JP3508104B2 - Developing device and image forming machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device for developing an electrostatic latent image formed on the outer peripheral surface of a photosensitive drum into a toner image, and an image forming machine equipped with the developing device, for example, electrostatic copying. And image forming machines such as laser printers and facsimiles.

[0002]

2. Description of the Related Art In an image forming machine such as an electrostatic copying machine, an electrostatic latent image is formed on the outer peripheral surface of a photosensitive drum, and then the electrostatic latent image is developed into a toner image by a developing device. An image forming step of transferring the sheet onto a sheet such as plain paper is performed. The developing device includes a developing housing containing a developer made of, for example, one-component magnetic toner, and a developer applying unit for applying the developer in the developing housing to the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum. And a stirring and conveying means for stirring and conveying the developer in the developing housing.
The developer applying means includes a cylindrical sleeve member and a stationary magnet member disposed inside the sleeve member. In the developing housing, a first transport path extending parallel to the sleeve member and a second transport path extending parallel to the first transport path are formed by partition walls. Outside the longitudinal ends of the partition wall, communication passages that connect the first conveyance path and the second conveyance path are provided. The stirring and conveying means includes a first stirring and conveying means arranged in the first conveying path and a second stirring and conveying means.
And a second stirring / transporting unit arranged in the transporting path.
The first stirring and conveying means includes a first stirring and conveying member including a rotating shaft and a spiral blade arranged on the rotating shaft, and the second stirring and conveying means includes a rotating shaft and the spiral blade arranged on the rotating shaft. And a second stirring and conveying member including. One typical example of the layout of the sleeve member and the first stirring and conveying member is the first
The shaft center of the stirring / conveying member is disposed below the shaft center of the sleeve member.

[0003]

In the above-mentioned conventional developing device, the photosensitive drum, the sleeve member, the first agitating and conveying member and the second agitating and conveying member are rotationally driven during the development. The developer in the developing housing is circulated between the first transport path and the second transport path by the first stirring / transporting member and the second stirring / transporting member via the communication passage. The developer in the first transport path is arranged so as to cover at least a part of a lower region of the outer peripheral surface of the sleeve member facing the first transport path. Due to the rotation of the sleeve member, a part of the developer is attracted and conveyed by the magnetic force of the static magnet member arranged inside the sleeve member. The developer regulated to have a predetermined layer thickness by the developer regulation blade is jumped toward the electrostatic latent image formed on the outer peripheral surface of the photoconductor drum to perform development. The toner image formed on the outer peripheral surface of the photosensitive drum is transferred to a sheet such as plain paper and then fixed. In the above developing device, the outer diameters and pitches of most areas of the first stirring / transporting member and the second stirring / transporting member are specified to be the same as each other, but in both end regions facing the communicating path, the developer is Prevent backflow of
In order to achieve smooth circulation, a spiral blade deformed into a special shape has been used. For this reason, the structures of the first stirring and conveying member and the second stirring and conveying member are complicated, and the mold is also complicated accordingly, so that a relatively large increase in cost cannot be avoided. As a result, an image forming machine equipped with the above-mentioned developing device cannot avoid an increase in cost, and there has been a demand for improvement.

An object of the present invention is to provide a novel structure capable of preventing backflow of the developer and enabling smooth circulation of the developer with a simple structure and a low cost, and performing good development as desired. To provide a developing device.

[0005]

[0006]

According to the present invention, a developing housing for containing a developer, a developer applying means for applying the developer to the electrostatic latent image, and an agitating transfer for agitating and transferring the developer. A first transport path extending parallel to the developer applying means and a second transport path extending parallel to the first transport path are partitioned by a partition wall in the developing housing. A communication passage that is formed and that communicates the first and second conveyance paths is provided outside both ends of the partition wall, and one communication passage is between the downstream end of the first conveyance path and the upstream end of the second conveyance path. And the other communicating passage is arranged so as to communicate between the downstream end of the second conveying passage and the upstream end of the first conveying passage, and the stirring conveying means is arranged in the first conveying passage. The first stirring and transporting means and the second stirring and transporting means arranged in the second transporting path. The stage includes a first stirring and conveying member including a rotating shaft and a spiral blade arranged on the rotating shaft, and the second stirring and conveying means includes a second stirring and conveying member including a rotating shaft and the spiral blade arranged on the rotating shaft. The member includes a first stirring and transporting unit for the developer.
Material in one direction in the first transport path and in the second stirring transport section
In a developing device in which a material is conveyed in the other direction in the second conveyance path and is circulated between the first and second conveyance paths via a communication path, a pad is provided for the first and second stirring conveyance members.
And a spiral disposed on the first stirring and conveying member.
The vane and paddle means have an upstream end facing the other communication passage.
From the partial area to the downstream end area facing one communication passage
It is arranged so as to extend over the entire area and is distributed to the second stirring and conveying member.
The spiral blade installed is located at the upstream end that faces one communication passage.
From the region to the downstream end region facing the other communication passage
It is arranged so as to extend to the area and is arranged on the second stirring and conveying member.
The paddle means has an upstream end facing the one communicating passage.
Areas other than the area and facing the other communication passage
Almost all of the other area including the downstream end area
The paddle means of the first stirring and conveying member is installed from the rotating shaft.
A plurality of support portions extending outward in the radial direction, and each of the support portions
With a paddle body connected between the tips of the paddle book
The body part is located on the outside of the spiral blade in the radial direction.
To make a gap and rotate at the same angular position around the rotation axis.
It is arranged so as to extend parallel to the rolling axis and has a half of the rotation axis.
Has a width that extends in the radial direction and connects the other side of the paddle body.
Facing the upstream end region facing the road and one communicating passage
The width in the downstream end region is
The paddle hand of the second stirring and conveying member is formed to be narrower than the width.
The step is a plurality of support portions that extend radially outward from the rotation axis.
And a paddle body connected between the respective tips of the support and
And the paddle body is screwed on the radial outside of the spiral blade.
There is a gap between the outer peripheral surface of the blade and
The angular position around the rotation axis and the
In order to extend the different areas parallel to the rotation axis,
A plurality of paddles are arranged, and the paddle body extends in the radial direction of the rotating shaft.
Provided is a developing device having a wide width . One communication path of the rotating shaft of the second stirring and conveying member
Extends radially outward in the upstream end region opposite to
It is preferable that a protruding piece is provided. 1st stirring
Development carried by the sending member in the first carrying path in the one direction
The transport amount of the agent per unit time is determined by the second stirring transport member.
Unit of developer that is transported in the other direction in the second transport path
It is regulated to be larger than the transport amount per unit,
The second transport path by the upstream end region of the second stirring transport member
Transport of the developer transported in the other direction inside the unit per unit time
The feeding amount is lower than the upstream end region of the second stirring and conveying member.
The region on the flow side conveys the second conveyance path in the other direction.
Less than the transport amount of developer per unit time
Is preferred.

[0007]

[0008]

[0009]

[0010]

[0011]

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of a developing device constructed according to the present invention and a copying machine which is an image forming machine equipped with the developing device will be described with reference to the accompanying drawings. First, referring to FIG. 1, an electrostatic copying machine generally designated by the numeral 200 includes a copying machine main body 200a which is a substantially rectangular parallelepiped. A document feeder (not shown) is arranged on the upper surface of the copying machine body 200a. When the copying machine main body 200a is viewed from the front, the photoconductor is located at a position in the vicinity of one end in the left-right direction in the copying machine main body 200a, in a position near the left end in FIG. 1 and above the center in the vertical direction. A drum 201 is arranged. Around the photosensitive drum 201, a main charger 202 that uniformly charges the outer peripheral surface of the photosensitive drum 201 to a predetermined polarity, and the uniformly charged photosensitive drum 20.
Laser scanning unit LSU that forms an electrostatic latent image by scanning the outer peripheral surface of No. 1 with a laser beam corresponding to image information, and develops the electrostatic latent image formed on the outer peripheral surface of photoconductor drum 201 into a toner image. A developing device 100 (which will be described later), a transfer roller 204 that is a transfer unit that transfers the toner image developed on the outer peripheral surface of the photosensitive drum 201 to a sheet such as plain paper, and between the photosensitive drum 201 and the transfer roller 204. It is provided with a sheet transport path 206 and the like which extends substantially in the vertical direction through the transfer portion to be formed. As described later in detail, the developing device 100 includes a developing housing 2 and a toner container 2 for supplying a developer into the developing housing 2.
08 and so on.

A laser scanning unit LSU for converting image information into laser light, which is an electromagnetic wave, and irradiating the outer peripheral surface of the photosensitive drum 201 is located at a position on the opposite side of the developing housing 2 from the photosensitive drum 201 (right side in FIG. 1). position)
The developing housing 2 and the developing housing 2 are arranged in parallel at the same height. The toner container 208 is
It is arranged above the laser scanning unit LSU with a space. A partial area of the toner container 208 (specifically, an area in which a toner discharge port (not shown) is arranged) is a partial area of the developing housing 2 (specifically, a toner receiving opening described later). It is arranged so as to exist above the area where the portion 26 is arranged). Laser scanning unit LS in the copying machine body 200a
A manual paper feeding tray 210 is arranged at the right end in FIG. 1 at a position just below U, and the paper feeding portion of the manual paper feeding tray 210 is directly below the developing housing 2 and the laser scanning unit LSU. It is connected to the paper transport path 206 via a manual paper feed transport path 212 that extends substantially horizontally. Manual paper feed tray 210 and manual paper feed conveyance path 212
Paper feed cassettes 214 and 216 are vertically arranged side by side in the lower position of. Paper feed cassettes 214 and 2
The 16 paper feed units are connected to the paper transport path 206. A paper discharge tray 218 is arranged above the toner container 208. A fixing device 220 and a pair of discharge rollers 222 are arranged at the downstream end of the sheet conveyance path 206 arranged so as to extend substantially vertically.

The optical path L of the laser light emitted from the laser scanning unit LSU to the outer peripheral surface of the photosensitive drum 201 via a reflecting mirror such as a polygon mirror arranged inside.
Is the upper surface of the developing housing 2 and the toner container 208.
It is formed so as to pass through a gap between the main charger 202 and the lower surface of the main charger 202. In the embodiment, the optical path L is set so as to extend toward the outer peripheral surface of the photoconductor drum 201 while being inclined slightly above the horizontal line. A document conveyed to the document conveying device (not shown) is copied by the copying machine main body 200.
The image is read by a document reading device (not shown) provided in a and stored as image information in a storage device (not shown).
The image information stored in the storage device is converted into laser light and irradiated on the outer peripheral surface of the photosensitive drum 201 from the laser scanning unit LSU, and an electrostatic latent image is formed on the outer peripheral surface. This electrostatic latent image is developed into a toner image by the developing device 100, and the developed toner image is transferred to the paper fed and conveyed from the paper feed cassette 214 through the paper feed path 206 in the transfer section. . The toner image transferred onto the paper is fixed by the fixing device 220, and the paper on which the toner image is fixed is discharged to the paper discharge tray 218 by the discharge roller pair 222. The copying operation is repeatedly performed by the copying machine 200 as described above, and a copy is produced. In the machine shown in FIG. 1, when image information is received from the outside and the laser scanning unit LSU is operated based on the image information, the machine can be used as a laser printer. .

Next, the developing device 100 provided in the copying machine 200 will be described. 2 to 5, the developing device 100 includes a developing housing 2 for containing a developer.
(Hereinafter, simply referred to as “housing 2”). In this embodiment, the developer is composed of a known one-component magnetic toner. For example, A
The housing 2 that can be integrally formed from an appropriate synthetic resin such as BS is a bottom wall 4 and a longitudinal direction of the bottom wall 4 (see FIG.
In the left-right direction) the front side wall 6 extending upward from the front side edge
And a rear side wall 8 extending upward from the rear side edge of the bottom wall 4 in the longitudinal direction.
A front end wall 10 extending upward from the front end of the bottom wall 4 in the width direction (vertical direction in FIG. 4) and connected to the front ends of the front side wall 6 and the rear side wall 8; And a rear end wall 12 extending to the front side wall 6 and connected to the rear end of the rear side wall 8. The front side wall 6 includes a front side wall front portion 6a formed on the front side in the width direction of the housing 2 and a front side wall rear portion 6b formed on the rear side in the width direction of the housing 2, and includes the front side wall front portion 6a and the front side wall rear portion. 6b are connected by a connecting wall 6c extending in the longitudinal direction. Front side wall 6b
Is formed so as to exist at a position projecting forward in the longitudinal direction of the housing 2 with respect to the front side wall front portion 6a. Therefore, the longitudinal distance between the front side wall rear portion 6b and the rear side wall 8 is defined to be longer than the longitudinal distance between the front side wall front portion 6a and the rear side wall 8. In the housing 2, the front in the longitudinal direction is left in FIG. 4, the rear in the longitudinal direction is right in FIG. 4, the front in the width direction is upper in FIG. 4, and the rear in the width direction is lower in FIG. , Respectively.

At the foremost portion in the width direction of the housing 2, a developer applying means for applying toner to the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 201 is provided. The developer applying means includes a cylindrical sleeve member 14 extending substantially horizontally in the longitudinal direction, and a stationary permanent magnet member 16 (hereinafter, simply referred to as “magnet member 1”) disposed in the sleeve member 14.
6 "). The sleeve member 14 is made of a non-magnetic material such as aluminum and is rotatable, and the magnet member 16 is fixed at a predetermined angular position. The sleeve member 14 is fixed to the rotary shaft, and is rotationally driven counterclockwise in FIG. 2 by a driving unit (not shown). The outer peripheral surface of the sleeve member 14 is arranged so as to face the outer peripheral surface of the photosensitive drum 201 with a predetermined gap, and the outer peripheral surface of the sleeve member 14 and the photosensitive drum 201 that face each other with the gap therebetween. The outer peripheral surface cooperates with each other to define a developing area. The photosensitive drum 201 is rotationally driven clockwise in FIG. 2 by a driving unit (not shown). A developer regulating blade 18 (hereinafter simply referred to as “blade 18”), which is a developer regulating member, is provided on the outer peripheral surface of the sleeve member 14 between the front side wall front portion 6 a and the rear side wall 8 of the housing 2. On the other hand, they are arranged so as to extend in parallel with a predetermined gap. The blade 18 regulates the amount of toner held on the outer peripheral surface of the sleeve member 14 and conveyed to the developing area to a predetermined layer thickness, and is charged with a predetermined electric charge in cooperation with the rotating operation of the sleeve member 14. Let

The magnet member 16 is spaced apart from the main pole N1 arranged at the circumferential position (developing region) closest to the outer peripheral surface of the photosensitive drum 201 and on the downstream side in the rotational direction of the sleeve member 14 with respect to the main pole N1. And the carrier pole S1 (the carrier pole S1 on the downstream side with respect to the main pole N1) arranged at a distance from the carrier pole S1 and the downstream side of the carrier pole S1 and a distance near the upstream side of the blade 18. And the upstream carrier pole S2 of the blade 18 that is arranged. The main pole N1 is a magnetic pole for holding toner on the outer peripheral surface of the sleeve member 14 and stably performing jumping development with toner. The transport pole S1 is a magnetic pole for drawing the developed toner into the developing housing 10 as required. The upstream transport pole S2 of the blade 18 is a magnetic pole for holding an appropriate amount of toner in the developing housing 10, which is pumped up as described later, on the outer peripheral surface of the sleeve member 14.

Inside the housing 2, a first transfer path 20 and a second transfer path 22 are arranged. The first transport path 20 is
The sleeve member 14 is provided between the front side wall front portion 6a and the rear side wall 8.
Is arranged so as to extend substantially parallel to and horizontally along the sleeve member 14 at a substantially lower position in the rear portion in the width direction. Further, the second transport path 22 is the first transport path 2
The rear position of 0 in the width direction is arranged so as to extend parallel to the first transport path 20 and horizontally. The first transport path 20 and the second transport path 22 are formed by being partitioned by a partition wall 23. The partition wall 23 is formed integrally with the bottom wall 4 so as to extend upward from the bottom wall 4 and extend in the longitudinal direction at a predetermined height. Outside the both ends of the partition wall 23 in the longitudinal direction, communication passages 24 and 25 are provided for communicating the first conveyance passage 20 and the second conveyance passage 22 with each other. The one communication passage 24 is formed between the front end of the partition wall 23 in the longitudinal direction and the front side wall front portion 6 a of the front side wall 6. The other communication passage 25 is formed between the rear end of the partition wall 23 in the longitudinal direction and the rear side wall 8. First transport path 20 and second transport path 22
Both longitudinal end regions of the first transport path 20 and the second transport path 22 are positioned so as to face the communication paths 24 and 25. Therefore, the longitudinal lengths of the first transport path 20 and the second transport path 22 are substantially the same. ing. As will be easily understood from the following description, in FIG. 4, the right side of the first transport path 20 defines the upstream side, the left side defines the downstream side, the left side of the second transport path 22 defines the upstream side, and the right side defines the downstream side. Stipulate. Further, the one communication path 24 is provided at the downstream end of the first transport path 20 and the second transport path 2.
The two communication passages 25 are arranged so as to communicate between the two upstream end portions, and the other communication passage 25 includes the downstream end portion of the second transport passage 22 and the first transport passage 20.
Are arranged to communicate between the upstream ends of the.

Referring to FIGS. 3 to 6, the housing 2 has a toner receiving opening 26 and a toner feeding and conveying path 2.
7 are provided. The supply transport path 27 is at a position further upstream of the upstream end of the second transport path 22, and is the second transport path 2
2 is disposed on the extension in the upstream direction and the downstream end thereof is the second
It is arranged so as to be connected to the upstream end of the transport path 22. The upstream end of the supply transport path 27 is defined by the front side wall rear portion 6b, and the downstream end is the upstream end of the second transport path 22 and the front end of the one communication path 24 in the longitudinal direction (FIGS. 4 and 5).
At the left end). As is clear from the above description, the entire length obtained by adding the supply conveyance path 27 to the second conveyance path 22 extending continuously between the front side wall rear portion 6b and the rear side wall 8 in the longitudinal direction is equal to the first conveyance direction. The length of the path 20 is defined to be substantially longer than the length of the path 20 by the length of the supply transport path 27.

The receiving opening 26 is disposed at a position adjacent to the upstream end of the supply / conveyance path 27 in the rear in the width direction and inside the front side wall rear portion 6b. The upstream end of the supply transport path 27 is connected to the receiving opening 26. A toner container (not shown) is arranged in the copying machine, and the toner outlet of the toner container is detachably connected to the upper end opening of the receiving opening 26. In the receiving opening portion 26, a feeding unit that feeds the toner received from the toner container to the upstream end portion of the feeding and conveying path 27 is provided. This feeding means is composed of a feeding impeller 28 rotatably arranged in the receiving opening 26. As shown in FIG. 6, the feeding impeller 28 includes a rotating shaft 28 a and a rotating shaft 2 a.
8a and a pair of plate blades 28b extending outward in the radial direction. The rotating shaft 28a is arranged so as to extend parallel to the rotating shaft 42 of the second stirring and conveying member 40 described later. The pair of plate blades 28b includes the rotating shaft 28a.
In addition, they are arranged in symmetrical positions with an angular interval of 180 °. Inside the supply conveyance path 27, a supply conveyance means for supplying and conveying the toner fed from the receiving opening 26 by the impeller 28 to the upstream end of the second conveyance path 22 is arranged. The supply / conveyance means is constituted by a rotary shaft 42 extending in the supply / conveyance path 27 and common to the second stirring / conveying member 40, and a spiral blade 49 arranged on the rotation shaft 42 extending in the supply / conveyance path 27. Has been done. The rotating blade 42 common to the second agitating / conveying member 40 and the spiral blade 49 disposed on the rotating shaft 42 extending in the supply / conveyance path 27 constitute a toner supplying / conveying member 50. As described above, the toner supply / conveyance member 50 has the same rotation shaft 42 as the second stirring / conveyance member 40 and the spiral blade 49 disposed on the rotation shaft 42 extending in the supply / conveyance path 27.
As a result, the parts can be shared and the structure can be simplified.

Referring to FIG. 4, a stirring / conveying mechanism for stirring / conveying toner is arranged in the housing 2. The stirring / transporting mechanism includes a first stirring / transporting means arranged in the first transporting path 20 and a second stirring / transporting means arranged in the second transporting path 22. The first stirring and conveying means is composed of the first stirring and conveying member 30, and the second stirring and conveying means is composed of the second stirring and conveying member 40. As will be specifically described later, the first stirring and conveying member 30 and the second stirring and conveying member 4
When 0 is driven to rotate, the toner is unidirectionally moved in the first conveying path 20 by the first stirring and conveying member 30 (to the left in FIG. 4) and the toner is supplied to the second conveying passage 22 by the second stirring and conveying member 40. The inside is conveyed in the other direction (to the right in FIG. 4) and is circulated between the first conveyance path 20 and the second conveyance path 22 via the communication paths 24 and 25. The downstream end of the first stirring / transporting member 30 and the upstream end of the second stirring / transporting member 40 are positioned so as to face one of the communication passages 24, and the upstream end of the first stirring / transporting member 30 and the second stirring / transporting member 30 are positioned. The downstream end of the member 40 is positioned so as to face the other communication passage 25.

Referring to FIG. 7, the first agitating / conveying member 30.
Is the rotary shaft 32 and the spiral blade 3 disposed on the rotary shaft 32.
4, and a plurality of (in the embodiment, four) support portions 35a, 35b extending radially outward from the rotation shaft 32,
35c and 35d, and one paddle body 36 connected between the tips of the supporting portions 35a to 35d. One end of the rotating shaft 32 is rotatably supported by the front part 6a of the front side wall, and the other end is rotatably supported by the rear side wall 8 and one end of which is protruded into the first transport path 20. It is connected to the protrusion of the support shaft. The spiral blade 34 is formed to have a constant diameter and a constant pitch, and from the other end of the rotary shaft 32 on the upstream side facing the other communication passage 25, to the downstream side facing one communication passage 24. It is formed so as to extend over one end.

Each of the supporting portions 35a to 35d and the paddle body portion 36 constitute a paddle means. This paddle means
It is arranged so as to extend over the entire region from the upstream end region facing the other communication passage 25 to the downstream end region facing one communication passage 24. Of the support portions 35a to 35d that form a part of the paddle means, the support portions 35a and 35b arranged at both ends of the rotary shaft 32 have the axial center portions of the rotary shaft 32.
And a disc-shaped base connected to each other and a support piece formed so as to extend radially outward from a part of the outer peripheral surface of the base. Further, the support portions 35c and 35d arranged in the middle portion of the rotary shaft 32 are formed by a support piece formed so as to extend radially outward from a part of the outer peripheral surface of the rotary shaft 32 with a predetermined axial thickness. It consists of The support pieces forming the support portions 35c and 35d have a rectangular cross section and are formed such that the base end portion thereof widens in the circumferential direction toward the outer peripheral surface of the rotary shaft 32. Support portion 35a-
35d are arranged at the same angular position in the circumferential direction of the rotary shaft 32 (the same angular position around the rotary shaft 32) with an appropriate interval in the axial direction. The paddle body 36 is
The rotation shaft 32 is formed to have a rectangular cross section.
Is formed to have a predetermined width linearly extending in the radial direction and a predetermined thickness defined in the circumferential direction. Paddle body 3 having a substantially rectangular elongated plate shape as a whole
6 shows the rotating shaft 32 when viewed from the outside in the radial direction.
It is formed so as to extend linearly in line with the axis line of. The paddle body 36 is arranged so as to extend radially outside the spiral blade 34 in a straight line in parallel with the rotating shaft 32 with a gap from the outer peripheral surface of the spiral blade 34.

Referring to FIGS. 4, 5 and 7, one end 36a on the downstream side of the paddle body 36 is provided with one communication passage 24.
Is located in a region opposite to, and the other end portion 3 on the upstream side.
6b is positioned in a region facing the other communication passage 25. One end 36a of the paddle body 36 defines a downstream end region (or one end region) that is a region facing one of the communication passages 24, and the other end 36b of the paddle body 36 is the other. The upstream end region (or the other end region), which is a region facing the communication passage 25, is defined. The widths of the one end region 36a and the other end region 36b of the paddle body 36 are different from those of the other intermediate region, that is, the one end region 36.
intermediate region 36c between a and the other end region 36b
Is formed narrower than the width.

Referring to FIGS. 4, 5 and 8, the second stirring and conveying member 40 has a rotary shaft 42, a spiral blade 44 disposed on the rotary shaft 42, and the same circumferential direction on the rotary shaft 42. A plurality of (three in the embodiment) support portions 45a, 45b, and 45c that extend radially outward from the angular position (the same angular position around the rotation shaft 42) at appropriate intervals in the axial direction; One paddle body 46 connected between the tips of the parts 45a to 45c and the same angular position in the circumferential direction of the rotation shaft 42 (the other same angular position around the rotation shaft 42) from the outside in the radial direction. A plurality of (three in the embodiment) extending in the axial direction at appropriate intervals
Supports 47a, 47b and 47c, and supports 47a-4
7c and one other paddle body 48 connected between the respective tips of the 7c. The rotary shaft 42 is the rotary shaft 32.
The one end portion is rotatably supported by the front side wall rear portion 6b, and the other end portion is rotatably supported by the rear side wall 8 so that the one end portion is projected into the second transport path 22. Is connected to the protrusion of the rotary support shaft. Rotating shaft 42
Are arranged so as to extend over the entire area within the second transport path 22 and the supply transport path 27 as described above.

The spiral blades 44 are formed so as to have a constant diameter and a constant pitch, and one end of the rotary shaft 42 on the upstream side of the rotary shaft 42 facing the one communication passage 24 is connected to the other end of the rotary shaft 42. It is formed so as to extend over at least a partial region of the other end portion on the downstream side facing the passage 25.
A part of the spiral blade 44 extends to the downstream end position in the supply transport path 27.

Each of the support portions 45a to 45c and the paddle body portion 46, and each of the support portions 47a to 47c and the other paddle body portion 48 constitute a paddle means. The paddle means is arranged at least in a region other than a region facing one of the communication passages 24 (a region downstream of the region facing the one communication passage 24). The support portions 45a to 45c forming a part of the paddle means extend radially outward from a part of the outer peripheral surface of the rotary shaft 42 with a predetermined axial thickness at the upstream side position in the other region. It is composed of a formed support piece. Each of the support pieces
The cross section has a rectangular shape, and the base end portion is formed so as to widen in the circumferential direction toward the outer peripheral surface of the rotary shaft 42.
The paddle body 46 is formed to have a rectangular cross section and has a predetermined width extending linearly in the radial direction of the rotating shaft 42 and a predetermined thickness defined in the circumferential direction. There is. The paddle body 46, which has a substantially rectangular elongated plate shape as a whole, is formed so as to extend linearly in line with the axis of the rotary shaft 42 when the rotary shaft 42 is viewed from the outside in the radial direction. The paddle body 46 is arranged so as to extend linearly outside the spiral blade 44 in the radial direction with a gap from the outer peripheral surface of the spiral blade 44 and in parallel to the rotation shaft 42.

Another supporting portion 4 forming a part of the paddle means
7a to 47c are downstream positions in the other regions, and are arranged at circumferential positions of the rotary shaft 42 with an angular interval of 180 ° with respect to the support portions 45a to 45c.
Of these, the support portions 47a and 47c arranged in the upstream region at the downstream position are formed so as to extend radially outward from a part of the outer peripheral surface of the rotary shaft 42 with a predetermined axial thickness. It is composed of pieces. Each of the support pieces has a rectangular cross section and is formed such that the base end portion thereof widens toward the outer peripheral surface of the rotary shaft 42 in the circumferential direction. Further, the support portion 47b arranged at the downstream end portion at the downstream position extends radially outward from a disk-shaped base whose axial center portion is connected to the rotation shaft 42 and a part of the outer peripheral surface of the base. And a supporting piece formed so as to project.
The paddle body 48 is formed to have a rectangular cross section, and has a predetermined width extending linearly in the radial direction of the rotary shaft 42 and a predetermined thickness defined in the circumferential direction. There is. The paddle body 48 also includes a support 47.
It extends to the downstream side of b, and the extending portion is the rotation shaft 4
It is formed so as to extend directly outward in the radial direction from the outer peripheral surface of 2 with a predetermined axial width. The paddle body 48, which has a substantially rectangular elongated plate shape as a whole, is also formed so as to extend linearly in line with the axis of the rotary shaft 42 when the rotary shaft 42 is viewed from the outside in the radial direction. Is positioned at a circumferential position of the rotary shaft 42 with an angular interval of 180 ° with respect to the paddle body 46. Like the paddle body portion 46, the paddle body portion 48 extends linearly outside the spiral blade 44 in the radial direction with a gap from the outer peripheral surface of the spiral blade 44 and in parallel to the rotation axis 42. It is arranged as follows.

An upstream end of the second agitating / conveying member 40 is positioned in a region facing the communication passage 24, and another downstream end thereof is positioned in a region facing the communication passage 25. The downstream end portion of the paddle body 48 arranged at the downstream side position in the other area is positioned in the area facing the other communication passage 25. Paddle body 46
And 48 are formed to have substantially the same width as each other, and are formed to be wider than the width of the middle portion region of the paddle body portion 36 of the first stirring and conveying member 30. In the upstream end region (upstream end region of the second stirring / transporting member 40) of the rotary shaft 42 of the second stirring / transporting member 40 facing the one communication passage 24, a protrusion extending linearly outward in the radial direction. Piece 41
, Are arranged at intervals in the axial direction (see FIG. 6). Each of the projecting pieces 41 has substantially the same shape as each other, and is arranged at the same angular position as the paddle body 46. As clearly shown in FIG. 6, the protruding piece 41
Each of them has a rectangular cross section, and a base end portion thereof has a rotation shaft 42.
Is formed so as to widen toward the outer peripheral surface in the circumferential direction. The rotating shaft 42 of the second stirring and conveying member 40 and the first
The rotating shaft 32 of the agitating / conveying member 30 is configured to be rotationally driven in the clockwise direction in FIG. 2 by a driving unit (not shown) connected via the above-described rotating support shaft. The rotating shaft 28a of the feeding impeller 28 in the receiving opening 26 is drivingly connected to the rotating shaft 42 of the second stirring and conveying member 40 via the gear mechanism 29 (FIGS. 3 and 6).
reference). With this configuration, the rotating shaft 28 of the feeding impeller 28
The a is rotationally driven in the same direction (clockwise in FIG. 2) as the rotating shaft 42 of the second stirring and conveying member 40.

The rotary shaft 32 of the first stirring and conveying member 30 is arranged at substantially the same height as the lower end of the outer peripheral surface of the sleeve member 14 or at a position lower than the lower end of the outer peripheral surface of the sleeve member 14. . In the embodiment, the rotating shaft 32 of the first stirring / transporting member 30 is arranged at a position lower than the lowermost end of the outer peripheral surface of the sleeve member 14, in other words, the sleeve member 14 is disposed on the first stirring / transporting member 30. It can be said that it is arranged at a considerably high position. 2nd stirring conveyance member 4
The rotation shaft 42 of 0 is the rotation shaft 32 of the first stirring and conveying member 30.
However, in the embodiment, it is located at a slightly lower position. As described above, the rotation direction of the sleeve member 14 is defined counterclockwise in FIG. 2, and the rotation direction of the first stirring and conveying member 30 is defined clockwise in FIG. 14 and the first agitating / conveying member 30 rotate in such a manner that outer peripheral surfaces facing each other in the housing 2 are
It can be said that the opposing portions are defined so as to substantially extend upward.

In the housing 2, the second conveying path 22
The toner sensor S is disposed at a position downstream of the upstream end region facing the one communication passage 24 and in the vicinity of the upstream end region. The toner sensor S is composed of a vibration-type sensor called a pressure-bonding sensor, which itself may use a well-known configuration. When the toner is present in a predetermined amount, the vibration operation is stopped. The presence of the toner is detected, and when the toner is not present in the predetermined amount, the vibration operation is performed to detect the lack of the toner. Second with respect to the toner sensor S
At the upstream end of the paddle body 46 of the stirring and conveying member 40,
A sheet member C for cleaning the surface of the toner sensor S is provided (see FIGS. 2 to 6). The rectangular sheet member C is made of an appropriate synthetic resin, for example, Lumirror (trademark).
It can be suitably formed from a synthetic resin sheet member called. The sheet member C, which is rotated in association with the rotation of the second agitating / conveying member 40, is arranged so that the surface of the toner sensor S can be wiped, and the surface of the toner sensor S can be detected by constantly cleaning it. The function is guaranteed as required.

In FIG. 2, the chain double-dashed line indicates the upper surface of the toner contained in the housing 2 including the first transport path 20 and the second transport path 22. As shown in FIG. 2, in this embodiment, the toner is first
The agitating / conveying member 30 is accommodated in the first conveying path 20 so that the uppermost end portion of the outer peripheral surface thereof is exposed upward from the upper surface of the toner and the uppermost end portion of the outer peripheral surface of the sleeve member 14 is covered. There is. That is, as viewed in the axial direction of the sleeve member 14, the toner has an outer periphery at an outer peripheral surface of the outer peripheral surface of the outer peripheral surface of the sleeve member 14, the upper surface of which is spaced below the horizontal line passing through the axial center of the sleeve member 14. It is accommodated in the first transport path 20 to the extent that it contacts the surface. Also, the second
The toner stored in the transport path 22 is stored such that the uppermost end of the outer peripheral surface of the second stirring and transporting member 40 is exposed upward from the upper surface of the toner.

The blade 18 is a circumferential position of the outer peripheral surface of the sleeve member 14, which is spaced apart upward with respect to a horizontal line passing through the axis of the sleeve member 14 when the sleeve member 14 is viewed in the axial direction, The outer circumference of the sleeve member 14 at a circumferential position upstream of the top of the outer circumferential surface (a circumferential position facing the upper space that is located vertically above the first transport path 20 and faces the first transport path 20). It is arranged so that it can be positioned with a gap on the surface. Sleeve member 14
A partial area in the circumferential direction of the outer peripheral surface of the toner, in the embodiment, a portion in contact with the upper surface of the toner contained in the first transport path 20 and a portion facing the tip of the blade 18 with a gap. In between, it is exposed to the upper space.
The S1 pole of the magnet member 16 is the sleeve member 14
Of the sleeve member 14 in the circumferential direction facing the outer peripheral surface of the sleeve member 14 in the axial direction, the sleeve member 14 is located upstream of the vertical line passing through the axis of the sleeve member 14, and on the axis of the sleeve member 14. It is arranged at a circumferential position downstream of a horizontal line passing through the heart, in the embodiment, at a circumferential position closer to the horizontal line than the vertical line. The S2 pole is a circumferential position facing the outer peripheral surface of the sleeve member 14, and
When the sleeve member 14 is viewed in the axial direction, the sleeve member 14 is arranged at a circumferential position downstream of a horizontal line passing through the axis of the sleeve member 14 and immediately upstream of the blade 18.

In the embodiment of the copier 200 shown in FIG. 1, the paper transport path 206 has a photosensitive drum 201.
And the transfer roller 204 are arranged so as to extend substantially in the vertical direction through a transfer portion formed between the transfer roller 204 and the transfer roller 204. Due to such a layout, the sleeve member 14 of the developing device 100 is arranged on the outer peripheral surface of the photoconductor drum 201 with a predetermined gap in a region below a horizontal line passing through the axis of the photoconductor drum 201. It Since the optical path L of the laser light has to be arranged above the sleeve member 14, the upper surface of the developing housing 2 is arranged at least at a lower position where it does not interfere with the optical path L. As a result, as shown in FIGS. 1 and 2, the first agitating / conveying member 30 must be disposed considerably below the sleeve member 14.

With reference to FIGS. 2 and 4, the developing device 100.
In a state where a predetermined amount of toner is stored in the housing 2, the photosensitive drum 201, the sleeve member 14, the first stirring / transporting member 30, and the second stirring / transporting member 40 are driven by a driving unit (not shown) during development. It is driven to rotate. The toner contained in the housing 2 is unidirectionally moved in the first conveying path 20 by the first stirring and conveying member 30 (see FIG. 4).
In the left), and the second stirring and conveying member 40
Is conveyed in the other direction (to the right in FIG. 4) in the second conveyance path 22 and is circulated between the first conveyance path 20 and the second conveyance path 22 via the communication paths 24 and 25. More specifically, the toner in the first transport path 20 moves from the right side, which is the upstream side in FIG. 4, to the downstream side in the first transport path 20 due to the rotation of the spiral blade 34 of the first stirring and transporting member 30. It is conveyed while being stirred toward the left. The rotation of the paddle body 36 of the first agitating / conveying member 30 causes the toner in the first conveying path 20 to be agitated and leveled, so that the toner is allowed to flow smoothly and uniformly in the axial direction. First transport path 20
The toner in the inside is the communication passage 2 on one side facing the downstream end.
It is carried into the second transport path 22 via the 4. On the other hand,
The toner in the second transport path 22 moves in the second transport path 22 by the rotation of the spiral blade 44 of the second agitating and transporting member 40, as shown in FIG.
In the above, the paper is conveyed while being agitated from the left, which is the upstream, to the right, which is the downstream. The rotation of the paddle bodies 46 and 48 of the second agitating / conveying member 40 causes the toner in the second conveying path 22 to be agitated and leveled, so that the toner is allowed to flow smoothly and uniformly in the axial direction. By the rotation of each of the protruding pieces 41 of the second stirring and conveying member 40, the inside of the second conveying path 22 is
The toner existing in the upstream end region facing the one communication passage 24 is sufficiently loosened to prevent the toner from staying, and contributes to smooth circulation. The toner in the second transport path 22 is carried into the first transport path 20 via the other communication path 25 facing the downstream end thereof.

As described above, the sleeve member 14 and the first agitating / conveying member 30 are rotated in such a manner that their outer peripheral surfaces facing each other in the housing 2 are substantially upward in the facing portion. The positional relationship between the sleeve member 14 and the paddle body 36 is defined such that the rotational trajectory of the radially outer end of the paddle body 36 passes through a position close to the outer peripheral surface of the sleeve member 14. Therefore, a part of the toner in the first transport path 20 that has been pumped up by being lifted up by or pushed up by the upper surface of the paddle body 36 having a rectangular cross section has an outer periphery of the sleeve member 14. A face,
It is pumped up toward the outer peripheral surface on the upstream side of the blade 18, which is exposed to the first transport path 20 side.

Part of the toner drawn up by the paddle body 36 is attracted to the exposed outer peripheral surface of the sleeve member 14 by the magnetic force of the S2 pole of the magnet member 16 and conveyed. The toner regulated to a predetermined layer thickness by the blade 18 is jumped toward the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 201 in the developing area,
Development is carried out. The toner image formed on the outer peripheral surface of the photoconductor drum 201 is transferred to a sheet such as plain paper at the transfer section and then fixed by the fixing device 220 to generate a predetermined copy. As described above, although the sleeve member 14 is arranged at a considerably high position with respect to the first stirring / conveying member 30, especially the spiral blade 34 thereof, the first conveying path 2
A part of the toner in 0 is exposed by the paddle body 36 of the first agitating / conveying member 30 which is arranged on the outer side of the spiral blade 34 in the radial direction. S of the magnet member 16 located at
Since the toner is effectively pumped toward the exposed outer peripheral surface in the vicinity opposite to the two poles, the toner is replenished to the outer peripheral surface in a sufficient manner as required without any shortage or excess. It As a result, good development can be performed as desired. Further, the copying machine 200, which is an image forming machine equipped with the developing device 100 having the above-described configuration and action and effect, enables cost reduction thereof and guarantees good image output.

Both ends of the first agitating and conveying member 30 have a communication passage 2
It is located in the area opposite 4 and 25. That is, the spiral blade 34 and the paddle body 36 of the first stirring and conveying member 30 are arranged so as to exist over substantially the entire region of the first conveying path 20 from the upstream side to the downstream side, and the spiral blade 34 and the paddle body portion. Since both end portions of 36 are positioned in the regions facing the communication passages 24 and 25, the toner in the first conveyance path 20 is uniformly conveyed from its upstream end to its downstream end while being effectively stirred. At both ends of the first transport path 20 and the second transport path 22 facing the communication paths 24 and 25, the paddle body 36 is unavoidable due to its structure, although the tendency for toner to stay is unavoidable.
Since both end portions of the sleeve member are positioned in the regions facing the communication passages 24 and 25, the staying is effectively prevented, and the toner is sufficiently attached to the outer peripheral surface at both end portions of the sleeve member 14. Can be replenished. As described above, since the paddle body 36 is arranged so as to exist over the entire area including the area facing the communication passages 24 and 25, the outer peripheral surface of the sleeve member 14 is covered with new toner over its entire area. Always replenished uniformly, ensuring good development as desired. Further, the copying machine 200, which is an image forming machine equipped with the developing device 100 having the above-described configuration and action and effect, enables cost reduction thereof and guarantees good image output.

The paddle body 36 of the first agitating / conveying member 30 has a width extending in the radial direction of the rotary shaft 32, and the width of the paddle body 36 at both ends thereof is the same as that of the other intermediate portion. Since the width is narrower than the width, the backflow of the toner in the communication passages 24 and 25 is prevented, which contributes to the smooth circulation of the toner. Paddle body 3
6 is disposed so as to extend radially outward of the spiral blade 34 with a gap from the outer peripheral surface of the spiral blade 34 and extend parallel to the rotation axis. It does not hinder the stirring and transporting action of the toner in the axial direction. According to the developing device 100 of the present invention, only the paddle means including the supporting portions 35a to 35d and the paddle main body portion 36 is arranged on the first stirring and conveying member 30 having the spiral blade 34, and the magnet member is used. The minimum number of 16 magnetic poles is 3 (N1 pole, S1 pole, and S2 pole), and the toner is sufficiently secured on the exposed outer peripheral surface of the sleeve member 14 as required without shortage. Therefore, it is not necessary to provide a large number of magnetic poles as in the conventional device, the structure is simple, the manufacturing can be performed at low cost, and it is practically useful. Furthermore, unlike the conventional apparatus, it is not necessary to design a new image in consideration of the distribution of the magnetic field between the magnetic poles, which simplifies the design and also reduces the cost (the cost of the developing device 100 and the copying machine 200). Down).

The toner that has passed through the developing area is magnetized by the magnet member 1.
6 is held on the outer peripheral surface of the sleeve member 14 by the S1 pole and drawn into the housing 2, and a part of it is naturally dropped in the process of passing through a region where the magnetic force between the S1 pole and the S2 pole does not reach. It is peeled off from the outer peripheral surface of the sleeve member 14 and prepared for replenishment of new toner. As a result, the phenomenon that old toner is always attached to the outer peripheral surface of the sleeve member 14 is avoided, and toner deterioration is reliably prevented. In the above embodiment, the paddle body 36 of the first stirring and conveying member 30 is arranged so as to extend in parallel and linearly with the axis of the rotating shaft 32 when the rotating shaft 32 is viewed from the outside in the radial direction. However, in place of this, another embodiment in which it is arranged so as to extend parallel to the axis of the rotary shaft 32 and inclined in a straight line is also established. In this embodiment, by rotating the paddle body 36, in addition to the function of stirring the toner, the function of transporting the toner in the axial direction is added, and the stirring and transporting action of the first stirring and transporting member 30 is totally improved. . Further, in the above embodiment, one paddle body 36 is provided, but instead of this,
Other embodiments in which a plurality of rotary shafts 32 are arranged at intervals in the circumferential direction are also established. . According to this embodiment, the stirring function of the paddle body 36 is further improved.

Both ends of the second agitating / conveying member 40 have communication passages 2
It is located in the area opposite 4 and 25. More specifically, the spiral blade 44 disposed in the second stirring and conveying member 40 extends from the upstream end region facing the one communication passage 24 to the downstream end region facing the other communication passage 25. The paddle body portions 46 and 48, which are arranged so as to extend over the entire region and which are arranged on the second stirring and conveying member 40, are the other regions except the upstream end region facing the one communication passage 24. And is disposed over almost the entire area of the other region including the downstream end region facing the other communication passage 25 (the upstream end region facing the one communication passage 24 has no paddle means). . Due to such a configuration, the second
The toner in the transport path 22 is uniformly transported from its upstream end to its downstream end while being effectively stirred, and
Backflow of toner from the upstream end region facing the one communication passage 24 to the first transport passage 20 is prevented, and smooth circulation of toner is promoted. In the developing device 100, instead of disposing the paddle means in the upstream end region facing the one communication passage 24, the rotary shaft 4 of the second stirring / conveying member 40 is replaced.
In the upstream end region of 2, facing the one communication passage 24,
Two projecting pieces 41 extending outward in the radial direction are arranged at intervals in the axial direction. By the rotation of the projecting piece 41, the toner existing in the upstream end region of the second transport path 22 is effectively loosened, so that the toner is prevented from staying and the upstream end region facing the one communication passage 24. The backflow of the toner from the first conveyance path 20 to the first conveyance path 20 is prevented, and the smooth circulation of the toner is promoted.

The paddle means of the second agitating / conveying member 40 has angular positions around the rotary shaft 42 which are different from each other in the radial outside of the spiral blade 44 with respect to the outer peripheral surface of the spiral blade 44 and are different from each other. Two paddle body portions 46 and 48 are arranged so as to extend in parallel to the rotation axis 42 in regions that differ from each other by 180 ° in the axial direction, and the paddle body portions 46 and 48 include the paddle body portions 46 and 48. Is configured to have a width extending in the radial direction. With this configuration, the paddle body portions 46 and 48 do not hinder the axial stirring and conveying action of the toner by the spiral blade 44. If necessary, three or more paddle body portions may be provided. Since the downstream paddle body 48 is arranged so as to include the downstream end region facing the other communication passage 25, toner is prevented from staying in the downstream end region and the first transport path is provided. 20 to prevent backflow, and the other communication passage 2
The toner is smoothly carried into the first transport path 20 from the downstream end region facing 5 of FIG. As a result, smooth circulation of the toner is guaranteed.

According to the developing device 100 of the present invention, the first agitating and conveying member 30 and the second agitating and conveying member 40 are constituted by the spiral blades 32 and 42 having a normal form, and the first agitating and conveying member is also provided. No. 30 paddle means including the paddle body 36 and the second agitating / conveying member 40 paddle means including the paddle body 46 and 48, the second agitating / conveying member 40
Since each of the protruding pieces 41 of No. 1 is configured to have a simple shape, it is not necessary to use a spiral blade deformed into a special shape as in the conventional device, and accordingly, the mold is also adapted accordingly. It doesn't get complicated. As a result, it has a simple structure as a whole and can be manufactured at a low cost. Further, it is possible to prevent backflow of the toner and to smoothly circulate the toner, which is practically useful.

As described above, in the housing 2, at a position further upstream of the upstream end of the second conveying path 22,
A toner receiving opening 26 and a toner supply / transport path 27 are provided. The upstream end of the supply transport path 27 is connected to the toner receiving opening 26, and the downstream end of the supply transport path 27 is connected to the upstream end of the second transport path 22. An impeller 28, which is a feeding means for feeding the received toner to the upstream end of the supply conveyance path 27, is arranged in the reception opening 26, and the impeller 28 is provided in the supply conveyance path 27 to receive the toner. A supply / conveyance unit that supplies and conveys the toner supplied from 26 to the upstream end of the second conveyance path 22 is provided. The supply / conveyance means includes a rotary shaft 42 extending in the supply / conveyance path 27 and common to the second agitating / conveying member 40, and a spiral blade 49 arranged on the rotation shaft 42 extending in the supply / conveyance path 27. It is configured by the supply transport member 50. Housing 2
The toner is replenished to the inside based on the signal from the toner sensor S described above. At the time of toner replenishment, the first stirring / transporting member 30, the second stirring / transporting member 40, and the impeller 28 are rotationally driven by a driving unit (not shown). The toner discharged from the toner container (not shown) to the receiving opening 26 is fed by the impeller 28 to the upstream end of the toner supply / conveyance path 27. The toner fed to the upstream end of the supply transport path 27 is fed and transported to the upstream end of the second transport path 22 by the spiral blade 49 of the supply transport member 50. The toner supplied and conveyed to the upstream end of the second conveying path 22 is agitated and conveyed into the circulation path by the second agitating and conveying member 40. When the toner is replenished by a predetermined amount, the toner replenishment is stopped based on the signal from the toner sensor S.

In the developing housing 100, the first
The amount of toner conveyed per unit time by the agitating / conveying member 30 in the first conveying path 20 in the one direction is equal to the second conveying amount.
The agitating / conveying member 40 regulates the toner amount conveyed in the other direction in the second conveying path 22 to be slightly larger than the conveying amount per unit time, and the second agitating / conveying member 4
The amount of toner transported per unit time in the other direction in the second transport path 22 by the upstream end region of 0 (the upstream end region facing the one communication passage 24) is the second stirring transport member. It is important that the area of 40 of the downstream side of the upstream end area is defined to be less than the amount of toner that is transported in the other direction in the second transport path 22 per unit time. Is. The reason for this is that one communication passage 2
4, the backflow from the second transport path 22 to the first transport path 20 is surely prevented, and the amount of toner in the first transport path 20 is uniformly maintained, so that the toner is smoothly transported. Especially. If the difference in the transport amount becomes excessively large, the amount of toner in the first transport path 20 becomes non-uniform, and there is a possibility that predetermined good development cannot be performed. Further, if the difference in the carry amount becomes excessively small (for example, becomes substantially the same), the backflow may occur depending on the properties of the toner and surrounding environmental conditions (humidity, temperature, etc.).

The first agitating / conveying member 30 causes the first conveying path 2 to move.
The amount of toner conveyed per unit time in 0 in the above-mentioned one direction is determined by the second agitating / conveying member 40.
The inside of the second conveyance path 22 is made slightly larger than the conveyance amount of the toner conveyed in the other direction per unit time, and the inside of the second conveyance path 22 is defined by the upstream end region of the second stirring conveyance member 40. The transport amount of the toner transported in the other direction per unit time is transported in the other direction in the second transport path 22 by the region of the second stirring / transporting member 40 on the downstream side of the upstream end region. In order to reduce the toner transport amount per unit time, in addition to the outer diameters, pitches, and rotational speeds of the spiral blades 34 and 44 in the first stirring transport member 30 and the second stirring transport member 40, Paddle body 46, 48
Shape and size, installation area, number, angular position in the circumferential direction (phase), gap between the outer diameter of the spiral blades 34 and 44,
Numerical values such as the number of protruding pieces 41 to be installed may be set appropriately.

On the other hand, the amount of toner conveyed per unit time by the supply / conveyance member 50 in the supply / conveyance path 27 toward the upstream end of the second conveyance path 22 is determined by the first stirring / conveyance member 30 as the first conveyance amount. It is defined to be larger than the amount of toner that is transported in the one direction in the transport path 20 per unit time. To this end, by appropriately setting the outer diameter of the spiral blade 49 of the supply / transport member 50, the pitch, the number of revolutions of the supply / transport member 50, etc. relative to those of the first stirring / transport member 40, It is easily possible. In this way, by making the carrying amount by the feeding and carrying member 50 larger than the carrying amount by the first agitating and carrying member 30,
Fast toner supply is guaranteed. Further, in connection with the above replenishment of toner, the toner sensor S is
Of the toner sensor S, the responsiveness of the toner sensor S is improved and the speed and accuracy are improved. Detection of a proper toner amount is ensured.

In the above embodiment of the present invention, paddle means (supporting portions 35a to 35d and paddle body portion 36) are arranged on the first stirring / transporting member 30 and the second stirring / transporting member 40 of the developing device 100. The spiral blade 34 and the paddle means arranged in the one agitating / conveying member 30 extend in the entire region from the upstream end region facing the other communication passage 25 to the downstream end region facing one communication passage 24. And the spiral blade 44 disposed on the second stirring and conveying member 40.
Is disposed so as to extend over the entire region from an upstream end region facing one communication passage 24 to a downstream end region facing the other communication passage 25, and is disposed on the second stirring and conveying member 40. Paddle means (support portions 45a to 45c and paddle body portion 46, support portions 47a to 47c and paddle body portion 48)
Is disposed in the other region excluding the upstream end region facing the one communication passage 24 and in the other region including the downstream end region facing the other communication passage 25. The present invention is not limited to this embodiment, and other embodiments are also valid. For example, another embodiment in which the paddle means (for example, the support portions 35a to 35d and the paddle body portion 36) are provided only in the first stirring and conveying member 30 can be mentioned. In this embodiment, the spiral blades 34 and the paddle means arranged on the first stirring and conveying member 30 are arranged such that the upstream end region facing the other communicating passage 25 and the downstream end region facing one communicating passage 24. Is preferably arranged so as to extend over the entire area up to. Also in this developing device, as in the illustrated embodiment, the developer is prevented from flowing backward and the developer is smoothly circulated with a simple structure and at low cost, and good development is performed as desired. be able to. Further, according to the image forming machine equipped with such a developing device, it is possible to reduce the cost and to guarantee a good image output.

Further, for example, another embodiment in which the paddle means (for example, the support portions 45a to 45c and the paddle body portion 46, the support portions 47a to 47c and the paddle body portion 48) are provided only on the second stirring and conveying member 40. Can be mentioned. In this embodiment, the spiral blades 44 arranged in the second stirring and conveying member 40 have the entire area from the upstream end region facing the one communication passage 24 to the downstream end region facing the other communication passage 25. The paddle means provided on the second agitating / conveying member 40 so as to extend in the
4 is preferably disposed in another region excluding the upstream end region facing 4 and the downstream end region facing the other communication passage 25. Also in this developing device, as in the illustrated embodiment, the developer is prevented from flowing backward and the developer is smoothly circulated with a simple structure and at low cost, and good development is performed as desired. be able to. Further, according to the image forming machine equipped with such a developing device, it is possible to reduce the cost and to guarantee a good image output.

In the developing device according to the present invention, an embodiment in which the paddle means is provided on the first stirring / conveying member 30 and / or the second stirring / conveying member 40 is established, and the developing is performed with a simple structure and at a low cost. It is possible to prevent backflow of the developer and to smoothly circulate the developer, and to perform good development as desired. However, the achievement of such an effect is achieved especially by the first stirring and conveying member 30. This is particularly effective in the developing device in which the rotary shaft 32 is arranged at the same height position as the lower end of the sleeve member 14 or at a position lower than the lower end.

An image forming machine (for example, copying machine 200)
And the photosensitive drum 201, the main charger 202,
Laser scanning unit LSU and developing device 100
, Transfer means (eg, transfer 204), and the photosensitive drum 2
01 and the transfer means, and a paper transport path 206 that extends substantially in the up-down direction through the transfer portion, and the developing device 100 includes the developing housing 2, the developer applying means, and the developer applying means. The stirring / transporting mechanism and the toner container 208 are provided, and the rotation shaft 32 of the first stirring / transporting member 30 is disposed at substantially the same height as the lower end of the sleeve member 14 or at a position lower than the lower end. The laser scanning unit LSU is provided on the photosensitive drum 201 of the developing housing 2.
The toner container 208 is arranged in parallel with the developing housing 2 at a position opposite to the above, and the toner container 208 is arranged above the laser scanning unit LSU and is irradiated from the laser scanning unit LSU to the outer peripheral surface of the photosensitive drum 201. In the image forming machine (embodiment shown in FIG. 1) in which the optical path L of the laser light is formed so as to pass through the gap between the upper surface of the developing housing 2 and the lower surface of the toner container 208 and the main charger 202, An embodiment in which the paddle means is disposed on the first stirring / transporting member 30 and / or the second stirring / transporting member 40 is established. The developing device 100 provided in the image forming machine having the above-described layout has a simple structure and low cost, prevents backflow of the developer, and enables smooth circulation of the developer to achieve desired development. It is possible to achieve the effect that can be performed more effectively and surely, and the image forming machine equipped with such a developing device 100 can reduce the cost and obtain a good image. It guarantees the output.

The rotation directions of the sleeve member 14 and the first agitating / conveying member 30 are defined such that the outer peripheral surfaces of the developing housing 2 which face each other face substantially upward in the facing portion. Paddle means (for example, the supporting portions 35a to 35d and the paddle body 36) are arranged on the 1st stirring / transporting member 30, and when the 1st stirring / transporting member 40 is rotated, the developer in the first transporting path 20 An image forming machine having a layout in which the developing device 100 configured such that a part thereof is pumped up to the outer peripheral surface of the sleeve member 14 by the paddle means (the embodiment shown in FIG. 1)
In the case of the above, the outer peripheral surface of the sleeve member 14 arranged at a relatively high position with respect to the first stirring / conveying member 30 can be provided with a sufficient amount of developer with a simple structure and at low cost. It is possible to more effectively and surely achieve the effect that the desired replenishment can be performed and desired good development can be performed. The image forming machine not only enables cost reduction but also guarantees good image output.

Further, in the above-described embodiment according to the present invention, a so-called one-component magnetic toner made of magnetic toner is used as the developer, but the present invention is not limited to this, and the toner and the magnetic material are used. Other embodiments in which a so-called two-component magnetic toner consisting of carrier particles is used also holds.

[0054]

According to the developing device 100 of the present invention,
With a simple structure and low cost, it is possible to prevent backflow of the developer and to smoothly circulate the developer, so that good development can be performed as desired. Further, according to the image forming machine according to the present invention, and in the embodiment, the electrostatic copying machine 200,
The developing device 100, which has a simple structure and low cost, can prevent the backflow of the developer and enable the developer to circulate smoothly, and can perform good development as desired, is provided, and as a result, the cost is reduced. And guarantees a good image output.

[Brief description of drawings]

FIG. 1 is a side view showing a configuration of an embodiment of a copying machine provided with an embodiment of a developing device according to the present invention.

FIG. 2 is a lateral cross-sectional view of a main part of an embodiment of a developing device according to the present invention.

FIG. 3 is a perspective view of the developing device shown in FIG.

FIG. 4 is a plan view of the developing device shown in FIG.

FIG. 5 is an enlarged plan view showing a portion of the developing device shown in FIG.

FIG. 6 is an exploded perspective view showing a part of main constituent members included in the developing device shown in FIG.

7 is a perspective view of a first stirring / conveying member included in the developing device shown in FIG.

FIG. 8 is a perspective view of a second stirring / conveying member included in the developing device shown in FIG.

[Explanation of symbols]

2 Development housing 14 Sleeve member 16 Static permanent magnet member 18 Developer Control Member 20 First transport path 22 Second transport path 23 partitions 24 One way passage 25 Other communication passage 26 Receiving opening 27 Supply transport path 28 impeller 30 First stirring and conveying member 32 rotation axis 34 spiral blade 36 paddle body 40 Second stirring and conveying member 42 rotation axis 44 spiral blade 46, 48 Paddle body 49 spiral blade 50 supply transport member 100 developing device 200 Copier 200a Copier body 201 photoconductor drum 202 Main charger 208 toner container LSU Laser Scanning Unit L optical path S toner sensor

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hiroyuki Tode Inoue Hiroyuki Mie Prefectural Tamaki Town Noshino character Matabei 704-1 Kyocera Corporation Mie Factory Tamaki Block (56) Reference JP-A-2-84676 ( JP, A) JP 2000-98715 (JP, A) JP 7-199630 (JP, A) JP 6-19303 (JP, A) JP 5-72893 (JP, A) 64-4451 (JP, U) Actual Kaihei 7-32657 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 15/08 110 G03G 15/08 507

Claims (3)

(57) [Claims] 1. A developing housing for accommodating a developer, a developer applying means for applying the developer to an electrostatic latent image, and an agitating / conveying means for agitating and conveying the developer. A first extending parallel to the developer applying means
A transport path and a second transport path extending parallel to the first transport path are formed by partition walls, and a communication path that connects the first and second transport paths is provided outside both ends of the partition wall. The one communication passage is arranged so as to communicate between the downstream end portion of the first conveyance path and the upstream end portion of the second conveyance path, and the other communication passage is the second communication passage.
The agitating and conveying means is arranged so as to communicate between the downstream end of the conveying path and the upstream end of the first conveying path, and the agitating and conveying means is arranged in the first agitating and conveying means arranged in the first conveying path and the second conveying path. Second established
A first stirring and conveying means, the first stirring and conveying means includes a first stirring and conveying member including a rotating shaft and a spiral blade arranged on the rotating shaft, and the second stirring and conveying means is arranged on the rotating shaft and the rotating shaft. A second stirring and conveying member including a spiral blade provided is provided, and the developer is unidirectionally moved in the first conveying path by the first stirring and conveying member .
In addition, the second agitating / conveying member moves in the second conveying path in the other direction,
In a developing device that is respectively transported and circulated between the first and second transport paths via a communication path, paddle means are disposed on the first and second stirring and transporting members,
The spiral blade and the paddle means arranged on the first stirring and conveying member are arranged so as to extend over the entire area from the upstream end region facing the other communication passage to the downstream end region facing one communication passage. The spiral blade provided and arranged on the second stirring and conveying member is arranged so as to extend in the entire region from an upstream end region facing one communication passage to a downstream end region facing the other communication passage. The paddle means provided and arranged on the second stirring and conveying member includes a downstream end region that faces the other communication passage except the upstream end region that faces the one communication passage. is disposed over substantially the entire region of the other regions, paddle means in the first stirring and carrying member is a radial direction from the rotational axis
Between a plurality of support parts that extend outward and the tips of each support part
And a paddle body connected to the paddle body,
Gap the radial outside of the spiral blade with respect to the outer peripheral surface of the spiral blade
And place the same angle position around the rotation axis on the rotation axis.
It is arranged to extend in a row and in the radial direction of the rotation axis.
Has an extended width and faces the other communication passage of the paddle body
Upstream end region and a downstream end facing one communication passage
The width in the area is larger than the width in the other middle area
The paddle means of the second agitating and conveying member is also formed in a radial direction from the rotation axis.
Between a plurality of support parts that extend outward and the tips of each support part
And a paddle body connected to the paddle body,
Gap the radial outside of the spiral blade to the outer peripheral surface of the spiral blade.
Angular position around the axis of rotation, spaced apart and different from each other
And rotate the areas that differ from each other in the axial direction.
A plurality of paddles are arranged so that they extend parallel to the axis.
The developing device is characterized in that the portion has a width extending in the radial direction of the rotation axis . Of 2. A rotary shaft of the second agitation conveying member, the upstream end region facing the communication passage of one, the projecting piece extending out radially outwardly is disposed, according to claim 1, wherein Development device. 3. The amount of developer per unit time conveyed by the first agitating and conveying member in the first conveying path in the one direction is determined by the second agitating and conveying member in the second conveying path in the other direction. The developer that is defined to be larger than the transport amount of the developer transported per unit time and that is transported in the other direction in the second transport path by the upstream end region of the second stirring transport member. The transport amount per unit time of the second stirring transport member is
Than the upstream end region is defined to be less than the conveyance amount per unit of developer time by the downstream side of the area is fed through the second feed path in said other direction, and claim 1
Is the developing device according to claim 2 .