JPS6344548B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ink storage container, and more particularly to an ink storage container capable of detecting the amount of ink remaining in the ink storage container.

Conventionally, inkjet printers record information such as letters and pictures in the form of dots by colliding liquid ink with droplets of paper according to the information to be recorded. Therefore, ink must be stored as a liquid, like gasoline in a car.Furthermore, if it scatters, it will stain the surrounding area, so ink containers must be stored to prevent ink from leaking due to vibrations or shocks. Must be stored. In addition, physical properties such as surface tension and viscosity must be kept at constant values, and evaporation of the constituent components of the ink must be prevented as much as possible. Furthermore, in the case of inkjet printers that use pipes to eject ink by applying voltage only when necessary without pressurizing the ink, the ink liquid level must be kept constant and maintained at the same pressure as the atmosphere. is necessary.

In any case, when the amount of ink remaining in the ink container becomes low, it is necessary to replenish it to the amount necessary for printing, so the remaining amount of ink is displayed, and at least when the remaining amount becomes low, Warnings must be issued to ensure good printing at all times.

Conventionally, a mechanism as shown in FIG. 1 has been used to detect the amount of ink remaining in an ink container. That is, in the mechanism shown in FIG. 1A, a float 3 containing a magnet is suspended in a side channel 5 of an ink container 1, and a reed switch 4 is disposed opposite the side channel 5. Ink 2 in ink container 1
When the amount decreases, the float 3 in the side channel 5 descends according to the liquid level of the ink 2, and the reed switch 4 is operated, thereby displaying the remaining amount of ink. Furthermore, the mechanism shown in FIG. 1B uses a light emitting means 6 and a light receiving means 7 instead of the reed switch 4 to detect the remaining amount of ink. This is a method in which the means 7 receives light from the light emitting means 6 to detect the remaining amount of ink.

In any of these conventional devices, a non-contact type detection mechanism is used, and the method is reliable and reliable for detecting the amount of ink remaining. However, the ink storage containers used in inkjet printers are
Since the structure shown in the figure is preferable, it is not suitable for use with a conventional ink remaining amount detection device. In other words, the ink container used in an inkjet printer has a three-layered bag 1 as shown in Figure 2.
Ink 11 is stored in this ink storage bag 1.
0 is entirely housed in a case 13 provided with a ventilation hole 12, and the ink 11 is discharged to the outside through a discharge pipe 14 and a rubber stopper 15 arranged in an ink storage bag 11. Specifically, the ink is taken out by connecting the insertion needle 16 to the outlet pipe 14 led to the rubber stopper 15. Also, ink storage bag 1
As shown in FIG. 3, 0 is a nylon external protective plastic thin film 17 with a thickness of 5 to 10μ, an aluminum thin film 18 with a thickness of about 10μ to prevent ink evaporation and deterioration due to ultraviolet rays, etc.
Internal main bag 1 made of 70μ thick polyethylene thin film
It consists of 9.

In the case of an ink storage container configured in this manner, ink is replenished by replacing the entire case, and the old case is discarded. In addition, the ink storage bag 10 is a flat bag, and the variation in the ink level from when it is full to when it is empty is only about 10 mm at most, and the ink storage bag 1
Since the bag 0 is flat and flexible, it easily deforms according to atmospheric pressure, and a conventional ink remaining amount detection mechanism cannot provide an accurate and reliable ink storage container.

Therefore, the present invention has been made in view of these points, and provides an ink residual amount that can reliably and reliably detect the amount of ink remaining in an ink container used in an inkjet printer using a simple structure but an inexpensive means. The object of the present invention is to provide a quantity detection device.

According to the present invention, focusing on the fact that the ink storage container is a flat flexible bag made of a thin plastic film, the strain gauge is attached to a part of the ink container to measure the distortion of the ink storage container that deforms depending on the amount of remaining ink. This method attempts to detect the amount of ink remaining.

Next, embodiments of the present invention will be described in detail using FIGS. 4 to 6.

Figure 4 shows the ink storage bag 1 shown in Figure 2.
An ink storage bag 20 similar to that shown in FIG.
This ink storage bag 20 is made of a composite plastic thin film with a three-layer structure as shown in FIG. 22 are provided. In addition, a strain gauge 23 is attached to a part of the ink storage bag, for example, at a position corresponding to the top of the ink outlet pipe 22, and its electrode lead wire 2 is attached.
4 and 24' are pulled out to the outside. This strain gauge is connected between the base of the transistor Tr and the ground as shown in FIG.
A light emitting diode LED is connected to the collector of this transistor via a resistor R2. Further, a resistor R1 is connected to the base of the transistor Tr so that a voltage divided by the resistor R1 and the resistance value RX of the strain gauge 23 is applied to the base of the transistor Tr.

Next, the operation of the remaining ink amount detection device configured as described above will be explained. When the remaining amount of ink decreases, the shape of the ink storage bag 20 changes due to atmospheric pressure, and when the remaining amount falls below a predetermined amount, the ink storage bag 20 collapses in shape as shown in FIG. 2
3 curves along the lead-out pipe 22 and deforms from the position shown by the dotted line to the blacked-out position in FIG. 5, and the resistance value of the strain gauge 23 increases.

That is, when the remaining amount of ink is large, the resistance value RX of the strain gauge is small and the voltage division ratio determined by R1 and RX is small, so the transistor Tr cannot be made conductive and the light emitting diode LED does not light up. On the other hand, as the remaining amount of ink decreases, the strain gauge 23 begins to bend as shown in FIG. 5, and the value of RX gradually increases, until finally R1
As the ink approaches the ink level, the transistor Tr becomes conductive and current flows through the light emitting diode LED, which emits light to warn that the ink is running out.

As explained above, the present invention provides a strain gauge at a position corresponding to the top of the ink outlet tube of the ink storage bag, and uses this strain gauge to detect the distortion of the ink storage bag that deforms depending on the remaining amount of ink. Since a strain gauge is installed on the ink outlet tube, the strain gauge can reliably detect distortion of the ink storage bag due to changes in the remaining ink level. The remaining amount of ink can be accurately detected with a simple configuration.

[Brief explanation of the drawing]

1A and 1B are explanatory views explaining the structure of a conventional device, FIG. 2 is a sectional view showing the structure of an ink storage container used in the present invention, and FIG. 3 is an illustration of the ink storage bag shown in FIG. 2. Some enlarged sectional views, FIGS. 4 to 6, show embodiments of the present invention. FIG. 4 is a plan view of the ink storage bag, and FIG. 5 is a sectional view showing deformation of the strain gauge. FIG. 6 is a circuit diagram for detecting the remaining amount of ink. DESCRIPTION OF SYMBOLS 10...Ink storage bag, 11...Ink, 12...Vent hole, 13...Case, 14...Leading pipe, 20...
Ink storage bag, 22...Leading pipe, 23...Strain gauge.

Claims (1)

[Claims] 1. A flat ink storage bag formed of a flexible thin film, an ink outlet tube arranged such that one end is located inside the ink storage bag and the other end is located outside the ink storage bag, and the ink storage and a strain gauge attached to a position corresponding to the top of the ink outlet tube of the bag, and the strain gauge detects the distortion of the ink storage bag that deforms according to the remaining amount of ink to detect the remaining amount of ink. An ink storage container characterized by: