TW579333B - Liquid/gas interface maintaining device - Google Patents

Abstract

This invention relates to a liquid/gas interface maintaining device to be implemented in ink cartridges, including an air drawing port and an ink collecting trough provided in an ink cartridge and in communication with each other, where capillarity is used to cause ink in the ink cartridge to be filled into the air drawing port and cohered to the surface of the ink collecting trough so as to form a liquid/gas interface that serves as an air supplying passage between the ink cartridge and the exterior thereby preventing improper entering of exterior air into the ink cartridge to allow appropriate regulation of negative pressure within the ink cartridge.

Description

579333 V. Description of the invention (1) [Field of the invention] The present invention is a liquid-gas interface maintenance device, which is applied to the ink tank of an inkjet printer to maintain a proper negative pressure value inside the ink tank. BACKGROUND OF THE INVENTION Inkjet printers have been a fairly reliable and efficient printing tool. Generally, inkjet printers have an inkjet printhead that moves back and forth relative to the surface to be printed and ejects ink droplets. A control system moves the inkjet print head to an appropriate position and then ejects the ink droplets, and the ink droplets land on the printing surface to form a desired image or data content. This type of printer usually uses an ink pen (ink pen), which mainly includes two parts: an ink cartridge that stores and supplies ink, and an inkjet print head. The inkjet print head is generally provided with a plurality of micro holes (or i f i ce), and each micro hole has its associated ink chamber (i n k c h a m b e r). In operation, ink is introduced from the ink cartridge into the ink chamber of the inkjet print head, and then ink droplets are ejected from the micro holes toward the target surface to be printed. If the pressure inside the ink cartridge is equal to the atmospheric pressure, the ink will leak from the micro holes, which will cause the ink droplets to fall out of position, which will affect the printing quality. In order to solve this problem, a slight negative pressure (s i i ght backpressure) must be maintained in the ink tank, so that the ink in the ink cartridge does not leak out of the micro holes when the inkjet print head is paused or stopped. In the following, the so-called negative pressure means that the pressure inside the ink cartridge is smaller than the pressure difference when the external air (amb i en t a i r). Sufficient negative pressure must be maintained inside the ink cartridge to prevent ink from leaking through the micro holes in the inkjet print head. However, if the negative pressure is too large, it will offset the ink droplets ejected from the inkjet print head.

Page 4 579333 V. Invention description (2) The possible impact of the printing power includes: making the size of the discharged ink droplets unable to maintain stability or gradually becoming smaller, making the quality of the printing worse, and in severe cases, it may even cause Ink droplets cannot be completely ejected. Therefore, in order to maintain normal operation, the negative pressure value must always be maintained within an operable range. That is, the negative pressure must be greater than the pressure value that prevents ink from leaking from the inkjet print head, and at the same time, it must be less than the pressure value that may prevent printing. In order to meet the above restrictions at the same time, there are many different technologies for different levels of product demands. In the literature, the negative pressure is mostly achieved by two devices, one for forming a proper negative pressure and the other for maintaining the negative pressure in a proper range. One of the above may be an elastic retractable bag, which changes the internal volume of itself to form a proper negative pressure in the ink cartridge during the use of the ink cartridge. The other negative pressure regulator (bubb 1 e genera tor) is The air-filling hole provided at the bottom of the ink cartridge uses a capillary phenomenon to form a liquid-air interface to prevent improper entry of outside air. In the case where the negative pressure in the ink cartridge increases significantly, the negative pressure generated by the elastic retractable bag follows With the increase of the amount of ejected ink, the air supply hole will be automatically opened (the external pressure overcomes the force of the capillary phenomenon), and a small amount of external air is introduced into the ink cartridge as a bubble to reduce the negative pressure to an appropriate level. Then, re-establish the liquid-gas interface—the gas-supply interface that connects the ink cartridge to the external liquid—to avoid excessive outside air from entering. In addition, general negative pressure regulators must meet certain conditions. The first condition is that the negative pressure regulator must be sufficient to accurately control the negative pressure. The second condition is that the smaller the negative pressure fluctuation in the ink tank, the better. In other words, when

Page 579333 V. Explanation of the invention (3) When the air bubble enters the inside of the ink tank, the negative pressure will drop. The negative pressure regulator must be able to quickly recover the liquid-air interface and prevent the continuous entry of air to maintain the proper negative pressure inside the ink tank. Pressure. The third condition is that the negative pressure regulator must have self-wetting ability (Wetting, so that the cohesion of the liquid is less than the adhesion to form a liquid-air interface). And the liquid-air interface must be sufficient to prevent air bubbles from entering, even when the ink inside the ink cartridge has been used up, or when the ink cartridge is inverted or tilted, and the negative pressure regulator is not submerged by the ink. The two devices mentioned above can be found in US Patent Nos. 5526030, 6186620 and 6213598. However, the negative pressure regulators disclosed in these patents need to use more than two components to achieve negative pressure regulation. Function, so it has complex structure, inconvenient manufacturing, and lack of space affecting ink storage in the ink cartridge. Therefore, a liquid-gas interface maintenance device is designed to achieve the function of negative pressure adjustment through a relatively small number of components and increase manufacturing The convenience and the increase of ink storage space are really important. [Objective and Summary of the Invention] The main object of the present invention is to provide a liquid-gas interface maintenance device to prevent gas from entering the ink cartridge improperly, and then to adjust the proper negative pressure inside the ink cartridge. Affects the proper negative pressure inside the ink cartridge. The liquid-gas interface maintaining device disclosed in the present invention is applied to an ink cartridge. The device includes an air-filling hole and an ink collecting tank, wherein the air-filling hole is provided in the ink cartridge, and the ink is filled therein by capillary phenomenon, and The ink tank is arranged on the ink tank, and communicates with the air supply hole together with the air outside the ink tank. The surface of the ink collection tank is attached with ink to form a liquid with the ink in the air supply hole.

Page 6 579333 V. Description of the invention (4) Air interface, so that the supplementary gas passage (liquid-air interface) that allows the ink cartridge to communicate with outside air can prevent gas from entering the ink cartridge improperly, and adjust the proper negative pressure inside the ink cartridge. In addition, the surface of the ink collecting tank can be treated as a hydrophilic surface, so that the capillary force of the ink is increased, and the ability of the ink to wet (W e 11 ing) the surface of the ink collecting tank is increased to make the surface of the ink collecting tank easy to wet. The surface is roughened, a hydrophilic agent is coated on the surface of the ink collecting tank, and the material of the ink collecting tank is a hydrophilic material. In order to further understand the purpose, structural features, and functions of the present invention, detailed descriptions with the drawings are as follows:

[Detailed description of the embodiment]

The liquid-gas interface maintaining device disclosed in the present invention is applied to the ink cartridge 1. As shown in "Figure 1" and "Figure 2", the liquid-gas interface maintaining device is disposed at the bottom of the ink cartridge 1, including: The air supply hole 10 and the ink collecting tank 20 are provided at the bottom of the ink tank 1, and the air supply hole 10 is also provided at the bottom of the ink tank 1, and communicates with the outside of the ink tank 1 and the ink collecting tank 20, The ink communicates with the air supply hole 10 and the ink collection tank 20 by capillary force, forms a gas supply passage (liquid-air interface) between the air supply hole 10 and the outside of the ink cartridge 1, and makes the ink attached to the ink collection tank 2 0 The supply of ink in the air supply hole 10 can be ensured, so the air supply channel that communicates the ink cartridge 1 with external air can prevent the gas from entering the ink cartridge 1 improperly, whether the ink cartridge 1 is upright, inverted or inclined. The proper negative pressure inside the ink cartridge 1 is adjusted. As shown in "Figure 3A", when the ink tank 1 is upright, the ink in the ink tank 1 closes the air supply hole 10 and the ink collecting tank 20 to form a liquid-air interface due to gravity, thereby preventing the ink S 1 Outside gas enters improperly, so can

Page 7 579333 V. Description of the invention (5) It is enough to keep the proper negative pressure in the ink cartridge 1, and as shown in "Figure 3B", during the use of the ink cartridge, the ink cartridge 1 is gradually reduced due to the ink. When the negative pressure in the medium increases, the air outside the ink tank 1 also enters the ink tank 1 through the ink collection tank 20 through the air supply hole 10 through the air supply hole 10, thereby changing the negative pressure in the ink tank 1. As shown in "Figure 2", when the ink tank 1 is inverted (or tilted), the ink in the ink tank 1 flows to the near-ground end near the ink tank 1 due to gravity, but because the ink is in the The capillary phenomenon in the air supply hole 10 and the ink adhere to the ink collection tank 20, thus forming a liquid-air interface, and the air supply hole 10 and the ink collection tank 20 are closed. The design of the ink collection tank 20 must be able to be maintained at any time. Sufficient ink to prevent the ink adhering to the air supply hole 10 from being pushed back by the gas entering the ink cartridge 1 from the outside, and thus the liquid-gas interface is lost. The shape of the above-mentioned supplementary air hole 10 can be rectangular, circular, polygonal, star-shaped, irregular, etc. Among them, non-circular ones are preferred, such as the non-circular ink collection tank shown in FIG. 4 20, because the gas entering the ink cartridge 1 in the form of a bubble 30 is round, so non-circular ones have a backfill angle 11 that will not be filled by the bubble 30, and is located at the edge of the air supply hole 10, this backfill angle The angle of 1 1 is smaller than the flat angle, and a smaller angle is better, so that the gas of the type of bubble 30 enters the ink tank 1 through the air supply hole 10 and the ink tank 1 has reached a proper negative pressure value. , The ink can be quickly backfilled to the make-up hole 10. The shape of the ink collection tank 20 described above can be rectangular, circular, convex polygon, star, irregular, or even radial, etc., and its surface can be treated as a hydrophilic surface to increase ink wetting ( We 11 i ng) the ability of the ink collecting tank 20 to improve the adhesion of the ink, so that the surface of the ink collecting tank 20 can be easily wetted.

579333 —— V. Description of the invention (6) The method of T is to roughen the surface of the ink collecting tank 20, apply a hydrophilic agent to the surface of the ink collecting tank 20 and the material of the ink collecting tank 20 is a hydrophilic material. In addition, when the shape of the joint 20 is circular, the air supply hole 10 is easy to be filled with air bubbles; 20 is easily filled with bubbles in a stable state *, and the surgery & gift interface is easy to make the ink ... the gas enters the second and second. When the water is at a negative pressure, when the shape of the ink collecting tank 20 is non-circular, it has an attachment loss angle 21 located at the side end, and the ink collecting tank 2 is attached. Angle, ... The angle is better to make the ink 3, angle; = the surface and the surface of the bubble include at least one ink flow between the ink tank 20 and the air supply hole 10 flow. In order to let the ink gather, as shown in "Figure 5", when the ink collection tank 20 is backfilled with ink to the air supply hole, the ink flows radially toward the air supply hole 10, and the ink collection tank 2.1: = Ink collecting tank 20 Quickly dislodging member 22 placed on the side of ink collecting tank 20 (eg. Fig. 2 is near gas supply hole 10 and groove 2 is set. The sharp points on the sides are, but the same can be set radially. The ink hinders the formation of the liquid-gas interface, and even if the gas is above 10, l-Jr S -ΤΓ Ί 3 0 is located here 'under the material source element =, the bubble 30 will move to other positions. 隹 隹 ^ 政 ▲ '-',:, The shape is one of the convex polygons with the ancient / 隹 ^, to the same fruit, but 卩 "* ^: shape: the ink tank 20 can also reach large bubbles, it is not easy to die in this shape ^ ^ ^ "The larger one is better, because the bubble has two stickers and ^ eight, there are two sticking faces, and the lower ends of the two sides are sticking faces, so the air supply hole 10 is blocked by the bubble 30 Opportunity ^ Low 弁 Xi 'and this type of ink collecting tank 20 can also increase the ink backfill to replenish air; heart 579333 V. The speed in the description of invention (7). As shown in "Figure 6", the ink collecting tank 20 Drive off 2 2 can also be the one adjacent to the air supply hole 10 and set on the bottom surface of the ink collection tank 20, and the drive member 2 2 can be a convex point or a sharp point, so that the gas passing through the bubble type enters the ink cartridge through the air supply hole 10 At 1 o'clock, stay away from the air-supply hole 10, and do not block above the air-supply hole 10 to prevent the formation of the liquid-air interface. As shown in "Figure 7", the bottom surface of the ink collection tank 20 can be designed as the air-supply hole 10 The position is the relatively low point (or the lowest point) of the entire ink collection tank 20, increasing the efficiency of ink replenishment to the air supply hole 10, and guiding the bubble 30 to move away from the air supply hole 10, without Blocking above the air-filling hole 10 prevents the formation of the liquid-air interface. Another preferred position of the air-filling hole 10 is located in the center of the ink collecting tank 20, and the distance from the edge is greater than 1/3 to 2/3 of the boundary length or It is 1/5 ~ 4 / 5. [Achieved effect] The present invention is a liquid-gas interface maintenance device, which has the following effects: 1. Simple structure: The present invention only needs to pass through the air-filling holes provided on the bottom surface of the ink cartridge. And the ink collection tank, the effect of maintaining the negative pressure in the ink cartridge can be achieved. 2. Convenient manufacturing: the air supply hole of the present invention And the ink collecting tank is integrally formed at the same time as the ink cartridge is ejected, which can increase the convenience of manufacturing. 3. Increase the ink storage space: because the number of components of the conventional technology is large, and the components will be placed in the ink cartridge, the The ink storage space is affected, but is different from the conventional technology in that the present invention only needs to set the ink collection tank in the ink cartridge, so it does not affect the ink storage space of the ink cartridge.

Page 10 579333 V. Description of the invention (8) 4. Increasing ink replenishment efficiency: The shape of the ink collecting tank of the present invention can be radial, so it can increase the ink replenishing efficiency and reduce the probability of air bubble clogging, but even if it is not this shape In the ink collecting tank, the present invention can also quickly replenish the ink attached to the ink collecting tank to the air supply hole. 5. Prevent the gas from entering the ink tank and adjust the proper negative pressure inside the ink tank: When the ink tank is inverted (or tilted), the liquid-air interface formed by the air supply hole and the ink collection tank will prevent the gas from entering the ink tank from entering the tank improperly , So the proper negative pressure inside the ink cartridge cannot be adjusted.

The above are only the preferred embodiments of the present invention, and are not intended to limit the scope of implementation of the present invention; that is, all equivalent changes and modifications made in accordance with the scope of the patent application for the present invention are covered by the scope of the present invention .

579333 on page 11 Brief description of the drawing Figure 1 is a perspective view of the ink cartridge when it is upside down; Figure 2 is a sectional view of the ink cartridge when it is upside down in the direction of AA 'of Figure 1; Figure 3 A is the ink cartridge In the upright position, the cross-sectional view is taken in the direction of AA 'in FIG. 1; FIG. 3B shows the ink cartridge in the upright position, and the air bubbles enter the ink tank through the air supply hole, in the direction of A-A' in FIG. 1 Figure 4 is a three-dimensional cross-sectional view of the ink cartridge in the upright position and the air bubble enters the ink cartridge through the air supply hole, according to the direction of AA 'in Figure 1; When the shape of the ink tank is radial, the ink is back-filled to the three-dimensional cross-sectional view of the flow direction of the air supply hole through the ink collecting tank; Figure 6 is a structural diagram of the driving member disposed on the bottom surface of the ink collecting tank; A perspective sectional view of another embodiment of the groove. [Illustration of Symbols] Ink cartridge 1 Air supply hole .10 Backfill angle 11 Ink tank 20 Attachment angle 21 Driver 22 Bubble 30

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Claims (1)

579333 6. Scope of patent application 1. A liquid-gas interface maintaining device applied to an ink cartridge containing ink therein. The device includes: a gas-filling hole provided in the ink cartridge, and using a capillary phenomenon Ink is filled here; and an ink collection tank is disposed in the ink tank, communicates with the air supply hole, the ink tank and the air outside the ink tank, and the ink attached to the ink collection tank and the air supply hole are formed together. The liquid-gas interface prevents the air outside the ink cartridge from improperly entering the ink cartridge to adjust the proper negative pressure inside the ink cartridge. 2. The liquid-gas interface maintaining device according to item 1 of the scope of the patent application, wherein the surface of the ink collection tank is a surface that is easy to wet (we 11 ing) to increase the adhesion of the ink and adhere to the ink collection Groove surface. 3. The liquid-gas interface maintaining device according to item 2 of the scope of the patent application, wherein the surface that is easy to wet (we 11 in ng) is a rough surface. 4. The liquid-gas interface maintaining device according to item 2 of the scope of the patent application, wherein the surface that is easy to wet (we e 11 i n g) is coated with a hydrophilic agent. 5. The liquid-gas interface maintenance device according to item 2 of the scope of patent application, wherein the material of the ink collecting tank is a hydrophilic material. 6. The liquid-gas interface maintaining device according to item 1 of the scope of the patent application, wherein the ink collecting tank has a driving member adjacent to the air supply hole, so that gas in the form of a bubble enters the ink through the air supply hole. Keep the box away from the air supply hole. 7. The liquid-gas interface maintaining device according to item 6 of the scope of patent application, wherein the driving member is disposed on the bottom surface of the ink collecting tank. 579333 6. Scope of patent application 8. The liquid-gas interface maintenance device according to item 7 of the scope of patent application, wherein the driving member is a bump. 9. The liquid-gas interface maintaining device according to item 7 in the scope of the patent application, wherein the driving member is a sharp point. 10. The liquid-gas interface maintaining device according to item 6 of the scope of the patent application, wherein the driving member is disposed at an edge of the ink collecting tank. 11. The liquid-gas interface maintaining device according to item 10 of the scope of patent application, wherein the driving member is a bump. 1 2. The liquid-gas interface maintaining device according to item 10 of the scope of the patent application, wherein the dislodging member is a puppet point. 13. The liquid-gas interface maintaining device according to item 1 of the scope of the patent application, wherein the ink collecting tank has an attachment angle at an edge end, and the angle of the attachment angle is smaller than the flat angle for the ink to adhere. 1 4. The liquid-gas interface maintaining device according to item 1 of the scope of the patent application, wherein the bottom surface of the ink collecting tank is an solitary surface located on the opposite side of the ink collecting tank facing the ink tank from the position adjacent to the air supply hole . 15. The liquid-gas interface maintenance device according to item 1 of the scope of the patent application, wherein the air-filling hole has a backfill included angle at an edge end, and the angle of the back-filling included angle is smaller than a flat angle, so that gas in the form of a bubble enters through the air-filling hole After the ink cartridge, the ink is backfilled to the air supply hole. 16. The liquid-gas interface maintaining device according to item 1 of the scope of patent application, wherein the shape of the ink collection tank is convex polygonal. 17. The liquid-gas interface maintaining device according to item 16 of the scope of patent application, wherein the length-width ratio of the ink collection tank is greater than 1. 579333 6. Scope of patent application 1 8. The liquid-gas interface maintenance device as described in item 1 of the scope of patent application, wherein the air supply hole is located in the center of the ink collecting tank, and the distance from the edge is greater than 1/3 to 2/3 of the boundary length. between. 19. The liquid-gas interface maintaining device according to item 1 of the scope of the patent application, wherein the air-supply hole is located at the center of the ink collecting tank, and the distance from the edge is greater than 1/5 to 4/5 of the boundary length. Page 15