JP2012066517A - Recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recorder which can quickly stop operation of a recording head when oscillation is generated in the recording head.SOLUTION: An inkjet printer includes an inkjet head 2 having a drive IC 31 for driving a piezoelectric actuator 13, a control device 5 for controlling the drive IC 31, and an oscillation detecting sensor 11 which is provided in the inkjet head 2 and detects oscillation generated in the inkjet head 2. The inkjet head 2 is also provided with a switching circuit 77 for interrupting the electric power supply from a power source to the drive IC 31 when oscillation of the inkjet head 2 is detected by the oscillation detecting sensor 11.

Description

  The present invention relates to a recording apparatus that performs recording on a recording medium.

  A general recording apparatus includes a recording head including a recording element that records an image or the like on a recording medium. In this recording apparatus, for example, when it is used inside a moving body such as a train or when an earthquake occurs, the recording head also vibrates under the influence of external vibration or impact due to various factors. . When the recording operation of the recording head is performed in a state where such vibration is generated, the image quality is greatly deteriorated.

  In this regard, Patent Document 1 discloses a recording head (print head) that can reciprocate (scan) in the width direction of the paper, a print control unit that controls the recording operation of the recording head, and a vibration that detects the vibration of the recording head. An ink jet printer provided with a detection sensor is disclosed. In this printer, when a vibration of a certain level or more is detected by the vibration detection sensor, the detection signal is output to the print control unit, and in response thereto, the print control unit performs the recording operation of the recording head (image Forming operation) is stopped. In this way, wasteful consumption of ink and paper is suppressed by stopping the operation of the recording head when vibration of the recording head is detected.

JP 2007-30221 A

  In the printer of Patent Document 1, when vibration of the recording head is detected by the vibration detection sensor, a detection signal of this sensor is once output to the print control unit, and then the operation of the recording head is performed again from the print control unit. A stop command is output. For this reason, there is a time lag from when the vibration is detected until the recording operation of the recording head actually stops.

  In particular, when vibration occurs when the recording head is in a state immediately before performing the recording operation, the recording stop command is not in time due to the time lag, and recording (ink ejection) is performed slightly on the recording medium. As a result, a single recording medium may be wasted.

  In addition, when vibration occurs during recording, the recording operation proceeds with vibration occurring during the time lag, so that the image quality immediately before the stop is very poor. Therefore, when the vibration is stopped, the image recording is resumed on the same recording medium from the state when the vibration was stopped, and the recording to the recording medium is completed to the end without stopping halfway. In the recorded image, a part with a considerably low image quality is generated. That is, even if recording on the same recording medium is resumed after being interrupted, there is a high possibility that the recording medium will have to be discarded if the image quality is significantly degraded. turn into.

  An object of the present invention is to provide a recording apparatus capable of quickly stopping the operation of a recording head when vibration occurs in the recording head.

  A recording apparatus according to a first aspect of the present invention is provided in a recording element that performs recording on a recording medium, a recording head having a driving IC that drives the recording element, a control device that controls the driving IC, and the recording head. A switch comprising vibration detecting means for detecting vibration generated in the recording head, and a switch for cutting off power supply from a power source to the driving IC when vibration of the recording head is detected by the vibration detecting means. Is provided.

  If recording is performed on a recording medium in a state where a large vibration is generated in the recording head, the image quality is extremely deteriorated, and even if such recording is performed, the recording medium is only used wastefully. In the present invention, when a large vibration of the recording head is detected by the vibration detecting means, the power supply of the drive IC is cut off and the recording operation of the recording head is not performed, so that the recording medium is wasted. Is suppressed. In addition, since the recording head is provided with a switch that cuts off the power supply to the driving IC, vibration detection and the corresponding recording operation stop are completed in the recording head. Therefore, unlike the case where the recording operation of the recording head is stopped by the stop signal input again from the control device after the detection signal of the vibration detecting means is output to the control device located outside the recording head, Since there is no transmission / reception of signals between the recording heads, the recording heads can be quickly stopped. In addition, a signal line for outputting a detection signal from the vibration detecting means to the control device and outputting a stop signal from the control device to the recording head is unnecessary, which is advantageous in terms of cost.

  According to a second aspect of the present invention, there is provided a recording apparatus according to the first aspect, wherein the drive IC has a temperature detection circuit that detects an operating temperature of the drive IC, and the temperature detection circuit has an operating temperature of the drive IC. A corresponding temperature detection signal having a voltage level higher than a predetermined reference voltage is output, and the temperature detection signal is transmitted from the driving IC to the control device via a signal line, and the driving IC is transmitted by the switch. When the power supply to is cut off, the voltage level of the temperature detection signal becomes ground.

  The temperature detection circuit in the drive IC outputs a temperature detection signal at a certain voltage level corresponding to the temperature of the drive IC as long as the drive IC is operating (ON). However, when the recording head vibrates and the power supply to the drive IC is cut off by the switch, the drive IC is turned off, and the output signal of the temperature detection circuit becomes the ground level regardless of the actual operating temperature. Therefore, the control device can grasp the presence / absence of vibration of the recording head and the operating state (ON / OFF) of the driving IC based on the voltage level of the temperature detection signal input from the driving IC via the signal line. . In this configuration, since the control device can grasp the presence or absence of the vibration of the recording head using the temperature detection signal transmitted by the existing signal line, it is dedicated for transmitting the detection signal from the vibration detection means to the control device. There is no need to add additional signal lines.

  According to a third aspect of the present invention, there is provided a recording apparatus according to the first or second aspect, wherein the recording head is an ink jet head having a nozzle as the recording element that ejects ink onto the recording medium. A switch mounted on the inkjet head so as to cover the nozzle, and when the vibration generated in the inkjet head is detected by the vibration detection means when the cap is mounted on the inkjet head, the switch Is characterized in that the power supply to the drive IC is cut off.

  The present invention is based on the premise that the recording head is an inkjet head and the recording apparatus has a cap attached to the inkjet head. In the state where the cap is attached to the ink-jet head, ink is not ejected from the nozzles, so there is no need to keep the drive IC ON. Therefore, when the vibration of the head when the cap is mounted is detected by the vibration detection means, the power supply to the drive IC is cut off by the switch, thereby suppressing the power consumption (standby power) of the drive IC.

  According to the present invention, when a large vibration of the recording head is detected by the vibration detecting means, the power supply of the drive IC is cut off and the recording operation of the recording head is not performed, so that the recording medium is wasted. Is suppressed. In addition, since a switch for cutting off the power supply to the driving IC is provided in the print head, the switch between the control device and the print head is compared with the case where the print head is stopped via the control device. The recording head can be quickly stopped as long as no signal is transmitted / received at. In addition, a signal line for outputting a detection signal from the vibration detecting means to the control device and outputting a stop signal from the control device to the recording head is unnecessary, which is advantageous in terms of cost.

1 is a schematic side view of an inkjet printer 1 of the present embodiment. It is a top view of the inkjet printer of FIG. 1 is a block diagram schematically illustrating an electrical configuration of an ink jet printer. It is a top view of a head body. (A) is the A section enlarged view of FIG. 3, (b) is the BB sectional drawing of (a). It is a figure which shows the electrical structure of an inkjet head, and the electrical connection structure with a control apparatus.

  Next, an embodiment of the present invention will be described. FIG. 1 is a schematic side view of the ink jet printer 1 of the present embodiment, and FIG. 2 is a plan view of the ink jet printer 1 of FIG. FIG. 3 is a block diagram schematically showing the electrical configuration of the ink jet printer. In FIG. 2, the illustration of the rollers 40, 41, 42, etc. shown in FIG. 1 is omitted.

  As shown in FIGS. 1 to 3, the ink jet printer 1 (recording apparatus) of the present embodiment includes four fixed line type ink jet heads 2 a to 2 d (recording heads) and a sheet positioned below the ink jet head 2. A paper transport mechanism 3 that transports the recording paper P along a transport path 8 (indicated by a two-dot chain line in FIGS. 1 and 2), a maintenance unit 4 that recovers and maintains the droplet ejection performance of the ink jet head 2, and A control device 5 that controls the entire printer 1 is provided.

  First, the inkjet head 2 will be described. The fixed line type inkjet head 2 includes a head body 10 that faces the paper transport path 8. On the lower surface of the head main body 10 (the surface facing the paper conveyance path 8), the paper width direction (main scanning direction: the direction perpendicular to the paper surface in FIG. 1, the left-right direction in FIG. 2) perpendicular to the conveyance direction of the recording paper P A number of nozzles are arranged along the line. Each of the four inkjet heads 2a to 2d is configured to eject ink of four colors of yellow, magenta, cyan, and black from the nozzle 14, and as shown in FIGS. The two inkjet heads 2a to 2d are arranged side by side in the transport direction (sub-scanning direction). The ink jet head 2 is provided with a vibration detection sensor 11 (vibration detection means) that detects vibration generated in the head 2. As the vibration detection sensor 11, a known sensor such as an acceleration sensor or an angle sensor can be used. The reason why the vibration detection sensor 11 is provided will be described later.

  4 is a plan view of the head main body 10, FIG. 5A is an enlarged view of a portion A in FIG. 3, and FIG. 4B is a sectional view taken along line BB in FIG. As shown in FIGS. 4 and 5, the head body 10 of each inkjet head 2 includes a flow path unit 12 in which an ink flow path including nozzles 14 is formed, and a piezoelectric actuator 13 disposed on the upper surface of the flow path unit 12. And.

  The flow path unit 12 has a structure in which four plates are laminated, and a plurality of nozzles 14 arranged in two rows in a staggered manner along the transport direction and a plurality of pressures respectively communicating with the plurality of nozzles 14. An ink flow path including a chamber 15 and a manifold 16 that communicates with the plurality of pressure chambers 15 in common is formed. The plurality of nozzles 14 are opened on the lower surface of the flow path unit 12, while the plurality of pressure chambers 15 communicating with the plurality of nozzles 14 are opened on the upper surface of the flow path unit 12, and the plurality of pressure chambers 15 are the piezoelectric actuators 13. It is the structure blocked by. The manifold 16 is connected to an ink supply port 17 opened on the upper surface of the flow path unit 12, and ink supplied from an ink tank (not shown) to the ink supply port 17 flows into the manifold 16. As shown in FIG. 5B, the flow path unit 12 is formed with a plurality of individual ink flow paths 18 from the manifold 16 through the pressure chambers 15 to the nozzles 14.

  The piezoelectric actuator 13 is disposed on the upper surface of the flow path unit 12 so as to cover the plurality of pressure chambers 15, the piezoelectric layer 21 stacked on the upper surface of the vibration plate 20, and the upper surface of the piezoelectric layer 21. The plurality of individual electrodes 22 are provided.

  The vibration plate 20 is formed of a metal material, and is joined to the flow path unit 12 in a state of being disposed on the upper surface of the flow path unit 12 so as to cover the plurality of pressure chambers 15. In addition, the upper surface of the conductive diaphragm 20 is disposed on the lower surface side of the piezoelectric layer 21, thereby generating an electric field in the thickness direction in the piezoelectric layer 21 with the plurality of individual electrodes 22 on the upper surface. Also serves as an electrode. The diaphragm 20 as the common electrode is connected to a ground wiring of a drive IC 31 described later and is always held at the ground potential.

  The piezoelectric layer 21 is made of a piezoelectric material mainly composed of lead zirconate titanate (PZT), which is a solid solution of lead titanate and lead zirconate and is a ferroelectric material, and is formed in a flat plate shape. As shown in FIGS. 4 and 5B, the piezoelectric layer 21 is continuously formed across the plurality of pressure chambers 15 on the upper surface of the diaphragm 20.

  A plurality of individual electrodes 22 are respectively arranged in regions on the upper surface of the piezoelectric layer 21 facing the plurality of pressure chambers 15. Further, a plurality of contact portions 23 are drawn out from the end portions of the plurality of individual electrodes 22, respectively. A plurality of piezoelectric layer portions (active portion 26: see FIG. 5 (b)) sandwiched between the plurality of individual electrodes 22 and the diaphragm 20 as a common electrode are previously polarized in the thickness direction. Yes.

  As shown in FIGS. 4 and 5B, a COF (Chip On Film) in which a drive IC 31 for driving the piezoelectric actuator 13 is mounted so as to cover the upper surface on which the plurality of contact portions 23 of the piezoelectric actuator 13 are arranged. 30 is arranged, and the plurality of contact portions 23 are connected to contact portions 32 provided on the back surface of the COF 30. Then, the drive IC 31, the plurality of individual electrodes 22, and the diaphragm 20 as a common electrode are electrically connected via a wiring (not shown) formed in the COF 30. The COF 30 is further connected to the control device 5 of the printer 1. The drive IC 31 receives a command from the control device 5, supplies a drive pulse signal to each of the plurality of individual electrodes 22, and applies a predetermined drive voltage to the active unit 26.

  Next, the operation of the piezoelectric actuator 13 when the drive pulse signal is supplied will be described. When a driving pulse signal is supplied from a driving IC 31 to a certain individual electrode 22, an active portion 26 sandwiched between the individual electrode 22 and the diaphragm 20 as a common electrode held at the ground potential A predetermined drive voltage is applied, whereby an electric field in the thickness direction acts on the active portion 26. Since the direction of the electric field is parallel to the polarization direction of the active portion 26, the active portion 26 contracts in a plane direction perpendicular to the thickness direction. Here, since the lower vibration plate 20 of the piezoelectric layer 21 is fixed to the upper surface of the flow path unit 12, as the piezoelectric layer 21 positioned on the upper surface of the vibration plate 20 contracts in the surface direction, The portion of the diaphragm 20 that covers the pressure chamber 15 is deformed so as to be convex toward the pressure chamber 15 (unimorph deformation). At this time, since the volume in the pressure chamber 15 decreases, the ink pressure in the pressure chamber 15 rises, and ink is ejected from the nozzle 14 communicating with the pressure chamber 15.

  In the present embodiment, the nozzle 14 and one active portion 26 of the piezoelectric actuator 13 that ejects ink droplets from the nozzle 14 correspond to the recording element in the present invention.

  Returning to FIG. 1, the paper transport mechanism 3 includes a pickup roller 40, a paper feed roller 41, a paper discharge roller 42, and drive motors 46, 47, and 48 for driving these rollers 40, 41, and 42 (see FIG. 1). 3), and the recording paper P taken out from the paper feed tray 43 is transported along the paper transport path 8. That is, one sheet is taken out of the recording paper P stacked in the paper feed tray 43 by the pickup roller 40, and the taken out recording paper P is cooperated by the paper feed roller 41 and the driven roller 44 to the inkjet head 2. Further, the recording paper P after the image or the like is recorded by the inkjet head 2 is discharged by the paper discharge roller 42 and the spur roller 45.

  As shown in FIGS. 1 and 2, the maintenance unit 4 includes a cap 50 attached to the lower surfaces (ink ejection surfaces) of the four inkjet heads 2, and a suction pump 51 connected to the cap 50. The cap 50 is located at the capping position facing the lower surface of the inkjet head 2 (a position on the opposite side of the paper with respect to the inkjet head 2 in FIG. 2), and the retracted position retracted from the inkjet head 2 in the main scanning direction (shown in FIG. 2). It is configured to be movable over a certain position). Further, the cap 50 is configured to be driven up and down by a cap drive motor 53 (see FIG. 3) so as to be in contact with and away from the ink ejection surface when in the capping position. Further, the cap 50 includes four cap portions 50 a that respectively cover the nozzles 14 when they are in close contact with the four inkjet heads 2. The suction pump 51 is connected to the cap 50 via a switching unit 52, and the switching unit 52 switches the communication destination with the suction pump 51 between the four cap portions 50a.

  The maintenance unit 4 covers the nozzles 14 of the four inkjet heads 2 with caps 50, thereby preventing the nozzles 14 from drying in a standby state where ink is not ejected. Further, by performing a suction purge for sucking ink from the nozzle 14 by the suction pump 51 at an appropriate timing, and discharging foreign matter and bubbles mixed in the ink or thickened ink together with the ink from the nozzle 14, The droplet ejection performance of the inkjet head 2 is recovered and maintained.

  Next, the electrical configuration of the inkjet printer 1 will be described with reference to the block diagram of FIG. As shown in FIG. 3, the control device 5 has an ASIC (Application Specific Integrated Circuit) 60, and this ASIC 60 is connected to an external device PC (Personal Computer) 66 via an input / output interface so that data communication is possible. Each unit of the printer 1 is controlled based on image data or the like input from the PC 66. Specifically, the ASIC 60 includes a head control circuit 61 that controls the drive IC 31 of the inkjet head 2, a transport control circuit 62 that controls the drive motors 46 to 48 of the paper transport mechanism 3, and a cap drive motor of the maintenance unit 4. 53 and a maintenance control circuit 63 for controlling the suction pump 51 are incorporated.

  Furthermore, the electrical configuration of the inkjet head 2 will be described in more detail. FIG. 6 is a diagram illustrating an electrical configuration of the inkjet head 2 and an electrical connection configuration with the control device 5. As shown in FIG. 6, the inkjet head 2 has a relay board 70 integrally attached to the head body 10 (see FIGS. 4 and 5), and the control board 5 and the relay board 70 of the inkjet head 2 are wired. They are connected by a substrate 71. On the other hand, as described above, the COF 30 on which the drive IC 31 is mounted is connected to the piezoelectric actuator 13 of the inkjet head 2, and this COF 30 is also connected to the relay substrate 70. That is, the control IC 5 and the drive IC 31 of the inkjet head 2 are connected via the relay substrate 70 so as to be able to transmit and receive signals.

  Further, a power supply (not shown) is connected to the control device 5, and a power supply voltage (VDD) is supplied from the control device 5 to the drive IC 31 via the power supply wiring 72 on the wiring board 71 and the relay board 70. It has become so. Further, the relay board 70 is provided with a switch circuit 77 for cutting off power supply from the power source to the drive IC 31.

  When the inkjet head 2 performs a recording operation (ink ejection operation), the control signal input from the control device 5 to the drive IC 31 of the inkjet head 2 is not described in detail, but the clock signal (CLK) and the drive are not described. There are a plurality of types of pulse waveform signals (FIRE) for generating a pulse signal, a waveform selection signal (SIN) for selecting one from a plurality of types of pulse waveform signals, and the like. The signal is input from the control device 5 to the relay substrate 70 through the wirings 73, 74, and 75 formed on the wiring substrate 71 and further input to the driving IC 31. The drive IC 31 generates a drive pulse signal using the signal and outputs it to the piezoelectric actuator 13.

  In addition, a temperature detection circuit 78 composed of a transistor thermistor for detecting the operating temperature of the drive IC 31 is incorporated in the drive IC 31. Then, a temperature detection signal (V-TEMP) from the temperature detection circuit 78 of the drive IC 31 is input to the control device 5 via a wiring (signal line) 76 formed on the relay substrate 70 and the wiring substrate 71. Note that the temperature detection signal output from the temperature detection circuit 78 is a signal having a voltage level that is always higher than the ground level, corresponding to the operating temperature of the drive IC 31, in accordance with the temperature characteristics unique to the thermistor. Thereby, the control apparatus 5 can grasp | ascertain the operating temperature of drive IC31 from the voltage level of a temperature detection signal (V-TEMP), and when the temperature of drive IC31 exceeds predetermined temperature (for example, 100 degreeC), In order to prevent destruction of the drive IC 31 due to overheating, measures such as stopping the drive of the piezoelectric actuator 13 by the drive IC 31 are taken.

  Further, the inkjet head 2 is provided with a vibration detection sensor 11 that detects the vibration of the inkjet head 2. The vibration detection sensor 11 outputs a signal having a higher voltage level as the vibration (amplitude) increases, and the output (vibration detection signal) is input to the comparator 79 and compared with the reference voltage (Vref). When a vibration of a certain level or larger is generated in the inkjet head 2, the vibration detection signal output from the vibration detection sensor 11 becomes higher than the reference voltage (Vref), and the comparator 79 outputs an H signal (High). ) Is output. Otherwise, the comparator 79 outputs an L signal (Low).

  The output of the comparator 79 is input to the switch circuit 77 of the relay board 70. In FIG. 6, a latch circuit 80 is provided between the comparator 79 and the switch circuit 77, but the description of the latch circuit 80 is omitted here and will be described in detail later. When the vibration of the inkjet head 2 is small (the voltage level of the vibration detection signal is low) and the L signal is input from the comparator 79 to the switch circuit 77, the switch circuit 77 is turned on, and the power from the power source to the drive IC 31 Supply continues. On the other hand, when a large vibration exceeding a certain level is generated in the inkjet head 2 and an H signal is input from the comparator 79 to the switch circuit 77, the switch circuit 77 is turned off and the power supply from the power source to the drive IC 31 is cut off. . When the power supply to the drive IC 31 is cut off by the switch circuit 77, the drive IC 31 is turned off, so that the drive of the piezoelectric actuator 13 by the drive IC 31 (that is, the recording operation of the ink jet head 2) is quickly stopped, and the vibration is reduced. Until then, the driving of the piezoelectric actuator 13 is prohibited.

  Thereafter, when the vibration of the inkjet head 2 is stopped and the voltage level of the vibration detection signal output from the vibration detection sensor 11 becomes lower than the reference voltage (Vref), the switch circuit 77 returns to ON and the power to the drive IC 31 is restored. Supply is resumed.

  As described above, when a large vibration is generated in the inkjet head 2 and detected by the vibration detection sensor 11, the switch circuit 77 cuts off the power supply of the drive IC 31, and the recording operation of the inkjet head 2 is not performed. That is, it is possible to prevent a recording operation with a low image quality from being performed during the occurrence of vibration, and to prevent the recording paper P from being wasted. Also, the ink is not wasted.

  Further, since the ink jet head 2 is provided with a switch circuit 77 that cuts off the power supply to the drive IC 31, the switch circuit 77 is instantaneously turned off when vibration is detected by the vibration detection sensor 11. The power supply to is quickly cut off. Therefore, the recording operation of the inkjet head 2 is compared with a configuration in which the detection signal of the vibration detection sensor 11 is temporarily transmitted to the control device 5 and the stop signal is transmitted again from the control device 5 to the drive IC 31. Can be stopped (prohibited) promptly. In addition, it is not necessary to provide the wiring board 71 with a signal line for outputting a detection signal from the vibration detection sensor 11 to the control device 5 and outputting a stop signal from the control device 5 to the inkjet head 2. It is advantageous in terms of cost.

  In the present embodiment, the temperature detection signal (V-TEMP) at the voltage level corresponding to the operating temperature of the drive IC 31 output from the temperature detection circuit 78 of the drive IC 31 is transmitted via the signal line 76 of the wiring board 71. It is transmitted to the control device 5. As long as the drive IC 31 is ON, the voltage level of the temperature detection signal is higher than the ground level. However, as described above, when the power supply to the drive IC 31 is interrupted when vibration is generated and the drive IC 31 is turned off, the temperature detection signal becomes the ground level regardless of the actual operating temperature.

  Therefore, the control device 5 vibrates the inkjet head 2 depending on whether the voltage level of the temperature detection signal input from the driving IC 31 via the single signal line 76 is the ground level or a higher voltage level. The presence or absence of occurrence and the operating state (ON / OFF) of the drive IC 31 can be grasped. Further, since the control device 5 can grasp the presence or absence of vibration of the inkjet head 2 using the temperature detection signal transmitted through the existing signal line 76, the detection signal is transmitted from the vibration detection sensor 11 to the control device 5. Therefore, it is not necessary to add a dedicated signal line to the wiring board 71.

  As described above, when the control device 5 can grasp the presence or absence of vibration of the inkjet head 2 (ON / OFF of the drive IC 31), it controls other configurations of the printer 1 in accordance with the occurrence of the vibration. It becomes possible to do. For example, the following control can be considered.

  In the present embodiment, the stop of the recording operation of the ink jet head 2 at the time of occurrence of vibration is performed in the ink jet head 2, not by a command from the control device 5. Therefore, if the control device 5 cannot grasp the operation state of the ink jet head 2, the paper transport mechanism 3 transports the recording paper P with a predetermined feed amount assuming that the recording operation of the ink jet head 2 is normally performed. Will be a waste of time. However, if the control device 5 can grasp the occurrence of vibration of the inkjet head 2, the conveyance of the recording sheet P by the sheet conveyance mechanism 3 can be stopped in accordance with the stop of the operation of the inkjet head 2. Alternatively, the recording paper P sent to the inkjet head 2 for image recording may be once discharged.

  By the way, in the above description, it has been described that the power supply to the drive IC 31 is cut off in order to prevent a useless recording operation with low image quality from being performed when vibration occurs. However, in the configuration of the printer 1 of the present embodiment, the detection result of the vibration detection sensor 11 is used for the purpose of suppressing the power consumption (standby power) of the drive IC 31 when the inkjet head 2 does not perform the recording operation. It is also possible to cut off the power supply to the drive IC 31.

  When the inkjet head 2 is not used, a cap 50 (see FIG. 2) is attached to the lower surface (ink ejection surface) of the inkjet head 2 to cover the nozzle 14 in order to prevent the ink in the nozzle 14 from drying. Here, when the cap 50 is mounted, the cap 50 is pressed against the inkjet head 2 by the cap drive motor 53, and at this time, slight vibration is generated in the inkjet head 2. When the vibration of the inkjet head 2 when the cap 50 is mounted is detected by the vibration detection sensor 11, the switch circuit 77 is turned off and the power supply to the drive IC 31 is cut off. Further, when the cap 50 is attached to the ink jet head 2 to perform the suction purge of the ink jet head 2, the same vibration as above occurs, so that the power supply to the drive IC 31 is cut off by the switch circuit 77. .

  As described above, when the cap 50 is attached, the power supply to the drive IC 31 is interrupted by the switch circuit 77, so that the power consumption (standby power) of the drive IC 31 is suppressed. If the inkjet head 2 is configured to be swingable (tilted) by a small angle when the cap 50 is mounted, vibration generated in the inkjet head 2 when the cap 50 is mounted increases and is detected by the vibration detection sensor 11. It becomes easy.

  However, in order to continuously cut off the power to the drive IC 31 while the cap 50 is mounted, the vibration when the cap 50 is mounted is detected by the vibration detection sensor 11 and the switch circuit 77 is turned off. After that, it is necessary to maintain the OFF state until the clock signal is output from the ASIC 60 in order to perform recording. On the other hand, at the time of recording on the recording paper P, the switch circuit 77 is quickly turned off so that the recording operation of the inkjet head 2 can be resumed immediately after the switch circuit 77 is once turned off due to the vibration. It is preferable to return to ON. Therefore, when recording on the recording paper P, the switch circuit 77 is switched ON / OFF according to the detection result of the vibration detection sensor 11, while when the cap 50 is attached, the switch circuit 77 is switched on. A circuit configuration in which the OFF state is maintained is adopted.

  A specific example of the circuit configuration will be described. As shown in FIG. 6, a latch circuit 80 is provided between the output of the comparator 79 and the input of the switch circuit 77. The latch circuit 80 also receives a clock signal (CLK) sent from the ASIC 60 at a predetermined clock frequency.

  When vibration of the inkjet head 2 is detected by the vibration detection sensor 11 and an H signal is input from the comparator 79, the latch circuit 80 outputs the H signal to the switch circuit 77 and turns off the switch circuit 77. However, when the vibration is subsequently stopped and the L signal is input from the comparator 79, the latch circuit 80 outputs the L signal to the switch circuit 77 only when the clock signal (CLK) is input. When the clock signal is not input, the H signal is continuously output. Specifically, the latch circuit 80 outputs the signal (H signal or L signal) input from the comparator 79 to the switch circuit 77 at the timing when the clock signal input from the ASIC 60 becomes H.

  Since the clock signal is input to the latch circuit 80 during recording on the recording paper P, the latch circuit 80 outputs to the switch circuit 77 according to the vibration detection result of the vibration detection sensor 11 at the timing when the clock signal becomes H. The signal is updated as needed, and the vibration of the inkjet head 2 is reflected in real time on the ON / OFF of the switch circuit 77.

  On the other hand, the clock signal is not input to the latch circuit 80 when the cap 50 is attached. Therefore, after the vibration when the cap 50 is mounted is detected by the vibration detection sensor 11 and the latch circuit 80 outputs the H signal to the switch circuit 77 (the switch circuit 77 is OFF), the vibration is reduced and the comparator 79 outputs L. Even if the signal is input, the latch circuit 80 continues to output the H signal to the switch circuit 77. That is, the switch circuit 77 holds the OFF state until a clock signal is output from the ASIC 60 for recording.

  Next, modified embodiments in which various modifications are made to the embodiment will be described. However, the same reference numerals are given to those having the same configuration as in the above embodiment, and the description thereof is omitted as appropriate.

1] In the above-described embodiment, the control device 5 grasps whether or not the inkjet head 2 generates vibration from the voltage level of the temperature detection signal. However, the detection signal of the vibration detection sensor 11 is sent to the switch circuit 77. In addition, it may be configured to be transmitted directly to the control device 5.

  Further, even when the control device 5 does not grasp the presence or absence of vibration of the ink jet head 2, the paper transport mechanism 3 only keeps feeding the recording paper P, which is not a big problem. A configuration in which a signal is not sent to the control device 5 may be adopted.

2] Although the inkjet head 2 of the above embodiment is a fixed line type head that does not move during the recording operation, it is a so-called serial type inkjet head that ejects ink while reciprocating in the width direction of the recording paper P. The present invention can also be applied to.

3] The ink jet head is not limited to ejecting ink by a piezoelectric actuator, and other types of actuators, for example, a method of ejecting ink using evaporation when heated by a heating body are used. You can also.

  The present invention is not limited to an ink jet printer, and can also be applied to a recording apparatus that employs another recording method, such as a dot impact type printer.

DESCRIPTION OF SYMBOLS 1 Inkjet printer 2 Inkjet head 5 Control apparatus 11 Vibration detection sensor 13 Piezoelectric actuator 14 Nozzle 31 Drive IC
50 Cap 77 Switch circuit 78 Temperature detection circuit P Recording paper

Claims (3)

A recording head for recording on a recording medium and a recording head having a drive IC for driving the recording element;
A control device for controlling the drive IC;
Provided with the recording head, comprising vibration detecting means for detecting vibration generated in the recording head,
A recording apparatus, wherein the recording head is provided with a switch that cuts off power supply from a power source to the driving IC when vibration of the recording head is detected by the vibration detecting means. The drive IC has a temperature detection circuit that detects an operating temperature of the drive IC,
The temperature detection circuit outputs a temperature detection signal having a voltage level higher than a predetermined reference voltage corresponding to the operating temperature of the drive IC, and the temperature detection signal is output from the drive IC via a signal line. Transmitted to the control device,
The recording apparatus according to claim 1, wherein when the power supply to the driving IC is cut off by the switch, the voltage level of the temperature detection signal becomes ground. The recording head is an ink jet head having a nozzle as the recording element that ejects ink onto the recording medium;
A cap attached to the inkjet head so as to cover the nozzle;
The switch cuts off power supply to the drive IC when vibration generated in the ink-jet head when the cap is attached to the ink-jet head is detected by the vibration detection means. Item 3. The recording apparatus according to Item 1 or 2.