JP6458928B2 - Liquid ejection head, liquid ejection apparatus, and liquid ejection head control method - Google Patents

Description

  The present invention relates to a liquid ejection head, a liquid ejection apparatus, and a method for controlling a liquid ejection head, and more particularly to a case where a flow path opening / closing means and a flow path pressure adjusting means are provided in a liquid flow path of a liquid ejection head from a liquid supply source It is useful to apply.

  A typical example of a liquid discharge head that discharges droplets is an ink jet recording head that discharges ink droplets. As the ink jet recording head, for example, a head main body that ejects ink droplets from nozzle openings and a head main body are fixed, and ink is supplied from an ink cartridge that stores ink, and ink from the ink cartridge is discharged. And a flow path member that is supplied to the head body. In this type of ink jet recording head, the back pressure in the head (reservoir or pressure chamber) is normally maintained at a negative pressure in order to manage the meniscus position at a position corresponding to continuous ejection. However, there is a possibility that bubbles near the nozzle opening may be drawn into the nozzle opening due to the negative pressure during wiping. If air bubbles are drawn into the nozzle opening, nozzle clogging may occur.

  Therefore, it is necessary to release the negative pressure when necessary during wiping. For this reason, an eccentric cam as a pressurizing mechanism is provided beside the flow path between the negative pressure generating means (differential pressure valve) and the head, and the inside of the head is pressurized by the pressurizing mechanism via the eccentric cam during wiping. Has been proposed (see Patent Document 1). In addition, there is a configuration in which a bypass flow path for pressurization supply is provided and pressurization by a pressurization pump is performed directly in the head (see Patent Document 2).

JP 2013-161827 A JP 2011-161844 A

  However, since Patent Document 1 changes the volume of the flow path by abutment of the eccentric cam with respect to the tube, for example, when the number of nozzles increases, for example, when the number of nozzles increases, the required volume changes. It is hard to cause. On the other hand, when trying to obtain a large volume change by thickening the tube, the flow rate is lowered by the amount of the thickening of the tube, and the exhaustability is deteriorated.

  In Patent Document 2, it is difficult to finely adjust the amount of liquid to be supplied, and a lot of fluid may be wasted.

  Further, with wiping or the like, it may be difficult to once release the negative pressure and form an appropriate meniscus in the nozzle opening again after the wiping operation is completed.

  Such a problem exists not only in a flow path member used for a liquid discharge head such as an ink jet recording head but also in a flow path member used in a device other than the liquid discharge head.

  In view of the circumstances as described above, the present invention not only can reduce the volume of the flow path to be released when releasing the negative pressure to easily and effectively release the negative pressure, but also returns to the normal state after releasing the negative pressure. An object of the present invention is to provide a liquid discharge head, a liquid discharge apparatus, and a method for controlling the liquid discharge head that can smoothly perform the recovery.

An aspect of the present invention that solves the above problem is a liquid discharge head including a discharge unit that discharges liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving a drive element. The negative pressure generating means that communicates with the discharge section and maintains the negative pressure of the discharge section, and is in the middle of the flow path between the negative pressure generation means and the discharge section, and changes the volume of the flow path. A pressure adjusting means for adjusting the pressure in the flow path, and a flow opening / closing means for opening and closing the flow path in the middle of the flow path between the negative pressure generating means and the pressure adjusting means in the flow path. When the inside of the flow path is pressurized by the pressure adjusting means in the flow path, the flow path is closed by the flow path opening / closing means prior to pressurization, and the pressure adjusting means in the flow path is used. When the inside of the flow path is pressurized, after the flow path is opened by the flow path opening / closing means, A liquid discharge head characterized by reduced pressure in the flow path by the flow path in the pressure regulating means.
In this aspect, the meniscus of the nozzle opening can be easily and appropriately formed when the liquid discharge head returns to the normal operation after the negative pressure is released. That is, the flow path pressure adjusting means can be used effectively.
Here, the volume of the pressure adjusting means in the flow path is preferably larger than the volume of the flow path opening / closing means. According to this, since the volume change amount for pressure adjustment can be increased as the volume is increased, the pressure adjusting means in the flow path can be effectively used.
Further, the volume of the pressure adjusting means in the flow path and the volume of the flow path opening / closing means are adjusted by the amount of displacement of the flexible member respectively included in the pressure adjusting means in the flow path and the flow path opening / closing means, Moreover, it is preferable that the amount of displacement of the flexible member included in the pressure adjusting means in the flow path is larger than the amount of displacement of the flexible member included in the flow path opening / closing means. According to this, since the volume change amount for pressure adjustment can be increased as the displacement amount of the flexible member is increased, the pressure adjusting means in the flow path can be effectively used.
The negative pressure generating means includes a flexible member that is displaced by the negative pressure, and the flexible member included in the negative pressure generating means is more easily bent than the flexible member included in the flow path pressure adjusting means. It is preferable to be configured. According to this, as the flexible member of the negative pressure generating means is more easily bent, the pressure fluctuation at the time of closing the flow path can be absorbed by the flexible member of the negative pressure generating means. This is because fluctuations need not be taken into account and the pressure adjusting means in the flow path can be used effectively.
The flow path opening / closing means communicates with the third recess that communicates with the discharge section and stores the liquid, and a fluid supply source that supplies the fluid that operates the flow path opening / closing means, and stores the fluid. A fourth recess facing the third recess, and a second flexible member interposed between the third recess and the fourth recess to seal the third recess and the fourth recess. And the volume of the fourth recess is preferably smaller than that of the third recess. According to this, since the volume of the 4th crevice is small, the change of the channel volume accompanying opening and closing can be made small. In particular, in order to prevent the second flexible member from closing the flow path due to the negative suction pressure when the flow path is closed by the flow path opening / closing means provided on the supply side, The inside of the recess may be depressurized and the second flexible member may be brought into contact with the third recess. That is, there is a case where suction is performed in a contact state, but even in this case, if the volume of the fourth recess is small, the flow volume between the pressure reduction in the third recess and the release thereof is reduced. Variation can be reduced.
Moreover, it is preferable that a said 4th recessed part has a convex part in the position contact | abutted with a said 2nd flexible member. According to this, since the position of the second flexible member can be regulated by bringing the second flexible member into contact with the convex portion, the second flexible member of the fourth concave portion at the normal time and during the decompression can be controlled. This is because the positions can be the same.
Further, there are a plurality of sets of the pressure adjusting means in the flow path, the flow path opening / closing means, and the discharge unit, and a plurality of fluids that drive the pressure adjusting means in the flow path are supplied from a common fluid supply source. It is preferable to adjust the pressure in each of the flow paths by all the sets of in-flow path pressure adjusting means by supplying the set to the in-flow path pressure adjusting means . According to this , a structure can be simplified in comparison with the structure provided with the fluid supply source for every negative pressure cancellation | release mechanism .
Et al is, another aspect of the present invention, there is provided a liquid ejecting apparatus that comprises the above-mentioned liquid discharge head.
In this mode, not only can the volume of the flow path to be released when releasing the negative pressure associated with the wiping operation be reduced to easily and effectively release the negative pressure, but also the normal state after the negative pressure is released can be restored. It can be done smoothly.
Here, after wiping the nozzle surface of the discharge portion of the liquid discharge head, the control means for opening the flow path by the flow path opening / closing means and controlling the pressure in the flow path to depressurize the flow path It is preferable to have. This is because the predetermined operation can be performed sequentially when returning to the normal operation after releasing the negative pressure.
Furthermore, another aspect of the present invention is a liquid ejection apparatus including a ejection unit that ejects a liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving a drive element. The flow path of the first flow path opening / closing means provided in the middle of the flow path between the liquid supply source and the discharge section, and opening / closing the flow path, the liquid supply source, and the first flow path opening / closing means. A second flow path opening / closing means that opens and closes the flow path, and a suction means that sucks the liquid in the flow path from the discharge portion, and the flow path is opened by the first flow path opening / closing means. In a state where the channel is opened and the channel is closed by the second channel opening and closing unit, the first mode of suction by the suction unit, and the channel is closed by the first channel opening and closing unit, The second mode in which suction is performed by the suction means is performed, and the second mode is performed. After the operation mode, a liquid discharging apparatus characterized by performing the operation of the second mode.
In such an embodiment, each mode of suction can be performed at a desired timing. As a result, wasteful disposal of the liquid accompanying the suction operation can be reduced as much as possible by appropriately performing not only the suction during the initial filling but also the air exhaust during the printing operation after the initial filling.
Further, by performing the second mode operation after the first mode operation, it is possible to improve the exhaustability at the time of initial filling.
Further, it is preferable that the frequency of performing the operation of the second mode is higher than the frequency of performing the first mode. According to this, since the liquid consumption is smaller in the second mode, effective bubble discharge can be performed.
In the first mode operation, it is preferable that the first channel opening / closing means keeps the channel open. According to this, for example, in the concave portion filled with fluid of the flow path opening / closing means, when any of air release, decompression, and pressurization can be performed, if the decompression is performed when suctioning the ejection unit, the ejection unit It is possible to prevent the elastic member from unintentionally closing the flow path due to the suction from.
Furthermore, another aspect of the present invention is a liquid discharge head including a discharge unit that discharges liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element, The negative pressure generating means that communicates with the discharge section and maintains the negative pressure of the discharge section, and is in the middle of the flow path between the negative pressure generation means and the discharge section, and the volume of the flow path is changed, A pressure adjusting means for adjusting the pressure in the flow path; a flow opening / closing means for opening and closing the flow path, which is in the middle of the flow path between the negative pressure generating means and the pressure adjusting means in the flow path; A first step of pressurizing the inside of the flow path by the pressure adjusting means in the flow path after closing the flow path by the flow path opening and closing means, and the inside of the flow path When the inside of the flow path is pressurized by the pressure adjusting means, the flow path opening / closing means After opening the serial channel, the control method of the liquid discharge head is characterized in that a second step for reducing the pressure of the flow channel by the flow channel pressure regulating means.
In this aspect, the meniscus of the nozzle opening can be formed easily and appropriately when the liquid discharge head is restored to the normal operation after the negative pressure is released.
Another aspect is a liquid discharge head including a discharge unit that discharges liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element. A negative pressure generating means that communicates and maintains the negative pressure of the discharge section; and is in the middle of the flow path between the negative pressure generation means and the discharge section; A pressure adjusting means for adjusting the internal pressure of the flow path, and a flow path opening / closing means for opening and closing the flow path in the middle of the flow path between the negative pressure generating means and the pressure adjusting means in the flow path. When the inside of the channel is pressurized by the in-channel pressure adjusting means, the inside of the channel is decompressed by the in-channel pressure adjusting means after the channel is opened by the channel opening / closing means. In the liquid discharge head.
According to this aspect, the meniscus of the nozzle opening can be formed easily and appropriately when the liquid discharge head returns to the normal operation after the negative pressure is released. That is, the flow path pressure adjusting means can be used effectively.

In here, the volume of the pre-Symbol passage pressure adjusting means, than the volume of the flow path opening and closing means is preferably larger. This is because the volume change amount for pressure adjustment can be increased as the volume is increased, so that the pressure adjusting means in the flow path can be effectively used.

Further, the volume of the pressure adjusting means in the flow path and the volume of the flow path opening / closing means are adjusted by the amount of displacement of the flexible member respectively included in the pressure adjusting means in the flow path and the flow path opening / closing means, Moreover, it is desirable that the amount of displacement of the flexible member included in the flow path pressure adjusting unit is larger than the amount of displacement of the flexible member included in the channel opening / closing unit. This is because the volume change amount for pressure adjustment can be increased as the displacement amount of the flexible member is increased, so that the pressure adjusting means in the flow path can be effectively used.

The negative pressure generating means includes a flexible member that is displaced by the negative pressure, and the flexible member included in the negative pressure generating means is more easily bent than the flexible member included in the flow path pressure adjusting means. It is desirable to be configured. The more flexible the flexible member of the negative pressure generating means is, the more the pressure fluctuation when closing the flow path can be absorbed by the flexible member of the negative pressure generating means. Therefore, the pressure adjusting means in the flow path does not consider the pressure fluctuation. This is because the pressure adjusting means in the flow path can be used effectively.

The flow path opening / closing means communicates with the third recess that communicates with the discharge section and stores the liquid, and a fluid supply source that supplies the fluid that operates the flow path opening / closing means, and stores the fluid. A fourth recess facing the third recess, and a second flexible member interposed between the third recess and the fourth recess to seal the third recess and the fourth recess. And the volume of the fourth recess is preferably smaller than that of the third recess . According to this, since the volume of the 4th crevice is small, the change of the channel volume accompanying opening and closing can be made small. In particular, in order to prevent the second flexible member from closing the flow path due to the negative suction pressure when the flow path is closed by the flow path opening / closing means provided on the supply side, The inside of the recess may be depressurized and the second flexible member may be brought into contact with the third recess. That is, there is a case where suction is performed in a contact state, but even in this case, if the volume of the fourth recess is small, the flow volume between the pressure reduction in the third recess and the release thereof is reduced. Variation can be reduced.

In here, before Symbol fourth recess, in a position in which it contacts the second flexible member, it is desirable to have a protrusion. Since the position of the second flexible member can be regulated by bringing the second flexible member into contact with the convex portion, the position of the second flexible member in the fourth concave portion at the time of decompression is made the same as in the normal time. Because it can.

Another aspect of the present invention is a liquid discharge head including a discharge unit that discharges a liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element. In the middle of the flow path of the flow path pressure adjusting means for adjusting the pressure in the flow path by changing the volume of the flow path, and the liquid supply source and the pressure adjustment means in the flow path A flow path opening / closing means for opening and closing the flow path, wherein there are a plurality of sets of the pressure adjusting means in the flow path, the flow path opening / closing means, and the discharge section, and a plurality of sets of the pressure adjustments in the flow path. The fluid for driving the means is supplied from a common fluid supply source to the plurality of sets of pressure adjusting means in the flow path, so that all the sets of pressure adjustment means in the flow path can adjust the flow in the flow paths. In the liquid discharge head, the pressure of the liquid is adjusted.
According to this aspect, the configuration can be simplified in comparison with the configuration including the fluid supply source for each negative pressure release mechanism.

In here, when adjusting the pressure of each of the flow channel by a set of the flow channel pressure regulating means all hands, from the discharge portion of the entire set, of the volume by the flow channel pressure regulating means It is desirable that liquid be ejected due to the change. Even if the volume required to release the negative pressure (hereinafter also referred to as “excluded volume”) differs depending on the negative pressure release mechanism or the corresponding head, it is possible to discharge the liquid from the negative pressure release mechanism or head that requires a small excluded volume. To the extent that negative pressure can be reliably released to all negative pressure release mechanisms and heads while allowing, the excluded volume can be reliably formed, and negative pressure can be reliably released. Because.

In here, when adjusting the pressure of each of the flow channel by all hand set in the channel pressure regulating means, cause opposed to the discharge unit relative to the cap member for capping the liquid discharge head Is desirable. When releasing the negative pressure, a cap may be disposed under the head as a measure for allowing the liquid to be discharged. Thereby, even if a liquid is discharged, a main body etc. are not polluted.

Another aspect of the present invention is a liquid discharge apparatus including the above-described liquid discharge head.
According to this aspect, not only can the volume of the flow path to be released when releasing the negative pressure associated with the wiping operation or the like be reduced to easily and effectively release the negative pressure, but also to the normal state after the negative pressure is released. Recovery can also be performed smoothly.

In here, the nozzle surface of the ejection portion prior Symbol liquid ejection head is opened to the flow path by the flow path opening and closing means after wiping, and controls so as to reduce the pressure of the flow channel by the flow channel pressure regulating means It is desirable to have a control means. This is because a predetermined operation can be performed sequentially when returning to the normal operation after releasing the negative pressure.

Another aspect of the present invention is a liquid discharge apparatus including a discharge unit that discharges a liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving a drive element. The middle of the flow path of the first flow path opening / closing means, the liquid supply source, and the first flow path opening / closing means provided in the middle of the flow path between the source and the discharge unit. A second flow path opening / closing means for opening and closing the flow path, and a suction means for sucking the liquid in the flow path from the discharge portion, and the flow path is opened by the first flow path opening / closing means. A first mode in which suction is performed by the suction means while the flow path is closed by the second flow path opening / closing means; and the suction means is closed by the first flow path opening / closing means. And the second mode of sucking in, respectively. In the body ejection device.
According to this aspect, each mode of suction can be performed at a desired timing. As a result, wasteful disposal of the liquid accompanying the suction operation can be reduced as much as possible by appropriately performing not only the suction during the initial filling but also the air exhaust during the printing operation after the initial filling.

In here, before Symbol than the frequency of performing the first mode, it is desirable that people frequently performing the operation of the second mode is larger. This is because in the second mode, the amount of liquid consumption is small, so that effective bubble discharge can be performed.

Also, after the operation before Symbol first mode, it is desirable to carry out the operation of the second mode. By performing the operation in both modes, the exhaustability at the time of initial filling can be improved.

In the operation in the first mode, it is preferable that the first channel opening / closing means keeps the channel open. For example, if any of the air opening, decompression, and pressurization can be performed in the recess filled with fluid in the flow path opening / closing means, if the pressure is reduced when suctioning the discharge part, the suction from the discharge part is performed. Thus, it is possible to prevent the elastic member from unintentionally closing the flow path.

Another aspect of the present invention is a liquid discharge head including a discharge unit that discharges a liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element. The negative pressure generating means for maintaining the negative pressure of the discharge section, and in the middle of the flow path between the negative pressure generation means and the discharge section, and changing the volume of the flow path to change the flow A pressure adjusting means for adjusting the pressure in the channel, and a channel opening / closing means for opening and closing the flow channel in the middle of the flow path between the negative pressure generating means and the pressure adjusting means in the flow path. A method for controlling a liquid discharge head comprising: a first step of pressurizing the inside of a flow path by the pressure adjusting means in the flow path; and when the inside of the flow path is pressurized by the pressure adjusting means in the flow path, After opening the flow path by the flow path opening / closing means, the pressure adjustment means in the flow path The control method of the liquid discharge head is characterized in that a second step of reducing the pressure in the road.
According to this aspect, the meniscus of the nozzle opening can be formed easily and appropriately when the liquid discharge head is restored to the normal operation after the negative pressure is released.

1 is a schematic perspective view showing a recording apparatus according to an embodiment of the present invention. 1 is a schematic cross-sectional view showing a liquid discharge head according to an embodiment of the present invention. It is a schematic block diagram which extracts and shows a self-sealing unit. It is a disassembled perspective view which shows the flow-path member which concerns on embodiment of this invention. It is a disassembled perspective view which shows the head main body which concerns on embodiment of this invention. It is the upper side figure and back view of a flow-path board | substrate. It is the upper side figure and back view of a flow-path board | substrate. It is the upper side figure and back view of a flow-path board | substrate. It is the upper side figure and back view of a flow-path board | substrate. It is the upper side figure and back view of a flow-path board | substrate. It is the top view and back view which show a 1st flexible member. It is the top view and back view which show a 2nd flexible member. It is a schematic block diagram which shows typically the other Example of a flow-path opening / closing means. It is a schematic block diagram which shows typically the liquid discharge head which concerns on other embodiment. It is a characteristic view which shows the characteristic of the flow-path pressure adjustment means shown in FIG. It is a schematic block diagram which shows typically the liquid discharge apparatus which concerns on other embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
A: Liquid Ejecting Apparatus A liquid ejecting apparatus according to this embodiment is an ink jet recording apparatus, and includes an ink jet recording head as a liquid ejecting head. And it is what is called a line-type recording apparatus which performs printing by conveying recording sheets, such as paper which is a to-be-ejected medium, without moving a liquid discharge head.

  Specifically, as shown in FIG. 1 (a schematic perspective view showing a recording apparatus according to the present embodiment), an ink jet recording apparatus 100 (hereinafter also referred to as a recording apparatus 100) is disposed in the apparatus main body 2. Inkjet recording head unit 1 (hereinafter also referred to as “liquid ejection head unit 1”), an ink cartridge 350 that is an ink supply source that stores ink to be supplied to the liquid ejection head unit 1, an ink cartridge 350, and a liquid ejection head Supports an opening / closing valve 351 that is a channel opening / closing means, a conveying means that conveys a recording sheet S that is a recording medium such as paper, and a reverse side opposite to the printing surface of the recording sheet S. A supporting member 9, a pair of rails 11A and 11B fixed to the floor surface of the apparatus main body 2, a cleaning means 14 disposed on the floor surface of the apparatus main body 2, And a control unit 17 for controlling the operation of each unit of the recording apparatus 100 comprises a. These will be described in detail later.

  In the present embodiment, the conveyance direction of the recording sheet S is referred to as a first direction X. A direction perpendicular to the first direction X in the in-plane direction in which the nozzle openings of the liquid ejection head 3 are opened is referred to as a second direction Y. Furthermore, a direction orthogonal to the first direction X and the second direction Y is referred to as a third direction Z. In the third direction Z, the liquid discharge head 3 side with respect to the recording sheet S is the Z1 side, and the opposite side is the Z2 side.

(A-1-1) Liquid Discharge Head Unit A liquid discharge head unit 1 according to this embodiment is a liquid in which a plurality of ink jet recording heads 3 (hereinafter also referred to as liquid discharge heads 3) are arranged on a base plate 10 in parallel. This is an assembly of the ejection heads 3.

(A-1-2) Liquid discharge head The liquid discharge head 3 according to the present embodiment corresponds to the four colors CMYK and the self-sealing units 4 and 4 to which two colors of ink are supplied, respectively. The flow path member 5 in which four types of flow paths are formed is combined with the head main body 6 to form one unit, and in the present embodiment, this is four in the second direction Y on the base plate 10. It is installed side by side. That is, the liquid ejection head 3 is sandwiched between the two self-sealing units 4 and 4 that are negative pressure generating means and the self-sealing units 4 and 4 from both sides, and is supplied from the self-sealing units 4 and 4. A flow path member 5 that supplies ink to the head main body 6 and a head main body 6 that discharges ink supplied via the flow path member 5 to the print surface of the recording sheet S as ink droplets are provided.

  In this embodiment, the liquid discharge head 3 is disposed on the base plate 10 so as to be inclined with respect to the first direction X. Therefore, the arrangement direction of the liquid ejection head 3 inclined with respect to the first direction X is the fourth direction Xa, and the direction orthogonal to this and inclined with the same amount with respect to the second direction Y is the fifth direction Xa. The direction Ya is referred to. Both are directions on the XY plane.

(A-1-2-1) Head body The head body 6, which will be described in detail later, forms a liquid flow path including a plurality of pressure generation chambers communicating with the nozzles, and causes pressure fluctuations in the ink in the pressure generation chamber. A discharge unit 6A (see FIG. 5; the same applies hereinafter) provided with a pressure generating means composed of a piezoelectric element or the like to be generated, and a filter means 6B (see FIG. 5; the same applies hereinafter) that removes foreign matters of ink supplied to the discharge unit 6A. And have. The head body 6 is disposed on the base plate 10 so as to protrude downward from the lower surface of the base plate 10.

(A-1-2-2) Self-sealing unit The self-sealing unit 4 is described in detail later, and the opening of the concave portion provided on the side surface intersecting the nozzle forming surface of the head body 6 is sealed with a film. It has a liquid channel. Then, a valve body is disposed in the middle of the liquid flow path, and normally, the valve body is energized so as to close the liquid flow path, and the negative pressure in the pressure generating chamber is greater than or equal to a predetermined value as the ink is discharged. In this case, the valve body pressed by the film displaced by the negative pressure opens the liquid flow path. Thus, if a negative pressure of a predetermined value or more is generated in the ejection part 6A of the head body 6 as the ink is ejected, the film presses the valve body, and the valve body is released by this pressing force, so that the ink flows into the liquid channel. The ink flows into the head body 6 and flows.

(A-1-2-3) Distribution unit The distribution unit 18 is placed on the upper surface of the liquid discharge head 3 of each unit and extends in the second direction Y, and the liquid discharge head 3 of each unit is self-sealed. Ink for each color from the ink cartridge 350 is distributed to the unit 4, and the pressure adjusting means (not shown in FIG. 1) and the channel opening / closing means (not shown in FIG. 1) of the channel member 5. The air for drive control is distributed to the flow path members 5 respectively. Here, the dimension (height) in the third direction of the self-sealing unit 4 and the dimension (height) in the third direction of the flow path member 5 are configured to be the same. As a result, the distribution unit 18 that functions as a distribution flow path for ink and air can be easily installed on the liquid ejection head 3 of each unit. More specifically, the self-sealing unit 4 and the flow path member 5 are connected to a common distribution unit 18, and this connection applies a protrusion (convex needle) provided on the lower surface of the distribution unit 18 to a negative pressure. This is performed by inserting the self-sealing unit 4 and the flow path member 5 that are generating means into respective holes (concave insertion holes) provided on the upper surfaces thereof. The distribution unit 18 is provided with a groove along the second direction Y on a planar substrate, and the groove is sealed with a film, whereby a flow path having a distribution function to the liquid ejection head 3 of each unit. It is said. Therefore, the top surfaces of the self-sealing unit 4 and the flow path member 5 are aligned in the height direction, which is the third direction Z, in order to match with the grooves provided along the plane of the distribution unit 18. It should be noted that when the protrusions of the distribution unit 18 are inserted into the self-sealing unit 4 and the holes on the upper surface of the flow path member 5, The length is divided into long and short.

(A-1-2-4) Channel member The channel member 5 will be described in detail later, but the stacked channel substrates 101, 102, 103, 104, 105, the first flexible member 160, and the second It is formed by the flexible member 164 and functions as the flow path pressure adjusting means 161 and the flow path opening / closing means 165.

  The in-channel pressure adjusting means 161 is in the middle of the liquid channel between the self-sealing unit 4 and the head body 6, and adjusts the pressure in the liquid channel by changing the volume of the liquid channel.

  The flow path opening / closing means 165 is in the middle of the liquid flow path between the self-sealing unit 4 and the flow path pressure adjusting means 161, and opens and closes the liquid flow path.

(A-2) Conveying means The conveying means moves the recording sheet S relative to the liquid ejection head 3 in the first direction. The transport unit includes, for example, a first transport roller 7 provided on both sides of the liquid discharge head 3 in the first direction X, which is the transport direction of the recording sheet S, and a second transport roller 8. The recording sheet S is transported upstream and downstream in the first direction X of the liquid discharge head unit 1 by the first transport roller 7 and the second transport roller 8. The conveying means for conveying the recording sheet S is not limited to the conveying rollers 7 and 8, and may be a belt, a drum, or the like.

(A-3) Support Member The support member 9 supports the recording sheet S at a position facing the liquid ejection head unit 1. The support member 9 has, for example, a rectangular cross section provided between the first transport roller 7 and the second transport roller 8 so as to face the nozzle surface of the liquid ejection head 3, particularly the head body 6. The recording sheet S transported by the first transport roller 7 and the second transport roller 8 is supported at a position facing the liquid discharge head unit 1.

  The support member 9 may be provided with a suction unit that sucks the conveyed recording sheet S on the support member 9. Examples of the suction means include a device that sucks and sucks the recording sheet S and a device that electrostatically sucks the recording sheet S by electrostatic force.

  In the recording apparatus 100, the recording sheet S is transported by the first transport roller 7, and printing is performed on the recording sheet S supported on the support member 9 by each liquid ejection head 3. The printed recording sheet S is conveyed by the second conveyance roller 8.

(A-4) A pair of rails The pair of rails 11A, 11B are extended in the second direction Y, and the floor of the apparatus main body 2 via the support members 12A, 12B, 12C and the support members 13A, 13B, 13C. It is fixed to the surface. The rails 11A and 11B are rod-shaped members having a C-shaped receiving section. Both ends of the base plate 10 in the first direction X are inserted into the receiving portion. Thus, the base plate 10 is supported between the rails 11A and 11B and can move along the second direction Y. As a result, the liquid discharge head unit 1 is movable in the second direction along the rails 11A and 11B while being disposed on the base plate 10. That is, in the 2nd direction Y, while moving from the base end part side which is the one end side of rail 11A, 11B to the front end side which is the other side, it also moves to the other side.

(A-5) Cleaning means Cleaning for cleaning a nozzle surface (not shown) of the head main body 6 on the floor surface of the apparatus main body 2 between the rails 11A and 11B in the middle of the rails 11A and 11B. Means 14 are provided. The cleaning means 14 in this embodiment has a wiping means 15 and a suction means 16.

  The wiping means 15 has a wiping blade for wiping the nozzle surface, which is a droplet discharge surface, and the tip of the wiping blade is moved to the nozzle surface by moving the liquid discharge head unit 1 along the second direction Y at a predetermined timing. And a wiping operation for wiping the nozzle surface is performed.

  The suction means 16 is disposed on the floor surface of the apparatus main body 2 adjacent to the wiping means 15 in the second direction Y, and is moved by moving the liquid discharge head unit 1 along the second direction Y at a predetermined timing. A suction operation for forcibly discharging ink or the like from the nozzle opening is performed by covering the nozzle surface with the cap member and sucking the inside of the cap member by applying a negative pressure. Here, the head main body 6 that performs wiping and suction is sequentially positioned above the wiping means 15 and the suction means 16 in the third direction Z as the base plate 10 moves along the Y direction, and performs a predetermined operation. Executed.

(A-6) Control Device The control device 17 controls the operation of each part of the recording apparatus 100. The base plate 10 is moved to a predetermined position together with the ink droplet ejection control and the recording sheet S transport control in the liquid ejection head 3. The cleaning operation is controlled at a predetermined timing accompanied by the movement of. In addition, opening / closing control of the opening / closing valve 351 and driving control of the in-channel pressure adjusting unit 161 and the channel opening / closing unit 165 via air are also performed.

B: Liquid Discharge Head FIG. 2 is a schematic cross-sectional view schematically showing the liquid discharge head according to the embodiment of the present invention. As shown in the figure, the liquid discharge head 3 according to the present embodiment includes two self-sealing units 4 and 4, a flow path member 5, and a head body 6 which are negative pressure generating means. The self-sealing units 4 and 4 are disposed on both sides of the flow path member 5 in the fifth direction Ya. As will be described later in detail, the self-sealing units 4 and 4 are supplied with four colors of CMYK inks through two ink supply ports 126 and 127, respectively. In FIG. 2, the ink supply port 127 is not shown because it overlaps the ink supply port 126. The ink supply ports 126 and (127) are supplied with ink of any color of CMYK from an ink storage means such as an ink cartridge.

(B-1-1) Structure of pressure adjusting means in flow path The flow path member 5 is formed by laminating five flow path substrates 101, 102, 103, 104, and 105. Here, a first recess 158 is formed on the Z2 side surface (hereinafter referred to as the lower surface) of the flow path substrate 104 in the third direction Z, and the Z1 side surface (hereinafter referred to as the upper surface) of the flow path substrate 105. A second recess 159 is formed opposite to the first recess 158. A first flexible member 160 made of rubber, for example, is interposed between the first recess 158 and the second recess 159. As a result, the first recess 158 and the second recess 159 are two chambers sealed by the first flexible member 160. Thus, the volume of the first recess 158 can be adjusted by the amount of displacement of the first flexible member 160 in the third direction Z. The air flow path 172 that opens to the upper surface of the flow path substrate 101 passes through the flow path substrates 101, 102, 103, 104 and reaches the upper surface of the flow path substrate 105. A horizontal flow path 172A communicating with the second concave portion 159 is formed on the upper surface of the flow path substrate 105, and this leads to the second concave portion 159 from the air supply port 170 provided on the upper surface of the flow path substrate 101. The air flow path 172 is communicated. Therefore, by adjusting the amount of air supplied from an air supply source (not shown) as a first fluid supply source for supplying a fluid for driving the pressure adjusting means 161 in the flow path via the air supply port 170, 1 The displacement amount of the flexible member 160 can be adjusted. As will be described later, the first recess 158 communicates with the ink flow path. That is, the first recess 158, the second recess 159, and the first flexible member 160 change the volume of the ink channel to form the in-channel pressure adjusting means 161 that adjusts the pressure in the ink channel. Here, although not shown in the drawing, a spring that applies a biasing force from the first recess 158 toward the second recess 159 is disposed in the first recess 158.

  Three remaining first concave portions 158 and second concave portions 159 having the same configuration are formed on the lower surface of the flow path substrate 104 and the upper surface of the flow path substrate 105, and the first flexible member 160 is further formed in the first concave portions 158. And the second recess 159. That is, a total of four in-channel pressure adjusting means 161 corresponding to each color of CMYK are arranged in a distributed manner on the Xa-Ya plane formed on the lower surface of the channel substrate 104 and the upper surface of the channel substrate 105. . Air is supplied to each of the second recesses 159 including the remaining three through a horizontal flow path 172A that branches in the horizontal direction at the lower end of the air flow path 172, and the same function is exhibited. The first recess 158 communicates with the ink flow path, the second recess 159 communicates with the air flow path, and the first flexible member 160 seals them. The first recess 158 is also referred to as a first recess (ink chamber) 158, and the second recess 159 as an air chamber is also referred to as a second recess (air chamber) 159.

(B-1-2) Structure of Channel Opening / Closing Means On the other hand, a third recess 162 is formed on the upper surface of the channel substrate 103, and a third surface facing the third recess 162 on the lower surface of the channel substrate 102. Four recesses 163 are formed. A second flexible member 164 made of rubber, for example, is interposed between the third recess 162 and the fourth recess 163. As a result, the third concave portion 162 and the fourth concave portion 163 are two chambers sealed with the second flexible member 164. Thus, the flow path can be closed or opened by the displacement of the second flexible member 164 in the third direction Z. The air flow path 171 opening on the upper surface of the flow path substrate 101 passes through the flow path substrate 101 and reaches the upper surface of the flow path substrate 102. A horizontal flow path 171A is formed on the upper surface of the flow path substrate 102, and the air flow path 171 communicates with the fourth recess 163 via the horizontal flow path 171A. As a result, the air flow path 171 from the air supply port 169 provided on the upper surface of the flow path substrate 101 to the fourth recess 163 communicates. Accordingly, the second flexible member 164 is displaced by supplying air from an air supply source (not shown) as a second fluid supply source for supplying a fluid for driving the channel opening / closing means 165 via the air supply port 169. To open and close the channel. As will be described later, the first recess 158 communicates with the ink flow path. That is, the third recess portion 162, the fourth recess portion 163, and the second flexible member 164 form a channel opening / closing means 165 that opens and closes the ink channel.

  Three remaining recesses 162 and fourth recesses 163 having the same configuration are formed on the upper surface of the flow path substrate 103 and the lower surface of the flow path substrate 102, and the second flexible member 164 further includes the third recesses 162. And the fourth recess 163. That is, a total of four channel opening / closing means 165 corresponding to each color of CMYK are distributed and arranged in the center of the Xa-Ya plane formed by the upper surface of the channel substrate 103 and the lower surface of the channel substrate 102. Yes. Air is supplied to each of the fourth recesses 163, including the remaining three, via horizontal flow paths 171A that are formed between the lower surface of the flow path substrate 101 and the upper surface of the flow path substrate 102 and respectively branch in the horizontal direction. The same function is exhibited. Note that the third recess 162 communicates with the ink flow path, the fourth recess 163 communicates with the air flow path, and the second flexible member 164 seals them. The third recess 162 is also referred to as a third recess (ink chamber) 162, and the fourth recess 163 as an air chamber is also referred to as a fourth recess (air chamber) 163.

  In this embodiment, since the volume change amount for pressure adjustment can be increased as the displacement amount of the first or second flexible member 160, 164 increases, the volume of the first recess 158 is larger than the volume of the third recess 162. It is configured. Thus, the predetermined pressure adjustment by the flow path pressure adjusting means 161 can be easily performed with high accuracy.

(B-1-3) The flow path of the flow path member The ink supplied to the flow path member 5 from the one self-sealing unit 4 which is the negative pressure generating means is ejected from the head body 6 via the flow path member 5. To 6A.

  For this reason, the flow path member 5 is formed with flow paths 151, 152, and 153 as ink flow paths. The flow path 151 introduces ink supplied from one of the two self-sealing valves (not shown in FIG. 2) of the one self-sealing unit 4 into the third recess 162. That is, the channel 151 descends the channel substrate 103 from the lower surface of one self-sealing unit 4 along the third direction Z from Z1 to Z2, and the lower surface of the channel substrate 103 and the channel substrate 104 It extends horizontally from the upper surface along the fifth direction Ya from Ya1 to Ya2, and further rises from Z2 to Z1 along the third direction Z to open to the third recess 162. ing. The flow path 152 communicates the third recess 162 and the first recess 158 via the flow path substrate 103 and the flow path substrate 104. The flow path 153 rises from the first recess 158 toward the flow path substrate 104 along the third direction Z from Z2 to Z1 on the Ya1 side of the flow path 152 in the fifth direction Ya. Is horizontally extended along the fifth direction Ya from Ya2 to Ya1, and further penetrates the flow path substrates 104 and 105 and extends along the third direction Z1. Is lowered toward Z2 and communicated with the flow path of the head body 6. Note that a portion of the flow path 153 that extends horizontally between the lower surface of the flow path substrate 103 and the upper surface of the flow path substrate 104 and extends from Ya2 to Ya1 along the fifth direction Ya In the first direction X, a portion of the path 151 that extends horizontally between the lower surface of the flow path substrate 103 and the upper surface of the flow path substrate 104 along the fifth direction Ya from Ya1 to Ya2. Since they overlap, they are not shown.

(B-1-4) Functions of the pressure adjusting means and the flow opening / closing means in the flow path Thus, the flow path from the self-sealing unit 4 which is the negative pressure generating means to the discharge section 6A via the filter means 6B of the head body 6 151, 152, and 153 are formed, and the flow channel opening / closing means 165 is disposed between the flow channel 151 and the flow channel 152, and the pressure in the flow channel is adjusted between the flow channel 152 and the flow channel 153. The means 161 is arranged. That is, a flow path is formed downstream from the self-sealing unit 4 through the flow path opening / closing means 165 and the flow path pressure adjusting means 161 to reach the head main body 6. While adjusting with the internal pressure adjustment means 161, the flow path opening / closing means 165 opens and closes between the flow path internal pressure adjustment means 161 and the self-sealing unit 4. The flow paths 151, 152, and 153 are dispersed in the Xa-Ya plane of the flow path substrates 103, 104, and 105 so as to correspond to the respective colors as flow paths having the same configuration.

  According to the liquid discharge head 3, the following actions and effects are obtained. In this type of liquid discharge head 3, the back pressure in the head (reservoir or pressure chamber) is maintained at a negative pressure in order to manage the position of the meniscus so that it can support continuous discharge. In addition, bubbles near the nozzle opening may be drawn into the nozzle opening due to the negative pressure. If air bubbles are drawn into the nozzle opening, nozzle clogging may occur.

  Therefore, in order to release the negative pressure, the volume in the flow path is decreased and the pressure in the flow path is increased by the pressure adjusting means 161 in the flow path. At that time, if the entire volume in the flow path is larger than the volume fluctuation by the pressure adjusting means 161 in the flow path, pressurization in the flow path cannot be effectively performed against the volume fluctuation. Furthermore, if there is a compliance portion in the flow path, the compliance portion absorbs the volume fluctuation, and the pressurization due to the volume fluctuation of the pressure adjusting means 161 in the flow path cannot be effectively performed. In particular, when the self-sealing unit 4 is used as the negative pressure generating means, as will be described in detail later, since the films 112 and 113 as the flexible members are used, the flexible members become the compliance portions.

  Therefore, in order to effectively perform the pressurization, the flow path opening / closing means 165 is provided on the downstream side of the self-sealing unit 4 and upstream of the flow path pressure adjusting means 161, and the flow path pressure adjusting means 161 is provided. Prior to pressurization by the flow path, the flow path opening / closing means 165 closes the flow path.

  When releasing the pressurization to make the pressure negative, the flow path opening / closing means 165 is opened and then the volume is increased by the flow path pressure adjusting means 161. If the volume is first increased by the pressure adjusting means 161 in the flow path, bubbles may be drawn when the meniscus position is displaced in the drawing direction. On the other hand, if the flow path opening / closing means 165 is opened first, the ink can be supplied from the flow path opening / closing means 165 or upstream thereof even if the volume is increased by the flow path pressure adjusting means 161. As the meniscus position is pulled in, the possibility of bubbles being pulled in can be reduced.

(B-2) Structure of Self-Sealing Unit FIG. 3 is a schematic configuration diagram showing the self-sealing unit extracted, and FIG. 3A is a schematic configuration diagram viewed from the fifth direction Ya, FIG. ) Is a schematic configuration diagram viewed from the Z1 side with respect to the third direction Z, and FIG. 3C is a schematic configuration diagram viewed from the AA ′ cross section of FIG. As shown in these drawings, the self-sealing unit 4 is a substantially rectangular parallelepiped member, and the films 112 and 113 are attached to both sides of the side surface along the longitudinal direction of the main body 111 by heat welding or the like. is there. That is, the self-sealing unit 4 has two film surfaces that are film surfaces along the fourth direction Xa and that face each other in the fifth direction Ya.

  On the other hand, a concave portion (see FIG. 3C) is formed on one side (the left side in the drawing) of one surface of the main body 111 in the fifth direction Ya with respect to the fourth direction Xa. A similar recess (see FIG. 3C) is also formed on the other side (the right side in the drawing) of the other surface in the fourth direction Xa. Such a recess is a space sealed with the films 112 and 113. As a result, the films 112 and 113 are displaced in the fifth direction Ya due to a change in pressure in the space. That is, the diaphragm chambers 114 and 115 are formed by the films 112 and 113 and the recesses. On the opposite surface side of the diaphragm chambers 114 and 115, valve chambers 118 and 119 that are smaller than the recesses and are sealed with the films 113 and 112 are formed through the communication holes 116 and 117. .

  The other end of the shaft 122 that passes through the communication hole 116 is fixed to the valve body 120. One end of the shaft 122 is fixed to the film 112 via a pressure receiving plate or the like (not shown). That is, the valve body 120 is on the side opposite to the film 112 with respect to the communication hole 116. In this embodiment, the valve body 120 side with respect to the communication hole 116 is the Ya1 side with respect to the fifth direction Ya, and the film 112 side with respect to the communication hole 116 is the Ya2 side with respect to the fifth direction Ya. Further, the valve body 120 is pressed from the Ya1 side toward the Ya2 side by the spring 124. Due to the displacement of the film 112 and the bias of the spring 124, the valve body 120 opens or closes the communication hole 116. The spring 124 is fixed to the main body 111 via a spring receiver (not shown).

  Similarly, the other end of the shaft 123 passing through the communication hole 117 is fixed to the valve body 121. One end of the shaft 123 is fixed to the film 113 via a pressure receiving plate or the like (not shown). That is, the valve body 121 is on the side opposite to the film 113 with respect to the communication hole 117. The valve body 121 is pressed by the spring 125 from the Ya2 side toward the Ya1 side. The valve body 121 opens or closes the communication hole 117 by the displacement of the film 113 and the bias of the spring 125. The spring 125 is fixed to the main body 111 via a spring receiver (not shown). As described above, the valve body 120 and the valve body 121 adjacent in the fourth direction Xa are located on both sides of the fifth direction Ya with respect to the communication holes 116 and 117.

  Thus, when a negative pressure is applied to the diaphragm chambers 114 and 115, portions corresponding to the diaphragm chambers 114 and 115 of the films 112 and 113 are displaced along the fifth direction Ya due to atmospheric pressure or the like. As a result, the valve body 120 moves to the Ya1 side in FIG. 3C, and the valve body 121 moves to the Ya2 side in FIG. 3C to open the communication holes 116 and 117, respectively. Here, the diaphragm chambers 114 and 115 are configured such that the negative pressure inside the head body 6 acts when the head body 6 ejects ink through the nozzles.

  Thus, the self-sealing unit 4 in this embodiment forms the film 112, the concave portion forming the diaphragm chamber 114, the self-sealing valve I formed by the valve body 120, the shaft 122 and the spring 124, and the film 113, the diaphragm chamber 115. And a self-sealing valve II formed by a valve body 121, a shaft 123, and a spring 125. Here, the self-sealing valves I and II are arranged apart from each other in the fourth direction Xa. Thus, the shafts 122 and 123 of the valve bodies 120 and 121 are configured so as not to overlap in the third direction Z, and the size of the self-sealing unit 4 in the third direction Z is reduced.

  On the upper surface on the Z1 side in the third direction Z of the main body 111, an ink supply port 126 for supplying ink to the self-sealing valve I side, and an ink supply port 127 for supplying ink to the self-sealing valve II side, Is formed and communicates with the internal flow path. Thus, the inflow ink F111 flowing into the self-sealing valve I side through the ink supply port 126 is supplied as the outflow ink F112 to the head main body 6 from the lower surface formed on the Z2 side of the main body 111, and through the ink supply port 127. Then, the inflow ink F121 flowing into the self-sealing valve II side is supplied to the head body 6 from the lower surface of the main body 111 as the outflow ink F122. More specifically, the ink supplied from the ink supply port 126 reaches the valve chamber 118. In this state, a negative pressure inside the head body 6 acts and a negative pressure exceeding a predetermined value acts on the diaphragm chamber 114. If the valve body 120 opens the communication hole 116 due to the displacement of the film 112, a communication hole is formed accordingly. Ink flows into the diaphragm chamber 114 through the passage 116, is introduced into the flow path 130 where the outlet portion 128 faces the diaphragm chamber 114, descends the back side of the main body 111, and discharges the lower surface of the main body 111 as the outflow ink F 112. It is supplied to the head body 6 through an outlet (not shown).

  On the other hand, the ink supplied from the ink supply port 127 reaches the valve chamber 119. In such a state, when negative pressure acts on the diaphragm chamber 115 and the valve body 121 opens the communication hole 117 due to the displacement of the film 113, ink flows into the diaphragm chamber 115 through the communication hole 117, and this diaphragm It is introduced into the flow path 131 where the outlet 129 faces the chamber 115, descends on the surface side of the main body 111, and is supplied to the head main body 6 through the discharge port (not shown) on the lower surface of the main body 111 as the outflow ink F122. .

  Further, in this embodiment, chamfered portions 132 and 133 are formed on both end surfaces of the main body 111 in the fourth direction Xa in FIG. 3, and an occupied space when a plurality of the self-sealing units 4 are arranged. Is devised to reduce as much as possible. That is, since the self-sealing unit 4 is arranged so that the film surfaces of the films 112 and 113 are along the fourth direction Xa, the outer shape of the self-sealing unit 4 viewed from the Z1 side with respect to the third direction Z is If the shape is rectangular, the dimension in the first direction X is increased. On the other hand, as shown in FIG. 3B, by providing chamfered portions 132 and 133 in the self-sealing unit 4, the dimension in the first direction X is reduced.

  In addition, both of the flow paths 130 and 131 in the self-sealing valves I and II are disposed between the shafts 122 and 123 of the adjacent self-sealing valves I and II. As a result, the dimensions of the self-sealing unit 4 in the fourth direction Xa are compared with the case in which the flow paths 130 and 131 are disposed on both end surfaces in the fourth direction Xa of the main body 111 with respect to the shafts 122 and 123. Can be reduced. In addition, since both of the flow paths 130 and 131 are disposed between the shafts 122 and 123, the chamfered portions 132 and 133 are formed on the end surface of the main body 111 in the fourth direction Xa. The positions of 130 and 131 are not obstructed, and the space occupied when arranging a plurality of the self-sealing units 4 is devised so as to be reduced as much as possible.

  In addition, the self-sealing valves I and II in this embodiment are formed so that a part of the diaphragm chambers 114 and 115 overlap when seen through from the fifth direction Ya, as clearly shown in FIG. It is. Since the self-sealing valves I and II can be brought close to the central portion of the main body 111 in the fourth direction Xa by partially overlapping in this way, this also reduces the dimension in the fourth direction Xa. At the same time, the chamfered portions 132 and 133 can be easily formed.

  In such a self-sealing unit according to this embodiment, the ink supplied by pressure feeding from the distribution unit 18 is discharged toward the flow path member 5 through the diaphragm chambers 114 and 115 that exhibit the self-sealing valve function. The Thereby, even if the ink supplied from the ink supply source is pressurized, the inside of the head body 6 can be maintained at a negative pressure.

(B-3) Laminated Structure of Channel Member FIG. 4 is an exploded perspective view showing the channel member according to the embodiment of the present invention. In the figure, the same parts as those in FIG.

  The channel member 5 is formed by stacking channel substrates 101 (see FIG. 2), 102 (see FIG. 2), 103, 104, and 105. However, since the flow path substrates 101 and 102 are accommodated in the housing 173, they are not shown. Air supply ports 169 and 170 are provided on the upper surface of the housing 173. The air supply ports 169 and 170 are connected to a distribution unit 18 (not shown) via bushings 178 and washers 179, respectively. Communicated. Although not shown, two self-sealing units 4 and 4 are disposed in contact with the side wall surfaces 173A and 173B of the housing 173. The housing 173 and the laminated flow path substrates 103 to 105 are firmly fastened and integrated by a plurality of fastening screws 174 and nuts 176 screwed to the respective fastening screws 174. This is due to the following reason. The uppermost member in the height direction of the in-channel pressure adjusting means 161 forms an air channel 172 communicating with the channel opening / closing means 165. Pressurized air is sent to the air flow path 172. Therefore, in order to maintain the strength of the air flow path 172 even when the pressurized air flows in the air flow path 172, the air is firmly fixed by the fastening screw 174 and the nut 176.

  On the other hand, the fastening screw 175 for fixing the uppermost member in the height direction of the flow path pressure adjusting means 161 is integrated with only the flow path substrates 103 to 105 together with the nut 177 screwed thereto. This is because the second flexible member 164 provided in the flow path opening / closing means 165 is in a position overlapping with the rubber.

  As described above, in the present embodiment, the flow path substrates 101 to 105 have a laminated structure for the following reason. In the present embodiment, the pressure adjusting means 161 in the flow path easily changes the volume in the flow path. In this embodiment, the shape in the middle of the flow path is a room in which the pressure receiving area of the rubber that is the first flexible member 160 is widened. After changing the shape of the rubber, the posture of the rubber is displaced. In addition, as will be described later, since the rubber between the colors of CMYK is not a separate member but a single rubber, the pressure adjusting means 161 for each color of the color is arranged on the same plane. Therefore, there is less excess space in the Xa-Ya in-plane direction where the rubber is disposed. Therefore, the flow path pressure adjusting means 161 and the flow path opening / closing means 165 are laminated in different layers.

  For each color of CMYK, the stacking positions of the flow path pressure adjusting means 161 and the flow path opening / closing means 165 are the same between the colors, and the first flexible member 160 of the flow path pressure adjusting means 161 The rubber which is the second flexible member 164 of the channel opening / closing means 165 can be arranged on the same plane between colors. For this reason, the position where the reaction force is generated can be on the same plane, and the fixing of the flow path substrates 101 to 105 having a laminated structure can be further strengthened. Here, the second flexible member 164 for each color of CMYK may be a single rubber member. Such a structure is preferable from the viewpoint of sandwiching rubber.

  Further, since the stacking positions of the flow path pressure adjusting means 161 and the flow path opening / closing means 165 are the same, the ink flow path and the air flow path between the flow path pressure adjusting means 161 and the flow path opening / closing means 165 are also stacked by CMYK. The position can be the same. Therefore, the flow path substrates 103 to 105, which are laminated substrates for constituting each flow path, can also be a single member between CMYK.

  In this embodiment, the flow path opening / closing means 165 is laminated on the upstream side of the ink, and the flow path pressure adjusting means 161 is laminated on the downstream side. For this reason, the flow path substrates 103 to 105, which are the laminated substrates constituting the flow path opening / closing means 165 and the flow path pressure adjusting means 161, are arranged on the fourth recess (air chamber) 163 of the flow path opening / closing means 165 from the upstream side. The third recess (ink chamber) 162 of the flow path opening / closing means 165 → the first recess (ink chamber) 158 of the pressure adjustment means 161 in the flow path → the second recess (air chamber) 159 of the pressure adjustment means 161 in the flow path. They are stacked in order. By arranging the flow path substrates 103 and 104 for laminating ink in the sequential order from the top to the third layer and the fourth layer, the number of through holes and grooves for ink flow paths provided in the multilayer substrate is reduced. be able to. Note that the air for the channel opening / closing means 165 and the air for the in-channel pressure adjusting means 161 must be pressure controlled at different timings, as will be described later. It must be 172. Even if the laminated substrates for air are continuous in the second and third layers from the top, if the laminated substrates for the air flow path are sandwiched between them, the number of laminated substrates increases.

  Note that the volume of the latter of the third recess 162 that is the ink chamber of the flow path opening / closing means 165 and the first recess 158 that is the ink chamber of the pressure adjusting means 161 in the flow path is larger than the former volume. The flow path opening / closing means 165 only needs to be able to open and close the flow path, whereas the flow path pressure adjusting means 161 has a larger fluctuation range in order to adjust the pressure in the flow path by changing the flow path volume. This is because we want to have For this reason, the installation area of the flow path pressure adjusting means 161 is larger than the installation area of the flow path opening / closing means 165. Then, in order to reduce the size of the entire housing, the flow path opening / closing means 165 is a self-sealing which is a negative pressure generating means with respect to the layer provided with the flow path from the negative pressure generating means (self-sealing unit 4). On the unit 4 side, the flow path pressure adjusting means 161 is arranged on the opposite side. As a result, the channel opening / closing means 165 is disposed between the self-sealing units 4 in the Xa-Ya in-plane direction of the layer. In each of the in-channel pressure adjusting means 161 and the channel opening / closing means 165 in which the first and third recesses 158 and 162 that are ink chambers are sealed by rubber as the first and second flexible members, In the case of the volume, the volume in a state where the first and second flexible members 160 and 162 are not displaced is assumed.

  In addition, the flow path 153 from the pressure adjusting means 161 in the flow path needs to be brought to the four corners of the head unit in consideration of access to the relay board arranged on the XY plane at the downstream side. When viewed through in the stacking direction, the third recess 162, which is the ink chamber of the flow path opening / closing means 165, and the first recess 158, which is the ink chamber of the flow path pressure adjusting means 161, partially overlap each other. It has become the arrangement.

  In addition, the air supply source of the pressure adjusting means 161 in the flow path is common, but since the air flow path provided with through holes in the flow path substrates 101 to 104 is routed from the air supply port 170 in the stacking direction, the pressure in the flow path The air flow path of the adjusting means 161 branches at the lowest side in the stacking direction. Thereby, compared with the case where it branches on the uppermost side in the stacking direction, for example, the number of through-holes provided in the stacked substrate can be reduced, which contributes particularly to miniaturization in the XY direction.

  The seal member 204 is sandwiched between the flow path substrate 103 and the flow path substrate 102 (not shown in FIG. 4), and the third recess 162 as an ink chamber and the fourth recess 163 as an air chamber (see FIG. 4). Is a member for sealing. The seal member 206 is sandwiched between the flow path substrate 105 and the flow path substrate 104 to seal the second recess 159 that is an air chamber and the first recess 158 that is an ink chamber (not shown in FIG. 4). The first flexible member 160 is formed of a flexible rubber member. The first flexible member 160 in this embodiment is integrally formed with four colors of CYMK.

  The first flexible member 160 is always biased toward the second recess 159 by a spring 203 that is a biasing means. As a result, normally, the volume of the first recess 158 (not shown in FIG. 4), that is, the volume of the flow path pressure adjusting means 161 is maximized.

  The ink supplied from the self-sealing unit 4 (see FIG. 2) flows from the four ink inlets 201 provided in the flow path substrate 103 and communicates with the flow path 151. That is, after descending from Z1 to Z2 along the third direction Z, after passing through the horizontal channel formed in the channel substrate 104, and then ascending from Z2 to Z1 along the third direction Z And reaches the third recess 162 of the flow path substrate 103 through the hole 162A. Furthermore, the first recess 158 (not shown in FIG. 4) formed on the back surface of the channel substrate 104 passes through the channel 152 through the hole 162B of the third recess 162. Thereafter, the liquid is supplied to the head main body 6 (not shown in FIG. 4) communicated via the bushing 207 through the flow path 153 provided in the flow path substrate 104.

(B-4) Head Main Body FIG. 5 is an exploded perspective view showing the head main body 6 according to the embodiment of the present invention. As shown in the figure, the head body 6 is composed of a discharge portion 6A and filter means 6B, and is integrated by fixing the filter means 6B to the discharge portion 6A with screws 211. Further, the filter means 6B includes a filter portion 6B1 and a case portion 6B2. By connecting the flow path member 5 to the four ink inflow portions 208 corresponding to each color CMYK of the case section 6B2 via the bushing 207 shown in FIG. 2), and further connected to an ink cartridge 350 (see FIG. 1), which is an ink supply source, via an on-off valve 351. The filter 209 is formed by knitting fine metal wires into a mesh shape, and traps and removes foreign matter in the ink by circulating the ink. The filter 209 is disposed in the opening 210 formed in the case 300 of the filter unit 6B1. As a result, the ink supplied from the flow path member 5 is supplied to the ejection unit 6A after the foreign matter is removed by the filter 209 for each color of CMYK.

  The ejection unit 6A ejects ink droplets through a nozzle opening (not shown) by driving a drive element such as a piezoelectric actuator. Therefore, for example, if the pressure change can be generated in the pressure generation chamber filled with ink by the pressure generation means, the pressure generation means is not particularly limited, but the piezoelectric actuators stacked in the third direction Z are not limited. It can be suitably applied. This type of piezoelectric actuator includes, for example, a thin film type formed by film formation and lithography, and a thick film type formed by a method such as attaching a green sheet. The piezoelectric actuator can be a longitudinal vibration type in which piezoelectric materials and electrode forming materials are alternately stacked and expanded and contracted in the axial direction. Furthermore, as a pressure generating means, a heat generating element is arranged in the pressure generating chamber, and a liquid droplet is discharged from the nozzle opening by a bubble generated by heat generation of the heat generating element, or static electricity is generated between the diaphragm and the electrode. A so-called electrostatic actuator that discharges ink droplets from the nozzle openings by deforming the diaphragm by electrostatic force can also be used.

(B-5) Characteristics and Shapes of Each Laminated Substrate and Each Elastic Member Surface views viewed from the Z1 side in the plan views of the respective flow path substrates 101 to 105 are shown in FIGS. 6 (a) to 10 (a). The back views seen from the side are shown as FIGS. 6 (b) to 10 (b), respectively. 11A is a top view showing the first flexible member, FIG. 11B is a back view thereof, FIG. 12A is a plan view showing the second flexible member, and FIG. FIG. The description of the liquid discharge head 3 according to the present embodiment will be continued by adding these drawings. In these drawings, the same parts as those in FIGS. 2 and 4 are denoted by the same reference numerals, and redundant description is omitted.

  The elastic member of the self-sealing unit 4 which is the negative pressure generating means in this embodiment is formed by the films 112 and 113, whereas the elastic member of the in-channel pressure adjusting means 161 and the channel opening / closing means 165 is the first elastic member. The first and second flexible members 160 and 164 are made of rubber. The reason is as follows. Comparing rubber and film as a flexible member, rubber needs to be firmly clamped with screws to fix it, whereas film only needs to be heat-sealed. The film is easier in terms of fixing the flexible member. Also, from the viewpoint of cost, the film is generally cheaper. However, in terms of the amount of displacement, although it depends on the shape of the rubber in particular, it is easy to obtain a larger rubber. The responsiveness required for the displacement also depends on the shape of the rubber, but the rubber is generally better. In the self-sealing unit 4 which is a negative pressure generating means, a large amount of displacement is not required, so a film is used in consideration of the sticking work and cost. As will be described later, the film is also preferable in that it absorbs the ink flow caused by the operation of the flow path opening / closing means 165. On the other hand, the pressure adjusting means 161 in the flow path and the flow path opening / closing means 165 are responses that are switching when wiping or the like is finished in order to shorten the time required for wiping or the like, which is the purpose. It is preferable that the property is good. Further, it is generally preferable that the amount of displacement is larger than that of the self-sealing unit 4 which is a negative pressure generating means. Therefore, rubber is used for the first and second flexible members 160 and 164.

  Further, in this embodiment, the negative pressure generating means is placed vertically, while the flow path pressure adjusting means 161 and the flow path opening / closing means 165 are placed horizontally. That is, for the self-sealing unit 4 as the negative pressure generating means, the self-sealing unit 4 is arranged so that the direction of displacement of the film as the flexible member is a direction perpendicular to the third direction Z. The pressure in the channel so that the displacement direction of the first flexible member 160 and the second flexible member 164 which are the flexible members of the channel pressure adjusting means 161 and the channel opening / closing means 165 becomes the third direction Z. An adjusting means 161 and a flow path opening / closing means 165 are arranged. The reason is as follows. In the case of vertical installation, there is a risk that bubbles may accumulate on the upper side due to buoyancy. If it is placed horizontally, the possibility that bubbles will accumulate can be reduced. In addition, although the entrance / exit of the flow path in the flow path opening / closing means 165 is below the laminated flow path substrate 103, there is no problem because it is placed horizontally. In addition, the self-sealing unit 4 that is preferably a flexible member having a large pressure-receiving area is preferably placed vertically without being placed horizontally, thereby achieving downsizing from the viewpoint of installation area and space. Yes. As a comparative example, for example, when the self-sealing unit 4 is placed horizontally, in order to secure the pressure receiving area, it is necessary to change the layers with the pressure adjusting means 161 in the flow path and the flow path opening / closing means 165 and stack them. However, in that case, the dimension in the stacking direction (vertical direction) becomes large. In addition, by sharing the layers from the self-sealing unit 4 to the channel opening / closing means 165 between the colors of CMYK, the dimension in the stacking direction is reduced and the number of parts is also reduced.

  Furthermore, in this embodiment, as shown in FIG. 2, the self-sealing unit 4 is disposed on both sides of the flow path member 5, and the pressure adjusting means 161 in the flow path and the flow path opening / closing means 165 are connected to the flow path member 5. Although arranged in the central portion, the length of the flow path between the self-sealing units 4 and 4 and the flow path opening / closing means 165, the size required for the flow path, and the flow path opening / closing means 165 and the flow path The length of the channel between the internal pressure adjusting means 161 and the size required for routing the channel can be reduced. As a comparative example, for example, both the CMYK self-sealing units 4 and 4 are arranged on one side of the flow path member 5, and the CMYK flow path opening / closing means 165 and the pressure adjusting means 161 in the flow path are arranged on the other side. If it is provided, the flow path length becomes long, which is not preferable from the viewpoint of pressure loss and exhaustability. Further, the flow path that communicates one self-sealing unit 4 and the flow path member 5 and the flow path that communicates the other self-sealing unit 4 and the flow path member 5 are arranged in the first direction X. This is not preferable for reducing the size of the liquid discharge head 3 as a whole.

  In this embodiment, regarding the degree of pressurization by the pressure adjusting means 161 in the flow path and the buffer amount, the degree of pressurization by the pressure adjusting means 161 in the flow path is 1) the number of nozzle openings on the downstream side, 2) the degree of meniscus hemisphere, 3 ) It depends on the compliance function in the reservoir and the pressure chamber in the discharge part 6A. An example (although not necessarily limited) of the change amount of the flow path volume by the flow path pressure adjusting means 161 is larger than the reservoir volume of the discharge unit 6A. If it is this level, even if many nozzles are provided with respect to the reservoir | reserver, pressurization can be performed effectively.

  The displacement amount of the first flexible member 160 is specified by the distance between the wall surface of the first recess 158 that is an ink chamber facing the first flexible member 160 and the first flexible member 160. That is, when the first flexible member 160 is displaced and comes into contact with the wall surface of the corresponding first recess 158, the fluid is pressurized as the target value. This makes it easier to pressurize the first flexible member 160 to an unlimited extent as compared with the case where the first flexible member 160 is endlessly displaced, and can prevent the rubber from being broken by excessive pressurization. .

  In this embodiment, the flow path opening / closing means 165 closes the flow path before the flow path volume is changed by the flow path pressure adjusting means 161, but the flow path opening / closing means 165 has the third recessed portion 162 and the second possible opening. Since the flexible member 164 is used, the flow channel volume and the pressure in the flow channel can be changed also by the flow channel opening / closing means 165. Accordingly, for example, the meniscus pressure resistance and the compliance of the reservoir and the tension of the films 112 and 113 of the self-sealing unit 4 are appropriately set so that the ink does not flow from the nozzle openings. Specifically, the flow path resistance from the flow path opening / closing means 165 to the self-sealing unit 4 that is the negative pressure generating means is made smaller than the flow path resistance from the flow path opening / closing means 165 to the nozzle opening. Thereby, even if the flow path is closed by the flow path opening / closing means 165, it is possible to prevent ink from flowing from the nozzle openings.

  As shown in FIG. 9B, a groove 166 radiated from the supply port 167 is provided on the upper surface of the first recess 158 which is an ink chamber of the flow path pressure adjusting means 161 in this embodiment. ing. This is because the first concave portion 158 which is an ink chamber of the pressure adjusting means 161 in the flow path has a circular cross section, and the ink flowing in from the supply port 167 at the center of the circle is at an arbitrary point on the arc from the center. This is because the gas flows out from the discharge port 168 arranged in the direction. That is, the first flexible member 160 that partitions the first concave portion 158 and the second concave portion 159 by pressurizing the flow path pressure adjusting means 161 to the second concave portion 159 that is an air chamber that is an ink chamber causes the ink chamber to When the first flexible member 160 is bent toward the first concave portion 158, the rubber serving as the first flexible member 160 may block the fluid supply port depending on the amount of bending of the first flexible member 160. In addition, choke suction (when sucking the inside of a sealed space provided by a cap to the nozzle opening surface and forcing ink to be ejected from the nozzle opening, the middle of the flow path is closed and negative pressure is applied. Also in the suction performed in order to save, rubber may block the supply port. Therefore, the supply port 167 on the ink chamber side of the pressure adjusting means 161 in the flow path is provided at the bottom of the groove 166 provided at the center of the circle, and the groove 166 is directed from the center of the circle to an arbitrary point on the arc. Even when the first flexible member 160 is bent, the groove 166 secures an ink path as an ink flow path and does not block the supply port 167 or the path from the supply port 167 to the discharge port 168. I am doing so.

  In consideration of air exhaustability in the first concave portion 158 that is an ink chamber, the direction in which the groove 166 extends is preferably not on a straight line from the supply port 167 to the discharge port 168. If it is not on a straight line, the direction in which ink flows in the first recess 158 changes due to the bending of the first flexible member 160, and the air bubbles staying in the first recess 158 before the flow changes are discharged due to the change in flow. It is because it becomes easy to be done.

  In particular, as shown in FIG. 4, the first flexible member 160 is urged from the first recess (ink chamber) 158 toward the second recess (air chamber) 159 in the flow path pressure adjusting means 161. When there is a spring 203, the first flexible member 160 in the flow path pressure adjusting means 161 is displaced toward the second recess (air chamber) 159 and displaced toward the first recess (ink chamber) 158. Each shape can be maintained. If a state of being displaced toward the first concave portion (ink chamber) 158 occurs during printing, the gap between the supply port 167 and the first flexible member 160 becomes narrow, and the pressure loss increases. Therefore, it is desirable to provide a spring 203 that biases from the first recess (ink chamber) 158 side toward the second recess (air chamber) 159 side so as not to cause such displacement during printing. When rubber is used as the first flexible member 160 in the pressure adjusting means 161 in the flow path, it is preferable to use bi-stable rubber in order to maintain the displaced state, and the second recess (air chamber) 159 is used. In a state where the side is opened to the atmosphere (default state), the posture recessed toward the second concave portion (air chamber) 159 can be maintained by the bias of the spring 203. Further, instead of or in addition to the bias of the spring 203, the second recess (air chamber) 159 side may be sucked. Thereby, the displacement of the 1st flexible member 160 during printing can be suppressed reliably.

  Further, in a state where the second recess (air chamber) 159 side is opened to the atmosphere (default state), the first flexible member 160 is recessed toward the second recess (air chamber) 159 side, and is further urged. It is preferable that the two concave portions (air chambers) 159 are in contact with corresponding side surfaces. Thereby, compared with the case where the 1st flexible member 160 is not contacting anywhere, the displacement of the 1st flexible member 160 during printing can be suppressed reliably.

  On the other hand, a spring for urging the second flexible member 164 in the flow path opening / closing means 165 is not provided. The reason is as follows. The in-channel pressure adjusting means 161 and the channel opening / closing means 165 are stacked and fixed by a common screw. At this time, if there is a spring in both the flow path pressure adjusting means 161 and the flow path opening / closing means 165, the assembly becomes difficult. Further, when rubber is used as the second flexible member 164 of the flow path opening / closing means 165, unlike the first flexible member 160 in the flow path pressure adjusting means 161, it is preferable to use film-like rubber ( (See FIG. 12). As a result, the displaced posture is not maintained, and the state in which the rubber of the second flexible member 164 in the flow path opening / closing means 165 blocks the ink flow in the flow path opening / closing means 165 is changed to the pressure in the flow path. Compared with that in the adjusting means 161, it can be made difficult to occur. Therefore, assembly is facilitated by not providing a spring for urging the second flexible member 164 in the flow path opening / closing means 165.

  In addition, when the flow path opening / closing means 165 and the flow path pressure adjusting means 161 are arranged on the same plane, there is no difficulty in assembling, so the second flexible member 164 in the flow path opening / closing means 165 is attached. A spring for biasing may be provided. Thereby, the displacement of the second flexible member 164 during printing can be suppressed. Further, instead of or together with the biasing of the spring, the fourth recess (air chamber) 163 side may be sucked.

  The first flexible member 160 in the flow path pressure adjusting means 161 needs to reduce the volume in the first recess 158 (ink chamber) when the negative pressure is released. Therefore, as shown in FIG. 11, the displacement amount is larger than that of the second flexible member 164 in the flow path opening / closing means 165. Specifically, the thickness on the arc side is made thinner than the thickness of the center part of the circle, and the thinned part is bent in the displacement direction so that the displacement amount is increased. In addition, since it is desired to switch the rubber posture in two stages, when it is desired to release the negative pressure and when it is not, the so-called bi-stable rubber is used so that the rubber posture can be switched stably.

  Note that the second flexible member 164 of the flow path opening / closing means 165 is not a so-called bi-stable rubber, but may be a film-like rubber as shown in FIG. In order to arrange the so-called bi-stable rubber, a larger installation area is required than the film-like rubber. However, if the second flexible member 164 of the channel opening / closing means 165 is a film-like rubber, The installation area required for the road opening / closing means 165 can be reduced. In this embodiment, as shown in FIG. 2, the flow path substrate 102 is made smaller than the flow path substrate 103 in the fifth direction Ya, and the self-sealing units 4 are arranged on both sides of the flow path opening / closing means 165. I am doing so. That is, the self-sealing unit 4 is arranged in the same stacking position as at least one of the flow path substrates 102 and 103 forming the flow path opening / closing means 165 in the third direction Z. Thereby, the liquid discharge head 3 is reduced in size.

  With regard to the distribution of the air flow path, in this embodiment, the third recess 162 that is an ink chamber in the flow path opening / closing means 165 and the first recess 158 that is an ink chamber in the flow path pressure adjusting means 161 are the types of ink. It is necessary to provide for each (color). If not provided, on the premise that the timing of wiping with respect to the nozzle surface is switched for each type of ink, the inside of the third recess 162, which is the ink chamber in the flow path opening / closing means 165, and the pressure adjustment means 161 in the flow path An ink flow path switching mechanism that switches the type of ink that flows to the first recess 158, which is the ink chamber, is required. On the other hand, the third recess 162 in the flow path opening / closing means 165 and the first recess in the flow path pressure adjusting means 161 have the same air for displacing the first and second flexible members 160 and 164. It is not necessary to provide each ink type (color).

  Therefore, the third recess 162 in the flow channel opening / closing means 165 provided for each type of ink may be communicated by an air flow channel or may be a common air chamber. Similarly, the first recess 158 in the flow path pressure adjusting means 161 provided for each type of ink may be in communication or may be a common air chamber. However, when the common air chamber is used, the volume becomes large, so that the effect of pressurizing air is reduced with respect to the pressure receiving area of the flexible member. On the other hand, when an air chamber is provided for each type of ink, the volume of the air chamber is not too large, so the effect of pressurization does not become small.

  When the negative pressure is released, 1) the flow path is closed by the displacement of the second flexible member 164 in the flow path opening / closing means 165, and then 2) the second pressure in the flow path pressure adjusting means 161 is closed. 1 Since the flow path volume needs to be reduced by the displacement of the flexible member 160, the fourth recess 163 in the flow path opening / closing means 165 and the second recess 159 in the flow path pressure adjusting means 161 are connected to a common air chamber. It cannot be. Moreover, when communicating each other's air chamber, an air flow path switching mechanism is required.

  The operation of the channel opening / closing means 165 is performed by switching between pressurization and decompression of the fourth recess (air chamber) 163 in the channel opening / closing means 165. When the flow path of the third recess (ink chamber) 162 in the flow path opening / closing means 165 is closed, the pressure is applied. When releasing the blockage, open the atmosphere. In order to speed up the response of opening and closing the flow path, the blockage may be released by reducing the pressure in addition to (instead of) opening to the atmosphere.

  In addition, if the nozzle opening surface is capped (sealed) with a cap and the ink in the head is forcibly discharged by suctioning the inside of the sealed space by suction of a suction pump provided on the cap side, if you do not want to choke Reduce pressure. If you want to choke, pressurize. When suction is performed in the choked state, the negative pressure is accumulated in the head body 6 and bubbles stuck in the flow path upstream of the filter portion 6B1 of the filter means 6B provided downstream of the flow path opening / closing means 165 are removed. It can be discharged through a filter.

  Regarding the second flexible member 164 of the flow path opening / closing means 165, when the second flexible member 164 for each ink type is on the same plane, the second flexible member 164 for each ink type is a single unit. It can be a member. That is, it is sufficient that one flexible member has a size necessary for the number of types of ink. The same applies to the first flexible member 160 of the flow path pressure adjusting means 161. Further, an ink flow path supplied to the flow path opening / closing means 165 and the flow path pressure adjusting means 161 is also arranged on the plane on which the flexible member in the flow path opening / closing means 165 and the flow path pressure adjusting means 161 is provided. Has been. Since such an ink flow path and the flow path opening / closing means 165 and the pressure adjusting means 161 in the flow path are formed of the same member and these members are laminated, the ink flow path is formed on a plane on which the flexible member is provided. Divided. An O-ring may be used to seal the divided ink flow path, but the O-ring may be provided as a single member with the rubber in the flow path opening / closing means 165 and the flow path pressure adjusting means 161. .

  In the above embodiment, the case where the self-sealing unit 4 is used as the negative pressure generating means has been described. However, in addition to this, the negative pressure may be generated by using the negative pressure in the cartridge. A water head pressure difference obtained by adjusting the position of the tank in which the main body 6 and the flow path communicate with each other with respect to the head main body 6 may be used. In short, it is sufficient if the liquid flow path of the head body 6 can be configured to be a negative pressure.

(Another embodiment of the channel opening / closing means 165)
FIG. 13 is useful as another example of the recording apparatus 100 and the flow path opening / closing means 165 of the liquid ejection head 3 according to the above embodiment. Such channel opening / closing means will be described with reference to the drawings. In addition, in the figure, the same number is attached | subjected to the same part as FIGS. 1-11, and the overlapping description is abbreviate | omitted.

  FIG. 13 is a schematic configuration diagram schematically showing the flow path opening / closing means. As shown in the figure, the channel opening / closing means 165A according to the present embodiment includes a third recess 162A, a fourth recess 163A, and a second flexible member 164A. Here, the third recess 162A communicates with the head body 6 (see FIG. 2) and stores ink. The fourth recess 163A communicates with a fluid supply source (not shown) for supplying air, which is a fluid for operating the flow path opening / closing means 165A, via the air flow path 171A, and stores air. Opposite the recess 162A. The second flexible member 164A is a disc-shaped flexible member formed of rubber or the like that is interposed between the third recess portion 162A and the fourth recess portion 163A and seals the third recess portion 162A and the fourth recess portion 163A. It is a member. More specifically, the second flexible member 164A forms a fourth recess 163A serving as an air chamber by sealing the space on the center side via the seal portion 164A1. Here, the lower end portion of the air flow path 171A is open at the center of the fourth recess 163A.

  Thus, when pressurized air is supplied to the fourth recess 163A, which is a sealed space, via the air flow path 171A, the central portion of the second flexible member 164A is Z2 from the Z1 side in the third direction Z. It is deformed by being pressed to the side, and comes into contact with the opening of the flow path 152A in a state as shown by a two-dot chain line in FIG. 13C, thereby closing the flow path 152A. As a result, the flow of ink from the flow path 151A to the head main body 6 (see FIG. 2) from the flow path 151A via the third recess 162A is stopped at the normal time when the flow path opening / closing means 165A is open. Choke suction is performed in this state.

  Here, in the present embodiment, an annular space 165A1 is provided around the second flexible member 164A to ensure a predetermined deformation of the second flexible member 164A, but this is not necessarily required. is not.

  Furthermore, in this embodiment, the volume of the fourth recess 163A is smaller than that of the third recess 162A. In this way, by making the volume of the fourth recess 163A relatively small, it is possible to reduce the change in the channel volume accompanying the opening / closing of the channel opening / closing means 165A. In particular, the suction is performed when the flow path 151A, 152A is closed with the flow path opening / closing means 351 (refer to FIG. 1) provided on the supply side (ink cartridge 350 (refer to FIG. 1) side). In order to prevent the second flexible member 164A from closing the flow path due to the negative pressure, the inside of the third recess 162A is decompressed, and the second flexible member 164A is brought into contact with the third recess 162A. There is. That is, there is a case where the suction is performed in a contact state, but even in that case, if the volume of the fourth recess 163A is small, the flow path between the decompression in the third recess 162A and the release thereof. Volume fluctuation can be reduced.

  Further, in the fourth recess 163A in the present embodiment, the protrusion 200 is formed at a position in contact with the second flexible member 164A. This will be described in particular with reference to FIG. FIG. 13A shows the ceiling portion of the fourth recess 163A in the third direction Z as seen from the Z2 side to the Z1 side. As shown in the figure, the convex portion 200 is an annular portion protruding from the Z1 side to the Z2 side in the third direction from the ceiling portion of the fourth concave portion 163A, and a plurality of concentrically arranged (this embodiment) 4 in the example).

  By providing the convex portion 200 in this way, the second flexible member 164A can be brought into contact with the convex portion 200 to regulate the position of the second flexible member 164A. It is possible to make the position of the second flexible member 163A of the fourth recess in the normal state and the position of the fourth recess during decompression the same while preventing sticking to the ceiling portion of the fourth recess 163A.

  In the present embodiment, the concentric convex portion 200 is not limited to this structure. If the position of the surface of the second flexible member 164A can be regulated at the normal time, further limitation is not necessary. For example, a structure in which a large number of independent convex portions are arranged on the ceiling portion of the fourth concave portion 163A may be used.

(Another embodiment of the liquid discharge head)
FIG. 14 is a schematic configuration diagram schematically illustrating a liquid discharge head according to the present embodiment. As shown in the figure, the liquid discharge head unit 1A according to the present embodiment includes a plurality of liquid discharge heads 3A and a plurality of in-flow-path pressure adjusting means 161A communicating with the head main bodies 6, respectively. . As will be described in detail later, each internal pressure adjusting means 161A displaces the first flexible member 160A by pressurized air supplied to the second recess 159 via the air flow path 172A, and accompanying this This is for releasing the negative pressure state by pressurizing the flow paths 152A and 153A by changing the volume of the first recess 158A. The suction means 16 discharges bubbles by applying a negative pressure to the ejection portion 6 </ b> A of each head body 6 to suck ink in the head body 6.

  An air supply source 352 that supplies pressurized air to each in-channel pressure adjusting means 161A via an air channel 172A is configured to supply a predetermined pressure of air. That is, in the present embodiment, one air supply source 352 is shared for each pressure adjusting means 161A in each flow path.

  Therefore, the configuration is simplified in comparison with a configuration in which a pressure source such as an air supply source 352 is provided for each negative pressure release mechanism including a self-sealing unit (see FIGS. 1 and 3; the same applies hereinafter). Can do.

  The supply amount and pressure of the air supplied from the air supply source 352 in this embodiment are the pressure adjustment means 161A in the flow path that has the strictest negative pressure release conditions (detailed later) among the plurality of flow path pressure adjustment means 161A. It is adapted to the negative pressure release conditions. That is, when the pressure in each flow path 153A is adjusted by all the flow path pressure adjusting means 161A, from the discharge section 6A corresponding to all the flow path pressure adjusting means 161A, each flow pressure adjustment means in each flow path In accordance with the change in volume at 161A, the ink is ejected.

  Thus, even if the exclusion volume necessary for releasing the negative pressure differs depending on the negative pressure releasing mechanism such as the self-sealing unit 4 or the corresponding head main body 6, the negative pressure releasing mechanism and the head main body that require a small excluded volume are required. The exclusion volume can be reliably formed to such an extent that the negative pressure can be reliably released to all the negative pressure release mechanisms and the head body 6 while allowing the liquid to be discharged from the head 6. As a result, the negative pressure can be reliably released. That is, when the negative pressure release operation is performed by driving the pressure adjusting means 161A in each flow path under the above-described conditions, there is a possibility that the discharge unit 6A from which ink is discharged may appear. The negative pressure can be surely released by the head main body 6. Here, in this embodiment, the ejected ink is collected in the cap of the suction means 16 so that the floor surface of the apparatus main body 2 is not soiled.

  Also in the liquid ejection head 1A according to the present embodiment, although not shown, the channel opening / closing means 165 (see FIG. 2) communicating with each channel 152A is provided upstream of each channel pressure adjusting unit 161A. It is arranged.

  Next, the configuration of the flow path pressure adjusting means 161A will be described in detail. The flow path pressure adjusting means 161A includes a first recess 158A, a second recess 159A, and a first flexible member 160A. The first recess 158A communicates with the head body 6 and stores ink. The second recess 159A communicates with an air supply source 352 that supplies air, which is a fluid for operating the flow path pressure adjusting means 161A, via the air flow path 172A. Thus, air is stored and opposed to the first recess 158A via the first flexible member 160A. The first flexible member 160A is a disk formed of a flexible member such as rubber that is interposed between the first recess 158A and the second recess 159A and seals the first recess 158A and the second recess 159A. Shaped member. The first flexible member 160A is always biased toward the second recess 159A by a spring 203A that is a biasing means. As a result, normally, the volume of the first recess 158A, that is, the volume of the flow path pressure adjusting means 161A is maximized. On the other hand, the lower end of the air flow path 172A is open at the center of the second recess 159A. Thus, when pressurized air is supplied to the second recess 159A, which is a sealed space, through the air flow path 172A, the first flexible member 160A resists the spring force of the spring 203A in the third direction Z. In this regard, it is deformed when pressed from the Z1 side to the Z2 side. As a result, the volume of the first recess 158A decreases, the ink in the flow path 153A communicating with the head body 6 is pressurized, and the negative pressure in the flow path 153A is released.

  Such negative pressure release conditions differ depending on the pressure adjusting means 161A in each flow path. That is, the excluded volume in the first recess 158A necessary for releasing the negative pressure in the flow path pressure adjusting means 161A, and the amount of pressurization from the air supply source 352 for realizing it are 1) self-sealing unit 4 ( The performance in the initial state such as the negative pressure release mechanism such as FIG. 1 and FIG. 3 or the influence of the compliance in the head main body 6 corresponding thereto, and 2) the amount of bubbles in the liquid ejection head 3A is determined as the main parameter. Is done. Therefore, in this embodiment, the worst condition for releasing the predetermined negative pressure is obtained by the pressure adjusting means 161A in the flow path, and the volume of the first recess 158A and the air pressure are set such that the predetermined negative pressure can be released even under this worst condition. Is determined.

  More specifically, among these, the maximum amount of bubbles can be specified by calculation and actual measurement. Further, the performance of the negative pressure release mechanism such as the self-sealing unit 4 can be specified by standards and actual measurements. Therefore, even under worst conditions specified by calculation, standard, and actual measurement, the first flexible member 160A is deformed until the first flexible member 160A sticks to the inner peripheral surface of the first recess 158A in consideration of the elongation of the first flexible member 160A. The volume of the recess 158A is determined and the air pressure is determined.

  FIG. 15 is a graph showing the characteristics of the flow path pressure adjusting means 161A. FIG. 15A is a graph showing the internal pressure of the liquid ejection head 3A with respect to the excluded volume of ink in the first recess 158A when bubbles are present in the liquid ejection head 3A. Showing the relationship. In the figure, ■ indicates that there is no bubble (actual measurement), and ◇ indicates that the bubble is the maximum amount. Referring to the figure, the inclination of the correlation between the excluded volume and the internal pressure of the liquid discharge head 3A changes depending on the size of the bubbles in the liquid discharge head 3A, and the inclination decreases as the amount of bubbles increases. I understand that. Therefore, use the amount of bubbles specified in ◇. (B) shows the relationship of the internal pressure of the liquid ejection head 3A with respect to the excluded volume of ink in the first recess 158A due to the difference in the initial negative pressure in the self-sealing unit 4. In the figure, the initial value decreases in the order of ■, ◇, ●, and ○. Referring to the figure, it can be seen that the intercept of the correlation between the excluded volume and the internal pressure of the liquid discharge head 3A is determined by the initial value of the internal pressure of the liquid discharge head 3A. Therefore, the characteristic of ○ is used as the worst condition.

  Using this parameter, the maximum value of the volume fluctuation amount of the first recess 158A capable of releasing the negative pressure even under the worst condition is obtained, and the air pressure capable of realizing the volume fluctuation amount is determined as described above. Here, in order to uniformly apply the air pressure in each flow path pressure adjusting means 161A, in this embodiment, each liquid discharge head 3A is applied from one air supply source 352 via the air flow path 172A as described above. It has a supply system that can be pressurized. Here, the volume fluctuation amount of one first flexible member 160A is deformed until it sticks to the inner peripheral surface of the first concave portion 158A in consideration of the rubber expansion as the material.

(Another embodiment of the liquid ejection device)
FIG. 16 is a schematic configuration diagram schematically showing a liquid ejection apparatus according to another embodiment of the present invention. As shown in the figure, a liquid ejection apparatus 100A according to this embodiment includes a liquid ejection head including an ink cartridge 350 as a liquid supply source, a channel opening / closing means 165 as a first channel opening / closing means, and a head body 6. 3B and suction means 16. The other mechanisms are not shown. Here, the opening / closing valve 351 as the second opening / closing means is disposed between the flow path 352 connected to the outlet side of the ink cartridge 350 and the flow path 151 reaching the inlet side of the flow path opening / closing means 165. ing. That is, the open / close valve 351 opens and closes the flow path 352 and the flow path 151 on the upstream side (the ink cartridge 350 side) of the flow path opening / closing means 165.

  The channel opening / closing means 165 is disposed between the channel 151 and the channel 152 extending from the channel opening / closing valve 165 to the head body 6. The channel opening / closing means 165 is an opening / closing valve having the same configuration as that shown in FIG. 2 or FIG. In other words, the second flexible member 164 moves from the Z2 side in the third direction Z to the Z1 side by the pressurized air supplied to the fourth recess 163 via the air channel 171, whereby the channels 151 and 152. By closing the gap and releasing the pressure to reduce the pressure, the flow between the flow paths 151 and 152 is opened, and the flow of ink from the flow path 151 toward the flow path 152 is allowed.

  Thus, in this embodiment, under the control of the control device 17, the first mode in which suction is performed by the suction unit 16 while the flow channel 152 is opened by the flow channel opening / closing means 165 and the flow channel 352 is closed by the open / close valve 351, While the flow path 151 is closed by the path opening / closing means 165, the operation in the second mode of suction by the suction means 16 is performed.

  As described above, according to this embodiment, suction in the first mode and the second mode, that is, choke suction can be appropriately performed at a desired timing. Incidentally, in the first mode, ink on the downstream side of the opening / closing valve 351 is sucked, and in the second mode, ink on the downstream side of the flow path opening / closing means is sucked. Accordingly, in the second mode, desired bubbles can be exhausted with a small amount of ink consumption. At the same time, since the distance of the flow path is short, a larger negative pressure can be applied to the inside of the head body 6, so that good air exhaust can be realized. Further, by performing suction in the first mode and then suction in the second mode at the time of initial filling, it is possible to improve the exhaustability at the time of initial filling. Further, not only the suction during the initial filling but also the air exhaustion during the subsequent printing operation is appropriately performed by the effect of the first mode, so that wasteful disposal of the liquid accompanying the suction operation can be reduced as much as possible.

  Further, in the operation in the first mode, the flow channel opening / closing means 165 can be controlled to keep the flow channel 151 open. In this case, the 4th recessed part 163 filled with the air of the flow-path opening-and-closing means 165 presupposes that any of air release, pressure reduction, and pressurization can be performed, 1) It pressurizes when closing the flow path 151. 2) When opening the flow channel 151, the atmosphere is released or reduced in pressure. 3) When suctioning from the discharge unit 6A, the pressure is reduced. In particular, as an effect in the case of 3), the second flexible member 164 may unintentionally close the flow channel 151 due to suction from the discharge unit 6A. Can be prevented.

  In the above-described embodiment, the liquid ejection device includes the pair of rails 11A and 11B and the cleaning unit 14. However, the present invention is not limited thereto, and the liquid ejection head unit 1 may be provided. The head main body 6 only needs to include a pressure generation chamber and pressure generation means for causing pressure fluctuation in the ink in the pressure generation chamber.

  Further, the flow path opening / closing means 165 adjusts the pressure in the flow path by displacing the second flexible member 164 to close or open the ink flow path of the third recess 162 in order to open and close the flow path. Although the volume fluctuation in the flow path by the means 161 is not absorbed on the upstream side of the flow path opening / closing means 165, it is not limited to this. That is, if the volume fluctuation in the flow path by the pressure adjusting means 161 in the flow path can be prevented from being absorbed upstream from the flow path opening / closing means 165, the liquid flow path cannot be completely closed by the opening / closing by the flow path opening / closing means 165. For example, it is only necessary to switch between a state in which the channel resistance between the in-channel pressure adjusting unit 161 and the negative pressure generating unit is small and a large state by opening / closing by the channel opening / closing unit 165. Thereby, pressure loss during printing can be reduced, and volume fluctuation in the flow path by the flow path pressure adjusting means 161 can be prevented from being absorbed upstream of the flow path opening / closing means 165. That is, the case where the flow path is closed by the flow path opening / closing means 165 includes not only the case where the flow path is completely closed, but also the case where the flow path resistance of the flow path is switched from a small state to a large state. The same applies to the case where the flow path opening / closing means 165 is used to reduce the overall volume in the flow path with respect to the volume fluctuation by the flow path pressure adjusting means 161.

  In the above embodiment, as the ink jet recording apparatus 100, a so-called line recording apparatus in which the liquid discharge head unit 1 is fixed to the apparatus main body 2 and printing is performed simply by transporting the recording sheet S is exemplified. However, the present invention is not particularly limited thereto, and the liquid discharge head 3 is mounted on a carriage that moves in the direction crossing the first direction X, which is the conveyance direction of the recording sheet S, for example, in the second direction Y, so The present invention can also be applied to a so-called serial type recording apparatus that performs printing while moving the head 3 in a direction crossing the transport direction.

  Further, in the above-described embodiment, the present invention has been described by exemplifying an ink jet recording head that ejects ink droplets. However, the present invention is widely intended for all liquid ejection heads. Examples of the liquid discharge head include a recording head used in an image recording apparatus such as a printer, a color material ejection head used for manufacturing a color filter such as a liquid crystal display, an organic EL display, and an electrode formation such as an FED (field emission display). Electrode material ejecting heads used in manufacturing, bioorganic matter ejecting heads used in biochip production, and the like.

  DESCRIPTION OF SYMBOLS 1 Liquid discharge head unit, 2 Apparatus main body, 3 Liquid discharge head, 4 Self-sealing unit, 5 Flow path member, 6 Head main body, 18 Distribution unit, 100 Recording apparatus, 101, 102, 103, 104, 105 Flow path board , 112, 113 film, 120, 121 valve body, 130, 131 flow path, 151, 152, 153 flow path, 158 first recess, 159 second recess, 160 first flexible member, 161 pressure control means in flow path 162 third recess, 163 fourth recess, 164 second flexible member, 165 channel opening / closing means, 171, 172 air channel

Claims (13)

A liquid discharge head including a discharge unit that discharges liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element,
A negative pressure generating means communicating with the discharge section and maintaining a negative pressure of the discharge section;
In-channel pressure adjusting means for adjusting the pressure in the flow path by changing the volume of the flow path in the middle of the flow path between the negative pressure generating means and the discharge unit;
A flow path opening / closing means that is in the middle of the flow path between the negative pressure generating means and the pressure adjusting means in the flow path, and that opens and closes the flow path,
When pressurizing the inside of the flow path by the pressure adjusting means in the flow path, the flow path is closed by the flow path opening / closing means prior to pressurization,
When the inside of the channel is pressurized by the in-channel pressure adjusting unit, the inside of the channel is decompressed by the in-channel pressure adjusting unit after the channel is opened by the channel opening / closing unit. Liquid discharge head. The liquid discharge head according to claim 1,
The liquid discharge head according to claim 1, wherein a volume of the pressure adjusting means in the flow path is larger than a volume of the flow path opening / closing means. In the liquid discharge head according to claim 1 or 2,
The volume of the pressure adjusting means in the flow path and the volume of the flow path opening / closing means are adjusted by the displacement amount of the flexible member respectively included in the pressure adjusting means in the flow path and the flow path opening / closing means,
In addition, the displacement amount of the flexible member included in the flow path pressure adjusting means is larger than the displacement amount of the flexible member included in the flow path opening / closing means. In the liquid discharge head according to any one of claims 1 to 3,
The negative pressure generating means has a flexible member that is displaced by the negative pressure,
The liquid discharge head according to claim 1, wherein the flexible member included in the negative pressure generating unit is configured to bend more easily than the flexible member included in the flow path pressure adjusting unit. In the liquid discharge head according to any one of claims 1 to 4,
The channel opening / closing means includes
A third recess that communicates with the discharge section and stores liquid;
A fourth recess that communicates with a fluid supply source that supplies a fluid that operates the flow path opening and closing means, stores the fluid, and faces the third recess;
A second flexible member interposed between the third recess and the fourth recess to seal the third recess and the fourth recess;
With
Furthermore, the volume of the fourth recess is formed smaller than that of the third recess. The liquid ejection head according to claim 5, wherein
The liquid ejection head, wherein the fourth recess has a projection at a position where the fourth recess contacts the second flexible member. In the liquid discharge head according to any one of claims 1 to 6,
The before and Symbol passage pressure regulating means the flow path opening and closing means and the discharge section, there are a plurality of sets,
By supplying the fluid that drives the plurality of sets of pressure adjusting means in the flow path from a common fluid supply source to the plurality of sets of pressure adjusting means in the flow path, all the pressures in the flow paths are set. A liquid discharge head, wherein the pressure in each of the flow paths is adjusted by an adjusting means. A liquid ejection apparatus comprising the liquid ejection head according to any one of claims 1 to 7. The liquid ejection apparatus according to claim 8 , wherein
After wiping the nozzle surface of the discharge portion of the liquid discharge head, the flow path opening / closing means opens the flow path, and the control means for controlling the pressure in the flow path to depressurize the flow path. A liquid ejection apparatus characterized by the above. A liquid discharge apparatus including a discharge unit that discharges liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element,
A first flow path opening / closing means provided in the middle of the flow path between the liquid supply source and the discharge section, for opening and closing the flow path;
A second flow path opening / closing means provided in the middle of the flow path between the liquid supply source and the first flow path opening / closing means;
A suction means for sucking the liquid in the flow path from the discharge section,
A first mode in which suction is performed by the suction means in a state where the flow path is opened by the first flow path opening / closing means and the flow path is closed by the second flow path opening / closing means;
A second mode in which suction is performed by the suction means while the flow path is closed by the first flow path opening and closing means;
Each of the actions
The liquid ejection apparatus, wherein the operation in the second mode is performed after the operation in the first mode. The liquid ejection apparatus according to claim 10 , wherein
The liquid ejection apparatus according to claim 1, wherein the frequency of performing the operation of the second mode is higher than the frequency of performing the first mode. In the liquid ejection device according to claim 10 or 11 ,
In the operation of the first mode, the liquid discharge device is characterized in that the flow path is continuously opened by the first flow path opening / closing means. A liquid discharge head including a discharge unit that discharges a liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element, wherein the discharge unit communicates with the discharge unit, and the discharge unit A negative pressure generating means for maintaining the negative pressure, and a flow for adjusting the pressure in the flow path by changing the volume of the flow path, in the middle of the flow path between the negative pressure generating means and the discharge portion. A method for controlling a liquid ejection head, comprising: a passage pressure adjusting means; and a passage opening / closing means that opens and closes the passage in the middle of the passage between the negative pressure generating means and the passage pressure adjusting means. There,
A first step of pressurizing the inside of the flow path by the pressure adjusting means in the flow path after closing the flow path by the flow path opening and closing means;
When the inside of the flow path is pressurized by the pressure adjusting means in the flow path, the flow path is opened by the flow path opening / closing means, and then the pressure in the flow path is reduced by the pressure adjusting means in the flow path. And a liquid ejection head control method.

Images