JP6589512B2 - Developing device and image forming apparatus - Google Patents

Description

  The present invention relates to a developing device and an image forming apparatus.

  In a conventional image forming apparatus, a technique described in Patent Document 1 below is known as a technique in which a developing device is provided with a member for detecting the developer concentration.

  Japanese Patent Application Laid-Open No. 2010-175944 as Patent Document 1 describes a configuration in which a toner concentration detection sensor (119) that detects the concentration of a developer from magnetic permeability is arranged in the developing device (2). In Patent Document 1, a portion corresponding to the toner concentration detection sensor (119) of the second conveying member (113) is configured by a double spiral blade (113ab), and the double spiral blade (113ab) Compared with the partial single spiral blade (113aa), it has a smaller diameter. Therefore, in Patent Document 1, a small diameter but a double helix provides a gap between the toner concentration detection sensor (119) and the double helix blade (113ab), and in the vicinity of the toner concentration detection sensor (119). The density change of the developer when the outer edge of the blade passes over the detection surface of the toner concentration detection sensor (119) is reduced without degrading the developer conveyance performance at the toner concentration detection sensor (119). ) Output variation.

JP 2010-175944 A (“0071” to “0079”, “0090” to “0099”, FIG. 6)

  In the present invention, when the developer concentration detecting member is disposed at a position where the developer is lifted upward in the direction of gravity, the developer transported by the transport portion of the upper transport member is lifted when the developer is lifted. It is a technical problem to stabilize density detection as compared with the case where it is arranged at a position to prevent.

In order to solve the technical problem, the developing device of the invention according to claim 1 comprises:
A first accommodating portion for accommodating a developer; a second accommodating portion disposed above the first accommodating portion in a gravitational direction; and disposed adjacent to the second accommodating portion. A third accommodating portion, and a accommodating portion in which the developer is accommodated,
A first rotation shaft disposed in the first storage portion; and a first transport portion that is inclined with respect to the first rotation shaft, and transports the developer in the first storage portion. A first conveying member that
A second rotation shaft disposed in the second storage portion; and a second transport portion that is inclined with respect to the second rotation shaft, and transports the developer in the second storage portion. A second conveying member that
An inflow portion that is arranged downstream of the first accommodating portion with respect to the developer conveying direction of the first conveying member, is connected to the second accommodating portion, and the developer is lifted and flows in;
A density detecting member that is disposed in the inflow portion and detects the density of the developer;
A lifting member supported by the first rotating shaft at a position corresponding to the inflow portion and lifting the developer as the first rotating shaft rotates;
With
When the radially outer end of the lifting member moves to the uppermost position as the first rotating shaft rotates, the lifting member is lifted with respect to the developer conveying direction of the first conveying member. The downstream end of the member is the same or downstream with respect to the lower end of the second transport unit in the direction of gravity in the range of one rotation of the second transport unit centered on the downstream end of the lifting member Formed to be,
It is characterized by that.

The invention according to claim 2 is the developing device according to claim 1,
The phase difference of the second transport unit with respect to the first transport unit is set to 180 ° or more and 315 ° or less .

The invention described in claim 3 is the developing device according to claim 1 or 2,
A notch portion formed at the shaft end of each rotary shaft, a part of a cylinder being cut away, and a gear for transmitting drive to each rotary shaft is supported;
With
When the notch portions are arranged at the same position with respect to the rotation direction of the respective rotation shafts, the first conveyance portion and the second conveyance portion have the same diameter and the same phase with respect to the rotation direction. Been formed,
It is characterized by that.

In order to solve the technical problem, an image forming apparatus according to a fourth aspect of the present invention provides:
An image carrier for holding the image on the surface;
The developing device according to claim 1, which develops the latent image held on the surface of the image holding body into a visible image;
A transfer device for transferring a visible image to a medium;
A fixing device for fixing the visible image transferred to the medium to the medium;
It is provided with.

According to the first, second, and fourth aspects of the present invention, when the developer concentration detecting member is disposed at a position where the developer is lifted upward in the direction of gravity, when the developer is lifted, the upper transport is performed. Density detection can be stabilized as compared with the case where the member conveyance unit is disposed at a position that prevents conveyance of the developer that is lifted.
According to invention of Claim 3, when the said notch part is arrange | positioned in the same position with respect to the rotation direction of each said rotating shaft, a 1st conveyance part and a 2nd conveyance part are the same. The positional relationship between the first conveyance unit and the second conveyance unit can be easily set as compared with the case where the diameter and the rotation direction are not formed in the same phase.

FIG. 1 is an explanatory diagram of an image forming apparatus according to a first embodiment of the present invention. FIG. 2 is a perspective view of the developing device. FIG. 3 is a partial cross-sectional view of a developer supply port portion of the developing device. 4 is an explanatory diagram of the developing device of Example 1, FIG. 4A is a cross-sectional view taken along line IVA-IVA in FIG. 3, and FIG. 4B is a cross-sectional view taken along line IVB-IVB in FIG. 5 is a cross-sectional view taken along line VV in FIG. 4B. FIG. 6 is an explanatory diagram of the phase difference in the first embodiment. FIG. 7 is an explanatory diagram of the phase difference between the transport units, FIG. 7A is an explanatory diagram when the phase difference is 0 degree, FIG. 7B is an explanatory diagram when the phase difference is 45 degrees, and FIG. 7D is an explanatory diagram when the phase difference is 135 degrees, FIG. 7E is an explanatory diagram when the phase difference is 180 degrees, and FIG. 7F is an explanatory diagram when the phase difference is 225 degrees. 7G is an explanatory diagram when the phase difference is 270 degrees, and FIG. 7H is an explanatory diagram when the phase difference is 315 degrees. FIG. 8 is an explanatory diagram of experimental results of an experimental example, FIG. 8A is an explanatory diagram when the phase difference is 0 degree, FIG. 8B is an explanatory diagram when the phase difference is 45 degrees, and FIG. 8C is a phase difference of 90 degrees 8D is an explanatory diagram when the phase difference is 135 degrees, FIG. 8E is an explanatory diagram when the phase difference is 180 degrees, FIG. 8F is an explanatory diagram when the phase difference is 225 degrees, and FIG. 8G Is an explanatory diagram when the phase difference is 270 degrees, and FIG. 8H is an explanatory diagram when the phase difference is 315 degrees.

Next, specific examples of embodiments of the present invention (hereinafter referred to as examples) will be described with reference to the drawings, but the present invention is not limited to the following examples.
In order to facilitate understanding of the following description, in the drawings, the front-rear direction is the X-axis direction, the left-right direction is the Y-axis direction, the up-down direction is the Z-axis direction, and arrows X, -X, Y, -Y, The direction indicated by Z and -Z or the indicated side is defined as the front side, the rear side, the right side, the left side, the upper side, the lower side, or the front side, the rear side, the right side, the left side, the upper side, and the lower side, respectively.
In the figure, “•” in “○” means an arrow pointing from the back of the page to the front, and “×” in “○” is the front of the page. It means an arrow pointing from the back to the back.
In the following description using the drawings, illustrations other than members necessary for the description are omitted as appropriate for easy understanding.

FIG. 1 is an explanatory diagram of an image forming apparatus according to a first embodiment of the present invention.
In FIG. 1, a copier U as an example of an image forming apparatus according to the first exemplary embodiment is an example of a recording unit, and includes a printer unit U1 as an example of an image recording apparatus. A scanner unit U2 as an example of a reading unit and an example of an image reading device is supported on the upper portion of the printer unit U1. An auto feeder U3 as an example of a document conveying device is supported on the upper portion of the scanner unit U2. The scanner unit U2 of the first embodiment supports a user interface U0 as an example of an input unit. The user interface U0 can be operated by the operator by inputting the user interface U0.

  A document tray TG1 as an example of a medium container is disposed on the upper part of the auto feeder U3. A plurality of documents Gi to be copied can be stacked and stored in the document tray TG1. A document discharge tray TG2 as an example of a document discharge unit is formed below the document tray TG1. A document transport roll U3b is disposed between the document tray TG1 and the document discharge tray TG2 along the document transport path U3a.

A platen glass PG as an example of a transparent document table is disposed on the upper surface of the scanner unit U2. In the scanner unit U2 of the first embodiment, a reading optical system A is disposed below the platen glass PG. The optical system A for reading in Example 1 is supported so as to be movable in the left-right direction along the lower surface of the platen glass PG. The reading optical system A is normally stopped at the initial position shown in FIG.
On the right side of the optical system A for reading, an imaging element CCD as an example of an imaging member is arranged. An image processing unit GS is electrically connected to the image sensor CCD.
The image processing unit GS is electrically connected to the writing circuit DL of the printer unit U1. The writing circuit DL is electrically connected to an exposure apparatus ROS as an example of a latent image forming apparatus.

  In the printer unit U1, a photosensitive drum PR as an example of an image holding member is disposed. Around the photosensitive drum PR, a charging roll CR as an example of a charging member, a developing device G, a transfer unit TU as an example of a transfer device, and a drum cleaner CLp as an example of a cleaner are arranged.

Below the transfer unit TU, paper feed trays TR1 to TR4 as examples of medium storage containers are arranged. A conveyance path SH1 extends from each of the paper feed trays TR1 to TR4. A pickup roll Rp as an example of a medium take-out member, a separation roll Rs as an example of a separation member, a conveyance roll Ra as an example of a conveyance member, and a registration roll Rr as an example of a delivery member are arranged in the conveyance path SH1. Yes.
A fixing device F having a heating roll Fh and a pressure roll Fp is disposed on the left side of the transfer unit TU. The fixing device F and the paper discharge tray TRh are connected by a discharge path SH2. The discharge path SH2 and the registration roll Rr are connected by an inversion path SH3. In the discharge path SH2, a transport roll Rb and a discharge roll Rh that can rotate in the forward and reverse directions are arranged.

(Description of image forming operation)
The plurality of documents Gi stored in the document tray TG1 sequentially passes through the document reading position on the platen glass PG and is discharged to the document discharge tray TG2.
When the automatic feeder U3 is used to automatically convey and copy a document, each document that sequentially passes through the reading position on the platen glass PG with the reading optical system A stopped at the initial position. Gi is exposed.
When the operator places the document Gi on the platen glass PG by hand, the optical system A for reading moves in the left-right direction, and the document on the platen glass PG is scanned while being exposed.
The reflected light from the original document Gi passes through the optical system A for reading and is condensed on the image sensor CCD. The image pickup device CCD converts the reflected light of the original collected on the image pickup surface into an electric signal.

The image processing unit GS converts the read signal input from the image sensor CCD into a digital image signal and outputs the digital image signal to the writing circuit DL of the printer unit U1. The writing circuit DL outputs a control signal corresponding to the input image writing signal to the exposure apparatus ROS.
The exposure apparatus ROS outputs a laser beam L and forms a latent image on the surface of the photosensitive drum PR charged by the charging roll CR. The latent image on the surface of the photosensitive drum PR is developed into a visible image by the developing device G. The transfer roll TR of the transfer unit TU transfers the visible image on the surface of the photosensitive drum PR to a recording sheet S as an example of a medium that has been transported through the transport path SH1. The visible image transferred to the recording sheet S is fixed by the fixing device F. The recording sheet S that has passed through the fixing device F is conveyed to the reverse path SH3 when duplex printing is performed, and is discharged by the discharge roll Rh when discharged to the discharge tray TRh.

(Description of developing device)
FIG. 2 is a perspective view of the developing device.
FIG. 3 is a partial cross-sectional view of a developer supply port portion of the developing device.
4 is an explanatory diagram of the developing device of Example 1, FIG. 4A is a cross-sectional view taken along line IVA-IVA in FIG. 3, and FIG. 4B is a cross-sectional view taken along line IVB-IVB in FIG.
5 is a cross-sectional view taken along line VV in FIG. 4B.
1 to 4, the developing device G is disposed to face the photosensitive drum PR in the developing region Q2. 1 to 5, the developing device G includes a developing container V as an example of a storage unit. In Example 1, the developing container V contains a two-component developer composed of a negatively chargeable toner and a positively chargeable magnetic carrier.

In FIG. 2, the developing container V has a developing container main body 1 extending in the front-rear direction. A front connection member 2 is connected to the front end of the developing container main body 1. A rear connection member 3 is connected to the rear end of the developing container main body 1. The front connection member 2 includes a front upper cylinder portion 2a and a front lower cylinder portion 2b. The rear connection member 3 has a rear upper cylinder portion 3a and a rear lower cylinder portion 3b.
In FIG. 2, a pair of supported portions 1 a and 1 a are provided on the upper portions of the front end and the rear end of the developing container main body 1. Each supported portion 1a is supported in a positioned state by a frame as an example of a frame (not shown) of the copying machine U when the developing container V is mounted inside the copying machine U.

In the upper left part of the developing container main body 1, a developing roll chamber V0 as an example of a third housing portion is formed. On the right side of the developing roll chamber V0, a supply chamber V1 as an example of a second storage unit is formed. A stirring chamber V2 as an example of a first housing portion is formed below the supply chamber V1. The supply chamber V1 is formed in the upper right portion of the developing container main body 1 and in the upper cylindrical portions 2a and 3a. Further, the stirring chamber V2 is formed in the lower right portion of the developing container main body 1 and inside the lower cylindrical portions 2b and 3b.
The developing roll chamber V0 is connected to the supply chamber V1 and the stirring chamber V2 in the front-rear direction.

A partition wall 4 is provided between the supply chamber V1 and the stirring chamber V2. The partition wall 4 divides the inside of the developing container V vertically. As an example of the inflow portion, connection ports 4a and 4b that connect the upper and lower sides are formed at the front end portion and the rear end portion of the partition wall 4.
A density sensor SN1 as an example of a developer density detection member is disposed in the rear connection port 4b.

  In FIG. 4, in the developing roll chamber V0, a developing roll R0 is supported at a position facing the photosensitive drum PR. In the supply chamber V1, a supply auger R1 as an example of a second transport member is disposed. In the stirring chamber V2, a stirring auger R2 as an example of a first transport member is disposed. In the developing device G of Example 1, a staying conveyance auger R3 as an example of a third conveyance member is disposed between the developing roll R0 and the stirring auger R2.

The developing roll R0 is a known member having a magnet roll R0a as an example of a magnet member and a developing sleeve R0b as an example of a rotating member that covers the outer surface of the magnet roll R0a.
Therefore, the developer in the developing container V circulates in the direction of the arrow Ya while being stirred by each auger R1, R2.
In FIG. 4B, the staying transport auger R3 is a member for transporting the developer staying between the stirring auger R2 and the developing roll R0.

2 and 3, a replenishing port 6 as an example of a replenishing portion is formed at the front end portion of the front upper cylindrical portion 2a. Moreover, in FIG. 2, FIG. 3, FIG. 4A, the discharge port 7 as an example of a discharge part is formed in the side surface of the front upper cylinder part 2a. The discharge port 7 according to the first exemplary embodiment is disposed upstream of the position of the replenishment port 6 in the developer transport direction, and the ratio of the new developer replenished from the replenishment port 6 being discharged immediately after replenishment is small. is doing. The supply port 6 is supplied with developer from a toner cartridge (not shown).
In FIG. 4B, a trimmer 8 as an example of a layer thickness regulating member is supported on the upper end inside the developing container V. The trimmer 8 regulates the layer thickness of the developer on the surface of the developing roll R0.

  In FIG. 2, a gear G0 is attached to the rear end portion (-X end portion) of the shaft of the developing roll R0. Gears G1, G2, and G3 are attached to the rear end portions of the shafts of the augers R1 and R2 and the stay conveyance auger R3. The gear G0 and the gear G1 are meshed with each other through an intermediate gear G4. The gears G1, G2, G3 are in mesh with each other. During the developing operation, the rotational force of the gear G0 is sequentially transmitted to the gears G4, G1, G2, and G3. At this time, the developing roll R0, the augers R1 and R2, and the staying conveyance auger R3 rotate.

2 and 4A, a discharge connection portion 21 is supported outside the discharge port 7. A front end portion of a discharge cylinder 22 as an example of a discharge path is connected to the discharge connection portion 21. A collection container 23 as an example of a developer collection unit is connected to the rear end of the discharge cylinder 22.
In FIG. 2, a discharge auger R <b> 5 as an example of a discharge conveying member is disposed inside the discharge cylinder 22.

  In FIG. 2, a gear G6 is attached to the rear end of the rotating shaft of the discharge auger R5. The gear G6 meshes with a gear G7 that meshes with the gear G2. Therefore, when the gear G2 rotates, the discharge auger R5 rotates through the gears G7 and G6. When the discharge auger R5 rotates, the excess developer discharged to the discharge tube 22 from the discharge port 7 through the discharge connection portion 21 is conveyed to the collection container 23.

  3 and 5, in the developing device G of the first embodiment, the stirring auger R2 has a stirring shaft 31 as an example of a first shaft portion. The stirring shaft 31 penetrates the stirring chamber V2 in the front-rear direction. The stirring shaft 31 supports a stirring blade 32 as an example of a first transport unit. The stirring blade 32 is formed in a spiral shape with the stirring shaft 31 as the center. On the stirring shaft 31, a lifting blade 33 as an example of a lifting member is supported at a position corresponding to the rear connection port 4b. The lifting blade 33 is formed in a plate shape extending in the axial direction. In addition, the front end of the lifting blade 33 of Example 1 is formed corresponding to the position of the front end of the connection port 4b. The length of the lifting blade 33 in the axial direction is set to a distance that the stirring blade 32 advances in the axial direction when the stirring shaft 31 rotates once, that is, a length corresponding to one pitch of the stirring blade 32.

The supply auger R1 includes a supply shaft 36 that extends in the front-rear direction as an example of the second shaft portion. A supply blade 37 as an example of a second transport unit is supported on the supply shaft 36. The supply blade 37 according to the first embodiment is formed from the rear end of the supply chamber V1 to the front connection port 4a. In the first embodiment, the supply shaft 36 is formed in the same diameter as the stirring shaft 31, and the supply blade 37 is formed in a spiral shape having the same outer diameter and the same pitch as the stirring blade 32.
In the supply auger R1 according to the first embodiment, a supply blade 38 is supported as an example of a supply conveyance unit between a position corresponding to the connection port 4a from the front end. The supply blade 38 is formed in a spiral shape whose winding direction is opposite to that of the supply blade 37.

FIG. 6 is an explanatory diagram of the phase difference in the first embodiment.
5 and 6, in Example 1, D cut portions 31 a and 36 a as examples of notches are formed on the outer ends of the stirring shaft 31 and the supply shaft 36. Each gear G1, G2 is formed with a through hole corresponding to the D cut portions 31a, 36a, and the gears G1, G2 are fixedly supported. In the first embodiment, when the angle θ formed by the surfaces of the D-cut portions 31a and 36a is 0 degrees, the stirring blade 32 and the supply blade 37 have the same phase with respect to the rotation direction, that is, the blades 32 and 37. Is set so that the phase difference between them becomes 0 degrees. That is, each of the OH of the first embodiment is configured such that a phase difference occurs between the blades 32 and 37 according to the value of the angle θ formed by R1 and R2.

FIG. 7 is an explanatory diagram of the phase difference between the transport units, FIG. 7A is an explanatory diagram when the phase difference is 0 degree, FIG. 7B is an explanatory diagram when the phase difference is 45 degrees, and FIG. 7D is an explanatory diagram when the phase difference is 135 degrees, FIG. 7E is an explanatory diagram when the phase difference is 180 degrees, and FIG. 7F is an explanatory diagram when the phase difference is 225 degrees. 7G is an explanatory diagram when the phase difference is 270 degrees, and FIG. 7H is an explanatory diagram when the phase difference is 315 degrees.
In FIG. 7, in Example 1, the phase difference of the supply blade 37 is set to 180 degrees as an example with respect to the stirring blade 32. The phase difference is desirably set to 180 ° or more and 315 ° or less. When the angle is set to 180 ° or more and 315 ° or less, as shown in FIGS. 7E to 7H, when the radially outer end of the lifting blade 33 is moved to the uppermost position, the developer conveyance of the stirring auger R2 is performed. With respect to the direction, the downstream end 33a of the lifting blade 33 is in relation to the lower end 37b of the feeding blade 37 in the gravitational direction in the range 37a of one rotation of the feeding blade 37 centered above the downstream end 33a of the lifting blade. It is set to be the same or downstream.

(Function of developing device G)
In the developing device G of Example 1 having the above-described configuration, the developer in the developing container V circulates while being agitated as the augers R1 and R2 rotate. The supply auger R1 supplies developer to the developing roll R0. The layer thickness of the developer of the developing roll R0 is regulated by the trimmer 8. The developer whose layer thickness is regulated by the trimmer 8 develops the latent image on the photosensitive drum PR into a visible image when passing through the development region Q2. The developer that has not been used in the development is returned to the inside of the developing container V from the surface of the developing roll R0. The developer returned to the developing container V is circulated again.

  When the developer is consumed in the development region Q2, the developer including toner and carrier is supplied through the supply port 6. Further, when the developer circulating inside the developing container V passes through the position of the discharge port 7, a part of the developer is discharged when the volume of the developer is higher than the height of the discharge port 7. The Therefore, the deteriorated carrier is discharged little by little through the developing container V. Therefore, the deteriorated carrier inside the developing device G is replaced little by little, and the developing performance is maintained for a long time.

  In Example 1, when the developer is consumed, the relative amount of non-magnetic toner with respect to the magnetic carrier decreases, and the toner density decreases. Then, the density sensor SN1 detects the magnetic permeability to detect the toner density. Here, in Example 1, the phase difference of the supply blade 37 with respect to the stirring blade 32 is set to 180 ° or more and 315 ° or less. Therefore, when the radially outer end of the lifting blade 33 moves to the uppermost position, the downstream end 33a of the lifting blade 33 is the same or downstream with respect to the lower end 37b of the supply blade 37 in the range 37a. Become.

  Here, in recent years, the carrier and toner are reduced in diameter, the printing speed is increased, and the rotation speeds of the augers R1 and R2 are also increased. Here, when the above-mentioned phase difference is not 180 degrees or more and 315 degrees or less, it was confirmed by experiment of an inventor that disorder | damage | failure arises in the detection result of density | concentration sensor SN1. Although the detailed principle is unknown, when the phase difference is not 180 ° or more and 315 ° or less, when the lifting blade 33 starts to lift the developer, the lower end 37b of the supply blade 37 reaches the range 33b of the lifting blade 33. ing. Therefore, the supply blade 37 is disposed at a position that prevents the developer that is lifted. Therefore, even if the developer is lifted up, it may collide with the supply blade 37 to cause the developer transportability to be sparse and dense, and may or may not come into contact with the density sensor SN1. It is done. In the state where the outer end of the lifting blade 33 is moved to the uppermost position, the lifting of the developer is completed, and the lifting of the developer is performed 90 degrees before moving to the uppermost position, that is, the lifting blade 33 is horizontal. It starts from the state of.

On the other hand, in the first embodiment, the phase difference of the supply blade 37 is set to 180 ° or more and 315 ° or less with respect to the stirring blade 32, and disturbance of the detection result of the concentration sensor SN1 is reduced. Therefore, density detection is stabilized as compared with the case where the phase difference is not 180 ° or more and 315 ° or less.
In Example 1, when the angle θ formed is 0 degree, the stirring blade 32 and the supply blade 37 are set to have the same phase with respect to the rotation direction. Therefore, the phase difference between the stirring blade 32 and the supply blade 37 can be adjusted by adjusting the angle θ formed by the surfaces of the D-cut portions 31a and 36a. Therefore, the phase difference can be easily adjusted as compared to the case where the angle θ formed is shifted from the phase in the rotation direction of the stirring blade 32 and the supply blade 37.

(Experimental example)
Next, an experiment for confirming the effect of Example 1 was performed.
The experiment was performed by modifying the developing device of Color 1000i press manufactured by Fuji Xerox Co., Ltd. The developer used was a carrier having a volume average particle diameter of 25 μm. Furthermore, the rotational speed of the augers R1 and R2 was set to 777 rpm.
The phase difference was tested at 0 °, 45 °, 90 °, 135 °, 180 °, 225 °, 270 °, and 315 ° shown in FIGS. 7A to 7H.
FIG. 8 shows the experimental results.

FIG. 8 is an explanatory diagram of experimental results of an experimental example, FIG. 8A is an explanatory diagram when the phase difference is 0 degree, FIG. 8B is an explanatory diagram when the phase difference is 45 degrees, and FIG. 8C is a phase difference of 90 degrees 8D is an explanatory diagram when the phase difference is 135 degrees, FIG. 8E is an explanatory diagram when the phase difference is 180 degrees, FIG. 8F is an explanatory diagram when the phase difference is 225 degrees, and FIG. 8G Is an explanatory diagram when the phase difference is 270 degrees, and FIG. 8H is an explanatory diagram when the phase difference is 315 degrees.
FIG. 8 is a graph in which time is taken on the horizontal axis and detected values are taken on the vertical axis.

  In FIG. 8, when the phase difference shown in FIGS. 8A to 8D is 0 ° to 135 °, the touch range of the detected value is larger than the case where the phase difference shown in FIGS. 8E to 8H is 180 ° to 315 °. It was confirmed. Therefore, it was confirmed that the detection result of the density sensor SN1 is stabilized when the phase difference is 180 ° to 315 °.

(Example of change)
As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to the said Example, A various change is made in the range of the summary of this invention described in the claim. Is possible. Modification examples (H01) to (H05) of the present invention are exemplified below.
(H01) In each of the above-described embodiments, the copying machine U as an example of the image forming apparatus is illustrated. However, the present invention is not limited to this, and can be applied to a printer, a FAX, or a multifunction machine having a plurality of functions. . Further, the image forming apparatus is not limited to a single-color developing image forming apparatus, and can be configured by a multi-color, so-called color image forming apparatus.

(H02) In the above embodiments, specific numerical values such as toner and carrier particle diameters are not limited to the numerical values exemplified in the embodiments, and can be changed according to the design, specifications, and the like.
(H03) In the above embodiment, the staying conveyance auger R3 can be omitted.

(H04) In the above-described embodiment, when the angle θ formed by the surfaces of the D-cut portions 31a and 36a is 0 degree, the stirring blade 32 and the supply blade 37 are set to have the same phase with respect to the rotation direction. However, the present invention is not limited to this. For example, when the angle θ formed by the cut-out surfaces 31b and 36b is 0 degree, the stirring blade 32 and the supply blade 37 may be configured so that the phase is different from the rotation direction.
(H05) In the above-described embodiment, it is desirable that the shafts 31 and 36 of the augers R1 and R2 have the same diameter and that the blades 32 and 37 have the same outer shape and pitch, but they can be different. is there.

4b ... inflow part,
31 ... first rotating shaft,
31a, 36a ... notch,
32 ... 1st conveyance part,
33 ... Lifting member,
33a ... downstream end of the lifting member,
36 ... second rotation axis,
37 ... second transport section,
37a: Range of one rotation of the second transport unit,
37b ... the lower end of the second transport unit in the direction of gravity,
F: Fixing device,
G: Developing device,
G1, G2 ... gears,
PR: Image carrier,
R1 ... second conveying member,
R2: First conveying member,
S ... medium,
SN1 concentration detecting member,
TU ... Transfer device,
U: Image forming apparatus,
V ... Container,
V0 ... third accommodation section,
V1 ... second housing part,
V2 ... 1st accommodating part.

Claims (4)

A first accommodating portion for accommodating a developer; a second accommodating portion disposed above the first accommodating portion in a gravitational direction; and disposed adjacent to the second accommodating portion. A third accommodating portion, and a accommodating portion in which the developer is accommodated,
A first rotation shaft disposed in the first storage portion; and a first transport portion that is inclined with respect to the first rotation shaft, and transports the developer in the first storage portion. A first conveying member that
A second rotation shaft disposed in the second storage portion; and a second transport portion that is inclined with respect to the second rotation shaft, and transports the developer in the second storage portion. A second conveying member that
An inflow portion that is disposed downstream of the first accommodating portion with respect to the developer conveying direction of the first conveying member, is connected to the second accommodating portion, and the developer is lifted and flows in;
A density detecting member that is disposed in the inflow portion and detects the density of the developer;
A lifting member that is supported by the first rotating shaft at a position corresponding to the inflow portion and lifts the developer as the first rotating shaft rotates;
With
When the radially outer end of the lifting member moves to the uppermost position as the first rotating shaft rotates, the lifting member is lifted with respect to the developer conveying direction of the first conveying member. The downstream end of the member is the same or downstream with respect to the lower end of the second transport unit in the direction of gravity in the range of one rotation of the second transport unit centered above the downstream end of the lifting member Formed to be,
A developing device. 2. The developing device according to claim 1 , wherein the phase difference of the second transport unit with respect to the first transport unit is set to 180 ° or more and 315 ° or less . A notch portion formed at the shaft end of each rotary shaft, a part of a cylinder being cut away, and a gear for transmitting drive to each rotary shaft is supported;
With
When the notch portions are arranged at the same position with respect to the rotation direction of the respective rotation shafts, the first conveyance portion and the second conveyance portion have the same diameter and the same phase with respect to the rotation direction. Been formed,
The developing device according to claim 1, wherein An image carrier for holding the image on the surface;
The developing device according to claim 1, which develops the latent image held on the surface of the image holding body into a visible image;
A transfer device for transferring a visible image to a medium;
A fixing device for fixing the visible image transferred to the medium to the medium;
An image forming apparatus comprising: