JP2002040770A - Toner cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner cartridge that can efficiently eject toner. SOLUTION: In the toner cartridge storing the toner for an image forming device utilizing an electrophotographic method, a case main body storing the toner, a toner agitating shaft supported by the case main body to be freely revolved and a fin that is extended from the toner agitating shaft and agitating the toner are provided. The revolution of the toner agitating shaft is stopped when the quantity of the toner becomes less than a specified quantity.

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 such as a copying machine, a printer, a facsimile and the like using an electrophotographic method, and more particularly to a toner cartridge for supplying toner to a developing device.

[0002]

2. Description of the Related Art An image forming apparatus of the above-mentioned type comprises an image carrier such as a photoconductor which is driven to rotate, a latent image forming means for sequentially forming an electrostatic latent image on the photoconductor, and an electrostatic latent image. The image forming apparatus includes a developing unit that develops a toner image and a transfer device that transfers a plurality of color toner images on a photoconductor to a recording medium.

Conventionally, the above-mentioned developing device includes a developing device having a developing roller in contact with a photoreceptor and a toner cartridge detachably mounted on the developing device and supplying toner to the developing device. For example, 3-53
As shown in FIG. 1A, a rotating shaft 100 rotatably supported in a cylindrical toner cartridge 110 and a rotating shaft 100 fixed on the rotating shaft and mounted near a toner discharge port 102, as shown in FIG. Raised plate 10 for discharging toner inside
4 and a spiral scraping plate 106 which is also fixed to a portion other than the scraping plate 104 on the rotating shaft and which transfers the toner near both ends of the toner cartridge in the axial direction toward the toner discharge port 102. Has proposed a toner cartridge having a different structure. In the toner cartridge having this structure, it is possible to increase the size of the toner cartridge as much as possible regardless of the size of the toner outlet, increase the amount of stored toner, and reduce the frequency of replacement.

[0004]

In the case of a cylindrical toner cartridge as shown in FIG. 1A, when increasing the amount of stored toner, the volume is increased by increasing the radius of the cylinder. Therefore, when the toner cartridge is mounted on the image forming apparatus, the size of the toner cartridge is limited depending on the shape of the place where the toner cartridge is mounted.

On the other hand, if the size of the toner cartridge itself is reduced, the problem of the mounting place inside the image forming apparatus can be solved. However, since the amount of stored toner decreases, the number of times of replacement of the toner cartridge increases and the maintenance becomes complicated. Another problem arises. Therefore, when a conventional cylindrical cartridge is used in a full-color image forming apparatus,
There is a problem that the size of the apparatus cannot be reduced without reducing the amount of stored toner.

On the other hand, in the conventional toner cartridge shown in FIG. 1 (A), both the scraping plate 104 and the scraping plate 106 are rotated by one rotating shaft 100 to stir the toner. As shown in FIG. 1 (B), the degree of compression between the toner particles is low, and the rotational torque is large.

In order to smoothly supply a fixed amount of toner to the developing device from the outlet of the toner cartridge, it is necessary that the toner is appropriately compacted near the toner outlet. However, if the consolidation is too high, the toner solidifies in the vicinity of the toner outlet, and a stable constant amount of toner cannot be supplied.

Further, in the conventional toner cartridge shown in FIG. 1A, the toner is excessively stirred, and the contact area between the toner and the air tends to increase.
For this reason, as shown in FIG. 1C, the toner locally solidifies due to adsorption by water molecules in the air. Therefore, there is a problem in that the toner discharge amount varies, and a stable toner discharge amount cannot be obtained.

In order to realize a stable and constant toner discharge amount, it is preferable that the toner is not locally solidified in the toner cartridge, but is uniformly dispersed in the toner components and is appropriately compacted near the toner discharge port. Therefore, the toner needs both “appropriate loosening” by some transport member and “appropriate compaction” near the toner discharge port. As described above, in the toner cartridge, the toner is required to have two contradictory states of “appropriate loosening” and “appropriate compaction”.

The present invention has been made to solve the above problems. That is, the first object of the present invention is to
An object of the present invention is to provide a toner cartridge capable of obtaining a stable toner discharge amount by adopting a configuration in which toner is compressed and conveyed to a toner discharge port.

Another object of the present invention is to provide a toner cartridge which is not affected by water particles in the air and solidifies the toner.

Still another object of the present invention is to provide a toner cartridge which reduces a driving torque of a rotating member for realizing a smooth flow of toner in the toner cartridge.

Accordingly, an object of the present invention is to provide a toner cartridge which can solve the above-mentioned problems. This object is achieved by a combination of features described in the independent claims. The dependent claims define further advantageous embodiments of the present invention.

[0014]

According to a first aspect of the present invention, there is provided a toner cartridge containing a toner for an image forming apparatus utilizing electrophotography, wherein a case body containing the toner is provided. And a toner stirring device rotatable with respect to the case body. The rotation of the toner stirring shaft is stopped when the toner amount is equal to or less than a predetermined amount.

The toner stirring device may stop rotating when the amount of the toner falls below a predetermined amount and the rotational torque proportional to the amount of the toner contained in the case body is lost.

When the amount of the toner becomes equal to or less than a predetermined amount and there is no toner for pressing the toner stirring device downward,
The rotation of the toner stirring device may be stopped.

[0017] The image forming apparatus may further include a transmission unit for transmitting a driving force for rotating the toner stirring device to the toner stirring device. The transmission unit may stop transmitting the driving force to the toner stirring device when the amount of the toner falls below a predetermined amount.

[0018] The transmission portion may be detachably provided to the toner stirring device, and may transmit the driving force to the toner stirring device according to the attachment or detachment. When the amount of the toner becomes equal to or less than a predetermined amount, the transmission unit may be separated from the stirring device.

The transmission may be a gear, and the transmission may be a clutch.

The stirring device is rotatably held by the case main body and stirs a first stirring shaft for stirring the toner.
A first stirring fin extending from the first stirring shaft; a second stirring shaft rotatably held by the case main body and stirring the toner conveyed by the first stirring shaft; A second stirring fin extending from the stirring shaft. At least one of the first and second stirring shafts may stop rotating when the amount of the toner becomes equal to or less than a predetermined amount.

The rotation of the first stirring fin may be stopped when the amount of toner to be conveyed in the direction of the second stirring fin becomes less than a predetermined amount.

Note that the above summary of the present invention does not list all of the necessary features of the present invention, and sub-combinations of these features may also constitute the present invention.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described through embodiments of the present invention. However, the following embodiments do not limit the claimed invention and have the features described in the embodiments. Not all combinations are essential to the solution of the invention.

FIG. 2 is a schematic sectional view of the toner cartridge 20 and an image forming apparatus in which the toner cartridge 20 is mounted. This image forming apparatus is a color electrophotographic printer capable of forming a full-color image with four color toners.
The present invention is not limited to this, and is applicable to all image forming apparatuses of a type that forms a toner image on an image carrier such as a photoconductor.

The configuration and operation of the image forming apparatus will be described with reference to FIG. The image forming apparatus includes a photoconductor 1, a charging roller 2, an exposure unit 3, a developing unit 4, an intermediate transfer device 5, and a photoconductor cleaning device 6. The charging roller 2, the exposure unit 3, the developing unit 4, the intermediate transfer device 5, and the photoconductor cleaning device 6 are arranged around the photoconductor 1. Further, the toner cartridge 20 is mounted on the developing unit 4. The charging roller 2 charges the photoconductor 1, and the exposure unit 3 forms an electrostatic latent image on the photoconductor 1. The developing unit 4 develops the electrostatic latent image. The intermediate transfer device 5 transfers the toner image formed on the photoconductor 1 onto the sheet S.

The photoreceptor 1 has a thin cylindrical conductive substrate and a photosensitive layer formed on the surface thereof, and is driven to rotate in a direction indicated by an arrow by a driving means (not shown).

The developing unit 4 includes a developing unit 4 for yellow.
Y, a developing device 4C for cyan, a developing device 4M for magenta, and a developing device 4K for black. Each developing device includes a developing roller 4b provided in a developing housing 4a. These developing units 4Y, 4C, 4M, and 4K are swingable, come in contact with and separate from the photosensitive member 1, and selectively rotate with the developing roller 4b of one developing unit for each rotation of the photosensitive member 1. Only the photosensitive member 1 comes into contact with the photosensitive member 1.

The intermediate transfer device 5 includes an intermediate transfer belt 7, a driving roller 9 for running the intermediate transfer belt 7, a transfer portion T1 for transferring the toner image formed on the photosensitive member 1 to the intermediate transfer belt 7, and a primary transfer portion T1. Transfer backup roller 10,
It has a secondary transfer backup roller 11 and the like, and an endless intermediate transfer belt 7 is stretched around these rollers. In the primary transfer section T1, the intermediate transfer belt 7
It is urged toward the photoconductor 1 by the primary transfer backup roller 10. In the secondary transfer portion T2, the secondary transfer backup roller 11 and the secondary transfer roller 12 are arranged at opposing positions with the intermediate transfer belt 7 interposed.

Next, the operation of the image forming apparatus will be described. When an image forming signal is input from a computer (not shown), the photosensitive member 1, the developing rollers 4b of the developing unit 4, and the intermediate transfer belt 7 are driven to rotate. First, the outer peripheral surface of the photoreceptor 1 is uniformly charged by the charging roller 2, and the outer peripheral surface of the uniformly charged photoreceptor 1 is exposed to the first color (for example, yellow) image information by the exposure unit 3. The selective exposure L is performed, and a yellow electrostatic latent image is formed.

Only the developing roller 4b of the yellow developing unit 4Y comes into contact with the photoreceptor 1, whereby a toner image of a yellow electrostatic latent image is formed on the photoreceptor 1. A primary transfer voltage having a polarity opposite to the chargeability of the toner is applied to the intermediate transfer belt 7, and the toner image formed on the photoconductor 1 is transferred onto the intermediate transfer belt 7 in the primary transfer portion T1. After the toner remaining on the photoreceptor 1 is removed by the photoreceptor cleaning device 6, the outer peripheral surface of the photoreceptor 1 is discharged by a discharger (not shown).

The above operation is performed, for example, in the case of the second image forming signal.
One of the photoconductor 1 and the intermediate transfer belt 7 corresponding to the color (cyan), the third color (magenta), and the fourth color (black).
The formation and development of the latent image by rotation are repeated, and the toner images of four colors according to the content of the image forming signal are superimposed and transferred on the intermediate transfer belt 7. Then, at the timing when this full-color image reaches the secondary transfer portion T2, the sheet S is supplied from the direction of the arrow to the secondary transfer portion T2, and at this time, the transfer roller 12 is pressed against the intermediate transfer belt 7 and the secondary transfer is performed. A voltage is applied, and the full-color toner image on the intermediate transfer belt 7 is transferred onto the recording medium S. Although the first color (yellow), the second color (cyan), the third color (magenta), and the fourth color (black) are used in the above-described processing of the image forming signal, the processing order is not limited to this. Not something.

The toner cartridge 20 is detachably mounted on the developing housing 4a of the developing device 4Y. When the four toner cartridges 20 are mounted on the developing unit 4, the four toner cartridges 20 are arranged substantially radially around the photoconductor 1. The case main body 22 of the toner cartridge 20 is provided in a cylindrical shape having a cross section having the shape shown in FIG. The case body 22 has a toner outlet 24 and a projection 26. The inside of the case body 22 is divided into two toner storage chambers 90 and 92 with the protrusion 26 as a boundary. First
The toner storage chamber 90 is located in a region away from the toner outlet 24, and the second toner storage chamber 92 is located in the toner outlet 2
4 is provided in the region on the side having 4. The first toner storage chamber 90 and the second toner storage chamber 92 are both provided in a substantially cylindrical shape, and the inside of the case body 22 is
It has a glasses-shaped cross section.

The second toner storage chamber 92 is provided such that the cross-sectional area of the cross section shown in the figure is smaller than the cross-sectional area of the first toner storage chamber 90 shown in the figure. The second toner storage chamber 92 is occupied by another member when mounted on the developing unit 4. Therefore, the space occupied by the second toner storage chamber 92 is limited. On the other hand, since the first toner storage chamber 90 is disposed at a position away from the developing unit 4, the first toner storage chamber 9
The cross-sectional area can be designed to be larger than that of zero.
Thus, the case main body 22 is connected to the first toner storage chamber 9.
Since it is composed of the 0 and the second toner storage chambers 92, even when it is mounted in the crowded developing unit 4, the space can be effectively used and more toner can be stored. Also, since there is no restriction by the surrounding members, the second
Can be further enlarged. Therefore, the toner cartridge 20 capable of storing more toner can be mounted.

A toner outlet 24 for discharging toner to the developing unit 4 is formed in the case body 22.
The toner outlet 24 is configured such that when the toner cartridge 20 is mounted on the developing housing 4a, toner is supplied from the toner outlet 24 to the toner inlet 4c of the developing housing 4a. The other developing units 4C, 4C
Similarly, the toner cartridge 20 is detachably attached to M and 4K. Regarding the toner cartridge 20,
It will be described in detail in FIG.

FIG. 3A shows a cross section taken along line AA of the toner cartridge 20 of FIG. FIG. 3B is a diagram of a cross section of the toner cartridge 20 taken along line CC of FIG.

The solid line shown inside the case main body 22 in FIG. The protrusion 26 divides the space inside the case main body 22 into a first toner storage chamber 90 and a second toner storage chamber 92. That is, the case main body 22 has two chambers in which the first toner storage chamber 90 and the second toner storage chamber 92 communicate with each other.

A toner stirring member 40 and a toner conveying member 60 are provided in each of the first toner storage chamber 90 and the second toner storage chamber 92. First toner storage chamber 90
Has a toner stirring member 40 and a bearing portion 28a that rotatably holds the toner stirring member 40. The second toner accommodating chamber 92 includes the toner conveying member 60 and the toner conveying member 6.
And a toner discharge port 2 for discharging toner toward the developing device unit 4.
4

The toner stirring member 40 includes an upstream rotating shaft 42 rotatably supported by the case body 22 and first, second, and third stirring fins 44, 4 extending from the upstream rotating shaft 42.
5 and 46, and two end fins 56 and 57 provided at the end of the drive unit side and the end of the supply port for supplying toner on the cap side, respectively. The stirring fins 44, 45, 46 and the end fins 56, 57 are provided in a plate shape. The first, second, and third stirring fins 44, 45, 46
Each extends from the upstream rotation shaft 42 in directions different from each other by 180 degrees. The stirring fins 44, 45, 46 and the end fins 56, 57 rotate together with the upstream rotation shaft 42.

Each of the stirring fins 44, 45, and 46 has a two-piece structure having cuts, and the outer fin is easily bent and the inner fin is not easily bent. It is preferable that the degree of flexibility of each fin is set to such a degree that the fins are appropriately bent when the toner is carried and the load of the toner is dispersed.

The upstream rotating shaft 42 is driven by a driven first gear 320
And the driven first gear 320 is engaged with the drive gear 324. One end of the upstream rotation shaft 42 is supported by the bearing 28 a and is provided in a cantilever shape. One end of the upstream rotation shaft 42 integrated with the driven first gear 320 moves. By this movement, the driven first gear 320 and the drive gear 324 are engaged or disengaged.

The toner conveying member 60 has a downstream rotating shaft 62 rotatably supported by the case body 22, a plurality of arc blades 64 extending from the downstream rotating shaft 62, and two scraping fins 68. The plurality of arc blades 64 extend from the downstream rotation shaft 62 at predetermined intervals in the axial direction 200 of the downstream rotation shaft 62. The scraping fin 68 is provided at a position corresponding to the toner discharge port 24 on the toner transport shaft 64.

The downstream rotating shaft 62 is driven by a second driven gear 322.
And the driven second gear 322 is engaged with the drive gear 324. The drive gear 324 is connected to a drive unit (not shown), and is connected to the upstream rotation shaft 42 and the downstream rotation shaft 6.
2 rotates by the driving force of the driving unit.

The first, second, and third stirring fins 44, 45,
Reference numeral 46 denotes a position of the arc blade 68 of the toner conveying member 60 on the upstream rotation shaft 42,
8 and a position corresponding to the position of the scraping fin 68. The longitudinal directions of the upstream rotation shaft 42, the downstream rotation shaft 62, and the cylinder are substantially parallel.

The case body 22 is provided in a cylindrical shape. The cross section perpendicular to the longitudinal direction of the cylinder of the case body 22 is shown in FIG.
It is a glasses shape having two circles as shown in FIG. A projection 26 extending in the longitudinal direction between the first toner storage chamber 90 and the second toner storage chamber 92 is provided on the lower inner wall of the case main body 22.

The arc blade 64 and the scraping fin 68
It rotates together with the downstream rotation shaft 62. Upstream rotation shaft 42
The downstream rotation shaft 62 rotates counterclockwise 210 when viewed in the axial direction 200.

Next, the flow of toner inside the toner cartridge 20 realized by the above members will be described.

FIG. 4 schematically shows the flow of toner inside the toner cartridge 20. FIG. 4A shows a cross section of the toner cartridge 20 of FIG. 2 along the line BB. FIG. 4B is a cross-sectional view of the toner cartridge 20 taken along the line DD in FIG.

As shown in FIG. 4A, the toner stored in the first toner storage chamber 90 is supplied to the stirring fins 44 and 4.
The toner is conveyed in the direction perpendicular to the axial direction 200 by the transfer rollers 5 and 46 and moves to the second toner storage chamber 92. FIG. 4 (B)
Indicates the flow of toner at this time. As shown in the figure, the toner stored in the second toner storage chamber 92 is conveyed in the rotation direction 210 by turning counterclockwise when viewed in the axial direction 200 of the upstream rotation shaft 42. The toner transported to the bottom 90 a side of the first toner storage chamber 90 gets over the protrusion 26 and is transported to the second toner storage chamber 92. Thus, the toner stored in the first toner storage chamber 90 is conveyed to the second toner storage chamber 92 by the rotation of the upstream rotation shaft 42.

Next, the flow of toner in the second toner storage chamber 92 will be described. As shown in FIG. 4 (A), the arcuate blades 64 extending from both ends of the downstream rotation shaft 62 allow
The toner accommodated in both ends of the second toner accommodating chamber 92 is conveyed in the axial direction 200 of the downstream rotary shaft 62 and the direction opposite to the axial direction 200 while rotating around the downstream rotary shaft 62. You. That is, the toner is conveyed toward the toner outlet 24. A scraping fin 68 extends from the downstream rotation shaft 62 corresponding to the vicinity of the toner discharge port 24. As shown in FIG. 4A, the toner conveyed to the vicinity of the toner discharge port 24 is moved by the scraping fins 68 in the axial direction
It is transported in a direction perpendicular to 0. The toner stored in the case body 22 in the above flow is discharged from the toner discharge port 24.

The case body 22 is provided with the toner discharge port 2.
The developing unit 4 is attached to the developing unit 4 with the lower side 4 facing downward. Therefore, the toner accommodated in the vicinity of the toner discharge port 24 can maintain an appropriate compaction state due to the weight of the toner itself.

Since the projection 26 is provided between the first toner storage chamber 90 and the second toner storage chamber 92, the toner stored in the first toner storage chamber 90 can be transferred to the second toner storage chamber. 92 can be prevented. Therefore, even when the consumption of toner progresses and the amount of toner stored in the case main body 22 decreases, the remaining toner can be reliably conveyed to the toner outlet 24. In this way, the toner stored in the case body 22 can be used efficiently and without waste until the end. In addition, since the protrusion 26 is set at an appropriate height, it is possible to prevent the toner from being excessively conveyed from the second toner storage chamber 92 to the first toner storage chamber 90.

FIG. 5C shows the interior of the toner cartridge 20 when the amount of toner further decreases and the amount of toner stored in the first toner storage chamber 90 decreases to a position lower than the height of the upstream stirring shaft 42. Show. At this time, most of the toner transported to the second toner storage chamber 92 is hindered by the protrusion 26 provided between the first toner storage chamber 90 and the second toner storage chamber 92, so that the first toner Does not return to the toner storage chamber 90. Therefore, the amount of toner stored in the first toner storage chamber 90 decreases first. First toner storage chamber 9
0, the amount of toner stored in the upstream stirring shaft 42 decreases.
Stops, and the toner transport shaft 62 transports the toner stored in the second toner storage chamber 92 toward the toner outlet 24.

When the toner of the degree shown in FIGS. 5A and 5B is stored in the toner cartridge 20,
The upstream rotation shaft 42 provided in a cantilever shape is bent toward the bottom 90a due to the weight of the toner. At this time, the driven first gear 320 and the drive gear 324 provided integrally with the upstream rotation shaft 42 are engaged. That is, the upstream rotation shaft 42 is rotated by the driving force of the driving unit, and conveys the toner toward the second toner storage chamber 92. When the amount of toner in the first toner storage chamber 90 decreases and the state shown in FIG. 5C is reached, the upstream rotation shaft 42 is released from the weight of the toner, and returns to its original state by the self-restoring force. At this time, the engagement between the driven first gear 320 and the drive gear 324 is released.
That is, the rotation of the upstream rotation shaft 42 stops. As described above, when the toner amount becomes equal to or less than the predetermined amount, the upstream rotation shaft 42 stops rotating. In the present embodiment, as shown in FIG. 5C, the amount of toner is
When the level reaches a level lower than 2, the upstream rotation shaft 42 stops rotating. 6 and thereafter, the operation of the toner cartridge 20 at this time will be described in detail.

FIG. 6 shows the mechanism and operation of stopping the rotation of the upstream stirring shaft 42. This figure is a view of a side surface on the side having the first driven gear 320 and the second driven gear 322 from the outside of the case body 22. The upstream stirring shaft 42 is provided integrally with the driven first gear 320. The downstream rotation shaft 62 is provided integrally with the driven second gear 322. The driven first gear 320 and the driven second gear 322 are engaged with the driving gear 324. The drive gear 324 is connected to a drive unit (not shown). The driving gear 324 is rotated by a driving force applied from a driving unit.

The case main body 22 has a substantially elliptical through hole 300 through which the upstream stirring shaft 42 penetrates. The upstream stirring shaft 42 is disposed in the longitudinal direction of the through-hole 300,
The through hole 300 is movably held between the end 300a and the through hole second end 300b. The through hole 300 is provided in a state where the major axis of the ellipse is inclined toward the drive gear 324. When the driven first gear 320 is located at the through hole first end 300a, the driven first gear 320
And the drive gear 324 are provided at a position and size that can be engaged.

FIG. 6A shows the driven first gear 32 when the driven first gear 320 and the driving gear 324 are engaged.
0, the driven second gear 322 and the drive gear 324 are shown.
When the toner of the degree shown in FIGS. 5A and 5B is contained in the toner cartridge 20, as shown in FIG. 6A, the driven first gear 320 and the drive gear 324 are used.
Engage. Thus, when the upstream stirring shaft 42 is located at the first end 300a of the through hole, the driven first gear 320
And the drive gear 324 are engaged. Therefore, the driven first gear 320 and the driven second gear 322 are driven by the driving gear 324. That is, the upstream stirring shaft 42 and the toner conveying shaft 62 are rotated by the driving force of the driving unit.

FIG. 6B shows the driven first gear 320, the driven second gear 322, and the driving gear 324 when the driven first gear 320 and the driving gear 324 are disengaged. As shown in FIG. 5C, the toner is
6, the upstream rotation shaft 42 moves to the second end 300b of the through hole, and the driven first gear 320 and the drive gear 324 are disengaged as shown in FIG. I do. Thus, when the upstream stirring shaft 42 is positioned at the second end 300b of the through hole, the driven first gear 320 and the drive gear 324 are not engaged. Therefore, the upstream rotation shaft 42 does not rotate. That is, only the toner conveying shaft 62 is rotated by the driving force of the driving unit, and the upstream stirring shaft 42 is rotated.
Stops. As described above, since the driven first gear 320 is provided so as to be able to move through the through-hole 300, the driven first gear 320 is provided.
Gear 320 and drive gear 324 can be engaged or disengaged.

FIG. 7 shows the driven first gear 320 and the driven second gear 322 shown in FIG. FIG. 7A shows the driven first gear 320 and the drive gear 324 when the upstream stirring shaft 42 is located at the first end 300a of the through hole. At this time,
The driven first gear 320 and the drive gear 324 are engaged. FIG. 7B shows that the driven first gear 320 is
24 shows the driven first gear 320 and the driving gear 324 when stopping on the side opposite to the side 24. At this time, the driven first gear 320
And the drive gear 324 does not engage. As described above, the upstream stirring shaft 42 is connected to the through-hole first end 300a and the through-hole second end 3a.
00b, the driven first gear 320
And the drive gear 324 can engage and disengage.

A pad 302 is provided at a position corresponding to the inside of the case main body 22 of the upstream stirring shaft 42. The pad 302 moves together with the upstream stirring shaft 42 while being in contact with the case main body 22. Therefore, when the upstream stirring shaft 42 moves through the through hole 300, it is possible to prevent toner from leaking from between the through hole 300 and the upstream stirring shaft 42.

As described above, the first toner storage chamber 90
When the amount of toner decreases, the rotation of the upstream stirring shaft 42 can be stopped. Therefore, the drive unit is provided with the upstream stirring shaft 4.
It is not necessary to supply the driving force required for the 2 to rotate.
When the amount of toner decreases, the upstream stirring shaft 42 stops rotating, so that the side flexible fins 45 and 46 and the center flexible fin 44 tip contact the inside of the case body 22. Wear can be avoided.

Next, the mechanism by which the first driven gear 320 and the drive gear 324 described with reference to FIGS. 6 and 7 engage and disengage from each other will be described in detail.

FIGS. 8A and 8B show the entire first toner storage chamber 90 corresponding to FIGS. 7A and 7B, respectively. The upstream stirring shaft 42 has an end opposite to the end of the upstream stirring shaft 42 shown in FIG.
fixed to a. Thereby, the upstream rotation shaft 42 is
It is supported in a cantilever shape. The upstream rotation shaft 42 is rotatably supported by the bearing 28a, and is provided so as to abut the second end 300b of the through hole as shown in FIG. 8B.

FIGS. 8A and 8B show FIGS. 5A and 5B, respectively.
Shows the first toner storage chamber 90 when the toner of the degree shown in FIG. The upstream stirring shaft 42 is pressed toward the bottom 90a by the weight of the toner. Thereby, the upstream stirring shaft 42 is bent, and the end of the upstream rotation shaft 42 contacts the first end 300a of the through hole.

FIG. 8 (B) shows, as shown in FIG.
The first toner storage chamber 90 when the amount of toner has decreased to a level below the upstream rotation shaft 42 is shown. When the amount of toner decreases, the upstream stirring shaft 42 returns from the state of being bent due to the weight of the toner. At this time, the upstream rotation shaft 4
2 moves by self-healing force, and the through-hole second end 300
b. As described above, since the upstream stirring shaft 42 is supported in a cantilever shape, the first driven gear 320 and the driving gear 324 can be engaged and disengaged using the weight of the toner. it can.

FIG. 9 shows another embodiment for realizing the engagement and disengagement of the driven first gear 320 and the driving gear 324. In this figure, a toner receiving cylinder 340 is further provided on the cantilever-shaped upstream stirring shaft 42 described in FIG. The toner receiving cylinder 340 is a hollow and substantially cylindrical, and has a conveying member 44 that protrudes in a spiral shape inside.
The toner receiving cylinder 340 is fixed to the upstream stirring shaft 42,
It rotates coaxially with the upstream rotation shaft 42. Toner receiving cylinder 340
A projection 342 is provided at the center position of.

When the toner has entered the toner receiving cylinder 340, the toner receiving cylinder 340 is pressed toward the bottom 90a by the weight of the entered toner, and the upstream stirring shaft 42 moves toward the bottom 90a. At this time, the toner that has entered the inside of the toner receiving cylinder 340 is conveyed in the axial direction 200 by the spiral conveying member 344 provided inside the toner receiving cylinder 340, and
Is discharged from

The toner that has entered the inside of the toner receiving cylinder 340 moves the upstream stirring shaft 42 to the bottom 9 by the weight of the toner.
While pressing to the 0a side, the upstream rotation shaft 42 contacts the through hole first end 300a. At this time, the driven first gear 3
20 and drive gear 324 are engaged. That is, the upstream stirring shaft 42 rotates. On the other hand, when the toner is consumed and decreased, the level of the toner is decreased.
2 is released from the pressing of the toner,
Abuts on the second end 300b of the through hole. At this time, the engagement between the driven first gear 320 and the drive gear 324 is released. That is, the rotation of the upstream stirring shaft 42 stops.

As described above, by providing the toner receiving cylinder 340, the upstream stirring shaft 42 can be rotated until the toner decreases to a level below the upstream stirring shaft 42. Therefore, the amount of remaining toner can be reduced. Further, since the protrusion 342 is provided at the center of the toner receiving cylinder 340 in this way, when the upstream stirring shaft 42 is pressed, the toner located below the toner receiving cylinder 340 is released to the periphery. Therefore, it can be moved to the bottom 90a side.

Although the present invention has been described with reference to the embodiment, the technical scope of the present invention is not limited to the scope described in the above embodiment. Various changes or improvements can be added to the above embodiment. It should be noted that such modified or improved embodiments may be included in the technical scope of the present invention.
It is clear from the description of the claims.

As a first modified example, in this embodiment, the operation of stopping only the upstream stirring shaft 42 by the engagement and disengagement of the gear has been described with reference to FIGS. 6 and 7. A clutch mechanism may be provided instead of the gear. Also in this case, the upstream stirring shaft 42 is
The first clutch 320 corresponding to the driven first gear 320 and the third clutch corresponding to the driving gear 324 are movably held between the through hole first end 300a and the through hole second end 300b. The disengagement of the engagement causes the upstream stirring shaft 4
The operation of stopping only 2 may be realized.

In the above-described embodiment, the reduction of the toner is recognized by using the cantilever-shaped upstream rotation shaft 42. However, as a second modified example, the developing unit 4 May recognize the amount of toner reduction based on the amount of toner attached to the photoconductor 1. Specifically, when an image forming signal is input from a computer (not shown), the amount of toner required to form the input image is calculated, and the data is stored in a memory or the like. In this manner, the toner cartridge 20
Recognize the amount of decrease in the amount of toner stored in the printer. Since the amount of toner required to draw a certain character is almost constant,
The consumed toner amount can be estimated based on the input image forming signal. When the toner cartridge 20 is replaced, the amount of toner stored in a memory or the like is reset, and the amount of toner reduction is estimated based on the subsequent input of an image forming signal. When the toner has decreased to a predetermined amount, the computer gives an instruction to disengage the driven first gear 320 and the drive gear 324.

As a third modification, an optical sensor may be used as means for recognizing the toner reduction amount. The case body 22 is formed of a transparent or translucent material, and an optical sensor is provided, for example, near the through hole 300. by this,
The amount of toner reduction may be recognized from a change in optical reflection or transmission.

As a fourth modification, a piezoelectric sensor may be used as means for recognizing the amount of toner reduction. For example, a piezoelectric sensor may be provided near the through hole 300. Measure the change in acoustic impedance that changes according to the amount of toner,
From the result, a phenomenon value of a certain amount of toner may be detected.

[0074]

As is apparent from the above description, according to the present invention, the torque at the time of stirring the toner can be reduced, and the wear of the flexible fin can be prevented.

[Brief description of the drawings]

FIG. 1 is a view showing a toner cartridge according to a conventional example.

FIG. 2 is a schematic sectional view of the toner cartridge 20 and an image forming apparatus in which the toner cartridge is mounted.

FIG. 3 is a cross-sectional view of the toner cartridge 20.

FIG. 4 is a diagram schematically illustrating a flow of toner inside a toner cartridge.

FIG. 5 is a diagram showing the inside of the toner cartridge 20 when the toner contained in the toner cartridge 20 is supplied to the developing unit 4;

FIG. 6 is a diagram illustrating a configuration and an operation in which the upstream stirring shaft stops rotating.

FIG. 7 is a diagram showing a driven first gear 320 and a driven second gear 322 shown in FIG. 6;

FIG. 8 is a diagram showing engagement and disengagement of a driven first gear 320 and a driving gear 324.

FIG. 9 is a diagram showing another embodiment for realizing engagement and disengagement of the driven first gear 320 and the driving gear 324.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor 2 charging roller 3 exposure unit 4 developing unit 5 intermediate transfer device T1 primary transfer unit T2 secondary transfer unit 20 toner cartridge 22 case body 24 toner discharge port 26 projection unit 28 bearing unit 33 toner supply port 34 cap 36 drive Unit 40 Toner stirring member 42 Upstream rotation shaft 44 First stirring fin 45 Second stirring fin 46 Third stirring fin 47 First stirring piece 48 Second stirring piece 56, 57 End fin 60 Toner transport member 62 Downstream rotation shaft 64 arc blade 68 scraping fin 90 first toner storage chamber 92 second toner storage chamber 300 through hole 302 pad 320 driven first gear 322 driven second gear 324 drive gear 340 toner receiving cylinder

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroaki Kamada 3-5-5 Yamato, Suwa-shi, Nagano Seiko Epson Corporation (72) Inventor Hiroyuki Maruyama 3-5-35 Yamato, Suwa-shi, Nagano Seiko-Epson F term (reference) 2H077 AA02 AB02 AB03 AB14 AB15 AB18 AC02 AC03 AD06 BA02 BA08 DA15 DB14 DB21

Claims (9)

[Claims] 1. A toner cartridge containing toner for an image forming apparatus using electrophotography, comprising: a case main body containing the toner; and a toner stirring device rotatable with respect to the case main body. The toner cartridge according to claim 1, wherein the toner stirring device stops rotating when the toner amount is equal to or less than a predetermined amount. 2. The toner stirring device stops rotating when the amount of the toner becomes equal to or less than a predetermined amount and the rotational torque proportional to the amount of the toner contained in the case body is lost. The toner cartridge according to claim 1, wherein: 3. The toner stirring device according to claim 1, wherein the rotation of the toner stirring device is stopped when the amount of the toner becomes equal to or less than a predetermined amount and there is no toner pressing the toner stirring device downward. The toner cartridge as described in the above. 4. A transmission unit for transmitting a driving force for rotating the toner stirring device to the toner stirring device, wherein when the amount of the toner becomes equal to or less than a predetermined amount, the transmission unit transmits the driving force to the toner stirring device. 4. The toner cartridge according to claim 1, wherein transmission of the driving force is stopped. 5. The transmission unit is detachably provided to the toner stirring device, and transmits the driving force to the toner stirring shaft in accordance with the attachment / detachment, and when the toner becomes a predetermined amount or less, the transmission unit. The toner cartridge according to claim 4, wherein the cartridge is detached from the toner stirring device. 6. The toner cartridge according to claim 5, wherein said transmission portion is a gear. 7. The toner cartridge according to claim 5, wherein the transmission unit is a clutch. 8. The toner stirring device includes a first toner stirring shaft rotatably held by the case main body and stirring the toner, and a first stirring fin extending from the first toner stirring shaft. A second toner stirring shaft rotatably held by the case main body and stirring the toner conveyed by the first toner stirring shaft; and a second stirring fin extending from the second toner stirring shaft. The toner according to any one of claims 1 to 7, wherein at least one of the first and second toner stirring shafts stops rotating when the amount of the toner becomes equal to or less than a predetermined amount. cartridge. 9. The apparatus according to claim 8, wherein the first stirring fin stops rotating when the amount of toner to be conveyed in the direction of the second stirring fin becomes less than a predetermined amount. Toner cartridge.