JP5659715B2 - Developer transport device and image forming apparatus - Google Patents

Description

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

In an electrophotographic image forming apparatus, a developer conveying device that conveys a developer to an image recording unit or conveys a developer collected from the image recording unit is used. As techniques relating to such a developer transport apparatus, techniques described in Patent Documents 1 to 3 below are known.
Japanese Patent Application Laid-Open No. 11-212361 as Patent Document 1 discloses a developer discharge path (5) through which deteriorated waste developer discharged from the developing machine (2) is conveyed, and a cleaner from the image carrier (1). A residual toner discharge path (6) through which the residual toner recovered by (3) is conveyed, and a waste developer and residual toner conveyed through the developer discharge path (5) and the residual toner discharge path (6) are collected. An image forming apparatus having a collection chamber (4) is described.
In Patent Document 1, a developer discharge path (5) is connected to a residual toner discharge path (6) on the way, and a waste developer in the developer discharge path (5) and a residual toner discharge path (6) are connected. A technique is described in which the residual toner merges and is conveyed to the collection chamber (4).
In Patent Document 1, the developer discharge path (5) extending in the gravitational direction is connected to the residual toner discharge path (6) extending in the horizontal direction from above, and the waste developer is applied to the residual toner conveyed in the horizontal direction. It falls in the direction of gravity and merges. Further, in another configuration of Patent Document 1, a residual toner discharge path (6) extending in the gravitational direction is connected to a developer discharge path (5) extending in the horizontal direction from the side, and the residual toner falls in the gravitational direction. In addition, the waste developer is conveyed in the horizontal direction and merged.

Japanese Patent Application Laid-Open No. 2001-83852 as Patent Document 2 discloses a developer transfer pipe (5) through which a deteriorated developer discharged from a developing machine (2) is transported, and a cleaner (3 ) And a residual toner transport pipe (6) to which the residual toner collected by the above is transported, and a merged and dropped mixing housing (8) is described.
In the drop mixing casing (8) described in Patent Document 2, the deteriorated developer that is discharged from the developer transfer pipe (5) and falls obliquely by the inner wall surface of the drop mixing casing (8) is transferred to the residual toner transport pipe (6). ) And the residual toner that has been dropped from below and merged above the drop-mixing housing (8) and dropped along the slope (81) of the drop-mixing housing (8). 8) is transported to a confluence transport path (7) that is connected to the lower end and extends in the horizontal direction. And in the fall mixing housing | casing (8) of patent document 2, the spherical body (10) is arrange | positioned in the downstream of the dropping direction, and it is periodic with the rotating auger (9) in the said confluence | merging conveyance pipe (7). , The spherical body (10) vibrates in the drop mixing housing (8) to vibrate the wall surface of the drop mixing housing (8), thereby reducing clogging of the developer.

Japanese Patent Application Laid-Open No. 2009-258315 as Patent Document 3 discloses a developer and a developing device (Gk, Pk, Pc, Pm, Py) that are collected from a photosensitive drum (Pk, Pc, Pm, Py) by a cleaner (CLk, CLc, CLm, CLy). Photoconductor transport path (102) through which the developer discharged from Gc, Gm, Gy) is transported, and intermediate transfer through which the developer collected by the cleaner (CLB) is transported from the intermediate transfer belt (B). The transfer path (121) and the drop transfer section (UH2) to which the transfer path (121) is connected are described.
In the drop transport unit (UH2) of Patent Document 3, the developer flowing in from the photoconductor transport path (102) falls along the main transport path (222f) extending downward. On the other hand, the developer flowing in from the intermediate transfer conveyance path (121) falls in the sub-conveyance path (223) provided on the upper side of the main conveyance path (222f), and the developer in the sub-conveyance path (223). It is guided to the main transport path (222f) side by the wall surface (223c) and merges above the main transport path (222f). Moreover, in the fall conveyance part (UH2) of patent document 3, the 2nd coil spring (228) arrange | positioned along the main conveyance path (222f) and the 1st coil spring (229) arrange | positioned at a sub conveyance path (223). Thus, the developer is conveyed while being broken.

Japanese Patent Laid-Open No. 11-212361 ("0013", FIG. 1, FIG. 3 to FIG. 5) JP 2001-83852 A ("0025" to "0030", "0037", FIGS. 3 and 4) JP 2009-258315 A (“0046” to “0050”, “0062” to “0063”, FIG. 5)

  An object of the present invention is to reduce clogging of a developer with a simple configuration.

In order to solve the technical problem, the developer conveying device according to claim 1,
A discharge path for the developer to which the developer including the toner discharged from the developer for developing the latent image on the surface of the image carrier and the carrier is conveyed;
A discharge path for the image carrier through which the developer recovered from the surface of the image carrier after the visible image is transferred to the medium;
A first dropping path to which the developer discharged from the image holding body discharge path is connected and dropped is connected to the image holding body discharge path, and the developer discharge path is connected to the image holding body. A drop path having a second drop path through which the developer discharged from the developer discharge path flows and falls;
A downstream discharge path connected to the downstream end of the drop path, to which the developer passing through the drop path is conveyed;
A direction in which the downstream end is connected to the first drop path from above in the direction of gravity, and the developer that has dropped inside falls toward the connection portion where the drop path and the downstream discharge path are connected Said second dropway extending to
The drop path having an inflow port through which developer discharged from the discharge path for the developing device flows, and having a space penetrating from the inflow port to the connection portion along the direction of gravity;
A downstream conveying member that is disposed in the downstream discharge path and conveys the developer that has passed through the dropping path;
The lower end is disposed in the first drop path, and the lower end thereof is connected to the downstream portion from the downstream conveying member.
In a state of being separated, reciprocatingly vibrates in the direction along the first fall path inside the first fall path.
A vibrating member;
The vibrating member disposed on an extension of the developer dropping direction from the second drop path;
It is provided with.

The invention described in claim 2 is the developer conveying device according to claim 1 ,
The falling path extends downstream from the connecting portion between the second falling path and the first falling path with respect to the inclination direction of the second falling path extending in a direction inclined with respect to the direction of gravity. The falling path whose direction is set on the opposite side across the direction of gravity; and
It is provided with.

In order to solve the technical problem, an image forming apparatus according to claim 3 is provided.
A developer for developing the latent image into a visible image;
An image carrier for holding a visible image on the surface;
A transfer device for transferring a visible image of the image carrier to a medium;
A fixing device for fixing the visible image transferred to the medium to the medium;
A developer discharge path for transporting a developer containing toner and a carrier discharged from the developer; and an image carrier discharge path for transporting the developer recovered from the surface of the image holder. ,
The developer conveying device according to claim 1 or 2 ,
It is provided with.

According to the first and third aspects of the invention, the developer dropped inside the second drop path does not fall toward the connection portion where the drop path and the downstream discharge path are connected. Thus, clogging of the developer can be reduced with a simple configuration.
According to the first aspect of the present invention, the impact of the developer colliding at the connection portion where the dropping path and the downstream discharge path are connected can be increased as compared with the configuration in which the through space is not provided. I can do it.
According to the first aspect of the present invention, the clogging of the developer can be reduced as compared with the configuration without the vibration member.
According to the first aspect of the present invention, the adhesion of the developer to the vibration member is reduced as compared with the case where the vibration member is not disposed on the extension of the developer dropping direction from the second drop path. I can do it.
According to the invention described in claim 2, the extending direction of the downstream falling path of the connection portion between the second drop path of the first drop path is not set to the opposite side across the direction of gravity Compared to the configuration, it is possible to increase the impact of the developer colliding at the connection portion where the drop path and the downstream discharge path are connected.

FIG. 1 is an overall explanatory view of an image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is an enlarged view of main parts of the image forming apparatus according to the first exemplary embodiment of the present invention, and is an enlarged view of main parts of the photosensitive drum and the belt module. FIG. 3 is a view of the image forming apparatus according to the first exemplary embodiment as viewed from the rear, and is an explanatory diagram of the waste developer conveying apparatus according to the first exemplary embodiment. FIG. 4 is a cross-sectional view of the discharge path of the waste developer conveyance device of the first embodiment. 5A and 5B are explanatory diagrams of the connection portion of the discharge path, FIG. 5A is a diagram corresponding to the sectional view taken along the line VA-VA in FIG. 3, FIG. 5B is a diagram corresponding to the sectional view taken along the line VB-VB in FIG. Is a diagram corresponding to the sectional view taken along the line VC-VC in FIG. 3, and FIG. 5D is a diagram corresponding to the sectional view taken along the line VD-VD in FIG. FIG. 6 is an enlarged view of a main part of FIG. 4, and is an explanatory diagram of a falling path of the first embodiment. FIG. 7 is a diagram corresponding to FIG. 6 and is an operation explanatory diagram of the first embodiment. FIG. 8 is an explanatory view of a conventional dropping path, FIG. 8A is an explanatory view of a connecting portion between the dropping path and a downstream conveying path, and FIG. 8B corresponds to a sectional view taken along line VIIIB-VIIIB in FIG. 8C is an explanatory diagram subsequent to FIG. 8B, and FIG. 8D is an explanatory diagram subsequent to FIG. 8C. FIG. 9 is an explanatory diagram of a falling path of the second embodiment and corresponds to FIG. 6 of the first embodiment.

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 heading 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 overall explanatory view of an image forming apparatus according to Embodiment 1 of the present invention.
In FIG. 1, an image forming apparatus U according to the first embodiment is configured by a copying machine. The image forming apparatus U includes an image forming apparatus body U1 having a platen glass PG as an example of a transparent document reading surface at an upper end, and an automatic document feeder U2 placed on the platen glass PG of the image forming apparatus body U1. And have. The automatic document feeder U2 includes a document feed tray TG1 on which a plurality of documents Gi to be copied are stacked as an example of a document supply unit. A plurality of documents Gi stacked on the document feed tray TG1 are sequentially conveyed to a preset document reading position on the platen glass PG, and discharged to a document discharge tray TG2 as an example of a document discharge unit. The rear end portion of the automatic document feeder U2 is supported by an opening / closing shaft (not shown) extending in the left-right direction so as to be rotatable with respect to the image forming apparatus main body U1. When placed on the glass PG, it is rotated upward.

The image forming apparatus main body U1 has a user interface UI as an example of an operation unit through which a user inputs an operation command signal.
Below the platen glass PG on the upper surface of the image forming apparatus main body U1, a scanner unit U1a as an example of a document reading apparatus is disposed. The scanner unit U1a includes an exposure system registration sensor Sp disposed at a platen registration position as an example of an exposure reference position and an exposure optical system A as an example of an exposure system detection member. The exposure optical system A is controlled to move and stop by a detection signal from the exposure system registration sensor Sp, and is always stopped at a home position as an example of an initial position. The reflected light from the document Gi passing through the document reading position on the upper surface of the platen glass PG by the automatic document feeder U2 or the reflected light from the document Gi manually placed on the platen glass PG is used as the exposure optical system A. Are converted into electrical signals of R: red, G: green, and B: blue by the solid-state imaging device CCD, and input to the image processing unit GS.

  The image processing unit GS temporarily converts the RGB electrical signals input from the solid-state imaging device CCD into image data as an example of K: black, Y: yellow, M: magenta, C: cyan image information. Then, the image data is output to a laser drive circuit DL as an example of a latent image formation drive circuit as image data for forming a latent image at a preset time. The laser drive circuit DL outputs a drive signal to the latent image forming apparatus ROS according to the input image data.

FIG. 2 is an enlarged view of main parts of the image forming apparatus according to the first exemplary embodiment of the present invention, and is an enlarged view of main parts of the photosensitive drum and the belt module.
1 and 2, the photosensitive drum PR as an example of the first image carrier rotates in the direction of the arrow Ya. The surface of the photosensitive drum PR is neutralized by the static eliminator JR and uniform by the charger CC. Then, at the latent image writing position Q1, it is exposed and scanned with a laser beam L as an example of latent image writing light of the latent image forming device ROS to form an electrostatic latent image. When a color image as an example of a multicolor image is formed, an electrostatic latent image corresponding to an image of four colors of K: black, Y: yellow, M: magenta, and C: cyan is formed on the surface of the photosensitive drum PR. When a monochrome image as an example of a monochromatic image is formed sequentially, only the electrostatic latent image corresponding to the K: black image is formed on the surface of the photosensitive drum PR.

In FIG. 1, the surface of the photosensitive drum PR on which the electrostatic latent image is formed rotates and moves sequentially through the development area Q2 and the primary transfer area Q3.
On the right side of the photosensitive drum PR, a rotary developing device G as an example of a rotary developing device is disposed in the developing region Q2 so as to face the photosensitive drum PR. The developing device G has four color developing devices GK, GY, GM, GC of K: black, Y: yellow, M: magenta, C: cyan, and the developing devices GK, GY, GM, GC. Are sequentially moved to the developing region Q2 as the developing rotation axis Ga of the developing device G rotates. The developing units GK, GY, GM, GC have a developing roll GR as an example of a developer holding member that conveys the developer to the developing region Q2, and are on the photosensitive drum PR that passes through the developing region Q2. The electrostatic latent image is developed into a toner image Tn as an example of a visible image. In each of the developing units GK, GY, GM, and GC, a new developer is supplied to each of the developing units GK, GY, GM, and GC from a toner cartridge Tck, Tcy, Tcm, and Tcc as an example of a developer container. It is configured to be.

Here, in each of the developing devices GK to GC of the developing device G, a so-called two-component developer containing toner and carrier is used, and the toner density of the developing devices GK to GC is determined from the toner cartridges Tck to Tcc. In other words, a so-called high-density developer having a higher toner ratio than the toner is supplied. Thereby, in each of the developing units GK to GC, the high concentration developer containing a small amount of carrier is replenished, and the developer including the carrier having deteriorated charging property is discharged little by little from the developing units GK to GC. The carrier is exchanged. At this time, the developer discharged from each of the developing units GK to GC is transported to a transport path Ga1 provided along the center of the developing rotation axis Ga, and a later-described waste developer provided later It is transported to the transport device UH.
In the rotary developing device G, a technique for discharging and transporting the deteriorated developer while exchanging the carrier little by little is known in the art. For example, JP 2000-112229 A, JP Since it is described in Japanese Patent Laid-Open No. 2000-131942, etc., detailed description thereof is omitted.

1 and 2, a belt module BM as an example of an intermediate transfer device is disposed below the photosensitive drum PR. The belt module BM is an example of an intermediate transfer member, and includes an intermediate transfer belt B as an example of a second image carrier. The intermediate transfer belt B is disposed to face the photosensitive drum PR in the primary transfer region Q3. The intermediate transfer belt B includes a belt drive roll Rd as an example of an intermediate transfer member drive member, a tension roll Rt as an example of an intermediate transfer member tension member, a walking roll Rw as an example of a meandering prevention member, and an intermediate transfer member. Belt support roll (Rd, Rt, Rw, Rf, T2a) as an example of an intermediate transfer member support member including an idler roll Rf as an example of a body driven member and a backup roll T2a as an example of a secondary transfer counter member And a primary transfer roll T1, which is an example of a first transfer device and is an example of a primary transfer member, and is rotatably supported.
The intermediate transfer belt B, the belt driving roll Rd, the tension roll Rt, the walking roll Rw, the idler roll Rf, the backup roll T2a, and the primary transfer roll T1 constitute the belt module BM of the first embodiment. Has been.

When a color image is formed, an electrostatic latent image of the first color is formed at the latent image writing position Q1, and a toner image Tn of the first color is formed in the development region Q2. When the toner image Tn passes through the primary transfer region Q3, the toner image Tn is primarily transferred onto an intermediate transfer belt B as an example of a medium to be transferred by the primary transfer roll T1. Thereafter, in the same manner, the toner images Tn of the second color, the third color, and the fourth color are sequentially superimposed and primarily transferred onto the intermediate transfer belt B to which the toner image Tn of the first color has been transferred. A color multiple toner image is formed on the intermediate transfer belt B. When a monochrome image is formed, only the K: black developing unit GK is used, and a monochromatic toner image is primarily transferred onto the intermediate transfer belt B. After the primary transfer, the surface of the photosensitive drum PR is neutralized by a static eliminator JR and cleaned by a photosensitive cleaner CL1 as an example of a first image carrier cleaner.
The photoreceptor cleaner CL1 has a cleaning brush CL1a as an example of a first cleaning member and a cleaning blade CL1b as an example of a second cleaning member, and cleans the surface of the photoreceptor drum PR. As an example of the developer, residual toner remaining on the surface of the photosensitive drum PR is collected. The present residual agent collected by the cleaning members CL1a and CL1b is transferred to a later-described waste developer conveying device UH provided behind by an auger CL1c as an example of a conveying member provided inside the photoreceptor cleaner CL1. Be transported.

In FIG. 1, a secondary transfer roll T2b as an example of a secondary transfer member is disposed below the backup roll T2a so as to be movable between a position separated from the backup roll T2a and a position in contact with the backup roll T2a. ing. A secondary transfer region Q4 is formed by a contact region between the backup roll T2a and the secondary transfer roll T2b. The backup roll T2a is supplied with a secondary transfer voltage having a polarity opposite to the charging polarity of the toner used in the developing device G from a power supply circuit E, and the power supply circuit E is controlled by a controller C as an example of a control unit. . The backup roll T2a and the secondary transfer roll T2b constitute a secondary transfer device T2 as an example of the second transfer device of the first embodiment.
The primary transfer roll T1, the intermediate transfer belt B, the secondary transfer device T2, and the like constitute a transfer device T1 + T2 + B of the first embodiment.

The recording sheet S as an example of the medium stored in the paper feed trays TR1 and TR2 as an example of the medium supply unit is taken out by a pickup roll Rp as an example of a medium take-out member at a preset time, and the medium is rolled. The sheets are separated one by one by a separating roll Rs as an example of a member and conveyed to a sheet supply path SH1 as an example of a medium supply path. The recording sheet S supplied to the sheet supply path SH1 is conveyed to a registration roll Rr as an example of a medium conveyance timing adjustment member by a plurality of conveyance rolls Ra as an example of a medium conveyance member. The recording sheet S conveyed to the registration roll Rr is used as an example of a medium guide member before transfer in time for the primary transfer multiple toner image or single color toner image to move to the secondary transfer area Q4. The sheet is conveyed from the pre-transfer sheet guide SG1 to the secondary transfer area Q4. In the secondary transfer region Q4, the secondary transfer unit T2 secondary-transfers the toner image on the intermediate transfer belt B onto the recording sheet S. The intermediate transfer belt B after the secondary transfer is an example of an intermediate transfer member cleaning device, and is cleaned by a belt cleaner CL2 as an example of a second image carrier cleaning device to remove residual toner.
The belt cleaner CL2 has a cleaning brush CL2a as an example of a first cleaning member and a cleaning blade CL2b as an example of a second cleaning member, and cleans the surface of the intermediate transfer belt B, Collect residual toner and paper dust. The present residual agent collected by the cleaning members CL2a and CL2b is conveyed to a later-described waste developer conveying device UH provided behind by an auger CL2c as an example of a conveying member provided inside the belt cleaner CL2. Is done.

The secondary transfer roll T2b and the belt cleaner CL2 are disposed so as to be separated from and in contact with the intermediate transfer belt B. When a color image is formed, an unfixed toner image of the final color is applied to the intermediate transfer belt B. It is separated from the intermediate transfer belt B until the primary transfer.
The recording sheet S on which the toner image has been secondarily transferred is conveyed to the fixing region Q5 by a post-transfer sheet guide SG2 as an example of a medium guide member after transfer and a sheet conveyance belt BH as an example of a medium adsorption conveyance member. . The fixing region Q5 is a region where a heating roll Fh as an example of a heating member of the fixing device F and a pressure roll Fp as an example of a pressure member are in pressure contact, and the recording sheet S passing through the fixing region Q5 is fixed. Heat fixing is performed by the apparatus F.
The developing device G, the photosensitive drum PR, the charger CC, the transfer device T1 + T2 + B, the fixing device F, and the like constitute the image recording unit U3 of the first embodiment.

The recording sheet S on which the toner image is fixed is conveyed through a sheet discharge path SH2 on the downstream side of the fixing area Q5 as an example of a medium discharge path, and is discharged from a medium discharge port by a sheet discharge roll Rh as an example of a medium discharge member. The sheet is discharged from a sheet discharge port Rha as an example. The recording sheet S discharged from the sheet discharge port Rha is discharged and stacked on a discharge tray TRh as an example of a medium discharge portion.
A sheet reversing path SH3 as an example of a medium reversing path is connected to the sheet discharging path SH2 on the upstream side of the sheet discharging roll Rh, and a connection destination of the sheet discharging path SH2 and the sheet reversing path SH3 is connected to a conveyance destination. A switching gate GT1 as an example of the switching member is provided. The switching gate GT1 selectively switches the recording sheet S conveyed through the sheet discharge path SH2 to either the sheet discharge roll Rh side or the sheet reversing path SH3 side.

  A sheet circulation path SH4 as an example of a medium circulation path is connected to the sheet reversal path SH3, and a connection portion between the sheet reversal path SH3 and the sheet circulation path SH4 is an example of a second transport destination switching member. Switching gate GT2 is provided. The switching gate GT2 passes the recording sheet S conveyed through the sheet reversing path SH3 from the switching gate GT1 as it is, and the recording sheet S that has been once passed and then fed back to the sheet circulation path SH4 side. Let go. The recording sheet S conveyed to the sheet circulation path SH4 is retransmitted to the secondary transfer area Q4 through the sheet supply path SH1. A sheet conveying path SH as an example of a medium conveying path is configured by the elements indicated by the symbols SH1 to SH4. Further, a sheet conveying device SU as an example of a medium conveying device is configured by the elements indicated by the symbols Rp, Rs, Rr, Ra, SG1, SG2, and BH.

(Description of Waste Developer Conveying Device UH)
FIG. 3 is a view of the image forming apparatus according to the first exemplary embodiment as viewed from the rear, and is an explanatory diagram of the waste developer conveying apparatus according to the first exemplary embodiment.
FIG. 4 is a cross-sectional view of the discharge path of the waste developer conveyance device according to the first embodiment.
5A and 5B are explanatory diagrams of the connection portion of the discharge path, FIG. 5A is a diagram corresponding to the cross-sectional view taken along the line VA-VA in FIG. 3, FIG. Is a diagram corresponding to the sectional view taken along the line VC-VC in FIG. 3, and FIG. 5D is a diagram corresponding to the sectional view taken along the line VD-VD in FIG.
In FIG. 3, a waste developer transport device UH as an example of a developer transport device is supported behind the image forming apparatus U of the first embodiment via a frame (not shown).
3, 4, and 5 </ b> A, the waste developer transport device UH includes a photoreceptor discharge cylinder 1 that extends rearward from the rear surface of the photoreceptor cleaner CL <b> 1 as an example of a discharge cylinder of the photoreceptor cleaner CL <b> 1. The auger CL1c is arranged inside the photosensitive member discharge cylinder 1.

As an example of a discharge path, a front end of a relay path 2 that extends rearward is connected to a lower part of the rear end of the photoconductor discharge cylinder 1, and the developer conveyed by the auger CL1c flows therein. An auger 3 as an example of a transport member that transports the developer in the relay path 2 backward is disposed inside the relay path 2. The rear end of the relay path 2 is connected to an upper portion of an inclined path 4 that extends obliquely rearward to the right as an example of a discharge path. An auger 6 as an example of a conveying member that conveys the developer in the inclined path 4 from the upper left to the lower right is disposed inside the inclined path 4.
3, 4, and 5 </ b> B, the waste developer transport device UH includes a belt discharge cylinder 11 that extends rearward from the rear surface of the belt cleaner CL <b> 2 as an example of a discharge cylinder of the belt cleaner CL <b> 1. An auger CL2c is arranged inside the belt discharge cylinder 11. The belt discharge cylinder 11 is connected to the lower part of the rear end of the belt discharge tube 11 as an example of a discharge path. The front end of a combined flow path 12 extending rearward is connected, and the developer conveyed by the auger CL2c flows in. Further, the lower right end of the inclined path 4 is connected to a central portion in the front-rear direction of the combined flow path 12, and the developer conveyed by the auger 6 merges. An auger 13 as an example of a conveying member that conveys the developer in the combined flow path 12 to the rear is disposed inside the combined flow path 12.

  The photosensitive member discharge cylinder 1, the relay path 2, and the inclined path 4 constitute a photosensitive member discharge path 1 + 2 + 4 as an example of the first image carrier discharge path of the first embodiment. Further, the belt discharge cylinder 11 and the combined flow path 12 constitute a discharge path 11 + 12 for an intermediate transfer belt as an example of a discharge path for a second image carrier in the first embodiment. The developer discharge path 14 as an example of the image carrier discharge path of the first exemplary embodiment is configured by the photoreceptor discharge path 1 + 2 + 4 and the intermediate transfer belt discharge path 11 + 12. In the recovered developer discharge path 14, the developer recovered from the surface of the photosensitive drum PR after the toner image Tn is transferred to the intermediate transfer belt B and the toner image Tn is transferred to the recording sheet S. The developer recovered from the surface of the intermediate transfer belt B is conveyed.

3, 4, and 5 </ b> C, the waste developer transport device UH, which is an example of a discharge cylinder of the development device G, extends in the front-rear direction and is disposed in the development rotation shaft Ga, and the transport path. It has a developing discharge cylinder 21 constituting Ga1. An auger 22 as an example of a conveying member that conveys the developer discharged from the developing units GK to GC to the rear is disposed inside the developing discharge cylinder 21. A development inclined path 23 is connected to the rear end portion of the development discharge cylinder 21 as an example of a discharge path. The development inclination path 23 extends in a direction inclined downward from the rear end of the development discharge cylinder 21. The developer that has been transported to the auger 22 and has flowed into the development ramp 23 is dropped and transported in the development ramp 23.
The developer discharge cylinder 21 and the development inclined path 23 constitute a discharged developer discharge path 24 as an example of a discharge path for the developing device of the first embodiment. In the discharged developer discharge path 24, the developer including the toner discharged from the developing units GK to GC and the carrier is conveyed.

FIG. 6 is an enlarged view of a main part of FIG. 4, and is an explanatory diagram of a falling path of the first embodiment.
3, 4, and 6, the rear end of the recovered developer discharge path 14 and the lower end of the discharged developer discharge path 24 are connected to a drop path 31 disposed below the rear of the developing device G. It is connected.
In FIG. 6, a first inflow port 32 is formed at the upper left portion of the dropping path 31, and the rear end of the relay path 12 of the recovered developer discharge path 14 is connected. A first drop cylinder 33 as an example of a first drop path body is formed below the first inlet 32. The first dropping cylinder 33 is formed in a shape that becomes narrower as it goes down and inclines to the right as it goes down. The first dropping cylinder 33 has a lower left inner surface 33a in the gravity direction and a right inner surface 33b in the gravity direction. Below the first dropping cylinder 33, a discharge port 34 for a dropping path through which the developer is discharged is formed.
The first inflow path 32 of the first embodiment is configured by the first inflow port 32, the first drop cylinder 33, and the discharge port 34 of the drop path.

A coil spring 37 having a shape in which a wire is spirally wound is disposed in the first drop path 36 as an example of a vibrating member. The upper end of the coil spring 37 is supported as an example of a rotating shaft with a play on a crankshaft 38 that is rotatably supported by a wall in the front-rear direction. Therefore, when the crankshaft 38 rotates, the coil spring 37 reciprocates in the direction along the first drop path 36. Here, even if the coil spring 37 of the first embodiment moves downward most during the reciprocating movement, the lower end is set to a length separated from the discharge port 34 which is the downstream end of the first drop path 36. ing.
Such a configuration in which the coil spring 37 is reciprocally moved by the crankshaft 38 is conventionally known. For example, the configuration described in the cited document 3 can be applied, and thus detailed description thereof is omitted.
In the first drop path 36 of the first embodiment, the developer flowing in from the relay path 12 is guided by the action of gravity while being in contact with the left inner surface 33a positioned below the relay path 12 in the gravity direction. The fall path 36 is dropped. At this time, the developer attached to the inner surface such as the left inner surface 33 a is broken and dropped by the reciprocating movement of the coil spring 37, and is conveyed in the first dropping path 36.

  In FIG. 6, a second drop path 41 is formed on the right side of the first drop path 36. A second inflow port 42 is formed in the upper part of the second drop path 41. The second inlet 42 is connected to the lower end of the developing ramp 23 of the discharged developer discharge path 24, and the developer that has fallen through the developing ramp 23 flows into the second inlet 42. In the first embodiment, the lower end portion 23a of the developing ramp 23 extends downward in the gravitational direction, and the developer that falls on the developing ramp 23 falls in the gravitational direction and the second inflow port 42. It is configured to be able to flow into. A second drop cylinder 43 formed in a substantially cylindrical shape is formed below the second inlet 42 as an example of a second drop path main body. As an example of the direction in which the developer dropped inside falls toward the discharge port 34, the second dropping cylinder 43 extends in a direction that inclines to the left as it progresses downward in the direction of gravity. Then, the downstream end of the second drop cylinder 43 is connected to the right side of the first drop path 36 from above in the direction of gravity, and the second drop path 41 and the first drop path 36 are Are connected by a connection port 44 as an example of the connection portion.

The second dropping cylinder 43 has a left inner surface 43a and a right inner surface 43b. Of the inner surfaces 43a and 43b, the lower end of the upper left inner surface 43a in the gravitational direction is connected to the right inner surface 33b of the first dropping path 36 at the upper connection position 44a shown in FIG. The lower end of the right inner surface 43b is connected to the right inner surface 33b of the first drop path 36 at the lower connection position 44b shown in FIG.
The second inlet 42 and the second drop cylinder 43 constitute a second drop path 41 of the first embodiment.
In the second drop path 41, the developer that has dropped the discharged developer discharge path 24 and entered the second inflow port 42 falls inside. Then, when the developer that has dropped inside passes through the connection port 44 that is the downstream end of the second drop path 41, the developer falls toward the discharge port 34.
The first fall path 36 and the second fall path 41 constitute the fall path 31 of the first embodiment.

As an example of the space, the dropping path 31 is formed with a through space 46 through which the space from the second inlet 42 to the outlet 34 penetrates along the direction of gravity. That is, in FIG. 6, the second line between the broken line L1 extending in the gravity direction through the lower connection position 44b and the broken line L2 extending in the gravity direction through the left end portion 42a of the second inflow port 42. A through space 46 is formed in which the space from the inlet 42 to the outlet 34 penetrates along the direction of gravity.
In the first dropping path 36 of the first embodiment, the right inner surface 33b of the lower portion in the gravity direction with respect to the lower connection position 44b is inclined to the right side as it proceeds downward in the gravity direction. Yes. That is, the direction in which the dropping path 31 on the downstream side of the connection port 44 extends with respect to the inclination direction of the second dropping path 41 extending in a direction inclined with respect to the gravity direction is reversed across the gravity direction. Is set to the side.
Further, in the dropping path 31, as an example of the extension of the developer dropping direction from the second dropping path 41, the developer from the second dropping path 41 falls in the first dropping path 36. The coil spring 37 is arranged on the extension of the falling direction Y1.

  4 and 6, a horizontal path 51 extending toward the right in the horizontal direction is connected to the downstream end of the drop path 31 as an example of a downstream discharge path. Inside the horizontal path 51, an auger as an example of a conveying member that conveys the developer flowing in from the discharge port 34 as an example of a connecting portion where the falling path 31 and the horizontal path 51 are connected to the right. 52 is arranged. The auger 52 has a rotating shaft 52a extending along the horizontal path 51, and a conveying blade 52b provided in a spiral shape around the rotating shaft 52a. In the horizontal path 51 of the first embodiment, an extended buffer portion 51a is formed upstream of the discharge port 34 in the normal conveying direction of the auger 52, that is, to the left of the discharge port 34. Yes. In the first embodiment, the buffer 51a is formed to correspond to a movement distance per one rotation of the conveying blade 52b of the auger 52, so-called one pitch.

3 and 4, a recovery dropping path 61 through which developer flows and falls is connected to the lower right end of the horizontal path 51. The recovery dropping path 61 of the first embodiment is formed in a conical shape that is inclined to the right as it proceeds downward, and a coil spring 62 as an example of a vibration member of the recovery dropping path is disposed inside. The coil spring 62 is supported by a crankshaft 63 as an example of a rotation shaft of the recovery fall path, and reciprocates in the recovery fall path 61 with the same configuration as the coil spring 37.
3, 4, and 5 </ b> D, the rear end of a connection path 64 that extends forward is connected to the lower end of the recovery drop path 61 as an example of a discharge path. An auger 66 as an example of a transport member that transports the developer in the connection path 64 forward is disposed inside the connection path 64. A collection case 67 that is long in the front-rear direction as an example of a collection container is disposed at the front end of the connection path 64, and the developer conveyed by the auger 66 is discharged. A coil spring 68 extending in the front-rear direction is disposed in the collection case 67 as an example of a conveying member. The coil spring 68 has a free end at the front end and is supported only at the rear end. The coil spring 68 is leveled while transporting the developer contained in the collection case 67.

In FIG. 3, in the discharge path 1 + 2 + 4 for the photosensitive member, a drive gear G1 as an example of a drive transmission member is supported at the rear end of the auger 3 of the relay path 2. A driving force is transmitted to the driving gear G1 from a driving source (not shown). An intermediate gear G2 that meshes with the drive gear G1 is supported as an example of a drive transmission member at the lower left of the drive gear G1. Above the intermediate gear G2, an intermediate gear G3 that meshes with the intermediate gear G2 is supported. The intermediate gear G3 includes a rear large-diameter portion G3a meshing with the intermediate gear G2, and a screw gear-shaped small-diameter portion G3b formed forward and rotating integrally with the large-diameter portion G3a. A driven gear G4 that meshes with the large-diameter portion G3a is supported on the upper right of the intermediate gear G3 as an example of a driven member. The driven gear G4 is supported by the rear end of the auger CL1c of the photoreceptor cleaner CL1, and rotates integrally with the auger CL1c. Further, a screw gear-like driven gear G5 that meshes with the small-diameter portion G3b is supported as an example of a driven member at the lower right of the intermediate gear G3. The driven gear G5 is supported by the upper left end of the auger 6 on the ramp 4 and rotates integrally with the auger 6.
When the driving gear G1 receives driving force and rotates, the augers CL1c, 3 and 6 rotate through the gears G2 to G5, and the developer collected from the photosensitive drum PR is conveyed.

In FIG. 3, in the discharge path 11 + 12 for the intermediate transfer belt, a drive gear G11 as an example of a drive transmission member is supported at the rear end of the auger 13 of the combined flow path 12. The driving gear G11 receives driving force from a driving source (not shown). In the first embodiment, the driving force is transmitted from the same driving source to the driving gear G11 and the belt driving roll Rd via a gear train (not shown).
A driven gear G12 that meshes with the driving gear G11 is supported above the driving gear G11. The driven gear G12 is supported at the rear end of the auger CLc2 of the belt cleaner CL2, and rotates integrally with the auger CL2c.
An intermediate gear G13 that meshes with the drive gear G11 is supported as an example of a drive transmission member at the lower right of the drive gear G11. A crank gear G14 that meshes with the intermediate gear G13 is supported as an example of a drive transmission member at the lower left of the intermediate gear G13. The crank gear G14 is supported at the rear end of the crankshaft 38 and rotates integrally with the crankshaft 38. In the first embodiment, the crankshaft 38 is set to rotate counterclockwise in FIG.

  The crank gear G14 has a front large-diameter portion G14a that meshes with the intermediate gear G13, and a rear small-diameter portion G14b that rotates integrally with the large-diameter portion G14a. An intermediate gear G15 that meshes with the small-diameter portion G14b is supported as an example of a drive transmission member at the lower right of the small-diameter portion G14b. An intermediate gear G16 that meshes with the intermediate gear G15 is supported as an example of a drive transmission member at the lower left of the intermediate gear G15. An intermediate gear G17 that meshes with the intermediate gear G16 is supported as an example of a drive transmission member at the lower right of the intermediate gear G16.

The intermediate gear G17 includes a rear large-diameter portion G17a that meshes with the intermediate gear G16, and a screw gear-shaped small-diameter portion (not shown) that is formed forward and rotates integrally with the large-diameter portion G17a. . A screw gear-shaped intermediate gear G18 that meshes with the small diameter portion of the intermediate gear G17 is supported as an example of a drive transmission member below the small diameter portion of the intermediate gear G17. The intermediate gear G18 is supported by a shaft 71 that extends along the horizontal path 51 and is rotatably supported as an example of a shaft member, and rotates integrally with the shaft 71. An intermediate gear G19 that rotates integrally with the shaft 71 is supported at the left end of the shaft 71 as an example of a drive transmission member. A driven gear G20 that meshes with the intermediate gear G19 is supported in front of the intermediate gear G19 as an example of a driven member. The driven gear G20 is supported at the left end of the auger 52 and rotates integrally with the auger 52.
Therefore, when the drive gear G11 rotates, the augers CL2c, 13, 52 and the coil spring 37 are driven via the gears G12 to G20 and the shaft 71. As a result, the developer is conveyed through the relay path 12, the drop path 31, and the like.

  At the right end of the shaft 71, as an example of a drive transmission member, a bevel tooth-shaped intermediate gear G31 that rotates integrally with the shaft 71 is supported. An intermediate gear G32 that meshes with the intermediate gear G31 is supported behind the intermediate gear G31 as an example of a drive transmission member. The intermediate gear G32 has a bevel-toothed small diameter portion (not shown) that is formed in the front and meshes with the intermediate gear G32, and a rear large diameter portion G32a that rotates integrally with the small diameter portion. An intermediate gear G33 that meshes with the large diameter portion 32a is supported on the upper right of the large diameter portion 32a as an example of a drive transmission member. The intermediate gear G33 has a rear large-diameter portion G33a that meshes with the large-diameter portion G32a, and a rear small-diameter portion G33b that rotates together with the large-diameter portion G33a. On the right side of the small-diameter portion G33b, an intermediate gear G34 that meshes with the small-diameter portion G33b is supported as an example of a drive transmission member. A pulley G35 that meshes with the intermediate gear G34 is supported on the right side of the intermediate gear G34 as an example of a drive transmission member. The pulley G35 includes a front gear portion G35a that meshes with the intermediate gear G34, and a front pulley portion G35b that rotates integrally with the gear portion G35a.

A pulley G36 as an example of a drive transmission member is supported at the lower left of the pulley G35. The pulley G36 is supported at the rear end of the crankshaft 63 of the recovery dropping path 61, and rotates integrally with the crankshaft 63. A pulley G37 as an example of a drive transmission member is supported on the lower right side of the pulley G36 corresponding to the rear of the lower end of the drop recovery path 61. The pulley G37 is supported at the rear end of the auger 66 of the connection path 64, and rotates integrally with the auger 66. Above the pulley G37, a pulley G38 as an example of a transmission assisting member is supported. The pulleys G35b and G36 to G38 support a transmission belt 72 as an example of a drive transmission member, which is an example of a belt-like member.
Therefore, when the shaft 71 rotates, the pulley G35 rotates through the gears G31 to G34. When the pulley G35 is rotated, the pulleys G36 to G38 are rotated via the transmission belt 72, the auger 66 and the coil spring 62 are driven, and the developer is conveyed to the collection case 67.

In FIG. 5D, a gear portion G37a as an example of a drive transmission member is formed at the front portion of the pulley G37, and when the gear portion 37a rotates, a drive provided at the rear portion of the collection case 67. The coil spring 68 supported by the intermediate gear G44 is driven via intermediate gears G41 to G44 as an example of the transmission member.
The members denoted by the reference numerals 1 to 72 and G1 to G44, etc. constitute the waste developer transport device UH of the first embodiment.

(Operation of Example 1)
In the image forming apparatus U of Example 1 having the above-described configuration, when an image forming operation is started, an electrostatic latent image is formed on the surface of the photosensitive drum PR. The developing devices GK to GC of the developing device G develop the electrostatic latent image formed on the surface of the photosensitive drum PR into a toner image Tn. When the photosensitive drum PR rotates and the developed toner image Tn is conveyed to the primary transfer region Q3, the primary transfer roll T1 moves the toner image Tn on the photosensitive drum PR onto the intermediate transfer belt B. Transcript. When the intermediate transfer belt B rotates and the primary-transferred toner image Tn is conveyed to the secondary transfer region Q4, the secondary transfer unit T2 transfers the toner image Tn on the intermediate transfer belt B onto the recording sheet S. Transcript to. Then, the fixing device F fixes the toner image Tn transferred to the recording sheet S, and an image is recorded on the recording sheet S.

At this time, the photoreceptor cleaner CL1 cleans the surface of the photoreceptor drum PR after the toner image Tn is transferred to the surface of the intermediate transfer belt B, and residual toner remaining without being transferred to the intermediate transfer belt B. The developer is collected from the photosensitive drum PR. The developer recovered from the photosensitive drum PR is transported to the waste developer transport device UH, and transported toward the fall path 31 through the recovered developer discharge path 14.
Further, the belt cleaner CL2 cleans the surface of the intermediate transfer belt B after the toner image Tn is transferred to the recording sheet S, and removes residual developer such as residual toner without being transferred to the recording sheet S. Collect from belt B. The developer recovered from the intermediate transfer belt B is transported to a waste developer transport device UH, and transported toward the fall path 31 through the recovered developer discharge path 14.
Further, in each of the developing devices GK to GC of the developing device G, a developer such as consumed toner is replenished, and the developer including a carrier whose chargeability is deteriorated is gradually discharged. The developer discharged from the developing units GK to GC is transported to the waste developer transport device UH, and transported toward the falling path 31 through the discharged developer discharge path 24.

FIG. 7 is a diagram corresponding to FIG. 6 and is an operation explanatory diagram of the first embodiment.
In the drop path 31 of the first embodiment, the developer conveyed through the collected developer discharge path 14 flows from the first inflow port 32, falls through the first drop path 36, and is conveyed to the discharge port 34. The That is, the developer flowing in from the first inflow port 32 falls in the first drop path 36 in the direction of the arrow Y2 in FIG. Then, when the developer that has fallen in the direction of the arrow Y2 reaches the left inner surface 33a disposed below the gravitational direction, the developer is guided to the left inner surface 33a in the direction of the arrow Y3 shown in FIG. 7 along the left inner surface 33a. It falls and is conveyed to the discharge port 34.
On the other hand, the developer conveyed through the discharged developer discharge path 24 falls on the development inclined path 23 and flows into the second drop path 41 from the second inlet 42. The developer flowing in from the second inflow port 42 is guided by the right inner surface 43b arranged below the direction of gravity depending on the flowing direction and position, and falls in the direction of arrow Y4 shown in FIG. 7 along the right inner surface 43b. Or drop in the direction of arrow Y5 shown in FIG. Then, the developer that has passed through the second drop path 41 falls in the first drop path 36 in the direction of the arrow Y1 and is conveyed toward the discharge port 34.

FIG. 8 is an explanatory view of a conventional dropping path, FIG. 8A is an explanatory view of a connecting portion between the dropping path and a downstream conveying path, and FIG. 8B corresponds to a sectional view taken along line VIIIB-VIIIB in FIG. 8C is an explanatory diagram subsequent to FIG. 8B, and FIG. 8D is an explanatory diagram subsequent to FIG. 8C.
In FIG. 8, generally, the developer 03 dropped in the dropping path 01 is collected and conveyed by the auger 04 at the connecting portion between the dropping path 01 and the downstream conveying path 02, that is, at the downstream end of the dropping path 01. 4B to 4D, when the developer 03 is transported in a state where it has accumulated, the developer 03 inside the rotation radius of the transport member 04 is transported downstream, but outside the rotation radius of the transport member 04. As shown in FIG. 8C, the developer 03a may remain attached to the inner surfaces of the transport paths 01 and 02. In this state, when the developer 03 is transported from the dropping path 01, the developer 03 is further deposited and attached to the attached developer 03a, and the developer 03a attached to the inner surface grows. There is. That is, at the downstream end of the falling path 01, the adhered developer 03a grows up and closes the falling path 01, and the developer may be clogged.

Therefore, in the configuration in which the conveying member, the vibrating member, and the like are not arranged in the dropping path, the developer is easily clogged at the downstream end of the dropping path. In particular, when the developer collected from the image carrier is transported through a dropping path, the developer collected from the image carrier is subject to electrical and mechanical loads during development, transfer, and collection. In addition, the fluidity is reduced, and it becomes easy to clog at the downstream end of the dropping path.
In the technique described in the conventional patent document 2, the developer recovered from the image carrier above the drop path on the upstream side in the transport direction is the developer discharged from the developing device, and the image carrier The developer clogged from the upstream part to the downstream part of the dropping path is caused by merging and dropping the developer that is less deteriorated and has high fluidity compared to the developer from Was trying to reduce. However, even if the developer discharged from the developing device and the developer collected from the image carrier are merged and dropped, the developer cannot be completely blocked at the downstream end of the dropping path.

  Here, in the configuration of the conventional Patent Documents 2 and 3, a metal ball is disposed at the discharge port of the drop path, and is brought into contact with a conveying member below the metal ball to vibrate, or a plurality of coil springs are placed in the drop path. It was arranged and conveyed while destroying the adhered developer. However, in the configuration in which the metal balls are arranged, the cross section in the transport direction in the dropping path is reduced. Therefore, when printing a high-density image that consumes a large amount of developer, such as a photographic image, if the amount of collected developer or discharged developer increases, a large amount of developer is conveyed to the falling path, There is a possibility that the developer may adhere to the inner surface of the dropping path and be clogged without passing through to the downstream side of the metal sphere. Further, in the configuration in which the metal ball and the conveying member are in contact with each other or the coil springs are in contact with each other, noise is likely to occur. Furthermore, in the configuration in which a plurality of metal balls and coil springs are arranged, the number of parts increases and the cost is easily increased.

On the other hand, in the dropping path 31 of the first embodiment, the developer recovered from the intermediate transfer belt B or the like and having a high residual toner ratio and deteriorated in fluidity is collapsed by the coil spring 37 while being first broken. Is dropped by its own weight in the dropping path 36 and conveyed to the discharge port 34. On the other hand, the developer discharged from the developing units GK to GC and having a high carrier ratio and high fluidity falls in the second drop path 41 by its own weight and passes through the second drop path 41, and then the coil spring 37. Or the auger 52 does not reach and tends to drop directly toward the discharge port 34 where the developer may be clogged.
Therefore, even if the developer flowing in from the first inflow port 32 adheres to the discharge port 34, the developer flowing in from the second inflow port 42 falls directly on the discharge port 34 and easily gives an impact. It has become. That is, in Example 1, the developer that has flowed in from the second inflow port 42 easily breaks the developer that has adhered to the discharge port 34, and clogging of the developer is less likely to occur.

  In particular, in the first embodiment, the developer that drops and gives an impact to the discharge port 34 is the developer discharged from the developing devices GK to GC, and is different from the developer collected from the intermediate transfer belt B or the like. High fluidity and difficult to clog. In addition, the developer discharged from the developing units GK to GC includes a carrier, and is composed of a substance having a larger particle diameter or mass than the developer flowing in from the first inflow port 32. Therefore, the impact at the time of collision is likely to increase. Therefore, compared with the case where the collected developer is collided or the collected developer is collided with the developer discharged from the developing devices GK to GC, in the first embodiment, the discharge port The developer adhering to 34 is easily broken.

Further, in the first embodiment, no member such as a metal ball is disposed in the discharge port 34 that may be clogged with the developer. Therefore, even if a high density image is printed and the amount of developer conveyed in the dropping path 31 increases, the cross section in the conveyance direction at the discharge port 34 is difficult to narrow, and the developer is not easily clogged. Further, when a high density image is printed, even if the developer collected from the intermediate transfer belt B or the like and flowing in from the first inflow port 32 increases, it is discharged from the developing devices GK to GC and is supplied to the second flow. The amount of developer flowing in from the inlet 42 is also increasing, and the amount of developer that falls from the second inflow port 42 to the discharge port 34 and collides with the amount of developer that can adhere to the discharge port 34 is ensured. It is easy to ensure and the impact force is also easily secured.
Therefore, in Example 1, it is difficult for the developer to be clogged without arranging a metal ball, a plurality of coil springs, and the like, and it becomes easier to reduce clogging of the developer with a simple configuration compared to the conventional configuration. Yes. Moreover, in Example 1, the metal ball | bowl, several coil springs, etc. are not arrange | positioned, but compared with the conventional structure, it is easy to reduce cost and it is hard to produce noise.

  Further, in the first embodiment, the developer discharged from the developing units GK to GC falls on the developing slope 23, flows in from the second inlet 42, and falls on the dropping path 31. Therefore, the developer discharged from the developing devices GK to GC has an initial speed in the downward direction in the direction of gravity according to the configuration of the developing ramp 23 when passing through the second inflow port 42. The drop speed when reaching the outlet 34 tends to increase. In particular, in the dropping path 31 of the first embodiment, the through space 46 is formed, and the developer that has entered the through space 46 from the developing inclined path 23 from above in the direction of gravity does not contact the inner surface of the falling path 31. It becomes easy to fall to the discharge port 34, and it is less likely that the fall speed is lowered by contacting the inner surface of the second fall path 41 during the fall. Therefore, compared to the case where the through space 46 is not formed, the falling speed of the developer when reaching the discharge port 34 is likely to increase, the impact at the discharge port 34 is likely to increase, and the ability to break the developer is obtained. It has improved.

Furthermore, in Example 1, the extending direction of the dropping path 31 on the downstream side of the connection port 44 is set on the opposite side with respect to the inclination direction of the second dropping path 41 with respect to the gravitational direction. In addition, the developer that has fallen on the second drop path 41 is likely to fall away from the right inner surface 33b of the first drop path 36, and is difficult to contact the right inner face 33b. Therefore, when entering the first fall path 36 from the second fall path 41, it is easy to fall freely without contacting the first fall path 36, and the downstream side of the connection port 44 is an extension of the second fall path 41. Compared to the case where the developer drops while contacting the inner surface of the second drop path 41, the drop speed is less likely to be reduced.
Therefore, in the first embodiment, the falling speed of the developer flowing in from the second inflow port 42 is difficult to be reduced, and the impact when reaching the discharge port 34 is increased, so that the adhering developer is more It is easy to collapse.

  In the drop path 31 of the first embodiment, a coil spring 37 is disposed on the extension of the drop direction Y1 in which the developer from the second drop path 41 falls in the first drop path 36. Therefore, the developer falling on the second dropping path 41 comes into contact with the coil spring 37, and the coil spring 37 is easily vibrated irregularly. Therefore, compared with the case where the crankshaft 38 rotates and the coil spring 37 merely reciprocates, the moving range of the coil spring 37 is easily expanded, and the developer attached to the coil spring 37 is easily removed.

In the first embodiment, when the intermediate transfer belt B is driven, the intermediate transfer belt B is temporarily reversely rotated at a preset time, so that the cleaning blade CL2b of the belt cleaner CL2 is interposed between the intermediate transfer belt B. Developers such as jammed paper dust and residual toner are removed.
In the waste developer transport device UH of the first embodiment, the drive roller Rd and the drive source of the intermediate transfer belt B are shared, and the waste developer transport device UH is associated with the reverse rotation of the intermediate transfer belt B. The gears G11 to G44 and the like rotate reversely, and the auger 52 of the horizontal path 51 rotates reversely. When the auger 52 rotates in the reverse direction, the developer in the horizontal path 51 is transported to the side opposite to the normal transport direction, that is, the upstream side in the normal transport direction. Here, the horizontal path 51 of the first embodiment is provided with a buffer portion 51a on the upstream side in the normal transport direction, and a space for transporting the developer is provided. Therefore, in the first embodiment, the developer can be accommodated at the upstream end of the horizontal path 51 even when the auger 52 rotates in reverse as compared with the case where the buffer 51a is not provided in the horizontal path 51. From 51, the developer is difficult to leak or break.

Next, a second embodiment of the present invention will be described. In the description of the second embodiment, components corresponding to the components of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. To do.
This embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.
FIG. 9 is an explanatory diagram of a falling path of the second embodiment and corresponds to FIG. 6 of the first embodiment.
The fall path 31 'of the second embodiment has a second fall path 41' formed along the direction of gravity in place of the second fall path 41 of the first embodiment. That is, the second drop path 41 ′ of the second embodiment is formed downward from the second inflow port 42 ′ in the direction of gravity, and the lower end of the second drop path 41 ′ is connected to the discharge port 34. It is connected to the first drop path 36 above in the direction of gravity. Accordingly, in the second embodiment, the through space 46 ′ is constituted by the second drop path 41 ′.

(Operation of Example 2)
In the image forming apparatus U according to the second embodiment having the above-described configuration, the developer collected from the intermediate transfer belt B or the like passes through the first drop path 36 while the first drop path 36 is broken by the coil spring 37. It is dropped by its own weight and conveyed to the discharge port 34. On the other hand, the developer discharged from the developing units GK to GC falls easily in the second drop path 41 ′ by its own weight and easily falls directly toward the discharge port 34.
Therefore, even in Example 2, the developer in the discharge port 34 is easily broken without arranging a metal ball or a plurality of coil springs, and the clogging of the developer is reduced with a simple configuration compared to the conventional configuration. It is easy to do. In particular, in the second embodiment, the developer that has entered the second drop path 41 ′ is easy to fall down in the direction of gravity without being guided by the inner surface, and is unlikely to be decelerated due to contact with the inner surface. The drop speed when reaching 34 is likely to increase, and the developer attached to the discharge port 34 is more likely to break down.

(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 (H011) of the present invention are exemplified below.
(H01) In each of the above-described embodiments, a configuration using a copying machine is illustrated as an example of the image forming apparatus U. However, the present invention is not limited to this. is there.
(H02) In each of the above embodiments, the configuration of the rotary type developing device G has been exemplified. However, the present invention is not limited to this. In addition to the developing devices GK to GC for each color, a photosensitive drum PR is provided for each color. It is possible to apply the configuration of the present invention to a so-called tandem image forming apparatus. Further, the present invention is not limited to a multicolor image forming apparatus, and the configuration of the present invention can be applied to a single color image forming apparatus.

(H03) In each of the above embodiments, the toner image Tn is primarily transferred from the photosensitive drum PR, which is an example of the first image carrier, to the intermediate transfer belt B, which is an example of the second image carrier. The configuration in which the toner image Tn is secondarily transferred from the belt B to the recording sheet S and the developer is recovered from the photosensitive drum PR and the intermediate transfer belt B is illustrated, but the present invention is not limited to this. For example, by applying the configuration of the present invention to a configuration in which the toner image Tn is directly transferred from the photosensitive drum PR to the recording sheet S, the developer discharged from the developing device is applied to the developer collected from the photosensitive drum PR. It is possible to make a configuration in which the battery is dropped and collided. Further, the configuration of the present invention is applied to a configuration in which the toner image Tn is transferred from the intermediate transfer belt B to the third image holding member and the toner image Tn is finally transferred from the third holding member to the recording sheet S. Thus, a configuration in which the developer discharged from the developing device is dropped and collided with the developer collected from the third image holding member is possible.

(H04) In each of the above embodiments, the first dropping path 36 is exemplified by a configuration in which the developer recovered from the photosensitive drum PR and the developer recovered from the intermediate transfer belt B are conveyed. However, the present invention is not limited to this, and a configuration in which only the developer recovered from the intermediate transfer belt B, which is more deteriorated and clogged, is transported as compared with the developer recovered from the photosensitive drum PR. Therefore, for example, only the discharge path 11 + 12 for the intermediate transfer belt is connected to the first drop path 36, and the discharge path 1 + 2 + 4 for the photoconductor is connected to the upstream end of the horizontal path 51. In the configuration 31, only the developer recovered from the intermediate transfer belt B can be broken by the developer discharged from the developing units GK to GC. Further, it is desirable that the developer collected from the intermediate transfer belt B is conveyed to the dropping path, but it is also possible to adopt a configuration in which only the developer collected from the photosensitive drum PR is conveyed to the first dropping path 36. is there.
(H05) In each of the above-described embodiments, a configuration in which the developer collected via the photoreceptor cleaner CL1 and the belt cleaner CL2 and the developer discharged from the developing devices GK to GC is conveyed to the dropping path. However, it is not limited to this. For example, a cleaning device is provided in the secondary transfer roll T2b of the secondary transfer device T2, and the developer collected through the cleaning device of the secondary transfer roll T2b and the other developer are conveyed to the dropping path. A configuration in which the developer discharged from the developing devices GK to GC is dropped and collided with the developer collected through an arbitrary member such as a configuration is possible. That is, it is possible to adopt a configuration in which the developer discharged from the developing devices GK to GC is dropped and collided with the developer collected from an arbitrary image carrier.

(H06) In the first embodiment, it is desirable that the through space 46 is provided, but a configuration in which the through space 46 is omitted is also possible.
(H07) In each of the above embodiments, it is desirable that the drop spring 31 is provided with a coil spring 37 as an example of a vibration member. However, the coil spring 37 can be omitted from the drop path 31.
(H08) In each of the above embodiments, it is desirable that the coil spring 37 is disposed on the extension of the dropping direction Y1 in which the developer from the second dropping path 41 falls in the first dropping path 36. A configuration in which the coil spring 37 is not disposed on the extension in the dropping direction Y1 is also possible.
(H09) In the first embodiment, the extending direction of the dropping path 31 on the downstream side of the connection port 44 with respect to the inclination direction of the second falling path 41 is set on the opposite side across the gravitational direction. It is desirable that the direction in which the dropping path 31 extends is not set on the opposite side across the direction of gravity.

(H010) In each of the above-described embodiments, the configuration of the discharged developer discharge path 24 connected to the second inlet 42 of the drop path 31 is not limited to the configuration of the development inclined path 23, and the developing device G or the drop Depending on the arrangement position of the path 31, any configuration is possible. For example, the discharged developer may fall freely from the developing device G and flow into the second inflow port 42, or from a discharge path that is gently inclined as compared to the inclination direction of the second drop path 41. A configuration of a discharge path that flows into the second inlet 42 or a configuration of a discharge path that is horizontally connected to the second drop path 41 and is transported in the horizontal direction and flows into the second inlet 42 is also possible. It is.
(H011) In the above embodiment, the horizontal path 51 is desirably provided with a buffer 51a, but a configuration in which the buffer 51a is omitted is also possible.

1 + 2 + 4, 11 + 12, 14 ... discharge path for the image carrier,
24: Discharge path for developing device,
31. Fall road,
34... A connecting portion where the falling path and the downstream discharge path are connected;
36. First fall path,
37 ... vibrating member,
41 ... second fall path,
42 ... Inlet,
44... Connection portion between the second fall path and the first fall path,
51 ... downstream discharge path,
52... Conveying member on the downstream side,
GK, GY, GM, GC ... developer,
B: Medium, image carrier,
F: Fixing device,
PR: Image carrier,
S ... medium
T1, T2 ... transfer device,
Tn: Visible image,
U: Image forming apparatus,
UH ... Developer transport device,
Y1... The direction in which the developer drops from the second drop path.

Claims (3)

A discharge path for the developer to which the developer including the toner discharged from the developer for developing the latent image on the surface of the image carrier and the carrier is conveyed;
A discharge path for the image carrier through which the developer recovered from the surface of the image carrier after the visible image is transferred to the medium;
A first dropping path to which the developer discharged from the image holding body discharge path is connected and dropped is connected to the image holding body discharge path, and the developer discharge path is connected to the image holding body. A drop path having a second drop path through which the developer discharged from the developer discharge path flows and falls;
A downstream discharge path connected to the downstream end of the drop path, to which the developer passing through the drop path is conveyed;
A direction in which the downstream end is connected to the first drop path from above in the direction of gravity, and the developer that has dropped inside falls toward the connection portion where the drop path and the downstream discharge path are connected Said second dropway extending to
An inflow port through which the developer discharged from the discharge path for the developing device flows; from the inflow port;
The fall path having a space penetrating along the direction of gravity between the connection portions;
A downstream side that is disposed in the downstream discharge path and conveys the developer that has passed through the fall path.
A conveying member;
The lower end is disposed in the first drop path, and the lower end thereof is connected to the downstream portion from the downstream conveying member.
In a state of being separated, reciprocatingly vibrates in the direction along the first fall path inside the first fall path.
A vibrating member;
The vibrating member disposed on an extension of the developer dropping direction from the second drop path;
A developer conveying device comprising: The falling path extends downstream from the connecting portion between the second falling path and the first falling path with respect to the inclination direction of the second falling path extending in a direction inclined with respect to the direction of gravity. The falling path whose direction is set on the opposite side across the direction of gravity; and
The developer conveying device according to claim 1, comprising: A developer for developing the latent image into a visible image;
An image carrier for holding a visible image on the surface;
A transfer device for transferring a visible image of the image carrier to a medium;
A fixing device for fixing the visible image transferred to the medium to the medium;
A developer discharge path for transporting a developer containing toner and a carrier discharged from the developer; and an image carrier discharge path for transporting the developer recovered from the surface of the image holder. ,
The developer conveying device according to claim 1 or 2 ,
An image forming apparatus comprising: