JP2014218000A - Ink jet recorder and recovery method of ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make pump recovery easy.SOLUTION: An ink jet recorder comprises a pump 90 for transporting liquid, and the pump 90 comprises a casing 91, a suction side check valve 92 which is arranged at the suction side of the liquid to be transportation and a discharge side check valve 93 which is arranged at the discharge side of the liquid, a regulating valve 94 for regulating the pressure in the casing 91 and performing suction operation of the liquid into the pump 90 and discharge operation of the liquid outside the pump 90, an on-off valve which is connected to the liquid suction side or the liquid discharge side of the casing 91 through a channel and can block the channel, and a control part 30 for controlling the regulating valve 94 and the on-off valve. The control part 30 makes a recovery operation mode which controls the regulating valve 94 and the on-off valve performable so that discharge operation of the liquid outside of the pump 90 is performed by operation of blocking the channel through the on-off valve under a condition that at least any one of the suction side check valve 92 or the discharge side check valve 93 does not operate normally.

Description

  The present invention relates to an inkjet recording apparatus and an inkjet recording apparatus recovery method capable of easily recovering a pump.

  In order to form various printing patterns such as letters and figures for various industrial products, ink jet recording apparatuses are used for industrial and consumer purposes. The inkjet recording device is a non-contact printing method that prints by irradiating ink particles from a distance away from the object to be printed, so it can print on curved surfaces, for example, producing displays such as the expiration date, serial number, and model number. Print non-contact on the object. In particular, continuous (continuous jetting) inkjet recording apparatuses that continuously discharge ink are transported one after another on a production line or the like, as opposed to on-demand inkjet recording apparatuses that discharge ink only when necessary. It has the merit of being able to print products at high speed and using them efficiently and continuously, and is used in various fields.

  An example of the head portion of the continuous ink jet recording apparatus is shown in the schematic cross-sectional view of FIG. A head portion 1406 shown in FIG. 14 includes an injection nozzle 1420, a gutter 1427, a charging electrode 1424, and a deflection electrode 1426 inside a rectangular box-shaped housing 1425. As shown in this figure, the ink jet recording apparatus always ejects ink particles continuously from the ejection nozzle 1420, deflects the ejected ink particles by a necessary amount, and prints it on a print object, thereby obtaining a desired printing pattern. Are formed on the object to be printed. While this ink jet recording apparatus always ejects ink from the ejection nozzle 1420 in a printable state, ink that is not used for printing is collected by the gutter 1427 and reused.

  A liquid supply pipe 1403 is connected to the ejection nozzle 1420, and an ink supply pipe 1447 and a solvent supply pipe 1444 are connected to the liquid supply pipe 1403 by a three-way valve 1414 so as to be switchable. The three-way valve 1414 is a valve that branches three flow paths. In the example of FIG. 14, either the ink supply pipe 1447 or the solvent supply pipe 1444 is switched to and connected to the liquid supply pipe 1403. When the three-way valve 1414 is switched and the ink supply pipe 1447 is connected to the liquid supply pipe 1403, the ink pressurized to a predetermined pressure is introduced into the ejection nozzle 1420. This ink reaches a predetermined speed through a nozzle portion 1401 formed through one peripheral wall of the ejection nozzle 1420 and an ink ejection hole 1402 provided at a position corresponding to the nozzle portion 1401 on the ink delivery surface of the ejection nozzle 1420. Is injected. Further, a gutter 1427 is arranged so as to face the injection nozzle 1420 in the injection direction, and a first recovery pipe 1457 is connected to the gutter 1427. The injection nozzle 1420 is connected to a return path 1433 for releasing the pressure of the head unit 1406 during a falling operation.

  Inside the ejection nozzle 1420, a piezoelectric vibrator 1404 such as a piezoelectric vibrator that vibrates when a high frequency voltage is applied is disposed with the tip of the vibrating piece facing the ink ejection hole 1402, and this piezoelectric vibrator 1404. When the ink is vibrated during the above-described ink ejection, the ink ejected from the head unit 1406 is separated from each other along the ejection path and proceeds as ink particles arranged at a predetermined interval. The charging electrode 1424 and the deflecting electrode 1426 are arranged side by side along such a traveling path of ink particles, the former being arranged at a position where separation into the ink particles occurs, and the latter immediately after the position where separation occurs. It is arranged.

  A voltage controlled in synchronization with separation into the respective ink particles is applied to the charging electrode 1424, and each ink particle passing through the position where the charging electrode 1424 is disposed has a different charge. Charged. In addition, a high-voltage DC voltage is applied to the deflection electrode 1426 to form an electric field having a predetermined intensity, and the ink particles charged by the action of the charging electrode 1424 pass through the position where the deflection electrode 1426 is disposed. At this time, it is deflected according to the respective electric charges by the action of the electric field, sent out through the delivery port 1405 formed in the end wall of the housing 1425, and printed on the print object A facing the delivery port 1405.

  In addition, some of the ink particles ejected from the ejection nozzle 1420 are not charged when passing through the charging electrode 1424, travel straight without being deflected by the action of an electric field, are captured by the gutter 1427, and are captured by the first recovery tube 1457. To be recovered. In this way, on the surface of the printing object A, a combination of dots formed by the ink particles delivered from the delivery port 1405 and blanks formed at corresponding positions of the ink particles captured by the gutter 1427, Desired patterns such as letters and figures can be formed. Ink particles that have not been used for printing fly straight without being deflected, and are collected by a waiting gutter 1427. Further, in order to reuse the collected ink particles, a gutter pump that sucks and discharges the ink particles is provided.

Japanese Patent No. 4762179

  Such a gutter pump is provided with check valves at the suction port and the discharge port in order to prevent the backflow of ink. For example, when the gutter pump is a diaphragm pump, a ball check valve is used as the check valve. As an example, the operation examples of the diaphragm pump are shown in the schematic cross-sectional views of FIGS. 15A to 15D. This diaphragm pump includes a casing 91 for defining an internal space, a suction-side check valve 95, a discharge-side check valve 96, a diaphragm 94A that separates the internal space from the external space, and the diaphragm 94A from the outside. And an eccentric cam rotating mechanism 98 for pressing. The eccentric cam rotation mechanism 98 adjusts the amount of pressure applied to the diaphragm 94A, thereby changing the internal pressure of the inner space of the diaphragm pump to perform suction and discharge operations. The eccentric cam rotating mechanism 98 is fixed to the rotating shaft of the motor and periodically driven, thereby periodically deforming the diaphragm 94A and continuously performing the suction process and the discharging process.

  A procedure for sucking and discharging ink with this diaphragm pump will be described with reference to schematic sectional views of FIGS. 15A to 15D. First, as shown in FIG. 15A, in the suction process, the diaphragm 94A is gradually expanded to lower the internal pressure, the discharge-side check valve 96 is closed, and the suction-side check valve 95 is opened, so that the ink Aspirate. As shown in FIG. 15B, when the expansion of the diaphragm 94A is maximized, the suction is stopped and the suction-side check valve 95 is closed. Next, as shown in FIG. 15C, when the contraction of the diaphragm 94A is started, the internal pressure is gradually increased, so that the discharge-side check valve 96 is opened while the suction-side check valve 95 is closed. Allow the valve to start dispensing. Then, as shown in FIG. 15D, when the contraction of the diaphragm 94A becomes maximum, the increase of the internal pressure is stopped, and the discharge-side check valve 96 is closed. Thereafter, by repeating the operations of FIGS. 15A to 15D, the pump operation is continued so that the ink sucked from the suction port is ejected from the ejection port without flowing backward.

  The above diaphragm type pump uses a ball type check valve as a check valve. As shown in FIG. 16A, the ball check valve includes a ball 1601 and its valve seat 1602. Here, a slight gap is formed between the ball 1601 and the valve seat 1602. If the liquid is transported by this pump, the presence of the gap is not a problem because the liquid fills the gap. However, when the gas is transported, the gas leaks from the gap, so that the transport capability is impaired and the flow rate is extremely reduced.

  In other words, once the liquid has been lost from the pump for some reason and dried, it becomes difficult to start the pump again. In this case, conventionally, when a liquid is poured from the outside by some method like “priming water”, it can be started.

  Here, in the gutter pump of the ink jet recording apparatus, the target to be originally sucked is a gas-liquid mixed fluid. In other words, there is relatively little liquid. Furthermore, if the ink jet recording apparatus is left unused for a long time, this liquid tends to dry, and the pump may not start.

  In particular, ink used in an ink jet recording apparatus is often easily dried so that printing can be performed clearly and smoothly. In addition, since the check valve on the suction side of the gutter pump is exposed to the outside air, the ink tends to dry. As the ink dries and hardens, the check valve ball can become locked. At this time, the check valve may be fixed in the open state. For example, from the state where the ball 1601 as shown in FIG. 16A is in a normal position and the valve is closed, as shown in FIG. 16B, the ball 1601 is inclined and the gap GP is formed. It may be fixed. In addition, as described above, there is a slight gap between the ball 1601 and the valve seat 1602 constituting the check valve, and the check valve is fixed without being closed. Can happen.

  In such a state, normal suction and discharge operations cannot be performed. This will be described with reference to FIGS. 17A to 17D. For the sake of explanation, the adjustment mechanism for expanding and contracting the diaphragm 1794 is not shown. First, as shown in FIG. 17A, in the suction process, the diaphragm 1794 is expanded to lower the internal pressure, the discharge side check valve 1796 is closed, and the suction side check valve 1795 is opened to suck ink. . This operation itself can be performed through the clearance of the suction side check valve 1795. Next, as shown in FIG. 17B, when the expansion of the diaphragm 1794 is maximized, the suction side check valve 1795 is completely closed when the suction is stopped and the suction side check valve 1795 is closed. It is not possible. Now, transitioning to FIG. 17C, when contraction of the diaphragm 1794 is started to gradually increase the internal pressure and the discharge side check valve 1796 is opened to start discharge, the discharge side check valve 1796 side In addition, the ink is discharged from the suction side check valve 1795 side. That is, ink flows backward and normal pump operation does not work. As shown in FIG. 15D, even when the diaphragm 1794 contracts to the maximum, the discharge-side check valve 1796 is closed, but the suction-side check valve 1795 is not closed. As a result, the ink sucked at the corner is returned to the reverse from the same place, and the gutter pump cannot be operated normally.

  When this state occurs, there is a problem that it is difficult to start and restore the ink jet recording apparatus. As described above, if `` priming water '' that flows liquid such as replenisher or ink into the gutter pump can be introduced, recovery of the pump operation can be expected, but when the check valve is opened, the introduced liquid Since it leaks, it is difficult to introduce the liquid as it is. For this reason, an operation for forcibly pushing in the liquid by some method is required, and the work becomes considerably difficult. Alternatively, it was sometimes necessary to replace the equipment itself. For this reason, there has been a strong demand for a method that can smoothly restore the liquid when such a pump is dried.

  The present invention has been made to solve such conventional problems. A main object of the present invention is to provide an ink jet recording apparatus and a method for recovering an ink jet recording apparatus that can easily recover a pump.

Means for Solving the Problems and Effects of the Invention

  In order to achieve the above object, according to the ink jet recording apparatus according to the first aspect of the present invention, there is provided a continuous ink jet recording apparatus that causes ink to fly and adhere to a recording object and collect unused ink. An ink tank for storing ink and a pump for transporting the ink or a liquid containing a replenisher for diluting the ink, the pump being a casing and a transport object of the casing A suction-side check valve that is disposed on the liquid suction side and that allows the liquid to flow only in the direction of sucking the liquid, and that is disposed on the liquid discharge side of the casing and that causes the liquid to flow only in the direction of discharging the liquid. A discharge side check valve for adjusting the pressure in the casing, and a regulating valve for performing a liquid suction operation into the pump and a liquid discharge operation outside the pump The ink jet recording apparatus further includes an on-off valve connected to the liquid suction side or the liquid discharge side of the casing via the flow path, which can shut off the flow path, and the adjustment valve and the on-off valve. A control unit for controlling the flow rate, and the control unit shuts off the flow path with the on-off valve when at least one of the suction-side check valve and the discharge-side check valve does not operate normally. The recovery operation mode for controlling the regulating valve and the on-off valve can be executed so that the liquid is discharged outside the pump. With the above configuration, even when the check valve of the pump does not function, the pump can be operated and recovered by performing the closing and opening operations with the control valve by the on-off valve connected to the pump.

  In the ink jet recording apparatus according to the second aspect of the invention, the control unit matches the opening / closing operation of the on-off valve with the operation timing of the suction side check valve or the discharge side check valve of the pump. Thus, the operations of the on-off valve and the regulating valve can be controlled. With the above configuration, the operation of the suction side check valve and the discharge side check valve on the pump side and the opening / closing operation of the on / off valve can be linked to efficiently execute the recovery operation mode.

  Further, according to the ink jet recording apparatus of the third invention, the on-off valve is connected to the suction side check valve, the control unit expands the adjustment valve, and the discharge side check valve is By closing the valve and opening the on-off valve, the pressure in the casing is reduced to suck liquid into the pump, and the on-off valve is closed with the adjustment valve expanded. The adjusting valve is contracted, the discharge-side check valve is opened, the liquid is discharged from the pump, and the discharge-side check valve is closed while the adjusting valve is contracted. It can be controlled to repeat in order. With the above configuration, even when the suction check valve of the pump does not function, the liquid can be introduced into the pump by performing the closing and opening operation with the on-off valve connected to the suction side of the pump. Therefore, the operation of the pump can be smoothly restored by the action of the priming water.

  Furthermore, according to the ink jet recording apparatus of the fourth aspect of the invention, the on-off valve is connected to the discharge-side check valve, and the control unit expands the adjustment valve, so that the suction-side check valve Is opened, and the on-off valve is closed to reduce the pressure in the casing to suck liquid into the pump, and the adjustment valve is expanded to close the on-off valve. In this state, the suction side check valve is closed, the adjustment valve is contracted, the opening / closing valve is opened, liquid is discharged from the pump, and the opening / closing operation is performed while the adjustment valve is contracted. It can control to repeat the operation of closing the valve in order. With the above configuration, even when the discharge side check valve of the pump does not function, the liquid can be introduced into the pump by performing the closing and opening operation with the on-off valve connected to the discharge side of the pump. Therefore, the operation of the pump can be smoothly restored by the action of the priming water.

  Furthermore, according to the ink jet recording apparatus of the fifth invention, the on-off valve can be provided on the liquid suction side and the liquid discharge side of the casing, respectively. With the above configuration, it is possible to substitute the functions of both the suction-side check valve and the discharge-side check valve using a plurality of on-off valves, and both the suction-side check valve and the discharge-side check valve cannot operate. Even in this case, the ink jet recording apparatus can be restored.

  Furthermore, according to the ink jet recording apparatus of the sixth aspect of the invention, the control unit can be controlled to execute the recovery operation mode at a predetermined timing set in advance. For example, by causing the recovery operation to be performed when the ink jet recording apparatus is finished or started, it is possible to constantly maintain a usable state without making the user aware of the recovery operation.

  Furthermore, according to the ink jet recording apparatus of the seventh aspect of the invention, the control unit can be configured to accept an instruction for executing the recovery operation mode at an arbitrary timing from the outside.

  Furthermore, according to the ink jet recording apparatus of the eighth invention, the pump can be a gutter pump.

  Furthermore, according to the ink jet recording apparatus according to the ninth aspect of the present invention, the adjustment valve can be constituted by a diaphragm.

  Furthermore, according to the ink jet recording apparatus of the tenth aspect, the on-off valve can be an electromagnetic valve.

  Furthermore, according to the ink jet recording apparatus of the eleventh aspect, the electromagnetic valve can be used also as an electromagnetic valve for opening the flow path when the ink jet recording apparatus is in operation and closing the flow path when the ink jet recording apparatus is not operating. With the above configuration, the electromagnetic valve provided in the ink jet recording apparatus can be used also as an electromagnetic valve for pump recovery operation, and the pump recovery function can be realized at low cost by using existing equipment.

  Furthermore, according to the ink jet recording apparatus of the twelfth aspect, the ink tank can be connected to the discharge side of the pump. The above configuration makes it difficult for the discharge-side check valve connected to the discharge side of the pump to dry the liquid, while the dry-side check valve connected to the pump suction side prevents the liquid from drying. It becomes possible to restore this smoothly using the on-off valve.

  Furthermore, according to the ink jet recording apparatus recovery method of the thirteenth aspect of the present invention, the ink of the continuous ink jet recording apparatus that causes ink to fly and adhere to a recording object and collect unused ink. Or a recovery method for recovering the operation of the pump when the pump for transporting the replenisher for diluting the ink does not operate, the adjustment valve of the pump being expanded, and the pump, A discharge-side check valve that is arranged on the liquid discharge side and allows the liquid to flow only in the direction of discharging the liquid, and opens the on-off valve connected to the liquid suction side of the pump; A step of sucking liquid into the pump; a step of closing the on-off valve in a state in which the adjustment valve is expanded; and a contraction of the adjustment valve in a state in which the on-off valve is closed. And repeating the steps of opening the discharge-side check valve and discharging the liquid from the pump, and closing the discharge-side check valve while the adjustment valve is contracted. Can do. As a result, even if the suction side check valve of the pump does not function, liquid can be introduced into the pump by performing the closing and opening operation with the on-off valve connected to the suction side of the pump. Therefore, the operation of the pump can be smoothly restored by the action of the priming water.

  Furthermore, according to the method for recovering an ink jet recording apparatus according to the fourteenth aspect of the present invention, the ink of the continuous ink jet recording apparatus that causes ink to fly and adhere to a recording object and collect unused ink. Or a recovery method for recovering the operation of the pump when the pump for transporting the replenisher for diluting the ink does not operate, the adjustment valve of the pump being expanded, and the pump, A suction side check valve which is arranged on the liquid suction side and allows the liquid to flow only in the direction of sucking the liquid, and the on-off valve connected to the liquid discharge side of the pump is closed. A step of sucking liquid into the pump, a step of closing the suction side check valve while the open / close valve is closed in a state where the adjustment valve is expanded, and the suction side check valve In the closed state, the adjusting valve is contracted and the on-off valve is opened to discharge the liquid from the pump; and the on-off valve is closed in the contracted state. And the step of making them can be repeated in order. Thus, even if the discharge check valve of the pump does not function, the liquid can be introduced into the pump by performing the closing and opening operation with the on-off valve connected to the discharge side of the pump. Therefore, the operation of the pump can be smoothly restored by the action of the priming water.

1 is a perspective view showing an ink jet recording apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional perspective view and a main part enlarged view of a head portion of the ink jet recording apparatus of FIG. 1. FIG. 4 is a route diagram illustrating a route of ink or the like of the inkjet recording apparatus. It is the perspective view which looked at the pump unit from the back side. 5A to 5D are schematic cross-sectional views showing the operation of the pump according to Embodiment 1. FIG. 6A to 6D are schematic cross-sectional views illustrating the operation of the pump according to the second embodiment. 7A to 7D are schematic cross-sectional views illustrating the operation of the pump according to the third embodiment. It is a block diagram which shows the example of a connection of a control part. It is the graph which showed the time change of the volume of a pump, and the valve opening period of the attraction | suction side solenoid valve. It is the graph which showed the time change of the volume of a pump, and the valve opening period of a suction side solenoid valve and a discharge side solenoid valve. In Embodiment 2, it is a flowchart which shows the procedure which instruct | indicates opening and closing of a solenoid valve. It is a flowchart which shows the procedure which opens / closes a suction side solenoid valve. It is a flowchart which shows the procedure which opens / closes a discharge side solenoid valve. FIG. 2 is a schematic diagram illustrating a configuration of a head unit of a continuous ink jet recording apparatus. 15A to 15D are schematic cross-sectional views showing the normal operation of the diaphragm pump. FIG. 16A is a schematic cross-sectional view showing a state where the check valve is closed, and FIG. 16B is a schematic cross-sectional view showing a state where the ball is hardened and cannot be closed. FIG. 17A to FIG. 17D are schematic cross-sectional views illustrating the operation of the diaphragm pump when it is abnormal.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiments described below exemplify an ink jet recording apparatus and an ink jet recording apparatus for embodying the technical idea of the present invention. The present invention includes the following ink jet recording apparatus and ink jet recording apparatus. Not specified. Further, the present specification by no means specifies the members shown in the claims to the members of the embodiments. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in the embodiments are not intended to limit the scope of the present invention unless otherwise specified, and are merely explanations. It's just an example. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and symbol indicate the same or the same members, and detailed description thereof will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and the plurality of elements are shared by one member, and conversely, the function of one member is constituted by a plurality of members. It can also be realized by sharing.

  A configuration example of the inkjet recording apparatus 100 according to Embodiment 1 of the present invention is shown in the perspective view of FIG. The ink jet recording apparatus 100 includes a head section 6 and an ink jet recording apparatus main body 4 connected to the head section 6 and including an ink supply pipe, various paths, a tank, a pump, and the like. The head unit 6 is configured to be connected to the main body 4 of the ink jet recording apparatus 100 by a flexible hose 5 so as to be arranged at a position different from the ink jet recording apparatus main body 4. In the example of FIG. 1, the ink jet recording apparatus 100 is applied to a production line and shows a state. The ink jet recording apparatus 100 is disposed, for example, on a belt conveyor 2 in a factory, and ejects ink particles while appropriately deflecting the surface of an object 3 such as a container for food conveyed on the belt conveyor 2. Thus, it is a so-called continuous type ink jet recording apparatus capable of recording desired characters such as date of manufacture and other figures.

  The ink jet recording apparatus 100 includes a main body 4 containing ink, a head unit 6 connected to the main body 4 via a flexible hose 5, and an operation display unit connected to the main body 4 via a wiring cable 7. 8 and. The main body 4 accommodates various members such as a main tank for storing ink and an ink pump for sending ink in the main tank in a hollow rectangular parallelepiped main body housing 9. A control unit (not shown in FIG. 1) including a processor is provided in the main body housing 9, and each unit such as an ink pump is controlled by the control unit.

  The ink used in the ink jet recording apparatus 100 is generated, for example, by mixing a dye with methyl ethyl ketone, which is a volatile solvent. By replenishing this ink with a volatile solvent made of methyl ethyl ketone as a replenisher, the concentration of the ink is adjusted, and the ink having an appropriate viscosity is sent to the head unit 6 via the flexible hose 5. It is like that.

  An organic solvent can also be used as the volatile solvent. However, in consideration of the environment and the like, it is also desirable to use a water-soluble solvent such as alcohol without using an organic solvent. In the present invention, the solvent is not limited to a volatile solvent, and a non-volatile solvent can also be used. The ink used has a higher viscosity than the solvent.

  The head unit 6 is disposed so as to face the conveyance path of the object 3, and injects the ink sent from the main body 4 via the flexible hose 5 into the particle form and ejects the ink onto the object 3. The head unit 6 can be installed at a desired distance and angle with respect to the conveyance path of the object 3 by appropriately bending the flexible hose 5. The ink formed into particles in the head unit 6 is charged in the head unit 6 and an electric field is formed in the travel path of the charged ink particles, whereby the ink particles are deflected by a deflection amount corresponding to the charge amount. Then, it is injected to the object 3.

  Signals from input devices such as the speed detection sensor 13 and the passage detection sensor 14 are input to the main body 4. The speed detection sensor 13 detects the conveyance speed of the object 3 based on the rotation speed of the belt conveyor 2. The passage detection sensor 14 optically detects the object 3 passing on the transport path in a non-contact manner. The control unit provided in the main body 4 controls the charge amount of the ink particles ejected from the head unit 6 based on the input signals from the speed detection sensor 13 and the passage detection sensor 14, so that the desired object 3 can be obtained. A desired character or figure can be recorded at the position.

  The operation display unit 8 is formed by a liquid crystal display with a touch panel, can perform a predetermined display on the display screen, and can be operated by a user touching the display screen. Control of the control unit in the main body 4 can be set by the user by operating the operation display unit 8. The operation display unit 8 can be installed at a position away from the main body 4 by extending the wiring cable 7, that is, a position away from the conveyance path of the object 3, and ink jet recording can be performed by operating the operation display unit 8. The apparatus 100 can be remotely operated.

  A control device such as a personal computer 15 or a programmable controller 16 can be connected to the main body 4. The ink jet recording apparatus 100 can operate based on an operation of the operation display unit 8 or can operate based on a control signal from a control device as an external connection device. Further, an output device such as a rotating lamp 17 or a buzzer 18 can be connected to the main body 4. When an abnormality occurs on the production line, the abnormality notification can be performed by operating these output devices.

  FIG. 2 is a perspective view showing the internal configuration of the head unit 6 of FIG. In this figure, a part of the outer surface of the head portion 6 is omitted. In the head unit 6, a pressurizer 22, a nozzle 23, a charging electrode 24, a charging detection sensor 25, a deflection electrode 26, and a gutter 27 are provided. The ink sent from the main body 4 to the head unit 6 is pressurized by the pressurizer 22 and ejected from the nozzle 23.

  The nozzle 23 includes a piezo vibration element (not shown), and ink is ejected while receiving vibration by the piezo vibration element. As schematically shown in FIG. 2, the charging electrode 24 includes a pair of electrode plates 24 a and 24 b arranged to face each other, and a positive potential is applied to the electrode plates 24 a and 24 b from the nozzle 23. By ejecting ink between the electrode plates 24a and 24b, ink particles charged to a negative potential are continuously ejected. The charge detection sensor 25 is for detecting whether the ink particles that have passed through the charging electrode 24 are normally charged.

  The deflection electrode 26 includes a pair of electrode plates 26a and 26b arranged to face each other, and a traveling path of ink particles charged by the charging electrode 24 is formed between the pair of electrode plates 26a and 26b. Yes. One electrode plate 26 a extends in parallel with the direction in which the ink particles travel from the nozzle 23. On the other hand, the other electrode plate 26b is inclined obliquely so that the downstream end with respect to the traveling direction of the ink particles moves away from the one electrode plate 26a toward the downstream side.

  A high voltage of about 7 kV is applied to the pair of electrode plates 26a and 26b of the deflection electrode 26, whereby an electric field is formed between the pair of electrode plates 26a and 26b. Accordingly, the ink particles charged by the charging electrode 24 change the traveling direction by receiving a force corresponding to the amount of charge from the electric field in the process of passing between the pair of electrode plates 26a, 26b of the deflection electrode 26, The light is deflected by a deflection amount corresponding to the charge amount.

  Each ink particle that has passed through the deflection electrode 26 is ejected to the object 3 through the ejection port 28. As shown in FIG. 2, while transporting the object 3 in a certain direction, the ink particles are appropriately deflected and ejected in a direction orthogonal to the transport direction, thereby causing a two-dimensional surface on the surface of the object 3. Characters and figures can be recorded. Ink particles that have not been deflected by the deflection electrode 26 travel straight along the one electrode plate 26 a and are collected by the gutter 27. The ink collected by the gutter 27 is sent back from the head unit 6 to the main body 4 via the flexible hose 5 and is supplied from the main body 4 to the head unit 6 after the replenisher is replenished to adjust the concentration. Reused as ink.

  Next, FIG. 3 shows a route diagram showing the route of ink or the like in the inkjet recording apparatus 100. The main body 4 shown in this figure is provided with various tanks such as an ink tank 31, a replenisher tank 32, a main tank 33, and a conditioning tank 34.

  In the ink tank 31, the user can store a predetermined amount of ink in advance. In the replenisher tank 32, the user can store a replenisher to a certain amount in advance. The main tank 33 can store ink whose density has been adjusted by replenishing ink with a replenisher. By feeding the ink whose density has been adjusted in the main tank 33 to the head unit 6, it is possible to record characters and figures on the object 3 with an appropriate density.

  In the ink jet recording apparatus 100, the replenisher stored in the replenisher tank 32 is sent to the head unit 6 as it is, so that each part in the head unit 6 can be cleaned using the replenisher. . The replenisher used for the cleaning is collected by the gutter 27, sent back to the main body 4, and stored in the conditioning tank 34. The used replenisher stored in the conditioning tank 34 is supplied to the main tank 33 as needed, and is reused for ink density adjustment.

  The main tank 33 and the conditioning tank 34 communicate with the outside of the main body housing 9 through the exhaust pipe 35, and the gas filled in the main tank 33 and the conditioning tank 34 is introduced into the atmosphere through the exhaust pipe 35. It can be exhausted.

  An ink circulation pipe 36 for circulating the ink in the main tank 33 is connected to the main tank 33. The ink circulation pipe 36 is provided with a circulation supply switching valve V5, a circulation pump 37, and a circulation delivery switching valve V11 in this order along the ink flow direction. The circulation supply switching valve V5 and the circulation delivery switching valve V11 are arranged in this order. By driving the circulation pump 37 with the valve V11 opened, the ink in the main tank 33 can be circulated through the ink circulation pipe 36.

  A circulation filter 38 is interposed between the circulation supply switching valve V 5 and the circulation pump 37 in the ink circulation pipe 36. The circulation filter 38 is for capturing foreign matter contained in the ink flowing in the ink circulation pipe 36, and can capture foreign matter of 40 μm or more.

  In addition, a viscometer 39 for taking in a part of the ink flowing in the ink circulation pipe 36 and detecting the viscosity of the ink is interposed on the downstream side of the circulation delivery switching valve V11 in the ink circulation pipe 36. Yes. Based on the viscosity of the ink detected by the viscometer 39, the concentration of the ink in the main tank 33 can be detected.

  The ink in the ink tank 31 flows into the main tank 33 through the ink inflow pipe 40. The ink inflow pipe 40 is connected to the upstream side of the circulation pump 37 in the ink circulation pipe 36, more specifically, the upstream side of the circulation filter 38, via the ink inflow switching valve V 8. Accordingly, by driving the circulation pump 37 with the ink inflow switching valve V8 and the circulation delivery switching valve V11 being opened, the ink in the ink tank 31 is transferred to the main tank 33 via the ink inflow pipe 40 and the ink circulation pipe 36. Can be allowed to flow into.

  An ink tank filter 41 for capturing foreign matter contained in the ink supplied from the ink tank 31 is interposed in the ink inflow tube 40 so that foreign matter of 40 μm or more can be captured. .

  The replenisher in the replenisher tank 32 flows into the main tank 33 through the replenisher inflow pipe 42. A replenisher pump 43 and a replenisher inflow switching valve V13 are provided in the replenisher inflow pipe 42 in this order along the flow direction of the replenisher, and replenishment is performed with the replenisher inflow switching valve V13 open. By driving the liquid pump 43, the replenisher in the replenisher tank 32 can flow into the main tank 33. An upstream side of the replenisher liquid pump 43 in the replenisher liquid inflow pipe 42 is a replenisher liquid supply pipe 44 for supplying the replenisher liquid from the replenisher liquid tank 32 to the replenisher liquid pump 43.

  A replenisher tank filter 45 is interposed in the replenisher inflow pipe 42 upstream of the replenisher pump 43, that is, in the replenisher liquid supply pipe 44. A replenisher main filter 46 is interposed in the replenisher inflow pipe 42 downstream of the replenisher pump 43, more specifically, between the replenisher pump 43 and the replenisher inflow switching valve V13. The replenisher tank filter 45 and the replenisher main filter 46 are for capturing foreign substances contained in the replenisher flowing in the replenisher inflow pipe 42, and can capture foreign matters of 40 μm or more.

  When the ink jet recording apparatus 100 is used, the ink in the ink tank 31 is supplied to the main tank 33 via the ink inflow pipe 40, and the replenishment liquid in the replenishment liquid tank 32 passes through the replenishment liquid inflow pipe 42. By supplying to the main tank 33, ink whose density is adjusted is generated in the main tank 33. At this time, the ink in the main tank 33 is circulated through the ink circulation pipe 36, the concentration is detected from the output of the viscometer 39, and an amount of replenisher corresponding to the detected concentration is supplied into the main tank 33. Thus, the ink density can be adjusted satisfactorily.

  The ink in the main tank 33 is supplied to the ink pump 48 via the ink supply pipe 47, and the ink delivered from the ink pump 48 is guided to the head unit 6 via the ink delivery pipe 49. The ink delivery tube 49 extends from the main body 4 through the flexible hose 5 to the head unit 6, and the tip of the ink delivery tube 49 is connected to an ejection switching valve V <b> 14 provided in the head unit 6. .

  A pressure reducing valve 50 and a pressure gauge 51 are interposed in this order along the ink flow direction at a portion of the ink delivery pipe 49 on the main body 4 side. The pressure reducing valve 50 is for expanding the flow path and reducing the pressure when the pressure of the ink in the ink delivery pipe 49 is too high. The pressure gauge 51 detects the pressure of ink in the ink delivery pipe 49, particularly on the downstream side of the pressure reducing valve 50. The discharge pressure of the ink pump 48 is adjusted according to the pressure detected by the pressure gauge 51. can do.

  An ink main filter 52 is interposed downstream of the ink pump 48 in the ink delivery pipe 49, more specifically, between the ink pump 48 and the pressure reducing valve 50. The ink main filter 52 is for capturing foreign matter contained in ink supplied from the ink pump 48 to the head unit 6 via the ink delivery tube 49, and can capture foreign matter of 10 μm or more. Further, the ink delivery tube 49 is provided with 53 in the head portion 6 so that foreign matters contained in the ink before being ejected from the nozzles 23 can be captured. The pre-ejecting ink filter 53 can capture foreign matters of 20 μm or more.

  The replenisher supplied from the replenisher pump 43 is supplied to the head unit 6 at the downstream side of the replenisher pump 43 in the replenisher inflow pipe 42, more specifically between the replenisher main filter 46 and the replenisher inflow switching valve V13. A replenisher feeding pipe 54 for guiding is connected so as to branch. The replenisher liquid delivery pipe 54 extends from the main body 4 through the flexible hose 5 to the head part 6, and the front end of the replenisher liquid delivery pipe 54 is connected to an injection switching valve V <b> 14 provided in the head part 6. ing.

  A replenisher liquid delivery switching valve V12 and a pressure reducing valve 55 are interposed in this order along the flow direction of the replenisher liquid at a portion of the replenisher liquid delivery pipe 54 on the main body 4 side. The pressure reducing valve 55 is for expanding the flow path and reducing the pressure when the pressure of the replenisher in the replenisher delivery pipe 54 is too high. If the replenisher pump 43 is driven in a state where the replenisher inflow switching valve V13 is closed and the replenisher delivery switching valve V12 is opened, the replenisher in the replenisher tank 32 is supplied to the head portion via the replenisher delivery pipe 54. 6 can be supplied.

  The replenishing liquid delivery pipe 54 is provided with a pre-injection replenishing liquid filter 56 in the head unit 6 so that foreign matter contained in the replenishing liquid before being ejected from the nozzle 23 can be captured. Yes. This pre-injection replenisher solution filter 56 can capture foreign matters of 20 μm or more. If the ejection switching valve V14 is switched, either the ink from the ink delivery pipe 49 or the replenishment liquid from the replenishment liquid delivery pipe 54 can be selectively supplied to the nozzles 23.

  The ink collected by the gutter 27 of the head unit 6 is collected from the head unit 6 to the main body 4 via the ink collection tube 57. The ink collection pipe 57 extends from the head portion 6 through the flexible hose 5 to the main body 4, and the tip of the ink collection pipe 57 is connected to the main tank 33. A gutter inflow switching valve V10, a gutter filter 58, a gutter pump 59, and a recovered ink supply switching valve V1 are interposed in this order along the direction of ink flow in the main body 4 side of the ink recovery pipe 57. By driving the gutter pump 59 with the gutter inflow switching valve V10 and the recovered ink supply switching valve V1 opened, the ink recovered from the head unit 6 can be sent to the main tank 33. The gutter filter 58 is for capturing foreign matter contained in the ink flowing in the ink collection tube 57, and can capture foreign matter of 40 μm or more.

  However, the ink recovered from the head unit 6 is not limited to a configuration in which the ink is sent to the main tank 33, but is stored in a recovery ink tank provided separately from the main tank 33, and from the recovery ink tank to the main tank 33. It may be supplied inside.

  When the ink jet recording apparatus 100 is started up or shut down, the replenisher is ejected from the nozzle 23 so that each part in the head unit 6 such as the nozzle 23, the charging electrode 24, and the deflection electrode 26 uses the replenisher. Washed. The replenisher used for the cleaning is recovered by the gutter 27 and recovered from the head unit 6 to the main body 4 via the ink recovery tube 57.

  Connected to the conditioning tank 34 is a recovered replenisher supply pipe 60 for supplying the replenisher recovered from the head unit 6 into the conditioning tank 34. The collection replenisher supply pipe 60 is connected to the downstream side of the gutter pump 59 in the ink collection pipe 57 via the collection replenisher supply switching valve V3. Accordingly, by driving the gutter pump 59 with the gutter inflow switching valve V10 and the recovered replenisher supply switching valve V3 open, the recovered replenisher is supplied to the conditioning tank via the ink recovery pipe 57 and the recovered replenisher supply pipe 60. 34 can be supplied.

  The replenisher in the conditioning tank 34 flows into the main tank 33 through the recovered replenisher inflow pipe 61. The recovery replenisher inflow pipe 61 is connected to the upstream side of the circulation pump 37 in the ink circulation pipe 36, more specifically, the upstream side of the circulation filter 38 via the recovery replenisher inflow switching valve V 9. Accordingly, by driving the circulation pump 37 with the recovered replenisher inflow switching valve V9 and the circulation delivery switching valve V11 being opened, the replenishment in the conditioning tank 34 is performed via the recovered replenisher inflow pipe 61 and the ink circulation pipe 36. The liquid can flow into the main tank 33.

  When the replenisher liquid collected from the head unit 6 is stored in the conditioning tank 34, the replenisher liquid stored in the conditioning tank 34 has priority over the replenisher liquid in the replenisher liquid tank 32 in the main tank 33. The ink is supplied and used for adjusting the density of the ink.

  The liquid stored in the ink tank 31, the replenisher tank 32, the main tank 33, and the conditioning tank 34 can be drained to the outside of the main body housing 9 through the drain pipe 62. A drainage cap (not shown) is formed at the tip of the drainage pipe 62. By attaching the drainage cap to the drainage bottle and draining, liquid can be stored in the drainage bottle. it can. The drainage pipe 62 is connected to the downstream side of the gutter pump 59 in the ink recovery pipe 57 via the drainage switching valve V4. Further, the connection pipe 63 connects between the gutter pump 59 and the drainage switching valve V4 in the ink recovery pipe 57 and between the circulation pump 37 and the circulation delivery switching valve V11 in the ink circulation pipe 36.

  Therefore, if the circulation pump 37 is driven in a state where the circulation delivery switching valve V11 is closed and the ink inflow switching valve V8 and the drainage switching valve V4 are opened, the ink inflow pipe 40, the ink circulation pipe 36, the connection pipe 63, The ink in the ink tank 31 can be drained through the ink recovery tube 57 and the drainage tube 62. Further, if the circulation pump 37 is driven in a state where the circulation delivery switching valve V11 is closed and the circulation supply switching valve V5 and the drainage switching valve V4 are opened, the ink circulation pipe 36, the connection pipe 63, the ink recovery pipe 57, and The ink in the main tank 33 can be drained through the drain pipe 62.

  When the ink in the main tank 33 is drained, the replenisher liquid inflow switching valve V13 is opened and the replenisher liquid pump 43 is driven to replenish the replenisher liquid in the replenisher liquid tank 32 from the replenisher liquid inflow pipe 42. The ink can be drained together with the ink in the main tank 33. If the circulation pump 37 is driven in a state where the circulation delivery switching valve V11 is closed and the recovered replenisher inflow switching valve V9 and the drainage switching valve V4 are opened, the recovered replenisher inflow pipe 61, the ink circulation pipe 36, and the connection pipe 63, the replenisher in the conditioning tank 34 can be drained through the ink recovery pipe 57 and the drain pipe 62.

  An ink return pipe 64 for sending ink in the ink delivery pipe 49 back to the main tank 33 between the ink pump 48 and the ink main filter 52 and the pressure reducing valve 50 in the ink delivery pipe 49. Is connected. The ink return pipe 64 communicates with the main tank 33, and an ink return switching valve V2 is interposed in the middle thereof. When the ink in the main tank 33 is drained, if the ink return switching valve V2 is opened, the ink in the ink delivery pipe 49 communicating with the head portion 6 is caused to flow from the ink return pipe 64 into the main tank 33, and the main tank 33 is discharged. The ink in the tank 33 can be drained.

  An ink sub-filter 65 is interposed downstream of the connection portion of the ink delivery tube 49 with the ink return tube 64, more specifically between the connection portion and the pressure reducing valve 50. The ink sub-filter 65 is for capturing foreign matter contained in the ink sent back from the ink delivery pipe 49 to the main tank 33 via the ink return pipe 64, and can catch foreign matters of 40 μm or more.

  An air circulation pipe 66 is connected to the upstream side of the circulation pump 37 in the ink circulation pipe 36, more specifically, the upstream side of the circulation filter 38 via an air circulation switching valve V 6. The air circulation pipe 66 extends from the main body 4 through the flexible hose 5 to the head part 6, and the tip of the air circulation pipe 66 is connected to the nozzle 23 provided in the head part 6. When the ink jet recording apparatus 100 is lowered, for example, the air circulation switching valve V6 and the drainage switching valve V4 are opened, so that the air circulation pipe 66, the ink circulation pipe 36, the connection pipe 63, the ink recovery pipe 57, and the drainage liquid. The nozzle 23 can be communicated with the atmosphere via the pipe 62. Therefore, by running air between the main body 4 and the head portion 6 and adjusting the ejection pressure of the ink particles ejected from the nozzles 23, the ink can be cut off.

  The operations of the pumps such as the circulation pump 37, the replenisher pump 43, the ink pump 48, and the gutter pump 59 are controlled by the control unit 30 provided in the main body 4. Further, the recovered ink supply switching valve V1, the ink return switching valve V2, the recovered replenishment liquid supply switching valve V3, the drainage switching valve V4, the circulation supply switching valve V5, the air flow switching valve V6, the ink inflow switching valve V8, the recovery replenishing liquid. The operation of each switching valve such as the inflow switching valve V9, the gutter inflow switching valve V10, the circulation / feeding switching valve V11, the replenishing liquid sending switching valve V12, the replenishing liquid inflow switching valve V13, and the injection switching valve V14 is controlled by the control unit 30. The Detection signals from the viscometer 39 and the pressure gauge 51 are input to the control unit 30.

  The booster circuit 73 is connected to the charging electrode 24, the deflection electrode 26, and the injection switching valve V <b> 14 via a wiring that extends through the flexible hose 5 to the head unit 6. The booster circuit 73 boosts the supply voltage from the control unit 30 and sends it to the head unit 6, and supplies the voltage to each part in the head unit 6 such as the charging electrode 24 and the deflection electrode 26. For example, a voltage of 15 V is supplied to the booster circuit 73 from the control unit 30, and this supply voltage is boosted to about 7 kV by the booster circuit 73, and is supplied to the charging electrode 24 and the deflection electrode 26 via the high-voltage power supply line 29. It has come to be given.

  FIG. 4 shows a perspective view of the pump unit 80 viewed from the back side. The pump unit 80 holds a circulation pump 37, a replenisher pump 43, an ink pump 48, a gutter pump 59 and a pump motor 84 for driving these pumps integrally in a box-shaped casing 83 having a rectangular parallelepiped shape. ing.

  More specifically, the replenisher pump 43 and the ink pump 48 are attached to the front surface of the casing 83 so as to be arranged side by side, and the circulation pump 37 and the gutter pump 59 are attached to the rear surface of the casing 83 so as to be arranged side by side. Yes. The pump motor 84 is attached to the right side surface of the casing 83.

  The pump motor 84 is provided with one rotating shaft, and an eccentric cam 99 corresponding to each pump 37, 43, 48, 59 is attached to this rotating shaft (see FIGS. 15A to 15D). Accordingly, when the pump motor 84 is driven and the rotation shaft rotates, the eccentric cams 99 attached to the rotation shaft rotate, and the corresponding pumps 37, 43, and so on correspond to the rotation of the eccentric cam 99. 48 and 59 operate integrally. That is, each pump 37, 43, 48, 59 is driven by one pump motor 84 via a common rotating shaft.

  As shown in FIG. 4, the circulation pump 37 is connected to an ink circulation suction pipe 36a, which is the suction side of the ink circulation pipe 36, at the lower part thereof, and at the upper part, the ink circulation discharge, which is the discharge side of the ink circulation pipe 36 A tube 36b is connected. The gutter pump 59 is connected to the lower part thereof with an ink recovery / intake pipe 57a which is the suction side of the ink recovery pipe 57, and is connected to the upper part of the ink recovery / discharge pipe 57b which is the discharge side of the ink recovery pipe 57. Yes.

  The eight pipes on the suction side and the discharge side of the circulation pump 37, the replenisher pump 43, the ink pump 48, and the gutter pump 59 are all extended to the mounting plate 85 side. Connected to the connector. More specifically, the two pipes 36a and 36b on the suction side and the discharge side of the circulation pump 37 and the two pipes 57a and 57b on the suction side and the discharge side of the gutter pump 59 are connected to the upper tube connector. Has been. In addition, the two pipes 44 and 42 on the suction side and the discharge side of the replenisher pump 43 and the two pipes 47 and 49 on the suction side and the discharge side of the ink pump 48 are connected to the lower tube connector. ing.

In the example of FIG. 4, the configuration of a pump unit in which a plurality of pumps are integrated has been described. However, the present invention is not limited to this configuration, and it is needless to say that pumps can be provided individually. Absent.
(Gutter pump 59)

  A configuration example of the gutter pump 59 will be described based on the schematic diagrams of FIGS. 15A to 15D. The gutter pump 59 communicates with the suction side on the outside air side and the discharge side on the ink tank side (not shown). The gutter pump 59 includes a casing 91, a suction-side check valve 92 disposed on the liquid suction side, a discharge-side check valve 93 disposed on the liquid discharge side, and an adjustment valve 94. The suction-side check valve 92 is a check valve that allows the liquid to flow only in the direction of sucking the liquid to the pump side. On the contrary, the discharge side check valve 93 is a check valve for allowing the liquid to flow only in the direction of discharging the liquid from the pump side.

  The adjustment valve 94 adjusts the pressure in the casing 91 to perform a liquid suction operation into the pump and a liquid discharge operation outside the pump. The gutter pump 59 shown in this figure employs a diaphragm pump that uses a diaphragm as the adjusting valve 94 and changes the volume of the casing 91 by rotating the eccentric cam 99 to bend the diaphragm. Diaphragm pumps are gas-liquid mixing type and can take in both liquid and gas. That is, this pump conveys a mixture of ink and replenisher. The mixing ratio of the replenisher is adjusted by the ink viscosity. In addition, only the replenisher may be transported at the time of cleaning or starting up. Therefore, in the present specification, a liquid mixture including a replenisher and an ink mixture, only a replenisher, and only ink is expressed.

  The diaphragm separates the internal space from the external space, and as shown in FIGS. 15A to 15D, the pressure is adjusted by the eccentric cam rotation mechanism 98, thereby changing the internal pressure of the internal space of the diaphragm pump. The suction and discharge operations are performed. The eccentric cam rotating mechanism 98 is fixed to the rotating shaft of the pump motor 84 and is periodically driven to periodically deform the diaphragm 94A, and as shown in FIGS. The process is repeated continuously. Accordingly, the pump operation is continued so that the ink sucked from the suction port is ejected from the ejection port without backflow.

  As shown in FIG. 16A, this diaphragm type pump uses a ball type check valve as a check valve. The ball check valve includes a ball 1601 and its valve seat 1602. Here, a slight gap is formed between the ball 1601 and the valve seat 1602. If the liquid is transported by this pump, the presence of the gap is not a problem because the liquid fills the gap. However, when the gas is transported, the gas leaks from the gap, so that the transport capability is impaired and the flow rate is extremely reduced. In other words, once the liquid has been lost from the pump for some reason and dried, it becomes difficult to start the pump again. In this case, the liquid can be started by pouring the liquid in some way, such as “priming water”.

Here, in the gutter pump of the ink jet recording apparatus, the target to be sucked is a gas-liquid mixed fluid, and the liquid is relatively small. Also, if the ink jet recording apparatus is left unused for a long time, the liquid tends to dry, and the pump may not start. In particular, since the check valve on the suction side of the gutter pump is exposed to the outside air, the ink tends to dry.
(Recovery operation mode)

  Therefore, the ink jet recording apparatus according to the present embodiment has a recovery operation mode in which liquid is introduced into the pump and recovered when the pump is dried and cannot suck ink. Specifically, using an on-off valve connected to the pump flow path, the pump operation is performed by opening and closing the on-off valve instead of the check valve that has become inoperable. The liquid can be introduced into the pump, and the function of the pump can be restored by the action of the priming water. Examples of such pumps are shown in FIGS. 5A-5D. As shown in these drawings, a suction-side electromagnetic valve 95 is provided in advance on the suction side of the pump 90. As the suction side electromagnetic valve 95, the above-described electromagnetic valve V10 can be suitably used. That is, using the existing solenoid valve V10, it is possible to smoothly perform the recovery operation of the gutter pump without adding a new member. However, it is needless to say that the suction side electromagnetic valve 95 can be separately provided without being limited to this configuration. In this example, the on-off valve is an electromagnetic valve, but other types of valves capable of blocking and opening the flow path can be used in addition to the electromagnetic valve.

  Next, an operation procedure for performing suction and discharge of the pump 90 using the suction side electromagnetic valve 95 will be described with reference to FIGS. 5A to 5D. Here, of the check valves provided in the pump 90, only the suction-side check valve 92 has a gap as shown in FIG. 16B. In other words, the ink dries and hardens in a state where the valve cannot be completely closed. An example of recovering from a state that has been lost will be described. The discharge side check valve 93 is assumed to operate normally. Furthermore, in these drawings, the illustration of the eccentric cam is omitted in order to simplify the description.

  First, in the suction process shown in FIG. 5A, the pressure in the casing 91 is reduced to suck the liquid into the pump 90. For this reason, the control unit 30 operates the eccentric cam to start expansion of the adjustment valve 94. As a result, the pressure inside the casing 91 starts to decrease, and the suction force works due to the pressure difference due to the negative pressure state. As a result, the discharge side check valve 93 is closed. On the other hand, the control unit 30 opens the suction side electromagnetic valve 95 so as to synchronize with the expansion operation of the adjustment valve 94. As a result, liquid is sucked into the pump 90 through the suction-side electromagnetic valve 95. At this stage, it is not necessary for the liquid to be completely introduced into the casing 91 at once, and it is sufficient that a part of the liquid is drawn toward the casing 91 side. For example, the liquid level may approach the casing 91 side. Since the pump 90 is a gas-liquid mixed type, both gas and liquid can be sucked, and a part of the liquid or gas (here, air) is taken into the casing 91. In the present specification, for simplification of description, “liquid is sucked into the pump” is meant to include gas in “liquid”. Further, as the liquid to be sucked, a replenisher having a viscosity lower than that of ink is preferable. This is because a liquid having a low viscosity and fluidity is more easily sucked into the pump, and can be expected to return to a state in which the check valve can be operated by washing and eluting the hardened ink.

  Next, as shown in FIG. 5B, in the state where the regulating valve 94 is completely expanded, the suction side electromagnetic valve 95 is closed by the control unit 30, and the suction process is temporarily stopped.

  Further, as shown in FIG. 5C, the control unit 30 starts to contract the regulating valve 94 this time. As a result, the internal pressure in the pump 90 rises, the discharge side check valve 93 is pressed and opened, and the liquid (gas in the example of FIG. 5A) sucked earlier is discharged from the pump 90. On the other hand, since the suction-side check valve 92 is hardened in an open state that cannot be completely closed, liquid tends to leak to the suction side from the pump 90 through the suction-side check valve 92. Since the suction side solenoid valve 95 is closed, the suction side solenoid valve 95 prevents backflow. In particular, when the object of backflow is gas, the backflow is blocked by the presence of the gas present in the flow path from the closed suction side electromagnetic valve 95 to the suction side check valve 92.

  Then, as shown in FIG. 5D, when the regulating valve 94 is completely contracted, the pressing force is lost, so that the discharge side check valve 93 is closed.

Thereafter, the controller 30 controls the expansion / contraction of the regulating valve 94 and the opening / closing of the suction side electromagnetic valve 95 so as to repeat the operations of FIGS. 5A to 5D again. As a result, in place of the non-operating suction side check valve 92, the suction side check valve 92 is substantially closed by opening and closing with the suction side electromagnetic valve 95 connected to the suction side of the pump 90. The function can be achieved, and the liquid can be gradually introduced into the pump 90. Finally, when the pump 90 is filled with the liquid, the liquid can be introduced by the action of the priming water. Further, the suction side check valve 92 is washed by the liquid (replenisher) conveyed by the pump 90, and the solidified ink is gradually melted and finally washed away to fix the suction side check valve 92. If the operation is canceled and the pump operates normally, the operation of the pump 90 can be completely restored.
(Embodiment 2)

  In the first embodiment described above, the example in which the electromagnetic valve is connected to the suction side check valve 92 side of the pump 90 has been described. However, the present invention is not limited to this configuration, and the solenoid valve can also be connected to the discharge check valve side of the pump. With this configuration, not only the suction-side check valve but also the discharge-side check valve can be operated even when the discharge-side check valve becomes hard and does not operate.

  Such a configuration example is shown in FIGS. 6A to 6D as the second embodiment. In addition to the suction side solenoid valve 95B provided on the suction side path of the pump 90B, the pump 90B is provided with a discharge side solenoid valve 96B in communication with the discharge side check valve 93B on the discharge side path. ing. Similarly to the suction-side check valve 92B, the discharge-side solenoid valve 96B can be controlled to be opened and closed by the control unit 30. In these drawings, as in FIG. 5 and the like, the illustration of the eccentric cam that expands and contracts the diaphragm that is the regulating valve 94B is omitted.

  Hereinafter, in the pump 90B, when both the suction-side check valve 92B and the discharge-side check valve 93B are set in an open state and become inoperable, a procedure for recovering the operation by introducing liquid into the pump 90B will be described. This will be described with reference to FIGS. 6A to 6D. First, as shown in FIG. 6A, in the suction step of lowering the pressure in the casing 91B and sucking the liquid into the pump 90B, the controller 30 operates the eccentric cam to start expansion of the adjustment valve 94B. On the other hand, the suction side electromagnetic valve 95B is opened in synchronization with the expansion operation of the adjustment valve 94B. The discharge side solenoid valve 96B is in a closed state. Thereby, a suction force is generated by gradually bringing the inside of the casing 91B into a negative pressure state, and the liquid is sucked into the pump 90B through the suction-side electromagnetic valve 95B.

  Next, as shown in FIG. 6B, in the state where the regulating valve 94B is completely expanded, the suction side electromagnetic valve 95B is closed by the control unit 30, and the suction process is temporarily stopped.

  Further, as shown in FIG. 6C, the control unit 30 starts contraction of the regulating valve 94B. Further, the discharge side electromagnetic valve 96B is opened in synchronization with the contraction operation of the regulating valve 94B. The suction side electromagnetic valve 95B maintains the closed state. As a result, the internal pressure in the pump 90B starts to rise, and the liquid sucked earlier is discharged from the pump 90B through the discharge-side electromagnetic valve 96B. On the other hand, since the suction-side check valve 92B is hardened in an open state that cannot be completely closed, liquid tends to leak from the pump 90B to the suction side through the suction-side check valve 92B. Since the suction-side electromagnetic valve 95B is closed, backflow is prevented by the suction-side electromagnetic valve 95B.

  As shown in FIG. 6D, when the regulating valve 94B is completely contracted, the discharge-side electromagnetic valve 96B is closed and the discharge process is completed.

  Thereafter, the control unit 30 controls the expansion / contraction of the regulating valve 94B and the opening / closing of the suction-side solenoid valve 95B and the discharge-side solenoid valve 96B so as to repeat the operations in FIGS. 6A to 6D in the same manner. . Accordingly, the suction side check valve 92B and the discharge side check valve 93B are replaced by the suction side solenoid valve 95B and the discharge side solenoid valve 96B to perform the closing and opening operations, thereby substantially reducing the suction side check valve. The functions of the stop valve 92B and the discharge side check valve 93B can be achieved, and the liquid can be gradually introduced into the pump 90B. Finally, when the pump 90B is filled with the liquid, the liquid can be introduced by the action of the priming water as in the first embodiment.

In this configuration, the solenoid valve V11, V1, V3, V4, etc. shown in FIG. 3 can be used as the discharge side solenoid valve 96B connected to the discharge side check valve 93B. When using each solenoid valve, a gap is not generated from other than the solenoid valve operating in the flow path, such as closing other unused solenoid valves as necessary. In addition to selecting and using only one solenoid valve, a plurality of solenoid valves may be used in synchronization. With this method, a larger suction force or discharge force can be applied. Further, as in the first embodiment, a dedicated discharge-side solenoid valve may be separately provided.
(Embodiment 3)

  In the second embodiment described above, the example in which the electromagnetic valve is connected to both the suction side check valve 92B side and the discharge side check valve 93B of the pump 90B has been described. However, the present invention is not limited to this configuration, and the electromagnetic valve may be connected only to the discharge side check valve side of the pump. With this configuration, the recovery operation can be performed when the discharge-side check valve does not operate firmly and only the suction-side check valve operates normally.

  Such a configuration example will be described as a third embodiment with reference to FIGS. 7A to 7D. The pump 90C is provided with a discharge-side check valve 93C in communication with the discharge-side check valve 93C on the discharge-side path of the pump 90C. The discharge side check valve 93 </ b> C can be controlled to be opened and closed by the control unit 30. In these drawings, as in FIG. 5 and the like, the illustration of the eccentric cam for expanding and contracting the diaphragm which is the regulating valve 94C is omitted.

  Hereinafter, when the suction-side check valve 92C operates in the pump 90C, but the discharge-side check valve 93C is stuck in the open state and does not operate, the liquid is introduced into the pump 90C to restore the operation. A procedure is demonstrated based on FIG. 7A-FIG. 7D. First, as shown in FIG. 7A, in the suction step of lowering the pressure in the casing 91C and sucking the liquid into the pump 90C, the controller 30 operates the eccentric cam to start expansion of the adjustment valve 94C. On the other hand, the discharge side solenoid valve 96C is closed. Thus, a suction force is generated by gradually bringing the inside of the casing 91C into a negative pressure state, the suction-side check valve 92C is lifted and opened, and the liquid is sucked into the pump 90C.

  Next, as shown in FIG. 7B, in the state where the regulating valve 94C is completely expanded, the suction force is lost, the suction side check valve 92C is lowered and closed, and the suction process is temporarily stopped.

  Further, as shown in FIG. 7C, the control unit 30 starts the contraction of the regulating valve 94C. Further, the discharge side electromagnetic valve 96C is opened in synchronization with the contraction operation of the regulating valve 94C. As a result, the internal pressure in the pump 90C starts to rise, and the liquid sucked earlier is discharged from the pump 90C through the discharge-side electromagnetic valve 96C. On the other hand, since the suction side check valve 92C is closed, the back flow of the liquid is prevented.

  Then, as shown in FIG. 7D, when the regulating valve 94C is completely contracted, the discharge-side electromagnetic valve 96C is closed, and the discharge process ends.

  Thereafter, the controller 30 controls the expansion / contraction of the regulating valve 94C and the opening / closing of the discharge-side electromagnetic valve 96C so as to repeat the operations of FIGS. 7A to 7D in the same manner. Thus, the function of the discharge-side check valve 93C can be substantially achieved by performing the closing and opening operation with the discharge-side electromagnetic valve 96C instead of the non-operating discharge-side check valve 93C. The liquid can be gradually introduced into the pump 90C, and when the liquid finally fills the pump 90C, the liquid can be introduced by the action of the priming water as in the first embodiment.

Even in this configuration, the solenoid valve V11, V1, V3, V4, etc. shown in FIG. 3 can be used as in the second embodiment.
(Determining whether recovery operation is necessary)

  Further, the ink jet recording apparatus may be configured to accept an instruction for executing the recovery operation mode at an arbitrary timing from the outside as the timing of activating the recovery operation function. For example, it can be executed at a timing specified by the user. In this case, the user designates an instruction for executing the recovery operation mode from the operation display unit 8. For example, the operation display unit 8 provides a user interface that allows the user to execute the recovery operation mode as a maintenance operation when an abnormality occurs.

  Alternatively, the recovery operation mode can be executed at a predetermined timing. For example, it can be performed when the ink jet recording apparatus is activated or every predetermined number of days. Specifically, every time the inkjet recording device is started, the control unit checks whether or not a recovery operation is necessary, and automatically when a certain period of time has passed since the previous use of the inkjet recording device. Alternatively, the recovery operation mode may be set to be executed.

Regardless of whether or not an abnormality has occurred, in addition to the method of uniformly executing the recovery operation mode after a lapse of a certain period of time, such an abnormality is detected by actually detecting whether or not ink has been dried in each pump. May be detected to prompt the user to execute the recovery operation mode, or to automatically execute the recovery operation mode. Therefore, the control unit can include a timer that defines the timing for executing the recovery operation mode.
(Control unit 30)

  A connection example of the control unit 30 is shown in the block diagram of FIG. As shown in this figure, the control unit 30 is connected to the operation display unit 8 that is an input unit, the personal computer 15 that is a display unit, the head unit 6, the electromagnetic valve 97, the pump motor 84, and the like. Exchange. The control unit 30 is also connected to the memory unit 110, the timing defining unit 120, and the pump volume change detecting unit 124.

  The memory unit 110 holds necessary data such as settings of the ink jet recording apparatus, and includes a nonvolatile memory 111 and a volatile memory 112. The control unit 30 accesses the memory unit 110 as necessary, reads necessary information, and writes necessary information.

  The timing defining unit 120 defines the timing for causing the control unit 30 to execute the recovery operation mode. For example, a timer IC or a calendar IC can be used as the timing defining unit 120.

  The pump volume change detecting means 124 is a means for detecting a pump volume change. For example, as shown in FIGS. 15A to 15D, in an eccentric cam rotation mechanism 98 that presses a diaphragm, which is an adjustment valve, with an eccentric cam 99, cam rotation that detects a rotation angle of the eccentric cam 99 that is rotated by a pump motor 84. The angle detection means can be used as the pump volume change detection means 124. The control unit 30 grasps the volume change of the pump with a signal from the pump volume change detecting means 124. When the pump volume change detecting means 124 is a cam rotation angle detecting means, the state of the adjusting valve, that is, the volume of the pump is grasped by the rotation angle of the eccentric cam 99. The pump volume change detecting means 124 for the controller to grasp the pump volume is not limited to the cam rotation angle detecting means, but a proximity sensor, a photoelectric sensor or the like can be used instead of or in addition to the cam rotation angle detecting means. It is also possible to detect the expansion / contraction degree of the regulating valve. Alternatively, the state of the eccentric cam can be detected by measuring the current load of the pump motor. Or it is good also as a structure which detects the rotation position of an eccentric cam based on the control signal of a pump motor.

  Next, timing when the control unit 30 controls the adjustment valve and the electromagnetic valve will be described. Here, the control in the example shown to FIG. 5A-FIG. 5D is demonstrated based on FIG. FIG. 9 is a graph showing the change over time of the volume in the casing of the pump. As shown by the broken line in FIG. 9, the control unit is configured such that the eccentric cam rotates and the suction side electromagnetic valve 95 is opened during the period when the pump volume is in the expansion period and closed during the other periods. Control with 30. For this reason, the control unit 30 controls the opening and closing of the suction side electromagnetic valve 95 in synchronization with this while detecting the rotation angle of the eccentric cam by the pump volume change detecting means 124 described above. In addition, the length of the valve opening period, the timing of valve opening and closing (the phase of the volume change waveform in FIG. 9), etc. are finely adjusted while taking into account factors such as gas response delay. Here, based on the detection result of the pump volume change detecting means 124, the control unit 30 opens the suction side electromagnetic valve 95 for a certain period from a phase where the volume changes.

  In the second embodiment shown in FIGS. 6A to 6D, the control unit 30 also controls the opening and closing of the discharge side electromagnetic valve 96B in addition to the suction side electromagnetic valve 95B. An example of this control is shown in FIG. Here, as in FIG. 9, the suction side electromagnetic valve 95B is opened during the period when the eccentric cam rotates and the pump volume is in the expansion period as shown by the broken line, and is closed during the other periods. The control unit 30 controls the opposite sex. On the other hand, for the discharge side solenoid valve 96B, as indicated by the alternate long and short dash line, the control unit 30 opens the discharge side solenoid valve 96B during the period when the pump volume is in the contraction period and closes the valve during the other periods. Control. Similarly, in the example of the third embodiment shown in FIGS. 7A to 7D, the opening and closing of the discharge-side electromagnetic valve 96C can be controlled at the timing indicated by the one-dot chain line in FIG.

  The electromagnetic valve can be opened and closed, for example, by instructing only the valve opening timing by the control unit 30 and the valve closing timing can be automatically closed after a predetermined period. In this case, the solenoid valve is automatically closed at a predetermined time after being opened according to a timer or the like. Such an example will be described based on the flowchart of FIG. 11 in the case of the second embodiment. First, in step S111, the control unit 30 performs a process of detecting a phase from a change in pump capacity based on the detection result of the pump capacity change detection means. Next, in step S112, it is determined whether or not the adjustment valve is in the expansion period. If the adjustment valve is in the expansion period, the process proceeds to step S113, and processing for opening the suction side electromagnetic valve 95B is started. On the other hand, if it is not the diastole, it is determined in step S114 whether or not it is in the systole. In the case of the systole, the process proceeds to step S115, and a process for opening the discharge-side electromagnetic valve 96B is started. If it is not the systole, the process returns to step S111 and the following processing is repeated.

  On the other hand, the procedure for opening / closing the suction side electromagnetic valve 95B will be described based on the flowchart of FIG. First, in step S121, a valve opening process command for the suction side electromagnetic valve 95B is received in step S113 of the flowchart of FIG. 11, and the valve opening process is started. In step S122, the suction side electromagnetic valve 95B is opened. In step S123, counting of the suction side solenoid valve opening time timer is started and waited until counting up. In step S124, when the time set by the timer has elapsed, the suction side electromagnetic valve 95B is closed. Regarding the timer, in addition to arranging such a timer on the suction side electromagnetic valve 95B, the control unit communicates with the timer, and after the count up, a valve closing command is sent to the suction side electromagnetic valve 95B. Also good.

  The same procedure can be used for the discharge-side solenoid valve 96B. Hereinafter, the description will be made based on the flowchart of FIG. 13. First, in step S131, the valve opening process command is started in response to the valve opening process command of the discharge side electromagnetic valve 96B in step S114 of the flowchart of FIG. The side solenoid valve 96B is opened. In step S133, counting of the discharge side solenoid valve 96B valve opening time timer is started and waited until counting up. In step S134, when the time set by the timer has elapsed, the discharge-side electromagnetic valve 96B is closed.

  The above describes the procedure in which the control unit 30 controls the opening and closing of the suction side solenoid valve 95B and the discharge side solenoid valve 96B in the example of the second embodiment, but the control unit similarly applies to the first and third embodiments. 30 can control the opening and closing of each solenoid valve.

  As described above, the suction side solenoid valve and the discharge side solenoid valve are controlled by the control unit so that the opening and closing operations of the on-off valve coincide with the operation timing of the suction side check valve or the discharge side check valve of the pump. By controlling the opening and closing of the liquid, it is possible to efficiently suck and discharge liquids such as ink and replenisher. However, the operation of the suction side solenoid valve and the discharge side solenoid valve outside the pump does not necessarily need to be controlled to coincide with the operation timing of the pump side suction side check valve and discharge side check valve. For example, by opening the solenoid valve repeatedly at regular intervals, or by randomly opening and closing the valve, the timing that coincides with the opening and closing of the suction-side check valve and discharge-side check valve is randomly selected. It is also possible to produce priming action. However, in this method, opening and closing of the electromagnetic valve must be repeated unnecessarily many times, and in terms of efficiency and durability, it is inferior to the method of measuring the timing described above. For this reason, an appropriate opening / closing timing of the solenoid valve is defined according to required accuracy, durability, cost, and the like.

  The above pump 90, 90B, 90C demonstrated the example applied to the gutter pump 59. FIG. Since the suction side faces the outside air, the gutter pump is likely to dry the suction side check valve. Therefore, the gutter pump can be stably used by providing such a recovery operation mode. However, it goes without saying that the present invention can be applied to other pumps.

  In the above example, an example of a diaphragm type pump has been described. However, the present invention is not limited to this. For example, the volume of the cylinder chamber is increased by rotating a pump eccentric cam to reciprocate a piston in a predetermined reciprocating direction. The present invention can also be applied to other passive pumps such as a reciprocating pump unit to be changed and a poppet pump.

  As described above, according to the present embodiment, it is possible to substitute the functions of the suction-side check valve and the discharge-side check valve using one or more solenoid valves, and these check valves operate. Even when it becomes impossible, the inkjet recording apparatus can be restored. In addition, the electromagnetic valve V10 for opening the flow path when the ink jet recording apparatus is operating and closing the flow path when the ink jet recording apparatus is not operating is used as the suction side electromagnetic valve, so that the existing electromagnetic valve included in the ink jet recording apparatus is used. Thus, it can be used as an electromagnetic valve for the pump recovery operation, and the pump recovery function can be realized at a low cost and with a simplified configuration.

  When the gutter pump 59 is used as the pumps 90, 90B, and 90C, the pump can be recovered by supplying liquid from the gutter and operating the regulating valve. For example, a liquid such as a replenisher or water is poured from the gutter into the flow path. For example, a water droplet is dropped near the entrance of the gutter. When the regulator valve is operated in this state and the recovery operation is performed, the negative pressure generated by the pump causes the liquid to move gradually from the gutter toward the pump, and finally the liquid is supplied into the pump and dried. The ink can be dissolved with a liquid to restore the pump. With this method, liquid can be introduced into the pump and recovered without using an electromagnetic valve.

  An inkjet recording apparatus and an inkjet recording apparatus recovery method according to the present invention include, for example, an industrial continuous inkjet printer, particularly an apparatus for recovering an ink when the gutter pump is dried and the gutter pump does not operate. It can be suitably used as a method.

DESCRIPTION OF SYMBOLS 100 ... Inkjet recording apparatus 2 ... Belt conveyor 3 ... Object 4 ... Inkjet recording apparatus main body 5 ... Flexible hose 6 ... Head part 7 ... Wiring cable 8 ... Operation display part 9 ... Main body housing 13 ... Speed detection sensor 14 ... Passing Detection sensor 15 ... personal computer 16 ... programmable controller 17 ... rotating lamp 18 ... buzzer 22 ... pressurizer 23 ... nozzle 24 ... charging electrode; 24a, 24b ... electrode plate 25 ... charging detection sensor 26 ... deflection electrode; 26a ... electrode plate; 26b ... Electrode plate 27 ... Gutter 28 ... Ejection port 29 ... High-voltage power supply line 30 ... Control unit 31 ... Ink tank 32 ... Replenisher tank 33 ... Main tank 34 ... Conditioning tank 35 ... Exhaust pipe 36 ... Ink circulation pipe; 36a ... Ink Circulation suction pipe; 36b ... Ink circulation discharge pipe 37 ... Circulation pump 38 ... Circulation fill 39 ... Viscometer 40 ... Ink inflow pipe 41 ... Ink tank filter 42 ... Replenisher inflow pipe 43 ... Replenisher liquid pump 44 ... Replenisher liquid supply pipe 45 ... Replenisher liquid tank filter 46 ... Replenisher main filter 47 ... Ink supply pipe 48 ... Ink pump 49 ... Ink delivery pipe 50 ... Pressure reducing valve 51 ... Pressure gauge 52 ... Ink main filter 53 ... Pre-ejection ink filter 54 ... Replenishing liquid delivery pipe 55 ... Pressure reducing valve 56 ... Pre-ejection replenishing liquid filter 57 ... Ink recovery pipe; 57a Ink recovery / intake pipe 57b Ink recovery / discharge pipe 58 Gutter filter 59 Gutter pump 60 Recovery replenisher supply pipe 61 Recovery replenisher inflow pipe 62 Drain pipe 63 Connection pipe 64 Ink return pipe 65 Ink Sub-filter 66 ... Air flow pipe 73 ... Booster circuit 80 ... Pump unit 83 ... Casing 84 ... Pump motor 85 ... Mounting plate 9 , 90B, 90C ... pumps 91, 91B, 91C ... casings 92, 92B, 92C ... suction side check valves 93, 93B, 93C ... discharge side check valves 94, 94B, 94C ... regulating valves; 94A ... diaphragms 95, 95B ... Suction side solenoid valve 96, 96B, 96C ... Discharge side solenoid valve 97 ... Solenoid valve 98 ... Eccentric cam rotation mechanism 99 ... Eccentric cam 110 ... Memory unit 111 ... Non-volatile memory 112 ... Volatile memory 120 ... Timing defining unit 124 ... Pump volume change detecting means 1401 ... nozzle portion 1402 ... ink ejection hole 1403 ... liquid supply pipe 1404 ... piezoelectric vibrator 1405 ... outlet 1406 ... head 1420 ... ejection nozzle 1424 ... charging electrode 1425 ... housing 1426 ... deflection electrode 1427 ... gutter 1433 ... return path 1444 ... solvent supply pipe 1447 ... ink supply pipe 14 57 ... first recovery pipe 1601 ... ball 1602 ... valve seat 1794 ... diaphragm 1795 ... suction side check valve 1796 ... discharge side check valve V1 ... recovered ink supply switching valve V2 ... ink return switching valve V3 ... recovery replenisher supply switching Valve V4 ... Drainage switching valve V5 ... Circulation supply switching valve V6 ... Air flow switching valve V8 ... Ink inflow switching valve V9 ... Recovery replenisher inflow switching valve V10 ... Gutter inflow switching valve V11 ... Circulation delivery switching valve V12 ... Replenishment liquid delivery Switching valve V13 ... Replenisher inflow switching valve V14 ... Injection switching valve A ... Print object GP ... Gap

Claims (14)

A continuous ink jet recording apparatus that causes ink to fly and adhere to a recording object, and collects unused ink.
An ink tank for storing ink;
A pump for transporting the ink or a liquid containing a replenisher for diluting the ink;
The pump is
A casing,
A suction-side check valve that is arranged on the suction side of the liquid to be transported of the casing and for flowing the liquid only in the direction of sucking the liquid;
A discharge-side check valve arranged on the liquid discharge side of the casing for flowing the liquid only in the direction of discharging the liquid;
An adjustment valve for adjusting the pressure in the casing and performing a liquid suction operation into the pump and a liquid discharge operation outside the pump;
The inkjet recording apparatus further includes
An on-off valve connected to the liquid suction side or the liquid discharge side of the casing via the flow path and capable of blocking the flow path;
A control unit for controlling the adjustment valve and the on-off valve;
The controller is configured to discharge the liquid to the outside of the pump by the operation of blocking the flow path with the on-off valve when at least one of the suction side check valve or the discharge side check valve does not operate normally. The inkjet recording apparatus is configured so that a recovery operation mode for controlling the regulating valve and the on-off valve can be executed. The inkjet recording apparatus according to claim 1,
The control unit controls the operation of the on-off valve and the regulating valve so that the opening and closing operations of the on-off valve coincide with the operation timing of the suction side check valve or the discharge side check valve of the pump. An ink jet recording apparatus comprising: The inkjet recording apparatus according to claim 1 or 2,
The on-off valve is connected to the suction-side check valve;
The control unit is
Expanding the regulating valve, closing the discharge-side check valve, and opening the on-off valve to reduce the pressure in the casing and suck the liquid into the pump;
With the adjustment valve expanded, the on-off valve is closed,
Contracting the regulating valve, opening the discharge-side check valve, and discharging liquid from the pump;
A method for restoring an ink jet recording apparatus, comprising: sequentially controlling an operation of closing the discharge-side check valve while the adjustment valve is contracted. The inkjet recording apparatus according to claim 1 or 2,
The on-off valve is connected to the discharge-side check valve;
The control unit is
By expanding the adjustment valve, opening the suction side check valve, and closing the open / close valve,
Reducing the pressure in the casing to suck liquid into the pump;
With the adjustment valve expanded, the suction side check valve is closed while the on-off valve is closed,
Contracting the regulating valve, opening the on-off valve, and discharging liquid from the pump;
A method for restoring an ink jet recording apparatus, comprising: sequentially controlling an operation of closing the on-off valve while the adjustment valve is contracted. The inkjet recording apparatus according to any one of claims 1 to 4,
An ink jet recording apparatus, wherein the on-off valve is provided on each of a liquid suction side and a liquid discharge side of the casing. An inkjet recording apparatus according to any one of claims 1 to 5,
The inkjet recording apparatus, wherein the control unit controls to execute the recovery operation mode at a predetermined timing set in advance. The inkjet recording apparatus according to any one of claims 1 to 6,
An ink jet recording apparatus, wherein the control unit is configured to receive an instruction for executing a recovery operation mode at an arbitrary timing from the outside. An inkjet recording apparatus according to any one of claims 1 to 7,
An ink jet recording apparatus, wherein the pump is a gutter pump. The ink jet recording apparatus according to claim 1,
An ink jet recording apparatus, wherein the adjustment valve is a diaphragm. An ink jet recording apparatus according to any one of claims 1 to 9,
An ink jet recording apparatus, wherein the on-off valve is an electromagnetic valve. The inkjet recording apparatus according to claim 10,
An ink jet recording apparatus, wherein the electromagnetic valve is also used as an electromagnetic valve for opening the flow path when the ink jet recording apparatus is in operation and closing the flow path when the ink jet recording apparatus is not operating. An ink jet recording apparatus according to any one of claims 1 to 10,
An ink jet recording apparatus, wherein the ink tank is connected to a discharge side of the pump. When a pump for transporting the ink or a replenisher for diluting the ink does not operate in a continuous ink jet recording apparatus that causes ink to fly and adhere to a recording target and collect unused ink And a recovery method for recovering the operation of the pump,
The adjustment valve of the pump is expanded and the discharge side check valve for flowing the liquid only in the direction of discharging the liquid is closed on the liquid discharge side of the pump, and the pump Opening the on-off valve connected to the liquid suction side and sucking the liquid into the pump; and
Closing the on-off valve with the regulating valve expanded; and
With the on-off valve closed, the adjusting valve is contracted and the discharge-side check valve is opened to discharge liquid from the pump;
A method for recovering an ink jet recording apparatus, comprising: sequentially repeating a step of closing the discharge-side check valve while the adjustment valve is contracted. When a pump for transporting the ink or a replenisher for diluting the ink does not operate in a continuous ink jet recording apparatus that causes ink to fly and adhere to a recording target and collect unused ink And a recovery method for recovering the operation of the pump,
Expanding the adjustment valve of the pump and being disposed on the liquid suction side of the pump, opening a suction-side check valve for flowing the liquid only in the direction of sucking the liquid, and further, Closing the on-off valve connected to the liquid discharge side and sucking the liquid into the pump;
A step of closing the suction side check valve while closing the on-off valve in a state where the adjustment valve is expanded; and
With the suction-side check valve closed, the adjusting valve is contracted and the on-off valve is opened to discharge liquid from the pump;
A method for restoring an ink jet recording apparatus, comprising: sequentially repeating a step of closing the on-off valve in a state where the adjusting valve is contracted.

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