JP4517789B2 - Filtration apparatus and inkjet recording apparatus having the same - Google Patents

Description

  The present invention relates to a filtering device and an ink jet recording apparatus having the same, and more particularly to a filtering device optimal for filtering ink and an ink jet recording apparatus having the same.

  2. Description of the Related Art Inkjet recording apparatuses that perform recording by ejecting ink droplets from an ejection surface of an inkjet recording head toward a recording medium are widely used. In such an ink jet recording apparatus, a filter having a filter is provided in an ink supply line to prevent clogging of an ejection port (nozzle) due to a foreign substance contained in the ink (see, for example, Patent Document 1). In recent years, it has been proposed to collect and reuse ink ejected from ejection ports (see, for example, Patent Document 2). In this case, it is indispensable to remove foreign matter.

  Thus, the filter part which comprises a filtration apparatus is an important component in an ink supply system.

  However, when used over a long period of time, foreign matters accumulate on the filter and cause clogging. For this reason, there is a problem that the flow path resistance increases, ink is not normally supplied to the ink jet recording head, and ink ejection failure occurs.

In order to prevent such ink ejection failure, replace the filter and filtration device regularly with a margin in a relatively short period of time, or install detection means (such as a flow meter) to detect the ink flow rate. Proposals have been made such as notification of the replacement time of filters and filtration devices (for example, see Patent Documents 3 and 4). However, adverse effects such as the need to frequently replace the filter and the filtration device and the high cost due to the installation of the detection means are assumed.
JP-A-9-141890 JP 2001-315359 A JP 2004-25727 A JP-A-11-320913

  In view of the above-described facts, an object of the present invention is to provide a low-cost and highly reliable filtration device and an ink jet recording apparatus having the same.

  The invention according to claim 1 is a filtration device that removes foreign matter in the liquid to be filtered by passing the filter part through the liquid to be filtered, the main channel provided with the filter part, and the main channel And a bypass flow path provided in parallel with the clogging detection filter section, and a detection enabling means for enabling detection of the liquid to be filtered flowing through the clogging detection filter section, The clogging detection filter section has a liquid-repellent surface and an opening diameter smaller than that of the filter section.

  The filter part and the clogging detection filter part may be any parts as long as they do not allow foreign matters having a diameter larger than the set diameter to pass therethrough, and may be constituted by, for example, a mesh-like net.

  In a state where the filter section provided in the main flow path is not clogged, the filtered liquid pressure is allowed to flow within a predetermined pressure range so that the filtered liquid does not flow into the bypass flow path but only in the main flow path. The liquid to be filtered flows.

  When the filter part is clogged, the liquid pressure to be filtered on the upstream side of the filter part and the clogging detection filter part rises, and the differential pressure with the downstream side increases. When the meniscus formed in the clogging detection filter portion is broken, the liquid to be filtered flows through the bypass flow path, and the detection enabling means detects this. Therefore, the operator can change the filtration device at an appropriate time.

  Thereby, a low-cost and highly reliable filtration device can be realized. Further, since the surface of the clogging detection filter portion is made liquid repellent, bubbles easily pass through. Therefore, it is suitable for removing bubbles.

  The invention according to claim 2 is characterized in that a contact angle of the liquid to be filtered is 90 ° or more on the surface of the clogging detection filter portion.

  Thereby, it is easy to increase the differential pressure between the filtered liquid pressure necessary for flowing the filter part and the filtered liquid pressure necessary for flowing the clogging detection filter part.

  The invention according to claim 3 is characterized in that the filter portion and the clogging detection filter portion are integrally formed, and can be integrally attached to and detached from the apparatus.

  Thereby, replacement | exchange with a filter part and the filter part for clogging detection can be performed efficiently in a short time.

  The invention according to claim 4 is characterized in that a transparent outer flow path wall that forms the bypass flow path downstream of the clogging detection filter portion is provided as the detection enabling means.

  Thereby, it can detect by visual observation etc. with a very simple structure.

  The invention described in claim 5 is characterized in that, as the detection enabling means, an electrode that is energized when a liquid to be filtered flows is disposed in the bypass flow channel downstream of the clogging detection filter unit. To do.

  Thereby, automatic detection can be performed with a simple configuration.

  According to a sixth aspect of the present invention, an ink jet recording head that ejects ink droplets and an ink supply line that supplies ink to the ink jet recording head are provided, and the filtering device according to the first aspect includes the ink supply line. It is provided in.

  Thereby, a low-cost and highly reliable ink jet recording apparatus can be realized.

  A seventh aspect of the present invention includes a liquid receiver that stores ink from the ink jet recording head, and a suction unit that sucks out ink from a discharge surface of the ink jet recording head via the liquid receiver. A reusable ink line is provided as a line for flowing part or all of the ink sucked out by the sucking means as ink to be reused, and the filtration device according to claim 1 is provided in the reusable ink line. It is characterized by being.

  The ink to be reused contains a large amount of foreign matter. Therefore, according to the seventh aspect of the invention, an ink jet recording apparatus that can efficiently filter the ink to be reused and further reduce the cost is realized.

  Since the present invention has the above-described configuration, it is possible to realize a low-cost and highly reliable filtration apparatus and an inkjet recording apparatus having the same.

  Hereinafter, embodiments will be described and embodiments of the present invention will be described. In the second and subsequent embodiments, the same components as those already described are denoted by the same reference numerals and description thereof is omitted.

[First Embodiment]
First, the first embodiment will be described.

(overall structure)
FIG. 1 shows an ink jet recording apparatus 12 according to the first embodiment. A paper feed tray 16 is provided in the lower part of the casing 14 of the ink jet recording apparatus 12, and the sheets P stacked in the paper feed tray 16 can be taken out one by one by a pickup roll 18. The taken paper P is transported by a plurality of transport roller pairs 20 constituting a predetermined transport path 22. Hereinafter, the term “transport direction” simply refers to the transport direction of the paper P that is a recording medium.

  Above the paper feed tray 16, an endless transport belt 28 stretched around a drive roll 24 and a driven roll 26 is disposed. A recording head array 30 is disposed above the conveyor belt 28 and faces the flat portion 28F of the conveyor belt 28. This opposed area is an ejection area SE where ink droplets are ejected from the recording head array 30. The sheet P transported along the transport path 22 is held by the transport belt 28 and reaches the discharge area SE, and ink droplets corresponding to image information are attached from the recording head array 30 in a state of facing the recording head array 30. The

  Then, by rotating the paper P while being held by the transport belt 28, the paper P can be passed through the discharge region SE a plurality of times, and so-called multipass image recording can be performed. Therefore, the surface of the conveyance belt 28 is a circulation path of the paper P in the present invention.

For example, the transport belt 28 is made of a semiconductive polyimide material (surface resistance value 10 ¹⁰ to 10 ¹³ Ω / □, volume resistance value 10 ⁹ to 10 ¹² Ω · cm), thickness 75 μm, width 380 mm, circumference What was shape | molded in length 1000mm can be used. Moreover, as the drive roll 24 and the driven roll 26, as an example, a φ50 mm SUS roll can be used.

  Further, without providing the conveyor belt 28, for example, a recording medium (paper P) may be sucked and held on the outer periphery of a conveyance roller formed in a cylindrical shape or a columnar shape and rotated. However, when the conveyor belt 28 is used as in the present embodiment, the flat portion 28F is formed, so that the recording head array 30 can be arranged corresponding to the flat portion 28F, which is preferable.

  In this embodiment, the recording head array 30 has a long shape in which the effective recording area is equal to or larger than the width of the paper P (the length in the direction orthogonal to the transport direction), and is yellow (Y) and magenta (M). , Cyan (C), and Black (K), four inkjet recording head units 32 (hereinafter simply referred to as head units 32) corresponding to the four colors are arranged along the transport direction to record full-color images. It is possible. The method of ejecting ink droplets in each head unit 32 is not particularly limited, and a known method such as a so-called thermal method or piezoelectric method can be applied.

  The ink jet recording head 33 constituting each head unit 32 is controlled by a head controller 60. For example, the head controller 60 determines the ejection timing of the ink droplets and the ink ejection port (nozzle) to be used according to the image information, and sends a drive signal to the inkjet recording head 33.

  The recording head array 30 may be stationary in a direction orthogonal to the transport direction. However, if the recording head array 30 is configured to move as necessary, an image with higher resolution can be obtained by multi-pass image recording. Or failure of the ink jet recording head 33 is not reflected in the recording result.

  In the head unit 32, reservoir tanks 64 corresponding to four colors of yellow (Y), magenta (M), cyan (C), and black (K) are arranged.

  Four maintenance units 34 corresponding to the respective head units 32 are arranged in the vicinity of the recording head array 30 (in this embodiment, both sides in the transport direction). When performing maintenance on the head unit 32, as shown in FIG. 2, the recording head array 30 moves upward, and the maintenance unit 34 moves into the gap formed between the conveyance belt 28 and enters. . Then, a predetermined maintenance operation (vacuum, dummy jet, wiping, capping, etc.) is performed in a state of facing the nozzle surface 33N (see FIG. 3) which is a discharge surface.

  In the present embodiment, the four maintenance units 34 are divided into two sets of two, and the recording head array 30 is arranged on the upstream side in the transport direction and the downstream side in the transport direction of the recording head array 30 during image recording. I am doing so.

  As shown in detail in FIG. 3, a charging roll 36 to which a power source 38 is connected is disposed on the upstream side in the transport direction of the recording head array 30. The charging roll 36 is driven while sandwiching the conveyance belt 28 and the paper P with the driven roll 26, and moves between a pressing position for pressing the paper P against the conveyance belt 28 and a separation position separated from the conveyance belt 28. It is possible. At the pressing position, a predetermined potential difference is generated between the grounded driven roll 26 and the sheet P can be charged and electrostatically attracted to the transport belt 28.

As the charging roll 36, for example, a roll having a diameter of 14 mm can be used in which conductive rubber is coated on the surface of silicone rubber and the volume resistance value is adjusted to about 10 ⁶ to 10 ⁷ Ω · cm.

  As the power source 38, a DC power source is shown in FIG. 3, but an AC power source may be used as long as the paper P can be charged to a predetermined potential.

  A registration roll (not shown) is provided further on the upstream side in the transport direction than the charging roll 36, and the paper P is aligned before reaching between the transport belt 28 and the charging roll 36.

  A peeling plate 40 (see FIGS. 1 and 2) is disposed on the downstream side in the transport direction of the recording head array 30, and the paper P can be peeled from the transport belt 28. As the peeling plate 40, for example, an aluminum plate having a thickness of 0.5 mm, a width of 330 mm, and a length of 100 mm can be used.

  The peeled paper P is transported by a plurality of rotatable discharge roller pairs 42 constituting a discharge path 44 on the downstream side in the transport direction of the peeling plate 40, and is discharged to a paper discharge tray 46 provided at the upper part of the housing 14. Discharged.

  Below the peeling plate 40, a cleaning roll 48 is disposed so that the conveyance belt 28 can be sandwiched between the drive roll 24 and the surface of the conveyance belt 28 is cleaned.

  A reversing path 52 including a plurality of reversing roller pairs 50 is provided as a reversing unit between the paper feed tray 16 and the conveying belt 28, and the sheet P on which an image is recorded on one side is reversed and conveyed. By holding the belt 28, image recording on both sides of the paper P can be easily performed.

  Between the conveyance belt 28 and the paper discharge tray 46, an ink tank 54 for storing each of the four color inks is provided. The ink in the ink tank 54 is supplied to each head unit 32 via the reservoir tank 64 by an ink supply line 62 (see FIG. 5). As the ink, various known inks such as water-based ink, oil-based ink, and solvent-based ink can be used.

  As shown in FIG. 4, the entire inkjet recording apparatus 12 is controlled by a controller 56, and operations including image recording, discharging, and maintenance are performed from taking out the paper P. Various data relating to the recorded image is sent from the image controller 58 to the controller 56. For example, as will be described later, the applied voltage and the like in the first charging mode and the second charging mode are controlled by the controller 56 in accordance with the data of the recorded image. The inkjet recording head 33 is controlled by a head controller 60, and a signal is transmitted from the controller 56 to the head controller 60. The controller 56, the head controller 60, and the charging roll 36 are supplied with power from a power source 38.

  In the ink jet recording apparatus 12 of the present embodiment configured as described above, the paper P taken out from the paper feed tray 16 is transported to the transport belt 28 as described above. Then, it is pressed against the conveyor belt 28 by the charging roll 36 and is held by being attracted (contacted) to the conveyor belt 28 by the voltage applied from the charging roll 36. In this state, while the paper P passes through the ejection area SE by circulation of the transport belt, ink droplets are ejected from the recording head array 30 and an image is recorded on the paper P. When recording an image in only one pass, the paper P is peeled from the transport belt 28 by the peeling plate 40, transported by the discharge roller pair 42, and discharged to the paper discharge tray 46. On the other hand, when performing image recording by multi-pass, after the paper P is circulated until it reaches the required number of times and passed through the ejection region SE, the paper P is peeled off from the transport belt 28 by the peeling plate 40, The paper is conveyed by the discharge roller pair 42 and discharged to the paper discharge tray 46.

(Ink flow line)
As shown in FIG. 5, the ink jet recording apparatus 12 is used for an ink supply line 62 for supplying ink from the ink tank 54 to the head unit 32, and for maintenance (when the ink jet recording head 33 is restored). An ink outflow line 63 whose flow direction can be switched is provided for each color.

  In the following, one color (for example, yellow) will be described in which ink is supplied from the ink tank 54 to the head unit 32 through the ink supply line 62 and ink is sucked from the ink outflow line 63 during the recovery operation of the ink jet recording head 33. To do. Since the other colors are the same, the description thereof is omitted.

  In the ink supply line 62, an unused ink filtering device 66 is provided between the ink tank 54 and the reservoir tank 64.

  In the ink jet recording apparatus 12, a reservoir tank filling pump 68 that is provided on the upstream side of the ink flow of the unused ink filtration device 66 and applies an ink delivery force to the ink supply line 62, and a reservoir tank filling pump 68. And a filling motor 70 for driving the motor. The filling motor 70 is controlled by the controller 56.

  Further, in order to monitor the amount of ink in the reservoir tank 64, a sensor 72 for detecting the presence or absence of ink at the low position L and the high position H in the reservoir tank 64 is provided. Data measured by the sensor 72 is transmitted to the controller 56.

  The head unit 32 includes a reservoir tank 64 provided for each color and a plurality of ink jet recording heads 33 provided below the respective reservoir tanks 64. Further, the reservoir tank 64 and the inkjet recording head 33 are connected by piping so that the ink flowing out from the reservoir tank 64 can reach the inkjet recording head 33.

  The lower surface side of the inkjet recording head 33 is a nozzle surface 33N, and 1024 nozzles are arranged.

  As shown in FIG. 5, the maintenance unit 64 is connected to the cap 88 that receives the ink from the nozzle surface 33N by being pressed against the nozzle surface 33N during the recovery operation of the ink jet recording head 33, and the outlet of the cap 88. And an ink outflow pipe 92 having a three-way valve 94 connected to the end thereof. The three-way valve 94 can switch the outflow direction, and the switching of the outflow direction is controlled by the controller 56.

  Further, a waste ink line 95 is provided which is connected to the three-way valve 94 and flows ink for waste liquid treatment. A waste ink tank 96 is provided at the downstream end of the waste ink line 95.

  Further, a reusable ink line 97 is provided which is connected to the three-way valve 94 and allows ink to be reused to flow. The reusable ink line 97 is provided with a recovery filtration device 99 that is detachable so as to be replaceable, and the downstream end of the reusable ink line 97 is connected to the reservoir tank 64.

  Further, the ink jet recording apparatus 12 includes a recovery operation pump 98 that sucks out ink from the cap 88 to the ink outflow pipe 92, and a recovery operation motor 100 that drives the recovery operation pump 98. The recovery operation motor 100 is controlled by the controller 56 similarly to the filling motor 70.

  When the recovery operation is started, the controller 56 switches the three-way valve 94 to flow to the waste ink line 95. Then, the cap 88 is pressed against the nozzle surface 33N of the inkjet recording head 33 so as to be in a mounted state (ON state). Further, the recovery operation pump 98 is driven to suck ink from the nozzle surface 33N of the ink jet recording head 33.

  After flowing the ink at the initial stage of suction to the waste ink line 95, the controller 56 switches the outflow direction of the three-way valve 94 to the reuse ink line 97. As a result, the reused ink passes through the recovery filter device 99 and is stored in the reservoir tank 64.

(Unused ink filtration device and recovery filtration device)
Hereinafter, the recovery filtering device 99 will be described in detail. The unused ink filter device 66 has the same basic configuration as the recovery filter device 99, and thus detailed description thereof is omitted.

  As shown in FIG. 6, the recovery filtration device 99 includes a main channel 104 through which ink flows and a bypass channel 106 formed in parallel with the main channel 104 outside the main channel 104. Has been. The main channel 104 is provided with a main filter part 108 through which ink passes, and the bypass channel 106 is provided with a clogging detection filter part 110. Further, the outer wall 107 of the bypass channel 106 that forms the downstream side of the clogging detection filter unit 110 is made of a transparent member, and can be detected visually when ink flows into the bypass channel 106. ing.

  In the present embodiment, the main filter portion 108 and the clogging detection filter portion 110 are integrally formed, and are detachable from the recovery filter device 99. Accordingly, it is possible to efficiently replace the filter in a short time and reuse the recovery filter 99.

  The clogging detection filter unit 110 has an opening diameter smaller than that of the main filter unit 108, that is, has a finer eye. Further, the surface of the clogging detection filter unit 110 is made liquid repellent, and the ink contact angle is 90 ° or more.

  Here, as shown in FIG. 7, when the contact angle θ with the used liquid (ink in this embodiment) is 90 ° or less (that is, when the adhesion force of the used liquid is larger than the cohesive force), the inflow side pressure Even if the differential pressure ΔP between P1 and the outflow side pressure P2 is a minute value, the meniscus S moves downward on the paper surface due to the surface tension T and the differential pressure ΔP, and the ink flows. For this reason, in this embodiment, as shown in FIG. 8, the surface layer material of the detection filter unit 110 is made water-repellent so that the contact angle θ with the working liquid is 90 ° or more (that is, the use Make the adhesive force of the liquid smaller than the cohesive force).

  As a result, the meniscus S is pulled upward by the surface tension T, and the meniscus S is maintained or moved by the relationship between the differential pressure ΔP and the surface tension T.

  Here, when the opening diameter of the clogging detection filter unit 110 is D, the differential pressure ΔP when the meniscus is pulled downward in the drawing and the used liquid flows out of the bypass channel 106 is generally expressed by the following equation.

ΔP = −4T cos θ / D
Therefore, the differential pressure ΔP to be detected can be set to a desired value by selecting the contact angle θ with the liquid to be used and the opening diameter D of the clogging detection filter unit 110.

  The recovery filtration device 99 is set so that the ink pressure passing through the clogging detection filter unit 110 is higher by ΔP than the ink pressure required to pass through the main filter unit 108 using such a principle. Has been. This ΔP is normally set small. In a state where the main filter unit 108 is not clogged, the ink flows only in the main flow path 104 as shown in FIG. 9 due to the liquid repellency of the surface of the clogging detection filter unit 110 and the surface tension of the ink. The bypass channel 106 does not flow.

  Then, when the main filter unit 108 is clogged, the ink pressure on the upstream side of the recovery filtering device 99 increases, the differential pressure with the downstream side increases, and the meniscus of the clogging detection filter unit 110 is broken. As shown in FIG. 10, the ink also flows through the bypass channel 106.

  When ink flows through the bypass channel 106, the operator can detect this at a glance and recognize that it is time to replace the recovery filter 99. Therefore, it can be avoided that the replacement time of the recovery filtering device 99 is too late, causing ink ejection failure, and the replacement time is too early and the cost is increased. Further, the configuration of the recovery filtering device 99 is simple.

  In addition, the differential pressure ΔP can be set to a set pressure in accordance with the performance required for the recovery filtration device 99.

  Further, since the recovery filtration device 99 and the unused ink filtration device 66 are detachable, the inkjet recording device 12 can be used continuously by replacing it with an unused recovery filtration device 99 or an unused ink filtration device 66. can do.

  Further, the main filter unit 108 and the clogging detection filter unit 110 are integrally formed, and can be attached to and detached from the recovery filter device 99, so that the filter can be efficiently replaced and recovered in a short time. The filter device 99 can be reused. The same applies to the unused ink filtration device 66.

  As shown in FIG. 11, instead of the outer wall 107, an outer wall 117 formed with a protruding portion 116 protruding in a V-shaped cross section is provided in the bypass channel 106, and a measurement laser is provided from the outer side of the protruding portion 116. It may be configured to detect that the ink has flowed into the bypass channel 106 by irradiating the light B and detecting the reflected light. In this configuration, when there is no ink inside the convex portion 116, that is, when no ink flows through the bypass flow path 106, the laser light B passes through the slope of the convex portion 116, and no reflected light is detected (FIG. 11). (See dashed line). When ink is present inside the convex portion 116, that is, when ink is flowing in the bypass flow path 106, the reflected light is detected because the laser beam B is reflected by the slope of the convex portion 116 (solid line in FIG. 11). reference). The convex portion 116 may be a conical convex portion.

  Thereby, it is possible to automate the detection of the ink flowing into the bypass channel 106.

[Second Embodiment]
Next, a second embodiment will be described. As shown in FIGS. 12 and 13, in this embodiment, compared with the first embodiment, instead of the recovery filtration device 99 and the unused ink filtration device 66, the recovery that is energized when ink flows in the bypass flow path. A filter device 139 for unused ink and a filter device 136 for unused ink are provided. Further, a sensor 140 for detecting energization of the recovery filtration device 139 and a sensor 137 for detecting energization of the unused ink filtration device 136 are provided.

  Since the configuration and operation of the unused ink filtration device 136 and the sensor 137 are the same as those of the recovery filtration device 139 and the sensor 140, when the ink flows into the bypass passage 126, the recovery filtration device 139 is energized. The description of the unused ink filtration device 136 is omitted.

  In the present embodiment, the outer wall 127 of the bypass passage 126 of the recovery filter 139 does not need to be transparent (see FIG. 13).

  The outer wall 127 is provided with two needle-like electrodes 130A and 130B, and the tips of the electrodes 130A and 130B are both exposed to the bypass channel 126. The electrodes 130A and 130B are connected to the sensor 140, and the sensor 140 is connected to the controller 56.

  When the material of the outer wall 127 is a conductive material (for example, SUS), the electrodes 130A and 130B and the outer wall 127 are electrically insulated by an insulating member.

  When ink flows into the bypass flow path 126, the electrodes 130 </ b> A and 130 </ b> B are energized, and a signal indicating the energization is transmitted from the sensor 140 to the controller 56.

  The controller 56 displays that it is time to replace the recovery filtration device 139 by display means (lamp etc.) not shown.

  According to the present embodiment, it is possible to automate detection of ink flowing into the bypass channel 126 with a simple configuration. Further, it is not necessary to make the outer wall 127 transparent.

  The embodiments of the present invention have been described above with reference to the embodiments. However, these embodiments are merely examples, and various modifications can be made without departing from the scope of the invention. Needless to say, the scope of rights of the present invention is not limited to the above embodiment.

It is a front sectional view showing the configuration of the ink jet recording apparatus of the first embodiment in an image recording state. It is a front sectional view showing the composition of the ink jet recording device of a 1st embodiment in a maintenance state. FIG. 2 is a conceptual front view illustrating a configuration of a conveyance belt and its vicinity of the ink jet recording apparatus according to the first embodiment. FIG. 2 is a block diagram illustrating a configuration of a control system of the ink jet recording apparatus according to the first embodiment. It is a schematic diagram which shows the ink flow line of the inkjet recording device of 1st Embodiment. It is side surface sectional drawing of the filtration apparatus for recovery provided in the inkjet recording device of 1st Embodiment. It is typical side surface sectional drawing for demonstrating the contact angle of a meniscus. It is typical side surface sectional drawing for demonstrating the contact angle of a meniscus. FIG. 3 is a schematic side cross-sectional view illustrating an ink flow in a normal state in which the recovery filter device is not clogged in the first embodiment. FIG. 6 is a schematic side cross-sectional view showing the ink flow in a state where the recovery filter is clogged in the first embodiment. It is a fragmentary sectional view showing the modification of a 1st embodiment. It is a schematic diagram which shows the ink flow line of the inkjet recording device of 2nd Embodiment. It is side surface sectional drawing of the filtration apparatus for recovery provided in the inkjet recording device of 2nd Embodiment.

Explanation of symbols

12 Inkjet recording device 33 Inkjet recording head 62 Ink supply line 66 Filtration device for unused ink (filtration device)
88 Cap (liquid receiver)
97 Reuse ink line 98 Recovery operation pump (suction means)
99 Recovery filtration device (filtration device)
104 Main channel 106 Bypass channel 107 Outer wall (outer channel wall)
108 Main filter section (filter section)
110 Clogging detection filter unit 126 Bypass flow path 139 Recovery filter device 136 Unused ink filter device 130A, B electrode

Claims (7)

A filtration device for removing foreign matter in a liquid to be filtered by passing the filter part through the liquid to be filtered,
A main flow path provided with the filter section;
A bypass channel formed in parallel with the main channel and provided with a clogging detection filter unit;
Detection enabling means for enabling detection of the liquid to be filtered flowing into the clogging detection filter unit;
With
The clogging detection filter unit has a liquid repellent surface and a smaller opening diameter than the filter unit.   The filtration device according to claim 1, wherein a contact angle of the liquid to be filtered is 90 ° or more on the surface of the clogging detection filter portion.   The filtration device according to claim 1 or 2, wherein the filter unit and the clogging detection filter unit are integrally formed and detachably integrated with the device.   The transparent enabling flow path wall which forms the said bypass flow path downstream from the said clogging detection filter part is provided as the said detection enabling means, The any one of Claims 1-3 characterized by the above-mentioned. The filtration device according to item.   Any one of Claims 1-3 characterized by arrange | positioning the electrode which supplies with electricity when a to-be-filtered liquid flows into the said bypass flow path downstream from the said filter part for clogging detection as the said detection enabling means. The filtration apparatus of Claim 1. An ink jet recording head for discharging ink droplets;
An ink supply line for supplying ink to the inkjet recording head;
With
An ink jet recording apparatus comprising: the ink supply line including the filtration device according to claim 1. A liquid receiver containing ink from the inkjet recording head;
Suction means for sucking out ink from the ejection surface of the inkjet recording head via the liquid receiver;
With
As the ink supply line, a reusable ink line is provided for flowing part or all of the ink sucked out by the sucking means as ink for reuse,
The inkjet recording apparatus according to claim 6, wherein the filtration apparatus according to claim 1 is provided in the reuse ink line.

Images