The present invention relates to a developer accommodating unit for accommodating a developer, and a developing device, a process cartridge and an electrophotographic image forming apparatus which includes the developer accommodating unit.
Here, the image forming apparatus forms an image on a recording material (medium) by using, e.g., 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 and the like. The process cartridge refers to a cartridge which is prepared by integrally mounting at least an image bearing member, a developer carrying member and a developer accommodating unit into a unit and which is made detachably mountable to an image forming apparatus or which is fastened to the image forming apparatus.
Further, the developer accommodating unit is to be accommodated in the image forming apparatus or the process cartridge. The developer accommodating unit at least includes a flexible container for accommodating the developer.
In a conventional electrophotographic image forming apparatus using an electrophotographic image forming process, a cartridge type in which consumables are integrally assembled into a cartridge and the cartridge is made detachably mountable to the image forming apparatus has been employed. As this cartridge, e.g., a process cartridge prepared by integrally assembling an electrophotographic photosensitive member and process means actable on the photosensitive member into a cartridge, and the developer accommodating unit or the like in which the developer is accommodated have been known.
In such a process cartridge, as shown in
Further, a constitution in which in order to solve a problem of scattering of the developer in a cartridge in a developer filling step during manufacturing of the cartridge, a deformable developer accommodating container in which the developer is accommodated is used and accommodated in a frame has been proposed(Japanese Laid-Open Patent Application (JP-A) Hei 4-66980).
However, in order to realize lifetime extension of the cartridge without upsizing the image forming apparatus, to would be considered that the developer is accommodated in a larger amount in the developer accommodating container larger than the frame constituting the cartridge is accommodated in the frame by being depressed (deformed). In this case, there was a possibility that the frame is deformed by a repelling force of the deformable developer accommodating container. Further, by the deformation of the frame, there was a possibility that positions of members, such as a developer carrying member and a developing blade, supported by the frame were changed to lower an image quality.
A principal object of the present invention is to provide a developer accommodating unit and the like having a long lifetime without upsizing an image forming apparatus.
According to an aspect of the present invention, there is provided a developer accommodating unit for accommodating a developer, comprising: a flexible container, provided with an opening for permitting discharge of the developer, for accommodating the developer; a sealing member for sealing the opening; and a frame, including a first frame and a second frame, for accommodating the flexible container in a space formed by mounting the first frame to the second frame and for accommodating the developer discharged through the opening of the flexible container when the opening is unsealed, wherein the flexible container is deformed adjacent to longitudinal end portions thereof in a mounting direction of the first frame toward the second frame.
According to another aspect of the present invention, there are provided a developing device, a process cartridge and an image forming apparatus each including the developer accommodating unit.
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.
Parts (a), (b) and (c) of
Parts (a) and (b) of
Parts (a) and (b) of
Parts (a), (b) and (c) of
Parts (a), (b) and (c) of
Parts (a) and (b) of
Parts (a), (b) and (c) of
Parts (a), (b) and (c) of
With reference to the drawings, preferred embodiments of the present invention will be exemplarily described specifically below. However, dimensions, materials, shapes, functions and relative arrangements of constituent elements described in the following embodiments should be appropriately modified depending on constitutions and various conditions of an apparatus to which the present invention is applied, and therefore, the scope of the present invention is not limited to the following embodiments, unless otherwise specified. Further, in the following description, materials, shapes and the like of members which have already described are the same as those first described unless otherwise specified.
With reference to the drawings, a process cartridge and an image forming apparatus each including a developer accommodating unit in this embodiment will be described below as an example. Incidentally, in the following description, a longitudinal direction coincides with a direction of a long side of a box-shaped developer accommodating unit 25 or developing device 38 as shown in (b) of
The process cartridge A includes, as shown in
The process cartridge A in this embodiment integrally including a cleaner unit 24 and the developing device 38 as shown in
The process cartridge A is detachably mounted in the image forming apparatus B as shown in
Next, a structure of a developer accommodating unit 25 will be described with reference to
The developer accommodating unit 25 is, as shown in
Incidentally, in this embodiment, the developer accommodating unit 25 is the same as the developing device 38. This is because the developer accommodating unit 25 includes the developing roller 13 and the developing blade 15. However, the developing roller 13 and the developing blade 15 may also be supported by a frame other than the frame for the developer accommodating unit 25, thus being separated from the developer accommodating unit 25. In this case, the developing device 38 is constituted by the developer accommodating unit 25, the developing roller 13 and the developing blade 25 (not shown).
A structure of the developer accommodating container 26 will be described with reference to
As shown in
Further, a degree of the air permeability of the air-permeable portion 34b may appropriately be selected, in view of a size (powder particle size) of the developer T, so as not to permit leakage of the developer T to the outside of the developer accommodating container 26. As a material for the air-permeable portion 34b, a nonwoven fabric formed of polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP) or the like in a thickness of 0.03-0.25 mm may preferably be used. Incidentally, the material for the air-permeable portion 34b is not limited to the nonwoven fabric but may also be a material provided with minute holes each smaller than the size of the powder such as the developer to be accommodated in the developer accommodating container 26.
At a part of an outer peripheral portion 34c of the developer accommodating member 34, holes 34g as a portion-to-be-fixed of the developer accommodating member 34 on the second frame 18 are provided. Further, the second frame 18 is provided with bosses 18b as a fixing portion for fixing the developer accommodating member 34 on the second frame 18. The developer accommodating container 26 is positioned relative to the second frame 18 by engaging the holes 34g of the developer accommodating member 34 with the bosses 18b of the second frame 18. Thereafter, the bosses 18b are melted by ultrasonic caulking, so that the developer accommodating container 26 is fixed to the second frame 18. As a fixing means, in addition to the ultrasonic caulking, it is also possible to use other means without using ultrasonic wave. For example, the fixing means may also be thermal caulking using heat, bonding using a solvent or an adhesive, insertion between the frames, hooking using a hole and a projection (boss or the like), etc.
Incidentally, a mounting method of the first frame 17 to the second developing roller 18 will be described later.
Further, the developer accommodating member 34 is provided with a discharging portion 35 as an opening for permitting discharge of the developer T. In order to prevent leaking-out of the developer T from the developer accommodating member 34 of the process cartridge A before use, the sealing member 19 is bonded to the developer accommodating member 34 so as to cover the discharging portion 35. The sealing member 19 is a flexible sheet-like member and is used for sealing the discharging portion 35. The sealing member 19 is peeled off from the developer accommodating member 34 to expose the discharging portion 35, and thus is capable of discharging the developer T from the developer accommodating member 34. Here, the holes 34g and the bosses 18b are provided in parallel to a longitudinal direction (long side direction) F of the developer accommodating member 34, and receive a force when the sealing member 19 is unsealed from the developer accommodating member 34.
Further, the sealing member 19 is connected with an unsealing member 20 at a portion-to-be-engaged 19b, and the unsealing member 20 is rotatably supported by the second frame 18. The unsealing member 20 is rotated in an arrow C direction by transmitting a driving force thereto by an unshown driving means provided in the image forming apparatus B, thus being capable of winding up the sealing member 19 to expose the discharging portion 35. Incidentally, herein a constitution in which the sealing member 19 is automatically unsealed is shown as an example, but the present invention is not limited thereto. For example, a manually unsealing constitution such that the sealing member is pulled out in the longitudinal direction to be unsealed may also be employed.
Here, the discharging portion 35 may desirably be configured so that the discharging portion 35 is in an attitude during image formation to permit easy discharge of the developer T. For that purpose, in this embodiment, in the attitude during the image formation, the discharging portion 35 is disposed vertically downward.
The structure of the developer accommodating container 26 will be specifically described with reference to
As shown in (a) and (b) of
That is, each of the distances L1 and L2 provides a largest portion between the surface opposing the first frame 17 and the surface opposing the second developing roller 18 with respect to the mounting direction of the developer accommodating container 26 at the longitudinal end portion. Further, the distance L3 provides a largest portion between the surface opposing the first frame 17 and the surface opposing the second frame 18 with respect to the mounting direction of the developer accommodating container 26 at the longitudinal central portion. In this case, L1 and L2 are larger than L3.
Further, each of a thickness t1 of an end surface 26d and a thickness t2 of an end surface 26e with respect to the longitudinal direction F of the developer accommodating container 26 is thinner than a thickness t3 of the end portion surface 26a, a thickness t4 of the end portion surface 26b and a thickness t5 of the central portion surface 26c with respect to a direction in which these portions are provided, crossing the mounting direction. That is, (t1<t3, t4, t5) and (t2<t3, t4, t5) are satisfied.
Further, the end surfaces 26d and 26e of the developer accommodating container 26 are inclined by angles θ1 and θ2, respectively, with respect to the mounting direction E of the first frame (not shown). Here, the angles θ1 and θ2 satisfy (0 degrees<θ1<90 degrees) and (0 degrees<θ2<90 degrees), respectively, and in this embodiment, θ1=3 degrees and θ2=3 degrees are set. The reason therefor will be described later.
Next, a mounting method of the developer accommodating container 26 to the frame 40 will be described with reference to
Incidentally, the first state of the developer accommodating container 26 indicated by the chain double-dashed line is a state in which an external force is not applied to the longitudinal end portions. It can also be said that the first state is a natural state in which the external force is not applied. On the other hand, a state of the developer accommodating container 26 indicated by a solid line in (c) of
As shown in (a) of
Next, as shown in (b) of
Next, as indicated by the chain double-dashed line in (c) of
That is, when the first frame 17 is moved from the state of (b) of
Here, longitudinal end portion surfaces 26a1 and 26a2 of the developer accommodating container 26 in the second state in which the developer accommodating container 26 is deformed and depressed by the opposing surface 17a and thus is accommodated in the frame 40 are indicated by the solid line in (c) of
For that reason, the frame 40 formed by the first frame 17 and the second frame 18 receives reaction forces P1 and P2 by depressing the developer accommodating container 26 at longitudinal end portion surfaces 40a and 40b, respectively. Incidentally, each of the reaction forces P1 and P2 is a resultant force of the following three forces. A first force is a force P1A (or P2A) for deforming the developer accommodating container 26 having the flexibility. A second force is a force P1B (or P2B) for letting the air, inside of the developer accommodating container 26, escape through the air-permeable portion 34b when the developer accommodating container 26 is depressed by the frame 40. A third force is a force P1C (or P2C) for pushing aside the developer inside of the developer accommodating container 26. The deforming forces P1A and P2A, the escaping forces P1B and P2B and the pushing-aside forces P1C and P2C are indicated only in one direction in (c) of
Here, the frame 40 has a box-like shape extending in the longitudinal direction F as shown in (b) of
Further, as described above, each of the thickness t1 of the end surface 26d and the thickness t2 of the end surface 26e of the developer accommodating container 26 is thinner than each of the thickness t3 of the end portion surface 26a, the thickness t4 of the end portion surface 26b and the thickness t5 of the central portion surface 26c of the developer accommodating container 26 provided along the direction crossing the mounting direction. For that reason, the end surfaces 26d and 26e of the developer accommodating container 26 are liable to cause buckling deformation with respect to the mounting direction E, so that the forces P1A and P2A for deforming the developer accommodating container 26 become small. Accordingly, the reaction forces P1 and P2 are smaller than those in the case where the developer accommodating container 26 is formed in a uniform thickness as a whole.
Here, during the mounting of the developer accommodating container 26 to the frame 40 and when the developer T is filled in the developer accommodating container 26, in order to maintain a shape of the developer accommodating container 26, the developer accommodating container 26 is required to have a certain thickness. However, a surface area of the end surfaces 26d and 26e is smaller than a surface area of the developer accommodating container 26 as whole, and therefore the influence on maintenance of the shape of the developer accommodating container 26 is small. For that reason, the thicknesses of the end surfaces 26d and 26e can be made thin.
Further, as described above, the end surfaces 26d and 26c of the developer accommodating container 26 are inclined by the angles θ1 and θ2, respectively, with respect to the mounting direction of the first frame 17 with the second frame 18. For that reason, the forces P1A and P2A for deforming the developer accommodating container 26 act as component forces P1D=P1A cos θ1 and P2D=P2A cos θ2, respectively, with respect to the mounting direction in which the reaction forces P1 and P2 are generated. Accordingly, the reaction forces P1 and P2 are smaller than those in the case where the end surfaces 26a and 26e are formed in parallel to the mounting direction E.
Incidentally, between the end surface 26d of the developer accommodating container 26 and the end surface 40d of the frame 40 and between the end surface 26e of the developer accommodating container 26 and the end surface 40e of the frame 40, spacings L6 and L7 are provided, respectively, with respect to the longitudinal direction F. For that reason, at projected portions 26d1 and 26e1 generated by flexure of the end surfaces 26a and 26e generated by the depression of the end portion surfaces 26a and 26b, the developer T moved by the depression of the end portion surfaces 26a and 26b can be accommodated. Here, the projected portions 26d1 and 26e1 of the developer accommodating container 26 in a state in which the developer accommodating container 26 is accommodated between the first frame 17 and the second frame 18 are indicated by the solid line in (c) of
By the above-described constitution, even in the case where the developer accommodating container 26 including the depressed longitudinal end portions is accommodated in the frame 40, the degree of the deformation of the frame 40 by the reaction forces P1 and P2 of the developer accommodating container 26 can be decreased. For that reason, it is possible to decrease a degree of positional change of the process means such as the developing roller 13 to be mounted on the frame 40, so that the developing device 38 having a good image quality can be provided. Further, it is possible to provide the developer accommodating unit 25, the developing device 38, the process cartridge A and the image forming apparatus B which have a long lifetime without upsizing the frame 40 and by extension to the image forming apparatus B.
Incidentally, each of a thickness t6 of an inclined portion surface 26f between the end portion surface 26a and the central portion surface 26c and a thickness t7 of an inclined portion surface 26g between the end portion surface 26b and the central portion surface 26c may desirably be thinner than each of the thickness t3 of the end portion surface 26a, the thickness t4 of the end portion surface 26b and the thickness t5 of the central portion surface 26c. As a result, the developer accommodating container 26 easily causes the buckling deformation with respect to the mounting direction E, so that the forces P1A and P2A for deforming the developer accommodating container 26 become small.
Incidentally, the inclined portion surfaces 26f and 26g may desirably be inclined (e.g., with angles θ3 and θ4, respectively, shown in
Incidentally, in this embodiment, suppression of the deformation of the frame 40 by the reaction forces P1 and P2 when the first frame 17 was mounted to the second developing roller 18 was described. However, when the first frame 17 is mounted to the second frame 18, a similar effect can be obtained even in the case where the first frame 17 is mounted to the second frame 18 in a state (second state) in which the flexible developer accommodating container 26 is deformed and depressed in advance so as to be smaller in size than the frame 40. This is because even in the case where the flexible developer accommodating container 26 is deformed and depressed in advance so as to be smaller in size than the frame 40, the air flows into the inside of the developer accommodating container 26 through the air-permeable portion 34 after the first frame 17 is mounted to the second frame 18. Then, by the flow of the air into the inside of the developer accommodating container 26, a restoring force for restoring the shape of the developer accommodating container 26 to the original shape acts on the developer accommodating container 26. Accordingly, even in the case where the first frame 17 is mounted to the second frame 18 in the state in which the flexible developer accommodating container 26 is deformed and depressed in advance so as to be smaller in size than the frame 40, the reaction forces P1 and P2 of the developer accommodating container 26 are exerted on the first frame 17 and the second developing roller 18, respectively.
Incidentally, the depressing direction of the developer accommodating container 26 may be any direction if the depressing direction is substantially the same as the mounting direction of the first frame 17 with the second developing roller 18.
Incidentally, in this embodiment, an example in which the end surfaces 26d and 26e of the developer accommodating container 26 are deformed when the first frame 17 is mounted toward the second frame 18 was described. However, as shown in (a) and (b) of FIG. 10, when the first frame 17 is mounted toward the second frame 18, in addition to the deformation of the end surfaces 26d and 26e described above, it is also possible to deform an end surface 26k, of the developer accommodating container 26 with respect to a widthwise direction (short side direction) G, simultaneously with the deformation of the end surfaces 26d and 26e. The deformation of the end surface 26k with respect to the widthwise direction G will be described in an embodiment described later. Each of (a) and (b) of
Next, with reference to
Parts (a) to (c) of
Incidentally, the first state of the developer accommodating container 126 indicated by the chain double-dashed line shown in (c) of
As shown in (a) of
A fixing method of the developer accommodating container 126 to the second frame 118 is the same as that in Embodiment 1.
Next, as shown in (b) of
Next, as indicated by the chain double-dashed line in (c) of
That is, when the first frame 117 is moved from the state of (b) of
Here, longitudinal end portion surfaces 126a1 and 126a2 of the developer accommodating container 126 in the second state in which the developer accommodating container 126 is deformed and depressed by the opposing surface 117a and thus is accommodated in the frame 140 are indicated by the solid line in (c) of
For that reason, the frame 140 formed by the first frame 117 and the second frame 118 receives reaction forces P11 and P12 by depressing the developer accommodating container 126 at longitudinal end portion surfaces 140a and 140b, respectively. Incidentally, each of the reaction forces P11 and P12 is a resultant force of a force P1A (or P2A) for deforming the developer accommodating container 126 having the flexibility and a force P1C (or P2C) for pushing aside the developer inside of the developer accommodating container 126.
Here, the frame 140 has a box-like shape extending in the longitudinal direction F as shown in (b) of
Further, as described above, each of the thickness t11 of the end surface 126d and the thickness t12 of the end surface 126e of the developer accommodating container 126 is thinner than each of the thickness t13 of the end portion surface 126a, the thickness t14 of the end portion surface 126b and the thickness t15 of the central portion surface 126c of the developer accommodating container 126 provided along the direction crossing the mounting direction. For that reason, the end surfaces 126d and 126e of the developer accommodating container 126 are liable to cause buckling deformation with respect to the mounting direction E, so that the forces for deforming the developer accommodating container 126 become small. Accordingly, the reaction forces P11 and P12 are smaller than those in the case where the developer accommodating container 126 is formed in a uniform thickness as a whole.
Incidentally, between the end surface 126d of the developer accommodating container 126 and the end surface 140d of the frame 140 and between the end surface 126e of the developer accommodating container 126 and the end surface 140e of the frame 140, spacings L16 and L17 are provided, respectively, with respect to the longitudinal direction F. As described above, the developer accommodating container 126 does not permit the air permeation from the inside to the outside, and therefore when the developer accommodating container 126 is depressed by the frame 140, an inside volume of the developer accommodating container 126 is not changed. For that reason, the volume of the developer accommodating container 126 decreased due to a difference between the height L14 and each of the heights L11 and L12 is complemented by expansion of projected portions 126d1 and 126e1 of the developer accommodating container 126 into spacings L16 and L17, respectively. Further, also by movement of the developer T, the projected portions 126d1 and 126e1 expand into the spacings L16 and L17, respectively. As a result, the developer accommodating container 126 molded in larger size than the frame 140 can be accommodated between the first frame 117 and the second frame 118. Here, the projected portions 126d1 and 126e1 of the developer accommodating container 126 in a state in which the developer accommodating container 126 is accommodated between the first frame 117 and the second frame 118 are indicated by the solid line in (c) of
By the above-described constitution, even in the case where the developer accommodating container 126 including the depressed longitudinal end portions is accommodated in the frame 140, the degree of the deformation of the frame 140 by the reaction forces P11 and P12 of the developer accommodating container 126 can be decreased. For that reason, it is possible to decrease a degree of positional change of the process means such as the developing roller 13 to be mounted on the frame 140, so that the developing device 138 having a good image quality can be provided. Further, it is possible to provide the developer accommodating unit 125, the developing device 138, and the like which have a long lifetime without upsizing the frame 140.
Next, with reference to
Parts (a) to (c) of
Incidentally, the first state of the developer accommodating container 226 indicated by the chain double-dashed line shown in (c) of
As shown in (a) of
A fixing method of the developer accommodating container 226 to the second frame 218 is the same as that in Embodiment 1.
Next, as shown in (b) of
Next, as indicated by the chain double-dashed line in (c) of
That is, when the first frame 217 is moved from the state of (b) of
Here, a surface 226a1 of the developer accommodating container 226 in the state in which the developer accommodating container 226 is deformed and depressed by the opposing end portion surfaces 217a and 217b is indicated by the solid line in (c) of
For that reason, the frame 240 formed by the first frame 217 and the second frame 218 receives reaction forces P21 and P22 by depressing the developer accommodating container 226 at longitudinal end portion surfaces 240a and 240b, respectively.
Here, the frame 240 has a box-like shape extending in the longitudinal direction F as shown in (b) of
By the above-described constitution, even in the case where the developer accommodating container 226 including the depressed longitudinal end portions is accommodated in the frame 240, the degree of the deformation of the frame 240 by the reaction forces P21 and P22 of the developer accommodating container 226 can be decreased. For that reason, it is possible to decrease a degree of positional change of the process means such as the developing roller 13 to be mounted on the frame 240, so that the developing device 238 having a good image quality can be provided. Further, it is possible to provide the developer accommodating unit 225, the developing device 238, and the like which have a long lifetime without upsizing the frame 240.
Incidentally, in the above-described embodiments, the process cartridge integrally including the photosensitive drum and, as the process means, the charging means, the developing means and the cleaning means was illustrated as the process cartridge capable of being detachably mountable to the image forming apparatus. However, the process cartridge is not limited thereto but may also be a cartridge integrally including the developer carrying member and a developer unit in addition to the photosensitive drum. Further, the process cartridge may also be a process cartridge integrally including any one of the charging means and the cleaning means in addition to the photosensitive drum.
The embodiment, described at the final portion of Embodiment 1, in which the end surface of the developer accommodating container 26 with respect to the widthwise direction is deformed will be specifically described.
A relationship between the shape of the developer accommodating container 26 before being accommodated between the first and second frames 17 and 18 and the shape of the frame 40 including the first and second frames 17 and 18 for accommodating the developer accommodating container 26 will be described.
As shown in
As shown in
Incidentally, details of the mounting method of the first frame 17 to the second frame 18 will be described later as a mounting method of the developer accommodating container 26 into the frame 40.
Specifically, when a width of another configuration of the developer accommodating container 26 in an arbitrary position with respect to the direction perpendicular to the connecting sides 17b and 18c is a length L121 and a distance of an inner wall of the frame 40 in a position corresponding to the length L121 is a length L122, a relationship of (length L121)>(length L122) is satisfied.
Further, the developer accommodating member 34 is molded by changing angles of the surface 34f (first surface) including the opening 35 and the surface 34g (second surface) opposing the surface 34f with respect to the top surface 34k so that the sides 34f and 24g of the developer accommodating member 34 satisfy the following relationship. Here, the top surface 17a of the first frame 17 is a surface where the first frame 17 first contacts the developer accommodating member 34 during mounting.
With respect to the mounting direction, when an interior angle formed between the top surface 17a and the surface 34f is an angle θ11 and an interior angle formed between the top surface 17a and the surface 34j is an angle θ12, a relationship of (angle θ11)>(angle θ12) is satisfied.
(Mounting Method of Developer Accommodating Container into Frame)
The mounting method of the developer accommodating container 26 into the frame 40 will be described.
Parts (a), (b) and (c) of
First, as shown in (a) of
Next, with the second frame 18 on which the developer accommodating container 26 is fixed, the first frame 17 is mounted to respect to the direction E shown in (b) of
Therefore, when the first frame 17 is mounted to the second frame 18, the top surface 17a of the first frame 17 first contacts the top surface 34k of the developer accommodating member 34. The top surface 34k is a surface crossing both of the surface 34f including the opening 35 of the developer accommodating member 34 and the surface 34j opposing the surface 34f of the developer accommodating member 34. That is, the top surface 34k of the developer accommodating member 34 is a contact portion where the developer accommodating member 34 contacts the top surface 17a of the first frame 17.
Further, the developer accommodating container 26 has the flexibility, and therefore the developer accommodating container 26 is depressed and deformed in the mounting direction E by the top surface 17a of the first frame 17. At this time, the inside air is evacuated through the air-permeable portion 34b of the developer accommodating container 26 with respect to an arrow H direction of (b) of
Here, a relationship of forces exerted from the top surface 17a of the first frame 17 to the surface 34f including the opening 35 of the developer accommodating member 34 and forces exerted from the top surface 17a of the first frame 17 to the surface 34j opposing the surface 34f of the developer accommodating member 34 is shown below.
As shown in (b) of
On the bent portion 34n, the following forces are exerted.
Force component parallel to surface 34f including opening 35: F1x
F1x=F×cos|θ11−90°|
Force component perpendicular to surface 34f including opening 35: F1y
F1y=F×sin|θ11−90°|
Force component parallel to top surface 17a of the first frame 17: F1yy
F1yy=F×sin|θ11−90°|×cos|θ11−90°|
Here, sin θ×cos θ=(sin 2θ)/2, and therefore,
F1yy=F×(sin(2θ|θ11−90°|))/2.
On the other hand, on the bent portion 34m, the following forces are exerted.
Force component parallel to surface 34j: F2x
F2x=F×cos|θ12−90°|
Force component perpendicular to surface 34j: F2y
F2y=F×sin|θ12−90°|
Force component parallel to top surface 17a of first frame 17: F2yy
Here, the force F1x is a force component for bending the surface 34f of the developer accommodating member 34 (for forming a crease), and the force F2x is a force component for bending the surface 34j of the developer accommodating member 34 (for forming a crease). A large force component shows that the surface is liable to be bent. Further, the force F1yy is force component for causing the surface 34 of the developer accommodating member 34 to fall, and the force F2yy is a force component for causing the surface 34j of the developer accommodating member 34 to fall. A larger force component shows that the surface is liable to fall.
Here, by satisfying a relationship of (angle θ11)>(angle θ12), (force F1x)<(force F2x) and (force F1yy)>(force F2yy) are satisfied.
For this reason, when the developer accommodating container 26 is deformed and depressed in the direction E by the top surface 17a of the first frame 17, based on the force relationship of F1x<F2x, the surface 34j opposing the surface 34f including the opening 35 is positively bent rather than the surface 34f including the opening 35 of the developer accommodating member 34.
Further, based on the force relationship of F1yy>F2yy, the bent portions 34m and 34n of the developer accommodating member 34 are moved in an arrow Q direction. Further, the surface 34f including the opening 35 positively falls toward the inside of the developer accommodating member 34 (in the arrow Q direction of (b) of
Therefore, the bent portion 34n of the developer accommodating container 26 is moved in the arrow Q direction, so that the force F1x exerted on the surface 34f including the opening 35 is released. As a result, it becomes possible to accommodate the developer accommodating container 26 between the first and second frames 17 and 18 while preventing folding and crease at the surface 34f.
For this reason, the folding and crease at the opening can be prevented without particularly providing a mechanism for expanding the opening by a leaf spring or the like in the neighborhood of the opening, so that it becomes possible to satisfactorily discharge the developer from the developer accommodating container at a low cost.
Incidentally, the surface 34j of the developer accommodating container 26 is caused to fall toward an outside of the developer accommodating container 26, so that a part of the developer accommodating container 26 is accommodated in a space above the developer accommodating container 26.
Further, it becomes possible to prevent the deformation of the opening 35 by preventing the surface 34f including the opening 35 from generating the folding and crease, so that it is possible to stably supply the developer 39.
From the above, as shown in (c) of
Incidentally, in this embodiment, the developing device 38 as a unit prepared by integrally mounting the developing roller 13, the developing blade 15 and the developer accommodating container 26 was described, but the present invention is not limited thereto. For example, it is also possible to employ a constitution in which the developing device 38 including the developing blade 15 and the frame 40 and the developer accommodating unit 25 including the developer accommodating container 26 are mounted as separate members in the image forming apparatus.
In this embodiment, a constitution different from the constitution in Embodiment 4 with respect to the shape relationship between the developer accommodating container and the developing device is employed.
In this embodiment, different from Embodiment 4, the case of a constitution in which the top surface 17a of the first frame 17 is not parallel to the top surface 34k of the developer accommodating member 34 and is not perpendicular to the mounting direction E will be described.
Incidentally, identical and similar portions to those in Embodiment 1 are represented by the same reference numerals or symbols and will be omitted from redundant description.
A relationship between the shape of the developer accommodating container 126 before being accommodated between the first and second frames 117 and 118 and the shape of the frame 140, including the first and second frames 117 and 118, for accommodating the developer accommodating container 126 will be described.
Parts (a), (b) and (c) of
As shown in (a) of
Incidentally, details of the mounting method of the first frame 117 with the second frame 118 will be described later as a mounting method of the developer accommodating container 126 into the frame 140.
Here, a width of another configuration of the developer accommodating container 126 in an arbitrary position with respect to the direction perpendicular to the connecting sides 117b and 118b is a length L53. Further, a distance of an inner wall of the frame 140 in a position corresponding to the length L53 is a length L54. Then, a relationship such that (length L53)>(length L54) is satisfied is provided.
Further, in this embodiment, a top surface 117a (contact side) of the first frame 117 first contacting the developer accommodating member 134 of the developer accommodating container 126 during the mounting is characterized by satisfying the following relationship.
That is, when an interior angle formed between the top surface 117a of the first frame 117 and a surface 134f (first surface) including the opening 135 of the developer accommodating member 134 is an angle θ13, the top surface 117a is inclined so as to satisfy a relationship of 90°<(angle 3)<180°. Further, a space in which the depressed developer accommodating container 126 is to be accommodated when the first and second frames 117 and 118 are connected with each other (as indicated by a hatched line K of (a) of
(Mounting Method of Developer Accommodating Container into Frame)
The mounting method of the developer accommodating container 126 into the frame 140 will be described. Part (b) of
Next, with the second frame 118 on which the developer accommodating container 126 is fixed, the first frame 117 is mounted to respect to the direction E shown in (b) of
Therefore, when the first frame 117 is mounted to the second frame 118, the top surface 117a of the first frame 117 first contacts the bent portion 134n. That is, the bent portion 134n of the developer accommodating member 134 is a contact portion where the developer accommodating member 134 contacts the top surface 117a of the first frame 17.
As shown in (b) of
Further, the developer accommodating container 126 has the flexibility, and therefore the developer accommodating container 126 is depressed and deformed in the mounting direction E by the top surface 117a of the first frame 117. At this time, the inside air is, similarly as in Embodiment 1, evacuated through an air-permeable member 116 of the developer accommodating container 126 with respect to an arrow H direction of (b) of
Here, a relationship of forces exerted from the top surface 117a of the first frame 117 to the surface 134f including the opening 135 of the developer accommodating member 134 to the surface 134j opposing the surface 134f of the developer accommodating member 134 is shown below.
As shown in (b) of
Force component parallel to surface 134f including opening 135: F3x
F3x=F×cos|θ13−90°|
Force component perpendicular to surface 134f including opening 135: F3y
F3y=F×sin|θ13−90°|
Force component parallel to top surface 117a of the first frame 117: F3yy
Here, the angle θ13 as an interior angle formed between the top surface 117a of the first frame 117 and the surface 134f including the opening 135 of the developer accommodating member 134 satisfies a relationship of 90°<(angle θ13)<180°. Therefore, the force F3yy as a component force of the force, in the arrow F direction, acting on the top surface 117a with respect to the perpendicular direction satisfies F3yy>0, and thus acts in the arrow Q direction of (b) of
Therefore, the bent portion 134n of the developer accommodating container 126 is moved in the arrow Q direction, so that the force F3x exerted on the surface 134f including the opening 135 is released.
Then, the surface 134f including the opening 135 of the developer accommodating member 134 falls toward the inside of the developer accommodating member 134 (in the arrow Q direction of (b) of
From the above, as shown in (c) of
Further, it becomes possible to prevent the deformation of the opening 135 by preventing the surface 134f including the opening 135 from generating the folding and crease, so that it is possible to stably supply the developer 139.
Further, in the above-described embodiments, the developer accommodating unit (or the developing device) in the process cartridge was described as an example but the present invention is not limited thereto. The present invention is also effective even in a developer accommodating unit (or a developing device) which is provided separately from the process cartridge and which is detachably mountable to the image forming apparatus. Further, in the embodiments described above, the constitution (developing device) in which the developer accommodating unit integrally includes the developing roller as the developer carrying member was shown as an example, but as described above, the present invention is also effective with respect to the developer accommodating unit from which the developing roller is provided separately.
Further, in the above-described embodiments, the constitution in which the process cartridge including the photosensitive drum is detachably mountable to the image forming apparatus was illustrated, but the present invention is not limited thereto. For example, it is also possible to use an image forming apparatus in which respective constituent members are incorporated or an image forming apparatus to which the respective constituent members are detachably mountable.
Further, in the embodiments described above, the printer is illustrated as the image forming apparatus, but the present invention is not limited thereto. For example, it is possible to use other image forming apparatuses such as a copying machine, a facsimile machine and a multi-function machine having functions of these machines. By applying the present invention to those image forming apparatuses, a similar effect can be obtained.
According to the present invention, it is possible to provide the developer accommodating unit, the developing device, the process cartridge and the image forming apparatus which are long in lifetime without upsizing the frame. Further, by decreasing a degree of the deformation due to the repelling force of the deformable flexible container, it is possible to prevent a lowering in image quality due to the deformation of the frame.
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 Applications Nos. 273200/2012 filed Dec. 14, 2012, 019145/2013 filed Feb. 4, 2013 and 236404/2013 filed Nov. 15, 2013, which are hereby incorporated by reference.
Number | Date | Country | Kind |
---|---|---|---|
2012-273200 | Dec 2012 | JP | national |
2013-019145 | Feb 2013 | JP | national |
2013-236404 | Nov 2013 | JP | national |