JP2007034181A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To precisely detect a toner. <P>SOLUTION: Each of developing units 4Y, 4M, 4C, and 4B of a toner supply system includes a developing unit body 4a, a toner agitating member 4b, a developing roller 4c, a light emitting device 4d, a light receiving device 4e, a first detection light guide 4f, and a second detection light guide 4g. The developing roller 4c is freely rotatably attached to the developing unit body 4a. The light emitting device 4d is attached to a color printer body 11 on the side face side of the developing unit body 4a in a revolving shaft direction of the developing roller 4c. The light receiving device 4e is attached to the color printer body 11 on the outer peripheral surface side of the developing unit body 4a around the revolving shaft of the developing roller 4c. The first detection light guide 4f is attached to the developing unit body 4a and guides detection light emitted from the light emitting device, into the developing unit body 4a. The second detection light guide 4g is attached to the developing unit body 4a and guides detection light guided into the developing unit body 4a by the first detection light guide, toward the light receiving device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  A conventional cartridge type developing device mainly includes a developing device main body, a toner stirring member, a developing roller, a light emitting device, a light receiving device, a first detection light guide, a second detection light guide, and a sheet-like shape. (See Patent Document 1). A process cartridge is detachably attached to the developing device main body. The toner agitating member agitates the toner contained in the developing device main body. The developing roller adheres toner to the electrostatic latent image on the surface of the photosensitive drum. The light emitting element emits detection light for detecting the remaining amount of toner. The light receiving element receives detection light for detecting the remaining amount of toner. The first detection light guide guides the detection light emitted from the light emitting element to the inside of the developing device main body. The second detection light guide guides the detection light guided to the inside of the developing device main body by the first detection light guide to the light receiving element. The sheet-shaped scraper is mounted on the toner stirring member, and cleans the incident surface of the first detection light guide and the emission surface of the second detection light guide.

In such a developing device, the light emitting element is arranged at the lower part of the side surface of the developing device body, and the light receiving element is arranged at the upper part of the side surface of the developing device body. The detection light emitted from the light emitting element is guided to the inside of the developing device main body by the first detection light guide, and is emitted upward from below the developing device main body. Then, the detection light emitted to the inside of the developing device main body enters the second detection light guide and is guided to the light receiving element by the second detection light guide. The remaining amount of toner stored in the developing device main body is detected according to the time interval at which the light receiving element receives the detection light. The sheet-shaped scraper cleans the incident surface of the first detection light guide and the emission surface of the second detection light guide when the toner stirring member rotates.
JP2002-123079

  In the conventional cartridge type developing device, the remaining amount of toner is detected as described above, and when it is detected that the toner is insufficient, the cartridge is replaced with a new process cartridge in which toner is supplied. Therefore, in the cartridge type developing device, detection for toner supply (toner full detection) is not performed, but only detection for toner shortage (toner remaining amount detection) is performed.

  On the other hand, in the toner replenishment type developing device, it is necessary to detect not only the remaining toner amount but also the full toner. Therefore, it is considered that the toner full detection in the toner replenishment type developer is performed in the same manner as the toner remaining amount detection in the cartridge type developer. The toner full detection can be performed by arranging the light emitting element and the light receiving element on the upper side of the developing device main body. More specifically, when the light emitting element and the light receiving element are arranged at the upper part of the side surface of the developing device main body, the detection light emitted from the light emitting element on the side surface of the developing device main body is guided to the inside of the developing device main body by the first detection light guide. It is burned. Then, the detection light is emitted from the first detection light guide to the second detection light guide so as to cross the toner replenishment upper limit surface, and is guided to the light receiving element on the side surface of the developing device main body by the second detection light guide.

  When toner full detection is performed in this way, a drive train for driving a toner agitating member, a developing roller, and the like is arranged on the side surface of the developing device main body, so that detection after passing the toner replenishment upper limit surface is performed. The distance until the light reaches the light receiving element becomes long, and the light receiving accuracy of the detection light in the light receiving element may be reduced. That is, the accuracy of toner full detection may be reduced.

  An object of the present invention is to enable accurate toner detection.

  An image forming apparatus according to a first aspect includes an image forming apparatus main body and a toner replenishment type developing device. The toner replenishment type developing device is mounted on the main body of the image forming apparatus. The toner supply type developing device includes a developing device main body, a toner stirring member, a developing roller, a light emitting device, a light receiving device, a first detection light guide, and a second detection light guide. The developing device main body can accommodate toner therein. The toner agitating member is rotatably mounted on the developing device main body and agitates the toner accommodated in the developing device main body. The developing roller is rotatably attached to the developing device main body, and adheres toner to the electrostatic latent image on the surface of the image carrier. The light emitting device emits detection light for detecting toner from either the side surface of the developing device main body in the rotation axis direction of the developing roller or the outer peripheral surface of the developing device main body around the rotation axis of the developing roller. It is mounted on either the image forming apparatus main body or the developing device main body so that light can be emitted in the direction toward the head. The light receiving device is attached to one of the image forming apparatus main body and the developing device main body so that the detection light from the inside of the developing device main body can be received on the outer peripheral surface of the developing device main body around the rotation axis of the developing roller. The first detection light guide is attached to the developing device main body, and guides the detection light emitted from the light emitting device to the inside of the developing device main body. The second detection light guide is attached to the developing device main body, and guides the detection light guided into the developing device main body by the first detection light guide to the light receiving device.

  In this toner replenishment type developing device, the image forming apparatus main body and the developing device main body are disposed on either the side surface of the developing device main body in the direction of the rotating shaft of the developing roller or the outer peripheral surface of the developing device main body around the rotating shaft of the developing roller. Detection light is emitted from the light emitting device attached to either one to the first detection light guide. Then, the detection light emitted from the light emitting device is guided to the inside of the developing device main body by the first detection light guide, and the detection light emitted to the inside of the developing device main body is incident on the second detection light guide. Then, the detection light incident on the second detection light guide is applied to either the image forming apparatus main body or the developer main body on the outer peripheral surface side of the developer main body around the rotation axis of the developing roller by the second detection light guide. It is guided to the installed light receiving device. Then, the replenishment state of the toner replenished in the developing device main body is detected according to the time interval when the light receiving device receives the detection light.

  Here, since the light receiving device is mounted on one of the image forming apparatus main body and the developing device main body on the outer peripheral surface side of the developing device main body around the rotation axis of the developing roller, the first detection light guide to the developing device main body. The distance from when the detection light emitted inside passes through the toner detection surface, for example, the replenishment upper limit surface to the light receiving device, can be shortened. Thereby, the light receiving accuracy of the detection light in the light receiving device can be improved. That is, toner detection can be performed with high accuracy.

  In the image forming apparatus according to a second aspect, in the image forming apparatus according to the first aspect, the first detection light guide has an emission surface for emitting the detection light in the direction of the second detection light guide. The second detection light guide has an incident surface on which the detection light emitted from the emission surface of the first detection light guide is incident. Then, the first detection light guide and the second detection light are arranged such that the detection optical path connecting the emission surface of the first detection light guide and the incident surface of the second detection light guide is shifted over the rotation axis of the developing roller above the toner stirring member. The guide is attached to the developing device main body.

  In this case, the detection light path connecting the exit surface of the first detection light guide and the entrance surface of the second detection light guide is configured to be different from the rotation axis of the developing roller above the toner stirring member. The detection light emitted from the light exit surface of the guide into the inside of the developing device main body can be surely passed through the toner detection surface, for example, the replenishment upper limit surface. Thereby, toner detection can be performed with high accuracy.

  An image forming apparatus according to a third aspect is the image forming apparatus according to the second aspect, further comprising a cleaning member. The cleaning member is mounted inside the developing device main body between the exit surface of the first detection light guide and the incident surface of the second detection light guide, and cleans toner adhering to the exit surface and the entrance surface.

  In this case, the toner attached to the exit surface of the first detection light guide and the entrance surface of the second detection light guide can be cleaned by the cleaning member. Accordingly, the detection light can be reliably emitted from the emission surface of the first detection light guide, and the detection light emitted from the emission surface can be reliably incident on the incidence surface of the second detection light guide. That is, toner detection can be performed with high accuracy.

  According to a fourth aspect of the present invention, in the image forming apparatus according to the third aspect, the cleaning member protrudes from the base end portion rotatably attached to the developing device main body toward the detection optical path side. And a sheet member that is mounted on the protrusion and cleans the incident surface and the output surface.

  In this case, when the rotating member including the base end portion and the pair of projecting portions is rotated, the exit surface of the first detection light guide and the entrance surface of the second detection light guide are cleaned by the sheet member attached to the projecting portion. can do. Accordingly, the detection light can be reliably emitted from the emission surface of the first detection light guide, and the detection light emitted from the emission surface can be reliably incident on the incidence surface of the second detection light guide. That is, toner detection can be performed with high accuracy.

  An image forming apparatus according to a fifth aspect includes an image forming apparatus main body and a rotary developing device. A toner replenishing type rotary developing device includes a rotary rack that has a rotation shaft and is rotatably mounted on the image forming apparatus main body via the rotation shaft, and is disposed adjacent to the rotation shaft and held by the rotary rack. The plurality of developing units according to any one of Items 1 to 4. This rotary developing device supplies toner to the surface of the photosensitive drum on which the electrostatic latent image is formed from each developing device arranged adjacent to the rotation axis, and forms a toner image on the photosensitive drum.

  In this case, by providing the rotary developing device with the developing device according to any one of claims 1 to 4, toner detection can be performed with high accuracy as described above.

  According to the present invention, since the light receiving device is mounted on the outer peripheral surface of the developing device main body around the rotation axis of the developing roller, the detection light emitted from the first detection light guide into the developing device main body is replenished with toner. The distance from passing through the upper limit surface to reaching the light receiving device can be shortened. Thereby, the light receiving accuracy of the detection light in the light receiving device can be improved.

  In addition, since the detection optical path connecting the exit surface of the first detection light guide and the entrance surface of the second detection light guide is different from the rotation axis of the developing roller above the toner stirring member, the first detection light guide Therefore, the detection light emitted from the light emitting surface to the inside of the developing device main body can surely pass through the upper surface of the toner supply.

  Further, the toner attached to the emission surface of the first detection light guide and the incident surface of the second detection light guide can be cleaned by the cleaning member. Accordingly, the detection light can be reliably emitted from the emission surface of the first detection light guide, and the detection light emitted from the emission surface can be reliably incident on the incidence surface of the second detection light guide.

  From the above, the image forming apparatus according to the present invention can perform toner detection with high accuracy. Even when the image forming apparatus has a rotary developing device, toner detection can be performed with high accuracy.

  FIG. 1 is a diagram showing a schematic configuration of a color printer in which an embodiment of the present invention is adopted. As shown in FIG. 1, the color printer 100 mainly includes a color printer main body 11, an image forming unit 10, a toner container 8, and a toner supply pipe 13. The image forming unit 10 is provided substantially at the center of the color printer main body 11.

  The image forming unit 10 includes a photosensitive drum 1, a charging device 2, a rotary developing device 4, a transfer device 5, a cleaning device 6, and a laser unit 12. The charging device 2, the rotary developing device 4, the transfer device 5, the cleaning device 6, and the laser unit 12 are disposed around the photosensitive drum 1. A fixing device 7 is disposed downstream of the photosensitive drum 1 in the sheet conveyance direction. The fixing device 7 is a device for fixing the transferred toner image to a transfer material. A paper feed unit 20 is provided below the image forming unit 10, and a paper feed roller 9 is provided in the paper feed direction from the paper feed unit.

  The photosensitive drum 1 is rotatably mounted inside the color printer main body 11. An electrostatic latent image is formed on the surface of the photosensitive drum 1 by the laser unit 12. The charging device 2 is installed above the photosensitive drum 1 and is a device for uniformly charging the photosensitive drum 1.

  The transfer device 5 is a device for transferring the toner image on the photosensitive drum 1 to a sheet, and includes an intermediate transfer belt 51, primary transfer rollers 52 and 53, a driving roller 55, a secondary transfer counter roller 54, and a secondary transfer. A roller 56 is provided. The intermediate transfer belt 51 is wound around each of the primary transfer rollers 52 and 53, the driving roller 55, and the secondary transfer counter roller 54. The intermediate transfer belt 51 is rotated around the primary transfer rollers 52 and 53, the drive roller 55, and the secondary transfer counter roller 54 by the drive force of the drive roller 55. The toner image formed on the photosensitive drum 1 is transferred to the intermediate transfer belt 51, and the transferred toner image is temporarily held. The secondary transfer roller 56 is disposed on the outer peripheral surface of the intermediate transfer belt 51 at a position facing the secondary transfer counter roller 54. The secondary transfer roller 56 secondarily transfers the toner image onto the transfer material.

  The cleaning device 6 is a device for removing deposits such as residual developer remaining on the photosensitive drum 1. In the color printer 100, a cleaning blade is provided.

  The laser unit 12 is mounted inside the color printer main body 11. The laser unit 12 scans the photosensitive drum 1 based on image information processed by a controller (not shown) to form an electrostatic latent image on the photosensitive drum 1. The laser unit 12 includes a semiconductor laser, various lenses, a polygon mirror, a mirror rotation motor, and the like.

  The toner container 8 is a container for supplying toner to the rotary developing device 4. As shown in FIG. 1, the toner container 8 includes a plurality of containers such as a yellow container 8Y, a magenta container 8M, a cyan container 8C, and a black container 8B. The plurality of containers 8Y, 8M, 8C, and 8B are arranged side by side in the rotational axis direction of the photosensitive drum 1, that is, the rotational axis 41 direction of the rotary developing device 4 above the photosensitive drum 1 (upper side in FIG. 1). It is mounted inside the color printer main body 11.

  The plurality of toner supply pipes 13 have toner supply tubes 13a. The plurality of toner supply pipes 13 are attached to the toner container 8 through the toner supply tube 13 a and are disposed between the laser unit 12 and the photosensitive drum 1. Here, each of the four toner supply pipes 13 is attached to each of the plurality of containers 8Y, 8M, 8C, and 8B via the plurality of toner supply tubes 13a, and the rotary shaft 41 of the rotary developing device 4 is installed. They are arranged side by side.

  Each of the four toner supply pipes 13Y, 13M, 13C, 13B is inserted into the rotary developing device 4 at a predetermined rotational position of the rotary developing device 4, so that each color toner is supplied to the rotary developing device 4. For example, the toner replenishing pipe 13Y attached to the container 8Y replenishes yellow toner to a yellow developing device 4Y of the rotary developing device 4 described later. A toner supply pipe 13M attached to the container 8M supplies magenta toner to a magenta developing device 4M of the rotary developing device 4 described later. A toner replenishing pipe 13C attached to the container 8C replenishes cyan toner to a cyan developing device 4C of the rotary developing device 4 described later. A toner replenishing pipe 13B attached to the container 8B replenishes black toner to a black developing device 4B of the rotary developing device 4 described later.

  The rotary developing device 4 is a device that forms toner images on the photosensitive drum 1 by supplying toner to the surface of the photosensitive drum 1 on which the electrostatic latent image is formed. The rotary developing device 4 is rotatably mounted inside the color printer main body 11. The rotary developing device 4 includes a rotary rack 40 and a plurality of developing devices 4Y, 4M, 4C, 4B.

  The rotary rack 40 has a rotating shaft 41, and is rotatably mounted on the color printer main body 11 through the rotating shaft 41. The rotary rack 40 sequentially moves each of the plurality of developing devices 4Y, 4M, 4C, and 4B to a developing position facing the photosensitive drum 1 while rotating around a rotating shaft 41 by a rotating unit (not shown).

  The four developing devices 4Y, 4M, 4C, and 4B are arranged adjacent to each other around the rotation shaft 41 and are held by the rotary rack 40. Here, the yellow developing unit 4Y, the magenta developing unit 4M, the cyan developing unit 4C, and the black developing unit 4B are arranged in the order of 4Y, 4M, 4C, 4B in the circumferential direction of the rotary rack 40, that is, the circumferential direction around the rotation shaft 41. Are arranged side by side and held by the rotary rack 40. These four developing units 4Y, 4M, 4C, 4B are arranged at intervals of about 90 degrees in the circumferential direction.

  As shown in FIGS. 2 and 3, each of the four developing devices 4Y, 4M, 4C, and 4B includes a developing device body 4a, a toner stirring member 4b, a developing roller 4c, a light emitting device 4d, and a light receiving device 4e. The first detection light guide 4f, the second detection light guide 4g, the cleaning member 4h, and the toner supply roller 4i are provided. The toner supply roller 4i is rotatably mounted inside the developing device main body 4a between the toner stirring member 4b and the developing roller 4c. In FIG. 3, the sheet member 445h is not shown so that members other than the cleaning member 4h can be easily described.

  The toner agitating member 4b is for agitating the toner accommodated in the developing device main body 4a, and is rotatably mounted in the developing device main body 4a. Here, the toner stirring member 4b is rotatably mounted inside the developing device body 4a on the side away from the photosensitive drum 1 and the developing roller 4c, that is, on the rotary shaft 41 side of the rotary rack 40.

  The developing roller 4c is for attaching the toner contained in the developing device main body 4a to the electrostatic latent image on the surface of the photosensitive drum 1. The developing roller 4c has a rotation shaft 44c, and is rotatably mounted inside the developing device main body 4a via the rotation shaft 44c. Here, the developing roller 4 c is rotatably mounted inside the developing device body 4 a on the outer peripheral surface side of the rotary rack 40.

  The light emitting device 4d is a device that emits detection light for detecting toner fullness, and is mounted on the color printer main body 11 on the outer surface side of the developing device main body 4a in the direction of the rotation shaft 44c of the developing roller 4c. . Specifically, the light emitting device 4d is mounted on the color printer main body 11 at a position spaced apart from one outer surface of the developing device main body 4a in the direction of the rotation axis 44c of the developing roller 4c. The light emitting device 4d has a light emitting element 44d. The light emitting device 4d is mounted on the color printer main body 11 on the one outer surface side of the developing device main body 4a so that the front end portion of the light emitting element 44d, that is, the light emitting portion faces the direction of a first detection light guide 4f described later. The light emitting element 44d emits the detection light toward the first detection light guide 4f so that the detection light is parallel to the rotation axis of the developing roller 4c.

  The light receiving device 4e is a device that receives detection light for detecting toner fullness, and is mounted on the color printer main body 11 on the outer peripheral surface side of the developing device main body 4a around the rotation shaft 44c of the developing roller 4c. Specifically, the light receiving device 4e is mounted on the color printer main body 11 at a position spaced from the outer peripheral surface of the developing device main body 4a around the rotation shaft 44c of the developing roller 4c. The light receiving device 4e has a light receiving element 44e. The light receiving device 4e is mounted on the color printer main body 11 on the outer peripheral surface side of the developing device main body 4a so that the front end portion of the light receiving element 44e, that is, the light receiving portion faces the direction of a second detection light guide 4g described later.

  In such a light emitting device 4d and light receiving device 4e, when the four developing device main bodies 4a rotate together with the rotary rack 40 and stop at a predetermined position, that is, one developing device main body 4a of the four developing device main bodies 4a. Is stopped at the position shown in FIG. 2, detection light is emitted from the light emitting device 4d, and the detection light emitted from the light emitting device 4d is received through first and second detection light guides 4f and 4g described later. The light is received by the device 4e.

  The first detection light guide 4f is for guiding the detection light emitted from the light emitting device 4d to the inside of the developing device main body 4a, and is attached to the developing device main body 4a. For example, the first detection light guide 4f is mounted on one side surface of the developing device body 4a, that is, on the side surface of the developing device body 4a on one end side of the rotation shaft 44c of the developing roller 4c. In the first detection light guide 4f, a first incident portion (not shown) of detection light is disposed on the outer surface of the developing device body 4a so as to face the light emitting element 44d of the light emitting device 4d, and the first emission of detection light is performed. The part 14f is disposed inside the developing device main body 4a. The first detection light guide 4f has an emission surface 44f that is formed in the first emission part 14f and emits detection light in the direction of the second detection light guide 4g. Here, first, the detection light is guided into the inside of the developing device main body 4a by the first detection light guide 4f so as to be parallel to the rotation axis of the developing roller 4c. Then, the detection light is emitted from the emission surface 44f of the first detection light guide 4f in the direction of the incident surface 44g of the second detection light guide 4g described later, that is, in the direction away from the toner stirring member 4b.

  The second detection light guide 4g is for guiding the detection light guided to the inside of the developing device main body 4a by the first detection light guide 4f to the light receiving device 4e, and is attached to the developing device main body 4a. For example, the second detection light guide 4g is attached to the developing device body 4a on the upper surface side inside the developing device body 4a, that is, on the outer peripheral surface side of the rotary rack 40. In the second detection light guide 4g, the second incident portion 14g of the detection light is disposed inside the developing device body 4a, and the second emission portion (not shown) of the detection light faces the light receiving element 44e of the light receiving device 4e. In this way, it is arranged on the outer peripheral surface of the developing device main body 4a. The second detection light guide 4g has an incident surface 44g that is formed in the second incident portion 14g and receives the detection light emitted from the emission surface 44f of the first detection light guide 4f. Here, the detection light incident from the incident surface 44g is guided by the second detection light guide 4g in the direction of the light receiving device 4e attached to the developing device main body 4a, that is, in the direction away from the developing roller 4c.

  By attaching the first detection light guide 4f and the second detection guide to the developing device main body 4a as described above, the detection is made to connect the emission surface 44f of the first detection light guide 4f and the incident surface 44g of the second detection light guide 4g. The detection light is guided from the emission surface 44f of the first detection light guide 4f to the second detection light guide so that the optical path R crosses the rotation shaft 44c of the developing roller 4c, that is, the rotation shaft 44b of the toner stirring member 4b, above the toner stirring member 4b. The light can be emitted to the 4 g incident surface 44 g.

  The first and second detection light guides 4f and 4g are made of synthetic resin that can transmit light and totally reflect light. The refractive index of the synthetic resin is desirably set in the range of 1.2 to 1.7. Examples of such a synthetic resin include an acrylic resin and a polystyrene resin.

  As shown in FIGS. 2 and 4, the cleaning member 4h is for cleaning toner adhering to the exit surface 44f of the first detection light guide 4f and the entrance surface 44g of the second detection light guide 4g. The cleaning member 4h is mounted inside the developing device main body 4a between the emission surface 44f of the first detection light guide 4f and the incident surface 44g of the second detection light guide 4g. The cleaning member 4h includes a rotating member 441h and a sheet member 445h. The rotating member 441h includes a base end portion 442h that is rotatably attached to the developing device main body 4a, and a pair of protruding portions 443h that are formed to protrude from the base end portion 442h toward the detection optical path R side. In such a rotating member 441h, the free ends of the pair of protrusions 443h are opened, and it is considered that toner accumulation is not hindered by the pair of protrusions 443h. Therefore, the toner accumulation state in the vertical direction can be accurately detected by the detection light between the first detection light guide 4f and the second detection light guide 4g. The sheet member 445h is for cleaning the entrance surface 44g and the exit surface 44f, and is attached to each of the pair of protrusions 443h. In the cleaning member 4h, when the rotating member 441h is rotated by driving means (not shown), the outer surface of the sheet member 445h attached to the protruding portion 443h of the rotating member 441h comes into contact with the emission surface 44f and the incident surface 44g. Thus, the toner adhering to the exit surface 44f and the entrance surface 44g is cleaned.

  In the rotary developing device having the developing devices 4Y, 4M, 4C, and 4B as described above, the light receiving device 4e is mounted on the color printer main body 11 on the outer peripheral surface side of the developing device main body 4a around the rotation shaft 44c of the developing roller 4c. Therefore, the detection light emitted from the first detection light guide 4f to the inside of the developing device main body 4a passes through the upper limit surface of the toner supply and then reaches the light receiving device 4e via the second detection light guide 4g. The distance can be shortened. Thereby, the light receiving accuracy of the detection light in the light receiving device 4e can be improved. Further, the detection optical path R connecting the emission surface 44f of the first detection light guide 4f and the incident surface 44g of the second detection light guide 4g is different from the rotation shaft 44c of the developing roller 4c above the toner stirring member 4b. Therefore, the detection light emitted from the emission surface 44f of the first detection light guide 4f to the inside of the developing device main body 4a can be reliably passed through the toner replenishment upper limit surface. Furthermore, the toner attached to the exit surface 44f of the first detection light guide 4f and the entrance surface 44g of the second detection light guide 4g can be cleaned by the cleaning member 4h. Accordingly, the detection light can be reliably emitted from the emission surface 44f of the first detection light guide 4f, and the detection light emitted from the emission surface 44f can be reliably incident on the incidence surface 44g of the second detection light guide 4g. it can. From the above, the developing device according to the present invention can accurately detect toner fullness.

[Other Embodiments]
(A) The present invention can also be applied to an image forming apparatus having a color printing function, such as a copying machine, a printer, or a facsimile.

  (B) In the above embodiment, the light emitting device 4d has been shown as being disposed on the side surface side of the developing device main body 4a in the direction of the rotation shaft 44c of the developing roller 4c. Without being limited thereto, the light emitting device 4d may be disposed on the outer peripheral surface side of the developing device body 4a around the rotation shaft 44c of the developing roller 4c. When the light emitting device 4d is disposed on the outer peripheral surface side of the developing device main body 4a around the rotation shaft 44c of the developing roller 4c, the first detection light guide 4f is on the upper surface side of the developing device main body 4a, that is, on the outer peripheral surface side of the rotary rack 40. Placed in. Even in this case, the same effects as those described above can be obtained.

  (C) Although the first and second detection light guides 4f and 4g are mounted on the color printer main body 11 in the above embodiment, the mounting target of the first and second detection light guides 4f and 4g is shown. Is not limited to the above embodiment, and may be the developing device main body 4a. Even in this case, the same effects as those described above can be obtained.

1 is a schematic sectional view of a color printer according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of a developing device of the rotary developing device of the color printer. The internal perspective view of the one end side of the said developing device. FIG. 3 is a perspective view of a cleaning member of the developing device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Color printer 1 Photoconductor drum 4 Rotary developing device 4Y, 4M, 4C, 4B Developing device 40 Rotary rack 41 Rotary shaft of rotary rack 4a Developing device main body 4b Toner stirring member 4c Developing roller 44c Developing shaft of rotating roller 4d Light emitting device 4e Light receiving device 4f First detection light guide 44f Emission surface 4g Second detection light guide 44g Incidence surface 4h Cleaning member 441h Rotating member 442h Base end portion 443h Projection portion 445h Sheet member R Detection light path

Claims (5)

An image forming apparatus,
An image forming apparatus main body;
A developing device main body mounted on the image forming apparatus main body and capable of containing toner therein; a toner agitating member which is rotatably mounted on the developing device main body and stirs the toner stored inside the developing device main body; A developing roller that is rotatably mounted on the developing device main body and attaches the toner to the electrostatic latent image on the surface of the image carrier, and a detection light for detecting the toner in the direction of the rotation axis of the developing roller. The image forming apparatus main body and the development so that light can be emitted in a direction from one of a side surface of the developing device main body and an outer peripheral surface of the developing device main body around the rotation axis of the developing roller toward the inside of the developing device main body. A light emitting device mounted on one of the developing device main bodies, and receiving the detection light from the inside of the developing device main body on the outer peripheral surface of the developing device main body around the rotation axis of the developing roller. As described above, a light receiving device mounted on one of the image forming apparatus main body and the developing device main body, and detection light mounted on the developing device main body and emitted from the light emitting device is guided to the inside of the developing device main body. A toner replenishment type having a first detection light guide and a second detection light guide that is attached to the developing device main body and guides the detection light guided to the inside of the developing device main body by the first detection light guide to the light receiving device. A developing device,
An image forming apparatus comprising: The first detection light guide has an emission surface that emits the detection light in the direction of the second detection light guide,
The second detection light guide has an incident surface on which detection light emitted from the emission surface of the first detection light guide is incident,
The first detection light guide is arranged such that a detection optical path connecting the emission surface of the first detection light guide and the incident surface of the second detection light guide conflicts with the rotation shaft of the developing roller above the toner stirring member. And the second detection light guide are mounted on the developing device main body.
The image forming apparatus according to claim 1. The toner is attached to the inside of the developing device main body between the emission surface of the first detection light guide and the incident surface of the second detection light guide, and cleans the toner adhering to the emission surface and the incident surface. Cleaning member
The image forming apparatus according to claim 2, further comprising: The cleaning member includes a rotating member including a base end portion rotatably attached to the developing device main body, a protruding portion formed to protrude from the base end portion toward the detection optical path, and the protruding portion. A sheet member that is mounted and that cleans the entrance surface and the exit surface;
The image forming apparatus according to claim 3. An image forming apparatus,
An image forming apparatus main body;
The rotary rack having a rotation shaft and rotatably mounted on the image forming apparatus main body via the rotation shaft, and disposed adjacent to the periphery of the rotation shaft and held by the rotary rack. A toner replenishment type rotary developing device having a plurality of developing units according to any one of the above,
An image forming apparatus comprising:

Images