Patent Application
20190121258
This application is based upon and claims the benefit of priority from the corresponding Japanese Patent Application No. 2017-203376 filed on Oct. 20, 2017, the entire contents of which are incorporated herein by reference.
The present disclosure relates to a toner container having a mechanism for feeding toner from a container body, and an image forming apparatus including the toner container.
Generally, an electrophotographic image forming apparatus includes a removably attached toner container. The toner container may be also referred to as a toner box.
The toner container includes a container body for storing toner, and a screw feeder for feeding the toner from the container body. The toner fed from the container body is supplied to a developing device.
In addition, according to a known technology, toner inside the container body of the toner container is conveyed to the developing device by an air flow or a powder pump.
A toner container according to an embodiment of the present disclosure includes a container body, a tubular body, and a screw feeder. The container body stores toner. The tubular body forms a toner conveyance path communicating with an inside of the container body. The screw feeder includes a shaft and a blade, wherein the shaft is formed extending from inside the container body toward an entrance of the toner conveyance path, and the blade is formed protruding spirally from the shaft. The screw feeder feeds the toner in the container body to the toner conveyance path by being rotationally driven inside the container body, and pushes the toner that has arrived inside the toner conveyance path further along the toner conveyance path by feeding pressure of succeeding toner.
An image forming apparatus according to another embodiment of the present disclosure includes a developing device and the toner container. The developing device develops an electrostatic latent image on a photoconductor into a toner image. The toner container is removably attached to a body housing the developing device, and supplies toner to the developing device.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description with reference where appropriate to the accompanying drawings. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure.
The following describes embodiments of the present disclosure with reference to the accompanying drawings. It should be noted that the following embodiments are examples of specific embodiments of the present disclosure and should not limit the technical scope of the present disclosure.
As shown in
The image forming apparatus 10 is for electrophotographically forming an image on a sheet. The sheet is a sheet-like image forming medium, such as paper or resin film.
The image forming apparatus 10 includes a sheet supplying device 2, a sheet conveying device 3, a print processing device 40, an optical scanning device 46, a fixing device 49, the toner container 5, and a waste developer bottle 7.
The body 1 of the image forming apparatus 10 is a housing for storing the sheet conveying device 3, the print processing device 40, the optical scanning device 46, and the fixing device 49.
The print processing device 40 executes an image forming process for forming a toner image on the sheet. For example, the print processing device 40 executes the image forming process using a two-component developer including a toner 9 and a carrier. The carrier is a magnetic granular material.
The image forming apparatus 10 shown in
Each of the imaging units 4 includes a photoconductor 41, a charging device 42, a developing device 43, a primary transfer device 44, and a primary cleaning device 45.
The toner containers 5 are removably attached to a plurality of cartridge attaching portions 6 of the body 1, respectively. Each of the toner containers 5 includes a body 51 for storing the toner 9, and a screw feeder 52 for feeding the toner 9 from the body 51. The toner container 5 is configured to feed the toner 9 to the developing device 43 by action of the screw feeder 52. The screw feeder 52 is an example of a feeding mechanism. In addition, the body 51 is an example of a container body.
The toner 9 fed from the body 51 is supplied to the developing device 43. When the toner 9 in the body 51 of the toner container 5 is exhausted, the toner container 5 is exchanged.
The sheet supplying device 2 is configured to send the sheet to a sheet conveyance path 30 in the body 1, and the sheet conveying device 3 is configured to convey the sheet along the sheet conveyance path 30.
The drum-shaped photoconductor 41 is configured to rotate, and the charging device 42 charges a surface of the photoconductor 41. Furthermore, the optical scanning device 46 is configured to write an electrostatic latent image on the surface of the photoconductor 41 by scanning with laser light.
Furthermore, the developing device 43 develops the electrostatic latent image on the photoconductor 41 into a toner image. The toner image is a visible image of the toner 9. The primary transfer device 44 then transfers the toner image from the surface of the photoconductor 41 to the intermediate transfer belt 47. The primary cleaning device 45 removes the toner 9 remaining on the surface of the photoconductor 41.
It is noted that the photoconductor 41 and the intermediate transfer belt 47 are examples of an image-carrying member for holding an image of the toner 9.
The secondary transfer device 48 transfers a superimposed toner image formed on the intermediate transfer belt 47 to the sheet. The secondary cleaning device 470 removes the toner 9 remaining on the intermediate transfer belt 47. The fixing device 49 heats the superimposed toner image to fix it on the sheet.
The toner 9 removed from the photoconductors 41 and the intermediate transfer belt 47 by the primary cleaning devices 45 and the secondary cleaning device 470 is conveyed as waste developer 9a to the waste developer bottle 7, and is stored therein.
Furthermore, toner 9 floating inside the developing devices 43 and a portion of the carrier that has deteriorated in the developing devices 43 are also collected in the waste developer bottle 7 as the waste developer 9a. In other words, the waste developer bottle 7 is for storing the used waste developer 9a.
The waste developer bottle 7 is removably attached to a bottle attaching portion 70 of the body 1. When the waste developer 9a inside the waste developer bottle 7 exceeds a predetermined allowable amount, the waste developer bottle 7 is exchanged.
Meanwhile, in the toner container 5, it is desired to simplify a mechanism for feeding the toner 9 from the body 51 to the developing device 43, and save space.
In addition, when the toner 9 is fed from the body 51, pressure inside of the body 1 tends to become negative. Negative pressure inside the body 51 can interfere with feeding of the toner 9.
On the other hand, forming an opening for ventilation in the body 51 can solve the problem of negative pressure inside the body 51. However, the opening of the body 51 can cause toner leakage when the toner container 5 is being transported.
In the present embodiment, the toner container 5 has a structure that can simplify the mechanism for feeding the toner 9 from the body 51, and save space. Furthermore, the toner container 5 has a structure that can solve the problem of negative pressure inside the body 51, and the problem of toner leakage. The structure of the toner container 5 is described below.
As shown in
As mentioned above, the body 51 is for storing the toner 9. As shown in
The screw feeder 52 includes a shaft 521 and a blade 522. The shaft 521 is formed extending from inside the body 51 toward an entrance of the toner conveyance path 530. The blade 522 is formed protruding spirally from the shaft 521.
As shown in
The bearing portion 511 and a portion of the body 51 that connects with the tubular body 53 are provided on opposite sides of the body 51. The shaft 521 is rotatably cantilevered by the bearing portion 511. The portion of the body 51 that connects with the tubular body 53 is the inner diameter tapered portion 512.
As shown in
A part of the second shaft portion 5212 protrudes outward from the bearing portion 511 of the body 51. An engaging member 55 is fixed on the portion of the second shaft portion 5212 protruding from the body 51. When the toner container 5 is attached to the cartridge attaching portion 6, the engaging member 55 is connected to a driving mechanism 60 provided in the body 1.
The driving mechanism 60 applies a rotational force to the shaft 521 of the screw feeder 52 via the engaging member 55. This allows for the screw feeder 52 to rotate.
A longitudinal direction in the screw feeder 52 toward the first shaft portion 5211 from the second shaft portion 5212 is a toner feeding direction D0.
The screw feeder 52 includes a contour tapered portion 52a in which an outer diameter of the blade 522 gradually becomes smaller in the toner feeding direction D0.
As shown in
The inner diameter tapered portion 512 of the body 51 is formed in a tubular shape surrounding the periphery of the contour tapered portion 52a, the tubular shape gradually decreasing in inner diameter in the toner feeding direction D0.
An inner diameter of the tubular body 53 is smaller than a largest inner diameter of the inner diameter tapered portion 512. In addition, the inner diameter of the tubular body 53 is smaller than a largest outer diameter of the contour tapered portion 52a of the screw feeder 52.
The screw feeder 52 feeds the toner 9 in the body 51 to the toner conveyance path 530 by being rotationally driven inside the body 51. With this movement, the toner 9 fills a vicinity of the entrance of the toner conveyance path 530.
Furthermore, the screw feeder 52 pushes the toner 9 that has arrived inside the toner conveyance path 530 further along the toner conveyance path 530 by feeding pressure of succeeding toner 9. This allows for the toner 9 to entirely fill the toner conveyance path 530, and to be fed out from an outlet 53a of the toner conveyance path 530.
It is noted that until the toner container 5 is attached to the cartridge attaching portion 6 of the body 1, a cap (not shown) is attached to the tubular body 53. This cap covers the outlet 53a of the toner conveyance path 530. After removal of the cap from the tubular body 53, the toner container 5 is attached to the cartridge attaching portion 6 of the body 1.
The toner 9 fed out from the toner conveyance path 530 is supplied to the developing device 43 directly, or via an intermediate conveying path (not shown).
In the example shown in
As shown in
In addition, a direction through the vent 5130 from outside the body 51 toward the inside the body 51 is referred to as a first direction D1, and an opposite direction of the first direction D1 is referred to as a second direction D2 (see
Furthermore, the body 51 includes a guiding portion 514 formed extending in the first direction D1 around the opening edge portion 513. In the present embodiment, the opening edge portion 513 and the guiding portion 514 are formed along concentric circles.
The valve 54 is a mechanism that switches between a closed state and an open state, wherein the valve 54 blocks the vent 5130 in the closed state, and opens a portion of the vent 5130 in the open state.
As shown in
The first displacement member 541a includes a penetrating portion 5411 penetrating through the vent 5130, as well as a seal portion 5412, a first engaging portion 5413, and a flange portion 5414 all provided integrally with the penetrating portion 5411.
The seal portion 5412 is provided in an intermediate portion of the penetrating portion 5411. The first engaging portion 5413 is provided near a first end of the penetrating portion 5411, and the flange portion 5414 is provided on a second end of the penetrating portion 5411.
The first engaging portion 5413 is formed on a portion of the penetrating portion 5411 positioned inside the body 51. On the other hand, the flange portion 5414 is formed on a portion of the penetrating portion 5411 positioned outside the body 51.
The second displacement member 541b includes a second engaging portion 5415 and a stopper 5416. The first engaging portion 5413 and the second engaging portion 5415 engage with one another to integrally hold the first displacement member 541a and the second displacement member 541b together. The second displacement member 541b forms a portion of the displacement member 541 positioned inside the body 51.
The seal portion 5412 is formed along an entire circumference of an outer periphery of the penetrating portion 5411. In the present embodiment, the seal portion 5412 is a circular ring member fitted in close contact with the intermediate portion of the penetrating portion 5411.
As shown in
The displacement member 541 can be displaced between a closed position and an open position, wherein the seal portion 5412 blocks the vent 5130 in the closed position, and opens a portion of the vent 5130 in the open position.
The guiding portion 514 guides the flange portion 5414 of the displacement member 541 in the first direction D1 and the second direction D2 (see
In addition, the stopper 5416 of the displacement member 541 abuts against an inner surface of the body 51 when the displacement member 541 is in the closed position. With this configuration, the stopper 5416 limits displacement of the displacement member 541 in the second direction D2 (see
The seal portion 5412 blocks a gap between the penetrating portion 5411 and the opening edge portion 513 in the vent 5130 when the displacement member 541 is in the closed position (see
On the other hand, when the displacement member 541 is in the open position, the seal portion 5412 opens the gap between the penetrating portion 5411 and the opening edge portion 513 in the vent 5130 (see
In the present embodiment, a route passing through the two gaps, that is, the gap between the flange portion 5414 and the guiding portion 514, and the gap between the penetrating portion 5411 and the opening edge portion 513, is a route of the ventilation path R0.
The spring 542 holds the displacement member 541 in the closed position by applying elastic force to the flange portion 5414 of the displacement member 541. In the present embodiment, the spring 542 is a coil spring inserted inside the guiding portion 514. The spring 542 applies elastic force in the second direction D2 to the flange portion 5414 of the displacement member 541.
It is noted that the spring 542 is an example of an elastic member. Another elastic member such as rubber may also be adopted in place of the spring 542.
As shown in
The protruding portion 6a holds the displacement member 541 in the open position against the elastic force of the spring 542, by abutting against the flange portion 5414 of the displacement member 541.
As described above, in conjunction with a displacement of the displacement member 541 from the closed position in the first direction D1, the seal portion 5412 is displaced from one position to another, the first position being where the seal portion 5412 blocks the gap between the opening edge portion 513 and the penetrating portion 5411 that form the edges of the vent 5130 of the body 51, and the other position being inside the body 51 away from the opening edge portion 513.
By adopting the toner container 5, it is unnecessary to provide the screw feeder 52 inside the toner conveyance path 530. This allows for the screw feeder 52 to be shortened, and to make the cylindrical body 53 narrower. Accordingly, it is possible to simplify the mechanism for feeding the toner 9 from the body 51, and save space.
In addition, by the action of the inner diameter tapered portion 512 and the contour tapered portion 52a, the toner 9 is smoothly fed from the body 51 to the toner conveyance path 530 in the cylindrical body 53.
In addition, when the toner container 5 is not attached to the body 1, the valve 54 blocks the vent 5130 of the body 51. This allows for the valve 54 to prevent the toner 9 from leaking from the body 51 when the toner container 5 is being transported.
In addition, when the toner container 5 is attached to the body 1, the valve 54 opens a portion of the vent 5130 of the body 51. This prevents the feeding of the toner 9 from causing negative pressure inside the body 51.
In the toner container 5, the toner 9 is conveyed in a state where the toner conveyance path 530 in the cylindrical body 53 is filled with the toner 9. In this case, the negative pressure in the body 51 disturbs the feeding of the toner 9 from the body 51. Thus, the valve 54 has a remarkable effect.
Next, with reference to
Below, a description is given of a point in the toner container 5A that is different from the toner container 5. The toner container 5A has a configuration in which a filter 543 is added to the toner container 5.
When the displacement member 541 is in the open position, the filter 543 covers a space on the outside of the body 51 communicating with the vent 5130 (see
In the present embodiment, the filter 543 is a cylindrical member surrounding a periphery of the opening edge portion 513. When the displacement member 541 is in the open position, the filter 543 covers a gap between the flange portion 5414 of the displacement member 541 and an outer surface of the body 51.
For example, the filter 543 may be an open-cell foam sponge. The open-cell foam sponge is an example of an open-cell foam body made of an elastic material, such as rubber.
Adopting the toner container 5A achieves the same effect as in a case where the toner container 5 is adopted. Furthermore, in a state where the toner container 5A is attached to the body 1, the filter 543 prevents leaking of the toner 9 from the body 51 when the screw feeder 52 is not moving.
In the toner container 5, the valve 54 may be omitted. In this case, the filter 543 may be fixed to the body 51 in a state where the filter 543 covers the vent 5130 of the body 51.
It is to be understood that the embodiments herein are illustrative and not restrictive, since the scope of the disclosure is defined by the appended claims rather than by the description preceding them, and all changes that fall within metes and bounds of the claims, or equivalence of such metes and bounds thereof are therefore intended to be embraced by the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2017-203376 | Oct 2017 | JP | national |
