JP5162951B2 - Developer transport device and image forming apparatus - Google Patents

Description

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

Conventionally, in an image forming apparatus such as an electrophotographic copying machine or printer, a latent image formed on the surface of a photosensitive member is developed by a developing device, and the developed visible image is transferred and fixed on a medium to form an image. It is carried out. In such an image forming apparatus, the developing device includes a developer conveying device.
A configuration in which a new developer is supplied from a replaceable developer supply container, a so-called toner cartridge, is widely used.
As techniques for replenishing a developer using the developer conveying device, techniques described in Patent Documents 1 and 2 below are known.

In Patent Document 1 (Japanese Patent Laid-Open No. 4-139469), toner in a cartridge (1021) is supplied to a reserve tank (1022) below, and is circulated in the reserve tank (1022). Describes a toner supply device (1020) supplied to a developing means (53) from a supply port (1048).
In Patent Document 2 (Japanese Patent Laid-Open No. 11-84846), the toner hopper (43) arranged in the information of the developing roller (40) is moved to the developing chamber (44) by the toner supply roller (50, 51). A technique is described in which the developer is dropped and conveyed, and the toner solidified in the toner hopper (43) is broken by a sheet (55) arranged along the wall surface of the toner hopper (43).

As described in Patent Documents 1 and 2, in the conventional developer replenishing device, forcible development is performed at the connecting portion between the cartridge and the developer replenishing device and at the connecting portion between the developer conveying device and the developing device. A member for conveying the developer is not provided, and the developer is conveyed by the supply pressure of the developer being conveyed. In the conventional configuration, because the developer supply amount per unit time may not be stable due to clogging of the developer at the connection part, supply is possible even though the image forming apparatus is limited in size and freedom of design. The side was arranged upward and the supplied side was arranged below, and it was conveyed by dropping due to gravity.

JP-A-4-139469 (4th page, upper left column, 8th line to 6th page, lower left column, 4th line, FIG. 3, FIG. 4, FIG. 6) Japanese Patent Laid-Open No. 11-84846 (“0049” to “0054”, FIGS. 2 and 4)

In view of the above-described circumstances, an object of the present invention is to reduce the clogging of the developer at the opening of the developer conveying device.

In order to solve the technical problem, the developer conveying device according to claim 1 ,
A developer transport path having an inlet through which the developer flows;
A conveyance member having a rotation shaft and a conveyance blade supported by the rotation shaft, and disposed in the developer conveyance path to convey the developer;
A clogging prevention member that is supported by the rotation shaft and has a flexibility that allows a tip portion to enter and retreat into the inflow port as the rotation shaft rotates.
With
The width of the inflow port in the developer conveyance direction is V, the pitch that is the interval between adjacent blades in the axial direction of the conveyance blade is A, and the center of the rotation shaft to the inner wall of the developer conveyance path of the inflow port portion. R is the distance, L is the mounting width of the clogging prevention member to the rotating shaft, r1 is the free length of the clogging prevention member upstream in the developer conveyance direction, and the clogging prevention member is downstream in the developer conveyance direction. When the free length is r2, the inclination angle of the clogging prevention member with respect to the rotation axis is α, and the inclination angle of the conveying blade with respect to the rotation axis is θ,
V>A> L,
α = θ,
r2 ≧ r1,
R <r1 × sin α,
V ≧ L + r2 × cos α,
It is characterized by satisfying.

In order to solve the technical problem, the developer conveying device of the invention according to claim 2 ,
A developer transport path having an inlet through which the developer flows;
A conveyance member having a rotation shaft and a conveyance blade supported by the rotation shaft, and disposed in the developer conveyance path to convey the developer;
A clogging prevention member that is supported by the rotation shaft and has a flexibility that allows a tip portion to enter and retreat into the inflow port as the rotation shaft rotates.
With
The width of the inflow port in the developer conveyance direction is V, the pitch that is the interval between adjacent blades in the axial direction of the conveyance blade is A, and the center of the rotation shaft to the inner wall of the developer conveyance path of the inflow port portion. R is the distance, L is the mounting width of the clogging prevention member to the rotating shaft, r1 is the free length of the clogging prevention member upstream in the developer conveyance direction, and the clogging prevention member is downstream in the developer conveyance direction. When the free length is r2, the inclination angle of the clogging prevention member with respect to the rotation axis is α, and the inclination angle of the conveying blade with respect to the rotation axis is θ,
V>A> L,
α = θ,
r2 <r1,
R <r2 × sin α,
V ≧ L + r2 × cos α,
It is characterized by satisfying.

In order to solve the technical problem, the developer conveying device of the invention according to claim 3 ,
A developer transport path having an inlet through which the developer flows;
A conveyance member having a rotation shaft and a conveyance blade supported by the rotation shaft, and disposed in the developer conveyance path to convey the developer;
A clogging prevention member that is supported by the rotation shaft and has a flexibility that allows a tip portion to enter and retreat into the inflow port as the rotation shaft rotates.
With
The width of the inflow port in the developer conveyance direction is V, the pitch that is the interval between adjacent blades in the axial direction of the conveyance blade is A, and the center of the rotation shaft to the inner wall of the developer conveyance path of the inflow port portion. R is the distance, L is the mounting width of the clogging prevention member to the rotating shaft, r1 is the free length of the clogging prevention member upstream in the developer conveyance direction, and the clogging prevention member is downstream in the developer conveyance direction. The free length is r2, the inclination angle of the clogging prevention member with respect to the rotation axis is α, the inclination angle of the conveying blade with respect to the rotation axis is θ, and the clogging prevention member at a position where the clogging prevention member is supported by the rotation axis. When the distance between the conveying blade adjacent to the downstream side of the clogging and the downstream end in the axial direction of the clogging prevention member is S2,
V>A> L,
α ≦ θ,
S2 ≧ r2 × sin (θ−α) / sinθ,
V ≧ L + S2,
It is characterized by satisfying.

In order to solve the technical problem, the developer conveying device of the invention according to claim 4 ,
A developer transport path having an inlet through which the developer flows;
A conveyance member having a rotation shaft and a conveyance blade supported by the rotation shaft, and disposed in the developer conveyance path to convey the developer;
A clogging prevention member that is supported by the rotation shaft and has a flexibility that allows a tip portion to enter and retreat into the inflow port as the rotation shaft rotates.
With
The width of the inflow port in the developer conveyance direction is V, the pitch that is the interval between adjacent blades in the axial direction of the conveyance blade is A, and the center of the rotation shaft to the inner wall of the developer conveyance path of the inflow port portion. R is the distance, L is the mounting width of the clogging prevention member to the rotating shaft, r1 is the free length of the clogging prevention member upstream in the developer conveyance direction, and the clogging prevention member is downstream in the developer conveyance direction. The free length is r2, the inclination angle of the clogging prevention member with respect to the rotation axis is α, the inclination angle of the conveying blade with respect to the rotation axis is θ, and the clogging prevention member at a position where the clogging prevention member is supported by the rotation axis. When the distance between the conveying blade adjacent to the upstream side of the clogging and the axial upstream end of the clogging prevention member is S1,
V>A> L,
α> θ,
S1 ≧ r1 × sin (α−θ) / sinθ,
V ≧ L + S1,
It is characterized by satisfying.

In order to solve the technical problem, an image forming apparatus according to claim 5 is provided.
An image carrier,
A developing device for developing the latent image on the surface of the image carrier into a visible image;
The developer conveying device according to any one of claims 1 to 4 , wherein a new developer is conveyed to the developing device;
A transfer device for transferring a visible image developed by the developing device to a medium;
A fixing device for fixing the visible image transferred to the medium;
It is provided with.

According to the invention described in 請 Motomeko 1, it is possible to reduce clogging of the developer in the inlet, the supply amount of the developer can be stabilized. Further, it is possible to reliably prevent clogging at the inlet while preventing the clogging preventing member from being damaged.
According to the second aspect of the present invention, the clogging of the developer at the inflow port can be reduced, and the supply amount of the developer can be stabilized. Further, it is possible to reliably prevent clogging at the inlet while preventing the clogging preventing member from being damaged.
According to the third aspect of the present invention, the clogging of the developer at the inlet can be reduced, and the supply amount of the developer can be stabilized. Further, it is possible to reliably prevent clogging at the inlet while preventing the clogging preventing member from being damaged.
According to the fourth aspect of the present invention, the clogging of the developer at the inflow port can be reduced, and the supply amount of the developer can be stabilized. Further, it is possible to reliably prevent clogging at the inlet while preventing the clogging preventing member from being damaged.
According to the fifth aspect of the present invention, development can be performed with a stably supplied developer, and image quality deterioration can be reduced.

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 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.

1 is a perspective explanatory view of an image forming apparatus according to a first embodiment of the present invention.
FIG. 2 is an overall explanatory view of the image forming apparatus according to the first embodiment of the present invention.
FIG. 3 is an explanatory perspective view of the image forming apparatus according to the first exemplary embodiment of the present invention with the side cover opened.
1 to 3, a printer U as an example of the image forming apparatus according to the first embodiment of the present invention has a paper feed container TR1 in which a recording medium S as an example of a medium on which an image is recorded is accommodated in a lower portion. A paper discharge section TRh is provided on the upper surface. An operation unit UI is provided at the top of the printer U.
The printer U according to the first exemplary embodiment includes an image forming apparatus main body U1, a front cover U2 as an example of an openable opening / closing unit provided on the front side of the image forming apparatus main body U1, and the image forming apparatus U1.
And a side cover U3 as an example of an openable / closable opening / closing portion provided on the side surface. The front cover U2 is used for supplying a developer, replacing a failed member, or a recording medium S that is jammed.
The side cover U3 is opened when the inside of the image forming apparatus main body U1 is opened to remove the toner, and the side cover U3 is opened when the developer supply container, so-called toner cartridge is replaced.
In FIG. 3, when the side cover U3 of the printer U is moved to the open position, the printer U
Toner cartridges TCy, TCm as an example of a developer container
, TCc, and TCk can be handled.

2, the printer U includes a control unit C that performs various controls of the printer U, an image processing unit IPS that is controlled by the control unit C, an image writing device driving circuit DL, a power supply device E, and the like. ing. The power supply device E includes charging rollers CRy to CRk as an example of a charger to be described later, a developing roller as an example of a developer holder, and a transfer roller T1y to T as an example of a transfer device.
A voltage is applied to 1k or the like.

The image processing unit GS converts print information input from an external image information transmission device or the like into latent images corresponding to four color images of K (black), Y (yellow), M (magenta), and C (cyan). The image information is converted into image information for image formation and output to the image writing device driving circuit DL at a predetermined timing. The image writing device driving circuit DL sends a driving signal to the latent image writing device ROS according to the input image information of each color.
Output to. The latent image writing device ROS emits laser beams Ly, Lm, Lc, and Lk as an example of image writing light for image writing of each color in accordance with a drive signal.

In FIG. 2, Y (yellow), M (on the right side (+ Y direction) of the latent image writing device ROS.
Visible image forming apparatuses UY, UM, UC, and UK that form toner images as examples of visible images of respective colors of magenta), C (cyan), and K (black) are arranged.
The K (black) visible image forming apparatus UK has a photoconductor Pk as an example of a rotating image carrier. Around the photosensitive member Pk, a charging roll CRk as an example of a charger, a developing device Gk for developing the electrostatic latent image on the surface of the photosensitive member into a visible image, and a developer remaining on the surface of the photosensitive member Pk are removed. A photoconductor cleaner CLk as an example of an image carrier cleaner is disposed.

The surface of the photoreceptor Pk is uniformly charged by the charging roll CRk in the charging area Q1k facing the charging roll CRk, and then a latent image is written by the laser beam Lk in the latent image forming area. The written electrostatic latent image is visualized in the developing area facing the developing device Gk.
The black visible image forming device UK according to the first exemplary embodiment includes an exchangeable image carrier cartridge in which the photoconductor Pk, the charger CRk, and the photoconductor cleaner CLk are integrally formed and exchangeable, and the developing device Gk. And a possible developing cartridge.
The visible image forming apparatuses UY, UM, and UC of other colors are also composed of an image carrier cartridge and a developing cartridge that can be attached to and detached from the image forming apparatus main body U1 in the same manner as the black visible image forming apparatus UK. ing. In the first embodiment, the four visible image forming devices UY to UK are supported by a detachable frame Ut, a so-called exchange frame Ut.
Y to UK are configured to be interchangeable with the image forming apparatus main body U1.

In FIG. 2, a belt module BM as an example of a recording medium transport device supported by the opening / closing portion U2 is disposed in front of the photoconductors Py to Pk (+ X direction). The belt module BM includes a medium conveying belt B as an example of a recording medium holding and conveying member, a belt driving roll Rd as an example of a driving member that supports the medium conveying belt B, and a driven roll Rj as an example of a driven member. Belt support roll (Rd +) as an example of a holding and conveying member support system
Rj), and a transfer roll T as an example of a transfer device disposed to face each of the photoconductors Py to Pk
1y, T1m, T1c, T1k, and belt cleaner C as an example of a holding and conveying member cleaner
Lb, and a medium adsorbing roll Rk as an example of a recording medium adsorbing member that is disposed to face the driven roll Rj and adsorbs the recording medium S to the medium conveying belt B. The medium transport belt B is rotatably supported by the belt support roll (Rd + Rj).
The image density sensor SN1 is for detecting the density of a density detection image formed by an image density adjusting means (not shown) of the control unit C, that is, a so-called patch image, at a predetermined time. The adjusting means adjusts the voltage applied to the chargers CRy to CRk, the developing devices Gy to Gk and the transfer rolls T1y to T1k based on the image density detected by the image density detecting member, and the latent image writing light Ly to By adjusting the intensity of Lk, image density adjustment and correction, so-called process control is performed.

The recording medium S in the paper supply container TR1 disposed below the medium conveyance belt B is taken out by the paper supply member Rp and conveyed to the recording medium conveyance path SH.
The recording medium S in the recording medium conveyance path SH is conveyed by a medium conveyance roll Ra as an example of a recording medium conveyance member, and is sent to a registration roll Rr as an example of a paper feed timing adjustment member. The registration roll Rr transports the recording medium S to a recording medium suction position Q6 that is a region where the driven roll Rj and the medium suction roll Rk face each other at a predetermined timing. The recording medium S conveyed to the recording medium adsorption position Q6 is electrostatically adsorbed to the medium conveyance belt B.

The recording medium S adsorbed on the medium conveying belt B sequentially passes through the transfer areas Q3y, Q3m, Q3c, and Q3k that are in contact with the photoreceptors Py to Pk.
The transfer rolls T1y, T1m, T1c, and T1k disposed on the back side of the medium conveying belt B in the transfer regions Q3y, Q3m, Q3c, and Q3k include a power supply circuit E controlled by the control unit C.
A transfer voltage having a polarity opposite to the charging polarity of the toner is applied at a predetermined timing.
In the case of a multicolor image, the toner images on the respective photoreceptors Py to Pk are transferred to the transfer rolls T1y and T1m.
, T1c, and T1k, the image is transferred onto the recording medium S on the medium conveying belt B in an overlapping manner. In the case of a monochromatic image, so-called monochrome image, only a K (black) toner image is formed on the photoreceptor Pk, and only this K (black) toner image is transferred to the recording medium S by the transfer device T1k. .
The photoreceptors Py to Pk after the toner image transfer are cleaned by the toner remaining on the surface being collected by the photoreceptor cleaners CLy to CLk, and charged again by the charging rolls CRy to CRk.

The recording medium S to which the toner image has been transferred is in contact with a heating roll Fh as an example of a heating fixing member of a fixing device F as an example of a fixing device and a pressure roll Fp as an example of a pressure fixing member. Fixing is performed in the fixing region Q5 formed in this manner. The recording medium S on which the image is fixed is discharged from a discharge roller Rh as an example of a medium discharge member to the medium discharge unit TRh.
The medium conveying belt B after the recording medium S is separated is cleaned by the belt cleaner CLb.

(Description of developer transport device)
FIG. 4 is an explanatory view showing a state in which a toner cartridge as an example of a developer container is attached and detached.
FIG. 5 is an explanatory diagram of the developer conveying device according to the first exemplary embodiment of the present invention, FIG. 5A is an explanatory diagram viewed from an oblique rear side, and FIG. 5B is a diagram viewed from the direction of arrow VB in FIG.
In the following description, since the members provided for each of the colors Y, M, C, and K are configured in the same manner, the subscripts y, m, c, and k are attached to the reference numerals in the drawings. In the description and specification, subscripts are omitted for easy understanding.
4 and 5, the developer conveying device 1 is fixedly supported inside the right side of the image forming apparatus main body U1. The developer conveying device 1 has a frame 2, and four cartridge mounting portions on which Y, M, C, and K toner cartridges TCy, TCm, TCc, and TCk are mounted in order from the bottom. 3 is formed.
3 to 5, the cartridge mounting portion 3 has cartridge housing containers 4 that can accommodate toner cartridges TCy, TCm, TCc, and TCk, respectively. Color and M colors are not shown), but are supported rotatably around the rear end.

In FIG. 5, a toner cartridge TCy is disposed at the rear end of each cartridge mounting portion 3.
, TCm, TCc, and TCk are formed with an inlet 6 (only the Y inlet is shown in FIG. 5A). A shutter member 7 (see FIG. 5A) as an example of an inlet closing member is disposed at the inlet 6 of each cartridge mounting portion 3. The shutter member 7 has an open position where the inlet 6 shown in the Y-color shutter member 7 of FIG. 5A is opened, and FIG.
The inflow port shown in the M-color shutter member 7 is supported so as to be movable between a closed position and a closed position.
5A and 5B, the frame 2 is formed with a main body-side conveyance path forming recess 8 that is recessed outwardly extending forward from the inflow port 6. A conveyance path forming member 9 (only C color and K color are shown in FIG. 5B) is attached to the inner surface of the frame 2 corresponding to each main body side conveyance path forming recess 8. A developer transport path 11 is constituted by an internal cylindrical space surrounded by the main body side transport path forming recess 8 and the transport path forming member 9. In FIG. 6, the developer transport path 11 extends from the position of the inlet 6 to the developing devices Gy to Gk. The developer transport path 11 of the first embodiment is not linear, but an inflow side horizontal transport section 11a extending in the horizontal direction from the inflow port 6;
Inclined transport unit 11b tilted obliquely upward from inflow side horizontal transport unit 11a, and tilted transport unit 11b
Is formed in a curved shape having a development-side horizontal conveying portion 11d extending in the horizontal direction from the developing device Gy to Gk.

FIG. 6 is an explanatory diagram of the relationship between the developer conveying device and the developing device according to the first embodiment of the present invention.
5B and 6, on the front end side of the transport path forming member 9, a development side horizontal transport section 11d is provided.
A developing device connecting portion 9a is formed, and an outlet shutter 12 as an example of an outlet closing member is attached to the developing device connecting portion 9a. The outlet shutter 12
Is always urged to the front closed position by a spring 13 as an example of an urging member.
The outlet 11f of the developer conveyance path 11 shown in FIG. Accordingly, when the front cover U2 is opened and the developing devices Gy to Gk are removed, the outlet shutter 12 is moved to the closed position by the spring 13 to prevent developer leakage. On the other hand, the developing device Gy
When Gk is attached, the outlet shutter 12 is moved by being pushed by the connected portion 16 (see FIG. 6) of the developing devices Gy to Gk, and the developing device connecting portion 9a is fitted into the connected portion 16. ,
Developer can be supplied to the developing devices Gy to Gk from the outlet 11f.

FIG. 7 is an enlarged explanatory view of a main part of the inlet portion of the developer conveying device according to the first embodiment of the present invention.
FIG. 8 is an explanatory diagram of the developer conveying member according to the first embodiment of the present invention.
5B, FIG. 6 and FIG. 7, a curved developer transport path 1 is provided in the developer transport path 11.
1, the developer conveying member 17 is rotatably supported. 5 to 8, the developer conveying member 17 has a rotating shaft 17a and a helical conveying blade 17b formed on the outer periphery of the rotating shaft 17a. The developer conveying member 17 according to the first exemplary embodiment is made of a flexible resin material, and conveys toner as an example of a developer while being curved into a shape along the developer conveying path 11 as it rotates. To do. In FIG. 7, a large diameter portion 17d having a diameter larger than that of the rotating shaft 17a is formed at a position corresponding to the inlet 6 of the developer conveying member 17.
A clogging prevention member mounting portion 17e is formed in the large diameter portion 17d. In FIG. 5B,
A replenishment motor 19 for each color as an example of a replenishment drive system is supported at the rear end of the frame 2. In FIG. 6, the drive gear 20 supported by the drive shaft 19 a extending from the replenishing motor 19 transmits the drive to the gear 17 g supported at the rear end of the developer transport member 17, so that the developer transport is performed. The member 17 is driven to convey the toner.

FIG. 9 is an explanatory diagram of the length and positional relationship between the developer conveying member and the clogging preventing member according to the first embodiment of the present invention. FIG. 9 is a view from a viewpoint rotated by 180 ° around the axis with respect to the viewpoint of FIG.
7 and 9, one end portion of the clogging prevention member 21 is fixedly supported on the clogging prevention member mounting portion 17e of the developer conveying member 17. The clogging prevention member 21 of the first embodiment is formed in a thin film shape having flexibility, a so-called film shape, and can be made of a resin such as PET (polyethylene terephthalate). In FIG. 9, the developer transport member 17 transports the developer in the developer transport direction Ya.

In FIG. 9, the width of the inlet 6 in the developer conveying direction is V, the pitch that is the distance between the blades adjacent in the axial direction of the conveying blade 17b is A, and the developer conveying path of the inlet portion from the center of the rotating shaft 17a. 11 is the distance to the inner wall R, the mounting width of the clogging prevention member 21 to the rotating shaft 17a is L, the free length of the clogging prevention member 21 on the upstream side in the developer conveyance direction is r1, and the clogging prevention on the downstream side in the developer conveyance direction. When the free length of the member 21 is r2, the inclination angle of the clogging prevention member 21 with respect to the rotating shaft 17a is α, and the inclination angle of the conveying blade with respect to the rotating shaft 17a is θ, the developer conveying member 17 of Example 1 or The size and angle of the clogging prevention member 21 and the inlet 6 are expressed by the following formulas (1) to (
It is set so as to satisfy the relationship 5).
V>A> L (1)
α = θ (2)
r2 ≧ r1 (3)
R <r1 × sin α (4)
V ≧ L + r2 × cos α (5)

That is, the pitch A is set to be smaller than the width V of the inlet 6 in order to quickly transport the developer flowing in from the inlet 6. Further, when the developer transport member 17 is rotated, the flexible clog prevention member 21 is deformed so as to be wound around the rotary shaft 17a (more precisely, the large diameter portion 17d). The width L of the clogging prevention member 21 is set to be smaller than the pitch A and satisfy the formula (2) in order to fit between the conveying blades 17b so as not to be damaged by contact with the conveying blades 17b. . Furthermore, in order for the clogging prevention member 21 to enter the inlet 6 from the developer conveyance path 11 in an extended state and to project the outer end portion outward,
It is set so as to satisfy Expression (4). Further, the clogging prevention member 21 is set so as to satisfy the expression (5) so that the clogging prevention member 21 is not caught by the inflow port 6 and is not damaged.
The members denoted by reference numerals 2 to 21 constitute the developer conveying device 1 of the first embodiment.

(Operation of Example 1)
In the printer U as an example of the image forming apparatus of the first embodiment having the above-described configuration, when the toner of the developing devices Gy to Gk is consumed by the image forming operation, the toner cartridges TCy to T
Ck toner is supplied from the inlet 6. The supplied developer is transported and replenished by the rotation of the developer transport member 17 of the developer transport device 1.
The inflow port 6 according to the first exemplary embodiment is disposed with a slight inclination from the vertical direction, and the developer from the toner cartridges TCy to TCk is conveyed in a direction close to the horizontal direction, and does not easily drop in the direction of gravity and is clogged. There are things to do. In the developer transport device 1 of Example 1, the developer transport member 1
7 is rotated, the clogging prevention member 21 supported by the rotating shaft 17a enters the inflow port 6 or is bent so as to be wound around the rotating shaft 17a and retracts from the inflow port 6. When the clogging prevention member 21 enters the inlet 6 and the toner is clogged at the inlet 6, the clogged toner is destroyed. That is, the clogging is eliminated and the toner cartridges TCy to T
The toner is stably supplied from Ck to the developer conveying device 1.

FIG. 10 is an explanatory diagram of the length and positional relationship of the developer conveying member and the clogging preventing member according to the second embodiment of the present invention, and corresponds to FIG. 9 according to the first embodiment.
Next, an image forming apparatus according to a second embodiment of the present invention will be described. In the description of the second embodiment,
Constituent elements corresponding to the constituent elements of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The second 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.

In FIG. 10, the sizes and angles of the developer conveying member 17, the clogging preventing member 21, and the inflow port 6 of Example 2 are expressed by the following equations (1), (2), (3 ′), and (4 ′). ) And the relationship of the formula (5) are set.
V>A> L (1)
α = θ (2)
r2 <r1 (3 ')
R <r2 × sin α (4 ′)
V ≧ L + r2 × cos α (5)
In other words, the second embodiment is set to satisfy the expressions (1), (2), and (5) as in the first embodiment. Then, instead of Expression (3) and Expression (4), Expression (3 ′) and Expression (4
') Is set to satisfy. Therefore, when the upstream free length r1 is larger than the downstream free length r2, the clogging prevention member 21 enters the inlet 6 from the developer transport path 11 in an extended state, and therefore, the expression (4 ′ ) Is set to satisfy.

(Operation of Example 2)
In the printer U as an example of the image forming apparatus according to the second embodiment having the above-described configuration, the expression (1),
The clogging preventing member 21 satisfying the relations of the expressions (2), (3 ′), (4 ′), and (5) is:
As the developer transport member 17 rotates, the toner enters and retreats with respect to the inlet 6, and the toner clogged in the inlet 6 is collapsed to eliminate the clogging. That is, the image forming apparatus U of the second embodiment is also the first embodiment.
This has the same function as the image forming apparatus U.

FIG. 11 is an explanatory diagram of the length and positional relationship of the developer conveying member and the clogging preventing member according to the third embodiment of the present invention, and corresponds to FIG. 9 according to the first embodiment.
Next, an image forming apparatus according to a third embodiment of the present invention will be described. In the description of the third embodiment,
Constituent elements corresponding to the constituent elements of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The third 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.
In FIG. 11, in addition to the respective V, L, A, r1, r2, R, and α, the clogging preventing member 21 is provided.
The distance between the conveying blade 17b adjacent to the upstream side of the clogging prevention member 21 and the upstream end in the axial direction of the clogging prevention member 21 at a position where the clogging prevention member 21 is supported by the rotation shaft 17a is S1, and the clogging prevention member 21 is rotated by the rotation shaft 17a. When the distance between the conveyance blade 17b adjacent to the downstream side of the clogging prevention member 21 at the position supported by the clogging prevention member 21 and the downstream end in the axial direction of the clogging prevention member 21 is S2, the developer conveyance member 17 of Example 3 is used. The size and angle of the clogging prevention member 21 and the inlet 6 are related to the following formulas (1), (2 '), (3), (4), (5'), and (6). Is set to satisfy.
V>A> L (1)
α ≦ θ (2 ')
r2 ≧ r1 (3)
R <r1 × sin α (4)
V ≧ L + S2, (5 ′)
S2 ≧ r2 × sin (θ−α) / sinθ (6)

In other words, the third embodiment is set so as to satisfy the expressions (1), (3), and (4) as in the first embodiment. When the expression (2 ′) is satisfied, that is, when the angle α of the clogging prevention member 21 is smaller than the angle θ of the conveyance blade 17b, the clogging prevention member 21 contacts the conveyance blade 17b on the downstream side in the conveyance direction. Therefore, in order to prevent the clogging prevention member 21 from being damaged, it is set so as to satisfy Expression (6). Further, in order to prevent the clogging prevention member 21 from being pinched at the inlet 6 and being damaged, the formula (5) is replaced with the formula (
6) and the formula (5 ') are set.

(Operation of Example 3)
In the printer U as an example of the image forming apparatus according to the third embodiment having the above-described configuration, the expression (1),
The clogging prevention member 21 that satisfies the relations of the expressions (2 ′), (3), (4), (5 ′), and (6) corresponds to the inlet 6 according to the rotation of the developer conveying member 17. Entry and evacuation to the inlet 6
The clogged toner is broken and the clogging is eliminated. That is, the image forming apparatus U according to the third embodiment.
Has the same operation as the image forming apparatus U of the first embodiment.

FIG. 12 is an explanatory diagram of the length and positional relationship of the developer conveying member and the clogging preventing member according to the fourth embodiment of the present invention, and corresponds to FIG. 9 according to the first embodiment.
Next, an image forming apparatus according to a fourth embodiment of the present invention will be described. In the description of the fourth embodiment,
Constituent elements corresponding to the constituent elements of the first and third embodiments are denoted by the same reference numerals, and detailed description thereof is omitted. The fourth embodiment is different from the first and third embodiments in the following points, but is configured similarly to the first and third embodiments in other points.

In FIG. 12, the sizes and angles of the developer conveying member 17, the clogging preventing member 21, and the inflow port 6 of Example 4 are expressed by the following equations (1), (2 ″), (3), and (4). , Formula (5 ″), Formula (6
') Is set so as to satisfy the relationship.
V>A> L (1)
α> θ (2 ″)
r2 ≧ r1 (3)
R <r1 × sin α (4)
V ≧ L + S1, (5 ″)
S1 ≧ r1 × sin (α−θ) / sinθ (6 ′)

In other words, the fourth embodiment is set so as to satisfy the expressions (1), (3), and (4) as in the first embodiment. When the expression (2 ″) is satisfied, that is, when the angle α of the clogging prevention member 21 is larger than the angle θ of the conveyance blade 17b, the clogging prevention member 21 contacts the conveyance blade 17b on the upstream side in the conveyance direction. In order to prevent the clogging prevention member 21 from being damaged, it is set so as to satisfy the formula (6 ′), and the clogging prevention member 21 is sandwiched by the inlet 6 and is damaged. In order to prevent this, it is set so as to satisfy the expressions (6 ′) and (5 ′) instead of the expression (5).

(Operation of Example 4)
In the printer U as an example of the image forming apparatus according to the fourth embodiment having the above-described configuration, the expression (1),
The clogging prevention member 21 that satisfies the relationship of the formula (2 ″), the formula (3), the formula (4), the formula (5 ″), and the formula (6 ′) is an inflow port according to the rotation of the developer conveying member 17. 6 enters and retracts, and the toner clogged in the inflow port 6 is broken, and the clogging is eliminated. That is, the image forming apparatus U according to the fourth embodiment has the same operation as that of the image forming apparatus U according to the first embodiment.

(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 performed within the range of the summary of this invention described in the claim. It is possible. Modification examples (H01) to (H07) of the present invention are exemplified below.
(H01) In the above-described embodiment, the printer as the image forming apparatus has been exemplified. However, the present invention is not limited to this, and a FAX, a copying machine, or a multifunction machine having all or a plurality of functions may be used. Further, the image forming apparatus is not limited to a multi-color developing image forming apparatus, and may be configured by a monochromatic, so-called monochrome image forming apparatus. Further, the present invention is not limited to the configuration in which the image is transferred directly from the image carrier to the medium, and can also be applied to a configuration using an intermediate transfer body.

(H02) In the above-described embodiment, the clogging prevention member may have sufficient strength, or there may be a sufficient clearance for retraction between the developer transport member 17 and the developer transport path 11 to cause damage or the like. If not, the length and angle can be set so as not to satisfy the relations of the respective relational expressions. Conversely, corresponding to the clogging prevention member, a ring-shaped groove is formed in the developer transport path 11,
It is also possible to form a clearance gap in the developer conveyance path 11 by reducing the outer diameter of the conveyance blade 17b.
(H03) In the above-described embodiment, the developer conveying device for supplying a new developer has been exemplified. However, the present invention is not limited to this, and the present invention can also be applied to a developer conveying device that conveys a waste developer.

(H04) In the above-described embodiment, the developer transport path 11 is curved. However, it may be configured linearly. At this time, the developer conveying member 17 can also be made of a highly rigid material instead of a flexible resin material.
(H05) In the above-described embodiment, the case where the toner flows in the inclination direction close to the horizontal direction through the inlet 6 is illustrated, but the present invention is not limited to this, and the toner flows in the gravity direction or the inclination direction close to the gravity direction. It is applicable also to the structure to perform.
(H06) In the above-described embodiment, a plurality of developer transport paths 11 may be connected. At this time, a clogging prevention member can be provided on the inflow side of the connecting portion.

(H07) In the above embodiment, the relationship among α, θ, V, L, A, r1, r2, R, S1, S2 is preferably the relationship illustrated in the embodiment, but is not limited thereto. It can be changed according to the strength and combination of the materials, ease of breakage, design and specifications. For example, Example 3,
In FIG. 4, r1 and r2 have the same length, but it is also possible to satisfy r1 <r2 or r1> r2.

1 is a perspective explanatory view of an image forming apparatus according to a first embodiment of the present invention. FIG. 2 is an overall explanatory view of the image forming apparatus according to the first embodiment of the present invention. FIG. 3 is an explanatory perspective view of the image forming apparatus according to the first exemplary embodiment of the present invention with the side cover opened. FIG. 4 is an explanatory view showing a state in which a toner cartridge as an example of a developer container is attached and detached. FIG. 5 is an explanatory diagram of the developer conveying device according to the first exemplary embodiment of the present invention, FIG. 5A is an explanatory diagram viewed from an oblique rear side, and FIG. 5B is a diagram viewed from the direction of arrow VB in FIG. FIG. 6 is an explanatory diagram of the relationship between the developer conveying device and the developing device according to the first embodiment of the present invention. FIG. 7 is an enlarged explanatory view of a main part of the inlet portion of the developer conveying device according to the first embodiment of the present invention. FIG. 8 is an explanatory diagram of the developer conveying member according to the first embodiment of the present invention. FIG. 9 is an explanatory diagram of the length and positional relationship between the developer conveying member and the clogging preventing member according to the first embodiment of the present invention. FIG. 10 is an explanatory diagram of the length and positional relationship of the developer conveying member and the clogging preventing member according to the second embodiment of the present invention, and corresponds to FIG. 9 according to the first embodiment. FIG. 11 is an explanatory diagram of the length and positional relationship of the developer conveying member and the clogging preventing member according to the third embodiment of the present invention, and corresponds to FIG. 9 according to the first embodiment. FIG. 12 is an explanatory diagram of the length and positional relationship of the developer conveying member and the clogging preventing member according to the fourth embodiment of the present invention, and corresponds to FIG. 9 according to the first embodiment.

1 ... Developer transport device,
6 ... Inlet,
11 ... developer transport path,
17 ... conveying member,
17a ... rotating shaft,
17b ... conveying blade,
21 ... Clogging prevention member,
A: Pitch of conveying blade,
F ... Fixer,
Gy, Gm, Gc, Gk ... developing device,
L: Installation width of the clogging prevention member to the rotating shaft,
Py, Pm, Pc, Pk ... image carrier,
R: Distance from the center of the rotation axis to the inner wall of the developer conveyance path,
r1... free length of the clogging prevention member upstream in the developer transport direction,
r2: Free length of the clogging prevention member on the downstream side in the developer conveying direction,
S ... medium
S1 ... Distance between the conveying blade adjacent to the upstream side of the clogging prevention member and the upstream end in the axial direction of the clogging prevention member,
S2: Distance between the conveying blade adjacent to the downstream side of the clogging prevention member and the downstream end in the axial direction of the clogging prevention member,
T1y, T1m, T1c, T1k ... transfer device,
U: Image forming apparatus,
V: width in the developer conveyance direction at the inlet,
α: Inclination angle with respect to the rotation axis of the clogging prevention member,
θ: The inclination angle of the conveying blade with respect to the rotation axis.

Claims (5)

A developer transport path having an inlet through which the developer flows;
A conveyance member having a rotation shaft and a conveyance blade supported by the rotation shaft, and disposed in the developer conveyance path to convey the developer;
A clogging prevention member that is supported by the rotation shaft and has a flexibility that allows a tip portion to enter and retreat into the inflow port as the rotation shaft rotates.
With
The width of the inflow port in the developer conveyance direction is V, the pitch that is the interval between adjacent blades in the axial direction of the conveyance blade is A, and the center of the rotation shaft to the inner wall of the developer conveyance path of the inflow port portion. R is the distance, L is the mounting width of the clogging prevention member to the rotating shaft, r1 is the free length of the clogging prevention member upstream in the developer conveyance direction, and the clogging prevention member is downstream in the developer conveyance direction. When the free length is r2, the inclination angle of the clogging prevention member with respect to the rotation axis is α, and the inclination angle of the conveying blade with respect to the rotation axis is θ,
V>A> L,
α = θ,
r2 ≧ r1,
R <r1 × sin α,
V ≧ L + r2 × cos α,
A developer carrying device satisfying the requirements. A developer transport path having an inlet through which the developer flows;
A conveyance member having a rotation shaft and a conveyance blade supported by the rotation shaft, and disposed in the developer conveyance path to convey the developer;
A clogging prevention member that is supported by the rotation shaft and has a flexibility that allows a tip portion to enter and retreat into the inflow port as the rotation shaft rotates.
With
The width of the inflow port in the developer conveyance direction is V, the pitch that is the interval between adjacent blades in the axial direction of the conveyance blade is A, and the center of the rotation shaft to the inner wall of the developer conveyance path of the inflow port portion. R is the distance, L is the mounting width of the clogging prevention member to the rotating shaft, r1 is the free length of the clogging prevention member upstream in the developer conveyance direction, and the clogging prevention member is downstream in the developer conveyance direction. When the free length is r2, the inclination angle of the clogging prevention member with respect to the rotation axis is α, and the inclination angle of the conveying blade with respect to the rotation axis is θ,
V>A> L,
α = θ,
r2 <r1,
R <r2 × sin α,
V ≧ L + r2 × cos α,
A developer carrying device satisfying the requirements. A developer transport path having an inlet through which the developer flows;
A conveyance member having a rotation shaft and a conveyance blade supported by the rotation shaft, and disposed in the developer conveyance path to convey the developer;
A clogging prevention member that is supported by the rotation shaft and has a flexibility that allows a tip portion to enter and retreat into the inflow port as the rotation shaft rotates.
With
The width of the inflow port in the developer conveyance direction is V, the pitch that is the interval between adjacent blades in the axial direction of the conveyance blade is A, and the center of the rotation shaft to the inner wall of the developer conveyance path of the inflow port portion. R is the distance, L is the mounting width of the clogging prevention member to the rotating shaft, r1 is the free length of the clogging prevention member upstream in the developer conveyance direction, and the clogging prevention member is downstream in the developer conveyance direction. The free length is r2, the inclination angle of the clogging prevention member with respect to the rotation axis is α, the inclination angle of the conveying blade with respect to the rotation axis is θ, and the clogging prevention member at a position where the clogging prevention member is supported by the rotation axis. When the distance between the conveying blade adjacent to the downstream side of the clogging and the downstream end in the axial direction of the clogging prevention member is S2,
V>A> L,
α ≦ θ,
S2 ≧ r2 × sin (θ−α) / sinθ,
V ≧ L + S2,
A developer carrying device satisfying the requirements. A developer transport path having an inlet through which the developer flows;
A conveyance member having a rotation shaft and a conveyance blade supported by the rotation shaft, and disposed in the developer conveyance path to convey the developer;
A clogging prevention member that is supported by the rotation shaft and has a flexibility that allows a tip portion to enter and retreat into the inflow port as the rotation shaft rotates.
With
The width of the inflow port in the developer conveyance direction is V, the pitch that is the interval between adjacent blades in the axial direction of the conveyance blade is A, and the center of the rotation shaft to the inner wall of the developer conveyance path of the inflow port portion. R is the distance, L is the mounting width of the clogging prevention member to the rotating shaft, r1 is the free length of the clogging prevention member upstream in the developer conveyance direction, and the clogging prevention member is downstream in the developer conveyance direction. The free length is r2, the inclination angle of the clogging prevention member with respect to the rotation axis is α, the inclination angle of the conveying blade with respect to the rotation axis is θ, and the clogging prevention member at a position where the clogging prevention member is supported by the rotation axis. When the distance between the conveying blade adjacent to the upstream side of the clogging and the axial upstream end of the clogging prevention member is S1,
V>A> L,
α> θ,
S1 ≧ r1 × sin (α−θ) / sinθ,
V ≧ L + S1,
A developer carrying device satisfying the requirements. An image carrier,
A developing device for developing the latent image on the surface of the image carrier into a visible image;
The developer conveying device according to any one of claims 1 to 4 , wherein a new developer is conveyed to the developing device;
A transfer device for transferring a visible image developed by the developing device to a medium;
A fixing device for fixing the visible image transferred to the medium;
An image forming apparatus comprising:

Images