JPS63280648A - Ink jet head - Google Patents

Abstract

PURPOSE:To reduce the number of component parts and prevent clogging with air bubbles from occurring, by forming a joint part in a body with a substrate provided with a groove part for constituting a passage, or with a second substrate to be laminated with the above substrate to constitute the passage. CONSTITUTION:An ink jet head comprises a substrate 1, which is provided with groove parts for constituting passages, namely, a common supplying passage 10, discrete supplying passages 9, pressurizing chambers 8 and nozzles 7, a second substrate 2 to be laminated with the substrate 1 to constitute closed passages, piezoelectric elements 4 disposed correspondingly to the pressurizing chambers 8, respectively, and a metallic plate 3 serving as a common electrode plate. The substrate 1 is provided integrally with a joint part 5, which is provided in the shape of a hollow cylinder where it is to be connected to a tube or the like. Thus, the number of component parts such as separate joint parts, seal packings and screws can be reduced, and the interior of the joint part is formed in a smooth stepless form, so that defective printing can be prevented from occurring due to catching of an air bubble in the joint part, growth of the bubble with a temperature variation or the like and entering of the bubble into the pressurizing chamber, or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet recording device, and more particularly to the structure of an inkjet head.

[Conventional technology]

As shown in FIG. 9, in the conventional inkjet head, ink guided by an ink cartridge lip 12 and a retube 11 is supplied through a common supply path 1o into a substrate 1 in which a groove serving as a flow path is formed. A separate joint portion 5 was fixed between the tube 11 and the substrate 1 with a seal packing 13 sandwiched therebetween by screws 6 or the like. Further, in order to supply a plurality of types of ink, a substrate is required for each ink, and a seal packing and a joint portion are required for each substrate.

[Problem that the invention seeks to solve]

However, in the conventional technology, the joint part is separate,
In addition, parts such as seal packings and screws are required for fixing, which increases costs and takes time to assemble. Furthermore, a step always occurs at the joint between the joint and the flow path inlet of the substrate, and air bubbles that have entered due to insertion and removal of the cartridge are caught in this step, grow due to temperature changes, etc., and enter the pressurizing chamber. This caused printing defects. Furthermore, since the seal is formed through a gasket made of rubber or the like, there are problems with its durability and sealing performance, and in particular, depending on the ink used, precipitates may form and clog the nozzle. Furthermore, when supplying multiple types of ink, separate substrates are required for each type, resulting in an increase in the size of the head.

The present invention is intended to solve these problems.The purpose of the present invention is to reduce the number of parts, lower the cost of the head, and prevent problems such as air bubbles from getting caught, ink leakage, and nozzle clogging. The objective is to supply an inkjet head with a structure that prevents this. Another object of the present invention is to provide an inkjet head having a structure capable of supplying a plurality of types of ink to one substrate.

[Means for solving the problem]

In the inkjet head of the present invention, as a means for achieving this object, the joint part with the tube etc. is a substrate in which a groove part serving as a flow path is formed, or a second substrate that is laminated on this to form a closed flow path. If necessary, a plurality of these joints are provided on the board or the second board, and the flow path inside each joint communicates only with an arbitrary flow path. It is characterized by the presence of

〔Example〕

FIG. 1 and FIG. 2 are diagrams showing one embodiment of the present invention,
It consists of a substrate 1 in which a groove serving as a flow path is formed, a second substrate 2 and a piezoelectric element 4 that are laminated thereon to form a closed flow path, and a metal scrap plate 3 as a common electrode plate. This metal scrap plate 3 may be made of conductive rubber, a conductive film, etc. (or may not be used depending on the case).

A joint portion 5 is integrally provided on the substrate 1 when the substrate is formed. The shape of this joint part is preferably a hollow cylinder when it is connected to a tube or the like, but the shape is not particularly limited as long as it is suitable for the shape of the parts to be connected. Further, the joint portion may be located anywhere as long as it is on the outer periphery.

3 and 4 show a second embodiment of the present invention, in which a second substrate 2 is laminated on a substrate 1 in which a groove serving as a flow path is formed to form a closed flow path. A joint portion is formed integrally.

FIG. 5 shows another embodiment of the present invention, in which grooves serving as flow paths are formed on both sides of a substrate 1, and a joint portion is formed integrally with this substrate 1. This flow path within the joint portion is internally divided into two parts, and communicates with the flow path portions on each surface. This makes it possible to supply the same ink to the pressure chambers on both sides, and only one joint is required.

FIG. 6 shows another embodiment of the present invention, in which a second substrate 2 is laminated on each surface to form a closed channel in a substrate 1 in which grooves serving as flow channels are formed on both sides. -a
, 2-b are each provided with a joint portion. This allows the same or two types of ink to be supplied to the channels on each side.゛Figure 7 is another embodiment of the present invention,
A plurality of joint parts are formed on the outer peripheral part of the substrate, and each joint part communicates only with an arbitrary flow path. If there are flow channels on both sides, it is possible to create a structure in which the flow channels connect to channels on any surface inside.

FIG. 8 shows another embodiment of the present invention, in which a plurality of joint portions 5 are formed on one side of the second substrate to be laminated, and are in communication with the respective flow channels. If this structure is provided on both sides of the 21T2 substrate, more types of ink can be supplied. Note that the number of nozzles is not particularly defined in FIGS. 1 to 8.

〔Effect of the invention〕

As described above, according to the present invention, the joint portion is integrated with a substrate in which a groove serving as a flow path is formed, or a second substrate that is laminated on the substrate to form a closed flow path. Because of this structure, the need for separate joints, seal backs, screws, etc. can be reduced, reducing costs and reducing the time required for assembly. Furthermore, since the inside of the joint is formed smoothly and without any steps, air bubbles can get caught in the steps.
It will not grow due to temperature changes and eventually invade the pressure chamber, causing printing defects. Furthermore, since a sealing pad made of rubber or the like is not required, it is durable and the nozzle does not become clogged with deposits from the rubber.

Furthermore, as shown in FIG. 5 of the embodiment, the same ink can be supplied to both surfaces from one joint port, and the structure can be simplified. Further, in the embodiments shown in FIGS. 6 to 8, different types of ink can be supplied only to any flow path on any surface. This makes it possible to print with multiple types of ink with a single head, making it possible to configure a multi-color head or the like. In all of these embodiments, when the substrate is molded by injection molding or the like, the joint portion can be configured in any shape, so that it can be joined to an ink supply member of any shape.

[Brief explanation of the drawing]

1.3 and 7.8 are perspective views of the flow path portion of an inkjet head showing an embodiment of the present invention. 2 is a right side view of the head shown in FIG. 1, and FIG. 4 is a right side view of the head shown in FIG. 3. FIG. 5.6 is a right side view of an inkjet head showing an embodiment of the present invention. FIG. 9 shows a conventional embodiment, and FIG. 10 is a sectional view of the head shown in FIG. DESCRIPTION OF SYMBOLS 1... Substrate 8... Pressure chamber 2... Second board 9... Supply path 3... Metal plate 10... Common supply path 4... Piezoelectric element 11... Tube 5 ...Joint part 12...
・Ink cartridge 6...Fixing screw 13...Seal packing 7...Nozzle and above Applicant Seiko Epson Co., Ltd. Agent Tsutomu Mogami and 1 other person, patent attorney Figure 5
Figure 6

Claims (3)

[Claims] (1) A substrate on which liquid ink is ejected from a nozzle to record on a recording medium, and grooves such as a nozzle, a pressurizing chamber, and a supply path are formed on the surface; a second substrate laminated on the substrate; 2
In the inkjet head, the piezoelectric element is bonded to or fixed to one of the two substrates via a conductive substance, or is directly bonded to or fixed to one of the two substrates by pressure. An inkjet head characterized in that a joint portion for connecting an ink supply member is integrally formed on one or both of the substrates. (2) An inkjet head characterized in that the flow path within the joint portion according to claim 1 is divided into a plurality of channels inside the substrate. (3) A plurality of the joint parts according to claim 1 are provided on the outer periphery of the substrate, or on one or both sides of the second board, or on the outer periphery of the board and one or both sides of the second board. An inkjet head characterized in that a plurality of joint parts are formed in the inkjet head, each of which independently communicates only with an arbitrary flow path.