JPH11138843A - Ink cartridge for ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely detect an ink-out state by a comparatively simple structure. SOLUTION: A metallic ball 6 which is made of a conductive and light metallic material having a specific gravity smaller than ink 5 is inserted into a housing 1 of an ink cartridge. Two conductive bodies 10, 11 are provided to an upper section of a print head 2 at side of a bottom face of the housing 1 where the metallic ball 6 can be contacted thereto. Electrode plates respectively connected to the conductive bodies 10, 11 are provided to a side face of the housing 1 of the ink cartridge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink cartridge for an ink jet printer which is used by being mounted on an ink jet printer and which is filled with ink for printing by the ink jet printer.

[0002]

2. Description of the Related Art Ink jet printers are used with an ink cartridge filled with ink. When the ink in the ink cartridge runs out, printing failure occurs. , It is necessary to notify the user of the ink shortage. FIG. 6 is a perspective view showing a configuration of a conventional ink cartridge. As shown in the figure, a see-through window 31 is provided on the front surface of the ink cartridge housing 1. The see-through window 31 is formed by configuring a part of the ink cartridge housing 1 with a translucent material. A print head 2 is provided on the bottom side of the ink cartridge housing 1. Then, the user checks the state of the inside of the ink cartridge housing 1 seen through the see-through window 31 to grasp the remaining ink amount.

However, since the ink cartridge is usually mounted inside the printer, the ink cartridge is
In such a case, it is necessary to check the remaining ink amount by opening the door of the printer or removing the ink cartridge from the printer. Such a thing is troublesome for the user, and the user may neglect the operation. Therefore, there is a possibility that the ink may run out before the user notices and a printing failure may occur.

FIG. 7 is a sectional view showing the structure of an ink cartridge described in Japanese Patent Application Laid-Open No. 8-290579. As shown in the drawing, a float 42 made of synthetic resin or rubber having a specific gravity smaller than that of the ink 5 is inserted into the ink cartridge housing 4. Further, two electrodes 43 are provided in the ink supply port 41 on the bottom side of the ink cartridge housing 4. Further, the surface of the float 42 is processed so that the float 42 has conductivity. When the remaining amount of the ink becomes small, the surface of the float 42 comes into contact with the two electrodes 43, so that the two electrodes 43 are electrically connected, and the current flowing between them is used to indicate the ink end state by a lamp. According to such a configuration, the ink end state is automatically detected.

[0005]

Since the conventional ink cartridge for an ink jet printer is configured as described above, in order to enable detection of the ink end state, a conductor is attached to the surface of the float 42 or the like. A conductive process must be performed so that the float 42 has conductivity, such as to adhere conductive particles over a wide area, and a plurality of steps are required to form the float 42. Therefore, there is a problem that the cost of the ink cartridge increases.

The present invention has been made to solve such a problem, and an ink jet printer capable of detecting an ink end state with a relatively simple configuration and further reliably detecting the ink end state. An object of the present invention is to provide an ink cartridge.

[0007]

The ink cartridge for an ink jet printer according to the present invention has a lower portion formed in a funnel shape toward the bottom surface, a conductor provided on the bottom surface, and a metal sphere having a specific gravity smaller than that of the ink. It is of a configuration installed inside. Here, the metal sphere may be hollow. Further, the conductor provided on the bottom surface may be formed as a band-shaped region. An electrode plate connected to the conductor may be formed on the outer side surface of the cartridge.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the configuration of an ink cartridge for an ink jet printer according to the present invention. FIG. 2 is a sectional view showing a section of the ink cartridge for an ink jet printer shown in FIG.
As shown in FIGS. 1 and 2, a metal ball 6 made of a conductive light metal having a specific gravity smaller than that of the ink 5 is inserted into the ink cartridge housing 1. In addition, two conductors 10 and 11 are provided at a position where the metal ball 6 can contact with the upper part of the print head 2 on the bottom surface side of the ink cartridge housing 1. On the side of the ink cartridge housing 1,
An electrode plate 3 connected to each of the conductors 10 and 11 is provided.

If it is difficult to select a metal sphere 6 having a specific gravity smaller than the specific gravity of the ink 5, the metal sphere 6 may be hollow. The shape of the metal sphere 6 may be spherical or elliptical spherical. As shown in FIG. 1, the shape of the ink cartridge housing 1 in this embodiment has a funnel shape at the bottom. That is, the cartridge has a shape in which the inner diameter of the cartridge is reduced from a predetermined position below the ink cartridge housing 1 toward the print head 2. And conductor 1
Reference numerals 0 and 11 are formed at the lowest portion inside the ink cartridge housing 1.

Next, a method of detecting an ink end state in the ink cartridge for an ink jet printer shown in FIGS. 1 and 2 will be described. As the ink 5 is consumed and decreases, the liquid level of the ink 5 drops. Along with this, the position of the metal sphere 6 floating on the surface of the ink 5 goes down. Then, when the liquid level of the ink 5 drops to the position of the bottom surface of the ink cartridge housing 1, the metal sphere 6
Contact 0,11. Then, since the conductors 10 and 11 conduct, a current flows between them. If the flow is detected, the ink end state can be detected. If the ink end state is detected, information indicating the ink end state can be output to the user.

In this embodiment, the lower part of the ink cartridge housing 1 is funnel-shaped, in other words,
Since the inner wall surface of the cartridge at the lower portion of the ink cartridge housing 1 has a slope shape, the metal sphere 6 surely descends toward the print head 2. Therefore, when the ink end state actually occurs, the metal ball 6
Is reliably in contact with the conductors 10 and 11, so that the ink end state is reliably detected.

As shown in FIG. 3, the bottom surface of the ink cartridge housing 1 is flat, and a concave portion is formed in a part of the flat surface so that the metal ball 6 fits therein. If the configuration is such that the ink end state is detected when the metal ball 6 fits into the recess, the metal ball 6 fits into the recess when the ink end state actually occurs. First (Fig. 3
, The situation where the ink end state cannot be detected may occur.

As shown in FIG. 4, the conductors 10 and 11 may be formed in a relatively long strip shape. Then, since the area of the conductors 10 and 11 increases, when the metal ball 6 reaches the position of the conductors 10 and 11, the metal ball 6 and the conductor 1
The range of contact between the conductors 0 and 11 is increased, and conduction between the conductors 10 and 11 is more reliably ensured. That is, the detection of the ink end state is reliably performed.

The printer is used by being connected to a host such as a personal computer. When the host and the printer are connected by a bidirectional printer cable or LAN, the connection between the metal ball 6 and the conductors 10 and 11 is established. An electric signal generated based on the contact can be transmitted to the host. The host can, for example, display a message on a monitor based on the electrical signal. FIG. 5 is a flowchart showing such an operation. An electrode plate 3 connected to the conductors 10 and 11 is provided on a side surface outside the ink cartridge housing 1. A conductor that is in contact with the electrode plate 5 when the ink cartridge is mounted on the printer is provided in the ink cartridge mounting space of the printer. Therefore, when the ink cartridge is mounted on the printer, the conductors 10 and 11 are easily electrically connected to the printer main body via the metal plate 3 and the conductor on the printer main body side.

As shown in FIG. 5, when the metal ball 6 reaches the bottom of the ink cartridge housing 1 (step S
1) As described above, an electric signal is generated based on the contact between the metal ball 6 and the conductors 10 and 11 (step S).
3). Then, the signal is sent to the host via the printer main body and the bidirectional printer cable or LAN (step S3). When receiving the signal, the host displays a message of "no ink remaining" on the monitor (step S4). According to the message, the user can replace the ink cartridge (step S5). If the metal ball 6 has not reached the bottom surface of the ink cartridge housing 1 (step S1), no electric signal is generated, so that the printing process is continued (step S2).

[0016]

As described above, according to the present invention, an ink cartridge for an ink jet printer has a lower portion formed in a funnel shape toward the bottom surface, a conductor provided on the bottom surface, and a metal having a specific gravity smaller than that of the ink. Since the sphere is set inside, there is no need to perform a special conductive process on the object floating on the ink, and the ink end state can be detected with a relatively simple configuration. Further, since the metal sphere descends along the funnel-like shape, the metal sphere can be surely descended toward the conductor, and there is an effect that the ink end state can be more reliably detected. When the metal sphere is formed of a hollow material, a material having a relatively large specific gravity can be selected, and there is an effect that the restriction on the material of the metal sphere can be relaxed. When the conductor provided on the bottom surface is formed as a band-like region, the contact area between the metal ball and the conductor when the metal ball reaches the position of the conductor is increased, and the conductor is more reliably formed. Thus, there is an effect that the conduction between them is ensured, and the detection of the ink end state is reliably performed. When an electrode plate connected to a conductor is formed on the outer side surface, there is an effect that electric signals can be easily exchanged between the printer main body and the ink cartridge.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a configuration of an ink cartridge for an inkjet printer according to the present invention.

FIG. 2 is a sectional view showing a section of the ink cartridge for an ink jet printer shown in FIG. 1;

FIG. 3 is a cross-sectional view for explaining the superiority of the ink cartridge for an ink jet printer according to the present invention.

FIG. 4 is an explanatory view showing one form of a bottom surface of an ink cartridge for an ink jet printer.

FIG. 5 is a flowchart showing a process for displaying a message on a host such as a personal computer.

FIG. 6 is a perspective view showing a conventional ink cartridge for an ink jet printer.

FIG. 7 is a sectional view showing another conventional ink cartridge for an ink jet printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink cartridge housing 2 Print head 3 Metal plate 5 Ink 6 Metal ball 10, 11 Conductor

Claims (4)

[Claims] An ink cartridge for an ink jet printer filled with ink for printing by an ink jet printer, wherein a lower portion is formed in a funnel shape toward a bottom surface, a conductor is provided on the bottom surface, and An ink cartridge for an ink jet printer, comprising a metal sphere having a specific gravity smaller than that of the ink. 2. The ink cartridge according to claim 1, wherein the metal sphere is hollow. 3. The ink cartridge for an ink jet printer according to claim 1, wherein the conductor is formed as a band-shaped region. 4. The ink cartridge for an ink jet printer according to claim 1, wherein an electrode plate connected to the conductor is formed on an outer side surface.