Patent Grant
9471006
The present invention relates to a developer accommodating unit for accommodating a developer, and a process cartridge and an electrophotographic image forming apparatus which include the developer accommodating unit.
The electrophotographic image forming apparatus forms an image on a recording material (medium) by using an electrophotographic image forming process and may include, e.g., an electrophotographic copying machine, an electrophotographic printer (such as an LED printer or a laser beam printer), an electrophotographic facsimile machine, an electrophotographic word processor, and the like. Further, the process cartridge refers to a cartridge, prepared by integrally assembling at least a developing means and a developer accommodating unit accommodating a developer, detachably mountable to a main assembly of the electrophotographic image forming apparatus.
In a conventional electrophotographic image forming apparatus using the electrophotographic image forming process, a process cartridge type in which an electrophotographic photosensitive member and process means acting on the photosensitive member are integrally assembled into a cartridge and this cartridge is detachably mountable to a main assembly of the electrophotographic image forming apparatus is employed.
In such a process cartridge, a type in which an opening provided to a developer accommodating frame for accommodating a developer (toner, carrier, etc.) is sealed with a sealing member, and then a welding portion of as a sealing member is peeled off at the time of use to unseal the opening, thus enabling feeding (supply) of the developer has been widely employed. As an invention in which the opening of the developer accommodating frame is opened, those described in Japanese Laid-Open Patent Application (JP-A) Hei 4-166963, JP-A 2002-169366 and JP-A Sho 63-294582 are disclosed.
In JP-A Hei 4-166963, a constitution in which a toner accommodating portion formed with a sheet film is provided inside the developer accommodating frame and when a user pulls a grip, a developer supplying opening of the toner accommodating portion is opened is described. In JP-A 2002-169366, a constitution in which a winding-up shaft of a sealing member is provided outside the developer accommodating frame is provided and when the winding-up shaft is rotated, the developer supplying opening is opened is described. In JP-A Sho 63-294528, a constitution in which the winding-up shaft of the sealing member is provided inside the developer accommodating frame and when the winding-up shaft is rotated, the developer supplying opening is opened is described.
However, in the constitution described in JP-A Hei 4-166963, the user is required to expend effort such that the user pulls the grip, and the sealing member remains in user's hand. Further, in the constitutions described in JP-A 2002-169366 and JP-A Sho 63-249582, the sealing member is peeled off but it is desired that discharging efficiency of the developer is further improved.
A principal object of the present invention is to provide a developer accommodating unit capable of eliminating efforts of a user to remove a sealing member and capable of improving discharging efficiency of a developer from a flexible container in which the developer is accommodated.
According to an aspect of the present invention, there is provided a developer accommodating unit comprising: a container, provided with an opening for permitting discharge of a developer, for accommodating the developer; a sealing member for sealing the opening by being mounted on the container and for being peeled from the container to expose the opening; and an unsealing member for unsealing the opening by moving the sealing member to peel the sealing member from the container, wherein the sealing member includes a sealing portion defined in an end side thereof to seal the opening, a holding portion defined in another end side thereof to be held by the unsealing member, and a developer passing portion formed between the sealing portion and the holding portion to permit passing of the developer therethrough.
These and other objects, features and advantages of the present invention will become more apparent upon a consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.
Hereinbelow, embodiments for carrying out the present invention will be exemplarily and specifically described on the basis of Embodiments with reference to the drawings. However, dimensions, materials, shapes, relative arrangements, and the like of constituent elements described in the following embodiments are appropriately changed depending on constitutions or various conditions of devices (apparatuses) to which the present invention is applied, and therefore the scope of the present invention is not limited thereto unless otherwise specified.
Inside the apparatus main assembly B1 of the image forming apparatus B, the image forming portion Q, a cassette 6 and a fixing device 10 are provided. The image forming portion Q includes a cleaner unit 24 including the photosensitive drum 11, a developer accommodating unit 25, an exposure device 8, and the transfer roller 9. Of these members, a cartridge A is constituted principally by the cleaner unit 24 and the developer accommodating unit 25. Further, in a conveying path of a sheet S, members consisting of the cassette 6, the transfer roller 9, the fixing device 10, a discharging roller pair 1 and a discharge portion 3 where the discharged sheet S is to be stacked, are provided in this order.
For image formation, in synchronism with the conveyance of the sheet S from the cassette 6, the exposure device 8 selectively exposes the surface of the photosensitive drum 11 to light, so that an electrostatic latent image is formed on the surface of the photosensitive drum 11. Thereafter, the developer accommodated in a developer bag 16 is carried in a thin layer on the surface of a developing roller 13 by a developing blade 15. Then, a developing bias is applied to the developing roller 13 as a developer carrying member, so that depending on the electrostatic latent image, the developer is supplied from the developing roller 13 to the surface of the photosensitive drum 11.
On the other hand, the sheet S is conveyed from the cassette 6 to a nip between the photosensitive drum 11 and the transfer roller 9. The developer image formed on the surface of the photosensitive drum 11 by changing, exposure and development, is transferred onto the sheet S by the transfer roller 9 supplied with a bias voltage. Then, the sheet S on which the developer image is transferred is conveyed to the fixing device 10 to fix the developer image thereon, and then is discharged onto the discharge portion 3 at an upper surface of the apparatus main assembly B1 by the discharging roller pair 1.
The cartridge A as the process cartridge includes the cleaner unit 24 including the photosensitive drum 11 as the image bearing member, a charging roller 12 as the charging means, an elastic cleaning blade 14 as the cleaning means. Further, the cartridge includes the developer accommodating unit 25 including the developing roller 13 and a developing blade 15 which are a developing means, the developer bag 16 accommodating the developer, and a first frame 17 and a second frame 18 which support the developing roller 13 and the developing blade 15. Incidentally, the frame a 17 and 18 accommodate a developer accommodating container 30 and an unsealing member 20 described later.
Further, the cleaner unit 24 and the developer accommodating unit 25 are integrally assembled in the cartridge A and is constituted so as to be detachably mountable to the apparatus main assembly B1 (
Further, the sealing member 19 is mounted on the developing bag 16 in order to seal the openings 16c, and exposes the openings 16c when being peeled from the developing bag 16. Specifically, the sealing member 19 is applied onto the discharging portion 16b to seal the openings 16c so as to prevent the developer inside the developing bag 16 from leaking out of the developer bag 16. The sealing member 19 is formed in a sheet shape.
Further, the unsealing member 20 is mounted on the sealing member 19 at an end portion of the sealing member 19. When the unsealing member 20 is rotated in the arrow C direction, the sealing member 19 is rotated to open the openings 16c of the developer bag 16. Thus, the unsealing member 20 unseals the openings 16c by operating the sealing member 19 to peel the sealing member 19 from the developing bag 16. As a result, the developer comes out of the developer bag 16.
The connecting portion 19c is provided with a plurality of holes 19n (
The unsealing member 20 is rotatably supported about its shaft by the frames 17 and 18. The unsealing member 20 corresponds to a shaft rotatably supported by the first frame 17 and includes a first fixing side 20x and a second fixing side 20y. Each of the first fixing side 20x and the second fixing side 20y is constituted by a flat surface substantially parallel to an axis of the unsealing member 20. In the first fixing side 20x, the holding portion 19b of the sealing member 19 is fixed, and in the second fixing side 20y, a holding portion 21b of an urging member 21 in a base end side is fixed. The holding portion 21b of the urging member 21 is fixed on the second fixing side 20y by a fourth welding portion 20d, and the urging member 21 urges the developer bag 16 in its leading (free) end side by being rotated. The urging member 21 is disposed inside the frames 17 and 18, and urges the developing bag 16 to deform the developing bag 16.
Next, a fixing state of the inside members of the developer accommodating unit 25 will be described. For fixing, (heat) welding, ultrasonic welding, bonding, pseudo-bonding or the like is employed. The sealing member 19 is fixed on the discharging portion 16b at the sealing portion 19a in the leading end side in a peelable manner, thus sealing the openings 16c. The sealing member 19 is fixed on the unsealing member 20 at the holding portion 19b in the base end side.
As the fixing means, in addition to the welding, the ultrasonic welding, the bonding and the pseudo-bonding, it is possible to use clamping by grip-shaped portions, hanging by holes and projections, and the like.
The developing bag 16, the sealing member 19 and the unsealing member 20 are accommodated in the first frame 17 and are also covered with the second frame 18. Then, the first frame 17 and the second frame 18 are bonded by the welding, the bonding or the like, so that the respective members are accommodated inside the developer accommodating unit 25. The developer bag 16 is provided with fixing holes 16x and 16y.
A fixing portion 116x is fixed to the first frame 17 through the fixing holes 16x. A fixing portion 116y for connecting the first frame 17 and the second frame 18 is fixed to the first frame 17 and the second frame 18 through the holes 16y. The fixing portions 116x and 116y are fixed to at least one of the first and second frames 17 and 18 by using, e.g., a double-side tape, a wedge-shaped member, a hook-shaped member, the welding, the ultrasonic welding or the bonding. Incidentally, the developing bag 16 is provided with the fixing holes 16x and 16y in a flat side (surface) substantially parallel to the axis of the unsealing member 20.
Next, details and a mutual relationship of the respective members of the developing bag 16 will be described with reference to the drawings 3, 4 and 5. The developing bag 16 includes the discharging portion 16b and is clogged by the sealing member 19 as described above. Other sides of the developing bag 16 constitutes a folding-back portion of the bag material or a bag-shaped portion by firmly bonding bag materials to each other by using the welding, the ultrasonic welding, the bonding or the like. In order to realize the unsealing by the above-described constitution, there is a need to always peel the discharging portion 16b first, and therefore it is essential that at all of bonding portions of the developing bag 16, strength, i.e., a peeling force of each bonding portion between the sealing member 19 and the developer bag 16 is weakest. This is true for other portions. With respect to a fixing force between the sealing member 19 and the unsealing member 20, a fixing force between the developer bag 16 and the first frame 17 or the second frame 18, or the like force, it is essential that the above-described peeling force is weakest.
On the other hand, the developer accommodating unit 25 functionally accommodates the toner therein, and therefore from the viewpoint of a sealing property, a larger peeling force to the possible extent is advantageous. This is because when the peeling force is large, there is a high possibility that a status in which the openings are unsealed in a state other than an intended state (in which the developer accommodating unit 25 is set in the image forming apparatus B) in the case where an unexpected force (e.g., an impact force during drop) can be avoided. From the above, the peeling force is required to be set at a desired value.
A method of setting the peeling force at the desired value will be described. In this embodiment, in order to set the peeling force at the desired value (a minimum force within a range in which the toner sealing property can be maintained), two methods are principally employed.
In a first method, a laminate material having a special sealant layer which exhibits an easy peeling property (peeling strength of about 3 N/15 mm in testing methods for heat sealed flexible packages according to JIS-Z0238) is applied. Further, the first method is a method in which the easy peeling property is exhibited at the peeling portion by using, as the material (member) for the developer bag 16, a sheet material (of, e.g., polyethylene or polypropylene) which is weldable with the special sealant layer and which has flexibility. By changing a combination of formulation of the special sealant layer with the material to be bonded, the peeling force can be reduced.
A second method is a method in which as shown in
Next, an effect obtained by employing the constitution in this embodiment will be described. As described above, by appropriately shaping the bonding portions between the developer bag 16 and the sealing member 19 and by using the laminate material having the special sealant layer which exhibits the easy peeling property, it is possible to unseal the openings of the developer bag 16 with a small force (the peeling force of about 3 N/15 mm at the portion to be unsealed).
The sealing portion 19a is welded at the peripheral portion 16f of the connecting portion 19c connecting the openings 16c, thus sealing the openings 16c. Specifically, the peripheral portion 16f of the openings 16c is sealed by the first welding portion 16d, the second welding portion 16e and a widthwise welding portion 16p. The first welding portion 16d is welded at the peripheral portion 16f in the base end side of the sealing portion 16a. The second welding portion 16e is welded at the peripheral portion 16f in the leading end side of the sealing portion 16a. The widthwise welding portion 16p is welded at the peripheral portion 16f so as to connect the first welding portion 16d and the second welding portion 16e at each of longitudinal end portions of the openings 16c. Incidentally, as shown in
When the unsealing member 20 is rotated in the arrow C direction, the sealing member 19 is pulled in an arrow D direction (
As described above, when the developer is discharged, it is desirable that there is no member in the neighborhood of the openings 16c. This is because powder such as the developer has a flowing speed which is slow when it passes through a narrow range and therefore a discharging speed is lowered.
As described above, the unsealing of the discharging portion 16b of the developer bag 16 is enabled by only pulling the sealing member 19 in one direction (arrow D direction) by the unsealing member 20, so that the openings 16c of the developer bag 16 is stably unsealed with reliability. Further, the cartridge A is pulled in a widthwise direction perpendicular to a longitudinal direction, so that the developer bag 16 can be unsealed, and therefore a peeling distance which is about two times a longitudinal distance of a conventional cartridge can be considerably reduced. The sealing member 19 after being unsealed is fixed on the unsealing member 20, so that it is possible to unseal the developer bag 16 without generating a waste member from the process cartridge.
Further, by the urging member 21 and the holes 19n, the discharge of the developer from the inside of the developer bag 16 is quickly made with reliability, thus leading to a reduction in time required from insertion to a printable state of the process cartridge. Further, the developer bag 16 has a bag shape, so that the developer can be treated as a unit, and therefore a developer filling step can be separated from a process cartridge assembling step.
The developer bag 16 has flexibility and does not have a completely defined shape, so that there is a need to ensure a clearance where the developer bag 16 is assembled with the first frame 17. For that reason, at an end portion of the unsealing member 20 with respect to a rotational axis direction, a space (indicated by an arrow N) where the developer bag 16 is assembled with the first frame 17 is ensured. With respect to the discharge of the developer after the sealing portion 19a is peeled, it is desirable that a discharging amount of the developer at the end portion is larger than at a central portion with respect to the rotational axis direction.
It would be also considered that all the holes 19n are formed in a larger size to the possible extent, but a range in which the size can be increased is limited by a balance with the strength (stiffness). The size of each of the openings 19n at the central portion and end portions of the unsealing member 20 with respect to the rotational axis direction may only be required to be determined within the range.
By the constitution described above, in addition to the effect in Embodiment 1, an insufficient feeding force to the end portions can be compensated by ensuring the assembling space, so that also the developer discharge is quickly performed with reliability. Accordingly, the time required from the insertion to the printable state of the process cartridge can be reduced.
According to the constitution in Embodiment 1, there is no effort of the user to remove the unsealing member, so that the developer discharging efficiency from the developer bag 16 in which the developer is accommodated. Particularly, while using the sealing member 19 for improving flowability of the developer, it is possible to suppress a phenomenon that flow of the developer which flows from the openings 16c is prevented by the sealing member 19 after the unsealing member 20 is operated to release the sealing of the openings 16c by the sealing member 19. Further, in this way, by employing the constitution in which the release of the sealing by the sealing member 19 can be effected by the inside member, there is no need for the user to pull out the sealing member 19 of the cartridge A, so that the cartridge A can be replaced simply. This is true for also the constitutions in Embodiments 2 and 3.
According to the constitution in Embodiment 3, the holes 19n2 of the continuous member 19c1 are formed in the larger size at the end portion than at the central portion. As a result, the developer can pass through the holes 19n1 in the central side and concurrently can pass through the holes 19n2 in the end side at a higher efficiency than that in the central side.
According to the constitution in Embodiment 4, the holes 19n2 of the continuous member 19c1 are formed in the small size than the surface and the holding portion 19b with respect to the axial direction R of the unsealing member 20. As a result, the developer can pass through the holes 19n and concurrently can pass through a portion outside a cut-away portion 419X of the continuous member 19c1 with respect to the axial direction R of the unsealing member 20.
According to the present invention, there is no effort of the user to remove the sealing member, and the developer discharging efficiency from the flexible container in which the developer is accommodated is improved.
While the invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth and this application is intended to cover such modifications or changes as may come within the purpose of the improvements or the scope of the following claims.
This application claims priority from Japanese Patent Application No. 115868/2012 filed May 21, 2012, which is hereby incorporated by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012-115868 | May 2012 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 5075727 | Nakatomi | Dec 1991 | A |
| 5264901 | Rossiter | Nov 1993 | A |
| 5594535 | Beaufort et al. | Jan 1997 | A |
| 8385787 | Yamaguchi et al. | Feb 2013 | B2 |
| Number | Date | Country |
|---|---|---|
| 63-130978 | Dec 1988 | JP |
| 04-166963 | Jun 1992 | JP |
| 2002-169366 | Jun 2002 | JP |
| 2011-047981 | Mar 2011 | JP |
| Entry |
|---|
| English translation of JP 2011-047981 (Mar. 10, 2011). |
| Number | Date | Country | |
|---|---|---|---|
| 20150355577 A1 | Dec 2015 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 13897768 | May 2013 | US |
| Child | 14830164 | US |
