JP4262005B2 - Developer supply device and image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a developer replenishing device and an image forming apparatus used in, for example, an electrophotographic copying machine.
[0002]
[Prior art]
This type of image forming apparatus forms an electrostatic latent image on a photosensitive drum as an image carrier, and develops the electrostatic latent image with a developing device. A toner bottle as a toner replenishing device is attached to the developing device, and toner is replenished by the toner bottle.
[0003]
The toner bottle is connected by inserting the tip cap portion side into the coupling constituting the driving portion. An opening is provided in the peripheral wall portion of the tip cap portion of the toner bottle, and a toner supply port is provided in the peripheral wall portion of the coupling. When the front end cap portion side of the toner bottle is inserted into the coupling, the opening portion faces the toner supply port of the coupling.
[0004]
When the toner is replenished, the toner bottle is rotated with the rotation of the coupling, and when the opening and the toner supply port are positioned on the lower side, the toner in the toner bottle is removed from the toner supply port through the opening by its own weight. Dropped and replenished into the developer.
[0005]
By the way, since the front end cap portion of the toner bottle is inserted and fitted into the coupling in a sealed state, the pressure in the coupling rapidly changes when the toner bottle is pulled out.
[0006]
[Problems to be solved by the invention]
However, conventionally, since the hole provided in the coupling is only the toner supply port, a strong suction force acts on the toner supply port when the toner bottle is pulled out. For this reason, there is a problem in that the toner adhering to the peripheral edge of the toner supply port is sucked into the interior from the toner supply port, and the inside of the coupling becomes dirty.
[0007]
The present invention has been made paying attention to the above circumstances, and an object of the present invention is to provide a developer replenishing device that prevents the developer from being sucked from the developer supply port of the coupling when the developer storage container is pulled out. An object is to provide an image forming apparatus.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the invention described in claim 1 is provided integrally with a coupling having a developer supply port in the peripheral wall portion and a predetermined interval along the inner peripheral wall surface in the coupling. was a Setsukabe specifications, the circumferential direction into a plurality provided along the inner peripheral wall surface of the partition wall, housing a hole portion opening amount that the total is larger than the opening amount of the developer supply opening, a developer The front end side is inserted into the partition wall in an airtight and detachable manner, and a developer replenishing port facing the hole of the partition wall is provided in the front end peripheral wall portion, and the hole from the developer replenishing port And a developer storage container that replenishes the replenished part with the developer via the developer supply port.
[0009]
According to a fifth aspect of the present invention, there is provided image forming means for forming an electrostatic latent image on an image bearing member, and development to supply a developer to the electrostatic latent image formed by the image forming means to form a developer image. And a developer replenishing means for replenishing the developer to the developing means. The developer replenishing means includes a coupling having a developer supply port in the peripheral wall portion, and an inner peripheral wall surface in the coupling. and Setsukabe specifications provided integrally at predetermined intervals along the plural provided along the circumferential direction thereof on the inner peripheral wall surface of the partition wall, an opening amount of opening of the total of the developer supply opening A hole that is larger than the amount and a developer are accommodated, and the tip end side is inserted into the partition wall in an airtight and detachable manner, and the developer is opposed to the hole portion of the partition wall in the tip peripheral wall portion A developer supply port, from which the developer is supplied through the hole and the developer supply port. Comprising a developer container for supplying the means.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.
[0011]
FIG. 1 schematically shows an internal configuration of an electrophotographic copying machine as an image forming apparatus according to an embodiment of the present invention.
[0012]
In FIG. 1, reference numeral 1 denotes a photosensitive drum as an image carrier, and this photosensitive drum 1 is rotatably provided in the direction of an arrow. A charging charger 2 for charging the surface of the photosensitive drum 1 sequentially along the rotation direction, a developing unit 3 for developing the electrostatic latent image on the photosensitive drum 1 with toner, around the photosensitive drum 1 in order. A transfer charger 4 for transferring a toner image on the photosensitive drum 1 to a sheet, a cleaning device 5 for removing residual toner on the photosensitive drum 1, and a static eliminator 6 for removing residual potential on the photosensitive drum 1 are provided. ing.
[0013]
Further, an exposure unit 7 as an image forming unit that forms an electrostatic latent image by irradiating the surface of the photosensitive drum 1 with image information light 7 a is opposed to the photosensitive drum 1. A toner replenishing device 9 as a developer replenishing means for replenishing toner to the developing unit 3 is provided above the developing unit 3. On the lower side of the exposure unit 7, a fan 11 for discharging the ozone generated from the charging charger 2 by blowing air and cooling the toner replenishing device 9 is provided.
[0014]
On the other hand, a paper feed cassette 12 for storing paper P is provided below the developing unit 3, and the paper P in the paper feed cassette 12 is taken out by the rotation of the pickup roller 13. The taken-out paper is conveyed upward by the conveyance system 15.
[0015]
In the transport system 15, a paper feed / separation roller 16 that sequentially feeds the paper one by one along the paper transport direction, a transport roller pair 17 that sandwiches and transports the paper, and a registration roller pair that aligns the paper. 18, the transfer charger 4 described above, a fixing device 19 for fixing the transferred toner image on the paper, a paper discharge roller pair 20 for discharging the paper, and a paper discharge tray 21 for receiving the paper to be discharged.
[0016]
Next, an image forming operation of the above-described image forming apparatus will be described.
[0017]
At the time of image formation, first, the surface of the photosensitive drum 1 is uniformly charged by the charging charger 2, and image information light 7 a is irradiated onto the charged photosensitive drum 1 from the exposure unit 7 to form an electrostatic latent image. It is formed. This electrostatic latent image is sent to the developing device 3 by the rotation of the photosensitive drum 1 and is developed by supplying toner from the developing device 3. The developed toner image is moved by the rotation of the photosensitive drum 1 and is opposed to the transfer charger 4.
[0018]
On the other hand, at this time, the paper P is supplied from the paper feed cassette 12, and the paper P is sent to the image transfer portion 2a between the photosensitive drum 1 and the transfer charger 4 to transfer the toner image on the photosensitive drum 1. Is done. After this transfer, the paper P is peeled off from the photosensitive drum 1 and sent to the fixing device 19, where the toner image is heated and pressurized and fixed on the paper P. After this fixing, the paper P is discharged onto the paper discharge tray 21 via the paper discharge roller pair 20. Thereafter, the image forming operation is repeated in the same manner.
[0019]
FIG. 2 is a side sectional view showing the toner replenishing device 9.
[0020]
In FIG. 2, reference numeral 25 denotes a toner bottle as a developer storage container for storing toner t as a developer. The toner bottle 25 is rotationally driven with its leading end connected to a driving device 26 as driving means.
[0021]
The driving device 26 includes a cylindrical coupling 29 in which the front end cap portion 28 of the toner bottle 25 is inserted and connected in a detachable manner. The coupling 29 is rotatably provided in a cylindrical casing 30. An opening 30 b is formed on the lower surface side of the peripheral wall portion of the casing 30.
[0022]
A mouth part 29 a projects from the center of the inner bottom of the coupling 29. The mouth portion 29a has a circular outer peripheral surface and a polygonal inner peripheral surface. The mouth portion 29a is rotatably inserted into an attachment hole 30a formed in the casing 30. A toner supply port 29 b serving as a developer supply port is formed in the peripheral wall portion of the coupling 29.
[0023]
The coupling 29 is in a fixed position when the toner bottle 25 is inserted, that is, the toner supply port 29b is positioned on the upper side. At this fixed position, the toner bottle 25 is inserted into the coupling 29, and an opening 28a serving as a developer replenishing port faces the toner supply port 29b.
[0024]
A coupling gear 32 is slidably mounted in the mouth part 29 a of the coupling 29. The coupling gear 32 has a shaft portion 32a having a polygonal cross section, and one end portion side of the shaft portion 32a is slidably inserted into the mouth portion 29a. A gear portion 32c projects from the other end portion of the shaft portion 32a via a disk-shaped plate 32b.
[0025]
A drive gear 34 as a drive unit is engaged with the gear unit 32c. A drive motor (not shown) is connected to the drive gear 34.
[0026]
3 is a front sectional view showing the above-described coupling 29, and FIG. 4 is a side sectional view thereof.
[0027]
A partition wall 35 is integrally provided inside the coupling 29 with a predetermined interval along the inner peripheral wall surface thereof. A plurality of holes 35a are formed in the peripheral wall of the partition wall 35 along the circumferential direction. The total opening amount of the plurality of hole portions 35a is larger than the opening amount of the toner supply port 29b.
[0028]
On the other hand, the opening 28 a of the tip cap portion 28 of the toner bottle 25 is opened and closed by a shutter 36. The shutter 36 is slidably attached to a projecting portion 37 protruding in a radial manner on the outer peripheral wall portion of the tip cap portion 28, and is urged in a direction to close the opening portion 28a by a spring (not shown).
[0029]
A guide portion 40 is formed on the partition wall 35 of the coupling 29 described above so that the projection 37 of the toner bottle 25 is inserted and guided, and the opening 28 a of the tip cap portion 28 is opposed to the toner supply port 29 b. .
[0030]
The dimension L1 in the depth direction of the coupling 29 is larger than the dimension L2 in the depth direction of the partition wall 35, and the dimension L4 to the hole 35a is smaller than the dimension L3 to the opening end of the coupling 29. It is arranged at the position.
[0031]
Next, the toner supply operation will be described.
[0032]
In the state shown in FIG. 2, when the drive motor is driven and the drive gear 34 is driven to rotate, the coupling gear 32 is rotated via the gear portion 32c. As a result, the coupling 29 is rotated and the toner bottle 25 is rotated. As a result of this rotation, as shown in FIG. 5, when the toner supply port 29 b of the coupling 29 faces the opening 30 b of the casing 30, the toner t in the toner bottle 25 is transferred to the opening 28 a of the tip cap 28 and the toner supply port. As indicated by an arrow through 29b, the toner is dropped from the opening 30b of the casing 30 and supplied into the developing device 3.
[0033]
When the toner in the toner bottle 25 is used due to the toner replenishment described above, it is necessary to replace the toner bottle 25 with a new one.
[0034]
In this case, after the used toner bottle 25 is pulled out from the coupling 29, a new toner bottle 25 is inserted into the coupling 29.
[0035]
By the way, since the front end cap portion 28 of the toner bottle 25 is hermetically inserted into and connected to the partition wall 35 of the coupling 29, when the toner bottle 25 is pulled out to assist in FIG. The inside becomes a negative pressure state. However, at this time, the air existing between the coupling 29 and the partition wall 35 is sucked into the partition wall 35 from the hole 35a of the partition wall 35 as indicated by an arrow. This suction reduces the suction force acting on the toner supply port 29b of the coupling 29, so that the toner remaining on the peripheral edge of the toner supply port 29b is not sucked from the toner supply port 29b. Accordingly, it is possible to reliably prevent toner contamination in the coupling 29.
[0036]
When inserting a new toner bottle 25 into the coupling 29, first, as shown in FIG. 7, the front end cap portion 28 of the toner bottle 25 is partitioned along the inner peripheral surface of the coupling 29. Insert it to the front end side. Next, from this state, the toner bottle 25 is rotated in the circumferential direction along the inner peripheral surface of the coupling 29, and the toner bottle 25 is moved in the back direction at a position where the protruding portion 37 faces the guide portion 40 of the partition wall 35. Push in. As a result, the protruding portion 27 of the tip cap portion 28 of the toner bottle 25 is inserted into the guide portion 40, and the shutter 36 abuts against a stopper (not shown) during the insertion, and the opening 28 a is a hole in the partition wall 35. It faces the toner supply port 29b of the coupling 29 through the part 35a. When the coupling 29 is rotated from this state and the toner supply port 29b is positioned on the lower side, the toner in the toner bottle 25 is dropped downward through the opening 28a of the tip cap portion 28 by its own weight and is replenished. .
[0037]
As described above, when the toner bottle 25 is pulled out, the air between the coupling 29 and the partition wall 35 is sucked into the inside through the hole 35a of the partition wall 35, so that it acts on the toner supply port 29b of the coupling 29. The air suction force can be reduced, and the toner is not sucked from the toner supply port 29b. Therefore, it is possible to reliably prevent toner contamination of the coupling 29.
[0038]
When a new toner bottle 25 is inserted into the coupling 29, the toner bottle 25 is inserted along the inner peripheral surface on the front end side of the coupling 29, and then the toner is simply rotated in the circumferential direction. The bottle 25 can be positioned, and the toner bottle 25 can be easily inserted.
[0039]
FIG. 8 is a sectional view showing a coupling 45 according to another embodiment of the present invention.
[0040]
In this embodiment, a plurality of ribs 47 serving as support members project between the inner peripheral surface portion of the coupling 45 and the outer peripheral surface portion of the partition wall 46 in the circumferential direction, and the plurality of ribs 47a and 47b. , 47c, the partition wall 46 is supported.
[0041]
The rib 47a is positioned on the opposite side of the toner supply port 45a of the coupling 45, and the other ribs 47b and 47c are a straight line S connecting the toner supply port 45a and the rib 47a and straight lines S1 and S2 passing through the center of the coupling 45. Is arranged within a range of ± 45 degrees.
[0042]
The ribs 47 a to 47 c are formed with a length equal to the depth L 2 of the partition wall 46 and do not protrude forward from the opening end of the partition wall 35. Thus, when the toner bottle 25 is inserted, the tip cap portion 28 can be smoothly inserted without coming into contact with the ribs 47a to 47c.
[0043]
According to this embodiment, the strength of the partition wall 46 can be increased, and there is an advantage that the positional relationship between the toner supply port 45 and the opening portion 28a of the tip cap portion 28 of the toner bottle 25 can be favorably maintained.
[0044]
The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the gist.
[0045]
【The invention's effect】
As described above, the present invention can reduce the suction force acting on the developer supply port of the coupling when the developer storage container is pulled out, and reduces the suction of the developer from the developer supply port as much as possible. It is possible to produce an effect of preventing dirt.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing an internal configuration of an electrophotographic copying machine according to an embodiment of the present invention.
FIG. 2 is a side sectional view showing a toner replenishing device provided in the electrophotographic copying machine.
FIG. 3 is a front sectional view showing a coupling of the toner replenishing device.
FIG. 4 is a side sectional view showing the coupling.
FIG. 5 is a cross-sectional view showing a state where toner is supplied by the toner supply device.
FIG. 6 is a view showing an operation of pulling out the toner bottle.
FIG. 7 is a diagram illustrating an operation of inserting the toner bottle into the coupling.
FIG. 8 is a view showing a modification of the coupling.
[Explanation of symbols]
t ... toner (developer), 3 ... replenished portion (developing means), 7 ... exposure unit (image forming means), 9 ... toner replenishing device (developer replenishing means), 25 ... toner bottle (developer storage container) , 29 ... coupling, 29b ... toner supply port (developer supply port), 35a ... hole, 35 ... partition wall, 37 ... projection, 40 ... guide part, 45 ... coupling, 46 ... partition wall, 47a- 47c ... rib (supporting member).

Claims (5)

A coupling having a developer supply port on the peripheral wall,
And Setsukabe specifications provided integrally at predetermined intervals along the inner wall surface to the cup ring,
A plurality of holes provided on the inner peripheral wall surface of the partition wall in the circumferential direction, the total opening amount being larger than the opening amount of the developer supply port,
The developer is stored, and the tip end side is inserted in the partition wall in an airtight and detachable manner, and the developer peripheral opening has a developer supply port facing the hole of the partition wall. A developer replenishing device comprising: a developer storage container for replenishing a developer to a replenished portion from the opening through the hole and a developer supply port. The developer storage container has a protruding portion protruding in a radial method on the outer peripheral wall portion at the tip,
The partition wall has a guide portion that fits the protrusion portion of the outer peripheral wall portion of the tip of the developer container and guides the developer replenishing port to face the developer supply port by sliding in the insertion direction. The developer replenishing device according to claim 1.   The opening end of the partition wall is positioned on the back side in the coupling with respect to the opening end of the coupling, and the developer storage container is inserted along the inner peripheral surface of the coupling to the front of the partition wall. 2. The developer replenishing device according to claim 1, wherein the developer replenishing device is positioned by being rotated along a circumferential direction of the coupling.   The support member for supporting the partition wall is provided between the inner peripheral surface of the coupling and the outer peripheral surface of the partition wall, which is located on the opposite side of the developer supply port of the coupling. 2. The developer supply device according to 1. Image forming means for forming an electrostatic latent image on the image carrier;
Developing means for supplying a developer to the electrostatic latent image formed by the image forming means to form a developer image;
A developer replenishing means for replenishing the developer to the developing means;
The developer supply means
A coupling having a developer supply port on the peripheral wall,
And Setsukabe specifications provided integrally at predetermined intervals along the inner wall surface to the cup ring,
A plurality of holes provided on the inner peripheral wall surface of the partition wall in the circumferential direction, the total opening amount being larger than the opening amount of the developer supply port,
The developer is stored, and the tip end side is inserted in the partition wall in an airtight and detachable manner, and the developer peripheral opening has a developer supply port facing the hole of the partition wall. An image forming apparatus comprising: a developer container that replenishes developer to the developing unit from the opening through the hole and a developer supply port.

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