JP2005099458A - Developer residual detector and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact and high accuracy developer residual amount detector, without having to provide a member for cleaning a light guide member, and to provide an image forming apparatus provided with the same. <P>SOLUTION: The rod-like light guide member 3, penetrating the inside of a toner container 6, is provided in a toner residual amount detection part 10. A light-emitting element 1 is provided on one end of the light guide member 3, and a light-receiving element 2 is provided on the other end respectively. The light guide member 3 is covered with a tube 8 having flexibility. Thus, toner 5 does not adhere to the surface of the light guide member 3. In addition, the light guide member 3 is positioned in the inside of the toner container 6, and a light leak part 4 for leaking out light in the inside of the light guide member 3 to the outside is provided. When the light in the inside of the light guide member 3 reaches the light leak part 4, almost all of the light is reflected in the inside of the light guide member 3, when the residual amount of the toner 5 is large. When the residual amount of the toner 5 is small, almost all of it leaks to the outside. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a developer remaining amount detection device capable of detecting a remaining amount of developer and an image forming apparatus including the same. More specifically, the present invention relates to a developer remaining amount detection device that detects the remaining amount of developer by transmitting and receiving light and an image forming apparatus including the same.

  2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus, a developer remaining amount detection device that detects the remaining amount of toner by using light is known. As such a developer remaining amount detecting device, for example, there is a toner remaining amount detecting device disclosed in Patent Document 1. In this toner remaining amount detecting device, a light guide member on the light emitting side and a light guide member on the light receiving side are respectively provided in the toner container. And it arrange | positions so that the edge part of each light guide member may oppose.

In this toner remaining amount detection device, light from the light emitting member is guided into the toner container through the light guide member on the light emitting side. The light guided into the toner container is emitted from the end of the light guide member on the light emission side. When the amount of toner in the toner container is small, the emitted light is guided to the end of the light guide member on the light receiving side. The light guided to the end portion of the light guide member on the light receiving side enters the light receiving member via the light guide member on the light receiving side. On the other hand, when there is a lot of toner in the toner container, the toner becomes a barrier on the light path, so that light emitted from the light guide member on the light emitting side does not enter the light guide member on the light receiving side. Due to this difference, it is said that the remaining amount of toner can be evaluated by analyzing the detection signal of the light receiving member.
JP 2002-287477 A

  However, the above-described conventional developer remaining amount detection device has the following problems. That is, in the conventional developer remaining amount detection device, it is necessary to prevent the toner from adhering to the end portion (opposing portion) of the opposing light guide member. Therefore, a cleaning member that cleans the facing portion of the light guide member is provided. However, the provision of this cleaning member hinders downsizing of the entire apparatus and increases the cost.

  Moreover, since it is necessary to make the edge part of both light guide members oppose, high assembly precision is requested | required. In addition, it is necessary to strengthen the light guide member itself so that positional displacement does not occur between the two. Therefore, the manufacturing cost for these measures is also a factor of cost increase. In addition, if the displacement occurs after shipment, the detection performance is inevitably degraded.

  The present invention has been made in order to solve the problems of the conventional developer remaining amount detection device and the image forming apparatus including the same. That is, an object of the present invention is to provide a compact and highly accurate developer remaining amount detection device and an image forming apparatus including the same without providing a member for cleaning the light guide member.

  The developer remaining amount detecting device for solving this problem is a developer remaining amount detecting device that detects the remaining amount of developer in the developer reservoir, and detects the light incident on one end. A member guided to the other end, wherein at least a part of the light guide path is located in the developer reservoir, a light emitting means installed at one end of the light guide, A light receiving means installed at the other end of the optical member; and a tubular member that is flexible and is located in the developer reservoir and into which the light guiding member is inserted. Is provided with a light leakage part at a position in the developer reservoir for leaking light emitted from the light emitting means and propagating through the light guide member to the outside of the light guide member.

  In the developer remaining amount detection device of the present invention, at least a part of the light guide path has a light guide member located in the developer reservoir. The state where at least a part of the light guide path is located in the developer reservoir corresponds to, for example, a state where the light guide member penetrates the developer reservoir. Moreover, the whole may be inserted into the developer reservoir. In either case, the light emitting means is provided at one end and the light receiving means is provided at the other end, and the light guide member communicates from the light emitting means to the light receiving means. Therefore, the light incident on one end of the light guide member is guided to the other end. Furthermore, a light leakage part is provided on the surface of the light guide member to leak light that has propagated through the light guide member to the outside of the light guide member. Further, the light guide member including the light leakage portion is inserted into a flexible tubular member. Therefore, the developer does not adhere to the light guide member.

  In this developer remaining amount detecting device, the light receiving means receives the light from the light emitting means and analyzes the detection signal from the light receiving means to evaluate the remaining amount of developer. When the remaining amount of the developer is small, most of the light incident on the light guide member leaks into the space in the tubular member through the light leaking portion, and only a part of the light is guided to the light receiving means. On the other hand, when the remaining amount of the developer is large, the flexible tubular member comes into contact with the light guide member by the pressure of the developer. Therefore, the tubular member blocks the light leaking portion, and most of the light is guided to the light receiving means while reflecting inside the light guide member without leaking from the light leaking portion. By detecting this difference, the remaining amount of the developer can be evaluated. That is, unlike the conventional developer remaining amount detection device, the remaining amount of developer can be evaluated by a light guide member communicating from the light emitting means to the light receiving means. Further, since the light guide member is covered with the tubular member, the adhesion of the developer is suppressed. Therefore, the developer remaining amount detection device of the present invention can evaluate the remaining amount of developer without providing a cleaning member.

In addition, the light leakage portion of the developer remaining amount detection device of the present invention is emitted from the light emitting means and propagates through the light guide member.
sin ⁻¹ (n2 / n1) <θ <90
It is better if the region has a surface with an angle θ satisfying the following condition. In the conditions, n1 represents the refractive index of the light guide member, and n2 represents the refractive index of air. That is, since the angle θ in the above condition is larger than sin ⁻¹ (n2 / n1), the light reaching the light leakage portion is refracted without being totally reflected at that portion. Therefore, in a state where the remaining amount of the developer is small, light leaks to the outside through the light leakage portion. On the other hand, in a state where the remaining amount of the developer is large, leakage of light from the light leakage portion by the developer is suppressed, and most of the light is guided to the light receiving portion. Also, since the angle θ is smaller than 90 degrees, the light incident on the light guide member can be guided to the light receiving means without returning to the light emitting means. Therefore, the remaining amount of the developer can be evaluated by providing a surface satisfying the above conditions.

  Further, the light guide member of the developer remaining amount detecting device of the present invention is a linear member that transmits light, and a part of the surface thereof is coated for preventing light transmission, and a light leakage portion. Is better if it is an uncovered portion of the light guide member. As such a light guide member, for example, a material that propagates light by repeating reflection, such as an optical fiber, corresponds. Even in such a member, when the remaining amount of the developer is small, a part of the light leaks to the outside through the non-covering portion (light leakage portion). On the other hand, in a state where the remaining amount of the developer is large, most of the light is transmitted to the light receiving means while being repeatedly reflected. Thereby, the remaining amount of the developer can be evaluated. Further, the developer remaining amount detection device itself is simple.

  Another developer remaining amount detecting device of the present invention is a developer remaining amount detecting device for detecting the remaining amount of developer in the developer reservoir, and includes a light emitting means, a light receiving means, and a light emitting means side. Is a member that guides the light incident from one end to the other end, and the other end is a light emitting side light guide member located in the developer reservoir, and receives light incident from one end. A member that leads to the end on the means side, one end of which is located in the developer reservoir, and has flexibility, is located in the developer reservoir and emits light A tubular member into which the light guide member and the light receiving member are inserted, and at least one of the other end of the light emitting member and the one end of the light receiving member is a developer. It is provided so as to be movable depending on the remaining amount.

  That is, the developer remaining amount detecting device includes two light guide members, a light-emitting side light guide member and a light-receiving side light guide member. Then, the remaining amount of the developer is evaluated by transmitting and receiving light between the light emitting side light guide member and the light receiving side light guide member. For example, the light-emitting side light guide member and the light-receiving side light guide member are provided so as not to face each other when the developer remaining amount is small and to face each other when the developer remaining amount is large. Accordingly, when the remaining amount of developer is small, the light guided to the light receiving unit is small, and when the remaining amount of developer is large, the light guided to the light receiving unit is large. Therefore, the remaining amount of developer can be evaluated. Further, these light guide members are inserted into a flexible tubular member. Therefore, the developer does not adhere to these light guide members. Therefore, it is not necessary to provide a member for cleaning those parts.

  The image forming apparatus of the present invention is an image forming apparatus that forms an image with a developer and detects the remaining amount of the developer, and is incident on one end of the developer reservoir for storing the developer. A member for guiding light to the other end, at least a part of the light guide path being located in the developer reservoir, and a light emitting means installed at one end of the light guide; A light receiving means installed at the other end of the light guide member, and a tubular member having flexibility and positioned in the developer reservoir and having the light guide member inserted therein, The surface is provided with a light leaking portion for leaking light emitted from the light emitting means and propagating through the light guide member to the outside of the light guide member at a position in the developer reservoir. .

  Another image forming apparatus of the present invention is an image forming apparatus that forms an image with a developer and detects the remaining amount of the developer, a developer reservoir for storing the developer, a light emitting means, , A light receiving means, a member for guiding light incident from the end on the light emitting means side to the other end, and a light emitting side light guide member whose other end is located in the developer reservoir, A member that guides light incident from the end to the end on the light receiving means side, one end of which is located in the developer reservoir, and has flexibility and a developer A tubular member located in the reservoir and having the light-emitting side light guide member and the light-receiving side light guide member inserted therein, the other end of the light-emitting side light guide member and one end of the light-receiving side light guide member Are provided so as to be movable depending on the remaining amount of the developer.

  In the present invention, since the light guide member is covered with the tubular member, the developer does not adhere. Therefore, there is no need to provide a member for cleaning. Therefore, according to the present invention, a compact and highly accurate developer remaining amount detection device and an image forming apparatus including the same are realized without providing a member for cleaning the light guide member.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below in detail with reference to the accompanying drawings. In the present embodiment, the present invention is applied to an electrophotographic printer.

[First embodiment]
As shown in FIG. 1, the printer 100 according to the first embodiment includes a photosensitive drum 51, a charger 52, a print head 53, a developing device 60, a transfer roller 54, a cleaner 55, a fixing unit 70, and the like. have. The charger 52 charges the surface of the photosensitive drum 51 uniformly. The print head 53 forms an electrostatic latent image on the surface of the uniformly charged photosensitive drum 51 by performing exposure according to image data. The developing device 60 develops the electrostatic latent image formed on the surface of the photosensitive drum 51 with toner to form a toner image. The transfer roller 54 transfers the toner image formed on the surface of the photosensitive drum 51 onto the recording medium 80. The cleaner 55 collects toner remaining on the surface of the photosensitive drum 51 after transfer. The fixing unit 70 is for fixing the transferred toner image on the recording medium 80.

  Next, the developing device 60 will be described in detail. As shown in FIG. 1, the developing device 60 includes a toner container 6 that stores toner, a developing roller 61 that carries toner, and a stirring roller 62 that stirs the toner in the toner container 6. Yes. The developing roller 61 is disposed so as to face the photosensitive drum 51. Development is performed at a position where the developing roller 61 and the photosensitive drum 51 face each other. Further, the developing device 60 is provided with a toner remaining amount detecting unit 10 that detects the remaining amount of toner. A signal for evaluating the remaining amount of toner is output from the toner remaining amount detecting unit 10, and the control unit 7 evaluates the remaining amount of toner.

2 and 3 are diagrams illustrating a schematic configuration of the toner remaining amount detecting unit 10 according to the present embodiment. FIG. 2 shows a state when the remaining amount of toner 5 in the toner container 6 is small, and FIG. 3 shows a state when the remaining amount of toner 5 is large. The toner remaining amount detection unit 10 is provided with a rod-shaped light guide member 3 that passes through the toner container 6. As the light guide member 3, a material having excellent transparency such as polycarbonate is applicable. A light emitting element 1 (light emitting diode or the like) is provided at one end of the light guide member 3, and a light receiving element 2 (photodiode or the like) is provided at the other end. In addition, the light guide member 3 is provided with a light leakage portion 4 that is located in the toner container 6 and leaks light incident on the light guide member 3 to the outside. Specifically, as shown in FIGS. 2 and 3, the light leaking portion 4 is a portion having a surface having an angle θ that satisfies the following condition (1) with respect to the incident direction of the light ray incident on the light leaking portion 4. It is.
sin ⁻¹ (n2 / n1) <θ <90 (1)
In condition (1), n1 means the refractive index of the light guide member 3, and n2 means the refractive index of air.

When the angle θ in the condition (1) is smaller than sin ⁻¹ (n2 / n1), most of the light guided to the light leaking portion 4 even when the toner container 6 is empty. Is reflected in the light guide member 3. That is, total reflection occurs. For this reason, there is no light leaking from the light leaking portion 4, and it cannot be distinguished from the case where the remaining amount of the toner 5 is large. When the angle θ is larger than 90 degrees, the incident light is reflected toward the light emitting element 1, and the light does not reach the light receiving element 2. Therefore, it is appropriate that the light leakage part 4 satisfies the condition (1).

  A flexible tube 8 is provided in the toner container 6. The light guide member 3 is inserted into the tube 8. That is, the portion of the light guide member 3 in the toner container 6 is covered with the tube 8, so that the toner 5 does not adhere. Of course, the toner 5 does not adhere to the light leakage portion 4. The tube 8 has a good color such as silver or white with excellent reflection efficiency. Moreover, the member which covers the light guide member 3 is not limited to a tube, and for example, a film formed in a tubular shape may be used. When the remaining amount of toner 5 is large (see FIG. 3), the tube 8 is pressed by the toner 5 and is in close contact with the light guide member 3. At that time, the tube 8 is also in close contact with the light leakage portion 4 of the light guide member 3. On the other hand, when the remaining amount of the toner 5 is low (see FIG. 2), a space is generated in the tube 8 without being pressed by the toner 5. Therefore, the light in the light guide member 3 leaks out of the light guide member 3. Note that the tube 8 covers all portions of the light guide member 3 inside the toner container 6, but may cover only the light leakage portion 4.

  Next, the operation of the toner remaining amount detection unit 10 of this embodiment will be described. The toner remaining amount detection unit 10 of the present embodiment receives light emitted from the light emitting element 1 by the light receiving element 2 and analyzes the detection signal of the light receiving element 2 to thereby analyze the remaining amount of toner in the toner container 6. Is to evaluate. First, the operation in a state where the remaining amount of toner 5 is low (see FIG. 2) will be described. First, light emitted from the light emitting element 1 enters one end of the light guide member 3. The incident light propagates through the light guide member 3 and reaches the light leakage part 4. Most of the light reaching the light leaking portion 4 is refracted and leaks into the space in the tube 8, and a part of the light is reflected inside the light guide member 3 and guided to the other end of the light guide member 3. Light emitted from the other end of the light guide member 3 is guided to the light receiving element 2. That is, when the remaining amount of the toner 5 is low, light leaks at the light leaking portion 4, so that only a part of the light emitted by the light emitting element 1 is received by the light receiving element 2.

  Next, the operation when the remaining amount of toner 5 is large (see FIG. 3) will be described. This is the same as when the remaining amount of toner 5 is low until the light emitted from the light emitting element 1 reaches the light leaking portion 4. When the remaining amount of toner 5 is large, the tube 8 is pressed by the toner 5. Therefore, the surface of the light guide member 3 including the light leakage part 4 is in close contact with the tube 8. As a result, most of the light guided to the light leakage portion 4 is reflected by the tube 8 and light leakage is suppressed. Then, most of the light reaching the light leaking portion 4 is reflected inside the light guide member 3 and guided to the other end of the light guide member 3. Light emitted from the other end of the light guide member 3 is guided to the light receiving element 2. That is, when the remaining amount of the toner 5 is large, most of the light emitted by the light emitting element 1 is received by the light receiving element 2. Therefore, the remaining amount of toner in the toner container 6 can be evaluated according to the detection signal of the light receiving element 2 and the fluctuation state.

[Second form]
The image forming apparatus according to the second embodiment is a modification of the toner remaining amount detecting unit 10 shown in the first embodiment. As shown in FIG. 4 or 5, the toner remaining amount detection unit 20 of the present embodiment is provided with the light emitting element 1 and the light receiving element 2 on the same side surface side of the toner container 6. 4 shows the case where the remaining amount of the toner 5 in the toner container 6 is small, and FIG. 5 shows the case where the remaining amount of the toner 5 is large. In the toner remaining amount detection unit 20 of the present embodiment, the light guide member 3 is inserted into the toner container 6 and extracted from above the same side surface. That is, the light guide member 3 has a substantially U-shape. Also in this embodiment, the light guide element 3 is provided with the light emitting element 1 at one end and the light receiving element 2 at the other end. In addition, the light guide member 3 is provided with light leakage portions 4A and 4B that satisfy the above-described condition (1). Similarly to the first embodiment, a tube 8 is provided in the toner container 6, and the light guide member 3 is inserted into the tube 8. Therefore, the toner 5 does not adhere to the surface of the light guide member 3 including the light leakage portions 4A and 4B.

  Similarly to the first embodiment, the toner remaining amount detection unit 20 of the present embodiment also receives light emitted by the light emitting element 1 by the light receiving element 2 and analyzes the detection signal of the light receiving element 2 to analyze the toner. The remaining amount of toner in the container 6 is evaluated. When the remaining amount of the toner 5 is low, most of the light that has reached the light leakage portions 4A and 4B leaks to the outside, and a part of the light is reflected inside the light guide member 3 to the other end of the light guide member 3. Led. On the other hand, when the remaining amount of the toner 5 is large, light leakage is suppressed by the tube 8, so that most of the light incident on the light leakage portions 4 </ b> A and 4 </ b> B is reflected inside the light guide member 3 to guide the light. Guided to the other end of the member 3. Due to this difference, the remaining amount of toner in the toner container 6 can be evaluated. The light receiving element 2 is spaced from the light emitting element 1 so as not to be affected by light from the light emitting element 1 and not through the light guide member 3.

[Third embodiment]
The image forming apparatus according to the third embodiment is a modification of the toner remaining amount detecting unit 10 shown in the first embodiment. The toner remaining amount detection unit 30 of this embodiment uses an optical fiber as a light guide member. As shown in FIG. 6 or FIG. 7, the optical fiber has a core portion 3 that transmits light and a covering portion 9 that covers the core portion. In this embodiment, the core portion 3 of the optical fiber is applied as the light guide member. Furthermore, in this embodiment, the light guide member 3 is covered only on the outside of the toner container 6. That is, a portion of the light guide member 3 in the toner container 6 is not covered, and light leaks from the portion. Therefore, all the portions in the toner container 6 on the surface of the light guide member 3 are configured to correspond to the light leakage portion. 6 shows a case where the remaining amount of toner 5 in the toner container 6 is small, and FIG. 7 shows a case where the remaining amount of toner 5 is large. Similarly to the first embodiment, a tube 8 is provided in the toner container 6, and an optical fiber is inserted into the tube 8. For this reason, the toner 5 does not adhere to the core portion 3.

  Similarly to the first embodiment, the toner remaining amount detection unit 30 of the present embodiment receives light emitted from the light emitting element 1 by the light receiving element 2 and analyzes the detection signal of the light receiving element 2 to analyze the toner. The remaining amount of toner in the container 6 is evaluated. When the remaining amount of the toner 5 is low, most of the light incident on the core portion 3 leaks to the outside, and the remaining slight light is guided to the other end of the optical fiber. On the other hand, when the remaining amount of the toner 5 is large, the tube 8 pressed by the toner 5 substitutes for the covering portion 9, and most of the light incident on the core portion 3 is repeatedly reflected in the core portion 3. Guided to the other end of the fiber. Due to this difference, the remaining amount of toner in the toner container 6 can be evaluated.

[Fourth form]
The image forming apparatus according to the fourth embodiment is a modification of the toner remaining amount detecting unit 10 shown in the first embodiment. As shown in FIG. 8 or FIG. 9, the toner remaining amount detection unit 40 of the present embodiment includes a light guide member 3A on the light emitting side and a light guide member 3B on the light receiving side as light guide members. That is, similar to the conventional toner remaining amount detecting device, the light emitted from the end of the light guide member 3A on the light emitting side is received by the end of the light guide member 3B on the light receiving side. The toner remaining amount detecting unit 40 of this embodiment is different from the conventional toner remaining amount detecting device in that a tube 8 similar to that of the first embodiment is provided. Therefore, the toner 5 does not adhere to each light guide member, and a cleaning member for cleaning the end portion of each light guide member is unnecessary. 8 shows a case where the remaining amount of toner 5 in the toner container 6 is small, and FIG. 9 shows a case where the remaining amount of toner 5 is large.

  The light guide member 3A on the light emitting side is flexible, and is configured to be bent by its own weight or a spring as shown in FIG. 8 when the remaining amount of the toner 5 is small. In this embodiment, the light guide member 3A on the light emitting side is bent, but the light guide member 3B on the light receiving side may be bent. On the other hand, when the remaining amount of the toner 5 is large, the tube 8 is pressed by the toner 5 and the end of the light guide member 3A on the light emitting side is pushed up as shown in FIG. The end of the light guide member 3A on the light emitting side and the end of the light guide member 3B on the light receiving side face each other.

  Similarly to the first embodiment, the toner remaining amount detection unit 40 of the present embodiment receives light emitted from the light emitting element 1 by the light receiving element 2 and analyzes the detection signal of the light receiving element 2 to analyze the toner. The remaining amount of toner in the container 6 is evaluated. When the remaining amount of the toner 5 is small, the light guide member 3A on the light emitting side bends downward, so that the end portion of the light guide member 3A faces downward. Therefore, the light in the light guide member 3A is emitted downward from the end of the light guide member 3A, or leaks out toward the space in the tube 8 from a bent portion or the like. Therefore, only a small amount of light is guided to the light guide member 3B on the light receiving side. On the other hand, when the amount of remaining toner 5 is large, the light guide member 3 </ b> A on the light emitting side is pushed up together with the tube 8. Thereby, the end of the light guide member 3A on the light emitting side and the end of the light guide member 3B on the light receiving side face each other. Further, the tube 8 is in close contact with both light guide members. As a result, light leakage is suppressed. Therefore, most of the light incident on the light guide member 3A on the light emitting side is guided into the light guide member 3B on the light receiving side. Due to this difference, the remaining amount of toner in the toner container 6 can be evaluated.

  In this embodiment, the end of the light guide member 3A on the light emitting side faces the end of the light guide member 3B on the light receiving side when the remaining amount of the toner 5 is large. You may oppose when there is little state. That is, when the remaining amount of toner 5 is small, the end portions of the respective light guide members are opposed to each other, and when the remaining amount of toner 5 is large, the tube 8 is pushed down by the toner 5 and each light guide member is also pushed down. Thereby, when the remaining amount of the toner 5 is large, the end portions of the light guide members do not face each other. Therefore, since the amount of received light differs between when the amount of toner 5 is large and when the amount of toner 5 is small, the amount of toner remaining in the toner container 6 can be evaluated.

  In addition, the light guide member 3A on the light emitting side of the present embodiment is a flexible member as a whole. However, the present invention is not limited to this. For example, a member having only a part of the flexibility may be used. That is, it is only necessary that the end of the light guide member 3A on the light emitting side can be moved by the remaining amount of toner 5.

  As described above in detail, the printer 100 according to the first embodiment includes the toner remaining amount detection unit 10 that detects the remaining amount of toner in the toner container 6. The toner remaining amount detection unit 10 includes a light guide member 3 that penetrates the toner container 6. The light-emitting element 1 is provided at one end of the light guide member 3 and the light-receiving element 2 is provided at the other end. That is, a light guide member 3 communicating from the light emitting element 1 to the light receiving element 2 is provided. Furthermore, the light leakage part 4 is provided on the surface of the light guide member 3, and the light guide member 3 is inserted into the tube 8 having flexibility. Thereby, when the remaining amount of the toner 5 is low, most of the light leaks from the light leaking portion 4 into the space in the tube 8, and only a part of the light is guided to the light receiving element 2. On the other hand, when the remaining amount of the toner 5 is large, most of the light is reflected and leaked to the light receiving element 2 because the tube 8 is in close contact with the surface of the light guide member 3 including the light leakage portion 4. . By detecting this difference, the remaining amount of toner can be evaluated. Since the light guide member 3 of the first embodiment suppresses the adhesion of the toner 5 by the tube 8, it is not necessary to provide a cleaning member as in the conventional toner remaining amount detecting device. Moreover, since the light guide member 3 communicates, high assembly accuracy is not required. In addition, the detection performance does not deteriorate after shipment because of communication. Accordingly, a compact and highly accurate developer remaining amount detection device and an image forming apparatus including the same are realized without providing a member for cleaning the light guide member.

In addition, the light leaking portion 4 is a portion having a surface having an angle θ that satisfies the condition (1) described above. That is, since the angle θ in the condition (1) is larger than sin ⁻¹ (n2 / n1), the light leaks out while being refracted by the light leaking part 4 without being totally reflected when the remaining amount of the toner 5 is small. To do. On the other hand, when the remaining amount of toner 5 is large, the toner suppresses light leakage. Therefore, since the amount of light reaching the light receiving element 2 differs between when the remaining amount of toner 5 is low and when it is high, it is possible to distinguish between these states. Further, since the angle θ is smaller than 90 degrees, the light can be guided to the light receiving element 2 side.

  In the toner remaining amount detection unit 20 of the second embodiment, the light emitting element 1 and the light receiving element 2 are provided on the same side surface side of the toner container 6. Even in such a form, the remaining amount of toner can be detected as in the first form. That is, the light guide member 3 does not necessarily need to penetrate the toner container 6 linearly, and a plurality of light leakage portions 4 may be combined. Therefore, the toner remaining amount detection unit 20 has a high degree of design freedom.

  In the third embodiment, the remaining toner amount detection unit 30 uses an optical fiber as the light guide member 3. The optical fiber does not cover a part of the surface of the core portion 3. Even in this case, the remaining amount of toner can be evaluated. Therefore, it is not necessary to provide a surface satisfying the condition (1) on a part of the surface of the core portion 3. Therefore, a simple toner remaining amount detecting device is realized.

  In addition, the remaining toner amount detection unit 40 according to the fourth embodiment includes a light guide member 3A on the light emitting side and a light guide member 3B on the light receiving side. In other words, light is transmitted and received using two light guide members instead of the light guide members communicated as in the first embodiment. This is the same as the conventional toner remaining amount detecting device, but in the toner remaining amount detecting unit 40 of the present embodiment, the opposing ends of both light guide members are covered with the tube 8. Therefore, the toner 5 does not adhere to those parts. Therefore, it is not necessary to provide a member for cleaning those parts. Therefore, the toner remaining amount detecting unit 40 of this embodiment is more compact than the conventional toner remaining amount detecting device.

  Note that this embodiment is merely an example and does not limit the present invention. Therefore, the present invention can naturally be improved and modified in various ways without departing from the gist thereof. For example, in the embodiment of the present invention, the light emitting element 1 and the light receiving element 2 are arranged outside the toner container 6, but all of these may be arranged in the toner container 6. That is, the light emitting element 1, the light receiving element 2, and the entire light guide member 3 may be provided in the toner container 6. However, even in this case, the light-emitting element 1 is disposed at one end of the light guide member 3 and the light-receiving element 2 is disposed at the other end.

  Further, the developer is not limited to toner. For example, a two-component developer containing toner and carrier may be used. In the embodiment, the present invention is applied to a printer, but the present invention is not limited to this. That is, even a copying machine, a fax machine, or the like can be applied as long as it has a developing unit for storing a developer. A color printer may also be used. Further, a tandem system or a 4-cycle system may be used.

It is sectional drawing which shows schematic structure of the printer which concerns on a 1st form. 4 is a cross-sectional view (toner remaining amount: low) showing a schematic configuration of a toner remaining amount detecting unit according to the first embodiment; FIG. FIG. 3 is a cross-sectional view (toner remaining amount: many) illustrating a schematic configuration of a toner remaining amount detecting unit according to a first embodiment. FIG. 6 is a cross-sectional view (toner remaining amount: low) showing a schematic configuration of a toner remaining amount detecting unit according to a second embodiment. FIG. 6 is a cross-sectional view (toner remaining amount: many) illustrating a schematic configuration of a toner remaining amount detecting unit according to a second embodiment. FIG. 10 is a cross-sectional view (toner remaining amount: low) showing a schematic configuration of a toner remaining amount detecting unit according to a third embodiment. FIG. 10 is a cross-sectional view (toner remaining amount: many) illustrating a schematic configuration of a toner remaining amount detecting unit according to a third embodiment. FIG. 10 is a cross-sectional view (toner remaining amount: low) illustrating a schematic configuration of a toner remaining amount detecting unit according to a fourth embodiment. FIG. 10 is a cross-sectional view (toner remaining amount: many) illustrating a schematic configuration of a toner remaining amount detecting unit according to a fourth embodiment.

Explanation of symbols

1 Light emitting element (light emitting means)
2 Light receiving element (light receiving means)
3 Light guide member 4 Light leaking part 6 Toner container (developer reservoir)
8 Tube (tubular member)
10 Toner remaining amount detection unit (developer remaining amount detection device)
100 printer (image forming apparatus)

Claims (6)

In the developer remaining amount detecting device for detecting the remaining amount of developer in the developer reservoir,
A light guide member for guiding light incident on one end to the other end, wherein at least part of the light guide path is located in the developer reservoir;
A light emitting means installed at one end of the light guide member;
A light receiving means installed at the other end of the light guide member;
A tubular member having flexibility and being located in the developer reservoir and having the light guide member inserted therein;
On the surface of the light guide member, a light leak that leaks light emitted from the light emitting means and propagating through the light guide member to the outside of the light guide member at a position in the developer reservoir. A developer remaining amount detecting device, wherein a developer remaining amount detecting device is provided. In the developer remaining amount detecting device according to claim 1,
The light leakage portion is emitted from the light emitting means, and with respect to the light beam propagating through the light guide member,
sin ⁻¹ (n2 / n1) <θ <90
A developer remaining amount detecting device comprising a surface having an angle θ satisfying the following condition.
n1: Refractive index of light guide member n2: Refractive index of air In the developer remaining amount detecting device according to claim 1,
The light guide member is a linear member that transmits light, and a part of the surface is coated to prevent light transmission;
The developer remaining amount detecting device, wherein the light leakage portion is an uncovered portion of the light guide member. In the developer remaining amount detecting device for detecting the remaining amount of developer in the developer reservoir,
Light emitting means;
A light receiving means;
A member that guides light incident from an end on the light emitting means side to the other end, and a light emitting side light guide member in which the other end is located in the developer reservoir;
A member that guides light incident from one end to the end on the light receiving means side, the light receiving side light guide member having one end located in the developer reservoir;
A flexible tubular member that is located in the developer reservoir and into which the light emitting side light guide member and the light receiving side light guide member are inserted;
At least one of the other end portion of the light emitting side light guide member and one end portion of the light receiving side light guide member is provided so as to be movable depending on the remaining amount of the developer. Quantity detection device. In an image forming apparatus that forms an image with a developer and detects the remaining amount of the developer,
A developer reservoir for storing the developer;
A light guide member for guiding light incident on one end to the other end, wherein at least part of the light guide path is located in the developer reservoir;
A light emitting means installed at one end of the light guide member;
A light receiving means installed at the other end of the light guide member;
A tubular member having flexibility and being located in the developer reservoir and having the light guide member inserted therein;
On the surface of the light guide member, a light leak that leaks light emitted from the light emitting means and propagating through the light guide member to the outside of the light guide member at a position in the developer reservoir. An image forming apparatus provided with a section. In an image forming apparatus that forms an image with a developer and detects the remaining amount of the developer,
A developer reservoir for storing the developer;
Light emitting means;
A light receiving means;
A member that guides light incident from an end on the light emitting means side to the other end, and a light emitting side light guide member in which the other end is located in the developer reservoir;
A member that guides light incident from one end to the end on the light receiving means side, the light receiving side light guide member having one end located in the developer reservoir;
A flexible tubular member that is located in the developer reservoir and into which the light emitting side light guide member and the light receiving side light guide member are inserted;
At least one of the other end portion of the light emitting side light guide member and one end portion of the light receiving side light guide member is provided so as to be movable depending on the remaining amount of the developer. Quantity detection device.

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