WO2012034500A1

WO2012034500A1 - Backpressure ink catridge

Info

Publication number: WO2012034500A1
Application number: PCT/CN2011/079503
Authority: WO
Inventors: 李世强; 王铖
Original assignee: 珠海天威飞马打印耗材有限公司
Priority date: 2010-09-13
Filing date: 2011-09-09
Publication date: 2012-03-22
Also published as: CN201776988U

Abstract

Disclosed is a backpressure ink catridge comprising a catridge body (1, 2) which has an ink storage chamber (7, 10), an ink supply port (8) and an air-guiding buffer chamber (4). The air-guiding buffer chamber (4) is in communication with the atmosphere via an air inlet (3), and the bottom of the air-guiding buffer chamber (4) is in communication with the ink storage chamber (7, 10) via an air-guiding passage (5). A hollow column (6) having an inner cavity (61) is provided on the bottom of the ink storage chamber (7, 10), with the top part of the inner cavity (61) being in communication with the ink storage chamber (7, 10) and the bottom of the inner cavity (61) being in communication with the air-guiding passage (5).

Description

Back pressure type ink cartridge

Technical field

The present invention relates to an ink cartridge for an ink jet printer, and more particularly to a back pressure type ink cartridge. The present application claims priority to Chinese Patent Application No. 2010.

Background technique

An inkjet printer is a commonly used printer. The printing method is usually to provide an ink source by an ink device such as an ink cartridge, and the ink is transported to the recording head through a corresponding ink flow pipe, and the ink is driven by the printing signal. The nozzles provided on the recording head are ejected onto a recording medium such as paper to perform recording of characters or figures.

Existing ink cartridges for ink jet printers include a back pressure chamber for storing ink, an air inlet for maintaining air pressure balance with an external environment, an ink supply port for supplying ink to the print head of the printer, and a vacuum mechanism. The negative pressure mechanism is a mechanism for ensuring the ink in the ink cartridge to be in a certain negative pressure state in order to ensure the normal ink supply and the storage requirement of the ink. The negative pressure mechanism usually adopts a sponge body built in the back pressure chamber, and the sponge body is built in. The capillary effect keeps the ink; because the built-in sponge is filled with the back pressure chamber and the adsorption characteristics, the printer can not completely absorb the ink in the sponge. After the ink cartridge is used up, a large amount of ink remains in the sponge, and the larger the volume of the sponge, the ink The more the residual amount, the more ink remains in the sponge, which wastes and increases the user's cost of use. In addition, some ink cartridges use a valve as a negative pressure mechanism to control the flow of ink through the opening of the valve. When the printer is operating, the valve opens and ink begins to feed the printhead. When printing is stopped, the valve is closed and the ink is stopped. The ink cartridge with the valve as the negative pressure mechanism has a complicated structure, which also increases the manufacturing cost.

Chinese utility model patent 03207733.5 discloses a back pressure type ink cartridge which is internally provided with an air passage, the upper end of which is connected to the atmosphere as an air inlet of the ink cartridge, and the lower end is at the bottom of the back pressure chamber of the ink cartridge. When the printer is working, the ink in the back pressure chamber is pumped away, and a certain amount of negative pressure is formed in the ink cartridge. The air then enters the inside of the ink cartridge from the outside through the end of the air passage, because the other end of the air passage is immersed in the ink, and At the bottom of the back pressure chamber, the air must overcome a certain water pressure to enter, resulting in the volume of air replenished into the back pressure chamber, which is always smaller than the volume of ink drawn by the printer, so that the inside of the ink cartridge is always under negative pressure.

In addition, some ink devices designed by the principle of back pressure structure are provided with a plurality of buffer chambers in the air guiding passage portion thereof, and the air guiding passages communicate with the ink chamber through the bottom of the buffer chamber. The outside atmosphere passes through the air guiding passage and the buffer chamber, and finally enters the ink chamber from the bottom position of the ink device, providing the pressure supplement required for printing.

The ink device designed by the principle of back pressure structure cannot be designed too large due to the limitation of the volume of the ink device and the requirement of the ink capacity. As the ink in the ink unit is gradually consumed, the portion of the gas contained in the ink chamber gradually increases. In this case, when the ambient temperature has a large variation range, according to the gas balance equation: PT/V = constant, the gas in the ink chamber will contract and expand as the ambient temperature difference changes. Because of the ink device designed by the back pressure structure, the outside atmosphere is entered into the ink chamber by the air guiding channel through the bottom of the buffer chamber. Under this condition, when the gas in the ink chamber expands due to an increase in the ambient temperature, the ink in the ink chamber is squeezed into the buffer chamber of the ink device. Since the buffer chamber volume of the ink device cannot be designed to be large enough, when more ink is squeezed into the buffer chamber, a part of the ink may overflow from the air inlet.

technical problem

The technical problem to be solved by the present invention is to provide an improved back pressure type ink cartridge for improving the problem that ink in the ink chamber overflows from the air inlet due to a change in the temperature difference of the external environment.

Technical solution

In order to solve the above technical problem, the present invention adopts the following technical solution: a back pressure type ink cartridge is provided, comprising: a box body having an ink storage chamber, an ink supply port and a gas guiding buffer chamber; and the air guiding buffer The cavity is connected to the atmosphere through the air inlet, the bottom of the air guiding buffer is communicated with the ink storage chamber through a gas guiding passage; the bottom of the ink storage chamber is provided with a hollow column having a cavity, the inner cavity The top of the chamber is in communication with the ink reservoir, and the bottom of the chamber is in communication with the air passage.

Preferably, the air guiding channel is located at the bottom of the casing.

Preferably, a porous material member is disposed in the air guiding buffer chamber.

Preferably, the air inlet is located at the top of the air guiding buffer chamber.

Preferably, the ink storage chamber comprises a back pressure chamber and an ink supply chamber separated by a partition, and the back pressure chamber is connected to the ink supply chamber through a passage of the bottom of the partition, the hollow column is located at the The bottom of the back pressure chamber is located at the bottom of the ink supply chamber. The back pressure chamber is divided into an upper cavity and a lower cavity by a plane of a top surface of the hollow column, and a volume of the air guiding buffer cavity is not less than 1.7% of a volume of the upper cavity.

Beneficial effect

The ink cartridge of the present invention can effectively prevent the occurrence of a problem that ink overflows from the air inlet by increasing the hollow column of a certain height at the bottom position of the ink storage chamber.

DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view showing the appearance of an embodiment of a back pressure type ink cartridge of the present invention.

Figure 2 is a cross-sectional view of the casing of the back pressure type ink cartridge shown in Figure 1.

Fig. 3 is a view showing a state of ink supply when the ink in the back pressure type ink cartridge shown in Fig. 1 is at a high capacity.

4 is a schematic view showing changes in ink level in the back pressure chamber and the air guiding buffer chamber when the ambient temperature is increased in the back pressure type ink cartridge shown in FIG. 3.

Fig. 5 is a view showing a state of ink supply when the ink in the back pressure type ink cartridge shown in Fig. 1 is at a medium capacity.

FIG. 6 is a schematic view showing the change of the ink level in the back pressure chamber and the air guiding buffer chamber when the ambient temperature is increased in the back pressure type ink cartridge shown in FIG. 5. FIG.

Fig. 7 is a view showing a state of ink supply when the ink in the back pressure type ink cartridge shown in Fig. 1 is at a low capacity.

FIG. 8 is a schematic view showing changes in ink level in the back pressure chamber and the air guiding buffer chamber when the ambient temperature is increased in the back pressure type ink cartridge shown in FIG. 7. FIG.

Embodiments of the invention

The invention is further described below in conjunction with the drawings and specific embodiments.

Referring to FIG. 1 and FIG. 2, a back pressure type ink cartridge of the present invention comprises a box body composed of a bottom case 1 and a top cover 2, and the bottom case 1 has a gas guiding buffer chamber 4, a gas guiding passage 5, and a hollow column. 6. The back pressure chamber 7, the ink supply chamber 10, the ink supply port 8, and the like, and the air guiding buffer chamber 4 is provided with a porous material member 12 such as a sponge for holding the negative pressure inside the box. The hollow column 6 has an inner cavity 61. The air inlet 3 and the ink filling port 9 of the ink cartridge are formed on the top cover 2, the hollow column 6 is located at the bottom of the back pressure chamber 7, and the air guiding passage 5 is located at the bottom of the casing. Wherein, the ink supply port 8 is located at the bottom of the ink supply chamber 10 and communicates therewith, and the back pressure chamber 7 and the ink supply chamber 10 are separated by the partition 11 and communicated through the passage at the bottom of the partition plate 11, the air guiding buffer chamber 4 The top portion communicates with the atmosphere through the air inlet 3, and the bottom of the air guiding buffer chamber 4 communicates with the inner cavity 61 of the hollow column 6 through the air guiding passage 5, and the top of the inner cavity 61 communicates with the back pressure chamber 7, which The bottom of the inner chamber 61 communicates with the air guiding passage 5.

During the printing process of the ink jet printer, the ink in the back pressure chamber 7 and the ink supply chamber 10 is supplied to the printer recording head via the ink supply port 8, and the outside atmosphere passes through the air guiding buffer chamber 4 and the air guiding passage 5 via the air inlet 3. The inner cavity 61 of the hollow column 6 enters the back pressure chamber 7 to maintain the pressure balance in the back pressure chamber 7 when the ink is consumed. Since the air guiding passage 5 is designed at the bottom of the ink cartridge, even when the ink in the back pressure chamber 7 is gradually depleted due to continuous consumption, the stability of the pressure supplied to the back pressure chamber 7 by the outside atmosphere can be ensured.

When the printer is in an inoperative state, the ink cartridge placed in the printer's character car will expand as the ambient temperature rises as the ambient temperature changes (rises or lowers). Shrinks as the ambient temperature decreases.

3, 5, and 7 are cross-sectional views of the ink in the back pressure chamber 7 at a high capacity, a medium capacity, and a low capacity, respectively. When the ambient temperature rises, the gas in the back pressure chamber 7 will expand. According to the gas balance equation PV/T=constant, the expansion volume of the gas is ΔV=ΔT/T*V, where T and V are the initial ambient temperature and the volume of the gas in the back pressure chamber 7, respectively, ΔT is the environment. The degree of temperature change. It can be seen that under the same initial ambient temperature T and the same ambient temperature change ΔT, the gas expansion volume ΔV is proportional to the V of the gas in the back pressure chamber 7 in the initial state. That is, under the same ambient temperature change condition, as the ink in the back pressure chamber 7 is gradually consumed, the gas volume V in the back pressure chamber 7 gradually increases, and the gas expansion volume ΔV also gradually increases. 4, FIG. 6, and FIG. 8 respectively correspond to the gas expansion and the change of the ink level in the back pressure chamber 7 when the temperature of the external environment is increased in the ink cartridges of FIG. 3, FIG. 5, and FIG.

In the conventional back pressure structure ink cartridge, the volume of the air guide buffer chamber 4 of the ink cartridge cannot be designed too large due to the limitation of the outer shape size of the ink cartridge and the minimum ink amount of the canned ink cartridge. In the case where less ink remains in the back pressure chamber 7 (i.e., the gas V in the back pressure chamber 7 is large in the initial state), when the ambient temperature is greatly increased (that is, the ambient temperature change ΔT is also large) Because the gas volume in the back pressure chamber 7 is greatly expanded and the volume of the air guiding buffer chamber 4 of the ink cartridge is too small, the ink in the back pressure chamber 7 is filled with the air guiding buffer chamber 4 and further from the air inlet. 3 Poor phenomenon of overflow.

By adding a hollow column 6 of a certain height to the bottom of the back pressure chamber 7, it is possible to effectively prevent the ink from overflowing from the air inlet. As shown in Fig. 4 and Fig. 6, at this time, there are many residual inks in the back pressure chamber 7, and there is little gas in the back pressure chamber 7, even when the ambient temperature change ΔT is large, the change of ΔV is very high. Small, there is no problem that the ink fills the air guiding buffer chamber 4 and further overflows from the air inlet 3. In the case where the amount of ink remaining in the back pressure chamber 7 shown in FIG. 8 is small, when the environmental temperature change ΔT is large, although the change of ΔV is large, the ink in the back pressure chamber 7 at this time is large. The liquid level is already lower than the height of the hollow column 6, so that the increased gas volume ΔV in the back pressure chamber 7 can be directly discharged through the hollow column 6 and from the air inlet 3 without the ink in the back pressure chamber 7. discharge.

In actual use, the change of ambient temperature is generally not less than 5 ° C, in the case of △ T = 5 ° C, △ V = △ T / T * V = 5 / (273 + 25) * V = 1.7%*V. The volume of the air guiding buffer chamber 4 is set to V', and the back pressure chamber 7 is divided into the upper chamber V1 and the lower chamber V2 by the plane of the top surface of the hollow column 6, as long as V'≥1.7%*V1 is ensured. The ink is completely prevented from overflowing from the air inlet.

Industrial applicability

The ink cartridge of the present invention increases the hollow column having a certain height at the bottom position of the ink storage chamber, and can effectively prevent the occurrence of the problem that the ink overflows from the air inlet.

Claims

A back pressure type ink cartridge comprising:

a box body having an ink storage chamber, an ink supply port and a gas guiding buffer chamber;

The air guiding buffer chamber communicates with the atmosphere through the air inlet, and the bottom of the air guiding buffer chamber communicates with the ink storage chamber through the air guiding passage;

It is characterized by:

The bottom of the ink storage chamber is provided with a hollow column having a cavity, and a top of the inner cavity is in communication with the ink storage chamber, and a bottom of the inner cavity is in communication with the air guiding channel.
The back pressure type ink cartridge according to claim 1, wherein said air guiding passage is located at a bottom of said casing.
The back pressure type ink cartridge according to claim 1, wherein a porous material member is provided in the air guiding buffer chamber.
The back pressure type ink cartridge according to claim 1, wherein said air inlet is located at a top of said air guiding buffer chamber.
The back pressure type ink cartridge according to claim 1, wherein the ink storage chamber comprises a back pressure chamber and an ink supply chamber separated by a partition, and the back pressure chamber passes through a passage of the bottom of the partition The ink supply chambers are connected, the hollow columns are located at the bottom of the back pressure chamber, and the ink supply ports are located at the bottom of the ink supply chamber.
The back pressure type ink cartridge according to claim 5, wherein the back pressure chamber is divided into an upper cavity and a lower cavity by a plane of a top surface of the hollow column, and a volume of the air guiding buffer cavity is not less than The upper chamber volume is 1.7%.