JPS58201027A - Device for detecting level of picture forming material - Google Patents

Abstract

PURPOSE:To detect a level precisely, by arranging a movable detecting part on the inside or side-wall of a vessel for a picture forming material at a position where one side of the detecting part is contacted with the picture forming material and restricting a piezo-electric vibrator through the detecting part. CONSTITUTION:The case 11 of a level detector 2 fitted to a toner storing vessel 1 is provided with an opening terminal 11a and a hole 11b on the opposite side to the terminal 11a and the hole 11b is covered with an elastic seat 12 constituting the movable detecting part. The elastic seat 12 is coupled with a piezo- electric turning fork 13 through a strut 7. When AC voltage is impressed to an oscillating piezo-electric element 14a fitted to one piece of the piezo-electric turning fork 13, the turning fork 13 is oscillated and the oscillation is picked up by an piezo-electric element 14b for receiving. Consequently, pickup voltage is changed by the existence of toner, making it possible to detect the existence of toner precisely.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to an apparatus for detecting the level of imaging materials such as toner, developer, and ink.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An electrophotographic copying apparatus will be described below as a suitable conventional example as a background of the image forming material level detection apparatus according to the present invention.

In this electrophotographic copying apparatus, toner such as carbon or magnetic powder is used as an image forming material, and is consumed each time copying is performed.

Therefore, when the remaining amount of toner becomes low, it is necessary to display or warn that replenishment is necessary. Since this toner is normally stored in a container, it is conceivable to provide a toner remaining amount detection device in the container.

Conventionally, a device for detecting the remaining amount of toner has a structure in which a piezoelectric vibrator is attached to the inside of a toner container or the side wall of the toner container, and the toner and the piezoelectric vibrator are in direct contact. In such a structure, if a sufficient amount of toner is in the container, the toner will adhere to the piezoelectric vibrator, and the mechanical vibration of the piezoelectric vibrator will be suppressed by the added mass of the toner.

Then, when the toner is consumed and contact with the piezoelectric vibrator disappears, the suppressed mechanical vibrations of the piezoelectric vibrator are released, and changes in the vibration of the piezoelectric vibrator at this time are captured. It displays or warns you that the amount of toner remaining is low.

However, the remaining toner amount detection device having such a configuration has the following drawbacks. In other words, since the toner directly adheres to the piezoelectric vibrator, even if the amount of toner decreases, the toner remains attached to the piezoelectric vibrator and restrains the piezoelectric vibrator. Therefore, there is a drawback that a malfunction occurs when detecting the level of the remaining amount of toner.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image-forming material level detection device that overcomes the above-mentioned problems.

The present invention also provides an image forming material level detection device that can be applied to image forming materials made of fine particles such as toner with strong cohesive force and adhesion, and also to image forming materials made of liquids such as developer and ink. The purpose is to

A further object of the present invention is to provide an image-forming material level detection device that is free from malfunctions, has a simple construction, and is small in size.

In other words, I love this invention! ii. The gist of the image-forming material level detection device includes at least a movable detection section, a piezoelectric vibrator, and a container containing the image-forming material, and the image-forming material level detecting device includes at least , a movable detecting section is arranged at a position where the - surface contacts the image forming material, and when a load is applied to the movable detecting section, the piezoelectric vibrator is restrained via the movable detecting section. That is.

The present invention will be described in detail below according to an illustrated embodiment.

FIG. 1 is a sectional side view of a main part showing an example in which an image forming material level detection device according to the present invention is applied to an electrophotographic copying apparatus.

In the figure, reference numeral 1 denotes a container containing toner, and level detectors 2 of 1 to toner are attached to the side wall of this container 1.

The detailed structure of this detector 2 will be explained as follows.

11 is a case having an open end 11a;
It has a hole 11b on the surface opposite to a. This hole 11
b is covered with an elastic sheet 12 constituting a movable detection section, and the elastic sheet 12 is fixed with adhesive around the hole 11b. 13 is a U-shaped piezoelectric tuning fork, and an excitation piezoelectric element 14a is glued to the inner surface of one vibrating piece 13a.
A receiving piezoelectric element 14b is provided on the inner surface of the other vibrating piece 13b.
is glued. This piezoelectric tuning fork 13 is attached to a substrate 16 by a support 15 attached to the bent portion. And the piezoelectric tuning fork 13 has its vibrating pieces 13a, 13
The surface b is in a positional relationship parallel to the surface of the elastic sheet 12. A support 17 is attached to the outer surface of one vibrating piece 13b of the piezoelectric tuning fork 13 near the midpoint of the vibrating piece 13b, and the other end of the support 17 is in contact with or fixed to the elastic sheet 12. The mounting position of this support 11 is not limited to the midpoint of the vibrating piece 13b;
It may be at the open end of or at any other location. In short, it may be determined as appropriate based on the relationship with the sensitivity for detecting the remaining amount of toner. Further, the material of this support column 17 may be rigid or elastic. In particular, if it is made of elastic rubber or the like, dimensional variations can be absorbed and manufacturing becomes easy.

A predetermined wiring pattern (not shown) is formed on the substrate 16, a capacitor (not shown) constituting a detection circuit and an oscillation hybrid integrated circuit component (not shown) are attached to predetermined locations, and the piezoelectric tuning fork 13 The wires are connected together with the support 15 (ground) and the lead wire as shown in FIG.

Further, the case is provided with a ventilation hole 11c, which can prevent the atmospheric pressure inside the case 11 from changing due to temperature changes and adversely affecting the movable detection section. This vent 1
1c may be used to draw out the output lead wire from the oscillation hybrid integrated circuit component or the like.

The detector 2 having such a configuration is attached such that the case 11 of the detector 2 is fitted into the hole 1a of the container 1 so that the elastic sheet 12, which is the movable detection part, is exposed to the container 1. .

Next, the functions of the level detection device according to the present invention will be explained with reference to FIG.

First, when power is applied to the hybrid integrated circuit component 20 in which the amplifier is incorporated, a signal is applied to the excitation piezoelectric cable 14a, causing the vibrating pieces 13a and 13b to vibrate, and the vibration is detected by the receiving piezoelectric element 14b. positive feedback to the amplifier, resulting in sustained oscillation. Then, when a toner load is applied to the elastic sheet 12 of the movable detection section, the vibration of the detection vibrating piece 13b connected by the support column 17 is restrained, the positive feedback loop is broken, and the oscillation stops.

Based on this oscillation stop, a detection signal flows to the detection terminal 20a. This detection signal is supplied to the output circuit 30, and the output circuit 30 controls the next stage circuit.

This output circuit 30 may be incorporated into the case 11 shown in the first figure.

FIG. 3 shows a specific circuit example of the output circuit 30.

Further, FIG. 4 shows a block diagram including a display circuit or a control circuit as a next-stage circuit connected to the output circuit. The display circuit or control circuit includes a remaining power indicator lamp, a notification system circuit using sound, audio, etc., a relay circuit,
Although the piezoelectric tuning fork is driven by automatic oscillation in the above-described embodiments that include a drive circuit, it may be configured to be driven by external excitation.

In the configuration shown in FIG. 1, a silicone rubber sheet with a thickness of 100 μm was used as the elastic sheet 12.

Further, as the piezoelectric tuning fork 13, a tuning fork made of Elinvar-1 vibrating pieces having a width of 2.5 mm, a length of 17 mm, an interval between the vibrating pieces of 3.5 n+m, and a resonance frequency of about 1.5 KH2 was used. Inside the container 1, there is an elastic sheet 1 which is a movable detection part.
When the samples 1 to 2 were housed so that a load of 2 mg 7 mm2 was applied to the piezoelectric tuning fork 13, it was confirmed that the vibration of the piezoelectric tuning fork 13 stopped. Further, when the toner was removed and the load applied to the elastic sheet 12 was removed, the piezoelectric tuning fork 13 started vibrating.

Therefore, as is clear from the results of this experiment, by using the level detection device configured as described above, it is possible to detect the remaining amount of toner, and it is possible to accurately notify the user when it is time to replenish toner.

The detection sensitivity can be adjusted by changing the cross-sectional area of the support 17, the mounting position of the support 17, and the material and thickness of the elastic sheet 12.

According to the embodiment described above, since the toner contacts the movable detection portion of the elastic sheet 12, the vibrating piece 1 of the piezoelectric tuning fork 13 directly
There is no risk of malfunction occurring due to adhesion to 3a and 13b.

In the above-described embodiment, an example was described in which the remaining amount, which is the lower limit amount of toner, is detected, but the present invention can of course be applied to an example in which the upper limit amount of toner is detected.

FIG. 5 is a sectional side view of a main part of another example of the image forming material level detection device according to the present invention.

The difference from the one shown in FIG. 1 is that the detector 2 is installed inside the container 1 containing the toner, and the piezoelectric vibrator 13 used as the piezoelectric vibrator constituting the detector 2 is a piezoelectric vibrator 13 instead of the piezoelectric tuning fork 13. The point is that it uses .

Therefore, with regard to FIG. 5, only the differences will be explained for convenience.

First, since the detector 2 is mounted inside the container 1, the case 11 serves as a so-called isolation member that prevents contact between the toner and the piezoelectric vibrator 13.

Moreover, the piezoelectric vibrating bar 13 has an excitation piezoelectric element 14a on one side thereof.
is adhered to the receiving piezoelectric element 14b, and the receiving piezoelectric element 14b is adhered to the other surface. One end of the piezoelectric vibrator 13 is attached to a substrate 16 by a support 15, and a support 17 is attached to the other end. This support column 17 is in contact with or fixed to the elastic sheet 12.

Although the support column 17 is attached to the piezoelectric sound piece 13, it may be constructed integrally with the piezoelectric sound piece 13.

FIGS. 6 and 7 show a modification example in which the protrusion 13c of the piezoelectric vibrator serves as the support 17, and although not shown, a piezoelectric element is bonded to one surface of the vibrator, and this A self-oscillation type piezoelectric resonator may be constructed by providing an excitation electrode and a feedback electrode on the piezoelectric element.

FIG. 8 is a circuit diagram of an example level detection device using a piezoelectric vibrating bar 13, and since it has the same configuration as the circuit diagram of the previous embodiment shown in FIG. Further explanation will be omitted.

Next, FIGS. 9 to 11 show still other embodiments of the present invention, and for the sake of convenience, only the differences will be explained.

In FIG. 9, a hole 41a is provided in a case 41, and a seam 1-43 is attached to a step formed around the hole 41a using an elastic adhesive 42. In this case, the sheets 1 to 43 may be non-elastic materials such as metal plates or resin plates.

In this embodiment, since the sheet 43 is displaced by the elastic adhesive 42, the load applied to the sheet 43 can be transmitted to the piezoelectric vibrator and vibrations can be restrained.

In FIG. 10, a sheet 43 with corrugations 43a around the periphery is fixed to the periphery of the hole 41a of the case 41.

In this embodiment, the sheet 43 is
can be displaced, so the sheet 43 functions as a movable detection section.

In FIG. 11, a part of a case 41 made of an elastic material such as rubber is made thin, and this thin part 41b is used as a movable detection part.

Although FIGS. 12 to 14 are similar to each other, they show modified examples of the piezoelectric tuning fork, in which the vibrating piece of the piezoelectric tuning fork 51 is processed without using the support 17 in FIG. A protruding portion 51a with a protruding portion is used instead of the support column 17.

In Fig. 14, 17a and 17b are attached to the excitation vibrating pieces 13a and 13b in the same way as the struts on the detection vibrating piece, and both vibrating pieces 13a and 13b have the same mass to achieve a resonance state. It has been stabilized.

FIGS. 15(a), (b), and (c) show the support method and vibration mode of the piezoelectric tuning fork, and FIG. 15(a) shows the case of the embodiment shown in FIG. 1. In addition, as shown in the same figure (b),
It may be supported at the midpoint of the excitation vibrating piece, or it may be supported at two locations, the bent portion of the tuning fork and the open end of the excitation vibrating piece, as shown in FIG.

Although not shown, in addition to the U-shaped piezoelectric tuning fork, a W-shaped piezoelectric tuning fork may be used as the piezoelectric vibrator, and in this case, it may be supported by an intermediate vibrating piece.

Alternatively, a strut, a protrusion, etc. may be formed on the movable detecting section to couple the movable detecting section and the vibrating piece.

Further, although the movable detection section and the vibrating piece are brought into contact with each other or fixed to each other by a branch, a protrusion, etc., a gap may be provided between them.

Furthermore, when using a piezoelectric tuning fork as a piezoelectric vibrator,
Although the receiving vibrating piece is restrained in this embodiment, a load may be transmitted to the excitation vibrating piece or both the receiving and excitation vibrating pieces to restrain their vibrations.

In the above-described embodiments, an example has been described in which the level of the amount of toner used as an image forming material in an electrophotographic copying machine is detected, but the present invention can also be applied to an example in which the level of a developer in a wet-type copying machine is detected.

It can also be applied to ink level detection used in inkjet printers.

Furthermore, the present invention can also be applied to level detection of 1 to 3 in electrophotographic copying devices used in facsimiles and the like.

[Brief explanation of drawings]

FIG. 1 is a side cross-sectional view of a main part showing an example in which an image forming material level detection device according to the present invention is applied to an electrophotographic copying apparatus, FIG. 2 is a circuit diagram of the detection device, and FIG. 3 is a specific example of an output circuit. FIG. 4 is a block diagram, FIG. 5 is a sectional side view of main parts showing another example of the level detection device for image forming material according to the present invention, and FIG. 6 and FIG. A side view showing a modified example, FIG. 8 is a circuit diagram of the detection device shown in FIG. 5, and FIG. 9 is a side view showing a modified example.
FIGS. 11 to 11 are side sectional views showing modified examples of the movable detection unit, FIGS. 12 to 14 are side sectional views showing modified examples of the piezoelectric tuning fork,
FIGS. 15(a), 15(b), and 15(c) are all schematic diagrams showing a method of supporting a piezoelectric tuning fork and a resonance mode. 1... Container containing toner, 2...
Toner level detector, 11...Case, 11
a... Opening end, 12... Elastic sheet,
13...Piezoelectric tuning fork, piezoelectric sound piece, 13a, 13b
... Vibration piece, 14a ... Piezoelectric element for excitation, 14b ... Piezoelectric element for reception, 15 ...
...Support, 16...Substrate, 17...
Prop. Patent application Person: Murata Manufacturing Co., Ltd. 5 Plans Section 4 Figure 2 + V Procedures Amendment September 18, 1982 1, Display of the case 1978 Patent Application No. 85222 2, Title image of the invention Relationship between forming material level detection device 3 and the person making the amendment case Patent applicant address 2-26-10 Tenjin, Nagaokakyo City, Kyoto Name (
623) Mura Co., Ltd. 1) Manufactured August 31, 1980 (shipment date) 5. Number of inventions increased by amendment 6. Full text of the specification to be amended 1. Engraving of the specification of the contents of the amendment (contents (no change)

Claims (3)

[Claims] (1) A position that includes at least a movable detection unit, a piezoelectric vibrator, and a container that accommodates an image-forming material, and that its surface contacts the inside or side wall of the container that accommodates the image-forming material. 1. A level detection device for an image forming material, characterized in that a movable detecting section is disposed in the movable detecting section, and when a load is applied to the movable detecting section, a piezoelectric vibrator is restrained via the movable detecting section. (2) The piezoelectric vibrator is a piezoelectric tuning fork.
1) The image forming material level detection device according to item 1). (3) The piezoelectric vibrator is a piezoelectric vibrator.
1) The image forming material level detection device according to item 1).