JP3513992B2 - Multilayer inkjet recording head - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated ink jet recording head in which an actuator unit made of ceramics and a flow path substrate made of metal are joined. About. 2. Description of the Related Art For example, as shown in Japanese Patent Application Laid-Open No. 6-40035, a piezoelectric vibration plate is adhered to a part of an elastic plate constituting a pressure generating chamber, An ink jet recording head that generates ink droplets by changing the volume of a pressure chamber by flexural displacement can displace a large area of the pressure generating chamber, and thus can stably generate ink droplets. It has. [0003] Such a recording head usually includes actuator units A, B, and C in which a pressure generating chamber, a vibration plate, and a piezoelectric vibration plate are manufactured by sintering ceramics as shown in FIG. It is roughly divided into a single flow path constituting unit D made of a metal plate formed corresponding to the nozzle opening row, and a plurality of actuator units A, B,
C is fixed to the channel unit D with an adhesive. In the case where a plurality of actuator units are provided as described above, the distance between the nozzle opening rows is made as small as possible so that the dot formation position due to the inclination or the like is reduced. In order to reduce the error, it is necessary to reduce the distances L, L between the actuator units, and the area that can be allocated to the common ink chamber becomes small, so that a sufficient amount of ink is supplied to the pressure generation chamber. When the thickness of the spacer that constitutes the flow path unit is increased in order to increase the volume of the common ink chamber, the work of drilling a minute communication hole that connects the nozzle opening and the pressure generation chamber becomes difficult. There is a problem that it becomes difficult. The present invention has been made in view of such a problem, and an object of the present invention is to increase the area of a common ink chamber without increasing the area of a reservoir or the thickness of a spacer. Another object of the present invention is to provide a laminated ink jet recording head capable of enlarging a sectional area and smoothly supplying ink required for printing to a pressure generating chamber. According to the present invention, there is provided a first lid member made of ceramic having a piezoelectric vibrating plate on its surface to form a vibrating member. An actuator unit in which one surface is sealed by the lid member and a spacer made of ceramic forming a pressure generation chamber is integrally joined by firing, and the actuator unit is fixed, and both ends of the pressure generation chamber are fixed. a communication hole and an ink supply port communicating with the, or external
An ink supply port forming substrate made of metal having an ink introduction port for receiving ink supply from the same, a common ink chamber communicating with the pressure generation chamber via the ink supply port, and communicating with the pressure generation chamber A common ink chamber forming substrate having a communication hole, and a nozzle plate having a nozzle opening for sealing the other surface of the common ink chamber forming substrate and connecting to the pressure generating chamber through each of the communication holes. And the ink supply port of the ink supply port forming substrate is connected to the pressure generating chamber.
It is formed so as to be located on one end side, is opposed to the common ink chamber , and is located inside the ink supply port.
So that a concave portion is formed on the surface facing the common ink chamber,
So that the tip side away from the ink inlet is tapered
It is formed and formed . The inside of the ink supply port forming substrate is located inside the ink supply port.
Recesses are formed on the side of the side facing the common ink chamber
Therefore, the volume and cross-sectional area of the common ink chamber can be increased without increasing the thickness of the spacer , and ink can be smoothly supplied to the pressure generating chamber. Also, ahead
Since the end side is tapered, air bubbles are common.
It can be prevented from remaining in the ink. An embodiment of the present invention will now be described with reference to the drawings. FIG. 1 is an assembled perspective view showing the entire recording head of the present invention without a heat welding film, and FIG. 2 is a sectional view showing a structure near a pressure generating chamber of one actuator unit. , Symbol 2 in the figure
Is a first lid plate made of a thin plate of zirconia having a thickness of about 10 μm, on the surface of which a drive electrode 5 is formed so as to face a pressure generating chamber 4 described later, and a piezoelectric electrode made of PZT or the like is formed thereon. The diaphragm 3 is fixed. Pressure generating chamber 4
Receives the flexural vibration of the piezoelectric vibration plate 3, contracts and expands, ejects ink droplets from the nozzle openings 28, and sucks ink from the common ink chamber 23 through the ink supply port 20. Reference numeral 7 denotes a spacer, which has a thickness suitable for forming the pressure generating chamber 4, for example, zirconia (Z
The pressure generating chamber 4 is formed by forming a through hole in a ceramic plate such as rO2) and sealing both surfaces with a second lid 8 and a first lid 2 described later. . Reference numeral 8 denotes a second lid, which is a communication hole 9 for connecting an ink supply port 20 and a pressure generating chamber 4 to a ceramic plate made of zirconia or the like, which will be described later. A communication hole 10 connecting the end is formed, and is fixed to the other surface of the spacer 7. The members 2, 7, and 8 are formed into a predetermined shape by forming a clay-like ceramic material, laminated, and fired to form the actuator unit 1 without using an adhesive. . Reference numeral 21 denotes a substrate for forming an ink supply port, which serves as a fixed substrate for the actuator unit 1 and has the greatest rigidity among members in the recording head so that a connecting member for connecting to the ink tank can be provided. It is a required member. For this reason, metals and ceramics such as non-rust steel having ink resistance are selected as the materials. The surface of the ink supply port forming substrate 21 facing the common ink chamber 23 is provided with a common ink chamber so as to be located inside the common ink chamber 3 as shown in FIGS. A concave portion 21a having an open side is formed. By forming the recess 21a in the region inside the common ink chamber 23 and the tip thereof is tapered similarly to the common ink chamber 23, it is possible to prevent bubbles from remaining in the recess 21a, Further, interference can be prevented. In particular, in order to promote the elimination of air bubbles, the concave portion 21a is provided with FIG.
The corners are chamfered as shown in FIG. When a metal is used as the ink supply port forming substrate 21, such a concave portion 21a has a common ink chamber 2 of the ink supply port forming substrate 21 as shown in FIG.
The recess 40 is formed on the surface opposite to the surface 3 by pressing or the like.
(A)), the protrusion 41 on the other surface is polished (FIG. 5).
(B)) Finish to a flat surface (FIG. 5 (c)). As another method, an etching protective film 43 having a window 42 is formed on the surface of the ink supply port forming substrate 21 facing the common ink chamber (FIG. 6A), and only one surface is formed. Is formed after etching to form a concave portion 44 (FIG. 6).
(B)), the etching protection film 43 is removed (FIG. 6)
Methods such as (c)) can be adopted. Another method is to prepare a plate material obtained by laminating and joining two non-rusting steels via a plastic film, and select a portion corresponding to the recess of the non-rusting steel on one surface using the plastic film as an etching stopper. In addition, there is a processing method such as forming a thick portion by performing electroforming while masking a portion corresponding to a concave portion on the surface of the substrate. Returning to FIG. 2 again, the ink supply port forming substrate 2
1, an ink supply port 20 for connecting a common ink chamber 23 and the pressure generation chamber 4 described later is provided at one end of the pressure generation chamber 4 near the concave portion 21a, and the other end of the pressure generation chamber 4 is provided. Is provided with a communication hole 24 connected to the nozzle opening 28. Further, ink introduction ports 22, 22, 22 into which ink flows from an ink tank (not shown) are formed at positions outside the fixing area of the actuator unit 1. Reference numeral 25 denotes a common ink chamber forming substrate, which has a thickness suitable for forming the common ink chamber 23, for example, 150.
A through hole corresponding to the shape of the common ink chamber 23 and a communication hole 26 connecting the nozzle opening 28 of the nozzle plate 27 are formed in a corrosion-resistant plate material such as stainless steel having a thickness of μm. I have. The ink supply port forming substrate 21, the common ink chamber forming substrate 25, and the nozzle plate 27 are respectively provided between the heat-sealing film and the adhesive layers 32, 3 of an adhesive.
3 and fixed to the flow path unit 30. On the surface of the ink supply port forming substrate 21 of the channel unit 30, a heat-sealing film or an adhesive layer 3 of an adhesive is applied.
1, the actuator unit 1, 1, 1 is fixed to form a recording head. In the drawing, reference numeral 14 denotes a common electrode formed on the surface of the piezoelectric vibrating plate 3, and 15 denotes a flexible cable connected to an external device. According to this embodiment, the common ink chamber 23
The thickness of the ink supply port forming substrate 21 formed on the surface opposite to the concave portion 21a is increased by an amount corresponding to the concave portion 21a.
5 without increasing the thickness of the common ink chamber 23,
In addition, the volume required can be increased, and the ink required for forming the ink droplets can be smoothly supplied to each pressure generating chamber 4.
Further, since there is no need to increase the thickness of the spacer 25, the communication hole 26 can be easily formed. In the above-described embodiment, an example was described in which the common ink chamber 23 was formed so as to be biased toward one side of the pressure generating chamber 4. However, as shown in FIG. For the recording head enlarged to the other area of the chamber 4,
Even if the concave portion 21a formed in the ink supply port forming substrate 21 is formed in a region facing the pressure generating chamber 4, the thickness of the common ink chamber 23 increases by the amount of the concave portion 21a of the ink supply port forming substrate 21. The cross-sectional area and volume of the common ink chamber 23 can be increased without increasing the thickness of the spacer 25, and the ink required for forming the ink droplets can be smoothly supplied to each pressure generating chamber 4. [0024]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an assembled perspective view showing one embodiment of an ink jet recording head of the present invention. FIG. 2 is a cross-sectional view showing one embodiment of the ink jet recording head of the present invention with a structure near a pressure generating chamber of one actuator unit. FIG. 3 is a diagram illustrating a positional relationship between a concave portion and a common ink chamber. FIG. 4 is a diagram showing a cross-sectional structure of the concave portion along line AA in FIG. 3; FIGS. 5A to 5C are diagrams illustrating steps for forming a concave portion in an ink supply port forming substrate, respectively. FIGS. 6A to 6C are diagrams showing steps for forming a concave portion in an ink supply port forming substrate, respectively. FIG. 7 is a sectional view showing another embodiment of the present invention with a structure near a pressure generating chamber of one actuator unit. FIG. 8 is a sectional view showing another embodiment of the present invention with a structure near a pressure generating chamber of one actuator unit. FIG. 9 is a perspective view showing an example of an ink jet recording head in which a plurality of actuator units are provided in a channel unit. [Description of Signs] 1 Actuator unit 2 First lid 3 Piezoelectric vibrating plate 4 Pressure generating chamber 7 Spacer 8 Second lid 9, 10 Communication hole 20 Ink supply port 21 Ink supply port forming substrate 21a Concave section 22 Ink introduction Orifice 23 Common ink chamber 27 Nozzle plate 28 Nozzle opening 30 Channel unit

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Fujio Akabane 3-5-5 Yamato, Suwa-shi, Nagano Pref. Seiko Epson Corporation (56) References JP-A-6-234218 (JP, A) JP-A-Hei 4-347650 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B41J 2/045 B41J 2/055

Claims (1)

(57) [Claim 1] A first lid member made of ceramic and having a piezoelectric vibration plate on a surface to form a vibration member, and one surface is sealed by the lid member. An actuator unit in which a ceramic spacer that forms the pressure generating chamber is integrally joined by firing, an actuator unit to which the actuator unit is fixed, and a communication hole and an ink supply port that communicate at both ends of the pressure generating chamber; An ink supply port forming substrate made of metal having an ink introduction port for receiving ink supply from the ink supply port; a common ink chamber communicating with the pressure generation chamber via the ink supply port; and a communication with the pressure generation chamber A common ink chamber forming substrate having a communication hole,
The other surface of the common ink chamber forming substrate is sealed and bonded to a flow path unit formed by joining a nozzle plate having a nozzle opening connected to the pressure generating chamber through the communication holes. The ink supply port of the ink supply port forming substrate is formed so as to be located at one end side of the pressure generating chamber, is opposed to the common ink chamber, and is located inside the ink supply port. A multilayer ink jet recording head, wherein a concave portion is formed on a surface facing the common ink chamber so that a tip end side away from the ink introduction port is tapered.