JP2814897B2 - Inkjet head cartridge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head cartridge used in an ink jet recording apparatus for performing recording by discharging ink.

[0002]

2. Description of the Related Art In recent years, an apparatus to which an ink jet recording apparatus is applied has become widespread, and a large number of ink jet cartridges in which a recording head and an ink tank are integrated have been introduced to the market. In actual products, an O-ring is often used as an ink leakage preventing means in an ink flow path connecting an ink tank and a recording head. If one ink jet cartridge has only one color of ink, there is no concern about color mixing in the ink flow path. For example, in an ink jet head cartridge in which a recording head of three colors of yellow, magenta, and cyan and an ink tank are integrated. In addition, there is a concern about a problem of color mixing at a connection portion of the ink flow path.

As a known ink jet head cartridge, for example, HEWLETT-PACKARD
JOURNAL, AUGUST 1992, VOLUM
E43, NUMBER 4, "Automatic As
sembly of the HP Desk Jet
500C / Desk writer C Color
As described in "Print Cartridge", there is an ink jet cartridge in which a recording head of three colors of yellow, magenta, and cyan and an ink tank are integrated, and this document reports on a joint portion of an ink flow path. According to the description of this document, color mixing in the ink flow path is eliminated by applying an adhesive around the supply ports of each of the three colors.

[0004] However, in this method, there is a concern that the flow of the adhesive is obstructed due to the overflow of the adhesive, thereby hindering the supply of ink. In order to prevent this, a high-precision adhesive application device is required, and an inspection process of the application state must be provided, leading to an increase in manufacturing cost.

[0005] In recent years, from the standpoint of environmental protection, resource saving, and the like, there is an increasing demand for recycling of products and parts. However, according to the means described in the above-mentioned document, the recording head and the ink tank can be integrated, but after collecting the ink jet cartridge, the recording head and the ink tank are individually separated and the optimum means for the demand for recycling. Was not. That is, since the recording head and the ink tank are adhered by the adhesive, there is a problem that the recording head and the ink tank cannot be separated.

As another countermeasure, it is conceivable that an O-ring or the like is independently attached to a connection portion of each ink flow path. Generally, if an O-ring is used, separation between ink flow paths for each color, prevention of ink leakage, and separation between the recording head and the ink tank can be simultaneously solved. However, due to restrictions on the size of the O-ring, the desired flow path diameter and flow path spacing could not be achieved, and the size could not be particularly reduced.

For example, in an ink jet print head described in Japanese Patent Application Laid-Open No. 1-110965, the ink in the ink tank is formed by compressing a front plate on a bead-shaped periphery provided on a sealing plate. The ink is supplied to the print head through an ink channel. In this example, the ink flow paths are connected at one location without using a sealing member such as an O-ring for each ink flow path. However, in such a configuration, separation of the recording head and the ink tank is not considered.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and separates the respective ink flow paths at a connecting portion between a recording head and an ink tank to prevent ink leakage. An object of the present invention is to provide an ink jet head cartridge in which this portion is reduced in size and the recording head and the ink tank can be separated.

[0009]

According to the present invention, there is provided an ink jet head having a recording head unit having an ink discharge section for discharging ink on one end side, and a plurality of ink tanks for supplying ink to the ink discharge section. In the cartridge, an elastic member provided at a connection portion between the ink tank and the recording head unit and having holes as many as the number of ink flow paths, and an ink flow path formed on a surface facing at least one surface of the elastic member. And a convex portion for isolating the target.

[0010] The recording apparatus further includes engaging means for engaging and holding the ink tank and the recording head unit. The engaging means connects the ink tank and the recording head unit, and connects the elastic member to the projection. It is characterized by pressing. The engaging means may be constituted by an elastically deformable claw portion and a fitting portion corresponding to the claw portion.

[0011]

According to the present invention, the elastic member is pressed against the protrusion provided on at least one of the ink tank side and the recording head unit at the connection portion between the ink tank and the recording head unit, so that the hermetic sealing is ensured. The effect can be obtained, so that problems such as ink leakage and ink mixing do not occur. The projections may be provided on both the ink tank side and the recording head unit side, and may be configured to be pressed by the projections from both sides of the elastic member, and a more reliable sealing effect can be obtained. The ink tank and the recording head unit are configured to be separable by a pressing part of the convex part against the elastic member. Further, the elastic member is provided with holes as many as the number of ink flow paths, so that a plurality of ink flow paths can be separated and sealed with one member, and the size can be easily reduced.

By providing an engagement means for engaging and holding the ink tank and the recording head unit, the pressing force is automatically applied to the elastic member at the same time when the ink tank and the recording head unit are connected. As engagement means,
By using the elastically deformable claw portion and the fitting portion corresponding to the claw portion, the ink tank and the recording head unit can be separated after the ink jet head cartridge is collected.

[0013]

1 and 2 show the construction of an ink tank unit in an embodiment of the ink jet head cartridge of the present invention. In the figure, 1 is an ink tank, 2 is a felt, 3 is a mesh member, 4 is a core material, 5 is a first bottom plate, 6 is a second bottom plate, 7 is a filter, 8 is a convex portion, 9 is a nail, 10 Is an elastic member, 11 is a top cover, 12 is an ink chamber, 13
Is a felt chamber, 14 is a fitting member, 15 is a slot, 16
Is an air communication hole. The illustrated ink tank unit has, as an example, a case in which three ink storage units are provided. For example, yellow,
Magenta and cyan inks can be filled in advance.

The ink tank 1 for storing ink includes an ink chamber 12 and a felt chamber 13 for each ink storage section.
Is divided into The ink chamber 12 stores ink. The felt chamber 13 holds the felt 2 for holding ink.
Is built-in. The felt chamber 13 and the ink chamber 1
2 is provided with a mesh member 3 and a core material 4. The ink chamber 12 and the felt chamber 13 communicate with each other via the mesh member 3. The core 4 supplies the ink in the ink chamber 12 to the mesh member 3. Thereby, the mesh member 3
Are always kept wet with ink.

The upper portion of the ink tank 1 has a top cover 1
1 is attached. The top cover 11 has a felt room 1
3 has an atmosphere communication hole 16 at an upper position. The upper portion of the ink chamber 12 is configured to seal the ink chamber 12 when the inkjet head cartridge is used,
For example, an opening for injecting ink at the time of manufacturing may be provided.

The bottom of the ink tank 1 is closed by a first bottom plate 5 and a second bottom plate 6. The first bottom plate 5 is provided with a hole for drawing out ink from each ink chamber 12 corresponding to each ink chamber 12.
Filters 7 for collecting dust in the ink are mounted. In the second bottom plate 6, an ink flow path derived from a hole provided in the first bottom plate 5 is formed, and ink flows between the first bottom plate 5 and the second bottom plate 6, It is led to a joint with a recording head unit (not shown). Second
At the joint of the bottom plate 6 with the recording head unit, holes are provided corresponding to the respective ink flow paths, and projections 8 are provided so as to isolate the holes. Further, a claw 9 is provided on the second bottom plate 6 to lock the recording head unit. On the other hand, the sheet-like elastic member 10 is provided with holes corresponding to the respective ink flow paths.
0 and the protruding portion 8 are in close contact with each other, and each ink flow path is sealed. First
The bottom plate 5, the second bottom plate 6, and the top cover 11 are respectively fixed by ultrasonic welding. The bonding means is not limited to the one by ultrasonic welding, and various methods such as a normal adhesive and heat fusion can be used.

The ink tank 1 is further provided with a slot 15 for accommodating an electric circuit portion of a recording head unit (not shown), for fixing the electric circuit portion when the recording head unit is mounted. Of the fitting member 14.

FIG. 3 is an enlarged view of the joint of the second bottom plate 6 with the recording head unit. The protrusions 8 provided on the second bottom plate 6 are provided so as to surround the holes provided corresponding to the respective ink flow paths, as shown in FIG. When the elastic member 10 is pressed against the convex portion 8, the sealing property of each ink flow path is improved. Thus, the ink in each of the ink flow paths does not mix and leak at the joint. Further, compared with the case where an O-ring or the like is used for each ink flow path, the interval between the ink flow paths can be narrowed and the size can be reduced.
Since a plurality of ink flow paths are connected using one elastic member 10, the number of components can be reduced.

FIGS. 4 and 5 are cross-sectional views of an embodiment of the ink jet head cartridge of the present invention. In the figure, the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted. Reference numeral 20 denotes an ink tank unit, 21 denotes a recording head unit, 22 denotes a connecting portion, 23 denotes a substrate, 24 denotes a heat sink, 25 denotes a manifold, 26 denotes a rib, 27 denotes a protrusion, and 28 denotes a print chip. FIG. 4 illustrates a state where the ink tank unit and the recording head unit are separated, and FIG. 5 illustrates a state where the ink tank unit and the recording head unit are integrated.

The recording head unit 21 supplies a printing chip 28 for discharging ink, a substrate 23 for transmitting an electric signal to the printing chip 28, a heat sink 24 for radiating heat generated by the printing chip 28, and a supply of ink to the printing chip 28. Of the manifold 25. Print tip 28
For example, may be configured to have a plurality of nozzles for ink ejection corresponding to each ink. A plurality of manifolds 25 are provided corresponding to each ink flow path. Ink tank unit 2 of manifold 25
The connecting portion 22 on the 0 side has a protrusion 27 for pressing the elastic member 10. The protrusion 27 is provided so as to isolate each ink flow path, similarly to the protrusion 8 of the ink tank unit 20. In addition, a rib 26 that fits with the claw 9 of the ink tank unit 20 is provided.

When such a recording head unit 21 and the ink tank unit 20 described with reference to FIGS. 1 to 3 are connected to each other with the elastic member 10 interposed therebetween, an ink jet head cartridge is completed as shown in FIG. That is, the protrusion 8 of the ink tank unit 20 is
, And a projection 27 provided on the connecting portion 22 of the recording head unit 21 abuts on the surface on the opposite side of the elastic member 10. Further, by pressing the recording head unit 21 and the ink tank unit 20 against each other, the claw 9 having elastic force is fitted to the rib 26, and the elastic member 10 is maintained in a state of being pressed by the projection 8 and the projection 27. Will be done. As a result, the joint between the ink tank unit 20 and the elastic member 10 and the joint between the recording head unit 21 and the elastic member 10 are sealed for each ink flow path to prevent ink leakage and ink mixing. No failures occur.

When the ink tank unit 20 and the recording head unit 21 are connected, the substrate 23 and the heat sink 24 are inserted into the slots 5. Then, the fitting member 14 provided on the ink tank unit 20 fits into the hole provided on the heat sink 24, and the ink tank unit 20 and the recording head unit 21 are also connected at this portion. At this time, the substrate 23 is electrically connected to a terminal plate (not shown) provided in the ink tank 1. The terminal plate is electrically connected to the ink jet recording apparatus when the ink jet head cartridge is mounted on the ink jet recording apparatus, and exchanges print data and exchanges control signals.

When the ink-jet head cartridge is used, the ink is exhausted, the used ink cartridge is used, and the ink tank unit 20, the elastic member 10, and the recording head unit 21 are disassembled by opening the claw 9 and the fitting member 14. Is done. Thereby, for example, the reusable recording head unit 21 is mounted on a new ink tank unit via a new elastic member, and is used again as an ink jet head cartridge, or conversely, the ink tank unit 20 is filled with ink again. Then, it is possible to recycle parts, for example, by replacing the deteriorated recording head unit and the elastic member with new ones and using them again as ink jet head cartridges. This allows
Resources can be saved, the price of the inkjet head cartridge can be reduced, and the running cost of the inkjet recording apparatus can be reduced.

In the above example, the ink tank unit 20
Although the projections 8 and the projections 27 are provided on both the recording head unit 21 side and the recording head unit 21 side, it is also possible to configure only one of them. For example, the protrusion 8 is provided, and the elastic member 10 is connected to the connecting portion 2.
2 and can be configured. Also, the elastic member 1
0 may be bonded to the second bottom plate 6 and pressed against the protrusion 27.

The projection 8 and the projection 27 can have a triangular cross section. With this configuration, since the vertices of the triangle are pressed against the elastic member 10, the pressure is concentrated on the vertices, and the sealing performance by pressing is further improved. Of course, other cross-sectional shapes may be used.

FIG. 6 is a schematic illustration of an example of the ink supply operation in one embodiment of the ink jet head cartridge of the present invention. The symbols in the figures are the same as those in the above-mentioned figures. FIG. 6A shows the state when the ink is full. In this state, the ink chamber 13 is filled with almost 100% ink, and the felt chamber 13 is filled with ink to the limit that can be held by the capillary force of the felt 2 inside. In this state, the ink is held by the capillary force of the felt 2 and is kept at a negative pressure.

When printing starts, ink is consumed by the print chip 28, and the amount of the consumed ink in the ink chamber 12 is reduced.
From the print chip 28 through the manifold 25
Resupplied to Accordingly, while the ink is held by the felt 2, the ink is discharged from the felt 2 to the ink chamber 12.
The air gradually moves from the atmosphere communication hole 16 to the felt 2
It spreads to. At this time, ink is supplied to the print chip 28 at a stable negative pressure by the capillary force of the felt 2.

When the ink in the felt chamber 13 is almost consumed, the air reaches the surface of the mesh member 3. When the ink is further consumed, a certain negative pressure value (the bubble point pressure of the ink determined by the filtration accuracy of the mesh member 3)
Is applied to the mesh member 3, air becomes bubbles through the meniscus of the ink formed on the mesh member 3 and enters the ink chamber 12. The negative pressure in the ink chamber 12 is reduced by the amount of the bubbles. This state is shown in FIG.
By repeating this operation, the ink chamber 12 and the print chip 2 are kept until the ink in the ink chamber 12 runs out.
8 is maintained at a substantially constant negative pressure.

When bubbles are generated in the mesh member 3 and the bubbles stay on the surface of the mesh member 3, there is a possibility that a meniscus of the ink may not be formed on the mesh member 3. Since the core 4 is always in contact with the ink in the ink chamber 12, the core 4
The ink is supplied to the mesh member 3 by the capillary force, and the mesh member 3 is always kept wet with the ink, and the meniscus of the ink is not broken.

The surrounding environment may change, for example, when the outside air pressure fluctuates or the outside air temperature fluctuates. First, when the main ink chamber is fully filled with ink and ink is being supplied from the sub ink chamber, the atmospheric pressure received by the absorbing member 9 from the atmosphere communication hole and the large pressure received by the tip of the nozzle of the inkjet head 1 become large. Since the atmospheric pressure is the same, even if the atmospheric pressure changes, the pressure balance does not collapse and the influence is small.

Next, consider a case where an air layer is formed in the main ink chamber. When the outside air pressure falls or the outside air temperature rises, the volume of the air layer above the ink chamber 12 expands, so that the negative pressure value in the ink chamber 12 tends to become relatively small. Therefore, as shown in FIG. 6C, the ink in the main ink chamber 4 passes through the mesh member 3 and is held by the felt 2 in the felt chamber 13. Thus, the pressure difference between the pressure in the main ink chamber 4 and the atmospheric pressure is maintained, and the ink does not leak. At this time, since the filtering particle size of the filter 7 is smaller than that of the mesh member 3,
Ink does not leak from the inkjet head 1 through the filter 7.

When the outside air pressure rises or the outside air temperature falls, the air layer above the ink chamber 12 contracts, so that the negative pressure value in the main ink chamber 4 will become relatively large. I do. In this case, as in the case of ink consumption, as shown in FIG. 6B, air is introduced into the ink chamber 12 to keep the negative pressure inside the ink chamber 12 constant. When ink is present in the felt chamber 13, the ink moves to the ink chamber 12 and the ink chamber 1
The negative pressure in 2 is maintained. In either case, no ink leaks.

In the above description, an ink tank unit having a structure in which two ink chambers and a felt chamber are provided as a plurality of ink storage chambers has been described.
The present invention can be similarly applied to a case where an ink tank unit including only ink chambers is used. Also, the present invention can be similarly applied to an ink tank unit using an ink storage chamber of another configuration that does not use the mesh member 3 and the core member 4 even if it has a two-chamber configuration. Thus, regardless of the configuration of the ink tank unit,
The present invention can be applied.

[0034]

As is apparent from the above description, according to the present invention, with a simple structure, it is possible to prevent a problem such as ink leakage or mixing at the connection portion between the recording head and the ink tank, and to reduce this portion. The size can be reduced. Further, since the recording head and the ink tank can be configured to be separable, there is an effect that the recording head can be separated after collection and individually recyclable.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an ink tank unit in one embodiment of an inkjet head cartridge of the present invention.

FIG. 2 is a configuration diagram of an ink tank unit in one embodiment of the inkjet head cartridge of the present invention.

FIG. 3 is an enlarged view of a joint portion between a second bottom plate 6 and a recording head unit.

FIG. 4 is a cross-sectional view of one embodiment of the ink jet head cartridge of the present invention at the time of separation.

FIG. 5 is a cross-sectional view of the ink jet head cartridge according to the embodiment of the present invention at the time of connection.

FIG. 6 is a schematic diagram illustrating an example of an ink supply operation in an embodiment of the inkjet head cartridge of the present invention.

[Explanation of symbols]

1 ink tank, 2 felt, 3 mesh members, 4
Core material, 5 first bottom plate, 6 second bottom plate, 7 filter, 8 convex portion, 9 nail, 10 elastic member, 11 top cover, 12 ink chamber, 13 felt chamber, 14 fitting member, 15 slot, 16 Atmospheric communication hole, 20 ink tank unit, 21 recording head unit, 22
Connection part, 23 substrates, 24 heat sinks, 25 manifolds, 26 ribs, 27 protrusions, 28 print chips.

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 2/175

Claims (3)

(57) [Claims] 1. An ink jet head cartridge having a recording head unit having an ink ejection section for ejecting ink on one end side and a plurality of ink tanks for supplying ink to the ink ejection section. An elastic member provided in the connection portion of the recording head unit and having holes formed in the number of ink passages, and a convex portion for isolating the ink passage on a surface facing at least one surface of the elastic member. An inkjet head cartridge comprising: 2. An ink jet printer according to claim 1, further comprising an engaging means for engaging and holding said ink tank and said recording head unit. The engaging means connects the ink tank and the recording head unit and presses the elastic member against the convex portion. The ink jet head cartridge according to claim 1, wherein: 3. The ink jet head cartridge according to claim 2, wherein said engaging means comprises an elastically deformable claw portion and a fitting portion corresponding to said claw portion.