JP2003021955A - Developer residual amount detecting device, process cartridge using the same and image forming device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer residual amount detecting device having a guide member whose incident surface for detecting light emitted by a light emitting member is secured to be wide in a space saving state so as to more accurately detect developer residual amount in a light transmission system, a process cartridge using the detecting device and an image forming device using the process cartridge. SOLUTION: By forming a stepped part on a light guide 31a and providing an auxiliary incident surface 31d in addition to the conventional incident surface 31c at the stepped part, the detecting light L emitted from a light emitting element 30a is made incident on the incident surfaces 31c and 31d, reflected on a reflection surface 31e and emitted from an exiting surface 31g, so that a light receiving element 30b can receive the light L emitted from the element 30a by sufficient light quantity to accurately detect toner residual amount without causing the loss of the light L.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus and a developer remaining amount detecting apparatus provided in a process cartridge detachably mountable to the main body thereof.

[0002]

2. Description of the Related Art An image forming apparatus such as a printer using an electrophotographic process uniformly charges a photosensitive drum, which is an image carrier, and forms a latent image by selectively exposing the photosensitive drum. , The latent image is visualized with toner as a developer,
Image recording is performed by transferring the toner image to a recording medium and further fixing the toner image to the recording medium by applying heat or pressure to the transferred toner image.

Such an apparatus is accompanied by toner replenishment and maintenance of various process means. As a means for facilitating the toner replenishment work and maintenance, the photosensitive drum, the charging means, the developing means, the cleaning means, etc. are provided in a frame body. Cartridges that have been put together have also been put to practical use.

The developing device for such a process cartridge is provided with a developer remaining amount detecting device for detecting the remaining amount of the stored developer. There are various types of developer remaining amount detecting devices, but as a cheaper and simpler structure, there is a light transmission type developer remaining amount detecting device. The light-transmissive developer remaining amount detection is a method in which detection light is passed through a container that stores the developer and the remaining amount of the developer stored in the container is detected based on the passage time of the detection light. .

A specific structure of the light transmission type developer remaining amount detecting device provided in the process cartridge 7 is shown in FIGS.
The detection light emitted from the light emitting member such as the light emitting element passes through the light guide 31a serving as the first guide member including the light transmitting member, and the light transmitting property provided in the developer container 25 is described. Is incident on the inside of the container from the first window member having.

Further, the detection light that has entered the developer container 25 passes through the second window member having the light transmitting property, which is also provided in the developer container 25, to the outside of the developer container 25, and further, the developer. The detection light emitted to the outside of the container 25 reaches a light receiving member such as a light receiving element via a light guide 31b which is a second guide member made of a light transmitting member, and is determined by the length of time that the light receiving member receives the detection light. It is configured to detect the remaining amount of the developer in the developer container 25.

On the other hand, the process cartridge 7 is attachable to and detachable from an image forming apparatus (not shown).
The process cartridge 7 is configured to be inserted and removed in the horizontal direction when the front door of the image forming apparatus is open.

The process cartridge 7 includes a guide rail portion 33 provided in the image forming apparatus shown in FIG.
The insertion guide portion 34 provided in the process cartridge 7 shown in FIG. 10 is configured to be attached / detached so that when the process cartridge 7 is inserted into the image forming apparatus, the guide is opened from the state in which the front door is opened. It is inserted along the rail portion 33 to the inner side of the image forming apparatus and stopped at the developing position of the process cartridge 7.

When the process cartridge 7 is detached from the image forming apparatus, the process cartridge 7 is removed from the image forming apparatus by pulling it out from the developing position along the guide rail portion 33 toward the front door. Be done.

[0010]

In order to accurately detect the remaining amount of the developer accommodated in the developer container 25 by the light transmission type developer remaining amount detection, it is necessary to secure a larger amount of light. . Examples of the method include increasing the light amount of the detection light emitted from the light emitting member and widening the incident surface of the light guide 31a serving as the first guide member that receives the detection light emitted from the light emitting member.

In particular, widening the incident surface of the light guide 31a is effective as a means for improving the accuracy of the light transmission type developer residual amount detection with a cheaper and simpler structure, but the light guide 31a is incident. When the surface is widened, the light guide 31
As a becomes large, as a result, there arises a problem that it cannot fit in a limited space in the main body of the image forming apparatus, and that it interferes with other parts of the process cartridge 7.

That is, as shown in FIGS. 10 and 11, when the size of the light guide 31a is increased in order to improve the accuracy of the developer remaining amount detecting device, the protrusion F of the light guide 31a protrudes from the insertion guide portion 34. I will end up.

With such a structure, when the process cartridge 7 is arranged at the developing position in the image forming apparatus, the light guide 31a interferes with other peripheral parts as shown in FIG. 12 (a). However, as shown in FIG. 12B, the process cartridge 7 is not installed in the image forming apparatus.
There is a problem that the protruding portion F of the light guide 31a interferes with the guide rail portion 33 when inserting and removing.

However, if the light guide 31a is downsized in order to avoid the interference between the light guide 31a and the guide rail portion 33, the incident surface also becomes small, so that the detection light incident on the light guide 31a can be sufficiently received. As a result, the remaining amount of developer cannot be accurately detected.

Further, if the developer remaining amount is not accurately detected, if the image is formed in a state where it is detected that the developer still remains in the developer container 25, a blank image of the printed image is generated. If the image forming apparatus continues to print while the image forming apparatus is awakened or the developer is empty, the image forming apparatus may be damaged due to torque increase or the like.

The present invention solves the above-mentioned problems.
The purpose is to achieve a more accurate light transmission type developer residual amount detection, which is space-saving and has a developer residual member having a guide member having a wide incident surface for the detection light emitted by the light emitting member. An amount detection device, a process cartridge using the same, and an image forming device using the same are provided.

[0017]

A developer remaining amount detecting device according to the present invention for achieving the above object comprises a container capable of accommodating a developer, a first window member provided in the container, A second window member provided in the container, a light emitting member, a first guide member that guides light emitted from the light emitting member to the first window member, a light receiving member, and the first A second guide member that guides light that has entered from the window member and that has passed through the inside of the container to the light receiving member from the second window member, the first guide member and the second guide. At least one of each of the entrance and exit sections of the member,
It is characterized in that a plurality of surfaces substantially perpendicular to the light passing through the first and second guide members are provided respectively.

That is, the first and second guide members are appropriately stepped so that the incident surface or the emission surface for the detection light emitted by the light emitting members provided on the end faces of the first and second guide members can be changed. The stepped portion is provided with an auxiliary entrance surface or exit surface.

Since the present invention is configured as described above, the first and second guide members are appropriately stepped so as to ensure a sufficiently large incident surface for the light emitting member and the first and second guide members. It is possible to save the space, and it is possible to avoid the interference between the light guide 31a serving as the first guide member and the guide rail portion 33 as shown in FIG. It is possible to house the developer remaining amount detecting device in a limited space in the main body of the device.

Further, the detection light emitted from the light-emitting member can be obtained by appropriately forming the first and second guide members in a stepped shape so that the first and second guide members have a plurality of incident surfaces or emission surfaces. Can be reliably received, and as a result, the remaining amount of developer can be detected with higher accuracy.

Another developer remaining amount detecting apparatus according to the present invention is a container capable of accommodating a developer, a first window member provided in the container, and a second window member provided in the container. Inside the container, a window member, a light emitting member, a first guide member that guides light emitted from the light emitting member to the first window member, a light receiving member, and the light is incident from the first window member. A second guide member for guiding the light passing through the second window member to the light receiving member, wherein the first guide member and / or the second guide member is provided at one end of each of the first guide member and / or the second guide member. A plurality of surfaces having a light entrance surface and a light exit surface at the other end, and substantially perpendicular to the light passing through the first and second guide members between the entrance surface and the exit surface. It is characterized by being provided.

That is, a concave portion is provided between the incident surface and the outgoing surface of the first and second guide members, and an auxiliary incident surface and an outgoing surface are provided in the concave portion.

According to the above structure, the first and second guide members are appropriately provided with the recesses, so that the incident surface for the light emitting member is sufficiently wide and space saving of the first and second guide members is realized. As a result, it is possible to avoid the interference between the light guide 31a, which is the first guide member shown in FIG. 12B, and the guide rail portion 33, and further, the limited space in the image forming apparatus main body. It is possible to house the developer remaining amount detecting device therein.

Further, by providing a recess appropriately between the incident surface and the exit surface of the first and second guide members, the detection light taken in from the incident surfaces of the first and second guide members is temporarily By escaping from the auxiliary emission surface, and further taking in from the auxiliary incidence surface, it is possible to receive a sufficient amount of light for performing highly accurate residual amount detection of the developer without loss of detection light. It becomes possible to detect the remaining amount of the developer with higher accuracy.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a developer remaining amount detecting apparatus, a process cartridge using the same and an image forming apparatus using the same will be specifically described with reference to the drawings. FIG. 1 is a cross-sectional explanatory view showing the configuration of an image forming apparatus in which a process cartridge equipped with a developer remaining amount detecting device according to the present invention is mounted, and FIG. 2 is a front door of the image forming apparatus opened to attach and detach the process cartridge. It is a figure which shows a mode that it does.

FIG. 3 is a perspective explanatory view showing the structure of an engaging portion provided on the image forming apparatus side for mounting the process cartridge, and FIG. 4 is provided on the process cartridge side for mounting on the image forming apparatus. 5 is a schematic perspective view showing the configuration of the developer remaining amount detecting device according to the present invention, and FIG. 6 is equipped with the developer remaining amount detecting device according to the present invention. FIG. 7 is a cross-sectional explanatory view showing the structure of the process cartridge, and FIG. 7 is a view showing the mounting / demounting structure of the image forming apparatus and the process cartridge.

Further, FIG. 8A is a perspective explanatory view showing the structure of the first guide member of the first embodiment of the developer remaining amount detecting apparatus according to the present invention, and FIG. 8B is related to the present invention. FIG. 3 is a cross-sectional explanatory view showing a configuration of a first guide member of the first embodiment of the developer remaining amount detecting device.

Here, the image forming apparatus A according to the present invention is an electrophotographic image forming apparatus which forms an image on a recording medium using an electrophotographic image forming system. Examples of the electrophotographic image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (for example, laser beam printer, LED printer, etc.), a facsimile machine, a word processor, etc.

The process cartridge 7 is a cartridge in which the charging means, the developing means or the cleaning means and the electrophotographic photosensitive drum 1 are integrally formed, and the cartridge can be attached to and detached from the main body of the image forming apparatus A. Is.

Further, at least one of the charging means, the developing means, and the cleaning means and the electrophotographic photosensitive drum 1 are integrally made into a cartridge which can be attached to and detached from the main body of the image forming apparatus A. Further, it means that at least the developing means and the electrophotographic photosensitive drum 1 are integrally made into a cartridge so that it can be attached to and detached from the main body of the image forming apparatus A.

First, the overall structure of the image forming apparatus A in which the process cartridge 7 having the developer remaining amount detecting device according to the present invention is mounted will be outlined with reference to FIG. An image forming apparatus A shown in FIG. 1 is a full-color laser beam printer which is one mode of a multicolor image forming apparatus, and includes four photosensitive drums 1a, 1a arranged in parallel in the vertical direction of the apparatus body.
b, 1c, 1d.

The photosensitive drum 1 is rotationally driven in the counterclockwise direction in FIG. 1 by a driving means (not shown). Around the photosensitive drum 1, charging devices 2a, 2 for uniformly charging the surface of the photosensitive drum 1 in order according to the rotation direction thereof.
b, 2c, 2d, scanner units 3a, 3b, 3c, 3d that irradiate a laser beam based on image information to form an electrostatic latent image on the uniformly charged photosensitive drum 1.
Developing devices 4a, 4b, 4c, 4d for developing toner images by attaching toner T as a developer to the electrostatic latent image formed on the photoconductor drum 1, and the toner image on the photoconductor drum 1 as a recording medium. And a cleaning device 6a, 6b, 6c, 6 for removing the transfer residual toner T remaining on the surface of the photosensitive drum 1 after the transfer.
d and the like are provided.

In this embodiment, the photosensitive drum 1, the charging device 2, the developing device 4, and the cleaning device 6 are integrally formed into a cartridge to form a process cartridge 7.

The photoconductor drum 1 is, for example, an organic photoconductor layer (OPC photoconductor) on the outer peripheral surface of an aluminum cylinder having a diameter of 30 mm.
Is applied. Both ends of the photosensitive drum 1 are rotatably supported by support members, and a driving force from a drive motor (not shown) is transmitted to one end of the photosensitive drum 1 to rotate it in the counterclockwise direction in FIG. Driven.

As the charging device 2, a contact charging type device can be used. The charging member is a conductive roller formed in the shape of a roller. The roller is brought into contact with the surface of the photosensitive drum 1, and a charging bias voltage is applied to the roller to make the surface of the photosensitive drum 1 uniform. It is to be charged.

The scanner unit 3 is arranged substantially in the horizontal direction of the photosensitive drum 1, and a polygon mirror 9a, in which image light corresponding to an image signal is rotated at high speed by a scanner motor (not shown) by a laser diode (not shown).
Irradiation is performed on 9b, 9c, and 9d.

The image light reflected by the polygon mirror 9 is selectively exposed on the surface of the charged photosensitive drum 1 through the imaging lenses 10a, 10b, 10c and 10d to form an electrostatic latent image. is doing.

The developing devices 4a, 4b, 4c and 4d respectively contain developer containers 25a, 25b and 25 containing toners T of yellow, magenta, cyan and black, respectively, which serve as developers.
It is configured with c and 25d.

Then, all the photosensitive drums 1a, 1b,
An electrostatic transfer belt 11 is disposed so as to face and contact 1c and 1d, and to circulate. The electrostatic transfer belt 11 is 10
It is composed of a film-like member with a thickness of approximately 150 μm that has a volume resistivity of ¹¹ Ω · cm to 10 ¹⁴ Ω · cm.

The electrostatic transfer belt 11 is supported by rollers on four axes in the vertical direction of the main body of the apparatus, and electrostatically attracts the transfer material S to the outer peripheral surface on the left side in FIG.
Circularly move to contact. As a result, the transfer material S
Is conveyed to the transfer position by the electrostatic transfer belt 11, and the toner image on the photosensitive drum 1 is transferred.

Abutting on the inside of the electrostatic transfer belt 11,
Transfer rollers 12a, 12b, 12c, 12d are arranged in parallel at positions facing the respective photosensitive drums 1a, 1b, 1c, 1d.
A positive charge is transferred from these transfer rollers 12 to the electrostatic transfer belt.
The negative toner image on the photosensitive drum 1 is transferred to the transfer material S which is applied to the transfer material S via 11 and is in contact with the photosensitive material drum 1 by the electric field due to the electric charges.

The electrostatic transfer belt 11 is a belt having a peripheral length of about 700 mm and a thickness of 150 μm, and includes a driving roller 13 and a driven roller.
Four rollers 14a, 14b and a tension roller 15 are stretched around and rotate in the direction of the arrow in FIG. This allows
The toner image formed on the photosensitive drum 1 is transferred while the above-mentioned electrostatic transfer belt 11 circulates and the transfer material S is conveyed from the driven roller 14a side to the drive roller 13 side.

The feeding section 16 feeds the transfer material S to the image forming section in which the photosensitive drum 1 is arranged, and a plurality of transfer materials S are stored in the feeding cassette 17. At the time of image formation, the feed roller 18 and the registration roller pair 19 which are half-moon rollers are driven and rotated in response to the image forming operation to separate and feed the transfer materials S in the feeding cassette 17 one by one, and at the end of the transfer material S. Is stopped by temporarily hitting the registration roller pair 19 to form a loop, and then fed to the electrostatic transfer belt 11 by the registration roller pair 19 in synchronization with the rotation of the electrostatic transfer belt 11 and the image writing position. Go.

The fixing section 20 is for fixing the toner images of a plurality of colors transferred to the transfer material S, and the heating roller 21a which is rotationally driven and the heating roller 21a which is pressed against the heating roller 21a to apply heat and pressure to the transfer material S. The pressure roller 21b.

That is, the transfer material S onto which the toner image on the photosensitive drum 1 has been transferred is heated by the heating roller 21 when passing through the fixing section 20.
It is conveyed by a fixing roller pair composed of a and a pressure roller 21b, and heat and pressure are applied by the fixing roller pair. As a result, the toner images of a plurality of colors are fixed on the surface of the transfer material S.

In the image forming operation, the process cartridges 7a, 7b, 7c and 7d are sequentially driven in accordance with the print timing, and the respective photosensitive drums 1a, 1b, 1c and 1d are driven in accordance with the driving. Is rotated counterclockwise. And each process cartridge 7
The scanner units 3 corresponding to are sequentially driven.

By this driving, the charging roller 2 applies a uniform charge to the peripheral surface of the photosensitive drum 1, and the scanner unit 3
Exposes the peripheral surface of the photosensitive drum 1 in accordance with an image signal to form an electrostatic latent image on the peripheral surface of the photosensitive drum 1. The developing roller 27 in the developing device 4 transfers the toner T to the low potential portion of the electrostatic latent image to form (develop) a toner image on the peripheral surface of the photosensitive drum 1.

At the timing when the leading edge of the toner image on the peripheral surface of the most upstream photosensitive drum 1 is rotatably conveyed to the opposite point to the electrostatic transfer belt 11, the print start position of the transfer material S is at the opposite point. The registration roller pair 19 starts to rotate so as to match, and the transfer material S is fed to the electrostatic transfer belt 11.

The transfer material S is sandwiched between the electrostatic attraction roller 22 and the electrostatic transfer belt 11 so that the electrostatic transfer belt 11 is held.
Of the dielectric material of the transfer material S which is a dielectric and the dielectric layer of the electrostatic transfer belt 11 by applying a voltage between the electrostatic transfer belt 11 and the electrostatic attraction roller 22 while being pressed against the outer periphery of the electrostatic transfer belt 11. ,
The transfer material S is configured to be electrostatically attracted to the outer circumference of the electrostatic transfer belt 11. As a result, the transfer material S is stably attracted to the electrostatic transfer belt 11 and is conveyed to the most downstream transfer unit.

While being conveyed in this manner, the transfer material S sequentially transfers the toner image on each photosensitive drum 1 by the electric field formed between each photosensitive drum 1 and the transfer roller 12. The transfer material S to which the four color toner images have been transferred is separated from the electrostatic transfer belt 11 by the curvature of the driving roller 13,
It is carried into the fixing unit 20. The transfer material S is heat-fixed with the toner image by the fixing unit 20, and is then discharged from the discharge unit 24 to the outside of the main body by the discharge roller pair 23 with the image surface facing down.

Next, a method for attaching / detaching the process cartridge 7 to / from the main body of the image forming apparatus A will be specifically described.
As shown in FIG. 2, the process cartridge 7 is attachable / detachable to / from the image forming apparatus A. At this time, the process cartridge 7 is inserted / removed in the horizontal direction with the front door 32 of the image forming apparatus A opened. It is composed.

Further, as shown in FIGS. 3 and 4, in the image forming apparatus A, the process cartridge 7 includes a guide rail portion 33 provided in the image forming apparatus A and an insertion provided in the process cartridge 7. When the guide portion 34 is engaged, it is configured to be attached and detached as shown in FIG. 7. When the process cartridge 7 is inserted into the image forming apparatus A, the guide rail portion is opened from the state where the front door 32 is opened. 33
Process cartridge 7
Stop at the developing position.

When the process cartridge 7 is detached from the image forming apparatus A, the guide rail portion 33 is moved from the developing position.
The process cartridge 7 is taken out of the image forming apparatus A by being pulled out toward the front door 32 side along.

Next, the structure of the first embodiment of the light transmitting type developer remaining amount detecting device, which is a characteristic part of the present invention, will be described with reference to FIGS. Each process cartridge 7 is equipped with a light transmission type developer residual amount detecting device which will be described in detail later.

As shown in FIGS. 3 and 5, a light emitting element 30a which serves as a light emitting member and a light receiving element 30b which serves as a light receiving member are provided on the image forming apparatus A side, and as shown in FIG.
On the process cartridge 7 side, a light transmitting window 26a serving as a first window member provided in the developer container 25, a light transmitting window 26b serving as a second window member, and detection light L emitted from the light emitting element 30a. And a light guide 31a serving as a first guide member that guides the light to a light transmitting window 26a serving as a first window member, and the light transmitting window 26a.
The detection light L that has been incident from a and has passed through the interior of the developer container 25 is received by the light receiving element 30 from the light transmission window 26b that serves as a second window member.
The light guide 31b serving as a second guide member to reach b.
And are provided.

Light transmitting windows 26a, 26b and light guide 31
Reference characters a and 31b are made of a transparent material such as acrylic having a light transmitting property.

In the developer container 25 of the process cartridge 7 containing the toner T as a developer, a light transmitting window 26a serving as a first window member is formed on the bottom surface and the top surface of the developer container 25, and a second window member. The light transmitting windows 26b are provided respectively, and the light transmitting windows 26a and 26b are formed in a convex shape toward the inside of the developer container 25 as shown in FIG.

Incidentally, the positional relationship between the light transmitting windows 26a and 26b may be opposite to that of the present embodiment. In that case, the positional relationship between the light emitting element 30a and the light receiving element 30b is also oppositely arranged. The irradiation direction of the light L is from the upper direction to the lower direction in FIG.

A first stirring member 28a and a second stirring member 28b are provided in the developer container 25 from the side close to the developing roller 27, and are supplied by rotating the respective stirring members 28a, 28b. The toner T is conveyed to the roller 29. The first agitating member 28a is used for transmitting the toner T and is also used for the light transmitting window 26.
The first agitating member 28 that also serves as a cleaning member for removing the toner T adhering to the inside of a and 26b and has flexibility.
As a rotates, the toner T adhering to the inside of the light transmitting windows 26a and 26b is wiped off and cleaned.

As shown in FIG. 5, a light emitting element 30a and a light receiving element 30b provided on the side of the main body of the image forming apparatus A are arranged on the side surface of the developer container 25, and the detection light emitted from the light emitting element 30a is detected. L passes through the light guide 31a serving as a first guide member arranged in the longitudinal direction of the developer container 25 and enters the developer container 25 through the light transmission window 26a.

Then, the detection light L incident on the inside of the developer container 25 passes through the light transmitting window 26b to the outside of the developer container 25. The detection light L that has passed to the outside of the developer container 25 reaches the light receiving element 30b via the light guide 31b, which is a second guide member that is also arranged in the longitudinal direction of the developer container 25, and the light is received there. How long the element 30b is, the detection light L
The remaining amount of the toner T stored in the developer container 25 is detected depending on whether or not the light is received.

With such a structure, the light receiving element 30
It is possible to sequentially detect the remaining amount of the toner T stored in the developer container 25 by the change in the length of time that the b receives the detection light L, and the toner T is stored in the developer container 25. It is designed to inform the user that there is about to disappear.

Here, in order to improve the accuracy of the light transmission type developer remaining amount detecting method, the light amount of the detection light L is increased and the light receiving element is increased.
It is necessary to ensure that 30b can receive the light passing through the inside of the developer container 25. For that purpose, it is necessary to increase the light amount of the light emitting element 30a and to widen the incident surface and the emitting surface of the light guide 31a and the light guide 31b.

In particular, the incident surface of the light guide 31a needs to be as wide as possible in the sense that the detection light L first emitted by the light emitting element 30a is secured without loss. However, widening the incident surface in the light guide 31a leads to an increase in the size of the light guide 31a as a component, and as a result, as described above with reference to FIGS. 10 and 11, the light guide 31a is used as an insertion guide for the process cartridge 7. Part 34
Stick out from.

With such a structure, as described above with reference to FIG. 12 (a), when the process cartridge 7 is arranged at the developing position in the image forming apparatus A, the light guide 31a is provided in other peripheral areas. Although it does not interfere with the parts,
As shown in (b), when the process cartridge 7 is inserted into or removed from the image forming apparatus A, the light guide 31a interferes with the guide rail portion 33 at the protrusion F.

However, if the light guide 31a is downsized so as not to interfere with the guide rail portion 33 of the main body of the image forming apparatus A, a sufficient amount of the detection light L cannot enter the developer container 25, resulting in As a result, the accuracy of the remaining toner amount detection decreases.

Therefore, in this embodiment, as shown in FIG. 8A, the light guide 31a has two stepped portions (3).
Have two steps). With such a shape, the guide rail portion 33 of the main body of the image forming apparatus A, which would otherwise interfere, is avoided, and as shown in FIG. By providing the auxiliary incident surface 31d at two positions on both sides, the detection light L emitted from the light emitting element 30a enters from the incident surfaces 31c and 31d, is reflected by the reflecting surface 31e, and is emitted from the emitting surface 31g. This allows the light emitting element 30
The detection light L emitted from a is configured so that the light receiving element 30b can receive a sufficient amount of light for detecting the remaining toner amount with high accuracy without loss.

In the present embodiment, a plurality of incident surfaces 31c and 31d that are substantially perpendicular to the detection light L passing through the light guide 31a are provided at the incident portion of the light guide 31a serving as the first guide member. I explained an example, but the light guide
The detection light L that passes through the light guide 31a to the emission portion of 31a
It is also possible to provide a plurality of emission surfaces that are substantially perpendicular to. Furthermore, a plurality of incident surfaces or emission surfaces that are substantially perpendicular to the detection light L passing through the light guide 31b may be provided at the incident portion or the emission portion of the light guide 31b that serves as the second guide member.

Further, the entrance surface and the exit surface of the light guides 31a and 31b are formed to have an angle range of 45 ° ± 15 ° with respect to the detection light L passing through the light guides 31a and 31b.

Next, the configuration of the second embodiment of the developer remaining amount detecting device according to the present invention will be described with reference to FIG. Figure 9
FIG. 9A is a perspective explanatory view showing a configuration of a first guide member of a second embodiment of the developer remaining amount detecting device according to the present invention, and FIG.
FIG. 6B is a sectional explanatory view showing the configuration of the first guide member of the second embodiment of the developer remaining amount detecting device according to the present invention.

In this embodiment, the light guide 31a serving as the first guide member has the incident surface 31c of the detection light L at one end and the exit surface 31g at the other end, and the entrance surface 31c and the exit surface 31g.
It has a recess between and.

With such a shape, the interference with the guide rail portion 33 of the main body of the image forming apparatus A, which originally should have interfered, is avoided, and as shown in FIG.
By providing the auxiliary incident surface 31d and the exit surface 31f in the recess in addition to the entrance surface 31c and the exit surface 31g at the end of a, the detection light L captured by the light guide 31c from the entrance surface 31c is temporarily
It escapes from the auxiliary emission surface 31f, and again the auxiliary incident surface.
By taking in from 31d, the detection light L emitted from the light emitting element 30a is incident from the incident surface 31c, part of which is emitted from the emission surface 31f, is further incident from the incident surface 31d, and is reflected by the reflection surface 31e and is emitted from the emission surface 31g. Is emitted from. This allows the light emitting element 30
The detection light L emitted from a is configured so that the light receiving element 30b can receive a sufficient amount of light for detecting the remaining toner amount with high accuracy without loss.

In the present embodiment, an emission surface 31f, which is substantially perpendicular to the detection light L passing through the light guide 31a, is provided between the incident surface 31c and the emission surface 31g of the light guide 31a serving as the first guide member. Also, an example of the case where a plurality of incident surfaces 31d is provided has been described, but the detection light L passing through the light guide 31b is substantially between the incident surface and the emission surface of the light guide 31b serving as the second guide member. A plurality of vertical emission surfaces and incidence surfaces may be provided.

Further, a plurality of recesses are formed between the incident surface of the detection light L provided at one end of the light guides 31a and 31b serving as the first and second guide members and the emission surface provided at the other end. The light guides 31a serving as the first and second guide members,
The light guides 31a, 31 are provided between the incident surface and the exit surface of 31b.
It may be configured by further providing a plurality of emission surfaces and incidence surfaces that are substantially perpendicular to the detection light L passing through b.

Further, the entrance surface and the exit surface of the light guides 31a and 31b are constructed to have an angle range of 45 ° ± 15 ° with respect to the detection light L passing through the light guides 31a and 31b.

Although a laser beam printer is illustrated as the image forming apparatus A in each of the above-mentioned embodiments, the present invention is not limited to this. For example, an image forming apparatus such as a copying machine, a facsimile machine or a word processor can be used. Needless to say, it is possible to use, and there is no need to limit to the configuration in which the developer remaining amount detecting device according to the present invention is provided in the process cartridge 7 exemplified in each of the above-mentioned embodiments, and for example, a process cartridge system is used. It is of course possible to use the developer remaining amount detecting device according to the present invention in an image forming apparatus of a non-type.

[0077]

Since the present invention has the above-mentioned structure and operation, it is possible to surely ensure the space saving and the high accuracy in the developer remaining amount detecting device with a simple structure. .

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing a configuration of an image forming apparatus in which a process cartridge including a developer remaining amount detecting device according to the present invention is mounted.

FIG. 2 is a diagram illustrating a state in which a front door of the image forming apparatus is opened and a process cartridge is attached and detached.

FIG. 3 is a perspective explanatory view showing a configuration of an engaging portion provided on the image forming apparatus side for mounting the process cartridge.

FIG. 4 is a bottom perspective view showing a configuration of an engaging portion provided on the process cartridge side for mounting on the image forming apparatus.

FIG. 5 is a schematic perspective view showing the configuration of a developer remaining amount detecting device according to the present invention.

FIG. 6 is a cross-sectional explanatory diagram showing a configuration of a process cartridge including the developer remaining amount detecting device according to the present invention.

FIG. 7 is a diagram showing a detachable structure of the image forming apparatus and the process cartridge.

FIG. 8A is a perspective explanatory view showing a configuration of a first guide member of the first embodiment of the developer remaining amount detecting apparatus according to the present invention, and FIG. 8B is a developer remaining amount detecting according to the present invention. It is a section explanatory view showing composition of the 1st guide member of a 1st embodiment of a device.

9A is a perspective explanatory view showing a configuration of a first guide member of a second embodiment of the developer remaining amount detecting apparatus according to the present invention, and FIG. 9B is a developer remaining amount detecting according to the present invention. It is sectional explanatory drawing which shows the structure of the 1st guide member of 2nd Embodiment of an apparatus.

FIG. 10 is a diagram illustrating a problem of a conventional example.

FIG. 11 is a diagram illustrating a problem of a conventional example.

FIG. 12 is a diagram illustrating a problem of a conventional example.

[Explanation of symbols]

A ... Image forming apparatus, S ... Transfer material, T ... Toner, L ... Detecting light, 1, 1a-1d ... Photoreceptor drum, 2, 2a-2d ...
Charging device, 3, 3a to 3d ... Scanner unit, 4, 4
a to 4d ... Developing device, 5 ... Electrostatic transfer device, 6, 6a to 6
d ... Cleaning device, 7, 7a to 7d ... Process cartridge, 9, 9a to 9d ... Polygon mirror, 10a to 10
d ... Imaging lens, 11 ... Electrostatic transfer belt, 12, 12a to 12d
... transfer roller, 13 ... driving roller, 14a, 14b ... driven roller, 15 ... tension roller, 16 ... feeding section, 17 ... feeding cassette, 18 ... feeding roller, 19 ... registration roller pair, 20 ... fixing section, 21a ... Heating roller, 21b ... Pressure roller, 22 ... Electrostatic attraction roller, 23 ... Ejection roller pair, 24 ... Ejection section, 25, 25a
-25d ... Developer container, 26a, 26b ... Light transmitting window, 27 ... Developing roller, 28a, 28b ... First and second stirring members, 29 ... Supply roller, 30a ... Light emitting element, 30b ... Light receiving element, 31a, 31b
... Light guide, 31c, 31d ... Incident surface, 31e ... Reflective surface,
31f, 31g ... Emitting surface, 32 ... Front door, 33 ... Guide rail part,
34 ... Insertion guide

Continued front page    (72) Inventor Tatsuo Kawai             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F term (reference) 2H077 AA12 DA15 DA34 DA64 DA65                       FA16

Claims (11)

[Claims] 1. A container capable of accommodating a developer, a first window member provided in the container, a second window member provided in the container, a light emitting member, and a light emitted from the light emitting member. A first guide member that guides light to the first window member, a light-receiving member, and light that is incident from the first window member and has passed through the inside of the container from the second window member. A second guide member that reaches the light receiving member, and the first guide member and the second guide member each have at least one of the entrance portion and the exit portion, respectively. A developer residual amount detecting device, characterized in that a plurality of surfaces substantially perpendicular to the light passing through the second guide member are provided. 2. A container capable of containing a developer, a first window member provided in the container, a second window member provided in the container, a light emitting member, and a light emitted from the light emitting member. A first guide member that guides light to the first window member, a light-receiving member, and light that is incident from the first window member and has passed through the inside of the container from the second window member. A second guide member reaching the light receiving member, wherein the first guide member and / or the second guide member has a light incident surface at one end and emits light at the other end. A developer remaining amount detection having a surface and a plurality of surfaces substantially perpendicular to the light passing through the first and second guide members are provided between the incident surface and the emission surface. apparatus. 3. The entrance surface and / or the exit surface of the first guide member and / or the second guide member are at an angle of ± 45 ° with respect to light passing through the first and second guide members.
The developer remaining amount detecting device according to claim 1 or 2, wherein the device is formed with an angle range of 15 °. 4. The first window member, the second window member,
At least 1 of the said 1st guide member and the said 2nd guide member consists of transparent members, such as acryl which has a light transmittance, characterized by the above-mentioned.
Item 5. The residual developer amount detecting device according to item. 5. The first window member and the second window member are provided in a positional relationship of the top surface and the bottom surface of the container, respectively, or vice versa, respectively. Item 5. The residual developer amount detecting device according to item. 6. The developer remaining amount detecting device according to claim 1, wherein the light emitting member and the light receiving member are provided on a side surface of the container. 7. The developer according to claim 1, wherein the first window member and the second window member are convex toward the inside of the container. Remaining amount detection device. 8. The container according to claim 1, further comprising a cleaning member for removing a developer adhering to the inside of the first window member and the second window member. 2. The residual developer amount detecting device according to item 1. 9. The residual developer amount detecting device according to claim 1, wherein the cleaning member has flexibility. 10. A process cartridge detachably mountable to an image forming apparatus, comprising the developer remaining amount detecting device according to claim 1. 11. An image forming apparatus comprising the developer remaining amount detecting device according to claim 1 or the process cartridge according to claim 10.