JP3271338B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for forming an image on a sheet material such as a printer and a facsimile, and more particularly, to toner conveyance and toner replenishment of an electrophotographic image forming apparatus.

[0002]

2. Description of the Related Art Generally, in an image forming apparatus using an electrophotographic system, a latent image is formed by uniformly charging a surface of a photoreceptor and exposing the image to a latent image. The toner image is transferred to paper or the like to form an image. The toner image transferred onto the paper is output after being fixed by heat or the like, and the transferred photoreceptor is repeatedly used by removing the untransferred toner image by a cleaning unit.

In this type of image forming apparatus which is generally put into practical use, the transfer efficiency of a toner image to paper or the like is about 70 to 95%.
In the cleaning means, 5 to 30% of the toner is collected. In the case of the method in which the toner collected by the cleaning means is discarded, the running cost is high because the amount of toner used is increased, a container for discarding the toner is required, and the operation of discarding the toner is troublesome. Further, since there is a problem that the surroundings may be stained with toner during this operation, many systems have been proposed in which the toner collected by the cleaning unit is transported to the developing unit and reused.

Further, since toner is consumed by the developing means,
In order to continuously form an image by replenishing the reduced toner, a number of methods have been proposed in which a toner container for storing the toner is provided separately from the developing unit, and the toner is transported from the toner container to the developing unit.

For example, US Pat. No. 3,643,077 suggests that toner collected by cleaning means is transported to a developing unit, and US Pat. No. 3,67,889.
In the specification of Japanese Patent No. 6, as a specific means for transporting the toner collected by the cleaning means to the developing section, a method of moving a ball chain conveyor in which hollow balls are connected in a daisy chain in a tube connecting the cleaning means and the developing means is known. It has been disclosed.

In Japanese Patent Application Laid-Open No. 55-45012, the toner collected by the cleaning means is conveyed to the outside of the widthwise image forming area of the photoreceptor by a screw conveyer and provided in the developing means to form the image in the widthwise direction of the photoreceptor. A method is disclosed in which a toner is reused by being guided by a coil spring belt to a stirring roll extended outside the region. If a coil spring is used to transport the toner, the coil spring can be used as a flexible chain, and the aggregation state of the toner can be released by contraction or vibration of the coil spring.

Japanese Patent Application Laid-Open No. 61-249061 discloses a conveying means for guiding toner collected by a cleaning means to a developing means to reuse the toner, a toner in a toner container to the developing means, There is disclosed a toner conveyance system in which a conveyance unit for performing replenishment is partially used. Sharing the toner conveyance path has a great effect on simplification and downsizing of the apparatus.

[0008]

However, in the above-mentioned prior art, the ball chain conveyor disclosed in U.S. Pat. No. 3,678,896 has a problem that the space occupied by the toner in the transfer tube is limited, the transfer efficiency is low, and the transfer efficiency in the tube is low. There is a disadvantage that the toner leaking into the tube is pressed against the inner wall of the tube by the ball chain and solidified to cause toner jam.
Japanese Patent Laid-Open No. 12 discloses that a coil spring belt is used for conveying toner. However, a plurality of conveying means are provided for conveying the toner from the cleaning means to the developing means. Therefore, there is a disadvantage that toner conveyance failure and leakage are likely to occur. JP 6
Also in the toner conveying method disclosed in Japanese Patent Application Laid-Open No. 1-249061, the conveying mechanism is not sufficiently simplified, so that toner conveyance failure or leakage is likely to occur at a coupling mechanism portion of a plurality of conveying means, and toner replenishment is required. It is necessary to control the rotation of the screw roller based on a signal from the density control means, and the mechanism for controlling the apparatus has a disadvantage that the mechanism is complicated.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to propose a new toner conveyance and toner replenishment method which does not have the above-mentioned disadvantages. It is to provide a forming device.

[0010]

According to the present invention, there is provided an image forming apparatus comprising: developing means for developing a latent image formed by exposing a photoreceptor to develop a latent image; and toner consumed by the developing means. A toner container for storing toner for replenishing the toner, and a toner conveying unit that circulates and moves in communication with the developing unit and the toner container, a rotation shaft of a driving unit that drives the toner conveying unit. And the rotation axis of the stirring means for stirring the toner inside the toner container is the same.

The image forming apparatus according to the present invention is characterized in that the stirring means for stirring the toner in the toner container has means for generating an upward toner conveying force.

[0012]

[0013]

The inventors of the present invention have proposed a single toner unit in order to improve the disadvantages of the conventional toner conveying unit, such as the complicated and inconvenient toner conveyance at the connecting mechanism of a plurality of conveying units, which is likely to cause leakage. A new toner transport mechanism that circulates the transport means has been devised.

That is, the toner conveying means is circulated, and the developing means which needs to supply the toner, the toner container for replenishing the toner, and the cleaning means which needs to collect the toner are circulated along the circulating movement path. A simple single conveying means can be provided by providing the toner conveying means to absorb and release toner in relation to the amount of toner in each part and the amount of toner being conveyed to the toner conveying means. , It is possible to automatically perform all toner conveyance and toner supply of the image forming apparatus.

The inventors of the present invention manufactured a circulating toner transport mechanism and conducted an experiment. When the experiment was carried out, very good toner transport results were obtained initially. In some cases, agglomeration of the toner being conveyed to the conveyance unit and toner clogging of the circulation movement path of the toner conveyance unit occur. The present inventors have further developed a toner transport mechanism in order to improve such problems, and have repeated experiments. The configuration disclosed in the present invention can realize a new toner transport mechanism having excellent long-term reliability. It was confirmed.

According to the configuration of the present invention, in which the toner conveying means has a conveyance restricting means for narrowing a space for conveying the toner in the circulation moving path of the toner conveying means, when the circulating toner passes through the conveying restricting means portion, , The toner is prevented from gradually aggregating.

Further, by providing a means for communicating the toner carrying means and the toner container in a portion where the space for carrying the toner carrying means is narrowed by the carrying restricting means, the toner on the moving path from the toner container to the toner carrying means is provided. Is moved by the conveyance restricting means to prevent aggregation, so that the toner is stably supplied from the toner container. Further, since the space in which the toner is supplied from the toner container by the toner conveying means is narrowed by the conveying restricting means, the toner conveying means does not become full of toner, and the toner may be clogged in the circulation conveying path. Can be prevented.

Further, since the conveyance restricting means is a driving means for the toner conveying means, the above-mentioned effect can be realized without requiring the addition of a new mechanism.

Further, since the rotation axis of the driving means for driving the toner conveying means and the rotation axis of the stirring means for stirring the toner inside the toner container are the same, the mechanism for easily stirring the toner conveying mechanism and the inside of the toner container is simple. In addition to the fact that the conveyance restricting means is a driving means of the toner conveying means, the toner conveying means communicates with the toner container in a portion where the space for conveying the toner conveying means is narrowed. This can be easily realized in a state where the space utilization efficiency in the image forming apparatus is high.

Further, the agitating means for agitating the toner in the toner container has means for generating an upward toner conveying force, so that the toner from the toner container generated by the weight of the toner in the toner container to the toner conveying means is transferred to the toner conveying means. The supply pressure is reduced by the upward toner conveying force by the stirring means,
The supply of the toner to the toner conveying means is performed stably, so that the toner is prevented from being clogged in the circulation conveyance path.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The image forming apparatus of the present invention will be described in detail below with reference to embodiments.

FIG. 1 is a sectional view of a main part of an image forming apparatus according to an embodiment of the present invention. First, an image forming process of the apparatus will be described.

The photosensitive drum 1 is formed by forming a photosensitive layer made of an organic photosensitive member on a conductive substrate made of an aluminum drum. The charging roller 2 is driven by the photosensitive drum 1 rotating in the direction of arrow 1a. Is charged. The charging roller 2 is pressed toward the photosensitive drum 1 by a pressing mechanism (not shown), and a bias is applied.

Next, a light beam emitted from a laser emitting device (not shown), scanned by a scanning mirror 41 rotated by a scanning motor 42, and incident on the photosensitive drum 1 by a lens 43 and a mirror 44, Image exposure is performed on the upper surface to form a latent image.

Next, the toner in the storage section 14 for storing the toner in the developing section 10 is coated on the surface of the rotating developing roller 11 by the supply roller 13 which rotates while stirring the toner. The toner coated on the developing roller 11 is made of an elastic material such as a stainless steel plate, and rubs against the regulating blade 12 which is in contact with the outer periphery of the developing roller 11, whereby the toner is thinned and triboelectrically charged. A bias is applied to the developing roller 11, and the thinned toner layer is conveyed to the photosensitive drum 1, and the developing roller 11 and the photosensitive drum 1 are pressed against each other to form a latent image on the photosensitive drum 1 at a nip. Reversal development is performed.

Next, the toner image developed on the photosensitive drum 1 is transferred toward the photosensitive drum 1 by a pressing mechanism (not shown) and applied with a bias having a polarity opposite to that of the toner image on the photosensitive drum 1. The image is transferred onto the recording paper 3 conveyed between the roller 5 and the photosensitive drum 1. After the recording paper 3 is sent to the transfer portion by the paper feed roller 4 and receives the transfer of the toner image, the toner image is fixed by heating by the fixing roller 6 and is discharged by the discharge roller 7 in the direction of arrow 3a. You.

Next, in the cleaning section 20, the toner remaining after transfer is scraped off by the cleaning blade 21 which is in pressure contact with the photosensitive drum 1, and the cleaned photosensitive drum 1 can be shifted to the next image forming process again. .

The transport member 31 is circulating and moves.
The toner in the storage unit 14 which is consumed and reduced in the developing unit 10 due to the image formation decreases almost at the same time as the developing unit 1 decreases.
The toner conveyed by the conveying member 31 moving inside the cleaning unit 20 is automatically replenished by falling, and the toner scraped off by the cleaning unit 20 is removed by the cleaning unit 2.
The toner is dropped on the transporting member 31 moving in the area 0 and transported, and is used for toner supply in the developing unit 10.

FIG. 2 is a view showing the toner conveying mechanism in the embodiment of FIG. 1. FIG. 2 (a) is a top sectional view of the toner conveying mechanism of the present invention, and FIG. 2 (b) is FIG. FIG. 3 is a side sectional view of a section indicated by an arrow b, and FIG. 3 is a perspective view showing a shape of the stirring member 37 shown in FIG. The toner transport mechanism of the embodiment shown in FIG. 1 will be described in more detail with reference to FIGS.

The conveying member 31 is a coil spring,
In the direction a, the drive is provided by the drive gear 32 to which the drive is transmitted from the drive shaft 33, and circulates through the supply window 34 communicating with the toner container 35, the developing unit 10, and the cleaning unit 20 sequentially. By driving the coil spring, which is the conveying member 31, by engaging the groove of the drive gear 32 with the element wire of the coil spring, the teeth of the drive gear 32 are engaged in the space for conveying the toner in the coil spring during driving. Thus, the transporting space of the coil spring, which is the transporting member 31, is narrowed, and the transported toner is forcibly moved, so that the aggregation of the transported toner is prevented.

The circulating transport member 31 first passes through a supply window 34 communicating with a toner container 35 which is a means for supplying toner. The toner container 35 is disposed above the circulating movement path of the transport member 31, and the toner in the toner container 35 is agitated by a stirring member 37 to which drive is transmitted from a drive shaft 33.
And is in a fluidized state. The toner container 35 is provided with a lid member 36, and the toner container 3
5 can be supplied with toner from outside.

When the transport member 31 passes through the supply window 34,
When the conveying member 31 is not filled with the toner, the toner in the toner container 35 falls from the supply window 34 to the conveying member 31. However, since the conveying space of the conveying member 31 is narrowed by the drive gear 32, Even if the toner drops from the container 35, the amount of toner in the conveying member 31 is kept smaller than the amount of toner that can be originally conveyed. Further, as shown in FIG. 3, the agitating member 37 is provided with an inclined surface 38 for generating an upward conveying force on the toner in the toner container 35 as the toner is rotated. The toner is prevented from being pushed into the conveying member 31 by the pressure due to the weight, and the toner conveying amount of the conveying member 31 is maintained at an appropriate amount. The angle of the inclined surface 38 inclined with respect to the plane perpendicular to the rotation axis is preferably equal to or less than the angle of repose of the toner in order to generate a favorable upward conveying force.

On the other hand, when the transport member 31 is circulated to the supply window 34 in a state of being filled with the toner, the transport member 3
When the transfer space is narrowed by the drive gear 32, the toner inside the transfer member 31 is pushed out and moves to the supply window 34 which is a movable space. Here, an upward conveying force is applied to the toner in the toner container 35 above the toner supply window 34 by the inclined surface 38 of the stirring member 37, and the toner is pushed out of the conveying member 31 to the supply window 34 by the drive gear 32. The toner moves to the toner container 35 without clogging the supply window 34. Conveying member 3 circulating to supply window 34 in a state filled with toner
1 moves a part of the toner being conveyed when passing through the supply window 34 by the above operation to the toner container 35, and passes through the supply window 34 with the toner conveyance amount being maintained at an appropriate amount.

The transport member 31 transporting a fixed amount of toner through the supply window 34 moves away from the drive gear to the developing unit 10. When the amount of toner in the storage unit 14 that is in contact with the conveying member 31 is not stored in the developing unit 10,
The toner transported to the transport member 31 falls into the storage unit 14. The conveying member 31 traverses the developing unit 10 in the width direction of the image formation, and the toner in the storage unit 14 is conveyed by the conveying member 31.
When the amount of toner that is in contact with the conveying member 31 is not stored, the toner that is being conveyed falls, and when the amount of toner that is in contact with the conveying member 31 is stored, the toner that is being conveyed is held and moved. Therefore, the amount of toner in the storage unit 14 is substantially constant in the width direction of image formation due to the circulating movement of the conveying member 31.

The transporting member 31 having passed through the supply window 34 and having the toner transporting amount adjusted and having the toner dropped in the developing unit 10 as necessary, is guided inside the casing and changes direction to pass through the cleaning unit 20. I do. The toner scraped off by the cleaning blade 21 in the cleaning unit 20 falls on the conveying member 31 by the action of gravity. Unless the conveying member 31 is completely filled with the toner, the dropped toner is removed by the conveying member 31. Carried. As described above, the transport member 31 is not filled with toner because the toner transport amount is adjusted in a state where the transport space is narrowed by the drive gear 32, and the toner is not filled in the developing unit 10 and the cleaning unit 20. In consideration of the balance, the developing unit 10 reduces the amount of toner developed on the photosensitive drum, and the cleaning unit 20 drops a small amount of untransferred toner which is not transferred to the recording paper 3 as part of the toner developed on the photosensitive drum. Therefore, the transport member 31 after passing through the developing unit 10 has room for transporting the toner dropped from the cleaning unit 20. For this reason, the toner dropped in the cleaning unit 20 is reliably transported by the transport member 31.

The transport member 31 having passed through the supply window 34, the developing unit 10, and the cleaning unit 20 circulates again to the supply window 34, and the operation is repeated by supplying toner from the toner container 35 as needed.

As described above, according to the embodiment described with reference to FIGS. 1, 2 and 3 of the present invention, the toner is automatically replenished in the developing unit 20 and the cleaning unit 20 is reduced by the circulating movement of the conveying member 31. The toner collected in step (1) can be reused in the developing unit 10 with a simple mechanism.

Further, a means for narrowing the transport space is provided in the circulating transport path of the transport member 31 for circulating transport, and the toner container 35 and the transport member 31 are provided in a portion where the drive gear 32 narrows the transport space of the transport member 31. Is provided with an inclined surface 38 for generating an upward toner conveying force on a stirring member 37 for stirring the inside of the toner container 35, so that toner aggregation and clogging do not occur. An excellent toner transport mechanism can be realized.

Further, the means for narrowing the transport space is the drive gear 32 which is the drive means for the transport member 31, and the drive gear 32 for driving the transport member 31 and the agitating member 37 for agitating the inside of the toner container 35 are the same. By being driven by the rotating shaft 33, the highly reliable toner transport mechanism of the present invention can be realized in a simple mechanism with extremely high space utilization efficiency, and furthermore, a mechanism for easily transmitting power to the toner transport mechanism. Is possible.

Further, in the toner conveying mechanism of this embodiment, since the adjustment of the toner supply amount to the developing unit 10 is automatically performed, the driving of the driving shaft 33 for driving the conveying member 31 and the stirring member 37 is special. The drive of the drive shaft 33 can be driven by a driving force transmitted from the same motor as the motor for driving the image forming process, such as the photosensitive drum 1 and the developing roller 11, without requiring any simple control. An image forming apparatus having a power transmission mechanism that is extremely simple and requires no control can be realized.

Further, since the toner which decreases in the developing unit 10 is automatically supplied, the amount of toner in the storage unit 14 for storing the toner in the developing unit 10 can be reduced. The size of the image forming apparatus can be reduced, and a toner container 35 can be used to supply toner to the image forming apparatus from the outside. Various toner supply mechanisms can be realized without interference.

As the conveying member 31 used as the toner conveying means of the present invention, a circulating belt or chain or the like can be used. However, if a coil spring is used as the conveying member 31 as in this embodiment, the conventional example can be used. As described above, there is an effect that the toner can be used as a flexible chain, and the aggregation state of toner can be released by contraction or vibration of a coil spring. In particular, as shown in FIG.
Even when the toner transport mechanism including the cleaning unit 20 is housed in an integral casing, the coil spring can be extended and attached to the circulating transport path without adjusting the length of the circulating transport path using the elasticity of the coil spring. Thus, an image forming apparatus having a simple structure and easy assembly can be realized.

FIG. 4 is a view showing a coil spring used for the conveying member 31 of the embodiment shown in FIGS. 1 and 2.
4A is a sectional view of the coil spring, FIG. 4B is a side view of a part of the coil spring, p is the pitch of the coil spring, d is the diameter of the element wire of the coil spring, D is the average coil diameter, and α is the pitch angle. It is.

As the condition of the coil spring used for the conveying member 31, the wire diameter d is preferably in the range of 0.2 to 1 mm in order to obtain the necessary mechanical strength and durability without generating a large force for separating the toner. , 0.3-0.6mm
Is more preferable. Further, in order for toner to easily enter and exit from the coil spring, the gap p-d between the strands of the coil spring is preferably 1 mm or more, and more preferably 2 mm or more. Further, in order for the toner to be satisfactorily conveyed by the coil spring, the pitch p of the coil spring is preferably not more than twice, and more preferably not more than one time D + d which is the outer diameter of the coil spring. As a material of the coil spring used for the transport member 31, a metal spring is preferable because strength and durability are obtained, and generally, a material such as carbon steel such as stainless steel, a copper alloy, or a nickel alloy used for the metal spring is used. Things can be used. The coil spring in the endless state used in this embodiment can be formed by engaging hooks on both sides of a single coil spring having hooks formed at both ends, welding the coil springs at both ends, and bonding with an adhesive. Can be obtained by

FIG. 5 is a view showing the shape of the drive gear 32 used in the embodiment described with reference to FIGS. 1 and 2, FIG. 5 (a) is a top view of the drive gear 32, and FIG. FIG. 5C is a side sectional view showing an improved example of the drive gear 32, where e is the width of the tooth bottom, and β is the torsion angle of the helical gear.

As in the embodiment described with reference to FIGS. 1 and 2, the driving is performed by engaging the groove of the drive gear 32 with the wire of the coil spring using the coil spring on the conveying member 31 as described above. In addition to the effect that the conveying space of the coil spring, which is the conveying member 31, can be narrowed by engaging the teeth of the driving gear 32 into the space inside the coil spring, the conveying member 31 can be driven without slipping even in the toner. Even if there is a portion where the coil spring moves with a curvature in a portion other than the drive gear 32, a driving force that surpasses friction can be obtained, and furthermore, when the groove of the drive gear 32 and the wire of the coil spring engage. This is very preferable because irregular vibrations are given to the coil spring to improve the fluidity of the toner near the coil spring. Here, the favorable conditions of the drive gear 32 will be described with reference to FIG.

When the coil spring is driven by engaging the groove of the drive gear 32 with the element wire of the coil spring, the element wire of the coil spring enters the groove of the drive gear 32. The toner is pushed into the groove of the drive gear 32 by the wire of the coil spring. If the pushed-in toner is agglomerated and the toner aggregate increases each time the driving of the conveying member 31 is repeated, the driving gear 3
The groove 2 is gradually filled, and it becomes difficult to drive the transport member 31. The present inventors have conducted experiments and found that the driving gear 3
By increasing the root bottom width e of the coil spring larger than the diameter d of the coil wire of the coil spring, the increase of the toner aggregates in the groove of the drive gear 32 is reduced. 0.2
When the size was increased by mm, almost no increase in toner aggregates was observed. That is, the width e of the tooth bottom is preferably larger than the diameter d of the wire of the coil spring, and more preferably 0.2 mm or more than the diameter d of the wire of the coil spring. In addition to the combination other than the combination of the coil spring and the driving gear 32, it is preferable that there is a gap between the conveying unit and the driving unit where the toner interposed therebetween can move.

A driving gear 32 for driving the coil spring
Although it is possible to use a spur gear, it is possible to drive the coil spring with a spur gear by pushing the element wire of the coil spring that is inclined to the moving direction of the coil spring with the tooth surface of the vertical spur gear. As a result, a moment is given to the element wire of the coil spring, and the coil spring is easily deformed.
It is also difficult to increase the amount of engagement of the teeth of the drive gear 32 into the space inside the coil spring of the present invention. On the other hand, when the helical gear shown in FIG. 5B is used, the torsion angle β of the helical gear is set to substantially the same value as the pitch angle α of the coil spring shown in FIG. Since the moment given to the strand can be eliminated, the deformation of the coil spring can be eliminated, and the teeth of the drive gear 32 can be more easily inserted into the space inside the coil spring.

Further, the drive gear 32 for driving the coil spring has a root bottom cross section in which the depth of the root changes in the direction of the drive shaft and the center becomes deep as shown in FIG. 5C. The position of the drive gear 32 in the direction perpendicular to the drive direction of the coil spring can be regulated, and the transport member 3
The first coil spring is prevented from moving up and down and rubbing against the casing in the circulating conveyance path, so that a toner conveyance mechanism having excellent durability can be realized.

FIG. 6 is a cross-sectional view of a toner container showing toner supply of the image forming apparatus according to the embodiment of the present invention.
The image forming apparatus of the present invention can realize various toner replenishing mechanisms without interfering with the mechanism part of the image forming process. Since the image formation is performed by the member 31, toner can be supplied from a small container regardless of the width of image formation.

In FIG. 6, the toner supply container 50 has a toner supply container opening / closing lid 51 which can be slid and opened / closed to accommodate toner therein and to enter / exit the toner. The cover member 36 can be attached to and detached from the cover member 35. An engaging projection 52 for positioning the toner supply container 50 and facilitating mounting is provided on the lid member 36.
And a toner container opening / closing lid 53 that can be opened and closed by sliding to allow toner to enter and exit the toner container 35. The toner supply container of the toner supply container 50 that is positioned and mounted by the engagement projection 52 is provided. The opening / closing lid 51 and the toner container opening / closing lid 53 are simultaneously opened to supply toner from the toner supply container 50 to the toner container 35. By mounting the toner replenishing container 50 above the toner container 35, the toner can be replenished by gravity without a special mechanism.

Here, by making the amount of toner that can be stored in the toner container 35 larger than the amount of toner that is stored in the toner supply container 50, all the toner that has fallen out of the toner supply container 50 can fall into the toner container 35. Since the stirring member 37 for stirring the toner is provided in the toner container 35, all of the supplied toner can be used for image formation without forming a bridge. Further, since the toner container opening / closing lid 53 is larger than the toner supply container opening / closing lid 51, the toner can easily fall from the toner supply container 50, and the toner container
It is possible to drop to 5.

As described above, in the image forming apparatus of the present invention, toner can be supplied from a small container regardless of the width of image formation by the circulating moving conveying member 31, and a small amount of toner can be supplied to the image forming apparatus. When the toner is replenished, the toner can be replenished over the entire width of the developing unit 10 where the image is formed by the conveying member 31. In order to supply the toner little by little to the image forming apparatus by making the toner supply container 50 small, it is necessary to minimize the aggregation of the toner in the toner supply container 50 due to its own weight.
The toner can be easily stored and transported in the image forming apparatus, and the period during which the toner is stored in the image forming apparatus can be shortened. Since the supply container opening / closing lid 51 can be made smaller, there is an effect that the possibility of contaminating the surroundings with toner during toner supply operation can be minimized. The toner storage amount of the toner replenishing container 50 is preferably the minimum amount that allows continuous image output to such an extent that the user does not feel inconvenience, and preferably 5 to 50 g. Regarding the size of the toner supply container opening / closing lid 51, it is preferable that the length of the side is 40 mm or less because even when the periphery is contaminated with toner, it can be easily wiped off with a finger.

Further, in the image forming apparatus of the present invention, since the mounting portions of the toner container 35 and the toner supply container 50 can be disposed at positions away from the mechanism of the image forming process, the toner container 35 and the toner By setting the mounting portion of the supply container 50 at a position visible from the side of the image forming apparatus and forming at least a part of the toner container 35 with a transparent material, it is possible to easily confirm the toner amount. Further, a stirring member 37 for stirring the toner in the toner container 35
By providing a member for scraping off the toner on the inner wall of the toner container 35, it is possible to further easily confirm the toner amount.

[0055]

As described above, according to the present invention, it is possible to realize a toner transport mechanism which does not cause aggregation or clogging of toner. Further, the toner collected by the cleaning unit is automatically supplied to the developing unit, so that the toner can be reused.

Further, according to the present invention, not only can the toner conveying mechanism be simply realized, the amount of toner stored in the developing means can be reduced, the position of the toner replenishing means can be freely set, and the size of the toner replenishing means can be easily reduced. Therefore, it is possible to provide a small-sized image forming apparatus with a simple mechanism.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of an image forming apparatus according to the present invention.

2A is a top cross-sectional view of the toner conveying mechanism of the embodiment of FIG. 1, and FIG. 2B is a side cross-sectional view of a cross section indicated by an arrow b in FIG. 2A.

FIG. 3 is a perspective view of the stirring member of the embodiment of FIG. 1;

4A is a cross-sectional view of a coil spring that is a transport member of the embodiment of FIG. 1, and FIG. 4B is a side view of a part of the coil spring that is a transport member of the embodiment of FIG.

FIG. 5 (a) is a top view of the drive gear of the embodiment of FIG. 1,
(B) is a side view of the drive gear of the embodiment of FIG. 1, and (c) is a sectional side view showing an improvement of the drive gear of the embodiment of FIG.

FIG. 6 is a cross-sectional view illustrating toner supply of the image forming apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Photosensitive drum 2 ... Charging roller 3 ... Recording paper 4 ... Feeding roller 5 ... Transfer roller 6 ... Fixing roller 7 ... Discharge roller 10 ... Developing part 11: developing roller 12: regulating blade 13: supply roller 14: storage unit 20: cleaning unit 21: cleaning blade 31: transport member 32: drive gear 33 ··· Drive shaft 34 ··· Supply window 35 ··· Toner container 36 ··· Cover member 37 ··· Stirring member 38 ··· Inclination surface 39 ··· Lid opening and closing member 41 ··· Scanning mirror 42 ··· Scanning motor 43 Lens 44 Mirror 50 Toner supply container 51 Toner supply container opening / closing lid 52 Engagement projection 53 Toner container opening / closing lid

Continuation of the front page (56) References JP-A-63-246780 (JP, A) JP-A-55-45012 (JP, A) JP-A-58-184969 (JP, A) JP-A-58-102269 (JP) JP-A-4-1611971 (JP, A) JP-A-4-125670 (JP, A) JP-A-3-89281 (JP, A) JP-A-3-112762 (JP, U) 49-16749 (JP, Y1) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 21/10-21/12 G03G 15/08-15/08 507

Claims (2)

(57) [Claims] 1. A developing means for developing a latent image formed by exposing a photoreceptor to develop a latent image, and a toner container for storing toner for replenishing the toner consumed by the developing means. An image forming apparatus including a developing unit and a toner conveying unit that circulates and moves in communication with the toner container, wherein a stirring shaft that stirs the toner inside the toner container and a rotation shaft of a driving unit that drives the toner conveying unit; An image forming apparatus, wherein the rotation axes of the units are the same. 2. An image forming apparatus according to claim 1, wherein said stirring means for stirring the toner in said toner container has means for generating an upward toner conveying force.