KR0181119B1 - Apparatus for sensing the quantity of toner of image forming system - Google Patents

Abstract

[Technical field to which the invention described in the claims belong]

The present invention relates to a toner amount detecting device for detecting the amount of remaining toner inside an image forming apparatus for forming an image in a product (LBP, copier, etc.) using an electrophotographic development method.

[Technical Challenges to Invent]

The present invention provides an image forming apparatus that can be manufactured at a low price by changing a piezoelectric sensor type toner detection sensor to a photo sensor type in a developer housing.

[Summary of the solution of the invention]

The present invention is a developer housing for storing toner on the upper part of the developing unit of the image forming apparatus, and an agitator having an agitating wing formed therein to stir to prevent agglomeration of the toner to transfer the toner to the developing roller of one side. And a driven sensing plate fixed to an end of the stirrer shaft on one side of the developing unit housing in which the stirrer is installed, a driving sensing plate fixed to a drive shaft outside the driven sensing plate, and a sensing sensor provided with a photo sensor outside the driven sensing plate and the driving sensing plate. The first and second driven sensing plates form a first locking protrusion protruding toward one side of the rib at the center of the first and second driven sensing holes, and the driving sensing plate is inwardly spaced from the first and second driving sensing holes. A driving shaft having a protruding second locking projection, the drive shaft is fixed to the groove formed in the rib of the driven sensing plate, the spring is fitted into the rib Both ends are fixed to the first locking projection and the second locking projection, respectively, and the photosensor of the sensing unit is configured to detect the remaining amount of the toner by the matching and mismatch of the sensing holes of the driven sensing plate and the driving sensing plate. It is done.

[Important Uses of the Invention]

The present invention is an image forming apparatus configured to change the piezoelectric sensor type toner detection sensor to a photo sensor type in a developer housing at a low price.

Description

Toner Level Detection Device of Image Forming Device

1 is a cross-sectional view of a developer in which a toner amount detection sensor is installed in a conventional image forming apparatus.

Figure 2 is an exploded perspective view of the residual toner amount detection device in the image forming apparatus of the present invention.

3 is a cross-sectional view of a developer in which a toner amount detection sensor is installed in the image forming apparatus of the present invention.

4 is an operational state diagram of a toner amount detection sensor of the image forming apparatus of the present invention.

5 is a waveform diagram showing an output signal of the toner detection sensor of the present invention.

* Explanation of symbols for main parts of the drawings

21: Developer 22: Developer Housing

23: stirrer 23: stirring blade

25 agitator shaft 26 driven sensing plate

27: rib 28: home

29: first locking projection 30: spring

31: first passive sensing hole 32: second passive sensing hole

33: drive shaft 34: drive sensing plate

35: first driving sensing hole 36: second driving sensing hole

37: second jamming projection 38: sensing unit

39: photosensor 39a: light emitting element

39 b: light receiving element 40: developer frame

41: toner

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner amount sensing device of an image forming apparatus, and more particularly, to a toner amount sensing device for sensing an amount of remaining toner in a developer for forming an image.

An electrophotographic developing method is most widely used for an image forming apparatus, and an image forming apparatus using a conventional electrophotographic developing method includes a recording apparatus such as a copying machine, a laser beam printer, and the like. As is well known, an image forming apparatus using an electrophotographic method forms an invisible electrostatic latent image on the surface of a photosensitive drum. Then, an image is formed on the surface of the photosensitive drum on which the electrostatic latent image is formed as a toner to visualize the image, which is transferred onto a sheet of paper and recorded.

The image forming apparatus as described above has a developer housing containing toner, which plays an important role in image quality formation, and the developer housing is provided with a toner detection device for detecting a storage amount of toner. Such a toner detection device is a technique well known to a person skilled in the related art such as a copy machine or a laser beam printer. The most representative method is a method using a toner sensor such as a piezoelectric sensor. If it decreases below a certain level, the toner sensor detects this and indicates that there is no toner.

A toner amount detecting device in the conventional image forming apparatus will be described with reference to FIG. 1 is a cross-sectional view of a developer in which a toner amount detection sensor is installed in a conventional image forming apparatus. The developing unit 1 of the image forming apparatus includes a developer housing 2 for storing toner, and the toner 6 includes a photosensitive drum ( The latent electrostatic image formed in 10) forms a visible image. The developer housing (2) is provided with an agitator (3) having a stirring blade (4) formed to stir to prevent agglomeration of the toner (6) to transfer the toner (6) to the developing roller (9) on one side. In the developing housing 2 below the stirrer 3, a toner sensor 11 which is a toner detection device for detecting the remaining amount of toner is installed. Above the developing roller 9, a duct blade 8 regulating the height of the toner and a photosensitive drum 10 are installed at one side. The toner sensor 11 for detecting the remaining amount of the toner 6 uses a piezoelectric sensor.

In the image forming apparatus 1 as described above, the toner 6 is supplied to the stirrer 3 inside the developing housing 2 and the toner 6 is rotated to the developing roller 9 on one side by rotation. 6) will be transferred. At this time, the toner 6 is developed on the photosensitive drum 10 in the developing roller 9, and the toner 6 inside the developer housing 2 in which the stirrer 3 is installed is consumed.

At this time, the piezoelectric sensor, which is a toner sensor 11 for detecting the amount of toner, detects the amount of toner when the toner 6 falls below the reference level, and generates a toner amount detection signal from the piezoelectric sensor 11, not shown. Is a display control signal indicating that the toner amount is insufficient to be displayed on the display unit.

Developing methods for developing a latent image formed on the surface of the photosensitive drum as a visible image using the image forming apparatus as described above are largely classified into a one-component development method, a two-component development method, and a magnetic brush development method. Such developing methods are well known to those skilled in the art and will not be described in detail in the present invention.

Conventional techniques for detecting the presence of toner using the piezoelectric sensor as described above or a similar toner sensor are disclosed in detail in US Pat. No. 4,647,185, which was invented by an inventor such as Takeda et al. And assigned to Canon Corporation in Japan. It is.

However, in the conventional image forming apparatus described above, in order to detect the remaining amount of toner, the price of the system is increased by detecting the state of the retention level of the toner by using a piezoelectric sensor type toner sensor which is very expensive, about 5 to 6 dollars. It resulted in an elevated problem.

In addition, due to the sensitivity of the toner detection portion of the piezoelectric sensor there was a problem that requires careful attention to handling.

Another problem is that the toner sensor is installed at one side of the developer housing, so when the toner flocks to the sensor unit, the toner is sensed by sensing the toner regardless of the total amount of toner.

The present invention has been made in order to solve the above problems, an object of the present invention is to develop a piezoelectric sensor type toner in the developer housing to change the detection sensor to a photo sensor type developer of an image forming apparatus that can be produced at a low price In providing.

Another object of the present invention is to provide a toner amount detecting device for detecting the remaining amount of toner by the remaining amount of toner in the developer housing.

The present invention for achieving the above object is a developer housing for storing the toner in the upper part of the developer housing of the image forming apparatus, and the agitator (agitator) formed with a stirring blade for transferring the toner to the developing roller of one side in the developer housing; And a driven sensing plate fixed to an end of the stirrer shaft on one side of the developing unit housing in which the stirrer is installed, a driving sensing plate fixed to a drive shaft outside the driven sensing plate, and a sensing sensor provided with a photo sensor outside the driven sensing plate and the driving sensing plate. The driving sensing plate has at least one sensing hole and a first locking protrusion protruding toward the driving sensing plate, and the driving sensing plate has at least one sensing hole and a second locking protrusion protruding toward the driven sensing plate, and the driving sensing plate. The drive shaft to which the plate is fixed is fitted into the groove formed in the rib of the driven sensing plate, and the rib is fitted with a spring so that both ends are Group a first locking projection is fixed to each of groups tile second obstacle, the sensing unit photosensor is a match is detected, the hole of the driven sensing plate and the driving sensing plate, characterized in that configured to detect the remaining amount of the toner by the mismatch.

The present invention for achieving the above object is a toner loading means for loading the toner in the developing device of the image forming apparatus, a stirring means for stirring the toner, a first fixed to the stirring means having one or more sensing holes A sensing hole supporting means, a driving means, a transmitting means for receiving a rotational force from the driving means, a second sensing hole supporting means fixed to the transmitting means, and having at least one sensing hole, and the first sensing hole supporting means. And a connecting means for allowing the second sensing hole supporting means to have a rotational central axis and having a different relative position according to the force applied to the stirring means, and installed outside the first sensing hole supporting means and the second sensing hole supporting means. And sensing means for detecting when the sensing holes of the first sensing hole supporting means and the second sensing hole supporting means coincide with each other.

Embodiments according to the present invention will now be described in detail with reference to the accompanying drawings.

2 is an exploded perspective view of the residual toner amount sensing device in the image forming apparatus of the present invention. 3 is a cross-sectional view of a developer in which an toner amount detection sensor is installed in the image forming apparatus. Referring to FIG. 2 and FIG. 3, the configuration of the residual toner amount sensing device of the image forming apparatus according to the present invention will be described.

The developer 21 has a developer housing 22 for storing toner, and the developer housing 22 has an agitator having a stirring blade 24 for agitating the toner 41 and transferring it to the developing roller 42 on one side. Install agitator (23) to be rotatable. The driven sensing plate 26 made of a disc fixed to the end of the agitator shaft 25 on one side of the developing unit housing 22 in which the stirrer 23 is installed has a first driven sensing centering on the rib 27 protruding outwardly in the center thereof. The first locking projection 29 protruding to one side with the second driven sensing hole 32 is formed at a predetermined distance from the hole 31 and the first driven sensing hole.

The drive sensing plate 34 made of a disc fixed to the outer drive shaft 32 forms first and second drive sensing holes 35 and 36 at spaced positions, respectively, and the second locking projection 37 protrudes inward. ) Is formed. The drive shaft 33 to which the drive sensing plate 34 is fixed is fitted into the central groove 28 formed in the rib 27 of the driven sensing plate 26, and the springs 30 are fitted into the ribs 27 so that both ends thereof are fitted. The stages are fixed to the second locking projections 37 of the driving sensing plate 34 and the first locking projections 29 of the driven sensing plate 26, respectively. The drive shaft 33 is a drive gear is assembled to the outer end is installed to rotate in the developer frame 40. The spring 30 installed in the rib 27 uses a torsion coil spring. The second locking projection 37 of the driving sensing plate 34 and the first locking projection 29 of the driven sensing plate 26 are determined by the resistance of the developer applied to the stirrer, the force of the spring 30, and the like. The relative position of the two sensing plates does not exceed a certain range. Therefore, the spring force is small compared with the resistance of the developer, so that the relative position may be excessively changed. This is not necessary.

A sensing unit 38 is provided on the outer side of the driven sensing plate 26 and the lower side of the driving sensing plate 34, and a light emitting device 39a which emits light with respect to an input of an electrical signal on one side of the sensing unit 38. ), And the other side of the sensing unit 38 corresponding thereto includes a light receiving element 39b that converts the light source into an electrical signal. Each of the light emitting element 39a and the light receiving element 39b is installed to be fixed at a position parallel to each other. One pair of photosensors 39 constituted by one light receiving element 39b located in parallel with one light emitting element 39a of one side of the sensing unit 38 is configured.

The photosensor 39 of the sensing unit 38 includes first and second driving sensing holes formed in the first and second driven sensing holes 31 and 32 and the driving sensing plate 34 of the driven sensing plate 26. 35) 36 are sensed so that they can be sensed to detect the remaining amount of toner.

The general configuration of the image forming apparatus is the same as that of the conventional first embodiment, but the present invention enables the residual amount of toner to be detected by using a photosensor without using a piezoelectric sensor to detect the residual amount of toner.

The operation and effects of the present invention configured as described above are as follows.

In the developing unit 21 using the electrophotographic developing method, the toner 41 is supplied to the stirrer 23 installed inside the developing unit housing 22 from the cover 43 so as to be rotated in the developing frame 40 in a filled state. When power is transmitted to the drive gear of the drive shaft 33, the drive sensing plate 34 fixed to the drive shaft 33 is rotated. The driving shaft 33 is inserted into the groove 28 formed in the central rib 27 by fixing the driven sensing plate 26 to the end of the agitator shaft 25 of the agitator 23 so as to be interlocked with the drive shaft 33. The rib 27 is fitted with a torsion coil spring, which is a power transmission spring 30, and one end thereof is fixed to the second catching protrusion 37 of the driving sensing plate 34, and the other end of the driven sensing plate 26. It is fixed to the first locking projection 29.

As the drive sensing plate 34 of the drive shaft 33 rotates, the spring 30 having one end fixed to the second catching protrusion 37 rotates while being elastic. The driven sensing plate 26 also transmits power through the spring 30 to rotate the stirrer shaft 25, which is the stirring means, and the toner filled inside the developer housing 22 by the stirring blades 24 of the stirrer 23. By stirring the 41, the toner is conveyed to the developing roller 42 on one side.

When the driving sensing plate 34 is rotated by the drive gear, the driven sensing plate 26 rotates while receiving the rotational force through the spring 30 to rotate the stirring blade 24 of the stirrer 23. At this time, the spring 30 is deformed by the resistance force applied to the stirring blade 24 of the stirrer 23 in proportion to the resistance force, and thus the driven sensing plate 26 and the driving sensing plate 34 are relative to each other in proportion to the resistance force. There is a position difference. This resistance is influenced by the area of the stirring blade 24 and the physical properties of the toner 41.

If the toner 41 is full in the developer housing 22, the resistance received by the stirring blade 24 becomes maximum. In other words, the relative position difference between the two sensing plates becomes maximum. When the elastic modulus of the spring 30 is weak as in this embodiment, the two engaging projections 29 and 37 provided on each sensing plate meet each other. This is shown in Figure 4c. By adjusting the modulus of elasticity of the spring 30, the relative position shown in FIG. 4C without the protrusion may be provided when the toner is filled in the developer housing 22. FIG. In this case, a spring having a larger elastic modulus than the spring used in the embodiment should be used. In the state as illustrated in FIG. 4C, all the sensing holes are shifted from each other, so that the light starting from the light emitting element 39a does not reach the light receiving element 39b of the sensing unit 38. As a result, as shown in FIG. 5, the sensing signal remains unchanged.

In the above state, the agitator 23 is continuously rotated by the drive shaft 33 to prevent the toner 41 from agglomerating and generates static electricity by friction, thereby transferring the toner 31 to the developing roller side. It is to be made.

As the image forming apparatus 21 operates as described above, when the toner 31 inside the developer housing 22 is gradually consumed and the toner amount falls below the reference value, the stirrer 23 is rotated and the torque applied to the stirring blade 24 is reduced. Therefore, when the driving sensing plate 34 rotates, the deformation of the spring 30 installed on the rib 27 of the driven sensing plate 26 is also reduced, so that the second locking projection 37 of the driving sensing plate 34 is driven sensing. The driven sensing plate 26 is interlocked without rotation to the position of the first locking projection 29 of the plate 26. At this time, only the first driving sensing hole 35 of the driving sensing plate 34 and the first driving sensing hole 31 of the driven sensing plate 26 are matched, and thus the driving sensing plate 33 is driven by the driving shaft 33 as shown in FIG. Since the 34 and the driven sensing plate 26 are rotated, the light of the light emitting element 39a installed in the sensing unit 38 is transmitted to the first driving sensing hole 35 and the driven sensing plate 26 of the driving sensing plate 34. Light is received by the light receiving element 39b of the sensing unit 38 through the first driven sensing hole 31. If the rotation continues in the above state, as shown in the low waveform diagram of FIG. 5, one sensing pulse appears in one rotation period T of the sensing plate.

If the developing unit 21 continues to operate as described above and the toner 41 inside the developing unit housing 22 is gradually consumed, the stirrer 23 rotates and there is no torque applied to the stirring blade 24. When the driving sensing plate 34 rotates, the driven sensing plate 26 also rotates without changing the relative position. In this case, since the first and second driven sensing holes 31 are rotated to match the first and second driven sensing holes 35 and 36 and the driven sensing plate 26 formed in the driving sensing plate 34, respectively. Likewise, when the sensing plate rotates once, two sensing pulses appear in one rotation period T of the sensing plate, as shown in the fifth waveform of the waveform of the fifth wave.

As described above, according to the amount of toner in the developer housing 22, the sensing plate floats from 0 to 2 times per one rotation so that the number of times of counting the toner in the developer housing can be detected.

Even if there is only one sensing hole in the sensing hole supporting means, the present invention is applicable. In this case, if all the sensing holes are circular, the sensing signal changes even if the relative position is slightly moved. Therefore, if one side of the sensing hole is long, the sensing range can be stable.

By applying the embodiment of the present invention, it is possible to make a plurality of sensing holes, and as the number of sensing holes increases, the toner amount of a plurality of stages can be sensed. This may be applied to the case where one sensing hole and two cases as in the present invention. The number of photosensors may also change with the number of sensing holes. When the plurality of photosensors are used, the waveform diagram of FIG. 5 is changed. In this case, different states can be recognized according to the changed waveform diagram. In addition, if you move closer between the sensing plates and increase the size of the sensing hole, you can use the micro switch instead of the photosensor. Various combinations of sensing signals may appear depending on the size and number of sensing holes, and the number of sensors. However, if the relative position difference between the two sensing plates is different depending on the amount of toner, the sensing signal may be different per one rotation of the sensing plate. Should know. Even in this embodiment, the toner amount can be distinguished only by changing the shape of the holes of the two sensing plates, but a sensing signal different from this embodiment is generated.

According to the present invention as described above to change the toner detection sensor of the piezoelectric sensor type to the photo sensor type in the developer housing in order to detect the amount of toner in the developer housing to supply the toner to the inside of the developer housing to configure the toner at a low price When there is a shortage, there is an advantage that the image density by the developing roller can be kept constant by supplying the toner inside the developer housing.

Claims (8)

A developing device of an image forming apparatus using an electrophotographic developing method, comprising: toner loading means for loading toner in a developing device, stirring means for stirring the toner inside the toner loading means, at least one sensing hole fixed to the stirring means; A first sensing hole supporting means having a driving force, a driving means for transmitting a driving force, a transmission means for receiving rotational force from the driving means, a second sensing hole supporting means fixed to the transmission means, and having at least one sensing hole; Connecting means for supporting the first sensing hole carrying means and the second sensing hole carrying means together with a rotational central axis and having a different relative position according to a force applied to the stirring means; 2 sensing means installed on the outside of the supporting means for sensing the sensing means for detecting when the sensing hole of the first and second sensing hole supporting means coincides Toner amount sensing device of the image forming apparatus, characterized in that. The toner amount sensing device of an image forming apparatus according to claim 1, wherein at least one sensing hole is formed in the first and second sensing hole bearing means. The toner amount sensing apparatus of claim 1, wherein one sensing hole and one sensing hole are formed on one side of the sensing hole supporting means, and two sensing holes are formed on one side. The toner amount sensing device of an image forming apparatus according to claim 1, wherein each of the first and second sensing hole supporting means has a locking projection. In the developing device of the image forming apparatus using an electrophotographic developing method, an agitator having a developing unit housing for storing toner on the developing unit housing of the image forming apparatus, and a stirring blade for transferring the toner to the developing roller on one side of the developing unit housing. A driven sensing plate fixed to an end of the stirrer shaft at one side of the developing unit housing in which the stirrer is installed, a driving sensing plate fixed to a driving shaft connected to the outside of the driven sensing plate, and a photo sensor outside the driven sensing plate and the driving sensing plate. The installed sensing unit and the driven sensing plate have at least one sensing hole and a first locking protrusion protruding toward the driving sensing plate, and the driving sensing plate has at least one sensing hole and a second locking protrusion protruding toward the driven sensing plate. The drive shaft to which the drive sensing plate is fixed is fitted into the groove formed in the rib of the driven sensing plate, and the rib has a spring The one end is fixed to the first catching protrusion and the other end is fixed to the second catching protrusion, respectively. The photosensor of the sensing unit is installed so that the sensing holes of the driven sensing plate and the driving sensing plate can be matched and detect the residual amount of toner by mismatch. Toner amount sensing device of the image forming apparatus. 6. The power transmission drive shaft of claim 5, wherein the drive transmission plate to which the drive sensing plate is fixed is fitted into a central groove formed in the rib of the driven sensing plate, and the spring is fitted into the rib so that both ends of the second engaging projection and the driven sensing plate of the driving sensing plate are fixed. The toner amount sensing device of the image forming apparatus, wherein the first sensing protrusion is fixed to each of the first locking protrusions, and the driving sensing plate and the driven sensing plate are interlocked. The toner amount sensing device of an image forming apparatus according to claim 6, wherein the spring is provided with a torsion coil spring so that the driving sensing plate and the driven sensing plate can be interlocked. The pair of photoelectric sensors of claim 5, wherein the sensing unit includes a light emitting device that emits light with respect to an input of an electrical signal on one side thereof, and a light receiving device that includes a light receiving device that converts an electric signal into an electrical signal on the other side thereof. Toner amount sensing device of the image forming apparatus, characterized in that the light emitting element and the light receiving element is installed so as to be fixed in parallel with each other.