JPH0220887A - Residual toner detecting device - Google Patents

Abstract

PURPOSE:To inexpensively detect residual toner without malfunction and without being affected by the material of developer by detecting the toner residual from the moving state of a movable member obtained from a detecting means detecting the developer pressing position on the movable member. CONSTITUTION:Owing to the rotating action of a cam shaft 5, a detecting lever 4 rotates clockwise around a fulcrum C, and its top moves to a position H in the direction of an arrow A. When the cam shaft 5 rotates further, the detecting lever 4 rotates counterclockwise around the fulcrum C due to its self-weight, and its top moves in the direction of an arrow B, presses the surface of the toner 3 and stops. A photointerrupter 6 is installed in an appropriate position in response to the residual of the toner 3. Even if the residual of the toner 3 is less, the top of the detecting lever 4 moves greatly, whereby its end crosses the photointerrupter 6. Thus, toner residual can be detected inexpensively and surely, regardless of the soil of the movable member and the material of the toner.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a remaining toner amount detection device that can be used in an image forming apparatus.

"Prior Art J" Conventionally, as a means for detecting the amount of toner remaining in the developer in an image forming apparatus using an electrophotographic process, there have been methods for detecting the presence or absence of toner using a piezoelectric element, and methods for detecting the presence or absence of toner using a photo sensor. Some methods have been used, such as those that detect the toner directly or those that utilize changes in electric field capacitance depending on the presence or absence of toner.

``Problems to be Solved by the Invention'' However, in the above conventional example, for example, using an expensive piezoelectric element is disadvantageous in terms of cost as toner containers are increasingly being made into cartridges. Internal cleaning means are required;
It is also more likely to malfunction. Further, in the method that utilizes changes in electric field capacitance depending on the presence or absence of toner, there is a problem that detection may not be possible depending on the toner material.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and provide a toner remaining amount detection device that is inexpensive, does not malfunction, and is not affected by the material of the developer.

"Means for Solving the Problems" The present invention is a developer remaining amount detection device in an image forming apparatus using an electrophotographic process, which includes a movable member that presses the developer when it moves up and down. A remaining toner amount detection device that includes a drive means for the movable member and a detection means for detecting a developer pressing position of the movable member, and detects the remaining amount of toner based on the downward movement state of the movable member obtained by the detection means. It is.

"Example" Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a first embodiment of the present invention, and is a longitudinal sectional view of a toner container.

Toner 5 is sealed in the outer box 1. Developing sleeve 2
The toner 6 is attracted to the surface, carried out from the outer box 1, and deposited on the surface of a photoreceptor (not shown) for development. The detection lever 4 rotates in the directions of arrows A1 and B with C in the figure as a fulcrum, and when the remaining amount of toner 6 decreases, one end protruding outside the outer box 1
It has a structure that crosses the photointerlab taro. A camshaft 5 rotatably supported by the outer box 1 is rotated in the direction of the arrow in the figure by a power source (not shown). Due to this rotational movement, the detection lever 4 moves to a position H indicated by a broken line. The central processing unit CPU 7 receives the detection signal S1 from the photointerlab taro and outputs a toner presence signal S2 to an external device or the like.

Next, the operation of the above configuration will be explained. First, the camshaft 5 is rotated in the D direction constantly or at predetermined timing by a power source (not shown). Due to the rotational operation, the detection lever 4 rotates clockwise around the fulcrum C, and the tip of the detection lever 4 moves in the direction of arrow A to a position H indicated by a broken line. When the camshaft 5 further rotates, the detection lever 4 follows the rotation of the camshaft 5 due to its own weight, rotates counterclockwise around the fulcrum C, and its tip moves in the direction of arrow B, pressing the surface of the toner 6. and stop.

The photo interlab taro is provided at an appropriate position depending on the remaining amount of toner 3 to be detected. When the remaining amount of toner 3 becomes low, the tip of the detection lever 4 moves more in the direction of arrow B, and At the position , the rear end of the detection lever 4 will cross the photointerlab taro.

FIG. 2 shows the detection signal S1 of the photointerlab Taro and
In the time chart showing the relationship between the toner presence signal S2,
When the pulses of the detection signal S1 are input continuously for a predetermined time period T or when the number of pulses reaches a predetermined value, U7 makes the toner presence signal S2 an L active signal and sends a message indicating that there is no toner to an external device (not shown), such as a display device. Output.

"Other Embodiments" In the above-described embodiments, the camshaft for driving the detection lever 4 was provided inside the toner container, but it goes without saying that similar effects can be obtained even if the camshaft is provided outside the toner container.

Further, although the detection lever 4 was moved to the toner surface due to its own weight, a spring or the like may be used as an aid, and an electromagnetic coil or the like may be used instead of a camshaft for lifting the detection lever 4.

FIG. 6 shows a second embodiment of the present invention, in which the same parts as in FIG. 1 are denoted by the same reference numerals.

In the first embodiment, a lever-shaped movable member was used, but a piston 4'' that moves in the vertical direction (arrows A' and B' in the figure) is provided.In addition, the camshaft 5° is , is located near the developing sleeve 2, and also has the effect of stirring the toner S. In the figure, when the camshaft 5' is rotated in the direction of the arrow in the figure, the piston 4e is lifted by the camshaft 51 and becomes the dotted line position. Once removed from the piston 4, the piston 4° falls due to its own weight, and its lower end presses against the surface of the toner 3 and stops.
As a result, a toner presence signal S1 opposite to that shown in FIG. 7 outputs an L active signal and indicates that there is no toner.

〔Effect of the invention〕

As explained above, by driving the movable member that moves up and down inside the powder toner container at a predetermined timing and detecting the downward movement position, it is now possible to easily detect the remaining amount of powder toner. Compared to other detection methods, (1) it is cheaper;

(2) The amount of toner is detected and stable regardless of the dirt on the movable member.

(6) Detection is possible regardless of the material of the toner.

(4) In addition to detecting the lower end position of the movable member, the remaining amount of toner is also detected based on the downward movement state.
Even if the toner surface becomes low from time to time, the absence of toner is not indicated, and the absence of toner can be reliably detected.

It is possible to achieve the following effects together.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a toner container showing a first embodiment of the present invention, FIG. 2 is a time chart, and FIG. 5 is a longitudinal sectional view of a toner container showing an embodiment of M2 in the present invention. be. 3. Toner 4. Detection lever 5. Camshaft 6. Photo interrupter 7. CPU0 Patent applicant Canon Corporation

Claims (1)

[Claims] 1. A developer remaining amount detection device in an image forming apparatus using an electrophotographic process, which comprises: a movable member that moves up and down and presses the developer when falling; a drive means for the movable member; It has a means for detecting the developer pressing position of the member, and according to the downward movement state of the movable member obtained by the detecting means,
A toner remaining amount detection device that detects the remaining amount of toner.