JP2008055838A - Droplet discharge head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a deformation of a nozzle surface of a head unit by deforming an overhang part by a deformation part even if a reaction force of an inserted member such as an O ring for preventing a liquid leakage arises. <P>SOLUTION: A grooved part 48 is formed inside the mounting position of a mounting component 40 in a droplet discharge head, so that an overhang part 42 is deformed downward at the grooved part 48 to prevent warpage of the nozzle surface of a jet stack 20 even if the overhang part 42 of the mounting component 40 is deformed upward. Thus, a deformation of the nozzle surface is prevented by a simple configuration since only the grooved part 48 is formed as a deformation part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a droplet discharge head that discharges droplets.

  As a droplet discharge head for discharging droplets, an ink jet recording head for recording an image by discharging ink droplets onto a recording medium is known. As an ink jet recording head, an ink jet recording head disclosed in Patent Document 1 is known.

  The ink jet recording head of Patent Document 1 includes a base substrate and an ink discharge substrate that forms a pressure chamber for discharging ink. The base substrate and the ink discharge substrate are laminated with their contact surfaces bonded together.

  The central area of the contact surface of the ink discharge substrate is bonded to the contact surface of the base substrate with a high-strength adhesive having a stronger adhesive force than the elastic adhesive having elasticity even after curing, and both ends of the contact surface of the ink discharge substrate The region is bonded to the contact surface of the base substrate with an elastic adhesive.

According to this configuration, it is possible to give a necessary strength with a high-strength adhesive and reduce warpage due to expansion and contraction of the ink discharge substrate and the base substrate with an elastic adhesive.
JP 2006-21434 A

  By the way, in a droplet discharge head that discharges droplets, it is desired to prevent deformation such as warpage or deflection of the nozzle surface with a simple configuration.

  An object of the present invention is to provide a droplet discharge head that can prevent deformation of a nozzle surface with a simple configuration in consideration of the above facts.

  A droplet discharge head according to a first aspect of the present invention includes a head unit that discharges droplets, a filter unit that filters liquid sent to the head unit, and a filter unit that is provided in the filter unit and from a side wall of the filter unit. A projecting portion projecting laterally; a fixing member that fixes the projecting portion to the head unit at a predetermined position of the projecting portion; and formed on the projecting portion and disposed on the inner side of the predetermined position, And a deforming part for deforming the part.

  According to this configuration, when the overhanging portion is fixed to the head unit, an insertion member such as an O-ring for preventing liquid leakage is inserted between the filter unit and the head unit, and the reaction force of the insertion member is reduced. Even if it occurs, the overhanging portion is deformed by the deforming portion, and deformation (for example, warpage or deflection) of the nozzle surface of the head unit is prevented. Thus, since only the deformed portion is formed, the nozzle surface can be prevented from being deformed with a simple configuration.

  As a deformation part according to claim 1 of the present invention, as described in claim 2, it can be a groove part that is formed in the overhang part and has a lower rigidity than other parts of the overhang part.

  As a deformation part according to claim 1 of the present invention, as described in claim 3, it can be an opening part which is formed in the overhang part and has a lower rigidity than other parts of the overhang part.

  Since the present invention has the above configuration, it is possible to prevent deformation of the nozzle surface with a simple configuration.

  Hereinafter, an example of an embodiment according to a droplet discharge head of the present invention will be described with reference to the drawings. In this embodiment, an ink jet recording head that records an image by discharging ink droplets onto a recording medium will be described as an example of a droplet discharging head that discharges droplets.

  As shown in FIG. 1, the inkjet recording head 10 according to the present embodiment is formed in a long shape by arranging a plurality of printing units 12 and connecting them, and the image recording width capable of recording an image is equal to or larger than the width of the recording area. Ink jet recording head.

  As shown in FIG. 2, the printing unit 12 includes a filter unit 14 that removes foreign matters contained in ink as a liquid, and a head unit 16 that ejects ink droplets. As shown in FIGS. 2 and 3, the head unit 16 includes a jet stack 20 formed by laminating a plurality of flow path plates 19 and a manifold 18 bonded and fixed on the jet stack 20. Has been.

  In addition, an inlet 21 and a screw hole 17 for allowing the ink supplied from the filter unit 14 to flow in are formed in the upper portion of the manifold 18 (see FIG. 3). Further, the lower surface of the jet stack 20 is a nozzle surface on which nozzles 34 for ejecting ink droplets are formed.

  The filter unit 14 is configured to feed ink from an inlet 22 connected to an ink tank (not shown), pass the filter 24, and then supply the ink to the manifold 18. The filter unit 14 is provided with a bubble outlet 23 so that bubbles generated inside the filter unit 14 are discharged.

  The ink sent to the manifold 18 is temporarily stored in the manifold 18 and then supplied to the jet stack 20.

  The ink supplied to the jet stack 20 is sent to the pressure chamber 28 through the supply path 26, and further sent to the nozzle 34 through the communication path 32. As a result, the ink is filled into the supply path 26, the pressure chamber 28, the communication path 32, and the nozzle 34. The ink filled in the pressure chamber 28 is configured such that pressure is applied when the piezoelectric element 30 is deformed by applying a voltage, and the ink is ejected as an ink droplet from the nozzle 34.

  Next, a configuration for attaching the filter unit 14 to the head unit 16 will be described.

  As shown in FIG. 4, an attachment member 40 for attaching the filter unit 14 to the head unit 16 is provided below the filter unit 14. The attachment member 40 is provided with an overhang portion 42 that protrudes laterally from the side wall of the filter unit 14 at both ends thereof.

  A screw hole 44 is formed in each of the overhang portions 42. The filter unit 14 is attached to the head unit 16 by screwing a screw 46 as a fixing member into the screw hole 44 and the screw hole 17 formed in the manifold 18 to fix the overhanging portion 42 to the head unit 16. It is attached.

  The overhanging portion 42 is configured to be fixed to the head unit 16 at a predetermined position where the screw hole 44 into which the screw 46 is screwed, and the position where the screw hole 44 is formed is a fixed position. .

  Inside the fixed position, as shown in FIGS. 5A and 5B, a groove portion 48 is formed as a deformed portion on the lower surface side of the mounting member 40. The groove 48 is formed in a rectangular cross section. Due to the groove portion 48, the rigidity of the attachment member 40 (the overhang portion 42) becomes lower than other portions where the groove portion 48 is not formed. That is, the groove portion 48 constitutes a low-rigidity portion of the overhanging portion 42, and the attachment member 40 (the overhanging portion 42) is more likely to be deformed than other portions in this portion.

  In the present embodiment, the groove 48 is formed below the side wall 14 </ b> A of the filter unit 14. The position where the groove 48 is formed may be between the screw hole 44 and the position below the side wall 14A.

  An inflow port 52 for allowing ink to flow from the filter unit 14 is formed at the center of the mounting member 40 (see FIG. 5B).

  Next, the operation of the above embodiment will be described.

  Even if the groove portion 48 according to the present embodiment is not formed, the filter unit 14 can be attached to the head unit 16 as shown in FIG. However, as shown in FIG. 7A, when the overhanging portion 42 of the mounting member 40 is deformed upward, when the screw 46 is tightened, the manifold 18 is pulled upward, and as a result, the nozzle of the jet stack 20 The surface will also warp.

  7B, when an insertion member 50 such as an O-ring or an adhesive for preventing ink leakage is inserted between the filter unit 14 and the head unit 16, the insertion member 50 is inserted. Due to the reaction force, the nozzle surface of the jet stack 20 also warps. Further, even when the overhanging portion 42 of the filter unit 14 is deformed downward or the mounting surface of the manifold 18 is similarly deformed, warpage and deflection are generated on the nozzle surface of the jet stack 20.

  When the nozzle surface of the jet stack 20 is warped, ink discharge due to deterioration of discharge characteristics (for example, landing position deviation) due to axial misalignment of the nozzle holes and peeling of the adhesive bonding the manifold and the flow path plate occurs. there's a possibility that.

  On the other hand, in this embodiment, the groove part 48 is formed inside the fixed position of the overhang part 42 of the attachment member 40. For this reason, as shown in FIG. 8A, even if the overhanging portion 42 of the mounting member 40 is deformed upward, the overhanging portion 42 is deformed downward in the groove 48 and the nozzle of the jet stack 20 The face does not warp.

  Even if an insertion member 50 such as an O-ring or an adhesive is inserted between the filter unit 14 and the head unit 16, even if a reaction force of the insertion member acts as shown in FIG. The overhanging portion 42 is deformed downward in the groove portion 48 and the nozzle surface of the jet stack 20 does not warp.

  For this reason, there is no possibility that the discharge characteristic (for example, landing position deviation) is deteriorated due to the axial deviation of the nozzle holes and the adhesive bonding the flow path plate 19 and the manifold 18 constituting the jet stack 20 is peeled off.

  Thus, since only the groove portion 48 as the deforming portion is formed, the nozzle surface can be prevented from being deformed with a simple configuration.

  Moreover, according to the structure of this embodiment, the curvature of a nozzle surface can be prevented by reducing the rigidity of the attachment member 40, without making the thickness of a screw fastening part thin.

  Further, regardless of the accuracy (for example, flatness) of the mounting surfaces of the filter unit 14 and the manifold 18, the nozzle surface is not warped or bent even when the filter unit 14 is mounted.

  For this reason, the component accuracy specifications of the filter unit 14 and the manifold 18 can be relaxed, leading to cost reduction.

  In the above embodiment, the groove portion as the deformation portion is formed in a rectangular cross section, but the shape of the groove portion may be a triangular cross section as shown in FIG. As shown in FIG. 9C, the edge of the groove part may be formed in a U-shaped cross section, and the bottom surface (back surface) of the groove part may be rounded. As described above, the shape of the groove is arbitrarily set as long as the rigidity is lower than that of other portions where the groove is not formed.

  Moreover, in the said embodiment, although the groove part as a deformation | transformation part was formed in the lower surface side of the attachment member 40, you may form in the upper surface side of the attachment member 40, as shown to FIG. 9 (A).

  Further, as shown in FIG. 10, the groove portion may be formed on both the upper surface side and the lower surface side of the attachment member 40. Further, as shown in FIG. 11, the groove portion may be formed on the side surface side of the attachment member 40. Thus, the position where the groove portion is formed can be formed at any position on the upper surface, the lower surface, and the side surface of the attachment member 40.

  Also, as shown in FIG. 12, an opening 54 may be formed as the deformed portion. The shape of the opening 54 may be a round shape or a rectangular shape, and the shape of the opening 54 is arbitrarily set as long as the rigidity is lower than other portions where the opening 54 is not formed. The same effect can be obtained even if the number of the openings 54 is plural.

  Further, the attachment method for attaching the filter unit 14 to the head unit 16 is not limited to screw fastening, and may be welding, snap fitting, or the like.

  The present invention is not limited to this embodiment, and various modifications, changes, and improvements can be made.

FIG. 1 is a perspective view showing a configuration of an ink jet recording head according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing the configuration of the printing unit according to the present embodiment. FIG. 3 is an exploded perspective view showing the configuration of the head unit according to the present embodiment. FIG. 4 is a perspective view showing the configuration of the printing unit according to the present embodiment. FIG. 5A is a side view showing the configuration of the joining member according to this embodiment, and FIG. 5B is a bottom view showing the configuration of the joining member according to this embodiment. FIG. 6 is a side view showing a configuration in which the groove portion according to the present embodiment is not formed. FIG. 7 is a side view showing a state in which the filter unit is attached to the head unit in a configuration in which the groove portion according to the present embodiment is not formed, and FIG. 7A shows a case where the overhanging portion is deformed upward. (B) shows the state which inserted the insertion member between the filter unit and the head unit. FIG. 8 is a side view illustrating a state in which the filter unit is attached to the head unit in the configuration of the joining member according to the present embodiment. FIG. 8A illustrates a case where the overhang portion is deformed upward. B) shows a state in which an insertion member is inserted between the filter unit and the head unit. FIG. 9 is a view showing a modified example of the groove part according to the present embodiment, (A) shows an example in which the groove part is formed on the upper side of the joining member, and (B) shows a triangular shape of the groove part. An example is shown and (C) shows the example which made the edge of the groove part U-shaped. FIG. 10 is a side view showing a modification in which the groove portion according to the present embodiment is formed on both the upper side and the lower side of the joining member. FIG. 11A is a side view showing a modification in which the groove portion according to the present embodiment is formed on the side surface of the joining member, and FIG. 11B is a side view of the groove portion according to the present embodiment formed on the side surface of the joining member. It is a bottom view showing a modified example. FIG. 12A is a side view showing a modification in which an opening is formed in the joining member according to the present embodiment, and FIG. 12B is a modification in which an opening is formed in the joining member according to the embodiment. It is a bottom view which shows an example.

Explanation of symbols

10 Inkjet recording head (droplet ejection head)
14 Filter unit 16 Head unit 42 Overhang portion 46 Screw (attachment member)
48 Groove (deformed part)
54 Opening (deformed part)

Claims (3)

A head unit for discharging droplets;
A filter unit for filtering the liquid sent to the head unit;
An overhang provided on the filter unit and projecting laterally from the side wall of the filter unit;
A fixing member for fixing the overhang portion to the head unit at a predetermined position of the overhang portion;
A deforming portion that is formed on the overhanging portion, is disposed on the inner side of the predetermined position, and deforms the overhanging portion;
A liquid droplet ejection head comprising:   2. The droplet discharge head according to claim 1, wherein the deformable portion is a groove portion that is formed in the overhang portion and has lower rigidity than other portions of the overhang portion.   2. The droplet discharge head according to claim 1, wherein the deformable portion is an opening that is formed in the overhang portion and has lower rigidity than other portions of the overhang portion.

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