect the presence or absence of an ink cartridge.

Means for Solving the Problems and Effects of the Invention

  In order to solve the above-described problem, an ink remaining amount detection device according to the present invention includes an ink tank that is detachable from a mounting portion of an ink jet recording apparatus and in which the liquid level of the ink drops as the stored ink is consumed. An ink cartridge having a weight member located at an initial position on the lower side of the ink tank by its own weight in an initial state, and a moving means for moving the weight member from the initial position to an operating position on the upper side of the ink tank; A weight member detecting means provided corresponding to the initial position and capable of detecting the weight member; and from the time when the weight member starts moving from the operating position to when the weight member detecting means detects the weight member. An ink cartridge for detecting that the ink cartridge is not attached to the attachment portion when the weight member is not detected by the time measurement means for measuring time and the weight member detection means; No-trridge detection means, and a remaining ink amount calculation means for calculating the remaining ink amount in the ink tank according to the time measured by the timing means on condition that the weight member is detected by the weight member detection means And.

  In the ink remaining amount detecting device according to the present invention, when the weight member is not detected by the weight member detecting means, it is detected that the ink cartridge is not attached to the attachment portion by the ink cartridge absence detecting means. In addition, on the condition that the weight member is detected by the weight member detecting means, the ink remaining amount in the ink tank is calculated according to the time measured by the time measuring means. For example, when the time measured by the time measuring unit is smaller than a predetermined lower limit time, it can be considered that the ink remaining amount in the ink tank is empty. As described above, it is possible to easily detect that the remaining amount of ink is empty by determining that the remaining amount of ink in the ink tank is empty by using the time counted by the timing unit. Thus, the weight member detecting means can be effectively used to detect the remaining amount of ink and to detect the presence or absence of the ink cartridge.

  In carrying out the present invention, the weight member is a permanent magnet that constitutes a pendulum that is rotatably provided to draw a circular locus against the fluid resistance of the ink in the ink tank, and the movement The means may be an electromagnetic solenoid that moves the permanent magnet from the initial position toward the operating position by a magnetic force.

  According to this, a moving means can be comprised simply by using an electromagnetic solenoid. In addition, since the ink in the ink tank is agitated by the movement of the weight member, it is possible to effectively suppress the coagulation of the ink in the ink tank and prevent the quality of the ink liquid from deteriorating.

  In carrying out the present invention, the weight member detecting means is a magnetic sensor provided near the initial position and capable of detecting the permanent magnet located at the initial position, and the time measuring means is connected to the electromagnetic solenoid. It is also possible to set the time from the time when the excitation is turned on to the time when it is turned off and to measure the time until the magnetic sensor detects the magnetic force of the permanent magnet.

  According to this, the weight member detection means is provided in the vicinity of the initial position. Therefore, when the ink cartridge is mounted on the mounting portion, the weight member positioned below the ink tank is detected by the weight member detecting means by its own weight in the initial state, and the ink cartridge is mounted on the mounting portion. If not, the weight member is not detected by the weight member detecting means. For this reason, it is possible to easily detect the mounting of the ink cartridge on the mounting portion.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the appearance of a multifunction machine 10 equipped with an ink remaining amount detection device according to an embodiment of the present invention. The multi-function device 10 selectively selects ink IK (refer to FIG. 4) (hereinafter simply referred to as ink) of ink cartridges 20 (refer to FIG. 2) provided for the plurality of types of colors mounted on the mounting portion 11. It has a function as an ink jet recording apparatus that records an image on a recording sheet by discharging.

  As shown in FIG. 2, the ink cartridge 20 includes an ink tank 21 that can be attached to and detached from the mounting portion 11 of the multifunction machine 10 and has a bottom wall 22 (see FIG. 3) formed in a substantially semicircular shape. ing. The ink tank 21 is communicated with a recording head (not shown) via a communication path (not shown) and an ink discharge port 23. The ink level in the ink tank 21 drops as the stored ink is consumed. A pendulum 30 is provided in the ink tank 21.

  The pendulum 30 has a permanent magnet 32 fixed to one end of a connecting rod 31 and is rotatably provided to draw a circular locus against ink fluid resistance (pressure resistance, viscous resistance, etc.). Yes. The other end of the connecting rod 31 is supported by a support shaft 33 provided on the side wall 24 of the ink tank 21. The connecting rod 31 is made of, for example, resin, and is formed to have a strength, a shape, or the like that does not cause bending when the permanent magnet 32 rotates around the support shaft 33. The permanent magnet 32 (weight member) is disposed so that, for example, the N pole is on the lower side and the S pole is on the upper side, and is positioned at the initial position A near the deepest portion of the ink tank 21 by its own weight in the initial state. is doing.

  An MR sensor (Magneto Resistive Sensor) 41 is provided at a portion of the mounting portion 11 corresponding to the initial position A of the permanent magnet 32. The MR sensor 41 (weight member detecting means) is, for example, a semiconductor magnetoresistive element, and has a function of increasing resistance by receiving a magnetic field perpendicular to the upper surface thereof.

  An electromagnetic solenoid 42 is provided at a portion of the mounting portion 11 corresponding to a predetermined position on the rotation trajectory of the permanent magnet 32. The electromagnetic solenoid 42 (moving means) is arranged in a direction in which the intersection angle between the central axis and the vertical line is 5 ° to 30 °, and generates magnetic force when the excitation circuit 43 is turned on. The magnetic force of the electromagnetic solenoid 42 is set to a size that allows the permanent magnet 32 to be drawn from the initial position A toward the operating position B in a full state where the ink tank 21 is filled with ink.

  The MR sensor 41 and the excitation circuit 43 are connected to the electronic control unit 44. The electronic control unit 44 is constituted by a microcomputer having CPU, ROM, RAM, EEPROM, ASIC, timer 44a and the like as main components. The electronic control unit 44 executes the ink cartridge installation detection and ink remaining amount detection program of FIG. 5 and controls the display drive unit 45 and the printer drive unit 46. Note that the ink cartridge installation detection and ink remaining amount detection program in FIG. 5 is executed by turning on the power of the multifunction machine 10 or turning on the detection operation switch 13.

  The display driving unit 45 displays a predetermined message on the display unit 12 in accordance with an instruction from the electronic control unit 44. Specifically, the display drive unit 45 causes the display unit 12 to display “CARTRIDGE NO INSERT” when it is determined that the ink cartridge 20 is not mounted in the mounting unit 11 (no ink cartridge). Further, the display drive unit 45 determines that the ink in the ink tank 21 is empty when the ink reaches a predetermined lower limit. In this case, the display drive unit 45 causes the display unit 12 to display “INK EMPTY”. On the other hand, when it is determined that the ink in the ink tank 21 is not empty, information indicating the remaining amount of ink in the ink tank 21, for example, a pattern or numerical value indicating the remaining ink amount is displayed. When it is determined that the ink in the ink tank 21 is empty, the printer driving unit 46 stops the control of the recording head so that the driving current does not flow to the recording head.

  Next, the operation of the present embodiment configured as described above will be described. The electronic control unit 44 starts to execute the ink cartridge attachment detection and ink remaining amount detection program of FIG. 5 by turning on the power of the multifunction machine 10 or turning on the detection operation switch 13.

  The execution of the ink cartridge mounting detection and ink remaining amount detection program is started in step S10, and in step S11, it is determined whether or not the magnetism of the permanent magnet 32 is detected by the MR sensor 41. First, a case where the ink cartridge 20 is not attached to the attachment unit 11 will be described.

  In this case, since the magnetism of the permanent magnet 32 is not detected by the MR sensor 41, “No” is determined in step S11, and “CARTRIDGE NO INSERT” is displayed on the display unit 12 in step S12. The drive unit 45 is controlled. After the process of step S12, the execution of the ink cartridge attachment detection and ink remaining amount detection program is terminated in step S24.

  Next, a case where the ink cartridge 20 is mounted on the mounting portion 11 and the ink tank 21 is sufficiently filled with ink as shown in FIG. 7A will be described. In this case, since the magnetism of the permanent magnet 32 is detected by the MR sensor 41, “Yes” is determined in Step S11, and the processes after Step S13 are executed.

  In step S13, the excitation circuit 43 of the electromagnetic solenoid 42 is turned on. In step S14, a timer count T is started. In step S15, it is determined whether or not the timer count T has reached a predetermined time T0 or more. The predetermined time T0 is a time required for the electromagnetic solenoid 42 to attract the permanent magnet 32, and is set to a size of about several hundred ms, for example. If the timer count T is equal to or greater than the predetermined time T0, “Yes” is determined in step S15. After the excitation circuit 43 of the electromagnetic solenoid 42 is turned off in step S16, the timer count T is once set in step S17. It is cleared and starts counting again.

  In step S18, a time Tc from when the excitation circuit 43 of the electromagnetic solenoid 42 is turned OFF until the magnetism of the permanent magnet 32 is detected by the MR sensor 41 is calculated. After the process of step S18, it is determined in step S19 whether or not the time Tc is equal to or less than the predetermined time Te. This predetermined time Te is the time (lower limit time) until the permanent magnet 32 reaches the initial position A from the operating position B by the free fall of the pendulum 30 in a state where the ink remaining amount in the ink tank 21 is a predetermined lower limit value (empty). ) Is set.

  Now, since the ink tank 21 is sufficiently filled with ink, the time Tc is longer than the predetermined time Te as shown in FIG. Therefore, it determines with "No" in step S19, and controls the display drive part 45 so that the ink remaining amount according to time Tc is displayed on the display part 12 in step S23. That is, the electronic control unit 44 calculates the ink remaining amount corresponding to the time Tc with reference to the ink remaining amount table provided in the ROM. As shown in FIG. 6, this ink remaining amount table stores a time Tc that increases approximately proportionally from time Te to time Tf as the ink remaining amount increases from empty to full Zf. Instead of using the ink remaining amount table, the remaining ink amount that changes according to the time Tc is defined in advance by a function, and the remaining ink amount is calculated using the function. Good.

  As is clear from FIG. 6, when the ink tank 21 is sufficiently filled with ink, the permanent magnet 32 freely falls against the large fluid resistance (pressure resistance, viscous resistance, etc.) of the ink. The time Tc from the operating position B to the initial position A is a time Tf (upper limit time). Accordingly, in this case, the display unit 12 displays the ink remaining amount in a full state with a pattern or a numerical value so that the operator can easily recognize the ink remaining amount. After the processing in step S23, the timer count T is cleared in step S22, and the execution of the ink cartridge attachment detection and ink remaining amount detection program is ended in step S24.

  Next, the case where the ink remaining amount in the ink tank 21 becomes near empty or less as shown in FIGS. 7B and 7C will be described. In this embodiment, in this case as well, as in the case where the ink remaining amount in the ink tank 21 is full, “No” is determined in Step S19, and the processing in Step S23 is executed. In this case, as shown in FIGS. 8B and 8C, the time Tc gradually becomes shorter as the remaining ink amount decreases. Then, based on the ink remaining amount table, the ink remaining amount corresponding to the time Tc is calculated, and the calculated ink remaining amount is displayed on the display unit 12 as a picture or a numerical value.

  Next, the case where the ink remaining amount in the ink tank 21 becomes almost empty as shown in FIG. 7D will be described. In this case, as shown in FIG. 8D, the time Tc is equal to the time Te. Therefore, “Yes” is determined in step S19, and the processing after step S20 is executed.

  In step S20, the display drive unit 45 is controlled so that “INK EMPTY” is displayed on the display unit 12. In step S21, the printer drive unit 46 is controlled to stop. After the processing in step S21, the timer count T is cleared in step S22, and the execution of the ink cartridge mounting detection and ink remaining amount detection program is terminated in step S24.

  As is clear from the above description of the operation, in this embodiment, when the magnetism of the permanent magnet 32 is not detected by the MR sensor 41, the ink cartridge 20 is not attached to the attachment portion 11 by the processing of steps S11 and S12. Information “CARTRIDGE NO INSERT” is displayed on the display unit 12. Further, on the condition that the magnetism of the permanent magnet 32 is detected by the MR sensor 41, the remaining amount of ink in the ink tank 21 is calculated according to the time Tc counted by the timer 44a by the process of step S23. A picture or numerical value indicating the remaining ink amount is displayed on the display unit 12. Accordingly, the MR sensor 41 can be effectively used to detect the remaining amount of ink in the ink tank 21 and to detect the presence or absence of the ink cartridge 20.

  In this embodiment, since the electromagnetic solenoid 42 is used as the moving means, the structure of the moving means is simplified. Further, since the ink in the ink tank 21 is agitated by the movement of the permanent magnet 32, the ink in the ink tank 21 can be effectively prevented from coagulating and the quality of the ink can be prevented from deteriorating.

  In this embodiment, when it is determined by the process of step S19 that the time Tc timed by the timer 44a is equal to or shorter than the predetermined lower limit time Te, it indicates that the ink remaining amount in the ink tank 21 is empty. The information “INK EMPTY” is set to be displayed on the display unit 12. Thus, since it is determined using the time Tc that the ink remaining amount in the ink tank 21 is empty, it is easy to detect that the ink remaining amount is empty.

  In the above embodiment, the state of FIG. 7D is determined to be “Yes” in step S19 of FIG. 5, but the state of FIG. 7C is determined to be “Yes” in step S19 of FIG. May be.

  In the above embodiment, the electromagnetic solenoid 42 is used as the moving means. Instead, for example, as schematically shown in FIG. 12, the permanent magnet 242 is moved from the position corresponding to the initial position A to the operating position B. It is also possible to provide a link 243 that rotates to the corresponding position. The link 243 is provided so as to be rotatable around a support shaft 244 provided coaxially and relatively rotatably with the support shaft 33 of the pendulum 30, for example. The permanent magnet 242 is provided so as to be movable in the axial direction of the link 243 with respect to the link 243. In this modified embodiment, the permanent magnet 242 is rotated from the position corresponding to the initial position A to the position corresponding to the operating position B by the link 243, and then the permanent magnet 242 is separated from the permanent magnet 32 and the permanent magnet 32. Starts timing from the time when the pendulum 30 starts free fall. Also by this, it is possible to obtain the same operation and effect as the above embodiment.

  In the above embodiment, the permanent magnet 32 constituting the pendulum 30 is used as the weight member. However, the present invention is not limited to this. For example, the ink tank can be moved vertically from the lower position toward the upper position by the moving means. A magnet is provided to calculate the time required for the permanent magnet to move from the upper position to the lower position due to free fall, and using this calculated time, the remaining amount of ink and the presence or absence of the ink cartridge are detected as described above. Also good.

FIG. 2 is a perspective view of a multifunction machine including an ink remaining amount detection device according to an embodiment of the invention. FIG. 2 is a perspective view of a mounting portion of the multifunction machine shown in FIG. 1. FIG. 3 is a schematic diagram of an ink remaining amount detection device. FIG. 4 is a schematic diagram in which an ink cartridge of the ink remaining amount detection apparatus illustrated in FIG. 3 is displayed mainly using an ink tank. 4 is a flowchart of an ink cartridge installation detection and ink remaining amount detection program executed by the electronic control unit of FIG. 3. 6 is a graph showing a change characteristic of an ink remaining amount with respect to a time stored in an ink remaining amount table provided in the electronic control unit. (A) is explanatory drawing of the ink remaining state full. (B), (c) is explanatory drawing of a state with little ink remaining amount. FIG. 6D is an explanatory diagram when the ink remaining amount is empty. (A)-(d) is explanatory drawing which shows the output waveform of MR sensor of the state of Fig.7 (a)-(d), respectively. The principal part schematic diagram of the ink remaining amount detection apparatus which concerns on deformation | transformation embodiment of this invention.

Explanation of symbols

10 MFP (inkjet recording device)
DESCRIPTION OF SYMBOLS 11 Mounting part 12 Display part 13 Detection operation switch IK Ink 20 Ink cartridge 21 Ink tank 30 Pendulum 31 Connecting rod 32 Permanent magnet (weight member)
33 Support shaft 41 MR sensor (weight member detection means)
42 Electromagnetic solenoid (moving means)
43 Excitation circuit 44 Electronic control unit 44a Timer 45 Display drive unit 46 Printer drive unit 242 Permanent magnet 243 Link 244 Support shaft

Claims (3)

An ink cartridge having an ink tank that is detachable from a mounting portion of the ink jet recording apparatus and in which the liquid level of the ink drops as the stored ink is consumed;
A weight member located at an initial position on the lower side of the ink tank by its own weight in an initial state;
Moving means for moving the weight member from the initial position to an operating position above the ink tank;
A weight member detecting means provided corresponding to the initial position and capable of detecting the weight member;
Time measuring means for measuring time until the weight member is detected by the weight member detecting means from the time when the weight member starts moving from the operating position;
When the weight member is not detected by the weight member detection means, the ink cartridge absence detection means detects that the ink cartridge is not attached to the attachment portion;
Ink remaining amount calculation means for calculating the remaining amount of ink in the ink tank according to the time measured by the timing means on condition that the weight member is detected by the weight member detecting means;
An ink remaining amount detecting device comprising:   The weight member is a permanent magnet that constitutes a pendulum that is rotatably provided so as to draw a circular locus against the fluid resistance of the ink in the ink tank, and the moving means includes the permanent magnet The ink remaining amount detection device according to claim 1, wherein the ink remaining amount detection device is an electromagnetic solenoid that is moved from an initial position toward the operation position by a magnetic force.   The weight member detecting means is a magnetic sensor provided in the vicinity of the initial position and capable of detecting the permanent magnet located at the initial position, and the time measuring means is provided after excitation of the electromagnetic solenoid is turned on. The ink remaining amount detection device according to claim 2, wherein the ink remaining amount detection device is set to start timing from the time when it is turned off and to measure the time until the magnetic force of the permanent magnet is detected by the magnetic sensor.

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