Liquid ejecting head and liquid ejecting apparatus

Abstract

The utility model provides a kind of liquid ejection head and liquid ejection device of deformation and paper jam of inhibiting cover are provided.The liquid ejection head has: nozzle plate, with nozzle face (24a), the nozzle face has multiple nozzles (23);And cover (30), with the one opening portion (41) of the part of nozzle face (24a) is exposed, and cover at least part of the outer periphery of nozzle face (24a), cover (30) has the first edge portion (42) of covering the part of outer periphery in nozzle face (24a) in the second direction extending with the first direction orthogonal, first edge portion (42) has the first inner edge (44) of demarcating opening portion (41) inner edge, first inner edge (44) has not with the first part (47,48) of extending substantially parallelly with second direction, the length of the first part (47,48) in second direction is greater than the length of first inner edge (44) in second direction.

Description

Technical Field

[0001] This utility model relates to a liquid ejector head and a liquid ejection device that eject liquid from a nozzle, and particularly to an inkjet recording head and an inkjet recording device that eject ink as a liquid. Background Technology

[0002] Liquid ejection devices, such as inkjet printers and plotters, are equipped with liquid ejection heads capable of ejecting liquids such as ink stored in cartridges or containers. Such liquid ejection heads include: a head body having a nozzle for ejecting liquid, a housing component for holding the head body, and a cover having an opening that allows the nozzle to be exposed (for example, see Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2007-136700

[0004] However, since the inner edge of the opening that exposes the nozzle surface of the cover is straight, when the medium that floats due to poor delivery comes into contact with this straight inner edge, the medium gets stuck in the gap between the nozzle surface and the inner edge, which may cause paper jams or damage to the cover relative to the nozzle plate. Utility Model Content

[0005] The present invention, which solves the above-mentioned technical problems, provides a liquid injection head, characterized in that it comprises: a nozzle plate having a nozzle surface having a plurality of nozzles for injecting liquid along an injection direction; and a cover having an opening that exposes a portion of the nozzle surface when viewed from the opposite direction of the injection direction, and the cover covering at least a portion of the outer periphery of the nozzle surface. When viewed from the injection direction, the nozzle plate is rectangular or substantially rectangular in shape, including a pair of sides extending in a first direction and a pair of sides extending in a second direction orthogonal to the first direction. The cover has a first edge covering the portion of the outer periphery of the nozzle surface extending in the second direction, the first edge having a first inner edge defining the inner edge of the opening, the first inner edge having a first portion extending not substantially parallel to the second direction, the length of the first portion in the second direction being greater than 50% of the length of the first inner edge in the second direction.

[0006] Alternatively, when viewed from the opposite direction of the jet direction, the first inner edge has a straight second portion disposed at the center of the first inner edge in the second direction and extending substantially parallel to the second direction, the first portion having two inclined portions adjacent to the two sides of the second portion and inclined relative to the second direction respectively.

[0007] Alternatively, the first portion may have two curved portions that are respectively disposed at both ends in the second direction of the first inner edge and are curved.

[0008] Alternatively, the first inner edge may have a straight second portion extending substantially parallel to the second direction, the second portion being disposed on the outermost side of the first inner edge in the first direction.

[0009] Alternatively, the tilt angle of the inclined portion relative to the second direction may be 5 to 10 degrees, and the ratio of the length of the inclined portion in the second direction to the length of the first inner edge in the second direction may be 25% to 40%.

[0010] Alternatively, the liquid injection head may move relative to the medium in the first direction while injecting liquid along the injection direction.

[0011] Alternatively, the edge of the nozzle plate extending in the second direction may contact the abutment portion of the first edge of the cover, and when viewed from the second direction, the first edge extends from the abutment portion toward the first inner edge of the cover in a manner away from the nozzle plate.

[0012] In addition, another aspect of this utility model provides a liquid injection head, characterized in that it is a liquid injection head that sprays liquid along an injection direction while moving relative to a medium in a first direction. The liquid injection head includes: a nozzle plate having a nozzle surface having a plurality of nozzles for spraying liquid; and a cover having an opening that exposes a portion of the nozzle surface when viewed from the opposite direction of the injection direction, and the cover covering at least a portion of the outer periphery of the nozzle surface. The cover has a first edge covering a portion of the outer periphery of the nozzle surface extending in a second direction orthogonal to the first direction. The first edge has a first inner edge defining the inner edge of the opening. The proportion of one or more straight segments that are located at the same position in the first direction and define the first inner edge and extend substantially parallel to the second direction is less than 50% relative to the length of the first inner edge in the second direction.

[0013] Alternatively, the first inner edge may have at least one of an inclined portion that is inclined relative to a straight line parallel to the second direction and a curved portion.

[0014] Alternatively, the first inner edge may have a first portion that extends not substantially parallel to the second direction, and the length of the first portion in the second direction is greater than 50% of the length of the first inner edge in the second direction.

[0015] Alternatively, when viewed from the opposite direction of the jetting direction, the nozzle plate may be a rectangle or approximately rectangular shape comprising a pair of sides extending in the first direction and a pair of sides extending in the second direction.

[0016] Alternatively, the first inner edge may have a plurality of straight sections that are staggered in the first direction, define the first inner edge, and extend substantially parallel in the second direction.

[0017] In addition, another embodiment of the present invention provides a liquid injection head, characterized in that it is a liquid injection head that sprays liquid along an injection direction while moving relative to a medium in a first direction. The liquid injection head comprises: a nozzle plate having a nozzle surface having a plurality of nozzles for spraying liquid; and a cover having an opening that exposes a portion of the nozzle surface when viewed from the opposite direction of the injection direction, and the cover covering at least a portion of the outer periphery of the nozzle surface. The cover has a first edge covering a portion of the outer periphery of the nozzle surface extending in a second direction orthogonal to the first direction. The first edge has a first inner edge defining the inner edge of the opening. The first inner edge has an inclined portion or a curved portion that is inclined relative to a straight line parallel to the second direction at least in the central portion of the second direction.

[0018] In addition, other forms of this utility model provide a liquid injection device, characterized in that it comprises: a liquid injection head as described above; a carriage for holding the liquid injection head and reciprocating in the first direction; and a conveying mechanism for conveying a medium in the second direction at a position facing the nozzle.

[0019] In addition, another embodiment of the present invention provides a liquid injection device, characterized in that it comprises: a horizontal head composed of a liquid injection head as described above; and a conveying mechanism for conveying a medium in the first direction at a position facing the nozzle. Attached Figure Description

[0020] Figure 1 This is a diagram showing the schematic configuration of the liquid injection device according to Embodiment 1.

[0021] Figure 2 This is a cross-sectional view of the main parts of the liquid injection device involved in Embodiment 1.

[0022] Figure 3 This is an exploded perspective view of the liquid injection head involved in Embodiment 1.

[0023] Figure 4 This is a cross-sectional view of the liquid injection head according to Embodiment 1.

[0024] Figure 5 This is a top view of the liquid injection head according to Embodiment 1.

[0025] Figure 6 This is a cross-sectional view of the main part of the liquid injection head involved in Embodiment 1.

[0026] Figure 7 This is a top view of the liquid injection head and the medium involved in Embodiment 1.

[0027] Figure 8 This is a partial cross-sectional view showing the contact state between the cover and the medium according to Embodiment 1.

[0028] Figure 9 This is a top view of the liquid injection head and the medium involved in the comparative example.

[0029] Figure 10 This is a partial cross-sectional view showing the contact state between the cover and the medium in the comparative example.

[0030] Figure 11 This is a top view showing a modified example of the liquid injection head according to Embodiment 1.

[0031] Figure 12 This is a top view of the liquid injection head according to Embodiment 2.

[0032] Figure 13 This is a top view of the liquid injection head according to Embodiment 3.

[0033] Figure 14 This is a top view of the liquid injection head according to Embodiment 4.

[0034] Figure 15 This is a top view of the liquid injection head according to Embodiment 5.

[0035] Figure 16 This is a top view of the liquid injection head according to Embodiment 6.

[0036] Figure 17 This is a diagram illustrating the schematic configuration of a liquid injection device according to other embodiments.

[0037] Explanation of reference numerals in the attached figures

[0038] H…Liquid jet head, LH…Rotating head, S…Media, 1…Liquid jetting device, 3…Liquid storage section, 4…Control section, 5…First conveying mechanism, 5a…First conveying roller, 5b…First driven roller, 6…Second conveying mechanism, 6a…Second conveying roller, 6b…Second driven roller, 7…Moving mechanism, 7a…Carriage, 7b…Conveyor belt, 8…Support member, 9…Phase body, 11…Head holder, 12…Mounting section, 13…Ink flow path, 14…Flow path forming section, 15…Flow path connection section, 16…Filter, 17…Sealing member, 18…Circuit board, 19…Head component, 20…Piezoelectric actuation Device unit, 21…head housing, 22…head body, 23…nozzle, 24…nozzle plate, 24a…nozzle surface, 24b, 24c…edge, 25…pressure chamber, 26…flow path forming substrate, 27…vibrating plate, 28…ink supply path, 30…cover, 40…frame portion, 41…opening portion, 42…first edge portion, 42a…abutment portion, 43…second edge portion, 44…first inner edge, 45…second inner edge, 46…straight portion, 46a…first straight portion, 46b…second straight portion, 47…inclined portion, 48…bent portion, 50…side wall portion, 51…flange portion, 52…screw, 100…support body. Detailed Implementation

[0039] The present invention will now be described in detail based on the embodiments. However, the following description represents one form of the present invention, and any modifications can be made within the scope of the present invention. The same reference numerals are used in the figures to denote the same components, and descriptions are omitted where appropriate. Furthermore, in the figures, X, Y, and Z represent three mutually orthogonal spatial axes. In this specification, the directions along these axes are the X direction, Y direction, and Z direction. The direction in which the arrows point in each figure is defined as the positive (+) direction, and the opposite direction is defined as the negative (-) direction. Furthermore, the Z direction represents the vertical direction, +Z direction represents vertically downward, and -Z direction represents vertically upward. Moreover, the directions of the three spatial axes, which are not limited to positive and negative directions, will be described as the X-axis direction, Y-axis direction, and Z-axis direction.

[0040] Implementation Method 1

[0041] Figure 1 This is a diagram showing the schematic configuration of the liquid injection device 1 of this utility model. Figure 2 This is a cross-sectional view of the main part of the liquid injection device 1 of Embodiment 1 viewed in the Y-axis direction.

[0042] The liquid ejection device 1 includes a liquid ejection head H capable of ejecting ink, a liquid, as ink droplets. The liquid ejection device 1 is a so-called serial printer that, while conveying a medium S in the X-axis direction and reciprocating the liquid ejection head H in the Y-axis direction, ejects ink droplets (also called ejections) from the liquid ejection head H toward the medium S in the +Z direction, thereby causing them to land on the medium S, such as printing paper, and prints images, etc., by arranging the dots formed on the medium S. Furthermore, the medium S can be any material besides recording paper, such as resin film or cloth.

[0043] The liquid injection device 1 includes: a liquid injection head H, a liquid storage unit 3, a control unit 4, a first conveying mechanism 5 and a second conveying mechanism 6 for conveying medium S, a moving mechanism 7, and a support component 8.

[0044] The liquid jet head H ejects ink supplied from the liquid storage unit 3 as ink droplets in the +Z direction.

[0045] The support member 8 is positioned in the +Z direction of the liquid jet head H, supporting the back side of the medium S opposite to the printing surface, the surface on which ink droplets fall. Ink droplets from the liquid jet head H fall onto the printing surface of the medium S, which is supported by the support member 8.

[0046] The liquid storage section 3 stores the ink ejected from the liquid ejector head H. Examples of liquid storage sections 3 include detachable cartridges for the liquid ejection device 1, pouch-shaped ink cartridges made of flexible film, and ink refill containers. Although not specifically illustrated, the liquid storage section 3 may store various types of ink with different colors and compositions. Furthermore, the liquid storage section 3 may consist of a main container and a secondary container. Alternatively, the secondary container may be connected to the liquid ejector head H, and the ink consumed by ejecting ink droplets from the liquid ejector head H may be replenished from the main container to the secondary container.

[0047] The control unit 4 may include, for example, a control device such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array), and a storage device such as a semiconductor memory. The control unit 4 executes the program stored in the storage device through the control device to uniformly control the various elements of the liquid injection device 1, namely, the liquid injection head H, the first conveying mechanism 5, the second conveying mechanism 6, and the moving mechanism 7.

[0048] The first conveying mechanism 5 and the second conveying mechanism 6 convey the medium S in the X-axis direction. The first conveying mechanism 5 is located further in the -X direction than the support member 8, and the second conveying mechanism 6 is located further in the +X direction than the support member 8.

[0049] The first conveying mechanism 5 includes a first conveying roller 5a and a first driven roller 5b driven by the first conveying roller 5a. The first conveying roller 5a is disposed on the back side of the medium S, and the first driven roller 5b is disposed on the printing surface side of the medium S. The first conveying mechanism 5 conveys the medium S in the X-axis direction by rotating the first conveying roller 5a using a drive motor (not shown) or the like. That is, the medium S is conveyed from one side in the X-axis direction, i.e., the -X direction side, to the support member 8 by the first conveying mechanism 5, where it is supported by the support member 8 and allows ink droplets ejected from the liquid jet head H to fall. In addition, the first driven roller 5b contacts the printing surface of the medium S before printing, pressing the medium S to float off the first conveying roller 5a. Therefore, the first driven roller 5b is composed of a so-called rubber roller with rubber provided on its surface.

[0050] The second conveying mechanism 6 includes a second conveying roller 6a and a second driven roller 6b driven by the second conveying roller 6a. The second conveying roller 6a is disposed on the back side of the medium S, and the second driven roller 6b is disposed on the printing surface side of the medium S. The second conveying mechanism 6 conveys the medium S in the X-axis direction by rotating the second conveying roller 6a using a drive motor (not shown) or the like. That is, the medium S, to which ink droplets ejected from the liquid jet head H fall, is conveyed from the support member 8 in the +X direction by the second conveying mechanism 6. In addition, the second driven roller 6b contacts the printing surface of the printed medium S, preventing the medium S from floating off the second conveying roller 6a. Therefore, the second driven roller 6b is composed of a so-called star wheel with irregularly shaped protrusions and depressions repeatedly arranged on its outer periphery in the circumferential direction. Of course, the second driven roller 6b is not limited to a star wheel and may also be a rubber roller. Furthermore, the first driven roller 5b is not limited to a rubber roller and may also be a star wheel.

[0051] In addition, the first conveying mechanism 5 and the second conveying mechanism 6 for conveying medium S are not limited to having mechanisms such as a first conveying roller 5a and a second conveying roller 6a. For example, medium S can also be conveyed by a belt or a drum.

[0052] The moving mechanism 7 is used to reciprocate the liquid injection head H in the Y-axis direction. The moving mechanism 7 includes a carriage 7a and a conveyor belt 7b. The carriage 7a is a generally box-shaped structure that houses the liquid injection head H and is fixed to the conveyor belt 7b. The conveyor belt 7b is a loop belt installed along the Y-axis direction. The conveyor belt 7b is rotated by a conveyor motor (not shown). The control unit 4 controls the rotation of the conveyor belt 7b by controlling the drive of the conveyor motor, causing the liquid injection head H and the carriage 7a to reciprocate together in the Y-axis direction along a guide rail (not shown). Additionally, the liquid storage unit 3 may also be mounted on the carriage 7a together with the liquid injection head H.

[0053] Under the control of the control unit 4, the liquid injection head H executes the injection from multiple nozzles 23 (see reference). Figure 3The ink supplied from the liquid storage unit 3 is ejected in the +Z direction as an ink droplet ejection action. The ink droplet ejection action of the liquid ejection head H is carried out in parallel with the reciprocating movement of the liquid ejection head H by the medium S transport and movement mechanism 7, which is the first transport mechanism 5 and the second transport mechanism 6, thereby performing a so-called printing action to form an ink image on the surface of the medium S.

[0054] Figure 3 This is an exploded perspective view of the liquid injection head H of this embodiment. Figure 4 This is a cross-sectional view of the liquid jet head H. Figure 5 This is a top view of the liquid jet head H viewed from the -Z direction. Figure 6 It is magnification Figure 4 A diagram of the main parts. Figure 7 This is a top view of the liquid jet head H and the medium S from the -Z direction. Figure 8 It shows based on Figure 7 A cross-sectional view of the contact state between the cover 30 of line AA′ and medium S. Figure 9 This is a top view of the liquid jet head H and the medium S of the comparative example, viewed from the -Z direction. Figure 10 It shows based on Figure 9 A cross-sectional view of the contact state between the cover 30 of the B-B′ line and the medium S.

[0055] like Figures 3-6 As shown, the head holder 11 constituting the liquid injection head H has a mounting portion 12 on the surface facing the +Z direction.

[0056] The head holder 11 has a plurality of ink passages 13, one end of which is open in each mounting portion 12 and the other end of which is open in the face facing the +Z direction. A portion of the +Z-direction side of each ink passage 13 is disposed inside a tubular flow path forming portion 14 that protrudes in the +Z-direction direction from the face of the head holder 11 facing the +Z direction.

[0057] At the opening of the ink passage 13 of the mounting portion 12 on the -Z direction side of the head holder 11, a flow path connection portion 15 having multiple hollow needle shapes is fixed to the supply pipe via a filter 16 for pre-positioning air bubbles and foreign objects in the ink. In addition, the flow path connection portion 15 is not limited to a needle shape, but may also be cylindrical.

[0058] Furthermore, the flow path connection portion 15 can be directly connected to a supply pipe, or it can be connected via other flow path components, such as a pressure adjustment mechanism that adjusts the pressure supplied from upstream to downstream. Additionally, a liquid storage unit 3, such as a box, can be directly mounted on the mounting portion 12. In other words, the flow path connection portion 15 can also be inserted into the liquid storage unit 3 mounted on the mounting portion 12.

[0059] On the face of the head retainer 11 facing the +Z direction, the head component 19 is fixed with the sealing component 17 and the circuit board 18 sandwiched between them.

[0060] The head component 19 includes: a hollow box-shaped component, namely a head housing 21, for housing a piezoelectric actuator unit 20 having multiple piezoelectric actuators, and a head body 22 on the opposite side of the head holder 11 fixed to the head housing 21, namely, the side facing the +Z direction.

[0061] The head body 22 includes: a nozzle plate 24, a flow path forming substrate 26, and a vibrating plate 27.

[0062] The nozzle plate 24 has a plurality of nozzles 23. In this embodiment, the nozzles 23 are arranged side by side in the X-axis direction, and eight rows of nozzles are arranged in the Y-axis direction. However, the arrangement of the nozzles 23 and the number of nozzle rows are not particularly limited thereto. Furthermore, the surface of the nozzle plate 24 facing the +Z direction is called the nozzle surface 24a. When viewed from the -Z direction, the shape of such a nozzle plate 24 is a rectangle or a roughly rectangular shape including a pair of sides 24b extending in the Y-axis direction and a pair of sides 24c extending in the X-axis direction. Here, "roughly rectangular" means a shape with corners chamfered to resemble a curved surface or a straight line, based on a rectangle viewed from the -Z direction.

[0063] The flow path forming substrate 26 has a flow path including a pressure chamber 25 communicating with the nozzle 23. The nozzle plate 24 is bonded to the surface of the flow path forming substrate 26 facing the +Z direction.

[0064] The vibrating plate 27 is fixed to the -Z direction facing surface of the flow path forming substrate 26. The nozzle plates 24, the vibrating plate 27, and the flow path forming substrate 26 are bonded together by adhesive.

[0065] Although not specifically illustrated, the piezoelectric actuator constituting the piezoelectric actuator unit 20 is, for example, a longitudinally vibrating actuator device that alternately layers piezoelectric material and electrode forming material and stretches and contracts along the axial direction. Such a piezoelectric actuator becomes a driving element that causes pressure changes in the ink within the pressure chamber 25.

[0066] Furthermore, the head housing 21 has an ink supply passage 28 that communicates with the pressure chamber 25 at one end and with the ink communication passage 13 of the head holder 11 at the other end. The connection between the ink communication passage 13 and the ink supply passage 28 is fluid-tightly connected by a sealing member 17 formed of rubber or the like.

[0067] In addition, the liquid injection head H has a cover 30. The cover 30 includes a frame portion 40 disposed along an XY plane defined by the X-axis and the Y-axis, and a side wall portion 50 disposed extending zigzagly from the frame portion 40 along the side of the head body 22.

[0068] When viewed from the -Z direction, the frame portion 40 has a rectangular or approximately rectangular shape. The frame portion 40 has an opening 41 that exposes the nozzles 23 of the nozzle plate 24 in the +Z direction. In this embodiment, the opening 41 is sized to expose all the nozzles 23 of the entire nozzle row in the +Z direction.

[0069] Furthermore, the frame portion 40 has a first edge portion 42 that covers the portion of the outer periphery of the nozzle surface 24a extending in the X-axis direction. Additionally, the frame portion 40 has a second edge portion 43 that covers the portion of the outer periphery of the nozzle surface 24a extending in the Y-axis direction. That is, when the cover 30 is viewed from the -Z direction, the first edge portion 42 covers portions of a pair of edges 24c extending in the X-axis direction of the outer periphery of the nozzle plate 24, and the second edge portion 43 covers portions of a pair of edges 24b extending in the Y-axis direction of the outer periphery of the nozzle plate 24. In other words, the cover 30 has a box shape that covers the entire outer periphery of the nozzle plate 24.

[0070] The opening 41 is defined by a first edge portion 42 and a second edge portion 43. Specifically, the first edge portion 42 has a first inner edge 44 that defines the inner edge of the opening 41. Furthermore, the second edge portion 43 has a second inner edge 45 that defines the inner edge of the opening 41. The first inner edge 44 is a portion having a vector along the X-axis direction, and is the inner edge on both sides of the opening 41 in the Y-axis direction. Moreover, the first inner edge 44 refers only to the portion located further in the +Z direction than the nozzle surface 24a. The second inner edge 45 is a portion provided along the Y-axis direction, and is the inner edge on both sides of the opening 41 in the X-axis direction. In this embodiment, the second inner edge 45, like the first inner edge 44, is located further in the +Z direction than the nozzle surface 24a. Moreover, the opening 41 is defined by this pair of first inner edges 44 and the pair of second inner edges 45.

[0071] The first inner edge 44 includes: a straight section 46 extending substantially parallel to the X-axis direction, two inclined sections 47 inclined relative to the straight section extending parallel to the X-axis direction, and two curved sections 48.

[0072] In this embodiment, the straight portion 46 is disposed at the center of the first inner edge 44 in the X-axis direction. In this invention, "center" includes the central portion when the first inner edge 44 is divided into three parts in the X-axis direction, and more preferably, the central portion when the first inner edge 44 is divided into five parts in the X-axis direction. Furthermore, "disposed at the center of the first inner edge 44 in the X-axis direction" means that a portion or all of the straight portion 46 is located in that central portion in the X-axis direction.

[0073] The inclined portion 47 and the straight portion 46 are adjacent to each other on both sides in the X-axis direction, that is, they are continuously arranged in such a way that they are connected to the straight portion 46 in the +X direction and the -X direction, respectively.

[0074] The curved portions 48 are respectively provided on opposite sides of the straight portions 46 of the two inclined portions 47 in the X-axis direction. That is, the curved portions 48 are continuously provided with the +X direction of the inclined portions 47 located in the +X direction of the straight portion 46 and the -X direction of the inclined portions 47 located in the -X direction of the straight portion 46. In addition, the two ends of the curved portions 48 in the X-axis direction are connected to the second inner edge 45. That is, the curved portions 48 are respectively provided at both ends of the first inner edge 44 in the X-axis direction.

[0075] Here, "approximately parallel" in this invention means less than 5 degrees relative to the X-axis direction. That is, the straight section 46 is set at an angle of less than 5 degrees relative to the X-axis direction. In addition, the inclined section 47 is inclined relative to a straight line parallel to the X-axis direction at an angle of more than 5 degrees relative to the X-axis direction.

[0076] The tilt angle of the inclined portion 47 relative to the X-axis direction is preferably 5 degrees or more and 15 degrees or less, more preferably 5 degrees or more and 10 degrees or less. In this embodiment, the tilt angle of the inclined portion 47 is 8 degrees.

[0077] Furthermore, the straight portion 46 is disposed on the outermost side of the first inner edge 44 in the Y-axis direction. That is, with the center of the nozzle plate 24 as observed in the Z-axis direction as a reference, the straight portion 46 is disposed on the outermost side in the Y-axis direction, an inclined portion 47 is disposed on the inner side of the straight portion 46 in the Y-axis direction, and a curved portion 48 is disposed on the inner side of the inclined portion 47 in the Y-axis direction. In other words, each inclined portion 47 is inclined toward the center in the X-axis direction to increase the width of the opening 41 in the Y-axis direction.

[0078] Furthermore, the combined length of the inclined portion 47 and the curved portion 48 in the X-axis direction is longer than 50% of the length L of the first inner edge 44 in the X-axis direction. In other words, the proportion of the two inclined portions 47 and the two curved portions 48 in the X-axis direction of the first inner edge 44—that is, the combined length of the two inclined portions 47 (2×L2) and the two curved portions 48 (2×L3) in the X-axis direction—is longer than 50% relative to the length L of the first inner edge 44 in the X-axis direction. In other words, the combined length of the inclined portions 47 and the curved portions 48 in the X-axis direction is longer than the length of the straight portion 46 in the X-axis direction. Specifically, the combined length L2 of each of the two inclined portions 47 and the length L3 of each of the curved portions 48 in the X-axis direction (2×L2+2×L3) is longer than the length L1 of the straight portion 46. That is, the length L1 of the straight part 46, the length L2 of the inclined part 47, and the length L3 of the curved part 48 satisfy the relationship (2×L2+2×L3)>L1.

[0079] Furthermore, the length L2 of an inclined portion 47 in the X-axis direction is preferably 25% or more and 40% or less than the length L of the first inner edge 44 in the X-axis direction. In this embodiment, the length L2 of an inclined portion 47 is 32% of the length L.

[0080] Furthermore, the proportion of the length of one or more straight portions 46 located at the same position in the Y-axis direction relative to the length L of the first inner edge 44 in the X-axis direction is less than 50%, preferably 30% or less, and more preferably 10% or less. In this embodiment, the proportion of the length L1 of the straight portion 46 relative to the length L of the first inner edge 44 is approximately 13%. Additionally, the proportion of the straight portion 46 refers to the proportion of the length L1 of the straight portion 46 in the X-axis direction. As in this embodiment, when there is only one straight portion 46, it is the proportion of the length L1 of the straight portion 46 relative to the length L of the first inner edge 44. Furthermore, although not illustrated in this embodiment, when multiple straight portions 46 are provided, the proportion of the straight portions 46 located at the same position in the Y-axis direction refers to the proportion of the total length of the multiple straight portions 46 located at the same position in the Y-axis direction relative to the length L of the first inner edge 44.

[0081] The sidewall portion 50 extends from the frame portion 40 at the outer periphery of the nozzle surface 24a of the liquid injection head H, on the side surface of the nozzle surface 24a. The sidewall portion 50 has a flange portion 51, which is provided with a fixing hole 51a for fixing the cover 30 to the head housing 21. The flange portion 51 is bent outward in the Y-axis direction from the sidewall portion 50 in the same direction as the surface direction of the nozzle surface 24a.

[0082] Furthermore, on the +Z direction facing surface of the head holder 11, a sealing member 17, a circuit board 18, a head housing 21 constituting the head component 19, and a head body 22 are sequentially arranged, with a cover 30 arranged to cover the ends of the head body 22 and the head housing 21 in the +Z direction. In this state, the cover 30 is fixed to the head holder 11 using screws 52, forming a liquid jet head H. That is, in this embodiment, the components constituting the liquid jet head H are fixed to each other by inserting screws 52 through the fixing hole 51a of the cover 30, the first insertion hole 21a of the head housing 21, and the second insertion hole 18a of the circuit board 18 and screwing them into the head holder 11. Of course, the cover 30 can also be fixed to the head housing 21 with screws 52, and other screws can be provided to fix the head housing 21 to the head holder 11. Thus, in this embodiment, the cover 30 is fixed to the head housing 21 and the head body 22 without adhesive. Therefore, it is possible to suppress warping or damage caused by warping of the cover 30 and components constituting the head housing 21 and head body 22 due to differences in their coefficients of linear expansion during temperature changes, such as the nozzle plate 24 and the flow path forming substrate 26. In other words, if the cover 30 is bonded to materials with different coefficients of linear expansion, such as the head housing 21 and head body 22, warping or damage will occur due to expansion and contraction caused by temperature changes. Furthermore, if the cover 30 is bonded to the head housing 21 and head body 22 with adhesive, undesirable conditions such as nozzle plate 24 peeling may occur due to the stress caused by the collision between the medium S and the cover 30. In this embodiment, the cover 30 is fixed to the head housing 21 and head body 22 without adhesive, thereby suppressing damage such as nozzle plate 24 peeling caused by differences in coefficients of linear expansion and the collision between the medium S and the cover 30.

[0083] Such a cover 30 is formed by stamping a thin sheet of metal such as stainless steel. If the cover 30 is too thick, the distance between the nozzle surface 24a and the medium S in the X-axis direction increases, making it easier for ink droplets ejected from the nozzle 23 to deviate from their landing position on the medium S. Furthermore, if the cover 30 is too thin, its rigidity decreases, and it cannot effectively protect the head component 19 from impacts by the medium S. Therefore, the thickness of the cover 30 is preferably 0.1 mm to 0.2 mm.

[0084] Here, the medium S sometimes bends and floats off the support member 8 due to slack and warping caused by ink falling between the first conveying mechanism 5 and the second conveying mechanism 6. Therefore, when the medium S is floating off the support member 8, if the carriage 7a carrying the liquid jet head H is moved in the Y-axis direction, the first edges 42 of the cover 30 of the liquid jet head H on both sides in the Y-axis direction may come into contact with the Y-axis ends of the floating medium S. At this time, if... Figure 9As shown, if the straight portion 46 of the first inner edge 44 occupies a large proportion, that is, if the straight portion 46 is more than 50%, then as Figure 10 As shown, the raised media S abuts against the straight portion 46 of the first inner edge 44 in a state where its end face in the Y-axis direction is parallel to the straight portion 46. Furthermore, the area of ​​the media S in simultaneous contact with the first inner edge 44 in the Y-axis direction increases. Therefore, the media S easily enters between the first edge 42 of the cover 30 and the nozzle surface 24a, and is easily jammed by the first edge 42, thus easily causing a paper jam. Furthermore, if the straight portion is 50% or more, the raised media S collides or jams due to line contact with the first edge 42, thus easily causing damage to the first edge 42 of the cover 30. Moreover, when the first edge 42 of the cover 30 is flipped up, the media S is more likely to get stuck on it, making a paper jam more likely.

[0085] In contrast, in this embodiment, such as Figure 7 as well as Figure 8 As shown, the proportion of the straight portion 46 of the first inner edge 44 is less than 50%. By providing an inclined portion 47 and a curved portion 48 on the first inner edge 44, the medium S floating from the support member 8 abuts against the inclined portion 47 and the curved portion 48. Therefore, the inclined portion 47 and the curved portion 48 of the cover 30 abut at an angle relative to the end face of the medium S in the Y-axis direction, and the area of ​​simultaneous contact between the end face of the medium S and the first inner edge 44 can be reduced. Therefore, the floating medium S is less likely to enter between the first edge 42 of the cover 30 and the nozzle surface 24a, and the occurrence of paper jams caused by the medium S being stuck by the first edge 42 can be reduced. In addition, since the end face of the medium S abuts against the first inner edge 44 at an angle, that is, a point contact is made, the impact during contact can be released. As a result, the possibility of the first edge 42 being damaged by flipping up can be reduced. Furthermore, since the first edge 42 can be suppressed from flipping up due to the floating medium S, the occurrence of paper jams caused by the medium S being further stuck by the flipped first edge 42 can be reduced.

[0086] Furthermore, in this embodiment, by providing the straight portion 46, the angle between the inclined portion 47 and the straight portion 46 can be reduced compared to the case where the two inclined portions 47 are directly connected to each other when viewed in the -Z direction. That is, for example, when the inclined portion 47 is inclined at 8 degrees relative to the X-axis direction, in this embodiment, the angle between the straight portion 46 and the inclined portion 47 is 8 degrees. In contrast, if the straight portion 46 is not provided, the inclined portions 47 are directly connected to each other, and therefore the angle between the two inclined portions 47 becomes larger, at 16 degrees. As described above, the cover 30 is formed by stamping a metal sheet. Therefore, during stamping, if the angle at the corner is large, stress concentrates at the corner, and the flatness of the frame portion 40 decreases. In this embodiment, by providing the straight portion 46, during stamping, the angle between the straight portion 46 and the inclined portion 47 is reduced, making it less likely for stress to concentrate at the corner, thus improving the flatness of the frame portion 40. Furthermore, in this embodiment, by providing a straight portion 46 and dividing the inclined portion 47 into two parts, the maximum width of the first edge portion 42 in the Y-axis direction can be reduced compared to the case where an inclined portion 47 is provided on a first inner edge 44.

[0087] Furthermore, because the straight portion 46 is positioned on the outermost side of the first inner edge 44 in the X-axis direction, the medium S is less likely to enter the gap between the straight portion 46 and the nozzle surface 24a compared to the case where the straight portion 46 is positioned on the innermost side in the X-axis direction. In other words, for example, if the straight portion 46 is positioned on the innermost side in the X-axis direction, the first inner edge 44 will appear convex towards the inner side in the X-axis direction when viewed from the -Z direction. Thus, if the first inner edge 44 is convex, the medium S is easily caught by the convex front portion, i.e., the straight portion 46, and easily enters the gap between the straight portion 46 and the nozzle surface 24a. In this embodiment, by positioning the straight portion 46 on the outermost side in the X-axis direction, the first inner edge 44 is formed as concave. Therefore, compared to the case where it is convex, in this embodiment, the medium S is less likely to enter the gap between the straight portion 46 and the nozzle surface 24a in the first inner edge 44.

[0088] Furthermore, in this embodiment, the cover 30 is provided in contact with the outer peripheral edge of the nozzle plate 24. Specifically, as... Figure 6As shown, the first edge 42 of the frame portion 40 of the cover 30 has an abutment portion 42a on the sidewall portion 50 facing the -Z direction opposite to the nozzle surface 24a, which contacts the outer peripheral edge of the nozzle plate 24. Furthermore, the frame portion 40 extends from the abutment portion 42a toward the first inner edge 44 away from the nozzle plate 24. That is, the frame portion 40 is inclined relative to the nozzle surface 24a toward the +Z direction from the abutment portion 42a toward the first inner edge 44. Thus, by extending the first edge 42 away from the nozzle plate 24 from the abutment portion 42a toward the first inner edge 44, the abutment portion 42a can reliably contact the nozzle plate 24, enabling stable communication between the nozzle plate 24 and the cover 30, thereby grounding the nozzle plate 24 via the cover 30. In this way, by grounding the nozzle plate 24, the influence of the charged medium S on the liquid injection head H can be suppressed, particularly damage caused by charging. Therefore, in order to ground the nozzle plate 24 via the cover 30, even if the distance between the first inner edge 44 and the nozzle surface 24a in the Z-axis direction is relatively wide, by providing the straight portion 46, the inclined portion 47, and the curved portion 48 in the above proportions on the first inner edge 44, the medium S is less likely to enter between the first edge 42 of the cover 30 and the nozzle surface 24a, and paper jams and the lifting of the first edge 42 caused by the medium S can be suppressed. In other words, in order to conduct the connection between the cover 30 and the nozzle plate 24, it is not necessary to increase the number of parts or to construct a large scale.

[0089] Furthermore, in the configuration where the first edge portion 42 extends from the abutment portion 42a toward the first inner edge 44 away from the nozzle surface 24a, as described above, by providing the straight portion 46 to divide the inclined portion 47 into two, the maximum width of the first edge portion 42 in the Y-axis direction can be reduced. In other words, by providing the straight portion 46 to divide the inclined portion 47 into two, and making the inclination directions of the two inclined portions 47 different, the maximum width of the first edge portion 42 in the Y-axis direction can be reduced. Moreover, by reducing the maximum width of the first edge portion 42 in the Y-axis direction, the gap between the first inner edge 44 and the nozzle surface 24a in the Z-axis direction can be reduced. Therefore, the medium S is less likely to enter between the first edge portion 42 and the nozzle surface 24a.

[0090] In addition, in this embodiment, the second inner edge 45 extends substantially parallel in the Y-axis direction. Of course, the second inner edge 45, like the first inner edge 44, may also have a straight portion 46, an inclined portion 47, and a curved portion 48.

[0091] Furthermore, in this embodiment, the Y-axis direction is an example of a "first direction," and the X-axis direction is an example of a "second direction." Additionally, the inclined portion 47 and the curved portion 48 are examples of "first portions that do not extend substantially parallel to the second direction," and the straight portion 46 is an example of a "second portion." That is, the "first portion" is the portion defining the first inner edge 44 that is a straight portion that does not extend substantially parallel to the "second direction" (equivalent to the "second portion" in this embodiment).

[0092] Alternatively, the curved portion 48 may not be provided on the first inner edge 44, in which case the "first part" is composed only of the inclined portion 47. Similarly, the inclined portion 47 may not be provided on the first inner edge 44, in which case the "first part" is composed only of the curved portion 48.

[0093] In this embodiment, the length L of the straight portion 46 relative to the first inner edge 44 accounts for approximately 13%, but it is not particularly limited to this; the proportion of the straight portion 46 may be less than 50%. Figure 11 This indicates the case where the straight portion 46 occupies 46% of the length L of the first inner edge 44. Additionally, Figure 11 This is a top view of the liquid injection head H of the modified embodiment 1, viewed from the -Z direction.

[0094] like Figure 11 As shown, the first inner edge 44 includes: a straight portion 46 disposed at the center in the X-axis direction, inclined portions 47 respectively disposed on both sides of the straight portion 46 in the X-axis direction, and curved portions 48 disposed on the opposite side of the straight portion 46 in the X-axis direction for each inclined portion 47.

[0095] The length L1 of the straight portion 46 is set to 46% of the length L of the first inner edge 44. That is, the combined length of the two inclined portions 47 and the two curved portions 48 in the X-axis direction is approximately 54% of the length L of the first inner edge 44.

[0096] Even with this configuration, since the portion of the first inner edge 44 that is longer than 50% is composed of the inclined portion 47 and the curved portion 48, similarly to Embodiment 1 described above, the medium S is less likely to enter between the cover 30 and the nozzle surface 24a, thus suppressing paper jams and preventing the first edge 42 of the cover 30 from flipping up.

[0097] In addition, in a variation of Embodiment 1, similar to Embodiment 1, the Y-axis direction is a "first direction" and the X-axis direction is a "second direction". Furthermore, the inclined portion 47 and the curved portion 48 are examples of "first portions that do not extend substantially parallel to the second direction", and the straight portion 46 is an example of "second portions".

[0098] Implementation Method 2

[0099] Figure 12 This is a top view of the liquid injection head H according to Embodiment 2, viewed from the -Z direction. Furthermore, the same reference numerals are used for components identical to those in Embodiment 1, and repeated descriptions are omitted.

[0100] like Figure 12 As shown, the liquid injection head H of this embodiment has the same configuration as that of Embodiment 1, except for the shape of the opening 41 of the cover 30. The first inner edge 44 of the first edge 42 of the cover 30 of this embodiment includes two inclined portions 47 with different inclination angles, and two curved portions 48 provided on both sides of the two inclined portions 47 in the X-axis direction.

[0101] The ends of the two inclined portions 47 are connected to each other. That is, the first inner edge 44 of this embodiment does not have the straight portion 46 of Embodiment 1. In other words, the proportion of the length L of the straight portion 46 relative to the length L of the first inner edge 44 in the X-axis direction of this embodiment is less than 50%. That is, the proportion of the length L of the straight portion 46 relative to the length L of the first inner edge 44 in the X-axis direction is less than 50%, and also includes 0%. Moreover, in this embodiment, since the straight portion 46 of Embodiment 1 is not provided, the total length (2×L2+2×L3) of the two inclined portions 47 and the two curved portions 48 in the X-axis direction is longer than 50% of the length L of the first inner edge 44 in the X-axis direction. In other words, in this embodiment, it is longer than the length of the straight portion in the X-axis direction, which is 0 (zero).

[0102] The two inclined portions 47 are inclined toward the center in the X-axis direction to widen the opening 41 in the Y-axis direction, that is, the first inner edge 44 is concave. In addition, the inclination angle and length of these inclined portions 47, as well as the length of the curved portion 48, are the same as in Embodiment 1 described above.

[0103] Even with this configuration, similar to Embodiment 1 described above, even if the medium S floats up from the support member 8, the medium S is not likely to enter between the nozzle surface 24a and the first edge 42, thus preventing paper jams and preventing the first edge 42 from being flipped up by the medium S.

[0104] Furthermore, in Embodiment 2, the Y-axis direction is an example of a "first direction," and the X-axis direction is an example of a "second direction." Additionally, the inclined portion 47 and the curved portion 48 are examples of "first portions that do not extend substantially parallel to the second direction."

[0105] Implementation Method 3

[0106] Figure 13This is a top view of the liquid injection head H according to Embodiment 3, viewed from the -Z direction. Furthermore, the same reference numerals are used for components identical to those in Embodiment 1, and repeated descriptions are omitted.

[0107] like Figure 13 As shown, the liquid injection head H of this embodiment has the same configuration as that of Embodiment 1, except for the shape of the opening 41 of the cover 30. The first inner edge 44 of the first edge 42 of the cover 30 in this embodiment has only one curved portion 48. That is, the first inner edge 44 does not have the straight portion 46 and the inclined portion 47 of Embodiment 1.

[0108] The curved portion 48 is formed such that, when viewed from the -Z direction, it is formed as a concave surface toward the nozzle 23.

[0109] The length L3 of the curved portion 48 in the X-axis direction is longer than 50% of the length L of the first inner edge 44 in the X-axis direction. That is, the ratio of the length L3 of the curved portion 48 in the X-axis direction to the length L of the first inner edge 44 in the X-axis direction is greater than 50%. This ratio is more preferably 70% or more, and more preferably 90% or more. Furthermore, the ratio of the length L1 of the straight portion 46 in the X-axis direction to the length L of the first inner edge 44 in the X-axis direction is less than 50%, more preferably 30% or less, and more preferably 10% or less. Alternatively, as in this embodiment, the length of the straight portion 46 may be 0 (zero), and the ratio of the length L3 of the curved portion 48 in the X-axis direction to the length L of the first inner edge 44 in the X-axis direction may be 100%. That is, in this embodiment, the length L3 of the curved portion 48 in the X-axis direction is equal to the length L of the first inner edge 44 in the X-axis direction.

[0110] Even with this configuration, similar to Embodiment 1 described above, even if the medium S floats up from the support member 8, the medium S is not likely to enter between the nozzle surface 24a and the first edge 42, thus preventing paper jams and preventing the first edge 42 from being flipped up by the medium S.

[0111] Furthermore, in Embodiment 3, there is an example where the Y-axis direction is the "first direction" and an example where the X-axis direction is the "second direction". Additionally, the curved portion 48 is an example where it is a "first portion that does not extend substantially parallel to the second direction".

[0112] Implementation Method 4

[0113] Figure 14 This is a top view of the liquid injection head H according to Embodiment 4, viewed from the -Z direction. Furthermore, the same reference numerals are used for components identical to those in Embodiment 1, and repeated descriptions are omitted.

[0114] like Figure 14As shown, the liquid injection head H of this embodiment has the same configuration as that of Embodiment 1, except for the shape of the opening 41 of the cover 30. The first inner edge 44 of the first edge 42 of the cover 30 in this embodiment includes: an inclined portion 47 disposed at the center in the X-axis direction, and two curved portions 48 disposed on both sides of the inclined portion 47 in the X-axis direction. That is, the first inner edge 44 does not have the straight portion 46 of Embodiment 1. In other words, the proportion of the straight portion 46 relative to the length L of the first inner edge in the X-axis direction of this embodiment is less than 50%. That is, the proportion of the straight portion 46 relative to the length L of the first inner edge 44 in the X-axis direction is less than 50%, and includes 0%. Moreover, in this embodiment, since the straight portion 46 of Embodiment 1 is not provided, the total length of the inclined portion 47 and the two curved portions 48 in the X-axis direction (L2+2×L3) is longer than 50% of the length L of the first inner edge 44 in the X-axis direction. In other words, in this embodiment, it is longer than the length of the straight portion in the X-axis direction, which is 0 (zero).

[0115] The tilt angles and total lengths of these tilted portions 47, as well as the lengths of the bent portions 48, are the same as in Embodiment 1 described above.

[0116] Furthermore, the inclined portions 47 of the first inner edges 44 respectively provided on both sides in the Y-axis direction are inclined in different directions such that the width of the opening 41 in the Y-axis direction increases as it moves toward the +X direction. Of course, the inclined portions 47 of the first inner edges 44 respectively provided on both sides in the X-axis direction can also be parallel to each other, so that the width of the opening 41 in the Y-axis direction is approximately the same along the X-axis direction. That is, the opening 41 can also be set to be a parallelogram when viewed from the -Z direction. However, even if the opening 41 of the cover 30 is a parallelogram, as described above, the nozzle plate 24 has a rectangular or approximately rectangular shape.

[0117] Even with this configuration, similar to Embodiment 1 described above, even if the medium S floats up from the support member 8, the medium S is not likely to enter between the nozzle surface 24a and the first edge 42, thus preventing paper jams and preventing the first edge 42 from being flipped up by the medium S.

[0118] Furthermore, in Embodiment 4, the Y-axis direction is an example of a "first direction," and the X-axis direction is an example of a "second direction." Additionally, the inclined portion 47 and the curved portion 48 are examples of "first portions that do not extend substantially parallel to the second direction."

[0119] Implementation Method 5

[0120] Figure 15This is a top view of the liquid injection head H according to Embodiment 5, viewed from the -Z direction. Furthermore, the same reference numerals are used for components identical to those in Embodiment 1, and repeated descriptions are omitted.

[0121] like Figure 15 As shown, the liquid injection head H of this embodiment has the same configuration as that of Embodiment 1, except for the shape of the opening 41 of the cover 30. The first inner edge 44 of the first edge 42 of the cover 30 of this embodiment includes: a plurality of straight portions 46 arranged offset in the X-axis direction, three in this embodiment; two inclined portions 47 connecting two straight portions 46 to each other; and two curved portions 48 provided at both ends of the first inner edge 44 in the X-axis direction.

[0122] Three straight sections 46 extend substantially parallel to each other in the X-axis direction. Each of the three straight sections 46 includes: a first straight section 46a disposed at the center of the first inner edge 44 in the X-axis direction, and two second straight sections 46b disposed on either side of the first straight section 46a in the X-axis direction via inclined portions 47. The second straight sections 46b are disposed at the same position in the Y-axis direction and have the same length in the X-axis direction. Hereinafter, without distinguishing between the first straight section 46a and the second straight section 46b, they will be referred to as straight sections 46.

[0123] The curved portion 48 is continuously provided on the opposite side of the inclined portion 47 in the X-axis direction of the second straight portion 46b.

[0124] The inclined portion 47 is inclined relative to a straight line extending parallel to the X-axis direction.

[0125] The inclination angles of the straight section 46 and the inclined section 47 relative to the X-axis direction are the same as those specified in Embodiment 1 above.

[0126] The length of the straight portion 46 located at the same position in the Y-axis direction relative to the length L of the first inner edge 44 in the X-axis direction is less than 50%, preferably 30% or less, and more preferably 10% or less. In this embodiment, the straight portion 46 located at the same position in the Y-axis direction refers to the first straight portion 46a or two second straight portions 46b. That is, the length L4 of the first straight portion 46a is less than 50% of the length L of the first inner edge 44. Furthermore, the total length of the two second straight portions 46b in the X-axis direction (2×L5) is less than 50% of the length L of the first inner edge 44.

[0127] Even with this configuration, similar to Embodiment 1 described above, even if the medium S floats up from the support member 8, the medium S is not likely to enter between the nozzle surface 24a and the first edge 42, thus preventing paper jams and preventing the first edge 42 from being flipped up by the medium S.

[0128] In addition, in embodiment 5, there is an example where the Y-axis direction is the "first direction" and the X-axis direction is the "second direction".

[0129] Implementation Method 6

[0130] Figure 16 This is a top view of the liquid injection head H according to Embodiment 6, viewed from the -Z direction. Furthermore, the same reference numerals are used for components identical to those in Embodiment 1, and repeated descriptions are omitted.

[0131] like Figure 16 As shown, the liquid injection head H of this embodiment has the same configuration as that of Embodiment 1, except for the shape of the opening 41 of the cover 30. The first inner edge 44 of the first edge 42 of the cover 30 of this embodiment includes: two inclined portions 47 that are inclined relative to the X-axis direction in different directions and are provided in the central portion in the X-axis direction; two straight portions 46 that are respectively provided on both sides of the inclined portions 47 in the X-axis direction; and two curved portions 48 that are respectively provided on the opposite side of the inclined portions 47 of the straight portions 46 in the X-axis direction.

[0132] Here, the "central part" in this utility model refers to the central part that divides the first inner edge 44 into three parts, more preferably the central part that divides it into five parts.

[0133] The inclined portion 47 is inclined relative to a straight line extending parallel to the X-axis direction. In this embodiment, on a first inner edge 44, two inclined portions 47 are arranged such that their ends are connected to each other to form a recess.

[0134] The straight section 46 and the two inclined sections 47 are adjacent to each other on both sides of the X-axis direction, that is, they are continuously arranged in such a way that they are connected to the +X direction and -X direction of the inclined section 47 respectively.

[0135] The curved portions 48 are respectively provided on opposite sides of the inclined portions 47 of the two straight portions 46. Similar to Embodiment 1 described above, the inclined portions 47 are inclined relative to the straight lines parallel to the X-axis direction.

[0136] In addition, in this embodiment, two inclined portions 47 are provided in the central portion of each first inner edge 44, but it is not particularly limited to this, and a curved portion forming a concave surface may also be provided.

[0137] Here, the medium S floating from the support member 8 easily comes into contact with the central portion of the first inner edge 44 in the X-axis direction. Since the central portion of the first edge 42 in the X-axis direction is far from the second edge 43, its rigidity is relatively low. Therefore, by providing the inclined portion 47 in the central portion of the first inner edge 44 in the X-axis direction, the medium S floating from the support member 8 is less likely to enter between the nozzle surface 24a and the first edge 42, thus suppressing paper jams and preventing the first edge 42 from being flipped up by the medium S. Furthermore, in Embodiment 6, the Y-axis direction is an example of a "first direction," and the X-axis direction is an example of a "second direction."

[0138] Other implementation methods

[0139] The various embodiments of this utility model have been described above, but the basic structure of this utility model is not limited to the above-described structure.

[0140] For example, in the embodiments described above, the cover 30 is shown to cover the entire outer periphery of the nozzle plate 24, but it is not particularly limited to this; the cover 30 may also cover at least a portion. For example, the second inner edge of the cover 30 may be located further outward in the X-axis direction than one edge 24c of the nozzle surface 24a, and the second inner edge may also be located further in the -Z direction than the nozzle surface 24a. In this configuration, a portion of the inner edge of the opening 41 connected to the second inner edge on both sides in the Y-axis direction is also located further in the -Z direction than the nozzle surface 24a, and the first inner edge 44 refers to the portion of the inner edge on both sides in the Y-axis direction located further in the +Z direction than the nozzle surface 24a. That is, the collision of the medium S with the cover 30 occurs in the portion located further in the +Z direction than the nozzle surface 24a of the cover 30. Therefore, by setting the first inner edge 44 to the configuration described in the embodiments above, deformation of the cover 30 and paper jams caused by the collision of the medium S can be suppressed.

[0141] Furthermore, in the above embodiments, a serial printer is exemplified as the liquid jetting device 1, but it is not particularly limited to this. It can also be a so-called line printer in which ink is jetted / falls onto the medium S from the liquid jetting head H while the liquid jetting head H is fixed in the printing process. Figure 17 This is a diagram showing a schematic configuration of the liquid injection device 1 according to other embodiments. (Refer to...) Figure 17 An example of a liquid jetting device 1 used in a line printer will be described. Furthermore, components identical to those in Embodiment 1 described above will be labeled with the same reference numerals, and repeated descriptions will be omitted.

[0142] like Figure 17 As shown, the liquid injection device 1 includes: a linear head LH equipped with at least one liquid injection head H, a liquid storage unit 3, a control unit 4, a first conveying mechanism 5 for conveying medium S, and a device body 9.

[0143] The liquid injection head LH extends along the X-axis. In this embodiment, it includes a liquid injection head H and a support body 100 that supports the liquid injection head H.

[0144] A liquid injection head H is supported by a support body 100. Of course, the number of liquid injection heads H constituting the row head LH is not limited to one; it can be two or more. Furthermore, multiple liquid injection heads H can also be arranged in a staggered configuration along the X-axis. Here, a staggered configuration of multiple liquid injection heads H means that the liquid injection heads H arranged side-by-side along the X-axis are alternately staggered in the Y-axis direction. That is, two columns of liquid injection heads H arranged side-by-side along the X-axis are arranged side-by-side along the Y-axis, and the columns of the two liquid injection heads H are staggered in the X-axis direction. In this way, by arranging the liquid injection heads H in a staggered configuration along the X-axis, the nozzles of two liquid injection heads H can partially overlap in the X-axis direction, forming a continuous column of nozzles in the X-axis direction. Of course, multiple liquid injection heads H can also be configured in a matrix.

[0145] The support body 100 supporting the liquid injection head H is fixed to the main body 9 of the device. Here, the liquid injection head H is configured such that the nozzles constituting the nozzle array are arranged side by side in the same direction as the X-axis. That is, the liquid injection head H is configured such that the first edge 42 forms the opening 41 on both sides in the Y-axis direction, and the second edge 43 forms the opening 41 on both sides in the X-axis direction.

[0146] This type of jet head LH has nozzles arranged across the entire width of the medium S in the X-axis direction. That is, in this embodiment, the multiple nozzles of the liquid jet head H are arranged across a width greater than the width of the medium S in the X-axis direction. As described above, by arranging the liquid jet heads H in a staggered manner in the X-axis direction, nozzles can be arranged across the entire width of the medium S, which is relatively wide in the X-axis direction.

[0147] The first conveying mechanism 5 conveys the medium S to the line head LH along the Y-axis direction. Furthermore, when the medium S is conveyed from the first conveying mechanism 5 in the +Y direction, the end of the medium S in the +Y direction contacts the first inner edge 44. Similarly, when the medium S is conveyed from the first conveying mechanism 5 in the -Y direction, the end of the medium S in the -Y direction contacts the first inner edge 44. In this case, by configuring the first inner edge 44 as described in embodiments 1 to 6, it is possible to suppress the floating medium S from entering the gap between the first edge 42 and the nozzle surface 24a, thereby reducing paper jams. Furthermore, the contact between the medium S and the first inner edge 44 prevents damage caused by the flipping of the first inner edge 44. Additionally, in... Figure 17 In the example shown, the Y-axis direction is an example of the "first direction", and the X-axis direction is an example of the "second direction".

[0148] Furthermore, in the above embodiments, a longitudinal vibration type actuator device that alternately layers piezoelectric material and electrode forming material and stretches and contracts axially was described as the driving element for generating pressure changes in the pressure chamber 25. However, the driving element is not limited to this. For example, a flexural vibration type actuator device can be used, such as a thin film type formed by laminating electrodes and piezoelectric materials through film deposition and photolithography, or a thick film type formed by adding green sheets. In addition, as a driving element, a device that arranges a heating element in the pressure chamber 25 and ejects droplets from the nozzle 23 by bubbles generated by the heating element, or a so-called electrostatic actuator that generates static electricity between the vibrating plate and the electrode and ejects droplets from the nozzle 23 by deforming the vibrating plate through electrostatic force.

[0149] Furthermore, this invention broadly targets all liquid jetting devices equipped with liquid jet heads. Examples of liquid jet heads include various inkjet recording heads used in image recording devices such as printers, and pigment jet heads used in the manufacture of color filters for liquid crystal displays. In addition, examples of liquid jet heads include electrode material jet heads used for electrode formation in organic EL displays, FED (field emission display), and bio-organic material jet heads used in the manufacture of biochips, and these liquid jet heads can also be applied to liquid jetting devices equipped with these liquid jet heads.

[0150] Postscript

[0151] Based on the examples above, understand the following components, for instance.

[0152] The preferred form, namely form 1, of the liquid injection head comprises: a nozzle plate having a nozzle face having a plurality of nozzles for injecting liquid along the injection direction; and a cover having an opening that exposes a portion of the nozzle face when viewed from the opposite direction of the injection direction, and the cover covering at least a portion of the outer periphery of the nozzle face. When viewed from the injection direction, the nozzle plate is rectangular or substantially rectangular in shape, including a pair of sides extending in a first direction and a pair of sides extending in a second direction orthogonal to the first direction. The cover has a first edge covering the portion of the outer periphery of the nozzle face extending in the second direction. The first edge has a first inner edge defining the inner edge of the opening. The first inner edge has a first portion extending not substantially parallel to the second direction, and the length of the first portion in the second direction is greater than 50% of the length of the first inner edge in the second direction. Therefore, because the straight portion provided at the first inner edge is shorter, the medium is less likely to get stuck in the gap between the first edge and the nozzle face when it comes into contact with the first portion extending not substantially parallel to the second direction, i.e., the first portion having at least one of an inclined portion or a curved portion. Therefore, it can reduce paper jams and damage caused by the media entering the gap, such as the first edge flipping up.

[0153] In a specific example of form 1, namely form 2, when viewed from the opposite direction of the spray direction, the first inner edge has a straight second portion disposed at the center of the first inner edge in the second direction and extending substantially parallel to the second direction. The first portion has two inclined portions adjacent to the two sides of the second portion and inclined relative to the second direction, respectively. Therefore, compared to connecting the ends of the two inclined portions to each other, connecting the two inclined portions via the straight portion reduces the angle of the formed corner, suppresses warping caused by stress concentration at the corner during manufacturing, and improves the flatness of the cap. Furthermore, by dividing the inclined portion into two parts, compared to forming a single inclined portion on the first inner edge, the maximum width of the first edge in the first direction can be reduced. This shortens the gap between the first inner edge and the nozzle surface, suppressing the entry of the medium into this gap.

[0154] In a specific example of form 2, namely form 3, the first part has two curved portions that are respectively disposed at both ends in the second direction of the first inner edge and are curved. Thus, by providing curved portions and avoiding the formation of acute angles at corners, warping caused by stress concentration at the corners during manufacturing can be suppressed, thereby improving the flatness of the cover.

[0155] In a specific example of form 1, namely form 4, the first inner edge has a straight second portion extending substantially parallel to the second direction, the second portion being disposed on the outermost side of the first inner edge in the first direction. Thus, by disposing the second portion on the outermost side of the first inner edge in the first direction, compared to disposing the second portion on the innermost side of the first direction, the medium S is less likely to enter the gap between the second portion and the nozzle surface.

[0156] In a specific example of form 2, namely form 5, the tilt angle of the inclined portion relative to the second direction is 5 to 10 degrees, and the ratio of the length of the inclined portion in the second direction to the length of the first inner edge in the second direction is 25% to 40%. Thus, by providing the first portion within this range, paper jams and warping of the first edge caused by the medium S entering between the first inner edge and the nozzle surface can be reduced.

[0157] In a specific example of form 1, namely form 6, the liquid jet head sprays liquid along the jetting direction while moving relative to the medium in the first direction.

[0158] In a specific example of form 1, namely form 7, the edge of the nozzle plate extending in the second direction contacts the abutting portion of the first edge of the cover. When viewed from the second direction, the first edge extends from the abutting portion toward the first inner edge of the cover in a manner away from the nozzle plate. This allows the nozzle plate to be connected to the cover, thereby grounding the nozzle plate via the cover. Furthermore, by tilting the first edge for grounding the nozzle plate, even if the distance between the first inner edge and the nozzle surface widens, media is less likely to enter between the cover and the nozzle surface, suppressing paper jams and the lifting of the first edge.

[0159] The preferred form, namely form 8, involves a liquid injection head that ejects liquid along an injection direction while moving relative to the medium in a first direction. It comprises: a nozzle plate having a nozzle surface with a plurality of nozzles for ejecting liquid; and a cover having an opening that exposes a portion of the nozzle surface when viewed from the opposite direction of the injection direction, and covering at least a portion of the outer periphery of the nozzle surface. The cover has a first edge covering a portion of the outer periphery of the nozzle surface extending in a second direction orthogonal to the first direction. The first edge has a first inner edge defining the inner edge of the opening. The proportion of one or more straight segments that are located at the same position in the first direction, define the first inner edge, and extend substantially parallel to the first inner edge in the second direction, relative to the length of the first inner edge in the second direction, is less than 50%. This proportion is preferably 30% or less, more preferably 10% or less. Alternatively, this proportion can be 0%. Therefore, since the straight segments provided at the first inner edge are relatively short, the medium is less likely to get stuck in the gap between the first edge and the nozzle surface. Therefore, it can reduce paper jams and damage caused by the media entering the gap, such as the first edge flipping up.

[0160] In a specific example of form 8, namely form 9, the first inner edge has at least one of an inclined portion that is inclined relative to a straight line parallel to the second direction and a curved portion. Thus, by contacting the inclined portion and the curved portion, the medium is less likely to enter between the first edge and the nozzle surface.

[0161] In a specific example of form 8, namely form 10, the first inner edge has a first portion extending not substantially parallel to the second direction, and the length of the first portion in the second direction is greater than 50% of the length of the first inner edge in the second direction. Therefore, by providing a first portion consisting of at least one of an inclined portion and a curved portion within the aforementioned range, the medium is less likely to enter the gap between the first edge and the nozzle surface, thus suppressing paper jams and warping of the first edge. Furthermore, this ratio is preferably 70% or more, more preferably 90% or more. Alternatively, this ratio can be 100%, i.e., no straight portion is provided on the first inner edge.

[0162] In a specific example of form 8, namely form 11, when viewed from the opposite direction of the jetting direction, the nozzle plate is rectangular or approximately rectangular in shape, comprising a pair of sides extending in the first direction and a pair of sides extending in the second direction.

[0163] In a specific example of form 8, namely form 12, the first inner edge has a plurality of straight sections that are staggered in the first direction and define the first inner edge and extend substantially parallel in the second direction.

[0164] The preferred form, namely the liquid jet head of form 13, is a liquid jet head that jets liquid along a jetting direction while moving relative to the medium in a first direction. It comprises: a nozzle plate having a nozzle surface having a plurality of nozzles for jetting liquid; and a cover having an opening that exposes a portion of the nozzle surface when viewed from the opposite direction of the jetting direction, and the cover covering at least a portion of the outer periphery of the nozzle surface. The cover has a first edge covering a portion of the outer periphery of the nozzle surface extending in a second direction orthogonal to the first direction. The first edge has a first inner edge defining the inner edge of the opening. The first inner edge has an inclined portion or a curved portion at least in the central portion in the second direction that is inclined relative to a straight line parallel to the second direction. Thus, by providing an inclined portion or a curved portion in the central portion of the first inner edge, where the medium is most easily contacted and has relatively low rigidity, the medium is less likely to get stuck between the first inner edge and the nozzle surface, suppressing paper jams and the flipping of the first edge.

[0165] The preferred form, namely the liquid injection device according to form 14, includes: a liquid injection head as described above; a carriage that holds the liquid injection head and reciprocates in the first direction; and a conveying mechanism that conveys the medium in the second direction at a position facing the nozzle. Thus, when the end of the flexural medium in the first direction contacts the liquid injection head via the reciprocating movement of the carriage in the first direction, it is possible to prevent the medium from getting stuck or entering between the cap and the nozzle surface, or for the first edge to warp.

[0166] The preferred form, namely the liquid injection device according to form 15, includes: a horizontal head composed of a liquid injection head as described above; and a conveying mechanism for conveying a medium in the first direction at a position facing the nozzle. Thus, when the end of the flexed medium in the first direction contacts the liquid injection head via the conveyed medium, it is possible to prevent the medium from getting stuck or entering between the cover and the nozzle surface, or for the first edge to warp.

Claims

1. A liquid injection head, characterized in that, have: A nozzle plate having a nozzle face having a plurality of nozzles that spray liquid in a spray direction; as well as The cover, when viewed from the opposite direction of the jet direction, has an opening that exposes a portion of the nozzle face, and the cover covers at least a portion of the outer periphery of the nozzle face. When viewed from the spray direction, the nozzle plate has a rectangular or approximately rectangular shape comprising a pair of sides extending in a first direction and a pair of sides extending in a second direction orthogonal to the first direction. The cover has a first edge that covers a portion of the outer periphery of the nozzle surface that extends in the second direction. The first edge portion has a first inner edge that defines the inner edge of the opening portion. The first inner edge has a first portion that extends not substantially parallel to the second direction. The length of the first portion in the second direction is greater than 50% of the length of the first inner edge in the second direction.

2. The liquid injection head according to claim 1, characterized in that, When viewed from the opposite direction of the jetting direction, the first inner edge has a straight second portion that is disposed at the center of the first inner edge in the second direction and extends substantially parallel to the second direction. The first part has two inclined portions that are adjacent to the two sides of the second part and are inclined relative to the second direction.

3. The liquid injection head according to claim 2, characterized in that, The first portion has two curved portions that are respectively disposed at both ends in the second direction of the first inner edge and are curved.

4. The liquid injection head according to claim 1, characterized in that, The first inner edge has a straight second portion that extends substantially parallel to the second direction. The second portion is disposed on the outermost side of the first inner edge in the first direction.

5. The liquid injection head according to claim 2, characterized in that, The tilt angle of the inclined portion relative to the second direction is 5 degrees to 10 degrees. The length of one of the inclined portions in the second direction is 25% to 40% of the length of the first inner edge in the second direction.

6. The liquid injection head according to claim 1, characterized in that, The liquid injection head moves relative to the medium in the first direction while injecting liquid along the injection direction.

7. The liquid injection head according to claim 1, characterized in that, The edge of the nozzle plate extending in the second direction contacts the abutting portion of the first edge of the cover. When viewed from the second direction, the first edge extends from the abutment toward the first inner edge of the cover in a manner away from the nozzle plate.

8. A liquid injection head, characterized in that, It is a liquid injection head that moves relative to a medium in a first direction while ejecting liquid along the injection direction, the liquid injection head comprising: A nozzle plate having a nozzle face having a plurality of nozzles for spraying liquid; as well as The cover, when viewed from the opposite direction of the jet direction, has an opening that exposes a portion of the nozzle face, and the cover covers at least a portion of the outer periphery of the nozzle face. The cover has a first edge portion that covers the outer periphery of the nozzle surface and extends in a second direction orthogonal to the first direction. The first edge portion has a first inner edge that defines the inner edge of the opening portion. The proportion of one or more straight segments that are located at the same position in the first direction and define the first inner edge and extend substantially parallel in the second direction is less than 50%, relative to the length of the first inner edge in the second direction.

9. The liquid injection head according to claim 8, characterized in that, The first inner edge has at least one of an inclined portion that is inclined relative to a straight line parallel to the second direction and a curved portion.

10. The liquid injection head according to claim 8, characterized in that, The first inner edge has a first portion that extends not substantially parallel to the second direction. The length of the first portion in the second direction is greater than 50% of the length of the first inner edge in the second direction.

11. The liquid injection head according to claim 8, characterized in that, When viewed from the opposite direction of the jetting direction, the nozzle plate is rectangular or approximately rectangular in shape, comprising a pair of sides extending in the first direction and a pair of sides extending in the second direction.

12. The liquid injection head according to claim 8, characterized in that, The first inner edge has a plurality of straight sections that are staggered in the first direction and define the first inner edge and extend substantially parallel in the second direction.

13. A liquid injection head, characterized in that, It is a liquid injection head that moves relative to a medium in a first direction while ejecting liquid along the injection direction, the liquid injection head comprising: A nozzle plate having a nozzle face having a plurality of nozzles for spraying liquid; as well as The cover, when viewed from the opposite direction of the jet direction, has an opening that exposes a portion of the nozzle surface, and the cover covers at least a portion of the outer periphery of the nozzle surface. The cover has a first edge portion that covers the outer periphery of the nozzle surface and extends in a second direction orthogonal to the first direction. The first edge portion has a first inner edge that defines the inner edge of the opening portion. The first inner edge has at least a tilted portion or a curved portion that is inclined relative to a straight line parallel to the second direction at its central portion in the second direction.

14. A liquid injection device, characterized in that, have: The liquid injection head according to any one of claims 1 to 13; A carriage that holds the liquid injection head and reciprocates in the first direction; and A conveying mechanism that conveys the medium in the second direction at a position opposite to the nozzle.

15. A liquid injection device, characterized in that, have: A linear head comprising the liquid injection head according to any one of claims 1 to 13; and A conveying mechanism that conveys the medium in the first direction at a position opposite to the nozzle.

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