JPH0536689Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Technical Field] The present invention relates to an inkjet cartridge. [Prior art] The inkjet recording method (liquid jet recording method) is
It has recently attracted attention because it generates negligible noise during recording, is capable of high-speed recording, and can be recorded without the need for special processing such as fixing on plain paper. There is. Among them, for example, the liquid jet recording method described in Japanese Unexamined Patent Publication No. 54-51837 and German Publication of Publication (DOLS) No. 2843064 applies thermal energy to the liquid to obtain the motive force for ejecting droplets. In this respect, it has different characteristics from other liquid jet recording methods. In other words, the recording method disclosed in the above gazette is
The liquid subjected to the action of thermal energy undergoes a state change accompanied by a sharp increase in volume, and the acting force based on this state change causes the liquid to be ejected from the orifice at the tip of the recording head, forming flying droplets. is formed,
The droplets adhere to the recording member and recording is performed. In particular, the liquid jet recording method disclosed in German Publication No. 2843064 is not only very effectively applied to the so-called drop-on-demand recording method, but also has a full-line type recording head with high-density multi-layer recording. Since an orifice-shaped recording head can be easily implemented, it has the characteristic that high-resolution, high-quality images can be obtained at high speed. The recording head part of the apparatus applied to the above recording method is a part that communicates with an orifice provided for ejecting liquid and where thermal energy acts on the liquid in order to eject droplets. The apparatus includes a liquid discharge part having a liquid flow path in which a heat acting part is a part of the structure, and an electrothermal converter as a means for generating thermal energy. Conventionally, in a recording apparatus using such a liquid jet recording head, the recording liquid necessary for recording is collected from a recording liquid storage section (ink tank) provided at a location separate from the recording head through a flexible pipe or the like. The electric signal for driving the electrothermal transducer of the recording head is supplied via a flexible wiring cable from the drive circuit provided at a location separate from the recording head. It was beginning to be supplied. In conventional ink containers, the ink container that stores ink, which is the recording liquid, has a ventilation hole or is made of a flexible material and is sealed. The ink pressure is always maintained at atmospheric pressure. The ink container is connected to a recording head through an ink supply tube, and flying droplets are formed by electrically and mechanically driving the recording head.
A conceptual diagram of the structure of the above ink container is shown in Figures 1a and b.
Shown below. In FIGS. 1a and 1b, 101 is a recording head, 102 is an ejection port, 103 is an ink supply pipe,
104 is an ink container, 105 is a ventilation hole, 106 is a flexible ink container, 107 is ink, and 108 is an ink water head difference. The ink 107 is filled from the ink container 104 or the flexible ink container 106 to the ejection port 102, and the ink 107 formed in the ejection port 102 is filled with ink 107.
The surface tension of the meniscus causes the recording head 101 to
held within. Since the ink retention force due to this surface tension is small, an ink water head difference 108 as shown in FIGS. 1a and 1b is further set, and the pressure applied to the meniscus of the ejection port 102 is set as negative pressure. This also contributes to stability during liquid ejection of ink. For this reason, in the ink supply system of conventional inkjet recording devices, it is necessary to provide a water head difference between the ink discharge port and the ink liquid level in the ink container in order to maintain the appropriate ink supply pressure to the print head discharge port. However, the position of the ink container relative to the recording head within the ink container is limited, and the shape of the ink container must be made flat and thin to reduce the influence of changes in the liquid level within the ink container. This was a major constraint on the design of ink containers. Furthermore, in the case of this type of system, if the entire ink container is placed on an inclined surface or tilted during movement, the head difference between the recording head ejection opening and the liquid level in the ink container will easily change. Problems such as leakage of ink from the ejection port and air bubbles being drawn into the ejection port may occur, and great care must be taken when handling the device. On the other hand, the ink container is made of an elastic material, has the function of generating negative pressure, is integrated with the recording head, and is configured to balance the ejection orifice meniscus, and is detachable from the recording device. There is an inkjet cartridge that can be used. In such an ink jet cartridge, the ink water head difference is always approximately 0, and instead, the elastic force of the ink container is used to apply negative pressure to the ink. Inkjet cartridges having such a structure are shown in FIGS. 2a, b, c, and d.
FIG. 2a shows an outline of the ink container, and FIG. 2b schematically shows the cross section AA' in FIG. Also, Figure 2c
is the XX' cross section shown in FIG. 2b, and shows the initial state where the ink is almost completely filled. Here, 201 is a recording head section, 202 is an ejection orifice, 203 is an orifice plate, 2
04 is a spacer, 205 is a substrate, 206 is a heating resistor, 207 is a cover, 208 is an ink supply port, 209 is a protective cover, 210 is an ink container,
211 is ink, and 212 is a vent. The recording head section 201 converts electrical energy into thermal energy using a heat generating resistor 206, and the discharge orifice 202 on an orifice plate 203 provided opposite to the heat generating resistor 206 on a substrate 205 is activated by the action of the thermal energy. Ink 211, which is a recording liquid, is ejected to form flying droplets. The ink container included in an inkjet cartridge with such a configuration has a uniform wall thickness, so as the amount of ink in the ink container decreases due to consumption during recording, the negative pressure generated in the ink container gradually decreases. It was getting bigger. Therefore,
As shown in Figure 2 d and Figure 2 e showing the XX' cross section in Figure 2 d, when ink remains in the ink container, the pressure relationship with the ejection port collapses, and the ink supply is insufficient. In some cases, it was difficult to maintain normal records. [Purpose] The purpose of the present invention is to eliminate the drawbacks of the above-mentioned conventional examples, eliminate design constraints on the installation location of the ink container and the shape of the ink container, and eliminate the ink supply pressure applied to the recording head ejection port from remaining in the ink container. The present invention aims to maintain a substantially constant state regardless of the amount of ink used, stabilize the ejection of ink droplets during recording operation of the ink container, facilitate handling of the recording device, and further improve the ink consumption rate. It's about trying. Still another object of the present invention is to provide an inexpensive and reliable inkjet cartridge in which an ink container is integrated with a substrate having a heat generating section and an orifice section. Yet another object of the present invention is to provide an economical ink jet cartridge that minimizes the amount of ink that cannot be consumed and ultimately remains in the ink container. The present invention has been proposed to achieve the above-mentioned object, and has one end open and the other end closed, which stores ink to be supplied to a recording head equipped with an ejection port for ejecting ink. In addition, an ink storage member constituted by a bag-like flexible container that generates negative pressure involved in ink supply, and an ink storage member with an open end connected to an ink supply section to the recording head section. In the inkjet cartridge, which is removably attached to a recording apparatus, the inkjet cartridge is removable from a recording device, and includes a cartridge housing having a communication port part communicating with the atmosphere, wherein the ink storage member is made of one component. A plurality of vein-like thick film regions provided along the ink flow direction toward the ink supply section on the open end side, and a plurality of thin film regions connecting the vein-like thick film regions. and
The plurality of thin film regions are characterized in that they are substantially evenly compressed inward as the ink is consumed. According to the present invention, a plurality of vein-shaped thick film regions provided along the ink flow direction are provided with a negative pressure generation function related to ink supply, and a plurality of thin film regions connecting the vein-shaped thick film regions are provided with a negative pressure generating function that is involved in ink supply. By providing an ink supply function that collapses inward substantially evenly as the ink is consumed, stable ink supply with well-balanced ink consumption efficiency can be achieved. [Example] Hereinafter, the present invention will be explained in detail using the drawings. Figures 3a, b, c and d show embodiments of the invention. Figures 3a and c correspond to the AA' section in Figure 2a, and Figures 3b and d correspond to the AA' section in Figure 2a and b.
Corresponds to the XX′ cross-sectional view. and Figure 3 a and b
3 shows a state in which the ink container is almost full, and FIGS. 3c and 3d show the state of the ink container when the negative pressure inside the tank becomes large after ink has been consumed, resulting in poor printing quality. In the figure, 307 is a cover, 308 is an ink supply port formed in the cover 307, 309 is a protective cover to which the cover 307 is attached, 310 is an ink container provided in the protective cover 309, 311 is ink in the ink container 310, 312 is a vent provided in the protective cover 309. Ink container 310
has one end open so as to communicate with the ink supply port 308 and the other end closed in a substantially dome shape, and is itself a flexible container that has elasticity and generates negative pressure. The wall thickness in the peripheral area is partially reduced. Therefore, the ink container 31
0, a partial collapse occurs in which a substantially constant negative pressure can be maintained even when the ink 311 is consumed due to the presence of a region with a partial thin wall thickness. Note that here, 310a is a thin wall thickness part of the peripheral surface area of the ink container 310, and 310b is a thin part of the ink container 310.
This is the thick part of the wall. In this embodiment, the thick wall portions are formed in a vein shape along the ink flow direction. In this embodiment as well, when the ink is full, it is possible to store the same amount of ink as in the conventional example shown in FIG. 2b. As the ink is consumed, as shown in FIGS. 3c and 3d, the thin walled portion 310 of the ink container 310
However, since it is inserted into the ink container 310 like folding an umbrella, the amount of ink left in the ink container 310 can be extremely reduced. As mentioned above, by using an elastic membrane in the ink container, partially thinning the thickness, and actively crushing the thinned portion as the ink is consumed to maintain a nearly constant negative pressure, ink can be efficiently used. It became possible to consume. This will be explained more specifically by the following examples. That is, as an example, an ink container having the ink container shown in FIG. 3 was prepared, and a printing test was actually conducted. The initial amount of ink was 5 ml, and the number of sheets of A4 paper that could be correctly printed was measured, or the amount of ink remaining when printing problems occurred. The results are shown in Table 1. As a comparative example, an ink container shown in FIG. 2 in which the wall thickness of the ink container was uniform was used. As is clear from Table 1, in the example, printing was possible with up to 0.4 ml of ink remaining, whereas in the comparative example, printing failure occurred with as much as 1.7 ml remaining. The number of A4 paper sheets printed was approximately 400 or more in the example, while it was approximately 300 in the comparative example. In other words, in the ink container adopting the configuration of the present invention, the amount of remaining ink is less than 10% of the initial amount of ink, and the ink usage efficiency is significantly improved compared to an ink container with a uniform thickness. That is, according to the configuration of the present invention, as the ink is supplied, the thin part of the wall actively collapses and moves inward of the ink container, so that the ink accommodating portion is well contracted, so that the ink is consumption efficiency of
It is possible to reduce the amount to 10% or less.

[Table] [Effects] As described above, the ink storage member is composed of a plurality of vein-like thick film regions along the ink flow direction toward the ink supply section and a plurality of thin film regions connecting the vein-like thick film regions. By doing so, firstly, the vein-like thick film region exhibits the function of maintaining a constant negative pressure regardless of ink consumption, and secondly, the thin film region actively maintains a constant negative pressure as ink is consumed. The ink supply function can be exerted by collapsing evenly inward. Therefore, the amount of ink consumed in the ink storage member can be increased, and the ink consumption efficiency is excellent.
A cartridge that facilitates handling of a recording device can be provided.

[Brief explanation of the drawing]

Figure 1 a, b and Figure 2 b, c, d and e
2 is a schematic sectional view of a conventional ink container, FIG. 2a is a perspective view of the same device, and FIGS. 3a, b, c, and d are sectional views showing an embodiment of the present invention. 101... Recording head section, 102... Discharge orifice, 103... Ink supply pipe, 104... Ink container, 105... Vent hole, 106... Flexible ink container, 107... Ink, 108... Water head Difference, 201... Recording head section, 202... Discharge orifice, 203... Orifice plate, 20
4...Spacer, 205...Substrate, 206...
Heat generating resistor, 207, 307...Cover, 20
8,308...Ink supply port, 209,309...
...protective cover, 210,310...ink container,
211,311...ink, 212,312...
Ventilation port, 310a... Portion where the wall thickness of the ink container is thin, 310b... Portion where the wall thickness of the ink container is thick.

Claims (1)

[Claims for Utility Model Registration] A recording head that stores ink to be supplied to a recording head equipped with an ejection port for ejecting ink, has one end open and the other end closed, and has a negative pressure involved in ink supply. an ink storage member composed of a resulting bag-like flexible container; the ink storage member is housed with its open end connected to an ink supply section to the recording head section, and a portion thereof communicates with the atmosphere; In an inkjet cartridge that is removably attached to a recording device, the cartridge housing has a communication port, and the ink storage member is made of one component, and the ink storage member is made of one component, and the ink storage member is made of one component, and The device includes a plurality of vein-like thick film regions provided along the ink flow direction toward the ink supply section, and a plurality of thin film regions connecting the vein-like thick film regions, and the plurality of thin film regions are ink flow directions. An inkjet cartridge characterized by substantially uniformly collapsing inward as the inkjet cartridge is consumed.