JP6969101B2 - Droplet ejection head, droplet ejection device - Google Patents

Description

The present invention relates to a droplet ejection head and a droplet ejection device.

Patent Document 1 describes a technique for increasing the density of electrical wiring in a droplet ejection head in which a plurality of piezoelectric bodies are arranged for one nozzle.

Japanese Unexamined Patent Publication No. 2009-208445

A configuration in which a first pressure chamber and a second pressure chamber are provided for one nozzle, and a supply flow path for supplying ink to the first pressure chamber and the second pressure chamber and a recovery flow path for collecting ink are provided. In the above, when the nozzle density is increased to improve the image quality, the frequency characteristics of the ink ejection are increased while increasing the flow path cross section in order to secure the supply amount of the ink to the first pressure chamber and the second pressure chamber. In order not to make it worse, it was difficult to make the distance between the first pressure chamber and the second pressure chamber and the nozzle an appropriate value.

An object of the present invention is to determine the cross section of the flow path of the supply flow path or the cross section of the flow path of the recovery flow path without being restricted by the positions of the first pressure chamber, the second pressure chamber, and the nozzle. be.

The droplet ejection head according to the first aspect includes a main body member having a nozzle for ejecting droplets, a first pressure chamber and a second pressure chamber connected to the same nozzle, and the first pressure chamber. The first piezoelectric element to be pressed, the second piezoelectric element to pressurize the second pressure chamber, and the second pressure chamber, which are arranged on the opposite side of the nozzle in the main body member, are located in at least one of the first pressure chamber and the second pressure chamber. It is characterized by comprising a flow path member in which a supply flow path for supplying a liquid is formed.

The droplet ejection head according to the second aspect includes a main body member having a nozzle for ejecting droplets, a first pressure chamber and a second pressure chamber connected to the same nozzle, and the first pressure chamber. From at least one of the first pressure chamber and the second pressure chamber, which are arranged on the opposite side of the nozzle in the main body member, the first piezoelectric element to press the pressure, the second piezoelectric element to pressurize the second pressure chamber, and the second pressure chamber. It is characterized by comprising a flow path member in which a recovery flow path for recovering a liquid is formed.

The droplet ejection head according to the third aspect includes a main body member having a nozzle for ejecting droplets, a first pressure chamber and a second pressure chamber connected to the same nozzle, and the first pressure chamber. The first piezoelectric element to be pressed, the second piezoelectric element to pressurize the second pressure chamber, and the second piezoelectric element to pressurize the second pressure chamber are arranged on the opposite side of the nozzle in the main body member to supply a liquid to the first pressure chamber or the second pressure chamber. It is characterized by comprising a flow path member in which a supply flow path to be supplied and a recovery flow path for recovering liquid from the second pressure chamber or the first pressure chamber are formed.

The droplet ejection head according to the fourth aspect is the droplet ejection head according to the third aspect , wherein the main body member has a first passage through which a liquid flowing from the first pressure chamber to the nozzle passes, and the second passage. A second passage through which the liquid flowing from the pressure chamber to the nozzle passes is formed, and the fluid supplied from the supply flow path is recovered by the recovery flow path through the first passage and the second passage. It is characterized by that.

Droplet discharging head according to a fifth aspect, in the droplet ejection head according to any one aspect of the first to fourth embodiments, the nozzle is toward a discharge member that is conveyed in the main scanning direction liquid Droplets are ejected, and the nozzles are arranged in a sub-scanning direction intersecting with the main scanning direction, and the direction in which the first passage extends when viewed from the ejection direction in which the droplets are ejected from the nozzles. And the direction in which the second passage extends intersects with each other.

Droplet discharge apparatus according to a sixth aspect, a liquid droplet ejection head according to any one aspect of the first aspect to fifth aspect, the target discharge member droplets are ejected, it is opposed to the nozzle conveying The transfer member is provided with a control means for controlling the voltage applied to the first piezoelectric element and the second piezoelectric element of the droplet ejection head, and the control means changes the waveform of the applied voltage. It is characterized by deflecting the ejection direction of the droplet.

According to the droplet ejection head of the first aspect , the cross section of the supply flow path can be determined without being restricted by the positions of the first pressure chamber, the second pressure chamber, and the nozzle.

According to the droplet ejection head of the second aspect , the cross section of the recovery flow path can be determined without being restricted by the positions of the first pressure chamber, the second pressure chamber, and the nozzle.

According to the droplet ejection head of the third aspect , the cross section of the flow path of the supply path and the flow path of the recovery flow path are not restricted by the positions of the first pressure chamber, the second pressure chamber, and the nozzle. The cross section can be determined.

According to the droplet ejection head of the fourth aspect , the nozzle is compared with the case where the fluid supplied from the supply flow path is collected in the recovery flow path through only the first pressure chamber and the second pressure chamber. It is possible to suppress an increase in the viscosity of the liquid discharged as droplets from.

According to the droplet ejection head of the fifth aspect , the pitch of the adjacent nozzles is reduced as compared with the case where the first passage and the second passage extend in the sub-scanning direction which is the arrangement direction of the nozzles. Can be done.

According to the droplet ejection apparatus of the sixth aspect, as compared with the case without a liquid droplet ejection head according to any one aspect of the first aspect to fifth aspect, to improve the quality of the output image can.

It is sectional drawing which showed the droplet ejection head which concerns on 1st Embodiment of this invention. It is a top view which showed the droplet ejection head which concerns on 1st Embodiment of this invention. It is a perspective view which showed the droplet ejection head which concerns on 1st Embodiment of this invention. It is an enlarged cross-sectional perspective view which showed the droplet ejection head which concerns on 1st Embodiment of this invention. It is sectional drawing which showed the droplet ejection head which concerns on 1st Embodiment of this invention. (A) (B) (C) It is sectional drawing which showed the droplet ejection head which concerns on 1st Embodiment of this invention. (A) (B) It is a figure which showed the experimental result of the droplet ejection head which concerns on 1st Embodiment of this invention in a graph. It is a figure which showed the experimental result of the droplet ejection head which concerns on 1st Embodiment of this invention in a graph. It is a schematic block diagram which showed the image forming apparatus which concerns on 1st Embodiment of this invention. It is a schematic block diagram which showed the image forming apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which showed the droplet ejection head which concerns on 1st comparative embodiment of this invention. It is sectional drawing which showed the droplet ejection head which concerns on 2nd comparative embodiment of this invention. It is sectional drawing which showed the droplet ejection head which concerns on 3rd comparative embodiment of this invention. It is a top view which showed the droplet ejection head which concerns on 2nd Embodiment of this invention. It is a top view which showed the droplet ejection head which concerns on 3rd Embodiment of this invention. It is a perspective view which showed the droplet ejection head which concerns on 3rd Embodiment of this invention. It is sectional drawing which showed the droplet ejection head which concerns on 3rd Embodiment of this invention. It is sectional drawing which showed the droplet ejection head which concerns on 4th Embodiment of this invention. It is sectional drawing which showed the droplet ejection head which concerns on 5th Embodiment of this invention. It is sectional drawing which showed the droplet ejection head which concerns on 6th Embodiment of this invention.

<First Embodiment>
An example of the droplet ejection head and the image forming apparatus according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 12. The arrow H shown in each figure indicates the vertical direction and the vertical direction of the device, the arrow W indicates the horizontal direction and the width direction of the device, and the arrow D indicates the horizontal direction and the depth direction of the device. ..

(overall structure)
The image forming apparatus 10 is an inkjet recording apparatus, and as shown in FIG. 10, a paper accommodating unit 12 accommodating a sheet member P as a recording medium, an image forming unit 14 forming an image on the sheet member P, and an image forming unit 14. It is provided with a transport unit 16 for transporting the sheet member P. Further, the image forming apparatus 10 includes a control unit 36 that controls each unit and a power supply 56 for supplying electric power to each unit. The image forming apparatus 10 is an example of a droplet ejection device. The details of the power supply 56 will be described later.

[Paper storage]
The paper accommodating unit 12 includes a paper accommodating member 20 on which a plurality of sheet members P are loaded, and a delivery roll 22 that sends the highest-level sheet member P loaded on the paper accommodating member 20 to the transport path 27 of the sheet member P. I have.

[Transport section]
The transport unit 16 includes a plurality of transport rolls (reference numerals omitted) for transporting the sheet member P sent out from the paper accommodating section 12 along the transport path 27. The transport unit 16 is an example of a transport member.

[Image forming part]
The image forming unit 14 is wound around a drive roll 24 that is rotationally driven, a driven roll 26 that is arranged on the right side of the drive roll 24 and is rotatable, and the drive roll 24 and the driven roll 26. It is provided with a transport belt 28. The transport belt 28 is configured to transport the sheet member P while holding the sheet member P by electrostatic adsorption.

Further, the image forming unit 14 ejects ink droplets (an example of droplets) onto the conveyed sheet member P in four colors of yellow (Y), magenta (M), cyan (C), and black (K). It is equipped with four droplet ejection heads 30Y, 30M, 30C, and 30K corresponding to each. The droplet ejection heads 30Y, 30M, 30C, and 30K are arranged between the drive roll 24 and the driven roll 26 in this order from the upstream side in the transport direction of the sheet member P above the transport belt 28. .. When distinguishing between yellow (Y), magenta (M), cyan (C), and black (K), an alphabet is added at the end of the code, and unless otherwise specified, the alphabet at the end of the code is omitted. Further, the image forming unit 14 includes cleaning members 18Y, 18M, 18C, and 18K for cleaning the droplet ejection heads 30 of each color. The droplet ejection head 30 will be described later. Further, in the transport direction of the sheet member P, an image formed on the sheet member P by the ink droplets ejected from the droplet ejection head 30 on the downstream side of the droplet ejection head 30 and above the transport belt 28. A reading sensor 37 for reading is arranged.

In this configuration, when ink droplets are ejected from the droplet ejection head 30 to the sheet member P, as shown in FIG. 10, the droplet ejection head 30 and the cleaning member 18 are separated from each other in the device width direction, and the liquid is liquid. The drop discharge head 30 faces the transport belt 28. On the other hand, when the cleaning member 18 cleans the droplet ejection head 30, as shown in FIG. 9, the droplet ejection head 30 is separated from the transport belt 28, and the cleaning member 18 moves to move the liquid. The drop ejection head 30 and the cleaning member 18 face each other in the vertical direction of the device.

(Action of the whole composition)
Next, the action of forming an image on the sheet member P by using the image forming apparatus 10 will be described.

The uppermost sheet member P loaded on the paper accommodating member 20 is sent out to the transport path 27 by the delivery roll 22. The sheet member P delivered to the transport path 27 is transported along the transport path 27 by a plurality of transport rolls. Further, the seat member P is electrostatically attracted (held) to the transport belt 28.

The sheet member P electrostatically attracted to the conveyor belt 28 is conveyed in the main scanning direction by the orbiting conveyor belt 28. Then, an image is formed on the sheet member P by the ink droplets (droplets) ejected from the droplet ejection head 30 of each color.

The sheet member P on which the image is formed is peeled from the transport belt 28 by a peeling plate (not shown). The peeled sheet member P is transported by a plurality of transport rolls along the transport path 27 and discharged to the outside of the apparatus.

(Main part composition)
Next, the droplet ejection head 30, the power supply 56, and the like will be described.

The droplet ejection head 30 has a rectangular parallelepiped shape extending in the depth direction of the device, and as shown in FIG. 1, the main body member 32 facing the transport belt 28 that conveys the sheet member P and the main body member 32 from above. It has a flow path member 34 that is overlapped with each other.

[Main body member]
The main body member 32 has a rectangular parallelepiped shape extending in the depth direction of the device, and is formed by laminating the nozzle plate 32A, the lower layer portion 32B, the diaphragm 32C, and the upper layer portion 32D in this order. The nozzle plate 32A, the lower layer portion 32B, the upper layer portion 32D, and the diaphragm 32C are made of silicon. Then, as shown in FIGS. 2 and 3, a plurality of ejectors 40 arranged in the device depth direction (sub-scanning direction) are formed on the main body member 32.

The ejector 40 has a nozzle 38 for ejecting ink droplets, as shown in FIGS. 1 and 2. The nozzle 38 is formed on the nozzle plate 32A facing the transport belt 28, and has a rectangular shape when viewed from above. Further, the ejector 40 is located on one side in the device width direction (right side in FIG. 2) with respect to the nozzle 38 and on the back side (upper side in FIG. 2) in the device depth direction with respect to the nozzle 38. It has an arranged deflection portion 70.

− Discharge section −
The discharge unit 50 is a connecting flow path 46 that connects the first pressure chamber 42 filled with ink (an example of a liquid), the first passage 44 connected to the nozzle 38, and the first pressure chamber 42 and the first passage 44. And an auxiliary flow path 48. Further, the ejection unit 50 is for pressurizing the first pressure chamber 42 and applying a voltage to the first piezoelectric element 52 for ejecting ink droplets (an example of droplets) from the nozzle 38 and the first piezoelectric element 52. It has wiring (not shown) (see FIG. 6C).

The first passage 44 is formed in the lower layer portion 32B, and extends in one direction (right side in the drawing) in the device width direction (main scanning direction) with the upper end of the nozzle 38 as a base end. The cross section of the first passage 44 has a rectangular shape extending in the depth direction of the device. The bottom surface forming the first passage 44 is formed by the nozzle plate 32A.

The connecting passage 46 is formed in the lower layer portion 32B, and extends upward with the tip of the first passage 44 as the base end. The cross section of the connecting flow path 46 is circular.

The first pressure chamber 42 is formed in the lower layer portion 32B, and extends in one direction in the width direction of the device with the tip of the connecting flow path 46 as the base end. The cross section of the first pressure chamber 42 has a rectangular shape extending in the depth direction of the device. Further, the first pressure chamber 42 has both ends having an arc shape with respect to a rectangle extending in the device width direction when viewed from above (see FIG. 2). The top surface forming the first pressure chamber 42 is formed by the diaphragm 32C.

The auxiliary flow path 48 is formed in the lower layer portion 32B, the diaphragm 32C, and the upper layer portion 32D, and has a horizontal portion 48A extending in one direction in the device width direction with the tip of the first pressure chamber 42 as the base end. It has a vertical portion 48B extending upward from the tip of the horizontal portion 48A. The cross section of the horizontal portion 48A has a rectangular shape that is thinner than the cross section of the first pressure chamber 42, and the cross section of the vertical portion 48B has a circular shape. Further, the upper end of the vertical portion 48B reaches the upper surface 33 of the main body member 32, and the vertical portion 48B is open to the outside of the main body member 32.

The first piezoelectric element 52 is attached to the opposite side of the first pressure chamber 42 with the diaphragm 32C interposed therebetween. Further, the outer edge of the first piezoelectric element 52 has an arcuate shape at both ends with respect to a rectangle extending in the width direction of the device when viewed from above, and is smaller than the first pressure chamber 42 (see FIG. 2).

In this configuration, the first piezoelectric element 52 to which a voltage (first voltage) is applied pressurizes and depressurizes the first pressure chamber 42 by displaced the diaphragm 32C, and fills the first pressure chamber 42. Pressure is applied to the existing ink. As a result, a pressure wave is transmitted from the first pressure chamber 42 to the nozzle 38 side via the connecting flow path 46 and the first passage 44, and ink droplets are ejected downward from the nozzle 38.

− Deflection part −
The deflection unit 70 includes a second pressure chamber 62 filled with ink, a second passage 64 connected to the nozzle 38, a connecting flow path 66 connecting the second pressure chamber 62 and the second passage 64, and an auxiliary flow path. Has 68 and. Further, the deflection unit 70 pressurizes the second pressure chamber 62 to deflect the ejection direction of the ink droplets ejected from the nozzle 38, and applies a voltage to the second piezoelectric element 72 and the second piezoelectric element 72. It has wiring (not shown) (see FIGS. 6A and 6B).

The second passage 64 is formed in the lower layer portion 32B, and extends from the upper side of the nozzle 38 to the inner side in the device depth direction (sub-scanning direction). The cross section of the second passage 64 has a rectangular shape extending in the width direction of the device. The bottom surface forming the second passage 64 is formed by the nozzle plate 32A.

Then, when viewed from above, the direction in which the second passage 64 extends (see L1 in FIG. 2) and the direction in which the first passage 44 of the discharge portion 50 extends (L2 in FIG. 2) intersect (this). (Orthogonal in the embodiment) (see FIG. 2). In other words, when viewed from the ejection direction in which the ink droplets are ejected from the nozzle 38, the direction in which the first passage 44 extends and the direction in which the second passage 64 extends intersect.

The connecting passage 66 is formed in the lower layer portion 32B, and extends upward with the tip of the second passage 64 as the base end. The cross section of the connecting flow path 66 is circular. The bottom surface forming the connecting flow path 66 is formed of the nozzle plate 32A, and the top surface forming the connecting flow path 66 is formed of the diaphragm 32C.

The second pressure chamber 62 is formed in the lower layer portion 32B, and extends from the tip end of the connecting flow path 66 to the other side (left side in the figure) in the device width direction. The cross section of the second pressure chamber 62 has a rectangular shape extending in the depth direction of the device. Further, the second pressure chamber 62 has an arcuate shape at both ends with respect to a rectangle extending in the device width direction (main scanning direction) when viewed upward (see FIG. 2). Further, the length of the second pressure chamber 62 in the device width direction is shorter than the length of the first pressure chamber 42 in the device depth direction. The volume of the second pressure chamber 62 is smaller than the volume of the first pressure chamber 42.

The auxiliary flow path 68 is formed in the lower layer portion 32B, the diaphragm 32C, and the upper layer portion 32D, and the horizontal portion 68A extending from the tip end of the second pressure chamber 62 to the other end side in the device width direction. And a vertical portion 68B extending upward from the tip of the horizontal portion 68A. The cross section of the horizontal portion 68A has a rectangular shape thinner than the cross section of the second pressure chamber 62, and the cross section of the vertical portion 68B has a circular shape. The upper end of the vertical portion 68B reaches the upper surface 33 of the main body member 32, and the vertical portion 68B is open to the outside of the main body member 32.

The second piezoelectric element 72 is attached to the opposite side of the second pressure chamber 62 with the diaphragm 32C interposed therebetween. Further, the outer edge of the second piezoelectric element 72 has an arcuate shape at both ends with respect to a rectangle extending in the width direction of the device when viewed from above, and is smaller than the second pressure chamber 62 (see FIG. 2).

In this configuration, the second piezoelectric element 72 to which a voltage (second voltage) having the same magnitude as the voltage applied to the first piezoelectric element 52 (first voltage) displaces the vibrating plate 32C. By making the second pressure chamber 62 pressurize and depressurize. Then, the second piezoelectric element 72 applies pressure to the ink filled in the second pressure chamber 62. As a result, the pressure wave is transmitted from the second pressure chamber 62 to the nozzle 38 side through the connecting flow path 66 and the second passage 64, and the ejection direction of the ink droplets ejected from the nozzle 38 is deflected (changed). It has become.

-Other-
Next, the waveform of the voltage applied to the first piezoelectric element 52 (hereinafter referred to as “first voltage”) (hereinafter referred to as “discharge waveform”) and the voltage applied to the second piezoelectric element 72 (hereinafter referred to as “second voltage”). The relationship between the waveform (hereinafter referred to as “biased waveform”) and the ejection direction of the ink droplet ejected by the nozzle 38 will be described.

FIG. 7A is a graph showing the ejection waveform and the deflection waveform, and FIG. 7B shows the deflection angle θ (ejection direction) of the ink droplet ejected from the nozzle 38 and the second voltage. The relationship with is shown.

The vertical axis of the graph shown in FIG. 7A shows voltage, and the horizontal axis shows time. The start point of the deflection waveform is earlier than the start point of the discharge waveform, and the end point of the deflection waveform is delayed by time Td with respect to the start point of the discharge waveform. That is, the time Td is the time from the start point of the discharge waveform to the end point of the deflection waveform. Further, as described above, the second voltage (V1 in the figure) has the same magnitude as the first voltage (V2 in the figure).

The vertical axis of the graph shown in FIG. 7B shows the deflection angle θ of the ink droplets ejected from the nozzle 38, and the horizontal axis shows the second voltage. As for the deflection angle θ, as shown in FIG. 4, the direction of tilting toward the front side in the depth direction of the device is “+” based on the case where the ink droplet is ejected downward from the nozzle 38 (S1 in the figure). The direction of tilting toward the depth of the device is "-". The time Td from the start point of the discharge waveform to the end point of the deflection waveform and the first voltage are not changed.

Then, as shown in the graph of FIG. 7B, when the second voltage is increased, the deflection angle θ increases toward the “−” direction. When no voltage is applied to the second piezoelectric element 72, the deflection angle θ is “0”, and the ink droplets are ejected downward from the nozzle 38.

FIG. 8 is a graph showing the relationship between the deflection angle θ of the ink droplet ejected from the nozzle 38 and the time Td from the start point of the ejection waveform to the end point of the deflection waveform.

The vertical axis of the graph shown in FIG. 8 shows the deflection angle θ of the ink droplets ejected from the nozzle 38, and the horizontal axis shows the time Td (see FIG. 7A). Regarding the time Td, the case where the end point of the deflection waveform and the start point of the discharge waveform are the same as the reference (“0”) is used as a reference (“0”), and the case where the end point of the deflection waveform is delayed with respect to the start point of the discharge waveform is set as “+”. The case where the end point of the deflection waveform is advanced with respect to the start point of the discharge waveform is defined as "-". The discharge waveform and the deflection waveform are not changed.

Then, as shown in FIG. 8, when the time Td is increased to the “+” side, the deflection angle θ is increased to the “−” direction side. On the other hand, when the time Td is increased to the "-" side, the deflection angle θ becomes the "-" direction side, but it is not stable.

As described above, as can be seen from the graphs shown in FIGS. 7 (A) and 7 (B), the deflection angle θ can be changed by changing the second voltage or the time Td.

[Flower path member]
The flow path member 34 is integrally formed of silicon, and as shown in FIG. 1, the flow path member 34 is overlapped with the main body member 32 on the opposite side of the nozzle 38 in the main body member 32. The flow path member 34 is formed with a supply flow path 80 extending in the depth direction of the device and a recovery flow path 84 extending in the depth direction of the device.

The supply flow path 80 is arranged above the discharge portion 50 and extends in the depth direction of the device. The cross section of the supply flow path 80 has a rectangular shape, and the bottom surface of the supply flow path 80 is composed of the upper surface 33 of the main body member 32. The recovery flow path 84 is arranged on the other side in the device width direction with respect to the supply flow path 80 and above the deflection portion 70. The cross section of the recovery flow path 84 has a rectangular shape, and the bottom surface of the recovery flow path 84 is composed of the upper surface 33 of the main body member 32.

〔Power supply〕
The power supply 56 is adapted to supply electric power to each part provided in the image forming apparatus 10 (see FIG. 10). Then, in the present embodiment, the power supply 56 supplies electric power of the same magnitude to the first piezoelectric element 52 (see FIG. 1) and the second piezoelectric element 72 via wiring.

(Action)
Next, the operation of the droplet ejection head 30 and the like will be described.

First, the ink flowing through the ejector 40 will be described.

Ink flowing through the supply flow path 80 is supplied to each ejector 40 from each auxiliary flow path 48 by a driving force of a pump (not shown), and enters the first pressure chamber 42, the connecting flow path 46, and the first passage 44. Flow (see Figure 1). Further, the ink flowing through the first passage 44 passes above the nozzle 38, flows through the second passage 64 of the deflection portion 70, the connecting flow path 66, the second pressure chamber 62, and the auxiliary flow path 68, and is collected. It is collected by the flow path 84.

The start end of the supply flow path 80 and the end end of the recovery flow path 84 are connected to an ink tank (not shown), and the ink includes the supply flow path 80, each ejector 40, and the recovery flow path 84. It circulates in the flow path.

Next, the correction of the output image will be described.

Before starting the print job specified by the user, the control unit 36 (see FIG. 10) conveys the sheet member P, ejects ink droplets from the droplet ejection head 30 of each color to the sheet member P, and causes a test pattern. To create. Then, the reading sensor 37 reads the test pattern formed on the sheet member P. Further, the control unit 36 receives the data read by the reading sensor 37 and confirms the presence or absence of the non-ejection nozzle in which the ink droplet is not ejected.

For example, when the nozzle 38 (hereinafter referred to as “nozzle 38A”) shown in FIG. 5 is a non-ejection nozzle, the control unit 36 may refer to the nozzle 38A on the front side in the depth direction of the device (hereinafter referred to as “nozzle 38B”). A voltage is applied to the second piezoelectric element 72 connected to the). Then, the control unit 36 changes the ejection direction (deflection angle) of the ink droplets ejected from the nozzle 38B, and the point G1 at which the ink droplets ejected by the nozzle 38A land and the ink droplets ejected by the nozzle 38B land. Ink droplets are landed on the point G3 between the position point G2 and the position point G2. By correcting the output image in this way, deterioration of the quality of the output image is suppressed.

(summary)
-Summary 1-
As described above, in the droplet ejection head 30, when viewed from the ejection direction (vertical direction) in which ink droplets are ejected from the nozzle 38, the first passage 44 extends and the second passage 64 extends. It intersects with the direction in which it is (see Fig. 2).

Here, the droplet ejection head 130 according to the first comparative embodiment will be described with reference to FIG. 11. The portion of the droplet ejection head 130 that is different from that of the droplet ejection head 30 will be mainly described.

In the droplet ejection head 130, when viewed from the ejection direction in which ink droplets are ejected from the nozzle 38, the direction in which the first passage 144 of the ejector 140 of the droplet ejection head 130 extends and the second passage 64 extend. As shown in FIG. 11, the first passage 144 and the second passage 64 extend in the device depth direction (secondary scanning direction) without intersecting with the direction in which they are present.

As described above, in the first embodiment, the direction in which the first passage 44 extends and the direction in which the second passage 64 extends intersect with each other when viewed from above. As a result, in the depth direction of the device, the region occupied by the ejector 40 of the droplet ejection head 30 becomes smaller than the region occupied by the ejector 140 of the droplet ejection head 130. Therefore, as can be seen by comparing FIG. 5 and FIG. 11, the pitch of the nozzle 38 of the droplet ejection head 30 (P1 in FIG. 5) is the pitch of the nozzle 38 of the droplet ejection head 130 (FIG. 11). It is smaller than P2).

-Summary 2-
Further, in the droplet ejection head 30, the first pressure chamber 42 and the second pressure chamber 62 extend in the device width direction (main scanning direction) when viewed from above.

Here, the droplet ejection head 132 according to the second comparative embodiment will be described with reference to FIG. The portion of the droplet ejection head 132 that is different from that of the droplet ejection head 30 will be mainly described.

As shown in FIG. 12, the first pressure chamber 142 and the second pressure chamber 162 of the ejector 146 of the droplet ejection head 132 have a square shape when viewed from above. The volume of the first pressure chamber 142 and the volume of the first pressure chamber 42 are the same, and the volume of the second pressure chamber 162 and the volume of the second pressure chamber 62 are the same.

As a result, in the depth direction of the device, the region occupied by the ejector 40 of the droplet ejection head 30 becomes smaller than the region occupied by the ejector 146 of the droplet ejection head 132. Therefore, as can be seen by comparing FIG. 2 and FIG. 12, the pitch of the nozzle 38 of the droplet ejection head 30 (P1 in FIG. 2) is the pitch of the nozzle 38 of the droplet ejection head 132 (P3 in FIG. 12). ), Which is smaller.

-Summary 3-
Further, in the droplet ejection head 30, the first passage 44 extends in the device width direction (main scanning direction), and the second passage 64 extends in the device depth direction (secondary scanning direction). Therefore, when viewed from above, the first passage 44 is tilted in a direction (direction of arrow R1 shown in FIG. 2) in which the angle formed by the first passage 44 and the second passage 64 increases with respect to the main scanning direction. The pitch of the adjacent nozzles 38 becomes smaller than in the case where the nozzles 38 are adjacent to each other.

-Summary 4-
Further, in the droplet ejection head 30, the flow path member 34 in which the supply flow path 80 and the recovery flow path 84 are formed is overlapped with the main body member 32 on the opposite side of the nozzle 38 in the main body member 32.

Here, the droplet ejection head 134 according to the third comparative embodiment will be described with reference to FIG. The droplet ejection head 134 includes a main body 150 in which a plurality of stainless steel etching plates (reference numerals are omitted), a nozzle plate 151 attached to the lower surface of the main body 150, and a first piezoelectric element 152. , A second piezoelectric element 172 is provided.

A nozzle 151A is formed on the nozzle plate 151.

The main body 150 includes a first passage 154 rising from one of the device width directions of the nozzle 151A, a first pressure chamber 156 formed at the upper end of the first passage 154, a first pressure chamber 156, and a nozzle plate 151. A supply flow path 158 arranged between the two is formed. The supply flow path 158 supplies ink to the first pressure chamber 156.

Further, the main body 150 has a second passage 174 rising from the other side in the device width direction of the nozzle 151A, a second pressure chamber 176 formed at the upper end of the second passage 174, a second pressure chamber 176, and a nozzle plate. A recovery flow path 178 arranged between the 151 and 151 is formed. The recovery flow path 178 recovers ink from the second pressure chamber 176. Further, the volume of the second pressure chamber 176 and the volume of the first pressure chamber 156 are the same.

Further, the first piezoelectric element 152 is attached to the opposite side of the first pressure chamber 156 with the ceiling plate 150A forming the top surface of the first pressure chamber 156 and the second pressure chamber 176 interposed therebetween. A second piezoelectric element 172 is attached to the opposite side of the second pressure chamber 176. That is, in the droplet discharge head 134, the supply flow path 158 and the recovery flow path 178 are arranged between the first pressure chamber 156 and the second pressure chamber 176 and the nozzle 151A in the vertical direction of the device. ..

In this configuration, in the droplet ejection head 134, a voltage is applied to the first piezoelectric element 152 and the second piezoelectric element 176 by a power source (not shown). The voltage applied to the second piezoelectric element 176 is smaller than the voltage applied to the first piezoelectric element 152. This is because the volume of the second pressure chamber 176 and the volume of the first pressure chamber 156 are the same, so that a voltage having the same magnitude as the voltage applied to the first piezoelectric element 152 is applied to the second piezoelectric element 172. This is because ink droplets are ejected from the nozzle 151A by driving the second piezoelectric element 172.

Here, as described above, in the droplet ejection head 30, the flow path member 34 in which the supply flow path 80 and the recovery flow path 84 are formed is the main body member 32 on the opposite side of the nozzle 38 in the main body member 32. It is piled up in. On the other hand, in the droplet discharge head 134, the supply flow path 158 and the recovery flow path 178 are arranged between the first pressure chamber 156 and the second pressure chamber 176 and the nozzle 151A in the vertical direction of the device. .. Therefore, as can be seen by comparing FIGS. 1 and 13, the droplet ejection head 30 has the first pressure chamber 56, the second pressure chamber 76, and the nozzle 38, unlike the droplet ejection head 134. The flow path cross sections of the supply flow path 80 and the recovery flow path 84 are determined without being restricted by their respective positions.

-Summary 5-
Further, in the droplet ejection head 30, the first piezoelectric element 52 and the second piezoelectric element 72 are supplied with electric power having the same magnitude from the power supply 56. Therefore, as in the case of the droplet ejection head 134 according to the third comparative embodiment, the voltage applied to the second piezoelectric element 176 is smaller than the voltage applied to the first piezoelectric element 152. The capacity of the second pressure chamber 62 becomes smaller than the capacity of the first pressure chamber 42.

Further, since the capacity of the second pressure chamber 62 is smaller than the capacity of the first pressure chamber 42, the droplet discharge head 30 is downsized as compared with the case where the droplet discharge head 134 is used.

Further, since the first piezoelectric element 52 and the second piezoelectric element 72 are applied with a voltage of the same magnitude, unlike the case where the droplet ejection head 134 is used, one power source uses a resistor or the like. Used without.

-Summary 6-
Further, in the droplet ejection head 30, the ink supplied from the supply flow path 80 to the ejection section 50 flows through the ejection section 50, passes above the nozzle 38, and further flows through the deflection section 70 to collect the ink. Will be recovered by. Therefore, the increase in the viscosity of the ink above the nozzle 38 is suppressed as compared with the case where the ink flows only through the first pressure chamber 42 and the second pressure chamber 62, for example.

-Summary 7-
Further, the ink flowing through the supply flow path 80 flows through the first passage 44, further passes above the nozzle 38, flows through the second passage 64, and is collected by the recovery flow path 84. Therefore, for example, as compared with the case where the ink supplied from the supply flow path 80 flows to the recovery flow path 84 through only the first pressure chamber 42 and the second pressure chamber 62, as ink droplets from the nozzle 38. The increase in the viscosity of the ejected ink is suppressed.

-Summary 8-
Further, in the image forming apparatus 10, by providing the droplet ejection head 30, the pitch of the nozzles 38 becomes smaller than in the case where the droplet ejection head 30 is not provided, so that the quality of the output image is improved.

-Summary 9-
Further, in the image forming apparatus 10, by providing the droplet ejection head 30, the supply flow path 80 is not restricted by the positions of the first pressure chamber 42, the second pressure chamber 62, and the nozzle 38. , And the flow path cross section of the recovery flow path 84 are determined. That is, since the cross sections of the supply flow path 80 and the recovery flow path 84 are determined in consideration of the ejection performance of the ink droplets from the nozzle 38, the quality of the output image is improved in the image forming apparatus 10.

-Summary 10-
Further, in the image forming apparatus 10, by providing the droplet ejection head 30, the capacity of the second pressure chamber 62 is larger than the capacity of the first pressure chamber 42 as compared with the case where the droplet ejection head 30 is not provided. Therefore, the main body of the device is miniaturized.

<Second Embodiment>
Next, an example of the droplet ejection head and the image forming apparatus according to the second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the parts different from the first embodiment will be mainly described.

In the main body member 232 of the droplet ejection head 230 according to the second embodiment, one second pressure chamber 62 and another second pressure chamber 62 arranged next to the first second pressure chamber 62 are provided. A connecting flow path 264 to be connected is formed. That is, in the droplet discharge head 230, two second pressure chambers 62 are connected to each other via the connecting flow path 264.

Other actions are the same as those of the first embodiment.

<Third Embodiment>
Next, an example of the droplet ejection head and the image forming apparatus according to the third embodiment of the present invention will be described with reference to FIGS. 15 to 17. In the third embodiment, the parts different from the first embodiment will be mainly described.

(composition)
As shown in FIGS. 15 and 16, a plurality of ejectors 340 arranged in the depth direction of the device are formed on the main body member 332 of the droplet ejection head 330 according to the third embodiment. Each ejector 340 has a nozzle 38, a discharge unit 350, a first deflection unit 370, and a second deflection unit 380.

The discharge unit 350 pressurizes the first passage 44, the connecting flow path 46, the first pressure chamber 342 extending in one direction in the device width direction from the tip of the connecting flow path 46, and the first pressure chamber 342. It has a piezoelectric element 352 and an auxiliary flow path 48.

The first deflection portion 370 pressurizes the second passage 64, the connecting flow path 66, the second pressure chamber 362 extending from the tip of the connecting flow path 66 to the other in the width direction of the device, and the second pressure chamber 362. It has a second piezoelectric element 372 and an auxiliary flow path 368. The auxiliary flow path 368 will be described later.

The second deflection portion 380 has a third pressure chamber 382, a third passage 384 connected to the nozzle 38, and a connecting flow path 386 connecting the third pressure chamber 382 and the third passage 384. Further, the second deflection unit 380 pressurizes the third pressure chamber 382 and applies a voltage to the third piezoelectric element 392 and the third piezoelectric element 392 that deflect the ejection direction of the ink droplets ejected from the nozzle 38. It has wiring (not shown).

As shown in FIG. 17, the third passage 384 is formed in the lower layer portion 32B, and extends from the upper end of the nozzle 38 to the other side (left side in the figure) in the device width direction. The cross section of the third passage 384 has a rectangular shape extending in the depth direction of the device. The bottom surface forming the third passage 384 is formed by the nozzle plate 32A.

The connecting passage 386 is formed in the lower layer portion 32B, and extends upward with the tip of the third passage 384 as a base end. The cross section of the connecting flow path 386 is circular. The bottom surface forming the connecting flow path 386 is formed of the nozzle plate 32A, and the top surface forming the connecting flow path 386 is formed of the diaphragm 32C.

The third pressure chamber 382 is formed in the lower layer portion 32B, and extends from the tip end of the connecting flow path 386 to the other side in the device width direction. The cross section of the third pressure chamber 382 has a rectangular shape extending in the depth direction of the device. Further, the third pressure chamber 382 is arranged on the front side in the depth direction of the device with respect to the second pressure chamber 362 (see FIG. 15). The top surface forming the third pressure chamber 382 is formed by the diaphragm 32C.

The auxiliary flow path 368 is formed in the lower layer portion 32B, the diaphragm 32C, and the upper layer portion 32D. Then, as shown in FIG. 15, the auxiliary flow path 368 is horizontal to the horizontal portion 368A whose one end is connected to the tip of the second pressure chamber 362 and the other end is connected to the tip of the third pressure chamber 382. It has a vertical portion 368B extending upward from the portion 368A. The upper end of the vertical portion 368B reaches the upper surface 33 (see FIG. 16) of the main body member 32, and the vertical portion 368B is open to the outside of the main body member 32.

Further, the third piezoelectric element 392 is attached to the opposite side of the third pressure chamber 382 with the diaphragm 32C interposed therebetween.

In this configuration, for example, as shown in FIG. 17, when the droplet discharged from the nozzle 38 is deviated from the design target point (G10 in FIG. 17) in one direction in the device width direction (G10 in FIG. 17). G11) in the figure applies a voltage to the third piezoelectric element 392 to deflect the ejection direction of the droplet ejected from the nozzle 38. Specifically, the droplet ejected from the nozzle 38 is set to land at the target point of the design (G10 in FIG. 17).

<Fourth Embodiment>
Next, an example of the droplet ejection head and the image forming apparatus according to the fourth embodiment of the present invention will be described with reference to FIG. In the fourth embodiment, the parts different from the first embodiment will be mainly described.

The droplet ejection head 430 according to the fourth embodiment has a rectangular parallelepiped shape extending in the depth direction of the device, and as shown in FIG. 18, has a main body member 432 facing the transport belt 28 for transporting the sheet member P. It has a flow path member 434 stacked above the main body member 432.

[Main body member]
The main body member 432 has a rectangular parallelepiped shape extending in the depth direction of the device, and is formed by laminating the nozzle plate 432A, the lower layer portion 432B, the diaphragm 432C, and the upper layer portion 432D in this order. The nozzle plate 432A is made of polyimide resin, the lower layer portion 432B and the upper layer portion 432D are made of silicon resin, and the diaphragm 432C is a stainless steel plate. A plurality of ejectors 440 arranged in the device depth direction (sub-scanning direction) are formed on the main body member 432.

The ejector 440 has a nozzle 438 that ejects ink droplets. The nozzle 438 is formed on the nozzle plate 432A and faces the transport belt 28. Further, the ejector 440 is arranged on one side in the device width direction with respect to the nozzle 438 (right side in FIG. 18) and the ejector 450 on the other side in the device width direction with respect to the nozzle 438 (left side in FIG. 18). It has a deflection portion 470 that is provided.

− Discharge section −
The discharge unit 450 has a first pressure chamber 442, a first passage 444 connected to the nozzle 438, a connecting flow path 446 connecting the first pressure chamber 442 and the first passage 444, and an auxiliary flow path 448. ing. Further, the ejection unit 450 includes a first piezoelectric element 452 that pressurizes the first pressure chamber 442 to eject ink droplets from the nozzle 438, and wiring (not shown) for applying a voltage to the first piezoelectric element 452. have.

The first passage 444 is formed in the lower layer portion 432B, and extends in one direction in the width direction of the device with the upper end of the nozzle 438 as a base end. The connecting passage 446 is formed in the lower layer portion 432B, and extends upward with the tip of the first passage 444 as a base end.

The first pressure chamber 442 is formed in the lower layer portion 432B, and extends in one direction in the width direction of the device with the tip of the connecting flow path 446 as a base end. The auxiliary flow path 448 is formed in the lower layer portion 432B, the diaphragm 432C, and the upper layer portion 432D, and extends upward with the tip of the first pressure chamber 442 as the base end. Further, the first piezoelectric element 452 is attached to the opposite side of the first pressure chamber 442 with the diaphragm 432C interposed therebetween.

− Deflection part −
The deflection unit 470 has a second pressure chamber 462, a second passage 464 connected to the nozzle 438, a connecting flow path 466 connecting the second pressure chamber 462 and the second passage 464, and an auxiliary flow path 468. ing. Further, the deflection unit 470 pressurizes the second pressure chamber 462 to apply a voltage to the second piezoelectric element 472 and the second piezoelectric element 472 to deflect the ejection direction of the ink droplets ejected from the nozzle 438. It has wiring (not shown).

The second passage 464 is formed in the lower layer portion 432B, and extends from the upper end of the nozzle 438 to the other side in the device width direction. The connecting passage 466 is formed in the lower layer portion 432B, and extends upward with the tip of the second passage 464 as a base end.

The second pressure chamber 462 is formed in the lower layer portion 432B, and extends from the tip end of the connecting flow path 466 to the other side in the device width direction. The auxiliary flow path 468 is formed in the lower layer portion 432B, the diaphragm 432C, and the upper layer portion 432D, and extends upward with the tip of the second pressure chamber 462 as a base end. Further, the second piezoelectric element 472 is attached to the opposite side of the second pressure chamber 462 with the diaphragm 432C interposed therebetween.

[Flower path member]
The flow path member 434 is integrally formed of silicon resin, and is overlapped with the main body member 432 on the opposite side of the nozzle 438 in the main body member 432. A supply flow path 480 extending in the depth direction of the device is formed in the flow path member 434.

In this configuration, the ink flowing through the supply flow path 480 is supplied from the auxiliary flow path 448 to the ejection section 450, and is supplied from the auxiliary flow path 468 to the deflection section 470.

(summary)
In the droplet ejection head 430, the flow path member 434 in which the supply flow path 480 is formed is overlapped with the main body member 432 on the opposite side of the nozzle 438 in the main body member 432. Therefore, in the droplet discharge head 430, the flow path cross section of the supply flow path 480 is determined without being restricted by the positions of the first pressure chamber 442, the second pressure chamber 462, and the nozzle 438.

<Fifth Embodiment>
Next, an example of the droplet ejection head and the image forming apparatus according to the fifth embodiment of the present invention will be described with reference to FIG. In the fifth embodiment, the parts different from the first embodiment will be mainly described.

The droplet ejection head 530 according to the fifth embodiment has a rectangular parallelepiped shape extending in the depth direction of the device, and as shown in FIG. 19, the main body member 532 facing the transport belt 28 that conveys the sheet member P. It has a flow path member 534 which is overlapped with the main body member 532 from above.

[Main body member]
The main body member 532 has a rectangular parallelepiped shape extending in the depth direction of the device, and is formed by laminating the nozzle plate 532A, the lower layer portion 532B, the diaphragm 532C, and the upper layer portion 532D in this order. The nozzle plate 532A is made of polyimide resin, the lower layer portion 532B and the upper layer portion 532D are made of silicon resin, and the diaphragm 532C is a stainless steel plate. A plurality of ejectors 540 arranged in the device depth direction (sub-scanning direction) are formed on the main body member 532.

The ejector 540 has a nozzle 538 that ejects ink droplets. The nozzle 538 is formed on the nozzle plate 532A and faces the transport belt 28. Further, the ejector 540 is arranged on one side in the device width direction (right side in FIG. 19) with respect to the nozzle 538 and on the other side (left side in FIG. 19) in the device width direction with respect to the nozzle 538. It has a deflection portion 570 which is formed.

− Discharge section −
The discharge unit 550 has a first pressure chamber 542, a first passage 544 connected to the nozzle 538, a connecting flow path 546 connecting the first pressure chamber 542 and the first passage 544, and an auxiliary flow path 548. ing. Further, the ejection unit 550 includes a first piezoelectric element 552 that pressurizes the first pressure chamber 542 to eject ink droplets from the nozzle 538, and wiring (not shown) for applying a voltage to the first piezoelectric element 552. have.

The first passage 544 is formed in the lower layer portion 532B, and extends in one direction in the width direction of the device with the upper end of the nozzle 538 as a base end. The connecting passage 546 is formed in the lower layer portion 532B, and extends upward with the tip of the first passage 544 as the base end.

The first pressure chamber 542 is formed in the lower layer portion 532B, and extends in one direction in the width direction of the device with the tip of the connecting flow path 546 as the base end. The auxiliary flow path 548 is formed in the lower layer portion 532B, the diaphragm 532C, and the upper layer portion 532D, and extends upward with the tip of the first pressure chamber 542 as the base end. Further, the first piezoelectric element 552 is attached to the opposite side of the first pressure chamber 542 with the diaphragm 532C interposed therebetween.

− Deflection part −
The deflection unit 570 has a second pressure chamber 562, a second passage 564 connected to the nozzle 538, a connecting flow path 566 connecting the second pressure chamber 562 and the second passage 564, and an auxiliary flow path 568. ing. Further, the deflection unit 570 pressurizes the second pressure chamber 562 to apply a voltage to the second piezoelectric element 572 and the second piezoelectric element 527 to deflect the ejection direction of the ink droplets ejected from the nozzle 538. It has wiring (not shown).

The second passage 564 is formed in the lower layer portion 532B, and extends from the upper end of the nozzle 538 to the other side in the device width direction. The connecting passage 566 is formed in the lower layer portion 532B, and extends upward with the tip of the second passage 564 as a base end.

The second pressure chamber 562 is formed in the lower layer portion 532B, and extends from the tip end of the connecting flow path 566 to the other side in the device width direction. The auxiliary flow path 568 is formed in the lower layer portion 532B, the diaphragm 532C, and the upper layer portion 532D, and extends upward with the tip of the second pressure chamber 562 as the base end. Further, the second piezoelectric element 572 is attached to the opposite side of the second pressure chamber 562 with the diaphragm 532C interposed therebetween.

-Other-
The recovery flow path 584 is formed in the lower layer portion 532B, is arranged below the first pressure chamber 542, and extends in the depth direction of the device. The recovery passage 584 is connected to the tip of the first passage 544.

[Flower path member]
The flow path member 534 is integrally formed of silicon and is overlapped with the main body member 532 on the opposite side of the nozzle 538 in the main body member 532. The flow path member 534 is formed with a supply flow path 580 extending in the depth direction of the device and connected to the auxiliary flow paths 548 and 568.

In this configuration, the ink flowing through the supply flow path 580 is supplied from the auxiliary flow path 548 to the ejection section 550, and is supplied from the auxiliary flow path 568 to the deflection section 570. The ink supplied to the ejection unit 550 and the deflection unit 570 flows through the first passage 544 and is collected by the collection passage 584.

(summary)
In the droplet ejection head 530, the flow path member 534 in which the supply flow path 580 is formed is overlapped with the main body member 532 on the opposite side of the nozzle 538 in the main body member 532. Therefore, the cross section of the supply flow path 580 is determined without being restricted by the positions of the first pressure chamber 542, the second pressure chamber 562, and the nozzle 538.

<Sixth Embodiment>
Next, an example of the droplet ejection head and the image forming apparatus according to the sixth embodiment of the present invention will be described with reference to FIG. In the sixth embodiment, the parts different from the fifth embodiment will be mainly described.

The supply flow path 680 of the droplet discharge head 630 according to the sixth embodiment is formed in the lower layer portion 532B, is arranged below the first pressure chamber 542, and extends in the depth direction of the device. The supply flow path 680 is connected to the tip of the first pressure chamber 542. Further, the recovery flow path 684 is formed in the flow path member 534, extends in the depth direction of the device, and is connected to the auxiliary flow path 568. The discharge portion 450 of the droplet discharge head 630 does not have an auxiliary flow path connected to the recovery flow path 684.

In this configuration, the ink flowing through the supply flow path 680 is supplied from the first pressure chamber 542 to the ejection unit 550 and then to the deflection unit 570. Then, the ink supplied to the deflection unit 570 flows through the auxiliary flow path 568 and is recovered by the recovery flow path 684.

(summary)
In the droplet ejection head 630, the flow path member 534 in which the recovery flow path 684 is formed is overlapped with the main body member 532 on the opposite side of the nozzle 538 in the main body member 532. Therefore, the cross section of the recovery flow path 684 is determined without being restricted by the positions of the first pressure chamber 542, the second pressure chamber 562, and the nozzle 538.

Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is obvious to the trader. For example, in the first, second, and third embodiments, the supply flow path and the recovery flow path may be exchanged so that the ink flow is in the opposite direction.

Further, although not particularly described in the above embodiment, the droplet ejection head is formed with nozzles arranged in the depth direction of the device, but a plurality of nozzle rows arranged in the depth direction of the device are arranged in a plurality of rows in the width direction of the device. May be.

Further, in the above embodiment, the image forming apparatus has been described as an example of the droplet ejection device, but the droplet ejection device may be a 3D printer or the like.

Further, in the above embodiment, a voltage of the same magnitude is applied to the first piezoelectric element 52, 352, 452, 552 and the second piezoelectric element 72, 372, 472, 572, but the second piezoelectric element. The voltage applied to 72, 372, 472, and 572 may be equal to or higher than the voltage applied to the first piezoelectric elements 52, 352, 452, and 552. However, in this case, the action caused by applying a voltage of the same magnitude to the first piezoelectric element 52, 352, 452, 552 and the second piezoelectric element 72, 372, 472, 527 occurs. No.

Further, in the above embodiment, the number of pressure chambers is two or three for one nozzle, but a plurality of pressure chambers may be used for one nozzle.

10 Image forming device (an example of a droplet ejection device)
16 Transport section (example of transport section)
30 Droplet discharge head 32 Main body member 34 Flow path member 38 Nozzle 42 First pressure chamber 44 First passage 52 First piezoelectric element 62 Second pressure chamber 64 Second passage 72 Second piezoelectric element 80 Supply flow path 84 Recovery flow path 130 Droplet discharge head 132 Droplet discharge head 134 Droplet discharge head 142 First pressure chamber 144 First passage 151A Nozzle 152 First piezoelectric element 154 First passage 156 First pressure chamber 158 Supply flow path 162 Second pressure chamber 172 Second piezoelectric element 174 Second passage 176 Second pressure chamber 176 Second piezoelectric element 178 Recovery flow path 230 Droplet discharge head 232 Main body member 330 Droplet discharge head 332 Main body member 342 First pressure chamber 352 First piezoelectric element 362 No. (2) Pressure chamber 372 Second piezoelectric element 382 Third pressure chamber 384 Third passage 392 Third piezoelectric element 430 Droplet discharge head 432 Main body member 434 Flow path member 438 Nozzle 442 First pressure chamber 444 First passage 452 First piezoelectric element 462 Second pressure chamber 464 Second passage 472 Second piezoelectric element 480 Supply flow path 530 Droplet discharge head 532 Main body member 534 Flow path member 538 Nozzle 542 First pressure chamber 544 First passage 552 First piezoelectric element 562 Second pressure Room 564 Second passage 572 Second piezoelectric element 580 Supply flow path 584 Recovery flow path 630 Droplet discharge head 680 Supply flow path 684 Recovery flow path

Claims (2)

A main body member having a nozzle for ejecting droplets and a first pressure chamber and a second pressure chamber connected to the same nozzle.
The first piezoelectric element that pressurizes the first pressure chamber and
The second piezoelectric element that pressurizes the second pressure chamber and
The main body member is overlapped with the portion of the main body member opposite to the nozzle with respect to the first pressure chamber and the second pressure chamber in the droplet ejection direction of the nozzle, and is the first pressure chamber or the second pressure. A flow path member in which a supply flow path for supplying a liquid to the chamber and a recovery flow path for recovering the liquid from the second pressure chamber or the first pressure chamber are formed.
Equipped with
The main body member is formed with a first passage through which the liquid flowing from the first pressure chamber to the nozzle passes and a second passage through which the liquid flowing from the second pressure chamber to the nozzle passes.
The fluid supplied from the supply flow path is recovered by the recovery flow path through the first passage and the second passage.
The nozzle ejects a droplet toward the ejected member conveyed in the main scanning direction.
The nozzles are aligned in a sub-scanning direction that intersects the main scanning direction.
A droplet ejection head in which the direction in which the first passage extends and the direction in which the second passage extends intersect when viewed from the ejection direction in which the droplet is ejected from the nozzle. The droplet ejection head according to claim 1 and
A transport member that transports the ejected member to which the droplet is ejected so as to face the nozzle, and a transport member.
The first piezoelectric element of the droplet ejection head and the control means for controlling the voltage applied to the second piezoelectric element are provided.
The control means is a droplet ejection device that deflects the droplet ejection direction by changing the waveform of the applied voltage.

Images