JPH04146152A - Ink jet recording head - Google Patents

Abstract

PURPOSE:To realize cost reduction by a constitution wherein an ink passage is formed in a channel space by means of a channel board and a supply pipe or a head case. CONSTITUTION:A plurality of ink jet nozzles 2 penetrate in the widthwise direction and a channel board 1 having engraved channels communicated with respective ink jet nozzles 2 is jointed through adhesive or solvent to a vibration board 6 thus forming a channel space 3, a common ink chamber 4, and an ink chamber 5 to be connected with a supply pipe. The vibration board 6 is provided with a hole to be communicated with an ink passage at a part located above the ink chamber 5 for supply pipe and a supply pipe 7 formed by the inner diameter of the hole in the ink passage is secured through adhesive or welding to the vibration board 6 while surrounding the hole. In such structure, a series of ink passage is formed through the supply pipe 7 in the head, the ink chamber 5, the ink chamber 4, the channel space 3 and the nozzle 2. According to the constitution, number of parts and manufacturing manpower are reduced and the number of joints in the ink supply passage is also reduced resulting in a highly reliable low cost recording head.

Description

DETAILED DESCRIPTION OF THE INVENTION C. Industrial Application Field The present invention relates to an inkjet recording head that forms an image on a recording medium by ejecting ink droplets.

[Prior Art] Conventionally, in the ink supply path from an ink storage system such as an ink cartridge or an ink pack to a flow path board, a plurality of channels are used to connect the ink path outside the head to the flow path board inside the head. It was formed by connecting the parts.

[Problems to be Solved by the Invention] However, the conventional method requires a plurality of parts and a manufacturing process such as connection between these parts in order to supply ink to the flow path space. - In addition, a plurality of parts are interposed in the ink path, and the number of connection points in the ink path increases, increasing the number of points where ink leaks can occur and reduce reliability. This leak causes a short circuit in the electrical wiring system inside the head and significantly reduces the pressure propagation efficiency inside the flow path space, leading to a decrease in the overall reliability of the head.

The present invention is intended to solve these problems, and its purpose is to pursue cost benefits by reducing the number of parts and manufacturing man-hours, and to improve reliability by reducing the number of connections in the ink supply path. Our objective is to provide a highly reliable, low-cost inkjet recording head.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the inkjet recording head of the present invention has an inkjet recording head that supplies ink to a flow path space from a connection part with an ink path outside the head to an inside of the head. The inner diameter of the ink flow path substrate is formed by a supply pipe forming an ink path or by the helad case.

[Example] An example of the present invention will be explained with reference to the drawings. FIG. 1 is a front view of a channel substrate 1 according to the present invention.

A plurality of ink jet nozzles 2 penetrate in the thickness direction,
The flow path substrate 1 carved with a flow path shape that communicates with each of the ink jet nozzles 2 and the diaphragm 6 are bonded together with adhesive or a solvent, and a flow path space 3, a common ink chamber 4, and an ink chamber 5 for connecting a supply pipe are formed. It is formed. A hole is opened in the portion of the diaphragm 6 located above the ink chamber 5 for the supply pipe for ink passage communication, and a supply pipe 7 whose inner diameter forms an ink passage surrounds the hole.
However, it is fixed to the diaphragm 6 by adhesion or welding. In this structure, a series of ink paths are formed inside the head, starting from the supply pipe 7, extending to the ink chamber 5 for connecting the supply vibrator, the common ink chamber 4, the flow path space 3, and the ink jet nozzle 2.

Further, FIG. 2 shows an embodiment of the present invention using the supply pipe 7, and is a sectional view of the flow path substrate 1 in FIG. 1 assembled as a head. A filter 8 is fixed to the inner diameter of the supply pipe 7 perpendicularly to the ink path.
This filter 8 captures dust, foreign matter, etc. that may cause clogging of the ink jet nozzle 2 flowing from the upstream ink storage system, and prevents it from entering the flow path space 3 and the like. Further, the tip of the supply pipe 7 is molded or processed into a shape for connection to an ink tube 9 that conveys ink from the ink storage system, and the ink tube 9 is connected to the tip. A piezoelectric element 10 is fixed onto the diaphragm 6 via the diaphragm 6 above the flow path space 3 .

This mechanical deformation of the piezoelectric element 10 causes a pressure change in the flow path space 3 filled with ink, causing the ink jet nozzle 2
Eject more ink droplets. Moreover, except for the surface where the ink jet nozzles 2 are arranged, an FPCI is used for electrically wiring the flow path substrate 1, the vibration plate 6, the piezoelectric element 10, and the piezoelectric element 10.
A herad case 12 is connected to the channel substrate 1 so as to hermetically seal the channel I. Note that the arrow direction in the figure indicates the direction in which ink droplets are ejected. In this structure, the diaphragm 6 inside the head is connected to the ink path outside the head.
The supply pipe 7 is the only part that constitutes the ink path, and the connections as the ink path are at two locations: between the ink tube 9 and the supply pipe 7, and between the supply pipe 7 and the diaphragm 6. Therefore, not only the number of parts can be reduced, but also the reliability against leakage can be greatly improved.

Further, in a type in which an ink storage system such as an ink cartridge is directly attached to an inkjet recording head, an ink supply needle 9a is press-fitted and fixed at the tip of a supply pipe 7, as shown in FIG. In the following description of the embodiments, both the ink tube connection type and the ink supply needle type will be included, and the explanation will be based on the ink tube connection type.

Next, the head case 1 is used as the ink path inside the head.
An embodiment of the present invention using No. 2 will be explained with reference to the drawings. First, in FIG. 4, the head case 12 is
As shown in the figure, it has a shape that forms an ink path inside, and that shape is extended to the diaphragm 6 side, and is bonded to the diaphragm 6.
Or it's welded. The portion of the diaphragm 6 that corresponds to the ink path has a hole, as a matter of course, and the ink chamber 5 for connecting the supply vibrator serves as the ink path.
is connected to. Note that the filter 8 is fixed inside the ink path of the head case 12, as shown in the figure. Further, an extension of the head case 12 on the side opposite to the diaphragm 6, which is shaped to form an ink path, has a shape to which an ink tube 9 can be connected, or a shape to which an ink supply needle 9a can be press-fitted.

As the next example, in FIG.
A gasket 13a is sandwiched between the member forming the ink path No. 2 and the diaphragm 6 to ensure the sealing of the ink path. Note that the clamping force is between the channel substrate 1 and the helad case 12.
This is achieved by connecting at the outer periphery of the The rest of the concept is the same as the embodiment shown in FIG. In this structure, the connection reference between the flow path substrate 1 and the helad case 12 is only the outer peripheral surface of the flow path substrate 1 and the helad case 12, as shown in the figure, and the vibration of the members forming the ink path of the head case 12 The surface level difference accuracy with the tip surface on the plate 6 side can be canceled by the amount of deformation of the packing 13a.

Next, an embodiment in which the members forming the ink path of the head case 12 are directly connected to the flow path substrate 1 without using the diaphragm 6 will be described using FIG. 6(a) and FIG. 6(b). . FIG. 6(a) is an enlarged view of the channel substrate 1 in the vicinity of the connecting portion between the member forming the ink channel of the head case 12 and the channel substrate 1 in this embodiment. Further, FIG. 6(b) is an enlarged view of the feeding cross section when this channel substrate 1 is assembled as a head. As shown in these figures, in the flow path substrate 1, the ink chamber 5a for connecting the head case is provided as a through hole in the thickness direction, and a groove for forming an ink path is provided on the nozzle surface side to communicate with the ink chamber 5a. By attaching the nozzle side plate 14 so as to cover the groove, a nozzle side ink path 16 is formed. In order to return the ink path to the surface where the flow path space 3 is formed, the ink path on the nozzle surface side], 6 and the common ink chamber 4 on the diaphragm 6 side are communicated through the ink path through hole 15.

In this structure, ink flowing from the ink tube 9 flows through the ink path forming member of the head case 12, the ink chamber 5a for connecting the head case, and the ink path 16 on the nozzle surface side.
, ink path through hole 15, common ink chamber 4, flow path space 3
, flows through a series of ink paths of the ink jet nozzle 2. Note that the filter 8 is fixed inside the ink path of the head case 12.

Further, another embodiment in which the members forming the ink path of the head case 12 are directly connected to the flow path substrate 1 without using the diaphragm 6 will be described using FIG. 7(a) and FIG. 7(b). do. FIG. 7(a) is an enlarged view of the channel substrate 1 in the vicinity of the connecting portion between the member forming the ink channel of the head case 12 and the channel substrate 1 in this embodiment. Also, Figure 7 (
b) is an enlarged longitudinal cross-sectional view of the flow path substrate 1 assembled as a head. As shown in FIGS. 7(a) and 7(b), in the flow path substrate 1, the ink chamber 5a for connecting the head case is provided as a through hole in the thickness direction, and is commonly provided on the nozzle surface side so as to communicate with the ink chamber 5a. There is an engraving forming an ink chamber 4, and a common ink chamber 4 is formed on the nozzle surface side by attaching the nozzle side plate 14 so as to cover the engraving. Ink path through holes 15 are opened from the common ink chamber 4 to each of the flow path spaces 3. In this structure, ink flowing from the ink tube 9 flows through the ink path forming member of the head case 12, the head case connection ink chamber 5a, the common ink chamber 4 on the nozzle surface side, the ink path through hole 15, the flow path space 3, The ink flows through a series of ink paths of the ink jet nozzle 2.

Note that the filter 8 is fixed inside the ink path of the helad case 12.

Next, as another example in which the members forming the ink path of the head case 12 are directly connected to the flow path substrate 1 without using the diaphragm 6, FIGS. 8(a) and 8(b) are shown. Use and explain. FIG. 8(a) is an enlarged view of the channel substrate 1 in the vicinity of the connecting portion between the member forming the ink channel of the head case 12 and the channel substrate 1 in this embodiment. Also, the 8th
Figure (b) is an enlarged longitudinal cross-sectional view of the flow path substrate 1 assembled as a head. As shown in these two figures,
In the channel substrate 1, from the end surface of the channel substrate 1 to the center of the substrate -
An ink passage lateral hole 16a is opened in both directions, and an ink chamber 5a for connecting the head case communicates with the ink passage lateral hole 16a from the surface of the diaphragm 6. Further, from the common ink chamber 4 (the surface on the diaphragm 6 side), an ink path hole 15a (thickness direction) communicates with an extension of the ink path lateral hole 16a. Incidentally, the opening of the ink path side hole 16a at the end surface of the flow path substrate 1 is closed by connecting the head case 12, as shown in the figure. It is also effective to use a sealing material or a sealing member to cover the area. In this structure, ink flowing from the ink tube 9 flows through the ink path forming member of the head case 12, the head case connection ink chamber 5a, the ink path side hole 16a, the ink path hole 15a,
Flow path common ink chamber 4, flow path space 3, ink jet nozzle 2
The ink flows through a series of ink paths. Note that the filter 8 is fixed inside the ink path of the helad case 12.

The embodiments shown in FIGS. 8(a) and 8(b) are shown in FIG.
Compared to the embodiments shown in FIGS. 7(a) and 7(b), this embodiment has the advantage that the nozzle side plate 14 is not required.

6(a)(b), 7(a)(b), 8th
In the embodiments shown in FIGS. (a) and (b), the members forming the ink path of the head case 12 can be directly connected to the channel substrate 1 without using the diaphragm 6, so the connection strength is dramatically increased.

In addition, by not using the diaphragm 6, the number of laminated components in the thickness direction can be reduced, the accuracy in the thickness direction between the connecting surfaces can be greatly improved, and the reliability of the seal can be dramatically improved.

Furthermore, the nozzle surface plate 14 in the embodiments shown in FIGS. 6(a), 7(b) and 7(a) and 7(b) is made of a metal material, and is spread over the entire nozzle surface except for the two ink jet nozzles. It is possible to prevent damage to the nozzle surface due to accidental paper rubbing when the printer is in a completed state.

In these embodiments, it is also effective to use the method shown in FIG. 6 in which the gasket 13a is held between the flow path substrate 1 and the tip of the ink path forming member of the helad case 12.

And, the above-mentioned FIGS. 6(a)(b) and 7(a)(b)
), In the embodiment shown in FIGS. 8(a) and 8(b), the method in which the member forming the ink path is directly connected to the flow path substrate 1 without using the diaphragm 6 is that the member forming the ink path is Figure 1,
The supply vibrator 7 shown in FIG. 2 is also effective. That is,
The ink paths inside the channel substrate 1 are shown in FIGS. 6(a) and 6(b),
This is the same as the embodiments shown in FIGS. 7(a) and 8(b), and FIGS. 8(a) and 8(b). Structures similar to the examples are also included in the structures of the present invention.

Next, in FIG. 9 and FIG. 10, an example regarding the fixing position of the filter 8 is shown. In FIG. 9, a filter 8 is fixed to the nozzle surface side of the head case connecting ink chamber 5a of the flow path substrate 1. In FIG.

This example is shown in FIGS. 6(a)(b) and 7(a)(b).
) can be combined with the embodiments.

In FIG. 10, a filter 8 is fixed to the side surface of the diaphragm 6 of the head case connecting ink chamber 5a of the flow path substrate 1. In FIG. This example is shown in Fig. 6(a)(b) and Fig. 7(a).
(b), and can be combined with the embodiments shown in FIGS. 8(a) and 8(b).

As another example, as shown in FIG. 11, a member is provided in which the ink path corresponding to the head case connection ink chamber 5a of the flow path board 1 is extended toward the side opposite to the nozzle surface, and the tip thereof is connected to the head case. It connects to the perforated surface of the 12 ink channels. The portion of the head case 12 in which the ink path has a hole is extended toward the side opposite to the nozzle surface.
The tip thereof has a shape to which an ink tube 9 can be connected or an ink supply needle 9a can be press-fitted therein.

Next, as another embodiment, as shown in FIG. 12, an ink tube 9 connection portion is formed in the head case 12. The space communicating with the ink tube connection portion of the head case 12 and the outer diameter of the member extending the ink path corresponding to the head case connection ink chamber 5a of the flow path board 1 toward the side opposite to the nozzle surface are defined by the gasket 13a. It is sealed by. Note that the filter 8 may be fixed to the tip of a member of the flow path substrate 1 that extends the ink path corresponding to the head case connection ink chamber 5a toward the side opposite to the nozzle surface. Further, at the tip of a member extending the ink path corresponding to the head case connecting ink chamber 5a of the flow path substrate 1 toward the opposite nozzle surface side, and at the surface of the head case 12 where the ink path hole is formed,
It is also effective to sandwich the gasket 13a in the thickness direction of the channel substrate 1.

In the embodiments shown in FIGS. 11 and 12, the ink paths inside the channel substrate 1 are shown in FIGS.
)(b), and the structures shown in the embodiments of FIGS. 8(a) and 8(b) are applicable, respectively.

As described above, in the structure of all the embodiments, the ink path inside the head up to the flow path substrate 1 is formed only by the supply pipe 7 or the members of the head case 12, so that it is possible to reduce the number of parts and ink. This leads to a reduction in connections in the route.

As shown in FIG. 13, the inkjet recording head shown in FIGS.
7, it is firmly attached by screwing or the like. ■Mouth,
The structure of all the embodiments described above is such that the tension applied to the head mounting portion of the ink tube 9 due to the mounting force of the ink tube 9 that transports ink from the ink storage system and the movement of the printer carriage 17 is transferred to the head case 12. Then Uke will be stopped by 8. Further, in the case of a type in which an ink storage system such as an ink cartridge is directly attached to the ink supply needle 9a of the inkjet recording head, the head case 12 can absorb the large attachment force applied during attachment. The force applied to these helad cases 12 is
Since the head case 12 is firmly connected to the printer carriage 17, it is supported by the printer carriage 17, which is extremely rigid in terms of the structure of the printer.

In other words, the structure of this embodiment prevents the influence of the force exerted on the ink system connection part, which causes disturbance, on the flow path space 3 that controls subtle pressure changes by supporting it with the head case 12 and the printer carriage 17. can. In addition, by supporting the extremely large force applied when installing the ink cartridge or connecting the ink tube 9 with the head case 12 and the printer carriage 17, the flow path board 1 or the connections between each component can be prevented from stacking or breaking. can be prevented.

[Effects of the Invention] As explained above, according to the present invention, the number of parts and manufacturing man-hours can be reduced by forming the ink path that supplies ink to the flow path space using the flow path substrate and the supply pipe or head case. It is possible to pursue cost benefits by reducing the number of connections in the ink supply path, improve reliability by reducing the number of connections in the ink supply path, and provide a highly reliable, low-cost inkjet recording head.

[Brief explanation of the drawing]

FIG. 1 is a front view of a channel substrate of an inkjet recording head of the present invention. FIG. 2, FIG. 3, FIG. 4, and FIG. 5 are longitudinal cross-sectional views of the inkjet recording head of the present invention. FIG. 6(a), FIG. 7(a), and FIG. 8(a) are partially enlarged views of the channel substrate of the inkjet recording head of the present invention. Also, Fig. 6(b), Fig. 7(b), Fig. 8(
b) shows the inkjet recording head of the present invention in FIG.
FIG. 89 is a partially enlarged vertical cross-sectional view corresponding to each of the embodiments in FIGS. Figure 9, 1st
0, FIG. 11, and FIG. 12 are partially enlarged longitudinal cross-sectional views of the inkjet recording head of the present invention. Further, FIG. 13 is a longitudinal sectional view of the inkjet recording head of the present invention when it is attached to a printer carriage. 5 a ・ 9 a ・ Flow path board Ink jet nozzle Flow path space Common Ink chamber for connecting the ink chamber Supply pipe Ink chamber for connecting the head case Ink chamber Vibration plate Supply pipe Filter Ink tube Ink supply needle Piezoelectric element PC Head case a a a...・ Packing Nozzle face plate Ink route through hole Ink route hole Nozzle side ink route Ink route Side hole Printer carriage Above Applicant: Seiko Epson Co., Ltd. Representative patent attorney Kizobe Suzuki et al.-8 Figure 1 Figure 5] $6 Figure (a) Figure 6 (b) Figure 7 (Q) Figure 7 (b Figure 8 (Q) Figure δCb) Figure 10 Figure 13

Claims (1)

[Claims] a flow path substrate and a diaphragm that form a flow path space that communicates with a plurality of ink ejection nozzles; a piezoelectric element that applies a pressure change to the flow path space; an electrical wiring system that transmits an ink ejection signal;
The inkjet recording head is configured with a head case that encloses the head components, and includes an ink path that supplies ink to the flow path space, from a connection part with an ink path outside the head to a flow path substrate inside the head. a supply pipe whose inner diameter forms an ink path;
Alternatively, an inkjet recording head characterized in that it is formed by the head case.