JP4479176B2 - Inkjet recording apparatus and ink cartridge - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ink jet recording apparatus and an ink cartridge, and more particularly to an ink jet recording apparatus and an ink cartridge capable of accurately detecting ink empty.
[0002]
[Prior art]
As disclosed in Japanese Patent Application Laid-Open No. 2002-234180 (Patent Document 1), an ink jet recording apparatus that detects the remaining amount of ink with two electrodes is known. In this ink jet recording apparatus, one electrode is a hollow extraction needle that extracts ink from the ink container in which ink is stored, and the other electrode is a hollow external air introduction needle that introduces outside air into the ink container. A pair of electrodes composed of an extraction needle and an outside air introduction needle are arranged substantially in parallel at the bottom of the ink container. When ink is extracted from the extraction needle, the pressure in the ink container is reduced, and external air corresponding to the pressure drop is introduced into the ink container from the outside air introduction needle.
[0003]
[Patent Document 1]
JP 2002-234180 A (FIG. 2 etc.)
[0004]
[Problems to be solved by the invention]
However, as described above, when the outside air is introduced from the outside air introduction needle, the outside air becomes bubbles because the outside air introduction needle is in the ink. This state is schematically shown in FIG. When the ink extraction from the extraction needle 51 proceeds and the ink liquid level falls below the upper end of the barrier member 64 surrounding the outside air introduction needle 52 as shown in FIG. 7B, the extraction needle 51 and the outside air introduction needle 52 The electric conduction through the ink between the barrier member 64 is cut off and ink empty is detected. After that, bubbles rising in the barrier member 64 overflow from the upper end opening of the barrier member 64, and the extraction needle 51. And the outside air introduction needle 52 are electrically connected to each other, and the “ink present” state is detected again.
[0005]
As described above, even though the ink is in an empty state, erroneous detection may occur, and external air is drawn into the print head, causing a print defect.
[0006]
SUMMARY An advantage of some aspects of the invention is that it provides an ink jet recording apparatus and an ink cartridge capable of accurately detecting ink empty.
[0010]
[Means for Solving the Problems]
  Claim1The ink jet recording apparatus according to the present invention includes a pair of electrodes that are in contact with the ink in the ink container and spaced from each other, a detection unit that detects electrical characteristics between the pair of electrodes, and the pair of electrodes. A barrier that rises from the bottom of the ink container between the electrodes; a conduction path that is formed through the predetermined height of the barrier between the pair of electrodes when the ink is greater than or equal to a predetermined amount; and an ink from the ink container An introduction path for introducing outside air through the ink into the ink container as the ink is discharged,Formed above a through hole that becomes a part of the conduction path formed at a predetermined height of the barrier;Holding means for holding bubbles generated as the outside air is supplied through the ink, leaving the conduction path.
[0011]
  This claim1According to the ink jet recording apparatus described above, the barrier rising from the bottom of the ink container is disposed between the pair of electrodes that are in contact with the ink in the ink container and spaced apart from each other, so that the amount of ink exceeds a predetermined amount. In this case, a conduction path is formed for electrical conduction between the electrodes through a predetermined height of the barrier. The electrical characteristic between the electrodes conducted through the conduction path is detected by the detection means. When ink is discharged from the ink container, outside air is introduced through the ink through the introduction path as the ink is discharged, and bubbles generated as the outside air is introduced are retained by the holding means while leaving the introduction path. Is done.
[0012]
  Claim2The ink jet recording apparatus according to claim1In the ink jet recording apparatus described above, one of the pair of electrodes is formed in a hollow shape having the introduction passage for supplying the outside air into the ink container.
[0013]
  Claim3The ink jet recording apparatus according to claim2In the inkjet recording apparatus described above, the barrier is formed in a cylindrical shape surrounding the one electrode.
[0016]
  Claim4The ink jet recording apparatus according to claim1In the inkjet recording apparatus described above, the holding unit is a holding wall provided between the introduction path and the barrier, and has an opening through which ink flows in a position lower than the conduction path of the holding wall. The pair of electrodes are positioned with the holding means and the barrier interposed therebetween.
[0017]
  Claim5The ink jet recording apparatus according to claim1From4In the ink jet recording apparatus according to any one of the above, the holding unit is configured by a hollow member that extends in the vertical direction surrounding the introduction path and has an upper end opened by an opening.
[0018]
  Claim6The ink jet recording apparatus according to claim5In the ink jet recording apparatus described above, a plurality of communication holes for communicating the inside and the outside of the hollow member are formed in the side surface of the hollow member.
[0019]
  Claim7The ink jet recording apparatus according to claim5Or6In the ink jet recording apparatus, the hollow member is formed in a bowl shape that becomes wider toward the upper end, and has an opening at the upper end.
[0020]
  Claim8The ink jet recording apparatus according to claim5From7In the ink jet recording apparatus according to any one of the above, a plurality of protrusions are formed inside the hollow member.
[0021]
  Claim9The ink jet recording apparatus according to claim3In the ink jet recording apparatus described above, a protrusion is formed inside the cylindrically formed barrier.
[0027]
  Claim10The ink cartridge described is for storing ink, and an electrode insertion portion that is inserted so that a pair of electrodes are in contact with the ink in the ink cartridge, and a pair of electrodes inserted by the electrode insertion portion. A barrier rising from the bottom of the ink cartridge, a conduction path formed through a predetermined height of the barrier between the pair of electrodes when the ink is a predetermined amount or more, and accompanying discharge of ink from the ink container And introducing means for introducing outside air through the ink into the ink container, and holding means for holding bubbles generated as the outside air is supplied through the ink, leaving the conduction path.
[0028]
  This claim10According to the described ink cartridge, the pair of electrodes are inserted by the electrode insertion portion so as to come into contact with the ink in the ink cartridge, and a barrier rising from the bottom of the ink container is disposed between the inserted electrodes. When is greater than or equal to a predetermined amount, a conduction path is formed that electrically conducts between the electrodes through a predetermined height of the barrier. When ink is discharged from the ink container, outside air is introduced through the ink through the introduction path as the ink is discharged, and bubbles generated as the outside air is introduced are retained by the holding means while leaving the introduction path. Is done.
[0029]
  Claim11The described ink cartridge stores ink, a pair of electrodes arranged to contact the ink in the ink cartridge, a barrier rising from the bottom of the ink cartridge between the pair of electrodes, and the ink When the air flow is greater than or equal to a predetermined amount, a conduction path formed through the predetermined height of the barrier between the pair of electrodes, and outside air is introduced into the ink container as the ink is discharged from the ink container. And a holding means for holding bubbles generated as the outside air is supplied through the ink, leaving the conduction path.
[0030]
  This claim11According to the described ink cartridge, the pair of electrodes are arranged so as to come into contact with the ink in the ink cartridge.ArrangementA barrier rising from the bottom of the ink container is disposed between the formed electrodes, and when the amount of ink is a predetermined amount or more, a conduction path is formed to electrically connect the electrodes through a predetermined height of the barrier. When ink is discharged from the ink container, outside air is introduced through the ink through the introduction path as the ink is discharged, and bubbles generated as the outside air is introduced are retained by the holding means while leaving the introduction path. Is done.
[0031]
  Claim12The ink cartridge according to claim10 or 11In the ink cartridge according to any one of the above, one of the pair of electrodes is formed in a hollow shape having the introduction path for supplying the outside air into the ink container.
[0032]
  Claim13The ink cartridge according to claim12In the ink cartridge described above, the barrier is formed in a cylindrical shape surrounding the one electrode.
[0035]
  Claim14The ink cartridge according to claim10 or 11In the ink cartridge, the holding unit is a holding wall provided between the introduction path and the barrier, and has an opening through which ink flows at a position lower than the conduction path of the holding wall. The pair of electrodes are positioned with the holding means and the barrier interposed therebetween.
[0036]
  Claim15The ink cartridge according to claim10From14In the ink cartridge according to any one of the above, the holding unit is configured by a hollow member that extends in the vertical direction surrounding the introduction path and has an upper end opened by an opening.
[0037]
  Claim16The ink cartridge according to claim15In the ink cartridge described above, a plurality of communication holes for communicating the inside and the outside of the hollow member are formed in the side surface of the hollow member.
[0038]
  Claim17The ink cartridge according to claim15Or16The hollow member is formed in a bowl shape that becomes wider toward the upper end, and has an opening at the upper end.
[0039]
  Claim18The ink cartridge according to claim15From17In the ink cartridge according to any one of the above, a plurality of protrusions are formed inside the hollow member.
[0040]
  Claim19The ink cartridge according to claim13In the ink cartridge described above, a protrusion is formed inside the cylindrically formed barrier.
[0041]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first preferred embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a diagram schematically showing an ink jet recording apparatus 1 of the present invention.
[0042]
The ink jet recording apparatus 1 mainly includes a plurality of ink cartridges 2 each filled with four color inks of cyan, magenta, yellow, and black, a mounting unit 3 that detachably mounts the ink cartridge 2, and an ink A buffer tank 5 that stores ink supplied from the cartridge 2 via the ink supply tube 17, a print head 4 that ejects ink stored in the buffer tank 5 toward the printing paper 6, and the buffer tank 5 and printing A carriage 7 that is mounted with the head 4 and reciprocates in a linear direction, a carriage shaft 18 that serves as a guide for the carriage 7 to reciprocate, a transport mechanism 9 that transports the printing paper 6, and a purge device 10 are provided. .
[0043]
The ink cartridge 2 has two insertion portions 91 and 92 for electrodes at the bottom, and includes plugs 61 and 62 that seal the inside of each insertion portion. One plug 61 is in contact with the ink 60 through the extraction port 63 at the bottom of the ink cartridge 2, and the other plug 62 extends upward from the periphery of the insertion portion 92 at the bottom of the ink cartridge 2, and the upper end is opened by the opening 66. The ink 60 is in contact with the cylindrical barrier member 64.
[0044]
The mounting unit 3 includes a hollow extraction needle 51 that extracts the ink 60 stored in the ink cartridge 2 and supplies the ink 60 to the print head 4, and the outside air as the ink 60 is extracted from the extraction needle 51. The hollow outside air introduction needle 52 for introducing the ink into the ink cartridge 2 is disposed so as to protrude substantially in parallel. The lower end of the outside air introduction needle 52 is in contact with the ink in the ink storage chamber 14 provided in the mounting portion 3, and the upper portion of the ink storage chamber 14 is in communication with the communication passage 13 that is a passage communicating with the outside air. Yes.
[0045]
When the ink cartridge 2 is attached to the attachment portion 3, the extraction needle 51 penetrates the stopper 61 and enters the stopper 60, and comes into contact with the ink 60. The outside air introduction needle 52 penetrates the stopper 62 and enters and contacts the ink 60. The plugs 61 and 62 are made of an elastic material such as butyl rubber, can pierce the extraction needle 51 and the outside air introduction needle 52, and have an elastic action of restoring the sealed state even after the extraction.
[0046]
When ink is extracted from the extraction needle 51 as the ink is ejected by the print head 4 in the mounting state of the ink cartridge 2 in the mounting portion 3, the pressure in the ink cartridge 2 decreases, and the outside air corresponding to the pressure drop is reduced. Is introduced from the space in the ink storage chamber 14 through the introduction path in the hollow outside air introduction needle 52. The upper end opening of the extraction needle 51 is opened at a position lower than the upper end opening 66 of the barrier member 64 and near the bottom of the ink cartridge 2, so that the ink outside the cylindrical barrier member 64 can be almost used up. . The ink in the cylindrical barrier member 64 remains after the outside air introduction needle 52 is immersed.
[0047]
The print head 4 is provided with a plurality of nozzles, and the ink stored in the buffer tank 5 is ejected from the nozzles. Further, during the printing operation, printing is performed on the printing paper 6 by ejecting ink while the carriage 7 reciprocates. Furthermore, at the time of the purge process, the ink moves to a purge process execution position set outside the print range, and discharges ink containing foreign matters toward a waste ink tank (not shown) provided at the purge execution position.
[0048]
The purge device 10 is a device that performs a purge process for sucking high viscosity ink or air that closes the nozzles of the print head 4 to restore a good ejection state, and the print head 4 is in a purge process execution position. In this case, a purge cap 11 that forms a sealed space with the ejection surface in contact with the ejection surface of the print head 4 and a suction pump (PG pump) 12 that sucks ink are mainly provided. The purge cap 11 is configured to be movable in a direction in which it is in contact with and separated from the ejection surface.
[0049]
FIG. 2 is a block diagram showing an outline of the electric circuit configuration of the ink jet printer 1. The control device for controlling the ink jet printer 1 includes a main body side control board 30 and a carriage board 31 mounted on the carriage 7. The main body side control board 30 includes a microcomputer (CPU) having a one-chip configuration. ) 32, a ROM 33 storing various control programs executed by the CPU 32 and fixed value data, a RAM 34 which is a memory for temporarily storing various data, an EEPROM 35, an image memory 37, A gate array (G / A) 36 is mounted.
[0050]
The CPU 32, which is an arithmetic device, executes various processes in accordance with a control program 33a stored in advance in the ROM 33. Further, a print timing signal and a reset signal are generated, and each signal is transferred to G / A 36 described later. The CPU 32 is provided with an operation panel 38 for a user to give a printing instruction, a CR motor drive circuit 39 for driving the CR motor 16 for operating the carriage 3a, and a transport mechanism 9 to transport the recording paper 6. As an LF motor driving circuit 41 for operating a transport motor (LF motor) 40, a PG pump driving circuit 47 for driving the PG pump 12, an extraction needle 51 as a first electrode for determining ink empty, and a second electrode A detection circuit 50 for detecting a resistance value with respect to the outside air introduction needle 52, a paper sensor 42 for detecting the leading end of the printing paper 6, an origin sensor 43 for detecting the origin position of the carriage 3a, and the like are connected. The operation of each connected device is controlled by the CPU 32.
[0051]
The ROM 33 includes a control program 33a and a determination table memory 33b. The control program 33a stores a program for executing a process (not shown) for determining the remaining amount of ink stored in the ink cartridge 2, and the determination table memory 33b stores the ink empty of the ink cartridge 2. Data for determination, that is, a condition for determining ink empty from a resistance value between an extraction needle 51 and an outside air introduction needle 52 detected by a detection circuit 50 described later is stored. This determination condition is stored in a table in which the detected resistance value and the remaining ink amount are associated with each other.
[0052]
The RAM 34 is a rewritable volatile memory, and includes a print prohibition flag 34a and an ink empty flag 34b. The print prohibition flag 34a is a flag for prohibiting printing when a measured value of a remaining amount counter 35a described later falls below a predetermined value. When the print prohibition flag 34a is turned on, the CPU 32 prohibits the printing operation. The increment flag 34b is a flag for indicating whether or not the remaining amount of ink in the ink cartridge 2 is ink empty. The ink empty flag 34b is turned on / off based on the determination process by the control program 33a.
[0053]
The EEPROM 35 is a rewritable nonvolatile memory, and includes a remaining amount counter 35a. The remaining amount counter 35a is a counter for measuring the remaining amount of ink in the ink cartridge. Subtraction is performed sequentially from the quantity value. The remaining amount counter 35a is composed of four counters which are updated separately for each ink cartridge 2. The remaining amount counter 35a is reset to the initial value when a new ink cartridge 2 is mounted.
[0054]
The G / A 36, based on the print timing signal transferred from the CPU 32 and the image data stored in the image memory 37, print data (drive signal) for printing the image data on print paper, Outputs a transfer clock that synchronizes with print data, a latch signal, a parameter signal for generating a basic print waveform signal, and a discharge timing signal that is output at a fixed period, and a head driver is mounted on each of these signals. Transfer to the carriage substrate 31.
[0055]
The G / A 36 stores image data transferred from an external device such as a computer via a Centro interface (I / F) 44 in the image memory 37. The G / A 36 generates a Centro data reception interrupt signal based on the Centro data transferred from the host computer or the like via the I / F 44, and transfers the signal to the CPU 32. Each signal communicated between the G / A 36 and the carriage substrate 31 is transferred via a harness cable that connects the two. The CPU 32, the ROM 33, the RAM 34, and the G / A 36 are connected via a bus line 45.
[0056]
The carriage substrate 31 is a substrate for driving the print head 4 by a mounted head driver (drive circuit). The print head 4 and the head driver are connected by a flexible wiring board in which a copper foil wiring pattern is formed on a polyimide film having a thickness of 50 to 150 μm. This head driver is controlled via the G / A 36 mounted on the main body side control board 30 and applies a driving pulse having a waveform suitable for the recording mode to each driving element. Thereby, a predetermined amount of ink is ejected.
[0057]
The detection circuit 50 is a circuit that applies a voltage to the extraction needle 51 and the outside air introduction needle 52 and detects a resistance value of ink between the extraction needle 51 and the outside air introduction needle 52. An output based on the detected resistance value is transferred to the CPU 32, and data in which the resistance value stored in the determination table memory 33b is associated with the remaining ink amount is read and compared.
[0058]
The determination of in- empty is based on the state in which the liquid level of the ink 60 is higher than that of the opening 66 and the electrode between the extraction needle 51 and the outside air introduction needle 52 is conducted through the conduction path A through the ink passing through the opening 66. The CPU 32 determines a sudden change in resistance value between the electrodes when the liquid level of the ink 60 becomes lower than the opening 66 and the conduction between the electrodes is cut off (see FIG. 3). This is determined by comparing with the data in the memory 33b. If the CPU 32 determines that the ink is empty, the ink empty flag 34b is turned on to display the ink empty on the operation panel or the like. Preferably, after that, the printing operation is continued using the ink 60 remaining in the ink cartridge 2, and the ink consumption amount is subtracted from the remaining amount value by the remaining amount counter 35a, so that the remaining ink amount falls below the predetermined amount. When turning, the printing prohibition flag 34a is turned on to stop the printing operation.
[0059]
FIG. 3 is an enlarged cross-sectional view showing the bottom of the ink cartridge 2 in an enlarged manner. FIG. 3 shows a state where the ink 60 is consumed and the ink is empty.
[0060]
An extinguishing member 65 that extinguishes bubbles generated in the ink in the cylindrical barrier member 64 is provided at the upper end of the cylindrical barrier member 64. The extinguishing member 65 rises integrally from the bottom of the ink cartridge 2 in the same manner as the cylindrical barrier member 64, and its tip 76 is substantially above the opening from a position above the upper end opening of the cylindrical barrier member 64. It hangs down toward the center. As will be described later, the distal end portion 76 is formed in a pointed shape toward the upper end opening of the cylindrical barrier member 64 in order to facilitate the destruction of bubbles.
[0061]
When the ink in the ink cartridge 2 is extracted from the extraction needle 51, the pressure in the ink cartridge 2 is reduced as described above, and the outside air corresponding to the pressure drop is introduced into the hollow outside air introduction needle 52. At this time, the outside air rises in the cylindrical barrier member 64 as bubbles when it enters the ink from the upper end of the introduction path in the outside air introduction needle 52. When the liquid level of the ink outside the cylindrical barrier member 64 falls below the upper end of the barrier member 64, the bubbles that rise on the liquid level in the cylindrical barrier member 64 hit the tip 76 and are destroyed. For this reason, unlike the prior art, bubbles do not overflow from the upper end opening of the cylindrical barrier member 64 to the liquid level that falls outside the upper end opening, and the electrical continuity between the extraction needle 51 and the outside air introduction needle 52 is interrupted. Continue to maintain. Therefore, ink empty can be detected accurately.
[0062]
Next, a second embodiment will be described with reference to FIG. FIG. 4 is a cross-sectional view showing a cross section of the ink cartridge 2 in a state where the ink cartridge 2 of the second embodiment is mounted on the ink jet head 4, and FIG. FIG. 4B is a state diagram showing a state in which the ink 60 becomes ink empty. In addition, about the part same as 1st Example, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
[0063]
As in the first embodiment, the ink cartridge 2 of the second embodiment is provided with an extraction needle 51 and an outside air introduction needle 52, and from the bottom of the ink cartridge 2 to the inside so as to surround the outside air introduction needle 52. A cylindrical barrier member 164 extending toward the front and having a tip opened by an opening 166 is disposed. A cylindrical holding member 167 extending from the bottom of the ink cartridge 2 to the inside and reaching a position higher than the barrier member 164 and having a tip opened by an opening 168 is disposed inside the barrier member 164 and between the outside air introduction needles 52. It is arranged.
[0064]
The inside of the holding member 167 and the inside of the barrier member 164 communicate with each other through a communication path 169 formed at a position lower than the tip of the outside air introduction needle 52 at the bottom of the ink cartridge 2, and the liquid level of the ink 60 is opened 166. In the case of being further upward, the conduction between the electrodes of the extraction needle 51 and the outside air introduction needle 52 is conducted in the conduction path A through the communication path 169 and the opening 166, the ink 60 is consumed, and the liquid level is the opening 166. When it is lower, the conduction between the electrodes is cut off and it is determined that the ink is empty.
[0065]
As shown in FIG. 4A, when the amount of ink 60 is large, the bubbles W generated from the outside air introduction needle 52 move upward while being guided to the inside of the holding member 167. On the other hand, as shown in FIG. 4B, when the ink 60 becomes ink empty, the bubbles W are held inside the holding member 167. The bubble W inside the holding member 167 is gradually pushed upward by the bubble W generated from the outside air introduction needle 52, but the bubble W disappears with time or contacts the inner surface of the holding member 167. It disappears with the pressure to do. Note that the height of the holding member 167 is formed such that a large amount of bubbles W can be prevented from flowing out of the openings 168 even when a large amount of bubbles W are generated by performing a printing operation continuously. ing.
[0066]
The ink cartridge 2 configured as described above can hold the bubble W generated from the outside air introduction needle 52 in the holding member 167 higher than the barrier member 164, and the liquid level of the ink 60 outside the barrier member 164 is opened. It is possible to prevent the bubbles W from being accumulated in the vicinity of the opening 166 in a state lower than 166. Therefore, even when the printing operation is continuously executed and a large amount of bubbles W are generated, the bubbles W can be reliably held by the holding member 167 and the conduction between the electrodes due to the bubbles W can be prevented. It can be detected accurately.
[0067]
Next, a third embodiment will be described with reference to FIG. FIG. 5 is a cross-sectional view showing a cross section of the ink cartridge 2 in a state where the ink cartridge 2 of the third embodiment is mounted on the ink jet head 4, and FIG. FIG. 5B is a state diagram showing a state in which the ink 60 becomes ink empty. In addition, about the part same as 1st Example, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
[0068]
Similar to the first embodiment, the ink cartridge 2 of the third embodiment is provided with an extraction needle 51 and an outside air introduction needle 52. A barrier member 264 that surrounds the outside air introduction needle 52 and a bubble W at the upper part thereof. A holding member 267 that holds the inside of the ink cartridge is integrally formed in a cylindrical shape, extends inward from the bottom of the ink cartridge 2, and has a leading end opened by an opening 268.
[0069]
The inside and the outside of the holding member 267 communicate with each other through a plurality of conduction paths 270 formed on the side wall thereof. In the third embodiment, the size of the conduction path 270 is a hole having a diameter of approximately “0.6 millimeters” so that the bubbles W do not flow outside. When the liquid level of the ink 60 outside the barrier member 264 is above the conduction path 270 formed at the lowest position, the conduction path A is connected between the electrodes of the extraction needle 51 and the outside air introduction needle 52 via the conduction path 270. When the ink 60 is consumed and the liquid level becomes lower than the conduction path 270 formed at the lowermost position, the conduction between the electrodes is cut off and it is determined that the ink is empty.
[0070]
As shown in FIG. 5A, when the amount of ink 60 is large, the bubbles W generated from the outside air introduction needle 52 move upward while being guided inside the barrier member 264 and the holding member 267. On the other hand, as shown in FIG. 5B, when the ink 60 becomes ink empty, the bubbles W are held inside the holding member 267 higher than the barrier member 264. The bubble W inside the holding member 267 is gradually pushed upward by the bubble W generated from the outside air introduction needle 52, but the bubble W disappears over time or comes into contact with the corner of the conduction path 270. Disappear. Note that the height of the holding member 267 is formed such that a large amount of bubbles W can be prevented from flowing out of the openings 268 even when a large amount of bubbles W are generated due to continuous printing operations. ing.
[0071]
The ink cartridge 2 configured as described above can hold the bubble W generated from the outside air introduction needle 52 in the holding member 267, and the liquid level of the ink 60 outside the barrier member 264 is from the lowermost conduction path 270. It is possible to prevent the bubbles W from accumulating inside and outside the barrier member 264 in a low state. Therefore, even when the printing operation is continuously performed and a large amount of bubbles W are generated, the bubbles W can be reliably held by the holding member 267 and the electrodes can be prevented from conducting by the bubbles W. It can be detected accurately.
[0072]
Next, a fourth embodiment will be described with reference to FIG. FIG. 6 is an enlarged cross-sectional view showing an enlarged cross section of the ink cartridge 2 in a state where the ink cartridge 2 of the fourth embodiment is mounted on the ink jet head 4, and shows a state in which the ink 60 becomes ink empty. . In addition, about the part same as 3rd Example, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
[0073]
In the ink cartridge 2 of the fourth embodiment, the upper end portion of the holding member 267 in the configuration of the third embodiment is formed in a bowl shape (mortar shape or funnel shape) that widens as the tip moves upward, and further opens at the upper end thereof. A portion 272 is formed in communication with the holding member 267.
[0074]
The inside and the outside of the holding member 267 communicate with each other through a conduction path 270 formed between the barrier member 264 and the holding member 267. As in the third embodiment, the conduction path 270 is configured by a hole having a diameter of approximately “0.6 millimeters”. When the liquid level of the ink 60 outside the barrier member 264 is above the conduction path 270, the electrodes of the extraction needle 51 and the outside air introduction needle 52 are conducted through the conduction path 270 (see FIG. 5). When the ink 60 is consumed and the liquid level becomes lower than the conduction path 270, the conduction between the electrodes is cut off and it is determined that the ink is empty.
[0075]
When the ink 60 is in a large amount, the bubbles W generated from the outside air introduction needle 52 move upward while being guided inside the barrier member 264 and the holding member 267. On the other hand, when the ink 60 becomes empty, the bubble W is held inside the holding member 267, and when the bubble W is generated, the bubble W is held in the opening 272. The bubbles W held in the holding member 267 and the upper bowl-shaped portion are gradually pushed upward by the bubbles W generated from the outside air introduction needle 52, but the bubbles W disappear with time. It disappears in contact with the inner surface of the holding member 267. Note that the height of the holding member 267 and the size of the bowl-shaped portion indicate that a large amount of bubbles W flows out from the opening 272 even when a large amount of bubbles W is generated when the printing operation is continuously performed. It is formed so that it can be prevented.
[0076]
The ink cartridge 2 configured as described above can hold the bubble W generated from the outside air introduction needle 52 by the holding member 267 and the bowl-shaped portion above the holding member 267, and the liquid level of the ink 60 outside the barrier member 264 is guided. It is possible to prevent the bubbles W from accumulating inside and outside the barrier member 264 in a state lower than the passage 270. Therefore, even when the printing operation is continuously executed and a large amount of bubbles W are generated, the bubbles W can be reliably held by the holding member 267 and the opening 272, and conduction between the electrodes due to the bubbles W can be prevented. Ink empty can be detected accurately.
[0077]
The present invention has been described above based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications and changes can be easily made without departing from the spirit of the present invention. Can be inferred.
[0078]
For example, in the first embodiment, only one extinguishing member 65 is provided, but a plurality of extinguishing members may be provided above the opening 66 of the barrier member 64. In this way, the bubbles W can be more reliably damaged and eliminated.
[0079]
In the first embodiment, the opening 66 may have an inner diameter smaller than the inner diameter of the barrier member 64, and the tip of the barrier member 64 may be narrowed. In this way, the bubble W can be more reliably guided to the position where the tip portion 67 of the extinguishing member 65 is disposed, and the bubble W can be more reliably damaged and disappear. Furthermore, in each Example, it is good also as providing a protrusion on the inner surface of a holding member and a barrier member. When the protrusion is provided, when the bubble W is guided upward, the bubble W comes into contact with the protrusion and breaks, so that the bubble W can be more reliably extinguished.
[0080]
In the second to fourth embodiments, the configurations of the other embodiments can be taken in or combined with each other. For example, a bowl-shaped portion can be incorporated in the second and third embodiments, or the number of conductive portions 270 can be increased or decreased.
[0081]
Further, in each embodiment, the barrier member and the holding member are formed in a cylindrical shape, but they can be formed by being connected to the inner side surface of the ink cartridge between the extraction needle and the outside air introduction needle.
[0082]
In each of the above-described embodiments, the extraction needle 51 and the outside air introduction needle 52 enter when the ink cartridge 2 is mounted. However, the ink cartridge 2 includes a pair of electrodes in the ink cartridge 2 in advance. It is good as a thing.
[0085]
【The invention's effect】
  Claim1According to the ink jet recording apparatus described above, the barrier rising from the bottom of the ink container is disposed between the pair of electrodes that are in contact with the ink in the ink container and spaced apart from each other, so that the amount of ink exceeds a predetermined amount. In this case, a conduction path is formed for electrical conduction between the electrodes through a predetermined height of the barrier. The electrical characteristic between the electrodes conducted through the conduction path is detected by the detection means. When ink is discharged from the inside of the ink container, outside air is introduced through the ink through the introduction path as it is discharged, and bubbles generated as the outside air is introduced are held by the holding means while leaving the introduction path. . Therefore, when ink is consumed and the liquid level of the ink becomes lower than a predetermined height of the barrier, it is possible to reliably prevent conduction between the electrodes that should be blocked by air bubbles generated by the introduction of outside air. There is an effect that can be. If the conduction path is configured so as to correspond to the ink empty when the ink level is lower than the predetermined height of the barrier, there is an effect that the ink empty can be accurately detected.
  In addition, since the holding means is formed above the through hole that is a part of the conduction path formed at a predetermined height of the barrier, the air bubble can be guided upward from the through hole and the air bubble is in the vicinity of the through hole. You can prevent accumulation. Therefore, there is an effect that it is possible to prevent conduction between the electrodes through the bubbles and to accurately detect ink empty.
[0086]
  Claim2According to the described inkjet recording apparatus, the claim1In addition to the effects of the ink jet recording apparatus described in 1), one of the pair of electrodes is formed in a hollow shape having an introduction path for supplying outside air into the ink container. It can be used as a member to be introduced, and there is an effect that the number of parts can be reduced and the manufacturing cost of the apparatus can be reduced.
[0087]
  Claim3According to the described inkjet recording apparatus, the claim2In addition to the effects of the inkjet recording apparatus described above, the barrier is formed in a cylindrical shape surrounding one electrode having an introduction path for supplying outside air into the ink container. The amount of ink remaining in the ink can be reduced.
[0090]
  Claim4According to the described inkjet recording apparatus, the claim1In addition to the effects of the ink jet recording apparatus described above, the holding means is a holding wall provided between the introduction path and the barrier, and is held at a position lower than the conduction path formed at a predetermined height of the barrier. The wall has an opening through which ink flows. For this reason, since the conduction path for conducting the electrodes can be separated from the space where the bubbles are held, it is possible to prevent conduction between the electrodes through the bubbles and to accurately detect the ink empty. There is an effect that can be done.
[0091]
  Claim5According to the described inkjet recording apparatus, the claim1From4In addition to the effect of the ink jet recording apparatus according to any one of the above, the holding means is composed of a hollow hollow member that surrounds the upper part of the introduction path and extends in the vertical direction and has an upper end opened by an opening. Can be reliably held in the holding means. Therefore, it is possible to prevent bubbles from being accumulated in the vicinity of the conduction path, to prevent conduction between the electrodes via the bubbles, and to detect ink empty accurately.
[0092]
  Claim6According to the described inkjet recording apparatus, the claim5In addition to the effects exhibited by the ink jet recording apparatus described above, a plurality of communication holes for communicating the inside and the outside of the hollow member are formed on the side surface of the hollow member. There is an effect that a plurality of conduction paths can be secured, and erroneous detection can be prevented before ink empty.
[0093]
  Claim7According to the described inkjet recording apparatus, the claim5Or6In addition to the effects of the ink jet recording apparatus described in 1., the hollow member is formed in a bowl shape that becomes wider toward the upper end, and has an opening at the upper end, so that it breaks when bubbles move above the holding member. The bubbles that have not been held are retained in the bowl-shaped portion. Therefore, even when a large amount of bubbles are generated, there is an effect that more bubbles can be held.
[0094]
  Claim8According to the described inkjet recording apparatus, the claim5From7In addition to the effects of the ink jet recording apparatus according to any one of the above, since a plurality of protrusions are formed inside the hollow member, the bubbles disappear more reliably when the bubbles move upward in the holding means. There is an effect that can be done.
[0095]
  Claim9According to the described inkjet recording apparatus, the claim3In addition to the effect of the ink jet recording apparatus described above, since the protrusion is formed inside the cylindrical barrier, there is an effect that bubbles generated from one electrode can be immediately extinguished.
[0099]
  Claim10According to the described ink cartridge, the pair of electrodes are inserted by the electrode insertion portion so as to come into contact with the ink in the ink cartridge, and a barrier rising from the bottom of the ink container is disposed between the inserted electrodes. Is a predetermined amount, a conduction path is formed to electrically conduct between the electrodes through a predetermined height of the barrier. When ink is discharged from the inside of the ink container, outside air is introduced through the ink through the introduction path as it is discharged, and bubbles generated as the outside air is introduced are held by the holding means while leaving the introduction path. . Therefore, when ink is consumed and the liquid level of the ink becomes lower than a predetermined height of the barrier, it is possible to reliably prevent conduction between the electrodes that should be blocked by air bubbles generated by the introduction of outside air. There is an effect that can be. If the conduction path is configured to correspond to the ink empty when the ink level is lower than the predetermined height of the barrier, the ink empty can be accurately detected.
  In addition, since the holding means is formed above the through hole that is a part of the conduction path formed at a predetermined height of the barrier, the air bubble can be guided upward from the through hole and the air bubble is in the vicinity of the through hole. You can prevent accumulation. Therefore, there is an effect that it is possible to prevent conduction between the electrodes through the bubbles and to accurately detect ink empty.
[0100]
  Claim11According to the described ink cartridge, the pair of electrodes are arranged so as to come into contact with the ink in the ink cartridge.ArrangementA barrier rising from the bottom of the ink container is disposed between the formed electrodes, and when the ink is in a predetermined amount, a conduction path is formed to electrically connect the electrodes through a predetermined height of the barrier. When ink is discharged from the inside of the ink container, outside air is introduced through the ink through the introduction path as it is discharged, and bubbles generated as the outside air is introduced are held by the holding means while leaving the introduction path. . Therefore, when ink is consumed and the liquid level of the ink becomes lower than a predetermined height of the barrier, it is possible to reliably prevent conduction between the electrodes that should be blocked by air bubbles generated by the introduction of outside air. There is an effect that can be. If the conduction path is configured so as to correspond to the ink empty when the ink level is lower than the predetermined height of the barrier, there is an effect that the ink empty can be accurately detected.
  In addition, since the holding means is formed above the through hole that is a part of the conduction path formed at a predetermined height of the barrier, the air bubble can be guided upward from the through hole and the air bubble is in the vicinity of the through hole. You can prevent accumulation. Therefore, there is an effect that it is possible to prevent conduction between the electrodes through the bubbles and to accurately detect ink empty.
[0101]
  Claim12According to the described ink cartridge, the claim10 or 11In addition to the effect of the ink cartridge described in 1., one of the pair of electrodes is formed in a hollow shape having an introduction path for supplying outside air into the ink container, so that one of the electrodes introduces outside air. This can be used as a member to reduce the number of parts and the manufacturing cost of the apparatus.
[0102]
  Claim13According to the described ink cartridge, the claim12In addition to the effect of the ink cartridge described above, the barrier is formed in a cylindrical shape surrounding one electrode having an introduction path for supplying outside air into the ink container. Residual ink can be reduced.
[0105]
  Claim14According to the described ink cartridge, the claim10Or11The holding means is a holding wall provided between the introduction path and the barrier, and is held at a position lower than the conduction path formed at a predetermined height of the barrier. The wall has an opening through which ink flows. For this reason, since the conduction path for conducting the electrodes can be separated from the space where the bubbles are held, it is possible to prevent conduction between the electrodes through the bubbles and to accurately detect the ink empty. There is an effect that can be done.
[0106]
  Claim15According to the described ink cartridge, the claim10From14In addition to the effect exhibited by any of the ink cartridges described above, the holding means is configured by a hollow hollow member that surrounds the upper part of the introduction path and extends in the vertical direction and has an upper end opened by an opening. It can be reliably held in the holding means. Therefore, it is possible to prevent bubbles from being accumulated in the vicinity of the conduction path, to prevent conduction between the electrodes via the bubbles, and to detect ink empty accurately.
[0107]
  Claim16According to the described ink cartridge, the claim15In addition to the effects exhibited by the ink cartridge described above, the side surface of the hollow member has a plurality of communication holes that communicate the inside and the outside of the hollow member. There is an effect that a plurality of paths can be secured and erroneous detection can be prevented before ink empty.
[0108]
  Claim17According to the described ink cartridge, the claim15Or16In addition to the effects exhibited by the ink cartridge described in 1., the hollow member is formed in a bowl shape that becomes wider toward the upper end and has an opening at the upper end, so that it is damaged when bubbles move above the holding member. The bubbles that did not exist are held in the bowl-shaped part. Therefore, even when a large amount of bubbles are generated, there is an effect that more bubbles can be held.
[0109]
  Claim18According to the described ink cartridge, the claim15From17In addition to the effect of the ink cartridge described in any of the above, since a plurality of protrusions are formed inside the hollow member, the bubbles disappear more reliably when the bubbles move upward in the holding means. There is an effect that can be.
[0110]
  Claim19According to the described ink cartridge, the claim13In addition to the effect produced by the ink cartridge described above, since the protrusion is formed inside the cylindrical barrier, there is an effect that bubbles generated from one electrode can be immediately extinguished.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing an ink jet recording apparatus 1 of the present invention.
FIG. 2 is a block diagram showing an outline of an electric circuit configuration of the ink jet printer.
FIG. 3 is an enlarged cross-sectional view showing an enlarged cross section of the bottom of the ink cartridge in a state where the ink cartridge is mounted on the inkjet head.
FIG. 4 is a cross-sectional view showing a cross section of an ink cartridge in a state where the ink cartridge of the second embodiment is mounted on an ink jet head, and FIG. FIG. 4B is a state diagram showing a state where the ink becomes ink empty.
FIG. 5 is a cross-sectional view showing a cross section of an ink cartridge in a state where the ink cartridge of the third embodiment is mounted on an ink jet head, and FIG. FIG. 5B is a state diagram showing a state where the ink becomes ink empty.
FIG. 6 is an enlarged cross-sectional view showing an enlarged cross section of the ink cartridge in a state where the ink cartridge of the fourth embodiment is mounted on the inkjet head.
7A and 7B are cross-sectional views for explaining problems in a conventional apparatus, in which FIG. 7A is a state diagram showing a state where a large amount of ink is present, and FIG. It is the state figure which showed the state which becomes an empty.
[Explanation of symbols]
1 Inkjet printer (inkjet recording device)
32 CPU
50 Detection circuit (detection means)
51 Extraction needle (one of a pair of electrodes)
52 Outside air introduction needle (one of a pair of electrodes) (part of conduction path)
64, 164 barrier member
65 Disappearing member
66 opening (part of conduction path)
167 Holding member (holding means) (hollow member)
169 Communication path (part of conduction path)
H.264 cylinder (part of holding means) (part of hollow member)
267 Holding part (part of holding means) (part of hollow member)
270 conduction path (part of conduction path)
272 opening

Claims (19)

A pair of electrodes that are in contact with the ink in the ink container and spaced from each other;
Detecting means for detecting electrical characteristics between the pair of electrodes;
A barrier rising from the bottom of the ink container between the pair of electrodes;
A conduction path formed through a predetermined height of the barrier between the pair of electrodes when the ink is a predetermined amount or more;
In an ink jet recording apparatus comprising an introduction path for introducing outside air through ink into the ink container as the ink is discharged from the ink container,
Formed above a through hole that is a part of the conduction path formed at a predetermined height of the barrier, and holds bubbles generated when the outside air is supplied through ink, leaving the conduction path. An ink jet recording apparatus comprising a holding means for performing the above operation. The pair of one electrode is an ink jet recording apparatus according to claim 1, characterized in that it is formed in a hollow shape having the introduction passage for supplying the outside air into the ink container therein. The inkjet recording apparatus according to claim 2 , wherein the barrier is formed in a cylindrical shape surrounding the one electrode. The holding means is a holding wall provided between the introduction path and the barrier, and has an opening through which ink flows at a position lower than the conduction path of the holding wall;
The inkjet recording apparatus according to claim 1 , wherein the pair of electrodes are positioned with the holding unit and the barrier interposed therebetween. It said retaining means extends vertically surrounds an upper portion of the introduction path, upper end according to any one of claims 1, characterized in that it is constituted by a hollow of the hollow member which is open by the opening 4 of the Inkjet recording device. 6. The ink jet recording apparatus according to claim 5 , wherein a plurality of communication holes for communicating the inside and the outside of the hollow member are formed in a side surface of the hollow member. The inkjet recording apparatus according to claim 5 , wherein the hollow member is formed in a bowl shape that becomes wider toward the upper end, and has an opening at the upper end. The inkjet recording apparatus according to claim 5, wherein a plurality of protrusions are formed inside the hollow member. The inkjet recording apparatus according to claim 3 , wherein a protrusion is formed inside the cylindrical barrier. In an ink cartridge for storing ink,
An electrode insertion portion that is inserted so that the pair of electrodes is in contact with the ink in the ink cartridge;
A barrier rising from the bottom of the ink cartridge between the pair of electrodes inserted by the electrode insertion portion;
A conduction path formed through a predetermined height of the barrier between the pair of electrodes when the ink is a predetermined amount or more;
An introduction path for introducing outside air through the ink into the ink container as the ink is discharged from the ink container;
Formed above a through hole that is a part of the conduction path formed at a predetermined height of the barrier, and holds bubbles generated when the outside air is supplied through ink, leaving the conduction path. An ink cartridge comprising: a holding unit that performs the above operation. In an ink cartridge for storing ink,
A pair of electrodes arranged to contact the ink in the ink cartridge;
A barrier rising from the bottom of the ink cartridge between the pair of electrodes;
A conduction path formed through a predetermined height of the barrier between the pair of electrodes when the ink is a predetermined amount or more;
An introduction path for introducing outside air through the ink into the ink container as the ink is discharged from the ink container;
Formed above a through hole that is a part of the conduction path formed at a predetermined height of the barrier, and holds bubbles generated when the outside air is supplied through ink, leaving the conduction path. An ink cartridge comprising: a holding unit that performs the above operation. 12. The ink cartridge according to claim 10 , wherein one of the pair of electrodes is formed in a hollow shape having the introduction path for supplying the outside air into the ink container. The ink cartridge according to claim 12 , wherein the barrier is formed in a cylindrical shape surrounding the one electrode. The holding means is a holding wall provided between the introduction path and the barrier, and has an opening through which ink flows at a position lower than the conduction path of the holding wall;
12. The ink cartridge according to claim 10 , wherein the pair of electrodes are positioned with the holding unit and the barrier interposed therebetween. It said retaining means extends vertically surrounds an upper portion of the introduction path, upper end according to any one of claims 10, characterized in that it is constituted by a hollow of the hollow member which is open by the opening 14 of the ink cartridge. The ink cartridge according to claim 15 , wherein a plurality of communication holes communicating the inside and the outside of the hollow member are formed in a side surface of the hollow member. The ink cartridge according to claim 15 or 16 , wherein the hollow member is formed in a bowl shape that becomes wider toward the upper end, and has an opening at the upper end. The ink cartridge according to claim 15, wherein a plurality of protrusions are formed inside the hollow member. The ink cartridge according to claim 13 , wherein a protrusion is formed inside the cylindrically formed barrier.

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