JP2023019791A - Liquid ejector - Google Patents

Abstract

To enable miniaturization of a device.SOLUTION: A liquid discharge device includes: an inkjet head having nozzles for discharging ink; a solenoid valve for selectively taking any one of a communication state where an ink storage chamber for storing ink and an atmosphere communication path for communicating the ink storage chamber and outside are communicated with each other, and a cut-off state where the atmosphere communication path is cut off; a power source 6 for generating a voltage; a power source line 8a connected to the power source 6; and a voltage supply part 90 for supplying the voltage that is generated by the power source 6 and input through the power source line 8a, to the inkjet head and the solenoid valve. The voltage supply part 90 can switch a supply destination of the voltage between the inkjet head and the solenoid valve.SELECTED DRAWING: Figure 6

Description

The present invention selectively adopts either a communicating state in which an atmosphere communication passage for communicating a liquid storage chamber communicating with a liquid ejection head and the outside is communicated, or a blocking state in which the atmosphere communication passage is blocked. relates to a liquid ejecting apparatus having an electrically driven valve capable of

Japanese Unexamined Patent Application Publication No. 2002-100003 describes an inkjet recording apparatus that stores ink supplied from an ink tank in an ink buffer, and ejects the ink onto a recording medium from a print head on a carriage to perform a recording operation. In this ink jet recording apparatus, during the ink supply in which the ink in the ink tank is supplied to the ink buffer, the electromagnetic valve for opening to the atmosphere, which controls communication between the upper air layer in the ink buffer and the atmosphere, is opened. . This allows the air in the upper part of the ink buffer to escape when ink is supplied, and the ink in the ink buffer is not pressurized. In this ink jet recording apparatus, during purging, the atmospheric release electromagnetic valve is closed, and pressurized ink is supplied from the ink tank to perform the purging operation.

Japanese Utility Model Publication No. 01-040681

Thus, Patent Document 1 describes an ink jet recording apparatus having an electromagnetic valve for opening to the atmosphere. However, Japanese Patent Laid-Open No. 2002-100001 describes details about a power supply that generates voltage to be supplied to the atmospheric release electromagnetic valve and the print head, and a power supply line that supplies the voltage generated by the power supply to the atmospheric release electromagnetic valve and the print head. It has not been. For example, the voltage supplied to the atmospheric release electromagnetic valve and the voltage supplied to the print head are normally generated by separate power supplies, and are supplied to the atmospheric release electromagnetic valve and the print head via separate power supply lines. supplied. In this case, a space for installing a plurality of power sources and a plurality of power lines is required, and there is a problem that the size of the device increases.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a liquid ejecting apparatus that can be miniaturized.

A liquid ejection device according to the present invention includes a liquid ejection head having a nozzle for ejecting liquid, a liquid storage chamber for storing liquid, an atmosphere communication passage for communicating the liquid storage chamber with the outside, and the atmosphere communication passage. a liquid reservoir having an electrically driven valve capable of selectively taking either one of a communication state in which the air communication path is communicated and a cutoff state in which the atmosphere communication path is cut off; the liquid ejection head and the liquid storage chamber; a liquid flow path to which a liquid is circulated, a power source for generating a voltage, a power line connected to the power source, and a voltage generated by the power source and input via the power line to the liquid ejection a supply unit that supplies voltage to the head and the valve, and the supply unit is capable of switching the voltage supply destination.

According to the liquid ejecting apparatus of the present invention, the voltage generated by one power source and input to the supply section through one power line can be supplied to the liquid ejecting head and the valve. Therefore, the number of power sources and the number of power lines can be reduced, so that the size of the device can be reduced.

1 is a schematic perspective view of a printer according to a first embodiment of the invention; FIG. 2 is a longitudinal sectional view schematically showing the internal structure of the printer shown in FIG. 1; FIG. The ink tank and the inkjet head shown in FIG. 2 are shown, (a) is a front view, and (b) is a side view. 4 is a plan view of the inkjet head shown in FIG. 3; FIG. FIG. 5 is a cross-sectional view taken along the line VV shown in FIG. 4; It is a figure which shows the installation condition of a control board, a relay board, and FFC which connects these board|substrates. 7 is a circuit diagram of the voltage supply unit shown in FIG. 6, where (a) shows a case where the voltage from the power supply is being input, and (b) shows a case where the voltage from the power supply is stopped; FIG. 2 is a block diagram showing an electrical configuration of the printer of FIG. 1; FIG. FIG. 10 is a diagram showing the installation status of a control board, a relay board, and an FFC connecting these boards in the printer according to the second embodiment of the invention;

(First embodiment)
A printer 1 according to a first embodiment of the present invention will be described below. The printer 1 is installed and used in the state shown in FIG. In this embodiment, the three directions indicated by arrows in FIG. 1 are the up-down direction A1, the front-rear direction A2, and the left-right direction A3. 2 to 6 also reflect the three directions shown in FIG.

<Overview of Printer 1>
As shown in FIG. 1, the printer 1 has a generally rectangular parallelepiped housing 11 . An opening 12 is formed substantially in the center of the front wall 11 a of the housing 11 . A paper feed tray 15 and a paper discharge tray 16 are provided in two upper and lower stages in the opening 12 . The paper feed tray 15 is configured to be insertable/removable from the opening 12 in the front-rear direction A<b>2 , that is, detachable from the housing 11 . A sheet P of a desired size (for example, A4 size) is placed on the paper feed tray 15 . The printer 1 can be connected to an external device such as a personal computer (hereinafter referred to as PC). Then, a recording operation is executed based on recording data from a PC or the like.

As shown in FIG. 1, an operation portion 13 is provided on the upper portion of the front wall 11a. The operation unit 13 includes buttons operated for various settings, a liquid crystal display on which various information is displayed, and the like. In this embodiment, the operation unit 13 is configured by a touch panel having both button and liquid crystal display functions.

The housing 11, as shown in FIGS. 1 and 2, has an opening/closing cover 14 that constitutes its ceiling. The opening/closing cover 14 is configured to be rotatable at its rear end about a rotation axis (not shown) extending in the left-right direction A3. By opening the opening/closing cover 14, an ink tank 61, which will be described later, arranged in the housing 11 is exposed, and ink can be injected into the ink tank 61 to replenish it.

<Internal Structure of Printer 1>
Next, the internal structure of the printer 1 will be explained. As shown in FIG. 2, the printer 1 includes a feeding unit 20, a conveying roller pair 35, a recording unit 40, a paper discharge roller pair 36, an ASF (Auto Sheet Feed) motor 20M (see FIG. 8), It includes an LF (Line Feed) motor 30M (see FIG. 8), a control unit 5 (see FIG. 8), and a power source 6 (see FIGS. 6 and 8).

The feeding unit 20 feeds the paper P placed on the paper feed tray 15 to the transport path 25, as shown in FIG. The transport roller pair 35 transports the paper P fed by the feeding unit 20 to the recording unit 40 . The recording unit 40 has, for example, an inkjet recording system configuration, and records an image on the paper P transported by the transport roller pair 35 . The paper discharge roller pair 36 discharges the paper P recorded by the recording unit 40 to the paper discharge tray 16 .

<Feeding unit 20>
As shown in FIG. 2 , the feeding section 20 is provided above the paper feed tray 15 . The feeding section 20 has a feeding roller 21 and an arm 22 . The paper feed roller 21 is pivotally supported at the tip of the arm 22 . The arm 22 is rotatably supported by a support shaft 22a. The arm 22 is urged by a spring or the like in a direction in which the paper feed roller 21 contacts the paper feed tray 15 (in a direction to rotate downward). Further, the arm 22 is configured to be retractable upward when the paper feed tray 15 is attached or detached. The paper feed roller 21 is rotated by power transmitted from the ASF motor 20M via a transmission mechanism (not shown). As a result, the paper P stacked in the paper feed tray 15 is fed to the transport path 25 .

<Paper tray 15>
As shown in FIG. 2, the paper feed tray 15 has an inclined wall portion 15a. The inclined wall portion 15 a guides the paper P to the transport path 25 when the paper P placed on the paper feed tray 15 is fed by the paper feed roller 21 .

<Conveyance path 25>
The transport path 25 is configured within the housing 11 and, as shown in FIG. The paper P fed from the paper feed tray 15 is guided by the transport path 25 so as to make a U-turn from the bottom to the top and reaches the recording section 40 .

<Conveyance Roller Pair 35 and Discharge Roller Pair 36>
The conveying roller pair 35 has a conveying roller 35a arranged on the lower side and a pinch roller 35b arranged on the upper side. The transport roller 35a is rotated by power transmitted from the LF motor 30M via a transmission mechanism (not shown). The pinch roller 35b rotates together with the rotation of the conveying roller 35a. The transport roller 35 a and the pinch roller 35 b rotate while pinching the paper P in the vertical direction A<b>1 to transport the paper P to the recording unit 40 .

The paper discharge roller pair 36 has a lower paper discharge roller 36a and an upper spur roller 36b. The paper discharge roller 36a is rotated by power transmitted from the LF motor 30M via a transmission mechanism (not shown). The spur roller 36b rotates with the rotation of the discharge roller 36a. The paper discharge roller 36 a and the spur roller 36 b rotate while nipping the paper P in the vertical direction A<b>1 to convey the paper P to the paper discharge tray 16 .

<Recording unit 40>
As shown in FIGS. 2 and 3, the recording unit 40 includes an inkjet head 41, an ink tank 61, a relay board 80 (a "sub-board" of the present invention), a carriage 70, a moving mechanism 71, a platen 17, and a and The carriage 70 reciprocates in the scanning direction (horizontal direction A3 and perpendicular to the transport direction of the paper P). The inkjet head 41 and ink tanks 61 are supported by a carriage 70 . In other words, the printer 1 according to this embodiment is a so-called on-carriage type in which the ink tank 61 and the inkjet head 41 are mounted on the carriage 70 . The entirety of the ink tank 61 in this embodiment is positioned above the inkjet head 41 . However, without being limited to this, a part of the ink tank 61 may be positioned above the upper surface of the inkjet head 41 and the remaining part may be positioned below the upper surface.

<Ink tank 61>
The ink tank 61 has a tank body 62, a cap 63, and an electromagnetic valve 64, as shown in FIG. The tank main body 62 has a substantially rectangular parallelepiped shape, and an ink storage chamber 62a for storing ink is formed therein. Black ink is stored in the ink storage chamber 62a.

As shown in FIG. 3, the tank body 62 is formed with a through hole 62c passing through its upper wall 62b. The through-hole 62c is arranged in the center of the upper wall 62b in the left-right direction A3 and slightly forward. A cylindrical body 66 is fitted in the through hole 62c. The cylinder 66 has an ink inlet 67 at its upper end. The ink inlet 67 is an opening that opens upward (that is, to the outside). The inner peripheral surface of the cylindrical body 66 defines an ink supply path 66a extending from the ink inlet 67 to the ink storage chamber 62a. The ink inlet 67 communicates the ink storage chamber 62a with the outside.

The cap 63 shown in FIG. 3 is made of flexible resin, for example. The cap 63 can be attached to and detached from the upper end portion of the cylindrical body 66 by user operation, and closes or opens the ink inlet 67 . The ink injection port 67 is normally closed by a cap 63, and is opened by removing the cap 63 from the cylinder 66 when injecting ink into the ink storage chamber 62a.

As shown in FIG. 3B, the tank main body 62 is formed with an atmospheric communication passage 62e that penetrates the rear side wall 62d and communicates the ink storage chamber 62a with the outside. The atmospheric communication passage 62e is arranged near the upper end of the rear side wall 62d.

As shown in FIG. 3B, the electromagnetic valve 64 is a known two-way electromagnetic valve and has a valve portion 64a and a solenoid portion 64b. The electromagnetic valve 64 is fixed to the upper wall 62b. The valve portion 64a is arranged in the ink storage chamber 62a and has an internal flow passage (not shown) communicating with the air communication passage 62e and the ink storage chamber 62a and a valve (not shown) for opening and closing the internal flow passage. ing. The solenoid portion 64b is arranged on the upper wall 62b and opens and closes the valve of the valve portion 64a.

When the solenoid portion 64b is not supplied with voltage, the electromagnetic valve 64 is in a cutoff state (that is, the valve closes the internal passage) to cut off the communication between the air communication passage 62e and the ink storage chamber 62a. . The solenoid portion 64b of the electromagnetic valve 64 is supplied with a voltage generated by the power supply 6 (FIGS. 6 and 8), and the valve portion 64a is in a communication state in which the atmosphere communication passage 62e and the ink storage chamber 62a are communicated with each other. (that is, the valve opens the internal passage). That is, the electromagnetic valve 64 selectively takes either the closed state or the open state. The negative pressure in the ink storage chamber 62a can be released by making the electromagnetic valve 64 open.

As a modification, the electromagnetic valve 64 may have a valve portion 64a connected outside the ink tank 61 so as to allow communication between the air communication passage 62e and the outside. In this way, it is possible to selectively take a communication state in which the atmosphere communication passage 62e communicates with the outside and a cutoff state in which communication with the outside is cut off. Alternatively, the entire electromagnetic valve 64 may be arranged in the ink storage chamber 62a. Further, the electromagnetic valve 64 is fixed to at least one of the front, rear, left, and right side walls of the tank body 62 other than the upper wall 62b, provided that the internal flow path of the valve portion 64a is connected to the atmosphere communication passage 62e so as to be able to communicate therewith. may be installed.

Further, the tank main body 62 is formed with an outlet 62h that penetrates the bottom wall 62g and allows the ink in the ink storage chamber 62a to flow out to the inkjet head 41. As shown in FIG. 62 h of outflow ports are the center of the left-right direction A3 of 62 g of bottom walls, and are arrange|positioned in the position near a front-end part.

<Inkjet head 41>
Black ink is supplied from an ink tank 61 to the inkjet head 41 . The inkjet head 41 also ejects ink from a plurality of nozzles 42 formed on a nozzle surface 41a (see FIG. 5), which is the lower surface. More specifically, as shown in FIG. 4, the plurality of nozzles 42 form a nozzle row extending in the front-rear direction A2 and along the transport direction of the paper P. As shown in FIG. Black ink is ejected from the plurality of nozzles 42 . The inkjet head 41 has a channel unit 43 and a piezoelectric actuator 50, as shown in FIGS.

<Flow path unit 43>
As shown in FIG. 5, the channel unit 43 is formed by stacking four plates 43a to 43d in order from the top. A plurality of nozzles 42 are formed in the plate 43d, as shown in FIGS. A plurality of pressure chambers 45 are formed in the plate 43a. Moreover, the pressure chamber 45 is provided for each nozzle 42, and the right end overlaps the nozzle 42 in the vertical direction A1.

As shown in FIGS. 4 and 5, the plate 43b is formed with a circular through hole 46a in a portion overlapping the left end of each pressure chamber 45 in the vertical direction A1. A circular through hole 46b is formed in the plate 43b in a portion overlapping the right end of each pressure chamber 45 and the nozzle 42 in the vertical direction A1.

A manifold channel 47 is formed in the plate 43c, as shown in FIGS. The manifold channel 47 extends in the front-rear direction A2 (conveyance direction) and overlaps the left portions of the plurality of pressure chambers 45 in the vertical direction A1. Thereby, each pressure chamber 45 communicates with the manifold channel 47 via the through hole 46a. Further, as shown in FIG. 4, a supply port 48 is provided at the downstream end of the manifold channel 47 in the transport direction. The supply port 48 opens to the upper surface of the channel unit 43 (that is, the upper surface of the plate 43a).

The inkjet head 41 is connected to the ink tank 61 via a connecting member 69 as shown in FIG. The connection member 69 is formed with a communicating passage 69a (“liquid flow path” of the present invention) that connects the outflow port 62h and the supply port 48 . As a result, the ink in the ink storage chamber 62 a of the ink tank 61 is supplied to the manifold channel 47 through the supply port 48 .

Further, as shown in FIGS. 4 and 5, the plate 43c is formed with a circular through hole 49 in a portion overlapping the through hole 46b and the nozzle 42 in the vertical direction A1. As a result, each nozzle 42 communicates with the pressure chamber 45 via the through holes 46b and 49. As shown in FIG.

In the channel unit 43, the nozzle 42, the pressure chamber 45, the through holes 46b and 49 connecting the nozzle 42 and the pressure chamber 45, and the through hole 46a connecting the pressure chamber 45 to the manifold channel 47 , individual channels 44 are formed. A plurality of individual flow paths 44 are formed corresponding to the plurality of nozzles 42 .

<Piezoelectric actuator 50>
The piezoelectric actuator 50 has a vibration plate 51, a piezoelectric layer 52, a common electrode 53, and a plurality of individual electrodes 54, as shown in FIG. The vibration plate 51 is made of a piezoelectric material containing lead zirconate titanate as a main component, is arranged on the upper surface of the channel unit 43 , and covers the plurality of pressure chambers 45 . Note that, unlike the piezoelectric layer 52, the vibration plate 51 may be made of an insulating material other than a piezoelectric material.

The piezoelectric layer 52 is made of a piezoelectric material and arranged on the upper surface of the diaphragm 51 . The piezoelectric layer 52 extends continuously over the plurality of pressure chambers 45, as shown in FIG. The common electrode 53 is arranged between the diaphragm 51 and the piezoelectric layer 52 and extends continuously across the plurality of pressure chambers 45, as shown in FIG. The common electrode 53 is connected to the power supply 6 via wiring members (FPC (Flexible Printed Circuits) 96, COF (Chip On Film) 95), etc., which will be described later, and is held at a ground potential. there is

The plurality of individual electrodes 54 individually correspond to the plurality of pressure chambers 45, as shown in FIG. The individual electrode 54 has an elliptical planar shape that is slightly smaller than the pressure chamber 45, is arranged on the upper surface of the piezoelectric layer 52, and overlaps the central portion of the pressure chamber 45 in the vertical direction A1. The left end of the individual electrode 54 extends to a position where it does not overlap the pressure chamber 45 in the vertical direction A1. The left end of the individual electrode 54 serves as a connection terminal 54a to which the COF 95, which will be described later, is connected. The individual electrodes 54 are connected to a driver IC 59 (see FIG. 8) mounted on the COF 95 . Then, the driver IC 59 selectively applies either the ground potential or a predetermined drive potential (for example, about 20 V) to each of the individual electrodes 54 .

Also, the portions sandwiched between the common electrode 53 and the individual electrodes 54 of the piezoelectric layer 52 are each polarized in the vertical direction A1. In the piezoelectric actuator 50 , the portions of the vibration plate 51 , the piezoelectric layer 52 and the common electrode 53 that vertically overlap the pressure chambers 45 and the portions formed by the individual electrodes 54 are in contact with the ink in the pressure chambers 45 . It is a drive element 55 that applies pressure.

Here, a method for driving the piezoelectric actuator 50 to eject ink from the nozzles 42 will be described. In the piezoelectric actuator 50, all individual electrodes 54 are held at the same ground potential as the common electrode 53 in advance. When ejecting ink from a certain nozzle 42, the potential of the individual electrode 54 in the drive element 55 corresponding to that nozzle 42 is switched from the ground potential to the drive potential. Then, due to the potential difference between the individual electrode 54 and the common electrode 53, the portions of the vibration plate 51 and the piezoelectric layer 52 overlapping the pressure chambers 45 in the vertical direction A1 are deformed so as to protrude toward the pressure chambers 45 as a whole. As a result, the volume of the pressure chamber 45 is reduced, the pressure of the ink in the pressure chamber 45 is increased, and the ink is ejected from the nozzle 42 communicating with the pressure chamber 45 .

<Platen 17>
The platen 17 is arranged below the inkjet head 41 and supports the paper P transported by the transport roller pair 35 . The platen 17 is arranged in a portion through which the paper P passes in the reciprocating range of the carriage 70 . Since the width of the platen 17 is sufficiently larger than the maximum width of the paper P that can be transported, the paper P transported along the transport path 25 always passes over the platen 17 .

<Moving mechanism 71>
The moving mechanism 71 includes a pair of guide rails 72 and a belt transmission mechanism (not shown), as shown in FIG. The pair of guide rails 72 are spaced apart in the front-rear direction A2 and extend parallel to each other in the left-right direction A3. The carriage 70 is arranged to straddle the pair of guide rails 72 . The carriage 70 is connected to a carriage motor 70M (see FIG. 8) via a belt transmission mechanism, and when the carriage motor 70M is driven, the belt transmission mechanism is driven. As a result, the carriage 70 moves along the pair of guide rails 72 in the scanning direction (horizontal direction A3) together with the ink tank 61 and the inkjet head 41 .

The inkjet head 41 ejects ink from the nozzles 42 under the control of the controller 5 based on the recording data. That is, as the carriage 70 reciprocates in the horizontal direction A<b>3 , the inkjet head 41 scans the paper P, and ink is ejected from the nozzles 42 . is recorded.

<Relay board 80>
As shown in FIG. 6, the relay board 80 is connected to the control board 7 (the "main board" of the present invention) on which the control unit 5 and the power supply 6 are mounted via an FFC (Flexible Flat Cable) 8. It is connected. As a result, the control signal generated by the control unit 5 and the voltage generated by the power supply 6 can be input to the relay board 80 via the FFC 8, as will be described in detail later. The relay board 80 and the control board 7 may be connected by FPC (Flexible Printed Circuits) or other connection members.

The relay board 80 is supported by the carriage 70, and is arranged behind the ink tank 61 while being erected along the vertical direction A1, as shown in FIG. 3B. The relay board 80 has a rectangular planar shape, as shown in FIG. The relay board 80 is provided with three connection portions 82 to 84, a voltage supply portion 90, and a signal wiring 88. As shown in FIG.

<Connections 82 to 84>
The connecting portion 82 is arranged near the center of the right end portion of the relay board 80, as shown in FIG. One end of the FFC 8 is connected to the connecting portion 82 . The connecting portion 83 is arranged near the center of the lower end portion of the relay board 80 . As shown in FIG. 3B, the connecting portion 83 is connected to the FPC 96 connected to the COF 95 connected to the piezoelectric actuator 50 of the inkjet head 41 . The connecting portion 84 is arranged near the center of the upper end portion of the relay substrate 80, as shown in FIG. A wire 97 connected to the electromagnetic valve 64 is connected to the connecting portion 84 as shown in FIG. 3B.

<Voltage supply unit 90>
The voltage supply unit 90 supplies the ink-jet head 41 and the electromagnetic valve 64 with a voltage input through a power supply line 8a of the FFC 8, which will be described later. As shown in FIG. 6, the voltage supply section 90 includes a power supply wiring 91 (the "wiring" of the present invention), a head wiring 91a (the "first branch wiring" of the present invention), and a valve wiring 91b (the "wiring" of the present invention). ("second branch wiring" of the present invention), a drive circuit 92, and a connection line 93 (a "second connection line" of the present invention).

One end of the power wiring 91 is connected to the connecting portion 82 . That is, the power supply wiring 91 is connected to the power supply line 8a of the FFC 8 connected to the connection portion 82 . The wiring 91a for the head and the wiring 91b for the valve are each formed by branching the end of the power supply wiring 91 opposite to the side connected to the connection portion 82 .

The head wiring 91 a is connected to the connection portion 83 at the end opposite to the power supply wiring 91 side. That is, the head wiring 91 a is connected to the inkjet head 41 via the connecting portion 83 , the FPC 96 and the COF 95 .

The valve wiring 91b is connected to the connection portion 84 at the end opposite to the power supply wiring 91 side. A drive circuit 92 is arranged in the middle of the valve wiring 91b. That is, the valve wiring 91 b is connected to the electromagnetic valve 64 via the drive circuit 92 , the connecting portion 84 and the wiring 97 .

The drive circuit 92 has a connection line 94 (the "first connection line" of the present invention), a capacitor 85, a switching circuit 86, and a diode 87, as shown in FIG.

A connection line 94 connects an intermediate point 94a on the valve wiring 91b and the ground. A capacitor 85 is provided on the connection line 94 . The capacitor 85 is charged by the voltage input to the valve wiring 91b through the power supply line 8a, the connecting portion 82 and the power supply wiring 91. As shown in FIG.

The switching circuit 86 is provided between the intermediate point 94a and the connecting portion 84 in the valve wiring 91b. A portion of the valve wiring 91b closer to the power source wiring 91 than the switching circuit 86 is referred to as a first portion 91b1, and a portion closer to the connecting portion 84 than the switching circuit 86 is referred to as a second portion 91b2. A connection line 93 connects an intermediate point 93 a on the head wiring 91 a and the switching circuit 86 . The configuration of the switching circuit 86 will be detailed later.

The diode 87 is provided between the power supply wiring 91 and the intermediate point 94a in the first portion 91b1 of the bulb wiring 91b. The diode 87 prevents the flow of electricity from the intermediate point 94a toward the power supply wiring 91. FIG.

The switching circuit 86 will now be described in more detail. The switching circuit 86 can switch between a state in which voltage is supplied to the electromagnetic valve 64 and a state in which voltage is not supplied to the electromagnetic valve 64 . The switching circuit 86 is a transistor or LDO (Low Drop Out).

The VDD terminal of the switching circuit 86 is connected to the end of the first portion 91b1 of the valve wiring 91b opposite to the end on the power supply wiring 91 side. The VOUT terminal of the switching circuit 86 is connected to the end of the second portion 91b2 of the valve wiring 91b opposite to the end on the connecting portion 84 side. The CE terminal of the switching circuit 86 is connected to the end of the connection line 93 opposite to the end on the intermediate point 93a side. A voltage generated by the power source 6 is input to the CE terminal of the switching circuit 86 via the power line 8 a of the FFC 8 , the power line 91 , the head line 91 a and the connection line 93 .

The switching circuit 86 functions as a transformer circuit that changes the voltage input via the VDD terminal to a magnitude (=V2) required to drive the electromagnetic valve 64 . Here, in the present embodiment, the power supply 6 generates a voltage (=V1) required to drive the inkjet head 41 . It is assumed that V1>V2. The switching circuit 86 steps down the voltage (=V1) input via the VDD terminal to V2. If V1<V2, the switching circuit 86 boosts the voltage (=V1) input via the VDD terminal to V2.

The switching circuit 86 switches to a state in which voltage is not supplied to the electromagnetic valve 64 when the voltage is generated by the power supply 6 and the voltage is input to the CE terminal. Further, the switching circuit 86 switches to a state in which the voltage is supplied to the electromagnetic valve 64 by discharging the capacitor 85 when the voltage is not generated by the power supply 6 and the voltage is not input to the CE terminal.

<Signal wiring 88>
Returning to FIG. 6, one end of the signal wiring 88 is connected to the connection portion 82 . The signal wiring 88 is connected to a signal line 8b of the FFC 8 connected to the connecting portion 82, which will be described later. The other end of the signal wiring 88 is connected to the connection portion 83 . That is, the signal wiring 88 is connected to the inkjet head 41 via the connecting portion 83 , FPC 96 and COF 95 .

<FFC8>
On the FFC 8, as shown in FIG. 6, a power supply line 8a and a signal line 8b are formed, each of which has one end connected to the connection portion 7a of the control board 7 and the other end connected to the connection portion 82 of the relay board 80. It is The other end of the power line 8 a is connected to the power line 91 via the connecting portion 82 . The other end of the signal line 8b is connected to the signal wiring 88 via the connecting portion 82 . The power supply line 8 a inputs the voltage generated by the power supply 6 to the voltage supply section 90 . The signal line 8 b transmits a control signal from the control section 5 to the inkjet head 41 .

<Control unit 5>
As shown in FIG. 8 , the control unit 5 has a CPU (Central Processing Unit) 131 , an ASIC (Application Specific Integrated Circuit) 135 and a memory 140 . These CPU 131, ASIC 135 and memory 140 are mounted on the control board 7 (see FIG. 6). As shown in FIG. 6, signal wirings 7b and 7c provided on the control board 7 are connected to the ASIC 135, respectively. The end of the signal wiring 7 b opposite to the ASIC 135 side is connected to the power supply 6 . The end of the signal wiring 7 c opposite to the ASIC 135 side is connected to the connection portion 7 a of the control board 7 .

Returning to FIG. 8, the CPU 131 , ASIC 135 and memory 140 are connected by an internal bus 137 . The memory 140 includes ROM (Read Only Memory) 132 , RAM (Random Access Memory) 133 and EEPROM (Electrically Erasable Programmable Read-Only Memory) 134 . The ROM 132 stores programs and the like for controlling various operations of the printer 1 . The CPU 131 executes programs using the RAM 133 and EEPROM 134 . At least one of the CPU 131 and the memory 140 may be provided separately without being mounted on the control board 7 .

The ASIC 135 outputs control signals to the ASF motor 20M, the LF motor 30M, the carriage motor 70M, the inkjet head 41, the power supply 6, etc., and controls their operations. For example, the control unit 5 controls the inkjet head 41, the ASF motor 20M, the LF motor 30M, the carriage motor 70M, etc., based on recording data transmitted from an external device (for example, a PC or a smartphone) to perform transport processing and recording. processing are alternately executed, and an image or the like is recorded on the paper P. Also, the control unit 5 controls on/off of the power source 6 . For example, the control unit 5 controls on/off of the power supply 6 for each recording job. That is, the control unit 5 turns on the power supply 6 while the images for one recording job are being recorded, and turns off the power supply 6 when the recording of the images for one recording job is completed.

The ASIC 135 in this embodiment is connected to the ASF motor 20M, the LF motor 30M, and the carriage motor 70M by individual wiring (not shown), and controls these motors 20M, 30M, and 70M.

Note that the control unit 5 of the present embodiment has one CPU and one ASIC, but the control unit 5 includes only one ASIC, and this one ASIC collectively performs necessary processing. , or may include a plurality of ASICs, and the plurality of ASICs may share the required processing.

<Power supply 6>
The power supply 6 is mounted on the control board 7, as shown in FIG. The power supply 6 is a regulator or the like, and generates a voltage required to drive the inkjet head 41 from the voltage supplied from the external power supply. The power supply 6 is connected to the ASIC 135 of the control section 5 by signal wiring 7b. Also, the power source 6 is connected to the other end of the power wiring 7d, one end of which is connected to the connecting portion 7a. That is, the power supply 6 is connected to the power supply line 8a of the FFC 8 via the power supply wiring 7d and the connection portion 7a. The end of the power line 8 a opposite to the side connected to the power supply 6 is connected to the power line 91 via the connecting portion 82 .

<Operation of Voltage Supply Unit 90>
Here, the operation of the voltage supply section 90 will be described with reference to FIG. When the power supply 6 is turned on under the control of the control unit 5, the voltage generated by the power supply 6 is supplied to the voltage supply unit 90 through the connection unit 82 of the relay board 80, as shown in FIG. is input to the power supply wiring 91 of . A voltage input to the power supply wiring 91 is supplied to the head wiring 91a and the valve wiring 91b.

The voltage supplied to the wiring 91 a for the head is supplied to the inkjet head 41 via the connecting portion 83 of the relay substrate 80 . Also, the voltage supplied to the head wiring 91 a is input to the CE terminal of the switching circuit 86 via the connection line 93 . By inputting the voltage to the CE terminal, the switching circuit 86 enters a state in which no voltage is supplied to the electromagnetic valve 64 .

On the other hand, the capacitor 85 is charged with the voltage supplied to the valve wiring 91b. As described above, at this time, the switching circuit 86 is in a state where no voltage is supplied to the electromagnetic valve 64, so that the voltage supplied to the valve wiring 91b is supplied to the electromagnetic valve 64 via the connecting portion 84. no.

When the power supply 6 is turned off under the control of the control unit 5, the voltage input from the power supply 6 stops and the capacitor 85 discharges as shown in FIG. 7(b). At this time, the diode 87 prevents the flow of electricity from the intermediate point 94 a toward the power supply wiring 91 . Also, since no voltage is input to the CE terminal of the switching circuit 86 , the switching circuit 86 is in a state in which voltage is supplied to the electromagnetic valve 64 by discharging the capacitor 85 . Therefore, the voltage is supplied to the electromagnetic valve 64 via the connecting portion 84 by the discharge of the capacitor 85 .

Thus, the voltage supply unit 90 can switch the supply destination of the voltage generated by the power supply 6 . Specifically, the voltage supply unit 90 supplies voltage to the inkjet head 41 when the power supply 6 is on, and supplies voltage to the electromagnetic valve 64 when the power supply 6 is off. The voltage supply unit 90 exclusively switches the voltage supply destination. That is, voltage is not supplied to both the inkjet head 41 and the electromagnetic valve 64 by the voltage supply unit 90 at the same time.

<Characteristics of the first embodiment>
As described above, the printer 1 of the above-described embodiment includes the power source 6 that generates voltage, the power line 8a connected to the power source 6, and the voltage generated by the power source 6 and input via the power line 8a. A voltage supply unit 90 that supplies voltage to the head 41 and the electromagnetic valve 64 is provided, and the voltage supply unit 90 can switch the voltage supply destination.

According to the above configuration, the voltage generated by one power supply 6 and input to the voltage supply section 90 via one power supply line 8 a can be supplied to the inkjet head 41 and the electromagnetic valve 64 . Therefore, the number of power sources 6 and the number of power lines 8a can be reduced, so that the size of the device can be reduced.

Further, the printer 1 of the above-described embodiment further includes a control board 7 on which the power source 6 is mounted, and a relay board 80 to which the inkjet head 41 and the electromagnetic valve 64 are connected. It is formed in In this embodiment, the number of power supplies 6 and the number of power supply lines 8a can be reduced, and the size of the control board 7 and the width of the FFC 8 can be reduced.

Furthermore, in the printer 1 of the above-described embodiment, the voltage supply section 90 is formed by branching the power supply wiring 91 connected to the power supply 6 of the power supply line 8a and the power supply wiring 91, respectively. The connected head wiring 91a and the valve wiring 91b connected to the electromagnetic valve 64, the connection line 94 connecting the intermediate point 94a of the valve wiring 91b and the ground, and the capacitor 85 provided in the connection line 94. , a switching circuit 86 provided in the wiring 91b for the valve and capable of switching between a state in which the voltage is supplied to the electromagnetic valve 64 and a state in which the voltage is not supplied to the electromagnetic valve 64; and a connection line 93 for connecting the . The switching circuit 86 generates a voltage by the power source 6 , and when the voltage is input to the switching circuit 86 via the connection line 93 , the switching circuit 86 switches to a state in which no voltage is supplied to the electromagnetic valve 64 , and the voltage is switched by the power source 6 . is not generated and no voltage is input to the switching circuit 86 through the connection line 93 , the discharge of the capacitor 85 switches to a state in which voltage is supplied to the electromagnetic valve 64 . Therefore, since the voltage supply section 90 does not require a control signal for switching the voltage supply destination, a signal line for supplying the control signal is not required, and the device can be further miniaturized.

In addition, in the printer 1 of the above-described embodiment, a diode 87 is provided between the power supply wiring 91 and the intermediate point 94a in the valve wiring 91b to prevent the flow of electricity from the intermediate point 94a toward the power supply wiring 91 side. It is Therefore, when the capacitor 85 is discharged, the supply of voltage to the ink jet head 41 can be prevented by the electricity flowing through the valve wiring 91b from the intermediate point 94a toward the power supply wiring 91 side.

Further, in the printer 1 of the above-described embodiment, the power supply 6 generates a voltage required to drive the inkjet head 41, and the switching circuit 86 of the voltage supply section 90 receives the input through the power supply line 8a. It functions as a transformer circuit that changes the applied voltage to the magnitude required to drive the electromagnetic valve 64 . Therefore, the electromagnetic valve 64 can be supplied with an appropriate voltage.

(Second embodiment)
Next, a printer according to a second embodiment of the invention will be described with reference to FIG. The main difference between the printer of this embodiment and the printer 1 of the first embodiment is the configuration of the voltage supply section 290 provided on the relay board 280 . Components having the same configuration as in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

The control board 207 of this embodiment is provided with two signal wirings 7c1 and 7c2, one end of which is connected to the ASIC 135 and the other end of which is connected to the connecting portion 7a. On the FFC 208, a power supply line 8a and two signal lines 8b1 and 8b2 are provided, each of which has one end connected to the connection portion 7a of the control board 7 and the other end connected to the connection portion 82 of the relay board 80. It is The signal line 8b1 is connected to the signal wiring 7c1 through the connection portion 7a of the control board 207. As shown in FIG. The signal line 8b2 is connected to the signal wiring 7c2 through the connection portion 7a of the control board 207. As shown in FIG. The signal line 8 b 2 is connected to the other end of the signal wiring 88 of which one end is connected to the connecting portion 83 on the relay board 280 .

The voltage supply section 290 has a switching circuit 286 mounted on the relay board 280 . The switching circuit 286 switches the supply destination of the input voltage between the inkjet head 41 and the electromagnetic valve 64 . The switching circuit 286 exclusively switches the voltage supply destination. Moreover, the switching circuit 286 has a function as a transformer circuit.

The switching circuit 286 is connected to the other end of the power wiring 291 , one end of which is connected to the connection portion 82 . The power wiring 291 is connected to the power line 8a of the FFC 8 connected to the connecting portion 82 . As a result, the voltage generated by the power supply 6 is input to the switching circuit 286 through the power supply wiring 7 d , the power supply wiring 8 a , the connection section 82 and the power supply wiring 291 .

Also, the switching circuit 286 is connected to the other end of the signal wiring 289 , one end of which is connected to the connection portion 82 . The signal wiring 289 is connected to the signal line 8b1 of the FFC 208 connected to the connecting portion 82. FIG. As a result, the control signal generated by the ASIC 135 is input to the switching circuit 286 via the signal wiring 7c1, the signal wiring 8b1, the connecting portion 82, and the signal wiring 289. FIG.

The switching circuit 286 is connected to the other end of the wiring 291 a for the head, one end of which is connected to the connecting portion 83 . The head wiring 291 a is connected to the inkjet head 41 via the connecting portion 83 , the FPC 96 and the COF 95 . The switching circuit 286 is connected to the other end of the wiring 291b for valve, one end of which is connected to the connecting portion 84 . The wiring 291 b for valve is connected to the electromagnetic valve 64 via the connecting portion 84 and the wiring 97 .

The ASIC 135 generates, as one of the control signals, a switching signal that instructs the switching circuit 286 to switch the voltage supply destination. The switching signal is a signal that instructs switching of the voltage supply destination to either the inkjet head 41 or the electromagnetic valve 64 . For example, the switching signal instructs to switch the supply destination of the voltage to the inkjet head 41 while the image for one print job is being printed, and when the image for one print job is finished printing the voltage. is instructed to switch the supply destination of the electric current to the electromagnetic valve 64. In the first embodiment, an example in which the power supply 6 is turned on/off for each recording job by the control unit 5 has been described. It is turned on continuously.

A voltage generated by the power supply 6 is input to the switching circuit 286 through the power supply line 8a. A switching signal generated by the ASIC 135 is input to the switching circuit 286 via the signal line 8b1. The switching circuit 286 switches the voltage supply destination based on the switching signal.

<Characteristics of Second Embodiment>
As described above, in the present embodiment, as in the first embodiment described above, the voltage generated by one power supply 6 and input to the voltage supply section 290 via one power supply line 8a is applied to the ink jet printer. Since it can be supplied to the head 41 and the electromagnetic valve 64, the size of the device can be reduced.

Further, in this embodiment, the ASIC 135 mounted on the control board 207 and the signal line 8b1 connected to the ASIC 135 are provided. The voltage supply unit 290 is mounted on the relay board 280, receives a voltage through the power line 8a, and has a switching circuit 286 that switches the voltage supply destination between the inkjet head 41 and the electromagnetic valve 64. are doing. The ASIC 135 generates a switching signal that instructs the switching circuit 286 to switch the voltage supply destination. The switching circuit 286 switches the voltage supply destination based on the switching signal generated by the ASIC 135 and input via the signal line 8b1. In this embodiment, although the signal line 8b1 for supplying the switching signal is necessary, the power supply line for supplying the voltage is thicker than the signal line. Miniaturization is possible.

Although the embodiments of the present invention have been described above with reference to the drawings, it should be considered that the specific configuration is not limited to these embodiments. The scope of the present invention is indicated by the scope of the claims rather than the description of the above-described embodiments, and includes all modifications within the meaning and scope equivalent to the scope of the claims.

In addition, in the above-described first and second embodiments, the power supply line 8a constitutes wiring formed in one FFC 8 (208), but the power supply line 8a itself is one individual wiring. good too.

Further, in the above-described first and second embodiments, voltage is supplied to the inkjet head 41 while the image for one print job is being printed, and the printing of the image for one print job is completed. Then, the case where the voltage is supplied to the electromagnetic valve 64 has been described, but the switching timing of the voltage supply destination is not limited to this. That is, for example, a negative pressure detection unit is provided to detect the negative pressure in the ink reservoir 62a, and when the negative pressure in the ink reservoir 62a is less than a predetermined value, voltage is supplied to the ink jet head 41, and the ink reservoir is detected. Voltage may be supplied to the electromagnetic valve 64 when the negative pressure in 62a reaches a predetermined value or higher.

Furthermore, in the above-described first and second embodiments, the case where the voltage supply unit 90 (290) exclusively switches the voltage supply destination has been described, but the present invention is not limited to this. That is, for example, the voltage supply unit 90 (290) may switch the voltage supply destination between only the inkjet head 41 and both the inkjet head 41 and the electromagnetic valve 64. FIG.

In addition, in the first and second embodiments described above, the case where the switching circuit 86 (286) functions as a transformer circuit has been described, but the present invention is not limited to this. A transformer circuit may be provided separately from the switching circuit 86 (286). Also, if the voltage (=V2) required to drive the electromagnetic valve 64 is equal to the voltage (=V1) required to drive the inkjet head 41, it corresponds to a transformer circuit. You don't have to be prepared.

Furthermore, in the first embodiment described above, the diode 87 is provided to prevent the reverse flow of electricity when the capacitor 85 is discharged, but the diode 87 may be omitted.

Additionally, although the embodiments described above employ the present invention in monochrome printers, the present invention may also be employed in color printers.

In the above-described embodiment, the ink tank 61 is provided with the ink inlet 67 for communication between the ink tank 61 and the outside, but the ink tank 61 is not provided with the ink inlet 67. It doesn't have to be.

In addition, in the above-described embodiment, the case where the ink tank 61 is provided with the electromagnetic valve 64 has been described, but the present invention is not limited to this. That is, the valve provided in the ink tank 61 may be an electrically driven valve. For example, instead of the electromagnetic valve 64, an electric valve driven by a motor may be employed.

Furthermore, in the above-described embodiment, the ink tank 61 and the inkjet head 41 are of the on-carriage type mounted on the carriage 70, but the present invention is not limited to this. That is, the present invention can also be applied to a line-type inkjet head in which the carriage 70 is not provided and the inkjet head is fixed.

The present invention can also be applied to a liquid ejection apparatus having a liquid ejection head that ejects liquid other than ink. Furthermore, the ejection target is not limited to the paper P, and may be, for example, a cloth, a substrate, or the like. Further, if it is possible to eject the liquid from the nozzles by being driven based on the signal from the control section 5, it is possible to adopt an ejection energy imparting means other than the piezoelectric actuator 50. FIG. In this case, for example, a thermal type ejection energy imparting means may be employed that heats the liquid ink in the nozzle with a heating element to generate bubbles and push the ink out of the nozzle for recording.

1 Printer (liquid ejection device)
5 control unit 6 power supply 7 control board (main board)
8 FFC (flexible cable)
8a Power line 8b1 Signal line 35 Conveying roller pair (conveying mechanism)
41 inkjet head (liquid ejection head)
61 ink tank (liquid reservoir)
62a Ink storage chamber (liquid storage chamber)
62e atmosphere communication passage 64 electromagnetic valve (valve)
69a communication path (liquid flow path)
70 Carriage 71 Moving Mechanism 80 Relay Board (Sub Board)
85 capacitor 86 switching circuit (transformation circuit)
87 diode 90 voltage supply unit (supply unit)
91 Power supply wiring (wiring)
91a Head wiring (first branch wiring)
91b Valve wiring (second branch wiring)
93 connection line (second connection line)
94 connection line (first connection line)
94a Intermediate point 135 ASIC (control unit)
286 switching circuit

Claims (8)

a liquid ejection head having nozzles for ejecting liquid;
A liquid storage chamber for storing liquid, an air communication passage for communicating the liquid storage chamber with the outside, and one of a communication state in which the air communication passage is communicated and a cutoff state in which the air communication passage is cut off. a liquid reservoir having an electrically actuated valve selectively removable;
a liquid flow path connecting the liquid ejection head and the liquid storage chamber so that the liquid can flow;
a power supply that generates a voltage;
a power line connected to the power source;
a supply unit that supplies a voltage generated by the power supply and input through the power supply line to the liquid ejection head and the valve,
The liquid ejecting apparatus, wherein the supply unit is capable of switching a voltage supply destination. a main board on which the power supply is mounted;
a sub-board to which the liquid ejection head and the valve are connected,
2. A liquid ejecting apparatus according to claim 1, wherein said power line is formed on a flexible cable. a control unit mounted on the main substrate;
a signal line connected to the control unit,
The supply unit is mounted on the sub-board, receives a voltage through the power supply line, and has a switching circuit that switches a voltage supply destination between the liquid ejection head and the valve. cage,
The control unit generates a switching signal that instructs the switching circuit to switch a voltage supply destination,
3. The liquid ejecting apparatus according to claim 2, wherein the switching circuit switches the voltage supply destination based on the switching signal generated by the control section and input via the signal line. The supply unit is
a wiring connected to an end of the power supply line opposite to the side connected to the power supply;
a first branched wiring connected to the liquid ejection head and a second branched wiring connected to the valve, each formed by branching the wiring;
a first connection line connecting an intermediate point on the second branch wiring and the ground;
a capacitor provided on the first connection line and charged by the voltage input to the second branch wiring via the power supply line;
a switching circuit provided between the intermediate point of the second branch wiring and the valve, and capable of switching between a state in which voltage is supplied to the valve and a state in which voltage is not supplied to the valve;
a second connection line that connects the first branch wiring and the switching circuit;
The switching circuit is
A voltage is generated by the power supply, and when voltage is input to the switching circuit via the power supply line, the wiring, the first branch wiring, and the second connection line, the voltage is supplied to the valve. switch to not
When no voltage is generated by the power supply and no voltage is input to the switching circuit via the power supply line, the wiring, the first branch wiring and the second connection line, the discharge of the capacitor 3. The liquid ejecting apparatus according to claim 1, wherein the valve is switched to a state in which a voltage is supplied. 5. The liquid ejecting apparatus according to claim 4, wherein a diode is provided between the wiring and the intermediate point of the second branch wiring to prevent the flow of electricity from the intermediate point toward the wiring. the power supply generates a voltage required to drive the liquid ejection head;
6. The supply unit according to any one of claims 1 to 5, wherein the supply unit has a transformer circuit that changes the voltage input through the power supply line to a magnitude necessary to drive the valve. 2. The liquid ejection device according to item 1. a transport mechanism for transporting a recording medium in a transport direction;
a carriage that supports the liquid ejection head and the liquid reservoir;
7. The liquid ejecting apparatus according to claim 1, further comprising a moving mechanism for moving the carriage in a scanning direction that intersects with the transport direction. 8. The liquid ejecting apparatus according to claim 1, wherein the valve is an electromagnetic valve.

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