CN2400277Y - Pressure regulating mechanism - Google Patents

Abstract

The utility model discloses a pressure adjustment mechanism in the ink supply card casket of printer, only dispose an elastic air bag in the ink tank, and this air bag inside and the circulation of each other of the outside air of ink supply card casket. When the pressure difference between the air pressure in the air bag and the back pressure of the ink tank is changed, the elastic air bag can automatically regulate the volume of the air bag to expand or contract due to the elastic structure of the elastic air bag, so that the volume of the ink tank is changed, unnecessary ink leakage of the ink tank can be prevented, and the printing head can smoothly eject ink drops.

Description

pressure regulator

The utility model relates to a printer, in particular to a pressure regulating mechanism for regulating pressure changes in an ink tank of an ink supply cartridge.

In the era of information explosion and widespread use of computers, not only the use of computers themselves has surged, but their quality and processing speed are also subject to strict requirements. In addition, all peripheral devices that cooperate with computers are also affected by this trend; not only are various peripheral devices constantly being introduced, but their functions and quality are also improving day by day. Among all common computer peripheral equipment, the most common one is a printer, and it has gradually become an indispensable output equipment for all computer users.

From the perspective of the evolution of printers on the market, printers can be divided into three types according to their printing methods: dot matrix printers, inkjet printers, and laser printers. Dot-matrix printers, while inexpensive, are too slow and of poor quality to compete with inkjet or laser printers in the market place, and are currently used only for specific purposes. Most of the inkjet printers or laser printers are used in the market now, and both have their own advantages in comparison. Among them, the price of inkjet printers is relatively low, while the price of laser printers is relatively high. This is the advantage of inkjet printers; , The printing quality of inkjet printers is poor, while the printing quality of laser printers is better, which is the advantage of laser printers.

Although inkjet printers have a price advantage over laser printers, their poor print quality and slow print speed tend to make them less competitive in advanced applications. Generally speaking, inkjet printers use fluid (ink) as the printing material, and the physical phenomena of the fluid cause poor printing quality, such as: the shape of the ink is not fixed, the flow is not smooth, the ink contains air bubbles, and the fluid is sticky. The coefficient is too small so that the ink flow direction is not easy to control.

The art of inkjet printing generally involves mechanisms that control the release of ink droplets from the ink reservoirs to the printing surface. As described in the known technology, the inkjet printing method utilizes an inkjet head (Print Head) configured on the ink cartridge, and ejects ink droplets in response to a control signal.

Inkjet heads generally have two ways of ejecting ink droplets: thermal bubble type and piezoelectric type. The thermal bubble type inkjet head uses a thin film resistor to heat to rapidly vaporize a small part of the ink (that is, ink droplets) through Nozzle sprays out.

Another type of piezoelectric inkjet head uses piezoelectric elements to respond to control signals, compressing the volume of ink to generate pressure waves that force ink droplets to be ejected through nozzle holes.

Although the two inkjet printing methods of the known technology can effectively eject ink droplets from the ink tank, they cannot prevent the ink from leaking from the inkjet head when there is no printing. Therefore, the known technology still needs a technology that can keep the ink from leaking when the print head is not printing, and this purpose can be achieved by providing a slight back pressure (Slight Back Pressure) in the ink tank. . The back pressure mentioned here refers to the formation of a partial vacuum state in the ink tank or the pressure in the ink tank which is lower than the atmospheric pressure, so as to prevent the ink from flowing freely through the inkjet head. In addition, increasing the back pressure means increasing the difference between the pressure in the ink tank and the atmospheric pressure.

The back pressure in the ink supply cartridge must be able to prevent the ink from leaking out at any time, and the back pressure must not be too high, so that the ink cannot overcome the back pressure and cannot be ejected. In addition, the ink supply cartridge must be designed to maintain operation under any environmental changes. Therefore, the back pressure in the ink tank must be maintained for good operation. That is, when the inkjet head is not in operation, the ink can be kept from leaking out, and at the same time, the ink ejection will not be affected when the inkjet head is in the printing state. If the liquid level decreases due to ink consumption, the back pressure in the ink tank will therefore decrease as the volume increases according to the ideal gas formula. If the aforementioned increased back pressure is not properly adjusted, the ink head will not be able to overcome the increased back pressure in the subsequent work and will not be able to eject ink droplets.

As pointed out in U.S. Patent No. 5,409,134, a pressure adjustment mechanism has an air bag and a shrapnel that can act as the back pressure in the ink tank changes. The pressure adjustment mechanism can move between the minimum volume position and the maximum volume position. . This pressure adjustment mechanism can change the gas of the ink tank air to adjust the back pressure change, so that the back pressure in the ink tank can be maintained within a working range so that the ink does not leak when it is not in use and when the inkjet head is heated Ink droplets are ejected smoothly.

For example, when the ambient air pressure drops and the pressure difference between the atmospheric pressure and the back pressure decreases, the pressure adjustment mechanism will increase the volume of the ink tank to increase the back pressure to keep the ink from leaking out.

The pressure adjusting mechanism disclosed in the above-mentioned U.S. patent includes a pair of elastic sheets 6 on which an inelastic but inflatable air bag 20 is attached. The shrapnel 6 and the air bag 20 are arranged in the ink tank 3 of the ink supply cartridge, and the inside of the air bag 20 is in air circulation with the outside of the ink supply cartridge, as shown in FIG. 1 . The cooperating use of the shrapnel 6 and the air bag 20 enables the air bag 20 to expand and contract with the pressure. Change and act.

Please refer to FIG. 2 , the expansion of the air bag 20 will cause the elastic sheet 6 to deviate to generate elastic force, and the elastic sheet will force the air bag to shrink, so the cooperation between the elastic sheet 6 and the air bag 20 will maintain a balanced state. The balance state of expansion and contraction of the air bag affects the volume of the ink tank 3, and thereby adjusts the back pressure of the ink tank 3 within the normal operating range, so that the ink supply cartridge can be used as usual without being affected by changes in external air pressure or ink consumption Work.

However, the pressure regulating mechanism formed by combining the shrapnel 6 and the air bag 20 attached to it must accurately grasp the elastic coefficient of the shrapnel 6 and the expansion and contraction performance of the air bag 20 in the manufacturing technology, so as to obtain satisfactory function. If the degree of adhesion between the shrapnel 6 and the air bag 20 is not good, it will cause the two to separate, and it may also make the pressure regulating mechanism's ability to detect pressure changes worse. Due to the relatively strict requirements on the physical properties of the shrapnel 6 and the air bag 20 in the manufacturing technology, the qualified rate of product production is relatively reduced. Therefore, the utility model provides a method that can effectively control its quality in manufacturing compared with the known technology, and Simplify the complexity of the mechanism with fewer parts to improve the qualified rate, making the utility model more practical.

Therefore, the purpose of this utility model is to provide a pressure regulating mechanism with a high pass rate and a simpler structure in view of the shortcomings of the above-mentioned pressure regulating mechanism.

In order to achieve the above purpose, the utility model adopts the following technical solution: the pressure regulating mechanism includes:

a connection seat provided on the ink cartridge housing and having a through hole, and

An elastic air bag made of high molecular polymer material, one end of the elastic air bag is open and arranged inside the ink supply cartridge, the opening is tightly bound on the connecting seat and communicated with the outside air.

Because the pressure regulating mechanism of the utility model only configures a single elastic air bag in the ink supply cassette, and the inside of the air bag communicates with the air outside the ink supply cassette. When the pressure difference between the air pressure inside the air bag and the back pressure in the ink tank changes, the elastic air bag can adjust its own expansion or contraction by its own elasticity, so as to change the volume of the ink tank and maintain the back pressure within a certain range. In this way, it can prevent the ink tank ink from leaking in the unused state and keep the inkjet head to eject ink droplets smoothly.

Below in conjunction with accompanying drawing and preferred embodiment, the utility model is described in detail.

FIG. 1 is a schematic cross-sectional view of a known pressure regulating mechanism in an ink cartridge.

FIG. 2 is a schematic cross-sectional view of the pressure regulating mechanism in FIG. 1 deforming the shrapnel when the air bag expands.

Fig. 3 is a schematic cross-sectional view of the pressure regulating mechanism in the ink supply cartridge of the present invention.

Fig. 4 is a schematic cross-sectional view of the pressure regulating mechanism of the present invention when the elastic air bag is inflated.

Fig. 5 is a schematic cross-sectional view of a pressure regulating mechanism according to another embodiment of the present invention.

in the picture

1 Upper cover 2 Tank body

3 ink tanks 4 central perforation

5 seat body 6 shrapnel

10 Connecting seat 11 Through hole

20 air bags 21 neck

22 Elastic part 23 Elastic air bag

7 inks 30 elastic devices

31 hook structure

Firstly, please refer to FIG. 3 to illustrate a preferred embodiment of the present invention, wherein the ink supply cartridge is formed by combining an upper cover 1 and a tank body 2 . When the upper cover 1 is fixedly connected to the tank body 2, the inner space formed determines the capacity of the ink tank 3 of the ink supply cartridge and receives ink therein. An inkjet head (not shown) is arranged below the ink tank. The inkjet head has a plurality of openings and the ink in the ink tank 3 is expanded by heat or pressure by the aforementioned known heating method or piezoelectric method. Squeeze and spray.

Continuing to refer to FIG. 3 , the pressure adjustment mechanism of the present invention is mainly formed in the ink supply cassette, one end of which is connected to the upper cover 1 and the other end hangs inside the ink supply cassette. The pressure regulating mechanism includes a connecting seat 10 and an elastic air bag 23, wherein the elastic air bag 23 has a neck 21 and an elastic portion 22, the neck 21 is tightly bound under the connecting seat 10, and the connecting seat 10 has a through hole 11 And make the inside of the connected elastic air bag 23 circulate with the outside air, wherein the diameter of the through hole 11 is about 1-3mm±0.05mm.

The effect of aforementioned elastic airbag 23 is like an inflatable and shrinkable balloon, as shown in Figure 3, in this elastic airbag 23, it is hollow and can expand or contract due to changes in pressure, while its opposite outside is The ink in the ink cartridge and its space contact. The elastic air bag 23 can be made of high molecular polymer, such as: latex, silica gel, rubber, and the material of the air bag has a non-linear elastic coefficient, and the yield strength is between 5600-6400 kg/cm ² .

Please refer to Fig. 3 again, the upper cover 1 of the ink supply cartridge is provided with a central perforation 4 for accommodating the connecting seat 10 of the pressure regulating mechanism, and the connecting seat 10 is tightly fitted on the upper cover 1, as mentioned above, The diameter of the through hole 11 is about 1 mm to 3 mm, which is much smaller than the diameter of the elastic air bag 23, so the inflation and deflation of the elastic air bag 23 will not reduce the adjustment function because it is too sensitive to the air volume and air pressure. Under normal use conditions, that is, the ink supply cartridge has been opened and installed in the inkjet printer, if the external environment changes (for example: the working temperature rises or the working atmospheric pressure is less than atmospheric pressure) and the back pressure in the ink supply cartridge is greater than Atmospheric pressure, the elastic part 22 of the elastic air bag 23 will compress the volume inside the front elastic air bag 23 and discharge the air through the through hole 11 due to the reduced pressure difference, thereby reducing the liquid level of the ink and maintaining the ink supply cartridge The pressure is balanced, and therefore there is no ink leakage.

Next, please refer to FIG. 4 , which illustrates a cross-sectional view of the elastic air bag 23 of the pressure regulating mechanism of the present invention when it is inflated. With the continuous printing operation of the inkjet head, the ink in the ink tank 3 is gradually reduced and the liquid level is lowered. According to the ideal gas formula, it can be known that the back pressure in the ink tank 3 will decrease when the volume of the sealed ink supply cartridge increases. Therefore, the pressure (atmospheric pressure) in the aforementioned elastic air bag 23 will be greater than the back pressure in the ink tank 3 so that the elastic portion 22 will be properly inflated and inflated, as shown in FIG. 4 . The aforementioned expanded volume will further raise the descending ink liquid level to return to the initial equilibrium state. Through the pressure regulating mechanism of the present invention, the ink supply cartridge can maintain a specific pressure balance in any state to ensure smooth ink printing.

In order to make the pressure regulating mechanism of the present invention more sensitive to pressure changes, in another preferred embodiment of the present invention, an elastic device 30 will be installed outside the elastic air bag 23 . Please refer to shown in Figure 5, the parts of the pressure regulating mechanism in this embodiment are roughly the same as the foregoing, the difference is that an elastic device 30 is added, and one end of the elastic device 30 is fixed on the ink supply cartridge housing , the other end is connected to the elastic air bag 23. In the present utility model, one end of the elastic device 30 is fastened to the hook structure 31 arranged at the inner bottom of the tank body 2, while the other end is fixedly connected to the elastic air bag 23 to hang end. Such configuration, the elastic device 30 makes the elastic air bag 23 produce an elastic pulling force, so that when the utility model encounters changes in the atmospheric pressure of the external environment or changes in the back pressure in the ink tank 3, the elastic part 22 of the elastic air bag 23 can be more resilient. Immediately adapt to changes in pressure difference, moderate expansion or contraction. Of course, the hanging end of the elastic air bag 23 can also be directly fixed on the ink supply cartridge housing, that is, the bottom of the tank body 2, thereby providing a prestress for the elastic air bag 23, making it more sensitive when inflated .

The present invention is not limited to the above-mentioned embodiments. For example, the present invention does not limit the shape of the elastic air bag, as long as the shape can provide elasticity appropriately.

To sum up, according to the pressure regulating mechanism implemented by the utility model, the ink supply cartridge will not be affected by external pressure changes or ink consumption conditions to work normally, and the ink supply cartridge can be adjusted by a single elastic air bag The back pressure of the ink tank can effectively control the pass rate of the product.

Claims (3)

1. A pressure regulating mechanism, characterized in that, comprising: a connection seat provided on the ink cartridge housing and having a through hole, and An elastic air bag made of high molecular polymer material, one end of the elastic air bag is open and arranged inside the ink supply cartridge, the opening is tightly bound on the connecting seat and communicated with the outside air. 2. The pressure regulating mechanism according to claim 1, further comprising an elastic device, one end of which is fixed on the housing of the ink supply cartridge, and the other end is connected to the elastic air bag. 3. The pressure regulating mechanism according to claim 1, characterized in that: one end of the elastic air bag can also be directly fixed on the housing of the ink supply cartridge.

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