JPH01244862A - Ink cartridge with pressure type ink recovery system - Google Patents

Abstract

PURPOSE:To prevent non-fixing liquid from being refluxed to an ink tank side of the non-fixing liquid when the non-fixing liquid is replaced with recording ink, by a method wherein a check value is automatically opened and closed by utilizing a pressure difference between a liquid pressure in an ink passage part from a printing head to a liquid chamber of a pressurizing mechanism part and hydraulic pressure on the ink tank side. CONSTITUTION:When a pressure operation part 9 of a pressurizing mechanism part 7 is pressed, pressure in pressing of non-fixing liquid overcomes pressure action of atmospheric pressure or the like given to recording ink 2 during that time, and restrains a collar part 10a of a check valve 10. Therefore, the non-fixing liquid is prevented from being refluxed from the inside of said liquid chamber 8 to a tank side ink passage 5. Beside, when pressing on the pressure operating part 9 is stopped, liquid pressure of the non-fixing liquid existing from a printing head 7 to the liquid chamber 8 of the pressurizing mechanism part 7 decreases as a form of the pressure operation part 9 returns to an original state, and a pressure difference occurs between said liquid pressure and ink pressure in the tank side ink passage 5. Therefore, the check valve 10 is opened, and recording ink 2 in the tank passage 5 flows into the liquid chamber 8.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a head-integrated disposable ink cartridge for an inkjet printer, particularly an ink cartridge equipped with a pressurized ink recovery system.

[Prior Art] Some inkjet printers are known to use so-called head-integrated disposable ink cartridges (hereinafter also referred to as ink cartridges), and some inkjet printers also use ink cartridges equipped with a pressurized ink recovery system. It will be done.

This ink cartridge with pressurized ink recovery system has
Before use, to prevent the recording ink from sticking, fill the part on the print head side with non-stick liquid, and before use, drain this non-stick liquid and apply recording ink from the ink tank to that part. I'm trying to get an inflow.

In this case, a pressure mechanism is used to replace the non-stick liquid with recording ink, but in conventional ink cartridges, this pressure mechanism prevents the non-stick liquid from flowing back from the ink supply path toward the ink tank. A valve is provided to prevent backflow of the non-stick liquid when replacing the non-stick liquid with the recording ink.

[Problems to be Solved by the Invention] However, this backflow prevention valve for non-fixed liquid does not ensure smooth supply of recording ink to the print head during printing operation.
Conventional non-return valves are structurally complex, and as a result,
It was also expensive.

The present invention has been made in view of this situation, and can completely prevent the non-stick liquid from flowing back into the ink tank when replacing the non-stick liquid with the recording ink. An object of the present invention is to provide a single-head-integrated disposable ink cartridge with a simple structure that can extremely smoothly supply recording ink to a print head during operation.

[Means for solving the problem] The structure of claim 1 of the present invention for achieving this object is as follows:
Ink cartridges with pressurized ink recovery system,
A check valve is installed between the pressurizing mechanism and the ink tank, which closes when the liquid pressure in the ink passage leading to the print head and the pressurizing mechanism is higher than the liquid pressure on the ink tank side. There is a particular thing.

A second aspect of the invention resides in that, in the ink cartridge with a pressurized ink recovery system according to the first aspect, the ink passage from the check valve to the print head is filled with non-stick liquid.

Furthermore, the configuration of claim 3 provides an ink cartridge with a pressurized ink recovery system according to claim 1 or 2,
The check valve is maintained in a closed position by the biasing action of a spring member.

Effects] The effects of claims 1 and 2 of the present invention based on this configuration are provided in an ink cartridge equipped with a pressurized ink recovery system.
By automatically opening and closing the check valve using the pressure difference between the liquid pressure in the ink passage from the print head to the liquid chamber of the pressure mechanism and the liquid pressure on the ink tank side, non-stick liquid can be removed. The purpose is to prevent the non-fixed liquid from flowing back into the ink tank when replacing the recording ink, and also to smoothly supply the recording ink to the print head during the printing operation.

Further, the effect of claim 3 is that in the ink cartridge with a pressurized ink recovery system according to claim 1 or 2,
In order to increase the degree of freedom in the installation position of the check valve, the check valve and the pressurizing operation part of the pressurizing mechanism are designed to be separable.
That's true.

[Example code] Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIG. 1 is a schematic sectional view showing a first embodiment of an ink cartridge according to the present invention which is equipped with a pressurized ink recovery system.

In the figure, an ink cartridge 1 equipped with a pressurized ink recovery system according to the present invention includes an ink tank 3 containing an ink 2 for inkjet recording inside, and a printing radish equipped with a plurality of ink discharge nozzles 4a. 4, a tank-side ink passage 5 communicating with the lower part 3a of the ink tank 3, a supply vibro communicating with the print head 4, and a supplement installed between the tank-side ink passage 5 and the supply vibro. It is composed of a pressure mechanism section 7.

In this case, the pressurizing mechanism section 7 includes a liquid chamber 8, a pressurizing operation section 9, and a check valve 10.
The check valve 10 and the check valve 10 are made as a flexible member integrally made of a chemical-resistant material such as synthetic rubber.

Further, the check valve 10 is arranged in such a shape and state that its collar portion 10a can close the opening 5a of the tank-side ink passage 5 from inside the liquid chamber 8. On the other hand, the ink tank 3 is configured so that a pressure action such as atmospheric pressure is applied to the recording ink 2 inside the ink tank 3, and by pushing open the check valve 10 by this pressure action, the recording ink inside the tank 3 is The printing ink 2 is sent to the print head 4 via the tank-side ink passage 5, the pressurizing mechanism 7, and the supply vibro.

Before use, the ink cartridge 1 of the illustrated embodiment having such a configuration is filled with ink 2 from the ink tank 3 to the opening 5a of the tank-side ink passage 5, and the ink of the print head 4 is filled with ink 2. The area from the discharge nozzle 4a through the supply vibro to the check valve 10 of the pressurizing mechanism section 7 is filled with a non-fixed liquid having an appropriate composition.

When using the ink cartridge 1 in this state, the cartridge 1 is set in a predetermined location of an inkjet printer (not shown), and the pressure mechanism section 7 is turned on via an appropriate operating means before starting the printing operation. Pressure operation part 9
By pressing and repeating this pressing operation,
The non-fixed liquid in the area from the print head 4 to the liquid chamber 8 of the pressure mechanism section 7 is discharged from the ink discharge nozzle 4a of the print head 4, and the recording ink 2 is injected into that area.
inflow.

That is, when the pressurizing operation part 9 of the pressurizing mechanism part 7 is pressed, during that time, the pressure of the non-fixed liquid overcomes the pressure effect of the atmospheric pressure etc. applied to the recording ink 2, and the backlash is prevented. valve 10
This prevents the non-fixed liquid from flowing back from the inside of the liquid chamber 8 to the tank-side ink passage 5.

On the other hand, when the pressure on the pressure operation section 9 is stopped, as the shape of the pressure operation section 9 returns to its original shape, the non-fixed liquid in the area from the print head 4 to the liquid chamber 8 of the pressure mechanism section 7 The liquid pressure in the tank side ink passage 5 decreases, creating a liquid pressure difference between it and the ink pressure in the tank side ink passage 5, so the check valve 1° opens and the recording ink 2 in the tank side ink passage 5 flows into the liquid chamber 8. flow into.

Therefore, if the pressing operation on the pressurizing operation section 9 is repeated,
The non-fixed liquid filling the area from the print head 4 to the liquid chamber 8 is successively replaced with the recording ink 2.

The inkjet printer is then able to start printing, but during the printing, the pressure of the ink 2 in the liquid chamber 8 decreases as the recording ink 2 is consumed. Since the stop valve 1o is opened by the inflow pressure of the recording ink 2 from the ink tank 3, the recording ink 2 is supplied extremely smoothly during the printing operation.

FIG. 2 is a schematic sectional view showing a second embodiment of the ink cartridge according to the present invention. This example is characterized in that there is no tank-side ink passage 5 as in the first example, and the check valve 20 directly opens and closes the opening 3b in the lower part 3a of the ink tank 3. That is, the check valve 20 in this case is made of a chemically resistant material such as synthetic rubber, as in the first embodiment, and is attached to the pressurizing operation part 9.
The outer surface thereof is formed as an umbrella-shaped portion (truncated cone) 20a that becomes thicker downward from the tip.
The hem portion of 0a is formed to have a thin wall thickness so as to fit into the tank lower opening 3b.

When replacing the non-stick liquid with the recording ink, the hem portion of the umbrella-shaped portion 20a closes the tank lower opening 3b from inside the liquid chamber 8 to prevent the non-stick liquid from flowing back into the tank 3. During the printing operation, the pressure of the ink 2 in the liquid chamber 8 decreases as the recording ink 2 is consumed, and the umbrella-shaped portion 20a is pushed down by the inflow pressure of the recording ink 2 from the ink tank 3. Therefore, the recording ink 2 is supplied extremely smoothly during the printing operation, as in the first embodiment.

FIG. 3 is a schematic sectional view showing a third embodiment of the ink cartridge according to the present invention. This example is characterized in that the check valve of the second example is constructed in place of a plate spring type structure. The check valve 30 in this case is configured as a separate member from the pressurizing operation section 9 of the pressurizing mechanism section 7. That is,
The check valve 3° has a backing member 30a made of a chemical-resistant material that elastically contacts the opening 3b of the lower part 3a of the ink tank 3, and a plate spring fixed to the support portion 8a of the liquid chamber 8 in a cantilever manner. It has a structure in which it is attached to the free end of 30b.

Also in this case, when the non-fixed liquid and the recording ink are replaced, the backing member 30a is moved to the liquid chamber 8.
The bottom opening 3b of the tank is closed from the inside to prevent non-fixed liquid from flowing back into the tank 3, and during printing operation, when the liquid pressure of the recording ink 2 in the liquid chamber 8 decreases, the non-fixed liquid is removed from the ink tank 3. The recording ink 2 is allowed to flow in, and the recording ink 2 is smoothly supplied during the printing operation.

FIG. 4 is a schematic sectional view showing a fourth embodiment of the ink cartridge according to the present invention. This example is characterized in that the check valve of the plate spring type structure in the third example is configured as a check valve of a structure combining a ball and a coil spring.

The check valve 40 in this case is also the pressurizing operation section 9 of the pressurizing mechanism section 7.
It is constructed as a separate member. That is, this check valve 4
0 is composed of a non-metallic ball 40a made of, for example, a chemical-resistant material that contacts the opening 3b of the lower part 3a of the ink tank 3, and a coil spring 40b that biases and supports the ball 40a from below. A small hole 8b is formed in the cylindrical support portion 8a of the liquid chamber 8 in which the coil spring 40b is accommodated. In this case as well, when replacing the non-stick liquid with the recording ink, the ball 40a closes the tank lower opening 3b from inside the liquid chamber 8 to prevent the non-stick liquid from flowing back into the tank 3. During the operation, when the liquid pressure of the recording ink 2 in the liquid chamber 8 decreases, the recording ink 2 is allowed to flow in from the ink tank 3 to smoothly supply the recording ink 2 during the printing operation. .

In this way, in the ink cartridge equipped with the pressurized ink recovery system according to the present invention, the pressure difference between the liquid pressure in the ink passage from the print head to the liquid chamber of the pressure mechanism and the liquid pressure on the ink tank side is reduced. Since the check valve is configured to automatically open and close using the non-stick liquid, the check valve is automatically opened and closed while the pressurizing operation section of the pressurizing mechanism section is being pressed when replacing non-stick liquid with recording ink. When the valve is closed to prevent non-fixed liquid from flowing back into the ink tank and the pressure on the pressurizing operation part is stopped, the check valve automatically opens to prevent recording ink from flowing from the ink tank. It has become possible to supply recording ink to the print head extremely smoothly during printing operations. Note that the closing pressure applied to each check valve is set to be approximately the same as the pressure, such as atmospheric pressure, applied to the ink tank as described above.

Although several embodiments have been described above, the present invention is not limited thereto, and various modifications can be made without changing the gist thereof. For example, the filling point for non-sticky liquid may be located closer to the ink tank than the check valve, and the shape and structure of the check valve and pressurizing operation part may be appropriately shaped and structured. can be used.

[Effect of the invention] As described above, when claims 1 and 2 of the present invention are used, backflow of the non-stick liquid to the ink tank side is completely prevented when replacing the non-stick liquid with the recording ink. It is now possible to realize a head-integrated disposable ink cartridge with a simple structure that can supply recording ink to the print head extremely smoothly during printing operation. 3, it becomes possible to increase the degree of freedom in the installation position of the reverse valve.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing a first embodiment of an ink cartridge equipped with a pressurized ink recovery system of the present invention, FIG. 2 is a schematic cross-sectional view showing a second embodiment of the present invention, and FIG. FIG. 4 is a schematic cross-sectional view showing a third embodiment according to the present invention, and FIG. 4 is a schematic cross-sectional view showing a fourth embodiment according to the present invention. 1... Ink cartridge, 2... Recording ink,
3... Ink tank, 3a... Tank lower part, 4...
・Print head, 4a... Ink discharge nozzle, 5...
Tank side ink passage, 3b, 5a...opening, 6...
Supply pipe, 7... Pressure mechanism section, 8... Liquid chamber,
8a... Support part, 9... Pressure operation part, 10.2o.
3o・4゜...Check valve, 10a...Brim part, 20a...
... Umbrella-shaped part, 30a... Backing member, 30b.
...Plate spring, 40a...Ball, 40b...Coil spring. 1 Ink cartridge Figure 1 Figure 2 Figure 3 Figure 4

Claims (3)

[Claims] (1) In an ink cartridge with a pressurized ink recovery system, between the pressure mechanism and the ink tank, the fluid pressure in the ink passage from the print head to the pressure mechanism is higher than the fluid pressure on the ink tank side. An ink cartridge with a pressurized ink recovery system, which is equipped with a check valve that closes when the ink is removed. (2) The ink cartridge with a pressurized ink recovery system according to claim 1, wherein the ink passage from the check valve to the print head is filled with non-stick liquid. (3) The ink cartridge with a pressurized ink recovery system according to claim 1 or 2, wherein the check valve is maintained in a closed position by a biasing action of a spring member.