JP2011203204A - Apparatus and method for confirming operation of latch type solenoid valve, and ink jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect such a failure that a state cannot be maintained after finish of excitation in a latch type solenoid valve.SOLUTION: An apparatus for confirming operation of the latch type solenoid valve 10 for maintaining the state after being shifted after current supply stop, which is a latch type solenoid valve 10 that is shifted from a closed valve state into an open valve state by supplying a current into a coil 24 in a first direction, and that is shifted from the open valve state into the closed valve state by supplying a current in a second direction which is a reverse direction to the first direction, includes a valve driver for shifting the state of the latch type solenoid valve 10 by supplying a current in the first direction or in the second direction by a driving circuit, an inspection driver for supplying a current in the same direction as the valve driver by the driving circuit, a detector for detecting a driving current or a driving voltage of the driving circuit based on inspection driving, and a determiner for determining the operation state of the latch type solenoid valve 10 based on the driving current or the driving voltage detected by the detector.

Description

  The present invention relates to an operation confirmation apparatus and method for a latch-type electromagnetic valve, and an ink jet recording apparatus, and more particularly to a technique for detecting a failure in a latch-type electromagnetic valve that cannot maintain a state after excitation.

  When driving an electromagnetic valve, it is known that a waveform distortion occurs in a drive current waveform due to a counter electromotive force. By observing this waveform distortion, abnormal operation of the electromagnetic valve is detected and the driving time is optimized.

  For example, in Patent Document 1, the operation of the solenoid valve is confirmed by detecting the current when the power supply current is supplied to the solenoid valve.

  Moreover, in patent document 2, the operation | movement of the plunger in a solenoid is monitored by detecting the voltage change of the both ends of a varistor with respect to the drive signal applied to the solenoid.

  Moreover, in patent document 3, the current integral value and average value of the rise at the time of electromagnetic valve drive are extracted as feature values, and the presence or absence of a failure of the electromagnetic valve is determined by comparing with the feature value during normal operation. .

Japanese Unexamined Patent Publication No. 63-43081 JP-A-6-333732 Japanese Patent No. 4135494

  In order to reduce power consumption, a latch-type electromagnetic valve configured to use a permanent magnet and maintain the state even when energization is stopped after an opening / closing operation is known. FIG. 9 is a diagram showing an internal configuration of the latch type electromagnetic valve.

  FIG. 9A shows the closed state of the electromagnetic valve 10. In this state, the plunger 22 is brought into contact with the valve seat 26 via the diaphragm 30 by the biasing force of the spring 34, the orifice portion 28 in the valve seat 26 is closed, and the flow path 32 is closed. ing.

  When switching from the valve-closed state to the valve-opened state, the coil 24 is energized so that the magnetic flux is generated in the same direction as the magnetic flux of the core 20 formed of a permanent magnet, and the magnetic flux is generated in the coil 24. The plunger 22 is magnetized by this magnetic flux, and the plunger 22 exceeds the urging force of the spring 34 by the mutual attractive force, and is attracted to the core 20 side. In this state, the spring 34 provided between the core 20 and the plunger 22 is compressed. However, since the attracting force by the permanent magnet is stronger than the urging force of the spring 34, the energization to the coil 24 is stopped thereafter. The plunger 22 can maintain the valve open state without leaving the core 20.

  FIG. 9B shows the open state of the electromagnetic valve 10. In this state, the diaphragm 30 is separated from the valve seat 26, the orifice portion 28 in the valve seat 26 is opened, and the flow path 32 is opened.

  When the valve opening state is changed to the valve closing state again, the coil 24 is energized in the direction opposite to that at the time of valve opening, and the magnetic flux is generated by the coil 24 in the direction opposite to the magnetic flux of the permanent magnet of the core 20. The magnetic force of the permanent magnet is canceled by this magnetic flux, and the plunger 22 is separated from the core 20 by the biasing force of the spring 34. Even when energization of the coil 24 is stopped in this state, the plunger 20 is not attracted to the core 20 against the biasing force of the spring 34 because the core 20 and the plunger 22 are separated from each other. The valve closed state can be maintained.

  Such a latch-type solenoid valve operates normally when the coil is energized (during excitation) due to functional failure due to foreign matter sticking, etc., but maintains the valve open state or valve closed state after excitation is completed. In some cases, a failure may occur and the state may return to the state before excitation.

  However, in the techniques of Patent Documents 1 to 3, it has not been possible to detect the occurrence of the above-described malfunction of the latch-type electromagnetic valve.

  The present invention has been made in view of such circumstances, and provides an operation confirmation device and method for a latching electromagnetic valve, and an ink jet recording apparatus for detecting a failure in which a state cannot be maintained after the excitation of the latching electromagnetic valve is completed. Objective.

  In order to achieve the above object, an operation check device for a latch type electromagnetic valve according to claim 1, wherein a current is supplied to the coil in a first direction to shift from a valve closing state to a valve opening state. A latch-type electromagnetic valve that shifts from a valve-opened state to a valve-closed state by supplying a current in a second direction that is opposite to the direction of 1, and maintains the state after the transition after the current supply is stopped In the operation check device of the latch type electromagnetic valve, a valve drive means for supplying a current in the first direction or the second direction by a drive circuit to shift the state of the latch type electromagnetic valve, and the valve by the drive circuit Inspection driving means for supplying current in the same direction as the driving means; detection means for detecting a driving current or driving voltage of the driving circuit based on the inspection driving; and a driving current detected by the detection means or Based on the dynamic voltage, characterized in that a determination means for determining the operating state of the latching solenoid valve.

  According to the first aspect of the present invention, current is supplied to shift the state of the latch-type electromagnetic valve, current is supplied in the same direction to perform inspection driving, and driving current or driving of the driving circuit based on inspection driving is performed. Since the voltage is detected and the operation state of the latch type electromagnetic valve is determined based on the detected drive current or drive voltage, it is possible to detect a problem that the state cannot be maintained after the excitation of the latch type electromagnetic valve.

  According to a second aspect of the present invention, in the latch type electromagnetic valve operation confirmation device according to the first aspect, the apparatus further comprises a second detection unit that detects a drive current or a drive voltage of the drive circuit based on the valve drive, and the determination is performed. The means determines the operating state of the latch type electromagnetic valve based on the drive current or drive voltage detected by the second detection means.

  Thereby, the operation state of the latch type electromagnetic valve can be determined more appropriately.

  In order to achieve the above object, the operation check device for a latch type electromagnetic valve according to claim 3 is changed from a valve closed state to a valve open state when a current is supplied to the coil in a first direction. A latch-type electromagnetic valve that shifts from a valve-opened state to a valve-closed state by supplying a current in a second direction that is opposite to the direction of 1, and maintains the state after the transition after the current supply is stopped In the operation check device for a latch type electromagnetic valve, a current is supplied to each of the plurality of latch type electromagnetic valves by the respective drive circuits in the first direction or the second direction to shift the state of the latch type electromagnetic valve. Valve driving means, inspection driving means for sequentially supplying current in the same direction as the valve driving means to the plurality of latched electromagnetic valves by the respective driving circuits, and the inspection driving based on the inspection driving A single detecting means for sequentially detecting a driving current or a driving voltage of the moving circuit, and a determining means for determining individual operating states of the plurality of latch type electromagnetic valves based on the driving current or the driving voltage detected by the detecting means; It is characterized by comprising.

  According to the third aspect of the present invention, current is supplied to shift the states of the plurality of latch-type electromagnetic valves, and current is sequentially supplied in the same direction for inspection driving, and current of the driving circuit based on inspection driving is supplied. Or, the voltage is detected, and the operation state of the plurality of latching solenoid valves is determined based on the detected current or voltage, so that the state cannot be maintained after the excitation is completed from among the plurality of latching solenoid valves. An electromagnetic valve can be detected.

  4. The operation check device for a latch type electromagnetic valve according to claim 1, wherein the current supply time of the inspection drive means is shorter than the current supply time of the valve drive means. It is characterized by.

  Thereby, the inspection time can be shortened, and the power consumption required for the inspection can be reduced.

  In the latch type electromagnetic valve operation check device according to any one of claims 1 to 4, when the determination means determines that the operating state of the latch type electromagnetic valve is abnormal, It is characterized by comprising valve redrive means for supplying a current in the same direction as the valve drive means to shift the state of the latch type electromagnetic valve again.

  Thereby, the cause of the abnormality of the latch type electromagnetic valve can be removed and the normal state can be restored.

  According to a sixth aspect of the present invention, in the apparatus for confirming the operation of the latch type electromagnetic valve according to the fifth aspect, the valve re-driving unit supplies a current with a waveform different from that of the valve driving unit.

  Thereby, the cause of the abnormality of the latch type electromagnetic valve can be removed and the normal state can be restored.

  In the latch type electromagnetic valve operation check device according to any one of claims 1 to 4, when the operation state of the latch type electromagnetic valve is determined to be abnormal by the determination means, It is characterized by comprising valve reverse drive means for supplying a current in a direction opposite to the valve drive means to shift the state of the latch type electromagnetic valve.

  Thereby, the cause of the abnormality of the latch type electromagnetic valve can be removed and the normal state can be restored.

  In order to achieve the above object, an inkjet recording apparatus according to claim 8, wherein an inkjet head that ejects ink, an ink flow path that supplies the ink from an ink tank that stores the ink to the inkjet head, and the ink A latch-type electromagnetic valve for opening and closing the flow path and an operation confirmation device for the latch-type electromagnetic valve according to any one of claims 1 to 7 are provided.

  Thereby, the operating state of the latch type electromagnetic valve for opening and closing the ink flow path can be confirmed, and the recording quality of the ink jet recording apparatus can be maintained.

  In order to achieve the above object, according to a ninth aspect of the present invention, there is provided a method for confirming an operation of a latching electromagnetic valve, wherein a current is supplied to a coil in a first direction to shift from a valve closing state to a valve opening state. A latch-type electromagnetic valve that shifts from a valve-opened state to a valve-closed state by supplying a current in a second direction that is opposite to the direction of 1, and maintains the state after the transition after the current supply is stopped In the method for confirming the operation of the latching electromagnetic valve, a valve driving step of changing the state of the latching electromagnetic valve by supplying a current in the first direction or the second direction by a driving circuit, and the valve by the driving circuit An inspection driving step for supplying current in the same direction as the driving step, a detection step for detecting a driving current or a driving voltage of the driving circuit based on the inspection driving, and a driving current detected by the detection step or Based on the dynamic voltage, characterized in that a determination step of determining an operating state of the latching solenoid valve.

  In order to achieve the above object, the method for confirming the operation of the latch type electromagnetic valve according to claim 10, wherein a current is supplied to the coil in a first direction to shift from a valve-closed state to a valve-open state. A latch-type electromagnetic valve that shifts from a valve-opened state to a valve-closed state by supplying a current in a second direction that is opposite to the direction of 1, and maintains the state after the transition after the current supply is stopped In the operation check method of the latch type electromagnetic valve, a current is supplied to each of the plurality of latch type electromagnetic valves by the respective drive circuits in the first direction or the second direction to shift the state of the latch type electromagnetic valve. A valve driving step, an inspection driving step for supplying current to the plurality of latched electromagnetic valves in the same direction as the valve driving step by the respective driving circuits, and A detection step of sequentially detecting the drive current or drive voltage of the drive circuit by a single detection means, and determining the individual operating states of the plurality of latch type electromagnetic valves based on the drive current or drive voltage detected by the detection step And a determining step.

  According to the present invention, it is possible to detect a problem that the state cannot be maintained after the end of excitation in the latch type electromagnetic valve. Further, it is possible to detect an electromagnetic valve having a problem that the state cannot be maintained after the excitation is completed, from among a plurality of latched electromagnetic valves.

Schematic configuration diagram of operation check device for latch type solenoid valve Diagram for explaining current distortion during operation of electromagnetic valve Diagram showing valve drive pulse and valve inspection pulse Schematic block diagram of the operation check device of the second embodiment The figure which shows the valve drive pulse and valve inspection pulse of 2nd Embodiment Schematic configuration diagram of operation check device of other embodiment The figure which shows the valve drive pulse and valve inspection pulse of 3rd Embodiment Schematic showing a configuration example of an ink supply system of an ink jet recording apparatus equipped with an operation check device Diagram showing the internal configuration of a latching solenoid valve

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[Configuration of drive circuit]
FIG. 1 is a schematic configuration diagram of an operation confirmation device for a latch type electromagnetic valve to which the present invention is applied.

  As shown in the figure, the operation check device 40 of the present embodiment includes a control circuit 50, a current detection circuit 52, a current detection resistor 54, a valve drive driver 58, and the like, and is connected to the valve drive driver 58. The operation of the electromagnetic valve 10 is confirmed.

  The electromagnetic valve 10 is a latching electromagnetic valve shown in FIG. 9, and when the coil 24 is energized, the valve open / close state is switched.

  The control circuit 50 is constituted by a CPU, and controls each part of the operation check device 40 by reading a control program recorded in a ROM (not shown) and sequentially executing the program.

  The current detection circuit 52 is a circuit that detects the current flowing through the current detection resistor 54 by detecting the voltage across the current detection resistor 54.

  The current detection resistor 54 is a resistor connected in series with the power source of the valve drive driver 58, and generates a voltage corresponding to the current flowing through the valve drive driver 58 at both ends thereof.

  The valve drive driver 58 is a driver for driving the electromagnetic valve 10, and applies a voltage across the coil 24 of the electromagnetic valve 10 based on a control signal from the control circuit 50.

  When the valve drive driver 58 applies a voltage across the coil 24 of the electromagnetic valve 10, a current flows through the coil 24, and a magnetic flux is generated according to the direction of the current. The valve closing state is switched.

  The current flowing through the coil 24 also flows through the current detection resistor 54, and a voltage corresponding to the current value is generated at both ends of the current detection resistor 54. By detecting this voltage value, the current detection circuit 52 measures the drive current of the electromagnetic valve 10.

[Drive waveform and current waveform]
2A shows the voltage applied to the coil 24 when the electromagnetic valve 10 is shifted from the closed state to the open state, and FIG. 2B shows that the voltage shown in FIG. 2A is applied. It is a waveform (detection result of the current detection circuit 52) of the electric current which flows into the coil 24 when the plunger 22 moves and it transfers to a valve opening state from a valve closing state.

  As shown in FIG. 2B, when the voltage of FIG. 2A is applied, the plunger 22 moves inside the coil 24, so that back electromotive force is generated in the coil 24 and current distortion occurs. (Partial waveform C1).

  2C shows the waveform of the current flowing through the coil 24 when the voltage shown in FIG. 2A is applied to the coil 24 again in the opened electromagnetic valve 10 (the detection result of the current detection circuit 52). ).

  In this case, the plunger 22 is already attracted to the core 20 side, and the plunger 22 does not move even when the voltage shown in FIG. Therefore, no back electromotive force is generated in the coil 24 and no current distortion occurs (partial waveform C2).

  As described above, when the operation of the electromagnetic valve 10 is normal, when a voltage is continuously applied to the coil 24 in the same direction, the current waveform is different between the first time when the plunger 22 moves and the second time when the plunger 22 does not move.

  Although the valve open state has been described here, the same applies when a voltage is applied to the coil 24 so that the magnetic flux is generated in the direction in which the plunger 22 moves away from the core 20 in the valve closed state. In the present embodiment, the state of the latch-type electromagnetic valve is checked using this principle.

[First Embodiment]
FIG. 3A is a diagram showing a valve driving pulse 301 and a valve inspection pulse 302 applied from the valve driving driver 58 to the coil 24 of the electromagnetic valve 10. The valve driving pulse 301 is assumed to be a pulse for shifting from the valve closing state to the valve opening state.

  3B and 3C show detection results of the current detection circuit 52 when the pulse shown in FIG. 3A is applied.

  The valve drive driver 58 first applies a valve drive pulse 301 to the coil 24 of the electromagnetic valve 10 and applies a valve inspection pulse 302 after a predetermined time has elapsed.

  As shown in FIG. 3B, the current detection circuit 52 detects a current waveform 311 in the vicinity of the rising edge of the valve drive pulse 301. If the plunger 22 is operating normally, as shown in FIG. 3B, the current waveform 311 becomes a waveform having a distortion like the partial waveform C1 of FIG.

  Further, the current detection circuit 52 detects the current waveform 312 near the rising edge of the valve inspection pulse 302. If the plunger 22 is operating normally, the current waveform 312 is a distortion-free waveform such as the partial waveform C2 of FIG. 2 as shown in FIG.

  The control circuit 50 determines whether the operation of the electromagnetic valve 10 is normal or abnormal based on the current waveforms 311 and 312 detected by the current detection circuit 52. For example, the current waveforms 311 and 312 may be compared to determine whether the waveforms are similar, or the current waveforms 311 and 312 may be similar to any of the partial waveforms C1 and C2 stored in advance. It may be determined whether or not.

  Even if the plunger 22 operates normally during the application of the valve drive pulse 301, the plunger 22 cannot maintain the state after the application of the valve drive pulse 301 is stopped (in this case, to the core 20 side). May not be maintained), and there may be a problem of returning to the state before application of the valve drive pulse 301 (that is, a problem in which the valve open state cannot be maintained).

  In this case, as shown in FIG. 3C, when the valve driving pulse 301 is applied, the current waveform 311 in the vicinity of the rising edge is the same as the partial waveform C1 having current distortion. However, since the plunger 22 returns to the original position after that, when the valve inspection pulse 302 is applied thereafter, the plunger 22 moves again inside the coil 24, so that the current waveform 312 in the vicinity of the rise becomes a partial waveform C2. It is not similar, and becomes a waveform similar to the partial waveform C1 having current distortion again.

  There may also be a problem that the plunger 22 does not move at all (that is, a problem that the valve 22 is always closed). In this case, the current waveform 311 near the rising edge of the valve driving pulse 301 is the same as the partial waveform C2 having no current distortion.

  Although the inspection of the closed state of the electromagnetic valve 10 has been described here, the valve opening state is inspected by applying the valve drive pulse 301 and the valve inspection pulse 302 to the coil 24 so that a reverse current flows. You can also. That is, the plunger 22 does not move even when the valve drive pulse 301 is applied (a problem that the valve 22 is always open), or after the application of the valve drive pulse 301 is finished, the plunger 22 is applied to the valve seat 26 by the biasing force of the spring 34. It is possible to detect a fault that cannot return to the core 20 side without maintaining the abutted state (that is, a fault that cannot maintain the valve closed state).

  When the abnormality of the electromagnetic valve 10 is detected, the user may be notified of the abnormality through a user interface (not shown).

  Thus, by analyzing and determining the current waveforms 311 and 312 detected in the vicinity of the rising edges of the valve drive pulse 301 and the valve inspection pulse 302, the operating state of the electromagnetic valve 10 can be confirmed, and the occurrence of problems is prevented. Can be detected.

  Further, since the valve inspection pulse 302 is a pulse in the same direction as the valve driving pulse 301, the operation state can be confirmed without changing the state of the valve by the valve inspection pulse 302.

  Further, the valve inspection pulse 302 may be applied at any time, not just after the application of the valve driving pulse 301. Therefore, the valve inspection pulse 302 can be performed at a free time in consideration of other controls.

  Further, the inspection time of the valve inspection pulse 302 can be shortened by making the application time shorter than that of the valve driving pulse 301, and the power consumption required for the inspection can be reduced.

[Second Embodiment]
FIG. 4 is a schematic configuration diagram of an operation check apparatus according to the second embodiment. In addition, the same code | symbol is attached | subjected to the part which is common in the block diagram shown in FIG.

  As shown in FIG. 4, the operation check device 41 includes n valve drive drivers 58-1, 58-2, 58-3,..., 58-n, and electromagnetic valves 10-1, 10-2, 10-3,..., 10-n are connected. Control signals from the control circuit 50 are input to the valve drive drivers 58-1 to 58-n, respectively, to drive the electromagnetic valves 10-1 to 10-n.

  Each of the valve drive drivers 58-1 to 58-n has one of the power supplies connected to the reference potential and the other connected in common, and the power supply of the operation check device 41 via the current detection resistor 54. It is connected to the.

  As in the first embodiment, only one current detection circuit 52 is provided, and each of the electromagnetic valves 10-1 to 10- is output by inspection pulses output from the valve drive drivers 58-1 to 58-n. It is possible to confirm the operation of n.

  FIG. 5 is a diagram showing a valve driving pulse 301 applied to each electromagnetic valve 10-1 to 10-n from each valve driving driver 58-1 to 58-n and valve inspection pulses 302-1 to 302-n. is there. As in FIG. 3, it is assumed that the valve drive pulse 301 is a pulse for shifting from the valve closing state to the valve opening state.

  As shown in FIG. 5, the electromagnetic valves 10-1 to 10-n can be driven simultaneously. That is, by simultaneously outputting the valve drive pulse 301 from each of the valve drive drivers 58-1 to 58-n, the electromagnetic valves 10-1 to 10-n are simultaneously opened from the closed state if the operation is normal. Transition to the state.

  Next, the control circuit 50 sequentially checks the valve opening states of the electromagnetic valves 10-1 to 10-n. That is, the inspection pulses 302-1 to 302-n are output from the valve drive drivers 58-1 to 58-n with a time difference.

  The current detection circuit 52 detects a current waveform in the vicinity of the rising edge of each inspection pulse 302-1 to 302-n. As in the first embodiment, the control circuit 50 compares the detected current waveform with the partial waveforms C1 and C2, and if the detected current waveform is the same as the partial waveform C2, it is normal and the same as the partial waveform C1. If so, it is determined to be abnormal.

  Although the valve open state has been described here, the same applies to the inspection pulse in the valve closed state.

  By sequentially outputting inspection pulses in this way, even when only one current detection circuit is provided, a plurality of electromagnetic valves can be inspected.

[Detection of defects due to voltage waveforms]
In the first and second embodiments, the electromagnetic valve 10 is inspected by analyzing the drive current waveform by the current detection circuit 52. However, the inspection may be performed by detecting the voltage during driving. .

  For example, like the operation check device 42 shown in FIG. 6, a voltage detection circuit 56 is provided instead of the current detection circuit 52, and the voltage detection circuit 56 detects the voltage on the power supply side of the valve drive driver 58. Although the current detection circuit 52 detects the voltage across the current detection resistor 54, the voltage detection circuit 56 detects the voltage across the valve drive driver 58. As a result, the detection voltage of the voltage detection circuit 56 is a difference between the power supply voltage and the voltage detected by the current detection circuit 52.

  In this way, it is possible to inspect the electromagnetic valve 10 by detecting the voltage at one end of the coil 24.

[Third Embodiment]
When a malfunction of the electromagnetic valve 10 is detected as in the first and second embodiments, the electromagnetic valve 10 may be operated not only to notify the user but also to eliminate the malfunction.

  For example, when a malfunction of the electromagnetic valve 10 is detected, the valve driving pulse may be output a plurality of times. As shown in FIG. 7A, after the valve drive pulse 301 is output, a valve inspection pulse 302 is output, and the current detection circuit 52 inspects the electromagnetic valve 10. If there is an abnormality in the electromagnetic valve 10, the valve driving pulse 301 and the valve inspection pulse 302 are output again, and the current detection circuit 52 inspects the electromagnetic valve 10.

  There is a possibility that abnormal operation of the electromagnetic valve 10 has occurred due to sticking of foreign matter or the like inside the electromagnetic valve 10. In such a case, as shown in FIG. 7A, the cause of the abnormality of the electromagnetic valve 10 is removed and the normal state is restored by operating the electromagnetic valve 10 by outputting the electromagnetic valve driving pulse 301. there's a possibility that.

  In addition, when abnormality of the electromagnetic valve 10 is detected, the valve driving pulse 301 may be repeatedly output twice or more.

  In addition, when a malfunction of the electromagnetic valve 10 is detected, a valve driving pulse having a reverse phase (a pulse in which the current of the coil 24 is reversed) is output once, and then the valve is operated again in a desired state, and then restarted. An inspection may be performed.

  For example, as shown in FIG. 7B, the valve inspection pulse 302 is output after the valve driving pulse 301a is output. At this time, if it is determined that there is an abnormality in the electromagnetic valve 10, a valve driving pulse 301b having an opposite phase is output. Here, since the initial valve driving pulse 301a is a pulse for shifting from the valve closing state to the valve opening state, the anti-phase valve driving pulse 301b is a pulse for shifting from the valve opening state to the valve closing state. In addition, if the initial valve drive pulse 301a is a pulse for shifting from the valve-open state to the valve-closed state, the anti-phase valve drive pulse 301b indicates a pulse for shifting from the valve-closed state to the valve-open state.

  Then, the valve driving pulse 301a is output again, and then the valve inspection pulse 302 is output to inspect the electromagnetic valve 10.

  In this way, when an abnormality is detected in the inspection, the cause of the abnormality of the electromagnetic valve 10 is removed by operating the electromagnetic valve 10 by outputting the pulse of the opposite phase once and then outputting the pulse of the same phase again. May return to normal.

  Further, when a malfunction of the electromagnetic valve 10 is detected, a re-inspection may be performed after outputting a driving pulse whose waveform is changed from the initial driving pulse.

  For example, as shown in FIG. 7C, after outputting the valve driving pulse 301, a valve inspection pulse 302 is output, and the current detection circuit 52 inspects the electromagnetic valve 10. Here, if there is an abnormality in the electromagnetic valve 10, a valve driving pulse 301 ′ different from the valve driving pulse 301 that was initially output is output, and then a valve inspection pulse 302 is output again to inspect the electromagnetic valve 10. I do.

  Here, the initial drive pulse 301 has a rectangular waveform with a pulse width of T1, and the valve drive pulse 301 'has a rise time of T2 and a pulse width of (T2 + T3). Note that the valve driving pulse 301 ′ may change only one of the rising time and the pulse width, or may change other elements.

  As described above, when an abnormality is detected in the inspection, the cause of the abnormality of the electromagnetic valve 10 may be removed and the normal state may be restored by re-outputting the drive pulse having a different waveform and operating the electromagnetic valve 10. There is.

[Application example of electromagnetic valve inspection equipment]
FIG. 8 is a schematic diagram illustrating a configuration example of an ink supply system of the inkjet recording apparatus 100 in which the operation check apparatus according to the present invention is mounted. In FIG. 8, for convenience of explanation, only the ink supply system for one color is shown, but in the case of a plurality of colors, a plurality of components having the same configuration are provided.

  As shown in FIG. 8, the ink supply system of the inkjet recording apparatus 100 is mainly composed of a main tank 101, a buffer tank 110, a supply tank 120, a recovery tank 130, a supply pressure sensor S1, a recovery pressure sensor S2, a supply pump P1, and a recovery pump. P2, supply flow path switching device 176, recovery flow path switching device 216, maintenance unit 240, and recording head 60.

  The main tank 101 is a base tank (ink supply source) that stores ink to be supplied to the recording head 60. The main tank 101 is communicated with the buffer tank 110 via the flow path 103.

  The flow path 103 is provided with a main tank opening / closing valve 102 and a main pump P0 in order from the upstream side (main tank 101 side). The main tank opening / closing valve 102 opens and closes the flow path 103, and the latch type electromagnetic valve 10 shown in FIG. 9 is used. The main pump P0 sends ink from the main tank 101 to the buffer tank 110. When supplying ink from the main tank 101 to the buffer tank 110, the main tank opening / closing valve 102 is opened and the main pump P0 is driven. As a result, the ink in the main tank 101 is supplied to the buffer tank 110 via the flow path 103.

  When the main tank 101 is replaced, the main tank opening / closing valve 102 is closed (closed state). Thereby, ink leakage from the flow path 103 is prevented.

  Further, instead of the main tank opening / closing valve 102, there is also an aspect in which a check valve that allows only the ink flow in the direction from the main tank 101 side to the buffer tank 110 side is provided.

  The buffer tank 110 is a liquid storage unit that stores ink supplied from the main tank 101. The buffer tank 110 is in communication with a supply tank 120 and a recovery tank 130. As will be described later, the ink stored in the supply tank 120 and the recovery tank 130 moves between the supply tank 120 and the recovery tank 130 by the supply pump P1 and the recovery pump P2.

  An atmosphere communication port 112 is provided in a vertically upper portion of the buffer tank 110, and the inside of the buffer tank 110 is opened to the atmosphere through the atmosphere communication port 112. As a result, when the ink is moved between the supply tank 120 and the recovery tank 130, the internal pressure of each tank 120, 130 is reduced without losing the place where the ink flowing out from the tank 120, 130 to the buffer tank 110 side. It becomes possible to control independently.

  The supply tank 120 is configured such that the inside of the sealed container is divided into two spaces (the liquid chamber 124 and the gas chamber 126) by the flexible film 122. It is a hermetically sealed configuration.

  The supply pressure sensor S1 detects the internal pressure of the liquid chamber 124 of the supply tank 120.

  The buffer tank 110 communicates with the liquid chamber 124 of the supply tank 120 through the first communication channel 140. The first communication flow path 140 is provided with a filter 142 and a supply pump P1 in order from the upstream side (buffer tank 110 side).

  The supply pump P1 adjusts the internal pressure of the liquid chamber 124 of the supply tank 120. That is, by changing the rotation direction (drive direction) and rotation amount of the supply pump P1, the ink moves between the buffer tank 110 and the supply tank 120, and the liquid chamber 124 of the supply tank 120 has a predetermined pressure inside. Can be adjusted. For example, when the supply pump P1 is driven forward, ink flows from the buffer tank 110 side to the liquid chamber 124 side of the supply tank 120, and the internal pressure of the liquid chamber 124 of the supply tank 120 can be increased. On the other hand, when the supply pump P1 is driven in reverse, the ink flows out from the liquid chamber 124 side of the supply tank 120 to the buffer tank 110 side, and the internal pressure of the liquid chamber 124 of the supply tank 120 can be lowered.

  The flexible film 122 that partitions the internal space of the supply tank 120 is preferably composed of an elastic film (for example, rubber). Steep pressure fluctuations caused by the supply pump P1 or the recording head 60 can be attenuated by the elastic force of the flexible film 122 and the appropriate elastic force due to the compressibility of the gas chamber 126.

  In this example, air is stored in the gas chamber 126, but the gas stored in the gas chamber 126 is not particularly limited.

  The recovery tank 130 has the same configuration as the supply tank 120. That is, the inside of the sealed container is divided into two spaces (liquid chamber 134 and gas chamber 136) by a flexible film 132 (for example, rubber), and both the liquid chamber 134 and the gas chamber 136 are The inside is hermetically sealed.

  The recovery pressure sensor S2 detects the internal pressure of the liquid chamber 134 of the recovery tank 130.

  One end of the second communication channel 160 is connected to the liquid chamber 134 of the recovery tank 130. The other end of the second communication channel 160 branches into two channels (a first branch channel 160A and a second branch channel 160B). One first branch flow path 160A is connected between the filter 142 and the buffer tank 110 of the first communication flow path 140, and the other second branch flow path 160B is connected to the first communication flow path 140. Between the filter 142 and the supply pump P1.

  The first branch flow path 160A is provided with a check valve 162 that allows only the flow of ink from the collection tank 130 side to the first communication flow path 140 side. A check valve 164 that allows only ink flow from the one communication channel 140 side to the collection tank 130 side is provided.

  In this example, the first branch flow path 160A is connected to the first communication flow path 140, but may be connected to the buffer tank 110 instead of the first communication flow path 140.

  In the second communication channel 160, a recovery pump P2 is provided between the recovery tank 130 and the branch point of the channel. The recovery pump P2 adjusts the internal pressure of the liquid chamber 124 of the recovery tank 130. That is, by changing the rotation direction (drive direction) and the rotation amount of the recovery pump P2, the ink moves between the buffer tank 110 (or the supply tank 120) and the recovery tank 130, and the liquid chamber of the recovery tank 130 is obtained. The inside of 134 can be adjusted to a predetermined pressure. For example, when the recovery pump P2 is driven to rotate forward, the ink that has passed through the filter 142 from the buffer tank 110 side (first communication flow path 140 side) passes through the second branch flow path 160B and enters the liquid chamber 134 of the recovery tank 130. The internal pressure of the liquid chamber 134 of the recovery tank 130 can be increased. On the other hand, when the recovery pump P2 is driven in reverse, the ink in the liquid chamber 134 of the recovery tank 130 flows out to the buffer tank 110 side (second communication flow path 160 side) via the first branch flow path 160A, and the recovery tank The internal pressure of the 130 liquid chambers 134 can be lowered.

  The ink that has flowed from the liquid chamber 134 of the recovery tank 130 to the first communication flow path 140 via the first branch flow path 160A moves to the buffer tank 110 or passes through the filter 142 as it is to supply the supply tank. It moves to the liquid chamber 134 of the recovery tank 130 via the 120 liquid chambers 124 or the second branch flow path 160B. That is, the ink in the buffer tank 110 and the ink circulated from the supply tank 120 to the collection tank 130 via the recording head 60 as described later are removed from the foreign matters such as the thickening component by the filter 142, and then It is supplied to the tanks 120 and 130. For this reason, good ink not containing foreign matters is circulated in the recording module 60, and the ejection stability is improved.

  The liquid chamber 124 of the supply tank 120 has a supply port 66A for each of the head modules 60A, 60B,... Of the recording head 60 via the first supply channel 170, the supply valve module 172, the second supply channels 174A, 174B,. , 66B,...

  One end of the first supply channel 170 is connected to the liquid chamber 124 of the supply tank 120. The first supply channel 170 is formed such that the other end is branched into a plurality. That is, it is branched into a number corresponding to the number of head modules 60A, 60B,... Provided in the recording head 60 (three in this example for convenience of explanation). And the front-end | tip of each branched 1st supply flow path 170A, 170B, ... is connected to the end (inlet) of each supply valve 172A, 172B, ... provided in the supply valve module 172, respectively.

  The supply valve module 172 has a number of supply valves 172A, 172B,... Corresponding to the number of head modules 60A, 60B,. Each of the supply valves 172A, 172B,... Provided in the supply valve module 172 uses the latch type electromagnetic valve 10 shown in FIG. 9, and is connected to a system controller (not shown) (for example, the control circuit 50 shown in FIG. 1). Controlled and opened and closed individually. As described above, the ends of the branched first supply flow paths 170A, 170B,... Are connected to one end (inlet) of each supply valve 172A, 172,.

  One end of each of the second supply channels 174A, 174B,... Is connected to the other end (outlet) of each of the supply valves 172A, 172B,. The other ends of the second supply channels 174A, 174B,... Are connected to the supply ports 66A, 66B,... Of the head modules 60A, 60B,.

  As described above, the supply valves 172A, 172B,... Communicate with all the head modules 60A, 60B,.

The liquid chamber 134 of the recovery tank 130 includes the first recovery flow path 210 and the recovery valve module 21.
2. The recording head 60 communicates with the discharge ports 68A, 68B,... Of the head modules 60A, 60B,.

  One end of the first recovery channel 210 is connected to the liquid chamber 134 of the recovery tank 130. The first recovery channel 210 is formed by branching the other end into a plurality. That is, it is branched into a number corresponding to the number of head modules 60A, 60B,... Provided in the recording head 60 (three in this example for convenience of explanation). .. Are connected to one end (exit) of each of the recovery valves 212A, 212B,... Provided in the recovery valve module 212. The first recovery flow paths 210A, 210B,.

  The collection valve module 212 includes a number of collection valves 212A, 212B,... Corresponding to the number of head modules 60A, 60B,. Each of the recovery valves 212A, 212B,... Provided in the recovery valve module 212 uses the latch type electromagnetic valve 10 shown in FIG. 9, and is individually opened and closed under the control of a system controller (not shown). As described above, the ends of the branched first recovery flow paths 210A, 210B,... Are connected to one ends (outlets) of the recovery valves 212A, 212B,.

  One end of each of the second recovery channels 214A, 214B,... Is connected to the other end (inlet) of each recovery valve 212A, 212B,. The other ends of the second recovery channels 214A, 214B,... Are connected to the discharge ports 68A, 68B,... Of the head modules 60A, 60B,.

  Thus, by providing the supply valve and the recovery valve for each head module, it is possible to perform ink filling and maintenance for each head module. For example, it is possible to close a valve communicating with a normal head module and pressurize ink to push out deteriorated ink in the head module to the head module in which a problem has occurred.

  In the ink jet recording apparatus configured as described above, the main tank opening / closing valve 102, the supply valves 172A, 172B,..., The recovery valves are mounted by mounting the operation check devices 40, 41, 42, and the like according to the above-described embodiment. The operation states of 212A, 212B,... Can be confirmed, whereby the recording quality of the inkjet recording apparatus 100 can be maintained.

  In the above embodiment, application to an inkjet recording apparatus for graphic printing has been described as an example. However, the scope of application of the present invention is not limited to this example, and can be widely applied to various apparatuses using a latch-type electromagnetic valve. .

  DESCRIPTION OF SYMBOLS 10 ... Electromagnetic valve, 20 ... Core, 22 ... Plunger, 24 ... Coil, 34 ... Spring, 40, 41, 42 ... Operation confirmation apparatus, 50 ... Control circuit, 52 ... Current detection circuit, 54 ... Current detection resistance, 58 ... Valve drive driver, 301 ... Valve drive pulse, 302 ... Valve inspection pulse, 311, 312 ... Detection waveform, C1, C2 ... Partial waveform

Claims (10)

When the current is supplied to the coil in the first direction, the valve shifts from the valve-closed state to the valve-open state, and when the current is supplied in the second direction that is opposite to the first direction, the valve is opened. In a latch type electromagnetic valve that shifts from a state to a valve closed state, the operation check device of the latch type electromagnetic valve that maintains the state after the transition after the current supply is stopped,
Valve driving means for supplying a current in the first direction or the second direction by a driving circuit to shift the state of the latch electromagnetic valve;
Inspection driving means for supplying current in the same direction as the valve driving means by the driving circuit;
Detecting means for detecting a driving current or a driving voltage of the driving circuit based on the inspection driving;
Determination means for determining an operating state of the latch type electromagnetic valve based on the drive current or drive voltage detected by the detection means;
An operation confirmation device for a latch-type electromagnetic valve, comprising: Second detection means for detecting a drive current or a drive voltage of the drive circuit based on the valve drive;
2. The operation of the latching electromagnetic valve according to claim 1, wherein the determination unit determines an operation state of the latching electromagnetic valve based on a driving current or a driving voltage detected by the second detection unit. Confirmation device. When the current is supplied to the coil in the first direction, the valve shifts from the valve-closed state to the valve-open state, and when the current is supplied in the second direction that is opposite to the first direction, the valve is opened. In a latch type electromagnetic valve that shifts from a state to a valve closed state, the operation check device of the latch type electromagnetic valve that maintains the state after the transition after the current supply is stopped,
Valve driving means for supplying a current in the first direction or the second direction to the plurality of latch type electromagnetic valves by the respective drive circuits to shift the state of the latch type electromagnetic valve;
Inspection driving means for supplying a current in the same direction as the valve driving means by the respective driving circuits to the plurality of latch type electromagnetic valves;
A single detection means for sequentially detecting a drive current or a drive voltage of the drive circuit based on the inspection drive;
Determination means for determining individual operation states of the plurality of latched electromagnetic valves based on the drive current or drive voltage detected by the detection means;
An operation confirmation device for a latch-type electromagnetic valve, comprising:   4. The operation check device for a latch type electromagnetic valve according to claim 1, wherein a current supply time of the inspection drive means is shorter than a current supply time of the valve drive means.   A valve re-driving unit for supplying a current in the same direction as the valve driving unit to shift the state of the latching electromagnetic valve again when the determination unit determines that the operation state of the latch-type electromagnetic valve is abnormal; The operation check device for a latch type electromagnetic valve according to any one of claims 1 to 4, further comprising:   6. The operation check device for a latching electromagnetic valve according to claim 5, wherein the valve re-driving unit supplies a current with a waveform different from that of the valve driving unit.   Valve reverse driving means for supplying a current in a direction opposite to the valve driving means to shift the state of the latching electromagnetic valve when the determination means determines that the operation state of the latch electromagnetic valve is abnormal. The operation check device for a latch-type electromagnetic valve according to any one of claims 1 to 4, further comprising: An inkjet head that ejects ink;
An ink flow path for supplying the ink from an ink tank storing the ink to the inkjet head;
A latch-type electromagnetic valve for opening and closing the ink flow path;
The operation confirmation device for a latching electromagnetic valve according to any one of claims 1 to 7,
An ink jet recording apparatus comprising: When the current is supplied to the coil in the first direction, the valve shifts from the valve-closed state to the valve-open state, and when the current is supplied in the second direction that is opposite to the first direction, the valve is opened. In a method of checking the operation of a latching electromagnetic valve that is shifted from a state to a closed state and that maintains the state after the transition after the current supply is stopped,
A valve driving step of supplying a current in the first direction or the second direction by a driving circuit to shift the state of the latch electromagnetic valve;
An inspection driving process for supplying current in the same direction as the valve driving process by the driving circuit;
A detection step of detecting a drive current or a drive voltage of the drive circuit based on the inspection drive;
A determination step of determining an operation state of the latch type electromagnetic valve based on the drive current or the drive voltage detected by the detection step;
A method for confirming the operation of a latch-type electromagnetic valve, comprising: When the current is supplied to the coil in the first direction, the valve shifts from the valve-closed state to the valve-open state, and when the current is supplied in the second direction that is opposite to the first direction, the valve is opened. In a method of checking the operation of a latching electromagnetic valve that is shifted from a state to a closed state and that maintains the state after the transition after the current supply is stopped,
A valve driving step of supplying a current in the first direction or the second direction to each of the plurality of latching solenoid valves to shift the state of the latching solenoid valve;
An inspection driving step for supplying current in the same direction as the valve driving step by the respective driving circuits to the plurality of latching electromagnetic valves;
A detection step of sequentially detecting a drive current or a drive voltage of the drive circuit based on the inspection drive by a single detection means;
A determination step of determining individual operation states of the plurality of latched electromagnetic valves based on the drive current or drive voltage detected by the detection step;
A method for confirming the operation of a latch-type electromagnetic valve, comprising:

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