JPS59204570A - Apparatus for detecting ink residual amount of ink cartridge - Google Patents

Abstract

PURPOSE:To make it possible to certainly detect an ink residual amount, by such simple constitution that the ink residual amount is detected from the change in the quantity of light caused by the falling of the light blocking element integrally formed to a press plate. CONSTITUTION:A detection rod 17 is integrally added to a position shifted from the press part due to the press rod 10 on a press plate 4. A light quantity change detecting element 18 consists of photocouplers 18a, 18b which are, in turn, opposedly provided so as to interpose the detection rod 17 therebetween. When an ink bag 1 is fully filled, the detection rod 17 is present at a position for blocking the light quantity change detecting element 18 from light and, when the ink bag 1 is contracted with the consumption of ink, the press plate 14 is fallen and the detection rod 17 is also fallen with the falling of said press plate 14 while the light quantity change detecting element 18 detects the change in light quantity, that is, from dark to light.

Description

[Detailed description of the invention] Technique] L minutes-! The present invention relates to a device for detecting the remaining amount of ink in an ink cartridge in an on-demand inkjet printer.

[Kuwarai As a device for detecting the amount of ink remaining in an ink cartridge in an on-demand inkjet printer, a strain gauge is attached to an ink bag, etc., and the change in weight due to ink consumption is detected as a change in the resistance value of the strain gauge. A device for detecting the remaining amount of ink has been proposed, but it has drawbacks such as increased cost due to the use of an expensive strain gauge and the need for calibration work for the strain gauge. In addition, contacts are attached to the suppression plate that sandwiches the ink bag and to the bottom of the ink cartridge.
A device that detects the remaining amount of ink by contacting the contacts has also been proposed, but
This device has a complicated structure and requires the weight of the suppressing plate to operate the switch portion reliably, and this weight may pressurize the ink bag and cause the risk of ink dripping. In addition, devices have been proposed in which the ink bag is made of aluminum foil and the remaining amount of ink is detected by the change in capacity as ink is consumed, and a device in which the ink bag is made transparent and the remaining amount of ink is detected by the transmission of light. The material of the ink bag was limited to a conductive material such as aluminum foil in the former case, and a transparent material in the latter case. Furthermore, a device has been proposed in which a pair of electrodes are immersed in ink and the remaining amount of ink is detected from the change in resistance value between these electrodes, but this device has the disadvantage of a complicated structure.

OBJECT It is an object of the present invention to provide a device for detecting the remaining amount of ink in an ink cartridge in an on-demand inkjet printer, which eliminates the above-mentioned drawbacks, has a simple configuration, is reliable in one operation, and is inexpensive.

1--1 The configuration of the present invention will be described below based on examples.

FIG. 1 shows a cross-sectional view of an ink remaining amount detecting device C according to the present invention attached to an ink cartridge B filled diagonally in a carriage A. An ink bag 2 made of an elastic thin film such as a covered three-layer film is a housing of an ink cartridge B that accommodates the ink bag 1, and an opening 3 is provided in the lid 2a. A suppression plate 4 is disposed on the upper surface of the ink bag 1 within the ink cartridge housing 2, and presses the ink bag 1 evenly. 5 is ink bag 1
An ink outlet tube inserted into the ink supply cap 6 is connected to an ink supply mouthpiece 6 which is sealed after the ink bag l is loaded into the ink cartridge housing 2, and is closed with an elastic material 7 such as rubber. Reference numeral 8 denotes a handle provided on the outside of the ink cartridge housing 2. D is a pressing device for pressing the ink bag l from the opening 3 of the cartridge top lid 2a through the pressing plate 4 during initial ink filling and air bubble discharge, and is attached to the carriage A via a stay 9. . The pressing device is a pressing rod.
The pressing iron 10 is attached to the stay 9 so as to be movable in the vertical direction, and is disposed on the pressing plate 4 from a notch 12 provided in the carriage A.

Press the compression spring 11 (the knob 10 of the Rondo lO)
It is externally fitted between the stay 9 and the stay 9, and always urges the pressing rod IO upward.

E is a head part arranged on carriage A, and nozzle 13
have. The carriage A is provided with an ink supply needle 14 and an ink supply path 15, and an ink cartridge B is provided with an ink supply needle 14 and an ink supply path 15.
When loading, the ink supply needle 14 is inserted through the elastic body 7 into the ink outlet tube 5, so that the ink in the ink bag I passes through the ink outlet tube 5, the ink supply needle 14, and the ink supply path 15. and is supplied to the nozzle 13. Note that 16 is a guide rail for moving the carriage A, and 17 is a sliding bush.

The remaining ink amount detection device section C according to the present invention includes a detection rod 17 for shielding light and a light amount change detection element 18 such as a photo interlayer. The detection rod 17 is formed by deforming a part of the pressing plate 4 or joining a member to a part thereof, and is integrally added to the pressing plate 4 at a position away from the part pressed by the pressing rod IO. Since the pressing plate 4 to which the detection rod 17 is attached is disposed inside the ink cartridge B, when loading the ink cartridge B into the carriage A, in order to avoid interference of the detection rod 17 with the carriage A, the detection rod 17 is passed through a notch 12 provided in the carriage A. The light amount change detection element 18 consists of photocouplers 18a and 18b as shown in FIG.
These are arranged oppositely with the detection rod 17 in between,
When the cartridge B is completely loaded, the detection rod 17 reaches the detection position of the light amount change detection element 18.

When the ink bag 1 is full, the detection rod 17 is in a position that shields the light amount change detection element 18, and when the ink bag 1 contracts as ink is consumed, the pressure plate 4 placed on the ink bag 17 is moved. As it descends, the detection rod 17 also descends, and the light amount change detection element 18 detects a change in light amount, that is, from dark to bright. The light amount change detection element 18 is connected to an alarm device, a printing stop device, etc. (not shown), and is configured such that these additional means are activated by detecting a change in light amount. Although FIG. 1 shows the case where the ink cartridge B is loaded diagonally into the carriage, the cartridge is not loaded into the carriage and the cartridge holder is fixed below the printer frame and is loaded into the member. In this case, an ink supply tube is used to supply ink to the head section on the carriage.

FIGS. 3 and 4 show another embodiment, in which the pressing rod 10 directly presses a flat portion 17b provided at the top of a detection plate 17a integrally attached to the pressing plate 4. It is composed of When loading the ink cartridge B into the carriage A, the detection plate 17a, like the detection rod 17, passes through the notch 12 provided in the carriage A and is inserted up to the localization layer without interfering with the carriage A. A slit hole 17c is provided in the upper part of the detection plate 17a, and binary detection of dark→bright is performed by the light quantity change detection element 18 as in the previous embodiment. That is, when the ink bag l is full, the detection plate 17a is located at a position that shields the light amount change detection element, and when the ink bag l contracts as ink is consumed, the pressure plate 4 placed on the ink bag l is lowered, and the detection plate 17a is also lowered accordingly, the slit hole 17c reaches the detection position, and the light amount change detection element 18 detects the change in light amount. However, when detecting binary values as described above, the sensor may turn on or off due to minute vibrations or swinging of the carriage.
In such cases, the entire or part of the pressure plate is made of magnetic material, and a permanent magnet is attached to the bottom of the cartridge housing to prevent the ink from being emptied. The suppression plate may be attracted to the permanent magnet when the ink bag contracts.

Effects As described above, according to the present invention, the ink cartridge can be manufactured easily and inexpensively, and the remaining amount of ink can be reliably detected.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view for explaining one embodiment of the present invention;
2 is a top view of the main part of FIG. 1, FIG. 3 is a side sectional view for explaining another embodiment of the present invention, and FIG.
It is a perspective view of the main part of a figure. A... Carriage, B... Ink cartridge, D
... Pressing device, l... Ink bag, 2... Ink cartridge housing, 4... Pressing plate, 17... Detection member, 18... Light amount change detection element. 37

Claims (2)

[Claims] (1) In an on-demand inkjet printer, a light-shielding member is formed integrally with a part of a pressing plate disposed inside an ink cartridge housing and presses an ink bag uniformly, and is fixed to a carriage with the light-shielding member sandwiched therebetween. A remaining amount of ink in an ink cartridge is detected from a detection signal of the light amount change detecting element caused by lowering of the light shielding member as the ink is consumed. Device. (2) The ink cartridge of the ink cartridge according to claim (1), wherein the light shielding member is a suppressing portion formed by a pressing device that presses the ink bag during initial ink filling and when air bubbles are discharged. Remaining amount detection device.