JP2019159160A - Developing device - Google Patents

Abstract

To provide a configuration capable of stably measuring a predetermined gap between a developing sleeve 302 and a regulation blade 303.SOLUTION: A developing container 301 stores a developer and includes a top plate member 20 which is a transmission part transmitting light. The developing sleeve 302 carries and conveys the developer in the developing container 301. The regulation blade 303 is arranged with a predetermined gap with respect to the developing sleeve 302 and regulates the layer thickness of the developer carried by the developing sleeve 302. A conveyance screw 305 supplies the developer to the developing sleeve 302, while conveying the developer in the developing container 301. The conveyance screw 305 has a whiteness degree of 70 or more.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a developing device for developing an electrostatic latent image formed on an image carrier with toner.

  In an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a multi-function machine having a plurality of these functions, an electrostatic latent image is formed on the surface of a photosensitive drum as an image carrier, and this is used as a developer by a developing device. And develop. Such a developing device carries and conveys a developer by a developing sleeve as a developer carrying member, and is placed on the developing sleeve by a regulating blade as a layer thickness regulating member disposed through a predetermined gap from the developing sleeve. Regulates developer layer thickness. Then, the developer whose layer thickness is regulated is transported to a development area facing the photosensitive drum, and the electrostatic latent image is developed as described above.

  The predetermined gap is required to be adjusted with high accuracy. As a configuration for adjusting the predetermined gap, a configuration has been proposed in which a part of the developing container is a transmissive portion that transmits light (Patent Document 1). In Patent Document 1, the light transmitted through the transmission part is reflected by a transport screw that transports the developer in the developing container, and the reflected light passes through a predetermined gap. Then, a camera is disposed at an external position facing the predetermined gap, and the predetermined gap through which the reflected light passes is photographed by the camera, so that the predetermined gap is measured and adjusted.

Japanese Patent Laid-Open No. 2006-95360

  However, in the case of the configuration described in Patent Document 1, the light reflectance of the conveying screw is not taken into consideration. In general, the conveying screw often has a low light reflectance such as black. When the reflectance of light is low, when a predetermined gap is photographed with a camera and the predetermined gap is measured, a measurement error becomes large and it is difficult to perform stable measurement.

  An object of this invention is to provide the structure which can measure stably the predetermined clearance gap between a developing agent carrier and a layer thickness control member.

  The present invention includes a developer container that contains a developer and has at least a transmission part that transmits light, a developer carrier that carries and conveys the developer in the developer container, and the developer carrier And a layer thickness regulating member that regulates the layer thickness of the developer carried on the developer carrier, and transports the developer in the developer container while developing the developer. And a conveying member to be supplied to the agent carrier, wherein the conveying member has a whiteness of 70 or more.

  The present invention also provides a developer container that contains a developer and has at least part of a light transmitting portion, a developer carrier that carries and conveys the developer in the developer container, and the developer A layer thickness regulating member that is disposed through a predetermined gap with the carrier and regulates the layer thickness of the developer carried on the developer carrier, and light that has entered the developer container from the transmission part is reflected. And a reflecting portion disposed so as to pass through the predetermined gap, wherein the reflecting portion has a whiteness of 70 or more.

  According to the present invention, it is possible to stably measure the predetermined gap between the developer carrying member and the layer thickness regulating member.

1 is a schematic configuration diagram of an image forming apparatus according to a first embodiment. FIG. 3 is a perspective view of a process cartridge according to the first embodiment. FIG. 3 is a cross-sectional view of the process cartridge according to the first embodiment. The developing device which concerns on 1st Embodiment (a) The perspective view seen from the front side, (b) The perspective view seen from the back side. The (a) perspective view of the adjustment mechanism of the control blade which concerns on 1st Embodiment, (b) Sectional drawing. The schematic diagram which shows the structure which measures the predetermined clearance gap concerning 1st Embodiment. The graph which shows the relationship between L value and a gap measurement value. 4A is a plan view and FIG. 2B is a cross-sectional view of a developing device according to a second embodiment.

<First Embodiment>
A first embodiment will be described with reference to FIGS. First, a schematic configuration of the image forming apparatus of the present embodiment will be described with reference to FIG.

[Image forming apparatus]
The full-color image forming apparatuses are mainly classified into a tandem type in which a plurality of image forming units are arranged side by side and a rotary type in which a plurality of developing devices are arranged in a cylindrical shape. As a transfer method, there are a direct transfer method in which a toner image is directly transferred from a photosensitive member to a recording material, and an intermediate transfer method in which a toner image is transferred to a recording material after being transferred to an intermediate transfer member.

  The image forming apparatus 100 according to the present embodiment is an intermediate transfer type tandem type full-color printer including four image forming units (process cartridges) PY, PM, PC, and PK each having a photosensitive drum 508 as an image carrier. is there. The image forming apparatus 100 generates a toner image (image) according to an image signal from a document reading apparatus (not shown) connected to the apparatus main body or a host device such as a personal computer connected to the apparatus main body so as to be communicable. Formed on recording material. Examples of the recording material include sheet materials such as paper, plastic film, and cloth. The image forming units PY, PM, PC, and PK form yellow (Y), magenta (M), cyan (C), and black (K) toner images, respectively.

  The operation of the image forming apparatus 100 will be described with reference to FIG. The recording material S is stored in the cassette 50 and is fed by the feeding mechanism 53 in accordance with the image forming timing. Here, the feeding mechanism 53 includes, for example, a feeding roller and a separation roller, and separates and feeds the recording materials stored in the cassette 50 by friction. Note that the recording material separation method may be a method using separation adsorption by air in addition to such a friction separation method.

  The recording material S delivered by the feeding mechanism 53 is transported to the registration roller 55 by the transport roller 54. The recording material S is fed to the secondary transfer portion T2 after skew correction and timing correction are performed by the registration roller 55. The secondary transfer portion T <b> 2 is a transfer nip portion formed by the outer peripheral surface of the portion of the intermediate transfer belt 506 stretched by the secondary transfer inner roller 503 and the secondary transfer outer roller 56. In the secondary transfer portion T2, by applying a predetermined pressure and an electrostatic load bias, the toner image carried on the intermediate transfer belt 506 is transferred onto the recording material S as described below.

  Next, a process for forming a toner image sent to the secondary transfer portion T2 at the same timing as the conveyance process of the recording material S to the secondary transfer portion T2 described above will be described. As described above, the image forming apparatus 100 includes the four image forming units PY, PM, PC, and PK. The four image forming units PY, PM, PC, and PK have substantially the same configuration except that the development colors are different. Therefore, the image forming unit PY will be described as a representative, and description of the other image forming units will be omitted.

  The configuration of the image forming unit PY will be described with reference to FIGS. 2 and 3 with reference to FIG. The image forming unit PY is a process cartridge including a drum cartridge 200 having a photosensitive drum 508 and a developing device (developing cartridge) 300, and is detachable from the main body of the image forming device 100. For example, the drum cartridge 200 and the developing device 300 can be separately attached to and detached from the apparatus main body by opening a door provided on the front side of the apparatus main body. Note that the front side of the image forming apparatus 100 is a side operated by the user, and an operation panel (operation unit) operated by the user is disposed, for example. On the other hand, the back side of the image forming apparatus 100 is the opposite side (back side) of the front side of the image forming apparatus 100.

  As shown in FIG. 3, a cylindrical photosensitive member, that is, a photosensitive drum 508 is disposed as an image carrier in the image forming unit PY. The photosensitive drum 508 is rotationally driven in the arrow direction in the figure. Around the photosensitive drum 508, a charging roller 201 as a charging unit, a developing device 300, a primary transfer roller 507 as a transfer unit, and a cleaning device 202 as a cleaning unit are arranged. Below the photosensitive drum 508 in FIG. 1, an exposure device (laser scanner in this embodiment) 511 as an exposure unit is arranged.

  The surface of the photosensitive drum 508 is uniformly charged by the charging roller 201 in advance. Then, the exposure device 511 emits light based on a signal of image information (image signal) sent to the apparatus main body, and is irradiated to the photosensitive drum 508 through the mirror 512 or the like as appropriate, and electrostatically is applied to the surface of the photosensitive drum 508. A latent image is formed.

  The electrostatic latent image formed on the photosensitive drum 508 in this way is developed by the developing device 300, and a toner image is formed on the photosensitive drum 508. Thereafter, a predetermined pressure and an electrostatic load bias are applied by the primary transfer roller 507, and the toner image is primarily transferred onto the intermediate transfer belt 506. The transfer residual toner remaining on the photosensitive drum 508 after the primary transfer is removed by the cleaning device 202. The detailed configuration of the developing device 300 will be described later.

  Next, the intermediate transfer belt 506 will be described. The intermediate transfer belt 506 is transported in the direction of arrow A in FIG. Therefore, parallel processing is performed by the image forming units PY, PM, PC, and PK. The image forming process for each color is performed at a timing for superimposing the upstream toner image primarily transferred onto the intermediate transfer belt 506. As a result, a full-color toner image is finally formed on the intermediate transfer belt 506 and conveyed to the secondary transfer portion T2.

  As described above, the full color toner image is secondarily transferred onto the recording material S in the secondary transfer portion T2 by the conveyance process and the image forming process of the recording material S described above. Thereafter, the recording material S is conveyed to the fixing device 58. The fixing device 58 melts and fixes the toner image on the recording material S by a predetermined pressing force by a substantially opposing roller or belt, and generally by heating by a heat source such as a heater.

  The recording material S having a fixed image obtained in this way passes through the post-fixing conveyance unit 59 and is discharged as it is onto the discharge tray 500, or when it is necessary to form images on both sides, the reverse conveyance device 501 is used. The route is selected as to whether it is conveyed. The recording material S conveyed to the reverse conveying device 501 passes through the reverse conveying unit 502 and is conveyed again to the secondary transfer unit T2, and an image is formed on the back surface of the recording material S as described above. The

[Developer]
Next, the developing device 300 will be described with reference to FIGS. 3 to 5B. The developing device 300 according to the present embodiment uses a two-component developer including a nonmagnetic toner and a magnetic carrier. As shown in FIG. 3, the developing device 300 includes a developing container 301 that contains a developer, a developing sleeve 302 as a developer carrier, a regulating blade 303 as a layer thickness regulating member, and a conveying screw as a conveying member. 304, 305.

  The developing container 301 is a developer carrying member in which a part of a developing region facing the photosensitive drum 508 is opened, and a magnet roll is disposed in a non-rotating manner so as to be partially exposed to the opening. A cylindrical developing sleeve 302 is rotatably installed. The developing device 300 is pressed against the drum cartridge 200 and positioned so that the developing sleeve 302 and the photosensitive drum 508 face each other at a predetermined interval.

  The developing sleeve 302 is formed of a non-magnetic material, and rotates in the direction of the arrow in FIG. 3 during the developing operation, and holds the two-component developer in the developing container 301 in a layered manner and transports it to the developing region. Then, a developer is supplied to the photosensitive drum 508 in the development area, and the electrostatic latent image formed on the photosensitive drum 508 is developed. The developer after developing the latent image is collected in the developing container 301 as the developing sleeve 302 rotates.

  The developing container 301 includes a stirring chamber 306 and a developing chamber 307 that can store the developer, and a circulation path for circulating the developer is formed between the stirring chamber 306 and the developing chamber 307. That is, the inside of the developing container 301 is divided into a stirring chamber 306 and a developing chamber 307 by a partition wall 308, and the stirring chamber 306 and the developing chamber 307 are at both end portions in the longitudinal direction of the developing container 301 (rotational axis direction of the developing sleeve 302). Communicate with A supply port 309 (FIG. 4B) for supplying toner from a supply device (not shown) is provided at the upstream end of the stirring chamber 306 in the developer transport direction.

  Further, in the stirring chamber 306 and the developing chamber 307, conveying screws 304 and 305 are provided as conveying members for conveying the developer, respectively. Specifically, the conveying screw 304 is disposed in the stirring chamber 306, and the conveying screw 305 is disposed in the developing chamber 307. The conveying screws 304 and 305 are screws provided with spiral blades on the rotation axis. The developing sleeve 302 and the conveying screws 304 and 305 are disposed substantially parallel to each other and substantially parallel to the rotation axis direction of the photosensitive drum 508.

  The conveying screws 304 and 305 and the developing sleeve 302 are rotationally driven by a motor (not shown). As a result, the developer in the stirring chamber 306 is transported while being stirred by the transport screw 304 and moves into the developing chamber 307 via the communication portion. Further, the developer in the developing chamber 307 is conveyed in the opposite direction to the developer in the agitating chamber 306 while being agitated by the conveying screw 305, and moves into the agitating chamber 306 via the communicating portion. That is, the developer is circulated and conveyed in the developing container 301 while being agitated by the two screws of the conveying screws 304 and 305.

  Thus, the developer conveyed in the developing container 301 is carried on the developing sleeve 302. That is, the conveying screw 305 supplies the developer to the developing sleeve 302 while conveying the developer in the developing chamber 307. The developing sleeve 302 carries the developer supplied from the conveying screw 305 and conveys it to the above-described developing region. At this time, the layer thickness of the developer carried on the developing sleeve 302 is regulated by the regulating blade 303.

  In other words, the regulating blade 303 is disposed with a predetermined gap (gap) from the surface of the developing sleeve 302. Specifically, the regulating blade 303 is disposed such that the longitudinal direction thereof is along the rotational axis direction of the developing sleeve 302, and the tip thereof is close to and opposed to a part of the surface of the developing sleeve 302 along the longitudinal direction. As a result, a predetermined gap is formed between the regulating blade 303 and the developing sleeve 302.

  The developer carried and conveyed by the developing sleeve 302 passes through this predetermined gap, and thus the layer thickness (the amount of developer) is regulated. Then, the developer whose layer thickness is regulated by the regulating blade 303 is conveyed to the developing area facing the photosensitive drum 508 while being carried on the developing sleeve 302, and the electrostatic latent image on the photosensitive drum 508 is transferred as described above. Develop with toner.

[Adjustment mechanism]
As shown in FIGS. 5A and 5B, the regulating blade 303 can adjust a predetermined gap (gap) G between the developing sleeve 302 and the regulating blade 303 by an adjusting mechanism 400 as an adjusting means. . The adjustment mechanism 400 includes a screw 401 as a fixing member, a through hole 402 formed in the regulating blade 303, and a screw hole 404 formed in the fixing plate 403 fixed to the developing container 301. The through holes 402 and the screw holes 404 are formed at a plurality of locations in the longitudinal direction (five locations in the illustrated example) of the regulating blade 303, and the screws 401 are inserted and screwed respectively. That is, the plurality of screws 401 are respectively inserted into the through holes 402 of the restriction blade 303 and screwed into the screw holes 404 to fix the restriction blade 303 to the fixing plate 403.

  The through-hole 402 has a diameter larger than the shaft diameter of the screw 401, and the regulating blade 303 is inserted in the direction of the arrow in FIG. It can move in the direction of approaching or separating. When adjusting the predetermined gap G, the tightening degree of the screw 401 is finely adjusted at a plurality of locations. As a result, the gap between the regulation blade 303 and the developing sleeve 302 is adjusted to the predetermined gap G described above along the longitudinal direction of the regulation blade 303.

[Top plate member]
In this embodiment, in order to adjust the predetermined gap G (see FIG. 5B, hereinafter the same) between the regulating blade 303 and the developing sleeve 302 as described above, the following configuration is provided. First, the developing container 301 includes the top plate member 20 and the main body 21 as shown in FIGS. 3 and 4A and 4B. The main body 21 has side walls that form partition walls 308, agitation chamber 306, and developing chamber 307. The top plate member 20 is provided so as to cover the upper part of the main body portion 21. That is, the top plate member 20 is disposed above the conveying screws 304 and 305 and the developing sleeve 302 disposed in the agitating chamber 306 and the developing chamber 307 and is detachably fixed to the main body 21. The main body 21 is more rigid than the top plate member 20. In addition, although the top plate member 20 and the main-body part 21 are set as the structure which assembles separate things in this embodiment, you may form integrally.

  Such a top plate member 20 has a transmission part that transmits light at least partially. In the present embodiment, the entire top plate member 20 corresponds to the transmission part. That is, the top plate member 20 is formed of a transparent member. In the present embodiment, as shown in FIGS. 4A and 4B, the entire top plate member 20 is a transparent member. As will be described later, the top plate member 20 functions as a portion that transmits light from the outside into the developing container 301 when measuring a predetermined gap G between the developing sleeve 302 and the regulating blade 303. Therefore, it is preferable that the transmittance of the top plate member 20 is 80% or more so that a desired amount of light is transmitted into the developing container 301.

  The transmittance measurement and the spectral transmittance were measured with an automatic optical element measuring instrument ART-25 manufactured by Spectrometer Co., Ltd. Moreover, in this embodiment, in order to achieve the above-mentioned transmittance, ABS (982-X02: manufactured by Toray Industries, Inc.) which is an ABS transparent grade is adopted as the material of the top plate member 20.

[Measurement of predetermined gaps]
Next, a method for measuring the predetermined gap G between the developing sleeve 302 and the regulating blade 303 of this embodiment will be described with reference to FIG. As shown in FIG. 6, the predetermined gap measuring device 600 of the present embodiment includes a light source 601 and a camera 602. The light source 601 is disposed above the developing device 300 and irradiates light toward the top plate member 20. The camera 602 is disposed outside the developing device 300 facing a predetermined gap and in a direction orthogonal to the surface of the regulating blade 303.

  The predetermined gap G is measured after the developing device 300 is manufactured as shown in FIG. 6 and before the developer is accommodated therein. Note that the developer may be sealed in a portion other than the developing chamber 307 of the developing container 301 such as the stirring chamber 306. In the measurement, first, light is emitted from the light source 601. Then, as indicated by the arrow L1, the irradiated light passes through the top plate member 20 and goes straight, or enters the developing container 301 while being refracted by the intrinsic refractive index of the top plate member 20. The light that has passed through the top plate member 20 and entered the developing container 301 reaches the conveying screw 305 disposed in the developing chamber 307 and is reflected by the conveying screw 305 to become diffused light. Then, as indicated by the arrow L2, a part of the diffused light passes through the predetermined gap G and reaches the camera 602.

  The camera 602 captures an edge of the regulating blade 303 facing the developing sleeve 302 with this light, and thereby measures a predetermined gap G between the developing sleeve 302 and the regulating blade 303. Specifically, the camera 602 shoots the edge portions where the reflected light from the conveying screw 305 is shaded by the developing sleeve 302 and the regulating blade 303, and calculates the distance between the edges on the captured image. taking measurement. And based on this measurement result, the predetermined gap G is adjusted by the adjusting mechanism 400 described above.

  Here, in the case of the present embodiment, the conveying screw 305 as a reflecting portion is arranged so that light entering the developing container from the top plate member 20 is reflected and passes through a predetermined gap G. In other words, the light emitted from the light source 601, passing through the top plate member 20 and entering the developing container 301 is blocked by the obstacle member until it reaches the transport screw 305 disposed in the developing container 301. There is no. In other words, all the members of the developing device 300 are arranged such that light entering from the top plate member 20 can pass through the predetermined gap G between the developing sleeve 302 and the regulating blade 303 after being reflected by the conveying screw 305. At this time, the member is not present on the light passage path, or is formed of a material that allows light to pass even if it exists. The light source 601 is also arranged so that the irradiated light reaches the conveying screw 305 without passing through the top plate member 20 and being blocked by other members.

[Conveying screw]
In order to measure the predetermined gap G between the developing sleeve 302 and the regulating blade 303 as described above, the light that passes through the top plate member 20 from the light source 601 and is reflected by the conveying screw 305 to reach the camera 602. The amount of light is required to satisfy a desired amount. This is because when the amount of light reaching the camera 602 does not satisfy the desired amount, the images of the developing sleeve 302 and the regulating blade 303 taken by the camera 602 are not clear and measurement errors are likely to occur.

  Therefore, in the present embodiment, as described above, the conveying screw 305 that reflects light is white and the reflectance is increased. Specifically, the whiteness (L value) of the conveying screw 305 is set to 70 or more. The whiteness (L value) was measured with a spectrocolorimeter i1-Pro2 manufactured by X-LITE.

  The conveying screw 305 is formed by adding a white pigment to a resin so that the whole has a whiteness of 70 or more. Specifically, the conveying screw 305 uses a base material PC + AS resin (polycarbonate + acrylonitrile styrene copolymer, DN-1520B: manufactured by Teijin Limited) with a white pigment added. The conveying screw 305 may be white by another method such as applying a white paint to a screw-shaped member. Further, the conveying screw 305 may have an appearance that is not white (for example, yellow that looks white) as long as the whiteness is 70 or more.

  Furthermore, by setting the transmittance of the top plate member 20 to 80% or more, the conveying screw 305 can be irradiated with a sufficient amount of light, reflected by the conveying screw 305 having a whiteness of 70 or more, and reaching the camera 602. A sufficient amount of light can be secured. As a result, the predetermined gap G between the developing sleeve 302 and the regulating blade 303 can be measured more accurately.

  In addition, in order to achieve the above-described transmittance and spectral reflectance, the top plate member 20 may be made of polycarbonate (H2000-VR: manufactured by Mitsubishi Engineering Plastics). Further, the conveying screw 305 may employ a PC + ABS (polycarbonate + acrylonitrile butadiene styrene) resin with a white pigment added to a base material.

[Whiteness and gap measurement]
Next, experimental results obtained by examining the whiteness of the conveying screw 305 and the measured value (gap measured value) of the predetermined gap G between the developing sleeve 302 and the regulating blade 303 will be described. The developing device 300 used for the measurement is the same as that shown in FIG. Then, the whiteness (L value) of the conveying screw 305 was created at seven levels of 40, 50, 60, 70, 80, 90, and 100, and the measurement was performed by switching each. The measurement was performed using the measuring apparatus 600 shown in FIG. It was confirmed in advance that the predetermined gap G between the developing sleeve 302 and the regulating blade 303 of the developing device 300 to be measured was 270 μm by three-dimensional measurement.

The experimental results thus obtained are shown in FIG. 7 and Table 1 show an average value ± 3σ in consideration of an average value (Ave.) measured 30 times with each L-value conveying screw 305 and a standard deviation σ indicating variation in measurement. Values (Ave. + 3σ, Ave.−3σ) are described.

  As apparent from FIG. 7 and Table 1, even when the L value changed from 40 to 100, the average value was as small as 271 to 270 μm. On the other hand, the average value ± 3σ indicating the variation in measurement was 263 μm to 279 μm when the L value was 40.

  Although the predetermined gap G between the developing sleeve 302 and the regulating blade 303 is 270 μm, the measurement value of the camera 602 is shifted because the amount of reflected light reflected by the conveying screw 305 is small. If the amount of reflected light is small, the edge portions of the developing sleeve 302 and the regulating blade 303 become unclear, and a portion that is not the original edge may be erroneously detected as an edge when repeatedly measured, resulting in variations in measured values. End up.

  On the other hand, when the whiteness (L value) of the conveying screw 305 is 70 or more, the average value ± 3σ is 269 to 271 μm, and it was found that the variation can be extremely suppressed. This is because as the whiteness of the conveying screw 305 increases, the reflected light of the conveying screw 305 increases and the edges of the developing sleeve 302 and the regulating blade 303 become clear.

  In the case of the present embodiment, by setting the whiteness (L value) of the conveying screw 305 to 70 or more in this way, a sufficient amount of light reaching the camera 602 can be secured, and a predetermined amount between the developing sleeve 302 and the regulating blade 303 can be secured. Measurement of the gap G can be performed stably. In particular, in addition to setting the whiteness of the conveying screw 305 to 70 or more and setting the transmittance of the top plate member 20 to 80% or more, the amount of light reaching the camera 602 can be sufficiently secured, and a predetermined amount The gap G can be measured more accurately.

<Second Embodiment>
A second embodiment will be described with reference to FIGS. 3 and 6 with reference to FIGS. In the above-described embodiment, the entire top plate member 20 is transparent. On the other hand, in this embodiment, only a part of the top plate member 20A is used as the transmission part 8 that transmits light. Since other configurations and operations are the same as those in the first embodiment, the same reference numerals are assigned to the same configurations, and descriptions and illustrations thereof are omitted. Hereinafter, the description will focus on parts that are different from those in the first embodiment. To do.

  In the present embodiment, a part of the top plate member 20A constituting the developing container 301A of the developing device 300A is used as the transmitting portion 8 that transmits light. In FIG. 8A, three transmission parts 8 are provided in the longitudinal direction of the top plate member 20A. These three transmissive portions 8 have higher light transmittance than other portions of the top plate member 20A, and the transmittance is 80% or more. For this reason, the top plate member 20 </ b> A has the transmissive portion 8 formed as a separate member from other portions. Only the transmission part 8 may be integrally formed of a material that transmits light.

  On the other hand, the whiteness of the conveying screw 305 is set to 70 or more as in the first embodiment. And as shown in FIG.8 (b), the light which permeate | transmitted from the transmission part 8 is reflected in the three reflection parts 9 which are the positions which correspond with the three transmission parts 8 and a longitudinal direction. When the reflecting portion 9 is the shaft portion of the conveying screw 305, the reflecting portion 9 can stably reflect light into a predetermined gap. However, depending on the rotational phase of the conveying screw 305, the reflecting portion 9 may be a blade. However, even in this case, if the whiteness of the conveying screw 305 is 70 or more, it passes through a predetermined gap and reaches the camera 602. A sufficient amount of light can be secured.

  Also in the present embodiment, the conveying screw 305 is formed by adding a white pigment to the resin and has a whiteness of 70 or more as a whole, but only the reflective portion 9 may have a whiteness of 70 or more.

  In the case of this embodiment, since a part of the top plate member 20A is used as the transmission part 8, the cost can be reduced as compared with the whole top plate member as the transmission part. For example, since a transparent resin material is more expensive than a general non-transparent resin material, the cost can be reduced by narrowing the transparent range.

  Further, by providing the transmission part 8 at a plurality of locations on the top plate member 20A, a predetermined gap between the developing sleeve 302 and the regulating blade 303 can be measured at a plurality of locations in the longitudinal direction. Easy to adjust.

<Other embodiments>
In the above-described embodiment, only the conveying screw 305 has a whiteness of 70 or more, but other portions such as the partition wall 308 and the side wall of the developing container 301 may have a whiteness of 70 or more. Further, the reflecting portion may not be the conveying screw 305, and light that has entered the developing container from the top plate member 20 or the transmitting portion 8 is reflected and passes through a predetermined gap between the developing sleeve 302 and the regulating blade 303. Any member may be used as long as it is arranged. For example, depending on the irradiation direction of light from the light source 601 and the positional relationship of a predetermined gap, at least a part of the partition wall 308 and the side wall may have a whiteness of 70 or more and the conveying screw 305 may not have a whiteness of 70 or more.

  Further, the transmission part that transmits the light of the developing container may be other than the top plate member, and may be, for example, a side wall or a bottom plate part of the developing container. At this time, the configuration inside the developing container (for example, the partition wall) may be transparent. In short, a position where the light can be transmitted into the developing container and the light reflected by the reflecting portion such as the conveying screw can pass through the predetermined gap may be set as the transmitting portion.

  Further, in each of the above-described embodiments, the developing device in which the developing chamber and the stirring chamber are arranged in a substantially horizontal direction has been described. However, the present invention is such that the developing chamber and the stirring chamber have a substantially vertical direction, an oblique direction, and the like. It can also be applied to developing devices arranged side by side.

  8 ... Transmission part / 9 ... Reflection part / 20 ... Top plate member (transmission part) / 20A ... Top plate member / 300, 300A ... Developing device / 301, 301A ... Development Container / 302 ... developing sleeve (developer carrier) / 303 ... regulating blade (layer thickness regulating member) / 305 ... conveying screw (conveying member, reflector) / 400 ... adjustment mechanism (adjustment) means)

Claims (6)

A developer container that contains the developer and has a transmission part that transmits light at least in part;
A developer carrier for carrying and transporting the developer in the developer container;
A layer thickness regulating member that is disposed through the developer carrier with a predetermined gap and regulates the layer thickness of the developer carried on the developer carrier;
A transport member that feeds the developer to the developer carrier while transporting the developer in the developer container,
The conveying member has a whiteness of 70 or more.
A developing device. The transmission part has a transmittance of 80% or more.
The developing device according to claim 1, wherein: The developer container has a top plate member disposed above the developer carrier and the transport member,
The transmission part is at least a part of the top plate member,
The developing device according to claim 1, wherein The transmission part is only a part of the top plate member.
The developing device according to claim 3, wherein: Having an adjusting means capable of adjusting the predetermined gap;
The developing device according to claim 1, wherein the developing device is any one of the above. A developer container that contains the developer and has a transmission part that transmits light at least in part;
A developer carrier for carrying and transporting the developer in the developer container;
A layer thickness regulating member that is disposed through the developer carrier with a predetermined gap and regulates the layer thickness of the developer carried on the developer carrier;
A reflection part arranged so that light that has entered the developing container from the transmission part is reflected and passes through the predetermined gap, and
The reflective part has a whiteness of 70 or more.
A developing device.

Images