JP2003334971A - Ink residual amount detection stabilizing unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent erroneous detection of the ink residual amount due to ink droplets or ink bubbles, in an optical system ink residual amount detection unit. <P>SOLUTION: An operation of wiping off the prism surface is executed by providing in the ink tank a pendulum-like plate for wiping off the surface of a prism for detecting the ink residual amount in an ink tank, and swinging the pendulum at the time the ink runs low. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
It relates to an ink remaining amount detecting means of an ink tank of a printer.

[0002]

2. Description of the Related Art In recent years, ink jet printers have become widespread because they are easy to be made light and compact, high definition is possible, power consumption is low, and running cost is low.

Since this ink jet printer prints by ejecting only the ink necessary for printing, the ink consumption is small and the ink tank is also small.

Since the ink tank is small and the amount of ink in the ink tank is small, it is very difficult to detect the remaining amount of ink, and various methods for detecting the remaining amount of ink have been used.

For example, there is a method of recording how many drops of ink are ejected at the time of printing and detecting the remaining amount of ink, but it requires a capacity of a storage medium (memory) for recording the ejected information, and Not only this storage processing time is required, but also when the ink tank is once removed and attached again during use, there is a problem that the remaining ink amount cannot be accurately detected.

Therefore, a means for detecting the remaining amount of ink by the transmitted light so that the light passes through the ink tank has been considered.
Due to the ink droplets adhering to the wall surface of the ink tank and the generation of bubbles, there have been many inconveniences that the accurate remaining ink amount cannot be detected.

Next, a method has been used in which a prism is provided at the bottom of the ink tank, light is emitted from the outside, and the amount of ink remaining is detected by the light reflected by the prism. With this method, there is no influence of the ink adhering to the wall surface of the ink tank, and it has become possible to detect a fairly stable ink remaining amount.

[0008]

However, even in the above example, due to ink droplets or ink bubbles adhering to the prism in the ink tank, the reflected light from the prism is the same as when there is ink remaining. However, there is a problem in that erroneous detection of the remaining ink amount occurs.

An object of the present invention is to remove ink drops and ink bubbles adhering to the prism.

[0010]

In the present invention, means for wiping pendulum-shaped ink droplets or ink bubbles is provided in the ink tank. As a result, when the ink level decreases,
It has the function of removing ink drops and ink bubbles adhering to the prism surface.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In this embodiment, FIG. 1 shows an example of a carriage portion of an ink jet printer (not shown), where 1 is a carriage, 2 is a print head, 3 is an ink tank, and 4 is an ink tank. Carriage instructions.

FIG. 2a is a side view of the ink tank 3 and
1 is an ink supply port to the print head, 12 is a prism, 13 is ink, 14 is a light emitting portion of an optical sensor,
Reference numeral 15 is a light receiving portion of the optical sensor.

FIG. 2b is a diagram showing an ink tank in which the remaining amount of ink is low.

FIG. 2c is a diagram in which the ink remaining amount is low and ink drops 16 are attached to the prism.

Reference numeral 17 in FIG. 3a is an ink drop removing rod.

FIG. 3c is a diagram showing the positional relationship between the ink drop removing rod 17 and the ink drops.

FIG. 4a is a side view of the ink tank, showing that the ink drop removal rod is located next to the prism.

FIG. 4b is a side view of the ink tank, which is swung to the left as the carriage moves when the ink in the ink tank is low.

FIG. 4c is a side view of the ink tank, which is a view swung to the right as the carriage moves when the ink in the ink tank is low.

Next, this embodiment will be described step by step.

As shown in FIG. 1, in a general ink jet printer, the print head 2 ejects ink onto a print medium (not shown) while the carriage 4 moves left and right to perform a print operation.

At this time, the ink 13 is supplied to the print head 2 through the ink supply port 11.

FIG. 2A shows that the remaining amount of ink in the ink tank 3 is that the light emitted from the light emitting portion of the optical sensor hits the prism 12 and is refracted by the ink 13 to return to the light receiving portion of the optical sensor. FIG. 6 is a diagram showing a state where it is determined that there is ink remaining.

In FIG. 2b, the amount of ink remaining in the ink tank is reduced, and the light emitted from the light emitting portion of the optical sensor changes its refraction angle, so that the light is returned to the light receiving portion of the optical sensor. FIG. 11 is a diagram showing a state in which it is determined that there is no ink remaining because there is no ink.

In FIG. 2c, although the ink remaining amount is small as in FIG. 2b, the ink drops and bubbles 16 are attached to the prism, so that the ink remaining amount as shown in FIG. 2a exists. FIG. 9 is a diagram showing a case where it is erroneously detected that there is ink remaining by refracting the same as at time.

In order to improve this problem, it is sufficient to remove the ink droplets and bubbles 16 that cause the erroneous detection. Therefore, the present invention has the following structure.

As shown in FIG. 3a, the ink drop removing plate 17 is provided in the ink tank and fixed at the upper part of the drawing.
The ink drop removing plate has a structure that can move like a pendulum.

FIG. 3c is a diagram showing that the ink droplet removing plate is spaced apart from the prism for wiping the ink droplets.

Next, the operation of the ink drop removing plate for removing ink drops and ink bubbles on the prism surface will be described.

FIG. 4a shows that when the ink tank has a sufficient amount of ink, the ink drop removing plate hardly sways left and right due to the resistance of the ink.

FIGS. 4b and 4c show a state in which when the ink in the ink tank is reduced, the carriage moves to swing the ink drop removing plate to the left and right, so that the ink drops on the prism are wiped off.

[0032]

As described above, by installing the plate for removing the ink droplets adhering to the surface of the prism for detecting the ink remaining amount in the ink tank as described above, when the ink remaining amount decreases, the carriage By swinging like a pendulum along with the movement, the ink droplets adhering to the surface of the prism for detecting the remaining ink amount are wiped off. Therefore, it is an advantage of the present invention to prevent malfunction of the remaining ink amount detection.

This ink drop removing plate can be manufactured at low cost,
Since it can be made of various materials, it is possible to improve the accuracy of remaining ink amount detection at low cost.

[Brief description of drawings]

FIG. 1 is an example of a carriage portion of an inkjet printer.

FIG. 2 is a side view of the ink tank 3.

FIG. 3 is an ink drop removing rod.

FIG. 4 is a side view of the ink tank.

Claims (2)

[Claims] 1. An ink jet recording apparatus (hereinafter, referred to as an ink jet printer) in which a print head and an ink tank are arranged on a carriage and the carriage moves during printing to print, and a pendulum plate is provided in the ink tank. An ink tank remaining amount detecting and stabilizing device having means for swinging the pendulum plate by movement of the carriage. 2. The ink tank remaining amount detecting and stabilizing device as claimed in claim 1, wherein a pendulum-shaped plate in the ink tank contacts an inner wall of the ink tank.